diff options
Diffstat (limited to 'mfbt')
184 files changed, 45354 insertions, 0 deletions
diff --git a/mfbt/Alignment.h b/mfbt/Alignment.h new file mode 100644 index 000000000..4fcda4f3e --- /dev/null +++ b/mfbt/Alignment.h @@ -0,0 +1,154 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Functionality related to memory alignment. */ + +#ifndef mozilla_Alignment_h +#define mozilla_Alignment_h + +#include "mozilla/Attributes.h" +#include <stddef.h> +#include <stdint.h> + +namespace mozilla { + +/* + * This class, and the corresponding macro MOZ_ALIGNOF, figures out how many + * bytes of alignment a given type needs. + */ +template<typename T> +class AlignmentFinder +{ + struct Aligner + { + char mChar; + T mT; + }; + +public: + static const size_t alignment = sizeof(Aligner) - sizeof(T); +}; + +#define MOZ_ALIGNOF(T) mozilla::AlignmentFinder<T>::alignment + +/* + * Declare the MOZ_ALIGNED_DECL macro for declaring aligned types. + * + * For instance, + * + * MOZ_ALIGNED_DECL(char arr[2], 8); + * + * will declare a two-character array |arr| aligned to 8 bytes. + */ + +#if defined(__GNUC__) +# define MOZ_ALIGNED_DECL(_type, _align) \ + _type __attribute__((aligned(_align))) +#elif defined(_MSC_VER) +# define MOZ_ALIGNED_DECL(_type, _align) \ + __declspec(align(_align)) _type +#else +# warning "We don't know how to align variables on this compiler." +# define MOZ_ALIGNED_DECL(_type, _align) _type +#endif + +/* + * AlignedElem<N> is a structure whose alignment is guaranteed to be at least N + * bytes. + * + * We support 1, 2, 4, 8, and 16-bit alignment. + */ +template<size_t Align> +struct AlignedElem; + +/* + * We have to specialize this template because GCC doesn't like + * __attribute__((aligned(foo))) where foo is a template parameter. + */ + +template<> +struct AlignedElem<1> +{ + MOZ_ALIGNED_DECL(uint8_t elem, 1); +}; + +template<> +struct AlignedElem<2> +{ + MOZ_ALIGNED_DECL(uint8_t elem, 2); +}; + +template<> +struct AlignedElem<4> +{ + MOZ_ALIGNED_DECL(uint8_t elem, 4); +}; + +template<> +struct AlignedElem<8> +{ + MOZ_ALIGNED_DECL(uint8_t elem, 8); +}; + +template<> +struct AlignedElem<16> +{ + MOZ_ALIGNED_DECL(uint8_t elem, 16); +}; + +/* + * This utility pales in comparison to Boost's aligned_storage. The utility + * simply assumes that uint64_t is enough alignment for anyone. This may need + * to be extended one day... + * + * As an important side effect, pulling the storage into this template is + * enough obfuscation to confuse gcc's strict-aliasing analysis into not giving + * false negatives when we cast from the char buffer to whatever type we've + * constructed using the bytes. + */ +template<size_t Nbytes> +struct AlignedStorage +{ + union U + { + char mBytes[Nbytes]; + uint64_t mDummy; + } u; + + const void* addr() const { return u.mBytes; } + void* addr() { return u.mBytes; } + + AlignedStorage() = default; + + // AlignedStorage is non-copyable: the default copy constructor violates + // strict aliasing rules, per bug 1269319. + AlignedStorage(const AlignedStorage&) = delete; + void operator=(const AlignedStorage&) = delete; +}; + +template<typename T> +struct MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS AlignedStorage2 +{ + union U + { + char mBytes[sizeof(T)]; + uint64_t mDummy; + } u; + + const T* addr() const { return reinterpret_cast<const T*>(u.mBytes); } + T* addr() { return static_cast<T*>(static_cast<void*>(u.mBytes)); } + + AlignedStorage2() = default; + + // AlignedStorage2 is non-copyable: the default copy constructor violates + // strict aliasing rules, per bug 1269319. + AlignedStorage2(const AlignedStorage2&) = delete; + void operator=(const AlignedStorage2&) = delete; +}; + +} /* namespace mozilla */ + +#endif /* mozilla_Alignment_h */ diff --git a/mfbt/AllocPolicy.h b/mfbt/AllocPolicy.h new file mode 100644 index 000000000..81f62b038 --- /dev/null +++ b/mfbt/AllocPolicy.h @@ -0,0 +1,133 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* + * An allocation policy concept, usable for structures and algorithms to + * control how memory is allocated and how failures are handled. + */ + +#ifndef mozilla_AllocPolicy_h +#define mozilla_AllocPolicy_h + +#include "mozilla/Attributes.h" +#include "mozilla/TemplateLib.h" + +#include <stddef.h> +#include <stdlib.h> + +namespace mozilla { + +/* + * Allocation policies are used to implement the standard allocation behaviors + * in a customizable way. Additionally, custom behaviors may be added to these + * behaviors, such as additionally reporting an error through an out-of-band + * mechanism when OOM occurs. The concept modeled here is as follows: + * + * - public copy constructor, assignment, destructor + * - template <typename T> T* maybe_pod_malloc(size_t) + * Fallible, but doesn't report an error on OOM. + * - template <typename T> T* maybe_pod_calloc(size_t) + * Fallible, but doesn't report an error on OOM. + * - template <typename T> T* maybe_pod_realloc(T*, size_t, size_t) + * Fallible, but doesn't report an error on OOM. The old allocation + * size is passed in, in addition to the new allocation size requested. + * - template <typename T> T* pod_malloc(size_t) + * Responsible for OOM reporting when null is returned. + * - template <typename T> T* pod_calloc(size_t) + * Responsible for OOM reporting when null is returned. + * - template <typename T> T* pod_realloc(T*, size_t, size_t) + * Responsible for OOM reporting when null is returned. The old allocation + * size is passed in, in addition to the new allocation size requested. + * - void free_(void*) + * - void reportAllocOverflow() const + * Called on allocation overflow (that is, an allocation implicitly tried + * to allocate more than the available memory space -- think allocating an + * array of large-size objects, where N * size overflows) before null is + * returned. + * - bool checkSimulatedOOM() const + * Some clients generally allocate memory yet in some circumstances won't + * need to do so. For example, appending to a vector with a small amount of + * inline storage generally allocates memory, but no allocation occurs + * unless appending exceeds inline storage. But for testing purposes, it + * can be useful to treat *every* operation as allocating. + * Clients (such as this hypothetical append method implementation) should + * call this method in situations that don't allocate, but could generally, + * to support this. The default behavior should return true; more + * complicated behavior might be to return false only after a certain + * number of allocations-or-check-simulated-OOMs (coordinating with the + * other AllocPolicy methods) have occurred. + * + * mfbt provides (and typically uses by default) only MallocAllocPolicy, which + * does nothing more than delegate to the malloc/alloc/free functions. + */ + +/* + * A policy that straightforwardly uses malloc/calloc/realloc/free and adds no + * extra behaviors. + */ +class MallocAllocPolicy +{ +public: + template <typename T> + T* maybe_pod_malloc(size_t aNumElems) + { + if (aNumElems & mozilla::tl::MulOverflowMask<sizeof(T)>::value) { + return nullptr; + } + return static_cast<T*>(malloc(aNumElems * sizeof(T))); + } + + template <typename T> + T* maybe_pod_calloc(size_t aNumElems) + { + return static_cast<T*>(calloc(aNumElems, sizeof(T))); + } + + template <typename T> + T* maybe_pod_realloc(T* aPtr, size_t aOldSize, size_t aNewSize) + { + if (aNewSize & mozilla::tl::MulOverflowMask<sizeof(T)>::value) { + return nullptr; + } + return static_cast<T*>(realloc(aPtr, aNewSize * sizeof(T))); + } + + template <typename T> + T* pod_malloc(size_t aNumElems) + { + return maybe_pod_malloc<T>(aNumElems); + } + + template <typename T> + T* pod_calloc(size_t aNumElems) + { + return maybe_pod_calloc<T>(aNumElems); + } + + template <typename T> + T* pod_realloc(T* aPtr, size_t aOldSize, size_t aNewSize) + { + return maybe_pod_realloc<T>(aPtr, aOldSize, aNewSize); + } + + void free_(void* aPtr) + { + free(aPtr); + } + + void reportAllocOverflow() const + { + } + + MOZ_MUST_USE bool checkSimulatedOOM() const + { + return true; + } +}; + +} // namespace mozilla + +#endif /* mozilla_AllocPolicy_h */ diff --git a/mfbt/AlreadyAddRefed.h b/mfbt/AlreadyAddRefed.h new file mode 100644 index 000000000..0d7b0caed --- /dev/null +++ b/mfbt/AlreadyAddRefed.h @@ -0,0 +1,147 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Typed temporary pointers for reference-counted smart pointers. */ + +#ifndef AlreadyAddRefed_h +#define AlreadyAddRefed_h + +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" +#include "mozilla/Move.h" + +namespace mozilla { + +struct unused_t; + +} // namespace mozilla + +/** + * already_AddRefed cooperates with reference counting smart pointers to enable + * you to assign in a pointer _without_ |AddRef|ing it. You might want to use + * this as a return type from a function that returns an already |AddRef|ed + * pointer. + * + * TODO Move already_AddRefed to namespace mozilla. This has not yet been done + * because of the sheer number of usages of already_AddRefed. + */ +template<class T> +struct MOZ_MUST_USE_TYPE MOZ_NON_AUTOABLE already_AddRefed +{ + /* + * We want to allow returning nullptr from functions returning + * already_AddRefed<T>, for simplicity. But we also don't want to allow + * returning raw T*, instead preferring creation of already_AddRefed<T> from + * a reference counting smart pointer. + * + * We address the latter requirement by making the (T*) constructor explicit. + * But |return nullptr| won't consider an explicit constructor, so we need + * another constructor to handle it. Plain old (decltype(nullptr)) doesn't + * cut it, because if nullptr is emulated as __null (with type int or long), + * passing nullptr to an int/long parameter triggers compiler warnings. We + * need a type that no one can pass accidentally; a pointer-to-member-function + * (where no such function exists) does the trick nicely. + * + * That handles the return-value case. What about for locals, argument types, + * and so on? |already_AddRefed<T>(nullptr)| considers both overloads (and + * the (already_AddRefed<T>&&) overload as well!), so there's an ambiguity. + * We can target true nullptr using decltype(nullptr), but we can't target + * emulated nullptr the same way, because passing __null to an int/long + * parameter triggers compiler warnings. So just give up on this, and provide + * this behavior through the default constructor. + * + * We can revert to simply explicit (T*) and implicit (decltype(nullptr)) when + * nullptr no longer needs to be emulated to support the ancient b2g compiler. + * (The () overload could also be removed, if desired, if we changed callers.) + */ + already_AddRefed() : mRawPtr(nullptr) {} + + // The return and argument types here are arbitrarily selected so no + // corresponding member function exists. + typedef void (already_AddRefed::* MatchNullptr)(double, float); + MOZ_IMPLICIT already_AddRefed(MatchNullptr aRawPtr) : mRawPtr(nullptr) {} + + explicit already_AddRefed(T* aRawPtr) : mRawPtr(aRawPtr) {} + + // Disallow copy constructor and copy assignment operator: move semantics used instead. + already_AddRefed(const already_AddRefed<T>& aOther) = delete; + already_AddRefed<T>& operator=(const already_AddRefed<T>& aOther) = delete; + + already_AddRefed(already_AddRefed<T>&& aOther) : mRawPtr(aOther.take()) {} + + already_AddRefed<T>& operator=(already_AddRefed<T>&& aOther) + { + mRawPtr = aOther.take(); + return *this; + } + + /** + * This helper is useful in cases like + * + * already_AddRefed<BaseClass> + * Foo() + * { + * RefPtr<SubClass> x = ...; + * return x.forget(); + * } + * + * The autoconversion allows one to omit the idiom + * + * RefPtr<BaseClass> y = x.forget(); + * return y.forget(); + * + * Note that nsRefPtr is the XPCOM reference counting smart pointer class. + */ + template <typename U> + MOZ_IMPLICIT already_AddRefed(already_AddRefed<U>&& aOther) : mRawPtr(aOther.take()) {} + + ~already_AddRefed() { MOZ_ASSERT(!mRawPtr); } + + // Specialize the unused operator<< for already_AddRefed, to allow + // nsCOMPtr<nsIFoo> foo; + // Unused << foo.forget(); + // Note that nsCOMPtr is the XPCOM reference counting smart pointer class. + friend void operator<<(const mozilla::unused_t& aUnused, + const already_AddRefed<T>& aRhs) + { + auto mutableAlreadyAddRefed = const_cast<already_AddRefed<T>*>(&aRhs); + aUnused << mutableAlreadyAddRefed->take(); + } + + MOZ_MUST_USE T* take() + { + T* rawPtr = mRawPtr; + mRawPtr = nullptr; + return rawPtr; + } + + /** + * This helper provides a static_cast replacement for already_AddRefed, so + * if you have + * + * already_AddRefed<Parent> F(); + * + * you can write + * + * already_AddRefed<Child> + * G() + * { + * return F().downcast<Child>(); + * } + */ + template<class U> + already_AddRefed<U> downcast() + { + U* tmp = static_cast<U*>(mRawPtr); + mRawPtr = nullptr; + return already_AddRefed<U>(tmp); + } + +private: + T* MOZ_OWNING_REF mRawPtr; +}; + +#endif // AlreadyAddRefed_h diff --git a/mfbt/Array.h b/mfbt/Array.h new file mode 100644 index 000000000..72b89ede1 --- /dev/null +++ b/mfbt/Array.h @@ -0,0 +1,88 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* A compile-time constant-length array with bounds-checking assertions. */ + +#ifndef mozilla_Array_h +#define mozilla_Array_h + +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" +#include "mozilla/Move.h" +#include "mozilla/ReverseIterator.h" + +#include <stddef.h> + +namespace mozilla { + +template<typename T, size_t Length> +class Array +{ + T mArr[Length]; + +public: + Array() {} + + template <typename... Args> + MOZ_IMPLICIT Array(Args&&... aArgs) + : mArr{mozilla::Forward<Args>(aArgs)...} + { + static_assert(sizeof...(aArgs) == Length, + "The number of arguments should be equal to the template parameter Length"); + } + + T& operator[](size_t aIndex) + { + MOZ_ASSERT(aIndex < Length); + return mArr[aIndex]; + } + + const T& operator[](size_t aIndex) const + { + MOZ_ASSERT(aIndex < Length); + return mArr[aIndex]; + } + + typedef T* iterator; + typedef const T* const_iterator; + typedef ReverseIterator<T*> reverse_iterator; + typedef ReverseIterator<const T*> const_reverse_iterator; + + // Methods for range-based for loops. + iterator begin() { return mArr; } + const_iterator begin() const { return mArr; } + const_iterator cbegin() const { return begin(); } + iterator end() { return mArr + Length; } + const_iterator end() const { return mArr + Length; } + const_iterator cend() const { return end(); } + + // Methods for reverse iterating. + reverse_iterator rbegin() { return reverse_iterator(end()); } + const_reverse_iterator rbegin() const { return const_reverse_iterator(end()); } + const_reverse_iterator crbegin() const { return rbegin(); } + reverse_iterator rend() { return reverse_iterator(begin()); } + const_reverse_iterator rend() const { return const_reverse_iterator(begin()); } + const_reverse_iterator crend() const { return rend(); } +}; + +template<typename T> +class Array<T, 0> +{ +public: + T& operator[](size_t aIndex) + { + MOZ_CRASH("indexing into zero-length array"); + } + + const T& operator[](size_t aIndex) const + { + MOZ_CRASH("indexing into zero-length array"); + } +}; + +} /* namespace mozilla */ + +#endif /* mozilla_Array_h */ diff --git a/mfbt/ArrayUtils.h b/mfbt/ArrayUtils.h new file mode 100644 index 000000000..50236ccb7 --- /dev/null +++ b/mfbt/ArrayUtils.h @@ -0,0 +1,194 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* + * Implements various helper functions related to arrays. + */ + +#ifndef mozilla_ArrayUtils_h +#define mozilla_ArrayUtils_h + +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" + +#include <stddef.h> + +#ifdef __cplusplus + +#include "mozilla/Alignment.h" +#include "mozilla/Array.h" +#include "mozilla/EnumeratedArray.h" +#include "mozilla/TypeTraits.h" + +namespace mozilla { + +/* + * Safely subtract two pointers when it is known that aEnd >= aBegin, yielding a + * size_t result. + * + * Ordinary pointer subtraction yields a ptrdiff_t result, which, being signed, + * has insufficient range to express the distance between pointers at opposite + * ends of the address space. Furthermore, most compilers use ptrdiff_t to + * represent the intermediate byte address distance, before dividing by + * sizeof(T); if that intermediate result overflows, they'll produce results + * with the wrong sign even when the correct scaled distance would fit in a + * ptrdiff_t. + */ +template<class T> +MOZ_ALWAYS_INLINE size_t +PointerRangeSize(T* aBegin, T* aEnd) +{ + MOZ_ASSERT(aEnd >= aBegin); + return (size_t(aEnd) - size_t(aBegin)) / sizeof(T); +} + +/* + * Compute the length of an array with constant length. (Use of this method + * with a non-array pointer will not compile.) + * + * Beware of the implicit trailing '\0' when using this with string constants. + */ +template<typename T, size_t N> +constexpr size_t +ArrayLength(T (&aArr)[N]) +{ + return N; +} + +template<typename T, size_t N> +constexpr size_t +ArrayLength(const Array<T, N>& aArr) +{ + return N; +} + +template<typename E, E N, typename T> +constexpr size_t +ArrayLength(const EnumeratedArray<E, N, T>& aArr) +{ + return size_t(N); +} + +/* + * Compute the address one past the last element of a constant-length array. + * + * Beware of the implicit trailing '\0' when using this with string constants. + */ +template<typename T, size_t N> +constexpr T* +ArrayEnd(T (&aArr)[N]) +{ + return aArr + ArrayLength(aArr); +} + +template<typename T, size_t N> +constexpr T* +ArrayEnd(Array<T, N>& aArr) +{ + return &aArr[0] + ArrayLength(aArr); +} + +template<typename T, size_t N> +constexpr const T* +ArrayEnd(const Array<T, N>& aArr) +{ + return &aArr[0] + ArrayLength(aArr); +} + +namespace detail { + +template<typename AlignType, typename Pointee, + typename = EnableIf<!IsVoid<AlignType>::value>> +struct AlignedChecker +{ + static void + test(const Pointee* aPtr) + { + MOZ_ASSERT((uintptr_t(aPtr) % MOZ_ALIGNOF(AlignType)) == 0, + "performing a range-check with a misaligned pointer"); + } +}; + +template<typename AlignType, typename Pointee> +struct AlignedChecker<AlignType, Pointee> +{ + static void + test(const Pointee* aPtr) + { + } +}; + +} // namespace detail + +/** + * Determines whether |aPtr| points at an object in the range [aBegin, aEnd). + * + * |aPtr| must have the same alignment as |aBegin| and |aEnd|. This usually + * should be achieved by ensuring |aPtr| points at a |U|, not just that it + * points at a |T|. + * + * It is a usage error for any argument to be misaligned. + * + * It's okay for T* to be void*, and if so U* may also be void*. In the latter + * case no argument is required to be aligned (obviously, as void* implies no + * particular alignment). + */ +template<typename T, typename U> +inline typename EnableIf<IsSame<T, U>::value || + IsBaseOf<T, U>::value || + IsVoid<T>::value, + bool>::Type +IsInRange(const T* aPtr, const U* aBegin, const U* aEnd) +{ + MOZ_ASSERT(aBegin <= aEnd); + detail::AlignedChecker<U, T>::test(aPtr); + detail::AlignedChecker<U, U>::test(aBegin); + detail::AlignedChecker<U, U>::test(aEnd); + return aBegin <= reinterpret_cast<const U*>(aPtr) && + reinterpret_cast<const U*>(aPtr) < aEnd; +} + +/** + * Convenience version of the above method when the valid range is specified as + * uintptr_t values. As above, |aPtr| must be aligned, and |aBegin| and |aEnd| + * must be aligned with respect to |T|. + */ +template<typename T> +inline bool +IsInRange(const T* aPtr, uintptr_t aBegin, uintptr_t aEnd) +{ + return IsInRange(aPtr, + reinterpret_cast<const T*>(aBegin), + reinterpret_cast<const T*>(aEnd)); +} + +namespace detail { + +/* + * Helper for the MOZ_ARRAY_LENGTH() macro to make the length a typesafe + * compile-time constant even on compilers lacking constexpr support. + */ +template <typename T, size_t N> +char (&ArrayLengthHelper(T (&array)[N]))[N]; + +} /* namespace detail */ + +} /* namespace mozilla */ + +#endif /* __cplusplus */ + +/* + * MOZ_ARRAY_LENGTH() is an alternative to mozilla::ArrayLength() for C files + * that can't use C++ template functions and for static_assert() calls that + * can't call ArrayLength() when it is not a C++11 constexpr function. + */ +#ifdef __cplusplus +# define MOZ_ARRAY_LENGTH(array) sizeof(mozilla::detail::ArrayLengthHelper(array)) +#else +# define MOZ_ARRAY_LENGTH(array) (sizeof(array)/sizeof((array)[0])) +#endif + +#endif /* mozilla_ArrayUtils_h */ diff --git a/mfbt/Assertions.cpp b/mfbt/Assertions.cpp new file mode 100644 index 000000000..62630842d --- /dev/null +++ b/mfbt/Assertions.cpp @@ -0,0 +1,66 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/Atomics.h" + +#include <stdarg.h> + +MOZ_BEGIN_EXTERN_C + +/* + * The crash reason is defined as a global variable here rather than in the + * crash reporter itself to make it available to all code, even libraries like + * JS that don't link with the crash reporter directly. This value will only + * be consumed if the crash reporter is used by the target application. + */ +MFBT_DATA const char* gMozCrashReason = nullptr; + +#ifndef DEBUG +MFBT_API MOZ_COLD MOZ_NORETURN MOZ_NEVER_INLINE void +MOZ_CrashOOL(int aLine, const char* aReason) +#else +MFBT_API MOZ_COLD MOZ_NORETURN MOZ_NEVER_INLINE void +MOZ_CrashOOL(const char* aFilename, int aLine, const char* aReason) +#endif +{ +#ifdef DEBUG + MOZ_ReportCrash(aReason, aFilename, aLine); +#endif + MOZ_CRASH_ANNOTATE(aReason); + MOZ_REALLY_CRASH(aLine); +} + +static char sPrintfCrashReason[sPrintfCrashReasonSize] = {}; +static mozilla::Atomic<bool> sCrashing(false); + +#ifndef DEBUG +MFBT_API MOZ_COLD MOZ_NORETURN MOZ_NEVER_INLINE MOZ_FORMAT_PRINTF(2, 3) void +MOZ_CrashPrintf(int aLine, const char* aFormat, ...) +#else +MFBT_API MOZ_COLD MOZ_NORETURN MOZ_NEVER_INLINE MOZ_FORMAT_PRINTF(3, 4) void +MOZ_CrashPrintf(const char* aFilename, int aLine, const char* aFormat, ...) +#endif +{ + if (!sCrashing.compareExchange(false, true)) { + // In the unlikely event of a race condition, skip + // setting the crash reason and just crash safely. + MOZ_REALLY_CRASH(aLine); + } + va_list aArgs; + va_start(aArgs, aFormat); + int ret = vsnprintf(sPrintfCrashReason, sPrintfCrashReasonSize, + aFormat, aArgs); + va_end(aArgs); + MOZ_RELEASE_ASSERT(ret >= 0 && size_t(ret) < sPrintfCrashReasonSize, + "Could not write the explanation string to the supplied buffer!"); +#ifdef DEBUG + MOZ_ReportCrash(sPrintfCrashReason, aFilename, aLine); +#endif + MOZ_CRASH_ANNOTATE(sPrintfCrashReason); + MOZ_REALLY_CRASH(aLine); +} + +MOZ_END_EXTERN_C diff --git a/mfbt/Assertions.h b/mfbt/Assertions.h new file mode 100644 index 000000000..e7b010b7f --- /dev/null +++ b/mfbt/Assertions.h @@ -0,0 +1,637 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Implementations of runtime and static assertion macros for C and C++. */ + +#ifndef mozilla_Assertions_h +#define mozilla_Assertions_h + +#if defined(MOZILLA_INTERNAL_API) && defined(__cplusplus) +#define MOZ_DUMP_ASSERTION_STACK +#endif + +#include "mozilla/Attributes.h" +#include "mozilla/Compiler.h" +#include "mozilla/Likely.h" +#include "mozilla/MacroArgs.h" +#include "mozilla/StaticAnalysisFunctions.h" +#include "mozilla/Types.h" +#ifdef MOZ_DUMP_ASSERTION_STACK +#include "nsTraceRefcnt.h" +#endif + +#if defined(MOZ_HAS_MOZGLUE) || defined(MOZILLA_INTERNAL_API) +/* + * The crash reason set by MOZ_CRASH_ANNOTATE is consumed by the crash reporter + * if present. It is declared here (and defined in Assertions.cpp) to make it + * available to all code, even libraries that don't link with the crash reporter + * directly. + */ +MOZ_BEGIN_EXTERN_C +extern MFBT_DATA const char* gMozCrashReason; +MOZ_END_EXTERN_C + +static inline void +AnnotateMozCrashReason(const char* reason) +{ + gMozCrashReason = reason; +} +# define MOZ_CRASH_ANNOTATE(...) AnnotateMozCrashReason(__VA_ARGS__) +#else +# define MOZ_CRASH_ANNOTATE(...) do { /* nothing */ } while (0) +#endif + +#include <stddef.h> +#include <stdio.h> +#include <stdlib.h> +#ifdef WIN32 + /* + * TerminateProcess and GetCurrentProcess are defined in <winbase.h>, which + * further depends on <windef.h>. We hardcode these few definitions manually + * because those headers clutter the global namespace with a significant + * number of undesired macros and symbols. + */ +# ifdef __cplusplus +extern "C" { +# endif +__declspec(dllimport) int __stdcall +TerminateProcess(void* hProcess, unsigned int uExitCode); +__declspec(dllimport) void* __stdcall GetCurrentProcess(void); +# ifdef __cplusplus +} +# endif +#else +# include <signal.h> +#endif +#ifdef ANDROID +# include <android/log.h> +#endif + +/* + * MOZ_STATIC_ASSERT may be used to assert a condition *at compile time* in C. + * In C++11, static_assert is provided by the compiler to the same effect. + * This can be useful when you make certain assumptions about what must hold for + * optimal, or even correct, behavior. For example, you might assert that the + * size of a struct is a multiple of the target architecture's word size: + * + * struct S { ... }; + * // C + * MOZ_STATIC_ASSERT(sizeof(S) % sizeof(size_t) == 0, + * "S should be a multiple of word size for efficiency"); + * // C++11 + * static_assert(sizeof(S) % sizeof(size_t) == 0, + * "S should be a multiple of word size for efficiency"); + * + * This macro can be used in any location where both an extern declaration and a + * typedef could be used. + */ +#ifndef __cplusplus + /* + * Some of the definitions below create an otherwise-unused typedef. This + * triggers compiler warnings with some versions of gcc, so mark the typedefs + * as permissibly-unused to disable the warnings. + */ +# if defined(__GNUC__) +# define MOZ_STATIC_ASSERT_UNUSED_ATTRIBUTE __attribute__((unused)) +# else +# define MOZ_STATIC_ASSERT_UNUSED_ATTRIBUTE /* nothing */ +# endif +# define MOZ_STATIC_ASSERT_GLUE1(x, y) x##y +# define MOZ_STATIC_ASSERT_GLUE(x, y) MOZ_STATIC_ASSERT_GLUE1(x, y) +# if defined(__SUNPRO_CC) + /* + * The Sun Studio C++ compiler is buggy when declaring, inside a function, + * another extern'd function with an array argument whose length contains a + * sizeof, triggering the error message "sizeof expression not accepted as + * size of array parameter". This bug (6688515, not public yet) would hit + * defining moz_static_assert as a function, so we always define an extern + * array for Sun Studio. + * + * We include the line number in the symbol name in a best-effort attempt + * to avoid conflicts (see below). + */ +# define MOZ_STATIC_ASSERT(cond, reason) \ + extern char MOZ_STATIC_ASSERT_GLUE(moz_static_assert, __LINE__)[(cond) ? 1 : -1] +# elif defined(__COUNTER__) + /* + * If there was no preferred alternative, use a compiler-agnostic version. + * + * Note that the non-__COUNTER__ version has a bug in C++: it can't be used + * in both |extern "C"| and normal C++ in the same translation unit. (Alas + * |extern "C"| isn't allowed in a function.) The only affected compiler + * we really care about is gcc 4.2. For that compiler and others like it, + * we include the line number in the function name to do the best we can to + * avoid conflicts. These should be rare: a conflict would require use of + * MOZ_STATIC_ASSERT on the same line in separate files in the same + * translation unit, *and* the uses would have to be in code with + * different linkage, *and* the first observed use must be in C++-linkage + * code. + */ +# define MOZ_STATIC_ASSERT(cond, reason) \ + typedef int MOZ_STATIC_ASSERT_GLUE(moz_static_assert, __COUNTER__)[(cond) ? 1 : -1] MOZ_STATIC_ASSERT_UNUSED_ATTRIBUTE +# else +# define MOZ_STATIC_ASSERT(cond, reason) \ + extern void MOZ_STATIC_ASSERT_GLUE(moz_static_assert, __LINE__)(int arg[(cond) ? 1 : -1]) MOZ_STATIC_ASSERT_UNUSED_ATTRIBUTE +# endif + +#define MOZ_STATIC_ASSERT_IF(cond, expr, reason) MOZ_STATIC_ASSERT(!(cond) || (expr), reason) +#else +#define MOZ_STATIC_ASSERT_IF(cond, expr, reason) static_assert(!(cond) || (expr), reason) +#endif + +#ifdef __cplusplus +extern "C" { +#endif + +/* + * Prints |aStr| as an assertion failure (using aFilename and aLine as the + * location of the assertion) to the standard debug-output channel. + * + * Usually you should use MOZ_ASSERT or MOZ_CRASH instead of this method. This + * method is primarily for internal use in this header, and only secondarily + * for use in implementing release-build assertions. + */ +static MOZ_COLD MOZ_ALWAYS_INLINE void +MOZ_ReportAssertionFailure(const char* aStr, const char* aFilename, int aLine) + MOZ_PRETEND_NORETURN_FOR_STATIC_ANALYSIS +{ +#ifdef ANDROID + __android_log_print(ANDROID_LOG_FATAL, "MOZ_Assert", + "Assertion failure: %s, at %s:%d\n", + aStr, aFilename, aLine); +#else + fprintf(stderr, "Assertion failure: %s, at %s:%d\n", aStr, aFilename, aLine); +#if defined (MOZ_DUMP_ASSERTION_STACK) + nsTraceRefcnt::WalkTheStack(stderr); +#endif + fflush(stderr); +#endif +} + +static MOZ_COLD MOZ_ALWAYS_INLINE void +MOZ_ReportCrash(const char* aStr, const char* aFilename, int aLine) + MOZ_PRETEND_NORETURN_FOR_STATIC_ANALYSIS +{ +#ifdef ANDROID + __android_log_print(ANDROID_LOG_FATAL, "MOZ_CRASH", + "Hit MOZ_CRASH(%s) at %s:%d\n", aStr, aFilename, aLine); +#else + fprintf(stderr, "Hit MOZ_CRASH(%s) at %s:%d\n", aStr, aFilename, aLine); +#if defined(MOZ_DUMP_ASSERTION_STACK) + nsTraceRefcnt::WalkTheStack(stderr); +#endif + fflush(stderr); +#endif +} + +/** + * MOZ_REALLY_CRASH is used in the implementation of MOZ_CRASH(). You should + * call MOZ_CRASH instead. + */ +#if defined(_MSC_VER) + /* + * On MSVC use the __debugbreak compiler intrinsic, which produces an inline + * (not nested in a system function) breakpoint. This distinctively invokes + * Breakpad without requiring system library symbols on all stack-processing + * machines, as a nested breakpoint would require. + * + * We use TerminateProcess with the exit code aborting would generate + * because we don't want to invoke atexit handlers, destructors, library + * unload handlers, and so on when our process might be in a compromised + * state. + * + * We don't use abort() because it'd cause Windows to annoyingly pop up the + * process error dialog multiple times. See bug 345118 and bug 426163. + * + * We follow TerminateProcess() with a call to MOZ_NoReturn() so that the + * compiler doesn't hassle us to provide a return statement after a + * MOZ_REALLY_CRASH() call. + * + * (Technically these are Windows requirements, not MSVC requirements. But + * practically you need MSVC for debugging, and we only ship builds created + * by MSVC, so doing it this way reduces complexity.) + */ + +__declspec(noreturn) __inline void MOZ_NoReturn() {} + +# ifdef __cplusplus +# define MOZ_REALLY_CRASH(line) \ + do { \ + ::__debugbreak(); \ + *((volatile int*) NULL) = line; \ + ::TerminateProcess(::GetCurrentProcess(), 3); \ + ::MOZ_NoReturn(); \ + } while (0) +# else +# define MOZ_REALLY_CRASH(line) \ + do { \ + __debugbreak(); \ + *((volatile int*) NULL) = line; \ + TerminateProcess(GetCurrentProcess(), 3); \ + MOZ_NoReturn(); \ + } while (0) +# endif +#else +# ifdef __cplusplus +# define MOZ_REALLY_CRASH(line) \ + do { \ + *((volatile int*) NULL) = line; \ + ::abort(); \ + } while (0) +# else +# define MOZ_REALLY_CRASH(line) \ + do { \ + *((volatile int*) NULL) = line; \ + abort(); \ + } while (0) +# endif +#endif + +/* + * MOZ_CRASH([explanation-string]) crashes the program, plain and simple, in a + * Breakpad-compatible way, in both debug and release builds. + * + * MOZ_CRASH is a good solution for "handling" failure cases when you're + * unwilling or unable to handle them more cleanly -- for OOM, for likely memory + * corruption, and so on. It's also a good solution if you need safe behavior + * in release builds as well as debug builds. But if the failure is one that + * should be debugged and fixed, MOZ_ASSERT is generally preferable. + * + * The optional explanation-string, if provided, must be a string literal + * explaining why we're crashing. This argument is intended for use with + * MOZ_CRASH() calls whose rationale is non-obvious; don't use it if it's + * obvious why we're crashing. + * + * If we're a DEBUG build and we crash at a MOZ_CRASH which provides an + * explanation-string, we print the string to stderr. Otherwise, we don't + * print anything; this is because we want MOZ_CRASH to be 100% safe in release + * builds, and it's hard to print to stderr safely when memory might have been + * corrupted. + */ +#ifndef DEBUG +# define MOZ_CRASH(...) \ + do { \ + MOZ_CRASH_ANNOTATE("MOZ_CRASH(" __VA_ARGS__ ")"); \ + MOZ_REALLY_CRASH(__LINE__); \ + } while (0) +#else +# define MOZ_CRASH(...) \ + do { \ + MOZ_ReportCrash("" __VA_ARGS__, __FILE__, __LINE__); \ + MOZ_CRASH_ANNOTATE("MOZ_CRASH(" __VA_ARGS__ ")"); \ + MOZ_REALLY_CRASH(__LINE__); \ + } while (0) +#endif + +/* + * MOZ_CRASH_UNSAFE_OOL(explanation-string) can be used if the explanation + * string cannot be a string literal (but no other processing needs to be done + * on it). A regular MOZ_CRASH() is preferred wherever possible, as passing + * arbitrary strings from a potentially compromised process is not without risk. + * If the string being passed is the result of a printf-style function, + * consider using MOZ_CRASH_UNSAFE_PRINTF instead. + */ +#ifndef DEBUG +MFBT_API MOZ_COLD MOZ_NORETURN MOZ_NEVER_INLINE void +MOZ_CrashOOL(int aLine, const char* aReason); +# define MOZ_CRASH_UNSAFE_OOL(reason) MOZ_CrashOOL(__LINE__, reason) +#else +MFBT_API MOZ_COLD MOZ_NORETURN MOZ_NEVER_INLINE void +MOZ_CrashOOL(const char* aFilename, int aLine, const char* aReason); +# define MOZ_CRASH_UNSAFE_OOL(reason) MOZ_CrashOOL(__FILE__, __LINE__, reason) +#endif + +static const size_t sPrintfMaxArgs = 4; +static const size_t sPrintfCrashReasonSize = 1024; + +#ifndef DEBUG +MFBT_API MOZ_COLD MOZ_NORETURN MOZ_NEVER_INLINE MOZ_FORMAT_PRINTF(2, 3) void +MOZ_CrashPrintf(int aLine, const char* aFormat, ...); +# define MOZ_CALL_CRASH_PRINTF(format, ...) \ + MOZ_CrashPrintf(__LINE__, format, __VA_ARGS__) +#else +MFBT_API MOZ_COLD MOZ_NORETURN MOZ_NEVER_INLINE MOZ_FORMAT_PRINTF(3, 4) void +MOZ_CrashPrintf(const char* aFilename, int aLine, const char* aFormat, ...); +# define MOZ_CALL_CRASH_PRINTF(format, ...) \ + MOZ_CrashPrintf(__FILE__, __LINE__, format, __VA_ARGS__) +#endif + +/* + * MOZ_CRASH_UNSAFE_PRINTF(format, arg1 [, args]) can be used when more + * information is desired than a string literal can supply. The caller provides + * a printf-style format string, which must be a string literal and between + * 1 and 4 additional arguments. A regular MOZ_CRASH() is preferred wherever + * possible, as passing arbitrary strings to printf from a potentially + * compromised process is not without risk. + */ +#define MOZ_CRASH_UNSAFE_PRINTF(format, ...) \ + do { \ + MOZ_STATIC_ASSERT_VALID_ARG_COUNT(__VA_ARGS__); \ + static_assert( \ + MOZ_PASTE_PREFIX_AND_ARG_COUNT(, __VA_ARGS__) <= sPrintfMaxArgs, \ + "Only up to 4 additional arguments are allowed!"); \ + static_assert(sizeof(format) <= sPrintfCrashReasonSize, \ + "The supplied format string is too long!"); \ + MOZ_CALL_CRASH_PRINTF("" format, __VA_ARGS__); \ + } while (0) + +#ifdef __cplusplus +} /* extern "C" */ +#endif + +/* + * MOZ_ASSERT(expr [, explanation-string]) asserts that |expr| must be truthy in + * debug builds. If it is, execution continues. Otherwise, an error message + * including the expression and the explanation-string (if provided) is printed, + * an attempt is made to invoke any existing debugger, and execution halts. + * MOZ_ASSERT is fatal: no recovery is possible. Do not assert a condition + * which can correctly be falsy. + * + * The optional explanation-string, if provided, must be a string literal + * explaining the assertion. It is intended for use with assertions whose + * correctness or rationale is non-obvious, and for assertions where the "real" + * condition being tested is best described prosaically. Don't provide an + * explanation if it's not actually helpful. + * + * // No explanation needed: pointer arguments often must not be NULL. + * MOZ_ASSERT(arg); + * + * // An explanation can be helpful to explain exactly how we know an + * // assertion is valid. + * MOZ_ASSERT(state == WAITING_FOR_RESPONSE, + * "given that <thingA> and <thingB>, we must have..."); + * + * // Or it might disambiguate multiple identical (save for their location) + * // assertions of the same expression. + * MOZ_ASSERT(getSlot(PRIMITIVE_THIS_SLOT).isUndefined(), + * "we already set [[PrimitiveThis]] for this Boolean object"); + * MOZ_ASSERT(getSlot(PRIMITIVE_THIS_SLOT).isUndefined(), + * "we already set [[PrimitiveThis]] for this String object"); + * + * MOZ_ASSERT has no effect in non-debug builds. It is designed to catch bugs + * *only* during debugging, not "in the field". If you want the latter, use + * MOZ_RELEASE_ASSERT, which applies to non-debug builds as well. + * + * MOZ_DIAGNOSTIC_ASSERT works like MOZ_RELEASE_ASSERT in Nightly/Aurora and + * MOZ_ASSERT in Beta/Release - use this when a condition is potentially rare + * enough to require real user testing to hit, but is not security-sensitive. + * This can cause user pain, so use it sparingly. If a MOZ_DIAGNOSTIC_ASSERT + * is firing, it should promptly be converted to a MOZ_ASSERT while the failure + * is being investigated, rather than letting users suffer. + */ + +/* + * Implement MOZ_VALIDATE_ASSERT_CONDITION_TYPE, which is used to guard against + * accidentally passing something unintended in lieu of an assertion condition. + */ + +#ifdef __cplusplus +# include "mozilla/TypeTraits.h" +namespace mozilla { +namespace detail { + +template<typename T> +struct AssertionConditionType +{ + typedef typename RemoveReference<T>::Type ValueT; + static_assert(!IsArray<ValueT>::value, + "Expected boolean assertion condition, got an array or a " + "string!"); + static_assert(!IsFunction<ValueT>::value, + "Expected boolean assertion condition, got a function! Did " + "you intend to call that function?"); + static_assert(!IsFloatingPoint<ValueT>::value, + "It's often a bad idea to assert that a floating-point number " + "is nonzero, because such assertions tend to intermittently " + "fail. Shouldn't your code gracefully handle this case instead " + "of asserting? Anyway, if you really want to do that, write an " + "explicit boolean condition, like !!x or x!=0."); + + static const bool isValid = true; +}; + +} // namespace detail +} // namespace mozilla +# define MOZ_VALIDATE_ASSERT_CONDITION_TYPE(x) \ + static_assert(mozilla::detail::AssertionConditionType<decltype(x)>::isValid, \ + "invalid assertion condition") +#else +# define MOZ_VALIDATE_ASSERT_CONDITION_TYPE(x) +#endif + +/* First the single-argument form. */ +#define MOZ_ASSERT_HELPER1(expr) \ + do { \ + MOZ_VALIDATE_ASSERT_CONDITION_TYPE(expr); \ + if (MOZ_UNLIKELY(!MOZ_CHECK_ASSERT_ASSIGNMENT(expr))) { \ + MOZ_ReportAssertionFailure(#expr, __FILE__, __LINE__); \ + MOZ_CRASH_ANNOTATE("MOZ_RELEASE_ASSERT(" #expr ")"); \ + MOZ_REALLY_CRASH(__LINE__); \ + } \ + } while (0) +/* Now the two-argument form. */ +#define MOZ_ASSERT_HELPER2(expr, explain) \ + do { \ + MOZ_VALIDATE_ASSERT_CONDITION_TYPE(expr); \ + if (MOZ_UNLIKELY(!MOZ_CHECK_ASSERT_ASSIGNMENT(expr))) { \ + MOZ_ReportAssertionFailure(#expr " (" explain ")", __FILE__, __LINE__); \ + MOZ_CRASH_ANNOTATE("MOZ_RELEASE_ASSERT(" #expr ") (" explain ")"); \ + MOZ_REALLY_CRASH(__LINE__); \ + } \ + } while (0) + +#define MOZ_RELEASE_ASSERT_GLUE(a, b) a b +#define MOZ_RELEASE_ASSERT(...) \ + MOZ_RELEASE_ASSERT_GLUE( \ + MOZ_PASTE_PREFIX_AND_ARG_COUNT(MOZ_ASSERT_HELPER, __VA_ARGS__), \ + (__VA_ARGS__)) + +#ifdef DEBUG +# define MOZ_ASSERT(...) MOZ_RELEASE_ASSERT(__VA_ARGS__) +#else +# define MOZ_ASSERT(...) do { } while (0) +#endif /* DEBUG */ + +#ifdef RELEASE_OR_BETA +# define MOZ_DIAGNOSTIC_ASSERT MOZ_ASSERT +#else +# define MOZ_DIAGNOSTIC_ASSERT MOZ_RELEASE_ASSERT +#endif + +/* + * MOZ_ASSERT_IF(cond1, cond2) is equivalent to MOZ_ASSERT(cond2) if cond1 is + * true. + * + * MOZ_ASSERT_IF(isPrime(num), num == 2 || isOdd(num)); + * + * As with MOZ_ASSERT, MOZ_ASSERT_IF has effect only in debug builds. It is + * designed to catch bugs during debugging, not "in the field". + */ +#ifdef DEBUG +# define MOZ_ASSERT_IF(cond, expr) \ + do { \ + if (cond) { \ + MOZ_ASSERT(expr); \ + } \ + } while (0) +#else +# define MOZ_ASSERT_IF(cond, expr) do { } while (0) +#endif + +/* + * MOZ_ASSUME_UNREACHABLE_MARKER() expands to an expression which states that + * it is undefined behavior for execution to reach this point. No guarantees + * are made about what will happen if this is reached at runtime. Most code + * should use MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE because it has extra + * asserts. + */ +#if defined(__clang__) || defined(__GNUC__) +# define MOZ_ASSUME_UNREACHABLE_MARKER() __builtin_unreachable() +#elif defined(_MSC_VER) +# define MOZ_ASSUME_UNREACHABLE_MARKER() __assume(0) +#else +# ifdef __cplusplus +# define MOZ_ASSUME_UNREACHABLE_MARKER() ::abort() +# else +# define MOZ_ASSUME_UNREACHABLE_MARKER() abort() +# endif +#endif + +/* + * MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE([reason]) tells the compiler that it + * can assume that the macro call cannot be reached during execution. This lets + * the compiler generate better-optimized code under some circumstances, at the + * expense of the program's behavior being undefined if control reaches the + * MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE. + * + * In Gecko, you probably should not use this macro outside of performance- or + * size-critical code, because it's unsafe. If you don't care about code size + * or performance, you should probably use MOZ_ASSERT or MOZ_CRASH. + * + * SpiderMonkey is a different beast, and there it's acceptable to use + * MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE more widely. + * + * Note that MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE is noreturn, so it's valid + * not to return a value following a MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE + * call. + * + * Example usage: + * + * enum ValueType { + * VALUE_STRING, + * VALUE_INT, + * VALUE_FLOAT + * }; + * + * int ptrToInt(ValueType type, void* value) { + * { + * // We know for sure that type is either INT or FLOAT, and we want this + * // code to run as quickly as possible. + * switch (type) { + * case VALUE_INT: + * return *(int*) value; + * case VALUE_FLOAT: + * return (int) *(float*) value; + * default: + * MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE("Unexpected ValueType"); + * } + * } + */ + +/* + * Unconditional assert in debug builds for (assumed) unreachable code paths + * that have a safe return without crashing in release builds. + */ +#define MOZ_ASSERT_UNREACHABLE(reason) \ + MOZ_ASSERT(false, "MOZ_ASSERT_UNREACHABLE: " reason) + +#define MOZ_MAKE_COMPILER_ASSUME_IS_UNREACHABLE(reason) \ + do { \ + MOZ_ASSERT_UNREACHABLE(reason); \ + MOZ_ASSUME_UNREACHABLE_MARKER(); \ + } while (0) + +/** + * MOZ_FALLTHROUGH_ASSERT is an annotation to suppress compiler warnings about + * switch cases that MOZ_ASSERT(false) (or its alias MOZ_ASSERT_UNREACHABLE) in + * debug builds, but intentionally fall through in release builds to handle + * unexpected values. + * + * Why do we need MOZ_FALLTHROUGH_ASSERT in addition to MOZ_FALLTHROUGH? In + * release builds, the MOZ_ASSERT(false) will expand to `do { } while (0)`, + * requiring a MOZ_FALLTHROUGH annotation to suppress a -Wimplicit-fallthrough + * warning. In debug builds, the MOZ_ASSERT(false) will expand to something like + * `if (true) { MOZ_CRASH(); }` and the MOZ_FALLTHROUGH annotation will cause + * a -Wunreachable-code warning. The MOZ_FALLTHROUGH_ASSERT macro breaks this + * warning stalemate. + * + * // Example before MOZ_FALLTHROUGH_ASSERT: + * switch (foo) { + * default: + * // This case wants to assert in debug builds, fall through in release. + * MOZ_ASSERT(false); // -Wimplicit-fallthrough warning in release builds! + * MOZ_FALLTHROUGH; // but -Wunreachable-code warning in debug builds! + * case 5: + * return 5; + * } + * + * // Example with MOZ_FALLTHROUGH_ASSERT: + * switch (foo) { + * default: + * // This case asserts in debug builds, falls through in release. + * MOZ_FALLTHROUGH_ASSERT("Unexpected foo value?!"); + * case 5: + * return 5; + * } + */ +#ifdef DEBUG +# define MOZ_FALLTHROUGH_ASSERT(reason) MOZ_CRASH("MOZ_FALLTHROUGH_ASSERT: " reason) +#else +# define MOZ_FALLTHROUGH_ASSERT(...) MOZ_FALLTHROUGH +#endif + +/* + * MOZ_ALWAYS_TRUE(expr) and MOZ_ALWAYS_FALSE(expr) always evaluate the provided + * expression, in debug builds and in release builds both. Then, in debug + * builds only, the value of the expression is asserted either true or false + * using MOZ_ASSERT. + */ +#ifdef DEBUG +# define MOZ_ALWAYS_TRUE(expr) \ + do { \ + if ((expr)) { \ + /* Do nothing. */ \ + } else { \ + MOZ_ASSERT(false, #expr); \ + } \ + } while (0) +# define MOZ_ALWAYS_FALSE(expr) \ + do { \ + if ((expr)) { \ + MOZ_ASSERT(false, #expr); \ + } else { \ + /* Do nothing. */ \ + } \ + } while (0) +#else +# define MOZ_ALWAYS_TRUE(expr) \ + do { \ + if ((expr)) { \ + /* Silence MOZ_MUST_USE. */ \ + } \ + } while (0) +# define MOZ_ALWAYS_FALSE(expr) \ + do { \ + if ((expr)) { \ + /* Silence MOZ_MUST_USE. */ \ + } \ + } while (0) +#endif + +#undef MOZ_DUMP_ASSERTION_STACK +#undef MOZ_CRASH_CRASHREPORT + +#endif /* mozilla_Assertions_h */ diff --git a/mfbt/Atomics.h b/mfbt/Atomics.h new file mode 100644 index 000000000..213d1b9f0 --- /dev/null +++ b/mfbt/Atomics.h @@ -0,0 +1,800 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* + * Implements (almost always) lock-free atomic operations. The operations here + * are a subset of that which can be found in C++11's <atomic> header, with a + * different API to enforce consistent memory ordering constraints. + * + * Anyone caught using |volatile| for inter-thread memory safety needs to be + * sent a copy of this header and the C++11 standard. + */ + +#ifndef mozilla_Atomics_h +#define mozilla_Atomics_h + +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" +#include "mozilla/Compiler.h" +#include "mozilla/TypeTraits.h" + +#include <stdint.h> + +/* + * Our minimum deployment target on clang/OS X is OS X 10.6, whose SDK + * does not have <atomic>. So be sure to check for <atomic> support + * along with C++0x support. + */ +#if defined(_MSC_VER) +# define MOZ_HAVE_CXX11_ATOMICS +#elif defined(__clang__) || defined(__GNUC__) + /* + * Clang doesn't like <atomic> from libstdc++ before 4.7 due to the + * loose typing of the atomic builtins. GCC 4.5 and 4.6 lacks inline + * definitions for unspecialized std::atomic and causes linking errors. + * Therefore, we require at least 4.7.0 for using libstdc++. + * + * libc++ <atomic> is only functional with clang. + */ +# if MOZ_USING_LIBSTDCXX && MOZ_LIBSTDCXX_VERSION_AT_LEAST(4, 7, 0) +# define MOZ_HAVE_CXX11_ATOMICS +# elif MOZ_USING_LIBCXX && defined(__clang__) +# define MOZ_HAVE_CXX11_ATOMICS +# endif +#endif + +namespace mozilla { + +/** + * An enum of memory ordering possibilities for atomics. + * + * Memory ordering is the observable state of distinct values in memory. + * (It's a separate concept from atomicity, which concerns whether an + * operation can ever be observed in an intermediate state. Don't + * conflate the two!) Given a sequence of operations in source code on + * memory, it is *not* always the case that, at all times and on all + * cores, those operations will appear to have occurred in that exact + * sequence. First, the compiler might reorder that sequence, if it + * thinks another ordering will be more efficient. Second, the CPU may + * not expose so consistent a view of memory. CPUs will often perform + * their own instruction reordering, above and beyond that performed by + * the compiler. And each core has its own memory caches, and accesses + * (reads and writes both) to "memory" may only resolve to out-of-date + * cache entries -- not to the "most recently" performed operation in + * some global sense. Any access to a value that may be used by + * multiple threads, potentially across multiple cores, must therefore + * have a memory ordering imposed on it, for all code on all + * threads/cores to have a sufficiently coherent worldview. + * + * http://gcc.gnu.org/wiki/Atomic/GCCMM/AtomicSync and + * http://en.cppreference.com/w/cpp/atomic/memory_order go into more + * detail on all this, including examples of how each mode works. + * + * Note that for simplicity and practicality, not all of the modes in + * C++11 are supported. The missing C++11 modes are either subsumed by + * the modes we provide below, or not relevant for the CPUs we support + * in Gecko. These three modes are confusing enough as it is! + */ +enum MemoryOrdering { + /* + * Relaxed ordering is the simplest memory ordering: none at all. + * When the result of a write is observed, nothing may be inferred + * about other memory. Writes ostensibly performed "before" on the + * writing thread may not yet be visible. Writes performed "after" on + * the writing thread may already be visible, if the compiler or CPU + * reordered them. (The latter can happen if reads and/or writes get + * held up in per-processor caches.) Relaxed ordering means + * operations can always use cached values (as long as the actual + * updates to atomic values actually occur, correctly, eventually), so + * it's usually the fastest sort of atomic access. For this reason, + * *it's also the most dangerous kind of access*. + * + * Relaxed ordering is good for things like process-wide statistics + * counters that don't need to be consistent with anything else, so + * long as updates themselves are atomic. (And so long as any + * observations of that value can tolerate being out-of-date -- if you + * need some sort of up-to-date value, you need some sort of other + * synchronizing operation.) It's *not* good for locks, mutexes, + * reference counts, etc. that mediate access to other memory, or must + * be observably consistent with other memory. + * + * x86 architectures don't take advantage of the optimization + * opportunities that relaxed ordering permits. Thus it's possible + * that using relaxed ordering will "work" on x86 but fail elsewhere + * (ARM, say, which *does* implement non-sequentially-consistent + * relaxed ordering semantics). Be extra-careful using relaxed + * ordering if you can't easily test non-x86 architectures! + */ + Relaxed, + + /* + * When an atomic value is updated with ReleaseAcquire ordering, and + * that new value is observed with ReleaseAcquire ordering, prior + * writes (atomic or not) are also observable. What ReleaseAcquire + * *doesn't* give you is any observable ordering guarantees for + * ReleaseAcquire-ordered operations on different objects. For + * example, if there are two cores that each perform ReleaseAcquire + * operations on separate objects, each core may or may not observe + * the operations made by the other core. The only way the cores can + * be synchronized with ReleaseAcquire is if they both + * ReleaseAcquire-access the same object. This implies that you can't + * necessarily describe some global total ordering of ReleaseAcquire + * operations. + * + * ReleaseAcquire ordering is good for (as the name implies) atomic + * operations on values controlling ownership of things: reference + * counts, mutexes, and the like. However, if you are thinking about + * using these to implement your own locks or mutexes, you should take + * a good, hard look at actual lock or mutex primitives first. + */ + ReleaseAcquire, + + /* + * When an atomic value is updated with SequentiallyConsistent + * ordering, all writes observable when the update is observed, just + * as with ReleaseAcquire ordering. But, furthermore, a global total + * ordering of SequentiallyConsistent operations *can* be described. + * For example, if two cores perform SequentiallyConsistent operations + * on separate objects, one core will observably perform its update + * (and all previous operations will have completed), then the other + * core will observably perform its update (and all previous + * operations will have completed). (Although those previous + * operations aren't themselves ordered -- they could be intermixed, + * or ordered if they occur on atomic values with ordering + * requirements.) SequentiallyConsistent is the *simplest and safest* + * ordering of atomic operations -- it's always as if one operation + * happens, then another, then another, in some order -- and every + * core observes updates to happen in that single order. Because it + * has the most synchronization requirements, operations ordered this + * way also tend to be slowest. + * + * SequentiallyConsistent ordering can be desirable when multiple + * threads observe objects, and they all have to agree on the + * observable order of changes to them. People expect + * SequentiallyConsistent ordering, even if they shouldn't, when + * writing code, atomic or otherwise. SequentiallyConsistent is also + * the ordering of choice when designing lockless data structures. If + * you don't know what order to use, use this one. + */ + SequentiallyConsistent, +}; + +} // namespace mozilla + +// Build up the underlying intrinsics. +#ifdef MOZ_HAVE_CXX11_ATOMICS + +# include <atomic> + +namespace mozilla { +namespace detail { + +/* + * We provide CompareExchangeFailureOrder to work around a bug in some + * versions of GCC's <atomic> header. See bug 898491. + */ +template<MemoryOrdering Order> struct AtomicOrderConstraints; + +template<> +struct AtomicOrderConstraints<Relaxed> +{ + static const std::memory_order AtomicRMWOrder = std::memory_order_relaxed; + static const std::memory_order LoadOrder = std::memory_order_relaxed; + static const std::memory_order StoreOrder = std::memory_order_relaxed; + static const std::memory_order CompareExchangeFailureOrder = + std::memory_order_relaxed; +}; + +template<> +struct AtomicOrderConstraints<ReleaseAcquire> +{ + static const std::memory_order AtomicRMWOrder = std::memory_order_acq_rel; + static const std::memory_order LoadOrder = std::memory_order_acquire; + static const std::memory_order StoreOrder = std::memory_order_release; + static const std::memory_order CompareExchangeFailureOrder = + std::memory_order_acquire; +}; + +template<> +struct AtomicOrderConstraints<SequentiallyConsistent> +{ + static const std::memory_order AtomicRMWOrder = std::memory_order_seq_cst; + static const std::memory_order LoadOrder = std::memory_order_seq_cst; + static const std::memory_order StoreOrder = std::memory_order_seq_cst; + static const std::memory_order CompareExchangeFailureOrder = + std::memory_order_seq_cst; +}; + +template<typename T, MemoryOrdering Order> +struct IntrinsicBase +{ + typedef std::atomic<T> ValueType; + typedef AtomicOrderConstraints<Order> OrderedOp; +}; + +template<typename T, MemoryOrdering Order> +struct IntrinsicMemoryOps : public IntrinsicBase<T, Order> +{ + typedef IntrinsicBase<T, Order> Base; + + static T load(const typename Base::ValueType& aPtr) + { + return aPtr.load(Base::OrderedOp::LoadOrder); + } + + static void store(typename Base::ValueType& aPtr, T aVal) + { + aPtr.store(aVal, Base::OrderedOp::StoreOrder); + } + + static T exchange(typename Base::ValueType& aPtr, T aVal) + { + return aPtr.exchange(aVal, Base::OrderedOp::AtomicRMWOrder); + } + + static bool compareExchange(typename Base::ValueType& aPtr, + T aOldVal, T aNewVal) + { + return aPtr.compare_exchange_strong(aOldVal, aNewVal, + Base::OrderedOp::AtomicRMWOrder, + Base::OrderedOp::CompareExchangeFailureOrder); + } +}; + +template<typename T, MemoryOrdering Order> +struct IntrinsicAddSub : public IntrinsicBase<T, Order> +{ + typedef IntrinsicBase<T, Order> Base; + + static T add(typename Base::ValueType& aPtr, T aVal) + { + return aPtr.fetch_add(aVal, Base::OrderedOp::AtomicRMWOrder); + } + + static T sub(typename Base::ValueType& aPtr, T aVal) + { + return aPtr.fetch_sub(aVal, Base::OrderedOp::AtomicRMWOrder); + } +}; + +template<typename T, MemoryOrdering Order> +struct IntrinsicAddSub<T*, Order> : public IntrinsicBase<T*, Order> +{ + typedef IntrinsicBase<T*, Order> Base; + + static T* add(typename Base::ValueType& aPtr, ptrdiff_t aVal) + { + return aPtr.fetch_add(aVal, Base::OrderedOp::AtomicRMWOrder); + } + + static T* sub(typename Base::ValueType& aPtr, ptrdiff_t aVal) + { + return aPtr.fetch_sub(aVal, Base::OrderedOp::AtomicRMWOrder); + } +}; + +template<typename T, MemoryOrdering Order> +struct IntrinsicIncDec : public IntrinsicAddSub<T, Order> +{ + typedef IntrinsicBase<T, Order> Base; + + static T inc(typename Base::ValueType& aPtr) + { + return IntrinsicAddSub<T, Order>::add(aPtr, 1); + } + + static T dec(typename Base::ValueType& aPtr) + { + return IntrinsicAddSub<T, Order>::sub(aPtr, 1); + } +}; + +template<typename T, MemoryOrdering Order> +struct AtomicIntrinsics : public IntrinsicMemoryOps<T, Order>, + public IntrinsicIncDec<T, Order> +{ + typedef IntrinsicBase<T, Order> Base; + + static T or_(typename Base::ValueType& aPtr, T aVal) + { + return aPtr.fetch_or(aVal, Base::OrderedOp::AtomicRMWOrder); + } + + static T xor_(typename Base::ValueType& aPtr, T aVal) + { + return aPtr.fetch_xor(aVal, Base::OrderedOp::AtomicRMWOrder); + } + + static T and_(typename Base::ValueType& aPtr, T aVal) + { + return aPtr.fetch_and(aVal, Base::OrderedOp::AtomicRMWOrder); + } +}; + +template<typename T, MemoryOrdering Order> +struct AtomicIntrinsics<T*, Order> + : public IntrinsicMemoryOps<T*, Order>, public IntrinsicIncDec<T*, Order> +{ +}; + +template<typename T> +struct ToStorageTypeArgument +{ + static constexpr T convert (T aT) { return aT; } +}; + +} // namespace detail +} // namespace mozilla + +#elif defined(__GNUC__) + +namespace mozilla { +namespace detail { + +/* + * The __sync_* family of intrinsics is documented here: + * + * http://gcc.gnu.org/onlinedocs/gcc-4.6.4/gcc/Atomic-Builtins.html + * + * While these intrinsics are deprecated in favor of the newer __atomic_* + * family of intrincs: + * + * http://gcc.gnu.org/onlinedocs/gcc-4.7.3/gcc/_005f_005fatomic-Builtins.html + * + * any GCC version that supports the __atomic_* intrinsics will also support + * the <atomic> header and so will be handled above. We provide a version of + * atomics using the __sync_* intrinsics to support older versions of GCC. + * + * All __sync_* intrinsics that we use below act as full memory barriers, for + * both compiler and hardware reordering, except for __sync_lock_test_and_set, + * which is a only an acquire barrier. When we call __sync_lock_test_and_set, + * we add a barrier above it as appropriate. + */ + +template<MemoryOrdering Order> struct Barrier; + +/* + * Some processors (in particular, x86) don't require quite so many calls to + * __sync_sychronize as our specializations of Barrier produce. If + * performance turns out to be an issue, defining these specializations + * on a per-processor basis would be a good first tuning step. + */ + +template<> +struct Barrier<Relaxed> +{ + static void beforeLoad() {} + static void afterLoad() {} + static void beforeStore() {} + static void afterStore() {} +}; + +template<> +struct Barrier<ReleaseAcquire> +{ + static void beforeLoad() {} + static void afterLoad() { __sync_synchronize(); } + static void beforeStore() { __sync_synchronize(); } + static void afterStore() {} +}; + +template<> +struct Barrier<SequentiallyConsistent> +{ + static void beforeLoad() { __sync_synchronize(); } + static void afterLoad() { __sync_synchronize(); } + static void beforeStore() { __sync_synchronize(); } + static void afterStore() { __sync_synchronize(); } +}; + +template<typename T, bool TIsEnum = IsEnum<T>::value> +struct AtomicStorageType +{ + // For non-enums, just use the type directly. + typedef T Type; +}; + +template<typename T> +struct AtomicStorageType<T, true> + : Conditional<sizeof(T) == 4, uint32_t, uint64_t> +{ + static_assert(sizeof(T) == 4 || sizeof(T) == 8, + "wrong type computed in conditional above"); +}; + +template<typename T, MemoryOrdering Order> +struct IntrinsicMemoryOps +{ + typedef typename AtomicStorageType<T>::Type ValueType; + + static T load(const ValueType& aPtr) + { + Barrier<Order>::beforeLoad(); + T val = T(aPtr); + Barrier<Order>::afterLoad(); + return val; + } + + static void store(ValueType& aPtr, T aVal) + { + Barrier<Order>::beforeStore(); + aPtr = ValueType(aVal); + Barrier<Order>::afterStore(); + } + + static T exchange(ValueType& aPtr, T aVal) + { + // __sync_lock_test_and_set is only an acquire barrier; loads and stores + // can't be moved up from after to before it, but they can be moved down + // from before to after it. We may want a stricter ordering, so we need + // an explicit barrier. + Barrier<Order>::beforeStore(); + return T(__sync_lock_test_and_set(&aPtr, ValueType(aVal))); + } + + static bool compareExchange(ValueType& aPtr, T aOldVal, T aNewVal) + { + return __sync_bool_compare_and_swap(&aPtr, ValueType(aOldVal), ValueType(aNewVal)); + } +}; + +template<typename T, MemoryOrdering Order> +struct IntrinsicAddSub + : public IntrinsicMemoryOps<T, Order> +{ + typedef IntrinsicMemoryOps<T, Order> Base; + typedef typename Base::ValueType ValueType; + + static T add(ValueType& aPtr, T aVal) + { + return T(__sync_fetch_and_add(&aPtr, ValueType(aVal))); + } + + static T sub(ValueType& aPtr, T aVal) + { + return T(__sync_fetch_and_sub(&aPtr, ValueType(aVal))); + } +}; + +template<typename T, MemoryOrdering Order> +struct IntrinsicAddSub<T*, Order> + : public IntrinsicMemoryOps<T*, Order> +{ + typedef IntrinsicMemoryOps<T*, Order> Base; + typedef typename Base::ValueType ValueType; + + /* + * The reinterpret_casts are needed so that + * __sync_fetch_and_{add,sub} will properly type-check. + * + * Also, these functions do not provide standard semantics for + * pointer types, so we need to adjust the addend. + */ + static ValueType add(ValueType& aPtr, ptrdiff_t aVal) + { + ValueType amount = reinterpret_cast<ValueType>(aVal * sizeof(T)); + return __sync_fetch_and_add(&aPtr, amount); + } + + static ValueType sub(ValueType& aPtr, ptrdiff_t aVal) + { + ValueType amount = reinterpret_cast<ValueType>(aVal * sizeof(T)); + return __sync_fetch_and_sub(&aPtr, amount); + } +}; + +template<typename T, MemoryOrdering Order> +struct IntrinsicIncDec : public IntrinsicAddSub<T, Order> +{ + typedef IntrinsicAddSub<T, Order> Base; + typedef typename Base::ValueType ValueType; + + static T inc(ValueType& aPtr) { return Base::add(aPtr, 1); } + static T dec(ValueType& aPtr) { return Base::sub(aPtr, 1); } +}; + +template<typename T, MemoryOrdering Order> +struct AtomicIntrinsics : public IntrinsicIncDec<T, Order> +{ + static T or_( T& aPtr, T aVal) { return __sync_fetch_and_or(&aPtr, aVal); } + static T xor_(T& aPtr, T aVal) { return __sync_fetch_and_xor(&aPtr, aVal); } + static T and_(T& aPtr, T aVal) { return __sync_fetch_and_and(&aPtr, aVal); } +}; + +template<typename T, MemoryOrdering Order> +struct AtomicIntrinsics<T*, Order> : public IntrinsicIncDec<T*, Order> +{ +}; + +template<typename T, bool TIsEnum = IsEnum<T>::value> +struct ToStorageTypeArgument +{ + typedef typename AtomicStorageType<T>::Type ResultType; + + static constexpr ResultType convert (T aT) { return ResultType(aT); } +}; + +template<typename T> +struct ToStorageTypeArgument<T, false> +{ + static constexpr T convert (T aT) { return aT; } +}; + +} // namespace detail +} // namespace mozilla + +#else +# error "Atomic compiler intrinsics are not supported on your platform" +#endif + +namespace mozilla { + +namespace detail { + +template<typename T, MemoryOrdering Order> +class AtomicBase +{ + static_assert(sizeof(T) == 4 || sizeof(T) == 8, + "mozilla/Atomics.h only supports 32-bit and 64-bit types"); + +protected: + typedef typename detail::AtomicIntrinsics<T, Order> Intrinsics; + typedef typename Intrinsics::ValueType ValueType; + ValueType mValue; + +public: + constexpr AtomicBase() : mValue() {} + explicit constexpr AtomicBase(T aInit) + : mValue(ToStorageTypeArgument<T>::convert(aInit)) + {} + + // Note: we can't provide operator T() here because Atomic<bool> inherits + // from AtomcBase with T=uint32_t and not T=bool. If we implemented + // operator T() here, it would cause errors when comparing Atomic<bool> with + // a regular bool. + + T operator=(T aVal) + { + Intrinsics::store(mValue, aVal); + return aVal; + } + + /** + * Performs an atomic swap operation. aVal is stored and the previous + * value of this variable is returned. + */ + T exchange(T aVal) + { + return Intrinsics::exchange(mValue, aVal); + } + + /** + * Performs an atomic compare-and-swap operation and returns true if it + * succeeded. This is equivalent to atomically doing + * + * if (mValue == aOldValue) { + * mValue = aNewValue; + * return true; + * } else { + * return false; + * } + */ + bool compareExchange(T aOldValue, T aNewValue) + { + return Intrinsics::compareExchange(mValue, aOldValue, aNewValue); + } + +private: + template<MemoryOrdering AnyOrder> + AtomicBase(const AtomicBase<T, AnyOrder>& aCopy) = delete; +}; + +template<typename T, MemoryOrdering Order> +class AtomicBaseIncDec : public AtomicBase<T, Order> +{ + typedef typename detail::AtomicBase<T, Order> Base; + +public: + constexpr AtomicBaseIncDec() : Base() {} + explicit constexpr AtomicBaseIncDec(T aInit) : Base(aInit) {} + + using Base::operator=; + + operator T() const { return Base::Intrinsics::load(Base::mValue); } + T operator++(int) { return Base::Intrinsics::inc(Base::mValue); } + T operator--(int) { return Base::Intrinsics::dec(Base::mValue); } + T operator++() { return Base::Intrinsics::inc(Base::mValue) + 1; } + T operator--() { return Base::Intrinsics::dec(Base::mValue) - 1; } + +private: + template<MemoryOrdering AnyOrder> + AtomicBaseIncDec(const AtomicBaseIncDec<T, AnyOrder>& aCopy) = delete; +}; + +} // namespace detail + +/** + * A wrapper for a type that enforces that all memory accesses are atomic. + * + * In general, where a variable |T foo| exists, |Atomic<T> foo| can be used in + * its place. Implementations for integral and pointer types are provided + * below. + * + * Atomic accesses are sequentially consistent by default. You should + * use the default unless you are tall enough to ride the + * memory-ordering roller coaster (if you're not sure, you aren't) and + * you have a compelling reason to do otherwise. + * + * There is one exception to the case of atomic memory accesses: providing an + * initial value of the atomic value is not guaranteed to be atomic. This is a + * deliberate design choice that enables static atomic variables to be declared + * without introducing extra static constructors. + */ +template<typename T, + MemoryOrdering Order = SequentiallyConsistent, + typename Enable = void> +class Atomic; + +/** + * Atomic<T> implementation for integral types. + * + * In addition to atomic store and load operations, compound assignment and + * increment/decrement operators are implemented which perform the + * corresponding read-modify-write operation atomically. Finally, an atomic + * swap method is provided. + */ +template<typename T, MemoryOrdering Order> +class Atomic<T, Order, typename EnableIf<IsIntegral<T>::value && + !IsSame<T, bool>::value>::Type> + : public detail::AtomicBaseIncDec<T, Order> +{ + typedef typename detail::AtomicBaseIncDec<T, Order> Base; + +public: + constexpr Atomic() : Base() {} + explicit constexpr Atomic(T aInit) : Base(aInit) {} + + using Base::operator=; + + T operator+=(T aDelta) + { + return Base::Intrinsics::add(Base::mValue, aDelta) + aDelta; + } + + T operator-=(T aDelta) + { + return Base::Intrinsics::sub(Base::mValue, aDelta) - aDelta; + } + + T operator|=(T aVal) + { + return Base::Intrinsics::or_(Base::mValue, aVal) | aVal; + } + + T operator^=(T aVal) + { + return Base::Intrinsics::xor_(Base::mValue, aVal) ^ aVal; + } + + T operator&=(T aVal) + { + return Base::Intrinsics::and_(Base::mValue, aVal) & aVal; + } + +private: + Atomic(Atomic<T, Order>& aOther) = delete; +}; + +/** + * Atomic<T> implementation for pointer types. + * + * An atomic compare-and-swap primitive for pointer variables is provided, as + * are atomic increment and decement operators. Also provided are the compound + * assignment operators for addition and subtraction. Atomic swap (via + * exchange()) is included as well. + */ +template<typename T, MemoryOrdering Order> +class Atomic<T*, Order> : public detail::AtomicBaseIncDec<T*, Order> +{ + typedef typename detail::AtomicBaseIncDec<T*, Order> Base; + +public: + constexpr Atomic() : Base() {} + explicit constexpr Atomic(T* aInit) : Base(aInit) {} + + using Base::operator=; + + T* operator+=(ptrdiff_t aDelta) + { + return Base::Intrinsics::add(Base::mValue, aDelta) + aDelta; + } + + T* operator-=(ptrdiff_t aDelta) + { + return Base::Intrinsics::sub(Base::mValue, aDelta) - aDelta; + } + +private: + Atomic(Atomic<T*, Order>& aOther) = delete; +}; + +/** + * Atomic<T> implementation for enum types. + * + * The atomic store and load operations and the atomic swap method is provided. + */ +template<typename T, MemoryOrdering Order> +class Atomic<T, Order, typename EnableIf<IsEnum<T>::value>::Type> + : public detail::AtomicBase<T, Order> +{ + typedef typename detail::AtomicBase<T, Order> Base; + +public: + constexpr Atomic() : Base() {} + explicit constexpr Atomic(T aInit) : Base(aInit) {} + + operator T() const { return T(Base::Intrinsics::load(Base::mValue)); } + + using Base::operator=; + +private: + Atomic(Atomic<T, Order>& aOther) = delete; +}; + +/** + * Atomic<T> implementation for boolean types. + * + * The atomic store and load operations and the atomic swap method is provided. + * + * Note: + * + * - sizeof(Atomic<bool>) != sizeof(bool) for some implementations of + * bool and/or some implementations of std::atomic. This is allowed in + * [atomic.types.generic]p9. + * + * - It's not obvious whether the 8-bit atomic functions on Windows are always + * inlined or not. If they are not inlined, the corresponding functions in the + * runtime library are not available on Windows XP. This is why we implement + * Atomic<bool> with an underlying type of uint32_t. + */ +template<MemoryOrdering Order> +class Atomic<bool, Order> + : protected detail::AtomicBase<uint32_t, Order> +{ + typedef typename detail::AtomicBase<uint32_t, Order> Base; + +public: + constexpr Atomic() : Base() {} + explicit constexpr Atomic(bool aInit) : Base(aInit) {} + + // We provide boolean wrappers for the underlying AtomicBase methods. + MOZ_IMPLICIT operator bool() const + { + return Base::Intrinsics::load(Base::mValue); + } + + bool operator=(bool aVal) + { + return Base::operator=(aVal); + } + + bool exchange(bool aVal) + { + return Base::exchange(aVal); + } + + bool compareExchange(bool aOldValue, bool aNewValue) + { + return Base::compareExchange(aOldValue, aNewValue); + } + +private: + Atomic(Atomic<bool, Order>& aOther) = delete; +}; + +} // namespace mozilla + +#endif /* mozilla_Atomics_h */ diff --git a/mfbt/Attributes.h b/mfbt/Attributes.h new file mode 100644 index 000000000..df6172f31 --- /dev/null +++ b/mfbt/Attributes.h @@ -0,0 +1,604 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Implementations of various class and method modifier attributes. */ + +#ifndef mozilla_Attributes_h +#define mozilla_Attributes_h + +#include "mozilla/Compiler.h" + +/* + * MOZ_ALWAYS_INLINE is a macro which expands to tell the compiler that the + * method decorated with it must be inlined, even if the compiler thinks + * otherwise. This is only a (much) stronger version of the inline hint: + * compilers are not guaranteed to respect it (although they're much more likely + * to do so). + * + * The MOZ_ALWAYS_INLINE_EVEN_DEBUG macro is yet stronger. It tells the + * compiler to inline even in DEBUG builds. It should be used very rarely. + */ +#if defined(_MSC_VER) +# define MOZ_ALWAYS_INLINE_EVEN_DEBUG __forceinline +#elif defined(__GNUC__) +# define MOZ_ALWAYS_INLINE_EVEN_DEBUG __attribute__((always_inline)) inline +#else +# define MOZ_ALWAYS_INLINE_EVEN_DEBUG inline +#endif + +#if !defined(DEBUG) +# define MOZ_ALWAYS_INLINE MOZ_ALWAYS_INLINE_EVEN_DEBUG +#elif defined(_MSC_VER) && !defined(__cplusplus) +# define MOZ_ALWAYS_INLINE __inline +#else +# define MOZ_ALWAYS_INLINE inline +#endif + +#if defined(_MSC_VER) +/* + * g++ requires -std=c++0x or -std=gnu++0x to support C++11 functionality + * without warnings (functionality used by the macros below). These modes are + * detectable by checking whether __GXX_EXPERIMENTAL_CXX0X__ is defined or, more + * standardly, by checking whether __cplusplus has a C++11 or greater value. + * Current versions of g++ do not correctly set __cplusplus, so we check both + * for forward compatibility. + */ +# define MOZ_HAVE_NEVER_INLINE __declspec(noinline) +# define MOZ_HAVE_NORETURN __declspec(noreturn) +#elif defined(__clang__) + /* + * Per Clang documentation, "Note that marketing version numbers should not + * be used to check for language features, as different vendors use different + * numbering schemes. Instead, use the feature checking macros." + */ +# ifndef __has_extension +# define __has_extension __has_feature /* compatibility, for older versions of clang */ +# endif +# if __has_attribute(noinline) +# define MOZ_HAVE_NEVER_INLINE __attribute__((noinline)) +# endif +# if __has_attribute(noreturn) +# define MOZ_HAVE_NORETURN __attribute__((noreturn)) +# endif +#elif defined(__GNUC__) +# define MOZ_HAVE_NEVER_INLINE __attribute__((noinline)) +# define MOZ_HAVE_NORETURN __attribute__((noreturn)) +#endif + +/* + * When built with clang analyzer (a.k.a scan-build), define MOZ_HAVE_NORETURN + * to mark some false positives + */ +#ifdef __clang_analyzer__ +# if __has_extension(attribute_analyzer_noreturn) +# define MOZ_HAVE_ANALYZER_NORETURN __attribute__((analyzer_noreturn)) +# endif +#endif + +/* + * MOZ_NEVER_INLINE is a macro which expands to tell the compiler that the + * method decorated with it must never be inlined, even if the compiler would + * otherwise choose to inline the method. Compilers aren't absolutely + * guaranteed to support this, but most do. + */ +#if defined(MOZ_HAVE_NEVER_INLINE) +# define MOZ_NEVER_INLINE MOZ_HAVE_NEVER_INLINE +#else +# define MOZ_NEVER_INLINE /* no support */ +#endif + +/* + * MOZ_NORETURN, specified at the start of a function declaration, indicates + * that the given function does not return. (The function definition does not + * need to be annotated.) + * + * MOZ_NORETURN void abort(const char* msg); + * + * This modifier permits the compiler to optimize code assuming a call to such a + * function will never return. It also enables the compiler to avoid spurious + * warnings about not initializing variables, or about any other seemingly-dodgy + * operations performed after the function returns. + * + * This modifier does not affect the corresponding function's linking behavior. + */ +#if defined(MOZ_HAVE_NORETURN) +# define MOZ_NORETURN MOZ_HAVE_NORETURN +#else +# define MOZ_NORETURN /* no support */ +#endif + +/** + * MOZ_COLD tells the compiler that a function is "cold", meaning infrequently + * executed. This may lead it to optimize for size more aggressively than speed, + * or to allocate the body of the function in a distant part of the text segment + * to help keep it from taking up unnecessary icache when it isn't in use. + * + * Place this attribute at the very beginning of a function definition. For + * example, write + * + * MOZ_COLD int foo(); + * + * or + * + * MOZ_COLD int foo() { return 42; } + */ +#if defined(__GNUC__) || defined(__clang__) +# define MOZ_COLD __attribute__ ((cold)) +#else +# define MOZ_COLD +#endif + +/** + * MOZ_NONNULL tells the compiler that some of the arguments to a function are + * known to be non-null. The arguments are a list of 1-based argument indexes + * identifying arguments which are known to be non-null. + * + * Place this attribute at the very beginning of a function definition. For + * example, write + * + * MOZ_NONNULL(1, 2) int foo(char *p, char *q); + */ +#if defined(__GNUC__) || defined(__clang__) +# define MOZ_NONNULL(...) __attribute__ ((nonnull(__VA_ARGS__))) +#else +# define MOZ_NONNULL(...) +#endif + +/* + * MOZ_PRETEND_NORETURN_FOR_STATIC_ANALYSIS, specified at the end of a function + * declaration, indicates that for the purposes of static analysis, this + * function does not return. (The function definition does not need to be + * annotated.) + * + * MOZ_ReportCrash(const char* s, const char* file, int ln) + * MOZ_PRETEND_NORETURN_FOR_STATIC_ANALYSIS + * + * Some static analyzers, like scan-build from clang, can use this information + * to eliminate false positives. From the upstream documentation of scan-build: + * "This attribute is useful for annotating assertion handlers that actually + * can return, but for the purpose of using the analyzer we want to pretend + * that such functions do not return." + * + */ +#if defined(MOZ_HAVE_ANALYZER_NORETURN) +# define MOZ_PRETEND_NORETURN_FOR_STATIC_ANALYSIS MOZ_HAVE_ANALYZER_NORETURN +#else +# define MOZ_PRETEND_NORETURN_FOR_STATIC_ANALYSIS /* no support */ +#endif + +/* + * MOZ_ASAN_BLACKLIST is a macro to tell AddressSanitizer (a compile-time + * instrumentation shipped with Clang and GCC) to not instrument the annotated + * function. Furthermore, it will prevent the compiler from inlining the + * function because inlining currently breaks the blacklisting mechanism of + * AddressSanitizer. + */ +#if defined(__has_feature) +# if __has_feature(address_sanitizer) +# define MOZ_HAVE_ASAN_BLACKLIST +# endif +#elif defined(__GNUC__) +# if defined(__SANITIZE_ADDRESS__) +# define MOZ_HAVE_ASAN_BLACKLIST +# endif +#endif + +#if defined(MOZ_HAVE_ASAN_BLACKLIST) +# define MOZ_ASAN_BLACKLIST MOZ_NEVER_INLINE __attribute__((no_sanitize_address)) +#else +# define MOZ_ASAN_BLACKLIST /* nothing */ +#endif + +/* + * MOZ_TSAN_BLACKLIST is a macro to tell ThreadSanitizer (a compile-time + * instrumentation shipped with Clang) to not instrument the annotated function. + * Furthermore, it will prevent the compiler from inlining the function because + * inlining currently breaks the blacklisting mechanism of ThreadSanitizer. + */ +#if defined(__has_feature) +# if __has_feature(thread_sanitizer) +# define MOZ_TSAN_BLACKLIST MOZ_NEVER_INLINE __attribute__((no_sanitize_thread)) +# else +# define MOZ_TSAN_BLACKLIST /* nothing */ +# endif +#else +# define MOZ_TSAN_BLACKLIST /* nothing */ +#endif + +/** + * MOZ_ALLOCATOR tells the compiler that the function it marks returns either a + * "fresh", "pointer-free" block of memory, or nullptr. "Fresh" means that the + * block is not pointed to by any other reachable pointer in the program. + * "Pointer-free" means that the block contains no pointers to any valid object + * in the program. It may be initialized with other (non-pointer) values. + * + * Placing this attribute on appropriate functions helps GCC analyze pointer + * aliasing more accurately in their callers. + * + * GCC warns if a caller ignores the value returned by a function marked with + * MOZ_ALLOCATOR: it is hard to imagine cases where dropping the value returned + * by a function that meets the criteria above would be intentional. + * + * Place this attribute after the argument list and 'this' qualifiers of a + * function definition. For example, write + * + * void *my_allocator(size_t) MOZ_ALLOCATOR; + * + * or + * + * void *my_allocator(size_t bytes) MOZ_ALLOCATOR { ... } + */ +#if defined(__GNUC__) || defined(__clang__) +# define MOZ_ALLOCATOR __attribute__ ((malloc, warn_unused_result)) +#else +# define MOZ_ALLOCATOR +#endif + +/** + * MOZ_MUST_USE tells the compiler to emit a warning if a function's + * return value is not used by the caller. + * + * Place this attribute at the very beginning of a function declaration. For + * example, write + * + * MOZ_MUST_USE int foo(); + * + * or + * + * MOZ_MUST_USE int foo() { return 42; } + */ +#if defined(__GNUC__) || defined(__clang__) +# define MOZ_MUST_USE __attribute__ ((warn_unused_result)) +#else +# define MOZ_MUST_USE +#endif + +/** + * MOZ_FALLTHROUGH is an annotation to suppress compiler warnings about switch + * cases that fall through without a break or return statement. MOZ_FALLTHROUGH + * is only needed on cases that have code. + * + * MOZ_FALLTHROUGH_ASSERT is an annotation to suppress compiler warnings about + * switch cases that MOZ_ASSERT(false) (or its alias MOZ_ASSERT_UNREACHABLE) in + * debug builds, but intentionally fall through in release builds. See comment + * in Assertions.h for more details. + * + * switch (foo) { + * case 1: // These cases have no code. No fallthrough annotations are needed. + * case 2: + * case 3: // This case has code, so a fallthrough annotation is needed! + * foo++; + * MOZ_FALLTHROUGH; + * case 4: + * return foo; + * + * default: + * // This case asserts in debug builds, falls through in release. + * MOZ_FALLTHROUGH_ASSERT("Unexpected foo value?!"); + * case 5: + * return 5; + * } + */ +#if defined(__clang__) && __cplusplus >= 201103L + /* clang's fallthrough annotations are only available starting in C++11. */ +# define MOZ_FALLTHROUGH [[clang::fallthrough]] +#elif defined(_MSC_VER) + /* + * MSVC's __fallthrough annotations are checked by /analyze (Code Analysis): + * https://msdn.microsoft.com/en-us/library/ms235402%28VS.80%29.aspx + */ +# include <sal.h> +# define MOZ_FALLTHROUGH __fallthrough +#else +# define MOZ_FALLTHROUGH /* FALLTHROUGH */ +#endif + +#ifdef __cplusplus + +/* + * The following macros are attributes that support the static analysis plugin + * included with Mozilla, and will be implemented (when such support is enabled) + * as C++11 attributes. Since such attributes are legal pretty much everywhere + * and have subtly different semantics depending on their placement, the + * following is a guide on where to place the attributes. + * + * Attributes that apply to a struct or class precede the name of the class: + * (Note that this is different from the placement of final for classes!) + * + * class MOZ_CLASS_ATTRIBUTE SomeClass {}; + * + * Attributes that apply to functions follow the parentheses and const + * qualifiers but precede final, override and the function body: + * + * void DeclaredFunction() MOZ_FUNCTION_ATTRIBUTE; + * void SomeFunction() MOZ_FUNCTION_ATTRIBUTE {} + * void PureFunction() const MOZ_FUNCTION_ATTRIBUTE = 0; + * void OverriddenFunction() MOZ_FUNCTION_ATTIRBUTE override; + * + * Attributes that apply to variables or parameters follow the variable's name: + * + * int variable MOZ_VARIABLE_ATTRIBUTE; + * + * Attributes that apply to types follow the type name: + * + * typedef int MOZ_TYPE_ATTRIBUTE MagicInt; + * int MOZ_TYPE_ATTRIBUTE someVariable; + * int* MOZ_TYPE_ATTRIBUTE magicPtrInt; + * int MOZ_TYPE_ATTRIBUTE* ptrToMagicInt; + * + * Attributes that apply to statements precede the statement: + * + * MOZ_IF_ATTRIBUTE if (x == 0) + * MOZ_DO_ATTRIBUTE do { } while (0); + * + * Attributes that apply to labels precede the label: + * + * MOZ_LABEL_ATTRIBUTE target: + * goto target; + * MOZ_CASE_ATTRIBUTE case 5: + * MOZ_DEFAULT_ATTRIBUTE default: + * + * The static analyses that are performed by the plugin are as follows: + * + * MOZ_MUST_OVERRIDE: Applies to all C++ member functions. All immediate + * subclasses must provide an exact override of this method; if a subclass + * does not override this method, the compiler will emit an error. This + * attribute is not limited to virtual methods, so if it is applied to a + * nonvirtual method and the subclass does not provide an equivalent + * definition, the compiler will emit an error. + * MOZ_STACK_CLASS: Applies to all classes. Any class with this annotation is + * expected to live on the stack, so it is a compile-time error to use it, or + * an array of such objects, as a global or static variable, or as the type of + * a new expression (unless placement new is being used). If a member of + * another class uses this class, or if another class inherits from this + * class, then it is considered to be a stack class as well, although this + * attribute need not be provided in such cases. + * MOZ_NONHEAP_CLASS: Applies to all classes. Any class with this annotation is + * expected to live on the stack or in static storage, so it is a compile-time + * error to use it, or an array of such objects, as the type of a new + * expression. If a member of another class uses this class, or if another + * class inherits from this class, then it is considered to be a non-heap class + * as well, although this attribute need not be provided in such cases. + * MOZ_HEAP_CLASS: Applies to all classes. Any class with this annotation is + * expected to live on the heap, so it is a compile-time error to use it, or + * an array of such objects, as the type of a variable declaration, or as a + * temporary object. If a member of another class uses this class, or if + * another class inherits from this class, then it is considered to be a heap + * class as well, although this attribute need not be provided in such cases. + * MOZ_NON_TEMPORARY_CLASS: Applies to all classes. Any class with this + * annotation is expected not to live in a temporary. If a member of another + * class uses this class or if another class inherits from this class, then it + * is considered to be a non-temporary class as well, although this attribute + * need not be provided in such cases. + * MOZ_RAII: Applies to all classes. Any class with this annotation is assumed + * to be a RAII guard, which is expected to live on the stack in an automatic + * allocation. It is prohibited from being allocated in a temporary, static + * storage, or on the heap. This is a combination of MOZ_STACK_CLASS and + * MOZ_NON_TEMPORARY_CLASS. + * MOZ_ONLY_USED_TO_AVOID_STATIC_CONSTRUCTORS: Applies to all classes that are + * intended to prevent introducing static initializers. This attribute + * currently makes it a compile-time error to instantiate these classes + * anywhere other than at the global scope, or as a static member of a class. + * In non-debug mode, it also prohibits non-trivial constructors and + * destructors. + * MOZ_TRIVIAL_CTOR_DTOR: Applies to all classes that must have both a trivial + * or constexpr constructor and a trivial destructor. Setting this attribute + * on a class makes it a compile-time error for that class to get a + * non-trivial constructor or destructor for any reason. + * MOZ_HEAP_ALLOCATOR: Applies to any function. This indicates that the return + * value is allocated on the heap, and will as a result check such allocations + * during MOZ_STACK_CLASS and MOZ_NONHEAP_CLASS annotation checking. + * MOZ_IMPLICIT: Applies to constructors. Implicit conversion constructors + * are disallowed by default unless they are marked as MOZ_IMPLICIT. This + * attribute must be used for constructors which intend to provide implicit + * conversions. + * MOZ_NO_ARITHMETIC_EXPR_IN_ARGUMENT: Applies to functions. Makes it a compile + * time error to pass arithmetic expressions on variables to the function. + * MOZ_OWNING_REF: Applies to declarations of pointers to reference counted + * types. This attribute tells the compiler that the raw pointer is a strong + * reference, where ownership through methods such as AddRef and Release is + * managed manually. This can make the compiler ignore these pointers when + * validating the usage of pointers otherwise. + * + * Example uses include owned pointers inside of unions, and pointers stored + * in POD types where a using a smart pointer class would make the object + * non-POD. + * MOZ_NON_OWNING_REF: Applies to declarations of pointers to reference counted + * types. This attribute tells the compiler that the raw pointer is a weak + * reference, which is ensured to be valid by a guarantee that the reference + * will be nulled before the pointer becomes invalid. This can make the compiler + * ignore these pointers when validating the usage of pointers otherwise. + * + * Examples include an mOwner pointer, which is nulled by the owning class's + * destructor, and is null-checked before dereferencing. + * MOZ_UNSAFE_REF: Applies to declarations of pointers to reference counted types. + * Occasionally there are non-owning references which are valid, but do not take + * the form of a MOZ_NON_OWNING_REF. Their safety may be dependent on the behaviour + * of API consumers. The string argument passed to this macro documents the safety + * conditions. This can make the compiler ignore these pointers when validating + * the usage of pointers elsewhere. + * + * Examples include an nsIAtom* member which is known at compile time to point to a + * static atom which is valid throughout the lifetime of the program, or an API which + * stores a pointer, but doesn't take ownership over it, instead requiring the API + * consumer to correctly null the value before it becomes invalid. + * + * Use of this annotation is discouraged when a strong reference or one of the above + * two annotations can be used instead. + * MOZ_NO_ADDREF_RELEASE_ON_RETURN: Applies to function declarations. Makes it + * a compile time error to call AddRef or Release on the return value of a + * function. This is intended to be used with operator->() of our smart + * pointer classes to ensure that the refcount of an object wrapped in a + * smart pointer is not manipulated directly. + * MOZ_MUST_USE_TYPE: Applies to type declarations. Makes it a compile time + * error to not use the return value of a function which has this type. This + * is intended to be used with types which it is an error to not use. + * MOZ_NEEDS_NO_VTABLE_TYPE: Applies to template class declarations. Makes it + * a compile time error to instantiate this template with a type parameter which + * has a VTable. + * MOZ_NON_MEMMOVABLE: Applies to class declarations for types that are not safe + * to be moved in memory using memmove(). + * MOZ_NEEDS_MEMMOVABLE_TYPE: Applies to template class declarations where the + * template arguments are required to be safe to move in memory using + * memmove(). Passing MOZ_NON_MEMMOVABLE types to these templates is a + * compile time error. + * MOZ_NEEDS_MEMMOVABLE_MEMBERS: Applies to class declarations where each member + * must be safe to move in memory using memmove(). MOZ_NON_MEMMOVABLE types + * used in members of these classes are compile time errors. + * MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS: Applies to template class + * declarations where an instance of the template should be considered, for + * static analysis purposes, to inherit any type annotations (such as + * MOZ_MUST_USE_TYPE and MOZ_STACK_CLASS) from its template arguments. + * MOZ_INIT_OUTSIDE_CTOR: Applies to class member declarations. Occasionally + * there are class members that are not initialized in the constructor, + * but logic elsewhere in the class ensures they are initialized prior to use. + * Using this attribute on a member disables the check that this member must be + * initialized in constructors via list-initialization, in the constructor body, + * or via functions called from the constructor body. + * MOZ_IS_CLASS_INIT: Applies to class method declarations. Occasionally the + * constructor doesn't initialize all of the member variables and another function + * is used to initialize the rest. This marker is used to make the static analysis + * tool aware that the marked function is part of the initialization process + * and to include the marked function in the scan mechanism that determines witch + * member variables still remain uninitialized. + * MOZ_NON_PARAM: Applies to types. Makes it compile time error to use the type + * in parameter without pointer or reference. + * MOZ_NON_AUTOABLE: Applies to class declarations. Makes it a compile time error to + * use `auto` in place of this type in variable declarations. This is intended to + * be used with types which are intended to be implicitly constructed into other + * other types before being assigned to variables. + * MOZ_REQUIRED_BASE_METHOD: Applies to virtual class method declarations. + * Sometimes derived classes override methods that need to be called by their + * overridden counterparts. This marker indicates that the marked method must + * be called by the method that it overrides. + */ +#ifdef MOZ_CLANG_PLUGIN +# define MOZ_MUST_OVERRIDE __attribute__((annotate("moz_must_override"))) +# define MOZ_STACK_CLASS __attribute__((annotate("moz_stack_class"))) +# define MOZ_NONHEAP_CLASS __attribute__((annotate("moz_nonheap_class"))) +# define MOZ_HEAP_CLASS __attribute__((annotate("moz_heap_class"))) +# define MOZ_NON_TEMPORARY_CLASS __attribute__((annotate("moz_non_temporary_class"))) +# define MOZ_TRIVIAL_CTOR_DTOR __attribute__((annotate("moz_trivial_ctor_dtor"))) +# ifdef DEBUG + /* in debug builds, these classes do have non-trivial constructors. */ +# define MOZ_ONLY_USED_TO_AVOID_STATIC_CONSTRUCTORS __attribute__((annotate("moz_global_class"))) +# else +# define MOZ_ONLY_USED_TO_AVOID_STATIC_CONSTRUCTORS __attribute__((annotate("moz_global_class"))) \ + MOZ_TRIVIAL_CTOR_DTOR +# endif +# define MOZ_IMPLICIT __attribute__((annotate("moz_implicit"))) +# define MOZ_NO_ARITHMETIC_EXPR_IN_ARGUMENT __attribute__((annotate("moz_no_arith_expr_in_arg"))) +# define MOZ_OWNING_REF __attribute__((annotate("moz_strong_ref"))) +# define MOZ_NON_OWNING_REF __attribute__((annotate("moz_weak_ref"))) +# define MOZ_UNSAFE_REF(reason) __attribute__((annotate("moz_weak_ref"))) +# define MOZ_NO_ADDREF_RELEASE_ON_RETURN __attribute__((annotate("moz_no_addref_release_on_return"))) +# define MOZ_MUST_USE_TYPE __attribute__((annotate("moz_must_use_type"))) +# define MOZ_NEEDS_NO_VTABLE_TYPE __attribute__((annotate("moz_needs_no_vtable_type"))) +# define MOZ_NON_MEMMOVABLE __attribute__((annotate("moz_non_memmovable"))) +# define MOZ_NEEDS_MEMMOVABLE_TYPE __attribute__((annotate("moz_needs_memmovable_type"))) +# define MOZ_NEEDS_MEMMOVABLE_MEMBERS __attribute__((annotate("moz_needs_memmovable_members"))) +# define MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS \ + __attribute__((annotate("moz_inherit_type_annotations_from_template_args"))) +# define MOZ_NON_AUTOABLE __attribute__((annotate("moz_non_autoable"))) +# define MOZ_INIT_OUTSIDE_CTOR \ + __attribute__((annotate("moz_ignore_ctor_initialization"))) +# define MOZ_IS_CLASS_INIT \ + __attribute__((annotate("moz_is_class_init"))) +# define MOZ_NON_PARAM \ + __attribute__((annotate("moz_non_param"))) +# define MOZ_REQUIRED_BASE_METHOD \ + __attribute__((annotate("moz_required_base_method"))) +/* + * It turns out that clang doesn't like void func() __attribute__ {} without a + * warning, so use pragmas to disable the warning. This code won't work on GCC + * anyways, so the warning is safe to ignore. + */ +# define MOZ_HEAP_ALLOCATOR \ + _Pragma("clang diagnostic push") \ + _Pragma("clang diagnostic ignored \"-Wgcc-compat\"") \ + __attribute__((annotate("moz_heap_allocator"))) \ + _Pragma("clang diagnostic pop") +#else +# define MOZ_MUST_OVERRIDE /* nothing */ +# define MOZ_STACK_CLASS /* nothing */ +# define MOZ_NONHEAP_CLASS /* nothing */ +# define MOZ_HEAP_CLASS /* nothing */ +# define MOZ_NON_TEMPORARY_CLASS /* nothing */ +# define MOZ_TRIVIAL_CTOR_DTOR /* nothing */ +# define MOZ_ONLY_USED_TO_AVOID_STATIC_CONSTRUCTORS /* nothing */ +# define MOZ_IMPLICIT /* nothing */ +# define MOZ_NO_ARITHMETIC_EXPR_IN_ARGUMENT /* nothing */ +# define MOZ_HEAP_ALLOCATOR /* nothing */ +# define MOZ_OWNING_REF /* nothing */ +# define MOZ_NON_OWNING_REF /* nothing */ +# define MOZ_UNSAFE_REF(reason) /* nothing */ +# define MOZ_NO_ADDREF_RELEASE_ON_RETURN /* nothing */ +# define MOZ_MUST_USE_TYPE /* nothing */ +# define MOZ_NEEDS_NO_VTABLE_TYPE /* nothing */ +# define MOZ_NON_MEMMOVABLE /* nothing */ +# define MOZ_NEEDS_MEMMOVABLE_TYPE /* nothing */ +# define MOZ_NEEDS_MEMMOVABLE_MEMBERS /* nothing */ +# define MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS /* nothing */ +# define MOZ_INIT_OUTSIDE_CTOR /* nothing */ +# define MOZ_IS_CLASS_INIT /* nothing */ +# define MOZ_NON_PARAM /* nothing */ +# define MOZ_NON_AUTOABLE /* nothing */ +# define MOZ_REQUIRED_BASE_METHOD /* nothing */ +#endif /* MOZ_CLANG_PLUGIN */ + +#define MOZ_RAII MOZ_NON_TEMPORARY_CLASS MOZ_STACK_CLASS + +/* + * MOZ_HAVE_REF_QUALIFIERS is defined for compilers that support C++11's rvalue + * qualifier, "&&". + */ +#if defined(_MSC_VER) && _MSC_VER >= 1900 +# define MOZ_HAVE_REF_QUALIFIERS +#elif defined(__clang__) +// All supported Clang versions +# define MOZ_HAVE_REF_QUALIFIERS +#elif defined(__GNUC__) +# include "mozilla/Compiler.h" +# if MOZ_GCC_VERSION_AT_LEAST(4, 8, 1) +# define MOZ_HAVE_REF_QUALIFIERS +# endif +#endif + +#endif /* __cplusplus */ + +/** + * Printf style formats. MOZ_FORMAT_PRINTF can be used to annotate a + * function or method that is "printf-like"; this will let (some) + * compilers check that the arguments match the template string. + * + * This macro takes two arguments. The first argument is the argument + * number of the template string. The second argument is the argument + * number of the '...' argument holding the arguments. + * + * Argument numbers start at 1. Note that the implicit "this" + * argument of a non-static member function counts as an argument. + * + * So, for a simple case like: + * void print_something (int whatever, const char *fmt, ...); + * The corresponding annotation would be + * MOZ_FORMAT_PRINTF(2, 3) + * However, if "print_something" were a non-static member function, + * then the annotation would be: + * MOZ_FORMAT_PRINTF(3, 4) + * + * Note that the checking is limited to standards-conforming + * printf-likes, and in particular this should not be used for + * PR_snprintf and friends, which are "printf-like" but which assign + * different meanings to the various formats. + */ +#ifdef __GNUC__ +#define MOZ_FORMAT_PRINTF(stringIndex, firstToCheck) \ + __attribute__ ((format (printf, stringIndex, firstToCheck))) +#else +#define MOZ_FORMAT_PRINTF(stringIndex, firstToCheck) +#endif + +#endif /* mozilla_Attributes_h */ diff --git a/mfbt/BinarySearch.h b/mfbt/BinarySearch.h new file mode 100644 index 000000000..1bbe05669 --- /dev/null +++ b/mfbt/BinarySearch.h @@ -0,0 +1,139 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef mozilla_BinarySearch_h +#define mozilla_BinarySearch_h + +#include "mozilla/Assertions.h" + +#include <stddef.h> + +namespace mozilla { + +/* + * The BinarySearch() algorithm searches the given container |aContainer| over + * the sorted index range [aBegin, aEnd) for an index |i| where + * |aContainer[i] == aTarget|. + * If such an index |i| is found, BinarySearch returns |true| and the index is + * returned via the outparam |aMatchOrInsertionPoint|. If no index is found, + * BinarySearch returns |false| and the outparam returns the first index in + * [aBegin, aEnd] where |aTarget| can be inserted to maintain sorted order. + * + * Example: + * + * Vector<int> sortedInts = ... + * + * size_t match; + * if (BinarySearch(sortedInts, 0, sortedInts.length(), 13, &match)) { + * printf("found 13 at %lu\n", match); + * } + * + * The BinarySearchIf() version behaves similarly, but takes |aComparator|, a + * functor to compare the values with, instead of a value to find. + * That functor should take one argument - the value to compare - and return an + * |int| with the comparison result: + * + * * 0, if the argument is equal to, + * * less than 0, if the argument is greater than, + * * greater than 0, if the argument is less than + * + * the value. + * + * Example: + * + * struct Comparator { + * int operator()(int aVal) const { + * if (mTarget < aVal) { return -1; } + * if (mTarget > aVal) { return 1; } + * return 0; + * } + * explicit Comparator(int aTarget) : mTarget(aTarget) {} + * const int mTarget; + * }; + * + * Vector<int> sortedInts = ... + * + * size_t match; + * if (BinarySearchIf(sortedInts, 0, sortedInts.length(), Comparator(13), &match)) { + * printf("found 13 at %lu\n", match); + * } + * + */ + +template<typename Container, typename Comparator> +bool +BinarySearchIf(const Container& aContainer, size_t aBegin, size_t aEnd, + const Comparator& aCompare, size_t* aMatchOrInsertionPoint) +{ + MOZ_ASSERT(aBegin <= aEnd); + + size_t low = aBegin; + size_t high = aEnd; + while (high != low) { + size_t middle = low + (high - low) / 2; + + // Allow any intermediate type so long as it provides a suitable ordering + // relation. + const int result = aCompare(aContainer[middle]); + + if (result == 0) { + *aMatchOrInsertionPoint = middle; + return true; + } + + if (result < 0) { + high = middle; + } else { + low = middle + 1; + } + } + + *aMatchOrInsertionPoint = low; + return false; +} + +namespace detail { + +template<class T> +class BinarySearchDefaultComparator +{ +public: + explicit BinarySearchDefaultComparator(const T& aTarget) + : mTarget(aTarget) + {} + + template <class U> + int operator()(const U& aVal) const { + if (mTarget == aVal) { + return 0; + } + + if (mTarget < aVal) { + return -1; + } + + return 1; + } + +private: + const T& mTarget; +}; + +} // namespace detail + +template <typename Container, typename T> +bool +BinarySearch(const Container& aContainer, size_t aBegin, size_t aEnd, + T aTarget, size_t* aMatchOrInsertionPoint) +{ + return BinarySearchIf(aContainer, aBegin, aEnd, + detail::BinarySearchDefaultComparator<T>(aTarget), + aMatchOrInsertionPoint); +} + +} // namespace mozilla + +#endif // mozilla_BinarySearch_h diff --git a/mfbt/BloomFilter.h b/mfbt/BloomFilter.h new file mode 100644 index 000000000..6757e4118 --- /dev/null +++ b/mfbt/BloomFilter.h @@ -0,0 +1,256 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* + * A counting Bloom filter implementation. This allows consumers to + * do fast probabilistic "is item X in set Y?" testing which will + * never answer "no" when the correct answer is "yes" (but might + * incorrectly answer "yes" when the correct answer is "no"). + */ + +#ifndef mozilla_BloomFilter_h +#define mozilla_BloomFilter_h + +#include "mozilla/Assertions.h" +#include "mozilla/Likely.h" + +#include <stdint.h> +#include <string.h> + +namespace mozilla { + +/* + * This class implements a counting Bloom filter as described at + * <http://en.wikipedia.org/wiki/Bloom_filter#Counting_filters>, with + * 8-bit counters. This allows quick probabilistic answers to the + * question "is object X in set Y?" where the contents of Y might not + * be time-invariant. The probabilistic nature of the test means that + * sometimes the answer will be "yes" when it should be "no". If the + * answer is "no", then X is guaranteed not to be in Y. + * + * The filter is parametrized on KeySize, which is the size of the key + * generated by each of hash functions used by the filter, in bits, + * and the type of object T being added and removed. T must implement + * a |uint32_t hash() const| method which returns a uint32_t hash key + * that will be used to generate the two separate hash functions for + * the Bloom filter. This hash key MUST be well-distributed for good + * results! KeySize is not allowed to be larger than 16. + * + * The filter uses exactly 2**KeySize bytes of memory. From now on we + * will refer to the memory used by the filter as M. + * + * The expected rate of incorrect "yes" answers depends on M and on + * the number N of objects in set Y. As long as N is small compared + * to M, the rate of such answers is expected to be approximately + * 4*(N/M)**2 for this filter. In practice, if Y has a few hundred + * elements then using a KeySize of 12 gives a reasonably low + * incorrect answer rate. A KeySize of 12 has the additional benefit + * of using exactly one page for the filter in typical hardware + * configurations. + */ + +template<unsigned KeySize, class T> +class BloomFilter +{ + /* + * A counting Bloom filter with 8-bit counters. For now we assume + * that having two hash functions is enough, but we may revisit that + * decision later. + * + * The filter uses an array with 2**KeySize entries. + * + * Assuming a well-distributed hash function, a Bloom filter with + * array size M containing N elements and + * using k hash function has expected false positive rate exactly + * + * $ (1 - (1 - 1/M)^{kN})^k $ + * + * because each array slot has a + * + * $ (1 - 1/M)^{kN} $ + * + * chance of being 0, and the expected false positive rate is the + * probability that all of the k hash functions will hit a nonzero + * slot. + * + * For reasonable assumptions (M large, kN large, which should both + * hold if we're worried about false positives) about M and kN this + * becomes approximately + * + * $$ (1 - \exp(-kN/M))^k $$ + * + * For our special case of k == 2, that's $(1 - \exp(-2N/M))^2$, + * or in other words + * + * $$ N/M = -0.5 * \ln(1 - \sqrt(r)) $$ + * + * where r is the false positive rate. This can be used to compute + * the desired KeySize for a given load N and false positive rate r. + * + * If N/M is assumed small, then the false positive rate can + * further be approximated as 4*N^2/M^2. So increasing KeySize by + * 1, which doubles M, reduces the false positive rate by about a + * factor of 4, and a false positive rate of 1% corresponds to + * about M/N == 20. + * + * What this means in practice is that for a few hundred keys using a + * KeySize of 12 gives false positive rates on the order of 0.25-4%. + * + * Similarly, using a KeySize of 10 would lead to a 4% false + * positive rate for N == 100 and to quite bad false positive + * rates for larger N. + */ +public: + BloomFilter() + { + static_assert(KeySize <= kKeyShift, "KeySize too big"); + + // Should we have a custom operator new using calloc instead and + // require that we're allocated via the operator? + clear(); + } + + /* + * Clear the filter. This should be done before reusing it, because + * just removing all items doesn't clear counters that hit the upper + * bound. + */ + void clear(); + + /* + * Add an item to the filter. + */ + void add(const T* aValue); + + /* + * Remove an item from the filter. + */ + void remove(const T* aValue); + + /* + * Check whether the filter might contain an item. This can + * sometimes return true even if the item is not in the filter, + * but will never return false for items that are actually in the + * filter. + */ + bool mightContain(const T* aValue) const; + + /* + * Methods for add/remove/contain when we already have a hash computed + */ + void add(uint32_t aHash); + void remove(uint32_t aHash); + bool mightContain(uint32_t aHash) const; + +private: + static const size_t kArraySize = (1 << KeySize); + static const uint32_t kKeyMask = (1 << KeySize) - 1; + static const uint32_t kKeyShift = 16; + + static uint32_t hash1(uint32_t aHash) + { + return aHash & kKeyMask; + } + static uint32_t hash2(uint32_t aHash) + { + return (aHash >> kKeyShift) & kKeyMask; + } + + uint8_t& firstSlot(uint32_t aHash) + { + return mCounters[hash1(aHash)]; + } + uint8_t& secondSlot(uint32_t aHash) + { + return mCounters[hash2(aHash)]; + } + + const uint8_t& firstSlot(uint32_t aHash) const + { + return mCounters[hash1(aHash)]; + } + const uint8_t& secondSlot(uint32_t aHash) const + { + return mCounters[hash2(aHash)]; + } + + static bool full(const uint8_t& aSlot) { return aSlot == UINT8_MAX; } + + uint8_t mCounters[kArraySize]; +}; + +template<unsigned KeySize, class T> +inline void +BloomFilter<KeySize, T>::clear() +{ + memset(mCounters, 0, kArraySize); +} + +template<unsigned KeySize, class T> +inline void +BloomFilter<KeySize, T>::add(uint32_t aHash) +{ + uint8_t& slot1 = firstSlot(aHash); + if (MOZ_LIKELY(!full(slot1))) { + ++slot1; + } + uint8_t& slot2 = secondSlot(aHash); + if (MOZ_LIKELY(!full(slot2))) { + ++slot2; + } +} + +template<unsigned KeySize, class T> +MOZ_ALWAYS_INLINE void +BloomFilter<KeySize, T>::add(const T* aValue) +{ + uint32_t hash = aValue->hash(); + return add(hash); +} + +template<unsigned KeySize, class T> +inline void +BloomFilter<KeySize, T>::remove(uint32_t aHash) +{ + // If the slots are full, we don't know whether we bumped them to be + // there when we added or not, so just leave them full. + uint8_t& slot1 = firstSlot(aHash); + if (MOZ_LIKELY(!full(slot1))) { + --slot1; + } + uint8_t& slot2 = secondSlot(aHash); + if (MOZ_LIKELY(!full(slot2))) { + --slot2; + } +} + +template<unsigned KeySize, class T> +MOZ_ALWAYS_INLINE void +BloomFilter<KeySize, T>::remove(const T* aValue) +{ + uint32_t hash = aValue->hash(); + remove(hash); +} + +template<unsigned KeySize, class T> +MOZ_ALWAYS_INLINE bool +BloomFilter<KeySize, T>::mightContain(uint32_t aHash) const +{ + // Check that all the slots for this hash contain something + return firstSlot(aHash) && secondSlot(aHash); +} + +template<unsigned KeySize, class T> +MOZ_ALWAYS_INLINE bool +BloomFilter<KeySize, T>::mightContain(const T* aValue) const +{ + uint32_t hash = aValue->hash(); + return mightContain(hash); +} + +} // namespace mozilla + +#endif /* mozilla_BloomFilter_h */ diff --git a/mfbt/BufferList.h b/mfbt/BufferList.h new file mode 100644 index 000000000..26b335957 --- /dev/null +++ b/mfbt/BufferList.h @@ -0,0 +1,520 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef mozilla_BufferList_h +#define mozilla_BufferList_h + +#include <algorithm> +#include "mozilla/AllocPolicy.h" +#include "mozilla/Move.h" +#include "mozilla/ScopeExit.h" +#include "mozilla/Types.h" +#include "mozilla/TypeTraits.h" +#include "mozilla/Vector.h" +#include <string.h> + +// Undo potential #include <windows.h> damage to be able to use std::min. +#undef min + +// BufferList represents a sequence of buffers of data. A BufferList can choose +// to own its buffers or not. The class handles writing to the buffers, +// iterating over them, and reading data out. Unlike SegmentedVector, the +// buffers may be of unequal size. Like SegmentedVector, BufferList is a nice +// way to avoid large contiguous allocations (which can trigger OOMs). + +namespace mozilla { + +template<typename AllocPolicy> +class BufferList : private AllocPolicy +{ + // Each buffer in a BufferList has a size and a capacity. The first mSize + // bytes are initialized and the remaining |mCapacity - mSize| bytes are free. + struct Segment + { + char* mData; + size_t mSize; + size_t mCapacity; + + Segment(char* aData, size_t aSize, size_t aCapacity) + : mData(aData), + mSize(aSize), + mCapacity(aCapacity) + { + } + + Segment(const Segment&) = delete; + Segment& operator=(const Segment&) = delete; + + Segment(Segment&&) = default; + Segment& operator=(Segment&&) = default; + + char* Start() const { return mData; } + char* End() const { return mData + mSize; } + }; + + template<typename OtherAllocPolicy> + friend class BufferList; + + public: + // For the convenience of callers, all segments are required to be a multiple + // of 8 bytes in capacity. Also, every buffer except the last one is required + // to be full (i.e., size == capacity). Therefore, a byte at offset N within + // the BufferList and stored in memory at an address A will satisfy + // (N % Align == A % Align) if Align == 2, 4, or 8. + static const size_t kSegmentAlignment = 8; + + // Allocate a BufferList. The BufferList will free all its buffers when it is + // destroyed. An initial buffer of size aInitialSize and capacity + // aInitialCapacity is allocated automatically. This data will be contiguous + // an can be accessed via |Start()|. Subsequent buffers will be allocated with + // capacity aStandardCapacity. + BufferList(size_t aInitialSize, + size_t aInitialCapacity, + size_t aStandardCapacity, + AllocPolicy aAP = AllocPolicy()) + : AllocPolicy(aAP), + mOwning(true), + mSegments(aAP), + mSize(0), + mStandardCapacity(aStandardCapacity) + { + MOZ_ASSERT(aInitialCapacity % kSegmentAlignment == 0); + MOZ_ASSERT(aStandardCapacity % kSegmentAlignment == 0); + + if (aInitialCapacity) { + AllocateSegment(aInitialSize, aInitialCapacity); + } + } + + BufferList(const BufferList& aOther) = delete; + + BufferList(BufferList&& aOther) + : mOwning(aOther.mOwning), + mSegments(Move(aOther.mSegments)), + mSize(aOther.mSize), + mStandardCapacity(aOther.mStandardCapacity) + { + aOther.mSegments.clear(); + aOther.mSize = 0; + } + + BufferList& operator=(const BufferList& aOther) = delete; + + BufferList& operator=(BufferList&& aOther) + { + Clear(); + + mOwning = aOther.mOwning; + mSegments = Move(aOther.mSegments); + mSize = aOther.mSize; + aOther.mSegments.clear(); + aOther.mSize = 0; + return *this; + } + + ~BufferList() { Clear(); } + + // Returns the sum of the sizes of all the buffers. + size_t Size() const { return mSize; } + + void Clear() + { + if (mOwning) { + for (Segment& segment : mSegments) { + this->free_(segment.mData); + } + } + mSegments.clear(); + + mSize = 0; + } + + // Iterates over bytes in the segments. You can advance it by as many bytes as + // you choose. + class IterImpl + { + // Invariants: + // (0) mSegment <= bufferList.mSegments.size() + // (1) mData <= mDataEnd + // (2) If mSegment is not the last segment, mData < mDataEnd + uintptr_t mSegment; + char* mData; + char* mDataEnd; + + friend class BufferList; + + public: + explicit IterImpl(const BufferList& aBuffers) + : mSegment(0), + mData(nullptr), + mDataEnd(nullptr) + { + if (!aBuffers.mSegments.empty()) { + mData = aBuffers.mSegments[0].Start(); + mDataEnd = aBuffers.mSegments[0].End(); + } + } + + // Returns a pointer to the raw data. It is valid to access up to + // RemainingInSegment bytes of this buffer. + char* Data() const + { + MOZ_RELEASE_ASSERT(!Done()); + return mData; + } + + // Returns true if the memory in the range [Data(), Data() + aBytes) is all + // part of one contiguous buffer. + bool HasRoomFor(size_t aBytes) const + { + MOZ_RELEASE_ASSERT(mData <= mDataEnd); + return size_t(mDataEnd - mData) >= aBytes; + } + + // Returns the maximum value aBytes for which HasRoomFor(aBytes) will be + // true. + size_t RemainingInSegment() const + { + MOZ_RELEASE_ASSERT(mData <= mDataEnd); + return mDataEnd - mData; + } + + // Advances the iterator by aBytes bytes. aBytes must be less than + // RemainingInSegment(). If advancing by aBytes takes the iterator to the + // end of a buffer, it will be moved to the beginning of the next buffer + // unless it is the last buffer. + void Advance(const BufferList& aBuffers, size_t aBytes) + { + const Segment& segment = aBuffers.mSegments[mSegment]; + MOZ_RELEASE_ASSERT(segment.Start() <= mData); + MOZ_RELEASE_ASSERT(mData <= mDataEnd); + MOZ_RELEASE_ASSERT(mDataEnd == segment.End()); + + MOZ_RELEASE_ASSERT(HasRoomFor(aBytes)); + mData += aBytes; + + if (mData == mDataEnd && mSegment + 1 < aBuffers.mSegments.length()) { + mSegment++; + const Segment& nextSegment = aBuffers.mSegments[mSegment]; + mData = nextSegment.Start(); + mDataEnd = nextSegment.End(); + MOZ_RELEASE_ASSERT(mData < mDataEnd); + } + } + + // Advance the iterator by aBytes, possibly crossing segments. This function + // returns false if it runs out of buffers to advance through. Otherwise it + // returns true. + bool AdvanceAcrossSegments(const BufferList& aBuffers, size_t aBytes) + { + size_t bytes = aBytes; + while (bytes) { + size_t toAdvance = std::min(bytes, RemainingInSegment()); + if (!toAdvance) { + return false; + } + Advance(aBuffers, toAdvance); + bytes -= toAdvance; + } + return true; + } + + // Returns true when the iterator reaches the end of the BufferList. + bool Done() const + { + return mData == mDataEnd; + } + + private: + + // Count the bytes we would need to advance in order to reach aTarget. + size_t BytesUntil(const BufferList& aBuffers, const IterImpl& aTarget) const { + size_t offset = 0; + + MOZ_ASSERT(aTarget.IsIn(aBuffers)); + + char* data = mData; + for (uintptr_t segment = mSegment; segment < aTarget.mSegment; segment++) { + offset += aBuffers.mSegments[segment].End() - data; + data = aBuffers.mSegments[segment].mData; + } + + MOZ_RELEASE_ASSERT(IsIn(aBuffers)); + MOZ_RELEASE_ASSERT(aTarget.mData >= data); + + offset += aTarget.mData - data; + return offset; + } + + bool IsIn(const BufferList& aBuffers) const { + return mSegment < aBuffers.mSegments.length() && + mData >= aBuffers.mSegments[mSegment].mData && + mData < aBuffers.mSegments[mSegment].End(); + } + }; + + // Special convenience method that returns Iter().Data(). + char* Start() { return mSegments[0].mData; } + const char* Start() const { return mSegments[0].mData; } + + IterImpl Iter() const { return IterImpl(*this); } + + // Copies aSize bytes from aData into the BufferList. The storage for these + // bytes may be split across multiple buffers. Size() is increased by aSize. + inline bool WriteBytes(const char* aData, size_t aSize); + + // Copies possibly non-contiguous byte range starting at aIter into + // aData. aIter is advanced by aSize bytes. Returns false if it runs out of + // data before aSize. + inline bool ReadBytes(IterImpl& aIter, char* aData, size_t aSize) const; + + // Return a new BufferList that shares storage with this BufferList. The new + // BufferList is read-only. It allows iteration over aSize bytes starting at + // aIter. Borrow can fail, in which case *aSuccess will be false upon + // return. The borrowed BufferList can use a different AllocPolicy than the + // original one. However, it is not responsible for freeing buffers, so the + // AllocPolicy is only used for the buffer vector. + template<typename BorrowingAllocPolicy> + BufferList<BorrowingAllocPolicy> Borrow(IterImpl& aIter, size_t aSize, bool* aSuccess, + BorrowingAllocPolicy aAP = BorrowingAllocPolicy()) const; + + // Return a new BufferList and move storage from this BufferList to it. The + // new BufferList owns the buffers. Move can fail, in which case *aSuccess + // will be false upon return. The new BufferList can use a different + // AllocPolicy than the original one. The new OtherAllocPolicy is responsible + // for freeing buffers, so the OtherAllocPolicy must use freeing method + // compatible to the original one. + template<typename OtherAllocPolicy> + BufferList<OtherAllocPolicy> MoveFallible(bool* aSuccess, OtherAllocPolicy aAP = OtherAllocPolicy()); + + // Return a new BufferList that adopts the byte range starting at Iter so that + // range [aIter, aIter + aSize) is transplanted to the returned BufferList. + // Contents of the buffer before aIter + aSize is left undefined. + // Extract can fail, in which case *aSuccess will be false upon return. The + // moved buffers are erased from the original BufferList. In case of extract + // fails, the original BufferList is intact. All other iterators except aIter + // are invalidated. + // This method requires aIter and aSize to be 8-byte aligned. + BufferList Extract(IterImpl& aIter, size_t aSize, bool* aSuccess); + + // Return the number of bytes from 'start' to 'end', two iterators within + // this BufferList. + size_t RangeLength(const IterImpl& start, const IterImpl& end) const { + MOZ_ASSERT(start.IsIn(*this) && end.IsIn(*this)); + return start.BytesUntil(*this, end); + } + +private: + explicit BufferList(AllocPolicy aAP) + : AllocPolicy(aAP), + mOwning(false), + mSize(0), + mStandardCapacity(0) + { + } + + void* AllocateSegment(size_t aSize, size_t aCapacity) + { + MOZ_RELEASE_ASSERT(mOwning); + + char* data = this->template pod_malloc<char>(aCapacity); + if (!data) { + return nullptr; + } + if (!mSegments.append(Segment(data, aSize, aCapacity))) { + this->free_(data); + return nullptr; + } + mSize += aSize; + return data; + } + + bool mOwning; + Vector<Segment, 1, AllocPolicy> mSegments; + size_t mSize; + size_t mStandardCapacity; +}; + +template<typename AllocPolicy> +bool +BufferList<AllocPolicy>::WriteBytes(const char* aData, size_t aSize) +{ + MOZ_RELEASE_ASSERT(mOwning); + MOZ_RELEASE_ASSERT(mStandardCapacity); + + size_t copied = 0; + size_t remaining = aSize; + + if (!mSegments.empty()) { + Segment& lastSegment = mSegments.back(); + + size_t toCopy = std::min(aSize, lastSegment.mCapacity - lastSegment.mSize); + memcpy(lastSegment.mData + lastSegment.mSize, aData, toCopy); + lastSegment.mSize += toCopy; + mSize += toCopy; + + copied += toCopy; + remaining -= toCopy; + } + + while (remaining) { + size_t toCopy = std::min(remaining, mStandardCapacity); + + void* data = AllocateSegment(toCopy, mStandardCapacity); + if (!data) { + return false; + } + memcpy(data, aData + copied, toCopy); + + copied += toCopy; + remaining -= toCopy; + } + + return true; +} + +template<typename AllocPolicy> +bool +BufferList<AllocPolicy>::ReadBytes(IterImpl& aIter, char* aData, size_t aSize) const +{ + size_t copied = 0; + size_t remaining = aSize; + while (remaining) { + size_t toCopy = std::min(aIter.RemainingInSegment(), remaining); + if (!toCopy) { + // We've run out of data in the last segment. + return false; + } + memcpy(aData + copied, aIter.Data(), toCopy); + copied += toCopy; + remaining -= toCopy; + + aIter.Advance(*this, toCopy); + } + + return true; +} + +template<typename AllocPolicy> template<typename BorrowingAllocPolicy> +BufferList<BorrowingAllocPolicy> +BufferList<AllocPolicy>::Borrow(IterImpl& aIter, size_t aSize, bool* aSuccess, + BorrowingAllocPolicy aAP) const +{ + BufferList<BorrowingAllocPolicy> result(aAP); + + size_t size = aSize; + while (size) { + size_t toAdvance = std::min(size, aIter.RemainingInSegment()); + + if (!toAdvance || !result.mSegments.append(typename BufferList<BorrowingAllocPolicy>::Segment(aIter.mData, toAdvance, toAdvance))) { + *aSuccess = false; + return result; + } + aIter.Advance(*this, toAdvance); + size -= toAdvance; + } + + result.mSize = aSize; + *aSuccess = true; + return result; +} + +template<typename AllocPolicy> template<typename OtherAllocPolicy> +BufferList<OtherAllocPolicy> +BufferList<AllocPolicy>::MoveFallible(bool* aSuccess, OtherAllocPolicy aAP) +{ + BufferList<OtherAllocPolicy> result(0, 0, mStandardCapacity, aAP); + + IterImpl iter = Iter(); + while (!iter.Done()) { + size_t toAdvance = iter.RemainingInSegment(); + + if (!toAdvance || !result.mSegments.append(typename BufferList<OtherAllocPolicy>::Segment(iter.mData, toAdvance, toAdvance))) { + *aSuccess = false; + result.mSegments.clear(); + return result; + } + iter.Advance(*this, toAdvance); + } + + result.mSize = mSize; + mSegments.clear(); + mSize = 0; + *aSuccess = true; + return result; +} + +template<typename AllocPolicy> +BufferList<AllocPolicy> +BufferList<AllocPolicy>::Extract(IterImpl& aIter, size_t aSize, bool* aSuccess) +{ + MOZ_RELEASE_ASSERT(aSize); + MOZ_RELEASE_ASSERT(mOwning); + MOZ_ASSERT(aSize % kSegmentAlignment == 0); + MOZ_ASSERT(intptr_t(aIter.mData) % kSegmentAlignment == 0); + + IterImpl iter = aIter; + size_t size = aSize; + size_t toCopy = std::min(size, aIter.RemainingInSegment()); + MOZ_ASSERT(toCopy % kSegmentAlignment == 0); + + BufferList result(0, toCopy, mStandardCapacity); + BufferList error(0, 0, mStandardCapacity); + + // Copy the head + if (!result.WriteBytes(aIter.mData, toCopy)) { + *aSuccess = false; + return error; + } + iter.Advance(*this, toCopy); + size -= toCopy; + + // Move segments to result + auto resultGuard = MakeScopeExit([&] { + *aSuccess = false; + result.mSegments.erase(result.mSegments.begin()+1, result.mSegments.end()); + }); + + size_t movedSize = 0; + uintptr_t toRemoveStart = iter.mSegment; + uintptr_t toRemoveEnd = iter.mSegment; + while (!iter.Done() && + !iter.HasRoomFor(size)) { + if (!result.mSegments.append(Segment(mSegments[iter.mSegment].mData, + mSegments[iter.mSegment].mSize, + mSegments[iter.mSegment].mCapacity))) { + return error; + } + movedSize += iter.RemainingInSegment(); + size -= iter.RemainingInSegment(); + toRemoveEnd++; + iter.Advance(*this, iter.RemainingInSegment()); + } + + if (size) { + if (!iter.HasRoomFor(size) || + !result.WriteBytes(iter.Data(), size)) { + return error; + } + iter.Advance(*this, size); + } + + mSegments.erase(mSegments.begin() + toRemoveStart, mSegments.begin() + toRemoveEnd); + mSize -= movedSize; + aIter.mSegment = iter.mSegment - (toRemoveEnd - toRemoveStart); + aIter.mData = iter.mData; + aIter.mDataEnd = iter.mDataEnd; + MOZ_ASSERT(aIter.mDataEnd == mSegments[aIter.mSegment].End()); + result.mSize = aSize; + + resultGuard.release(); + *aSuccess = true; + return result; +} + +} // namespace mozilla + +#endif /* mozilla_BufferList_h */ diff --git a/mfbt/Casting.h b/mfbt/Casting.h new file mode 100644 index 000000000..a7d0fb50d --- /dev/null +++ b/mfbt/Casting.h @@ -0,0 +1,243 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Cast operations to supplement the built-in casting operations. */ + +#ifndef mozilla_Casting_h +#define mozilla_Casting_h + +#include "mozilla/Assertions.h" +#include "mozilla/TypeTraits.h" + +#include <limits.h> + +namespace mozilla { + +/** + * Sets the outparam value of type |To| with the same underlying bit pattern of + * |aFrom|. + * + * |To| and |From| must be types of the same size; be careful of cross-platform + * size differences, or this might fail to compile on some but not all + * platforms. + * + * There is also a variant that returns the value directly. In most cases, the + * two variants should be identical. However, in the specific case of x86 + * chips, the behavior differs: returning floating-point values directly is done + * through the x87 stack, and x87 loads and stores turn signaling NaNs into + * quiet NaNs... silently. Returning floating-point values via outparam, + * however, is done entirely within the SSE registers when SSE2 floating-point + * is enabled in the compiler, which has semantics-preserving behavior you would + * expect. + * + * If preserving the distinction between signaling NaNs and quiet NaNs is + * important to you, you should use the outparam version. In all other cases, + * you should use the direct return version. + */ +template<typename To, typename From> +inline void +BitwiseCast(const From aFrom, To* aResult) +{ + static_assert(sizeof(From) == sizeof(To), + "To and From must have the same size"); + union + { + From mFrom; + To mTo; + } u; + u.mFrom = aFrom; + *aResult = u.mTo; +} + +template<typename To, typename From> +inline To +BitwiseCast(const From aFrom) +{ + To temp; + BitwiseCast<To, From>(aFrom, &temp); + return temp; +} + +namespace detail { + +enum ToSignedness { ToIsSigned, ToIsUnsigned }; +enum FromSignedness { FromIsSigned, FromIsUnsigned }; + +template<typename From, + typename To, + FromSignedness = IsSigned<From>::value ? FromIsSigned : FromIsUnsigned, + ToSignedness = IsSigned<To>::value ? ToIsSigned : ToIsUnsigned> +struct BoundsCheckImpl; + +// Implicit conversions on operands to binary operations make this all a bit +// hard to verify. Attempt to ease the pain below by *only* comparing values +// that are obviously the same type (and will undergo no further conversions), +// even when it's not strictly necessary, for explicitness. + +enum UUComparison { FromIsBigger, FromIsNotBigger }; + +// Unsigned-to-unsigned range check + +template<typename From, typename To, + UUComparison = (sizeof(From) > sizeof(To)) + ? FromIsBigger + : FromIsNotBigger> +struct UnsignedUnsignedCheck; + +template<typename From, typename To> +struct UnsignedUnsignedCheck<From, To, FromIsBigger> +{ +public: + static bool checkBounds(const From aFrom) + { + return aFrom <= From(To(-1)); + } +}; + +template<typename From, typename To> +struct UnsignedUnsignedCheck<From, To, FromIsNotBigger> +{ +public: + static bool checkBounds(const From aFrom) + { + return true; + } +}; + +template<typename From, typename To> +struct BoundsCheckImpl<From, To, FromIsUnsigned, ToIsUnsigned> +{ +public: + static bool checkBounds(const From aFrom) + { + return UnsignedUnsignedCheck<From, To>::checkBounds(aFrom); + } +}; + +// Signed-to-unsigned range check + +template<typename From, typename To> +struct BoundsCheckImpl<From, To, FromIsSigned, ToIsUnsigned> +{ +public: + static bool checkBounds(const From aFrom) + { + if (aFrom < 0) { + return false; + } + if (sizeof(To) >= sizeof(From)) { + return true; + } + return aFrom <= From(To(-1)); + } +}; + +// Unsigned-to-signed range check + +enum USComparison { FromIsSmaller, FromIsNotSmaller }; + +template<typename From, typename To, + USComparison = (sizeof(From) < sizeof(To)) + ? FromIsSmaller + : FromIsNotSmaller> +struct UnsignedSignedCheck; + +template<typename From, typename To> +struct UnsignedSignedCheck<From, To, FromIsSmaller> +{ +public: + static bool checkBounds(const From aFrom) + { + return true; + } +}; + +template<typename From, typename To> +struct UnsignedSignedCheck<From, To, FromIsNotSmaller> +{ +public: + static bool checkBounds(const From aFrom) + { + const To MaxValue = To((1ULL << (CHAR_BIT * sizeof(To) - 1)) - 1); + return aFrom <= From(MaxValue); + } +}; + +template<typename From, typename To> +struct BoundsCheckImpl<From, To, FromIsUnsigned, ToIsSigned> +{ +public: + static bool checkBounds(const From aFrom) + { + return UnsignedSignedCheck<From, To>::checkBounds(aFrom); + } +}; + +// Signed-to-signed range check + +template<typename From, typename To> +struct BoundsCheckImpl<From, To, FromIsSigned, ToIsSigned> +{ +public: + static bool checkBounds(const From aFrom) + { + if (sizeof(From) <= sizeof(To)) { + return true; + } + const To MaxValue = To((1ULL << (CHAR_BIT * sizeof(To) - 1)) - 1); + const To MinValue = -MaxValue - To(1); + return From(MinValue) <= aFrom && + From(aFrom) <= From(MaxValue); + } +}; + +template<typename From, typename To, + bool TypesAreIntegral = IsIntegral<From>::value && + IsIntegral<To>::value> +class BoundsChecker; + +template<typename From> +class BoundsChecker<From, From, true> +{ +public: + static bool checkBounds(const From aFrom) { return true; } +}; + +template<typename From, typename To> +class BoundsChecker<From, To, true> +{ +public: + static bool checkBounds(const From aFrom) + { + return BoundsCheckImpl<From, To>::checkBounds(aFrom); + } +}; + +template<typename From, typename To> +inline bool +IsInBounds(const From aFrom) +{ + return BoundsChecker<From, To>::checkBounds(aFrom); +} + +} // namespace detail + +/** + * Cast a value of integral type |From| to a value of integral type |To|, + * asserting that the cast will be a safe cast per C++ (that is, that |to| is in + * the range of values permitted for the type |From|). + */ +template<typename To, typename From> +inline To +AssertedCast(const From aFrom) +{ + MOZ_ASSERT((detail::IsInBounds<From, To>(aFrom))); + return static_cast<To>(aFrom); +} + +} // namespace mozilla + +#endif /* mozilla_Casting_h */ diff --git a/mfbt/ChaosMode.cpp b/mfbt/ChaosMode.cpp new file mode 100644 index 000000000..48ed093e2 --- /dev/null +++ b/mfbt/ChaosMode.cpp @@ -0,0 +1,17 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/ChaosMode.h" + +namespace mozilla { + +namespace detail { + +Atomic<uint32_t> gChaosModeCounter(0); +ChaosFeature gChaosFeatures = None; + +} /* namespace detail */ +} /* namespace mozilla */ diff --git a/mfbt/ChaosMode.h b/mfbt/ChaosMode.h new file mode 100644 index 000000000..94833c398 --- /dev/null +++ b/mfbt/ChaosMode.h @@ -0,0 +1,94 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef mozilla_ChaosMode_h +#define mozilla_ChaosMode_h + +#include "mozilla/Atomics.h" +#include "mozilla/EnumSet.h" + +#include <stdint.h> +#include <stdlib.h> + +namespace mozilla { + +enum ChaosFeature { + None = 0x0, + // Altering thread scheduling. + ThreadScheduling = 0x1, + // Altering network request scheduling. + NetworkScheduling = 0x2, + // Altering timer scheduling. + TimerScheduling = 0x4, + // Read and write less-than-requested amounts. + IOAmounts = 0x8, + // Iterate over hash tables in random order. + HashTableIteration = 0x10, + // Randomly refuse to use cached version of image (when allowed by spec). + ImageCache = 0x20, + Any = 0xffffffff, +}; + +namespace detail { +extern MFBT_DATA Atomic<uint32_t> gChaosModeCounter; +extern MFBT_DATA ChaosFeature gChaosFeatures; +} // namespace detail + +/** + * When "chaos mode" is activated, code that makes implicitly nondeterministic + * choices is encouraged to make random and extreme choices, to test more + * code paths and uncover bugs. + */ +class ChaosMode +{ +public: + static void SetChaosFeature(ChaosFeature aChaosFeature) + { + detail::gChaosFeatures = aChaosFeature; + } + + static bool isActive(ChaosFeature aFeature) + { + if (detail::gChaosModeCounter > 0) { + return true; + } + return detail::gChaosFeatures & aFeature; + } + + /** + * Increase the chaos mode activation level. An equivalent number of + * calls to leaveChaosMode must be made in order to restore the original + * chaos mode state. If the activation level is nonzero all chaos mode + * features are activated. + */ + static void enterChaosMode() + { + detail::gChaosModeCounter++; + } + + /** + * Decrease the chaos mode activation level. See enterChaosMode(). + */ + static void leaveChaosMode() + { + MOZ_ASSERT(detail::gChaosModeCounter > 0); + detail::gChaosModeCounter--; + } + + /** + * Returns a somewhat (but not uniformly) random uint32_t < aBound. + * Not to be used for anything except ChaosMode, since it's not very random. + */ + static uint32_t randomUint32LessThan(uint32_t aBound) + { + MOZ_ASSERT(aBound != 0); + return uint32_t(rand()) % aBound; + } +}; + +} /* namespace mozilla */ + +#endif /* mozilla_ChaosMode_h */ diff --git a/mfbt/Char16.h b/mfbt/Char16.h new file mode 100644 index 000000000..3c2f254aa --- /dev/null +++ b/mfbt/Char16.h @@ -0,0 +1,194 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Implements a UTF-16 character type. */ + +#ifndef mozilla_Char16_h +#define mozilla_Char16_h + +#ifdef __cplusplus + +/* + * C++11 introduces a char16_t type and support for UTF-16 string and character + * literals. C++11's char16_t is a distinct builtin type. Technically, char16_t + * is a 16-bit code unit of a Unicode code point, not a "character". + */ + +#ifdef WIN32 +# define MOZ_USE_CHAR16_WRAPPER +# include <cstdint> + /** + * Win32 API extensively uses wchar_t, which is represented by a separated + * builtin type than char16_t per spec. It's not the case for MSVC prior to + * MSVC 2015, but other compilers follow the spec. We want to mix wchar_t and + * char16_t on Windows builds. This class is supposed to make it easier. It + * stores char16_t const pointer, but provides implicit casts for wchar_t as + * well. On other platforms, we simply use + * |typedef const char16_t* char16ptr_t|. Here, we want to make the class as + * similar to this typedef, including providing some casts that are allowed + * by the typedef. + */ +class char16ptr_t +{ +private: + const char16_t* mPtr; + static_assert(sizeof(char16_t) == sizeof(wchar_t), + "char16_t and wchar_t sizes differ"); + +public: + char16ptr_t(const char16_t* aPtr) : mPtr(aPtr) {} + char16ptr_t(const wchar_t* aPtr) : + mPtr(reinterpret_cast<const char16_t*>(aPtr)) + {} + + /* Without this, nullptr assignment would be ambiguous. */ + constexpr char16ptr_t(decltype(nullptr)) : mPtr(nullptr) {} + + operator const char16_t*() const + { + return mPtr; + } + operator const wchar_t*() const + { + return reinterpret_cast<const wchar_t*>(mPtr); + } + operator const void*() const + { + return mPtr; + } + operator bool() const + { + return mPtr != nullptr; + } + + /* Explicit cast operators to allow things like (char16_t*)str. */ + explicit operator char16_t*() const + { + return const_cast<char16_t*>(mPtr); + } + explicit operator wchar_t*() const + { + return const_cast<wchar_t*>(static_cast<const wchar_t*>(*this)); + } + explicit operator int() const + { + return reinterpret_cast<intptr_t>(mPtr); + } + explicit operator unsigned int() const + { + return reinterpret_cast<uintptr_t>(mPtr); + } + explicit operator long() const + { + return reinterpret_cast<intptr_t>(mPtr); + } + explicit operator unsigned long() const + { + return reinterpret_cast<uintptr_t>(mPtr); + } + explicit operator long long() const + { + return reinterpret_cast<intptr_t>(mPtr); + } + explicit operator unsigned long long() const + { + return reinterpret_cast<uintptr_t>(mPtr); + } + + /** + * Some Windows API calls accept BYTE* but require that data actually be + * WCHAR*. Supporting this requires explicit operators to support the + * requisite explicit casts. + */ + explicit operator const char*() const + { + return reinterpret_cast<const char*>(mPtr); + } + explicit operator const unsigned char*() const + { + return reinterpret_cast<const unsigned char*>(mPtr); + } + explicit operator unsigned char*() const + { + return + const_cast<unsigned char*>(reinterpret_cast<const unsigned char*>(mPtr)); + } + explicit operator void*() const + { + return const_cast<char16_t*>(mPtr); + } + + /* Some operators used on pointers. */ + char16_t operator[](size_t aIndex) const + { + return mPtr[aIndex]; + } + bool operator==(const char16ptr_t& aOther) const + { + return mPtr == aOther.mPtr; + } + bool operator==(decltype(nullptr)) const + { + return mPtr == nullptr; + } + bool operator!=(const char16ptr_t& aOther) const + { + return mPtr != aOther.mPtr; + } + bool operator!=(decltype(nullptr)) const + { + return mPtr != nullptr; + } + char16ptr_t operator+(int aValue) const + { + return char16ptr_t(mPtr + aValue); + } + char16ptr_t operator+(unsigned int aValue) const + { + return char16ptr_t(mPtr + aValue); + } + char16ptr_t operator+(long aValue) const + { + return char16ptr_t(mPtr + aValue); + } + char16ptr_t operator+(unsigned long aValue) const + { + return char16ptr_t(mPtr + aValue); + } + char16ptr_t operator+(long long aValue) const + { + return char16ptr_t(mPtr + aValue); + } + char16ptr_t operator+(unsigned long long aValue) const + { + return char16ptr_t(mPtr + aValue); + } + ptrdiff_t operator-(const char16ptr_t& aOther) const + { + return mPtr - aOther.mPtr; + } +}; + +inline decltype((char*)0-(char*)0) +operator-(const char16_t* aX, const char16ptr_t aY) +{ + return aX - static_cast<const char16_t*>(aY); +} + +#else + +typedef const char16_t* char16ptr_t; + +#endif + +static_assert(sizeof(char16_t) == 2, "Is char16_t type 16 bits?"); +static_assert(char16_t(-1) > char16_t(0), "Is char16_t type unsigned?"); +static_assert(sizeof(u'A') == 2, "Is unicode char literal 16 bits?"); +static_assert(sizeof(u""[0]) == 2, "Is unicode string char 16 bits?"); + +#endif + +#endif /* mozilla_Char16_h */ diff --git a/mfbt/CheckedInt.h b/mfbt/CheckedInt.h new file mode 100644 index 000000000..02ef8d5b7 --- /dev/null +++ b/mfbt/CheckedInt.h @@ -0,0 +1,791 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Provides checked integers, detecting integer overflow and divide-by-0. */ + +#ifndef mozilla_CheckedInt_h +#define mozilla_CheckedInt_h + +#include <stdint.h> +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" +#include "mozilla/IntegerTypeTraits.h" + +namespace mozilla { + +template<typename T> class CheckedInt; + +namespace detail { + +/* + * Step 1: manually record supported types + * + * What's nontrivial here is that there are different families of integer + * types: basic integer types and stdint types. It is merrily undefined which + * types from one family may be just typedefs for a type from another family. + * + * For example, on GCC 4.6, aside from the basic integer types, the only other + * type that isn't just a typedef for some of them, is int8_t. + */ + +struct UnsupportedType {}; + +template<typename IntegerType> +struct IsSupportedPass2 +{ + static const bool value = false; +}; + +template<typename IntegerType> +struct IsSupported +{ + static const bool value = IsSupportedPass2<IntegerType>::value; +}; + +template<> +struct IsSupported<int8_t> +{ static const bool value = true; }; + +template<> +struct IsSupported<uint8_t> +{ static const bool value = true; }; + +template<> +struct IsSupported<int16_t> +{ static const bool value = true; }; + +template<> +struct IsSupported<uint16_t> +{ static const bool value = true; }; + +template<> +struct IsSupported<int32_t> +{ static const bool value = true; }; + +template<> +struct IsSupported<uint32_t> +{ static const bool value = true; }; + +template<> +struct IsSupported<int64_t> +{ static const bool value = true; }; + +template<> +struct IsSupported<uint64_t> +{ static const bool value = true; }; + + +template<> +struct IsSupportedPass2<char> +{ static const bool value = true; }; + +template<> +struct IsSupportedPass2<signed char> +{ static const bool value = true; }; + +template<> +struct IsSupportedPass2<unsigned char> +{ static const bool value = true; }; + +template<> +struct IsSupportedPass2<short> +{ static const bool value = true; }; + +template<> +struct IsSupportedPass2<unsigned short> +{ static const bool value = true; }; + +template<> +struct IsSupportedPass2<int> +{ static const bool value = true; }; + +template<> +struct IsSupportedPass2<unsigned int> +{ static const bool value = true; }; + +template<> +struct IsSupportedPass2<long> +{ static const bool value = true; }; + +template<> +struct IsSupportedPass2<unsigned long> +{ static const bool value = true; }; + +template<> +struct IsSupportedPass2<long long> +{ static const bool value = true; }; + +template<> +struct IsSupportedPass2<unsigned long long> +{ static const bool value = true; }; + +/* + * Step 2: Implement the actual validity checks. + * + * Ideas taken from IntegerLib, code different. + */ + +template<typename IntegerType, size_t Size = sizeof(IntegerType)> +struct TwiceBiggerType +{ + typedef typename detail::StdintTypeForSizeAndSignedness< + sizeof(IntegerType) * 2, + IsSigned<IntegerType>::value + >::Type Type; +}; + +template<typename IntegerType> +struct TwiceBiggerType<IntegerType, 8> +{ + typedef UnsupportedType Type; +}; + +template<typename T> +inline bool +HasSignBit(T aX) +{ + // In C++, right bit shifts on negative values is undefined by the standard. + // Notice that signed-to-unsigned conversions are always well-defined in the + // standard, as the value congruent modulo 2**n as expected. By contrast, + // unsigned-to-signed is only well-defined if the value is representable. + return bool(typename MakeUnsigned<T>::Type(aX) >> + PositionOfSignBit<T>::value); +} + +// Bitwise ops may return a larger type, so it's good to use this inline +// helper guaranteeing that the result is really of type T. +template<typename T> +inline T +BinaryComplement(T aX) +{ + return ~aX; +} + +template<typename T, + typename U, + bool IsTSigned = IsSigned<T>::value, + bool IsUSigned = IsSigned<U>::value> +struct DoesRangeContainRange +{ +}; + +template<typename T, typename U, bool Signedness> +struct DoesRangeContainRange<T, U, Signedness, Signedness> +{ + static const bool value = sizeof(T) >= sizeof(U); +}; + +template<typename T, typename U> +struct DoesRangeContainRange<T, U, true, false> +{ + static const bool value = sizeof(T) > sizeof(U); +}; + +template<typename T, typename U> +struct DoesRangeContainRange<T, U, false, true> +{ + static const bool value = false; +}; + +template<typename T, + typename U, + bool IsTSigned = IsSigned<T>::value, + bool IsUSigned = IsSigned<U>::value, + bool DoesTRangeContainURange = DoesRangeContainRange<T, U>::value> +struct IsInRangeImpl {}; + +template<typename T, typename U, bool IsTSigned, bool IsUSigned> +struct IsInRangeImpl<T, U, IsTSigned, IsUSigned, true> +{ + static bool run(U) + { + return true; + } +}; + +template<typename T, typename U> +struct IsInRangeImpl<T, U, true, true, false> +{ + static bool run(U aX) + { + return aX <= MaxValue<T>::value && aX >= MinValue<T>::value; + } +}; + +template<typename T, typename U> +struct IsInRangeImpl<T, U, false, false, false> +{ + static bool run(U aX) + { + return aX <= MaxValue<T>::value; + } +}; + +template<typename T, typename U> +struct IsInRangeImpl<T, U, true, false, false> +{ + static bool run(U aX) + { + return sizeof(T) > sizeof(U) || aX <= U(MaxValue<T>::value); + } +}; + +template<typename T, typename U> +struct IsInRangeImpl<T, U, false, true, false> +{ + static bool run(U aX) + { + return sizeof(T) >= sizeof(U) + ? aX >= 0 + : aX >= 0 && aX <= U(MaxValue<T>::value); + } +}; + +template<typename T, typename U> +inline bool +IsInRange(U aX) +{ + return IsInRangeImpl<T, U>::run(aX); +} + +template<typename T> +inline bool +IsAddValid(T aX, T aY) +{ + // Addition is valid if the sign of aX+aY is equal to either that of aX or + // that of aY. Since the value of aX+aY is undefined if we have a signed + // type, we compute it using the unsigned type of the same size. Beware! + // These bitwise operations can return a larger integer type, if T was a + // small type like int8_t, so we explicitly cast to T. + + typename MakeUnsigned<T>::Type ux = aX; + typename MakeUnsigned<T>::Type uy = aY; + typename MakeUnsigned<T>::Type result = ux + uy; + return IsSigned<T>::value + ? HasSignBit(BinaryComplement(T((result ^ aX) & (result ^ aY)))) + : BinaryComplement(aX) >= aY; +} + +template<typename T> +inline bool +IsSubValid(T aX, T aY) +{ + // Subtraction is valid if either aX and aY have same sign, or aX-aY and aX + // have same sign. Since the value of aX-aY is undefined if we have a signed + // type, we compute it using the unsigned type of the same size. + typename MakeUnsigned<T>::Type ux = aX; + typename MakeUnsigned<T>::Type uy = aY; + typename MakeUnsigned<T>::Type result = ux - uy; + + return IsSigned<T>::value + ? HasSignBit(BinaryComplement(T((result ^ aX) & (aX ^ aY)))) + : aX >= aY; +} + +template<typename T, + bool IsTSigned = IsSigned<T>::value, + bool TwiceBiggerTypeIsSupported = + IsSupported<typename TwiceBiggerType<T>::Type>::value> +struct IsMulValidImpl {}; + +template<typename T, bool IsTSigned> +struct IsMulValidImpl<T, IsTSigned, true> +{ + static bool run(T aX, T aY) + { + typedef typename TwiceBiggerType<T>::Type TwiceBiggerType; + TwiceBiggerType product = TwiceBiggerType(aX) * TwiceBiggerType(aY); + return IsInRange<T>(product); + } +}; + +template<typename T> +struct IsMulValidImpl<T, true, false> +{ + static bool run(T aX, T aY) + { + const T max = MaxValue<T>::value; + const T min = MinValue<T>::value; + + if (aX == 0 || aY == 0) { + return true; + } + if (aX > 0) { + return aY > 0 + ? aX <= max / aY + : aY >= min / aX; + } + + // If we reach this point, we know that aX < 0. + return aY > 0 + ? aX >= min / aY + : aY >= max / aX; + } +}; + +template<typename T> +struct IsMulValidImpl<T, false, false> +{ + static bool run(T aX, T aY) + { + return aY == 0 || aX <= MaxValue<T>::value / aY; + } +}; + +template<typename T> +inline bool +IsMulValid(T aX, T aY) +{ + return IsMulValidImpl<T>::run(aX, aY); +} + +template<typename T> +inline bool +IsDivValid(T aX, T aY) +{ + // Keep in mind that in the signed case, min/-1 is invalid because + // abs(min)>max. + return aY != 0 && + !(IsSigned<T>::value && aX == MinValue<T>::value && aY == T(-1)); +} + +template<typename T, bool IsTSigned = IsSigned<T>::value> +struct IsModValidImpl; + +template<typename T> +inline bool +IsModValid(T aX, T aY) +{ + return IsModValidImpl<T>::run(aX, aY); +} + +/* + * Mod is pretty simple. + * For now, let's just use the ANSI C definition: + * If aX or aY are negative, the results are implementation defined. + * Consider these invalid. + * Undefined for aY=0. + * The result will never exceed either aX or aY. + * + * Checking that aX>=0 is a warning when T is unsigned. + */ + +template<typename T> +struct IsModValidImpl<T, false> +{ + static inline bool run(T aX, T aY) + { + return aY >= 1; + } +}; + +template<typename T> +struct IsModValidImpl<T, true> +{ + static inline bool run(T aX, T aY) + { + if (aX < 0) { + return false; + } + return aY >= 1; + } +}; + +template<typename T, bool IsSigned = IsSigned<T>::value> +struct NegateImpl; + +template<typename T> +struct NegateImpl<T, false> +{ + static CheckedInt<T> negate(const CheckedInt<T>& aVal) + { + // Handle negation separately for signed/unsigned, for simpler code and to + // avoid an MSVC warning negating an unsigned value. + return CheckedInt<T>(0, aVal.isValid() && aVal.mValue == 0); + } +}; + +template<typename T> +struct NegateImpl<T, true> +{ + static CheckedInt<T> negate(const CheckedInt<T>& aVal) + { + // Watch out for the min-value, which (with twos-complement) can't be + // negated as -min-value is then (max-value + 1). + if (!aVal.isValid() || aVal.mValue == MinValue<T>::value) { + return CheckedInt<T>(aVal.mValue, false); + } + return CheckedInt<T>(-aVal.mValue, true); + } +}; + +} // namespace detail + + +/* + * Step 3: Now define the CheckedInt class. + */ + +/** + * @class CheckedInt + * @brief Integer wrapper class checking for integer overflow and other errors + * @param T the integer type to wrap. Can be any type among the following: + * - any basic integer type such as |int| + * - any stdint type such as |int8_t| + * + * This class implements guarded integer arithmetic. Do a computation, check + * that isValid() returns true, you then have a guarantee that no problem, such + * as integer overflow, happened during this computation, and you can call + * value() to get the plain integer value. + * + * The arithmetic operators in this class are guaranteed not to raise a signal + * (e.g. in case of a division by zero). + * + * For example, suppose that you want to implement a function that computes + * (aX+aY)/aZ, that doesn't crash if aZ==0, and that reports on error (divide by + * zero or integer overflow). You could code it as follows: + @code + bool computeXPlusYOverZ(int aX, int aY, int aZ, int* aResult) + { + CheckedInt<int> checkedResult = (CheckedInt<int>(aX) + aY) / aZ; + if (checkedResult.isValid()) { + *aResult = checkedResult.value(); + return true; + } else { + return false; + } + } + @endcode + * + * Implicit conversion from plain integers to checked integers is allowed. The + * plain integer is checked to be in range before being casted to the + * destination type. This means that the following lines all compile, and the + * resulting CheckedInts are correctly detected as valid or invalid: + * @code + // 1 is of type int, is found to be in range for uint8_t, x is valid + CheckedInt<uint8_t> x(1); + // -1 is of type int, is found not to be in range for uint8_t, x is invalid + CheckedInt<uint8_t> x(-1); + // -1 is of type int, is found to be in range for int8_t, x is valid + CheckedInt<int8_t> x(-1); + // 1000 is of type int16_t, is found not to be in range for int8_t, + // x is invalid + CheckedInt<int8_t> x(int16_t(1000)); + // 3123456789 is of type uint32_t, is found not to be in range for int32_t, + // x is invalid + CheckedInt<int32_t> x(uint32_t(3123456789)); + * @endcode + * Implicit conversion from + * checked integers to plain integers is not allowed. As shown in the + * above example, to get the value of a checked integer as a normal integer, + * call value(). + * + * Arithmetic operations between checked and plain integers is allowed; the + * result type is the type of the checked integer. + * + * Checked integers of different types cannot be used in the same arithmetic + * expression. + * + * There are convenience typedefs for all stdint types, of the following form + * (these are just 2 examples): + @code + typedef CheckedInt<int32_t> CheckedInt32; + typedef CheckedInt<uint16_t> CheckedUint16; + @endcode + */ +template<typename T> +class CheckedInt +{ +protected: + T mValue; + bool mIsValid; + + template<typename U> + CheckedInt(U aValue, bool aIsValid) : mValue(aValue), mIsValid(aIsValid) + { + static_assert(detail::IsSupported<T>::value && + detail::IsSupported<U>::value, + "This type is not supported by CheckedInt"); + } + + friend struct detail::NegateImpl<T>; + +public: + /** + * Constructs a checked integer with given @a value. The checked integer is + * initialized as valid or invalid depending on whether the @a value + * is in range. + * + * This constructor is not explicit. Instead, the type of its argument is a + * separate template parameter, ensuring that no conversion is performed + * before this constructor is actually called. As explained in the above + * documentation for class CheckedInt, this constructor checks that its + * argument is valid. + */ + template<typename U> + MOZ_IMPLICIT CheckedInt(U aValue) MOZ_NO_ARITHMETIC_EXPR_IN_ARGUMENT + : mValue(T(aValue)), + mIsValid(detail::IsInRange<T>(aValue)) + { + static_assert(detail::IsSupported<T>::value && + detail::IsSupported<U>::value, + "This type is not supported by CheckedInt"); + } + + template<typename U> + friend class CheckedInt; + + template<typename U> + CheckedInt<U> toChecked() const + { + CheckedInt<U> ret(mValue); + ret.mIsValid = ret.mIsValid && mIsValid; + return ret; + } + + /** Constructs a valid checked integer with initial value 0 */ + CheckedInt() : mValue(0), mIsValid(true) + { + static_assert(detail::IsSupported<T>::value, + "This type is not supported by CheckedInt"); + } + + /** @returns the actual value */ + T value() const + { + MOZ_ASSERT(mIsValid, "Invalid checked integer (division by zero or integer overflow)"); + return mValue; + } + + /** + * @returns true if the checked integer is valid, i.e. is not the result + * of an invalid operation or of an operation involving an invalid checked + * integer + */ + bool isValid() const + { + return mIsValid; + } + + template<typename U> + friend CheckedInt<U> operator +(const CheckedInt<U>& aLhs, + const CheckedInt<U>& aRhs); + template<typename U> + CheckedInt& operator +=(U aRhs); + CheckedInt& operator +=(const CheckedInt<T>& aRhs); + + template<typename U> + friend CheckedInt<U> operator -(const CheckedInt<U>& aLhs, + const CheckedInt<U>& aRhs); + template<typename U> + CheckedInt& operator -=(U aRhs); + CheckedInt& operator -=(const CheckedInt<T>& aRhs); + + template<typename U> + friend CheckedInt<U> operator *(const CheckedInt<U>& aLhs, + const CheckedInt<U>& aRhs); + template<typename U> + CheckedInt& operator *=(U aRhs); + CheckedInt& operator *=(const CheckedInt<T>& aRhs); + + template<typename U> + friend CheckedInt<U> operator /(const CheckedInt<U>& aLhs, + const CheckedInt<U>& aRhs); + template<typename U> + CheckedInt& operator /=(U aRhs); + CheckedInt& operator /=(const CheckedInt<T>& aRhs); + + template<typename U> + friend CheckedInt<U> operator %(const CheckedInt<U>& aLhs, + const CheckedInt<U>& aRhs); + template<typename U> + CheckedInt& operator %=(U aRhs); + CheckedInt& operator %=(const CheckedInt<T>& aRhs); + + CheckedInt operator -() const + { + return detail::NegateImpl<T>::negate(*this); + } + + /** + * @returns true if the left and right hand sides are valid + * and have the same value. + * + * Note that these semantics are the reason why we don't offer + * a operator!=. Indeed, we'd want to have a!=b be equivalent to !(a==b) + * but that would mean that whenever a or b is invalid, a!=b + * is always true, which would be very confusing. + * + * For similar reasons, operators <, >, <=, >= would be very tricky to + * specify, so we just avoid offering them. + * + * Notice that these == semantics are made more reasonable by these facts: + * 1. a==b implies equality at the raw data level + * (the converse is false, as a==b is never true among invalids) + * 2. This is similar to the behavior of IEEE floats, where a==b + * means that a and b have the same value *and* neither is NaN. + */ + bool operator ==(const CheckedInt& aOther) const + { + return mIsValid && aOther.mIsValid && mValue == aOther.mValue; + } + + /** prefix ++ */ + CheckedInt& operator++() + { + *this += 1; + return *this; + } + + /** postfix ++ */ + CheckedInt operator++(int) + { + CheckedInt tmp = *this; + *this += 1; + return tmp; + } + + /** prefix -- */ + CheckedInt& operator--() + { + *this -= 1; + return *this; + } + + /** postfix -- */ + CheckedInt operator--(int) + { + CheckedInt tmp = *this; + *this -= 1; + return tmp; + } + +private: + /** + * The !=, <, <=, >, >= operators are disabled: + * see the comment on operator==. + */ + template<typename U> bool operator !=(U aOther) const = delete; + template<typename U> bool operator < (U aOther) const = delete; + template<typename U> bool operator <=(U aOther) const = delete; + template<typename U> bool operator > (U aOther) const = delete; + template<typename U> bool operator >=(U aOther) const = delete; +}; + +#define MOZ_CHECKEDINT_BASIC_BINARY_OPERATOR(NAME, OP) \ + template<typename T> \ + inline CheckedInt<T> \ + operator OP(const CheckedInt<T>& aLhs, const CheckedInt<T>& aRhs) \ + { \ + if (!detail::Is##NAME##Valid(aLhs.mValue, aRhs.mValue)) { \ + return CheckedInt<T>(0, false); \ + } \ + return CheckedInt<T>(aLhs.mValue OP aRhs.mValue, \ + aLhs.mIsValid && aRhs.mIsValid); \ + } + +MOZ_CHECKEDINT_BASIC_BINARY_OPERATOR(Add, +) +MOZ_CHECKEDINT_BASIC_BINARY_OPERATOR(Sub, -) +MOZ_CHECKEDINT_BASIC_BINARY_OPERATOR(Mul, *) +MOZ_CHECKEDINT_BASIC_BINARY_OPERATOR(Div, /) +MOZ_CHECKEDINT_BASIC_BINARY_OPERATOR(Mod, %) + +#undef MOZ_CHECKEDINT_BASIC_BINARY_OPERATOR + +// Implement castToCheckedInt<T>(x), making sure that +// - it allows x to be either a CheckedInt<T> or any integer type +// that can be casted to T +// - if x is already a CheckedInt<T>, we just return a reference to it, +// instead of copying it (optimization) + +namespace detail { + +template<typename T, typename U> +struct CastToCheckedIntImpl +{ + typedef CheckedInt<T> ReturnType; + static CheckedInt<T> run(U aU) { return aU; } +}; + +template<typename T> +struct CastToCheckedIntImpl<T, CheckedInt<T> > +{ + typedef const CheckedInt<T>& ReturnType; + static const CheckedInt<T>& run(const CheckedInt<T>& aU) { return aU; } +}; + +} // namespace detail + +template<typename T, typename U> +inline typename detail::CastToCheckedIntImpl<T, U>::ReturnType +castToCheckedInt(U aU) +{ + static_assert(detail::IsSupported<T>::value && + detail::IsSupported<U>::value, + "This type is not supported by CheckedInt"); + return detail::CastToCheckedIntImpl<T, U>::run(aU); +} + +#define MOZ_CHECKEDINT_CONVENIENCE_BINARY_OPERATORS(OP, COMPOUND_OP) \ + template<typename T> \ + template<typename U> \ + CheckedInt<T>& CheckedInt<T>::operator COMPOUND_OP(U aRhs) \ + { \ + *this = *this OP castToCheckedInt<T>(aRhs); \ + return *this; \ + } \ + template<typename T> \ + CheckedInt<T>& CheckedInt<T>::operator COMPOUND_OP(const CheckedInt<T>& aRhs) \ + { \ + *this = *this OP aRhs; \ + return *this; \ + } \ + template<typename T, typename U> \ + inline CheckedInt<T> operator OP(const CheckedInt<T>& aLhs, U aRhs) \ + { \ + return aLhs OP castToCheckedInt<T>(aRhs); \ + } \ + template<typename T, typename U> \ + inline CheckedInt<T> operator OP(U aLhs, const CheckedInt<T>& aRhs) \ + { \ + return castToCheckedInt<T>(aLhs) OP aRhs; \ + } + +MOZ_CHECKEDINT_CONVENIENCE_BINARY_OPERATORS(+, +=) +MOZ_CHECKEDINT_CONVENIENCE_BINARY_OPERATORS(*, *=) +MOZ_CHECKEDINT_CONVENIENCE_BINARY_OPERATORS(-, -=) +MOZ_CHECKEDINT_CONVENIENCE_BINARY_OPERATORS(/, /=) +MOZ_CHECKEDINT_CONVENIENCE_BINARY_OPERATORS(%, %=) + +#undef MOZ_CHECKEDINT_CONVENIENCE_BINARY_OPERATORS + +template<typename T, typename U> +inline bool +operator ==(const CheckedInt<T>& aLhs, U aRhs) +{ + return aLhs == castToCheckedInt<T>(aRhs); +} + +template<typename T, typename U> +inline bool +operator ==(U aLhs, const CheckedInt<T>& aRhs) +{ + return castToCheckedInt<T>(aLhs) == aRhs; +} + +// Convenience typedefs. +typedef CheckedInt<int8_t> CheckedInt8; +typedef CheckedInt<uint8_t> CheckedUint8; +typedef CheckedInt<int16_t> CheckedInt16; +typedef CheckedInt<uint16_t> CheckedUint16; +typedef CheckedInt<int32_t> CheckedInt32; +typedef CheckedInt<uint32_t> CheckedUint32; +typedef CheckedInt<int64_t> CheckedInt64; +typedef CheckedInt<uint64_t> CheckedUint64; + +} // namespace mozilla + +#endif /* mozilla_CheckedInt_h */ diff --git a/mfbt/Compiler.h b/mfbt/Compiler.h new file mode 100644 index 000000000..1bd34d329 --- /dev/null +++ b/mfbt/Compiler.h @@ -0,0 +1,113 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Various compiler checks. */ + +#ifndef mozilla_Compiler_h +#define mozilla_Compiler_h + +#define MOZ_IS_GCC 0 +#define MOZ_IS_MSVC 0 + +#if !defined(__clang__) && defined(__GNUC__) + +# undef MOZ_IS_GCC +# define MOZ_IS_GCC 1 + /* + * These macros should simplify gcc version checking. For example, to check + * for gcc 4.7.1 or later, check `#if MOZ_GCC_VERSION_AT_LEAST(4, 7, 1)`. + */ +# define MOZ_GCC_VERSION_AT_LEAST(major, minor, patchlevel) \ + ((__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) \ + >= ((major) * 10000 + (minor) * 100 + (patchlevel))) +# define MOZ_GCC_VERSION_AT_MOST(major, minor, patchlevel) \ + ((__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) \ + <= ((major) * 10000 + (minor) * 100 + (patchlevel))) +# if !MOZ_GCC_VERSION_AT_LEAST(4, 8, 0) +# error "mfbt (and Gecko) require at least gcc 4.8 to build." +# endif + +#elif defined(_MSC_VER) + +# undef MOZ_IS_MSVC +# define MOZ_IS_MSVC 1 + +#endif + +/* + * The situation with standard libraries is a lot worse than with compilers, + * particularly as clang and gcc could end up using one of three or so standard + * libraries, and they may not be up-to-snuff with newer C++11 versions. To + * detect the library, we're going to include cstddef (which is a small header + * which will be transitively included by everybody else at some point) to grab + * the version macros and deduce macros from there. + */ +#ifdef __cplusplus +# include <cstddef> +# ifdef _STLPORT_MAJOR +# define MOZ_USING_STLPORT 1 +# define MOZ_STLPORT_VERSION_AT_LEAST(major, minor, patch) \ + (_STLPORT_VERSION >= ((major) << 8 | (minor) << 4 | (patch))) +# elif defined(_LIBCPP_VERSION) + /* + * libc++, unfortunately, doesn't appear to have useful versioning macros. + * Hopefully, the recommendations of N3694 with respect to standard libraries + * will get applied instead and we won't need to worry about version numbers + * here. + */ +# define MOZ_USING_LIBCXX 1 +# elif defined(__GLIBCXX__) +# define MOZ_USING_LIBSTDCXX 1 + /* + * libstdc++ is also annoying and doesn't give us useful versioning macros + * for the library. If we're using gcc, then assume that libstdc++ matches + * the compiler version. If we're using clang, we're going to have to fake + * major/minor combinations by looking for newly-defined config macros. + */ +# if MOZ_IS_GCC +# define MOZ_LIBSTDCXX_VERSION_AT_LEAST(major, minor, patch) \ + MOZ_GCC_VERSION_AT_LEAST(major, minor, patch) +# elif defined(_GLIBCXX_THROW_OR_ABORT) +# define MOZ_LIBSTDCXX_VERSION_AT_LEAST(major, minor, patch) \ + ((major) < 4 || ((major) == 4 && (minor) <= 8)) +# elif defined(_GLIBCXX_NOEXCEPT) +# define MOZ_LIBSTDCXX_VERSION_AT_LEAST(major, minor, patch) \ + ((major) < 4 || ((major) == 4 && (minor) <= 7)) +# elif defined(_GLIBCXX_USE_DEPRECATED) +# define MOZ_LIBSTDCXX_VERSION_AT_LEAST(major, minor, patch) \ + ((major) < 4 || ((major) == 4 && (minor) <= 6)) +# elif defined(_GLIBCXX_PSEUDO_VISIBILITY) +# define MOZ_LIBSTDCXX_VERSION_AT_LEAST(major, minor, patch) \ + ((major) < 4 || ((major) == 4 && (minor) <= 5)) +# elif defined(_GLIBCXX_BEGIN_EXTERN_C) +# define MOZ_LIBSTDCXX_VERSION_AT_LEAST(major, minor, patch) \ + ((major) < 4 || ((major) == 4 && (minor) <= 4)) +# elif defined(_GLIBCXX_VISIBILITY_ATTR) +# define MOZ_LIBSTDCXX_VERSION_AT_LEAST(major, minor, patch) \ + ((major) < 4 || ((major) == 4 && (minor) <= 3)) +# elif defined(_GLIBCXX_VISIBILITY) +# define MOZ_LIBSTDCXX_VERSION_AT_LEAST(major, minor, patch) \ + ((major) < 4 || ((major) == 4 && (minor) <= 2)) +# else +# error "Your version of libstdc++ is unknown to us and is likely too old." +# endif +# endif + + // Flesh out the defines for everyone else +# ifndef MOZ_USING_STLPORT +# define MOZ_USING_STLPORT 0 +# define MOZ_STLPORT_VERSION_AT_LEAST(major, minor, patch) 0 +# endif +# ifndef MOZ_USING_LIBCXX +# define MOZ_USING_LIBCXX 0 +# endif +# ifndef MOZ_USING_LIBSTDCXX +# define MOZ_USING_LIBSTDCXX 0 +# define MOZ_LIBSTDCXX_VERSION_AT_LEAST(major, minor, patch) 0 +# endif +#endif /* __cplusplus */ + +#endif /* mozilla_Compiler_h */ diff --git a/mfbt/Compression.cpp b/mfbt/Compression.cpp new file mode 100644 index 000000000..c114c6c0f --- /dev/null +++ b/mfbt/Compression.cpp @@ -0,0 +1,73 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Compression.h" +#include "mozilla/CheckedInt.h" + +// Without including <string>, MSVC 2015 complains about e.g. the impossibility +// to convert `const void* const` to `void*` when calling memchr from +// corecrt_memory.h. +#include <string> + +using namespace mozilla::Compression; + +namespace { + +#include "lz4.c" + +}/* anonymous namespace */ + +/* Our wrappers */ + +size_t +LZ4::compress(const char* aSource, size_t aInputSize, char* aDest) +{ + CheckedInt<int> inputSizeChecked = aInputSize; + MOZ_ASSERT(inputSizeChecked.isValid()); + return LZ4_compress(aSource, aDest, inputSizeChecked.value()); +} + +size_t +LZ4::compressLimitedOutput(const char* aSource, size_t aInputSize, char* aDest, + size_t aMaxOutputSize) +{ + CheckedInt<int> inputSizeChecked = aInputSize; + MOZ_ASSERT(inputSizeChecked.isValid()); + CheckedInt<int> maxOutputSizeChecked = aMaxOutputSize; + MOZ_ASSERT(maxOutputSizeChecked.isValid()); + return LZ4_compress_limitedOutput(aSource, aDest, inputSizeChecked.value(), + maxOutputSizeChecked.value()); +} + +bool +LZ4::decompress(const char* aSource, char* aDest, size_t aOutputSize) +{ + CheckedInt<int> outputSizeChecked = aOutputSize; + MOZ_ASSERT(outputSizeChecked.isValid()); + int ret = LZ4_decompress_fast(aSource, aDest, outputSizeChecked.value()); + return ret >= 0; +} + +bool +LZ4::decompress(const char* aSource, size_t aInputSize, char* aDest, + size_t aMaxOutputSize, size_t* aOutputSize) +{ + CheckedInt<int> maxOutputSizeChecked = aMaxOutputSize; + MOZ_ASSERT(maxOutputSizeChecked.isValid()); + CheckedInt<int> inputSizeChecked = aInputSize; + MOZ_ASSERT(inputSizeChecked.isValid()); + + int ret = LZ4_decompress_safe(aSource, aDest, inputSizeChecked.value(), + maxOutputSizeChecked.value()); + if (ret >= 0) { + *aOutputSize = ret; + return true; + } + + *aOutputSize = 0; + return false; +} + diff --git a/mfbt/Compression.h b/mfbt/Compression.h new file mode 100644 index 000000000..aa50211b3 --- /dev/null +++ b/mfbt/Compression.h @@ -0,0 +1,119 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Various simple compression/decompression functions. */ + +#ifndef mozilla_Compression_h_ +#define mozilla_Compression_h_ + +#include "mozilla/Assertions.h" +#include "mozilla/Types.h" + +namespace mozilla { +namespace Compression { + +/** + * LZ4 is a very fast byte-wise compression algorithm. + * + * Compared to Google's Snappy it is faster to compress and decompress and + * generally produces output of about the same size. + * + * Compared to zlib it compresses at about 10x the speed, decompresses at about + * 4x the speed and produces output of about 1.5x the size. + */ + +class LZ4 +{ +public: + /** + * Compresses |aInputSize| bytes from |aSource| into |aDest|. Destination + * buffer must be already allocated, and must be sized to handle worst cases + * situations (input data not compressible). Worst case size evaluation is + * provided by function maxCompressedSize() + * + * @param aInputSize is the input size. Max supported value is ~1.9GB + * @return the number of bytes written in buffer |aDest| + */ + static MFBT_API size_t + compress(const char* aSource, size_t aInputSize, char* aDest); + + /** + * Compress |aInputSize| bytes from |aSource| into an output buffer + * |aDest| of maximum size |aMaxOutputSize|. If it cannot achieve it, + * compression will stop, and result of the function will be zero, + * |aDest| will still be written to, but since the number of input + * bytes consumed is not returned the result is not usable. + * + * This function never writes outside of provided output buffer. + * + * @param aInputSize is the input size. Max supported value is ~1.9GB + * @param aMaxOutputSize is the size of the destination buffer (which must + * be already allocated) + * @return the number of bytes written in buffer |aDest| or 0 if the + * compression fails + */ + static MFBT_API size_t + compressLimitedOutput(const char* aSource, size_t aInputSize, char* aDest, + size_t aMaxOutputSize); + + /** + * If the source stream is malformed, the function will stop decoding + * and return false. + * + * This function never writes outside of provided buffers, and never + * modifies input buffer. + * + * Note: destination buffer must be already allocated, and its size must be a + * minimum of |aOutputSize| bytes. + * + * @param aOutputSize is the output size, therefore the original size + * @return true on success, false on failure + */ + static MFBT_API MOZ_MUST_USE bool + decompress(const char* aSource, char* aDest, size_t aOutputSize); + + /** + * If the source stream is malformed, the function will stop decoding + * and return false. + * + * This function never writes beyond aDest + aMaxOutputSize, and is + * therefore protected against malicious data packets. + * + * Note: Destination buffer must be already allocated. This version is + * slightly slower than the decompress without the aMaxOutputSize. + * + * @param aInputSize is the length of the input compressed data + * @param aMaxOutputSize is the size of the destination buffer (which must be + * already allocated) + * @param aOutputSize the actual number of bytes decoded in the destination + * buffer (necessarily <= aMaxOutputSize) + * @return true on success, false on failure + */ + static MFBT_API MOZ_MUST_USE bool + decompress(const char* aSource, size_t aInputSize, char* aDest, + size_t aMaxOutputSize, size_t* aOutputSize); + + /* + * Provides the maximum size that LZ4 may output in a "worst case" + * scenario (input data not compressible) primarily useful for memory + * allocation of output buffer. + * note : this function is limited by "int" range (2^31-1) + * + * @param aInputSize is the input size. Max supported value is ~1.9GB + * @return maximum output size in a "worst case" scenario + */ + static inline size_t maxCompressedSize(size_t aInputSize) + { + size_t max = (aInputSize + (aInputSize / 255) + 16); + MOZ_ASSERT(max > aInputSize); + return max; + } +}; + +} /* namespace Compression */ +} /* namespace mozilla */ + +#endif /* mozilla_Compression_h_ */ diff --git a/mfbt/DebugOnly.h b/mfbt/DebugOnly.h new file mode 100644 index 000000000..a1a669dba --- /dev/null +++ b/mfbt/DebugOnly.h @@ -0,0 +1,92 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* + * Provides DebugOnly, a type for variables used only in debug builds (i.e. by + * assertions). + */ + +#ifndef mozilla_DebugOnly_h +#define mozilla_DebugOnly_h + +#include "mozilla/Attributes.h" + +namespace mozilla { + +/** + * DebugOnly contains a value of type T, but only in debug builds. In release + * builds, it does not contain a value. This helper is intended to be used with + * MOZ_ASSERT()-style macros, allowing one to write: + * + * DebugOnly<bool> check = func(); + * MOZ_ASSERT(check); + * + * more concisely than declaring |check| conditional on #ifdef DEBUG. + * + * DebugOnly instances can only be coerced to T in debug builds. In release + * builds they don't have a value, so type coercion is not well defined. + * + * NOTE: DebugOnly instances still take up one byte of space, plus padding, even + * in optimized, non-DEBUG builds (see bug 1253094 comment 37 for more info). + * For this reason the class is MOZ_STACK_CLASS to prevent consumers using + * DebugOnly for struct/class members and unwittingly inflating the size of + * their objects in release builds. + */ +template<typename T> +class MOZ_STACK_CLASS DebugOnly +{ +public: +#ifdef DEBUG + T value; + + DebugOnly() { } + MOZ_IMPLICIT DebugOnly(const T& aOther) : value(aOther) { } + DebugOnly(const DebugOnly& aOther) : value(aOther.value) { } + DebugOnly& operator=(const T& aRhs) { + value = aRhs; + return *this; + } + + void operator++(int) { value++; } + void operator--(int) { value--; } + + // Do not define operator+=(), etc. here. These will coerce via the + // implicit cast and built-in operators. Defining explicit methods here + // will create ambiguity the compiler can't deal with. + + T* operator&() { return &value; } + + operator T&() { return value; } + operator const T&() const { return value; } + + T& operator->() { return value; } + const T& operator->() const { return value; } + +#else + DebugOnly() { } + MOZ_IMPLICIT DebugOnly(const T&) { } + DebugOnly(const DebugOnly&) { } + DebugOnly& operator=(const T&) { return *this; } + void operator++(int) { } + void operator--(int) { } + DebugOnly& operator+=(const T&) { return *this; } + DebugOnly& operator-=(const T&) { return *this; } + DebugOnly& operator&=(const T&) { return *this; } + DebugOnly& operator|=(const T&) { return *this; } + DebugOnly& operator^=(const T&) { return *this; } +#endif + + /* + * DebugOnly must always have a destructor or else it will + * generate "unused variable" warnings, exactly what it's intended + * to avoid! + */ + ~DebugOnly() {} +}; + +} // namespace mozilla + +#endif /* mozilla_DebugOnly_h */ diff --git a/mfbt/EndianUtils.h b/mfbt/EndianUtils.h new file mode 100644 index 000000000..008155807 --- /dev/null +++ b/mfbt/EndianUtils.h @@ -0,0 +1,695 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Functions for reading and writing integers in various endiannesses. */ + +/* + * The classes LittleEndian and BigEndian expose static methods for + * reading and writing 16-, 32-, and 64-bit signed and unsigned integers + * in their respective endianness. The naming scheme is: + * + * {Little,Big}Endian::{read,write}{Uint,Int}<bitsize> + * + * For instance, LittleEndian::readInt32 will read a 32-bit signed + * integer from memory in little endian format. Similarly, + * BigEndian::writeUint16 will write a 16-bit unsigned integer to memory + * in big-endian format. + * + * The class NativeEndian exposes methods for conversion of existing + * data to and from the native endianness. These methods are intended + * for cases where data needs to be transferred, serialized, etc. + * swap{To,From}{Little,Big}Endian byteswap a single value if necessary. + * Bulk conversion functions are also provided which optimize the + * no-conversion-needed case: + * + * - copyAndSwap{To,From}{Little,Big}Endian; + * - swap{To,From}{Little,Big}EndianInPlace. + * + * The *From* variants are intended to be used for reading data and the + * *To* variants for writing data. + * + * Methods on NativeEndian work with integer data of any type. + * Floating-point data is not supported. + * + * For clarity in networking code, "Network" may be used as a synonym + * for "Big" in any of the above methods or class names. + * + * As an example, reading a file format header whose fields are stored + * in big-endian format might look like: + * + * class ExampleHeader + * { + * private: + * uint32_t mMagic; + * uint32_t mLength; + * uint32_t mTotalRecords; + * uint64_t mChecksum; + * + * public: + * ExampleHeader(const void* data) + * { + * const uint8_t* ptr = static_cast<const uint8_t*>(data); + * mMagic = BigEndian::readUint32(ptr); ptr += sizeof(uint32_t); + * mLength = BigEndian::readUint32(ptr); ptr += sizeof(uint32_t); + * mTotalRecords = BigEndian::readUint32(ptr); ptr += sizeof(uint32_t); + * mChecksum = BigEndian::readUint64(ptr); + * } + * ... + * }; + */ + +#ifndef mozilla_EndianUtils_h +#define mozilla_EndianUtils_h + +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" +#include "mozilla/Compiler.h" +#include "mozilla/DebugOnly.h" +#include "mozilla/TypeTraits.h" + +#include <stdint.h> +#include <string.h> + +#if defined(_MSC_VER) +# include <stdlib.h> +# pragma intrinsic(_byteswap_ushort) +# pragma intrinsic(_byteswap_ulong) +# pragma intrinsic(_byteswap_uint64) +#endif + +#if defined(_WIN64) +# if defined(_M_X64) || defined(_M_AMD64) || defined(_AMD64_) +# define MOZ_LITTLE_ENDIAN 1 +# else +# error "CPU type is unknown" +# endif +#elif defined(_WIN32) +# if defined(_M_IX86) +# define MOZ_LITTLE_ENDIAN 1 +# elif defined(_M_ARM) +# define MOZ_LITTLE_ENDIAN 1 +# else +# error "CPU type is unknown" +# endif +#elif defined(__APPLE__) || defined(__powerpc__) || defined(__ppc__) +# if __LITTLE_ENDIAN__ +# define MOZ_LITTLE_ENDIAN 1 +# elif __BIG_ENDIAN__ +# define MOZ_BIG_ENDIAN 1 +# endif +#elif defined(__GNUC__) && \ + defined(__BYTE_ORDER__) && \ + defined(__ORDER_LITTLE_ENDIAN__) && \ + defined(__ORDER_BIG_ENDIAN__) + /* + * Some versions of GCC provide architecture-independent macros for + * this. Yes, there are more than two values for __BYTE_ORDER__. + */ +# if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ +# define MOZ_LITTLE_ENDIAN 1 +# elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__ +# define MOZ_BIG_ENDIAN 1 +# else +# error "Can't handle mixed-endian architectures" +# endif +/* + * We can't include useful headers like <endian.h> or <sys/isa_defs.h> + * here because they're not present on all platforms. Instead we have + * this big conditional that ideally will catch all the interesting + * cases. + */ +#elif defined(__sparc) || defined(__sparc__) || \ + defined(_POWER) || defined(__hppa) || \ + defined(_MIPSEB) || defined(__ARMEB__) || \ + defined(__s390__) || defined(__AARCH64EB__) || \ + (defined(__sh__) && defined(__LITTLE_ENDIAN__)) || \ + (defined(__ia64) && defined(__BIG_ENDIAN__)) +# define MOZ_BIG_ENDIAN 1 +#elif defined(__i386) || defined(__i386__) || \ + defined(__x86_64) || defined(__x86_64__) || \ + defined(_MIPSEL) || defined(__ARMEL__) || \ + defined(__alpha__) || defined(__AARCH64EL__) || \ + (defined(__sh__) && defined(__BIG_ENDIAN__)) || \ + (defined(__ia64) && !defined(__BIG_ENDIAN__)) +# define MOZ_LITTLE_ENDIAN 1 +#endif + +#if MOZ_BIG_ENDIAN +# define MOZ_LITTLE_ENDIAN 0 +#elif MOZ_LITTLE_ENDIAN +# define MOZ_BIG_ENDIAN 0 +#else +# error "Cannot determine endianness" +#endif + +#if defined(__clang__) +# if __has_builtin(__builtin_bswap16) +# define MOZ_HAVE_BUILTIN_BYTESWAP16 __builtin_bswap16 +# endif +#elif defined(__GNUC__) +# define MOZ_HAVE_BUILTIN_BYTESWAP16 __builtin_bswap16 +#elif defined(_MSC_VER) +# define MOZ_HAVE_BUILTIN_BYTESWAP16 _byteswap_ushort +#endif + +namespace mozilla { + +namespace detail { + +/* + * We need wrappers here because free functions with default template + * arguments and/or partial specialization of function templates are not + * supported by all the compilers we use. + */ +template<typename T, size_t Size = sizeof(T)> +struct Swapper; + +template<typename T> +struct Swapper<T, 2> +{ + static T swap(T aValue) + { +#if defined(MOZ_HAVE_BUILTIN_BYTESWAP16) + return MOZ_HAVE_BUILTIN_BYTESWAP16(aValue); +#else + return T(((aValue & 0x00ff) << 8) | ((aValue & 0xff00) >> 8)); +#endif + } +}; + +template<typename T> +struct Swapper<T, 4> +{ + static T swap(T aValue) + { +#if defined(__clang__) || defined(__GNUC__) + return T(__builtin_bswap32(aValue)); +#elif defined(_MSC_VER) + return T(_byteswap_ulong(aValue)); +#else + return T(((aValue & 0x000000ffU) << 24) | + ((aValue & 0x0000ff00U) << 8) | + ((aValue & 0x00ff0000U) >> 8) | + ((aValue & 0xff000000U) >> 24)); +#endif + } +}; + +template<typename T> +struct Swapper<T, 8> +{ + static inline T swap(T aValue) + { +#if defined(__clang__) || defined(__GNUC__) + return T(__builtin_bswap64(aValue)); +#elif defined(_MSC_VER) + return T(_byteswap_uint64(aValue)); +#else + return T(((aValue & 0x00000000000000ffULL) << 56) | + ((aValue & 0x000000000000ff00ULL) << 40) | + ((aValue & 0x0000000000ff0000ULL) << 24) | + ((aValue & 0x00000000ff000000ULL) << 8) | + ((aValue & 0x000000ff00000000ULL) >> 8) | + ((aValue & 0x0000ff0000000000ULL) >> 24) | + ((aValue & 0x00ff000000000000ULL) >> 40) | + ((aValue & 0xff00000000000000ULL) >> 56)); +#endif + } +}; + +enum Endianness { Little, Big }; + +#if MOZ_BIG_ENDIAN +# define MOZ_NATIVE_ENDIANNESS detail::Big +#else +# define MOZ_NATIVE_ENDIANNESS detail::Little +#endif + +class EndianUtils +{ + /** + * Assert that the memory regions [aDest, aDest+aCount) and + * [aSrc, aSrc+aCount] do not overlap. aCount is given in bytes. + */ + static void assertNoOverlap(const void* aDest, const void* aSrc, + size_t aCount) + { + DebugOnly<const uint8_t*> byteDestPtr = static_cast<const uint8_t*>(aDest); + DebugOnly<const uint8_t*> byteSrcPtr = static_cast<const uint8_t*>(aSrc); + MOZ_ASSERT((byteDestPtr <= byteSrcPtr && + byteDestPtr + aCount <= byteSrcPtr) || + (byteSrcPtr <= byteDestPtr && + byteSrcPtr + aCount <= byteDestPtr)); + } + + template<typename T> + static void assertAligned(T* aPtr) + { + MOZ_ASSERT((uintptr_t(aPtr) % sizeof(T)) == 0, "Unaligned pointer!"); + } + +protected: + /** + * Return |aValue| converted from SourceEndian encoding to DestEndian + * encoding. + */ + template<Endianness SourceEndian, Endianness DestEndian, typename T> + static inline T maybeSwap(T aValue) + { + if (SourceEndian == DestEndian) { + return aValue; + } + return Swapper<T>::swap(aValue); + } + + /** + * Convert |aCount| elements at |aPtr| from SourceEndian encoding to + * DestEndian encoding. + */ + template<Endianness SourceEndian, Endianness DestEndian, typename T> + static inline void maybeSwapInPlace(T* aPtr, size_t aCount) + { + assertAligned(aPtr); + + if (SourceEndian == DestEndian) { + return; + } + for (size_t i = 0; i < aCount; i++) { + aPtr[i] = Swapper<T>::swap(aPtr[i]); + } + } + + /** + * Write |aCount| elements to the unaligned address |aDest| in DestEndian + * format, using elements found at |aSrc| in SourceEndian format. + */ + template<Endianness SourceEndian, Endianness DestEndian, typename T> + static void copyAndSwapTo(void* aDest, const T* aSrc, size_t aCount) + { + assertNoOverlap(aDest, aSrc, aCount * sizeof(T)); + assertAligned(aSrc); + + if (SourceEndian == DestEndian) { + memcpy(aDest, aSrc, aCount * sizeof(T)); + return; + } + + uint8_t* byteDestPtr = static_cast<uint8_t*>(aDest); + for (size_t i = 0; i < aCount; ++i) { + union + { + T mVal; + uint8_t mBuffer[sizeof(T)]; + } u; + u.mVal = maybeSwap<SourceEndian, DestEndian>(aSrc[i]); + memcpy(byteDestPtr, u.mBuffer, sizeof(T)); + byteDestPtr += sizeof(T); + } + } + + /** + * Write |aCount| elements to |aDest| in DestEndian format, using elements + * found at the unaligned address |aSrc| in SourceEndian format. + */ + template<Endianness SourceEndian, Endianness DestEndian, typename T> + static void copyAndSwapFrom(T* aDest, const void* aSrc, size_t aCount) + { + assertNoOverlap(aDest, aSrc, aCount * sizeof(T)); + assertAligned(aDest); + + if (SourceEndian == DestEndian) { + memcpy(aDest, aSrc, aCount * sizeof(T)); + return; + } + + const uint8_t* byteSrcPtr = static_cast<const uint8_t*>(aSrc); + for (size_t i = 0; i < aCount; ++i) { + union + { + T mVal; + uint8_t mBuffer[sizeof(T)]; + } u; + memcpy(u.mBuffer, byteSrcPtr, sizeof(T)); + aDest[i] = maybeSwap<SourceEndian, DestEndian>(u.mVal); + byteSrcPtr += sizeof(T); + } + } +}; + +template<Endianness ThisEndian> +class Endian : private EndianUtils +{ +protected: + /** Read a uint16_t in ThisEndian endianness from |aPtr| and return it. */ + static MOZ_MUST_USE uint16_t readUint16(const void* aPtr) + { + return read<uint16_t>(aPtr); + } + + /** Read a uint32_t in ThisEndian endianness from |aPtr| and return it. */ + static MOZ_MUST_USE uint32_t readUint32(const void* aPtr) + { + return read<uint32_t>(aPtr); + } + + /** Read a uint64_t in ThisEndian endianness from |aPtr| and return it. */ + static MOZ_MUST_USE uint64_t readUint64(const void* aPtr) + { + return read<uint64_t>(aPtr); + } + + /** Read an int16_t in ThisEndian endianness from |aPtr| and return it. */ + static MOZ_MUST_USE int16_t readInt16(const void* aPtr) + { + return read<int16_t>(aPtr); + } + + /** Read an int32_t in ThisEndian endianness from |aPtr| and return it. */ + static MOZ_MUST_USE int32_t readInt32(const void* aPtr) + { + return read<uint32_t>(aPtr); + } + + /** Read an int64_t in ThisEndian endianness from |aPtr| and return it. */ + static MOZ_MUST_USE int64_t readInt64(const void* aPtr) + { + return read<int64_t>(aPtr); + } + + /** Write |aValue| to |aPtr| using ThisEndian endianness. */ + static void writeUint16(void* aPtr, uint16_t aValue) + { + write(aPtr, aValue); + } + + /** Write |aValue| to |aPtr| using ThisEndian endianness. */ + static void writeUint32(void* aPtr, uint32_t aValue) + { + write(aPtr, aValue); + } + + /** Write |aValue| to |aPtr| using ThisEndian endianness. */ + static void writeUint64(void* aPtr, uint64_t aValue) + { + write(aPtr, aValue); + } + + /** Write |aValue| to |aPtr| using ThisEndian endianness. */ + static void writeInt16(void* aPtr, int16_t aValue) + { + write(aPtr, aValue); + } + + /** Write |aValue| to |aPtr| using ThisEndian endianness. */ + static void writeInt32(void* aPtr, int32_t aValue) + { + write(aPtr, aValue); + } + + /** Write |aValue| to |aPtr| using ThisEndian endianness. */ + static void writeInt64(void* aPtr, int64_t aValue) + { + write(aPtr, aValue); + } + + /* + * Converts a value of type T to little-endian format. + * + * This function is intended for cases where you have data in your + * native-endian format and you need it to appear in little-endian + * format for transmission. + */ + template<typename T> + MOZ_MUST_USE static T swapToLittleEndian(T aValue) + { + return maybeSwap<ThisEndian, Little>(aValue); + } + + /* + * Copies |aCount| values of type T starting at |aSrc| to |aDest|, converting + * them to little-endian format if ThisEndian is Big. + * As with memcpy, |aDest| and |aSrc| must not overlap. + */ + template<typename T> + static void copyAndSwapToLittleEndian(void* aDest, const T* aSrc, + size_t aCount) + { + copyAndSwapTo<ThisEndian, Little>(aDest, aSrc, aCount); + } + + /* + * Likewise, but converts values in place. + */ + template<typename T> + static void swapToLittleEndianInPlace(T* aPtr, size_t aCount) + { + maybeSwapInPlace<ThisEndian, Little>(aPtr, aCount); + } + + /* + * Converts a value of type T to big-endian format. + */ + template<typename T> + MOZ_MUST_USE static T swapToBigEndian(T aValue) + { + return maybeSwap<ThisEndian, Big>(aValue); + } + + /* + * Copies |aCount| values of type T starting at |aSrc| to |aDest|, converting + * them to big-endian format if ThisEndian is Little. + * As with memcpy, |aDest| and |aSrc| must not overlap. + */ + template<typename T> + static void copyAndSwapToBigEndian(void* aDest, const T* aSrc, + size_t aCount) + { + copyAndSwapTo<ThisEndian, Big>(aDest, aSrc, aCount); + } + + /* + * Likewise, but converts values in place. + */ + template<typename T> + static void swapToBigEndianInPlace(T* aPtr, size_t aCount) + { + maybeSwapInPlace<ThisEndian, Big>(aPtr, aCount); + } + + /* + * Synonyms for the big-endian functions, for better readability + * in network code. + */ + + template<typename T> + MOZ_MUST_USE static T swapToNetworkOrder(T aValue) + { + return swapToBigEndian(aValue); + } + + template<typename T> + static void + copyAndSwapToNetworkOrder(void* aDest, const T* aSrc, size_t aCount) + { + copyAndSwapToBigEndian(aDest, aSrc, aCount); + } + + template<typename T> + static void + swapToNetworkOrderInPlace(T* aPtr, size_t aCount) + { + swapToBigEndianInPlace(aPtr, aCount); + } + + /* + * Converts a value of type T from little-endian format. + */ + template<typename T> + MOZ_MUST_USE static T swapFromLittleEndian(T aValue) + { + return maybeSwap<Little, ThisEndian>(aValue); + } + + /* + * Copies |aCount| values of type T starting at |aSrc| to |aDest|, converting + * them to little-endian format if ThisEndian is Big. + * As with memcpy, |aDest| and |aSrc| must not overlap. + */ + template<typename T> + static void copyAndSwapFromLittleEndian(T* aDest, const void* aSrc, + size_t aCount) + { + copyAndSwapFrom<Little, ThisEndian>(aDest, aSrc, aCount); + } + + /* + * Likewise, but converts values in place. + */ + template<typename T> + static void swapFromLittleEndianInPlace(T* aPtr, size_t aCount) + { + maybeSwapInPlace<Little, ThisEndian>(aPtr, aCount); + } + + /* + * Converts a value of type T from big-endian format. + */ + template<typename T> + MOZ_MUST_USE static T swapFromBigEndian(T aValue) + { + return maybeSwap<Big, ThisEndian>(aValue); + } + + /* + * Copies |aCount| values of type T starting at |aSrc| to |aDest|, converting + * them to big-endian format if ThisEndian is Little. + * As with memcpy, |aDest| and |aSrc| must not overlap. + */ + template<typename T> + static void copyAndSwapFromBigEndian(T* aDest, const void* aSrc, + size_t aCount) + { + copyAndSwapFrom<Big, ThisEndian>(aDest, aSrc, aCount); + } + + /* + * Likewise, but converts values in place. + */ + template<typename T> + static void swapFromBigEndianInPlace(T* aPtr, size_t aCount) + { + maybeSwapInPlace<Big, ThisEndian>(aPtr, aCount); + } + + /* + * Synonyms for the big-endian functions, for better readability + * in network code. + */ + template<typename T> + MOZ_MUST_USE static T swapFromNetworkOrder(T aValue) + { + return swapFromBigEndian(aValue); + } + + template<typename T> + static void copyAndSwapFromNetworkOrder(T* aDest, const void* aSrc, + size_t aCount) + { + copyAndSwapFromBigEndian(aDest, aSrc, aCount); + } + + template<typename T> + static void swapFromNetworkOrderInPlace(T* aPtr, size_t aCount) + { + swapFromBigEndianInPlace(aPtr, aCount); + } + +private: + /** + * Read a value of type T, encoded in endianness ThisEndian from |aPtr|. + * Return that value encoded in native endianness. + */ + template<typename T> + static T read(const void* aPtr) + { + union + { + T mVal; + uint8_t mBuffer[sizeof(T)]; + } u; + memcpy(u.mBuffer, aPtr, sizeof(T)); + return maybeSwap<ThisEndian, MOZ_NATIVE_ENDIANNESS>(u.mVal); + } + + /** + * Write a value of type T, in native endianness, to |aPtr|, in ThisEndian + * endianness. + */ + template<typename T> + static void write(void* aPtr, T aValue) + { + T tmp = maybeSwap<MOZ_NATIVE_ENDIANNESS, ThisEndian>(aValue); + memcpy(aPtr, &tmp, sizeof(T)); + } + + Endian() = delete; + Endian(const Endian& aTther) = delete; + void operator=(const Endian& aOther) = delete; +}; + +template<Endianness ThisEndian> +class EndianReadWrite : public Endian<ThisEndian> +{ +private: + typedef Endian<ThisEndian> super; + +public: + using super::readUint16; + using super::readUint32; + using super::readUint64; + using super::readInt16; + using super::readInt32; + using super::readInt64; + using super::writeUint16; + using super::writeUint32; + using super::writeUint64; + using super::writeInt16; + using super::writeInt32; + using super::writeInt64; +}; + +} /* namespace detail */ + +class LittleEndian final : public detail::EndianReadWrite<detail::Little> +{}; + +class BigEndian final : public detail::EndianReadWrite<detail::Big> +{}; + +typedef BigEndian NetworkEndian; + +class NativeEndian final : public detail::Endian<MOZ_NATIVE_ENDIANNESS> +{ +private: + typedef detail::Endian<MOZ_NATIVE_ENDIANNESS> super; + +public: + /* + * These functions are intended for cases where you have data in your + * native-endian format and you need the data to appear in the appropriate + * endianness for transmission, serialization, etc. + */ + using super::swapToLittleEndian; + using super::copyAndSwapToLittleEndian; + using super::swapToLittleEndianInPlace; + using super::swapToBigEndian; + using super::copyAndSwapToBigEndian; + using super::swapToBigEndianInPlace; + using super::swapToNetworkOrder; + using super::copyAndSwapToNetworkOrder; + using super::swapToNetworkOrderInPlace; + + /* + * These functions are intended for cases where you have data in the + * given endianness (e.g. reading from disk or a file-format) and you + * need the data to appear in native-endian format for processing. + */ + using super::swapFromLittleEndian; + using super::copyAndSwapFromLittleEndian; + using super::swapFromLittleEndianInPlace; + using super::swapFromBigEndian; + using super::copyAndSwapFromBigEndian; + using super::swapFromBigEndianInPlace; + using super::swapFromNetworkOrder; + using super::copyAndSwapFromNetworkOrder; + using super::swapFromNetworkOrderInPlace; +}; + +#undef MOZ_NATIVE_ENDIANNESS + +} /* namespace mozilla */ + +#endif /* mozilla_EndianUtils_h */ diff --git a/mfbt/EnumSet.h b/mfbt/EnumSet.h new file mode 100644 index 000000000..5282ab30c --- /dev/null +++ b/mfbt/EnumSet.h @@ -0,0 +1,344 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* A set abstraction for enumeration values. */ + +#ifndef mozilla_EnumSet_h +#define mozilla_EnumSet_h + +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" + +#include <initializer_list> + +#include <stdint.h> + +namespace mozilla { + +/** + * EnumSet<T> is a set of values defined by an enumeration. It is implemented + * using a 32 bit mask for each value so it will only work for enums with an int + * representation less than 32. It works both for enum and enum class types. + */ +template<typename T> +class EnumSet +{ +public: + EnumSet() + : mBitField(0) + { + initVersion(); + } + + MOZ_IMPLICIT EnumSet(T aEnum) + : mBitField(bitFor(aEnum)) + { } + + EnumSet(T aEnum1, T aEnum2) + : mBitField(bitFor(aEnum1) | + bitFor(aEnum2)) + { + initVersion(); + } + + EnumSet(T aEnum1, T aEnum2, T aEnum3) + : mBitField(bitFor(aEnum1) | + bitFor(aEnum2) | + bitFor(aEnum3)) + { + initVersion(); + } + + EnumSet(T aEnum1, T aEnum2, T aEnum3, T aEnum4) + : mBitField(bitFor(aEnum1) | + bitFor(aEnum2) | + bitFor(aEnum3) | + bitFor(aEnum4)) + { + initVersion(); + } + + MOZ_IMPLICIT EnumSet(std::initializer_list<T> list) + : mBitField(0) + { + for (auto value : list) { + (*this) += value; + } + initVersion(); + } + + EnumSet(const EnumSet& aEnumSet) + : mBitField(aEnumSet.mBitField) + { + initVersion(); + } + + /** + * Add an element + */ + void operator+=(T aEnum) + { + incVersion(); + mBitField |= bitFor(aEnum); + } + + /** + * Add an element + */ + EnumSet<T> operator+(T aEnum) const + { + EnumSet<T> result(*this); + result += aEnum; + return result; + } + + /** + * Union + */ + void operator+=(const EnumSet<T> aEnumSet) + { + incVersion(); + mBitField |= aEnumSet.mBitField; + } + + /** + * Union + */ + EnumSet<T> operator+(const EnumSet<T> aEnumSet) const + { + EnumSet<T> result(*this); + result += aEnumSet; + return result; + } + + /** + * Remove an element + */ + void operator-=(T aEnum) + { + incVersion(); + mBitField &= ~(bitFor(aEnum)); + } + + /** + * Remove an element + */ + EnumSet<T> operator-(T aEnum) const + { + EnumSet<T> result(*this); + result -= aEnum; + return result; + } + + /** + * Remove a set of elements + */ + void operator-=(const EnumSet<T> aEnumSet) + { + incVersion(); + mBitField &= ~(aEnumSet.mBitField); + } + + /** + * Remove a set of elements + */ + EnumSet<T> operator-(const EnumSet<T> aEnumSet) const + { + EnumSet<T> result(*this); + result -= aEnumSet; + return result; + } + + /** + * Clear + */ + void clear() + { + incVersion(); + mBitField = 0; + } + + /** + * Intersection + */ + void operator&=(const EnumSet<T> aEnumSet) + { + incVersion(); + mBitField &= aEnumSet.mBitField; + } + + /** + * Intersection + */ + EnumSet<T> operator&(const EnumSet<T> aEnumSet) const + { + EnumSet<T> result(*this); + result &= aEnumSet; + return result; + } + + /** + * Equality + */ + bool operator==(const EnumSet<T> aEnumSet) const + { + return mBitField == aEnumSet.mBitField; + } + + /** + * Test is an element is contained in the set. + */ + bool contains(T aEnum) const + { + return mBitField & bitFor(aEnum); + } + + /** + * Return the number of elements in the set. + */ + uint8_t size() const + { + uint8_t count = 0; + for (uint32_t bitField = mBitField; bitField; bitField >>= 1) { + if (bitField & 1) { + count++; + } + } + return count; + } + + bool isEmpty() const + { + return mBitField == 0; + } + + uint32_t serialize() const + { + return mBitField; + } + + void deserialize(uint32_t aValue) + { + incVersion(); + mBitField = aValue; + } + + class ConstIterator + { + const EnumSet<T>* mSet; + uint32_t mPos; +#ifdef DEBUG + uint64_t mVersion; +#endif + + void checkVersion() { + // Check that the set has not been modified while being iterated. + MOZ_ASSERT_IF(mSet, mSet->mVersion == mVersion); + } + + public: + ConstIterator(const EnumSet<T>& aSet, uint32_t aPos) + : mSet(&aSet), mPos(aPos) + { +#ifdef DEBUG + mVersion = mSet->mVersion; +#endif + MOZ_ASSERT(aPos <= kMaxBits); + if (aPos != kMaxBits && !mSet->contains(T(mPos))) + ++*this; + } + + ConstIterator(const ConstIterator& aOther) + : mSet(aOther.mSet), mPos(aOther.mPos) + { +#ifdef DEBUG + mVersion = aOther.mVersion; + checkVersion(); +#endif + } + + ConstIterator(ConstIterator&& aOther) + : mSet(aOther.mSet), mPos(aOther.mPos) + { +#ifdef DEBUG + mVersion = aOther.mVersion; + checkVersion(); +#endif + aOther.mSet = nullptr; + } + + ~ConstIterator() { + checkVersion(); + } + + bool operator==(const ConstIterator& other) { + MOZ_ASSERT(mSet == other.mSet); + checkVersion(); + return mPos == other.mPos; + } + + bool operator!=(const ConstIterator& other) { + return !(*this == other); + } + + T operator*() { + MOZ_ASSERT(mSet); + MOZ_ASSERT(mPos < kMaxBits); + MOZ_ASSERT(mSet->contains(T(mPos))); + checkVersion(); + return T(mPos); + } + + ConstIterator& operator++() { + MOZ_ASSERT(mSet); + MOZ_ASSERT(mPos < kMaxBits); + checkVersion(); + do { + mPos++; + } while (mPos < kMaxBits && !mSet->contains(T(mPos))); + return *this; + } + }; + + ConstIterator begin() const { + return ConstIterator(*this, 0); + } + + ConstIterator end() const { + return ConstIterator(*this, kMaxBits); + } + +private: + static uint32_t bitFor(T aEnum) + { + uint32_t bitNumber = (uint32_t)aEnum; + MOZ_ASSERT(bitNumber < kMaxBits); + return 1U << bitNumber; + } + + void initVersion() { +#ifdef DEBUG + mVersion = 0; +#endif + } + + void incVersion() { +#ifdef DEBUG + mVersion++; +#endif + } + + static const size_t kMaxBits = 32; + uint32_t mBitField; + +#ifdef DEBUG + uint64_t mVersion; +#endif +}; + +} // namespace mozilla + +#endif /* mozilla_EnumSet_h_*/ diff --git a/mfbt/EnumTypeTraits.h b/mfbt/EnumTypeTraits.h new file mode 100644 index 000000000..223eaf8c0 --- /dev/null +++ b/mfbt/EnumTypeTraits.h @@ -0,0 +1,70 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Type traits for enums. */ + +#ifndef mozilla_EnumTypeTraits_h +#define mozilla_EnumTypeTraits_h + +#include <type_traits> + +namespace mozilla { + +namespace detail { + +template<size_t EnumSize, bool EnumSigned, size_t StorageSize, bool StorageSigned> +struct EnumFitsWithinHelper; + +// Signed enum, signed storage. +template<size_t EnumSize, size_t StorageSize> +struct EnumFitsWithinHelper<EnumSize, true, StorageSize, true> + : public std::integral_constant<bool, (EnumSize <= StorageSize)> +{}; + +// Signed enum, unsigned storage. +template<size_t EnumSize, size_t StorageSize> +struct EnumFitsWithinHelper<EnumSize, true, StorageSize, false> + : public std::integral_constant<bool, false> +{}; + +// Unsigned enum, signed storage. +template<size_t EnumSize, size_t StorageSize> +struct EnumFitsWithinHelper<EnumSize, false, StorageSize, true> + : public std::integral_constant<bool, (EnumSize * 2 <= StorageSize)> +{}; + +// Unsigned enum, unsigned storage. +template<size_t EnumSize, size_t StorageSize> +struct EnumFitsWithinHelper<EnumSize, false, StorageSize, false> + : public std::integral_constant<bool, (EnumSize <= StorageSize)> +{}; + +} // namespace detail + +/* + * Type trait that determines whether the enum type T can fit within the + * integral type Storage without data loss. This trait should be used with + * caution with an enum type whose underlying type has not been explicitly + * specified: for such enums, the C++ implementation is free to choose a type + * no smaller than int whose range encompasses all possible values of the enum. + * So for an enum with only small non-negative values, the underlying type may + * be either int or unsigned int, depending on the whims of the implementation. + */ +template<typename T, typename Storage> +struct EnumTypeFitsWithin + : public detail::EnumFitsWithinHelper< + sizeof(T), + std::is_signed<typename std::underlying_type<T>::type>::value, + sizeof(Storage), + std::is_signed<Storage>::value + > +{ + static_assert(std::is_enum<T>::value, "must provide an enum type"); + static_assert(std::is_integral<Storage>::value, "must provide an integral type"); +}; + +} // namespace mozilla + +#endif /* mozilla_EnumTypeTraits_h */ diff --git a/mfbt/EnumeratedArray.h b/mfbt/EnumeratedArray.h new file mode 100644 index 000000000..9e74b7724 --- /dev/null +++ b/mfbt/EnumeratedArray.h @@ -0,0 +1,110 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* EnumeratedArray is like Array, but indexed by a typed enum. */ + +#ifndef mozilla_EnumeratedArray_h +#define mozilla_EnumeratedArray_h + +#include "mozilla/Array.h" +#include "mozilla/Move.h" + +namespace mozilla { + +/** + * EnumeratedArray is a fixed-size array container for use when an + * array is indexed by a specific enum class. + * + * This provides type safety by guarding at compile time against accidentally + * indexing such arrays with unrelated values. This also removes the need + * for manual casting when using a typed enum value to index arrays. + * + * Aside from the typing of indices, EnumeratedArray is similar to Array. + * + * Example: + * + * enum class AnimalSpecies { + * Cow, + * Sheep, + * Count + * }; + * + * EnumeratedArray<AnimalSpecies, AnimalSpecies::Count, int> headCount; + * + * headCount[AnimalSpecies::Cow] = 17; + * headCount[AnimalSpecies::Sheep] = 30; + * + */ +template<typename IndexType, + IndexType SizeAsEnumValue, + typename ValueType> +class EnumeratedArray +{ +public: + static const size_t kSize = size_t(SizeAsEnumValue); + +private: + typedef Array<ValueType, kSize> ArrayType; + + ArrayType mArray; + +public: + EnumeratedArray() {} + + template <typename... Args> + MOZ_IMPLICIT EnumeratedArray(Args&&... aArgs) + : mArray{mozilla::Forward<Args>(aArgs)...} + {} + + explicit EnumeratedArray(const EnumeratedArray& aOther) + { + for (size_t i = 0; i < kSize; i++) { + mArray[i] = aOther.mArray[i]; + } + } + + EnumeratedArray(EnumeratedArray&& aOther) + { + for (size_t i = 0; i < kSize; i++) { + mArray[i] = Move(aOther.mArray[i]); + } + } + + ValueType& operator[](IndexType aIndex) + { + return mArray[size_t(aIndex)]; + } + + const ValueType& operator[](IndexType aIndex) const + { + return mArray[size_t(aIndex)]; + } + + typedef typename ArrayType::iterator iterator; + typedef typename ArrayType::const_iterator const_iterator; + typedef typename ArrayType::reverse_iterator reverse_iterator; + typedef typename ArrayType::const_reverse_iterator const_reverse_iterator; + + // Methods for range-based for loops. + iterator begin() { return mArray.begin(); } + const_iterator begin() const { return mArray.begin(); } + const_iterator cbegin() const { return mArray.cbegin(); } + iterator end() { return mArray.end(); } + const_iterator end() const { return mArray.end(); } + const_iterator cend() const { return mArray.cend(); } + + // Methods for reverse iterating. + reverse_iterator rbegin() { return mArray.rbegin(); } + const_reverse_iterator rbegin() const { return mArray.rbegin(); } + const_reverse_iterator crbegin() const { return mArray.crbegin(); } + reverse_iterator rend() { return mArray.rend(); } + const_reverse_iterator rend() const { return mArray.rend(); } + const_reverse_iterator crend() const { return mArray.crend(); } +}; + +} // namespace mozilla + +#endif // mozilla_EnumeratedArray_h diff --git a/mfbt/EnumeratedRange.h b/mfbt/EnumeratedRange.h new file mode 100644 index 000000000..b158f8a3a --- /dev/null +++ b/mfbt/EnumeratedRange.h @@ -0,0 +1,201 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Iterator over contiguous enum values */ + +/* + * Implements generator functions that create a range to iterate over the values + * of a scoped or unscoped enum. Unlike IntegerRange, which can only function on + * the underlying integral type, the elements of the generated sequence will + * have the type of the enum in question. + * + * Note that the enum values should be contiguous in the iterated range; + * unfortunately there exists no way for EnumeratedRange to enforce this + * either dynamically or at compile time. + */ + +#ifndef mozilla_EnumeratedRange_h +#define mozilla_EnumeratedRange_h + +#include <type_traits> + +#include "mozilla/ReverseIterator.h" + +namespace mozilla { + +namespace detail { + +template<typename EnumTypeT> +class EnumeratedIterator +{ +public: + typedef typename std::underlying_type<EnumTypeT>::type IntTypeT; + + template<typename EnumType> + explicit EnumeratedIterator(EnumType aCurrent) + : mCurrent(aCurrent) { } + + template<typename EnumType> + explicit EnumeratedIterator(const EnumeratedIterator<EnumType>& aOther) + : mCurrent(aOther.mCurrent) { } + + EnumTypeT operator*() const { return mCurrent; } + + /* Increment and decrement operators */ + + EnumeratedIterator& operator++() + { + mCurrent = EnumTypeT(IntTypeT(mCurrent) + IntTypeT(1)); + return *this; + } + EnumeratedIterator& operator--() + { + mCurrent = EnumTypeT(IntTypeT(mCurrent) - IntTypeT(1)); + return *this; + } + EnumeratedIterator operator++(int) + { + auto ret = *this; + mCurrent = EnumTypeT(IntTypeT(mCurrent) + IntTypeT(1)); + return ret; + } + EnumeratedIterator operator--(int) + { + auto ret = *this; + mCurrent = EnumTypeT(IntTypeT(mCurrent) - IntTypeT(1)); + return ret; + } + + /* Comparison operators */ + + template<typename EnumType> + friend bool operator==(const EnumeratedIterator<EnumType>& aIter1, + const EnumeratedIterator<EnumType>& aIter2); + template<typename EnumType> + friend bool operator!=(const EnumeratedIterator<EnumType>& aIter1, + const EnumeratedIterator<EnumType>& aIter2); + template<typename EnumType> + friend bool operator<(const EnumeratedIterator<EnumType>& aIter1, + const EnumeratedIterator<EnumType>& aIter2); + template<typename EnumType> + friend bool operator<=(const EnumeratedIterator<EnumType>& aIter1, + const EnumeratedIterator<EnumType>& aIter2); + template<typename EnumType> + friend bool operator>(const EnumeratedIterator<EnumType>& aIter1, + const EnumeratedIterator<EnumType>& aIter2); + template<typename EnumType> + friend bool operator>=(const EnumeratedIterator<EnumType>& aIter1, + const EnumeratedIterator<EnumType>& aIter2); + +private: + EnumTypeT mCurrent; +}; + +template<typename EnumType> +bool operator==(const EnumeratedIterator<EnumType>& aIter1, + const EnumeratedIterator<EnumType>& aIter2) +{ + return aIter1.mCurrent == aIter2.mCurrent; +} + +template<typename EnumType> +bool operator!=(const EnumeratedIterator<EnumType>& aIter1, + const EnumeratedIterator<EnumType>& aIter2) +{ + return aIter1.mCurrent != aIter2.mCurrent; +} + +template<typename EnumType> +bool operator<(const EnumeratedIterator<EnumType>& aIter1, + const EnumeratedIterator<EnumType>& aIter2) +{ + return aIter1.mCurrent < aIter2.mCurrent; +} + +template<typename EnumType> +bool operator<=(const EnumeratedIterator<EnumType>& aIter1, + const EnumeratedIterator<EnumType>& aIter2) +{ + return aIter1.mCurrent <= aIter2.mCurrent; +} + +template<typename EnumType> +bool operator>(const EnumeratedIterator<EnumType>& aIter1, + const EnumeratedIterator<EnumType>& aIter2) +{ + return aIter1.mCurrent > aIter2.mCurrent; +} + +template<typename EnumType> +bool operator>=(const EnumeratedIterator<EnumType>& aIter1, + const EnumeratedIterator<EnumType>& aIter2) +{ + return aIter1.mCurrent >= aIter2.mCurrent; +} + +template<typename EnumTypeT> +class EnumeratedRange +{ +public: + typedef EnumeratedIterator<EnumTypeT> iterator; + typedef EnumeratedIterator<EnumTypeT> const_iterator; + typedef ReverseIterator<iterator> reverse_iterator; + typedef ReverseIterator<const_iterator> const_reverse_iterator; + + template<typename EnumType> + EnumeratedRange(EnumType aBegin, EnumType aEnd) + : mBegin(aBegin), mEnd(aEnd) { } + + iterator begin() const { return iterator(mBegin); } + const_iterator cbegin() const { return begin(); } + iterator end() const { return iterator(mEnd); } + const_iterator cend() const { return end(); } + reverse_iterator rbegin() const { return reverse_iterator(mEnd); } + const_reverse_iterator crbegin() const { return rbegin(); } + reverse_iterator rend() const { return reverse_iterator(mBegin); } + const_reverse_iterator crend() const { return rend(); } + +private: + EnumTypeT mBegin; + EnumTypeT mEnd; +}; + +} // namespace detail + +#ifdef __GNUC__ +// Enums can have an unsigned underlying type, which makes some of the +// comparisons below always true or always false. Temporarily disable +// -Wtype-limits to avoid breaking -Werror builds. +# pragma GCC diagnostic push +# pragma GCC diagnostic ignored "-Wtype-limits" +#endif + +// Create a range to iterate from aBegin to aEnd, exclusive. +template<typename EnumType> +inline detail::EnumeratedRange<EnumType> +MakeEnumeratedRange(EnumType aBegin, EnumType aEnd) +{ + MOZ_ASSERT(aBegin <= aEnd, "Cannot generate invalid, unbounded range!"); + return detail::EnumeratedRange<EnumType>(aBegin, aEnd); +} + +// Create a range to iterate from EnumType(0) to aEnd, exclusive. EnumType(0) +// should exist, but note that there is no way for us to ensure that it does! +template<typename EnumType> +inline detail::EnumeratedRange<EnumType> +MakeEnumeratedRange(EnumType aEnd) +{ + return MakeEnumeratedRange(EnumType(0), aEnd); +} + +#ifdef __GNUC__ +# pragma GCC diagnostic pop +#endif + +} // namespace mozilla + +#endif // mozilla_EnumeratedRange_h + diff --git a/mfbt/FastBernoulliTrial.h b/mfbt/FastBernoulliTrial.h new file mode 100644 index 000000000..7e38b70ab --- /dev/null +++ b/mfbt/FastBernoulliTrial.h @@ -0,0 +1,379 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef mozilla_FastBernoulliTrial_h +#define mozilla_FastBernoulliTrial_h + +#include "mozilla/Assertions.h" +#include "mozilla/XorShift128PlusRNG.h" + +#include <cmath> +#include <stdint.h> + +namespace mozilla { + +/** + * class FastBernoulliTrial: Efficient sampling with uniform probability + * + * When gathering statistics about a program's behavior, we may be observing + * events that occur very frequently (e.g., function calls or memory + * allocations) and we may be gathering information that is somewhat expensive + * to produce (e.g., call stacks). Sampling all the events could have a + * significant impact on the program's performance. + * + * Why not just sample every N'th event? This technique is called "systematic + * sampling"; it's simple and efficient, and it's fine if we imagine a + * patternless stream of events. But what if we're sampling allocations, and the + * program happens to have a loop where each iteration does exactly N + * allocations? You would end up sampling the same allocation every time through + * the loop; the entire rest of the loop becomes invisible to your measurements! + * More generally, if each iteration does M allocations, and M and N have any + * common divisor at all, most allocation sites will never be sampled. If + * they're both even, say, the odd-numbered allocations disappear from your + * results. + * + * Ideally, we'd like each event to have some probability P of being sampled, + * independent of its neighbors and of its position in the sequence. This is + * called "Bernoulli sampling", and it doesn't suffer from any of the problems + * mentioned above. + * + * One disadvantage of Bernoulli sampling is that you can't be sure exactly how + * many samples you'll get: technically, it's possible that you might sample + * none of them, or all of them. But if the number of events N is large, these + * aren't likely outcomes; you can generally expect somewhere around P * N + * events to be sampled. + * + * The other disadvantage of Bernoulli sampling is that you have to generate a + * random number for every event, which can be slow. + * + * [significant pause] + * + * BUT NOT WITH THIS CLASS! FastBernoulliTrial lets you do true Bernoulli + * sampling, while generating a fresh random number only when we do decide to + * sample an event, not on every trial. When it decides not to sample, a call to + * |FastBernoulliTrial::trial| is nothing but decrementing a counter and + * comparing it to zero. So the lower your sampling probability is, the less + * overhead FastBernoulliTrial imposes. + * + * Probabilities of 0 and 1 are handled efficiently. (In neither case need we + * ever generate a random number at all.) + * + * The essential API: + * + * - FastBernoulliTrial(double P) + * Construct an instance that selects events with probability P. + * + * - FastBernoulliTrial::trial() + * Return true with probability P. Call this each time an event occurs, to + * decide whether to sample it or not. + * + * - FastBernoulliTrial::trial(size_t n) + * Equivalent to calling trial() |n| times, and returning true if any of those + * calls do. However, like trial, this runs in fast constant time. + * + * What is this good for? In some applications, some events are "bigger" than + * others. For example, large allocations are more significant than small + * allocations. Perhaps we'd like to imagine that we're drawing allocations + * from a stream of bytes, and performing a separate Bernoulli trial on every + * byte from the stream. We can accomplish this by calling |t.trial(S)| for + * the number of bytes S, and sampling the event if that returns true. + * + * Of course, this style of sampling needs to be paired with analysis and + * presentation that makes the size of the event apparent, lest trials with + * large values for |n| appear to be indistinguishable from those with small + * values for |n|. + */ +class FastBernoulliTrial { + /* + * This comment should just read, "Generate skip counts with a geometric + * distribution", and leave everyone to go look that up and see why it's the + * right thing to do, if they don't know already. + * + * BUT IF YOU'RE CURIOUS, COMMENTS ARE FREE... + * + * Instead of generating a fresh random number for every trial, we can + * randomly generate a count of how many times we should return false before + * the next time we return true. We call this a "skip count". Once we've + * returned true, we generate a fresh skip count, and begin counting down + * again. + * + * Here's an awesome fact: by exercising a little care in the way we generate + * skip counts, we can produce results indistinguishable from those we would + * get "rolling the dice" afresh for every trial. + * + * In short, skip counts in Bernoulli trials of probability P obey a geometric + * distribution. If a random variable X is uniformly distributed from [0..1), + * then std::floor(std::log(X) / std::log(1-P)) has the appropriate geometric + * distribution for the skip counts. + * + * Why that formula? + * + * Suppose we're to return |true| with some probability P, say, 0.3. Spread + * all possible futures along a line segment of length 1. In portion P of + * those cases, we'll return true on the next call to |trial|; the skip count + * is 0. For the remaining portion 1-P of cases, the skip count is 1 or more. + * + * skip: 0 1 or more + * |------------------^-----------------------------------------| + * portion: 0.3 0.7 + * P 1-P + * + * But the "1 or more" section of the line is subdivided the same way: *within + * that section*, in portion P the second call to |trial()| returns true, and in + * portion 1-P it returns false a second time; the skip count is two or more. + * So we return true on the second call in proportion 0.7 * 0.3, and skip at + * least the first two in proportion 0.7 * 0.7. + * + * skip: 0 1 2 or more + * |------------------^------------^----------------------------| + * portion: 0.3 0.7 * 0.3 0.7 * 0.7 + * P (1-P)*P (1-P)^2 + * + * We can continue to subdivide: + * + * skip >= 0: |------------------------------------------------- (1-P)^0 --| + * skip >= 1: | ------------------------------- (1-P)^1 --| + * skip >= 2: | ------------------ (1-P)^2 --| + * skip >= 3: | ^ ---------- (1-P)^3 --| + * skip >= 4: | . --- (1-P)^4 --| + * . + * ^X, see below + * + * In other words, the likelihood of the next n calls to |trial| returning + * false is (1-P)^n. The longer a run we require, the more the likelihood + * drops. Further calls may return false too, but this is the probability + * we'll skip at least n. + * + * This is interesting, because we can pick a point along this line segment + * and see which skip count's range it falls within; the point X above, for + * example, is within the ">= 2" range, but not within the ">= 3" range, so it + * designates a skip count of 2. So if we pick points on the line at random + * and use the skip counts they fall under, that will be indistinguishable + * from generating a fresh random number between 0 and 1 for each trial and + * comparing it to P. + * + * So to find the skip count for a point X, we must ask: To what whole power + * must we raise 1-P such that we include X, but the next power would exclude + * it? This is exactly std::floor(std::log(X) / std::log(1-P)). + * + * Our algorithm is then, simply: When constructed, compute an initial skip + * count. Return false from |trial| that many times, and then compute a new skip + * count. + * + * For a call to |trial(n)|, if the skip count is greater than n, return false + * and subtract n from the skip count. If the skip count is less than n, + * return true and compute a new skip count. Since each trial is independent, + * it doesn't matter by how much n overshoots the skip count; we can actually + * compute a new skip count at *any* time without affecting the distribution. + * This is really beautiful. + */ + public: + /** + * Construct a fast Bernoulli trial generator. Calls to |trial()| return true + * with probability |aProbability|. Use |aState0| and |aState1| to seed the + * random number generator; both may not be zero. + */ + FastBernoulliTrial(double aProbability, uint64_t aState0, uint64_t aState1) + : mProbability(0) + , mInvLogNotProbability(0) + , mGenerator(aState0, aState1) + , mSkipCount(0) + { + setProbability(aProbability); + } + + /** + * Return true with probability |mProbability|. Call this each time an event + * occurs, to decide whether to sample it or not. The lower |mProbability| is, + * the faster this function runs. + */ + bool trial() { + if (mSkipCount) { + mSkipCount--; + return false; + } + + return chooseSkipCount(); + } + + /** + * Equivalent to calling trial() |n| times, and returning true if any of those + * calls do. However, like trial, this runs in fast constant time. + * + * What is this good for? In some applications, some events are "bigger" than + * others. For example, large allocations are more significant than small + * allocations. Perhaps we'd like to imagine that we're drawing allocations + * from a stream of bytes, and performing a separate Bernoulli trial on every + * byte from the stream. We can accomplish this by calling |t.trial(S)| for + * the number of bytes S, and sampling the event if that returns true. + * + * Of course, this style of sampling needs to be paired with analysis and + * presentation that makes the "size" of the event apparent, lest trials with + * large values for |n| appear to be indistinguishable from those with small + * values for |n|, despite being potentially much more likely to be sampled. + */ + bool trial(size_t aCount) { + if (mSkipCount > aCount) { + mSkipCount -= aCount; + return false; + } + + return chooseSkipCount(); + } + + void setRandomState(uint64_t aState0, uint64_t aState1) { + mGenerator.setState(aState0, aState1); + } + + void setProbability(double aProbability) { + MOZ_ASSERT(0 <= aProbability && aProbability <= 1); + mProbability = aProbability; + if (0 < mProbability && mProbability < 1) { + /* + * Let's look carefully at how this calculation plays out in floating- + * point arithmetic. We'll assume IEEE, but the final C++ code we arrive + * at would still be fine if our numbers were mathematically perfect. So, + * while we've considered IEEE's edge cases, we haven't done anything that + * should be actively bad when using other representations. + * + * (In the below, read comparisons as exact mathematical comparisons: when + * we say something "equals 1", that means it's exactly equal to 1. We + * treat approximation using intervals with open boundaries: saying a + * value is in (0,1) doesn't specify how close to 0 or 1 the value gets. + * When we use closed boundaries like [2**-53, 1], we're careful to ensure + * the boundary values are actually representable.) + * + * - After the comparison above, we know mProbability is in (0,1). + * + * - The gaps below 1 are 2**-53, so that interval is (0, 1-2**-53]. + * + * - Because the floating-point gaps near 1 are wider than those near + * zero, there are many small positive doubles ε such that 1-ε rounds to + * exactly 1. However, 2**-53 can be represented exactly. So + * 1-mProbability is in [2**-53, 1]. + * + * - log(1 - mProbability) is thus in (-37, 0]. + * + * That range includes zero, but when we use mInvLogNotProbability, it + * would be helpful if we could trust that it's negative. So when log(1 + * - mProbability) is 0, we'll just set mProbability to 0, so that + * mInvLogNotProbability is not used in chooseSkipCount. + * + * - How much of the range of mProbability does this cause us to ignore? + * The only value for which log returns 0 is exactly 1; the slope of log + * at 1 is 1, so for small ε such that 1 - ε != 1, log(1 - ε) is -ε, + * never 0. The gaps near one are larger than the gaps near zero, so if + * 1 - ε wasn't 1, then -ε is representable. So if log(1 - mProbability) + * isn't 0, then 1 - mProbability isn't 1, which means that mProbability + * is at least 2**-53, as discussed earlier. This is a sampling + * likelihood of roughly one in ten trillion, which is unlikely to be + * distinguishable from zero in practice. + * + * So by forbidding zero, we've tightened our range to (-37, -2**-53]. + * + * - Finally, 1 / log(1 - mProbability) is in [-2**53, -1/37). This all + * falls readily within the range of an IEEE double. + * + * ALL THAT HAVING BEEN SAID: here are the five lines of actual code: + */ + double logNotProbability = std::log(1 - mProbability); + if (logNotProbability == 0.0) + mProbability = 0.0; + else + mInvLogNotProbability = 1 / logNotProbability; + } + + chooseSkipCount(); + } + + private: + /* The likelihood that any given call to |trial| should return true. */ + double mProbability; + + /* + * The value of 1/std::log(1 - mProbability), cached for repeated use. + * + * If mProbability is exactly 0 or exactly 1, we don't use this value. + * Otherwise, we guarantee this value is in the range [-2**53, -1/37), i.e. + * definitely negative, as required by chooseSkipCount. See setProbability for + * the details. + */ + double mInvLogNotProbability; + + /* Our random number generator. */ + non_crypto::XorShift128PlusRNG mGenerator; + + /* The number of times |trial| should return false before next returning true. */ + size_t mSkipCount; + + /* + * Choose the next skip count. This also returns the value that |trial| should + * return, since we have to check for the extreme values for mProbability + * anyway, and |trial| should never return true at all when mProbability is 0. + */ + bool chooseSkipCount() { + /* + * If the probability is 1.0, every call to |trial| returns true. Make sure + * mSkipCount is 0. + */ + if (mProbability == 1.0) { + mSkipCount = 0; + return true; + } + + /* + * If the probabilility is zero, |trial| never returns true. Don't bother us + * for a while. + */ + if (mProbability == 0.0) { + mSkipCount = SIZE_MAX; + return false; + } + + /* + * What sorts of values can this call to std::floor produce? + * + * Since mGenerator.nextDouble returns a value in [0, 1-2**-53], std::log + * returns a value in the range [-infinity, -2**-53], all negative. Since + * mInvLogNotProbability is negative (see its comments), the product is + * positive and possibly infinite. std::floor returns +infinity unchanged. + * So the result will always be positive. + * + * Converting a double to an integer that is out of range for that integer + * is undefined behavior, so we must clamp our result to SIZE_MAX, to ensure + * we get an acceptable value for mSkipCount. + * + * The clamp is written carefully. Note that if we had said: + * + * if (skipCount > SIZE_MAX) + * skipCount = SIZE_MAX; + * + * that leads to undefined behavior 64-bit machines: SIZE_MAX coerced to + * double is 2^64, not 2^64-1, so this doesn't actually set skipCount to a + * value that can be safely assigned to mSkipCount. + * + * Jakub Oleson cleverly suggested flipping the sense of the comparison: if + * we require that skipCount < SIZE_MAX, then because of the gaps (2048) + * between doubles at that magnitude, the highest double less than 2^64 is + * 2^64 - 2048, which is fine to store in a size_t. + * + * (On 32-bit machines, all size_t values can be represented exactly in + * double, so all is well.) + */ + double skipCount = std::floor(std::log(mGenerator.nextDouble()) + * mInvLogNotProbability); + if (skipCount < SIZE_MAX) + mSkipCount = skipCount; + else + mSkipCount = SIZE_MAX; + + return true; + } +}; + +} /* namespace mozilla */ + +#endif /* mozilla_FastBernoulliTrial_h */ diff --git a/mfbt/FloatingPoint.cpp b/mfbt/FloatingPoint.cpp new file mode 100644 index 000000000..1ccae4600 --- /dev/null +++ b/mfbt/FloatingPoint.cpp @@ -0,0 +1,21 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Implementations of FloatingPoint functions */ + +#include "mozilla/FloatingPoint.h" + +namespace mozilla { + +bool +IsFloat32Representable(double aFloat32) +{ + float asFloat = static_cast<float>(aFloat32); + double floatAsDouble = static_cast<double>(asFloat); + return floatAsDouble == aFloat32; +} + +} /* namespace mozilla */ diff --git a/mfbt/FloatingPoint.h b/mfbt/FloatingPoint.h new file mode 100644 index 000000000..59afccd13 --- /dev/null +++ b/mfbt/FloatingPoint.h @@ -0,0 +1,479 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Various predicates and operations on IEEE-754 floating point types. */ + +#ifndef mozilla_FloatingPoint_h +#define mozilla_FloatingPoint_h + +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" +#include "mozilla/Casting.h" +#include "mozilla/MathAlgorithms.h" +#include "mozilla/Types.h" + +#include <stdint.h> + +namespace mozilla { + +/* + * It's reasonable to ask why we have this header at all. Don't isnan, + * copysign, the built-in comparison operators, and the like solve these + * problems? Unfortunately, they don't. We've found that various compilers + * (MSVC, MSVC when compiling with PGO, and GCC on OS X, at least) miscompile + * the standard methods in various situations, so we can't use them. Some of + * these compilers even have problems compiling seemingly reasonable bitwise + * algorithms! But with some care we've found algorithms that seem to not + * trigger those compiler bugs. + * + * For the aforementioned reasons, be very wary of making changes to any of + * these algorithms. If you must make changes, keep a careful eye out for + * compiler bustage, particularly PGO-specific bustage. + */ + +struct FloatTypeTraits +{ + typedef uint32_t Bits; + + static const unsigned kExponentBias = 127; + static const unsigned kExponentShift = 23; + + static const Bits kSignBit = 0x80000000UL; + static const Bits kExponentBits = 0x7F800000UL; + static const Bits kSignificandBits = 0x007FFFFFUL; +}; + +struct DoubleTypeTraits +{ + typedef uint64_t Bits; + + static const unsigned kExponentBias = 1023; + static const unsigned kExponentShift = 52; + + static const Bits kSignBit = 0x8000000000000000ULL; + static const Bits kExponentBits = 0x7ff0000000000000ULL; + static const Bits kSignificandBits = 0x000fffffffffffffULL; +}; + +template<typename T> struct SelectTrait; +template<> struct SelectTrait<float> : public FloatTypeTraits {}; +template<> struct SelectTrait<double> : public DoubleTypeTraits {}; + +/* + * This struct contains details regarding the encoding of floating-point + * numbers that can be useful for direct bit manipulation. As of now, the + * template parameter has to be float or double. + * + * The nested typedef |Bits| is the unsigned integral type with the same size + * as T: uint32_t for float and uint64_t for double (static assertions + * double-check these assumptions). + * + * kExponentBias is the offset that is subtracted from the exponent when + * computing the value, i.e. one plus the opposite of the mininum possible + * exponent. + * kExponentShift is the shift that one needs to apply to retrieve the + * exponent component of the value. + * + * kSignBit contains a bits mask. Bit-and-ing with this mask will result in + * obtaining the sign bit. + * kExponentBits contains the mask needed for obtaining the exponent bits and + * kSignificandBits contains the mask needed for obtaining the significand + * bits. + * + * Full details of how floating point number formats are encoded are beyond + * the scope of this comment. For more information, see + * http://en.wikipedia.org/wiki/IEEE_floating_point + * http://en.wikipedia.org/wiki/Floating_point#IEEE_754:_floating_point_in_modern_computers + */ +template<typename T> +struct FloatingPoint : public SelectTrait<T> +{ + typedef SelectTrait<T> Base; + typedef typename Base::Bits Bits; + + static_assert((Base::kSignBit & Base::kExponentBits) == 0, + "sign bit shouldn't overlap exponent bits"); + static_assert((Base::kSignBit & Base::kSignificandBits) == 0, + "sign bit shouldn't overlap significand bits"); + static_assert((Base::kExponentBits & Base::kSignificandBits) == 0, + "exponent bits shouldn't overlap significand bits"); + + static_assert((Base::kSignBit | Base::kExponentBits | Base::kSignificandBits) == + ~Bits(0), + "all bits accounted for"); + + /* + * These implementations assume float/double are 32/64-bit single/double + * format number types compatible with the IEEE-754 standard. C++ don't + * require this to be the case. But we required this in implementations of + * these algorithms that preceded this header, so we shouldn't break anything + * if we keep doing so. + */ + static_assert(sizeof(T) == sizeof(Bits), "Bits must be same size as T"); +}; + +/** Determines whether a float/double is NaN. */ +template<typename T> +static MOZ_ALWAYS_INLINE bool +IsNaN(T aValue) +{ + /* + * A float/double is NaN if all exponent bits are 1 and the significand + * contains at least one non-zero bit. + */ + typedef FloatingPoint<T> Traits; + typedef typename Traits::Bits Bits; + return (BitwiseCast<Bits>(aValue) & Traits::kExponentBits) == Traits::kExponentBits && + (BitwiseCast<Bits>(aValue) & Traits::kSignificandBits) != 0; +} + +/** Determines whether a float/double is +Infinity or -Infinity. */ +template<typename T> +static MOZ_ALWAYS_INLINE bool +IsInfinite(T aValue) +{ + /* Infinities have all exponent bits set to 1 and an all-0 significand. */ + typedef FloatingPoint<T> Traits; + typedef typename Traits::Bits Bits; + Bits bits = BitwiseCast<Bits>(aValue); + return (bits & ~Traits::kSignBit) == Traits::kExponentBits; +} + +/** Determines whether a float/double is not NaN or infinite. */ +template<typename T> +static MOZ_ALWAYS_INLINE bool +IsFinite(T aValue) +{ + /* + * NaN and Infinities are the only non-finite floats/doubles, and both have + * all exponent bits set to 1. + */ + typedef FloatingPoint<T> Traits; + typedef typename Traits::Bits Bits; + Bits bits = BitwiseCast<Bits>(aValue); + return (bits & Traits::kExponentBits) != Traits::kExponentBits; +} + +/** + * Determines whether a float/double is negative or -0. It is an error + * to call this method on a float/double which is NaN. + */ +template<typename T> +static MOZ_ALWAYS_INLINE bool +IsNegative(T aValue) +{ + MOZ_ASSERT(!IsNaN(aValue), "NaN does not have a sign"); + + /* The sign bit is set if the double is negative. */ + typedef FloatingPoint<T> Traits; + typedef typename Traits::Bits Bits; + Bits bits = BitwiseCast<Bits>(aValue); + return (bits & Traits::kSignBit) != 0; +} + +/** Determines whether a float/double represents -0. */ +template<typename T> +static MOZ_ALWAYS_INLINE bool +IsNegativeZero(T aValue) +{ + /* Only the sign bit is set if the value is -0. */ + typedef FloatingPoint<T> Traits; + typedef typename Traits::Bits Bits; + Bits bits = BitwiseCast<Bits>(aValue); + return bits == Traits::kSignBit; +} + +/** Determines wether a float/double represents +0. */ +template<typename T> +static MOZ_ALWAYS_INLINE bool +IsPositiveZero(T aValue) +{ + /* All bits are zero if the value is +0. */ + typedef FloatingPoint<T> Traits; + typedef typename Traits::Bits Bits; + Bits bits = BitwiseCast<Bits>(aValue); + return bits == 0; +} + +/** + * Returns 0 if a float/double is NaN or infinite; + * otherwise, the float/double is returned. + */ +template<typename T> +static MOZ_ALWAYS_INLINE T +ToZeroIfNonfinite(T aValue) +{ + return IsFinite(aValue) ? aValue : 0; +} + +/** + * Returns the exponent portion of the float/double. + * + * Zero is not special-cased, so ExponentComponent(0.0) is + * -int_fast16_t(Traits::kExponentBias). + */ +template<typename T> +static MOZ_ALWAYS_INLINE int_fast16_t +ExponentComponent(T aValue) +{ + /* + * The exponent component of a float/double is an unsigned number, biased + * from its actual value. Subtract the bias to retrieve the actual exponent. + */ + typedef FloatingPoint<T> Traits; + typedef typename Traits::Bits Bits; + Bits bits = BitwiseCast<Bits>(aValue); + return int_fast16_t((bits & Traits::kExponentBits) >> Traits::kExponentShift) - + int_fast16_t(Traits::kExponentBias); +} + +/** Returns +Infinity. */ +template<typename T> +static MOZ_ALWAYS_INLINE T +PositiveInfinity() +{ + /* + * Positive infinity has all exponent bits set, sign bit set to 0, and no + * significand. + */ + typedef FloatingPoint<T> Traits; + return BitwiseCast<T>(Traits::kExponentBits); +} + +/** Returns -Infinity. */ +template<typename T> +static MOZ_ALWAYS_INLINE T +NegativeInfinity() +{ + /* + * Negative infinity has all exponent bits set, sign bit set to 1, and no + * significand. + */ + typedef FloatingPoint<T> Traits; + return BitwiseCast<T>(Traits::kSignBit | Traits::kExponentBits); +} + +/** + * Computes the bit pattern for a NaN with the specified sign bit and + * significand bits. + */ +template<typename T, + int SignBit, + typename FloatingPoint<T>::Bits Significand> +struct SpecificNaNBits +{ + using Traits = FloatingPoint<T>; + + static_assert(SignBit == 0 || SignBit == 1, "bad sign bit"); + static_assert((Significand & ~Traits::kSignificandBits) == 0, + "significand must only have significand bits set"); + static_assert(Significand & Traits::kSignificandBits, + "significand must be nonzero"); + + static constexpr typename Traits::Bits value = + (SignBit * Traits::kSignBit) | Traits::kExponentBits | Significand; +}; + +/** + * Constructs a NaN value with the specified sign bit and significand bits. + * + * There is also a variant that returns the value directly. In most cases, the + * two variants should be identical. However, in the specific case of x86 + * chips, the behavior differs: returning floating-point values directly is done + * through the x87 stack, and x87 loads and stores turn signaling NaNs into + * quiet NaNs... silently. Returning floating-point values via outparam, + * however, is done entirely within the SSE registers when SSE2 floating-point + * is enabled in the compiler, which has semantics-preserving behavior you would + * expect. + * + * If preserving the distinction between signaling NaNs and quiet NaNs is + * important to you, you should use the outparam version. In all other cases, + * you should use the direct return version. + */ +template<typename T> +static MOZ_ALWAYS_INLINE void +SpecificNaN(int signbit, typename FloatingPoint<T>::Bits significand, T* result) +{ + typedef FloatingPoint<T> Traits; + MOZ_ASSERT(signbit == 0 || signbit == 1); + MOZ_ASSERT((significand & ~Traits::kSignificandBits) == 0); + MOZ_ASSERT(significand & Traits::kSignificandBits); + + BitwiseCast<T>((signbit ? Traits::kSignBit : 0) | + Traits::kExponentBits | + significand, + result); + MOZ_ASSERT(IsNaN(*result)); +} + +template<typename T> +static MOZ_ALWAYS_INLINE T +SpecificNaN(int signbit, typename FloatingPoint<T>::Bits significand) +{ + T t; + SpecificNaN(signbit, significand, &t); + return t; +} + +/** Computes the smallest non-zero positive float/double value. */ +template<typename T> +static MOZ_ALWAYS_INLINE T +MinNumberValue() +{ + typedef FloatingPoint<T> Traits; + typedef typename Traits::Bits Bits; + return BitwiseCast<T>(Bits(1)); +} + +/** + * If aValue is equal to some int32_t value, set *aInt32 to that value and + * return true; otherwise return false. + * + * Note that negative zero is "equal" to zero here. To test whether a value can + * be losslessly converted to int32_t and back, use NumberIsInt32 instead. + */ +template<typename T> +static MOZ_ALWAYS_INLINE bool +NumberEqualsInt32(T aValue, int32_t* aInt32) +{ + /* + * XXX Casting a floating-point value that doesn't truncate to int32_t, to + * int32_t, induces undefined behavior. We should definitely fix this + * (bug 744965), but as apparently it "works" in practice, it's not a + * pressing concern now. + */ + return aValue == (*aInt32 = int32_t(aValue)); +} + +/** + * If d can be converted to int32_t and back to an identical double value, + * set *aInt32 to that value and return true; otherwise return false. + * + * The difference between this and NumberEqualsInt32 is that this method returns + * false for negative zero. + */ +template<typename T> +static MOZ_ALWAYS_INLINE bool +NumberIsInt32(T aValue, int32_t* aInt32) +{ + return !IsNegativeZero(aValue) && NumberEqualsInt32(aValue, aInt32); +} + +/** + * Computes a NaN value. Do not use this method if you depend upon a particular + * NaN value being returned. + */ +template<typename T> +static MOZ_ALWAYS_INLINE T +UnspecifiedNaN() +{ + /* + * If we can use any quiet NaN, we might as well use the all-ones NaN, + * since it's cheap to materialize on common platforms (such as x64, where + * this value can be represented in a 32-bit signed immediate field, allowing + * it to be stored to memory in a single instruction). + */ + typedef FloatingPoint<T> Traits; + return SpecificNaN<T>(1, Traits::kSignificandBits); +} + +/** + * Compare two doubles for equality, *without* equating -0 to +0, and equating + * any NaN value to any other NaN value. (The normal equality operators equate + * -0 with +0, and they equate NaN to no other value.) + */ +template<typename T> +static inline bool +NumbersAreIdentical(T aValue1, T aValue2) +{ + typedef FloatingPoint<T> Traits; + typedef typename Traits::Bits Bits; + if (IsNaN(aValue1)) { + return IsNaN(aValue2); + } + return BitwiseCast<Bits>(aValue1) == BitwiseCast<Bits>(aValue2); +} + +namespace detail { + +template<typename T> +struct FuzzyEqualsEpsilon; + +template<> +struct FuzzyEqualsEpsilon<float> +{ + // A number near 1e-5 that is exactly representable in a float. + static float value() { return 1.0f / (1 << 17); } +}; + +template<> +struct FuzzyEqualsEpsilon<double> +{ + // A number near 1e-12 that is exactly representable in a double. + static double value() { return 1.0 / (1LL << 40); } +}; + +} // namespace detail + +/** + * Compare two floating point values for equality, modulo rounding error. That + * is, the two values are considered equal if they are both not NaN and if they + * are less than or equal to aEpsilon apart. The default value of aEpsilon is + * near 1e-5. + * + * For most scenarios you will want to use FuzzyEqualsMultiplicative instead, + * as it is more reasonable over the entire range of floating point numbers. + * This additive version should only be used if you know the range of the + * numbers you are dealing with is bounded and stays around the same order of + * magnitude. + */ +template<typename T> +static MOZ_ALWAYS_INLINE bool +FuzzyEqualsAdditive(T aValue1, T aValue2, + T aEpsilon = detail::FuzzyEqualsEpsilon<T>::value()) +{ + static_assert(IsFloatingPoint<T>::value, "floating point type required"); + return Abs(aValue1 - aValue2) <= aEpsilon; +} + +/** + * Compare two floating point values for equality, allowing for rounding error + * relative to the magnitude of the values. That is, the two values are + * considered equal if they are both not NaN and they are less than or equal to + * some aEpsilon apart, where the aEpsilon is scaled by the smaller of the two + * argument values. + * + * In most cases you will want to use this rather than FuzzyEqualsAdditive, as + * this function effectively masks out differences in the bottom few bits of + * the floating point numbers being compared, regardless of what order of + * magnitude those numbers are at. + */ +template<typename T> +static MOZ_ALWAYS_INLINE bool +FuzzyEqualsMultiplicative(T aValue1, T aValue2, + T aEpsilon = detail::FuzzyEqualsEpsilon<T>::value()) +{ + static_assert(IsFloatingPoint<T>::value, "floating point type required"); + // can't use std::min because of bug 965340 + T smaller = Abs(aValue1) < Abs(aValue2) ? Abs(aValue1) : Abs(aValue2); + return Abs(aValue1 - aValue2) <= aEpsilon * smaller; +} + +/** + * Returns true if the given value can be losslessly represented as an IEEE-754 + * single format number, false otherwise. All NaN values are considered + * representable (notwithstanding that the exact bit pattern of a double format + * NaN value can't be exactly represented in single format). + * + * This function isn't inlined to avoid buggy optimizations by MSVC. + */ +MOZ_MUST_USE +extern MFBT_API bool +IsFloat32Representable(double aFloat32); + +} /* namespace mozilla */ + +#endif /* mozilla_FloatingPoint_h */ diff --git a/mfbt/Function.h b/mfbt/Function.h new file mode 100644 index 000000000..d6de9c833 --- /dev/null +++ b/mfbt/Function.h @@ -0,0 +1,223 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* A type-erased callable wrapper. */ + +#ifndef mozilla_Function_h +#define mozilla_Function_h + +#include "mozilla/Attributes.h" // for MOZ_IMPLICIT +#include "mozilla/Move.h" +#include "mozilla/RefCounted.h" +#include "mozilla/RefPtr.h" + +// |function<Signature>| is a wrapper that can hold any type of callable +// object that can be invoked in a way that's compatible with |Signature|. +// The standard "type erasure" technique is used to avoid the type of the +// wrapper depending on the concrete type of the wrapped callable. +// +// Supported callable types include non-member functions, static member +// functions, and function objects (that is to say, objects with an overloaded +// call operator; this includes C++11 lambdas). Member functions aren't +// directly supported; they first need to be wrapped into a function object +// using |std::mem_fn()| or an equivalent. +// +// |Signature| is a type of the form |ReturnType(Arguments...)|. Syntactically, +// this is a function type; it's not used in any way other than serving as a +// vehicle to encode the return and argument types into a single type. +// +// |function| is default-constructible. A default-constructed instance is +// considered "empty". Invoking an empty instance is undefined behaviour. +// An empty instance can be populated with a callable by assigning to it. +// +// This class is intended to provide functionality similar to the C++11 +// standard library class |std::function|. + +namespace mozilla { + +namespace detail { + +template<typename ReturnType, typename... Arguments> +class FunctionImplBase : public mozilla::RefCounted<FunctionImplBase<ReturnType, Arguments...>> +{ +public: + MOZ_DECLARE_REFCOUNTED_TYPENAME(FunctionImplBase) + + virtual ~FunctionImplBase() {} + virtual ReturnType call(Arguments... aArguments) = 0; +}; + +// Normal Callable Object. +template <typename Callable, typename ReturnType, typename... Arguments> +class FunctionImpl : public FunctionImplBase<ReturnType, Arguments...> +{ + public: + explicit FunctionImpl(const Callable& aCallable) + : mCallable(aCallable) {} + + ReturnType call(Arguments... aArguments) override + { + return mCallable(Forward<Arguments>(aArguments)...); + } + private: + Callable mCallable; +}; + +// Base class for passing pointer to member function. +template <typename Callable, typename ReturnType, typename... Arguments> +class MemberFunctionImplBase : public FunctionImplBase<ReturnType, Arguments...> +{ +public: + explicit MemberFunctionImplBase(const Callable& aCallable) + : mCallable(aCallable) {} + + ReturnType call(Arguments... aArguments) override + { + return callInternal(Forward<Arguments>(aArguments)...); + } +private: + template<typename ThisType, typename... Args> + ReturnType callInternal(ThisType* aThis, Args&&... aArguments) + { + return (aThis->*mCallable)(Forward<Args>(aArguments)...); + } + + template<typename ThisType, typename... Args> + ReturnType callInternal(ThisType&& aThis, Args&&... aArguments) + { + return (aThis.*mCallable)(Forward<Args>(aArguments)...); + } + Callable mCallable; +}; + +// For non-const member function specialization of FunctionImpl. +template <typename ThisType, typename... Args, typename ReturnType, typename... Arguments> +class FunctionImpl<ReturnType(ThisType::*)(Args...), + ReturnType, Arguments...> + : public MemberFunctionImplBase<ReturnType(ThisType::*)(Args...), + ReturnType, Arguments...> +{ +public: + explicit FunctionImpl(ReturnType(ThisType::*aMemberFunc)(Args...)) + : MemberFunctionImplBase<ReturnType(ThisType::*)(Args...), + ReturnType, Arguments...>(aMemberFunc) + {} +}; + +// For const member function specialization of FunctionImpl. +template <typename ThisType, typename... Args, typename ReturnType, typename... Arguments> +class FunctionImpl<ReturnType(ThisType::*)(Args...) const, + ReturnType, Arguments...> + : public MemberFunctionImplBase<ReturnType(ThisType::*)(Args...) const, + ReturnType, Arguments...> +{ +public: + explicit FunctionImpl(ReturnType(ThisType::*aConstMemberFunc)(Args...) const) + : MemberFunctionImplBase<ReturnType(ThisType::*)(Args...) const, + ReturnType, Arguments...>(aConstMemberFunc) + {} +}; + +} // namespace detail + +// The primary template is never defined. As |Signature| is required to be +// of the form |ReturnType(Arguments...)|, we only define a partial +// specialization that matches this form. This allows us to use |ReturnType| +// and |Arguments| in the definition of the specialization without having to +// introspect |Signature|. +template<typename Signature> +class function; + +template<typename ReturnType, typename... Arguments> +class function<ReturnType(Arguments...)> +{ +public: + function() {} + + // This constructor is implicit to match the interface of |std::function|. + template <typename Callable> + MOZ_IMPLICIT function(const Callable& aCallable) + : mImpl(new detail::FunctionImpl<Callable, ReturnType, Arguments...>(aCallable)) + {} + MOZ_IMPLICIT function(const function& aFunction) + : mImpl(aFunction.mImpl) + {} + MOZ_IMPLICIT function(decltype(nullptr)) + {} + + // Move constructor and move assingment operator. + // These should be generated automatically, but MSVC doesn't do that yet. + function(function&& aOther) : mImpl(Move(aOther.mImpl)) {} + function& operator=(function&& aOther) { + mImpl = Move(aOther.mImpl); + return *this; + } + + template <typename Callable> + function& operator=(const Callable& aCallable) + { + mImpl = new detail::FunctionImpl<Callable, ReturnType, Arguments...>(aCallable); + return *this; + } + function& operator=(const function& aFunction) + { + mImpl = aFunction.mImpl; + return *this; + } + function& operator=(decltype(nullptr)) + { + mImpl = nullptr; + return *this; + } + + template<typename... Args> + ReturnType operator()(Args&&... aArguments) const + { + MOZ_ASSERT(mImpl); + return mImpl->call(Forward<Args>(aArguments)...); + } + + explicit operator bool() const + { + return bool(mImpl); + } + +private: + // TODO: Consider implementing a small object optimization. + RefPtr<detail::FunctionImplBase<ReturnType, Arguments...>> mImpl; +}; + +template<typename Signature> +bool +operator==(const function<Signature>& aX, decltype(nullptr)) +{ + return !aX; +} + +template<typename Signature> +bool +operator==(decltype(nullptr), const function<Signature>& aX) +{ + return !aX; +} + +template<typename Signature> +bool +operator!=(const function<Signature>& aX, decltype(nullptr)) +{ + return bool(aX); +} + +template<typename Signature> +bool +operator!=(decltype(nullptr), const function<Signature>& aX) +{ + return bool(aX); +} + +} // namespace mozilla + +#endif /* mozilla_Function_h */ diff --git a/mfbt/GuardObjects.h b/mfbt/GuardObjects.h new file mode 100644 index 000000000..9440c71c4 --- /dev/null +++ b/mfbt/GuardObjects.h @@ -0,0 +1,167 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Implementation of macros to ensure correct use of RAII Auto* objects. */ + +#ifndef mozilla_GuardObjects_h +#define mozilla_GuardObjects_h + +#include "mozilla/Assertions.h" +#include "mozilla/Move.h" +#include "mozilla/Types.h" + +#ifdef __cplusplus + +#ifdef DEBUG + +/** + * A custom define is used rather than |mozPoisonValue()| due to cascading + * build failures relating to how mfbt is linked on different operating + * systems. See bug 1160253. + */ +#define MOZ_POISON uintptr_t(-1) + +namespace mozilla { +namespace detail { + +/* + * The following classes are designed to cause assertions to detect + * inadvertent use of guard objects as temporaries. In other words, + * when we have a guard object whose only purpose is its constructor and + * destructor (and is never otherwise referenced), the intended use + * might be: + * + * AutoRestore savePainting(mIsPainting); + * + * but is is easy to accidentally write: + * + * AutoRestore(mIsPainting); + * + * which compiles just fine, but runs the destructor well before the + * intended time. + * + * They work by adding (#ifdef DEBUG) an additional parameter to the + * guard object's constructor, with a default value, so that users of + * the guard object's API do not need to do anything. The default value + * of this parameter is a temporary object. C++ (ISO/IEC 14882:1998), + * section 12.2 [class.temporary], clauses 4 and 5 seem to assume a + * guarantee that temporaries are destroyed in the reverse of their + * construction order, but I actually can't find a statement that that + * is true in the general case (beyond the two specific cases mentioned + * there). However, it seems to be true. + * + * These classes are intended to be used only via the macros immediately + * below them: + * + * MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER declares (ifdef DEBUG) a member + * variable, and should be put where a declaration of a private + * member variable would be placed. + * MOZ_GUARD_OBJECT_NOTIFIER_PARAM should be placed at the end of the + * parameters to each constructor of the guard object; it declares + * (ifdef DEBUG) an additional parameter. (But use the *_ONLY_PARAM + * variant for constructors that take no other parameters.) + * MOZ_GUARD_OBJECT_NOTIFIER_PARAM_IN_IMPL should likewise be used in + * the implementation of such constructors when they are not inline. + * MOZ_GUARD_OBJECT_NOTIFIER_PARAM_TO_PARENT should be used in + * the implementation of such constructors to pass the parameter to + * a base class that also uses these macros + * MOZ_GUARD_OBJECT_NOTIFIER_INIT is a statement that belongs in each + * constructor. It uses the parameter declared by + * MOZ_GUARD_OBJECT_NOTIFIER_PARAM. + * + * For more details, and examples of using these macros, see + * https://developer.mozilla.org/en/Using_RAII_classes_in_Mozilla + */ +class GuardObjectNotifier +{ +private: + bool* mStatementDone; + +public: + GuardObjectNotifier() + : mStatementDone(reinterpret_cast<bool*>(MOZ_POISON)) + { + } + + ~GuardObjectNotifier() + { + // Assert that the GuardObjectNotifier has been properly initialized by + // using the |MOZ_GUARD_OBJECT_NOTIFIER_INIT| macro. A poison value is + // used rather than a null check to appease static analyzers that were + // (incorrectly) detecting null pointer dereferences. + MOZ_ASSERT(mStatementDone != reinterpret_cast<bool*>(MOZ_POISON)); + *mStatementDone = true; + } + + void setStatementDone(bool* aStatementIsDone) + { + mStatementDone = aStatementIsDone; + } +}; + +class GuardObjectNotificationReceiver +{ +private: + bool mStatementDone; + +public: + GuardObjectNotificationReceiver() : mStatementDone(false) { } + + ~GuardObjectNotificationReceiver() { + /* + * Assert that the guard object was not used as a temporary. (Note that + * this assert might also fire if init is not called because the guard + * object's implementation is not using the above macros correctly.) + */ + MOZ_ASSERT(mStatementDone); + } + + void init(GuardObjectNotifier& aNotifier) + { + aNotifier.setStatementDone(&mStatementDone); + } +}; + +} /* namespace detail */ +} /* namespace mozilla */ + +#undef MOZ_POISON + +#endif /* DEBUG */ + +#ifdef DEBUG +# define MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER \ + mozilla::detail::GuardObjectNotificationReceiver _mCheckNotUsedAsTemporary; +# define MOZ_GUARD_OBJECT_NOTIFIER_PARAM \ + , mozilla::detail::GuardObjectNotifier&& _notifier = \ + mozilla::detail::GuardObjectNotifier() +# define MOZ_GUARD_OBJECT_NOTIFIER_ONLY_PARAM \ + mozilla::detail::GuardObjectNotifier&& _notifier = \ + mozilla::detail::GuardObjectNotifier() +# define MOZ_GUARD_OBJECT_NOTIFIER_PARAM_IN_IMPL \ + , mozilla::detail::GuardObjectNotifier&& _notifier +# define MOZ_GUARD_OBJECT_NOTIFIER_ONLY_PARAM_IN_IMPL \ + mozilla::detail::GuardObjectNotifier&& _notifier +# define MOZ_GUARD_OBJECT_NOTIFIER_PARAM_TO_PARENT \ + , mozilla::Move(_notifier) +# define MOZ_GUARD_OBJECT_NOTIFIER_ONLY_PARAM_TO_PARENT \ + mozilla::Move(_notifier) +# define MOZ_GUARD_OBJECT_NOTIFIER_INIT \ + do { _mCheckNotUsedAsTemporary.init(_notifier); } while (0) +#else +# define MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER +# define MOZ_GUARD_OBJECT_NOTIFIER_PARAM +# define MOZ_GUARD_OBJECT_NOTIFIER_ONLY_PARAM +# define MOZ_GUARD_OBJECT_NOTIFIER_PARAM_IN_IMPL +# define MOZ_GUARD_OBJECT_NOTIFIER_ONLY_PARAM_IN_IMPL +# define MOZ_GUARD_OBJECT_NOTIFIER_ONLY_PARAM_TO_PARENT +# define MOZ_GUARD_OBJECT_NOTIFIER_PARAM_TO_PARENT +# define MOZ_GUARD_OBJECT_NOTIFIER_INIT do { } while (0) +#endif + +#endif /* __cplusplus */ + +#endif /* mozilla_GuardObjects_h */ diff --git a/mfbt/HashFunctions.cpp b/mfbt/HashFunctions.cpp new file mode 100644 index 000000000..3273e1788 --- /dev/null +++ b/mfbt/HashFunctions.cpp @@ -0,0 +1,39 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Implementations of hash functions. */ + +#include "mozilla/HashFunctions.h" +#include "mozilla/Types.h" + +#include <string.h> + +namespace mozilla { + +uint32_t +HashBytes(const void* aBytes, size_t aLength) +{ + uint32_t hash = 0; + const char* b = reinterpret_cast<const char*>(aBytes); + + /* Walk word by word. */ + size_t i = 0; + for (; i < aLength - (aLength % sizeof(size_t)); i += sizeof(size_t)) { + /* Do an explicitly unaligned load of the data. */ + size_t data; + memcpy(&data, b + i, sizeof(size_t)); + + hash = AddToHash(hash, data, sizeof(data)); + } + + /* Get the remaining bytes. */ + for (; i < aLength; i++) { + hash = AddToHash(hash, b[i]); + } + return hash; +} + +} /* namespace mozilla */ diff --git a/mfbt/HashFunctions.h b/mfbt/HashFunctions.h new file mode 100644 index 000000000..eeb192c36 --- /dev/null +++ b/mfbt/HashFunctions.h @@ -0,0 +1,389 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Utilities for hashing. */ + +/* + * This file exports functions for hashing data down to a 32-bit value, + * including: + * + * - HashString Hash a char* or char16_t/wchar_t* of known or unknown + * length. + * + * - HashBytes Hash a byte array of known length. + * + * - HashGeneric Hash one or more values. Currently, we support uint32_t, + * types which can be implicitly cast to uint32_t, data + * pointers, and function pointers. + * + * - AddToHash Add one or more values to the given hash. This supports the + * same list of types as HashGeneric. + * + * + * You can chain these functions together to hash complex objects. For example: + * + * class ComplexObject + * { + * char* mStr; + * uint32_t mUint1, mUint2; + * void (*mCallbackFn)(); + * + * public: + * uint32_t hash() + * { + * uint32_t hash = HashString(mStr); + * hash = AddToHash(hash, mUint1, mUint2); + * return AddToHash(hash, mCallbackFn); + * } + * }; + * + * If you want to hash an nsAString or nsACString, use the HashString functions + * in nsHashKeys.h. + */ + +#ifndef mozilla_HashFunctions_h +#define mozilla_HashFunctions_h + +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" +#include "mozilla/Char16.h" +#include "mozilla/MathAlgorithms.h" +#include "mozilla/Types.h" + +#include <stdint.h> + +#ifdef __cplusplus +namespace mozilla { + +/** + * The golden ratio as a 32-bit fixed-point value. + */ +static const uint32_t kGoldenRatioU32 = 0x9E3779B9U; + +inline uint32_t +RotateBitsLeft32(uint32_t aValue, uint8_t aBits) +{ + MOZ_ASSERT(aBits < 32); + return (aValue << aBits) | (aValue >> (32 - aBits)); +} + +namespace detail { + +inline uint32_t +AddU32ToHash(uint32_t aHash, uint32_t aValue) +{ + /* + * This is the meat of all our hash routines. This hash function is not + * particularly sophisticated, but it seems to work well for our mostly + * plain-text inputs. Implementation notes follow. + * + * Our use of the golden ratio here is arbitrary; we could pick almost any + * number which: + * + * * is odd (because otherwise, all our hash values will be even) + * + * * has a reasonably-even mix of 1's and 0's (consider the extreme case + * where we multiply by 0x3 or 0xeffffff -- this will not produce good + * mixing across all bits of the hash). + * + * The rotation length of 5 is also arbitrary, although an odd number is again + * preferable so our hash explores the whole universe of possible rotations. + * + * Finally, we multiply by the golden ratio *after* xor'ing, not before. + * Otherwise, if |aHash| is 0 (as it often is for the beginning of a + * message), the expression + * + * (kGoldenRatioU32 * RotateBitsLeft(aHash, 5)) |xor| aValue + * + * evaluates to |aValue|. + * + * (Number-theoretic aside: Because any odd number |m| is relatively prime to + * our modulus (2^32), the list + * + * [x * m (mod 2^32) for 0 <= x < 2^32] + * + * has no duplicate elements. This means that multiplying by |m| does not + * cause us to skip any possible hash values. + * + * It's also nice if |m| has large-ish order mod 2^32 -- that is, if the + * smallest k such that m^k == 1 (mod 2^32) is large -- so we can safely + * multiply our hash value by |m| a few times without negating the + * multiplicative effect. Our golden ratio constant has order 2^29, which is + * more than enough for our purposes.) + */ + return kGoldenRatioU32 * (RotateBitsLeft32(aHash, 5) ^ aValue); +} + +/** + * AddUintptrToHash takes sizeof(uintptr_t) as a template parameter. + */ +template<size_t PtrSize> +inline uint32_t +AddUintptrToHash(uint32_t aHash, uintptr_t aValue); + +template<> +inline uint32_t +AddUintptrToHash<4>(uint32_t aHash, uintptr_t aValue) +{ + return AddU32ToHash(aHash, static_cast<uint32_t>(aValue)); +} + +template<> +inline uint32_t +AddUintptrToHash<8>(uint32_t aHash, uintptr_t aValue) +{ + /* + * The static cast to uint64_t below is necessary because this function + * sometimes gets compiled on 32-bit platforms (yes, even though it's a + * template and we never call this particular override in a 32-bit build). If + * we do aValue >> 32 on a 32-bit machine, we're shifting a 32-bit uintptr_t + * right 32 bits, and the compiler throws an error. + */ + uint32_t v1 = static_cast<uint32_t>(aValue); + uint32_t v2 = static_cast<uint32_t>(static_cast<uint64_t>(aValue) >> 32); + return AddU32ToHash(AddU32ToHash(aHash, v1), v2); +} + +} /* namespace detail */ + +/** + * AddToHash takes a hash and some values and returns a new hash based on the + * inputs. + * + * Currently, we support hashing uint32_t's, values which we can implicitly + * convert to uint32_t, data pointers, and function pointers. + */ +template<typename A> +MOZ_MUST_USE inline uint32_t +AddToHash(uint32_t aHash, A aA) +{ + /* + * Try to convert |A| to uint32_t implicitly. If this works, great. If not, + * we'll error out. + */ + return detail::AddU32ToHash(aHash, aA); +} + +template<typename A> +MOZ_MUST_USE inline uint32_t +AddToHash(uint32_t aHash, A* aA) +{ + /* + * You might think this function should just take a void*. But then we'd only + * catch data pointers and couldn't handle function pointers. + */ + + static_assert(sizeof(aA) == sizeof(uintptr_t), "Strange pointer!"); + + return detail::AddUintptrToHash<sizeof(uintptr_t)>(aHash, uintptr_t(aA)); +} + +template<> +MOZ_MUST_USE inline uint32_t +AddToHash(uint32_t aHash, uintptr_t aA) +{ + return detail::AddUintptrToHash<sizeof(uintptr_t)>(aHash, aA); +} + +template<typename A, typename... Args> +MOZ_MUST_USE uint32_t +AddToHash(uint32_t aHash, A aArg, Args... aArgs) +{ + return AddToHash(AddToHash(aHash, aArg), aArgs...); +} + +/** + * The HashGeneric class of functions let you hash one or more values. + * + * If you want to hash together two values x and y, calling HashGeneric(x, y) is + * much better than calling AddToHash(x, y), because AddToHash(x, y) assumes + * that x has already been hashed. + */ +template<typename... Args> +MOZ_MUST_USE inline uint32_t +HashGeneric(Args... aArgs) +{ + return AddToHash(0, aArgs...); +} + +namespace detail { + +template<typename T> +uint32_t +HashUntilZero(const T* aStr) +{ + uint32_t hash = 0; + for (T c; (c = *aStr); aStr++) { + hash = AddToHash(hash, c); + } + return hash; +} + +template<typename T> +uint32_t +HashKnownLength(const T* aStr, size_t aLength) +{ + uint32_t hash = 0; + for (size_t i = 0; i < aLength; i++) { + hash = AddToHash(hash, aStr[i]); + } + return hash; +} + +} /* namespace detail */ + +/** + * The HashString overloads below do just what you'd expect. + * + * If you have the string's length, you might as well call the overload which + * includes the length. It may be marginally faster. + */ +MOZ_MUST_USE inline uint32_t +HashString(const char* aStr) +{ + return detail::HashUntilZero(reinterpret_cast<const unsigned char*>(aStr)); +} + +MOZ_MUST_USE inline uint32_t +HashString(const char* aStr, size_t aLength) +{ + return detail::HashKnownLength(reinterpret_cast<const unsigned char*>(aStr), aLength); +} + +MOZ_MUST_USE +inline uint32_t +HashString(const unsigned char* aStr, size_t aLength) +{ + return detail::HashKnownLength(aStr, aLength); +} + +MOZ_MUST_USE inline uint32_t +HashString(const char16_t* aStr) +{ + return detail::HashUntilZero(aStr); +} + +MOZ_MUST_USE inline uint32_t +HashString(const char16_t* aStr, size_t aLength) +{ + return detail::HashKnownLength(aStr, aLength); +} + +/* + * On Windows, wchar_t is not the same as char16_t, even though it's + * the same width! + */ +#ifdef WIN32 +MOZ_MUST_USE inline uint32_t +HashString(const wchar_t* aStr) +{ + return detail::HashUntilZero(aStr); +} + +MOZ_MUST_USE inline uint32_t +HashString(const wchar_t* aStr, size_t aLength) +{ + return detail::HashKnownLength(aStr, aLength); +} +#endif + +/** + * Hash some number of bytes. + * + * This hash walks word-by-word, rather than byte-by-byte, so you won't get the + * same result out of HashBytes as you would out of HashString. + */ +MOZ_MUST_USE extern MFBT_API uint32_t +HashBytes(const void* bytes, size_t aLength); + +/** + * A pseudorandom function mapping 32-bit integers to 32-bit integers. + * + * This is for when you're feeding private data (like pointer values or credit + * card numbers) to a non-crypto hash function (like HashBytes) and then using + * the hash code for something that untrusted parties could observe (like a JS + * Map). Plug in a HashCodeScrambler before that last step to avoid leaking the + * private data. + * + * By itself, this does not prevent hash-flooding DoS attacks, because an + * attacker can still generate many values with exactly equal hash codes by + * attacking the non-crypto hash function alone. Equal hash codes will, of + * course, still be equal however much you scramble them. + * + * The algorithm is SipHash-1-3. See <https://131002.net/siphash/>. + */ +class HashCodeScrambler +{ + struct SipHasher; + + uint64_t mK0, mK1; + +public: + /** Creates a new scrambler with the given 128-bit key. */ + constexpr HashCodeScrambler(uint64_t aK0, uint64_t aK1) : mK0(aK0), mK1(aK1) {} + + /** + * Scramble a hash code. Always produces the same result for the same + * combination of key and hash code. + */ + uint32_t scramble(uint32_t aHashCode) const + { + SipHasher hasher(mK0, mK1); + return uint32_t(hasher.sipHash(aHashCode)); + } + +private: + struct SipHasher + { + SipHasher(uint64_t aK0, uint64_t aK1) + { + // 1. Initialization. + mV0 = aK0 ^ UINT64_C(0x736f6d6570736575); + mV1 = aK1 ^ UINT64_C(0x646f72616e646f6d); + mV2 = aK0 ^ UINT64_C(0x6c7967656e657261); + mV3 = aK1 ^ UINT64_C(0x7465646279746573); + } + + uint64_t sipHash(uint64_t aM) + { + // 2. Compression. + mV3 ^= aM; + sipRound(); + mV0 ^= aM; + + // 3. Finalization. + mV2 ^= 0xff; + for (int i = 0; i < 3; i++) + sipRound(); + return mV0 ^ mV1 ^ mV2 ^ mV3; + } + + void sipRound() + { + mV0 += mV1; + mV1 = RotateLeft(mV1, 13); + mV1 ^= mV0; + mV0 = RotateLeft(mV0, 32); + mV2 += mV3; + mV3 = RotateLeft(mV3, 16); + mV3 ^= mV2; + mV0 += mV3; + mV3 = RotateLeft(mV3, 21); + mV3 ^= mV0; + mV2 += mV1; + mV1 = RotateLeft(mV1, 17); + mV1 ^= mV2; + mV2 = RotateLeft(mV2, 32); + } + + uint64_t mV0, mV1, mV2, mV3; + }; +}; + +} /* namespace mozilla */ +#endif /* __cplusplus */ + +#endif /* mozilla_HashFunctions_h */ diff --git a/mfbt/IndexSequence.h b/mfbt/IndexSequence.h new file mode 100644 index 000000000..1ccace026 --- /dev/null +++ b/mfbt/IndexSequence.h @@ -0,0 +1,143 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* A utility for expanding a tuple into a variadic argument list. + * Based on std::index_sequence. */ + +/** + * Example usage: + * + * Problem: + * + * You have a variadic function Foo: + * + * template <typename... Args> void Foo(Args...); + * + * And a variadic function Bar, which contains a tuple: + * + * template <typename... Args> + * void Bar() { + * // ... + * Tuple<Args...> t; + * } + * + * And inside Bar, you want to call Foo with the elements of the tuple as + * arguments to Foo. + * + * You want to write: + * + * Foo(Get<0>(t), Get<1>(t), ..., Get<N>(t)) + * + * but you can't literally write that, because N is different for different + * instantiations of Bar. + * + * Solution: + * + * Write a helper function which takes the tuple, and an index sequence + * containing indices corresponding to the tuple indices. + * + * template <typename... Args, size_t... Indices> + * void Helper(const Tuple<Args...>& t, IndexSequence<Indices>) + * { + * Foo(Get<Indices>(t)...); + * } + * + * Assuming 'Indices...' are 0, 1, ..., N - 1, where N is the size of the + * tuple, pack expansion will expand the pack 'Get<Indices>(t)...' to + * 'Get<0>(t), Get<1>(t), ..., Get<N>(t)'. + * + * Finally, call the helper, creating the index sequence to pass in like so: + * + * template <typename... Args> + * void Bar() { + * // ... + * Tuple<Args...> t; + * Helper(t, typename IndexSequenceFor<Args...>::Type()); + * } + */ + +#ifndef mozilla_IndexSequence_h +#define mozilla_IndexSequence_h + +#include "mozilla/Attributes.h" + +#include <stddef.h> + +namespace mozilla { + +/** + * Represents a compile-time sequence of integer indices. + */ +template<size_t... Indices> +struct IndexSequence +{ + static constexpr size_t Size() { return sizeof...(Indices); } +}; + +namespace detail { + +// Helpers used by MakeIndexSequence. + +template<size_t... Indices> +struct IndexTuple +{ + typedef IndexTuple<Indices..., sizeof...(Indices)> Next; +}; + +// Builds IndexTuple<0, 1, ..., N - 1>. +template<size_t N> +struct BuildIndexTuple +{ + typedef typename BuildIndexTuple<N - 1>::Type::Next Type; +}; + +template<> +struct BuildIndexTuple<0> +{ + typedef IndexTuple<> Type; +}; + +template<size_t N, typename IndexTuple> +struct MakeIndexSequenceImpl; + +template<size_t N, size_t... Indices> +struct MakeIndexSequenceImpl<N, IndexTuple<Indices...>> +{ + typedef IndexSequence<Indices...> Type; +}; + +} // namespace detail + +/** + * A utility for building an IndexSequence of consecutive indices. + * MakeIndexSequence<N>::Type evaluates to IndexSequence<0, 1, .., N - 1>. + * Note: unlike std::make_index_sequence, this is not an alias template + * to work around bugs in MSVC 2013. + */ +template<size_t N> +struct MakeIndexSequence +{ + typedef typename detail::MakeIndexSequenceImpl<N, + typename detail::BuildIndexTuple<N>::Type>::Type Type; +}; + +/** + * A utility for building an IndexSequence of consecutive indices + * corresponding to a variadic argument list. + * IndexSequenceFor<Types...> evaluates to IndexSequence<0, 1, ..., N - 1> + * where N is the number of types in Types. + * Note: unlike std::index_sequence_for, this is not an alias template + * to work around bugs in MSVC 2013. + */ +template<typename... Types> +struct IndexSequenceFor +{ + typedef typename MakeIndexSequence<sizeof...(Types)>::Type Type; +}; + +} // namespace mozilla + +#endif /* mozilla_IndexSequence_h */ diff --git a/mfbt/IntegerPrintfMacros.h b/mfbt/IntegerPrintfMacros.h new file mode 100644 index 000000000..c534a0ba2 --- /dev/null +++ b/mfbt/IntegerPrintfMacros.h @@ -0,0 +1,52 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Implements the C99 <inttypes.h> interface. */ + +#ifndef mozilla_IntegerPrintfMacros_h_ +#define mozilla_IntegerPrintfMacros_h_ + +/* + * These macros should not be used with the NSPR printf-like functions or their + * users, e.g. mozilla/Logging.h. If you need to use NSPR's facilities, see the + * comment on supported formats at the top of nsprpub/pr/include/prprf.h. + */ + +/* + * scanf is a footgun: if the input number exceeds the bounds of the target + * type, behavior is undefined (in the compiler sense: that is, this code + * could overwrite your hard drive with zeroes): + * + * uint8_t u; + * sscanf("256", "%" SCNu8, &u); // BAD + * + * For this reason, *never* use the SCN* macros provided by this header! + */ + +#include <inttypes.h> + +/* + * Fix up Android's broken [u]intptr_t inttype macros. Android's PRI*PTR + * macros are defined as "ld", but sizeof(long) is 8 and sizeof(intptr_t) + * is 4 on 32-bit Android. TestTypeTraits.cpp asserts that these new macro + * definitions match the actual type sizes seen at compile time. + */ +#if defined(ANDROID) && !defined(__LP64__) +# undef PRIdPTR /* intptr_t */ +# define PRIdPTR "d" /* intptr_t */ +# undef PRIiPTR /* intptr_t */ +# define PRIiPTR "i" /* intptr_t */ +# undef PRIoPTR /* uintptr_t */ +# define PRIoPTR "o" /* uintptr_t */ +# undef PRIuPTR /* uintptr_t */ +# define PRIuPTR "u" /* uintptr_t */ +# undef PRIxPTR /* uintptr_t */ +# define PRIxPTR "x" /* uintptr_t */ +# undef PRIXPTR /* uintptr_t */ +# define PRIXPTR "X" /* uintptr_t */ +#endif + +#endif /* mozilla_IntegerPrintfMacros_h_ */ diff --git a/mfbt/IntegerRange.h b/mfbt/IntegerRange.h new file mode 100644 index 000000000..8d5d2e4d6 --- /dev/null +++ b/mfbt/IntegerRange.h @@ -0,0 +1,181 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Iterator over ranges of integers */ + +#ifndef mozilla_IntegerRange_h +#define mozilla_IntegerRange_h + +#include "mozilla/Assertions.h" +#include "mozilla/ReverseIterator.h" +#include "mozilla/TypeTraits.h" + +namespace mozilla { + +namespace detail { + +template<typename IntTypeT> +class IntegerIterator +{ +public: + template<typename IntType> + explicit IntegerIterator(IntType aCurrent) + : mCurrent(aCurrent) { } + + template<typename IntType> + explicit IntegerIterator(const IntegerIterator<IntType>& aOther) + : mCurrent(aOther.mCurrent) { } + + IntTypeT operator*() const { return mCurrent; } + + /* Increment and decrement operators */ + + IntegerIterator& operator++() { ++mCurrent; return *this; } + IntegerIterator& operator--() { --mCurrent; return *this; } + IntegerIterator operator++(int) { auto ret = *this; ++mCurrent; return ret; } + IntegerIterator operator--(int) { auto ret = *this; --mCurrent; return ret; } + + /* Comparison operators */ + + template<typename IntType1, typename IntType2> + friend bool operator==(const IntegerIterator<IntType1>& aIter1, + const IntegerIterator<IntType2>& aIter2); + template<typename IntType1, typename IntType2> + friend bool operator!=(const IntegerIterator<IntType1>& aIter1, + const IntegerIterator<IntType2>& aIter2); + template<typename IntType1, typename IntType2> + friend bool operator<(const IntegerIterator<IntType1>& aIter1, + const IntegerIterator<IntType2>& aIter2); + template<typename IntType1, typename IntType2> + friend bool operator<=(const IntegerIterator<IntType1>& aIter1, + const IntegerIterator<IntType2>& aIter2); + template<typename IntType1, typename IntType2> + friend bool operator>(const IntegerIterator<IntType1>& aIter1, + const IntegerIterator<IntType2>& aIter2); + template<typename IntType1, typename IntType2> + friend bool operator>=(const IntegerIterator<IntType1>& aIter1, + const IntegerIterator<IntType2>& aIter2); + +private: + IntTypeT mCurrent; +}; + +template<typename IntType1, typename IntType2> +bool operator==(const IntegerIterator<IntType1>& aIter1, + const IntegerIterator<IntType2>& aIter2) +{ + return aIter1.mCurrent == aIter2.mCurrent; +} + +template<typename IntType1, typename IntType2> +bool operator!=(const IntegerIterator<IntType1>& aIter1, + const IntegerIterator<IntType2>& aIter2) +{ + return aIter1.mCurrent != aIter2.mCurrent; +} + +template<typename IntType1, typename IntType2> +bool operator<(const IntegerIterator<IntType1>& aIter1, + const IntegerIterator<IntType2>& aIter2) +{ + return aIter1.mCurrent < aIter2.mCurrent; +} + +template<typename IntType1, typename IntType2> +bool operator<=(const IntegerIterator<IntType1>& aIter1, + const IntegerIterator<IntType2>& aIter2) +{ + return aIter1.mCurrent <= aIter2.mCurrent; +} + +template<typename IntType1, typename IntType2> +bool operator>(const IntegerIterator<IntType1>& aIter1, + const IntegerIterator<IntType2>& aIter2) +{ + return aIter1.mCurrent > aIter2.mCurrent; +} + +template<typename IntType1, typename IntType2> +bool operator>=(const IntegerIterator<IntType1>& aIter1, + const IntegerIterator<IntType2>& aIter2) +{ + return aIter1.mCurrent >= aIter2.mCurrent; +} + +template<typename IntTypeT> +class IntegerRange +{ +public: + typedef IntegerIterator<IntTypeT> iterator; + typedef IntegerIterator<IntTypeT> const_iterator; + typedef ReverseIterator<IntegerIterator<IntTypeT>> reverse_iterator; + typedef ReverseIterator<IntegerIterator<IntTypeT>> const_reverse_iterator; + + template<typename IntType> + explicit IntegerRange(IntType aEnd) + : mBegin(0), mEnd(aEnd) { } + + template<typename IntType1, typename IntType2> + IntegerRange(IntType1 aBegin, IntType2 aEnd) + : mBegin(aBegin), mEnd(aEnd) { } + + iterator begin() const { return iterator(mBegin); } + const_iterator cbegin() const { return begin(); } + iterator end() const { return iterator(mEnd); } + const_iterator cend() const { return end(); } + reverse_iterator rbegin() const { return reverse_iterator(mEnd); } + const_reverse_iterator crbegin() const { return rbegin(); } + reverse_iterator rend() const { return reverse_iterator(mBegin); } + const_reverse_iterator crend() const { return rend(); } + +private: + IntTypeT mBegin; + IntTypeT mEnd; +}; + +template<typename T, bool = IsUnsigned<T>::value> +struct GeqZero +{ + static bool check(T t) { + return t >= 0; + } +}; + +template<typename T> +struct GeqZero<T, true> +{ + static bool check(T t) { + return true; + } +}; + +} // namespace detail + +template<typename IntType> +detail::IntegerRange<IntType> +MakeRange(IntType aEnd) +{ + static_assert(IsIntegral<IntType>::value, "value must be integral"); + MOZ_ASSERT(detail::GeqZero<IntType>::check(aEnd), + "Should never have negative value here"); + return detail::IntegerRange<IntType>(aEnd); +} + +template<typename IntType1, typename IntType2> +detail::IntegerRange<IntType2> +MakeRange(IntType1 aBegin, IntType2 aEnd) +{ + static_assert(IsIntegral<IntType1>::value && IsIntegral<IntType2>::value, + "values must both be integral"); + static_assert(IsSigned<IntType1>::value == IsSigned<IntType2>::value, + "signed/unsigned mismatch"); + MOZ_ASSERT(aEnd >= aBegin, "End value should be larger than begin value"); + return detail::IntegerRange<IntType2>(aBegin, aEnd); +} + +} // namespace mozilla + +#endif // mozilla_IntegerRange_h diff --git a/mfbt/IntegerTypeTraits.h b/mfbt/IntegerTypeTraits.h new file mode 100644 index 000000000..6144d2084 --- /dev/null +++ b/mfbt/IntegerTypeTraits.h @@ -0,0 +1,143 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Helpers to manipulate integer types that don't fit in TypeTraits.h */ + +#ifndef mozilla_IntegerTypeTraits_h +#define mozilla_IntegerTypeTraits_h + +#include "mozilla/TypeTraits.h" +#include <stdint.h> + +namespace mozilla { + +namespace detail { + +/** + * StdintTypeForSizeAndSignedness returns the stdint integer type + * of given size (can be 1, 2, 4 or 8) and given signedness + * (false means unsigned, true means signed). + */ +template<size_t Size, bool Signedness> +struct StdintTypeForSizeAndSignedness; + +template<> +struct StdintTypeForSizeAndSignedness<1, true> +{ + typedef int8_t Type; +}; + +template<> +struct StdintTypeForSizeAndSignedness<1, false> +{ + typedef uint8_t Type; +}; + +template<> +struct StdintTypeForSizeAndSignedness<2, true> +{ + typedef int16_t Type; +}; + +template<> +struct StdintTypeForSizeAndSignedness<2, false> +{ + typedef uint16_t Type; +}; + +template<> +struct StdintTypeForSizeAndSignedness<4, true> +{ + typedef int32_t Type; +}; + +template<> +struct StdintTypeForSizeAndSignedness<4, false> +{ + typedef uint32_t Type; +}; + +template<> +struct StdintTypeForSizeAndSignedness<8, true> +{ + typedef int64_t Type; +}; + +template<> +struct StdintTypeForSizeAndSignedness<8, false> +{ + typedef uint64_t Type; +}; + +} // namespace detail + +template<size_t Size> +struct UnsignedStdintTypeForSize + : detail::StdintTypeForSizeAndSignedness<Size, false> +{}; + +template<size_t Size> +struct SignedStdintTypeForSize + : detail::StdintTypeForSizeAndSignedness<Size, true> +{}; + +template<typename IntegerType> +struct PositionOfSignBit +{ + static_assert(IsIntegral<IntegerType>::value, + "PositionOfSignBit is only for integral types"); + // 8 here should be CHAR_BIT from limits.h, but the world has moved on. + static const size_t value = 8 * sizeof(IntegerType) - 1; +}; + +/** + * MinValue returns the minimum value of the given integer type as a + * compile-time constant, which std::numeric_limits<IntegerType>::min() + * cannot do in c++98. + */ +template<typename IntegerType> +struct MinValue +{ +private: + static_assert(IsIntegral<IntegerType>::value, + "MinValue is only for integral types"); + + typedef typename MakeUnsigned<IntegerType>::Type UnsignedIntegerType; + static const size_t PosOfSignBit = PositionOfSignBit<IntegerType>::value; + +public: + // Bitwise ops may return a larger type, that's why we cast explicitly. + // In C++, left bit shifts on signed values is undefined by the standard + // unless the shifted value is representable. + // Notice that signed-to-unsigned conversions are always well-defined in + // the standard as the value congruent to 2**n, as expected. By contrast, + // unsigned-to-signed is only well-defined if the value is representable. + static const IntegerType value = + IsSigned<IntegerType>::value + ? IntegerType(UnsignedIntegerType(1) << PosOfSignBit) + : IntegerType(0); +}; + +/** + * MaxValue returns the maximum value of the given integer type as a + * compile-time constant, which std::numeric_limits<IntegerType>::max() + * cannot do in c++98. + */ +template<typename IntegerType> +struct MaxValue +{ + static_assert(IsIntegral<IntegerType>::value, + "MaxValue is only for integral types"); + + // Tricksy, but covered by the CheckedInt unit test. + // Relies on the type of MinValue<IntegerType>::value + // being IntegerType. + static const IntegerType value = ~MinValue<IntegerType>::value; +}; + +} // namespace mozilla + +#endif // mozilla_IntegerTypeTraits_h diff --git a/mfbt/JSONWriter.cpp b/mfbt/JSONWriter.cpp new file mode 100644 index 000000000..fc4897934 --- /dev/null +++ b/mfbt/JSONWriter.cpp @@ -0,0 +1,49 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/JSONWriter.h" + +namespace mozilla { +namespace detail { + +// The chars with non-'___' entries in this table are those that can be +// represented with a two-char escape sequence. The value is the second char in +// the sequence, that which follows the initial backslash. +#define ___ 0 +const char gTwoCharEscapes[256] = { +/* 0 1 2 3 4 5 6 7 8 9 */ +/* 0+ */ ___, ___, ___, ___, ___, ___, ___, ___, 'b', 't', +/* 10+ */ 'n', ___, 'f', 'r', ___, ___, ___, ___, ___, ___, +/* 20+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 30+ */ ___, ___, ___, ___, '"', ___, ___, ___, ___, ___, +/* 40+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 50+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 60+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 70+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 80+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 90+ */ ___, ___,'\\', ___, ___, ___, ___, ___, ___, ___, +/* 100+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 110+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 120+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 130+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 140+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 150+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 160+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 170+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 180+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 190+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 200+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 210+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 220+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 230+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 240+ */ ___, ___, ___, ___, ___, ___, ___, ___, ___, ___, +/* 250+ */ ___, ___, ___, ___, ___, ___ +}; +#undef ___ + +} // namespace detail +} // namespace mozilla + diff --git a/mfbt/JSONWriter.h b/mfbt/JSONWriter.h new file mode 100644 index 000000000..7d44dc7f5 --- /dev/null +++ b/mfbt/JSONWriter.h @@ -0,0 +1,460 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* A JSON pretty-printer class. */ + +// A typical JSON-writing library requires you to first build up a data +// structure that represents a JSON object and then serialize it (to file, or +// somewhere else). This approach makes for a clean API, but building the data +// structure takes up memory. Sometimes that isn't desirable, such as when the +// JSON data is produced for memory reporting. +// +// The JSONWriter class instead allows JSON data to be written out +// incrementally without building up large data structures. +// +// The API is slightly uglier than you would see in a typical JSON-writing +// library, but still fairly easy to use. It's possible to generate invalid +// JSON with JSONWriter, but typically the most basic testing will identify any +// such problems. +// +// Similarly, there are no RAII facilities for automatically closing objects +// and arrays. These would be nice if you are generating all your code within +// nested functions, but in other cases you'd have to maintain an explicit +// stack of RAII objects and manually unwind it, which is no better than just +// calling "end" functions. Furthermore, the consequences of forgetting to +// close an object or array are obvious and, again, will be identified via +// basic testing, unlike other cases where RAII is typically used (e.g. smart +// pointers) and the consequences of defects are more subtle. +// +// Importantly, the class does solve the two hard problems of JSON +// pretty-printing, which are (a) correctly escaping strings, and (b) adding +// appropriate indentation and commas between items. +// +// By default, every property is placed on its own line. However, it is +// possible to request that objects and arrays be placed entirely on a single +// line, which can reduce output size significantly in some cases. +// +// Strings used (for property names and string property values) are |const +// char*| throughout, and can be ASCII or UTF-8. +// +// EXAMPLE +// ------- +// Assume that |MyWriteFunc| is a class that implements |JSONWriteFunc|. The +// following code: +// +// JSONWriter w(MakeUnique<MyWriteFunc>()); +// w.Start(); +// { +// w.NullProperty("null"); +// w.BoolProperty("bool", true); +// w.IntProperty("int", 1); +// w.StartArrayProperty("array"); +// { +// w.StringElement("string"); +// w.StartObjectElement(); +// { +// w.DoubleProperty("double", 3.4); +// w.StartArrayProperty("single-line array", w.SingleLineStyle); +// { +// w.IntElement(1); +// w.StartObjectElement(); // SingleLineStyle is inherited from +// w.EndObjectElement(); // above for this collection +// } +// w.EndArray(); +// } +// w.EndObjectElement(); +// } +// w.EndArrayProperty(); +// } +// w.End(); +// +// will produce pretty-printed output for the following JSON object: +// +// { +// "null": null, +// "bool": true, +// "int": 1, +// "array": [ +// "string", +// { +// "double": 3.4, +// "single-line array": [1, {}] +// } +// ] +// } +// +// The nesting in the example code is obviously optional, but can aid +// readability. + +#ifndef mozilla_JSONWriter_h +#define mozilla_JSONWriter_h + +#include "mozilla/double-conversion.h" +#include "mozilla/IntegerPrintfMacros.h" +#include "mozilla/PodOperations.h" +#include "mozilla/Sprintf.h" +#include "mozilla/UniquePtr.h" +#include "mozilla/Vector.h" + +#include <stdio.h> + +namespace mozilla { + +// A quasi-functor for JSONWriter. We don't use a true functor because that +// requires templatizing JSONWriter, and the templatization seeps to lots of +// places we don't want it to. +class JSONWriteFunc +{ +public: + virtual void Write(const char* aStr) = 0; + virtual ~JSONWriteFunc() {} +}; + +// Ideally this would be within |EscapedString| but when compiling with GCC +// on Linux that caused link errors, whereas this formulation didn't. +namespace detail { +extern MFBT_DATA const char gTwoCharEscapes[256]; +} // namespace detail + +class JSONWriter +{ + // From http://www.ietf.org/rfc/rfc4627.txt: + // + // "All Unicode characters may be placed within the quotation marks except + // for the characters that must be escaped: quotation mark, reverse + // solidus, and the control characters (U+0000 through U+001F)." + // + // This implementation uses two-char escape sequences where possible, namely: + // + // \", \\, \b, \f, \n, \r, \t + // + // All control characters not in the above list are represented with a + // six-char escape sequence, e.g. '\u000b' (a.k.a. '\v'). + // + class EscapedString + { + // Only one of |mUnownedStr| and |mOwnedStr| are ever non-null. |mIsOwned| + // indicates which one is in use. They're not within a union because that + // wouldn't work with UniquePtr. + bool mIsOwned; + const char* mUnownedStr; + UniquePtr<char[]> mOwnedStr; + + void SanityCheck() const + { + MOZ_ASSERT_IF( mIsOwned, mOwnedStr.get() && !mUnownedStr); + MOZ_ASSERT_IF(!mIsOwned, !mOwnedStr.get() && mUnownedStr); + } + + static char hexDigitToAsciiChar(uint8_t u) + { + u = u & 0xf; + return u < 10 ? '0' + u : 'a' + (u - 10); + } + + public: + explicit EscapedString(const char* aStr) + : mUnownedStr(nullptr) + , mOwnedStr(nullptr) + { + const char* p; + + // First, see if we need to modify the string. + size_t nExtra = 0; + p = aStr; + while (true) { + uint8_t u = *p; // ensure it can't be interpreted as negative + if (u == 0) { + break; + } + if (detail::gTwoCharEscapes[u]) { + nExtra += 1; + } else if (u <= 0x1f) { + nExtra += 5; + } + p++; + } + + if (nExtra == 0) { + // No escapes needed. Easy. + mIsOwned = false; + mUnownedStr = aStr; + return; + } + + // Escapes are needed. We'll create a new string. + mIsOwned = true; + size_t len = (p - aStr) + nExtra; + mOwnedStr = MakeUnique<char[]>(len + 1); + + p = aStr; + size_t i = 0; + + while (true) { + uint8_t u = *p; // ensure it can't be interpreted as negative + if (u == 0) { + mOwnedStr[i] = 0; + break; + } + if (detail::gTwoCharEscapes[u]) { + mOwnedStr[i++] = '\\'; + mOwnedStr[i++] = detail::gTwoCharEscapes[u]; + } else if (u <= 0x1f) { + mOwnedStr[i++] = '\\'; + mOwnedStr[i++] = 'u'; + mOwnedStr[i++] = '0'; + mOwnedStr[i++] = '0'; + mOwnedStr[i++] = hexDigitToAsciiChar((u & 0x00f0) >> 4); + mOwnedStr[i++] = hexDigitToAsciiChar(u & 0x000f); + } else { + mOwnedStr[i++] = u; + } + p++; + } + } + + ~EscapedString() + { + SanityCheck(); + } + + const char* get() const + { + SanityCheck(); + return mIsOwned ? mOwnedStr.get() : mUnownedStr; + } + }; + +public: + // Collections (objects and arrays) are printed in a multi-line style by + // default. This can be changed to a single-line style if SingleLineStyle is + // specified. If a collection is printed in single-line style, every nested + // collection within it is also printed in single-line style, even if + // multi-line style is requested. + enum CollectionStyle { + MultiLineStyle, // the default + SingleLineStyle + }; + +protected: + const UniquePtr<JSONWriteFunc> mWriter; + Vector<bool, 8> mNeedComma; // do we need a comma at depth N? + Vector<bool, 8> mNeedNewlines; // do we need newlines at depth N? + size_t mDepth; // the current nesting depth + + void Indent() + { + for (size_t i = 0; i < mDepth; i++) { + mWriter->Write(" "); + } + } + + // Adds whatever is necessary (maybe a comma, and then a newline and + // whitespace) to separate an item (property or element) from what's come + // before. + void Separator() + { + if (mNeedComma[mDepth]) { + mWriter->Write(","); + } + if (mDepth > 0 && mNeedNewlines[mDepth]) { + mWriter->Write("\n"); + Indent(); + } else if (mNeedComma[mDepth]) { + mWriter->Write(" "); + } + } + + void PropertyNameAndColon(const char* aName) + { + EscapedString escapedName(aName); + mWriter->Write("\""); + mWriter->Write(escapedName.get()); + mWriter->Write("\": "); + } + + void Scalar(const char* aMaybePropertyName, const char* aStringValue) + { + Separator(); + if (aMaybePropertyName) { + PropertyNameAndColon(aMaybePropertyName); + } + mWriter->Write(aStringValue); + mNeedComma[mDepth] = true; + } + + void QuotedScalar(const char* aMaybePropertyName, const char* aStringValue) + { + Separator(); + if (aMaybePropertyName) { + PropertyNameAndColon(aMaybePropertyName); + } + mWriter->Write("\""); + mWriter->Write(aStringValue); + mWriter->Write("\""); + mNeedComma[mDepth] = true; + } + + void NewVectorEntries() + { + // If these tiny allocations OOM we might as well just crash because we + // must be in serious memory trouble. + MOZ_RELEASE_ASSERT(mNeedComma.resizeUninitialized(mDepth + 1)); + MOZ_RELEASE_ASSERT(mNeedNewlines.resizeUninitialized(mDepth + 1)); + mNeedComma[mDepth] = false; + mNeedNewlines[mDepth] = true; + } + + void StartCollection(const char* aMaybePropertyName, const char* aStartChar, + CollectionStyle aStyle = MultiLineStyle) + { + Separator(); + if (aMaybePropertyName) { + mWriter->Write("\""); + mWriter->Write(aMaybePropertyName); + mWriter->Write("\": "); + } + mWriter->Write(aStartChar); + mNeedComma[mDepth] = true; + mDepth++; + NewVectorEntries(); + mNeedNewlines[mDepth] = + mNeedNewlines[mDepth - 1] && aStyle == MultiLineStyle; + } + + // Adds the whitespace and closing char necessary to end a collection. + void EndCollection(const char* aEndChar) + { + if (mNeedNewlines[mDepth]) { + mWriter->Write("\n"); + mDepth--; + Indent(); + } else { + mDepth--; + } + mWriter->Write(aEndChar); + } + +public: + explicit JSONWriter(UniquePtr<JSONWriteFunc> aWriter) + : mWriter(Move(aWriter)) + , mNeedComma() + , mNeedNewlines() + , mDepth(0) + { + NewVectorEntries(); + } + + // Returns the JSONWriteFunc passed in at creation, for temporary use. The + // JSONWriter object still owns the JSONWriteFunc. + JSONWriteFunc* WriteFunc() const { return mWriter.get(); } + + // For all the following functions, the "Prints:" comment indicates what the + // basic output looks like. However, it doesn't indicate the whitespace and + // trailing commas, which are automatically added as required. + // + // All property names and string properties are escaped as necessary. + + // Prints: { + void Start(CollectionStyle aStyle = MultiLineStyle) + { + StartCollection(nullptr, "{", aStyle); + } + + // Prints: } + void End() { EndCollection("}\n"); } + + // Prints: "<aName>": null + void NullProperty(const char* aName) + { + Scalar(aName, "null"); + } + + // Prints: null + void NullElement() { NullProperty(nullptr); } + + // Prints: "<aName>": <aBool> + void BoolProperty(const char* aName, bool aBool) + { + Scalar(aName, aBool ? "true" : "false"); + } + + // Prints: <aBool> + void BoolElement(bool aBool) { BoolProperty(nullptr, aBool); } + + // Prints: "<aName>": <aInt> + void IntProperty(const char* aName, int64_t aInt) + { + char buf[64]; + SprintfLiteral(buf, "%" PRId64, aInt); + Scalar(aName, buf); + } + + // Prints: <aInt> + void IntElement(int64_t aInt) { IntProperty(nullptr, aInt); } + + // Prints: "<aName>": <aDouble> + void DoubleProperty(const char* aName, double aDouble) + { + static const size_t buflen = 64; + char buf[buflen]; + const double_conversion::DoubleToStringConverter &converter = + double_conversion::DoubleToStringConverter::EcmaScriptConverter(); + double_conversion::StringBuilder builder(buf, buflen); + converter.ToShortest(aDouble, &builder); + Scalar(aName, builder.Finalize()); + } + + // Prints: <aDouble> + void DoubleElement(double aDouble) { DoubleProperty(nullptr, aDouble); } + + // Prints: "<aName>": "<aStr>" + void StringProperty(const char* aName, const char* aStr) + { + EscapedString escapedStr(aStr); + QuotedScalar(aName, escapedStr.get()); + } + + // Prints: "<aStr>" + void StringElement(const char* aStr) { StringProperty(nullptr, aStr); } + + // Prints: "<aName>": [ + void StartArrayProperty(const char* aName, + CollectionStyle aStyle = MultiLineStyle) + { + StartCollection(aName, "[", aStyle); + } + + // Prints: [ + void StartArrayElement(CollectionStyle aStyle = MultiLineStyle) + { + StartArrayProperty(nullptr, aStyle); + } + + // Prints: ] + void EndArray() { EndCollection("]"); } + + // Prints: "<aName>": { + void StartObjectProperty(const char* aName, + CollectionStyle aStyle = MultiLineStyle) + { + StartCollection(aName, "{", aStyle); + } + + // Prints: { + void StartObjectElement(CollectionStyle aStyle = MultiLineStyle) + { + StartObjectProperty(nullptr, aStyle); + } + + // Prints: } + void EndObject() { EndCollection("}"); } +}; + +} // namespace mozilla + +#endif /* mozilla_JSONWriter_h */ + diff --git a/mfbt/Likely.h b/mfbt/Likely.h new file mode 100644 index 000000000..4f2160929 --- /dev/null +++ b/mfbt/Likely.h @@ -0,0 +1,23 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* + * MOZ_LIKELY and MOZ_UNLIKELY macros to hint to the compiler how a + * boolean predicate should be branch-predicted. + */ + +#ifndef mozilla_Likely_h +#define mozilla_Likely_h + +#if defined(__clang__) || defined(__GNUC__) +# define MOZ_LIKELY(x) (__builtin_expect(!!(x), 1)) +# define MOZ_UNLIKELY(x) (__builtin_expect(!!(x), 0)) +#else +# define MOZ_LIKELY(x) (!!(x)) +# define MOZ_UNLIKELY(x) (!!(x)) +#endif + +#endif /* mozilla_Likely_h */ diff --git a/mfbt/LinkedList.h b/mfbt/LinkedList.h new file mode 100644 index 000000000..6e14aa162 --- /dev/null +++ b/mfbt/LinkedList.h @@ -0,0 +1,659 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* A type-safe doubly-linked list class. */ + +/* + * The classes LinkedList<T> and LinkedListElement<T> together form a + * convenient, type-safe doubly-linked list implementation. + * + * The class T which will be inserted into the linked list must inherit from + * LinkedListElement<T>. A given object may be in only one linked list at a + * time. + * + * A LinkedListElement automatically removes itself from the list upon + * destruction, and a LinkedList will fatally assert in debug builds if it's + * non-empty when it's destructed. + * + * For example, you might use LinkedList in a simple observer list class as + * follows. + * + * class Observer : public LinkedListElement<Observer> + * { + * public: + * void observe(char* aTopic) { ... } + * }; + * + * class ObserverContainer + * { + * private: + * LinkedList<Observer> list; + * + * public: + * void addObserver(Observer* aObserver) + * { + * // Will assert if |aObserver| is part of another list. + * list.insertBack(aObserver); + * } + * + * void removeObserver(Observer* aObserver) + * { + * // Will assert if |aObserver| is not part of some list. + * aObserver.remove(); + * // Or, will assert if |aObserver| is not part of |list| specifically. + * // aObserver.removeFrom(list); + * } + * + * void notifyObservers(char* aTopic) + * { + * for (Observer* o = list.getFirst(); o != nullptr; o = o->getNext()) { + * o->observe(aTopic); + * } + * } + * }; + * + * Additionally, the class AutoCleanLinkedList<T> is a LinkedList<T> that will + * remove and delete each element still within itself upon destruction. Note + * that because each element is deleted, elements must have been allocated + * using |new|. + */ + +#ifndef mozilla_LinkedList_h +#define mozilla_LinkedList_h + +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" +#include "mozilla/MemoryReporting.h" +#include "mozilla/Move.h" +#include "mozilla/RefPtr.h" + +#ifdef __cplusplus + +namespace mozilla { + +template<typename T> +class LinkedListElement; + +namespace detail { + +/** + * LinkedList supports refcounted elements using this adapter class. Clients + * using LinkedList<RefPtr<T>> will get a data structure that holds a strong + * reference to T as long as T is in the list. + */ +template<typename T> +struct LinkedListElementTraits +{ + typedef T* RawType; + typedef const T* ConstRawType; + typedef T* ClientType; + typedef const T* ConstClientType; + + // These static methods are called when an element is added to or removed from + // a linked list. It can be used to keep track ownership in lists that are + // supposed to own their elements. If elements are transferred from one list + // to another, no enter or exit calls happen since the elements still belong + // to a list. + static void enterList(LinkedListElement<T>* elt) {} + static void exitList(LinkedListElement<T>* elt) {} +}; + +template<typename T> +struct LinkedListElementTraits<RefPtr<T>> +{ + typedef T* RawType; + typedef const T* ConstRawType; + typedef RefPtr<T> ClientType; + typedef RefPtr<const T> ConstClientType; + + static void enterList(LinkedListElement<RefPtr<T>>* elt) { elt->asT()->AddRef(); } + static void exitList(LinkedListElement<RefPtr<T>>* elt) { elt->asT()->Release(); } +}; + +} /* namespace detail */ + +template<typename T> +class LinkedList; + +template<typename T> +class LinkedListElement +{ + typedef typename detail::LinkedListElementTraits<T> Traits; + typedef typename Traits::RawType RawType; + typedef typename Traits::ConstRawType ConstRawType; + typedef typename Traits::ClientType ClientType; + typedef typename Traits::ConstClientType ConstClientType; + + /* + * It's convenient that we return nullptr when getNext() or getPrevious() + * hits the end of the list, but doing so costs an extra word of storage in + * each linked list node (to keep track of whether |this| is the sentinel + * node) and a branch on this value in getNext/getPrevious. + * + * We could get rid of the extra word of storage by shoving the "is + * sentinel" bit into one of the pointers, although this would, of course, + * have performance implications of its own. + * + * But the goal here isn't to win an award for the fastest or slimmest + * linked list; rather, we want a *convenient* linked list. So we won't + * waste time guessing which micro-optimization strategy is best. + * + * + * Speaking of unnecessary work, it's worth addressing here why we wrote + * mozilla::LinkedList in the first place, instead of using stl::list. + * + * The key difference between mozilla::LinkedList and stl::list is that + * mozilla::LinkedList stores the mPrev/mNext pointers in the object itself, + * while stl::list stores the mPrev/mNext pointers in a list element which + * itself points to the object being stored. + * + * mozilla::LinkedList's approach makes it harder to store an object in more + * than one list. But the upside is that you can call next() / prev() / + * remove() directly on the object. With stl::list, you'd need to store a + * pointer to its iterator in the object in order to accomplish this. Not + * only would this waste space, but you'd have to remember to update that + * pointer every time you added or removed the object from a list. + * + * In-place, constant-time removal is a killer feature of doubly-linked + * lists, and supporting this painlessly was a key design criterion. + */ + +private: + LinkedListElement* mNext; + LinkedListElement* mPrev; + const bool mIsSentinel; + +public: + LinkedListElement() + : mNext(this), + mPrev(this), + mIsSentinel(false) + { } + + /* + * Moves |aOther| into |*this|. If |aOther| is already in a list, then + * |aOther| is removed from the list and replaced by |*this|. + */ + LinkedListElement(LinkedListElement<T>&& aOther) + : mIsSentinel(aOther.mIsSentinel) + { + adjustLinkForMove(Move(aOther)); + } + + LinkedListElement& operator=(LinkedListElement<T>&& aOther) + { + MOZ_ASSERT(mIsSentinel == aOther.mIsSentinel, "Mismatch NodeKind!"); + MOZ_ASSERT(!isInList(), + "Assigning to an element in a list messes up that list!"); + adjustLinkForMove(Move(aOther)); + return *this; + } + + ~LinkedListElement() + { + if (!mIsSentinel && isInList()) { + remove(); + } + } + + /* + * Get the next element in the list, or nullptr if this is the last element + * in the list. + */ + RawType getNext() { return mNext->asT(); } + ConstRawType getNext() const { return mNext->asT(); } + + /* + * Get the previous element in the list, or nullptr if this is the first + * element in the list. + */ + RawType getPrevious() { return mPrev->asT(); } + ConstRawType getPrevious() const { return mPrev->asT(); } + + /* + * Insert aElem after this element in the list. |this| must be part of a + * linked list when you call setNext(); otherwise, this method will assert. + */ + void setNext(RawType aElem) + { + MOZ_ASSERT(isInList()); + setNextUnsafe(aElem); + } + + /* + * Insert aElem before this element in the list. |this| must be part of a + * linked list when you call setPrevious(); otherwise, this method will + * assert. + */ + void setPrevious(RawType aElem) + { + MOZ_ASSERT(isInList()); + setPreviousUnsafe(aElem); + } + + /* + * Remove this element from the list which contains it. If this element is + * not currently part of a linked list, this method asserts. + */ + void remove() + { + MOZ_ASSERT(isInList()); + + mPrev->mNext = mNext; + mNext->mPrev = mPrev; + mNext = this; + mPrev = this; + + Traits::exitList(this); + } + + /* + * Remove this element from the list containing it. Returns a pointer to the + * element that follows this element (before it was removed). This method + * asserts if the element does not belong to a list. + */ + ClientType removeAndGetNext() + { + ClientType r = getNext(); + remove(); + return r; + } + + /* + * Remove this element from the list containing it. Returns a pointer to the + * previous element in the containing list (before the removal). This method + * asserts if the element does not belong to a list. + */ + ClientType removeAndGetPrevious() + { + ClientType r = getPrevious(); + remove(); + return r; + } + + /* + * Identical to remove(), but also asserts in debug builds that this element + * is in aList. + */ + void removeFrom(const LinkedList<T>& aList) + { + aList.assertContains(asT()); + remove(); + } + + /* + * Return true if |this| part is of a linked list, and false otherwise. + */ + bool isInList() const + { + MOZ_ASSERT((mNext == this) == (mPrev == this)); + return mNext != this; + } + +private: + friend class LinkedList<T>; + friend struct detail::LinkedListElementTraits<T>; + + enum class NodeKind { + Normal, + Sentinel + }; + + explicit LinkedListElement(NodeKind nodeKind) + : mNext(this), + mPrev(this), + mIsSentinel(nodeKind == NodeKind::Sentinel) + { } + + /* + * Return |this| cast to T* if we're a normal node, or return nullptr if + * we're a sentinel node. + */ + RawType asT() + { + return mIsSentinel ? nullptr : static_cast<RawType>(this); + } + ConstRawType asT() const + { + return mIsSentinel ? nullptr : static_cast<ConstRawType>(this); + } + + /* + * Insert aElem after this element, but don't check that this element is in + * the list. This is called by LinkedList::insertFront(). + */ + void setNextUnsafe(RawType aElem) + { + LinkedListElement *listElem = static_cast<LinkedListElement*>(aElem); + MOZ_ASSERT(!listElem->isInList()); + + listElem->mNext = this->mNext; + listElem->mPrev = this; + this->mNext->mPrev = listElem; + this->mNext = listElem; + + Traits::enterList(aElem); + } + + /* + * Insert aElem before this element, but don't check that this element is in + * the list. This is called by LinkedList::insertBack(). + */ + void setPreviousUnsafe(RawType aElem) + { + LinkedListElement<T>* listElem = static_cast<LinkedListElement<T>*>(aElem); + MOZ_ASSERT(!listElem->isInList()); + + listElem->mNext = this; + listElem->mPrev = this->mPrev; + this->mPrev->mNext = listElem; + this->mPrev = listElem; + + Traits::enterList(aElem); + } + + /* + * Adjust mNext and mPrev for implementing move constructor and move + * assignment. + */ + void adjustLinkForMove(LinkedListElement<T>&& aOther) + { + if (!aOther.isInList()) { + mNext = this; + mPrev = this; + return; + } + + if (!mIsSentinel) { + Traits::enterList(this); + } + + MOZ_ASSERT(aOther.mNext->mPrev == &aOther); + MOZ_ASSERT(aOther.mPrev->mNext == &aOther); + + /* + * Initialize |this| with |aOther|'s mPrev/mNext pointers, and adjust those + * element to point to this one. + */ + mNext = aOther.mNext; + mPrev = aOther.mPrev; + + mNext->mPrev = this; + mPrev->mNext = this; + + /* + * Adjust |aOther| so it doesn't think it's in a list. This makes it + * safely destructable. + */ + aOther.mNext = &aOther; + aOther.mPrev = &aOther; + + if (!mIsSentinel) { + Traits::exitList(&aOther); + } + } + + LinkedListElement& operator=(const LinkedListElement<T>& aOther) = delete; + LinkedListElement(const LinkedListElement<T>& aOther) = delete; +}; + +template<typename T> +class LinkedList +{ +private: + typedef typename detail::LinkedListElementTraits<T> Traits; + typedef typename Traits::RawType RawType; + typedef typename Traits::ConstRawType ConstRawType; + typedef typename Traits::ClientType ClientType; + typedef typename Traits::ConstClientType ConstClientType; + + LinkedListElement<T> sentinel; + +public: + class Iterator { + RawType mCurrent; + + public: + explicit Iterator(RawType aCurrent) : mCurrent(aCurrent) {} + + RawType operator *() const { + return mCurrent; + } + + const Iterator& operator++() { + mCurrent = mCurrent->getNext(); + return *this; + } + + bool operator!=(Iterator& aOther) const { + return mCurrent != aOther.mCurrent; + } + }; + + LinkedList() : sentinel(LinkedListElement<T>::NodeKind::Sentinel) { } + + LinkedList(LinkedList<T>&& aOther) + : sentinel(mozilla::Move(aOther.sentinel)) + { } + + LinkedList& operator=(LinkedList<T>&& aOther) + { + MOZ_ASSERT(isEmpty(), "Assigning to a non-empty list leaks elements in that list!"); + sentinel = mozilla::Move(aOther.sentinel); + return *this; + } + + ~LinkedList() { + MOZ_ASSERT(isEmpty(), + "failing this assertion means this LinkedList's creator is " + "buggy: it should have removed all this list's elements before " + "the list's destruction"); + } + + /* + * Add aElem to the front of the list. + */ + void insertFront(RawType aElem) + { + /* Bypass setNext()'s this->isInList() assertion. */ + sentinel.setNextUnsafe(aElem); + } + + /* + * Add aElem to the back of the list. + */ + void insertBack(RawType aElem) + { + sentinel.setPreviousUnsafe(aElem); + } + + /* + * Get the first element of the list, or nullptr if the list is empty. + */ + RawType getFirst() { return sentinel.getNext(); } + ConstRawType getFirst() const { return sentinel.getNext(); } + + /* + * Get the last element of the list, or nullptr if the list is empty. + */ + RawType getLast() { return sentinel.getPrevious(); } + ConstRawType getLast() const { return sentinel.getPrevious(); } + + /* + * Get and remove the first element of the list. If the list is empty, + * return nullptr. + */ + ClientType popFirst() + { + ClientType ret = sentinel.getNext(); + if (ret) { + static_cast<LinkedListElement<T>*>(RawType(ret))->remove(); + } + return ret; + } + + /* + * Get and remove the last element of the list. If the list is empty, + * return nullptr. + */ + ClientType popLast() + { + ClientType ret = sentinel.getPrevious(); + if (ret) { + static_cast<LinkedListElement<T>*>(RawType(ret))->remove(); + } + return ret; + } + + /* + * Return true if the list is empty, or false otherwise. + */ + bool isEmpty() const + { + return !sentinel.isInList(); + } + + /* + * Remove all the elements from the list. + * + * This runs in time linear to the list's length, because we have to mark + * each element as not in the list. + */ + void clear() + { + while (popFirst()) { + continue; + } + } + + /* + * Allow range-based iteration: + * + * for (MyElementType* elt : myList) { ... } + */ + Iterator begin() { + return Iterator(getFirst()); + } + Iterator end() { + return Iterator(nullptr); + } + + /* + * Measures the memory consumption of the list excluding |this|. Note that + * it only measures the list elements themselves. If the list elements + * contain pointers to other memory blocks, those blocks must be measured + * separately during a subsequent iteration over the list. + */ + size_t sizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const + { + size_t n = 0; + for (const T* t = getFirst(); t; t = t->getNext()) { + n += aMallocSizeOf(t); + } + return n; + } + + /* + * Like sizeOfExcludingThis(), but measures |this| as well. + */ + size_t sizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const + { + return aMallocSizeOf(this) + sizeOfExcludingThis(aMallocSizeOf); + } + + /* + * In a debug build, make sure that the list is sane (no cycles, consistent + * mNext/mPrev pointers, only one sentinel). Has no effect in release builds. + */ + void debugAssertIsSane() const + { +#ifdef DEBUG + const LinkedListElement<T>* slow; + const LinkedListElement<T>* fast1; + const LinkedListElement<T>* fast2; + + /* + * Check for cycles in the forward singly-linked list using the + * tortoise/hare algorithm. + */ + for (slow = sentinel.mNext, + fast1 = sentinel.mNext->mNext, + fast2 = sentinel.mNext->mNext->mNext; + slow != &sentinel && fast1 != &sentinel && fast2 != &sentinel; + slow = slow->mNext, fast1 = fast2->mNext, fast2 = fast1->mNext) { + MOZ_ASSERT(slow != fast1); + MOZ_ASSERT(slow != fast2); + } + + /* Check for cycles in the backward singly-linked list. */ + for (slow = sentinel.mPrev, + fast1 = sentinel.mPrev->mPrev, + fast2 = sentinel.mPrev->mPrev->mPrev; + slow != &sentinel && fast1 != &sentinel && fast2 != &sentinel; + slow = slow->mPrev, fast1 = fast2->mPrev, fast2 = fast1->mPrev) { + MOZ_ASSERT(slow != fast1); + MOZ_ASSERT(slow != fast2); + } + + /* + * Check that |sentinel| is the only node in the list with + * mIsSentinel == true. + */ + for (const LinkedListElement<T>* elem = sentinel.mNext; + elem != &sentinel; + elem = elem->mNext) { + MOZ_ASSERT(!elem->mIsSentinel); + } + + /* Check that the mNext/mPrev pointers match up. */ + const LinkedListElement<T>* prev = &sentinel; + const LinkedListElement<T>* cur = sentinel.mNext; + do { + MOZ_ASSERT(cur->mPrev == prev); + MOZ_ASSERT(prev->mNext == cur); + + prev = cur; + cur = cur->mNext; + } while (cur != &sentinel); +#endif /* ifdef DEBUG */ + } + +private: + friend class LinkedListElement<T>; + + void assertContains(const RawType aValue) const + { +#ifdef DEBUG + for (ConstRawType elem = getFirst(); elem; elem = elem->getNext()) { + if (elem == aValue) { + return; + } + } + MOZ_CRASH("element wasn't found in this list!"); +#endif + } + + LinkedList& operator=(const LinkedList<T>& aOther) = delete; + LinkedList(const LinkedList<T>& aOther) = delete; +}; + +template <typename T> +class AutoCleanLinkedList : public LinkedList<T> +{ +public: + ~AutoCleanLinkedList() + { + while (T* element = this->popFirst()) { + delete element; + } + } +}; + +} /* namespace mozilla */ + +#endif /* __cplusplus */ + +#endif /* mozilla_LinkedList_h */ diff --git a/mfbt/LinuxSignal.h b/mfbt/LinuxSignal.h new file mode 100644 index 000000000..83c2bf81f --- /dev/null +++ b/mfbt/LinuxSignal.h @@ -0,0 +1,45 @@ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef mozilla_LinuxSignal_h +#define mozilla_LinuxSignal_h + +namespace mozilla { + +#if defined(__arm__) + +// Some (old) Linux kernels on ARM have a bug where a signal handler +// can be called without clearing the IT bits in CPSR first. The result +// is that the first few instructions of the handler could be skipped, +// ultimately resulting in crashes. To workaround this bug, the handler +// on ARM is a trampoline that starts with enough NOP instructions, so +// that even if the IT bits are not cleared, only the NOP instructions +// will be skipped over. + +template <void (*H)(int, siginfo_t*, void*)> +__attribute__((naked)) void +SignalTrampoline(int aSignal, siginfo_t* aInfo, void* aContext) +{ + asm volatile ( + "nop; nop; nop; nop" + : : : "memory"); + + asm volatile ( + "b %0" + : + : "X"(H) + : "memory"); +} + +# define MOZ_SIGNAL_TRAMPOLINE(h) (mozilla::SignalTrampoline<h>) + +#else // __arm__ + +# define MOZ_SIGNAL_TRAMPOLINE(h) (h) + +#endif // __arm__ + +} // namespace mozilla + +#endif // mozilla_LinuxSignal_h diff --git a/mfbt/MacroArgs.h b/mfbt/MacroArgs.h new file mode 100644 index 000000000..52ed1e828 --- /dev/null +++ b/mfbt/MacroArgs.h @@ -0,0 +1,109 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* + * Implements various macros meant to ease the use of variadic macros. + */ + +#ifndef mozilla_MacroArgs_h +#define mozilla_MacroArgs_h + +// Concatenates pre-processor tokens in a way that can be used with __LINE__. +#define MOZ_CONCAT2(x, y) x ## y +#define MOZ_CONCAT(x, y) MOZ_CONCAT2(x, y) + +/* + * MOZ_PASTE_PREFIX_AND_ARG_COUNT(aPrefix, ...) counts the number of variadic + * arguments and prefixes it with |aPrefix|. For example: + * + * MOZ_PASTE_PREFIX_AND_ARG_COUNT(, foo, 42) expands to 2 + * MOZ_PASTE_PREFIX_AND_ARG_COUNT(A, foo, 42, bar) expands to A3 + * + * You must pass in between 1 and 50 (inclusive) variadic arguments, past + * |aPrefix|. It is not legal to do + * + * MOZ_PASTE_PREFIX_AND_ARG_COUNT(prefix) + * + * (that is, pass in 0 variadic arguments). To ensure that a compile-time + * error occurs when these constraints are violated, use the + * MOZ_STATIC_ASSERT_VALID_ARG_COUNT macro with the same variaidc arguments + * wherever this macro is used. + * + * Passing (__VA_ARGS__, <rest of arguments>) rather than simply calling + * MOZ_MACROARGS_ARG_COUNT_HELPER2(__VA_ARGS__, <rest of arguments>) very + * carefully tiptoes around a MSVC bug where it improperly expands __VA_ARGS__ + * as a single token in argument lists. For details, see: + * + * http://connect.microsoft.com/VisualStudio/feedback/details/380090/variadic-macro-replacement + * http://cplusplus.co.il/2010/07/17/variadic-macro-to-count-number-of-arguments/#comment-644 + */ +#define MOZ_PASTE_PREFIX_AND_ARG_COUNT(aPrefix, ...) \ + MOZ_MACROARGS_ARG_COUNT_HELPER((__VA_ARGS__, \ + aPrefix##50, aPrefix##49, aPrefix##48, aPrefix##47, aPrefix##46, \ + aPrefix##45, aPrefix##44, aPrefix##43, aPrefix##42, aPrefix##41, \ + aPrefix##40, aPrefix##39, aPrefix##38, aPrefix##37, aPrefix##36, \ + aPrefix##35, aPrefix##34, aPrefix##33, aPrefix##32, aPrefix##31, \ + aPrefix##30, aPrefix##29, aPrefix##28, aPrefix##27, aPrefix##26, \ + aPrefix##25, aPrefix##24, aPrefix##23, aPrefix##22, aPrefix##21, \ + aPrefix##20, aPrefix##19, aPrefix##18, aPrefix##17, aPrefix##16, \ + aPrefix##15, aPrefix##14, aPrefix##13, aPrefix##12, aPrefix##11, \ + aPrefix##10, aPrefix##9, aPrefix##8, aPrefix##7, aPrefix##6, \ + aPrefix##5, aPrefix##4, aPrefix##3, aPrefix##2, aPrefix##1, aPrefix##0)) + +#define MOZ_MACROARGS_ARG_COUNT_HELPER(aArgs) \ + MOZ_MACROARGS_ARG_COUNT_HELPER2 aArgs + +#define MOZ_MACROARGS_ARG_COUNT_HELPER2( \ + a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, \ + a11, a12, a13, a14, a15, a16, a17, a18, a19, a20, \ + a21, a22, a23, a24, a25, a26, a27, a28, a29, a30, \ + a31, a32, a33, a34, a35, a36, a37, a38, a39, a40, \ + a41, a42, a43, a44, a45, a46, a47, a48, a49, a50, \ + a51, ...) a51 + +/* + * MOZ_STATIC_ASSERT_VALID_ARG_COUNT ensures that a compile-time error occurs + * when the argument count constraints of MOZ_PASTE_PREFIX_AND_ARG_COUNT are + * violated. Use this macro wherever MOZ_PASTE_PREFIX_AND_ARG_COUNT is used + * and pass it the same variadic arguments. + * + * This macro employs a few dirty tricks to function. To detect the zero + * argument case, |(__VA_ARGS__)| is stringified, sizeof-ed, and compared to + * what it should be in the absence of arguments. + * + * Detecting too many arguments is a little trickier. With a valid argument + * count and a prefix of 1, MOZ_PASTE_PREFIX_AND_ARG_COUNT expands to e.g. 14. + * With a prefix of 0.0, it expands to e.g. 0.04. If there are too many + * arguments, it expands to the first argument over the limit. If this + * exceeding argument is a number, the assertion will fail as there is no + * number than can simultaneously be both > 10 and == 0. If the exceeding + * argument is not a number, a compile-time error should still occur due to + * the operations performed on it. + */ +#define MOZ_MACROARGS_STRINGIFY_HELPER(x) #x +#define MOZ_STATIC_ASSERT_VALID_ARG_COUNT(...) \ + static_assert( \ + sizeof(MOZ_MACROARGS_STRINGIFY_HELPER((__VA_ARGS__))) != sizeof("()") && \ + (MOZ_PASTE_PREFIX_AND_ARG_COUNT(1, __VA_ARGS__)) > 10 && \ + (int)(MOZ_PASTE_PREFIX_AND_ARG_COUNT(0.0, __VA_ARGS__)) == 0, \ + "MOZ_STATIC_ASSERT_VALID_ARG_COUNT requires 1 to 50 arguments") /* ; */ + +/* + * MOZ_ARGS_AFTER_N expands to its arguments excluding the first |N| + * arguments. For example: + * + * MOZ_ARGS_AFTER_2(a, b, c, d) expands to: c, d + */ +#define MOZ_ARGS_AFTER_1(a1, ...) __VA_ARGS__ +#define MOZ_ARGS_AFTER_2(a1, a2, ...) __VA_ARGS__ + +/* + * MOZ_ARG_N expands to its |N|th argument. + */ +#define MOZ_ARG_1(a1, ...) a1 +#define MOZ_ARG_2(a1, a2, ...) a2 + +#endif /* mozilla_MacroArgs_h */ diff --git a/mfbt/MacroForEach.h b/mfbt/MacroForEach.h new file mode 100644 index 000000000..7c0e3cfbb --- /dev/null +++ b/mfbt/MacroForEach.h @@ -0,0 +1,158 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* + * Implements a higher-order macro for iteratively calling another macro with + * fixed leading arguments, plus a trailing element picked from a second list + * of arguments. + */ + +#ifndef mozilla_MacroForEach_h +#define mozilla_MacroForEach_h + +#include "mozilla/MacroArgs.h" + +/* + * MOZ_FOR_EACH(aMacro, aFixedArgs, aArgs) expands to N calls to the macro + * |aMacro| where N is equal the number of items in the list |aArgs|. The + * arguments for each |aMacro| call are composed of *all* arguments in the list + * |aFixedArgs| as well as a single argument in the list |aArgs|. For example: + * + * #define MACRO_A(x) x + + * int a = MOZ_FOR_EACH(MACRO_A, (), (1, 2, 3)) 0; + * // Expands to: MACRO_A(1) MACRO_A(2) MACRO_A(3) 0; + * // And further to: 1 + 2 + 3 + 0; + * + * #define MACRO_B(k, x) (k + x) + + * int b = MOZ_FOR_EACH(MACRO_B, (5,), (1, 2)) 0; + * // Expands to: MACRO_B(5, 1) MACRO_B(5, 2) 0; + * + * #define MACRO_C(k1, k2, x) (k1 + k2 + x) + + * int c = MOZ_FOR_EACH(MACRO_C, (5, 8,), (1, 2)) 0; + * // Expands to: MACRO_B(5, 8, 1) MACRO_B(5, 8, 2) 0; + * + * If the |aFixedArgs| list is not empty, a trailing comma must be included. + * + * The |aArgs| list must be not be empty and may be up to 50 items long. Use + * MOZ_STATIC_ASSERT_VALID_ARG_COUNT to ensure that violating this constraint + * results in a compile-time error. + */ +#define MOZ_FOR_EACH_EXPAND_HELPER(...) __VA_ARGS__ +#define MOZ_FOR_EACH_GLUE(a, b) a b +#define MOZ_FOR_EACH(aMacro, aFixedArgs, aArgs) \ + MOZ_FOR_EACH_GLUE( \ + MOZ_PASTE_PREFIX_AND_ARG_COUNT(MOZ_FOR_EACH_, \ + MOZ_FOR_EACH_EXPAND_HELPER aArgs), \ + (aMacro, aFixedArgs, aArgs)) + +#define MOZ_FOR_EACH_HELPER_GLUE(a, b) a b +#define MOZ_FOR_EACH_HELPER(aMacro, aFixedArgs, aArgs) \ + MOZ_FOR_EACH_HELPER_GLUE( \ + aMacro, \ + (MOZ_FOR_EACH_EXPAND_HELPER aFixedArgs MOZ_ARG_1 aArgs)) + +#define MOZ_FOR_EACH_1(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) +#define MOZ_FOR_EACH_2(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_1(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_3(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_2(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_4(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_3(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_5(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_4(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_6(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_5(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_7(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_6(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_8(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_7(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_9(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_8(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_10(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_9(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_11(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_10(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_12(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_11(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_13(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_12(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_14(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_13(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_15(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_14(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_16(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_15(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_17(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_16(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_18(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_17(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_19(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_18(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_20(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_19(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_21(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_20(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_22(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_21(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_23(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_22(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_24(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_23(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_25(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_24(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_26(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_25(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_27(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_26(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_28(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_27(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_29(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_28(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_30(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_29(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_31(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_30(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_32(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_31(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_33(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_32(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_34(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_33(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_35(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_34(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_36(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_35(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_37(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_36(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_38(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_37(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_39(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_38(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_40(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_39(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_41(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_40(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_42(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_41(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_43(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_42(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_44(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_43(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_45(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_44(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_46(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_45(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_47(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_46(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_48(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_47(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_49(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_48(m, fa, (MOZ_ARGS_AFTER_1 a)) +#define MOZ_FOR_EACH_50(m, fa, a) \ + MOZ_FOR_EACH_HELPER(m, fa, a) MOZ_FOR_EACH_49(m, fa, (MOZ_ARGS_AFTER_1 a)) + +#endif /* mozilla_MacroForEach_h */ diff --git a/mfbt/MathAlgorithms.h b/mfbt/MathAlgorithms.h new file mode 100644 index 000000000..4db6de497 --- /dev/null +++ b/mfbt/MathAlgorithms.h @@ -0,0 +1,547 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* mfbt maths algorithms. */ + +#ifndef mozilla_MathAlgorithms_h +#define mozilla_MathAlgorithms_h + +#include "mozilla/Assertions.h" +#include "mozilla/TypeTraits.h" + +#include <cmath> +#include <limits.h> +#include <stdint.h> + +namespace mozilla { + +// Greatest Common Divisor +template<typename IntegerType> +MOZ_ALWAYS_INLINE IntegerType +EuclidGCD(IntegerType aA, IntegerType aB) +{ + // Euclid's algorithm; O(N) in the worst case. (There are better + // ways, but we don't need them for the current use of this algo.) + MOZ_ASSERT(aA > IntegerType(0)); + MOZ_ASSERT(aB > IntegerType(0)); + + while (aA != aB) { + if (aA > aB) { + aA = aA - aB; + } else { + aB = aB - aA; + } + } + + return aA; +} + +// Least Common Multiple +template<typename IntegerType> +MOZ_ALWAYS_INLINE IntegerType +EuclidLCM(IntegerType aA, IntegerType aB) +{ + // Divide first to reduce overflow risk. + return (aA / EuclidGCD(aA, aB)) * aB; +} + +namespace detail { + +template<typename T> +struct AllowDeprecatedAbsFixed : FalseType {}; + +template<> struct AllowDeprecatedAbsFixed<int32_t> : TrueType {}; +template<> struct AllowDeprecatedAbsFixed<int64_t> : TrueType {}; + +template<typename T> +struct AllowDeprecatedAbs : AllowDeprecatedAbsFixed<T> {}; + +template<> struct AllowDeprecatedAbs<int> : TrueType {}; +template<> struct AllowDeprecatedAbs<long> : TrueType {}; + +} // namespace detail + +// DO NOT USE DeprecatedAbs. It exists only until its callers can be converted +// to Abs below, and it will be removed when all callers have been changed. +template<typename T> +inline typename mozilla::EnableIf<detail::AllowDeprecatedAbs<T>::value, T>::Type +DeprecatedAbs(const T aValue) +{ + // The absolute value of the smallest possible value of a signed-integer type + // won't fit in that type (on twos-complement systems -- and we're blithely + // assuming we're on such systems, for the non-<stdint.h> types listed above), + // so assert that the input isn't that value. + // + // This is the case if: the value is non-negative; or if adding one (giving a + // value in the range [-maxvalue, 0]), then negating (giving a value in the + // range [0, maxvalue]), doesn't produce maxvalue (because in twos-complement, + // (minvalue + 1) == -maxvalue). + MOZ_ASSERT(aValue >= 0 || + -(aValue + 1) != T((1ULL << (CHAR_BIT * sizeof(T) - 1)) - 1), + "You can't negate the smallest possible negative integer!"); + return aValue >= 0 ? aValue : -aValue; +} + +namespace detail { + +// For now mozilla::Abs only takes intN_T, the signed natural types, and +// float/double/long double. Feel free to add overloads for other standard, +// signed types if you need them. + +template<typename T> +struct AbsReturnTypeFixed; + +template<> struct AbsReturnTypeFixed<int8_t> { typedef uint8_t Type; }; +template<> struct AbsReturnTypeFixed<int16_t> { typedef uint16_t Type; }; +template<> struct AbsReturnTypeFixed<int32_t> { typedef uint32_t Type; }; +template<> struct AbsReturnTypeFixed<int64_t> { typedef uint64_t Type; }; + +template<typename T> +struct AbsReturnType : AbsReturnTypeFixed<T> {}; + +template<> struct AbsReturnType<char> : + EnableIf<char(-1) < char(0), unsigned char> {}; +template<> struct AbsReturnType<signed char> { typedef unsigned char Type; }; +template<> struct AbsReturnType<short> { typedef unsigned short Type; }; +template<> struct AbsReturnType<int> { typedef unsigned int Type; }; +template<> struct AbsReturnType<long> { typedef unsigned long Type; }; +template<> struct AbsReturnType<long long> { typedef unsigned long long Type; }; +template<> struct AbsReturnType<float> { typedef float Type; }; +template<> struct AbsReturnType<double> { typedef double Type; }; +template<> struct AbsReturnType<long double> { typedef long double Type; }; + +} // namespace detail + +template<typename T> +inline typename detail::AbsReturnType<T>::Type +Abs(const T aValue) +{ + typedef typename detail::AbsReturnType<T>::Type ReturnType; + return aValue >= 0 ? ReturnType(aValue) : ~ReturnType(aValue) + 1; +} + +template<> +inline float +Abs<float>(const float aFloat) +{ + return std::fabs(aFloat); +} + +template<> +inline double +Abs<double>(const double aDouble) +{ + return std::fabs(aDouble); +} + +template<> +inline long double +Abs<long double>(const long double aLongDouble) +{ + return std::fabs(aLongDouble); +} + +} // namespace mozilla + +#if defined(_MSC_VER) && \ + (defined(_M_IX86) || defined(_M_AMD64) || defined(_M_X64)) +# define MOZ_BITSCAN_WINDOWS + +# include <intrin.h> +# pragma intrinsic(_BitScanForward, _BitScanReverse) + +# if defined(_M_AMD64) || defined(_M_X64) +# define MOZ_BITSCAN_WINDOWS64 +# pragma intrinsic(_BitScanForward64, _BitScanReverse64) +# endif + +#endif + +namespace mozilla { + +namespace detail { + +#if defined(MOZ_BITSCAN_WINDOWS) + +inline uint_fast8_t +CountLeadingZeroes32(uint32_t aValue) +{ + unsigned long index; + if (!_BitScanReverse(&index, static_cast<unsigned long>(aValue))) + return 32; + return uint_fast8_t(31 - index); +} + + +inline uint_fast8_t +CountTrailingZeroes32(uint32_t aValue) +{ + unsigned long index; + if (!_BitScanForward(&index, static_cast<unsigned long>(aValue))) + return 32; + return uint_fast8_t(index); +} + +inline uint_fast8_t +CountPopulation32(uint32_t aValue) +{ + uint32_t x = aValue - ((aValue >> 1) & 0x55555555); + x = (x & 0x33333333) + ((x >> 2) & 0x33333333); + return (((x + (x >> 4)) & 0xf0f0f0f) * 0x1010101) >> 24; +} +inline uint_fast8_t +CountPopulation64(uint64_t aValue) +{ + return uint_fast8_t(CountPopulation32(aValue & 0xffffffff) + + CountPopulation32(aValue >> 32)); +} + +inline uint_fast8_t +CountLeadingZeroes64(uint64_t aValue) +{ +#if defined(MOZ_BITSCAN_WINDOWS64) + unsigned long index; + if (!_BitScanReverse64(&index, static_cast<unsigned __int64>(aValue))) + return 64; + return uint_fast8_t(63 - index); +#else + uint32_t hi = uint32_t(aValue >> 32); + if (hi != 0) { + return CountLeadingZeroes32(hi); + } + return 32u + CountLeadingZeroes32(uint32_t(aValue)); +#endif +} + +inline uint_fast8_t +CountTrailingZeroes64(uint64_t aValue) +{ +#if defined(MOZ_BITSCAN_WINDOWS64) + unsigned long index; + if (!_BitScanForward64(&index, static_cast<unsigned __int64>(aValue))) + return 64; + return uint_fast8_t(index); +#else + uint32_t lo = uint32_t(aValue); + if (lo != 0) { + return CountTrailingZeroes32(lo); + } + return 32u + CountTrailingZeroes32(uint32_t(aValue >> 32)); +#endif +} + +# ifdef MOZ_HAVE_BITSCAN64 +# undef MOZ_HAVE_BITSCAN64 +# endif + +#elif defined(__clang__) || defined(__GNUC__) + +# if defined(__clang__) +# if !__has_builtin(__builtin_ctz) || !__has_builtin(__builtin_clz) +# error "A clang providing __builtin_c[lt]z is required to build" +# endif +# else + // gcc has had __builtin_clz and friends since 3.4: no need to check. +# endif + +inline uint_fast8_t +CountLeadingZeroes32(uint32_t aValue) +{ + return __builtin_clz(aValue); +} + +inline uint_fast8_t +CountTrailingZeroes32(uint32_t aValue) +{ + return __builtin_ctz(aValue); +} + +inline uint_fast8_t +CountPopulation32(uint32_t aValue) +{ + return __builtin_popcount(aValue); +} + +inline uint_fast8_t +CountPopulation64(uint64_t aValue) +{ + return __builtin_popcountll(aValue); +} + +inline uint_fast8_t +CountLeadingZeroes64(uint64_t aValue) +{ + return __builtin_clzll(aValue); +} + +inline uint_fast8_t +CountTrailingZeroes64(uint64_t aValue) +{ + return __builtin_ctzll(aValue); +} + +#else +# error "Implement these!" +inline uint_fast8_t CountLeadingZeroes32(uint32_t aValue) = delete; +inline uint_fast8_t CountTrailingZeroes32(uint32_t aValue) = delete; +inline uint_fast8_t CountPopulation32(uint32_t aValue) = delete; +inline uint_fast8_t CountPopulation64(uint64_t aValue) = delete; +inline uint_fast8_t CountLeadingZeroes64(uint64_t aValue) = delete; +inline uint_fast8_t CountTrailingZeroes64(uint64_t aValue) = delete; +#endif + +} // namespace detail + +/** + * Compute the number of high-order zero bits in the NON-ZERO number |aValue|. + * That is, looking at the bitwise representation of the number, with the + * highest- valued bits at the start, return the number of zeroes before the + * first one is observed. + * + * CountLeadingZeroes32(0xF0FF1000) is 0; + * CountLeadingZeroes32(0x7F8F0001) is 1; + * CountLeadingZeroes32(0x3FFF0100) is 2; + * CountLeadingZeroes32(0x1FF50010) is 3; and so on. + */ +inline uint_fast8_t +CountLeadingZeroes32(uint32_t aValue) +{ + MOZ_ASSERT(aValue != 0); + return detail::CountLeadingZeroes32(aValue); +} + +/** + * Compute the number of low-order zero bits in the NON-ZERO number |aValue|. + * That is, looking at the bitwise representation of the number, with the + * lowest- valued bits at the start, return the number of zeroes before the + * first one is observed. + * + * CountTrailingZeroes32(0x0100FFFF) is 0; + * CountTrailingZeroes32(0x7000FFFE) is 1; + * CountTrailingZeroes32(0x0080FFFC) is 2; + * CountTrailingZeroes32(0x0080FFF8) is 3; and so on. + */ +inline uint_fast8_t +CountTrailingZeroes32(uint32_t aValue) +{ + MOZ_ASSERT(aValue != 0); + return detail::CountTrailingZeroes32(aValue); +} + +/** + * Compute the number of one bits in the number |aValue|, + */ +inline uint_fast8_t +CountPopulation32(uint32_t aValue) +{ + return detail::CountPopulation32(aValue); +} + +/** Analogous to CountPopulation32, but for 64-bit numbers */ +inline uint_fast8_t +CountPopulation64(uint64_t aValue) +{ + return detail::CountPopulation64(aValue); +} + +/** Analogous to CountLeadingZeroes32, but for 64-bit numbers. */ +inline uint_fast8_t +CountLeadingZeroes64(uint64_t aValue) +{ + MOZ_ASSERT(aValue != 0); + return detail::CountLeadingZeroes64(aValue); +} + +/** Analogous to CountTrailingZeroes32, but for 64-bit numbers. */ +inline uint_fast8_t +CountTrailingZeroes64(uint64_t aValue) +{ + MOZ_ASSERT(aValue != 0); + return detail::CountTrailingZeroes64(aValue); +} + +namespace detail { + +template<typename T, size_t Size = sizeof(T)> +class CeilingLog2; + +template<typename T> +class CeilingLog2<T, 4> +{ +public: + static uint_fast8_t compute(const T aValue) + { + // Check for <= 1 to avoid the == 0 undefined case. + return aValue <= 1 ? 0u : 32u - CountLeadingZeroes32(aValue - 1); + } +}; + +template<typename T> +class CeilingLog2<T, 8> +{ +public: + static uint_fast8_t compute(const T aValue) + { + // Check for <= 1 to avoid the == 0 undefined case. + return aValue <= 1 ? 0u : 64u - CountLeadingZeroes64(aValue - 1); + } +}; + +} // namespace detail + +/** + * Compute the log of the least power of 2 greater than or equal to |aValue|. + * + * CeilingLog2(0..1) is 0; + * CeilingLog2(2) is 1; + * CeilingLog2(3..4) is 2; + * CeilingLog2(5..8) is 3; + * CeilingLog2(9..16) is 4; and so on. + */ +template<typename T> +inline uint_fast8_t +CeilingLog2(const T aValue) +{ + return detail::CeilingLog2<T>::compute(aValue); +} + +/** A CeilingLog2 variant that accepts only size_t. */ +inline uint_fast8_t +CeilingLog2Size(size_t aValue) +{ + return CeilingLog2(aValue); +} + +namespace detail { + +template<typename T, size_t Size = sizeof(T)> +class FloorLog2; + +template<typename T> +class FloorLog2<T, 4> +{ +public: + static uint_fast8_t compute(const T aValue) + { + return 31u - CountLeadingZeroes32(aValue | 1); + } +}; + +template<typename T> +class FloorLog2<T, 8> +{ +public: + static uint_fast8_t compute(const T aValue) + { + return 63u - CountLeadingZeroes64(aValue | 1); + } +}; + +} // namespace detail + +/** + * Compute the log of the greatest power of 2 less than or equal to |aValue|. + * + * FloorLog2(0..1) is 0; + * FloorLog2(2..3) is 1; + * FloorLog2(4..7) is 2; + * FloorLog2(8..15) is 3; and so on. + */ +template<typename T> +inline uint_fast8_t +FloorLog2(const T aValue) +{ + return detail::FloorLog2<T>::compute(aValue); +} + +/** A FloorLog2 variant that accepts only size_t. */ +inline uint_fast8_t +FloorLog2Size(size_t aValue) +{ + return FloorLog2(aValue); +} + +/* + * Compute the smallest power of 2 greater than or equal to |x|. |x| must not + * be so great that the computed value would overflow |size_t|. + */ +inline size_t +RoundUpPow2(size_t aValue) +{ + MOZ_ASSERT(aValue <= (size_t(1) << (sizeof(size_t) * CHAR_BIT - 1)), + "can't round up -- will overflow!"); + return size_t(1) << CeilingLog2(aValue); +} + +/** + * Rotates the bits of the given value left by the amount of the shift width. + */ +template<typename T> +inline T +RotateLeft(const T aValue, uint_fast8_t aShift) +{ + MOZ_ASSERT(aShift < sizeof(T) * CHAR_BIT, "Shift value is too large!"); + MOZ_ASSERT(aShift > 0, + "Rotation by value length is undefined behavior, but compilers " + "do not currently fold a test into the rotate instruction. " + "Please remove this restriction when compilers optimize the " + "zero case (http://blog.regehr.org/archives/1063)."); + static_assert(IsUnsigned<T>::value, "Rotates require unsigned values"); + return (aValue << aShift) | (aValue >> (sizeof(T) * CHAR_BIT - aShift)); +} + +/** + * Rotates the bits of the given value right by the amount of the shift width. + */ +template<typename T> +inline T +RotateRight(const T aValue, uint_fast8_t aShift) +{ + MOZ_ASSERT(aShift < sizeof(T) * CHAR_BIT, "Shift value is too large!"); + MOZ_ASSERT(aShift > 0, + "Rotation by value length is undefined behavior, but compilers " + "do not currently fold a test into the rotate instruction. " + "Please remove this restriction when compilers optimize the " + "zero case (http://blog.regehr.org/archives/1063)."); + static_assert(IsUnsigned<T>::value, "Rotates require unsigned values"); + return (aValue >> aShift) | (aValue << (sizeof(T) * CHAR_BIT - aShift)); +} + +/** + * Returns true if |x| is a power of two. + * Zero is not an integer power of two. (-Inf is not an integer) + */ +template<typename T> +constexpr bool +IsPowerOfTwo(T x) +{ + static_assert(IsUnsigned<T>::value, + "IsPowerOfTwo requires unsigned values"); + return x && (x & (x - 1)) == 0; +} + +template<typename T> +inline T +Clamp(const T aValue, const T aMin, const T aMax) +{ + static_assert(IsIntegral<T>::value, + "Clamp accepts only integral types, so that it doesn't have" + " to distinguish differently-signed zeroes (which users may" + " or may not care to distinguish, likely at a perf cost) or" + " to decide how to clamp NaN or a range with a NaN" + " endpoint."); + MOZ_ASSERT(aMin <= aMax); + + if (aValue <= aMin) + return aMin; + if (aValue >= aMax) + return aMax; + return aValue; +} + +} /* namespace mozilla */ + +#endif /* mozilla_MathAlgorithms_h */ diff --git a/mfbt/Maybe.h b/mfbt/Maybe.h new file mode 100644 index 000000000..2a601ac49 --- /dev/null +++ b/mfbt/Maybe.h @@ -0,0 +1,551 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* A class for optional values and in-place lazy construction. */ + +#ifndef mozilla_Maybe_h +#define mozilla_Maybe_h + +#include "mozilla/Alignment.h" +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" +#include "mozilla/Move.h" +#include "mozilla/TypeTraits.h" + +#include <new> // for placement new +#include <type_traits> + +namespace mozilla { + +struct Nothing { }; + +/* + * Maybe is a container class which contains either zero or one elements. It + * serves two roles. It can represent values which are *semantically* optional, + * augmenting a type with an explicit 'Nothing' value. In this role, it provides + * methods that make it easy to work with values that may be missing, along with + * equality and comparison operators so that Maybe values can be stored in + * containers. Maybe values can be constructed conveniently in expressions using + * type inference, as follows: + * + * void doSomething(Maybe<Foo> aFoo) { + * if (aFoo) // Make sure that aFoo contains a value... + * aFoo->takeAction(); // and then use |aFoo->| to access it. + * } // |*aFoo| also works! + * + * doSomething(Nothing()); // Passes a Maybe<Foo> containing no value. + * doSomething(Some(Foo(100))); // Passes a Maybe<Foo> containing |Foo(100)|. + * + * You'll note that it's important to check whether a Maybe contains a value + * before using it, using conversion to bool, |isSome()|, or |isNothing()|. You + * can avoid these checks, and sometimes write more readable code, using + * |valueOr()|, |ptrOr()|, and |refOr()|, which allow you to retrieve the value + * in the Maybe and provide a default for the 'Nothing' case. You can also use + * |apply()| to call a function only if the Maybe holds a value, and |map()| to + * transform the value in the Maybe, returning another Maybe with a possibly + * different type. + * + * Maybe's other role is to support lazily constructing objects without using + * dynamic storage. A Maybe directly contains storage for a value, but it's + * empty by default. |emplace()|, as mentioned above, can be used to construct a + * value in Maybe's storage. The value a Maybe contains can be destroyed by + * calling |reset()|; this will happen automatically if a Maybe is destroyed + * while holding a value. + * + * It's a common idiom in C++ to use a pointer as a 'Maybe' type, with a null + * value meaning 'Nothing' and any other value meaning 'Some'. You can convert + * from such a pointer to a Maybe value using 'ToMaybe()'. + * + * Maybe is inspired by similar types in the standard library of many other + * languages (e.g. Haskell's Maybe and Rust's Option). In the C++ world it's + * very similar to std::optional, which was proposed for C++14 and originated in + * Boost. The most important differences between Maybe and std::optional are: + * + * - std::optional<T> may be compared with T. We deliberately forbid that. + * - std::optional allows in-place construction without a separate call to + * |emplace()| by using a dummy |in_place_t| value to tag the appropriate + * constructor. + * - std::optional has |valueOr()|, equivalent to Maybe's |valueOr()|, but + * lacks corresponding methods for |refOr()| and |ptrOr()|. + * - std::optional lacks |map()| and |apply()|, making it less suitable for + * functional-style code. + * - std::optional lacks many convenience functions that Maybe has. Most + * unfortunately, it lacks equivalents of the type-inferred constructor + * functions |Some()| and |Nothing()|. + * + * N.B. GCC has missed optimizations with Maybe in the past and may generate + * extra branches/loads/stores. Use with caution on hot paths; it's not known + * whether or not this is still a problem. + */ +template<class T> +class Maybe +{ + bool mIsSome; + AlignedStorage2<T> mStorage; + +public: + typedef T ValueType; + + Maybe() : mIsSome(false) { } + ~Maybe() { reset(); } + + MOZ_IMPLICIT Maybe(Nothing) : mIsSome(false) { } + + Maybe(const Maybe& aOther) + : mIsSome(false) + { + if (aOther.mIsSome) { + emplace(*aOther); + } + } + + /** + * Maybe<T*> can be copy-constructed from a Maybe<U*> if U* and T* are + * compatible, or from Maybe<decltype(nullptr)>. + */ + template<typename U, + typename = + typename std::enable_if<std::is_pointer<T>::value && + (std::is_same<U, decltype(nullptr)>::value || + (std::is_pointer<U>::value && + std::is_base_of<typename std::remove_pointer<T>::type, + typename std::remove_pointer<U>::type>::value))>::type> + MOZ_IMPLICIT + Maybe(const Maybe<U>& aOther) + : mIsSome(false) + { + if (aOther.isSome()) { + emplace(*aOther); + } + } + + Maybe(Maybe&& aOther) + : mIsSome(false) + { + if (aOther.mIsSome) { + emplace(Move(*aOther)); + aOther.reset(); + } + } + + /** + * Maybe<T*> can be move-constructed from a Maybe<U*> if U* and T* are + * compatible, or from Maybe<decltype(nullptr)>. + */ + template<typename U, + typename = + typename std::enable_if<std::is_pointer<T>::value && + (std::is_same<U, decltype(nullptr)>::value || + (std::is_pointer<U>::value && + std::is_base_of<typename std::remove_pointer<T>::type, + typename std::remove_pointer<U>::type>::value))>::type> + MOZ_IMPLICIT + Maybe(Maybe<U>&& aOther) + : mIsSome(false) + { + if (aOther.isSome()) { + emplace(Move(*aOther)); + aOther.reset(); + } + } + + Maybe& operator=(const Maybe& aOther) + { + if (&aOther != this) { + if (aOther.mIsSome) { + if (mIsSome) { + // XXX(seth): The correct code for this branch, below, can't be used + // due to a bug in Visual Studio 2010. See bug 1052940. + /* + ref() = aOther.ref(); + */ + reset(); + emplace(*aOther); + } else { + emplace(*aOther); + } + } else { + reset(); + } + } + return *this; + } + + Maybe& operator=(Maybe&& aOther) + { + MOZ_ASSERT(this != &aOther, "Self-moves are prohibited"); + + if (aOther.mIsSome) { + if (mIsSome) { + ref() = Move(aOther.ref()); + } else { + emplace(Move(*aOther)); + } + aOther.reset(); + } else { + reset(); + } + + return *this; + } + + /* Methods that check whether this Maybe contains a value */ + explicit operator bool() const { return isSome(); } + bool isSome() const { return mIsSome; } + bool isNothing() const { return !mIsSome; } + + /* Returns the contents of this Maybe<T> by value. Unsafe unless |isSome()|. */ + T value() const + { + MOZ_ASSERT(mIsSome); + return ref(); + } + + /* + * Returns the contents of this Maybe<T> by value. If |isNothing()|, returns + * the default value provided. + */ + template<typename V> + T valueOr(V&& aDefault) const + { + if (isSome()) { + return ref(); + } + return Forward<V>(aDefault); + } + + /* + * Returns the contents of this Maybe<T> by value. If |isNothing()|, returns + * the value returned from the function or functor provided. + */ + template<typename F> + T valueOrFrom(F&& aFunc) const + { + if (isSome()) { + return ref(); + } + return aFunc(); + } + + /* Returns the contents of this Maybe<T> by pointer. Unsafe unless |isSome()|. */ + T* ptr() + { + MOZ_ASSERT(mIsSome); + return &ref(); + } + + const T* ptr() const + { + MOZ_ASSERT(mIsSome); + return &ref(); + } + + /* + * Returns the contents of this Maybe<T> by pointer. If |isNothing()|, + * returns the default value provided. + */ + T* ptrOr(T* aDefault) + { + if (isSome()) { + return ptr(); + } + return aDefault; + } + + const T* ptrOr(const T* aDefault) const + { + if (isSome()) { + return ptr(); + } + return aDefault; + } + + /* + * Returns the contents of this Maybe<T> by pointer. If |isNothing()|, + * returns the value returned from the function or functor provided. + */ + template<typename F> + T* ptrOrFrom(F&& aFunc) + { + if (isSome()) { + return ptr(); + } + return aFunc(); + } + + template<typename F> + const T* ptrOrFrom(F&& aFunc) const + { + if (isSome()) { + return ptr(); + } + return aFunc(); + } + + T* operator->() + { + MOZ_ASSERT(mIsSome); + return ptr(); + } + + const T* operator->() const + { + MOZ_ASSERT(mIsSome); + return ptr(); + } + + /* Returns the contents of this Maybe<T> by ref. Unsafe unless |isSome()|. */ + T& ref() + { + MOZ_ASSERT(mIsSome); + return *mStorage.addr(); + } + + const T& ref() const + { + MOZ_ASSERT(mIsSome); + return *mStorage.addr(); + } + + /* + * Returns the contents of this Maybe<T> by ref. If |isNothing()|, returns + * the default value provided. + */ + T& refOr(T& aDefault) + { + if (isSome()) { + return ref(); + } + return aDefault; + } + + const T& refOr(const T& aDefault) const + { + if (isSome()) { + return ref(); + } + return aDefault; + } + + /* + * Returns the contents of this Maybe<T> by ref. If |isNothing()|, returns the + * value returned from the function or functor provided. + */ + template<typename F> + T& refOrFrom(F&& aFunc) + { + if (isSome()) { + return ref(); + } + return aFunc(); + } + + template<typename F> + const T& refOrFrom(F&& aFunc) const + { + if (isSome()) { + return ref(); + } + return aFunc(); + } + + T& operator*() + { + MOZ_ASSERT(mIsSome); + return ref(); + } + + const T& operator*() const + { + MOZ_ASSERT(mIsSome); + return ref(); + } + + /* If |isSome()|, runs the provided function or functor on the contents of + * this Maybe. */ + template<typename Func> + Maybe& apply(Func aFunc) + { + if (isSome()) { + aFunc(ref()); + } + return *this; + } + + template<typename Func> + const Maybe& apply(Func aFunc) const + { + if (isSome()) { + aFunc(ref()); + } + return *this; + } + + /* + * If |isSome()|, runs the provided function and returns the result wrapped + * in a Maybe. If |isNothing()|, returns an empty Maybe value. + */ + template<typename Func> + auto map(Func aFunc) -> Maybe<decltype(aFunc(DeclVal<Maybe<T>>().ref()))> + { + using ReturnType = decltype(aFunc(ref())); + if (isSome()) { + Maybe<ReturnType> val; + val.emplace(aFunc(ref())); + return val; + } + return Maybe<ReturnType>(); + } + + template<typename Func> + auto map(Func aFunc) const -> Maybe<decltype(aFunc(DeclVal<Maybe<T>>().ref()))> + { + using ReturnType = decltype(aFunc(ref())); + if (isSome()) { + Maybe<ReturnType> val; + val.emplace(aFunc(ref())); + return val; + } + return Maybe<ReturnType>(); + } + + /* If |isSome()|, empties this Maybe and destroys its contents. */ + void reset() + { + if (isSome()) { + ref().T::~T(); + mIsSome = false; + } + } + + /* + * Constructs a T value in-place in this empty Maybe<T>'s storage. The + * arguments to |emplace()| are the parameters to T's constructor. + */ + template<typename... Args> + void emplace(Args&&... aArgs) + { + MOZ_ASSERT(!mIsSome); + ::new (mStorage.addr()) T(Forward<Args>(aArgs)...); + mIsSome = true; + } +}; + +/* + * Some() creates a Maybe<T> value containing the provided T value. If T has a + * move constructor, it's used to make this as efficient as possible. + * + * Some() selects the type of Maybe it returns by removing any const, volatile, + * or reference qualifiers from the type of the value you pass to it. This gives + * it more intuitive behavior when used in expressions, but it also means that + * if you need to construct a Maybe value that holds a const, volatile, or + * reference value, you need to use emplace() instead. + */ +template<typename T> +Maybe<typename RemoveCV<typename RemoveReference<T>::Type>::Type> +Some(T&& aValue) +{ + typedef typename RemoveCV<typename RemoveReference<T>::Type>::Type U; + Maybe<U> value; + value.emplace(Forward<T>(aValue)); + return value; +} + +template<typename T> +Maybe<typename RemoveCV<typename RemoveReference<T>::Type>::Type> +ToMaybe(T* aPtr) +{ + if (aPtr) { + return Some(*aPtr); + } + return Nothing(); +} + +/* + * Two Maybe<T> values are equal if + * - both are Nothing, or + * - both are Some, and the values they contain are equal. + */ +template<typename T> bool +operator==(const Maybe<T>& aLHS, const Maybe<T>& aRHS) +{ + if (aLHS.isNothing() != aRHS.isNothing()) { + return false; + } + return aLHS.isNothing() || *aLHS == *aRHS; +} + +template<typename T> bool +operator!=(const Maybe<T>& aLHS, const Maybe<T>& aRHS) +{ + return !(aLHS == aRHS); +} + +/* + * We support comparison to Nothing to allow reasonable expressions like: + * if (maybeValue == Nothing()) { ... } + */ +template<typename T> bool +operator==(const Maybe<T>& aLHS, const Nothing& aRHS) +{ + return aLHS.isNothing(); +} + +template<typename T> bool +operator!=(const Maybe<T>& aLHS, const Nothing& aRHS) +{ + return !(aLHS == aRHS); +} + +template<typename T> bool +operator==(const Nothing& aLHS, const Maybe<T>& aRHS) +{ + return aRHS.isNothing(); +} + +template<typename T> bool +operator!=(const Nothing& aLHS, const Maybe<T>& aRHS) +{ + return !(aLHS == aRHS); +} + +/* + * Maybe<T> values are ordered in the same way T values are ordered, except that + * Nothing comes before anything else. + */ +template<typename T> bool +operator<(const Maybe<T>& aLHS, const Maybe<T>& aRHS) +{ + if (aLHS.isNothing()) { + return aRHS.isSome(); + } + if (aRHS.isNothing()) { + return false; + } + return *aLHS < *aRHS; +} + +template<typename T> bool +operator>(const Maybe<T>& aLHS, const Maybe<T>& aRHS) +{ + return !(aLHS < aRHS || aLHS == aRHS); +} + +template<typename T> bool +operator<=(const Maybe<T>& aLHS, const Maybe<T>& aRHS) +{ + return aLHS < aRHS || aLHS == aRHS; +} + +template<typename T> bool +operator>=(const Maybe<T>& aLHS, const Maybe<T>& aRHS) +{ + return !(aLHS < aRHS); +} + +} // namespace mozilla + +#endif /* mozilla_Maybe_h */ diff --git a/mfbt/MaybeOneOf.h b/mfbt/MaybeOneOf.h new file mode 100644 index 000000000..9c38ff8b0 --- /dev/null +++ b/mfbt/MaybeOneOf.h @@ -0,0 +1,143 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef mozilla_MaybeOneOf_h +#define mozilla_MaybeOneOf_h + +#include "mozilla/Alignment.h" +#include "mozilla/Assertions.h" +#include "mozilla/Move.h" +#include "mozilla/TemplateLib.h" + +#include <new> // For placement new + +namespace mozilla { + +/* + * MaybeOneOf<T1, T2> is like Maybe, but it supports constructing either T1 + * or T2. When a MaybeOneOf<T1, T2> is constructed, it is |empty()|, i.e., + * no value has been constructed and no destructor will be called when the + * MaybeOneOf<T1, T2> is destroyed. Upon calling |construct<T1>()| or + * |construct<T2>()|, a T1 or T2 object will be constructed with the given + * arguments and that object will be destroyed when the owning MaybeOneOf is + * destroyed. + */ +template<class T1, class T2> +class MaybeOneOf +{ + AlignedStorage<tl::Max<sizeof(T1), sizeof(T2)>::value> storage; + + enum State { None, SomeT1, SomeT2 } state; + template <class T, class Ignored = void> struct Type2State {}; + + template <class T> + T& as() + { + MOZ_ASSERT(state == Type2State<T>::result); + return *(T*)storage.addr(); + } + + template <class T> + const T& as() const + { + MOZ_ASSERT(state == Type2State<T>::result); + return *(T*)storage.addr(); + } + +public: + MaybeOneOf() : state(None) {} + ~MaybeOneOf() { destroyIfConstructed(); } + + MaybeOneOf(MaybeOneOf&& rhs) + : state(None) + { + if (!rhs.empty()) { + if (rhs.constructed<T1>()) { + construct<T1>(Move(rhs.as<T1>())); + rhs.as<T1>().~T1(); + } else { + construct<T2>(Move(rhs.as<T2>())); + rhs.as<T2>().~T2(); + } + rhs.state = None; + } + } + + MaybeOneOf &operator=(MaybeOneOf&& rhs) + { + MOZ_ASSERT(this != &rhs, "Self-move is prohibited"); + this->~MaybeOneOf(); + new(this) MaybeOneOf(Move(rhs)); + return *this; + } + + bool empty() const { return state == None; } + + template <class T> + bool constructed() const { return state == Type2State<T>::result; } + + template <class T, class... Args> + void construct(Args&&... aArgs) + { + MOZ_ASSERT(state == None); + state = Type2State<T>::result; + ::new (storage.addr()) T(Forward<Args>(aArgs)...); + } + + template <class T> + T& ref() + { + return as<T>(); + } + + template <class T> + const T& ref() const + { + return as<T>(); + } + + void destroy() + { + MOZ_ASSERT(state == SomeT1 || state == SomeT2); + if (state == SomeT1) { + as<T1>().~T1(); + } else if (state == SomeT2) { + as<T2>().~T2(); + } + state = None; + } + + void destroyIfConstructed() + { + if (!empty()) { + destroy(); + } + } + +private: + MaybeOneOf(const MaybeOneOf& aOther) = delete; + const MaybeOneOf& operator=(const MaybeOneOf& aOther) = delete; +}; + +template <class T1, class T2> +template <class Ignored> +struct MaybeOneOf<T1, T2>::Type2State<T1, Ignored> +{ + typedef MaybeOneOf<T1, T2> Enclosing; + static const typename Enclosing::State result = Enclosing::SomeT1; +}; + +template <class T1, class T2> +template <class Ignored> +struct MaybeOneOf<T1, T2>::Type2State<T2, Ignored> +{ + typedef MaybeOneOf<T1, T2> Enclosing; + static const typename Enclosing::State result = Enclosing::SomeT2; +}; + +} // namespace mozilla + +#endif /* mozilla_MaybeOneOf_h */ diff --git a/mfbt/MemoryChecking.h b/mfbt/MemoryChecking.h new file mode 100644 index 000000000..ff42d7f1c --- /dev/null +++ b/mfbt/MemoryChecking.h @@ -0,0 +1,129 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* + * Provides a common interface to the ASan (AddressSanitizer) and Valgrind + * functions used to mark memory in certain ways. In detail, the following + * three macros are provided: + * + * MOZ_MAKE_MEM_NOACCESS - Mark memory as unsafe to access (e.g. freed) + * MOZ_MAKE_MEM_UNDEFINED - Mark memory as accessible, with content undefined + * MOZ_MAKE_MEM_DEFINED - Mark memory as accessible, with content defined + * + * With Valgrind in use, these directly map to the three respective Valgrind + * macros. With ASan in use, the NOACCESS macro maps to poisoning the memory, + * while the UNDEFINED/DEFINED macros unpoison memory. + * + * With no memory checker available, all macros expand to the empty statement. + */ + +#ifndef mozilla_MemoryChecking_h +#define mozilla_MemoryChecking_h + +#if defined(MOZ_VALGRIND) +#include "valgrind/memcheck.h" +#endif + +#if defined(MOZ_ASAN) || defined(MOZ_VALGRIND) +#define MOZ_HAVE_MEM_CHECKS 1 +#endif + +#if defined(MOZ_ASAN) +#include <stddef.h> + +#include "mozilla/Attributes.h" +#include "mozilla/Types.h" + +#ifdef _MSC_VER +// In clang-cl based ASAN, we link against the memory poisoning functions +// statically. +#define MOZ_ASAN_VISIBILITY +#else +#define MOZ_ASAN_VISIBILITY MOZ_EXPORT +#endif + +extern "C" { +/* These definitions are usually provided through the + * sanitizer/asan_interface.h header installed by ASan. + */ +void MOZ_ASAN_VISIBILITY +__asan_poison_memory_region(void const volatile *addr, size_t size); +void MOZ_ASAN_VISIBILITY +__asan_unpoison_memory_region(void const volatile *addr, size_t size); + +#define MOZ_MAKE_MEM_NOACCESS(addr, size) \ + __asan_poison_memory_region((addr), (size)) + +#define MOZ_MAKE_MEM_UNDEFINED(addr, size) \ + __asan_unpoison_memory_region((addr), (size)) + +#define MOZ_MAKE_MEM_DEFINED(addr, size) \ + __asan_unpoison_memory_region((addr), (size)) + +/* + * These definitions are usually provided through the + * sanitizer/lsan_interface.h header installed by LSan. + */ +void MOZ_EXPORT +__lsan_ignore_object(const void *p); + +} +#elif defined(MOZ_MSAN) +#include <stddef.h> + +#include "mozilla/Types.h" + +extern "C" { +/* These definitions are usually provided through the + * sanitizer/msan_interface.h header installed by MSan. + */ +void MOZ_EXPORT +__msan_poison(void const volatile *addr, size_t size); +void MOZ_EXPORT +__msan_unpoison(void const volatile *addr, size_t size); + +#define MOZ_MAKE_MEM_NOACCESS(addr, size) \ + __msan_poison((addr), (size)) + +#define MOZ_MAKE_MEM_UNDEFINED(addr, size) \ + __msan_poison((addr), (size)) + +#define MOZ_MAKE_MEM_DEFINED(addr, size) \ + __msan_unpoison((addr), (size)) +} +#elif defined(MOZ_VALGRIND) +#define MOZ_MAKE_MEM_NOACCESS(addr, size) \ + VALGRIND_MAKE_MEM_NOACCESS((addr), (size)) + +#define MOZ_MAKE_MEM_UNDEFINED(addr, size) \ + VALGRIND_MAKE_MEM_UNDEFINED((addr), (size)) + +#define MOZ_MAKE_MEM_DEFINED(addr, size) \ + VALGRIND_MAKE_MEM_DEFINED((addr), (size)) +#else + +#define MOZ_MAKE_MEM_NOACCESS(addr, size) do {} while (0) +#define MOZ_MAKE_MEM_UNDEFINED(addr, size) do {} while (0) +#define MOZ_MAKE_MEM_DEFINED(addr, size) do {} while (0) + +#endif + +/* + * MOZ_LSAN_INTENTIONAL_LEAK(X) is a macro to tell LeakSanitizer that X + * points to a value that will intentionally never be deallocated during + * the execution of the process. + * + * Additional uses of this macro should be reviewed by people + * conversant in leak-checking and/or MFBT peers. + */ +#if defined(MOZ_ASAN) +# define MOZ_LSAN_INTENTIONALLY_LEAK_OBJECT(X) __lsan_ignore_object(X) +#else +# define MOZ_LSAN_INTENTIONALLY_LEAK_OBJECT(X) /* nothing */ +#endif // defined(MOZ_ASAN) + + +#endif /* mozilla_MemoryChecking_h */ diff --git a/mfbt/MemoryReporting.h b/mfbt/MemoryReporting.h new file mode 100644 index 000000000..d2340ecf0 --- /dev/null +++ b/mfbt/MemoryReporting.h @@ -0,0 +1,30 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Memory reporting infrastructure. */ + +#ifndef mozilla_MemoryReporting_h +#define mozilla_MemoryReporting_h + +#include <stddef.h> + +#ifdef __cplusplus + +namespace mozilla { + +/* + * This is for functions that are like malloc_usable_size. Such functions are + * used for measuring the size of data structures. + */ +typedef size_t (*MallocSizeOf)(const void* p); + +} /* namespace mozilla */ + +#endif /* __cplusplus */ + +typedef size_t (*MozMallocSizeOf)(const void* p); + +#endif /* mozilla_MemoryReporting_h */ diff --git a/mfbt/Move.h b/mfbt/Move.h new file mode 100644 index 000000000..f6d0bfc1c --- /dev/null +++ b/mfbt/Move.h @@ -0,0 +1,238 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* C++11-style, but C++98-usable, "move references" implementation. */ + +#ifndef mozilla_Move_h +#define mozilla_Move_h + +#include "mozilla/TypeTraits.h" + +namespace mozilla { + +/* + * "Move" References + * + * Some types can be copied much more efficiently if we know the original's + * value need not be preserved --- that is, if we are doing a "move", not a + * "copy". For example, if we have: + * + * Vector<T> u; + * Vector<T> v(u); + * + * the constructor for v must apply a copy constructor to each element of u --- + * taking time linear in the length of u. However, if we know we will not need u + * any more once v has been initialized, then we could initialize v very + * efficiently simply by stealing u's dynamically allocated buffer and giving it + * to v --- a constant-time operation, regardless of the size of u. + * + * Moves often appear in container implementations. For example, when we append + * to a vector, we may need to resize its buffer. This entails moving each of + * its extant elements from the old, smaller buffer to the new, larger buffer. + * But once the elements have been migrated, we're just going to throw away the + * old buffer; we don't care if they still have their values. So if the vector's + * element type can implement "move" more efficiently than "copy", the vector + * resizing should by all means use a "move" operation. Hash tables should also + * use moves when resizing their internal array as entries are added and + * removed. + * + * The details of the optimization, and whether it's worth applying, vary + * from one type to the next: copying an 'int' is as cheap as moving it, so + * there's no benefit in distinguishing 'int' moves from copies. And while + * some constructor calls for complex types are moves, many really have to + * be copies, and can't be optimized this way. So we need: + * + * 1) a way for a type (like Vector) to announce that it can be moved more + * efficiently than it can be copied, and provide an implementation of that + * move operation; and + * + * 2) a way for a particular invocation of a copy constructor to say that it's + * really a move, not a copy, and that the value of the original isn't + * important afterwards (although it must still be safe to destroy). + * + * If a constructor has a single argument of type 'T&&' (an 'rvalue reference + * to T'), that indicates that it is a 'move constructor'. That's 1). It should + * move, not copy, its argument into the object being constructed. It may leave + * the original in any safely-destructible state. + * + * If a constructor's argument is an rvalue, as in 'C(f(x))' or 'C(x + y)', as + * opposed to an lvalue, as in 'C(x)', then overload resolution will prefer the + * move constructor, if there is one. The 'mozilla::Move' function, defined in + * this file, is an identity function you can use in a constructor invocation to + * make any argument into an rvalue, like this: C(Move(x)). That's 2). (You + * could use any function that works, but 'Move' indicates your intention + * clearly.) + * + * Where we might define a copy constructor for a class C like this: + * + * C(const C& rhs) { ... copy rhs to this ... } + * + * we would declare a move constructor like this: + * + * C(C&& rhs) { .. move rhs to this ... } + * + * And where we might perform a copy like this: + * + * C c2(c1); + * + * we would perform a move like this: + * + * C c2(Move(c1)); + * + * Note that 'T&&' implicitly converts to 'T&'. So you can pass a 'T&&' to an + * ordinary copy constructor for a type that doesn't support a special move + * constructor, and you'll just get a copy. This means that templates can use + * Move whenever they know they won't use the original value any more, even if + * they're not sure whether the type at hand has a specialized move constructor. + * If it doesn't, the 'T&&' will just convert to a 'T&', and the ordinary copy + * constructor will apply. + * + * A class with a move constructor can also provide a move assignment operator. + * A generic definition would run this's destructor, and then apply the move + * constructor to *this's memory. A typical definition: + * + * C& operator=(C&& rhs) { + * MOZ_ASSERT(&rhs != this, "self-moves are prohibited"); + * this->~C(); + * new(this) C(Move(rhs)); + * return *this; + * } + * + * With that in place, one can write move assignments like this: + * + * c2 = Move(c1); + * + * This destroys c2, moves c1's value to c2, and leaves c1 in an undefined but + * destructible state. + * + * As we say, a move must leave the original in a "destructible" state. The + * original's destructor will still be called, so if a move doesn't + * actually steal all its resources, that's fine. We require only that the + * move destination must take on the original's value; and that destructing + * the original must not break the move destination. + * + * (Opinions differ on whether move assignment operators should deal with move + * assignment of an object onto itself. It seems wise to either handle that + * case, or assert that it does not occur.) + * + * Forwarding: + * + * Sometimes we want copy construction or assignment if we're passed an ordinary + * value, but move construction if passed an rvalue reference. For example, if + * our constructor takes two arguments and either could usefully be a move, it + * seems silly to write out all four combinations: + * + * C::C(X& x, Y& y) : x(x), y(y) { } + * C::C(X& x, Y&& y) : x(x), y(Move(y)) { } + * C::C(X&& x, Y& y) : x(Move(x)), y(y) { } + * C::C(X&& x, Y&& y) : x(Move(x)), y(Move(y)) { } + * + * To avoid this, C++11 has tweaks to make it possible to write what you mean. + * The four constructor overloads above can be written as one constructor + * template like so[0]: + * + * template <typename XArg, typename YArg> + * C::C(XArg&& x, YArg&& y) : x(Forward<XArg>(x)), y(Forward<YArg>(y)) { } + * + * ("'Don't Repeat Yourself'? What's that?") + * + * This takes advantage of two new rules in C++11: + * + * - First, when a function template takes an argument that is an rvalue + * reference to a template argument (like 'XArg&& x' and 'YArg&& y' above), + * then when the argument is applied to an lvalue, the template argument + * resolves to 'T&'; and when it is applied to an rvalue, the template + * argument resolves to 'T'. Thus, in a call to C::C like: + * + * X foo(int); + * Y yy; + * + * C(foo(5), yy) + * + * XArg would resolve to 'X', and YArg would resolve to 'Y&'. + * + * - Second, Whereas C++ used to forbid references to references, C++11 defines + * 'collapsing rules': 'T& &', 'T&& &', and 'T& &&' (that is, any combination + * involving an lvalue reference) now collapse to simply 'T&'; and 'T&& &&' + * collapses to 'T&&'. + * + * Thus, in the call above, 'XArg&&' is 'X&&'; and 'YArg&&' is 'Y& &&', which + * collapses to 'Y&'. Because the arguments are declared as rvalue references + * to template arguments, the lvalue-ness "shines through" where present. + * + * Then, the 'Forward<T>' function --- you must invoke 'Forward' with its type + * argument --- returns an lvalue reference or an rvalue reference to its + * argument, depending on what T is. In our unified constructor definition, that + * means that we'll invoke either the copy or move constructors for x and y, + * depending on what we gave C's constructor. In our call, we'll move 'foo()' + * into 'x', but copy 'yy' into 'y'. + * + * This header file defines Move and Forward in the mozilla namespace. It's up + * to individual containers to annotate moves as such, by calling Move; and it's + * up to individual types to define move constructors and assignment operators + * when valuable. + * + * (C++11 says that the <utility> header file should define 'std::move' and + * 'std::forward', which are just like our 'Move' and 'Forward'; but those + * definitions aren't available in that header on all our platforms, so we + * define them ourselves here.) + * + * 0. This pattern is known as "perfect forwarding". Interestingly, it is not + * actually perfect, and it can't forward all possible argument expressions! + * There is a C++11 issue: you can't form a reference to a bit-field. As a + * workaround, assign the bit-field to a local variable and use that: + * + * // C is as above + * struct S { int x : 1; } s; + * C(s.x, 0); // BAD: s.x is a reference to a bit-field, can't form those + * int tmp = s.x; + * C(tmp, 0); // OK: tmp not a bit-field + */ + +/** + * Identical to std::Move(); this is necessary until our stlport supports + * std::move(). + */ +template<typename T> +inline typename RemoveReference<T>::Type&& +Move(T&& aX) +{ + return static_cast<typename RemoveReference<T>::Type&&>(aX); +} + +/** + * These two overloads are identical to std::forward(); they are necessary until + * our stlport supports std::forward(). + */ +template<typename T> +inline T&& +Forward(typename RemoveReference<T>::Type& aX) +{ + return static_cast<T&&>(aX); +} + +template<typename T> +inline T&& +Forward(typename RemoveReference<T>::Type&& aX) +{ + static_assert(!IsLvalueReference<T>::value, + "misuse of Forward detected! try the other overload"); + return static_cast<T&&>(aX); +} + +/** Swap |aX| and |aY| using move-construction if possible. */ +template<typename T> +inline void +Swap(T& aX, T& aY) +{ + T tmp(Move(aX)); + aX = Move(aY); + aY = Move(tmp); +} + +} // namespace mozilla + +#endif /* mozilla_Move_h */ diff --git a/mfbt/NotNull.h b/mfbt/NotNull.h new file mode 100644 index 000000000..0c3c333e4 --- /dev/null +++ b/mfbt/NotNull.h @@ -0,0 +1,209 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef mozilla_NotNull_h +#define mozilla_NotNull_h + +// It's often unclear if a particular pointer, be it raw (T*) or smart +// (RefPtr<T>, nsCOMPtr<T>, etc.) can be null. This leads to missing null +// checks (which can cause crashes) and unnecessary null checks (which clutter +// the code). +// +// C++ has a built-in alternative that avoids these problems: references. This +// module defines another alternative, NotNull, which can be used in cases +// where references are not suitable. +// +// In the comments below we use the word "handle" to cover all varieties of +// pointers and references. +// +// References +// ---------- +// References are always non-null. (You can do |T& r = *p;| where |p| is null, +// but that's undefined behaviour. C++ doesn't provide any built-in, ironclad +// guarantee of non-nullness.) +// +// A reference works well when you need a temporary handle to an existing +// single object, e.g. for passing a handle to a function, or as a local handle +// within another object. (In Rust parlance, this is a "borrow".) +// +// A reference is less appropriate in the following cases. +// +// - As a primary handle to an object. E.g. code such as this is possible but +// strange: |T& t = *new T(); ...; delete &t;| +// +// - As a handle to an array. It's common for |T*| to refer to either a single +// |T| or an array of |T|, but |T&| cannot refer to an array of |T| because +// you can't index off a reference (at least, not without first converting it +// to a pointer). +// +// - When the handle identity is meaningful, e.g. if you have a hashtable of +// handles, because you have to use |&| on the reference to convert it to a +// pointer. +// +// - Some people don't like using non-const references as function parameters, +// because it is not clear at the call site that the argument might be +// modified. +// +// - When you need "smart" behaviour. E.g. we lack reference equivalents to +// RefPtr and nsCOMPtr. +// +// - When interfacing with code that uses pointers a lot, sometimes using a +// reference just feels like an odd fit. +// +// Furthermore, a reference is impossible in the following cases. +// +// - When the handle is rebound to another object. References don't allow this. +// +// - When the handle has type |void|. |void&| is not allowed. +// +// NotNull is an alternative that can be used in any of the above cases except +// for the last one, where the handle type is |void|. See below. + +#include "mozilla/Assertions.h" + +namespace mozilla { + +// NotNull can be used to wrap a "base" pointer (raw or smart) to indicate it +// is not null. Some examples: +// +// - NotNull<char*> +// - NotNull<RefPtr<Event>> +// - NotNull<nsCOMPtr<Event>> +// +// NotNull has the following notable properties. +// +// - It has zero space overhead. +// +// - It must be initialized explicitly. There is no default initialization. +// +// - It auto-converts to the base pointer type. +// +// - It does not auto-convert from a base pointer. Implicit conversion from a +// less-constrained type (e.g. T*) to a more-constrained type (e.g. +// NotNull<T*>) is dangerous. Creation and assignment from a base pointer can +// only be done with WrapNotNull(), which makes them impossible to overlook, +// both when writing and reading code. +// +// - When initialized (or assigned) it is checked, and if it is null we abort. +// This guarantees that it cannot be null. +// +// - |operator bool()| is deleted. This means you cannot check a NotNull in a +// boolean context, which eliminates the possibility of unnecessary null +// checks. +// +// NotNull currently doesn't work with UniquePtr. See +// https://github.com/Microsoft/GSL/issues/89 for some discussion. +// +template <typename T> +class NotNull +{ + template <typename U> friend NotNull<U> WrapNotNull(U aBasePtr); + + T mBasePtr; + + // This constructor is only used by WrapNotNull(). + template <typename U> + explicit NotNull(U aBasePtr) : mBasePtr(aBasePtr) {} + +public: + // Disallow default construction. + NotNull() = delete; + + // Construct/assign from another NotNull with a compatible base pointer type. + template <typename U> + MOZ_IMPLICIT NotNull(const NotNull<U>& aOther) : mBasePtr(aOther.get()) {} + + // Default copy/move construction and assignment. + NotNull(const NotNull<T>&) = default; + NotNull<T>& operator=(const NotNull<T>&) = default; + NotNull(NotNull<T>&&) = default; + NotNull<T>& operator=(NotNull<T>&&) = default; + + // Disallow null checks, which are unnecessary for this type. + explicit operator bool() const = delete; + + // Explicit conversion to a base pointer. Use only to resolve ambiguity or to + // get a castable pointer. + const T& get() const { return mBasePtr; } + + // Implicit conversion to a base pointer. Preferable to get(). + operator const T&() const { return get(); } + + // Dereference operators. + const T& operator->() const { return get(); } + decltype(*mBasePtr) operator*() const { return *mBasePtr; } +}; + +template <typename T> +NotNull<T> +WrapNotNull(const T aBasePtr) +{ + NotNull<T> notNull(aBasePtr); + MOZ_RELEASE_ASSERT(aBasePtr); + return notNull; +} + +// Compare two NotNulls. +template <typename T, typename U> +inline bool +operator==(const NotNull<T>& aLhs, const NotNull<U>& aRhs) +{ + return aLhs.get() == aRhs.get(); +} +template <typename T, typename U> +inline bool +operator!=(const NotNull<T>& aLhs, const NotNull<U>& aRhs) +{ + return aLhs.get() != aRhs.get(); +} + +// Compare a NotNull to a base pointer. +template <typename T, typename U> +inline bool +operator==(const NotNull<T>& aLhs, const U& aRhs) +{ + return aLhs.get() == aRhs; +} +template <typename T, typename U> +inline bool +operator!=(const NotNull<T>& aLhs, const U& aRhs) +{ + return aLhs.get() != aRhs; +} + +// Compare a base pointer to a NotNull. +template <typename T, typename U> +inline bool +operator==(const T& aLhs, const NotNull<U>& aRhs) +{ + return aLhs == aRhs.get(); +} +template <typename T, typename U> +inline bool +operator!=(const T& aLhs, const NotNull<U>& aRhs) +{ + return aLhs != aRhs.get(); +} + +// Disallow comparing a NotNull to a nullptr. +template <typename T> +bool +operator==(const NotNull<T>&, decltype(nullptr)) = delete; +template <typename T> +bool +operator!=(const NotNull<T>&, decltype(nullptr)) = delete; + +// Disallow comparing a nullptr to a NotNull. +template <typename T> +bool +operator==(decltype(nullptr), const NotNull<T>&) = delete; +template <typename T> +bool +operator!=(decltype(nullptr), const NotNull<T>&) = delete; + +} // namespace mozilla + +#endif /* mozilla_NotNull_h */ diff --git a/mfbt/NullPtr.h b/mfbt/NullPtr.h new file mode 100644 index 000000000..d2248f4bc --- /dev/null +++ b/mfbt/NullPtr.h @@ -0,0 +1,31 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Implements a mozilla::IsNullPointer<T> type trait. */ + +#ifndef mozilla_NullPtr_h +#define mozilla_NullPtr_h + +#include "mozilla/TypeTraits.h" + +namespace mozilla { + +/** + * IsNullPointer<T>::value is true iff T is decltype(nullptr). + * + * Ideally this would be in TypeTraits.h, but C++11 omitted std::is_null_pointer + * (fixed in C++14), so in the interests of easing a switch to <type_traits>, + * this trait lives elsewhere. + */ +template<typename T> +struct IsNullPointer : FalseType {}; + +template<> +struct IsNullPointer<decltype(nullptr)> : TrueType {}; + +} // namespace mozilla + +#endif /* mozilla_NullPtr_h */ diff --git a/mfbt/Opaque.h b/mfbt/Opaque.h new file mode 100644 index 000000000..d7239ee7c --- /dev/null +++ b/mfbt/Opaque.h @@ -0,0 +1,44 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* An opaque integral type supporting only comparison operators. */ + +#ifndef mozilla_Opaque_h +#define mozilla_Opaque_h + +#include "mozilla/TypeTraits.h" + +namespace mozilla { + +/** + * Opaque<T> is a replacement for integral T in cases where only comparisons + * must be supported, and it's desirable to prevent accidental dependency on + * exact values. + */ +template<typename T> +class Opaque final +{ + static_assert(mozilla::IsIntegral<T>::value, + "mozilla::Opaque only supports integral types"); + + T mValue; + +public: + Opaque() {} + explicit Opaque(T aValue) : mValue(aValue) {} + + bool operator==(const Opaque& aOther) const { + return mValue == aOther.mValue; + } + + bool operator!=(const Opaque& aOther) const { + return !(*this == aOther); + } +}; + +} // namespace mozilla + +#endif /* mozilla_Opaque_h */ diff --git a/mfbt/OperatorNewExtensions.h b/mfbt/OperatorNewExtensions.h new file mode 100644 index 000000000..52fd88a66 --- /dev/null +++ b/mfbt/OperatorNewExtensions.h @@ -0,0 +1,52 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* A version of |operator new| that eschews mandatory null-checks. */ + +#ifndef mozilla_OperatorNewExtensions_h +#define mozilla_OperatorNewExtensions_h + +#include "mozilla/Assertions.h" + +// Credit goes to WebKit for this implementation, cf. +// https://bugs.webkit.org/show_bug.cgi?id=74676 +namespace mozilla { +enum NotNullTag { + KnownNotNull, +}; +} // namespace mozilla + +/* + * The logic here is a little subtle. [expr.new] states that if the allocation + * function being called returns null, then object initialization must not be + * done, and the entirety of the new expression must return null. Non-throwing + * (noexcept) functions are defined to return null to indicate failure. The + * standard placement operator new is defined in such a way, and so it requires + * a null check, even when that null check would be extraneous. Functions + * declared without such a specification are defined to throw std::bad_alloc if + * they fail, and return a non-null pointer otherwise. We compile without + * exceptions, so any placement new overload we define that doesn't declare + * itself as noexcept must therefore avoid generating a null check. Below is + * just such an overload. + * + * You might think that MOZ_NONNULL might perform the same function, but + * MOZ_NONNULL isn't supported on all of our compilers, and even when it is + * supported, doesn't work on all the versions we support. And even keeping + * those limitations in mind, we can't put MOZ_NONNULL on the global, + * standardized placement new function in any event. + * + * We deliberately don't add MOZ_NONNULL(3) to tag |p| as non-null, to benefit + * hypothetical static analyzers. Doing so makes |MOZ_ASSERT(p)|'s internal + * test vacuous, and some compilers warn about such vacuous tests. + */ +inline void* +operator new(size_t, mozilla::NotNullTag, void* p) +{ + MOZ_ASSERT(p); + return p; +} + +#endif // mozilla_OperatorNewExtensions_h diff --git a/mfbt/Pair.h b/mfbt/Pair.h new file mode 100644 index 000000000..ad7b86a29 --- /dev/null +++ b/mfbt/Pair.h @@ -0,0 +1,219 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* A class holding a pair of objects that tries to conserve storage space. */ + +#ifndef mozilla_Pair_h +#define mozilla_Pair_h + +#include "mozilla/Attributes.h" +#include "mozilla/Move.h" +#include "mozilla/TypeTraits.h" + +namespace mozilla { + +namespace detail { + +enum StorageType { AsBase, AsMember }; + +// Optimize storage using the Empty Base Optimization -- that empty base classes +// don't take up space -- to optimize size when one or the other class is +// stateless and can be used as a base class. +// +// The extra conditions on storage for B are necessary so that PairHelper won't +// ambiguously inherit from either A or B, such that one or the other base class +// would be inaccessible. +template<typename A, typename B, + detail::StorageType = + IsEmpty<A>::value ? detail::AsBase : detail::AsMember, + detail::StorageType = + IsEmpty<B>::value && !IsBaseOf<A, B>::value && !IsBaseOf<B, A>::value + ? detail::AsBase + : detail::AsMember> +struct PairHelper; + +template<typename A, typename B> +struct PairHelper<A, B, AsMember, AsMember> +{ +protected: + template<typename AArg, typename BArg> + PairHelper(AArg&& aA, BArg&& aB) + : mFirstA(Forward<AArg>(aA)), + mSecondB(Forward<BArg>(aB)) + {} + + A& first() { return mFirstA; } + const A& first() const { return mFirstA; } + B& second() { return mSecondB; } + const B& second() const { return mSecondB; } + + void swap(PairHelper& aOther) + { + Swap(mFirstA, aOther.mFirstA); + Swap(mSecondB, aOther.mSecondB); + } + +private: + A mFirstA; + B mSecondB; +}; + +template<typename A, typename B> +struct PairHelper<A, B, AsMember, AsBase> : private B +{ +protected: + template<typename AArg, typename BArg> + PairHelper(AArg&& aA, BArg&& aB) + : B(Forward<BArg>(aB)), + mFirstA(Forward<AArg>(aA)) + {} + + A& first() { return mFirstA; } + const A& first() const { return mFirstA; } + B& second() { return *this; } + const B& second() const { return *this; } + + void swap(PairHelper& aOther) + { + Swap(mFirstA, aOther.mFirstA); + Swap(static_cast<B&>(*this), static_cast<B&>(aOther)); + } + +private: + A mFirstA; +}; + +template<typename A, typename B> +struct PairHelper<A, B, AsBase, AsMember> : private A +{ +protected: + template<typename AArg, typename BArg> + PairHelper(AArg&& aA, BArg&& aB) + : A(Forward<AArg>(aA)), + mSecondB(Forward<BArg>(aB)) + {} + + A& first() { return *this; } + const A& first() const { return *this; } + B& second() { return mSecondB; } + const B& second() const { return mSecondB; } + + void swap(PairHelper& aOther) + { + Swap(static_cast<A&>(*this), static_cast<A&>(aOther)); + Swap(mSecondB, aOther.mSecondB); + } + +private: + B mSecondB; +}; + +template<typename A, typename B> +struct PairHelper<A, B, AsBase, AsBase> : private A, private B +{ +protected: + template<typename AArg, typename BArg> + PairHelper(AArg&& aA, BArg&& aB) + : A(Forward<AArg>(aA)), + B(Forward<BArg>(aB)) + {} + + A& first() { return static_cast<A&>(*this); } + const A& first() const { return static_cast<A&>(*this); } + B& second() { return static_cast<B&>(*this); } + const B& second() const { return static_cast<B&>(*this); } + + void swap(PairHelper& aOther) + { + Swap(static_cast<A&>(*this), static_cast<A&>(aOther)); + Swap(static_cast<B&>(*this), static_cast<B&>(aOther)); + } +}; + +} // namespace detail + +/** + * Pair is the logical concatenation of an instance of A with an instance B. + * Space is conserved when possible. Neither A nor B may be a final class. + * + * It's typically clearer to have individual A and B member fields. Except if + * you want the space-conserving qualities of Pair, you're probably better off + * not using this! + * + * No guarantees are provided about the memory layout of A and B, the order of + * initialization or destruction of A and B, and so on. (This is approximately + * required to optimize space usage.) The first/second names are merely + * conceptual! + */ +template<typename A, typename B> +struct Pair + : private detail::PairHelper<A, B> +{ + typedef typename detail::PairHelper<A, B> Base; + +public: + template<typename AArg, typename BArg> + Pair(AArg&& aA, BArg&& aB) + : Base(Forward<AArg>(aA), Forward<BArg>(aB)) + {} + + Pair(Pair&& aOther) + : Base(Move(aOther.first()), Move(aOther.second())) + { } + + Pair(const Pair& aOther) = default; + + Pair& operator=(Pair&& aOther) + { + MOZ_ASSERT(this != &aOther, "Self-moves are prohibited"); + + first() = Move(aOther.first()); + second() = Move(aOther.second()); + + return *this; + } + + Pair& operator=(const Pair& aOther) = default; + + /** The A instance. */ + using Base::first; + /** The B instance. */ + using Base::second; + + /** Swap this pair with another pair. */ + void swap(Pair& aOther) { Base::swap(aOther); } +}; + +template<typename A, class B> +void +Swap(Pair<A, B>& aX, Pair<A, B>& aY) +{ + aX.swap(aY); +} + +/** + * MakePair allows you to construct a Pair instance using type inference. A call + * like this: + * + * MakePair(Foo(), Bar()) + * + * will return a Pair<Foo, Bar>. + */ +template<typename A, typename B> +Pair<typename RemoveCV<typename RemoveReference<A>::Type>::Type, + typename RemoveCV<typename RemoveReference<B>::Type>::Type> +MakePair(A&& aA, B&& aB) +{ + return + Pair<typename RemoveCV<typename RemoveReference<A>::Type>::Type, + typename RemoveCV<typename RemoveReference<B>::Type>::Type>( + Forward<A>(aA), + Forward<B>(aB)); +} + +} // namespace mozilla + +#endif /* mozilla_Pair_h */ diff --git a/mfbt/PodOperations.h b/mfbt/PodOperations.h new file mode 100644 index 000000000..e6f4df21e --- /dev/null +++ b/mfbt/PodOperations.h @@ -0,0 +1,196 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* + * Operations for zeroing POD types, arrays, and so on. + * + * These operations are preferable to memset, memcmp, and the like because they + * don't require remembering to multiply by sizeof(T), array lengths, and so on + * everywhere. + */ + +#ifndef mozilla_PodOperations_h +#define mozilla_PodOperations_h + +#include "mozilla/Array.h" +#include "mozilla/ArrayUtils.h" +#include "mozilla/Attributes.h" + +#include <stdint.h> +#include <string.h> + +namespace mozilla { + +/** Set the contents of |aT| to 0. */ +template<typename T> +static MOZ_ALWAYS_INLINE void +PodZero(T* aT) +{ + memset(aT, 0, sizeof(T)); +} + +/** Set the contents of |aNElem| elements starting at |aT| to 0. */ +template<typename T> +static MOZ_ALWAYS_INLINE void +PodZero(T* aT, size_t aNElem) +{ + /* + * This function is often called with 'aNElem' small; we use an inline loop + * instead of calling 'memset' with a non-constant length. The compiler + * should inline the memset call with constant size, though. + */ + for (T* end = aT + aNElem; aT < end; aT++) { + memset(aT, 0, sizeof(T)); + } +} + +/* + * Arrays implicitly convert to pointers to their first element, which is + * dangerous when combined with the above PodZero definitions. Adding an + * overload for arrays is ambiguous, so we need another identifier. The + * ambiguous overload is left to catch mistaken uses of PodZero; if you get a + * compile error involving PodZero and array types, use PodArrayZero instead. + */ +template<typename T, size_t N> +static void PodZero(T (&aT)[N]) = delete; +template<typename T, size_t N> +static void PodZero(T (&aT)[N], size_t aNElem) = delete; + +/** Set the contents of the array |aT| to zero. */ +template <class T, size_t N> +static MOZ_ALWAYS_INLINE void +PodArrayZero(T (&aT)[N]) +{ + memset(aT, 0, N * sizeof(T)); +} + +template <typename T, size_t N> +static MOZ_ALWAYS_INLINE void +PodArrayZero(Array<T, N>& aArr) +{ + memset(&aArr[0], 0, N * sizeof(T)); +} + +/** + * Assign |*aSrc| to |*aDst|. The locations must not be the same and must not + * overlap. + */ +template<typename T> +static MOZ_ALWAYS_INLINE void +PodAssign(T* aDst, const T* aSrc) +{ + MOZ_ASSERT(aDst + 1 <= aSrc || aSrc + 1 <= aDst, + "destination and source must not overlap"); + memcpy(reinterpret_cast<char*>(aDst), reinterpret_cast<const char*>(aSrc), + sizeof(T)); +} + +/** + * Copy |aNElem| T elements from |aSrc| to |aDst|. The two memory ranges must + * not overlap! + */ +template<typename T> +static MOZ_ALWAYS_INLINE void +PodCopy(T* aDst, const T* aSrc, size_t aNElem) +{ + MOZ_ASSERT(aDst + aNElem <= aSrc || aSrc + aNElem <= aDst, + "destination and source must not overlap"); + if (aNElem < 128) { + /* + * Avoid using operator= in this loop, as it may have been + * intentionally deleted by the POD type. + */ + for (const T* srcend = aSrc + aNElem; aSrc < srcend; aSrc++, aDst++) { + PodAssign(aDst, aSrc); + } + } else { + memcpy(aDst, aSrc, aNElem * sizeof(T)); + } +} + +template<typename T> +static MOZ_ALWAYS_INLINE void +PodCopy(volatile T* aDst, const volatile T* aSrc, size_t aNElem) +{ + MOZ_ASSERT(aDst + aNElem <= aSrc || aSrc + aNElem <= aDst, + "destination and source must not overlap"); + + /* + * Volatile |aDst| requires extra work, because it's undefined behavior to + * modify volatile objects using the mem* functions. Just write out the + * loops manually, using operator= rather than memcpy for the same reason, + * and let the compiler optimize to the extent it can. + */ + for (const volatile T* srcend = aSrc + aNElem; + aSrc < srcend; + aSrc++, aDst++) { + *aDst = *aSrc; + } +} + +/* + * Copy the contents of the array |aSrc| into the array |aDst|, both of size N. + * The arrays must not overlap! + */ +template <class T, size_t N> +static MOZ_ALWAYS_INLINE void +PodArrayCopy(T (&aDst)[N], const T (&aSrc)[N]) +{ + PodCopy(aDst, aSrc, N); +} + +/** + * Copy the memory for |aNElem| T elements from |aSrc| to |aDst|. If the two + * memory ranges overlap, then the effect is as if the |aNElem| elements are + * first copied from |aSrc| to a temporary array, and then from the temporary + * array to |aDst|. + */ +template<typename T> +static MOZ_ALWAYS_INLINE void +PodMove(T* aDst, const T* aSrc, size_t aNElem) +{ + MOZ_ASSERT(aNElem <= SIZE_MAX / sizeof(T), + "trying to move an impossible number of elements"); + memmove(aDst, aSrc, aNElem * sizeof(T)); +} + +/** + * Determine whether the |len| elements at |one| are memory-identical to the + * |len| elements at |two|. + */ +template<typename T> +static MOZ_ALWAYS_INLINE bool +PodEqual(const T* one, const T* two, size_t len) +{ + if (len < 128) { + const T* p1end = one + len; + const T* p1 = one; + const T* p2 = two; + for (; p1 < p1end; p1++, p2++) { + if (*p1 != *p2) { + return false; + } + } + return true; + } + + return !memcmp(one, two, len * sizeof(T)); +} + +/* + * Determine whether the |N| elements at |one| are memory-identical to the + * |N| elements at |two|. + */ +template <class T, size_t N> +static MOZ_ALWAYS_INLINE bool +PodEqual(const T (&one)[N], const T (&two)[N]) +{ + return PodEqual(one, two, N); +} + +} // namespace mozilla + +#endif /* mozilla_PodOperations_h */ diff --git a/mfbt/Poison.cpp b/mfbt/Poison.cpp new file mode 100644 index 000000000..b2767011d --- /dev/null +++ b/mfbt/Poison.cpp @@ -0,0 +1,208 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* + * A poison value that can be used to fill a memory space with + * an address that leads to a safe crash when dereferenced. + */ + +#include "mozilla/Poison.h" + +#include "mozilla/Assertions.h" +#ifdef _WIN32 +# include <windows.h> +#elif !defined(__OS2__) +# include <unistd.h> +# include <sys/mman.h> +# ifndef MAP_ANON +# ifdef MAP_ANONYMOUS +# define MAP_ANON MAP_ANONYMOUS +# else +# error "Don't know how to get anonymous memory" +# endif +# endif +#endif + +extern "C" { +uintptr_t gMozillaPoisonValue; +uintptr_t gMozillaPoisonBase; +uintptr_t gMozillaPoisonSize; +} + +// Freed memory is filled with a poison value, which we arrange to +// form a pointer either to an always-unmapped region of the address +// space, or to a page that has been reserved and rendered +// inaccessible via OS primitives. See tests/TestPoisonArea.cpp for +// extensive discussion of the requirements for this page. The code +// from here to 'class FreeList' needs to be kept in sync with that +// file. + +#ifdef _WIN32 +static void* +ReserveRegion(uintptr_t aRegion, uintptr_t aSize) +{ + return VirtualAlloc((void*)aRegion, aSize, MEM_RESERVE, PAGE_NOACCESS); +} + +static void +ReleaseRegion(void* aRegion, uintptr_t aSize) +{ + VirtualFree(aRegion, aSize, MEM_RELEASE); +} + +static bool +ProbeRegion(uintptr_t aRegion, uintptr_t aSize) +{ + SYSTEM_INFO sinfo; + GetSystemInfo(&sinfo); + if (aRegion >= (uintptr_t)sinfo.lpMaximumApplicationAddress && + aRegion + aSize >= (uintptr_t)sinfo.lpMaximumApplicationAddress) { + return true; + } else { + return false; + } +} + +static uintptr_t +GetDesiredRegionSize() +{ + SYSTEM_INFO sinfo; + GetSystemInfo(&sinfo); + return sinfo.dwAllocationGranularity; +} + +#define RESERVE_FAILED 0 + +#elif defined(__OS2__) +static void* +ReserveRegion(uintptr_t aRegion, uintptr_t aSize) +{ + // OS/2 doesn't support allocation at an arbitrary address, + // so return an address that is known to be invalid. + return (void*)0xFFFD0000; +} + +static void +ReleaseRegion(void* aRegion, uintptr_t aSize) +{ + return; +} + +static bool +ProbeRegion(uintptr_t aRegion, uintptr_t aSize) +{ + // There's no reliable way to probe an address in the system + // arena other than by touching it and seeing if a trap occurs. + return false; +} + +static uintptr_t +GetDesiredRegionSize() +{ + // Page size is fixed at 4k. + return 0x1000; +} + +#define RESERVE_FAILED 0 + +#else // Unix + +#include "mozilla/TaggedAnonymousMemory.h" + +static void* +ReserveRegion(uintptr_t aRegion, uintptr_t aSize) +{ + return MozTaggedAnonymousMmap(reinterpret_cast<void*>(aRegion), aSize, + PROT_NONE, MAP_PRIVATE|MAP_ANON, -1, 0, + "poison"); +} + +static void +ReleaseRegion(void* aRegion, uintptr_t aSize) +{ + munmap(aRegion, aSize); +} + +static bool +ProbeRegion(uintptr_t aRegion, uintptr_t aSize) +{ + if (madvise(reinterpret_cast<void*>(aRegion), aSize, MADV_NORMAL)) { + return true; + } else { + return false; + } +} + +static uintptr_t +GetDesiredRegionSize() +{ + return sysconf(_SC_PAGESIZE); +} + +#define RESERVE_FAILED MAP_FAILED + +#endif // system dependencies + +static_assert(sizeof(uintptr_t) == 4 || sizeof(uintptr_t) == 8, ""); +static_assert(sizeof(uintptr_t) == sizeof(void*), ""); + +static uintptr_t +ReservePoisonArea(uintptr_t rgnsize) +{ + if (sizeof(uintptr_t) == 8) { + // Use the hardware-inaccessible region. + // We have to avoid 64-bit constants and shifts by 32 bits, since this + // code is compiled in 32-bit mode, although it is never executed there. + return + (((uintptr_t(0x7FFFFFFFu) << 31) << 1 | uintptr_t(0xF0DEAFFFu)) + & ~(rgnsize-1)); + } + + // First see if we can allocate the preferred poison address from the OS. + uintptr_t candidate = (0xF0DEAFFF & ~(rgnsize-1)); + void* result = ReserveRegion(candidate, rgnsize); + if (result == (void*)candidate) { + // success - inaccessible page allocated + return candidate; + } + + // That didn't work, so see if the preferred address is within a range + // of permanently inacessible memory. + if (ProbeRegion(candidate, rgnsize)) { + // success - selected page cannot be usable memory + if (result != RESERVE_FAILED) { + ReleaseRegion(result, rgnsize); + } + return candidate; + } + + // The preferred address is already in use. Did the OS give us a + // consolation prize? + if (result != RESERVE_FAILED) { + return uintptr_t(result); + } + + // It didn't, so try to allocate again, without any constraint on + // the address. + result = ReserveRegion(0, rgnsize); + if (result != RESERVE_FAILED) { + return uintptr_t(result); + } + + MOZ_CRASH("no usable poison region identified"); +} + +void +mozPoisonValueInit() +{ + gMozillaPoisonSize = GetDesiredRegionSize(); + gMozillaPoisonBase = ReservePoisonArea(gMozillaPoisonSize); + + if (gMozillaPoisonSize == 0) { // can't happen + return; + } + gMozillaPoisonValue = gMozillaPoisonBase + gMozillaPoisonSize / 2 - 1; +} diff --git a/mfbt/Poison.h b/mfbt/Poison.h new file mode 100644 index 000000000..aae567654 --- /dev/null +++ b/mfbt/Poison.h @@ -0,0 +1,108 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* + * A poison value that can be used to fill a memory space with + * an address that leads to a safe crash when dereferenced. + */ + +#ifndef mozilla_Poison_h +#define mozilla_Poison_h + +#include "mozilla/Assertions.h" +#include "mozilla/Types.h" + +#include <stdint.h> + +MOZ_BEGIN_EXTERN_C + +extern MFBT_DATA uintptr_t gMozillaPoisonValue; + +/** + * @return the poison value. + */ +inline uintptr_t mozPoisonValue() +{ + return gMozillaPoisonValue; +} + +/** + * Overwrite the memory block of aSize bytes at aPtr with the poison value. + * aPtr MUST be aligned at a sizeof(uintptr_t) boundary. + * Only an even number of sizeof(uintptr_t) bytes are overwritten, the last + * few bytes (if any) is not overwritten. + */ +inline void mozWritePoison(void* aPtr, size_t aSize) +{ + const uintptr_t POISON = mozPoisonValue(); + char* p = (char*)aPtr; + char* limit = p + aSize; + MOZ_ASSERT((uintptr_t)aPtr % sizeof(uintptr_t) == 0, "bad alignment"); + MOZ_ASSERT(aSize >= sizeof(uintptr_t), "poisoning this object has no effect"); + for (; p < limit; p += sizeof(uintptr_t)) { + *((uintptr_t*)p) = POISON; + } +} + +/** + * Initialize the poison value. + * This should only be called once. + */ +extern MFBT_API void mozPoisonValueInit(); + +/* Values annotated by CrashReporter */ +extern MFBT_DATA uintptr_t gMozillaPoisonBase; +extern MFBT_DATA uintptr_t gMozillaPoisonSize; + +MOZ_END_EXTERN_C + +#if defined(__cplusplus) + +namespace mozilla { + +/** + * This class is designed to cause crashes when various kinds of memory + * corruption are observed. For instance, let's say we have a class C where we + * suspect out-of-bounds writes to some members. We can insert a member of type + * Poison near the members we suspect are being corrupted by out-of-bounds + * writes. Or perhaps we have a class K we suspect is subject to use-after-free + * violations, in which case it doesn't particularly matter where in the class + * we add the member of type Poison. + * + * In either case, we then insert calls to Check() throughout the code. Doing + * so enables us to narrow down the location where the corruption is occurring. + * A pleasant side-effect of these additional Check() calls is that crash + * signatures may become more regular, as crashes will ideally occur + * consolidated at the point of a Check(), rather than scattered about at + * various uses of the corrupted memory. + */ +class CorruptionCanary { +public: + CorruptionCanary() { + mValue = kCanarySet; + } + + ~CorruptionCanary() { + Check(); + mValue = mozPoisonValue(); + } + + void Check() const { + if (mValue != kCanarySet) { + MOZ_CRASH("Canary check failed, check lifetime"); + } + } + +private: + static const uintptr_t kCanarySet = 0x0f0b0f0b; + uintptr_t mValue; +}; + +} // mozilla + +#endif + +#endif /* mozilla_Poison_h */ diff --git a/mfbt/Range.h b/mfbt/Range.h new file mode 100644 index 000000000..47d91bb0c --- /dev/null +++ b/mfbt/Range.h @@ -0,0 +1,58 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef mozilla_Range_h +#define mozilla_Range_h + +#include "mozilla/RangedPtr.h" +#include "mozilla/TypeTraits.h" + +#include <stddef.h> + +namespace mozilla { + +// Range<T> is a tuple containing a pointer and a length. +template <typename T> +class Range +{ + const RangedPtr<T> mStart; + const RangedPtr<T> mEnd; + +public: + Range() : mStart(nullptr, 0), mEnd(nullptr, 0) {} + Range(T* aPtr, size_t aLength) + : mStart(aPtr, aPtr, aPtr + aLength), + mEnd(aPtr + aLength, aPtr, aPtr + aLength) + {} + Range(const RangedPtr<T>& aStart, const RangedPtr<T>& aEnd) + : mStart(aStart.get(), aStart.get(), aEnd.get()), + mEnd(aEnd.get(), aStart.get(), aEnd.get()) + { + // Only accept two RangedPtrs within the same range. + aStart.checkIdenticalRange(aEnd); + MOZ_ASSERT(aStart <= aEnd); + } + + template<typename U, + class = typename EnableIf<IsConvertible<U (*)[], T (*)[]>::value, + int>::Type> + MOZ_IMPLICIT Range(const Range<U>& aOther) + : mStart(aOther.mStart), + mEnd(aOther.mEnd) + {} + + RangedPtr<T> begin() const { return mStart; } + RangedPtr<T> end() const { return mEnd; } + size_t length() const { return mEnd - mStart; } + + T& operator[](size_t aOffset) const { return mStart[aOffset]; } + + explicit operator bool() const { return mStart != nullptr; } +}; + +} // namespace mozilla + +#endif /* mozilla_Range_h */ diff --git a/mfbt/RangedArray.h b/mfbt/RangedArray.h new file mode 100644 index 000000000..afe6267ff --- /dev/null +++ b/mfbt/RangedArray.h @@ -0,0 +1,66 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* + * A compile-time constant-length array, with bounds-checking assertions -- but + * unlike mozilla::Array, with indexes biased by a constant. + * + * Thus where mozilla::Array<int, 3> is a three-element array indexed by [0, 3), + * mozilla::RangedArray<int, 8, 3> is a three-element array indexed by [8, 11). + */ + +#ifndef mozilla_RangedArray_h +#define mozilla_RangedArray_h + +#include "mozilla/Array.h" + +namespace mozilla { + +template<typename T, size_t MinIndex, size_t Length> +class RangedArray +{ +private: + typedef Array<T, Length> ArrayType; + ArrayType mArr; + +public: + T& operator[](size_t aIndex) + { + MOZ_ASSERT(aIndex == MinIndex || aIndex > MinIndex); + return mArr[aIndex - MinIndex]; + } + + const T& operator[](size_t aIndex) const + { + MOZ_ASSERT(aIndex == MinIndex || aIndex > MinIndex); + return mArr[aIndex - MinIndex]; + } + + typedef typename ArrayType::iterator iterator; + typedef typename ArrayType::const_iterator const_iterator; + typedef typename ArrayType::reverse_iterator reverse_iterator; + typedef typename ArrayType::const_reverse_iterator const_reverse_iterator; + + // Methods for range-based for loops. + iterator begin() { return mArr.begin(); } + const_iterator begin() const { return mArr.begin(); } + const_iterator cbegin() const { return mArr.cbegin(); } + iterator end() { return mArr.end(); } + const_iterator end() const { return mArr.end(); } + const_iterator cend() const { return mArr.cend(); } + + // Methods for reverse iterating. + reverse_iterator rbegin() { return mArr.rbegin(); } + const_reverse_iterator rbegin() const { return mArr.rbegin(); } + const_reverse_iterator crbegin() const { return mArr.crbegin(); } + reverse_iterator rend() { return mArr.rend(); } + const_reverse_iterator rend() const { return mArr.rend(); } + const_reverse_iterator crend() const { return mArr.crend(); } +}; + +} // namespace mozilla + +#endif // mozilla_RangedArray_h diff --git a/mfbt/RangedPtr.h b/mfbt/RangedPtr.h new file mode 100644 index 000000000..a07c1f4f8 --- /dev/null +++ b/mfbt/RangedPtr.h @@ -0,0 +1,292 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* + * Implements a smart pointer asserted to remain within a range specified at + * construction. + */ + +#ifndef mozilla_RangedPtr_h +#define mozilla_RangedPtr_h + +#include "mozilla/ArrayUtils.h" +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" + +#include <stdint.h> + +namespace mozilla { + +/* + * RangedPtr is a smart pointer restricted to an address range specified at + * creation. The pointer (and any smart pointers derived from it) must remain + * within the range [start, end] (inclusive of end to facilitate use as + * sentinels). Dereferencing or indexing into the pointer (or pointers derived + * from it) must remain within the range [start, end). All the standard pointer + * operators are defined on it; in debug builds these operations assert that the + * range specified at construction is respected. + * + * In theory passing a smart pointer instance as an argument can be slightly + * slower than passing a T* (due to ABI requirements for passing structs versus + * passing pointers), if the method being called isn't inlined. If you are in + * extremely performance-critical code, you may want to be careful using this + * smart pointer as an argument type. + * + * RangedPtr<T> intentionally does not implicitly convert to T*. Use get() to + * explicitly convert to T*. Keep in mind that the raw pointer of course won't + * implement bounds checking in debug builds. + */ +template<typename T> +class RangedPtr +{ + T* mPtr; + +#ifdef DEBUG + T* const mRangeStart; + T* const mRangeEnd; +#endif + + void checkSanity() + { + MOZ_ASSERT(mRangeStart <= mPtr); + MOZ_ASSERT(mPtr <= mRangeEnd); + } + + /* Creates a new pointer for |aPtr|, restricted to this pointer's range. */ + RangedPtr<T> create(T* aPtr) const + { +#ifdef DEBUG + return RangedPtr<T>(aPtr, mRangeStart, mRangeEnd); +#else + return RangedPtr<T>(aPtr, nullptr, size_t(0)); +#endif + } + + uintptr_t asUintptr() const { return reinterpret_cast<uintptr_t>(mPtr); } + +public: + RangedPtr(T* aPtr, T* aStart, T* aEnd) + : mPtr(aPtr) +#ifdef DEBUG + , mRangeStart(aStart), mRangeEnd(aEnd) +#endif + { + MOZ_ASSERT(mRangeStart <= mRangeEnd); + checkSanity(); + } + RangedPtr(T* aPtr, T* aStart, size_t aLength) + : mPtr(aPtr) +#ifdef DEBUG + , mRangeStart(aStart), mRangeEnd(aStart + aLength) +#endif + { + MOZ_ASSERT(aLength <= size_t(-1) / sizeof(T)); + MOZ_ASSERT(reinterpret_cast<uintptr_t>(mRangeStart) + aLength * sizeof(T) >= + reinterpret_cast<uintptr_t>(mRangeStart)); + checkSanity(); + } + + /* Equivalent to RangedPtr(aPtr, aPtr, aLength). */ + RangedPtr(T* aPtr, size_t aLength) + : mPtr(aPtr) +#ifdef DEBUG + , mRangeStart(aPtr), mRangeEnd(aPtr + aLength) +#endif + { + MOZ_ASSERT(aLength <= size_t(-1) / sizeof(T)); + MOZ_ASSERT(reinterpret_cast<uintptr_t>(mRangeStart) + aLength * sizeof(T) >= + reinterpret_cast<uintptr_t>(mRangeStart)); + checkSanity(); + } + + /* Equivalent to RangedPtr(aArr, aArr, N). */ + template<size_t N> + explicit RangedPtr(T (&aArr)[N]) + : mPtr(aArr) +#ifdef DEBUG + , mRangeStart(aArr), mRangeEnd(aArr + N) +#endif + { + checkSanity(); + } + + T* get() const { return mPtr; } + + explicit operator bool() const { return mPtr != nullptr; } + + void checkIdenticalRange(const RangedPtr<T>& aOther) const + { + MOZ_ASSERT(mRangeStart == aOther.mRangeStart); + MOZ_ASSERT(mRangeEnd == aOther.mRangeEnd); + } + + /* + * You can only assign one RangedPtr into another if the two pointers have + * the same valid range: + * + * char arr1[] = "hi"; + * char arr2[] = "bye"; + * RangedPtr<char> p1(arr1, 2); + * p1 = RangedPtr<char>(arr1 + 1, arr1, arr1 + 2); // works + * p1 = RangedPtr<char>(arr2, 3); // asserts + */ + RangedPtr<T>& operator=(const RangedPtr<T>& aOther) + { + checkIdenticalRange(aOther); + mPtr = aOther.mPtr; + checkSanity(); + return *this; + } + + RangedPtr<T> operator+(size_t aInc) const + { + MOZ_ASSERT(aInc <= size_t(-1) / sizeof(T)); + MOZ_ASSERT(asUintptr() + aInc * sizeof(T) >= asUintptr()); + return create(mPtr + aInc); + } + + RangedPtr<T> operator-(size_t aDec) const + { + MOZ_ASSERT(aDec <= size_t(-1) / sizeof(T)); + MOZ_ASSERT(asUintptr() - aDec * sizeof(T) <= asUintptr()); + return create(mPtr - aDec); + } + + /* + * You can assign a raw pointer into a RangedPtr if the raw pointer is + * within the range specified at creation. + */ + template <typename U> + RangedPtr<T>& operator=(U* aPtr) + { + *this = create(aPtr); + return *this; + } + + template <typename U> + RangedPtr<T>& operator=(const RangedPtr<U>& aPtr) + { + MOZ_ASSERT(mRangeStart <= aPtr.mPtr); + MOZ_ASSERT(aPtr.mPtr <= mRangeEnd); + mPtr = aPtr.mPtr; + checkSanity(); + return *this; + } + + RangedPtr<T>& operator++() + { + return (*this += 1); + } + + RangedPtr<T> operator++(int) + { + RangedPtr<T> rcp = *this; + ++*this; + return rcp; + } + + RangedPtr<T>& operator--() + { + return (*this -= 1); + } + + RangedPtr<T> operator--(int) + { + RangedPtr<T> rcp = *this; + --*this; + return rcp; + } + + RangedPtr<T>& operator+=(size_t aInc) + { + *this = *this + aInc; + return *this; + } + + RangedPtr<T>& operator-=(size_t aDec) + { + *this = *this - aDec; + return *this; + } + + T& operator[](int aIndex) const + { + MOZ_ASSERT(size_t(aIndex > 0 ? aIndex : -aIndex) <= size_t(-1) / sizeof(T)); + return *create(mPtr + aIndex); + } + + T& operator*() const + { + MOZ_ASSERT(mPtr >= mRangeStart); + MOZ_ASSERT(mPtr < mRangeEnd); + return *mPtr; + } + + T* operator->() const + { + MOZ_ASSERT(mPtr >= mRangeStart); + MOZ_ASSERT(mPtr < mRangeEnd); + return mPtr; + } + + template <typename U> + bool operator==(const RangedPtr<U>& aOther) const + { + return mPtr == aOther.mPtr; + } + template <typename U> + bool operator!=(const RangedPtr<U>& aOther) const + { + return !(*this == aOther); + } + + template<typename U> + bool operator==(const U* u) const + { + return mPtr == u; + } + template<typename U> + bool operator!=(const U* u) const + { + return !(*this == u); + } + + template <typename U> + bool operator<(const RangedPtr<U>& aOther) const + { + return mPtr < aOther.mPtr; + } + template <typename U> + bool operator<=(const RangedPtr<U>& aOther) const + { + return mPtr <= aOther.mPtr; + } + + template <typename U> + bool operator>(const RangedPtr<U>& aOther) const + { + return mPtr > aOther.mPtr; + } + template <typename U> + bool operator>=(const RangedPtr<U>& aOther) const + { + return mPtr >= aOther.mPtr; + } + + size_t operator-(const RangedPtr<T>& aOther) const + { + MOZ_ASSERT(mPtr >= aOther.mPtr); + return PointerRangeSize(aOther.mPtr, mPtr); + } + +private: + RangedPtr() = delete; + T* operator&() = delete; +}; + +} /* namespace mozilla */ + +#endif /* mozilla_RangedPtr_h */ diff --git a/mfbt/ReentrancyGuard.h b/mfbt/ReentrancyGuard.h new file mode 100644 index 000000000..9963974e7 --- /dev/null +++ b/mfbt/ReentrancyGuard.h @@ -0,0 +1,57 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Small helper class for asserting uses of a class are non-reentrant. */ + +#ifndef mozilla_ReentrancyGuard_h +#define mozilla_ReentrancyGuard_h + +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" +#include "mozilla/GuardObjects.h" + +namespace mozilla { + +/* Useful for implementing containers that assert non-reentrancy */ +class MOZ_RAII ReentrancyGuard +{ + MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER +#ifdef DEBUG + bool& mEntered; +#endif + +public: + template<class T> +#ifdef DEBUG + explicit ReentrancyGuard(T& aObj + MOZ_GUARD_OBJECT_NOTIFIER_PARAM) + : mEntered(aObj.mEntered) +#else + explicit ReentrancyGuard(T& + MOZ_GUARD_OBJECT_NOTIFIER_PARAM) +#endif + { + MOZ_GUARD_OBJECT_NOTIFIER_INIT; +#ifdef DEBUG + MOZ_ASSERT(!mEntered); + mEntered = true; +#endif + } + ~ReentrancyGuard() + { +#ifdef DEBUG + mEntered = false; +#endif + } + +private: + ReentrancyGuard(const ReentrancyGuard&) = delete; + void operator=(const ReentrancyGuard&) = delete; +}; + +} // namespace mozilla + +#endif /* mozilla_ReentrancyGuard_h */ diff --git a/mfbt/RefCountType.h b/mfbt/RefCountType.h new file mode 100644 index 000000000..e95a22a0c --- /dev/null +++ b/mfbt/RefCountType.h @@ -0,0 +1,37 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef mozilla_RefCountType_h +#define mozilla_RefCountType_h + +#include <stdint.h> + +/** + * MozRefCountType is Mozilla's reference count type. + * + * We use the same type to represent the refcount of RefCounted objects + * as well, in order to be able to use the leak detection facilities + * that are implemented by XPCOM. + * + * Note that this type is not in the mozilla namespace so that it is + * usable for both C and C++ code. + */ +typedef uintptr_t MozRefCountType; + +/* + * This is the return type for AddRef() and Release() in nsISupports. + * IUnknown of COM returns an unsigned long from equivalent functions. + * + * The following ifdef exists to maintain binary compatibility with + * IUnknown, the base interface in Microsoft COM. + */ +#ifdef XP_WIN +typedef unsigned long MozExternalRefCountType; +#else +typedef uint32_t MozExternalRefCountType; +#endif + +#endif diff --git a/mfbt/RefCounted.h b/mfbt/RefCounted.h new file mode 100644 index 000000000..ae05f1e0f --- /dev/null +++ b/mfbt/RefCounted.h @@ -0,0 +1,210 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* CRTP refcounting templates. Do not use unless you are an Expert. */ + +#ifndef mozilla_RefCounted_h +#define mozilla_RefCounted_h + +#include "mozilla/AlreadyAddRefed.h" +#include "mozilla/Assertions.h" +#include "mozilla/Atomics.h" +#include "mozilla/Attributes.h" +#include "mozilla/Move.h" +#include "mozilla/RefCountType.h" +#include "mozilla/TypeTraits.h" + +#if defined(MOZILLA_INTERNAL_API) +#include "nsXPCOM.h" +#endif + +#if defined(MOZILLA_INTERNAL_API) && \ + (defined(DEBUG) || defined(FORCE_BUILD_REFCNT_LOGGING)) +#define MOZ_REFCOUNTED_LEAK_CHECKING +#endif + +namespace mozilla { + +/** + * RefCounted<T> is a sort of a "mixin" for a class T. RefCounted + * manages, well, refcounting for T, and because RefCounted is + * parameterized on T, RefCounted<T> can call T's destructor directly. + * This means T doesn't need to have a virtual dtor and so doesn't + * need a vtable. + * + * RefCounted<T> is created with refcount == 0. Newly-allocated + * RefCounted<T> must immediately be assigned to a RefPtr to make the + * refcount > 0. It's an error to allocate and free a bare + * RefCounted<T>, i.e. outside of the RefPtr machinery. Attempts to + * do so will abort DEBUG builds. + * + * Live RefCounted<T> have refcount > 0. The lifetime (refcounts) of + * live RefCounted<T> are controlled by RefPtr<T> and + * RefPtr<super/subclass of T>. Upon a transition from refcounted==1 + * to 0, the RefCounted<T> "dies" and is destroyed. The "destroyed" + * state is represented in DEBUG builds by refcount==0xffffdead. This + * state distinguishes use-before-ref (refcount==0) from + * use-after-destroy (refcount==0xffffdead). + * + * Note that when deriving from RefCounted or AtomicRefCounted, you + * should add MOZ_DECLARE_REFCOUNTED_TYPENAME(ClassName) to the public + * section of your class, where ClassName is the name of your class. + */ +namespace detail { +const MozRefCountType DEAD = 0xffffdead; + +// When building code that gets compiled into Gecko, try to use the +// trace-refcount leak logging facilities. +#ifdef MOZ_REFCOUNTED_LEAK_CHECKING +class RefCountLogger +{ +public: + static void logAddRef(const void* aPointer, MozRefCountType aRefCount, + const char* aTypeName, uint32_t aInstanceSize) + { + MOZ_ASSERT(aRefCount != DEAD); + NS_LogAddRef(const_cast<void*>(aPointer), aRefCount, aTypeName, + aInstanceSize); + } + + static void logRelease(const void* aPointer, MozRefCountType aRefCount, + const char* aTypeName) + { + MOZ_ASSERT(aRefCount != DEAD); + NS_LogRelease(const_cast<void*>(aPointer), aRefCount, aTypeName); + } +}; +#endif + +// This is used WeakPtr.h as well as this file. +enum RefCountAtomicity +{ + AtomicRefCount, + NonAtomicRefCount +}; + +template<typename T, RefCountAtomicity Atomicity> +class RefCounted +{ +protected: + RefCounted() : mRefCnt(0) {} + ~RefCounted() { MOZ_ASSERT(mRefCnt == detail::DEAD); } + +public: + // Compatibility with nsRefPtr. + void AddRef() const + { + // Note: this method must be thread safe for AtomicRefCounted. + MOZ_ASSERT(int32_t(mRefCnt) >= 0); +#ifndef MOZ_REFCOUNTED_LEAK_CHECKING + ++mRefCnt; +#else + const char* type = static_cast<const T*>(this)->typeName(); + uint32_t size = static_cast<const T*>(this)->typeSize(); + const void* ptr = static_cast<const T*>(this); + MozRefCountType cnt = ++mRefCnt; + detail::RefCountLogger::logAddRef(ptr, cnt, type, size); +#endif + } + + void Release() const + { + // Note: this method must be thread safe for AtomicRefCounted. + MOZ_ASSERT(int32_t(mRefCnt) > 0); +#ifndef MOZ_REFCOUNTED_LEAK_CHECKING + MozRefCountType cnt = --mRefCnt; +#else + const char* type = static_cast<const T*>(this)->typeName(); + const void* ptr = static_cast<const T*>(this); + MozRefCountType cnt = --mRefCnt; + // Note: it's not safe to touch |this| after decrementing the refcount, + // except for below. + detail::RefCountLogger::logRelease(ptr, cnt, type); +#endif + if (0 == cnt) { + // Because we have atomically decremented the refcount above, only + // one thread can get a 0 count here, so as long as we can assume that + // everything else in the system is accessing this object through + // RefPtrs, it's safe to access |this| here. +#ifdef DEBUG + mRefCnt = detail::DEAD; +#endif + delete static_cast<const T*>(this); + } + } + + // Compatibility with wtf::RefPtr. + void ref() { AddRef(); } + void deref() { Release(); } + MozRefCountType refCount() const { return mRefCnt; } + bool hasOneRef() const + { + MOZ_ASSERT(mRefCnt > 0); + return mRefCnt == 1; + } + +private: + mutable typename Conditional<Atomicity == AtomicRefCount, + Atomic<MozRefCountType>, + MozRefCountType>::Type mRefCnt; +}; + +#ifdef MOZ_REFCOUNTED_LEAK_CHECKING +// Passing override for the optional argument marks the typeName and +// typeSize functions defined by this macro as overrides. +#define MOZ_DECLARE_REFCOUNTED_VIRTUAL_TYPENAME(T, ...) \ + virtual const char* typeName() const __VA_ARGS__ { return #T; } \ + virtual size_t typeSize() const __VA_ARGS__ { return sizeof(*this); } +#else +#define MOZ_DECLARE_REFCOUNTED_VIRTUAL_TYPENAME(T, ...) +#endif + +// Note that this macro is expanded unconditionally because it declares only +// two small inline functions which will hopefully get eliminated by the linker +// in non-leak-checking builds. +#define MOZ_DECLARE_REFCOUNTED_TYPENAME(T) \ + const char* typeName() const { return #T; } \ + size_t typeSize() const { return sizeof(*this); } + +} // namespace detail + +template<typename T> +class RefCounted : public detail::RefCounted<T, detail::NonAtomicRefCount> +{ +public: + ~RefCounted() + { + static_assert(IsBaseOf<RefCounted, T>::value, + "T must derive from RefCounted<T>"); + } +}; + +namespace external { + +/** + * AtomicRefCounted<T> is like RefCounted<T>, with an atomically updated + * reference counter. + * + * NOTE: Please do not use this class, use NS_INLINE_DECL_THREADSAFE_REFCOUNTING + * instead. + */ +template<typename T> +class AtomicRefCounted : + public mozilla::detail::RefCounted<T, mozilla::detail::AtomicRefCount> +{ +public: + ~AtomicRefCounted() + { + static_assert(IsBaseOf<AtomicRefCounted, T>::value, + "T must derive from AtomicRefCounted<T>"); + } +}; + +} // namespace external + +} // namespace mozilla + +#endif // mozilla_RefCounted_h diff --git a/mfbt/RefPtr.h b/mfbt/RefPtr.h new file mode 100644 index 000000000..bfa8f6e02 --- /dev/null +++ b/mfbt/RefPtr.h @@ -0,0 +1,656 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef mozilla_RefPtr_h +#define mozilla_RefPtr_h + +#include "mozilla/AlreadyAddRefed.h" +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" + +/*****************************************************************************/ + +// template <class T> class RefPtrGetterAddRefs; + +class nsCOMPtr_helper; + +namespace mozilla { +template<class T> class OwningNonNull; +template<class T> class StaticRefPtr; + +// Traditionally, RefPtr supports automatic refcounting of any pointer type +// with AddRef() and Release() methods that follow the traditional semantics. +// +// This traits class can be specialized to operate on other pointer types. For +// example, we specialize this trait for opaque FFI types that represent +// refcounted objects in Rust. +// +// Given the use of ConstRemovingRefPtrTraits below, U should not be a const- +// qualified type. +template<class U> +struct RefPtrTraits +{ + static void AddRef(U* aPtr) { + aPtr->AddRef(); + } + static void Release(U* aPtr) { + aPtr->Release(); + } +}; + +} // namespace mozilla + +template <class T> +class RefPtr +{ +private: + void + assign_with_AddRef(T* aRawPtr) + { + if (aRawPtr) { + ConstRemovingRefPtrTraits<T>::AddRef(aRawPtr); + } + assign_assuming_AddRef(aRawPtr); + } + + void + assign_assuming_AddRef(T* aNewPtr) + { + T* oldPtr = mRawPtr; + mRawPtr = aNewPtr; + if (oldPtr) { + ConstRemovingRefPtrTraits<T>::Release(oldPtr); + } + } + +private: + T* MOZ_OWNING_REF mRawPtr; + +public: + typedef T element_type; + + ~RefPtr() + { + if (mRawPtr) { + ConstRemovingRefPtrTraits<T>::Release(mRawPtr); + } + } + + // Constructors + + RefPtr() + : mRawPtr(nullptr) + // default constructor + { + } + + RefPtr(const RefPtr<T>& aSmartPtr) + : mRawPtr(aSmartPtr.mRawPtr) + // copy-constructor + { + if (mRawPtr) { + ConstRemovingRefPtrTraits<T>::AddRef(mRawPtr); + } + } + + RefPtr(RefPtr<T>&& aRefPtr) + : mRawPtr(aRefPtr.mRawPtr) + { + aRefPtr.mRawPtr = nullptr; + } + + // construct from a raw pointer (of the right type) + + MOZ_IMPLICIT RefPtr(T* aRawPtr) + : mRawPtr(aRawPtr) + { + if (mRawPtr) { + ConstRemovingRefPtrTraits<T>::AddRef(mRawPtr); + } + } + + MOZ_IMPLICIT RefPtr(decltype(nullptr)) + : mRawPtr(nullptr) + { + } + + template <typename I> + MOZ_IMPLICIT RefPtr(already_AddRefed<I>& aSmartPtr) + : mRawPtr(aSmartPtr.take()) + // construct from |already_AddRefed| + { + } + + template <typename I> + MOZ_IMPLICIT RefPtr(already_AddRefed<I>&& aSmartPtr) + : mRawPtr(aSmartPtr.take()) + // construct from |otherRefPtr.forget()| + { + } + + template <typename I> + MOZ_IMPLICIT RefPtr(const RefPtr<I>& aSmartPtr) + : mRawPtr(aSmartPtr.get()) + // copy-construct from a smart pointer with a related pointer type + { + if (mRawPtr) { + ConstRemovingRefPtrTraits<T>::AddRef(mRawPtr); + } + } + + template <typename I> + MOZ_IMPLICIT RefPtr(RefPtr<I>&& aSmartPtr) + : mRawPtr(aSmartPtr.forget().take()) + // construct from |Move(RefPtr<SomeSubclassOfT>)|. + { + } + + MOZ_IMPLICIT RefPtr(const nsCOMPtr_helper& aHelper); + + // Defined in OwningNonNull.h + template<class U> + MOZ_IMPLICIT RefPtr(const mozilla::OwningNonNull<U>& aOther); + + // Defined in StaticPtr.h + template<class U> + MOZ_IMPLICIT RefPtr(const mozilla::StaticRefPtr<U>& aOther); + + // Assignment operators + + RefPtr<T>& + operator=(decltype(nullptr)) + { + assign_assuming_AddRef(nullptr); + return *this; + } + + RefPtr<T>& + operator=(const RefPtr<T>& aRhs) + // copy assignment operator + { + assign_with_AddRef(aRhs.mRawPtr); + return *this; + } + + template <typename I> + RefPtr<T>& + operator=(const RefPtr<I>& aRhs) + // assign from an RefPtr of a related pointer type + { + assign_with_AddRef(aRhs.get()); + return *this; + } + + RefPtr<T>& + operator=(T* aRhs) + // assign from a raw pointer (of the right type) + { + assign_with_AddRef(aRhs); + return *this; + } + + template <typename I> + RefPtr<T>& + operator=(already_AddRefed<I>& aRhs) + // assign from |already_AddRefed| + { + assign_assuming_AddRef(aRhs.take()); + return *this; + } + + template <typename I> + RefPtr<T>& + operator=(already_AddRefed<I> && aRhs) + // assign from |otherRefPtr.forget()| + { + assign_assuming_AddRef(aRhs.take()); + return *this; + } + + RefPtr<T>& operator=(const nsCOMPtr_helper& aHelper); + + RefPtr<T>& + operator=(RefPtr<T> && aRefPtr) + { + assign_assuming_AddRef(aRefPtr.mRawPtr); + aRefPtr.mRawPtr = nullptr; + return *this; + } + + // Defined in OwningNonNull.h + template<class U> + RefPtr<T>& + operator=(const mozilla::OwningNonNull<U>& aOther); + + // Defined in StaticPtr.h + template<class U> + RefPtr<T>& + operator=(const mozilla::StaticRefPtr<U>& aOther); + + // Other pointer operators + + void + swap(RefPtr<T>& aRhs) + // ...exchange ownership with |aRhs|; can save a pair of refcount operations + { + T* temp = aRhs.mRawPtr; + aRhs.mRawPtr = mRawPtr; + mRawPtr = temp; + } + + void + swap(T*& aRhs) + // ...exchange ownership with |aRhs|; can save a pair of refcount operations + { + T* temp = aRhs; + aRhs = mRawPtr; + mRawPtr = temp; + } + + already_AddRefed<T> + forget() + // return the value of mRawPtr and null out mRawPtr. Useful for + // already_AddRefed return values. + { + T* temp = nullptr; + swap(temp); + return already_AddRefed<T>(temp); + } + + template <typename I> + void + forget(I** aRhs) + // Set the target of aRhs to the value of mRawPtr and null out mRawPtr. + // Useful to avoid unnecessary AddRef/Release pairs with "out" + // parameters where aRhs bay be a T** or an I** where I is a base class + // of T. + { + MOZ_ASSERT(aRhs, "Null pointer passed to forget!"); + *aRhs = mRawPtr; + mRawPtr = nullptr; + } + + T* + get() const + /* + Prefer the implicit conversion provided automatically by |operator T*() const|. + Use |get()| to resolve ambiguity or to get a castable pointer. + */ + { + return const_cast<T*>(mRawPtr); + } + + operator T*() const +#ifdef MOZ_HAVE_REF_QUALIFIERS + & +#endif + /* + ...makes an |RefPtr| act like its underlying raw pointer type whenever it + is used in a context where a raw pointer is expected. It is this operator + that makes an |RefPtr| substitutable for a raw pointer. + + Prefer the implicit use of this operator to calling |get()|, except where + necessary to resolve ambiguity. + */ + { + return get(); + } + +#ifdef MOZ_HAVE_REF_QUALIFIERS + // Don't allow implicit conversion of temporary RefPtr to raw pointer, + // because the refcount might be one and the pointer will immediately become + // invalid. + operator T*() const && = delete; + + // These are needed to avoid the deleted operator above. XXX Why is operator! + // needed separately? Shouldn't the compiler prefer using the non-deleted + // operator bool instead of the deleted operator T*? + explicit operator bool() const { return !!mRawPtr; } + bool operator!() const { return !mRawPtr; } +#endif + + T* + operator->() const MOZ_NO_ADDREF_RELEASE_ON_RETURN + { + MOZ_ASSERT(mRawPtr != nullptr, + "You can't dereference a NULL RefPtr with operator->()."); + return get(); + } + + template <typename R, typename... Args> + class Proxy + { + typedef R (T::*member_function)(Args...); + T* mRawPtr; + member_function mFunction; + public: + Proxy(T* aRawPtr, member_function aFunction) + : mRawPtr(aRawPtr), + mFunction(aFunction) + { + } + template<typename... ActualArgs> + R operator()(ActualArgs&&... aArgs) + { + return ((*mRawPtr).*mFunction)(mozilla::Forward<ActualArgs>(aArgs)...); + } + }; + + template <typename R, typename... Args> + Proxy<R, Args...> operator->*(R (T::*aFptr)(Args...)) const + { + MOZ_ASSERT(mRawPtr != nullptr, + "You can't dereference a NULL RefPtr with operator->*()."); + return Proxy<R, Args...>(get(), aFptr); + } + + RefPtr<T>* + get_address() + // This is not intended to be used by clients. See |address_of| + // below. + { + return this; + } + + const RefPtr<T>* + get_address() const + // This is not intended to be used by clients. See |address_of| + // below. + { + return this; + } + +public: + T& + operator*() const + { + MOZ_ASSERT(mRawPtr != nullptr, + "You can't dereference a NULL RefPtr with operator*()."); + return *get(); + } + + T** + StartAssignment() + { + assign_assuming_AddRef(nullptr); + return reinterpret_cast<T**>(&mRawPtr); + } +private: + // This helper class makes |RefPtr<const T>| possible by casting away + // the constness from the pointer when calling AddRef() and Release(). + // + // This is necessary because AddRef() and Release() implementations can't + // generally expected to be const themselves (without heavy use of |mutable| + // and |const_cast| in their own implementations). + // + // This should be sound because while |RefPtr<const T>| provides a + // const view of an object, the object itself should not be const (it + // would have to be allocated as |new const T| or similar to be const). + template<class U> + struct ConstRemovingRefPtrTraits + { + static void AddRef(U* aPtr) { + mozilla::RefPtrTraits<U>::AddRef(aPtr); + } + static void Release(U* aPtr) { + mozilla::RefPtrTraits<U>::Release(aPtr); + } + }; + template<class U> + struct ConstRemovingRefPtrTraits<const U> + { + static void AddRef(const U* aPtr) { + mozilla::RefPtrTraits<U>::AddRef(const_cast<U*>(aPtr)); + } + static void Release(const U* aPtr) { + mozilla::RefPtrTraits<U>::Release(const_cast<U*>(aPtr)); + } + }; +}; + +class nsCycleCollectionTraversalCallback; +template <typename T> +void +CycleCollectionNoteChild(nsCycleCollectionTraversalCallback& aCallback, + T* aChild, const char* aName, uint32_t aFlags); + +template <typename T> +inline void +ImplCycleCollectionUnlink(RefPtr<T>& aField) +{ + aField = nullptr; +} + +template <typename T> +inline void +ImplCycleCollectionTraverse(nsCycleCollectionTraversalCallback& aCallback, + RefPtr<T>& aField, + const char* aName, + uint32_t aFlags = 0) +{ + CycleCollectionNoteChild(aCallback, aField.get(), aName, aFlags); +} + +template <class T> +inline RefPtr<T>* +address_of(RefPtr<T>& aPtr) +{ + return aPtr.get_address(); +} + +template <class T> +inline const RefPtr<T>* +address_of(const RefPtr<T>& aPtr) +{ + return aPtr.get_address(); +} + +template <class T> +class RefPtrGetterAddRefs +/* + ... + + This class is designed to be used for anonymous temporary objects in the + argument list of calls that return COM interface pointers, e.g., + + RefPtr<IFoo> fooP; + ...->GetAddRefedPointer(getter_AddRefs(fooP)) + + DO NOT USE THIS TYPE DIRECTLY IN YOUR CODE. Use |getter_AddRefs()| instead. + + When initialized with a |RefPtr|, as in the example above, it returns + a |void**|, a |T**|, or an |nsISupports**| as needed, that the + outer call (|GetAddRefedPointer| in this case) can fill in. + + This type should be a nested class inside |RefPtr<T>|. +*/ +{ +public: + explicit + RefPtrGetterAddRefs(RefPtr<T>& aSmartPtr) + : mTargetSmartPtr(aSmartPtr) + { + // nothing else to do + } + + operator void**() + { + return reinterpret_cast<void**>(mTargetSmartPtr.StartAssignment()); + } + + operator T**() + { + return mTargetSmartPtr.StartAssignment(); + } + + T*& + operator*() + { + return *(mTargetSmartPtr.StartAssignment()); + } + +private: + RefPtr<T>& mTargetSmartPtr; +}; + +template <class T> +inline RefPtrGetterAddRefs<T> +getter_AddRefs(RefPtr<T>& aSmartPtr) +/* + Used around a |RefPtr| when + ...makes the class |RefPtrGetterAddRefs<T>| invisible. +*/ +{ + return RefPtrGetterAddRefs<T>(aSmartPtr); +} + + +// Comparing two |RefPtr|s + +template <class T, class U> +inline bool +operator==(const RefPtr<T>& aLhs, const RefPtr<U>& aRhs) +{ + return static_cast<const T*>(aLhs.get()) == static_cast<const U*>(aRhs.get()); +} + + +template <class T, class U> +inline bool +operator!=(const RefPtr<T>& aLhs, const RefPtr<U>& aRhs) +{ + return static_cast<const T*>(aLhs.get()) != static_cast<const U*>(aRhs.get()); +} + + +// Comparing an |RefPtr| to a raw pointer + +template <class T, class U> +inline bool +operator==(const RefPtr<T>& aLhs, const U* aRhs) +{ + return static_cast<const T*>(aLhs.get()) == static_cast<const U*>(aRhs); +} + +template <class T, class U> +inline bool +operator==(const U* aLhs, const RefPtr<T>& aRhs) +{ + return static_cast<const U*>(aLhs) == static_cast<const T*>(aRhs.get()); +} + +template <class T, class U> +inline bool +operator!=(const RefPtr<T>& aLhs, const U* aRhs) +{ + return static_cast<const T*>(aLhs.get()) != static_cast<const U*>(aRhs); +} + +template <class T, class U> +inline bool +operator!=(const U* aLhs, const RefPtr<T>& aRhs) +{ + return static_cast<const U*>(aLhs) != static_cast<const T*>(aRhs.get()); +} + +template <class T, class U> +inline bool +operator==(const RefPtr<T>& aLhs, U* aRhs) +{ + return static_cast<const T*>(aLhs.get()) == const_cast<const U*>(aRhs); +} + +template <class T, class U> +inline bool +operator==(U* aLhs, const RefPtr<T>& aRhs) +{ + return const_cast<const U*>(aLhs) == static_cast<const T*>(aRhs.get()); +} + +template <class T, class U> +inline bool +operator!=(const RefPtr<T>& aLhs, U* aRhs) +{ + return static_cast<const T*>(aLhs.get()) != const_cast<const U*>(aRhs); +} + +template <class T, class U> +inline bool +operator!=(U* aLhs, const RefPtr<T>& aRhs) +{ + return const_cast<const U*>(aLhs) != static_cast<const T*>(aRhs.get()); +} + +// Comparing an |RefPtr| to |nullptr| + +template <class T> +inline bool +operator==(const RefPtr<T>& aLhs, decltype(nullptr)) +{ + return aLhs.get() == nullptr; +} + +template <class T> +inline bool +operator==(decltype(nullptr), const RefPtr<T>& aRhs) +{ + return nullptr == aRhs.get(); +} + +template <class T> +inline bool +operator!=(const RefPtr<T>& aLhs, decltype(nullptr)) +{ + return aLhs.get() != nullptr; +} + +template <class T> +inline bool +operator!=(decltype(nullptr), const RefPtr<T>& aRhs) +{ + return nullptr != aRhs.get(); +} + +/*****************************************************************************/ + +template <class T> +inline already_AddRefed<T> +do_AddRef(T* aObj) +{ + RefPtr<T> ref(aObj); + return ref.forget(); +} + +template <class T> +inline already_AddRefed<T> +do_AddRef(const RefPtr<T>& aObj) +{ + RefPtr<T> ref(aObj); + return ref.forget(); +} + +namespace mozilla { + +/** + * Helper function to be able to conveniently write things like: + * + * already_AddRefed<T> + * f(...) + * { + * return MakeAndAddRef<T>(...); + * } + */ +template<typename T, typename... Args> +already_AddRefed<T> +MakeAndAddRef(Args&&... aArgs) +{ + RefPtr<T> p(new T(Forward<Args>(aArgs)...)); + return p.forget(); +} + +} // namespace mozilla + +#endif /* mozilla_RefPtr_h */ diff --git a/mfbt/ReverseIterator.h b/mfbt/ReverseIterator.h new file mode 100644 index 000000000..49c2e2792 --- /dev/null +++ b/mfbt/ReverseIterator.h @@ -0,0 +1,168 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* An iterator that acts like another iterator, but iterating in + * the negative direction. (Note that not all iterators can iterate + * in the negative direction.) */ + +#ifndef mozilla_ReverseIterator_h +#define mozilla_ReverseIterator_h + +#include "mozilla/Attributes.h" +#include "mozilla/TypeTraits.h" + +namespace mozilla { + +template<typename IteratorT> +class ReverseIterator +{ +public: + template<typename Iterator> + explicit ReverseIterator(Iterator aIter) + : mCurrent(aIter) { } + + template<typename Iterator> + MOZ_IMPLICIT ReverseIterator(const ReverseIterator<Iterator>& aOther) + : mCurrent(aOther.mCurrent) { } + + decltype(*DeclVal<IteratorT>()) operator*() const + { + IteratorT tmp = mCurrent; + return *--tmp; + } + + /* Increments and decrements operators */ + + ReverseIterator& operator++() { --mCurrent; return *this; } + ReverseIterator& operator--() { ++mCurrent; return *this; } + ReverseIterator operator++(int) { auto ret = *this; mCurrent--; return ret; } + ReverseIterator operator--(int) { auto ret = *this; mCurrent++; return ret; } + + /* Comparison operators */ + + template<typename Iterator1, typename Iterator2> + friend bool operator==(const ReverseIterator<Iterator1>& aIter1, + const ReverseIterator<Iterator2>& aIter2); + template<typename Iterator1, typename Iterator2> + friend bool operator!=(const ReverseIterator<Iterator1>& aIter1, + const ReverseIterator<Iterator2>& aIter2); + template<typename Iterator1, typename Iterator2> + friend bool operator<(const ReverseIterator<Iterator1>& aIter1, + const ReverseIterator<Iterator2>& aIter2); + template<typename Iterator1, typename Iterator2> + friend bool operator<=(const ReverseIterator<Iterator1>& aIter1, + const ReverseIterator<Iterator2>& aIter2); + template<typename Iterator1, typename Iterator2> + friend bool operator>(const ReverseIterator<Iterator1>& aIter1, + const ReverseIterator<Iterator2>& aIter2); + template<typename Iterator1, typename Iterator2> + friend bool operator>=(const ReverseIterator<Iterator1>& aIter1, + const ReverseIterator<Iterator2>& aIter2); + +private: + IteratorT mCurrent; +}; + +template<typename Iterator1, typename Iterator2> +bool +operator==(const ReverseIterator<Iterator1>& aIter1, + const ReverseIterator<Iterator2>& aIter2) +{ + return aIter1.mCurrent == aIter2.mCurrent; +} + +template<typename Iterator1, typename Iterator2> +bool +operator!=(const ReverseIterator<Iterator1>& aIter1, + const ReverseIterator<Iterator2>& aIter2) +{ + return aIter1.mCurrent != aIter2.mCurrent; +} + +template<typename Iterator1, typename Iterator2> +bool +operator<(const ReverseIterator<Iterator1>& aIter1, + const ReverseIterator<Iterator2>& aIter2) +{ + return aIter1.mCurrent > aIter2.mCurrent; +} + +template<typename Iterator1, typename Iterator2> +bool +operator<=(const ReverseIterator<Iterator1>& aIter1, + const ReverseIterator<Iterator2>& aIter2) +{ + return aIter1.mCurrent >= aIter2.mCurrent; +} + +template<typename Iterator1, typename Iterator2> +bool +operator>(const ReverseIterator<Iterator1>& aIter1, + const ReverseIterator<Iterator2>& aIter2) +{ + return aIter1.mCurrent < aIter2.mCurrent; +} + +template<typename Iterator1, typename Iterator2> +bool +operator>=(const ReverseIterator<Iterator1>& aIter1, + const ReverseIterator<Iterator2>& aIter2) +{ + return aIter1.mCurrent <= aIter2.mCurrent; +} + +namespace detail { + +template<typename IteratorT> +class IteratorRange +{ +public: + typedef IteratorT iterator; + typedef IteratorT const_iterator; + typedef ReverseIterator<IteratorT> reverse_iterator; + typedef ReverseIterator<IteratorT> const_reverse_iterator; + + template<typename Iterator1, typename Iterator2> + MOZ_IMPLICIT IteratorRange(Iterator1 aIterBegin, Iterator2 aIterEnd) + : mIterBegin(aIterBegin), mIterEnd(aIterEnd) { } + + template<typename Iterator> + MOZ_IMPLICIT IteratorRange(const IteratorRange<Iterator>& aOther) + : mIterBegin(aOther.mIterBegin), mIterEnd(aOther.mIterEnd) { } + + iterator begin() const { return mIterBegin; } + const_iterator cbegin() const { return begin(); } + iterator end() const { return mIterEnd; } + const_iterator cend() const { return end(); } + reverse_iterator rbegin() const { return reverse_iterator(mIterEnd); } + const_reverse_iterator crbegin() const { return rbegin(); } + reverse_iterator rend() const { return reverse_iterator(mIterBegin); } + const_reverse_iterator crend() const { return rend(); } + +private: + IteratorT mIterBegin; + IteratorT mIterEnd; +}; + +} // namespace detail + +template<typename Range> +detail::IteratorRange<typename Range::reverse_iterator> +Reversed(Range& aRange) +{ + return {aRange.rbegin(), aRange.rend()}; +} + +template<typename Range> +detail::IteratorRange<typename Range::const_reverse_iterator> +Reversed(const Range& aRange) +{ + return {aRange.rbegin(), aRange.rend()}; +} + +} // namespace mozilla + +#endif // mozilla_ReverseIterator_h diff --git a/mfbt/RollingMean.h b/mfbt/RollingMean.h new file mode 100644 index 000000000..8cc3148e9 --- /dev/null +++ b/mfbt/RollingMean.h @@ -0,0 +1,115 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* A set abstraction for enumeration values. */ + +#ifndef mozilla_RollingMean_h_ +#define mozilla_RollingMean_h_ + +#include "mozilla/Assertions.h" +#include "mozilla/TypeTraits.h" +#include "mozilla/Vector.h" + +#include <stddef.h> + +namespace mozilla { + +/** + * RollingMean<T> calculates a rolling mean of the values it is given. It + * accumulates the total as values are added and removed. The second type + * argument S specifies the type of the total. This may need to be a bigger + * type in order to maintain that the sum of all values in the average doesn't + * exceed the maximum input value. + * + * WARNING: Float types are not supported due to rounding errors. + */ +template<typename T, typename S> +class RollingMean +{ +private: + size_t mInsertIndex; + size_t mMaxValues; + Vector<T> mValues; + S mTotal; + +public: + static_assert(!IsFloatingPoint<T>::value, + "floating-point types are unsupported due to rounding " + "errors"); + + explicit RollingMean(size_t aMaxValues) + : mInsertIndex(0), + mMaxValues(aMaxValues), + mTotal(0) + { + MOZ_ASSERT(aMaxValues > 0); + } + + RollingMean& operator=(RollingMean&& aOther) + { + MOZ_ASSERT(this != &aOther, "self-assignment is forbidden"); + this->~RollingMean(); + new(this) RollingMean(aOther.mMaxValues); + mInsertIndex = aOther.mInsertIndex; + mTotal = aOther.mTotal; + mValues.swap(aOther.mValues); + return *this; + } + + /** + * Insert a value into the rolling mean. + */ + bool insert(T aValue) + { + MOZ_ASSERT(mValues.length() <= mMaxValues); + + if (mValues.length() == mMaxValues) { + mTotal = mTotal - mValues[mInsertIndex] + aValue; + mValues[mInsertIndex] = aValue; + } else { + if (!mValues.append(aValue)) { + return false; + } + mTotal = mTotal + aValue; + } + + mInsertIndex = (mInsertIndex + 1) % mMaxValues; + return true; + } + + /** + * Calculate the rolling mean. + */ + T mean() + { + MOZ_ASSERT(!empty()); + return T(mTotal / int64_t(mValues.length())); + } + + bool empty() + { + return mValues.empty(); + } + + /** + * Remove all values from the rolling mean. + */ + void clear() + { + mValues.clear(); + mInsertIndex = 0; + mTotal = T(0); + } + + size_t maxValues() + { + return mMaxValues; + } +}; + +} // namespace mozilla + +#endif // mozilla_RollingMean_h_ diff --git a/mfbt/SHA1.cpp b/mfbt/SHA1.cpp new file mode 100644 index 000000000..f8968c3e1 --- /dev/null +++ b/mfbt/SHA1.cpp @@ -0,0 +1,333 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/EndianUtils.h" +#include "mozilla/SHA1.h" + +#include <string.h> + +using mozilla::NativeEndian; +using mozilla::SHA1Sum; + +static inline uint32_t +SHA_ROTL(uint32_t aT, uint32_t aN) +{ + MOZ_ASSERT(aN < 32); + return (aT << aN) | (aT >> (32 - aN)); +} + +static void +shaCompress(volatile unsigned* aX, const uint32_t* aBuf); + +#define SHA_F1(X, Y, Z) ((((Y) ^ (Z)) & (X)) ^ (Z)) +#define SHA_F2(X, Y, Z) ((X) ^ (Y) ^ (Z)) +#define SHA_F3(X, Y, Z) (((X) & (Y)) | ((Z) & ((X) | (Y)))) +#define SHA_F4(X, Y, Z) ((X) ^ (Y) ^ (Z)) + +#define SHA_MIX(n, a, b, c) XW(n) = SHA_ROTL(XW(a) ^ XW(b) ^ XW(c) ^XW(n), 1) + +SHA1Sum::SHA1Sum() + : mSize(0), mDone(false) +{ + // Initialize H with constants from FIPS180-1. + mH[0] = 0x67452301L; + mH[1] = 0xefcdab89L; + mH[2] = 0x98badcfeL; + mH[3] = 0x10325476L; + mH[4] = 0xc3d2e1f0L; +} + +/* + * Explanation of H array and index values: + * + * The context's H array is actually the concatenation of two arrays + * defined by SHA1, the H array of state variables (5 elements), + * and the W array of intermediate values, of which there are 16 elements. + * The W array starts at H[5], that is W[0] is H[5]. + * Although these values are defined as 32-bit values, we use 64-bit + * variables to hold them because the AMD64 stores 64 bit values in + * memory MUCH faster than it stores any smaller values. + * + * Rather than passing the context structure to shaCompress, we pass + * this combined array of H and W values. We do not pass the address + * of the first element of this array, but rather pass the address of an + * element in the middle of the array, element X. Presently X[0] is H[11]. + * So we pass the address of H[11] as the address of array X to shaCompress. + * Then shaCompress accesses the members of the array using positive AND + * negative indexes. + * + * Pictorially: (each element is 8 bytes) + * H | H0 H1 H2 H3 H4 W0 W1 W2 W3 W4 W5 W6 W7 W8 W9 Wa Wb Wc Wd We Wf | + * X |-11-10 -9 -8 -7 -6 -5 -4 -3 -2 -1 X0 X1 X2 X3 X4 X5 X6 X7 X8 X9 | + * + * The byte offset from X[0] to any member of H and W is always + * representable in a signed 8-bit value, which will be encoded + * as a single byte offset in the X86-64 instruction set. + * If we didn't pass the address of H[11], and instead passed the + * address of H[0], the offsets to elements H[16] and above would be + * greater than 127, not representable in a signed 8-bit value, and the + * x86-64 instruction set would encode every such offset as a 32-bit + * signed number in each instruction that accessed element H[16] or + * higher. This results in much bigger and slower code. + */ +#define H2X 11 /* X[0] is H[11], and H[0] is X[-11] */ +#define W2X 6 /* X[0] is W[6], and W[0] is X[-6] */ + +/* + * SHA: Add data to context. + */ +void +SHA1Sum::update(const void* aData, uint32_t aLen) +{ + MOZ_ASSERT(!mDone, "SHA1Sum can only be used to compute a single hash."); + + const uint8_t* data = static_cast<const uint8_t*>(aData); + + if (aLen == 0) { + return; + } + + /* Accumulate the byte count. */ + unsigned int lenB = static_cast<unsigned int>(mSize) & 63U; + + mSize += aLen; + + /* Read the data into W and process blocks as they get full. */ + unsigned int togo; + if (lenB > 0) { + togo = 64U - lenB; + if (aLen < togo) { + togo = aLen; + } + memcpy(mU.mB + lenB, data, togo); + aLen -= togo; + data += togo; + lenB = (lenB + togo) & 63U; + if (!lenB) { + shaCompress(&mH[H2X], mU.mW); + } + } + + while (aLen >= 64U) { + aLen -= 64U; + shaCompress(&mH[H2X], reinterpret_cast<const uint32_t*>(data)); + data += 64U; + } + + if (aLen > 0) { + memcpy(mU.mB, data, aLen); + } +} + + +/* + * SHA: Generate hash value + */ +void +SHA1Sum::finish(SHA1Sum::Hash& aHashOut) +{ + MOZ_ASSERT(!mDone, "SHA1Sum can only be used to compute a single hash."); + + uint64_t size = mSize; + uint32_t lenB = uint32_t(size) & 63; + + static const uint8_t bulk_pad[64] = + { 0x80,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, + 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 }; + + /* Pad with a binary 1 (e.g. 0x80), then zeroes, then length in bits. */ + update(bulk_pad, (((55 + 64) - lenB) & 63) + 1); + MOZ_ASSERT((uint32_t(mSize) & 63) == 56); + + /* Convert size from bytes to bits. */ + size <<= 3; + mU.mW[14] = NativeEndian::swapToBigEndian(uint32_t(size >> 32)); + mU.mW[15] = NativeEndian::swapToBigEndian(uint32_t(size)); + shaCompress(&mH[H2X], mU.mW); + + /* Output hash. */ + mU.mW[0] = NativeEndian::swapToBigEndian(mH[0]); + mU.mW[1] = NativeEndian::swapToBigEndian(mH[1]); + mU.mW[2] = NativeEndian::swapToBigEndian(mH[2]); + mU.mW[3] = NativeEndian::swapToBigEndian(mH[3]); + mU.mW[4] = NativeEndian::swapToBigEndian(mH[4]); + memcpy(aHashOut, mU.mW, 20); + mDone = true; +} + +/* + * SHA: Compression function, unrolled. + * + * Some operations in shaCompress are done as 5 groups of 16 operations. + * Others are done as 4 groups of 20 operations. + * The code below shows that structure. + * + * The functions that compute the new values of the 5 state variables + * A-E are done in 4 groups of 20 operations (or you may also think + * of them as being done in 16 groups of 5 operations). They are + * done by the SHA_RNDx macros below, in the right column. + * + * The functions that set the 16 values of the W array are done in + * 5 groups of 16 operations. The first group is done by the + * LOAD macros below, the latter 4 groups are done by SHA_MIX below, + * in the left column. + * + * gcc's optimizer observes that each member of the W array is assigned + * a value 5 times in this code. It reduces the number of store + * operations done to the W array in the context (that is, in the X array) + * by creating a W array on the stack, and storing the W values there for + * the first 4 groups of operations on W, and storing the values in the + * context's W array only in the fifth group. This is undesirable. + * It is MUCH bigger code than simply using the context's W array, because + * all the offsets to the W array in the stack are 32-bit signed offsets, + * and it is no faster than storing the values in the context's W array. + * + * The original code for sha_fast.c prevented this creation of a separate + * W array in the stack by creating a W array of 80 members, each of + * whose elements is assigned only once. It also separated the computations + * of the W array values and the computations of the values for the 5 + * state variables into two separate passes, W's, then A-E's so that the + * second pass could be done all in registers (except for accessing the W + * array) on machines with fewer registers. The method is suboptimal + * for machines with enough registers to do it all in one pass, and it + * necessitates using many instructions with 32-bit offsets. + * + * This code eliminates the separate W array on the stack by a completely + * different means: by declaring the X array volatile. This prevents + * the optimizer from trying to reduce the use of the X array by the + * creation of a MORE expensive W array on the stack. The result is + * that all instructions use signed 8-bit offsets and not 32-bit offsets. + * + * The combination of this code and the -O3 optimizer flag on GCC 3.4.3 + * results in code that is 3 times faster than the previous NSS sha_fast + * code on AMD64. + */ +static void +shaCompress(volatile unsigned* aX, const uint32_t* aBuf) +{ + unsigned A, B, C, D, E; + +#define XH(n) aX[n - H2X] +#define XW(n) aX[n - W2X] + +#define K0 0x5a827999L +#define K1 0x6ed9eba1L +#define K2 0x8f1bbcdcL +#define K3 0xca62c1d6L + +#define SHA_RND1(a, b, c, d, e, n) \ + a = SHA_ROTL(b, 5) + SHA_F1(c, d, e) + a + XW(n) + K0; c = SHA_ROTL(c, 30) +#define SHA_RND2(a, b, c, d, e, n) \ + a = SHA_ROTL(b, 5) + SHA_F2(c, d, e) + a + XW(n) + K1; c = SHA_ROTL(c, 30) +#define SHA_RND3(a, b, c, d, e, n) \ + a = SHA_ROTL(b, 5) + SHA_F3(c, d, e) + a + XW(n) + K2; c = SHA_ROTL(c, 30) +#define SHA_RND4(a, b, c, d, e, n) \ + a = SHA_ROTL(b ,5) + SHA_F4(c, d, e) + a + XW(n) + K3; c = SHA_ROTL(c, 30) + +#define LOAD(n) XW(n) = NativeEndian::swapToBigEndian(aBuf[n]) + + A = XH(0); + B = XH(1); + C = XH(2); + D = XH(3); + E = XH(4); + + LOAD(0); SHA_RND1(E,A,B,C,D, 0); + LOAD(1); SHA_RND1(D,E,A,B,C, 1); + LOAD(2); SHA_RND1(C,D,E,A,B, 2); + LOAD(3); SHA_RND1(B,C,D,E,A, 3); + LOAD(4); SHA_RND1(A,B,C,D,E, 4); + LOAD(5); SHA_RND1(E,A,B,C,D, 5); + LOAD(6); SHA_RND1(D,E,A,B,C, 6); + LOAD(7); SHA_RND1(C,D,E,A,B, 7); + LOAD(8); SHA_RND1(B,C,D,E,A, 8); + LOAD(9); SHA_RND1(A,B,C,D,E, 9); + LOAD(10); SHA_RND1(E,A,B,C,D,10); + LOAD(11); SHA_RND1(D,E,A,B,C,11); + LOAD(12); SHA_RND1(C,D,E,A,B,12); + LOAD(13); SHA_RND1(B,C,D,E,A,13); + LOAD(14); SHA_RND1(A,B,C,D,E,14); + LOAD(15); SHA_RND1(E,A,B,C,D,15); + + SHA_MIX( 0, 13, 8, 2); SHA_RND1(D,E,A,B,C, 0); + SHA_MIX( 1, 14, 9, 3); SHA_RND1(C,D,E,A,B, 1); + SHA_MIX( 2, 15, 10, 4); SHA_RND1(B,C,D,E,A, 2); + SHA_MIX( 3, 0, 11, 5); SHA_RND1(A,B,C,D,E, 3); + + SHA_MIX( 4, 1, 12, 6); SHA_RND2(E,A,B,C,D, 4); + SHA_MIX( 5, 2, 13, 7); SHA_RND2(D,E,A,B,C, 5); + SHA_MIX( 6, 3, 14, 8); SHA_RND2(C,D,E,A,B, 6); + SHA_MIX( 7, 4, 15, 9); SHA_RND2(B,C,D,E,A, 7); + SHA_MIX( 8, 5, 0, 10); SHA_RND2(A,B,C,D,E, 8); + SHA_MIX( 9, 6, 1, 11); SHA_RND2(E,A,B,C,D, 9); + SHA_MIX(10, 7, 2, 12); SHA_RND2(D,E,A,B,C,10); + SHA_MIX(11, 8, 3, 13); SHA_RND2(C,D,E,A,B,11); + SHA_MIX(12, 9, 4, 14); SHA_RND2(B,C,D,E,A,12); + SHA_MIX(13, 10, 5, 15); SHA_RND2(A,B,C,D,E,13); + SHA_MIX(14, 11, 6, 0); SHA_RND2(E,A,B,C,D,14); + SHA_MIX(15, 12, 7, 1); SHA_RND2(D,E,A,B,C,15); + + SHA_MIX( 0, 13, 8, 2); SHA_RND2(C,D,E,A,B, 0); + SHA_MIX( 1, 14, 9, 3); SHA_RND2(B,C,D,E,A, 1); + SHA_MIX( 2, 15, 10, 4); SHA_RND2(A,B,C,D,E, 2); + SHA_MIX( 3, 0, 11, 5); SHA_RND2(E,A,B,C,D, 3); + SHA_MIX( 4, 1, 12, 6); SHA_RND2(D,E,A,B,C, 4); + SHA_MIX( 5, 2, 13, 7); SHA_RND2(C,D,E,A,B, 5); + SHA_MIX( 6, 3, 14, 8); SHA_RND2(B,C,D,E,A, 6); + SHA_MIX( 7, 4, 15, 9); SHA_RND2(A,B,C,D,E, 7); + + SHA_MIX( 8, 5, 0, 10); SHA_RND3(E,A,B,C,D, 8); + SHA_MIX( 9, 6, 1, 11); SHA_RND3(D,E,A,B,C, 9); + SHA_MIX(10, 7, 2, 12); SHA_RND3(C,D,E,A,B,10); + SHA_MIX(11, 8, 3, 13); SHA_RND3(B,C,D,E,A,11); + SHA_MIX(12, 9, 4, 14); SHA_RND3(A,B,C,D,E,12); + SHA_MIX(13, 10, 5, 15); SHA_RND3(E,A,B,C,D,13); + SHA_MIX(14, 11, 6, 0); SHA_RND3(D,E,A,B,C,14); + SHA_MIX(15, 12, 7, 1); SHA_RND3(C,D,E,A,B,15); + + SHA_MIX( 0, 13, 8, 2); SHA_RND3(B,C,D,E,A, 0); + SHA_MIX( 1, 14, 9, 3); SHA_RND3(A,B,C,D,E, 1); + SHA_MIX( 2, 15, 10, 4); SHA_RND3(E,A,B,C,D, 2); + SHA_MIX( 3, 0, 11, 5); SHA_RND3(D,E,A,B,C, 3); + SHA_MIX( 4, 1, 12, 6); SHA_RND3(C,D,E,A,B, 4); + SHA_MIX( 5, 2, 13, 7); SHA_RND3(B,C,D,E,A, 5); + SHA_MIX( 6, 3, 14, 8); SHA_RND3(A,B,C,D,E, 6); + SHA_MIX( 7, 4, 15, 9); SHA_RND3(E,A,B,C,D, 7); + SHA_MIX( 8, 5, 0, 10); SHA_RND3(D,E,A,B,C, 8); + SHA_MIX( 9, 6, 1, 11); SHA_RND3(C,D,E,A,B, 9); + SHA_MIX(10, 7, 2, 12); SHA_RND3(B,C,D,E,A,10); + SHA_MIX(11, 8, 3, 13); SHA_RND3(A,B,C,D,E,11); + + SHA_MIX(12, 9, 4, 14); SHA_RND4(E,A,B,C,D,12); + SHA_MIX(13, 10, 5, 15); SHA_RND4(D,E,A,B,C,13); + SHA_MIX(14, 11, 6, 0); SHA_RND4(C,D,E,A,B,14); + SHA_MIX(15, 12, 7, 1); SHA_RND4(B,C,D,E,A,15); + + SHA_MIX( 0, 13, 8, 2); SHA_RND4(A,B,C,D,E, 0); + SHA_MIX( 1, 14, 9, 3); SHA_RND4(E,A,B,C,D, 1); + SHA_MIX( 2, 15, 10, 4); SHA_RND4(D,E,A,B,C, 2); + SHA_MIX( 3, 0, 11, 5); SHA_RND4(C,D,E,A,B, 3); + SHA_MIX( 4, 1, 12, 6); SHA_RND4(B,C,D,E,A, 4); + SHA_MIX( 5, 2, 13, 7); SHA_RND4(A,B,C,D,E, 5); + SHA_MIX( 6, 3, 14, 8); SHA_RND4(E,A,B,C,D, 6); + SHA_MIX( 7, 4, 15, 9); SHA_RND4(D,E,A,B,C, 7); + SHA_MIX( 8, 5, 0, 10); SHA_RND4(C,D,E,A,B, 8); + SHA_MIX( 9, 6, 1, 11); SHA_RND4(B,C,D,E,A, 9); + SHA_MIX(10, 7, 2, 12); SHA_RND4(A,B,C,D,E,10); + SHA_MIX(11, 8, 3, 13); SHA_RND4(E,A,B,C,D,11); + SHA_MIX(12, 9, 4, 14); SHA_RND4(D,E,A,B,C,12); + SHA_MIX(13, 10, 5, 15); SHA_RND4(C,D,E,A,B,13); + SHA_MIX(14, 11, 6, 0); SHA_RND4(B,C,D,E,A,14); + SHA_MIX(15, 12, 7, 1); SHA_RND4(A,B,C,D,E,15); + + XH(0) += A; + XH(1) += B; + XH(2) += C; + XH(3) += D; + XH(4) += E; +} diff --git a/mfbt/SHA1.h b/mfbt/SHA1.h new file mode 100644 index 000000000..ddccaa67e --- /dev/null +++ b/mfbt/SHA1.h @@ -0,0 +1,63 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Simple class for computing SHA1. */ + +#ifndef mozilla_SHA1_h +#define mozilla_SHA1_h + +#include "mozilla/Types.h" + +#include <stddef.h> +#include <stdint.h> + +namespace mozilla { + +/** + * This class computes the SHA1 hash of a byte sequence, or of the concatenation + * of multiple sequences. For example, computing the SHA1 of two sequences of + * bytes could be done as follows: + * + * void SHA1(const uint8_t* buf1, uint32_t size1, + * const uint8_t* buf2, uint32_t size2, + * SHA1Sum::Hash& hash) + * { + * SHA1Sum s; + * s.update(buf1, size1); + * s.update(buf2, size2); + * s.finish(hash); + * } + * + * The finish method may only be called once and cannot be followed by calls + * to update. + */ +class SHA1Sum +{ + union + { + uint32_t mW[16]; /* input buffer */ + uint8_t mB[64]; + } mU; + uint64_t mSize; /* count of hashed bytes. */ + unsigned mH[22]; /* 5 state variables, 16 tmp values, 1 extra */ + bool mDone; + +public: + MFBT_API SHA1Sum(); + + static const size_t kHashSize = 20; + typedef uint8_t Hash[kHashSize]; + + /* Add len bytes of dataIn to the data sequence being hashed. */ + MFBT_API void update(const void* aData, uint32_t aLength); + + /* Compute the final hash of all data into hashOut. */ + MFBT_API void finish(SHA1Sum::Hash& aHashOut); +}; + +} /* namespace mozilla */ + +#endif /* mozilla_SHA1_h */ diff --git a/mfbt/STYLE b/mfbt/STYLE new file mode 100644 index 000000000..d16be6109 --- /dev/null +++ b/mfbt/STYLE @@ -0,0 +1,11 @@ +MFBT uses standard Mozilla style, with the following exceptions. + +- Some of the files use a lower-case letter at the start of function names. + This is because MFBT used to use a different style, and was later converted + to standard Mozilla style. These functions have not been changed to use an + upper-case letter because it would cause a lot of churn in other parts of the + codebase. However, new files should follow standard Mozilla style and use an + upper-case letter at the start of function names. + +- Imported third-party code (such as decimal/*, double-conversion/*, and lz4*) + remains in its original style. diff --git a/mfbt/Saturate.h b/mfbt/Saturate.h new file mode 100644 index 000000000..b79364d26 --- /dev/null +++ b/mfbt/Saturate.h @@ -0,0 +1,288 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Provides saturation arithmetics for scalar types. */ + +#ifndef mozilla_Saturate_h +#define mozilla_Saturate_h + +#include "mozilla/Attributes.h" +#include "mozilla/Move.h" +#include "mozilla/TypeTraits.h" + +#include <limits> + +namespace mozilla { +namespace detail { + +/** + * |SaturateOp<T>| wraps scalar values for saturation arithmetics. Usage: + * + * uint32_t value = 1; + * + * ++SaturateOp<uint32_t>(value); // value is 2 + * --SaturateOp<uint32_t>(value); // value is 1 + * --SaturateOp<uint32_t>(value); // value is 0 + * --SaturateOp<uint32_t>(value); // value is still 0 + * + * Please add new operators when required. + * + * |SaturateOp<T>| will saturate at the minimum and maximum values of + * type T. If you need other bounds, implement a clamped-type class and + * specialize the type traits accordingly. + */ +template <typename T> +class SaturateOp +{ +public: + explicit SaturateOp(T& aValue) + : mValue(aValue) + { + // We should actually check for |std::is_scalar<T>::value| to be + // true, but this type trait is not available everywhere. Relax + // this assertion if you want to use floating point values as well. + static_assert(IsIntegral<T>::value, + "Integral type required in instantiation"); + } + + // Add and subtract operators + + T operator+(const T& aRhs) const + { + return T(mValue) += aRhs; + } + + T operator-(const T& aRhs) const + { + return T(mValue) -= aRhs; + } + + // Compound operators + + const T& operator+=(const T& aRhs) const + { + const T min = std::numeric_limits<T>::min(); + const T max = std::numeric_limits<T>::max(); + + if (aRhs > static_cast<T>(0)) { + mValue = (max - aRhs) < mValue ? max : mValue + aRhs; + } else { + mValue = (min - aRhs) > mValue ? min : mValue + aRhs; + } + return mValue; + } + + const T& operator-=(const T& aRhs) const + { + const T min = std::numeric_limits<T>::min(); + const T max = std::numeric_limits<T>::max(); + + if (aRhs > static_cast<T>(0)) { + mValue = (min + aRhs) > mValue ? min : mValue - aRhs; + } else { + mValue = (max + aRhs) < mValue ? max : mValue - aRhs; + } + return mValue; + } + + // Increment and decrement operators + + const T& operator++() const // prefix + { + return operator+=(static_cast<T>(1)); + } + + T operator++(int) const // postfix + { + const T value(mValue); + operator++(); + return value; + } + + const T& operator--() const // prefix + { + return operator-=(static_cast<T>(1)); + } + + T operator--(int) const // postfix + { + const T value(mValue); + operator--(); + return value; + } + +private: + SaturateOp(const SaturateOp<T>&) = delete; + SaturateOp(SaturateOp<T>&&) = delete; + SaturateOp& operator=(const SaturateOp<T>&) = delete; + SaturateOp& operator=(SaturateOp<T>&&) = delete; + + T& mValue; +}; + +/** + * |Saturate<T>| is a value type for saturation arithmetics. It's + * build on top of |SaturateOp<T>|. + */ +template <typename T> +class Saturate +{ +public: + Saturate() = default; + MOZ_IMPLICIT Saturate(const Saturate<T>&) = default; + + MOZ_IMPLICIT Saturate(Saturate<T>&& aValue) + { + mValue = Move(aValue.mValue); + } + + explicit Saturate(const T& aValue) + : mValue(aValue) + { } + + const T& value() const + { + return mValue; + } + + // Compare operators + + bool operator==(const Saturate<T>& aRhs) const + { + return mValue == aRhs.mValue; + } + + bool operator!=(const Saturate<T>& aRhs) const + { + return !operator==(aRhs); + } + + bool operator==(const T& aRhs) const + { + return mValue == aRhs; + } + + bool operator!=(const T& aRhs) const + { + return !operator==(aRhs); + } + + // Assignment operators + + Saturate<T>& operator=(const Saturate<T>&) = default; + + Saturate<T>& operator=(Saturate<T>&& aRhs) + { + mValue = Move(aRhs.mValue); + return *this; + } + + // Add and subtract operators + + Saturate<T> operator+(const Saturate<T>& aRhs) const + { + Saturate<T> lhs(mValue); + return lhs += aRhs.mValue; + } + + Saturate<T> operator+(const T& aRhs) const + { + Saturate<T> lhs(mValue); + return lhs += aRhs; + } + + Saturate<T> operator-(const Saturate<T>& aRhs) const + { + Saturate<T> lhs(mValue); + return lhs -= aRhs.mValue; + } + + Saturate<T> operator-(const T& aRhs) const + { + Saturate<T> lhs(mValue); + return lhs -= aRhs; + } + + // Compound operators + + Saturate<T>& operator+=(const Saturate<T>& aRhs) + { + SaturateOp<T>(mValue) += aRhs.mValue; + return *this; + } + + Saturate<T>& operator+=(const T& aRhs) + { + SaturateOp<T>(mValue) += aRhs; + return *this; + } + + Saturate<T>& operator-=(const Saturate<T>& aRhs) + { + SaturateOp<T>(mValue) -= aRhs.mValue; + return *this; + } + + Saturate<T>& operator-=(const T& aRhs) + { + SaturateOp<T>(mValue) -= aRhs; + return *this; + } + + // Increment and decrement operators + + Saturate<T>& operator++() // prefix + { + ++SaturateOp<T>(mValue); + return *this; + } + + Saturate<T> operator++(int) // postfix + { + return Saturate<T>(SaturateOp<T>(mValue)++); + } + + Saturate<T>& operator--() // prefix + { + --SaturateOp<T>(mValue); + return *this; + } + + Saturate<T> operator--(int) // postfix + { + return Saturate<T>(SaturateOp<T>(mValue)--); + } + +private: + T mValue; +}; + +} // namespace detail + +typedef detail::Saturate<int8_t> SaturateInt8; +typedef detail::Saturate<int16_t> SaturateInt16; +typedef detail::Saturate<int32_t> SaturateInt32; +typedef detail::Saturate<uint8_t> SaturateUint8; +typedef detail::Saturate<uint16_t> SaturateUint16; +typedef detail::Saturate<uint32_t> SaturateUint32; + +} // namespace mozilla + +template<typename LhsT, typename RhsT> +bool +operator==(LhsT aLhs, const mozilla::detail::Saturate<RhsT>& aRhs) +{ + return aRhs.operator==(static_cast<RhsT>(aLhs)); +} + +template<typename LhsT, typename RhsT> +bool +operator!=(LhsT aLhs, const mozilla::detail::Saturate<RhsT>& aRhs) +{ + return !(aLhs == aRhs); +} + +#endif // mozilla_Saturate_h diff --git a/mfbt/ScopeExit.h b/mfbt/ScopeExit.h new file mode 100644 index 000000000..7aff82d8a --- /dev/null +++ b/mfbt/ScopeExit.h @@ -0,0 +1,135 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* RAII class for executing arbitrary actions at scope end. */ + +#ifndef mozilla_ScopeExit_h +#define mozilla_ScopeExit_h + +/* + * See http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n4189.pdf for a + * standards-track version of this. + * + * Error handling can be complex when various actions need to be performed that + * need to be undone if an error occurs midway. This can be handled with a + * collection of boolean state variables and gotos, which can get clunky and + * error-prone: + * + * { + * if (!a.setup()) + * goto fail; + * isASetup = true; + * + * if (!b.setup()) + * goto fail; + * isBSetup = true; + * + * ... + * return true; + * + * fail: + * if (isASetup) + * a.teardown(); + * if (isBSetup) + * b.teardown(); + * return false; + * } + * + * ScopeExit is a mechanism to simplify this pattern by keeping an RAII guard + * class that will perform the teardown on destruction, unless released. So the + * above would become: + * + * { + * if (!a.setup()) { + * return false; + * } + * auto guardA = MakeScopeExit([&] { + * a.teardown(); + * }); + * + * if (!b.setup()) { + * return false; + * } + * auto guardB = MakeScopeExit([&] { + * b.teardown(); + * }); + * + * ... + * guardA.release(); + * guardB.release(); + * return true; + * } + * + * This header provides: + * + * - |ScopeExit| - a container for a cleanup call, automically called at the + * end of the scope; + * - |MakeScopeExit| - a convenience function for constructing a |ScopeExit| + * with a given cleanup routine, commonly used with a lambda function. + * + * Note that the RAII classes defined in this header do _not_ perform any form + * of reference-counting or garbage-collection. These classes have exactly two + * behaviors: + * + * - if |release()| has not been called, the cleanup is always performed at + * the end of the scope; + * - if |release()| has been called, nothing will happen at the end of the + * scope. + */ + +#include "mozilla/GuardObjects.h" +#include "mozilla/Move.h" + +namespace mozilla { + +template <typename ExitFunction> +class MOZ_STACK_CLASS ScopeExit { + ExitFunction mExitFunction; + bool mExecuteOnDestruction; + MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER + +public: + explicit ScopeExit(ExitFunction&& cleanup + MOZ_GUARD_OBJECT_NOTIFIER_PARAM) + : mExitFunction(cleanup) + , mExecuteOnDestruction(true) + { + MOZ_GUARD_OBJECT_NOTIFIER_INIT; + } + + ScopeExit(ScopeExit&& rhs) + : mExitFunction(mozilla::Move(rhs.mExitFunction)) + , mExecuteOnDestruction(rhs.mExecuteOnDestruction) + { + rhs.release(); + } + + ~ScopeExit() { + if (mExecuteOnDestruction) { + mExitFunction(); + } + } + + void release() { + mExecuteOnDestruction = false; + } + +private: + explicit ScopeExit(const ScopeExit&) = delete; + ScopeExit& operator=(const ScopeExit&) = delete; + ScopeExit& operator=(ScopeExit&&) = delete; +}; + +template <typename ExitFunction> +ScopeExit<ExitFunction> +MakeScopeExit(ExitFunction&& exitFunction) +{ + return ScopeExit<ExitFunction>(mozilla::Move(exitFunction)); +} + +} /* namespace mozilla */ + +#endif /* mozilla_ScopeExit_h */ diff --git a/mfbt/Scoped.h b/mfbt/Scoped.h new file mode 100644 index 000000000..c935434a2 --- /dev/null +++ b/mfbt/Scoped.h @@ -0,0 +1,255 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* DEPRECATED: Use UniquePtr.h instead. */ + +#ifndef mozilla_Scoped_h +#define mozilla_Scoped_h + +/* + * DEPRECATED: Use UniquePtr.h instead. + * + * Resource Acquisition Is Initialization is a programming idiom used + * to write robust code that is able to deallocate resources properly, + * even in presence of execution errors or exceptions that need to be + * propagated. The Scoped* classes defined via the |SCOPED_TEMPLATE| + * and |MOZ_TYPE_SPECIFIC_SCOPED_POINTER_TEMPLTE| macros perform the + * deallocation of the resource they hold once program execution + * reaches the end of the scope for which they have been defined. + * These macros have been used to automatically close file + * descriptors/file handles when reaching the end of the scope, + * graphics contexts, etc. + * + * The general scenario for RAII classes created by the above macros + * is the following: + * + * ScopedClass foo(create_value()); + * // ... In this scope, |foo| is defined. Use |foo.get()| or |foo.rwget()| + * to access the value. + * // ... In case of |return| or |throw|, |foo| is deallocated automatically. + * // ... If |foo| needs to be returned or stored, use |foo.forget()| + * + * Note that the RAII classes defined in this header do _not_ perform any form + * of reference-counting or garbage-collection. These classes have exactly two + * behaviors: + * + * - if |forget()| has not been called, the resource is always deallocated at + * the end of the scope; + * - if |forget()| has been called, any control on the resource is unbound + * and the resource is not deallocated by the class. + */ + +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" +#include "mozilla/GuardObjects.h" +#include "mozilla/Move.h" + +namespace mozilla { + +/* + * Scoped is a helper to create RAII wrappers + * Type argument |Traits| is expected to have the following structure: + * + * struct Traits + * { + * // Define the type of the value stored in the wrapper + * typedef value_type type; + * // Returns the value corresponding to the uninitialized or freed state + * const static type empty(); + * // Release resources corresponding to the wrapped value + * // This function is responsible for not releasing an |empty| value + * const static void release(type); + * } + */ +template<typename Traits> +class MOZ_NON_TEMPORARY_CLASS Scoped +{ +public: + typedef typename Traits::type Resource; + + explicit Scoped(MOZ_GUARD_OBJECT_NOTIFIER_ONLY_PARAM) + : mValue(Traits::empty()) + { + MOZ_GUARD_OBJECT_NOTIFIER_INIT; + } + + explicit Scoped(const Resource& aValue + MOZ_GUARD_OBJECT_NOTIFIER_PARAM) + : mValue(aValue) + { + MOZ_GUARD_OBJECT_NOTIFIER_INIT; + } + + /* Move constructor. */ + Scoped(Scoped&& aOther + MOZ_GUARD_OBJECT_NOTIFIER_PARAM) + : mValue(Move(aOther.mValue)) + { + MOZ_GUARD_OBJECT_NOTIFIER_INIT; + aOther.mValue = Traits::empty(); + } + + ~Scoped() { Traits::release(mValue); } + + // Constant getter + operator const Resource&() const { return mValue; } + const Resource& operator->() const { return mValue; } + const Resource& get() const { return mValue; } + // Non-constant getter. + Resource& rwget() { return mValue; } + + /* + * Forget the resource. + * + * Once |forget| has been called, the |Scoped| is neutralized, i.e. it will + * have no effect at destruction (unless it is reset to another resource by + * |operator=|). + * + * @return The original resource. + */ + Resource forget() + { + Resource tmp = mValue; + mValue = Traits::empty(); + return tmp; + } + + /* + * Perform immediate clean-up of this |Scoped|. + * + * If this |Scoped| is currently empty, this method has no effect. + */ + void dispose() + { + Traits::release(mValue); + mValue = Traits::empty(); + } + + bool operator==(const Resource& aOther) const { return mValue == aOther; } + + /* + * Replace the resource with another resource. + * + * Calling |operator=| has the side-effect of triggering clean-up. If you do + * not want to trigger clean-up, you should first invoke |forget|. + * + * @return this + */ + Scoped& operator=(const Resource& aOther) { return reset(aOther); } + + Scoped& reset(const Resource& aOther) + { + Traits::release(mValue); + mValue = aOther; + return *this; + } + + /* Move assignment operator. */ + Scoped& operator=(Scoped&& aRhs) + { + MOZ_ASSERT(&aRhs != this, "self-move-assignment not allowed"); + this->~Scoped(); + new(this) Scoped(Move(aRhs)); + return *this; + } + +private: + explicit Scoped(const Scoped& aValue) = delete; + Scoped& operator=(const Scoped& aValue) = delete; + +private: + Resource mValue; + MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER +}; + +/* + * SCOPED_TEMPLATE defines a templated class derived from Scoped + * This allows to implement templates such as ScopedFreePtr. + * + * @param name The name of the class to define. + * @param Traits A struct implementing clean-up. See the implementations + * for more details. + */ +#define SCOPED_TEMPLATE(name, Traits) \ +template<typename Type> \ +struct MOZ_NON_TEMPORARY_CLASS name : public mozilla::Scoped<Traits<Type> > \ +{ \ + typedef mozilla::Scoped<Traits<Type> > Super; \ + typedef typename Super::Resource Resource; \ + name& operator=(Resource aRhs) \ + { \ + Super::operator=(aRhs); \ + return *this; \ + } \ + name& operator=(name&& aRhs) \ + { \ + Super::operator=(Move(aRhs)); \ + return *this; \ + } \ + explicit name(MOZ_GUARD_OBJECT_NOTIFIER_ONLY_PARAM) \ + : Super(MOZ_GUARD_OBJECT_NOTIFIER_ONLY_PARAM_TO_PARENT) \ + {} \ + explicit name(Resource aRhs \ + MOZ_GUARD_OBJECT_NOTIFIER_PARAM) \ + : Super(aRhs \ + MOZ_GUARD_OBJECT_NOTIFIER_PARAM_TO_PARENT) \ + {} \ + name(name&& aRhs \ + MOZ_GUARD_OBJECT_NOTIFIER_PARAM) \ + : Super(Move(aRhs) \ + MOZ_GUARD_OBJECT_NOTIFIER_PARAM_TO_PARENT) \ + {} \ +private: \ + explicit name(name&) = delete; \ + name& operator=(name&) = delete; \ +}; + +/* + * MOZ_TYPE_SPECIFIC_SCOPED_POINTER_TEMPLATE makes it easy to create scoped + * pointers for types with custom deleters; just overload + * TypeSpecificDelete(T*) in the same namespace as T to call the deleter for + * type T. + * + * @param name The name of the class to define. + * @param Type A struct implementing clean-up. See the implementations + * for more details. + * *param Deleter The function that is used to delete/destroy/free a + * non-null value of Type*. + * + * Example: + * + * MOZ_TYPE_SPECIFIC_SCOPED_POINTER_TEMPLATE(ScopedPRFileDesc, PRFileDesc, \ + * PR_Close) + * ... + * { + * ScopedPRFileDesc file(PR_OpenFile(...)); + * ... + * } // file is closed with PR_Close here + */ +#define MOZ_TYPE_SPECIFIC_SCOPED_POINTER_TEMPLATE(name, Type, Deleter) \ +template <> inline void TypeSpecificDelete(Type* aValue) { Deleter(aValue); } \ +typedef ::mozilla::TypeSpecificScopedPointer<Type> name; + +template <typename T> void TypeSpecificDelete(T* aValue); + +template <typename T> +struct TypeSpecificScopedPointerTraits +{ + typedef T* type; + static type empty() { return nullptr; } + static void release(type aValue) + { + if (aValue) { + TypeSpecificDelete(aValue); + } + } +}; + +SCOPED_TEMPLATE(TypeSpecificScopedPointer, TypeSpecificScopedPointerTraits) + +} /* namespace mozilla */ + +#endif /* mozilla_Scoped_h */ diff --git a/mfbt/SegmentedVector.h b/mfbt/SegmentedVector.h new file mode 100644 index 000000000..1bf60e46f --- /dev/null +++ b/mfbt/SegmentedVector.h @@ -0,0 +1,339 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +// A simple segmented vector class. +// +// This class should be used in preference to mozilla::Vector or nsTArray when +// you are simply gathering items in order to later iterate over them. +// +// - In the case where you don't know the final size in advance, using +// SegmentedVector avoids the need to repeatedly allocate increasingly large +// buffers and copy the data into them. +// +// - In the case where you know the final size in advance and so can set the +// capacity appropriately, using SegmentedVector still avoids the need for +// large allocations (which can trigger OOMs). + +#ifndef mozilla_SegmentedVector_h +#define mozilla_SegmentedVector_h + +#include "mozilla/Alignment.h" +#include "mozilla/AllocPolicy.h" +#include "mozilla/Array.h" +#include "mozilla/LinkedList.h" +#include "mozilla/MemoryReporting.h" +#include "mozilla/Move.h" +#include "mozilla/TypeTraits.h" + +#include <new> // for placement new + +namespace mozilla { + +// |IdealSegmentSize| specifies how big each segment will be in bytes (or as +// close as is possible). Use the following guidelines to choose a size. +// +// - It should be a power-of-two, to avoid slop. +// +// - It should not be too small, so that segment allocations are infrequent, +// and so that per-segment bookkeeping overhead is low. Typically each +// segment should be able to hold hundreds of elements, at least. +// +// - It should not be too large, so that OOMs are unlikely when allocating +// segments, and so that not too much space is wasted when the final segment +// is not full. +// +// The ideal size depends on how the SegmentedVector is used and the size of +// |T|, but reasonable sizes include 1024, 4096 (the default), 8192, and 16384. +// +template<typename T, + size_t IdealSegmentSize = 4096, + typename AllocPolicy = MallocAllocPolicy> +class SegmentedVector : private AllocPolicy +{ + template<size_t SegmentCapacity> + struct SegmentImpl + : public mozilla::LinkedListElement<SegmentImpl<SegmentCapacity>> + { + SegmentImpl() : mLength(0) {} + + ~SegmentImpl() + { + for (uint32_t i = 0; i < mLength; i++) { + (*this)[i].~T(); + } + } + + uint32_t Length() const { return mLength; } + + T* Elems() { return reinterpret_cast<T*>(&mStorage.mBuf); } + + T& operator[](size_t aIndex) + { + MOZ_ASSERT(aIndex < mLength); + return Elems()[aIndex]; + } + + const T& operator[](size_t aIndex) const + { + MOZ_ASSERT(aIndex < mLength); + return Elems()[aIndex]; + } + + template<typename U> + void Append(U&& aU) + { + MOZ_ASSERT(mLength < SegmentCapacity); + // Pre-increment mLength so that the bounds-check in operator[] passes. + mLength++; + T* elem = &(*this)[mLength - 1]; + new (elem) T(mozilla::Forward<U>(aU)); + } + + void PopLast() + { + MOZ_ASSERT(mLength > 0); + (*this)[mLength - 1].~T(); + mLength--; + } + + uint32_t mLength; + + // The union ensures that the elements are appropriately aligned. + union Storage + { + char mBuf[sizeof(T) * SegmentCapacity]; + mozilla::AlignedElem<MOZ_ALIGNOF(T)> mAlign; + } mStorage; + + static_assert(MOZ_ALIGNOF(T) == MOZ_ALIGNOF(Storage), + "SegmentedVector provides incorrect alignment"); + }; + + // See how many we elements we can fit in a segment of IdealSegmentSize. If + // IdealSegmentSize is too small, it'll be just one. The +1 is because + // kSingleElementSegmentSize already accounts for one element. + static const size_t kSingleElementSegmentSize = sizeof(SegmentImpl<1>); + static const size_t kSegmentCapacity = + kSingleElementSegmentSize <= IdealSegmentSize + ? (IdealSegmentSize - kSingleElementSegmentSize) / sizeof(T) + 1 + : 1; + + typedef SegmentImpl<kSegmentCapacity> Segment; + +public: + // The |aIdealSegmentSize| is only for sanity checking. If it's specified, we + // check that the actual segment size is as close as possible to it. This + // serves as a sanity check for SegmentedVectorCapacity's capacity + // computation. + explicit SegmentedVector(size_t aIdealSegmentSize = 0) + { + // The difference between the actual segment size and the ideal segment + // size should be less than the size of a single element... unless the + // ideal size was too small, in which case the capacity should be one. + MOZ_ASSERT_IF( + aIdealSegmentSize != 0, + (sizeof(Segment) > aIdealSegmentSize && kSegmentCapacity == 1) || + aIdealSegmentSize - sizeof(Segment) < sizeof(T)); + } + + ~SegmentedVector() { Clear(); } + + bool IsEmpty() const { return !mSegments.getFirst(); } + + // Note that this is O(n) rather than O(1), but the constant factor is very + // small because it only has to do one addition per segment. + size_t Length() const + { + size_t n = 0; + for (auto segment = mSegments.getFirst(); + segment; + segment = segment->getNext()) { + n += segment->Length(); + } + return n; + } + + // Returns false if the allocation failed. (If you are using an infallible + // allocation policy, use InfallibleAppend() instead.) + template<typename U> + MOZ_MUST_USE bool Append(U&& aU) + { + Segment* last = mSegments.getLast(); + if (!last || last->Length() == kSegmentCapacity) { + last = this->template pod_malloc<Segment>(1); + if (!last) { + return false; + } + new (last) Segment(); + mSegments.insertBack(last); + } + last->Append(mozilla::Forward<U>(aU)); + return true; + } + + // You should probably only use this instead of Append() if you are using an + // infallible allocation policy. It will crash if the allocation fails. + template<typename U> + void InfallibleAppend(U&& aU) + { + bool ok = Append(mozilla::Forward<U>(aU)); + MOZ_RELEASE_ASSERT(ok); + } + + void Clear() + { + Segment* segment; + while ((segment = mSegments.popFirst())) { + segment->~Segment(); + this->free_(segment); + } + } + + T& GetLast() + { + MOZ_ASSERT(!IsEmpty()); + Segment* last = mSegments.getLast(); + return (*last)[last->Length() - 1]; + } + + const T& GetLast() const + { + MOZ_ASSERT(!IsEmpty()); + Segment* last = mSegments.getLast(); + return (*last)[last->Length() - 1]; + } + + void PopLast() + { + MOZ_ASSERT(!IsEmpty()); + Segment* last = mSegments.getLast(); + last->PopLast(); + if (!last->Length()) { + mSegments.popLast(); + last->~Segment(); + this->free_(last); + } + } + + // Equivalent to calling |PopLast| |aNumElements| times, but potentially + // more efficient. + void PopLastN(uint32_t aNumElements) + { + MOZ_ASSERT(aNumElements <= Length()); + + Segment* last; + + // Pop full segments for as long as we can. Note that this loop + // cleanly handles the case when the initial last segment is not + // full and we are popping more elements than said segment contains. + do { + last = mSegments.getLast(); + + // The list is empty. We're all done. + if (!last) { + return; + } + + // Check to see if the list contains too many elements. Handle + // that in the epilogue. + uint32_t segmentLen = last->Length(); + if (segmentLen > aNumElements) { + break; + } + + // Destroying the segment destroys all elements contained therein. + mSegments.popLast(); + last->~Segment(); + this->free_(last); + + MOZ_ASSERT(aNumElements >= segmentLen); + aNumElements -= segmentLen; + if (aNumElements == 0) { + return; + } + } while (true); + + // Handle the case where the last segment contains more elements + // than we want to pop. + MOZ_ASSERT(last); + MOZ_ASSERT(last == mSegments.getLast()); + MOZ_ASSERT(aNumElements != 0); + MOZ_ASSERT(aNumElements < last->Length()); + for (uint32_t i = 0; i < aNumElements; ++i) { + last->PopLast(); + } + MOZ_ASSERT(last->Length() != 0); + } + + // Use this class to iterate over a SegmentedVector, like so: + // + // for (auto iter = v.Iter(); !iter.Done(); iter.Next()) { + // MyElem& elem = iter.Get(); + // f(elem); + // } + // + class IterImpl + { + friend class SegmentedVector; + + Segment* mSegment; + size_t mIndex; + + explicit IterImpl(SegmentedVector* aVector) + : mSegment(aVector->mSegments.getFirst()) + , mIndex(0) + {} + + public: + bool Done() const { return !mSegment; } + + T& Get() + { + MOZ_ASSERT(!Done()); + return (*mSegment)[mIndex]; + } + + const T& Get() const + { + MOZ_ASSERT(!Done()); + return (*mSegment)[mIndex]; + } + + void Next() + { + MOZ_ASSERT(!Done()); + mIndex++; + if (mIndex == mSegment->Length()) { + mSegment = mSegment->getNext(); + mIndex = 0; + } + } + }; + + IterImpl Iter() { return IterImpl(this); } + + // Measure the memory consumption of the vector excluding |this|. Note that + // it only measures the vector itself. If the vector elements contain + // pointers to other memory blocks, those blocks must be measured separately + // during a subsequent iteration over the vector. + size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const + { + return mSegments.sizeOfExcludingThis(aMallocSizeOf); + } + + // Like sizeOfExcludingThis(), but measures |this| as well. + size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const + { + return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf); + } + +private: + mozilla::LinkedList<Segment> mSegments; +}; + +} // namespace mozilla + +#endif /* mozilla_SegmentedVector_h */ diff --git a/mfbt/SizePrintfMacros.h b/mfbt/SizePrintfMacros.h new file mode 100644 index 000000000..ec55c62c5 --- /dev/null +++ b/mfbt/SizePrintfMacros.h @@ -0,0 +1,33 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Implements (nonstandard) PRI{ouxX}SIZE format macros for size_t types. */ + +#ifndef mozilla_SizePrintfMacros_h_ +#define mozilla_SizePrintfMacros_h_ + +/* + * MSVC's libc does not support C99's %z format length modifier for size_t + * types. Instead, we use Microsoft's nonstandard %I modifier for size_t, which + * is unsigned __int32 on 32-bit platforms and unsigned __int64 on 64-bit + * platforms: + * + * http://msdn.microsoft.com/en-us/library/tcxf1dw6.aspx + */ + +#if defined(XP_WIN) +# define PRIoSIZE "Io" +# define PRIuSIZE "Iu" +# define PRIxSIZE "Ix" +# define PRIXSIZE "IX" +#else +# define PRIoSIZE "zo" +# define PRIuSIZE "zu" +# define PRIxSIZE "zx" +# define PRIXSIZE "zX" +#endif + +#endif /* mozilla_SizePrintfMacros_h_ */ diff --git a/mfbt/SplayTree.h b/mfbt/SplayTree.h new file mode 100644 index 000000000..2b3b838bf --- /dev/null +++ b/mfbt/SplayTree.h @@ -0,0 +1,330 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/** + * A sorted tree with optimal access times, where recently-accessed elements + * are faster to access again. + */ + +#ifndef mozilla_SplayTree_h +#define mozilla_SplayTree_h + +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" + +namespace mozilla { + +template<class T, class C> +class SplayTree; + +template<typename T> +class SplayTreeNode +{ +public: + template<class A, class B> + friend class SplayTree; + + SplayTreeNode() + : mLeft(nullptr) + , mRight(nullptr) + , mParent(nullptr) + {} + +private: + T* mLeft; + T* mRight; + T* mParent; +}; + + +/** + * Class which represents a splay tree. + * Splay trees are balanced binary search trees for which search, insert and + * remove are all amortized O(log n), but where accessing a node makes it + * faster to access that node in the future. + * + * T indicates the type of tree elements, Comparator must have a static + * compare(const T&, const T&) method ordering the elements. The compare + * method must be free from side effects. + */ +template<typename T, class Comparator> +class SplayTree +{ + T* mRoot; + +public: + constexpr SplayTree() + : mRoot(nullptr) + {} + + bool empty() const + { + return !mRoot; + } + + T* find(const T& aValue) + { + if (empty()) { + return nullptr; + } + + T* last = lookup(aValue); + splay(last); + return Comparator::compare(aValue, *last) == 0 ? last : nullptr; + } + + void insert(T* aValue) + { + MOZ_ASSERT(!find(*aValue), "Duplicate elements are not allowed."); + + if (!mRoot) { + mRoot = aValue; + return; + } + T* last = lookup(*aValue); + int cmp = Comparator::compare(*aValue, *last); + + finishInsertion(last, cmp, aValue); + return; + } + + T* findOrInsert(const T& aValue); + + T* remove(const T& aValue) + { + T* last = lookup(aValue); + MOZ_ASSERT(last, "This tree must contain the element being removed."); + MOZ_ASSERT(Comparator::compare(aValue, *last) == 0); + + // Splay the tree so that the item to remove is the root. + splay(last); + MOZ_ASSERT(last == mRoot); + + // Find another node which can be swapped in for the root: either the + // rightmost child of the root's left, or the leftmost child of the + // root's right. + T* swap; + T* swapChild; + if (mRoot->mLeft) { + swap = mRoot->mLeft; + while (swap->mRight) { + swap = swap->mRight; + } + swapChild = swap->mLeft; + } else if (mRoot->mRight) { + swap = mRoot->mRight; + while (swap->mLeft) { + swap = swap->mLeft; + } + swapChild = swap->mRight; + } else { + T* result = mRoot; + mRoot = nullptr; + return result; + } + + // The selected node has at most one child, in swapChild. Detach it + // from the subtree by replacing it with that child. + if (swap == swap->mParent->mLeft) { + swap->mParent->mLeft = swapChild; + } else { + swap->mParent->mRight = swapChild; + } + if (swapChild) { + swapChild->mParent = swap->mParent; + } + + // Make the selected node the new root. + mRoot = swap; + mRoot->mParent = nullptr; + mRoot->mLeft = last->mLeft; + mRoot->mRight = last->mRight; + if (mRoot->mLeft) { + mRoot->mLeft->mParent = mRoot; + } + if (mRoot->mRight) { + mRoot->mRight->mParent = mRoot; + } + + return last; + } + + T* removeMin() + { + MOZ_ASSERT(mRoot, "No min to remove!"); + + T* min = mRoot; + while (min->mLeft) { + min = min->mLeft; + } + return remove(*min); + } + + // For testing purposes only. + void checkCoherency() + { + checkCoherency(mRoot, nullptr); + } + +private: + /** + * Returns the node in this comparing equal to |aValue|, or a node just + * greater or just less than |aValue| if there is no such node. + */ + T* lookup(const T& aValue) + { + MOZ_ASSERT(!empty()); + + T* node = mRoot; + T* parent; + do { + parent = node; + int c = Comparator::compare(aValue, *node); + if (c == 0) { + return node; + } else if (c < 0) { + node = node->mLeft; + } else { + node = node->mRight; + } + } while (node); + return parent; + } + + void finishInsertion(T* aLast, int32_t aCmp, T* aNew) + { + MOZ_ASSERT(aCmp, "Nodes shouldn't be equal!"); + + T** parentPointer = (aCmp < 0) ? &aLast->mLeft : &aLast->mRight; + MOZ_ASSERT(!*parentPointer); + *parentPointer = aNew; + aNew->mParent = aLast; + + splay(aNew); + } + + /** + * Rotate the tree until |node| is at the root of the tree. Performing + * the rotations in this fashion preserves the amortized balancing of + * the tree. + */ + void splay(T* aNode) + { + MOZ_ASSERT(aNode); + + while (aNode != mRoot) { + T* parent = aNode->mParent; + if (parent == mRoot) { + // Zig rotation. + rotate(aNode); + MOZ_ASSERT(aNode == mRoot); + return; + } + T* grandparent = parent->mParent; + if ((parent->mLeft == aNode) == (grandparent->mLeft == parent)) { + // Zig-zig rotation. + rotate(parent); + rotate(aNode); + } else { + // Zig-zag rotation. + rotate(aNode); + rotate(aNode); + } + } + } + + void rotate(T* aNode) + { + // Rearrange nodes so that aNode becomes the parent of its current + // parent, while preserving the sortedness of the tree. + T* parent = aNode->mParent; + if (parent->mLeft == aNode) { + // x y + // y c ==> a x + // a b b c + parent->mLeft = aNode->mRight; + if (aNode->mRight) { + aNode->mRight->mParent = parent; + } + aNode->mRight = parent; + } else { + MOZ_ASSERT(parent->mRight == aNode); + // x y + // a y ==> x c + // b c a b + parent->mRight = aNode->mLeft; + if (aNode->mLeft) { + aNode->mLeft->mParent = parent; + } + aNode->mLeft = parent; + } + aNode->mParent = parent->mParent; + parent->mParent = aNode; + if (T* grandparent = aNode->mParent) { + if (grandparent->mLeft == parent) { + grandparent->mLeft = aNode; + } else { + grandparent->mRight = aNode; + } + } else { + mRoot = aNode; + } + } + + T* checkCoherency(T* aNode, T* aMinimum) + { + if (mRoot) { + MOZ_RELEASE_ASSERT(!mRoot->mParent); + } + if (!aNode) { + MOZ_RELEASE_ASSERT(!mRoot); + return nullptr; + } + if (!aNode->mParent) { + MOZ_RELEASE_ASSERT(aNode == mRoot); + } + if (aMinimum) { + MOZ_RELEASE_ASSERT(Comparator::compare(*aMinimum, *aNode) < 0); + } + if (aNode->mLeft) { + MOZ_RELEASE_ASSERT(aNode->mLeft->mParent == aNode); + T* leftMaximum = checkCoherency(aNode->mLeft, aMinimum); + MOZ_RELEASE_ASSERT(Comparator::compare(*leftMaximum, *aNode) < 0); + } + if (aNode->mRight) { + MOZ_RELEASE_ASSERT(aNode->mRight->mParent == aNode); + return checkCoherency(aNode->mRight, aNode); + } + return aNode; + } + + SplayTree(const SplayTree&) = delete; + void operator=(const SplayTree&) = delete; +}; + +template<typename T, class Comparator> +T* +SplayTree<T, Comparator>::findOrInsert(const T& aValue) +{ + if (!mRoot) { + mRoot = new T(aValue); + return mRoot; + } + + T* last = lookup(aValue); + int cmp = Comparator::compare(aValue, *last); + if (!cmp) { + return last; + } + + T* t = new T(aValue); + finishInsertion(last, cmp, t); + return t; +} + +} /* namespace mozilla */ + +#endif /* mozilla_SplayTree_h */ diff --git a/mfbt/Sprintf.h b/mfbt/Sprintf.h new file mode 100644 index 000000000..e0be271e5 --- /dev/null +++ b/mfbt/Sprintf.h @@ -0,0 +1,41 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Provides a safer sprintf for printing to fixed-size character arrays. */ + +#ifndef mozilla_Sprintf_h_ +#define mozilla_Sprintf_h_ + +#include <stdio.h> +#include <stdarg.h> + +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" + +#ifdef __cplusplus + +template <size_t N> +int VsprintfLiteral(char (&buffer)[N], const char* format, va_list args) +{ + MOZ_ASSERT(format != buffer); + int result = vsnprintf(buffer, N, format, args); + buffer[N - 1] = '\0'; + return result; +} + +template <size_t N> +MOZ_FORMAT_PRINTF(2, 3) +int SprintfLiteral(char (&buffer)[N], const char* format, ...) +{ + va_list args; + va_start(args, format); + int result = VsprintfLiteral(buffer, format, args); + va_end(args); + return result; +} + +#endif +#endif /* mozilla_Sprintf_h_ */ diff --git a/mfbt/StaticAnalysisFunctions.h b/mfbt/StaticAnalysisFunctions.h new file mode 100644 index 000000000..a06809dc9 --- /dev/null +++ b/mfbt/StaticAnalysisFunctions.h @@ -0,0 +1,49 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef mozilla_StaticAnalysisFunctions_h +#define mozilla_StaticAnalysisFunctions_h + +#ifndef __cplusplus +#ifndef bool +#include <stdbool.h> +#endif +#endif +/* + * Functions that are used as markers in Gecko code for static analysis. Their + * purpose is to have different AST nodes generated during compile time and to + * match them based on different checkers implemented in build/clang-plugin + */ + +#ifdef MOZ_CLANG_PLUGIN + +#ifdef __cplusplus +extern "C" { +#endif + +/* + * MOZ_AssertAssignmentTest - used in MOZ_ASSERT in order to test the possible + * presence of assignment instead of logical comparisons. + * + * Example: + * MOZ_ASSERT(retVal = true); + */ +static MOZ_ALWAYS_INLINE bool MOZ_AssertAssignmentTest(bool exprResult) { + return exprResult; +} + +#ifdef __cplusplus +} +#endif /* __cplusplus */ + +#define MOZ_CHECK_ASSERT_ASSIGNMENT(expr) MOZ_AssertAssignmentTest(!!(expr)) + +#else + +#define MOZ_CHECK_ASSERT_ASSIGNMENT(expr) (!!(expr)) + +#endif /* MOZ_CLANG_PLUGIN */ +#endif /* StaticAnalysisFunctions_h */
\ No newline at end of file diff --git a/mfbt/TaggedAnonymousMemory.cpp b/mfbt/TaggedAnonymousMemory.cpp new file mode 100644 index 000000000..a2ba9ee4b --- /dev/null +++ b/mfbt/TaggedAnonymousMemory.cpp @@ -0,0 +1,105 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifdef ANDROID + +#include "mozilla/TaggedAnonymousMemory.h" + +#include <sys/types.h> +#include <sys/mman.h> +#include <sys/prctl.h> +#include <sys/syscall.h> +#include <unistd.h> + +#include "mozilla/Assertions.h" + +// These constants are copied from <sys/prctl.h>, because the headers +// used for building may not have them even though the running kernel +// supports them. +#ifndef PR_SET_VMA +#define PR_SET_VMA 0x53564d41 +#endif +#ifndef PR_SET_VMA_ANON_NAME +#define PR_SET_VMA_ANON_NAME 0 +#endif + +namespace mozilla { + +// Returns 0 for success and -1 (with errno) for error. +static int +TagAnonymousMemoryAligned(const void* aPtr, size_t aLength, const char* aTag) +{ + return prctl(PR_SET_VMA, + PR_SET_VMA_ANON_NAME, + reinterpret_cast<unsigned long>(aPtr), + aLength, + reinterpret_cast<unsigned long>(aTag)); +} + +// On some architectures, it's possible for the page size to be larger +// than the PAGE_SIZE we were compiled with. This computes the +// equivalent of PAGE_MASK. +static uintptr_t +GetPageMask() +{ + static uintptr_t mask = 0; + + if (mask == 0) { + uintptr_t pageSize = sysconf(_SC_PAGESIZE); + mask = ~(pageSize - 1); + MOZ_ASSERT((pageSize & (pageSize - 1)) == 0, + "Page size must be a power of 2!"); + } + return mask; +} + +} // namespace mozilla + +int +MozTaggedMemoryIsSupported(void) +{ + static int supported = -1; + + if (supported == -1) { + // Tagging an empty range always "succeeds" if the feature is supported, + // regardless of the start pointer. + supported = mozilla::TagAnonymousMemoryAligned(nullptr, 0, nullptr) == 0; + } + return supported; +} + +void +MozTagAnonymousMemory(const void* aPtr, size_t aLength, const char* aTag) +{ + if (MozTaggedMemoryIsSupported()) { + // The kernel will round up the end of the range to the next page + // boundary if it's not aligned (comments indicate this behavior + // is based on that of madvise), but it will reject the request if + // the start is not aligned. We therefore round down the start + // address and adjust the length accordingly. + uintptr_t addr = reinterpret_cast<uintptr_t>(aPtr); + uintptr_t end = addr + aLength; + uintptr_t addrRounded = addr & mozilla::GetPageMask(); + const void* ptrRounded = reinterpret_cast<const void*>(addrRounded); + + mozilla::TagAnonymousMemoryAligned(ptrRounded, end - addrRounded, aTag); + } +} + +void* +MozTaggedAnonymousMmap(void* aAddr, size_t aLength, int aProt, int aFlags, + int aFd, off_t aOffset, const char* aTag) +{ + void* mapped = mmap(aAddr, aLength, aProt, aFlags, aFd, aOffset); + if (MozTaggedMemoryIsSupported() && + (aFlags & MAP_ANONYMOUS) == MAP_ANONYMOUS && + mapped != MAP_FAILED) { + mozilla::TagAnonymousMemoryAligned(mapped, aLength, aTag); + } + return mapped; +} + +#endif // ANDROID diff --git a/mfbt/TaggedAnonymousMemory.h b/mfbt/TaggedAnonymousMemory.h new file mode 100644 index 000000000..d26b06dfb --- /dev/null +++ b/mfbt/TaggedAnonymousMemory.h @@ -0,0 +1,86 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +// Some Linux kernels -- specifically, newer versions of Android and +// some B2G devices -- have a feature for assigning names to ranges of +// anonymous memory (i.e., memory that doesn't have a "name" in the +// form of an underlying mapped file). These names are reported in +// /proc/<pid>/smaps alongside system-level memory usage information +// such as Proportional Set Size (memory usage adjusted for sharing +// between processes), which allows reporting this information at a +// finer granularity than would otherwise be possible (e.g., +// separating malloc() heap from JS heap). +// +// Existing memory can be tagged with MozTagAnonymousMemory(); it will +// tag the range of complete pages containing the given interval, so +// the results may be inexact if the range isn't page-aligned. +// MozTaggedAnonymousMmap() can be used like mmap() with an extra +// parameter, and will tag the returned memory if the mapping was +// successful (and if it was in fact anonymous). +// +// NOTE: The pointer given as the "tag" argument MUST remain valid as +// long as the mapping exists. The referenced string is read when +// /proc/<pid>/smaps or /proc/<pid>/maps is read, not when the tag is +// established, so freeing it or changing its contents will have +// unexpected results. Using a static string is probably best. +// +// Also note that this header can be used by both C and C++ code. + +#ifndef mozilla_TaggedAnonymousMemory_h +#define mozilla_TaggedAnonymousMemory_h + +#ifndef XP_WIN + +#include <sys/types.h> +#include <sys/mman.h> + +#include "mozilla/Types.h" + +#ifdef ANDROID + +#ifdef __cplusplus +extern "C" { +#endif + +MFBT_API void +MozTagAnonymousMemory(const void* aPtr, size_t aLength, const char* aTag); + +MFBT_API void* +MozTaggedAnonymousMmap(void* aAddr, size_t aLength, int aProt, int aFlags, + int aFd, off_t aOffset, const char* aTag); + +MFBT_API int +MozTaggedMemoryIsSupported(void); + +#ifdef __cplusplus +} // extern "C" +#endif + +#else // ANDROID + +static inline void +MozTagAnonymousMemory(const void* aPtr, size_t aLength, const char* aTag) +{ +} + +static inline void* +MozTaggedAnonymousMmap(void* aAddr, size_t aLength, int aProt, int aFlags, + int aFd, off_t aOffset, const char* aTag) +{ + return mmap(aAddr, aLength, aProt, aFlags, aFd, aOffset); +} + +static inline int +MozTaggedMemoryIsSupported(void) +{ + return 0; +} + +#endif // ANDROID + +#endif // !XP_WIN + +#endif // mozilla_TaggedAnonymousMemory_h diff --git a/mfbt/TemplateLib.h b/mfbt/TemplateLib.h new file mode 100644 index 000000000..6286452d8 --- /dev/null +++ b/mfbt/TemplateLib.h @@ -0,0 +1,133 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* + * Reusable template meta-functions on types and compile-time values. Meta- + * functions are placed inside the 'tl' namespace to avoid conflict with non- + * meta functions of the same name (e.g., mozilla::tl::FloorLog2 vs. + * mozilla::FloorLog2). + * + * When constexpr support becomes universal, we should probably use that instead + * of some of these templates, for simplicity. + */ + +#ifndef mozilla_TemplateLib_h +#define mozilla_TemplateLib_h + +#include <limits.h> +#include <stddef.h> + +#include "mozilla/TypeTraits.h" + +namespace mozilla { + +namespace tl { + +/** Compute min/max. */ +template<size_t I, size_t J> +struct Min +{ + static const size_t value = I < J ? I : J; +}; +template<size_t I, size_t J> +struct Max +{ + static const size_t value = I > J ? I : J; +}; + +/** Compute floor(log2(i)). */ +template<size_t I> +struct FloorLog2 +{ + static const size_t value = 1 + FloorLog2<I / 2>::value; +}; +template<> struct FloorLog2<0> { /* Error */ }; +template<> struct FloorLog2<1> { static const size_t value = 0; }; + +/** Compute ceiling(log2(i)). */ +template<size_t I> +struct CeilingLog2 +{ + static const size_t value = FloorLog2<2 * I - 1>::value; +}; + +/** Round up to the nearest power of 2. */ +template<size_t I> +struct RoundUpPow2 +{ + static const size_t value = size_t(1) << CeilingLog2<I>::value; +}; +template<> +struct RoundUpPow2<0> +{ + static const size_t value = 1; +}; + +/** Compute the number of bits in the given unsigned type. */ +template<typename T> +struct BitSize +{ + static const size_t value = sizeof(T) * CHAR_BIT; +}; + +/** + * Produce an N-bit mask, where N <= BitSize<size_t>::value. Handle the + * language-undefined edge case when N = BitSize<size_t>::value. + */ +template<size_t N> +struct NBitMask +{ + // Assert the precondition. On success this evaluates to 0. Otherwise it + // triggers divide-by-zero at compile time: a guaranteed compile error in + // C++11, and usually one in C++98. Add this value to |value| to assure + // its computation. + static const size_t checkPrecondition = + 0 / size_t(N < BitSize<size_t>::value); + static const size_t value = (size_t(1) << N) - 1 + checkPrecondition; +}; +template<> +struct NBitMask<BitSize<size_t>::value> +{ + static const size_t value = size_t(-1); +}; + +/** + * For the unsigned integral type size_t, compute a mask M for N such that + * for all X, !(X & M) implies X * N will not overflow (w.r.t size_t) + */ +template<size_t N> +struct MulOverflowMask +{ + static const size_t value = + ~NBitMask<BitSize<size_t>::value - CeilingLog2<N>::value>::value; +}; +template<> struct MulOverflowMask<0> { /* Error */ }; +template<> struct MulOverflowMask<1> { static const size_t value = 0; }; + +/** + * And<bool...> computes the logical 'and' of its argument booleans. + * + * Examples: + * mozilla::t1::And<true, true>::value is true. + * mozilla::t1::And<true, false>::value is false. + * mozilla::t1::And<>::value is true. + */ + +template<bool...> +struct And; + +template<> +struct And<> : public TrueType { }; + +template<bool C1, bool... Cn> +struct And<C1, Cn...> + : public Conditional<C1, And<Cn...>, FalseType>::Type { }; + +} // namespace tl + +} // namespace mozilla + +#endif /* mozilla_TemplateLib_h */ diff --git a/mfbt/ThreadLocal.h b/mfbt/ThreadLocal.h new file mode 100644 index 000000000..880e67735 --- /dev/null +++ b/mfbt/ThreadLocal.h @@ -0,0 +1,222 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Cross-platform lightweight thread local data wrappers. */ + +#ifndef mozilla_ThreadLocal_h +#define mozilla_ThreadLocal_h + +#if defined(XP_WIN) +// This file will get included in any file that wants to add a profiler mark. +// In order to not bring <windows.h> together we could include windef.h and +// winbase.h which are sufficient to get the prototypes for the Tls* functions. +// # include <windef.h> +// # include <winbase.h> +// Unfortunately, even including these headers causes us to add a bunch of ugly +// stuff to our namespace e.g #define CreateEvent CreateEventW +extern "C" { +__declspec(dllimport) void* __stdcall TlsGetValue(unsigned long); +__declspec(dllimport) int __stdcall TlsSetValue(unsigned long, void*); +__declspec(dllimport) unsigned long __stdcall TlsAlloc(); +} +#else +# include <pthread.h> +# include <signal.h> +#endif + +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" +#include "mozilla/TypeTraits.h" + +namespace mozilla { + +// sig_safe_t denotes an atomic type which can be read or stored in a single +// instruction. This means that data of this type is safe to be manipulated +// from a signal handler, or other similar asynchronous execution contexts. +#if defined(XP_WIN) +typedef unsigned long sig_safe_t; +#else +typedef sig_atomic_t sig_safe_t; +#endif + +namespace detail { + +#if defined(HAVE_THREAD_TLS_KEYWORD) +#define MOZ_HAS_THREAD_LOCAL +#endif + +/* + * Thread Local Storage helpers. + * + * Usage: + * + * Do not directly instantiate this class. Instead, use the + * MOZ_THREAD_LOCAL macro to declare or define instances. The macro + * takes a type name as its argument. + * + * Declare like this: + * extern MOZ_THREAD_LOCAL(int) tlsInt; + * Define like this: + * MOZ_THREAD_LOCAL(int) tlsInt; + * or: + * static MOZ_THREAD_LOCAL(int) tlsInt; + * + * Only static-storage-duration (e.g. global variables, or static class members) + * objects of this class should be instantiated. This class relies on + * zero-initialization, which is implicit for static-storage-duration objects. + * It doesn't have a custom default constructor, to avoid static initializers. + * + * API usage: + * + * // Create a TLS item. + * // + * // Note that init() should be invoked before the first use of set() + * // or get(). It is ok to call it multiple times. This must be + * // called in a way that avoids possible races with other threads. + * MOZ_THREAD_LOCAL(int) tlsKey; + * if (!tlsKey.init()) { + * // deal with the error + * } + * + * // Set the TLS value + * tlsKey.set(123); + * + * // Get the TLS value + * int value = tlsKey.get(); + */ +template<typename T> +class ThreadLocal +{ +#ifndef MOZ_HAS_THREAD_LOCAL +#if defined(XP_WIN) + typedef unsigned long key_t; +#else + typedef pthread_key_t key_t; +#endif + + // Integral types narrower than void* must be extended to avoid + // warnings from valgrind on some platforms. This helper type + // achieves that without penalizing the common case of ThreadLocals + // instantiated using a pointer type. + template<typename S> + struct Helper + { + typedef uintptr_t Type; + }; + + template<typename S> + struct Helper<S *> + { + typedef S *Type; + }; +#endif + + bool initialized() const { +#ifdef MOZ_HAS_THREAD_LOCAL + return true; +#else + return mInited; +#endif + } + +public: + // __thread does not allow non-trivial constructors, but we can + // instead rely on zero-initialization. +#ifndef MOZ_HAS_THREAD_LOCAL + ThreadLocal() + : mKey(0), mInited(false) + {} +#endif + + MOZ_MUST_USE inline bool init(); + + inline T get() const; + + inline void set(const T aValue); + +private: +#ifdef MOZ_HAS_THREAD_LOCAL + T mValue; +#else + key_t mKey; + bool mInited; +#endif +}; + +template<typename T> +inline bool +ThreadLocal<T>::init() +{ + static_assert(mozilla::IsPointer<T>::value || mozilla::IsIntegral<T>::value, + "mozilla::ThreadLocal must be used with a pointer or " + "integral type"); + static_assert(sizeof(T) <= sizeof(void*), + "mozilla::ThreadLocal can't be used for types larger than " + "a pointer"); + +#ifdef MOZ_HAS_THREAD_LOCAL + return true; +#else + if (!initialized()) { +#ifdef XP_WIN + mKey = TlsAlloc(); + mInited = mKey != 0xFFFFFFFFUL; // TLS_OUT_OF_INDEXES +#else + mInited = !pthread_key_create(&mKey, nullptr); +#endif + } + return mInited; +#endif +} + +template<typename T> +inline T +ThreadLocal<T>::get() const +{ +#ifdef MOZ_HAS_THREAD_LOCAL + return mValue; +#else + MOZ_ASSERT(initialized()); + void* h; +#ifdef XP_WIN + h = TlsGetValue(mKey); +#else + h = pthread_getspecific(mKey); +#endif + return static_cast<T>(reinterpret_cast<typename Helper<T>::Type>(h)); +#endif +} + +template<typename T> +inline void +ThreadLocal<T>::set(const T aValue) +{ +#ifdef MOZ_HAS_THREAD_LOCAL + mValue = aValue; +#else + MOZ_ASSERT(initialized()); + void* h = reinterpret_cast<void*>(static_cast<typename Helper<T>::Type>(aValue)); +#ifdef XP_WIN + bool succeeded = TlsSetValue(mKey, h); +#else + bool succeeded = !pthread_setspecific(mKey, h); +#endif + if (!succeeded) { + MOZ_CRASH(); + } +#endif +} + +#ifdef MOZ_HAS_THREAD_LOCAL +#define MOZ_THREAD_LOCAL(TYPE) __thread mozilla::detail::ThreadLocal<TYPE> +#else +#define MOZ_THREAD_LOCAL(TYPE) mozilla::detail::ThreadLocal<TYPE> +#endif + +} // namespace detail +} // namespace mozilla + +#endif /* mozilla_ThreadLocal_h */ diff --git a/mfbt/ToString.h b/mfbt/ToString.h new file mode 100644 index 000000000..f11cad5cb --- /dev/null +++ b/mfbt/ToString.h @@ -0,0 +1,32 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Utilities for converting an object to a string representation. */ + +#ifndef mozilla_ToString_h +#define mozilla_ToString_h + +#include <string> +#include <sstream> + +namespace mozilla { + +/** + * A convenience function for converting an object to a string representation. + * Supports any object which can be streamed to an std::ostream. + */ +template<typename T> +std::string +ToString(const T& aValue) +{ + std::ostringstream stream; + stream << aValue; + return stream.str(); +} + +} // namespace mozilla + +#endif /* mozilla_ToString_h */ diff --git a/mfbt/Tuple.h b/mfbt/Tuple.h new file mode 100644 index 000000000..a7f9bee6c --- /dev/null +++ b/mfbt/Tuple.h @@ -0,0 +1,461 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* A variadic tuple class. */ + +#ifndef mozilla_Tuple_h +#define mozilla_Tuple_h + +#include "mozilla/Move.h" +#include "mozilla/Pair.h" +#include "mozilla/TemplateLib.h" +#include "mozilla/TypeTraits.h" + +#include <stddef.h> +#include <utility> + +namespace mozilla { + +namespace detail { + +/* + * A helper class that allows passing around multiple variadic argument lists + * by grouping them. + */ +template<typename... Ts> +struct Group; + +/* + * CheckConvertibility checks whether each type in a source pack of types + * is convertible to the corresponding type in a target pack of types. + * + * It is intended to be invoked like this: + * CheckConvertibility<Group<SourceTypes...>, Group<TargetTypes...>> + * 'Group' is used to separate types in the two packs (otherwise if we just + * wrote 'CheckConvertibility<SourceTypes..., TargetTypes...', it couldn't + * know where the first pack ends and the second begins). + * + * Note that we need to check explicitly that the two packs are of the same + * size, because attempting to simultaneously expand two parameter packs + * is an error (and it would be a hard error, because it wouldn't be in the + * immediate context of the caller). + */ + +template<typename Source, typename Target, bool SameSize> +struct CheckConvertibilityImpl; + +template<typename Source, typename Target> +struct CheckConvertibilityImpl<Source, Target, false> + : FalseType {}; + +template<typename... SourceTypes, typename... TargetTypes> +struct CheckConvertibilityImpl<Group<SourceTypes...>, Group<TargetTypes...>, true> + : IntegralConstant<bool, tl::And<IsConvertible<SourceTypes, TargetTypes>::value...>::value> { }; + +template<typename Source, typename Target> +struct CheckConvertibility; + +template<typename... SourceTypes, typename... TargetTypes> +struct CheckConvertibility<Group<SourceTypes...>, Group<TargetTypes...>> + : CheckConvertibilityImpl<Group<SourceTypes...>, Group<TargetTypes...>, + sizeof...(SourceTypes) == sizeof...(TargetTypes)> { }; + +/* + * TupleImpl is a helper class used to implement mozilla::Tuple. + * It represents one node in a recursive inheritance hierarchy. + * 'Index' is the 0-based index of the tuple element stored in this node; + * 'Elements...' are the types of the elements stored in this node and its + * base classes. + * + * Example: + * Tuple<int, float, char> inherits from + * TupleImpl<0, int, float, char>, which stores the 'int' and inherits from + * TupleImpl<1, float, char>, which stores the 'float' and inherits from + * TupleImpl<2, char>, which stores the 'char' and inherits from + * TupleImpl<3>, which stores nothing and terminates the recursion. + * + * The purpose of the 'Index' parameter is to allow efficient index-based + * access to a tuple element: given a tuple, and an index 'I' that we wish to + * access, we can cast the tuple to the base which stores the I'th element + * by performing template argument deduction against 'TupleImpl<I, E...>', + * where 'I' is specified explicitly and 'E...' is deduced (this is what the + * non-member 'Get<N>(t)' function does). + * + * This implementation strategy is borrowed from libstdc++'s std::tuple + * implementation. + */ +template<std::size_t Index, typename... Elements> +struct TupleImpl; + +/* + * The base case of the inheritance recursion (and also the implementation + * of an empty tuple). + */ +template<std::size_t Index> +struct TupleImpl<Index> { + bool operator==(const TupleImpl<Index>& aOther) const + { + return true; + } +}; + +/* + * One node of the recursive inheritance hierarchy. It stores the element at + * index 'Index' of a tuple, of type 'HeadT', and inherits from the nodes + * that store the remaining elements, of types 'TailT...'. + */ +template<std::size_t Index, typename HeadT, typename... TailT> +struct TupleImpl<Index, HeadT, TailT...> + : public TupleImpl<Index + 1, TailT...> +{ + typedef TupleImpl<Index + 1, TailT...> Base; + + // Accessors for the head and the tail. + // These are static, because the intended usage is for the caller to, + // given a tuple, obtain the type B of the base class which stores the + // element of interest, and then call B::Head(tuple) to access it. + // (Tail() is mostly for internal use, but is exposed for consistency.) + static HeadT& Head(TupleImpl& aTuple) { return aTuple.mHead; } + static const HeadT& Head(const TupleImpl& aTuple) { return aTuple.mHead; } + static Base& Tail(TupleImpl& aTuple) { return aTuple; } + static const Base& Tail(const TupleImpl& aTuple) { return aTuple; } + + TupleImpl() : Base(), mHead() { } + + // Construct from const references to the elements. + explicit TupleImpl(const HeadT& aHead, const TailT&... aTail) + : Base(aTail...), mHead(aHead) { } + + // Construct from objects that are convertible to the elements. + // This constructor is enabled only when the argument types are actually + // convertible to the element types, otherwise it could become a better + // match for certain invocations than the copy constructor. + template <typename OtherHeadT, typename... OtherTailT, + typename = typename EnableIf< + CheckConvertibility< + Group<OtherHeadT, OtherTailT...>, + Group<HeadT, TailT...>>::value>::Type> + explicit TupleImpl(OtherHeadT&& aHead, OtherTailT&&... aTail) + : Base(Forward<OtherTailT>(aTail)...), mHead(Forward<OtherHeadT>(aHead)) { } + + // Copy and move constructors. + // We'd like to use '= default' to implement these, but MSVC 2013's support + // for '= default' is incomplete and this doesn't work. + TupleImpl(const TupleImpl& aOther) + : Base(Tail(aOther)) + , mHead(Head(aOther)) {} + TupleImpl(TupleImpl&& aOther) + : Base(Move(Tail(aOther))) + , mHead(Forward<HeadT>(Head(aOther))) {} + + // Assign from a tuple whose elements are convertible to the elements + // of this tuple. + template <typename... OtherElements, + typename = typename EnableIf< + sizeof...(OtherElements) == sizeof...(TailT) + 1>::Type> + TupleImpl& operator=(const TupleImpl<Index, OtherElements...>& aOther) + { + typedef TupleImpl<Index, OtherElements...> OtherT; + Head(*this) = OtherT::Head(aOther); + Tail(*this) = OtherT::Tail(aOther); + return *this; + } + template <typename... OtherElements, + typename = typename EnableIf< + sizeof...(OtherElements) == sizeof...(TailT) + 1>::Type> + TupleImpl& operator=(TupleImpl<Index, OtherElements...>&& aOther) + { + typedef TupleImpl<Index, OtherElements...> OtherT; + Head(*this) = Move(OtherT::Head(aOther)); + Tail(*this) = Move(OtherT::Tail(aOther)); + return *this; + } + + // Copy and move assignment operators. + TupleImpl& operator=(const TupleImpl& aOther) + { + Head(*this) = Head(aOther); + Tail(*this) = Tail(aOther); + return *this; + } + TupleImpl& operator=(TupleImpl&& aOther) + { + Head(*this) = Move(Head(aOther)); + Tail(*this) = Move(Tail(aOther)); + return *this; + } + bool operator==(const TupleImpl& aOther) const + { + return Head(*this) == Head(aOther) && Tail(*this) == Tail(aOther); + } +private: + HeadT mHead; // The element stored at this index in the tuple. +}; + +} // namespace detail + +/** + * Tuple is a class that stores zero or more objects, whose types are specified + * as template parameters. It can be thought of as a generalization of Pair, + * (which can be thought of as a 2-tuple). + * + * Tuple allows index-based access to its elements (with the index having to be + * known at compile time) via the non-member function 'Get<N>(tuple)'. + */ +template<typename... Elements> +class Tuple : public detail::TupleImpl<0, Elements...> +{ + typedef detail::TupleImpl<0, Elements...> Impl; +public: + // The constructors and assignment operators here are simple wrappers + // around those in TupleImpl. + + Tuple() : Impl() { } + explicit Tuple(const Elements&... aElements) : Impl(aElements...) { } + // Here, we can't just use 'typename... OtherElements' because MSVC will give + // a warning "C4520: multiple default constructors specified" (even if no one + // actually instantiates the constructor with an empty parameter pack - + // that's probably a bug) and we compile with warnings-as-errors. + template <typename OtherHead, typename... OtherTail, + typename = typename EnableIf< + detail::CheckConvertibility< + detail::Group<OtherHead, OtherTail...>, + detail::Group<Elements...>>::value>::Type> + explicit Tuple(OtherHead&& aHead, OtherTail&&... aTail) + : Impl(Forward<OtherHead>(aHead), Forward<OtherTail>(aTail)...) { } + Tuple(const Tuple& aOther) : Impl(aOther) { } + Tuple(Tuple&& aOther) : Impl(Move(aOther)) { } + + template <typename... OtherElements, + typename = typename EnableIf< + sizeof...(OtherElements) == sizeof...(Elements)>::Type> + Tuple& operator=(const Tuple<OtherElements...>& aOther) + { + static_cast<Impl&>(*this) = aOther; + return *this; + } + template <typename... OtherElements, + typename = typename EnableIf< + sizeof...(OtherElements) == sizeof...(Elements)>::Type> + Tuple& operator=(Tuple<OtherElements...>&& aOther) + { + static_cast<Impl&>(*this) = Move(aOther); + return *this; + } + Tuple& operator=(const Tuple& aOther) + { + static_cast<Impl&>(*this) = aOther; + return *this; + } + Tuple& operator=(Tuple&& aOther) + { + static_cast<Impl&>(*this) = Move(aOther); + return *this; + } + bool operator==(const Tuple& aOther) const + { + return static_cast<const Impl&>(*this) == static_cast<const Impl&>(aOther); + } +}; + +/** + * Specialization of Tuple for two elements. + * This is created to support construction and assignment from a Pair or std::pair. + */ +template <typename A, typename B> +class Tuple<A, B> : public detail::TupleImpl<0, A, B> +{ + typedef detail::TupleImpl<0, A, B> Impl; + +public: + // The constructors and assignment operators here are simple wrappers + // around those in TupleImpl. + + Tuple() : Impl() { } + explicit Tuple(const A& aA, const B& aB) : Impl(aA, aB) { } + template <typename AArg, typename BArg, + typename = typename EnableIf< + detail::CheckConvertibility< + detail::Group<AArg, BArg>, + detail::Group<A, B>>::value>::Type> + explicit Tuple(AArg&& aA, BArg&& aB) + : Impl(Forward<AArg>(aA), Forward<BArg>(aB)) { } + Tuple(const Tuple& aOther) : Impl(aOther) { } + Tuple(Tuple&& aOther) : Impl(Move(aOther)) { } + explicit Tuple(const Pair<A, B>& aOther) + : Impl(aOther.first(), aOther.second()) { } + explicit Tuple(Pair<A, B>&& aOther) : Impl(Forward<A>(aOther.first()), + Forward<B>(aOther.second())) { } + explicit Tuple(const std::pair<A, B>& aOther) + : Impl(aOther.first, aOther.second) { } + explicit Tuple(std::pair<A, B>&& aOther) : Impl(Forward<A>(aOther.first), + Forward<B>(aOther.second)) { } + + template <typename AArg, typename BArg> + Tuple& operator=(const Tuple<AArg, BArg>& aOther) + { + static_cast<Impl&>(*this) = aOther; + return *this; + } + template <typename AArg, typename BArg> + Tuple& operator=(Tuple<AArg, BArg>&& aOther) + { + static_cast<Impl&>(*this) = Move(aOther); + return *this; + } + Tuple& operator=(const Tuple& aOther) + { + static_cast<Impl&>(*this) = aOther; + return *this; + } + Tuple& operator=(Tuple&& aOther) + { + static_cast<Impl&>(*this) = Move(aOther); + return *this; + } + template <typename AArg, typename BArg> + Tuple& operator=(const Pair<AArg, BArg>& aOther) + { + Impl::Head(*this) = aOther.first(); + Impl::Tail(*this).Head(*this) = aOther.second(); + return *this; + } + template <typename AArg, typename BArg> + Tuple& operator=(Pair<AArg, BArg>&& aOther) + { + Impl::Head(*this) = Forward<AArg>(aOther.first()); + Impl::Tail(*this).Head(*this) = Forward<BArg>(aOther.second()); + return *this; + } + template <typename AArg, typename BArg> + Tuple& operator=(const std::pair<AArg, BArg>& aOther) + { + Impl::Head(*this) = aOther.first; + Impl::Tail(*this).Head(*this) = aOther.second; + return *this; + } + template <typename AArg, typename BArg> + Tuple& operator=(std::pair<AArg, BArg>&& aOther) + { + Impl::Head(*this) = Forward<AArg>(aOther.first); + Impl::Tail(*this).Head(*this) = Forward<BArg>(aOther.second); + return *this; + } +}; + +/** + * Specialization of Tuple for zero arguments. + * This is necessary because if the primary template were instantiated with + * an empty parameter pack, the 'Tuple(Elements...)' constructors would + * become illegal overloads of the default constructor. + */ +template <> +class Tuple<> {}; + +namespace detail { + +/* + * Helper functions for implementing Get<N>(tuple). + * These functions take a TupleImpl<Index, Elements...>, with Index being + * explicitly specified, and Elements being deduced. By passing a Tuple + * object as argument, template argument deduction will do its magic and + * cast the tuple to the base class which stores the element at Index. + */ + +// Const reference version. +template<std::size_t Index, typename... Elements> +auto TupleGetHelper(TupleImpl<Index, Elements...>& aTuple) + -> decltype(TupleImpl<Index, Elements...>::Head(aTuple)) +{ + return TupleImpl<Index, Elements...>::Head(aTuple); +} + +// Non-const reference version. +template<std::size_t Index, typename... Elements> +auto TupleGetHelper(const TupleImpl<Index, Elements...>& aTuple) + -> decltype(TupleImpl<Index, Elements...>::Head(aTuple)) +{ + return TupleImpl<Index, Elements...>::Head(aTuple); +} + +} // namespace detail + +/** + * Index-based access to an element of a tuple. + * The syntax is Get<Index>(tuple). The index is zero-based. + * + * Example: + * + * Tuple<int, float, char> t; + * ... + * float f = Get<1>(t); + */ + +// Non-const reference version. +template<std::size_t Index, typename... Elements> +auto Get(Tuple<Elements...>& aTuple) + -> decltype(detail::TupleGetHelper<Index>(aTuple)) +{ + return detail::TupleGetHelper<Index>(aTuple); +} + +// Const reference version. +template<std::size_t Index, typename... Elements> +auto Get(const Tuple<Elements...>& aTuple) + -> decltype(detail::TupleGetHelper<Index>(aTuple)) +{ + return detail::TupleGetHelper<Index>(aTuple); +} + +// Rvalue reference version. +template<std::size_t Index, typename... Elements> +auto Get(Tuple<Elements...>&& aTuple) + -> decltype(Move(mozilla::Get<Index>(aTuple))) +{ + // We need a 'mozilla::' qualification here to avoid + // name lookup only finding the current function. + return Move(mozilla::Get<Index>(aTuple)); +} + +/** + * A convenience function for constructing a tuple out of a sequence of + * values without specifying the type of the tuple. + * The type of the tuple is deduced from the types of its elements. + * + * Example: + * + * auto tuple = MakeTuple(42, 0.5f, 'c'); // has type Tuple<int, float, char> + */ +template<typename... Elements> +inline Tuple<typename Decay<Elements>::Type...> +MakeTuple(Elements&&... aElements) +{ + return Tuple<typename Decay<Elements>::Type...>(Forward<Elements>(aElements)...); +} + +/** + * A convenience function for constructing a tuple of references to a + * sequence of variables. Since assignments to the elements of the tuple + * "go through" to the referenced variables, this can be used to "unpack" + * a tuple into individual variables. + * + * Example: + * + * int i; + * float f; + * char c; + * Tie(i, f, c) = FunctionThatReturnsATuple(); + */ +template<typename... Elements> +inline Tuple<Elements&...> +Tie(Elements&... aVariables) +{ + return Tuple<Elements&...>(aVariables...); +} + +} // namespace mozilla + +#endif /* mozilla_Tuple_h */ diff --git a/mfbt/TypeTraits.h b/mfbt/TypeTraits.h new file mode 100644 index 000000000..084f608ca --- /dev/null +++ b/mfbt/TypeTraits.h @@ -0,0 +1,1262 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Template-based metaprogramming and type-testing facilities. */ + +#ifndef mozilla_TypeTraits_h +#define mozilla_TypeTraits_h + +#include "mozilla/Types.h" + +/* + * These traits are approximate copies of the traits and semantics from C++11's + * <type_traits> header. Don't add traits not in that header! When all + * platforms provide that header, we can convert all users and remove this one. + */ + +#include <wchar.h> + +namespace mozilla { + +/* Forward declarations. */ + +template<typename> struct RemoveCV; +template<typename> struct AddRvalueReference; + +/* 20.2.4 Function template declval [declval] */ + +/** + * DeclVal simplifies the definition of expressions which occur as unevaluated + * operands. It converts T to a reference type, making it possible to use in + * decltype expressions even if T does not have a default constructor, e.g.: + * decltype(DeclVal<TWithNoDefaultConstructor>().foo()) + */ +template<typename T> +typename AddRvalueReference<T>::Type DeclVal(); + +/* 20.9.3 Helper classes [meta.help] */ + +/** + * Helper class used as a base for various type traits, exposed publicly + * because <type_traits> exposes it as well. + */ +template<typename T, T Value> +struct IntegralConstant +{ + static const T value = Value; + typedef T ValueType; + typedef IntegralConstant<T, Value> Type; +}; + +/** Convenient aliases. */ +typedef IntegralConstant<bool, true> TrueType; +typedef IntegralConstant<bool, false> FalseType; + +/* 20.9.4 Unary type traits [meta.unary] */ + +/* 20.9.4.1 Primary type categories [meta.unary.cat] */ + +namespace detail { + +template<typename T> +struct IsVoidHelper : FalseType {}; + +template<> +struct IsVoidHelper<void> : TrueType {}; + +} // namespace detail + +/** + * IsVoid determines whether a type is void. + * + * mozilla::IsVoid<int>::value is false; + * mozilla::IsVoid<void>::value is true; + * mozilla::IsVoid<void*>::value is false; + * mozilla::IsVoid<volatile void>::value is true. + */ +template<typename T> +struct IsVoid : detail::IsVoidHelper<typename RemoveCV<T>::Type> {}; + +namespace detail { + +template <typename T> +struct IsIntegralHelper : FalseType {}; + +template<> struct IsIntegralHelper<char> : TrueType {}; +template<> struct IsIntegralHelper<signed char> : TrueType {}; +template<> struct IsIntegralHelper<unsigned char> : TrueType {}; +template<> struct IsIntegralHelper<short> : TrueType {}; +template<> struct IsIntegralHelper<unsigned short> : TrueType {}; +template<> struct IsIntegralHelper<int> : TrueType {}; +template<> struct IsIntegralHelper<unsigned int> : TrueType {}; +template<> struct IsIntegralHelper<long> : TrueType {}; +template<> struct IsIntegralHelper<unsigned long> : TrueType {}; +template<> struct IsIntegralHelper<long long> : TrueType {}; +template<> struct IsIntegralHelper<unsigned long long> : TrueType {}; +template<> struct IsIntegralHelper<bool> : TrueType {}; +template<> struct IsIntegralHelper<wchar_t> : TrueType {}; +template<> struct IsIntegralHelper<char16_t> : TrueType {}; + +} /* namespace detail */ + +/** + * IsIntegral determines whether a type is an integral type. + * + * mozilla::IsIntegral<int>::value is true; + * mozilla::IsIntegral<unsigned short>::value is true; + * mozilla::IsIntegral<const long>::value is true; + * mozilla::IsIntegral<int*>::value is false; + * mozilla::IsIntegral<double>::value is false; + */ +template<typename T> +struct IsIntegral : detail::IsIntegralHelper<typename RemoveCV<T>::Type> +{}; + +template<typename T, typename U> +struct IsSame; + +namespace detail { + +template<typename T> +struct IsFloatingPointHelper + : IntegralConstant<bool, + IsSame<T, float>::value || + IsSame<T, double>::value || + IsSame<T, long double>::value> +{}; + +} // namespace detail + +/** + * IsFloatingPoint determines whether a type is a floating point type (float, + * double, long double). + * + * mozilla::IsFloatingPoint<int>::value is false; + * mozilla::IsFloatingPoint<const float>::value is true; + * mozilla::IsFloatingPoint<long double>::value is true; + * mozilla::IsFloatingPoint<double*>::value is false. + */ +template<typename T> +struct IsFloatingPoint + : detail::IsFloatingPointHelper<typename RemoveCV<T>::Type> +{}; + +namespace detail { + +template<typename T> +struct IsArrayHelper : FalseType {}; + +template<typename T, decltype(sizeof(1)) N> +struct IsArrayHelper<T[N]> : TrueType {}; + +template<typename T> +struct IsArrayHelper<T[]> : TrueType {}; + +} // namespace detail + +/** + * IsArray determines whether a type is an array type, of known or unknown + * length. + * + * mozilla::IsArray<int>::value is false; + * mozilla::IsArray<int[]>::value is true; + * mozilla::IsArray<int[5]>::value is true. + */ +template<typename T> +struct IsArray : detail::IsArrayHelper<typename RemoveCV<T>::Type> +{}; + +namespace detail { + +template<typename T> +struct IsFunPtr; + +template<typename> +struct IsFunPtr + : public FalseType +{}; + +template<typename Result, typename... ArgTypes> +struct IsFunPtr<Result(*)(ArgTypes...)> + : public TrueType +{}; + +}; // namespace detail + +/** + * IsFunction determines whether a type is a function type. Function pointers + * don't qualify here--only the type of an actual function symbol. We do not + * correctly handle varags function types because of a bug in MSVC. + * + * Given the function: + * void f(int) {} + * + * mozilla::IsFunction<void(int)> is true; + * mozilla::IsFunction<void(*)(int)> is false; + * mozilla::IsFunction<decltype(f)> is true. + */ +template<typename T> +struct IsFunction + : public detail::IsFunPtr<typename RemoveCV<T>::Type *> +{}; + +namespace detail { + +template<typename T> +struct IsPointerHelper : FalseType {}; + +template<typename T> +struct IsPointerHelper<T*> : TrueType {}; + +} // namespace detail + +/** + * IsPointer determines whether a type is a possibly-CV-qualified pointer type + * (but not a pointer-to-member type). + * + * mozilla::IsPointer<struct S*>::value is true; + * mozilla::IsPointer<int*>::value is true; + * mozilla::IsPointer<int**>::value is true; + * mozilla::IsPointer<const int*>::value is true; + * mozilla::IsPointer<int* const>::value is true; + * mozilla::IsPointer<int* volatile>::value is true; + * mozilla::IsPointer<void (*)(void)>::value is true; + * mozilla::IsPointer<int>::value is false; + * mozilla::IsPointer<struct S>::value is false. + * mozilla::IsPointer<int(struct S::*)>::value is false + */ +template<typename T> +struct IsPointer : detail::IsPointerHelper<typename RemoveCV<T>::Type> +{}; + +/** + * IsLvalueReference determines whether a type is an lvalue reference. + * + * mozilla::IsLvalueReference<struct S*>::value is false; + * mozilla::IsLvalueReference<int**>::value is false; + * mozilla::IsLvalueReference<void (*)(void)>::value is false; + * mozilla::IsLvalueReference<int>::value is false; + * mozilla::IsLvalueReference<struct S>::value is false; + * mozilla::IsLvalueReference<struct S*&>::value is true; + * mozilla::IsLvalueReference<struct S&&>::value is false. + */ +template<typename T> +struct IsLvalueReference : FalseType {}; + +template<typename T> +struct IsLvalueReference<T&> : TrueType {}; + +/** + * IsRvalueReference determines whether a type is an rvalue reference. + * + * mozilla::IsRvalueReference<struct S*>::value is false; + * mozilla::IsRvalueReference<int**>::value is false; + * mozilla::IsRvalueReference<void (*)(void)>::value is false; + * mozilla::IsRvalueReference<int>::value is false; + * mozilla::IsRvalueReference<struct S>::value is false; + * mozilla::IsRvalueReference<struct S*&>::value is false; + * mozilla::IsRvalueReference<struct S&&>::value is true. + */ +template<typename T> +struct IsRvalueReference : FalseType {}; + +template<typename T> +struct IsRvalueReference<T&&> : TrueType {}; + +namespace detail { + +// __is_enum is a supported extension across all of our supported compilers. +template<typename T> +struct IsEnumHelper + : IntegralConstant<bool, __is_enum(T)> +{}; + +} // namespace detail + +/** + * IsEnum determines whether a type is an enum type. + * + * mozilla::IsEnum<enum S>::value is true; + * mozilla::IsEnum<enum S*>::value is false; + * mozilla::IsEnum<int>::value is false; + */ +template<typename T> +struct IsEnum + : detail::IsEnumHelper<typename RemoveCV<T>::Type> +{}; + +namespace detail { + +// __is_class is a supported extension across all of our supported compilers: +// http://llvm.org/releases/3.0/docs/ClangReleaseNotes.html +// http://gcc.gnu.org/onlinedocs/gcc-4.4.7/gcc/Type-Traits.html#Type-Traits +// http://msdn.microsoft.com/en-us/library/ms177194%28v=vs.100%29.aspx +template<typename T> +struct IsClassHelper + : IntegralConstant<bool, __is_class(T)> +{}; + +} // namespace detail + +/** + * IsClass determines whether a type is a class type (but not a union). + * + * struct S {}; + * union U {}; + * mozilla::IsClass<int>::value is false; + * mozilla::IsClass<const S>::value is true; + * mozilla::IsClass<U>::value is false; + */ +template<typename T> +struct IsClass + : detail::IsClassHelper<typename RemoveCV<T>::Type> +{}; + +/* 20.9.4.2 Composite type traits [meta.unary.comp] */ + +/** + * IsReference determines whether a type is an lvalue or rvalue reference. + * + * mozilla::IsReference<struct S*>::value is false; + * mozilla::IsReference<int**>::value is false; + * mozilla::IsReference<int&>::value is true; + * mozilla::IsReference<void (*)(void)>::value is false; + * mozilla::IsReference<const int&>::value is true; + * mozilla::IsReference<int>::value is false; + * mozilla::IsReference<struct S>::value is false; + * mozilla::IsReference<struct S&>::value is true; + * mozilla::IsReference<struct S*&>::value is true; + * mozilla::IsReference<struct S&&>::value is true. + */ +template<typename T> +struct IsReference + : IntegralConstant<bool, + IsLvalueReference<T>::value || IsRvalueReference<T>::value> +{}; + +/** + * IsArithmetic determines whether a type is arithmetic. A type is arithmetic + * iff it is an integral type or a floating point type. + * + * mozilla::IsArithmetic<int>::value is true; + * mozilla::IsArithmetic<double>::value is true; + * mozilla::IsArithmetic<long double*>::value is false. + */ +template<typename T> +struct IsArithmetic + : IntegralConstant<bool, IsIntegral<T>::value || IsFloatingPoint<T>::value> +{}; + +namespace detail { + +template<typename T> +struct IsMemberPointerHelper : FalseType {}; + +template<typename T, typename U> +struct IsMemberPointerHelper<T U::*> : TrueType {}; + +} // namespace detail + +/** + * IsMemberPointer determines whether a type is pointer to non-static member + * object or a pointer to non-static member function. + * + * mozilla::IsMemberPointer<int(cls::*)>::value is true + * mozilla::IsMemberPointer<int*>::value is false + */ +template<typename T> +struct IsMemberPointer + : detail::IsMemberPointerHelper<typename RemoveCV<T>::Type> +{}; + +/** + * IsScalar determines whether a type is a scalar type. + * + * mozilla::IsScalar<int>::value is true + * mozilla::IsScalar<int*>::value is true + * mozilla::IsScalar<cls>::value is false + */ +template<typename T> +struct IsScalar + : IntegralConstant<bool, IsArithmetic<T>::value || IsEnum<T>::value || + IsPointer<T>::value || IsMemberPointer<T>::value> +{}; + +/* 20.9.4.3 Type properties [meta.unary.prop] */ + +/** + * IsConst determines whether a type is const or not. + * + * mozilla::IsConst<int>::value is false; + * mozilla::IsConst<void* const>::value is true; + * mozilla::IsConst<const char*>::value is false. + */ +template<typename T> +struct IsConst : FalseType {}; + +template<typename T> +struct IsConst<const T> : TrueType {}; + +/** + * IsVolatile determines whether a type is volatile or not. + * + * mozilla::IsVolatile<int>::value is false; + * mozilla::IsVolatile<void* volatile>::value is true; + * mozilla::IsVolatile<volatile char*>::value is false. + */ +template<typename T> +struct IsVolatile : FalseType {}; + +template<typename T> +struct IsVolatile<volatile T> : TrueType {}; + +/** + * Traits class for identifying POD types. Until C++11 there's no automatic + * way to detect PODs, so for the moment this is done manually. Users may + * define specializations of this class that inherit from mozilla::TrueType and + * mozilla::FalseType (or equivalently mozilla::IntegralConstant<bool, true or + * false>, or conveniently from mozilla::IsPod for composite types) as needed to + * ensure correct IsPod behavior. + */ +template<typename T> +struct IsPod : public FalseType {}; + +template<> struct IsPod<char> : TrueType {}; +template<> struct IsPod<signed char> : TrueType {}; +template<> struct IsPod<unsigned char> : TrueType {}; +template<> struct IsPod<short> : TrueType {}; +template<> struct IsPod<unsigned short> : TrueType {}; +template<> struct IsPod<int> : TrueType {}; +template<> struct IsPod<unsigned int> : TrueType {}; +template<> struct IsPod<long> : TrueType {}; +template<> struct IsPod<unsigned long> : TrueType {}; +template<> struct IsPod<long long> : TrueType {}; +template<> struct IsPod<unsigned long long> : TrueType {}; +template<> struct IsPod<bool> : TrueType {}; +template<> struct IsPod<float> : TrueType {}; +template<> struct IsPod<double> : TrueType {}; +template<> struct IsPod<wchar_t> : TrueType {}; +template<> struct IsPod<char16_t> : TrueType {}; +template<typename T> struct IsPod<T*> : TrueType {}; + +namespace detail { + +// __is_empty is a supported extension across all of our supported compilers: +// http://llvm.org/releases/3.0/docs/ClangReleaseNotes.html +// http://gcc.gnu.org/onlinedocs/gcc-4.4.7/gcc/Type-Traits.html#Type-Traits +// http://msdn.microsoft.com/en-us/library/ms177194%28v=vs.100%29.aspx +template<typename T> +struct IsEmptyHelper + : IntegralConstant<bool, IsClass<T>::value && __is_empty(T)> +{}; + +} // namespace detail + +/** + * IsEmpty determines whether a type is a class (but not a union) that is empty. + * + * A class is empty iff it and all its base classes have no non-static data + * members (except bit-fields of length 0) and no virtual member functions, and + * no base class is empty or a virtual base class. + * + * Intuitively, empty classes don't have any data that has to be stored in + * instances of those classes. (The size of the class must still be non-zero, + * because distinct array elements of any type must have different addresses. + * However, if the Empty Base Optimization is implemented by the compiler [most + * compilers implement it, and in certain cases C++11 requires it], the size of + * a class inheriting from an empty |Base| class need not be inflated by + * |sizeof(Base)|.) And intuitively, non-empty classes have data members and/or + * vtable pointers that must be stored in each instance for proper behavior. + * + * static_assert(!mozilla::IsEmpty<int>::value, "not a class => not empty"); + * union U1 { int x; }; + * static_assert(!mozilla::IsEmpty<U1>::value, "not a class => not empty"); + * struct E1 {}; + * struct E2 { int : 0 }; + * struct E3 : E1 {}; + * struct E4 : E2 {}; + * static_assert(mozilla::IsEmpty<E1>::value && + * mozilla::IsEmpty<E2>::value && + * mozilla::IsEmpty<E3>::value && + * mozilla::IsEmpty<E4>::value, + * "all empty"); + * union U2 { E1 e1; }; + * static_assert(!mozilla::IsEmpty<U2>::value, "not a class => not empty"); + * struct NE1 { int x; }; + * struct NE2 : virtual E1 {}; + * struct NE3 : E2 { virtual ~NE3() {} }; + * struct NE4 { virtual void f() {} }; + * static_assert(!mozilla::IsEmpty<NE1>::value && + * !mozilla::IsEmpty<NE2>::value && + * !mozilla::IsEmpty<NE3>::value && + * !mozilla::IsEmpty<NE4>::value, + * "all empty"); + */ +template<typename T> +struct IsEmpty : detail::IsEmptyHelper<typename RemoveCV<T>::Type> +{}; + + +namespace detail { + +template<typename T, + bool = IsFloatingPoint<T>::value, + bool = IsIntegral<T>::value, + typename NoCV = typename RemoveCV<T>::Type> +struct IsSignedHelper; + +// Floating point is signed. +template<typename T, typename NoCV> +struct IsSignedHelper<T, true, false, NoCV> : TrueType {}; + +// Integral is conditionally signed. +template<typename T, typename NoCV> +struct IsSignedHelper<T, false, true, NoCV> + : IntegralConstant<bool, bool(NoCV(-1) < NoCV(1))> +{}; + +// Non-floating point, non-integral is not signed. +template<typename T, typename NoCV> +struct IsSignedHelper<T, false, false, NoCV> : FalseType {}; + +} // namespace detail + +/** + * IsSigned determines whether a type is a signed arithmetic type. |char| is + * considered a signed type if it has the same representation as |signed char|. + * + * mozilla::IsSigned<int>::value is true; + * mozilla::IsSigned<const unsigned int>::value is false; + * mozilla::IsSigned<unsigned char>::value is false; + * mozilla::IsSigned<float>::value is true. + */ +template<typename T> +struct IsSigned : detail::IsSignedHelper<T> {}; + +namespace detail { + +template<typename T, + bool = IsFloatingPoint<T>::value, + bool = IsIntegral<T>::value, + typename NoCV = typename RemoveCV<T>::Type> +struct IsUnsignedHelper; + +// Floating point is not unsigned. +template<typename T, typename NoCV> +struct IsUnsignedHelper<T, true, false, NoCV> : FalseType {}; + +// Integral is conditionally unsigned. +template<typename T, typename NoCV> +struct IsUnsignedHelper<T, false, true, NoCV> + : IntegralConstant<bool, + (IsSame<NoCV, bool>::value || bool(NoCV(1) < NoCV(-1)))> +{}; + +// Non-floating point, non-integral is not unsigned. +template<typename T, typename NoCV> +struct IsUnsignedHelper<T, false, false, NoCV> : FalseType {}; + +} // namespace detail + +/** + * IsUnsigned determines whether a type is an unsigned arithmetic type. + * + * mozilla::IsUnsigned<int>::value is false; + * mozilla::IsUnsigned<const unsigned int>::value is true; + * mozilla::IsUnsigned<unsigned char>::value is true; + * mozilla::IsUnsigned<float>::value is false. + */ +template<typename T> +struct IsUnsigned : detail::IsUnsignedHelper<T> {}; + +namespace detail { + +struct DoIsDestructibleImpl +{ + template<typename T, typename = decltype(DeclVal<T&>().~T())> + static TrueType test(int); + template<typename T> + static FalseType test(...); +}; + +template<typename T> +struct IsDestructibleImpl : public DoIsDestructibleImpl +{ + typedef decltype(test<T>(0)) Type; +}; + +} // namespace detail + +template<typename T> +struct IsDestructible : public detail::IsDestructibleImpl<T>::Type {}; + +/* 20.9.5 Type property queries [meta.unary.prop.query] */ + +/* 20.9.6 Relationships between types [meta.rel] */ + +/** + * IsSame tests whether two types are the same type. + * + * mozilla::IsSame<int, int>::value is true; + * mozilla::IsSame<int*, int*>::value is true; + * mozilla::IsSame<int, unsigned int>::value is false; + * mozilla::IsSame<void, void>::value is true; + * mozilla::IsSame<const int, int>::value is false; + * mozilla::IsSame<struct S, struct S>::value is true. + */ +template<typename T, typename U> +struct IsSame : FalseType {}; + +template<typename T> +struct IsSame<T, T> : TrueType {}; + +namespace detail { + +#if defined(__GNUC__) || defined(__clang__) || defined(_MSC_VER) + +template<class Base, class Derived> +struct BaseOfTester : IntegralConstant<bool, __is_base_of(Base, Derived)> {}; + +#else + +// The trickery used to implement IsBaseOf here makes it possible to use it for +// the cases of private and multiple inheritance. This code was inspired by the +// sample code here: +// +// http://stackoverflow.com/questions/2910979/how-is-base-of-works +template<class Base, class Derived> +struct BaseOfHelper +{ +public: + operator Base*() const; + operator Derived*(); +}; + +template<class Base, class Derived> +struct BaseOfTester +{ +private: + template<class T> + static char test(Derived*, T); + static int test(Base*, int); + +public: + static const bool value = + sizeof(test(BaseOfHelper<Base, Derived>(), int())) == sizeof(char); +}; + +template<class Base, class Derived> +struct BaseOfTester<Base, const Derived> +{ +private: + template<class T> + static char test(Derived*, T); + static int test(Base*, int); + +public: + static const bool value = + sizeof(test(BaseOfHelper<Base, Derived>(), int())) == sizeof(char); +}; + +template<class Base, class Derived> +struct BaseOfTester<Base&, Derived&> : FalseType {}; + +template<class Type> +struct BaseOfTester<Type, Type> : TrueType {}; + +template<class Type> +struct BaseOfTester<Type, const Type> : TrueType {}; + +#endif + +} /* namespace detail */ + +/* + * IsBaseOf allows to know whether a given class is derived from another. + * + * Consider the following class definitions: + * + * class A {}; + * class B : public A {}; + * class C {}; + * + * mozilla::IsBaseOf<A, B>::value is true; + * mozilla::IsBaseOf<A, C>::value is false; + */ +template<class Base, class Derived> +struct IsBaseOf + : IntegralConstant<bool, detail::BaseOfTester<Base, Derived>::value> +{}; + +namespace detail { + +template<typename From, typename To> +struct ConvertibleTester +{ +private: + template<typename To1> + static char test_helper(To1); + + template<typename From1, typename To1> + static decltype(test_helper<To1>(DeclVal<From1>())) test(int); + + template<typename From1, typename To1> + static int test(...); + +public: + static const bool value = + sizeof(test<From, To>(0)) == sizeof(char); +}; + +} // namespace detail + +/** + * IsConvertible determines whether a value of type From will implicitly convert + * to a value of type To. For example: + * + * struct A {}; + * struct B : public A {}; + * struct C {}; + * + * mozilla::IsConvertible<A, A>::value is true; + * mozilla::IsConvertible<A*, A*>::value is true; + * mozilla::IsConvertible<B, A>::value is true; + * mozilla::IsConvertible<B*, A*>::value is true; + * mozilla::IsConvertible<C, A>::value is false; + * mozilla::IsConvertible<A, C>::value is false; + * mozilla::IsConvertible<A*, C*>::value is false; + * mozilla::IsConvertible<C*, A*>::value is false. + * + * For obscure reasons, you can't use IsConvertible when the types being tested + * are related through private inheritance, and you'll get a compile error if + * you try. Just don't do it! + * + * Note - we need special handling for void, which ConvertibleTester doesn't + * handle. The void handling here doesn't handle const/volatile void correctly, + * which could be easily fixed if the need arises. + */ +template<typename From, typename To> +struct IsConvertible + : IntegralConstant<bool, detail::ConvertibleTester<From, To>::value> +{}; + +template<typename B> +struct IsConvertible<void, B> + : IntegralConstant<bool, IsVoid<B>::value> +{}; + +template<typename A> +struct IsConvertible<A, void> + : IntegralConstant<bool, IsVoid<A>::value> +{}; + +template<> +struct IsConvertible<void, void> + : TrueType +{}; + +/* 20.9.7 Transformations between types [meta.trans] */ + +/* 20.9.7.1 Const-volatile modifications [meta.trans.cv] */ + +/** + * RemoveConst removes top-level const qualifications on a type. + * + * mozilla::RemoveConst<int>::Type is int; + * mozilla::RemoveConst<const int>::Type is int; + * mozilla::RemoveConst<const int*>::Type is const int*; + * mozilla::RemoveConst<int* const>::Type is int*. + */ +template<typename T> +struct RemoveConst +{ + typedef T Type; +}; + +template<typename T> +struct RemoveConst<const T> +{ + typedef T Type; +}; + +/** + * RemoveVolatile removes top-level volatile qualifications on a type. + * + * mozilla::RemoveVolatile<int>::Type is int; + * mozilla::RemoveVolatile<volatile int>::Type is int; + * mozilla::RemoveVolatile<volatile int*>::Type is volatile int*; + * mozilla::RemoveVolatile<int* volatile>::Type is int*. + */ +template<typename T> +struct RemoveVolatile +{ + typedef T Type; +}; + +template<typename T> +struct RemoveVolatile<volatile T> +{ + typedef T Type; +}; + +/** + * RemoveCV removes top-level const and volatile qualifications on a type. + * + * mozilla::RemoveCV<int>::Type is int; + * mozilla::RemoveCV<const int>::Type is int; + * mozilla::RemoveCV<volatile int>::Type is int; + * mozilla::RemoveCV<int* const volatile>::Type is int*. + */ +template<typename T> +struct RemoveCV +{ + typedef typename RemoveConst<typename RemoveVolatile<T>::Type>::Type Type; +}; + +/* 20.9.7.2 Reference modifications [meta.trans.ref] */ + +/** + * Converts reference types to the underlying types. + * + * mozilla::RemoveReference<T>::Type is T; + * mozilla::RemoveReference<T&>::Type is T; + * mozilla::RemoveReference<T&&>::Type is T; + */ + +template<typename T> +struct RemoveReference +{ + typedef T Type; +}; + +template<typename T> +struct RemoveReference<T&> +{ + typedef T Type; +}; + +template<typename T> +struct RemoveReference<T&&> +{ + typedef T Type; +}; + +template<bool Condition, typename A, typename B> +struct Conditional; + +namespace detail { + +enum Voidness { TIsVoid, TIsNotVoid }; + +template<typename T, Voidness V = IsVoid<T>::value ? TIsVoid : TIsNotVoid> +struct AddLvalueReferenceHelper; + +template<typename T> +struct AddLvalueReferenceHelper<T, TIsVoid> +{ + typedef void Type; +}; + +template<typename T> +struct AddLvalueReferenceHelper<T, TIsNotVoid> +{ + typedef T& Type; +}; + +} // namespace detail + +/** + * AddLvalueReference adds an lvalue & reference to T if one isn't already + * present. (Note: adding an lvalue reference to an rvalue && reference in + * essence replaces the && with a &&, per C+11 reference collapsing rules. For + * example, int&& would become int&.) + * + * The final computed type will only *not* be an lvalue reference if T is void. + * + * mozilla::AddLvalueReference<int>::Type is int&; + * mozilla::AddLvalueRference<volatile int&>::Type is volatile int&; + * mozilla::AddLvalueReference<void*>::Type is void*&; + * mozilla::AddLvalueReference<void>::Type is void; + * mozilla::AddLvalueReference<struct S&&>::Type is struct S&. + */ +template<typename T> +struct AddLvalueReference + : detail::AddLvalueReferenceHelper<T> +{}; + +namespace detail { + +template<typename T, Voidness V = IsVoid<T>::value ? TIsVoid : TIsNotVoid> +struct AddRvalueReferenceHelper; + +template<typename T> +struct AddRvalueReferenceHelper<T, TIsVoid> +{ + typedef void Type; +}; + +template<typename T> +struct AddRvalueReferenceHelper<T, TIsNotVoid> +{ + typedef T&& Type; +}; + +} // namespace detail + +/** + * AddRvalueReference adds an rvalue && reference to T if one isn't already + * present. (Note: adding an rvalue reference to an lvalue & reference in + * essence keeps the &, per C+11 reference collapsing rules. For example, + * int& would remain int&.) + * + * The final computed type will only *not* be a reference if T is void. + * + * mozilla::AddRvalueReference<int>::Type is int&&; + * mozilla::AddRvalueRference<volatile int&>::Type is volatile int&; + * mozilla::AddRvalueRference<const int&&>::Type is const int&&; + * mozilla::AddRvalueReference<void*>::Type is void*&&; + * mozilla::AddRvalueReference<void>::Type is void; + * mozilla::AddRvalueReference<struct S&>::Type is struct S&. + */ +template<typename T> +struct AddRvalueReference + : detail::AddRvalueReferenceHelper<T> +{}; + +/* 20.9.7.3 Sign modifications [meta.trans.sign] */ + +template<bool B, typename T = void> +struct EnableIf; + +namespace detail { + +template<bool MakeConst, typename T> +struct WithC : Conditional<MakeConst, const T, T> +{}; + +template<bool MakeVolatile, typename T> +struct WithV : Conditional<MakeVolatile, volatile T, T> +{}; + + +template<bool MakeConst, bool MakeVolatile, typename T> +struct WithCV : WithC<MakeConst, typename WithV<MakeVolatile, T>::Type> +{}; + +template<typename T> +struct CorrespondingSigned; + +template<> +struct CorrespondingSigned<char> { typedef signed char Type; }; +template<> +struct CorrespondingSigned<unsigned char> { typedef signed char Type; }; +template<> +struct CorrespondingSigned<unsigned short> { typedef short Type; }; +template<> +struct CorrespondingSigned<unsigned int> { typedef int Type; }; +template<> +struct CorrespondingSigned<unsigned long> { typedef long Type; }; +template<> +struct CorrespondingSigned<unsigned long long> { typedef long long Type; }; + +template<typename T, + typename CVRemoved = typename RemoveCV<T>::Type, + bool IsSignedIntegerType = IsSigned<CVRemoved>::value && + !IsSame<char, CVRemoved>::value> +struct MakeSigned; + +template<typename T, typename CVRemoved> +struct MakeSigned<T, CVRemoved, true> +{ + typedef T Type; +}; + +template<typename T, typename CVRemoved> +struct MakeSigned<T, CVRemoved, false> + : WithCV<IsConst<T>::value, IsVolatile<T>::value, + typename CorrespondingSigned<CVRemoved>::Type> +{}; + +} // namespace detail + +/** + * MakeSigned produces the corresponding signed integer type for a given + * integral type T, with the const/volatile qualifiers of T. T must be a + * possibly-const/volatile-qualified integral type that isn't bool. + * + * If T is already a signed integer type (not including char!), then T is + * produced. + * + * Otherwise, if T is an unsigned integer type, the signed variety of T, with + * T's const/volatile qualifiers, is produced. + * + * Otherwise, the integral type of the same size as T, with the lowest rank, + * with T's const/volatile qualifiers, is produced. (This basically only acts + * to produce signed char when T = char.) + * + * mozilla::MakeSigned<unsigned long>::Type is signed long; + * mozilla::MakeSigned<volatile int>::Type is volatile int; + * mozilla::MakeSigned<const unsigned short>::Type is const signed short; + * mozilla::MakeSigned<const char>::Type is const signed char; + * mozilla::MakeSigned<bool> is an error; + * mozilla::MakeSigned<void*> is an error. + */ +template<typename T> +struct MakeSigned + : EnableIf<IsIntegral<T>::value && + !IsSame<bool, typename RemoveCV<T>::Type>::value, + typename detail::MakeSigned<T> + >::Type +{}; + +namespace detail { + +template<typename T> +struct CorrespondingUnsigned; + +template<> +struct CorrespondingUnsigned<char> { typedef unsigned char Type; }; +template<> +struct CorrespondingUnsigned<signed char> { typedef unsigned char Type; }; +template<> +struct CorrespondingUnsigned<short> { typedef unsigned short Type; }; +template<> +struct CorrespondingUnsigned<int> { typedef unsigned int Type; }; +template<> +struct CorrespondingUnsigned<long> { typedef unsigned long Type; }; +template<> +struct CorrespondingUnsigned<long long> { typedef unsigned long long Type; }; + + +template<typename T, + typename CVRemoved = typename RemoveCV<T>::Type, + bool IsUnsignedIntegerType = IsUnsigned<CVRemoved>::value && + !IsSame<char, CVRemoved>::value> +struct MakeUnsigned; + +template<typename T, typename CVRemoved> +struct MakeUnsigned<T, CVRemoved, true> +{ + typedef T Type; +}; + +template<typename T, typename CVRemoved> +struct MakeUnsigned<T, CVRemoved, false> + : WithCV<IsConst<T>::value, IsVolatile<T>::value, + typename CorrespondingUnsigned<CVRemoved>::Type> +{}; + +} // namespace detail + +/** + * MakeUnsigned produces the corresponding unsigned integer type for a given + * integral type T, with the const/volatile qualifiers of T. T must be a + * possibly-const/volatile-qualified integral type that isn't bool. + * + * If T is already an unsigned integer type (not including char!), then T is + * produced. + * + * Otherwise, if T is an signed integer type, the unsigned variety of T, with + * T's const/volatile qualifiers, is produced. + * + * Otherwise, the unsigned integral type of the same size as T, with the lowest + * rank, with T's const/volatile qualifiers, is produced. (This basically only + * acts to produce unsigned char when T = char.) + * + * mozilla::MakeUnsigned<signed long>::Type is unsigned long; + * mozilla::MakeUnsigned<volatile unsigned int>::Type is volatile unsigned int; + * mozilla::MakeUnsigned<const signed short>::Type is const unsigned short; + * mozilla::MakeUnsigned<const char>::Type is const unsigned char; + * mozilla::MakeUnsigned<bool> is an error; + * mozilla::MakeUnsigned<void*> is an error. + */ +template<typename T> +struct MakeUnsigned + : EnableIf<IsIntegral<T>::value && + !IsSame<bool, typename RemoveCV<T>::Type>::value, + typename detail::MakeUnsigned<T> + >::Type +{}; + +/* 20.9.7.4 Array modifications [meta.trans.arr] */ + +/** + * RemoveExtent produces either the type of the elements of the array T, or T + * itself. + * + * mozilla::RemoveExtent<int>::Type is int; + * mozilla::RemoveExtent<const int[]>::Type is const int; + * mozilla::RemoveExtent<volatile int[5]>::Type is volatile int; + * mozilla::RemoveExtent<long[][17]>::Type is long[17]. + */ +template<typename T> +struct RemoveExtent +{ + typedef T Type; +}; + +template<typename T> +struct RemoveExtent<T[]> +{ + typedef T Type; +}; + +template<typename T, decltype(sizeof(1)) N> +struct RemoveExtent<T[N]> +{ + typedef T Type; +}; + +/* 20.9.7.5 Pointer modifications [meta.trans.ptr] */ + +namespace detail { + +template<typename T, typename CVRemoved> +struct RemovePointerHelper +{ + typedef T Type; +}; + +template<typename T, typename Pointee> +struct RemovePointerHelper<T, Pointee*> +{ + typedef Pointee Type; +}; + +} // namespace detail + +/** + * Produces the pointed-to type if a pointer is provided, else returns the input + * type. Note that this does not dereference pointer-to-member pointers. + * + * struct S { bool m; void f(); }; + * mozilla::RemovePointer<int>::Type is int; + * mozilla::RemovePointer<int*>::Type is int; + * mozilla::RemovePointer<int* const>::Type is int; + * mozilla::RemovePointer<int* volatile>::Type is int; + * mozilla::RemovePointer<const long*>::Type is const long; + * mozilla::RemovePointer<void* const>::Type is void; + * mozilla::RemovePointer<void (S::*)()>::Type is void (S::*)(); + * mozilla::RemovePointer<void (*)()>::Type is void(); + * mozilla::RemovePointer<bool S::*>::Type is bool S::*. + */ +template<typename T> +struct RemovePointer + : detail::RemovePointerHelper<T, typename RemoveCV<T>::Type> +{}; + +/** + * Converts T& to T*. Otherwise returns T* given T. Note that C++17 wants + * std::add_pointer to work differently for function types. We don't implement + * that behavior here. + * + * mozilla::AddPointer<int> is int*; + * mozilla::AddPointer<int*> is int**; + * mozilla::AddPointer<int&> is int*; + * mozilla::AddPointer<int* const> is int** const. + */ +template<typename T> +struct AddPointer +{ + typedef typename RemoveReference<T>::Type* Type; +}; + +/* 20.9.7.6 Other transformations [meta.trans.other] */ + +/** + * EnableIf is a struct containing a typedef of T if and only if B is true. + * + * mozilla::EnableIf<true, int>::Type is int; + * mozilla::EnableIf<false, int>::Type is a compile-time error. + * + * Use this template to implement SFINAE-style (Substitution Failure Is not An + * Error) requirements. For example, you might use it to impose a restriction + * on a template parameter: + * + * template<typename T> + * class PodVector // vector optimized to store POD (memcpy-able) types + * { + * EnableIf<IsPod<T>::value, T>::Type* vector; + * size_t length; + * ... + * }; + */ +template<bool B, typename T> +struct EnableIf +{}; + +template<typename T> +struct EnableIf<true, T> +{ + typedef T Type; +}; + +/** + * Conditional selects a class between two, depending on a given boolean value. + * + * mozilla::Conditional<true, A, B>::Type is A; + * mozilla::Conditional<false, A, B>::Type is B; + */ +template<bool Condition, typename A, typename B> +struct Conditional +{ + typedef A Type; +}; + +template<class A, class B> +struct Conditional<false, A, B> +{ + typedef B Type; +}; + +namespace detail { + +template<typename U, + bool IsArray = IsArray<U>::value, + bool IsFunction = IsFunction<U>::value> +struct DecaySelector; + +template<typename U> +struct DecaySelector<U, false, false> +{ + typedef typename RemoveCV<U>::Type Type; +}; + +template<typename U> +struct DecaySelector<U, true, false> +{ + typedef typename RemoveExtent<U>::Type* Type; +}; + +template<typename U> +struct DecaySelector<U, false, true> +{ + typedef typename AddPointer<U>::Type Type; +}; + +}; // namespace detail + +/** + * Strips const/volatile off a type and decays it from an lvalue to an + * rvalue. So function types are converted to function pointers, arrays to + * pointers, and references are removed. + * + * mozilla::Decay<int>::Type is int + * mozilla::Decay<int&>::Type is int + * mozilla::Decay<int&&>::Type is int + * mozilla::Decay<const int&>::Type is int + * mozilla::Decay<int[2]>::Type is int* + * mozilla::Decay<int(int)>::Type is int(*)(int) + */ +template<typename T> +class Decay + : public detail::DecaySelector<typename RemoveReference<T>::Type> +{ +}; + +} /* namespace mozilla */ + +#endif /* mozilla_TypeTraits_h */ diff --git a/mfbt/TypedEnumBits.h b/mfbt/TypedEnumBits.h new file mode 100644 index 000000000..5ee6315c8 --- /dev/null +++ b/mfbt/TypedEnumBits.h @@ -0,0 +1,156 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* + * MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS allows using a typed enum as bit flags. + */ + +#ifndef mozilla_TypedEnumBits_h +#define mozilla_TypedEnumBits_h + +#include "mozilla/Attributes.h" +#include "mozilla/IntegerTypeTraits.h" + +namespace mozilla { + +/* + * The problem that CastableTypedEnumResult aims to solve is that + * typed enums are not convertible to bool, and there is no way to make them + * be, yet user code wants to be able to write + * + * if (myFlags & Flags::SOME_PARTICULAR_FLAG) (1) + * + * There are different approaches to solving this. Most of them require + * adapting user code. For example, we could implement operator! and have + * the user write + * + * if (!!(myFlags & Flags::SOME_PARTICULAR_FLAG)) (2) + * + * Or we could supply a IsNonZero() or Any() function returning whether + * an enum value is nonzero, and have the user write + * + * if (Any(Flags & Flags::SOME_PARTICULAR_FLAG)) (3) + * + * But instead, we choose to preserve the original user syntax (1) as it + * is inherently more readable, and to ease porting existing code to typed + * enums. We achieve this by having operator& and other binary bitwise + * operators have as return type a class, CastableTypedEnumResult, + * that wraps a typed enum but adds bool convertibility. + */ +template<typename E> +class CastableTypedEnumResult +{ +private: + const E mValue; + +public: + explicit constexpr CastableTypedEnumResult(E aValue) + : mValue(aValue) + {} + + constexpr operator E() const { return mValue; } + + template<typename DestinationType> + explicit constexpr + operator DestinationType() const { return DestinationType(mValue); } + + constexpr bool operator !() const { return !bool(mValue); } +}; + +#define MOZ_CASTABLETYPEDENUMRESULT_BINOP(Op, OtherType, ReturnType) \ +template<typename E> \ +constexpr ReturnType \ +operator Op(const OtherType& aE, const CastableTypedEnumResult<E>& aR) \ +{ \ + return ReturnType(aE Op OtherType(aR)); \ +} \ +template<typename E> \ +constexpr ReturnType \ +operator Op(const CastableTypedEnumResult<E>& aR, const OtherType& aE) \ +{ \ + return ReturnType(OtherType(aR) Op aE); \ +} \ +template<typename E> \ +constexpr ReturnType \ +operator Op(const CastableTypedEnumResult<E>& aR1, \ + const CastableTypedEnumResult<E>& aR2) \ +{ \ + return ReturnType(OtherType(aR1) Op OtherType(aR2)); \ +} + +MOZ_CASTABLETYPEDENUMRESULT_BINOP(|, E, CastableTypedEnumResult<E>) +MOZ_CASTABLETYPEDENUMRESULT_BINOP(&, E, CastableTypedEnumResult<E>) +MOZ_CASTABLETYPEDENUMRESULT_BINOP(^, E, CastableTypedEnumResult<E>) +MOZ_CASTABLETYPEDENUMRESULT_BINOP(==, E, bool) +MOZ_CASTABLETYPEDENUMRESULT_BINOP(!=, E, bool) +MOZ_CASTABLETYPEDENUMRESULT_BINOP(||, bool, bool) +MOZ_CASTABLETYPEDENUMRESULT_BINOP(&&, bool, bool) + +template <typename E> +constexpr CastableTypedEnumResult<E> +operator ~(const CastableTypedEnumResult<E>& aR) +{ + return CastableTypedEnumResult<E>(~(E(aR))); +} + +#define MOZ_CASTABLETYPEDENUMRESULT_COMPOUND_ASSIGN_OP(Op) \ +template<typename E> \ +E& \ +operator Op(E& aR1, \ + const CastableTypedEnumResult<E>& aR2) \ +{ \ + return aR1 Op E(aR2); \ +} + +MOZ_CASTABLETYPEDENUMRESULT_COMPOUND_ASSIGN_OP(&=) +MOZ_CASTABLETYPEDENUMRESULT_COMPOUND_ASSIGN_OP(|=) +MOZ_CASTABLETYPEDENUMRESULT_COMPOUND_ASSIGN_OP(^=) + +#undef MOZ_CASTABLETYPEDENUMRESULT_COMPOUND_ASSIGN_OP + +#undef MOZ_CASTABLETYPEDENUMRESULT_BINOP + +namespace detail { +template<typename E> +struct UnsignedIntegerTypeForEnum + : UnsignedStdintTypeForSize<sizeof(E)> +{}; +} // namespace detail + +} // namespace mozilla + +#define MOZ_MAKE_ENUM_CLASS_BINOP_IMPL(Name, Op) \ + inline constexpr mozilla::CastableTypedEnumResult<Name> \ + operator Op(Name a, Name b) \ + { \ + typedef mozilla::CastableTypedEnumResult<Name> Result; \ + typedef mozilla::detail::UnsignedIntegerTypeForEnum<Name>::Type U; \ + return Result(Name(U(a) Op U(b))); \ + } \ + \ + inline Name& \ + operator Op##=(Name& a, Name b) \ + { \ + return a = a Op b; \ + } + +/** + * MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS generates standard bitwise operators + * for the given enum type. Use this to enable using an enum type as bit-field. + */ +#define MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(Name) \ + MOZ_MAKE_ENUM_CLASS_BINOP_IMPL(Name, |) \ + MOZ_MAKE_ENUM_CLASS_BINOP_IMPL(Name, &) \ + MOZ_MAKE_ENUM_CLASS_BINOP_IMPL(Name, ^) \ + inline constexpr mozilla::CastableTypedEnumResult<Name> \ + operator~(Name a) \ + { \ + typedef mozilla::CastableTypedEnumResult<Name> Result; \ + typedef mozilla::detail::UnsignedIntegerTypeForEnum<Name>::Type U; \ + return Result(Name(~(U(a)))); \ + } + +#endif // mozilla_TypedEnumBits_h diff --git a/mfbt/Types.h b/mfbt/Types.h new file mode 100644 index 000000000..e7e18abb2 --- /dev/null +++ b/mfbt/Types.h @@ -0,0 +1,134 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* mfbt foundational types and macros. */ + +#ifndef mozilla_Types_h +#define mozilla_Types_h + +/* + * This header must be valid C and C++, includable by code embedding either + * SpiderMonkey or Gecko. + */ + +/* Expose all <stdint.h> types and size_t. */ +#include <stddef.h> +#include <stdint.h> + +/* Implement compiler and linker macros needed for APIs. */ + +/* + * MOZ_EXPORT is used to declare and define a symbol or type which is externally + * visible to users of the current library. It encapsulates various decorations + * needed to properly export the method's symbol. + * + * api.h: + * extern MOZ_EXPORT int MeaningOfLife(void); + * extern MOZ_EXPORT int LuggageCombination; + * + * api.c: + * int MeaningOfLife(void) { return 42; } + * int LuggageCombination = 12345; + * + * If you are merely sharing a method across files, just use plain |extern|. + * These macros are designed for use by library interfaces -- not for normal + * methods or data used cross-file. + */ +#if defined(WIN32) +# define MOZ_EXPORT __declspec(dllexport) +#else /* Unix */ +# ifdef HAVE_VISIBILITY_ATTRIBUTE +# define MOZ_EXPORT __attribute__((visibility("default"))) +# elif defined(__SUNPRO_C) || defined(__SUNPRO_CC) +# define MOZ_EXPORT __global +# else +# define MOZ_EXPORT /* nothing */ +# endif +#endif + + +/* + * Whereas implementers use MOZ_EXPORT to declare and define library symbols, + * users use MOZ_IMPORT_API and MOZ_IMPORT_DATA to access them. Most often the + * implementer of the library will expose an API macro which expands to either + * the export or import version of the macro, depending upon the compilation + * mode. + */ +#ifdef _WIN32 +# if defined(__MWERKS__) +# define MOZ_IMPORT_API /* nothing */ +# else +# define MOZ_IMPORT_API __declspec(dllimport) +# endif +#else +# define MOZ_IMPORT_API MOZ_EXPORT +#endif + +#if defined(_WIN32) && !defined(__MWERKS__) +# define MOZ_IMPORT_DATA __declspec(dllimport) +#else +# define MOZ_IMPORT_DATA MOZ_EXPORT +#endif + +/* + * Consistent with the above comment, the MFBT_API and MFBT_DATA macros expose + * export mfbt declarations when building mfbt, and they expose import mfbt + * declarations when using mfbt. + */ +#if defined(IMPL_MFBT) +# define MFBT_API MOZ_EXPORT +# define MFBT_DATA MOZ_EXPORT +#else + /* + * On linux mozglue is linked in the program and we link libxul.so with + * -z,defs. Normally that causes the linker to reject undefined references in + * libxul.so, but as a loophole it allows undefined references to weak + * symbols. We add the weak attribute to the import version of the MFBT API + * macros to exploit this. + */ +# if defined(MOZ_GLUE_IN_PROGRAM) +# define MFBT_API __attribute__((weak)) MOZ_IMPORT_API +# define MFBT_DATA __attribute__((weak)) MOZ_IMPORT_DATA +# else +# define MFBT_API MOZ_IMPORT_API +# define MFBT_DATA MOZ_IMPORT_DATA +# endif +#endif + +/* + * C symbols in C++ code must be declared immediately within |extern "C"| + * blocks. However, in C code, they need not be declared specially. This + * difference is abstracted behind the MOZ_BEGIN_EXTERN_C and MOZ_END_EXTERN_C + * macros, so that the user need not know whether he is being used in C or C++ + * code. + * + * MOZ_BEGIN_EXTERN_C + * + * extern MOZ_EXPORT int MostRandomNumber(void); + * ...other declarations... + * + * MOZ_END_EXTERN_C + * + * This said, it is preferable to just use |extern "C"| in C++ header files for + * its greater clarity. + */ +#ifdef __cplusplus +# define MOZ_BEGIN_EXTERN_C extern "C" { +# define MOZ_END_EXTERN_C } +#else +# define MOZ_BEGIN_EXTERN_C +# define MOZ_END_EXTERN_C +#endif + +/* + * GCC's typeof is available when decltype is not. + */ +#if defined(__GNUC__) && defined(__cplusplus) && \ + !defined(__GXX_EXPERIMENTAL_CXX0X__) && __cplusplus < 201103L +# define decltype __typeof__ +#endif + +#endif /* mozilla_Types_h */ diff --git a/mfbt/UniquePtr.h b/mfbt/UniquePtr.h new file mode 100644 index 000000000..7e1035bc6 --- /dev/null +++ b/mfbt/UniquePtr.h @@ -0,0 +1,697 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Smart pointer managing sole ownership of a resource. */ + +#ifndef mozilla_UniquePtr_h +#define mozilla_UniquePtr_h + +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" +#include "mozilla/Compiler.h" +#include "mozilla/Move.h" +#include "mozilla/Pair.h" +#include "mozilla/TypeTraits.h" + +namespace mozilla { + +template<typename T> class DefaultDelete; +template<typename T, class D = DefaultDelete<T>> class UniquePtr; + +} // namespace mozilla + +namespace mozilla { + +namespace detail { + +struct HasPointerTypeHelper +{ + template <class U> static double Test(...); + template <class U> static char Test(typename U::pointer* = 0); +}; + +template <class T> +class HasPointerType : public IntegralConstant<bool, sizeof(HasPointerTypeHelper::Test<T>(0)) == 1> +{ +}; + +template <class T, class D, bool = HasPointerType<D>::value> +struct PointerTypeImpl +{ + typedef typename D::pointer Type; +}; + +template <class T, class D> +struct PointerTypeImpl<T, D, false> +{ + typedef T* Type; +}; + +template <class T, class D> +struct PointerType +{ + typedef typename PointerTypeImpl<T, typename RemoveReference<D>::Type>::Type Type; +}; + +} // namespace detail + +/** + * UniquePtr is a smart pointer that wholly owns a resource. Ownership may be + * transferred out of a UniquePtr through explicit action, but otherwise the + * resource is destroyed when the UniquePtr is destroyed. + * + * UniquePtr is similar to C++98's std::auto_ptr, but it improves upon auto_ptr + * in one crucial way: it's impossible to copy a UniquePtr. Copying an auto_ptr + * obviously *can't* copy ownership of its singly-owned resource. So what + * happens if you try to copy one? Bizarrely, ownership is implicitly + * *transferred*, preserving single ownership but breaking code that assumes a + * copy of an object is identical to the original. (This is why auto_ptr is + * prohibited in STL containers.) + * + * UniquePtr solves this problem by being *movable* rather than copyable. + * Instead of passing a |UniquePtr u| directly to the constructor or assignment + * operator, you pass |Move(u)|. In doing so you indicate that you're *moving* + * ownership out of |u|, into the target of the construction/assignment. After + * the transfer completes, |u| contains |nullptr| and may be safely destroyed. + * This preserves single ownership but also allows UniquePtr to be moved by + * algorithms that have been made move-safe. (Note: if |u| is instead a + * temporary expression, don't use |Move()|: just pass the expression, because + * it's already move-ready. For more information see Move.h.) + * + * UniquePtr is also better than std::auto_ptr in that the deletion operation is + * customizable. An optional second template parameter specifies a class that + * (through its operator()(T*)) implements the desired deletion policy. If no + * policy is specified, mozilla::DefaultDelete<T> is used -- which will either + * |delete| or |delete[]| the resource, depending whether the resource is an + * array. Custom deletion policies ideally should be empty classes (no member + * fields, no member fields in base classes, no virtual methods/inheritance), + * because then UniquePtr can be just as efficient as a raw pointer. + * + * Use of UniquePtr proceeds like so: + * + * UniquePtr<int> g1; // initializes to nullptr + * g1.reset(new int); // switch resources using reset() + * g1 = nullptr; // clears g1, deletes the int + * + * UniquePtr<int> g2(new int); // owns that int + * int* p = g2.release(); // g2 leaks its int -- still requires deletion + * delete p; // now freed + * + * struct S { int x; S(int x) : x(x) {} }; + * UniquePtr<S> g3, g4(new S(5)); + * g3 = Move(g4); // g3 owns the S, g4 cleared + * S* p = g3.get(); // g3 still owns |p| + * assert(g3->x == 5); // operator-> works (if .get() != nullptr) + * assert((*g3).x == 5); // also operator* (again, if not cleared) + * Swap(g3, g4); // g4 now owns the S, g3 cleared + * g3.swap(g4); // g3 now owns the S, g4 cleared + * UniquePtr<S> g5(Move(g3)); // g5 owns the S, g3 cleared + * g5.reset(); // deletes the S, g5 cleared + * + * struct FreePolicy { void operator()(void* p) { free(p); } }; + * UniquePtr<int, FreePolicy> g6(static_cast<int*>(malloc(sizeof(int)))); + * int* ptr = g6.get(); + * g6 = nullptr; // calls free(ptr) + * + * Now, carefully note a few things you *can't* do: + * + * UniquePtr<int> b1; + * b1 = new int; // BAD: can only assign another UniquePtr + * int* ptr = b1; // BAD: no auto-conversion to pointer, use get() + * + * UniquePtr<int> b2(b1); // BAD: can't copy a UniquePtr + * UniquePtr<int> b3 = b1; // BAD: can't copy-assign a UniquePtr + * + * (Note that changing a UniquePtr to store a direct |new| expression is + * permitted, but usually you should use MakeUnique, defined at the end of this + * header.) + * + * A few miscellaneous notes: + * + * UniquePtr, when not instantiated for an array type, can be move-constructed + * and move-assigned, not only from itself but from "derived" UniquePtr<U, E> + * instantiations where U converts to T and E converts to D. If you want to use + * this, you're going to have to specify a deletion policy for both UniquePtr + * instantations, and T pretty much has to have a virtual destructor. In other + * words, this doesn't work: + * + * struct Base { virtual ~Base() {} }; + * struct Derived : Base {}; + * + * UniquePtr<Base> b1; + * // BAD: DefaultDelete<Base> and DefaultDelete<Derived> don't interconvert + * UniquePtr<Derived> d1(Move(b)); + * + * UniquePtr<Base> b2; + * UniquePtr<Derived, DefaultDelete<Base>> d2(Move(b2)); // okay + * + * UniquePtr is specialized for array types. Specializing with an array type + * creates a smart-pointer version of that array -- not a pointer to such an + * array. + * + * UniquePtr<int[]> arr(new int[5]); + * arr[0] = 4; + * + * What else is different? Deletion of course uses |delete[]|. An operator[] + * is provided. Functionality that doesn't make sense for arrays is removed. + * The constructors and mutating methods only accept array pointers (not T*, U* + * that converts to T*, or UniquePtr<U[]> or UniquePtr<U>) or |nullptr|. + * + * It's perfectly okay for a function to return a UniquePtr. This transfers + * the UniquePtr's sole ownership of the data, to the fresh UniquePtr created + * in the calling function, that will then solely own that data. Such functions + * can return a local variable UniquePtr, |nullptr|, |UniquePtr(ptr)| where + * |ptr| is a |T*|, or a UniquePtr |Move()|'d from elsewhere. + * + * UniquePtr will commonly be a member of a class, with lifetime equivalent to + * that of that class. If you want to expose the related resource, you could + * expose a raw pointer via |get()|, but ownership of a raw pointer is + * inherently unclear. So it's better to expose a |const UniquePtr&| instead. + * This prohibits mutation but still allows use of |get()| when needed (but + * operator-> is preferred). Of course, you can only use this smart pointer as + * long as the enclosing class instance remains live -- no different than if you + * exposed the |get()| raw pointer. + * + * To pass a UniquePtr-managed resource as a pointer, use a |const UniquePtr&| + * argument. To specify an inout parameter (where the method may or may not + * take ownership of the resource, or reset it), or to specify an out parameter + * (where simply returning a |UniquePtr| isn't possible), use a |UniquePtr&| + * argument. To unconditionally transfer ownership of a UniquePtr + * into a method, use a |UniquePtr| argument. To conditionally transfer + * ownership of a resource into a method, should the method want it, use a + * |UniquePtr&&| argument. + */ +template<typename T, class D> +class UniquePtr +{ +public: + typedef T ElementType; + typedef D DeleterType; + typedef typename detail::PointerType<T, DeleterType>::Type Pointer; + +private: + Pair<Pointer, DeleterType> mTuple; + + Pointer& ptr() { return mTuple.first(); } + const Pointer& ptr() const { return mTuple.first(); } + + DeleterType& del() { return mTuple.second(); } + const DeleterType& del() const { return mTuple.second(); } + +public: + /** + * Construct a UniquePtr containing |nullptr|. + */ + constexpr UniquePtr() + : mTuple(static_cast<Pointer>(nullptr), DeleterType()) + { + static_assert(!IsPointer<D>::value, "must provide a deleter instance"); + static_assert(!IsReference<D>::value, "must provide a deleter instance"); + } + + /** + * Construct a UniquePtr containing |aPtr|. + */ + explicit UniquePtr(Pointer aPtr) + : mTuple(aPtr, DeleterType()) + { + static_assert(!IsPointer<D>::value, "must provide a deleter instance"); + static_assert(!IsReference<D>::value, "must provide a deleter instance"); + } + + UniquePtr(Pointer aPtr, + typename Conditional<IsReference<D>::value, + D, + const D&>::Type aD1) + : mTuple(aPtr, aD1) + {} + + // If you encounter an error with MSVC10 about RemoveReference below, along + // the lines that "more than one partial specialization matches the template + // argument list": don't use UniquePtr<T, reference to function>! Ideally + // you should make deletion use the same function every time, using a + // deleter policy: + // + // // BAD, won't compile with MSVC10, deleter doesn't need to be a + // // variable at all + // typedef void (&FreeSignature)(void*); + // UniquePtr<int, FreeSignature> ptr((int*) malloc(sizeof(int)), free); + // + // // GOOD, compiles with MSVC10, deletion behavior statically known and + // // optimizable + // struct DeleteByFreeing + // { + // void operator()(void* aPtr) { free(aPtr); } + // }; + // + // If deletion really, truly, must be a variable: you might be able to work + // around this with a deleter class that contains the function reference. + // But this workaround is untried and untested, because variable deletion + // behavior really isn't something you should use. + UniquePtr(Pointer aPtr, + typename RemoveReference<D>::Type&& aD2) + : mTuple(aPtr, Move(aD2)) + { + static_assert(!IsReference<D>::value, + "rvalue deleter can't be stored by reference"); + } + + UniquePtr(UniquePtr&& aOther) + : mTuple(aOther.release(), Forward<DeleterType>(aOther.get_deleter())) + {} + + MOZ_IMPLICIT + UniquePtr(decltype(nullptr)) + : mTuple(nullptr, DeleterType()) + { + static_assert(!IsPointer<D>::value, "must provide a deleter instance"); + static_assert(!IsReference<D>::value, "must provide a deleter instance"); + } + + template<typename U, class E> + MOZ_IMPLICIT + UniquePtr(UniquePtr<U, E>&& aOther, + typename EnableIf<IsConvertible<typename UniquePtr<U, E>::Pointer, + Pointer>::value && + !IsArray<U>::value && + (IsReference<D>::value + ? IsSame<D, E>::value + : IsConvertible<E, D>::value), + int>::Type aDummy = 0) + : mTuple(aOther.release(), Forward<E>(aOther.get_deleter())) + { + } + + ~UniquePtr() { reset(nullptr); } + + UniquePtr& operator=(UniquePtr&& aOther) + { + reset(aOther.release()); + get_deleter() = Forward<DeleterType>(aOther.get_deleter()); + return *this; + } + + template<typename U, typename E> + UniquePtr& operator=(UniquePtr<U, E>&& aOther) + { + static_assert(IsConvertible<typename UniquePtr<U, E>::Pointer, + Pointer>::value, + "incompatible UniquePtr pointees"); + static_assert(!IsArray<U>::value, + "can't assign from UniquePtr holding an array"); + + reset(aOther.release()); + get_deleter() = Forward<E>(aOther.get_deleter()); + return *this; + } + + UniquePtr& operator=(decltype(nullptr)) + { + reset(nullptr); + return *this; + } + + T& operator*() const { return *get(); } + Pointer operator->() const + { + MOZ_ASSERT(get(), "dereferencing a UniquePtr containing nullptr"); + return get(); + } + + explicit operator bool() const { return get() != nullptr; } + + Pointer get() const { return ptr(); } + + DeleterType& get_deleter() { return del(); } + const DeleterType& get_deleter() const { return del(); } + + MOZ_MUST_USE Pointer release() + { + Pointer p = ptr(); + ptr() = nullptr; + return p; + } + + void reset(Pointer aPtr = Pointer()) + { + Pointer old = ptr(); + ptr() = aPtr; + if (old != nullptr) { + get_deleter()(old); + } + } + + void swap(UniquePtr& aOther) + { + mTuple.swap(aOther.mTuple); + } + + UniquePtr(const UniquePtr& aOther) = delete; // construct using Move()! + void operator=(const UniquePtr& aOther) = delete; // assign using Move()! +}; + +// In case you didn't read the comment by the main definition (you should!): the +// UniquePtr<T[]> specialization exists to manage array pointers. It deletes +// such pointers using delete[], it will reject construction and modification +// attempts using U* or U[]. Otherwise it works like the normal UniquePtr. +template<typename T, class D> +class UniquePtr<T[], D> +{ +public: + typedef T* Pointer; + typedef T ElementType; + typedef D DeleterType; + +private: + Pair<Pointer, DeleterType> mTuple; + +public: + /** + * Construct a UniquePtr containing nullptr. + */ + constexpr UniquePtr() + : mTuple(static_cast<Pointer>(nullptr), DeleterType()) + { + static_assert(!IsPointer<D>::value, "must provide a deleter instance"); + static_assert(!IsReference<D>::value, "must provide a deleter instance"); + } + + /** + * Construct a UniquePtr containing |aPtr|. + */ + explicit UniquePtr(Pointer aPtr) + : mTuple(aPtr, DeleterType()) + { + static_assert(!IsPointer<D>::value, "must provide a deleter instance"); + static_assert(!IsReference<D>::value, "must provide a deleter instance"); + } + + // delete[] knows how to handle *only* an array of a single class type. For + // delete[] to work correctly, it must know the size of each element, the + // fields and base classes of each element requiring destruction, and so on. + // So forbid all overloads which would end up invoking delete[] on a pointer + // of the wrong type. + template<typename U> + UniquePtr(U&& aU, + typename EnableIf<IsPointer<U>::value && + IsConvertible<U, Pointer>::value, + int>::Type aDummy = 0) + = delete; + + UniquePtr(Pointer aPtr, + typename Conditional<IsReference<D>::value, + D, + const D&>::Type aD1) + : mTuple(aPtr, aD1) + {} + + // If you encounter an error with MSVC10 about RemoveReference below, along + // the lines that "more than one partial specialization matches the template + // argument list": don't use UniquePtr<T[], reference to function>! See the + // comment by this constructor in the non-T[] specialization above. + UniquePtr(Pointer aPtr, + typename RemoveReference<D>::Type&& aD2) + : mTuple(aPtr, Move(aD2)) + { + static_assert(!IsReference<D>::value, + "rvalue deleter can't be stored by reference"); + } + + // Forbidden for the same reasons as stated above. + template<typename U, typename V> + UniquePtr(U&& aU, V&& aV, + typename EnableIf<IsPointer<U>::value && + IsConvertible<U, Pointer>::value, + int>::Type aDummy = 0) + = delete; + + UniquePtr(UniquePtr&& aOther) + : mTuple(aOther.release(), Forward<DeleterType>(aOther.get_deleter())) + {} + + MOZ_IMPLICIT + UniquePtr(decltype(nullptr)) + : mTuple(nullptr, DeleterType()) + { + static_assert(!IsPointer<D>::value, "must provide a deleter instance"); + static_assert(!IsReference<D>::value, "must provide a deleter instance"); + } + + ~UniquePtr() { reset(nullptr); } + + UniquePtr& operator=(UniquePtr&& aOther) + { + reset(aOther.release()); + get_deleter() = Forward<DeleterType>(aOther.get_deleter()); + return *this; + } + + UniquePtr& operator=(decltype(nullptr)) + { + reset(); + return *this; + } + + explicit operator bool() const { return get() != nullptr; } + + T& operator[](decltype(sizeof(int)) aIndex) const { return get()[aIndex]; } + Pointer get() const { return mTuple.first(); } + + DeleterType& get_deleter() { return mTuple.second(); } + const DeleterType& get_deleter() const { return mTuple.second(); } + + MOZ_MUST_USE Pointer release() + { + Pointer p = mTuple.first(); + mTuple.first() = nullptr; + return p; + } + + void reset(Pointer aPtr = Pointer()) + { + Pointer old = mTuple.first(); + mTuple.first() = aPtr; + if (old != nullptr) { + mTuple.second()(old); + } + } + + void reset(decltype(nullptr)) + { + Pointer old = mTuple.first(); + mTuple.first() = nullptr; + if (old != nullptr) { + mTuple.second()(old); + } + } + + template<typename U> + void reset(U) = delete; + + void swap(UniquePtr& aOther) { mTuple.swap(aOther.mTuple); } + + UniquePtr(const UniquePtr& aOther) = delete; // construct using Move()! + void operator=(const UniquePtr& aOther) = delete; // assign using Move()! +}; + +/** + * A default deletion policy using plain old operator delete. + * + * Note that this type can be specialized, but authors should beware of the risk + * that the specialization may at some point cease to match (either because it + * gets moved to a different compilation unit or the signature changes). If the + * non-specialized (|delete|-based) version compiles for that type but does the + * wrong thing, bad things could happen. + * + * This is a non-issue for types which are always incomplete (i.e. opaque handle + * types), since |delete|-ing such a type will always trigger a compilation + * error. + */ +template<typename T> +class DefaultDelete +{ +public: + constexpr DefaultDelete() {} + + template<typename U> + MOZ_IMPLICIT DefaultDelete(const DefaultDelete<U>& aOther, + typename EnableIf<mozilla::IsConvertible<U*, T*>::value, + int>::Type aDummy = 0) + {} + + void operator()(T* aPtr) const + { + static_assert(sizeof(T) > 0, "T must be complete"); + delete aPtr; + } +}; + +/** A default deletion policy using operator delete[]. */ +template<typename T> +class DefaultDelete<T[]> +{ +public: + constexpr DefaultDelete() {} + + void operator()(T* aPtr) const + { + static_assert(sizeof(T) > 0, "T must be complete"); + delete[] aPtr; + } + + template<typename U> + void operator()(U* aPtr) const = delete; +}; + +template<typename T, class D> +void +Swap(UniquePtr<T, D>& aX, UniquePtr<T, D>& aY) +{ + aX.swap(aY); +} + +template<typename T, class D, typename U, class E> +bool +operator==(const UniquePtr<T, D>& aX, const UniquePtr<U, E>& aY) +{ + return aX.get() == aY.get(); +} + +template<typename T, class D, typename U, class E> +bool +operator!=(const UniquePtr<T, D>& aX, const UniquePtr<U, E>& aY) +{ + return aX.get() != aY.get(); +} + +template<typename T, class D> +bool +operator==(const UniquePtr<T, D>& aX, decltype(nullptr)) +{ + return !aX; +} + +template<typename T, class D> +bool +operator==(decltype(nullptr), const UniquePtr<T, D>& aX) +{ + return !aX; +} + +template<typename T, class D> +bool +operator!=(const UniquePtr<T, D>& aX, decltype(nullptr)) +{ + return bool(aX); +} + +template<typename T, class D> +bool +operator!=(decltype(nullptr), const UniquePtr<T, D>& aX) +{ + return bool(aX); +} + +// No operator<, operator>, operator<=, operator>= for now because simplicity. + +namespace detail { + +template<typename T> +struct UniqueSelector +{ + typedef UniquePtr<T> SingleObject; +}; + +template<typename T> +struct UniqueSelector<T[]> +{ + typedef UniquePtr<T[]> UnknownBound; +}; + +template<typename T, decltype(sizeof(int)) N> +struct UniqueSelector<T[N]> +{ + typedef UniquePtr<T[N]> KnownBound; +}; + +} // namespace detail + +/** + * MakeUnique is a helper function for allocating new'd objects and arrays, + * returning a UniquePtr containing the resulting pointer. The semantics of + * MakeUnique<Type>(...) are as follows. + * + * If Type is an array T[n]: + * Disallowed, deleted, no overload for you! + * If Type is an array T[]: + * MakeUnique<T[]>(size_t) is the only valid overload. The pointer returned + * is as if by |new T[n]()|, which value-initializes each element. (If T + * isn't a class type, this will zero each element. If T is a class type, + * then roughly speaking, each element will be constructed using its default + * constructor. See C++11 [dcl.init]p7 for the full gory details.) + * If Type is non-array T: + * The arguments passed to MakeUnique<T>(...) are forwarded into a + * |new T(...)| call, initializing the T as would happen if executing + * |T(...)|. + * + * There are various benefits to using MakeUnique instead of |new| expressions. + * + * First, MakeUnique eliminates use of |new| from code entirely. If objects are + * only created through UniquePtr, then (assuming all explicit release() calls + * are safe, including transitively, and no type-safety casting funniness) + * correctly maintained ownership of the UniquePtr guarantees no leaks are + * possible. (This pays off best if a class is only ever created through a + * factory method on the class, using a private constructor.) + * + * Second, initializing a UniquePtr using a |new| expression requires repeating + * the name of the new'd type, whereas MakeUnique in concert with the |auto| + * keyword names it only once: + * + * UniquePtr<char> ptr1(new char()); // repetitive + * auto ptr2 = MakeUnique<char>(); // shorter + * + * Of course this assumes the reader understands the operation MakeUnique + * performs. In the long run this is probably a reasonable assumption. In the + * short run you'll have to use your judgment about what readers can be expected + * to know, or to quickly look up. + * + * Third, a call to MakeUnique can be assigned directly to a UniquePtr. In + * contrast you can't assign a pointer into a UniquePtr without using the + * cumbersome reset(). + * + * UniquePtr<char> p; + * p = new char; // ERROR + * p.reset(new char); // works, but fugly + * p = MakeUnique<char>(); // preferred + * + * (And third, although not relevant to Mozilla: MakeUnique is exception-safe. + * An exception thrown after |new T| succeeds will leak that memory, unless the + * pointer is assigned to an object that will manage its ownership. UniquePtr + * ably serves this function.) + */ + +template<typename T, typename... Args> +typename detail::UniqueSelector<T>::SingleObject +MakeUnique(Args&&... aArgs) +{ + return UniquePtr<T>(new T(Forward<Args>(aArgs)...)); +} + +template<typename T> +typename detail::UniqueSelector<T>::UnknownBound +MakeUnique(decltype(sizeof(int)) aN) +{ + typedef typename RemoveExtent<T>::Type ArrayType; + return UniquePtr<T>(new ArrayType[aN]()); +} + +template<typename T, typename... Args> +typename detail::UniqueSelector<T>::KnownBound +MakeUnique(Args&&... aArgs) = delete; + +} // namespace mozilla + +#endif /* mozilla_UniquePtr_h */ diff --git a/mfbt/UniquePtrExtensions.h b/mfbt/UniquePtrExtensions.h new file mode 100644 index 000000000..d94f33eea --- /dev/null +++ b/mfbt/UniquePtrExtensions.h @@ -0,0 +1,57 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Useful extensions to UniquePtr. */ + +#ifndef mozilla_UniquePtrExtensions_h +#define mozilla_UniquePtrExtensions_h + +#include "mozilla/fallible.h" +#include "mozilla/UniquePtr.h" + +namespace mozilla { + +/** + * MakeUniqueFallible works exactly like MakeUnique, except that the memory + * allocation performed is done fallibly, i.e. it can return nullptr. + */ +template<typename T, typename... Args> +typename detail::UniqueSelector<T>::SingleObject +MakeUniqueFallible(Args&&... aArgs) +{ + return UniquePtr<T>(new (fallible) T(Forward<Args>(aArgs)...)); +} + +template<typename T> +typename detail::UniqueSelector<T>::UnknownBound +MakeUniqueFallible(decltype(sizeof(int)) aN) +{ + typedef typename RemoveExtent<T>::Type ArrayType; + return UniquePtr<T>(new (fallible) ArrayType[aN]()); +} + +template<typename T, typename... Args> +typename detail::UniqueSelector<T>::KnownBound +MakeUniqueFallible(Args&&... aArgs) = delete; + +namespace detail { + +template<typename T> +struct FreePolicy +{ + void operator()(const void* ptr) { + free(const_cast<void*>(ptr)); + } +}; + +} // namespace detail + +template<typename T> +using UniqueFreePtr = UniquePtr<T, detail::FreePolicy<T>>; + +} // namespace mozilla + +#endif // mozilla_UniquePtrExtensions_h diff --git a/mfbt/Unused.cpp b/mfbt/Unused.cpp new file mode 100644 index 000000000..053a0c3d4 --- /dev/null +++ b/mfbt/Unused.cpp @@ -0,0 +1,13 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Unused.h" + +namespace mozilla { + +const unused_t Unused = unused_t(); + +} // namespace mozilla diff --git a/mfbt/Unused.h b/mfbt/Unused.h new file mode 100644 index 000000000..e693e32ac --- /dev/null +++ b/mfbt/Unused.h @@ -0,0 +1,38 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef mozilla_unused_h +#define mozilla_unused_h + +#include "mozilla/Types.h" + +#ifdef __cplusplus + +namespace mozilla { + +// +// Suppress GCC warnings about unused return values with +// Unused << SomeFuncDeclaredWarnUnusedReturnValue(); +// +struct unused_t +{ + template<typename T> + inline void + operator<<(const T& /*unused*/) const {} +}; + +extern MFBT_DATA const unused_t Unused; + +} // namespace mozilla + +#endif // __cplusplus + +// An alternative to mozilla::Unused for use in (a) C code and (b) code where +// linking with unused.o is difficult. +#define MOZ_UNUSED(expr) \ + do { if (expr) { (void)0; } } while (0) + +#endif // mozilla_unused_h diff --git a/mfbt/Variant.h b/mfbt/Variant.h new file mode 100644 index 000000000..8a33286ea --- /dev/null +++ b/mfbt/Variant.h @@ -0,0 +1,625 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* A template class for tagged unions. */ + +#include <new> +#include <stdint.h> + +#include "mozilla/Alignment.h" +#include "mozilla/Assertions.h" +#include "mozilla/Move.h" +#include "mozilla/TypeTraits.h" + +#ifndef mozilla_Variant_h +#define mozilla_Variant_h + +namespace mozilla { + +template<typename... Ts> +class Variant; + +namespace detail { + +// MaxSizeOf computes the maximum sizeof(T) for each T in Ts. + +template<typename T, typename... Ts> +struct MaxSizeOf +{ + static const size_t size = sizeof(T) > MaxSizeOf<Ts...>::size + ? sizeof(T) + : MaxSizeOf<Ts...>::size; +}; + +template<typename T> +struct MaxSizeOf<T> +{ + static const size_t size = sizeof(T); +}; + +// The `IsVariant` helper is used in conjunction with static_assert and +// `mozilla::EnableIf` to catch passing non-variant types to `Variant::is<T>()` +// and friends at compile time, rather than at runtime. It ensures that the +// given type `Needle` is one of the types in the set of types `Haystack`. + +template<typename Needle, typename... Haystack> +struct IsVariant; + +template<typename Needle> +struct IsVariant<Needle> +{ + static const bool value = false; +}; + +template<typename Needle, typename... Haystack> +struct IsVariant<Needle, Needle, Haystack...> +{ + static const bool value = true; +}; + +template<typename Needle, typename T, typename... Haystack> +struct IsVariant<Needle, T, Haystack...> : public IsVariant<Needle, Haystack...> { }; + +/// SelectVariantTypeHelper is used in the implementation of SelectVariantType. +template<typename T, typename... Variants> +struct SelectVariantTypeHelper; + +template<typename T> +struct SelectVariantTypeHelper<T> +{ }; + +template<typename T, typename... Variants> +struct SelectVariantTypeHelper<T, T, Variants...> +{ + typedef T Type; +}; + +template<typename T, typename... Variants> +struct SelectVariantTypeHelper<T, const T, Variants...> +{ + typedef const T Type; +}; + +template<typename T, typename... Variants> +struct SelectVariantTypeHelper<T, const T&, Variants...> +{ + typedef const T& Type; +}; + +template<typename T, typename... Variants> +struct SelectVariantTypeHelper<T, T&&, Variants...> +{ + typedef T&& Type; +}; + +template<typename T, typename Head, typename... Variants> +struct SelectVariantTypeHelper<T, Head, Variants...> + : public SelectVariantTypeHelper<T, Variants...> +{ }; + +/** + * SelectVariantType takes a type T and a list of variant types Variants and + * yields a type Type, selected from Variants, that can store a value of type T + * or a reference to type T. If no such type was found, Type is not defined. + */ +template <typename T, typename... Variants> +struct SelectVariantType + : public SelectVariantTypeHelper<typename RemoveConst<typename RemoveReference<T>::Type>::Type, + Variants...> +{ }; + +// Compute a fast, compact type that can be used to hold integral values that +// distinctly map to every type in Ts. +template<typename... Ts> +struct VariantTag +{ +private: + static const size_t TypeCount = sizeof...(Ts); + +public: + using Type = + typename Conditional<TypeCount < 3, + bool, + typename Conditional<TypeCount < (1 << 8), + uint_fast8_t, + size_t // stop caring past a certain point :-) + >::Type + >::Type; +}; + +// TagHelper gets the given sentinel tag value for the given type T. This has to +// be split out from VariantImplementation because you can't nest a partial +// template specialization within a template class. + +template<typename Tag, size_t N, typename T, typename U, typename Next, bool isMatch> +struct TagHelper; + +// In the case where T != U, we continue recursion. +template<typename Tag, size_t N, typename T, typename U, typename Next> +struct TagHelper<Tag, N, T, U, Next, false> +{ + static Tag tag() { return Next::template tag<U>(); } +}; + +// In the case where T == U, return the tag number. +template<typename Tag, size_t N, typename T, typename U, typename Next> +struct TagHelper<Tag, N, T, U, Next, true> +{ + static Tag tag() { return Tag(N); } +}; + +// The VariantImplementation template provides the guts of mozilla::Variant. We +// create a VariantImplementation for each T in Ts... which handles +// construction, destruction, etc for when the Variant's type is T. If the +// Variant's type isn't T, it punts the request on to the next +// VariantImplementation. + +template<typename Tag, size_t N, typename... Ts> +struct VariantImplementation; + +// The singly typed Variant / recursion base case. +template<typename Tag, size_t N, typename T> +struct VariantImplementation<Tag, N, T> +{ + template<typename U> + static Tag tag() { + static_assert(mozilla::IsSame<T, U>::value, + "mozilla::Variant: tag: bad type!"); + return Tag(N); + } + + template<typename Variant> + static void copyConstruct(void* aLhs, const Variant& aRhs) { + new (aLhs) T(aRhs.template as<T>()); + } + + template<typename Variant> + static void moveConstruct(void* aLhs, Variant&& aRhs) { + new (aLhs) T(aRhs.template extract<T>()); + } + + template<typename Variant> + static void destroy(Variant& aV) { + aV.template as<T>().~T(); + } + + template<typename Variant> + static bool + equal(const Variant& aLhs, const Variant& aRhs) { + return aLhs.template as<T>() == aRhs.template as<T>(); + } + + template<typename Matcher, typename ConcreteVariant> + static auto + match(Matcher&& aMatcher, ConcreteVariant& aV) + -> decltype(aMatcher.match(aV.template as<T>())) + { + return aMatcher.match(aV.template as<T>()); + } +}; + +// VariantImplementation for some variant type T. +template<typename Tag, size_t N, typename T, typename... Ts> +struct VariantImplementation<Tag, N, T, Ts...> +{ + // The next recursive VariantImplementation. + using Next = VariantImplementation<Tag, N + 1, Ts...>; + + template<typename U> + static Tag tag() { + return TagHelper<Tag, N, T, U, Next, IsSame<T, U>::value>::tag(); + } + + template<typename Variant> + static void copyConstruct(void* aLhs, const Variant& aRhs) { + if (aRhs.template is<T>()) { + new (aLhs) T(aRhs.template as<T>()); + } else { + Next::copyConstruct(aLhs, aRhs); + } + } + + template<typename Variant> + static void moveConstruct(void* aLhs, Variant&& aRhs) { + if (aRhs.template is<T>()) { + new (aLhs) T(aRhs.template extract<T>()); + } else { + Next::moveConstruct(aLhs, aRhs); + } + } + + template<typename Variant> + static void destroy(Variant& aV) { + if (aV.template is<T>()) { + aV.template as<T>().~T(); + } else { + Next::destroy(aV); + } + } + + template<typename Variant> + static bool equal(const Variant& aLhs, const Variant& aRhs) { + if (aLhs.template is<T>()) { + MOZ_ASSERT(aRhs.template is<T>()); + return aLhs.template as<T>() == aRhs.template as<T>(); + } else { + return Next::equal(aLhs, aRhs); + } + } + + template<typename Matcher, typename ConcreteVariant> + static auto + match(Matcher&& aMatcher, ConcreteVariant& aV) + -> decltype(aMatcher.match(aV.template as<T>())) + { + if (aV.template is<T>()) { + return aMatcher.match(aV.template as<T>()); + } else { + // If you're seeing compilation errors here like "no matching + // function for call to 'match'" then that means that the + // Matcher doesn't exhaust all variant types. There must exist a + // Matcher::match(T&) for every variant type T. + // + // If you're seeing compilation errors here like "cannot + // initialize return object of type <...> with an rvalue of type + // <...>" then that means that the Matcher::match(T&) overloads + // are returning different types. They must all return the same + // Matcher::ReturnType type. + return Next::match(aMatcher, aV); + } + } +}; + +/** + * AsVariantTemporary stores a value of type T to allow construction of a + * Variant value via type inference. Because T is copied and there's no + * guarantee that the copy can be elided, AsVariantTemporary is best used with + * primitive or very small types. + */ +template <typename T> +struct AsVariantTemporary +{ + explicit AsVariantTemporary(const T& aValue) + : mValue(aValue) + {} + + template<typename U> + explicit AsVariantTemporary(U&& aValue) + : mValue(Forward<U>(aValue)) + {} + + AsVariantTemporary(const AsVariantTemporary& aOther) + : mValue(aOther.mValue) + {} + + AsVariantTemporary(AsVariantTemporary&& aOther) + : mValue(Move(aOther.mValue)) + {} + + AsVariantTemporary() = delete; + void operator=(const AsVariantTemporary&) = delete; + void operator=(AsVariantTemporary&&) = delete; + + typename RemoveConst<typename RemoveReference<T>::Type>::Type mValue; +}; + +} // namespace detail + +/** + * # mozilla::Variant + * + * A variant / tagged union / heterogenous disjoint union / sum-type template + * class. Similar in concept to (but not derived from) `boost::variant`. + * + * Sometimes, you may wish to use a C union with non-POD types. However, this is + * forbidden in C++ because it is not clear which type in the union should have + * its constructor and destructor run on creation and deletion + * respectively. This is the problem that `mozilla::Variant` solves. + * + * ## Usage + * + * A `mozilla::Variant` instance is constructed (via move or copy) from one of + * its variant types (ignoring const and references). It does *not* support + * construction from subclasses of variant types or types that coerce to one of + * the variant types. + * + * Variant<char, uint32_t> v1('a'); + * Variant<UniquePtr<A>, B, C> v2(MakeUnique<A>()); + * + * Because specifying the full type of a Variant value is often verbose, + * AsVariant() can be used to construct a Variant value using type inference in + * contexts such as expressions or when returning values from functions. Because + * AsVariant() must copy or move the value into a temporary and this cannot + * necessarily be elided by the compiler, it's mostly appropriate only for use + * with primitive or very small types. + * + * + * Variant<char, uint32_t> Foo() { return AsVariant('x'); } + * // ... + * Variant<char, uint32_t> v1 = Foo(); // v1 holds char('x'). + * + * All access to the contained value goes through type-safe accessors. + * + * void + * Foo(Variant<A, B, C> v) + * { + * if (v.is<A>()) { + * A& ref = v.as<A>(); + * ... + * } else { + * ... + * } + * } + * + * Attempting to use the contained value as type `T1` when the `Variant` + * instance contains a value of type `T2` causes an assertion failure. + * + * A a; + * Variant<A, B, C> v(a); + * v.as<B>(); // <--- Assertion failure! + * + * Trying to use a `Variant<Ts...>` instance as some type `U` that is not a + * member of the set of `Ts...` is a compiler error. + * + * A a; + * Variant<A, B, C> v(a); + * v.as<SomeRandomType>(); // <--- Compiler error! + * + * Additionally, you can turn a `Variant` that `is<T>` into a `T` by moving it + * out of the containing `Variant` instance with the `extract<T>` method: + * + * Variant<UniquePtr<A>, B, C> v(MakeUnique<A>()); + * auto ptr = v.extract<UniquePtr<A>>(); + * + * Finally, you can exhaustively match on the contained variant and branch into + * different code paths depending which type is contained. This is preferred to + * manually checking every variant type T with is<T>() because it provides + * compile-time checking that you handled every type, rather than runtime + * assertion failures. + * + * // Bad! + * char* foo(Variant<A, B, C, D>& v) { + * if (v.is<A>()) { + * return ...; + * } else if (v.is<B>()) { + * return ...; + * } else { + * return doSomething(v.as<C>()); // Forgot about case D! + * } + * } + * + * // Good! + * struct FooMatcher + * { + * // The return type of all matchers must be identical. + * char* match(A& a) { ... } + * char* match(B& b) { ... } + * char* match(C& c) { ... } + * char* match(D& d) { ... } // Compile-time error to forget D! + * } + * char* foo(Variant<A, B, C, D>& v) { + * return v.match(FooMatcher()); + * } + * + * ## Examples + * + * A tree is either an empty leaf, or a node with a value and two children: + * + * struct Leaf { }; + * + * template<typename T> + * struct Node + * { + * T value; + * Tree<T>* left; + * Tree<T>* right; + * }; + * + * template<typename T> + * using Tree = Variant<Leaf, Node<T>>; + * + * A copy-on-write string is either a non-owning reference to some existing + * string, or an owning reference to our copy: + * + * class CopyOnWriteString + * { + * Variant<const char*, UniquePtr<char[]>> string; + * + * ... + * }; + */ +template<typename... Ts> +class MOZ_INHERIT_TYPE_ANNOTATIONS_FROM_TEMPLATE_ARGS Variant +{ + using Tag = typename detail::VariantTag<Ts...>::Type; + using Impl = detail::VariantImplementation<Tag, 0, Ts...>; + using RawData = AlignedStorage<detail::MaxSizeOf<Ts...>::size>; + + // Raw storage for the contained variant value. + RawData raw; + + // Each type is given a unique tag value that lets us keep track of the + // contained variant value's type. + Tag tag; + + void* ptr() { + return reinterpret_cast<void*>(&raw); + } + +public: + /** Perfect forwarding construction for some variant type T. */ + template<typename RefT, + // RefT captures both const& as well as && (as intended, to support + // perfect forwarding), so we have to remove those qualifiers here + // when ensuring that T is a variant of this type, and getting T's + // tag, etc. + typename T = typename detail::SelectVariantType<RefT, Ts...>::Type> + explicit Variant(RefT&& aT) + : tag(Impl::template tag<T>()) + { + new (ptr()) T(Forward<RefT>(aT)); + } + + /** + * Constructs this Variant from an AsVariantTemporary<T> such that T can be + * stored in one of the types allowable in this Variant. This is used in the + * implementation of AsVariant(). + */ + template<typename RefT, + typename T = typename detail::SelectVariantType<RefT, Ts...>::Type> + MOZ_IMPLICIT Variant(detail::AsVariantTemporary<RefT>&& aValue) + : tag(Impl::template tag<T>()) + { + new (ptr()) T(Move(aValue.mValue)); + } + + /** Copy construction. */ + Variant(const Variant& aRhs) + : tag(aRhs.tag) + { + Impl::copyConstruct(ptr(), aRhs); + } + + /** Move construction. */ + Variant(Variant&& aRhs) + : tag(aRhs.tag) + { + Impl::moveConstruct(ptr(), Move(aRhs)); + } + + /** Copy assignment. */ + Variant& operator=(const Variant& aRhs) { + MOZ_ASSERT(&aRhs != this, "self-assign disallowed"); + this->~Variant(); + new (this) Variant(aRhs); + return *this; + } + + /** Move assignment. */ + Variant& operator=(Variant&& aRhs) { + MOZ_ASSERT(&aRhs != this, "self-assign disallowed"); + this->~Variant(); + new (this) Variant(Move(aRhs)); + return *this; + } + + /** Move assignment from AsVariant(). */ + template <typename T> + Variant& operator=(detail::AsVariantTemporary<T>&& aValue) + { + this->~Variant(); + new (this) Variant(Move(aValue)); + return *this; + } + + ~Variant() + { + Impl::destroy(*this); + } + + /** Check which variant type is currently contained. */ + template<typename T> + bool is() const { + static_assert(detail::IsVariant<T, Ts...>::value, + "provided a type not found in this Variant's type list"); + return Impl::template tag<T>() == tag; + } + + /** + * Operator == overload that defers to the variant type's operator== + * implementation if the rhs is tagged as the same type as this one. + */ + bool operator==(const Variant& aRhs) const { + return tag == aRhs.tag && Impl::equal(*this, aRhs); + } + + /** + * Operator != overload that defers to the negation of the variant type's + * operator== implementation if the rhs is tagged as the same type as this + * one. + */ + bool operator!=(const Variant& aRhs) const { + return !(*this == aRhs); + } + + // Accessors for working with the contained variant value. + + /** Mutable reference. */ + template<typename T> + T& as() { + static_assert(detail::IsVariant<T, Ts...>::value, + "provided a type not found in this Variant's type list"); + MOZ_ASSERT(is<T>()); + return *reinterpret_cast<T*>(&raw); + } + + /** Immutable const reference. */ + template<typename T> + const T& as() const { + static_assert(detail::IsVariant<T, Ts...>::value, + "provided a type not found in this Variant's type list"); + MOZ_ASSERT(is<T>()); + return *reinterpret_cast<const T*>(&raw); + } + + /** + * Extract the contained variant value from this container into a temporary + * value. On completion, the value in the variant will be in a + * safely-destructible state, as determined by the behavior of T's move + * constructor when provided the variant's internal value. + */ + template<typename T> + T extract() { + static_assert(detail::IsVariant<T, Ts...>::value, + "provided a type not found in this Variant's type list"); + MOZ_ASSERT(is<T>()); + return T(Move(as<T>())); + } + + // Exhaustive matching of all variant types on the contained value. + + /** Match on an immutable const reference. */ + template<typename Matcher> + auto + match(Matcher&& aMatcher) const + -> decltype(Impl::match(aMatcher, *this)) + { + return Impl::match(aMatcher, *this); + } + + /** Match on a mutable non-const reference. */ + template<typename Matcher> + auto + match(Matcher&& aMatcher) + -> decltype(Impl::match(aMatcher, *this)) + { + return Impl::match(aMatcher, *this); + } +}; + +/* + * AsVariant() is used to construct a Variant<T,...> value containing the + * provided T value using type inference. It can be used to construct Variant + * values in expressions or return them from functions without specifying the + * entire Variant type. + * + * Because AsVariant() must copy or move the value into a temporary and this + * cannot necessarily be elided by the compiler, it's mostly appropriate only + * for use with primitive or very small types. + * + * AsVariant() returns a AsVariantTemporary value which is implicitly + * convertible to any Variant that can hold a value of type T. + */ +template<typename T> +detail::AsVariantTemporary<T> +AsVariant(T&& aValue) +{ + return detail::AsVariantTemporary<T>(Forward<T>(aValue)); +} + +} // namespace mozilla + +#endif /* mozilla_Variant_h */ diff --git a/mfbt/Vector.h b/mfbt/Vector.h new file mode 100644 index 000000000..fc43afcf1 --- /dev/null +++ b/mfbt/Vector.h @@ -0,0 +1,1491 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* A type/length-parametrized vector class. */ + +#ifndef mozilla_Vector_h +#define mozilla_Vector_h + +#include "mozilla/Alignment.h" +#include "mozilla/AllocPolicy.h" +#include "mozilla/ArrayUtils.h" // for PointerRangeSize +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" +#include "mozilla/MathAlgorithms.h" +#include "mozilla/MemoryReporting.h" +#include "mozilla/Move.h" +#include "mozilla/OperatorNewExtensions.h" +#include "mozilla/ReentrancyGuard.h" +#include "mozilla/TemplateLib.h" +#include "mozilla/TypeTraits.h" + +#include <new> // for placement new + +/* Silence dire "bugs in previous versions of MSVC have been fixed" warnings */ +#ifdef _MSC_VER +#pragma warning(push) +#pragma warning(disable:4345) +#endif + +namespace mozilla { + +template<typename T, size_t N, class AllocPolicy> +class Vector; + +namespace detail { + +/* + * Check that the given capacity wastes the minimal amount of space if + * allocated on the heap. This means that aCapacity*sizeof(T) is as close to a + * power-of-two as possible. growStorageBy() is responsible for ensuring this. + */ +template<typename T> +static bool CapacityHasExcessSpace(size_t aCapacity) +{ + size_t size = aCapacity * sizeof(T); + return RoundUpPow2(size) - size >= sizeof(T); +} + +/* + * This template class provides a default implementation for vector operations + * when the element type is not known to be a POD, as judged by IsPod. + */ +template<typename T, size_t N, class AP, bool IsPod> +struct VectorImpl +{ + /* + * Constructs an object in the uninitialized memory at *aDst with aArgs. + */ + template<typename... Args> + MOZ_NONNULL(1) + static inline void new_(T* aDst, Args&&... aArgs) + { + new(KnownNotNull, aDst) T(Forward<Args>(aArgs)...); + } + + /* Destroys constructed objects in the range [aBegin, aEnd). */ + static inline void destroy(T* aBegin, T* aEnd) + { + MOZ_ASSERT(aBegin <= aEnd); + for (T* p = aBegin; p < aEnd; ++p) { + p->~T(); + } + } + + /* Constructs objects in the uninitialized range [aBegin, aEnd). */ + static inline void initialize(T* aBegin, T* aEnd) + { + MOZ_ASSERT(aBegin <= aEnd); + for (T* p = aBegin; p < aEnd; ++p) { + new_(p); + } + } + + /* + * Copy-constructs objects in the uninitialized range + * [aDst, aDst+(aSrcEnd-aSrcStart)) from the range [aSrcStart, aSrcEnd). + */ + template<typename U> + static inline void copyConstruct(T* aDst, + const U* aSrcStart, const U* aSrcEnd) + { + MOZ_ASSERT(aSrcStart <= aSrcEnd); + for (const U* p = aSrcStart; p < aSrcEnd; ++p, ++aDst) { + new_(aDst, *p); + } + } + + /* + * Move-constructs objects in the uninitialized range + * [aDst, aDst+(aSrcEnd-aSrcStart)) from the range [aSrcStart, aSrcEnd). + */ + template<typename U> + static inline void moveConstruct(T* aDst, U* aSrcStart, U* aSrcEnd) + { + MOZ_ASSERT(aSrcStart <= aSrcEnd); + for (U* p = aSrcStart; p < aSrcEnd; ++p, ++aDst) { + new_(aDst, Move(*p)); + } + } + + /* + * Copy-constructs objects in the uninitialized range [aDst, aDst+aN) from + * the same object aU. + */ + template<typename U> + static inline void copyConstructN(T* aDst, size_t aN, const U& aU) + { + for (T* end = aDst + aN; aDst < end; ++aDst) { + new_(aDst, aU); + } + } + + /* + * Grows the given buffer to have capacity aNewCap, preserving the objects + * constructed in the range [begin, end) and updating aV. Assumes that (1) + * aNewCap has not overflowed, and (2) multiplying aNewCap by sizeof(T) will + * not overflow. + */ + static inline MOZ_MUST_USE bool + growTo(Vector<T, N, AP>& aV, size_t aNewCap) + { + MOZ_ASSERT(!aV.usingInlineStorage()); + MOZ_ASSERT(!CapacityHasExcessSpace<T>(aNewCap)); + T* newbuf = aV.template pod_malloc<T>(aNewCap); + if (MOZ_UNLIKELY(!newbuf)) { + return false; + } + T* dst = newbuf; + T* src = aV.beginNoCheck(); + for (; src < aV.endNoCheck(); ++dst, ++src) { + new_(dst, Move(*src)); + } + VectorImpl::destroy(aV.beginNoCheck(), aV.endNoCheck()); + aV.free_(aV.mBegin); + aV.mBegin = newbuf; + /* aV.mLength is unchanged. */ + aV.mCapacity = aNewCap; + return true; + } +}; + +/* + * This partial template specialization provides a default implementation for + * vector operations when the element type is known to be a POD, as judged by + * IsPod. + */ +template<typename T, size_t N, class AP> +struct VectorImpl<T, N, AP, true> +{ + template<typename... Args> + MOZ_NONNULL(1) + static inline void new_(T* aDst, Args&&... aArgs) + { + // Explicitly construct a local object instead of using a temporary since + // T(args...) will be treated like a C-style cast in the unary case and + // allow unsafe conversions. Both forms should be equivalent to an + // optimizing compiler. + T temp(Forward<Args>(aArgs)...); + *aDst = temp; + } + + static inline void destroy(T*, T*) {} + + static inline void initialize(T* aBegin, T* aEnd) + { + /* + * You would think that memset would be a big win (or even break even) + * when we know T is a POD. But currently it's not. This is probably + * because |append| tends to be given small ranges and memset requires + * a function call that doesn't get inlined. + * + * memset(aBegin, 0, sizeof(T) * (aEnd - aBegin)); + */ + MOZ_ASSERT(aBegin <= aEnd); + for (T* p = aBegin; p < aEnd; ++p) { + new_(p); + } + } + + template<typename U> + static inline void copyConstruct(T* aDst, + const U* aSrcStart, const U* aSrcEnd) + { + /* + * See above memset comment. Also, notice that copyConstruct is + * currently templated (T != U), so memcpy won't work without + * requiring T == U. + * + * memcpy(aDst, aSrcStart, sizeof(T) * (aSrcEnd - aSrcStart)); + */ + MOZ_ASSERT(aSrcStart <= aSrcEnd); + for (const U* p = aSrcStart; p < aSrcEnd; ++p, ++aDst) { + new_(aDst, *p); + } + } + + template<typename U> + static inline void moveConstruct(T* aDst, + const U* aSrcStart, const U* aSrcEnd) + { + copyConstruct(aDst, aSrcStart, aSrcEnd); + } + + static inline void copyConstructN(T* aDst, size_t aN, const T& aT) + { + for (T* end = aDst + aN; aDst < end; ++aDst) { + new_(aDst, aT); + } + } + + static inline MOZ_MUST_USE bool + growTo(Vector<T, N, AP>& aV, size_t aNewCap) + { + MOZ_ASSERT(!aV.usingInlineStorage()); + MOZ_ASSERT(!CapacityHasExcessSpace<T>(aNewCap)); + T* newbuf = aV.template pod_realloc<T>(aV.mBegin, aV.mCapacity, aNewCap); + if (MOZ_UNLIKELY(!newbuf)) { + return false; + } + aV.mBegin = newbuf; + /* aV.mLength is unchanged. */ + aV.mCapacity = aNewCap; + return true; + } + + static inline void + podResizeToFit(Vector<T, N, AP>& aV) + { + if (aV.usingInlineStorage() || aV.mLength == aV.mCapacity) { + return; + } + T* newbuf = aV.template pod_realloc<T>(aV.mBegin, aV.mCapacity, aV.mLength); + if (MOZ_UNLIKELY(!newbuf)) { + return; + } + aV.mBegin = newbuf; + aV.mCapacity = aV.mLength; + } +}; + +// A struct for TestVector.cpp to access private internal fields. +// DO NOT DEFINE IN YOUR OWN CODE. +struct VectorTesting; + +} // namespace detail + +/* + * STL-like container providing a short-lived, dynamic buffer. Vector calls the + * constructors/destructors of all elements stored in its internal buffer, so + * non-PODs may be safely used. Additionally, Vector will store the first N + * elements in-place before resorting to dynamic allocation. + * + * T requirements: + * - default and copy constructible, assignable, destructible + * - operations do not throw + * MinInlineCapacity requirements: + * - any value, however, MinInlineCapacity is clamped to min/max values + * AllocPolicy: + * - see "Allocation policies" in AllocPolicy.h (defaults to + * mozilla::MallocAllocPolicy) + * + * Vector is not reentrant: T member functions called during Vector member + * functions must not call back into the same object! + */ +template<typename T, + size_t MinInlineCapacity = 0, + class AllocPolicy = MallocAllocPolicy> +class Vector final : private AllocPolicy +{ + /* utilities */ + + static const bool kElemIsPod = IsPod<T>::value; + typedef detail::VectorImpl<T, MinInlineCapacity, AllocPolicy, kElemIsPod> Impl; + friend struct detail::VectorImpl<T, MinInlineCapacity, AllocPolicy, kElemIsPod>; + + friend struct detail::VectorTesting; + + MOZ_MUST_USE bool growStorageBy(size_t aIncr); + MOZ_MUST_USE bool convertToHeapStorage(size_t aNewCap); + MOZ_MUST_USE bool maybeCheckSimulatedOOM(size_t aRequestedSize); + + /* magic constants */ + + static const int kMaxInlineBytes = 1024; + + /* compute constants */ + + /* + * Consider element size to be 1 for buffer sizing if there are 0 inline + * elements. This allows us to compile when the definition of the element + * type is not visible here. + * + * Explicit specialization is only allowed at namespace scope, so in order + * to keep everything here, we use a dummy template parameter with partial + * specialization. + */ + template<int M, int Dummy> + struct ElemSize + { + static const size_t value = sizeof(T); + }; + template<int Dummy> + struct ElemSize<0, Dummy> + { + static const size_t value = 1; + }; + + static const size_t kInlineCapacity = + tl::Min<MinInlineCapacity, kMaxInlineBytes / ElemSize<MinInlineCapacity, 0>::value>::value; + + /* Calculate inline buffer size; avoid 0-sized array. */ + static const size_t kInlineBytes = + tl::Max<1, kInlineCapacity * ElemSize<MinInlineCapacity, 0>::value>::value; + + /* member data */ + + /* + * Pointer to the buffer, be it inline or heap-allocated. Only [mBegin, + * mBegin + mLength) hold valid constructed T objects. The range [mBegin + + * mLength, mBegin + mCapacity) holds uninitialized memory. The range + * [mBegin + mLength, mBegin + mReserved) also holds uninitialized memory + * previously allocated by a call to reserve(). + */ + T* mBegin; + + /* Number of elements in the vector. */ + size_t mLength; + + /* Max number of elements storable in the vector without resizing. */ + size_t mCapacity; + +#ifdef DEBUG + /* Max elements of reserved or used space in this vector. */ + size_t mReserved; +#endif + + /* Memory used for inline storage. */ + AlignedStorage<kInlineBytes> mStorage; + +#ifdef DEBUG + friend class ReentrancyGuard; + bool mEntered; +#endif + + /* private accessors */ + + bool usingInlineStorage() const + { + return mBegin == const_cast<Vector*>(this)->inlineStorage(); + } + + T* inlineStorage() + { + return static_cast<T*>(mStorage.addr()); + } + + T* beginNoCheck() const + { + return mBegin; + } + + T* endNoCheck() + { + return mBegin + mLength; + } + + const T* endNoCheck() const + { + return mBegin + mLength; + } + +#ifdef DEBUG + /** + * The amount of explicitly allocated space in this vector that is immediately + * available to be filled by appending additional elements. This value is + * always greater than or equal to |length()| -- the vector's actual elements + * are implicitly reserved. This value is always less than or equal to + * |capacity()|. It may be explicitly increased using the |reserve()| method. + */ + size_t reserved() const + { + MOZ_ASSERT(mLength <= mReserved); + MOZ_ASSERT(mReserved <= mCapacity); + return mReserved; + } +#endif + + /* Append operations guaranteed to succeed due to pre-reserved space. */ + template<typename U> void internalAppend(U&& aU); + template<typename U, size_t O, class BP> + void internalAppendAll(const Vector<U, O, BP>& aU); + void internalAppendN(const T& aT, size_t aN); + template<typename U> void internalAppend(const U* aBegin, size_t aLength); + +public: + static const size_t sMaxInlineStorage = MinInlineCapacity; + + typedef T ElementType; + + explicit Vector(AllocPolicy = AllocPolicy()); + Vector(Vector&&); /* Move constructor. */ + Vector& operator=(Vector&&); /* Move assignment. */ + ~Vector(); + + /* accessors */ + + const AllocPolicy& allocPolicy() const { return *this; } + + AllocPolicy& allocPolicy() { return *this; } + + enum { InlineLength = MinInlineCapacity }; + + size_t length() const { return mLength; } + + bool empty() const { return mLength == 0; } + + size_t capacity() const { return mCapacity; } + + T* begin() + { + MOZ_ASSERT(!mEntered); + return mBegin; + } + + const T* begin() const + { + MOZ_ASSERT(!mEntered); + return mBegin; + } + + T* end() + { + MOZ_ASSERT(!mEntered); + return mBegin + mLength; + } + + const T* end() const + { + MOZ_ASSERT(!mEntered); + return mBegin + mLength; + } + + T& operator[](size_t aIndex) + { + MOZ_ASSERT(!mEntered); + MOZ_ASSERT(aIndex < mLength); + return begin()[aIndex]; + } + + const T& operator[](size_t aIndex) const + { + MOZ_ASSERT(!mEntered); + MOZ_ASSERT(aIndex < mLength); + return begin()[aIndex]; + } + + T& back() + { + MOZ_ASSERT(!mEntered); + MOZ_ASSERT(!empty()); + return *(end() - 1); + } + + const T& back() const + { + MOZ_ASSERT(!mEntered); + MOZ_ASSERT(!empty()); + return *(end() - 1); + } + + class Range + { + friend class Vector; + T* mCur; + T* mEnd; + Range(T* aCur, T* aEnd) + : mCur(aCur) + , mEnd(aEnd) + { + MOZ_ASSERT(aCur <= aEnd); + } + + public: + bool empty() const { return mCur == mEnd; } + size_t remain() const { return PointerRangeSize(mCur, mEnd); } + T& front() const { MOZ_ASSERT(!empty()); return *mCur; } + void popFront() { MOZ_ASSERT(!empty()); ++mCur; } + T popCopyFront() { MOZ_ASSERT(!empty()); return *mCur++; } + }; + + class ConstRange + { + friend class Vector; + const T* mCur; + const T* mEnd; + ConstRange(const T* aCur, const T* aEnd) + : mCur(aCur) + , mEnd(aEnd) + { + MOZ_ASSERT(aCur <= aEnd); + } + + public: + bool empty() const { return mCur == mEnd; } + size_t remain() const { return PointerRangeSize(mCur, mEnd); } + const T& front() const { MOZ_ASSERT(!empty()); return *mCur; } + void popFront() { MOZ_ASSERT(!empty()); ++mCur; } + T popCopyFront() { MOZ_ASSERT(!empty()); return *mCur++; } + }; + + Range all() { return Range(begin(), end()); } + ConstRange all() const { return ConstRange(begin(), end()); } + + /* mutators */ + + /** + * Reverse the order of the elements in the vector in place. + */ + void reverse(); + + /** + * Given that the vector is empty, grow the internal capacity to |aRequest|, + * keeping the length 0. + */ + MOZ_MUST_USE bool initCapacity(size_t aRequest); + + /** + * Given that the vector is empty, grow the internal capacity and length to + * |aRequest| leaving the elements' memory completely uninitialized (with all + * the associated hazards and caveats). This avoids the usual allocation-size + * rounding that happens in resize and overhead of initialization for elements + * that are about to be overwritten. + */ + MOZ_MUST_USE bool initLengthUninitialized(size_t aRequest); + + /** + * If reserve(aRequest) succeeds and |aRequest >= length()|, then appending + * |aRequest - length()| elements, in any sequence of append/appendAll calls, + * is guaranteed to succeed. + * + * A request to reserve an amount less than the current length does not affect + * reserved space. + */ + MOZ_MUST_USE bool reserve(size_t aRequest); + + /** + * Destroy elements in the range [end() - aIncr, end()). Does not deallocate + * or unreserve storage for those elements. + */ + void shrinkBy(size_t aIncr); + + /** + * Destroy elements in the range [aNewLength, end()). Does not deallocate + * or unreserve storage for those elements. + */ + void shrinkTo(size_t aNewLength); + + /** Grow the vector by aIncr elements. */ + MOZ_MUST_USE bool growBy(size_t aIncr); + + /** Call shrinkBy or growBy based on whether newSize > length(). */ + MOZ_MUST_USE bool resize(size_t aNewLength); + + /** + * Increase the length of the vector, but don't initialize the new elements + * -- leave them as uninitialized memory. + */ + MOZ_MUST_USE bool growByUninitialized(size_t aIncr); + void infallibleGrowByUninitialized(size_t aIncr); + MOZ_MUST_USE bool resizeUninitialized(size_t aNewLength); + + /** Shorthand for shrinkBy(length()). */ + void clear(); + + /** Clears and releases any heap-allocated storage. */ + void clearAndFree(); + + /** + * Calls the AllocPolicy's pod_realloc to release excess capacity. Since + * realloc is only safe on PODs, this method fails to compile if IsPod<T> + * is false. + */ + void podResizeToFit(); + + /** + * If true, appending |aNeeded| elements won't reallocate elements storage. + * This *doesn't* mean that infallibleAppend may be used! You still must + * reserve the extra space, even if this method indicates that appends won't + * need to reallocate elements storage. + */ + bool canAppendWithoutRealloc(size_t aNeeded) const; + + /** Potentially fallible append operations. */ + + /** + * This can take either a T& or a T&&. Given a T&&, it moves |aU| into the + * vector, instead of copying it. If it fails, |aU| is left unmoved. ("We are + * not amused.") + */ + template<typename U> MOZ_MUST_USE bool append(U&& aU); + + /** + * Construct a T in-place as a new entry at the end of this vector. + */ + template<typename... Args> + MOZ_MUST_USE bool emplaceBack(Args&&... aArgs) + { + if (!growByUninitialized(1)) + return false; + Impl::new_(&back(), Forward<Args>(aArgs)...); + return true; + } + + template<typename U, size_t O, class BP> + MOZ_MUST_USE bool appendAll(const Vector<U, O, BP>& aU); + MOZ_MUST_USE bool appendN(const T& aT, size_t aN); + template<typename U> MOZ_MUST_USE bool append(const U* aBegin, const U* aEnd); + template<typename U> MOZ_MUST_USE bool append(const U* aBegin, size_t aLength); + + /* + * Guaranteed-infallible append operations for use upon vectors whose + * memory has been pre-reserved. Don't use this if you haven't reserved the + * memory! + */ + template<typename U> void infallibleAppend(U&& aU) + { + internalAppend(Forward<U>(aU)); + } + void infallibleAppendN(const T& aT, size_t aN) + { + internalAppendN(aT, aN); + } + template<typename U> void infallibleAppend(const U* aBegin, const U* aEnd) + { + internalAppend(aBegin, PointerRangeSize(aBegin, aEnd)); + } + template<typename U> void infallibleAppend(const U* aBegin, size_t aLength) + { + internalAppend(aBegin, aLength); + } + template<typename... Args> + void infallibleEmplaceBack(Args&&... aArgs) + { + infallibleGrowByUninitialized(1); + Impl::new_(&back(), Forward<Args>(aArgs)...); + } + + void popBack(); + + T popCopy(); + + /** + * If elements are stored in-place, return nullptr and leave this vector + * unmodified. + * + * Otherwise return this vector's elements buffer, and clear this vector as if + * by clearAndFree(). The caller now owns the buffer and is responsible for + * deallocating it consistent with this vector's AllocPolicy. + * + * N.B. Although a T*, only the range [0, length()) is constructed. + */ + MOZ_MUST_USE T* extractRawBuffer(); + + /** + * If elements are stored in-place, allocate a new buffer, move this vector's + * elements into it, and return that buffer. + * + * Otherwise return this vector's elements buffer. The caller now owns the + * buffer and is responsible for deallocating it consistent with this vector's + * AllocPolicy. + * + * This vector is cleared, as if by clearAndFree(), when this method + * succeeds. This method fails and returns nullptr only if new elements buffer + * allocation fails. + * + * N.B. Only the range [0, length()) of the returned buffer is constructed. + * If any of these elements are uninitialized (as growByUninitialized + * enables), behavior is undefined. + */ + MOZ_MUST_USE T* extractOrCopyRawBuffer(); + + /** + * Transfer ownership of an array of objects into the vector. The caller + * must have allocated the array in accordance with this vector's + * AllocPolicy. + * + * N.B. This call assumes that there are no uninitialized elements in the + * passed array. + */ + void replaceRawBuffer(T* aP, size_t aLength); + + /** + * Places |aVal| at position |aP|, shifting existing elements from |aP| onward + * one position higher. On success, |aP| should not be reused because it'll + * be a dangling pointer if reallocation of the vector storage occurred; the + * return value should be used instead. On failure, nullptr is returned. + * + * Example usage: + * + * if (!(p = vec.insert(p, val))) { + * <handle failure> + * } + * <keep working with p> + * + * This is inherently a linear-time operation. Be careful! + */ + template<typename U> + MOZ_MUST_USE T* insert(T* aP, U&& aVal); + + /** + * Removes the element |aT|, which must fall in the bounds [begin, end), + * shifting existing elements from |aT + 1| onward one position lower. + */ + void erase(T* aT); + + /** + * Removes the elements [|aBegin|, |aEnd|), which must fall in the bounds + * [begin, end), shifting existing elements from |aEnd + 1| onward to aBegin's + * old position. + */ + void erase(T* aBegin, T* aEnd); + + /** + * Measure the size of the vector's heap-allocated storage. + */ + size_t sizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const; + + /** + * Like sizeOfExcludingThis, but also measures the size of the vector + * object (which must be heap-allocated) itself. + */ + size_t sizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const; + + void swap(Vector& aOther); + +private: + Vector(const Vector&) = delete; + void operator=(const Vector&) = delete; +}; + +/* This does the re-entrancy check plus several other sanity checks. */ +#define MOZ_REENTRANCY_GUARD_ET_AL \ + ReentrancyGuard g(*this); \ + MOZ_ASSERT_IF(usingInlineStorage(), mCapacity == kInlineCapacity); \ + MOZ_ASSERT(reserved() <= mCapacity); \ + MOZ_ASSERT(mLength <= reserved()); \ + MOZ_ASSERT(mLength <= mCapacity) + +/* Vector Implementation */ + +template<typename T, size_t N, class AP> +MOZ_ALWAYS_INLINE +Vector<T, N, AP>::Vector(AP aAP) + : AP(aAP) + , mLength(0) + , mCapacity(kInlineCapacity) +#ifdef DEBUG + , mReserved(0) + , mEntered(false) +#endif +{ + mBegin = static_cast<T*>(mStorage.addr()); +} + +/* Move constructor. */ +template<typename T, size_t N, class AllocPolicy> +MOZ_ALWAYS_INLINE +Vector<T, N, AllocPolicy>::Vector(Vector&& aRhs) + : AllocPolicy(Move(aRhs)) +#ifdef DEBUG + , mEntered(false) +#endif +{ + mLength = aRhs.mLength; + mCapacity = aRhs.mCapacity; +#ifdef DEBUG + mReserved = aRhs.mReserved; +#endif + + if (aRhs.usingInlineStorage()) { + /* We can't move the buffer over in this case, so copy elements. */ + mBegin = static_cast<T*>(mStorage.addr()); + Impl::moveConstruct(mBegin, aRhs.beginNoCheck(), aRhs.endNoCheck()); + /* + * Leave aRhs's mLength, mBegin, mCapacity, and mReserved as they are. + * The elements in its in-line storage still need to be destroyed. + */ + } else { + /* + * Take src's buffer, and turn src into an empty vector using + * in-line storage. + */ + mBegin = aRhs.mBegin; + aRhs.mBegin = static_cast<T*>(aRhs.mStorage.addr()); + aRhs.mCapacity = kInlineCapacity; + aRhs.mLength = 0; +#ifdef DEBUG + aRhs.mReserved = 0; +#endif + } +} + +/* Move assignment. */ +template<typename T, size_t N, class AP> +MOZ_ALWAYS_INLINE Vector<T, N, AP>& +Vector<T, N, AP>::operator=(Vector&& aRhs) +{ + MOZ_ASSERT(this != &aRhs, "self-move assignment is prohibited"); + this->~Vector(); + new(KnownNotNull, this) Vector(Move(aRhs)); + return *this; +} + +template<typename T, size_t N, class AP> +MOZ_ALWAYS_INLINE +Vector<T, N, AP>::~Vector() +{ + MOZ_REENTRANCY_GUARD_ET_AL; + Impl::destroy(beginNoCheck(), endNoCheck()); + if (!usingInlineStorage()) { + this->free_(beginNoCheck()); + } +} + +template<typename T, size_t N, class AP> +MOZ_ALWAYS_INLINE void +Vector<T, N, AP>::reverse() { + MOZ_REENTRANCY_GUARD_ET_AL; + T* elems = mBegin; + size_t len = mLength; + size_t mid = len / 2; + for (size_t i = 0; i < mid; i++) { + Swap(elems[i], elems[len - i - 1]); + } +} + +/* + * This function will create a new heap buffer with capacity aNewCap, + * move all elements in the inline buffer to this new buffer, + * and fail on OOM. + */ +template<typename T, size_t N, class AP> +inline bool +Vector<T, N, AP>::convertToHeapStorage(size_t aNewCap) +{ + MOZ_ASSERT(usingInlineStorage()); + + /* Allocate buffer. */ + MOZ_ASSERT(!detail::CapacityHasExcessSpace<T>(aNewCap)); + T* newBuf = this->template pod_malloc<T>(aNewCap); + if (MOZ_UNLIKELY(!newBuf)) { + return false; + } + + /* Copy inline elements into heap buffer. */ + Impl::moveConstruct(newBuf, beginNoCheck(), endNoCheck()); + Impl::destroy(beginNoCheck(), endNoCheck()); + + /* Switch in heap buffer. */ + mBegin = newBuf; + /* mLength is unchanged. */ + mCapacity = aNewCap; + return true; +} + +template<typename T, size_t N, class AP> +MOZ_NEVER_INLINE bool +Vector<T, N, AP>::growStorageBy(size_t aIncr) +{ + MOZ_ASSERT(mLength + aIncr > mCapacity); + + /* + * When choosing a new capacity, its size should is as close to 2**N bytes + * as possible. 2**N-sized requests are best because they are unlikely to + * be rounded up by the allocator. Asking for a 2**N number of elements + * isn't as good, because if sizeof(T) is not a power-of-two that would + * result in a non-2**N request size. + */ + + size_t newCap; + + if (aIncr == 1) { + if (usingInlineStorage()) { + /* This case occurs in ~70--80% of the calls to this function. */ + size_t newSize = + tl::RoundUpPow2<(kInlineCapacity + 1) * sizeof(T)>::value; + newCap = newSize / sizeof(T); + goto convert; + } + + if (mLength == 0) { + /* This case occurs in ~0--10% of the calls to this function. */ + newCap = 1; + goto grow; + } + + /* This case occurs in ~15--20% of the calls to this function. */ + + /* + * Will mLength * 4 *sizeof(T) overflow? This condition limits a vector + * to 1GB of memory on a 32-bit system, which is a reasonable limit. It + * also ensures that + * + * static_cast<char*>(end()) - static_cast<char*>(begin()) + * + * doesn't overflow ptrdiff_t (see bug 510319). + */ + if (MOZ_UNLIKELY(mLength & tl::MulOverflowMask<4 * sizeof(T)>::value)) { + this->reportAllocOverflow(); + return false; + } + + /* + * If we reach here, the existing capacity will have a size that is already + * as close to 2^N as sizeof(T) will allow. Just double the capacity, and + * then there might be space for one more element. + */ + newCap = mLength * 2; + if (detail::CapacityHasExcessSpace<T>(newCap)) { + newCap += 1; + } + } else { + /* This case occurs in ~2% of the calls to this function. */ + size_t newMinCap = mLength + aIncr; + + /* Did mLength + aIncr overflow? Will newCap * sizeof(T) overflow? */ + if (MOZ_UNLIKELY(newMinCap < mLength || + newMinCap & tl::MulOverflowMask<2 * sizeof(T)>::value)) + { + this->reportAllocOverflow(); + return false; + } + + size_t newMinSize = newMinCap * sizeof(T); + size_t newSize = RoundUpPow2(newMinSize); + newCap = newSize / sizeof(T); + } + + if (usingInlineStorage()) { +convert: + return convertToHeapStorage(newCap); + } + +grow: + return Impl::growTo(*this, newCap); +} + +template<typename T, size_t N, class AP> +inline bool +Vector<T, N, AP>::initCapacity(size_t aRequest) +{ + MOZ_ASSERT(empty()); + MOZ_ASSERT(usingInlineStorage()); + if (aRequest == 0) { + return true; + } + T* newbuf = this->template pod_malloc<T>(aRequest); + if (MOZ_UNLIKELY(!newbuf)) { + return false; + } + mBegin = newbuf; + mCapacity = aRequest; +#ifdef DEBUG + mReserved = aRequest; +#endif + return true; +} + +template<typename T, size_t N, class AP> +inline bool +Vector<T, N, AP>::initLengthUninitialized(size_t aRequest) +{ + if (!initCapacity(aRequest)) { + return false; + } + infallibleGrowByUninitialized(aRequest); + return true; +} + +template<typename T, size_t N, class AP> +inline bool +Vector<T, N, AP>::maybeCheckSimulatedOOM(size_t aRequestedSize) +{ + if (aRequestedSize <= N) { + return true; + } + +#ifdef DEBUG + if (aRequestedSize <= mReserved) { + return true; + } +#endif + + return allocPolicy().checkSimulatedOOM(); +} + +template<typename T, size_t N, class AP> +inline bool +Vector<T, N, AP>::reserve(size_t aRequest) +{ + MOZ_REENTRANCY_GUARD_ET_AL; + if (aRequest > mCapacity) { + if (MOZ_UNLIKELY(!growStorageBy(aRequest - mLength))) { + return false; + } + } else if (!maybeCheckSimulatedOOM(aRequest)) { + return false; + } +#ifdef DEBUG + if (aRequest > mReserved) { + mReserved = aRequest; + } + MOZ_ASSERT(mLength <= mReserved); + MOZ_ASSERT(mReserved <= mCapacity); +#endif + return true; +} + +template<typename T, size_t N, class AP> +inline void +Vector<T, N, AP>::shrinkBy(size_t aIncr) +{ + MOZ_REENTRANCY_GUARD_ET_AL; + MOZ_ASSERT(aIncr <= mLength); + Impl::destroy(endNoCheck() - aIncr, endNoCheck()); + mLength -= aIncr; +} + +template<typename T, size_t N, class AP> +MOZ_ALWAYS_INLINE void +Vector<T, N, AP>::shrinkTo(size_t aNewLength) +{ + MOZ_ASSERT(aNewLength <= mLength); + shrinkBy(mLength - aNewLength); +} + +template<typename T, size_t N, class AP> +MOZ_ALWAYS_INLINE bool +Vector<T, N, AP>::growBy(size_t aIncr) +{ + MOZ_REENTRANCY_GUARD_ET_AL; + if (aIncr > mCapacity - mLength) { + if (MOZ_UNLIKELY(!growStorageBy(aIncr))) { + return false; + } + } else if (!maybeCheckSimulatedOOM(mLength + aIncr)) { + return false; + } + MOZ_ASSERT(mLength + aIncr <= mCapacity); + T* newend = endNoCheck() + aIncr; + Impl::initialize(endNoCheck(), newend); + mLength += aIncr; +#ifdef DEBUG + if (mLength > mReserved) { + mReserved = mLength; + } +#endif + return true; +} + +template<typename T, size_t N, class AP> +MOZ_ALWAYS_INLINE bool +Vector<T, N, AP>::growByUninitialized(size_t aIncr) +{ + MOZ_REENTRANCY_GUARD_ET_AL; + if (aIncr > mCapacity - mLength) { + if (MOZ_UNLIKELY(!growStorageBy(aIncr))) { + return false; + } + } else if (!maybeCheckSimulatedOOM(mLength + aIncr)) { + return false; + } +#ifdef DEBUG + if (mLength + aIncr > mReserved) { + mReserved = mLength + aIncr; + } +#endif + infallibleGrowByUninitialized(aIncr); + return true; +} + +template<typename T, size_t N, class AP> +MOZ_ALWAYS_INLINE void +Vector<T, N, AP>::infallibleGrowByUninitialized(size_t aIncr) +{ + MOZ_ASSERT(mLength + aIncr <= reserved()); + mLength += aIncr; +} + +template<typename T, size_t N, class AP> +inline bool +Vector<T, N, AP>::resize(size_t aNewLength) +{ + size_t curLength = mLength; + if (aNewLength > curLength) { + return growBy(aNewLength - curLength); + } + shrinkBy(curLength - aNewLength); + return true; +} + +template<typename T, size_t N, class AP> +MOZ_ALWAYS_INLINE bool +Vector<T, N, AP>::resizeUninitialized(size_t aNewLength) +{ + size_t curLength = mLength; + if (aNewLength > curLength) { + return growByUninitialized(aNewLength - curLength); + } + shrinkBy(curLength - aNewLength); + return true; +} + +template<typename T, size_t N, class AP> +inline void +Vector<T, N, AP>::clear() +{ + MOZ_REENTRANCY_GUARD_ET_AL; + Impl::destroy(beginNoCheck(), endNoCheck()); + mLength = 0; +} + +template<typename T, size_t N, class AP> +inline void +Vector<T, N, AP>::clearAndFree() +{ + clear(); + + if (usingInlineStorage()) { + return; + } + this->free_(beginNoCheck()); + mBegin = static_cast<T*>(mStorage.addr()); + mCapacity = kInlineCapacity; +#ifdef DEBUG + mReserved = 0; +#endif +} + +template<typename T, size_t N, class AP> +inline void +Vector<T, N, AP>::podResizeToFit() +{ + // This function is only defined if IsPod is true and will fail to compile + // otherwise. + Impl::podResizeToFit(*this); +} + +template<typename T, size_t N, class AP> +inline bool +Vector<T, N, AP>::canAppendWithoutRealloc(size_t aNeeded) const +{ + return mLength + aNeeded <= mCapacity; +} + +template<typename T, size_t N, class AP> +template<typename U, size_t O, class BP> +MOZ_ALWAYS_INLINE void +Vector<T, N, AP>::internalAppendAll(const Vector<U, O, BP>& aOther) +{ + internalAppend(aOther.begin(), aOther.length()); +} + +template<typename T, size_t N, class AP> +template<typename U> +MOZ_ALWAYS_INLINE void +Vector<T, N, AP>::internalAppend(U&& aU) +{ + MOZ_ASSERT(mLength + 1 <= mReserved); + MOZ_ASSERT(mReserved <= mCapacity); + Impl::new_(endNoCheck(), Forward<U>(aU)); + ++mLength; +} + +template<typename T, size_t N, class AP> +MOZ_ALWAYS_INLINE bool +Vector<T, N, AP>::appendN(const T& aT, size_t aNeeded) +{ + MOZ_REENTRANCY_GUARD_ET_AL; + if (mLength + aNeeded > mCapacity) { + if (MOZ_UNLIKELY(!growStorageBy(aNeeded))) { + return false; + } + } else if (!maybeCheckSimulatedOOM(mLength + aNeeded)) { + return false; + } +#ifdef DEBUG + if (mLength + aNeeded > mReserved) { + mReserved = mLength + aNeeded; + } +#endif + internalAppendN(aT, aNeeded); + return true; +} + +template<typename T, size_t N, class AP> +MOZ_ALWAYS_INLINE void +Vector<T, N, AP>::internalAppendN(const T& aT, size_t aNeeded) +{ + MOZ_ASSERT(mLength + aNeeded <= mReserved); + MOZ_ASSERT(mReserved <= mCapacity); + Impl::copyConstructN(endNoCheck(), aNeeded, aT); + mLength += aNeeded; +} + +template<typename T, size_t N, class AP> +template<typename U> +inline T* +Vector<T, N, AP>::insert(T* aP, U&& aVal) +{ + MOZ_ASSERT(begin() <= aP); + MOZ_ASSERT(aP <= end()); + size_t pos = aP - begin(); + MOZ_ASSERT(pos <= mLength); + size_t oldLength = mLength; + if (pos == oldLength) { + if (!append(Forward<U>(aVal))) { + return nullptr; + } + } else { + T oldBack = Move(back()); + if (!append(Move(oldBack))) { /* Dup the last element. */ + return nullptr; + } + for (size_t i = oldLength; i > pos; --i) { + (*this)[i] = Move((*this)[i - 1]); + } + (*this)[pos] = Forward<U>(aVal); + } + return begin() + pos; +} + +template<typename T, size_t N, class AP> +inline void +Vector<T, N, AP>::erase(T* aIt) +{ + MOZ_ASSERT(begin() <= aIt); + MOZ_ASSERT(aIt < end()); + while (aIt + 1 < end()) { + *aIt = Move(*(aIt + 1)); + ++aIt; + } + popBack(); +} + +template<typename T, size_t N, class AP> +inline void +Vector<T, N, AP>::erase(T* aBegin, T* aEnd) +{ + MOZ_ASSERT(begin() <= aBegin); + MOZ_ASSERT(aBegin <= aEnd); + MOZ_ASSERT(aEnd <= end()); + while (aEnd < end()) { + *aBegin++ = Move(*aEnd++); + } + shrinkBy(aEnd - aBegin); +} + +template<typename T, size_t N, class AP> +template<typename U> +MOZ_ALWAYS_INLINE bool +Vector<T, N, AP>::append(const U* aInsBegin, const U* aInsEnd) +{ + MOZ_REENTRANCY_GUARD_ET_AL; + size_t aNeeded = PointerRangeSize(aInsBegin, aInsEnd); + if (mLength + aNeeded > mCapacity) { + if (MOZ_UNLIKELY(!growStorageBy(aNeeded))) { + return false; + } + } else if (!maybeCheckSimulatedOOM(mLength + aNeeded)) { + return false; + } +#ifdef DEBUG + if (mLength + aNeeded > mReserved) { + mReserved = mLength + aNeeded; + } +#endif + internalAppend(aInsBegin, aNeeded); + return true; +} + +template<typename T, size_t N, class AP> +template<typename U> +MOZ_ALWAYS_INLINE void +Vector<T, N, AP>::internalAppend(const U* aInsBegin, size_t aInsLength) +{ + MOZ_ASSERT(mLength + aInsLength <= mReserved); + MOZ_ASSERT(mReserved <= mCapacity); + Impl::copyConstruct(endNoCheck(), aInsBegin, aInsBegin + aInsLength); + mLength += aInsLength; +} + +template<typename T, size_t N, class AP> +template<typename U> +MOZ_ALWAYS_INLINE bool +Vector<T, N, AP>::append(U&& aU) +{ + MOZ_REENTRANCY_GUARD_ET_AL; + if (mLength == mCapacity) { + if (MOZ_UNLIKELY(!growStorageBy(1))) { + return false; + } + } else if (!maybeCheckSimulatedOOM(mLength + 1)) { + return false; + } +#ifdef DEBUG + if (mLength + 1 > mReserved) { + mReserved = mLength + 1; + } +#endif + internalAppend(Forward<U>(aU)); + return true; +} + +template<typename T, size_t N, class AP> +template<typename U, size_t O, class BP> +MOZ_ALWAYS_INLINE bool +Vector<T, N, AP>::appendAll(const Vector<U, O, BP>& aOther) +{ + return append(aOther.begin(), aOther.length()); +} + +template<typename T, size_t N, class AP> +template<class U> +MOZ_ALWAYS_INLINE bool +Vector<T, N, AP>::append(const U* aInsBegin, size_t aInsLength) +{ + return append(aInsBegin, aInsBegin + aInsLength); +} + +template<typename T, size_t N, class AP> +MOZ_ALWAYS_INLINE void +Vector<T, N, AP>::popBack() +{ + MOZ_REENTRANCY_GUARD_ET_AL; + MOZ_ASSERT(!empty()); + --mLength; + endNoCheck()->~T(); +} + +template<typename T, size_t N, class AP> +MOZ_ALWAYS_INLINE T +Vector<T, N, AP>::popCopy() +{ + T ret = back(); + popBack(); + return ret; +} + +template<typename T, size_t N, class AP> +inline T* +Vector<T, N, AP>::extractRawBuffer() +{ + MOZ_REENTRANCY_GUARD_ET_AL; + + if (usingInlineStorage()) { + return nullptr; + } + + T* ret = mBegin; + mBegin = static_cast<T*>(mStorage.addr()); + mLength = 0; + mCapacity = kInlineCapacity; +#ifdef DEBUG + mReserved = 0; +#endif + return ret; +} + +template<typename T, size_t N, class AP> +inline T* +Vector<T, N, AP>::extractOrCopyRawBuffer() +{ + if (T* ret = extractRawBuffer()) { + return ret; + } + + MOZ_REENTRANCY_GUARD_ET_AL; + + T* copy = this->template pod_malloc<T>(mLength); + if (!copy) { + return nullptr; + } + + Impl::moveConstruct(copy, beginNoCheck(), endNoCheck()); + Impl::destroy(beginNoCheck(), endNoCheck()); + mBegin = static_cast<T*>(mStorage.addr()); + mLength = 0; + mCapacity = kInlineCapacity; +#ifdef DEBUG + mReserved = 0; +#endif + return copy; +} + +template<typename T, size_t N, class AP> +inline void +Vector<T, N, AP>::replaceRawBuffer(T* aP, size_t aLength) +{ + MOZ_REENTRANCY_GUARD_ET_AL; + + /* Destroy what we have. */ + Impl::destroy(beginNoCheck(), endNoCheck()); + if (!usingInlineStorage()) { + this->free_(beginNoCheck()); + } + + /* Take in the new buffer. */ + if (aLength <= kInlineCapacity) { + /* + * We convert to inline storage if possible, even though aP might + * otherwise be acceptable. Maybe this behaviour should be + * specifiable with an argument to this function. + */ + mBegin = static_cast<T*>(mStorage.addr()); + mLength = aLength; + mCapacity = kInlineCapacity; + Impl::moveConstruct(mBegin, aP, aP + aLength); + Impl::destroy(aP, aP + aLength); + this->free_(aP); + } else { + mBegin = aP; + mLength = aLength; + mCapacity = aLength; + } +#ifdef DEBUG + mReserved = aLength; +#endif +} + +template<typename T, size_t N, class AP> +inline size_t +Vector<T, N, AP>::sizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const +{ + return usingInlineStorage() ? 0 : aMallocSizeOf(beginNoCheck()); +} + +template<typename T, size_t N, class AP> +inline size_t +Vector<T, N, AP>::sizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const +{ + return aMallocSizeOf(this) + sizeOfExcludingThis(aMallocSizeOf); +} + +template<typename T, size_t N, class AP> +inline void +Vector<T, N, AP>::swap(Vector& aOther) +{ + static_assert(N == 0, + "still need to implement this for N != 0"); + + // This only works when inline storage is always empty. + if (!usingInlineStorage() && aOther.usingInlineStorage()) { + aOther.mBegin = mBegin; + mBegin = inlineStorage(); + } else if (usingInlineStorage() && !aOther.usingInlineStorage()) { + mBegin = aOther.mBegin; + aOther.mBegin = aOther.inlineStorage(); + } else if (!usingInlineStorage() && !aOther.usingInlineStorage()) { + Swap(mBegin, aOther.mBegin); + } else { + // This case is a no-op, since we'd set both to use their inline storage. + } + + Swap(mLength, aOther.mLength); + Swap(mCapacity, aOther.mCapacity); +#ifdef DEBUG + Swap(mReserved, aOther.mReserved); +#endif +} + +} // namespace mozilla + +#ifdef _MSC_VER +#pragma warning(pop) +#endif + +#endif /* mozilla_Vector_h */ diff --git a/mfbt/WeakPtr.h b/mfbt/WeakPtr.h new file mode 100644 index 000000000..ef0c19f4e --- /dev/null +++ b/mfbt/WeakPtr.h @@ -0,0 +1,283 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* Weak pointer functionality, implemented as a mixin for use with any class. */ + +/** + * SupportsWeakPtr lets you have a pointer to an object 'Foo' without affecting + * its lifetime. It works by creating a single shared reference counted object + * (WeakReference) that each WeakPtr will access 'Foo' through. This lets 'Foo' + * clear the pointer in the WeakReference without having to know about all of + * the WeakPtrs to it and allows the WeakReference to live beyond the lifetime + * of 'Foo'. + * + * PLEASE NOTE: This weak pointer implementation is not thread-safe. + * + * Note that when deriving from SupportsWeakPtr you should add + * MOZ_DECLARE_WEAKREFERENCE_TYPENAME(ClassName) to the public section of your + * class, where ClassName is the name of your class. + * + * The overhead of WeakPtr is that accesses to 'Foo' becomes an additional + * dereference, and an additional heap allocated pointer sized object shared + * between all of the WeakPtrs. + * + * Example of usage: + * + * // To have a class C support weak pointers, inherit from + * // SupportsWeakPtr<C>. + * class C : public SupportsWeakPtr<C> + * { + * public: + * MOZ_DECLARE_WEAKREFERENCE_TYPENAME(C) + * int mNum; + * void act(); + * }; + * + * C* ptr = new C(); + * + * // Get weak pointers to ptr. The first time a weak pointer + * // is obtained, a reference counted WeakReference object is created that + * // can live beyond the lifetime of 'ptr'. The WeakReference + * // object will be notified of 'ptr's destruction. + * WeakPtr<C> weak = ptr; + * WeakPtr<C> other = ptr; + * + * // Test a weak pointer for validity before using it. + * if (weak) { + * weak->mNum = 17; + * weak->act(); + * } + * + * // Destroying the underlying object clears weak pointers to it. + * delete ptr; + * + * MOZ_ASSERT(!weak, "Deleting |ptr| clears weak pointers to it."); + * MOZ_ASSERT(!other, "Deleting |ptr| clears all weak pointers to it."); + * + * WeakPtr is typesafe and may be used with any class. It is not required that + * the class be reference-counted or allocated in any particular way. + * + * The API was loosely inspired by Chromium's weak_ptr.h: + * http://src.chromium.org/svn/trunk/src/base/memory/weak_ptr.h + */ + +#ifndef mozilla_WeakPtr_h +#define mozilla_WeakPtr_h + +#include "mozilla/ArrayUtils.h" +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" +#include "mozilla/RefCounted.h" +#include "mozilla/RefPtr.h" +#include "mozilla/TypeTraits.h" + +#include <string.h> + +// Weak referencing is not implemeted as thread safe. When a WeakPtr +// is created or dereferenced on thread A but the real object is just +// being Released() on thread B, there is a possibility of a race +// when the proxy object (detail::WeakReference) is notified about +// the real object destruction just between when thread A is storing +// the object pointer locally and is about to add a reference to it. +// +// Hence, a non-null weak proxy object is considered to have a single +// "owning thread". It means that each query for a weak reference, +// its dereference, and destruction of the real object must all happen +// on a single thread. The following macros implement assertions for +// checking these conditions. +// +// We disable this on MinGW. MinGW has two threading models: win32 +// API based, which disables std::thread; and POSIX based which +// enables it but requires an emulation library (winpthreads). +// Rather than attempting to switch to pthread emulation at this point, +// we are disabling the std::thread based assertion checking. +// +// In the future, to enable it we could +// a. have libgcc/stdc++ support win32 threads natively +// b. switch to POSIX-based threading in MinGW with pthread emulation +// c. refactor it to not use std::thread + +#if !defined(__MINGW32__) && (defined(DEBUG) || (defined(NIGHTLY_BUILD) && !defined(MOZ_PROFILING))) + +#include <thread> +#define MOZ_WEAKPTR_DECLARE_THREAD_SAFETY_CHECK \ + std::thread::id _owningThread; \ + bool _empty; // If it was initialized as a placeholder with mPtr = nullptr. +#define MOZ_WEAKPTR_INIT_THREAD_SAFETY_CHECK() \ + do { \ + _owningThread = std::this_thread::get_id(); \ + _empty = !p; \ + } while (false) +#define MOZ_WEAKPTR_ASSERT_THREAD_SAFETY() \ + MOZ_DIAGNOSTIC_ASSERT(_empty || _owningThread == std::this_thread::get_id(), \ + "WeakPtr used on multiple threads") +#define MOZ_WEAKPTR_ASSERT_THREAD_SAFETY_DELEGATED(that) \ + (that)->AssertThreadSafety(); + +#define MOZ_WEAKPTR_THREAD_SAFETY_CHECKING 1 + +#else + +#define MOZ_WEAKPTR_DECLARE_THREAD_SAFETY_CHECK +#define MOZ_WEAKPTR_INIT_THREAD_SAFETY_CHECK() do { } while (false) +#define MOZ_WEAKPTR_ASSERT_THREAD_SAFETY() do { } while (false) +#define MOZ_WEAKPTR_ASSERT_THREAD_SAFETY_DELEGATED(that) do { } while (false) + +#endif + +namespace mozilla { + +template <typename T> class WeakPtr; +template <typename T> class SupportsWeakPtr; + +#ifdef MOZ_REFCOUNTED_LEAK_CHECKING +#define MOZ_DECLARE_WEAKREFERENCE_TYPENAME(T) \ + static const char* weakReferenceTypeName() { return "WeakReference<" #T ">"; } +#else +#define MOZ_DECLARE_WEAKREFERENCE_TYPENAME(T) +#endif + +namespace detail { + +// This can live beyond the lifetime of the class derived from +// SupportsWeakPtr. +template<class T> +class WeakReference : public ::mozilla::RefCounted<WeakReference<T> > +{ +public: + explicit WeakReference(T* p) : mPtr(p) + { + MOZ_WEAKPTR_INIT_THREAD_SAFETY_CHECK(); + } + + T* get() const { + MOZ_WEAKPTR_ASSERT_THREAD_SAFETY(); + return mPtr; + } + +#ifdef MOZ_REFCOUNTED_LEAK_CHECKING + const char* typeName() const + { + // The first time this is called mPtr is null, so don't + // invoke any methods on mPtr. + return T::weakReferenceTypeName(); + } + size_t typeSize() const { return sizeof(*this); } +#endif + +#ifdef MOZ_WEAKPTR_THREAD_SAFETY_CHECKING + void AssertThreadSafety() { MOZ_WEAKPTR_ASSERT_THREAD_SAFETY(); } +#endif + +private: + friend class mozilla::SupportsWeakPtr<T>; + + void detach() { + MOZ_WEAKPTR_ASSERT_THREAD_SAFETY(); + mPtr = nullptr; + } + + T* MOZ_NON_OWNING_REF mPtr; + MOZ_WEAKPTR_DECLARE_THREAD_SAFETY_CHECK +}; + +} // namespace detail + +template <typename T> +class SupportsWeakPtr +{ +protected: + ~SupportsWeakPtr() + { + static_assert(IsBaseOf<SupportsWeakPtr<T>, T>::value, + "T must derive from SupportsWeakPtr<T>"); + if (mSelfReferencingWeakPtr) { + mSelfReferencingWeakPtr.mRef->detach(); + } + } + +private: + const WeakPtr<T>& SelfReferencingWeakPtr() + { + if (!mSelfReferencingWeakPtr) { + mSelfReferencingWeakPtr.mRef = new detail::WeakReference<T>(static_cast<T*>(this)); + } else { + MOZ_WEAKPTR_ASSERT_THREAD_SAFETY_DELEGATED(mSelfReferencingWeakPtr.mRef); + } + return mSelfReferencingWeakPtr; + } + + const WeakPtr<const T>& SelfReferencingWeakPtr() const + { + const WeakPtr<T>& p = const_cast<SupportsWeakPtr*>(this)->SelfReferencingWeakPtr(); + return reinterpret_cast<const WeakPtr<const T>&>(p); + } + + friend class WeakPtr<T>; + friend class WeakPtr<const T>; + + WeakPtr<T> mSelfReferencingWeakPtr; +}; + +template <typename T> +class WeakPtr +{ + typedef detail::WeakReference<T> WeakReference; + +public: + WeakPtr& operator=(const WeakPtr& aOther) + { + mRef = aOther.mRef; + MOZ_WEAKPTR_ASSERT_THREAD_SAFETY_DELEGATED(mRef); + return *this; + } + + WeakPtr(const WeakPtr& aOther) + { + // The thread safety check is performed inside of the operator= method. + *this = aOther; + } + + WeakPtr& operator=(T* aOther) + { + if (aOther) { + *this = aOther->SelfReferencingWeakPtr(); + } else if (!mRef || mRef->get()) { + // Ensure that mRef is dereferenceable in the uninitialized state. + mRef = new WeakReference(nullptr); + } + // The thread safety check happens inside SelfReferencingWeakPtr + // or is initialized in the WeakReference constructor. + return *this; + } + + MOZ_IMPLICIT WeakPtr(T* aOther) + { + *this = aOther; + MOZ_WEAKPTR_ASSERT_THREAD_SAFETY_DELEGATED(mRef); + } + + // Ensure that mRef is dereferenceable in the uninitialized state. + WeakPtr() : mRef(new WeakReference(nullptr)) {} + + operator T*() const { return mRef->get(); } + T& operator*() const { return *mRef->get(); } + + T* operator->() const MOZ_NO_ADDREF_RELEASE_ON_RETURN { return mRef->get(); } + + T* get() const { return mRef->get(); } + +private: + friend class SupportsWeakPtr<T>; + + explicit WeakPtr(const RefPtr<WeakReference>& aOther) : mRef(aOther) {} + + RefPtr<WeakReference> mRef; +}; + +} // namespace mozilla + +#endif /* mozilla_WeakPtr_h */ diff --git a/mfbt/WindowsVersion.h b/mfbt/WindowsVersion.h new file mode 100644 index 000000000..f8b071861 --- /dev/null +++ b/mfbt/WindowsVersion.h @@ -0,0 +1,230 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef mozilla_WindowsVersion_h +#define mozilla_WindowsVersion_h + +#include "mozilla/Attributes.h" +#include <stdint.h> +#include <windows.h> + +namespace mozilla { + +inline bool +IsWindowsVersionOrLater(uint32_t aVersion) +{ + static uint32_t minVersion = 0; + static uint32_t maxVersion = UINT32_MAX; + + if (minVersion >= aVersion) { + return true; + } + + if (aVersion >= maxVersion) { + return false; + } + + OSVERSIONINFOEX info; + ZeroMemory(&info, sizeof(OSVERSIONINFOEX)); + info.dwOSVersionInfoSize = sizeof(OSVERSIONINFOEX); + info.dwMajorVersion = aVersion >> 24; + info.dwMinorVersion = (aVersion >> 16) & 0xFF; + info.wServicePackMajor = (aVersion >> 8) & 0xFF; + info.wServicePackMinor = aVersion & 0xFF; + + DWORDLONG conditionMask = 0; + VER_SET_CONDITION(conditionMask, VER_MAJORVERSION, VER_GREATER_EQUAL); + VER_SET_CONDITION(conditionMask, VER_MINORVERSION, VER_GREATER_EQUAL); + VER_SET_CONDITION(conditionMask, VER_SERVICEPACKMAJOR, VER_GREATER_EQUAL); + VER_SET_CONDITION(conditionMask, VER_SERVICEPACKMINOR, VER_GREATER_EQUAL); + + if (VerifyVersionInfo(&info, + VER_MAJORVERSION | VER_MINORVERSION | + VER_SERVICEPACKMAJOR | VER_SERVICEPACKMINOR, + conditionMask)) { + minVersion = aVersion; + return true; + } + + maxVersion = aVersion; + return false; +} + +inline bool +IsWindowsBuildOrLater(uint32_t aBuild) +{ + static uint32_t minBuild = 0; + static uint32_t maxBuild = UINT32_MAX; + + if (minBuild >= aBuild) { + return true; + } + + if (aBuild >= maxBuild) { + return false; + } + + OSVERSIONINFOEX info; + ZeroMemory(&info, sizeof(OSVERSIONINFOEX)); + info.dwOSVersionInfoSize = sizeof(OSVERSIONINFOEX); + info.dwBuildNumber = aBuild; + + DWORDLONG conditionMask = 0; + VER_SET_CONDITION(conditionMask, VER_BUILDNUMBER, VER_GREATER_EQUAL); + + if (VerifyVersionInfo(&info, VER_BUILDNUMBER, conditionMask)) { + minBuild = aBuild; + return true; + } + + maxBuild = aBuild; + return false; +} + +#if defined(_M_X64) || defined(_M_AMD64) +// We support only Win7 or later on Win64. +MOZ_ALWAYS_INLINE bool +IsXPSP3OrLater() +{ + return true; +} + +MOZ_ALWAYS_INLINE bool +IsWin2003OrLater() +{ + return true; +} + +MOZ_ALWAYS_INLINE bool +IsWin2003SP2OrLater() +{ + return true; +} + +MOZ_ALWAYS_INLINE bool +IsVistaOrLater() +{ + return true; +} + +MOZ_ALWAYS_INLINE bool +IsVistaSP1OrLater() +{ + return true; +} + +MOZ_ALWAYS_INLINE bool +IsWin7OrLater() +{ + return true; +} +#else +MOZ_ALWAYS_INLINE bool +IsXPSP3OrLater() +{ + return IsWindowsVersionOrLater(0x05010300ul); +} + +MOZ_ALWAYS_INLINE bool +IsWin2003OrLater() +{ + return IsWindowsVersionOrLater(0x05020000ul); +} + +MOZ_ALWAYS_INLINE bool +IsWin2003SP2OrLater() +{ + return IsWindowsVersionOrLater(0x05020200ul); +} + +MOZ_ALWAYS_INLINE bool +IsVistaOrLater() +{ + return IsWindowsVersionOrLater(0x06000000ul); +} + +MOZ_ALWAYS_INLINE bool +IsVistaSP1OrLater() +{ + return IsWindowsVersionOrLater(0x06000100ul); +} + +MOZ_ALWAYS_INLINE bool +IsWin7OrLater() +{ + return IsWindowsVersionOrLater(0x06010000ul); +} +#endif + +MOZ_ALWAYS_INLINE bool +IsWin7SP1OrLater() +{ + return IsWindowsVersionOrLater(0x06010100ul); +} + +MOZ_ALWAYS_INLINE bool +IsWin8OrLater() +{ + return IsWindowsVersionOrLater(0x06020000ul); +} + +MOZ_ALWAYS_INLINE bool +IsWin8Point1OrLater() +{ + return IsWindowsVersionOrLater(0x06030000ul); +} + +MOZ_ALWAYS_INLINE bool +IsWin10OrLater() +{ + return IsWindowsVersionOrLater(0x0a000000ul); +} + +MOZ_ALWAYS_INLINE bool +IsNotWin7PreRTM() +{ + return IsWin7SP1OrLater() || !IsWin7OrLater() || + IsWindowsBuildOrLater(7600); +} + +MOZ_ALWAYS_INLINE bool +IsWin7AndPre2000Compatible() { + /* + * See Bug 1279171. + * We'd like to avoid using WMF on specific OS version when compatibility + * mode is in effect. The purpose of this function is to check if FF runs on + * Win7 OS with application compatibility mode being set to 95/98/ME. + * Those compatibility mode options (95/98/ME) can only display and + * be selected for 32-bit application. + * If the compatibility mode is in effect, the GetVersionEx function will + * report the OS as it identifies itself, which may not be the OS that is + * installed. + * Note : 1) We only target for Win7 build number greater than 7600. + * 2) GetVersionEx may be altered or unavailable for release after + * Win8.1. Set pragma to avoid build warning as error. + */ + bool isWin7 = IsNotWin7PreRTM() && !IsWin8OrLater(); + if (!isWin7) { + return false; + } + + OSVERSIONINFOEX info; + ZeroMemory(&info, sizeof(OSVERSIONINFOEX)); + + info.dwOSVersionInfoSize = sizeof(OSVERSIONINFOEX); +#pragma warning(push) +#pragma warning(disable:4996) + bool success = GetVersionEx((LPOSVERSIONINFO) &info); +#pragma warning(pop) + if (!success) { + return false; + } + return info.dwMajorVersion < 5; +} + +} // namespace mozilla + +#endif /* mozilla_WindowsVersion_h */ diff --git a/mfbt/XorShift128PlusRNG.h b/mfbt/XorShift128PlusRNG.h new file mode 100644 index 000000000..2f182f0fb --- /dev/null +++ b/mfbt/XorShift128PlusRNG.h @@ -0,0 +1,121 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* The xorshift128+ pseudo-random number generator. */ + +#ifndef mozilla_XorShift128Plus_h +#define mozilla_XorShift128Plus_h + +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" +#include "mozilla/FloatingPoint.h" + +#include <inttypes.h> + +namespace mozilla { +namespace non_crypto { + +/* + * A stream of pseudo-random numbers generated using the xorshift+ technique + * described here: + * + * Vigna, Sebastiano (2014). "Further scramblings of Marsaglia's xorshift + * generators". arXiv:1404.0390 (http://arxiv.org/abs/1404.0390) + * + * That paper says: + * + * In particular, we propose a tightly coded xorshift128+ generator that + * does not fail systematically any test from the BigCrush suite of TestU01 + * (even reversed) and generates 64 pseudorandom bits in 1.10 ns on an + * Intel(R) Core(TM) i7-4770 CPU @3.40GHz (Haswell). It is the fastest + * generator we are aware of with such empirical statistical properties. + * + * The stream of numbers produced by this method repeats every 2**128 - 1 calls + * (i.e. never, for all practical purposes). Zero appears 2**64 - 1 times in + * this period; all other numbers appear 2**64 times. Additionally, each *bit* + * in the produced numbers repeats every 2**128 - 1 calls. + * + * This generator is not suitable as a cryptographically secure random number + * generator. + */ +class XorShift128PlusRNG { + uint64_t mState[2]; + + public: + /* + * Construct a xorshift128+ pseudo-random number stream using |aInitial0| and + * |aInitial1| as the initial state. These MUST NOT both be zero. + * + * If the initial states contain many zeros, for a few iterations you'll see + * many zeroes in the generated numbers. It's suggested to seed a SplitMix64 + * generator <http://xorshift.di.unimi.it/splitmix64.c> and use its first two + * outputs to seed xorshift128+. + */ + XorShift128PlusRNG(uint64_t aInitial0, uint64_t aInitial1) { + setState(aInitial0, aInitial1); + } + + /** + * Return a pseudo-random 64-bit number. + */ + uint64_t next() { + /* + * The offsetOfState*() methods below are provided so that exceedingly-rare + * callers that want to observe or poke at RNG state in C++ type-system- + * ignoring means can do so. Don't change the next() or nextDouble() + * algorithms without altering code that uses offsetOfState*()! + */ + uint64_t s1 = mState[0]; + const uint64_t s0 = mState[1]; + mState[0] = s0; + s1 ^= s1 << 23; + mState[1] = s1 ^ s0 ^ (s1 >> 17) ^ (s0 >> 26); + return mState[1] + s0; + } + + /* + * Return a pseudo-random floating-point value in the range [0, 1). More + * precisely, choose an integer in the range [0, 2**53) and divide it by + * 2**53. Given the 2**128 - 1 period noted above, the produced doubles are + * all but uniformly distributed in this range. + */ + double nextDouble() { + /* + * Because the IEEE 64-bit floating point format stores the leading '1' bit + * of the mantissa implicitly, it effectively represents a mantissa in the + * range [0, 2**53) in only 52 bits. FloatingPoint<double>::kExponentShift + * is the width of the bitfield in the in-memory format, so we must add one + * to get the mantissa's range. + */ + static constexpr int kMantissaBits = + mozilla::FloatingPoint<double>::kExponentShift + 1; + uint64_t mantissa = next() & ((UINT64_C(1) << kMantissaBits) - 1); + return double(mantissa) / (UINT64_C(1) << kMantissaBits); + } + + /* + * Set the stream's current state to |aState0| and |aState1|. These must not + * both be zero; ideally, they should have an almost even mix of zero and one + * bits. + */ + void setState(uint64_t aState0, uint64_t aState1) { + MOZ_ASSERT(aState0 || aState1); + mState[0] = aState0; + mState[1] = aState1; + } + + static size_t offsetOfState0() { + return offsetof(XorShift128PlusRNG, mState[0]); + } + static size_t offsetOfState1() { + return offsetof(XorShift128PlusRNG, mState[1]); + } +}; + +} // namespace non_crypto +} // namespace mozilla + +#endif // mozilla_XorShift128Plus_h diff --git a/mfbt/decimal/Decimal.cpp b/mfbt/decimal/Decimal.cpp new file mode 100644 index 000000000..b08b4160f --- /dev/null +++ b/mfbt/decimal/Decimal.cpp @@ -0,0 +1,1050 @@ +/* + * Copyright (C) 2012 Google Inc. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Google Inc. nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include "Decimal.h" +#include "moz-decimal-utils.h" + +using namespace moz_decimal_utils; + +#include <algorithm> +#include <float.h> + +namespace blink { + +namespace DecimalPrivate { + +static int const ExponentMax = 1023; +static int const ExponentMin = -1023; +static int const Precision = 18; + +static const uint64_t MaxCoefficient = UINT64_C(0xDE0B6B3A763FFFF); // 999999999999999999 == 18 9's + +// This class handles Decimal special values. +class SpecialValueHandler { + STACK_ALLOCATED(); + WTF_MAKE_NONCOPYABLE(SpecialValueHandler); +public: + enum HandleResult { + BothFinite, + BothInfinity, + EitherNaN, + LHSIsInfinity, + RHSIsInfinity, + }; + + SpecialValueHandler(const Decimal& lhs, const Decimal& rhs); + HandleResult handle(); + Decimal value() const; + +private: + enum Result { + ResultIsLHS, + ResultIsRHS, + ResultIsUnknown, + }; + + const Decimal& m_lhs; + const Decimal& m_rhs; + Result m_result; +}; + +SpecialValueHandler::SpecialValueHandler(const Decimal& lhs, const Decimal& rhs) + : m_lhs(lhs), m_rhs(rhs), m_result(ResultIsUnknown) +{ +} + +SpecialValueHandler::HandleResult SpecialValueHandler::handle() +{ + if (m_lhs.isFinite() && m_rhs.isFinite()) + return BothFinite; + + const Decimal::EncodedData::FormatClass lhsClass = m_lhs.value().formatClass(); + const Decimal::EncodedData::FormatClass rhsClass = m_rhs.value().formatClass(); + if (lhsClass == Decimal::EncodedData::ClassNaN) { + m_result = ResultIsLHS; + return EitherNaN; + } + + if (rhsClass == Decimal::EncodedData::ClassNaN) { + m_result = ResultIsRHS; + return EitherNaN; + } + + if (lhsClass == Decimal::EncodedData::ClassInfinity) + return rhsClass == Decimal::EncodedData::ClassInfinity ? BothInfinity : LHSIsInfinity; + + if (rhsClass == Decimal::EncodedData::ClassInfinity) + return RHSIsInfinity; + + ASSERT_NOT_REACHED(); + return BothFinite; +} + +Decimal SpecialValueHandler::value() const +{ + switch (m_result) { + case ResultIsLHS: + return m_lhs; + case ResultIsRHS: + return m_rhs; + case ResultIsUnknown: + default: + ASSERT_NOT_REACHED(); + return m_lhs; + } +} + +// This class is used for 128 bit unsigned integer arithmetic. +class UInt128 { +public: + UInt128(uint64_t low, uint64_t high) + : m_high(high), m_low(low) + { + } + + UInt128& operator/=(uint32_t); + + uint64_t high() const { return m_high; } + uint64_t low() const { return m_low; } + + static UInt128 multiply(uint64_t u, uint64_t v) { return UInt128(u * v, multiplyHigh(u, v)); } + +private: + static uint32_t highUInt32(uint64_t x) { return static_cast<uint32_t>(x >> 32); } + static uint32_t lowUInt32(uint64_t x) { return static_cast<uint32_t>(x & ((static_cast<uint64_t>(1) << 32) - 1)); } + static uint64_t makeUInt64(uint32_t low, uint32_t high) { return low | (static_cast<uint64_t>(high) << 32); } + + static uint64_t multiplyHigh(uint64_t, uint64_t); + + uint64_t m_high; + uint64_t m_low; +}; + +UInt128& UInt128::operator/=(const uint32_t divisor) +{ + ASSERT(divisor); + + if (!m_high) { + m_low /= divisor; + return *this; + } + + uint32_t dividend[4]; + dividend[0] = lowUInt32(m_low); + dividend[1] = highUInt32(m_low); + dividend[2] = lowUInt32(m_high); + dividend[3] = highUInt32(m_high); + + uint32_t quotient[4]; + uint32_t remainder = 0; + for (int i = 3; i >= 0; --i) { + const uint64_t work = makeUInt64(dividend[i], remainder); + remainder = static_cast<uint32_t>(work % divisor); + quotient[i] = static_cast<uint32_t>(work / divisor); + } + m_low = makeUInt64(quotient[0], quotient[1]); + m_high = makeUInt64(quotient[2], quotient[3]); + return *this; +} + +// Returns high 64bit of 128bit product. +uint64_t UInt128::multiplyHigh(uint64_t u, uint64_t v) +{ + const uint64_t uLow = lowUInt32(u); + const uint64_t uHigh = highUInt32(u); + const uint64_t vLow = lowUInt32(v); + const uint64_t vHigh = highUInt32(v); + const uint64_t partialProduct = uHigh * vLow + highUInt32(uLow * vLow); + return uHigh * vHigh + highUInt32(partialProduct) + highUInt32(uLow * vHigh + lowUInt32(partialProduct)); +} + +static int countDigits(uint64_t x) +{ + int numberOfDigits = 0; + for (uint64_t powerOfTen = 1; x >= powerOfTen; powerOfTen *= 10) { + ++numberOfDigits; + if (powerOfTen >= std::numeric_limits<uint64_t>::max() / 10) + break; + } + return numberOfDigits; +} + +static uint64_t scaleDown(uint64_t x, int n) +{ + ASSERT(n >= 0); + while (n > 0 && x) { + x /= 10; + --n; + } + return x; +} + +static uint64_t scaleUp(uint64_t x, int n) +{ + ASSERT(n >= 0); + ASSERT(n <= Precision); + + uint64_t y = 1; + uint64_t z = 10; + for (;;) { + if (n & 1) + y = y * z; + + n >>= 1; + if (!n) + return x * y; + + z = z * z; + } +} + +} // namespace DecimalPrivate + +using namespace DecimalPrivate; + +Decimal::EncodedData::EncodedData(Sign sign, FormatClass formatClass) + : m_coefficient(0) + , m_exponent(0) + , m_formatClass(formatClass) + , m_sign(sign) +{ +} + +Decimal::EncodedData::EncodedData(Sign sign, int exponent, uint64_t coefficient) + : m_formatClass(coefficient ? ClassNormal : ClassZero) + , m_sign(sign) +{ + if (exponent >= ExponentMin && exponent <= ExponentMax) { + while (coefficient > MaxCoefficient) { + coefficient /= 10; + ++exponent; + } + } + + if (exponent > ExponentMax) { + m_coefficient = 0; + m_exponent = 0; + m_formatClass = ClassInfinity; + return; + } + + if (exponent < ExponentMin) { + m_coefficient = 0; + m_exponent = 0; + m_formatClass = ClassZero; + return; + } + + m_coefficient = coefficient; + m_exponent = static_cast<int16_t>(exponent); +} + +bool Decimal::EncodedData::operator==(const EncodedData& another) const +{ + return m_sign == another.m_sign + && m_formatClass == another.m_formatClass + && m_exponent == another.m_exponent + && m_coefficient == another.m_coefficient; +} + +Decimal::Decimal(int32_t i32) + : m_data(i32 < 0 ? Negative : Positive, 0, i32 < 0 ? static_cast<uint64_t>(-static_cast<int64_t>(i32)) : static_cast<uint64_t>(i32)) +{ +} + +Decimal::Decimal(Sign sign, int exponent, uint64_t coefficient) + : m_data(sign, coefficient ? exponent : 0, coefficient) +{ +} + +Decimal::Decimal(const EncodedData& data) + : m_data(data) +{ +} + +Decimal::Decimal(const Decimal& other) + : m_data(other.m_data) +{ +} + +Decimal& Decimal::operator=(const Decimal& other) +{ + m_data = other.m_data; + return *this; +} + +Decimal& Decimal::operator+=(const Decimal& other) +{ + m_data = (*this + other).m_data; + return *this; +} + +Decimal& Decimal::operator-=(const Decimal& other) +{ + m_data = (*this - other).m_data; + return *this; +} + +Decimal& Decimal::operator*=(const Decimal& other) +{ + m_data = (*this * other).m_data; + return *this; +} + +Decimal& Decimal::operator/=(const Decimal& other) +{ + m_data = (*this / other).m_data; + return *this; +} + +Decimal Decimal::operator-() const +{ + if (isNaN()) + return *this; + + Decimal result(*this); + result.m_data.setSign(invertSign(m_data.sign())); + return result; +} + +Decimal Decimal::operator+(const Decimal& rhs) const +{ + const Decimal& lhs = *this; + const Sign lhsSign = lhs.sign(); + const Sign rhsSign = rhs.sign(); + + SpecialValueHandler handler(lhs, rhs); + switch (handler.handle()) { + case SpecialValueHandler::BothFinite: + break; + + case SpecialValueHandler::BothInfinity: + return lhsSign == rhsSign ? lhs : nan(); + + case SpecialValueHandler::EitherNaN: + return handler.value(); + + case SpecialValueHandler::LHSIsInfinity: + return lhs; + + case SpecialValueHandler::RHSIsInfinity: + return rhs; + } + + const AlignedOperands alignedOperands = alignOperands(lhs, rhs); + + const uint64_t result = lhsSign == rhsSign + ? alignedOperands.lhsCoefficient + alignedOperands.rhsCoefficient + : alignedOperands.lhsCoefficient - alignedOperands.rhsCoefficient; + + if (lhsSign == Negative && rhsSign == Positive && !result) + return Decimal(Positive, alignedOperands.exponent, 0); + + return static_cast<int64_t>(result) >= 0 + ? Decimal(lhsSign, alignedOperands.exponent, result) + : Decimal(invertSign(lhsSign), alignedOperands.exponent, -static_cast<int64_t>(result)); +} + +Decimal Decimal::operator-(const Decimal& rhs) const +{ + const Decimal& lhs = *this; + const Sign lhsSign = lhs.sign(); + const Sign rhsSign = rhs.sign(); + + SpecialValueHandler handler(lhs, rhs); + switch (handler.handle()) { + case SpecialValueHandler::BothFinite: + break; + + case SpecialValueHandler::BothInfinity: + return lhsSign == rhsSign ? nan() : lhs; + + case SpecialValueHandler::EitherNaN: + return handler.value(); + + case SpecialValueHandler::LHSIsInfinity: + return lhs; + + case SpecialValueHandler::RHSIsInfinity: + return infinity(invertSign(rhsSign)); + } + + const AlignedOperands alignedOperands = alignOperands(lhs, rhs); + + const uint64_t result = lhsSign == rhsSign + ? alignedOperands.lhsCoefficient - alignedOperands.rhsCoefficient + : alignedOperands.lhsCoefficient + alignedOperands.rhsCoefficient; + + if (lhsSign == Negative && rhsSign == Negative && !result) + return Decimal(Positive, alignedOperands.exponent, 0); + + return static_cast<int64_t>(result) >= 0 + ? Decimal(lhsSign, alignedOperands.exponent, result) + : Decimal(invertSign(lhsSign), alignedOperands.exponent, -static_cast<int64_t>(result)); +} + +Decimal Decimal::operator*(const Decimal& rhs) const +{ + const Decimal& lhs = *this; + const Sign lhsSign = lhs.sign(); + const Sign rhsSign = rhs.sign(); + const Sign resultSign = lhsSign == rhsSign ? Positive : Negative; + + SpecialValueHandler handler(lhs, rhs); + switch (handler.handle()) { + case SpecialValueHandler::BothFinite: { + const uint64_t lhsCoefficient = lhs.m_data.coefficient(); + const uint64_t rhsCoefficient = rhs.m_data.coefficient(); + int resultExponent = lhs.exponent() + rhs.exponent(); + UInt128 work(UInt128::multiply(lhsCoefficient, rhsCoefficient)); + while (work.high()) { + work /= 10; + ++resultExponent; + } + return Decimal(resultSign, resultExponent, work.low()); + } + + case SpecialValueHandler::BothInfinity: + return infinity(resultSign); + + case SpecialValueHandler::EitherNaN: + return handler.value(); + + case SpecialValueHandler::LHSIsInfinity: + return rhs.isZero() ? nan() : infinity(resultSign); + + case SpecialValueHandler::RHSIsInfinity: + return lhs.isZero() ? nan() : infinity(resultSign); + } + + ASSERT_NOT_REACHED(); + return nan(); +} + +Decimal Decimal::operator/(const Decimal& rhs) const +{ + const Decimal& lhs = *this; + const Sign lhsSign = lhs.sign(); + const Sign rhsSign = rhs.sign(); + const Sign resultSign = lhsSign == rhsSign ? Positive : Negative; + + SpecialValueHandler handler(lhs, rhs); + switch (handler.handle()) { + case SpecialValueHandler::BothFinite: + break; + + case SpecialValueHandler::BothInfinity: + return nan(); + + case SpecialValueHandler::EitherNaN: + return handler.value(); + + case SpecialValueHandler::LHSIsInfinity: + return infinity(resultSign); + + case SpecialValueHandler::RHSIsInfinity: + return zero(resultSign); + } + + ASSERT(lhs.isFinite()); + ASSERT(rhs.isFinite()); + + if (rhs.isZero()) + return lhs.isZero() ? nan() : infinity(resultSign); + + int resultExponent = lhs.exponent() - rhs.exponent(); + + if (lhs.isZero()) + return Decimal(resultSign, resultExponent, 0); + + uint64_t remainder = lhs.m_data.coefficient(); + const uint64_t divisor = rhs.m_data.coefficient(); + uint64_t result = 0; + for (;;) { + while (remainder < divisor && result < MaxCoefficient / 10) { + remainder *= 10; + result *= 10; + --resultExponent; + } + if (remainder < divisor) + break; + uint64_t quotient = remainder / divisor; + if (result > MaxCoefficient - quotient) + break; + result += quotient; + remainder %= divisor; + if (!remainder) + break; + } + + if (remainder > divisor / 2) + ++result; + + return Decimal(resultSign, resultExponent, result); +} + +bool Decimal::operator==(const Decimal& rhs) const +{ + if (isNaN() || rhs.isNaN()) + return false; + return m_data == rhs.m_data || compareTo(rhs).isZero(); +} + +bool Decimal::operator!=(const Decimal& rhs) const +{ + if (isNaN() || rhs.isNaN()) + return true; + if (m_data == rhs.m_data) + return false; + const Decimal result = compareTo(rhs); + if (result.isNaN()) + return false; + return !result.isZero(); +} + +bool Decimal::operator<(const Decimal& rhs) const +{ + const Decimal result = compareTo(rhs); + if (result.isNaN()) + return false; + return !result.isZero() && result.isNegative(); +} + +bool Decimal::operator<=(const Decimal& rhs) const +{ + if (isNaN() || rhs.isNaN()) + return false; + if (m_data == rhs.m_data) + return true; + const Decimal result = compareTo(rhs); + if (result.isNaN()) + return false; + return result.isZero() || result.isNegative(); +} + +bool Decimal::operator>(const Decimal& rhs) const +{ + const Decimal result = compareTo(rhs); + if (result.isNaN()) + return false; + return !result.isZero() && result.isPositive(); +} + +bool Decimal::operator>=(const Decimal& rhs) const +{ + if (isNaN() || rhs.isNaN()) + return false; + if (m_data == rhs.m_data) + return true; + const Decimal result = compareTo(rhs); + if (result.isNaN()) + return false; + return result.isZero() || !result.isNegative(); +} + +Decimal Decimal::abs() const +{ + Decimal result(*this); + result.m_data.setSign(Positive); + return result; +} + +Decimal::AlignedOperands Decimal::alignOperands(const Decimal& lhs, const Decimal& rhs) +{ + ASSERT(lhs.isFinite()); + ASSERT(rhs.isFinite()); + + const int lhsExponent = lhs.exponent(); + const int rhsExponent = rhs.exponent(); + int exponent = std::min(lhsExponent, rhsExponent); + uint64_t lhsCoefficient = lhs.m_data.coefficient(); + uint64_t rhsCoefficient = rhs.m_data.coefficient(); + + if (lhsExponent > rhsExponent) { + const int numberOfLHSDigits = countDigits(lhsCoefficient); + if (numberOfLHSDigits) { + const int lhsShiftAmount = lhsExponent - rhsExponent; + const int overflow = numberOfLHSDigits + lhsShiftAmount - Precision; + if (overflow <= 0) { + lhsCoefficient = scaleUp(lhsCoefficient, lhsShiftAmount); + } else { + lhsCoefficient = scaleUp(lhsCoefficient, lhsShiftAmount - overflow); + rhsCoefficient = scaleDown(rhsCoefficient, overflow); + exponent += overflow; + } + } + + } else if (lhsExponent < rhsExponent) { + const int numberOfRHSDigits = countDigits(rhsCoefficient); + if (numberOfRHSDigits) { + const int rhsShiftAmount = rhsExponent - lhsExponent; + const int overflow = numberOfRHSDigits + rhsShiftAmount - Precision; + if (overflow <= 0) { + rhsCoefficient = scaleUp(rhsCoefficient, rhsShiftAmount); + } else { + rhsCoefficient = scaleUp(rhsCoefficient, rhsShiftAmount - overflow); + lhsCoefficient = scaleDown(lhsCoefficient, overflow); + exponent += overflow; + } + } + } + + AlignedOperands alignedOperands; + alignedOperands.exponent = exponent; + alignedOperands.lhsCoefficient = lhsCoefficient; + alignedOperands.rhsCoefficient = rhsCoefficient; + return alignedOperands; +} + +static bool isMultiplePowersOfTen(uint64_t coefficient, int n) +{ + return !coefficient || !(coefficient % scaleUp(1, n)); +} + +// Round toward positive infinity. +Decimal Decimal::ceil() const +{ + if (isSpecial()) + return *this; + + if (exponent() >= 0) + return *this; + + uint64_t result = m_data.coefficient(); + const int numberOfDigits = countDigits(result); + const int numberOfDropDigits = -exponent(); + if (numberOfDigits <= numberOfDropDigits) + return isPositive() ? Decimal(1) : zero(Positive); + + result = scaleDown(result, numberOfDropDigits); + if (isPositive() && !isMultiplePowersOfTen(m_data.coefficient(), numberOfDropDigits)) + ++result; + return Decimal(sign(), 0, result); +} + +Decimal Decimal::compareTo(const Decimal& rhs) const +{ + const Decimal result(*this - rhs); + switch (result.m_data.formatClass()) { + case EncodedData::ClassInfinity: + return result.isNegative() ? Decimal(-1) : Decimal(1); + + case EncodedData::ClassNaN: + case EncodedData::ClassNormal: + return result; + + case EncodedData::ClassZero: + return zero(Positive); + + default: + ASSERT_NOT_REACHED(); + return nan(); + } +} + +// Round toward negative infinity. +Decimal Decimal::floor() const +{ + if (isSpecial()) + return *this; + + if (exponent() >= 0) + return *this; + + uint64_t result = m_data.coefficient(); + const int numberOfDigits = countDigits(result); + const int numberOfDropDigits = -exponent(); + if (numberOfDigits < numberOfDropDigits) + return isPositive() ? zero(Positive) : Decimal(-1); + + result = scaleDown(result, numberOfDropDigits); + if (isNegative() && !isMultiplePowersOfTen(m_data.coefficient(), numberOfDropDigits)) + ++result; + return Decimal(sign(), 0, result); +} + +Decimal Decimal::fromDouble(double doubleValue) +{ + if (std::isfinite(doubleValue)) + return fromString(mozToString(doubleValue)); + + if (std::isinf(doubleValue)) + return infinity(doubleValue < 0 ? Negative : Positive); + + return nan(); +} + +Decimal Decimal::fromString(const String& str) +{ + int exponent = 0; + Sign exponentSign = Positive; + int numberOfDigits = 0; + int numberOfDigitsAfterDot = 0; + int numberOfExtraDigits = 0; + Sign sign = Positive; + + enum { + StateDigit, + StateDot, + StateDotDigit, + StateE, + StateEDigit, + StateESign, + StateSign, + StateStart, + StateZero, + } state = StateStart; + +#define HandleCharAndBreak(expected, nextState) \ + if (ch == expected) { \ + state = nextState; \ + break; \ + } + +#define HandleTwoCharsAndBreak(expected1, expected2, nextState) \ + if (ch == expected1 || ch == expected2) { \ + state = nextState; \ + break; \ + } + + uint64_t accumulator = 0; + for (unsigned index = 0; index < str.length(); ++index) { + const int ch = str[index]; + switch (state) { + case StateDigit: + if (ch >= '0' && ch <= '9') { + if (numberOfDigits < Precision) { + ++numberOfDigits; + accumulator *= 10; + accumulator += ch - '0'; + } else { + ++numberOfExtraDigits; + } + break; + } + + HandleCharAndBreak('.', StateDot); + HandleTwoCharsAndBreak('E', 'e', StateE); + return nan(); + + case StateDot: + case StateDotDigit: + if (ch >= '0' && ch <= '9') { + if (numberOfDigits < Precision) { + ++numberOfDigits; + ++numberOfDigitsAfterDot; + accumulator *= 10; + accumulator += ch - '0'; + } + state = StateDotDigit; + break; + } + + HandleTwoCharsAndBreak('E', 'e', StateE); + return nan(); + + case StateE: + if (ch == '+') { + exponentSign = Positive; + state = StateESign; + break; + } + + if (ch == '-') { + exponentSign = Negative; + state = StateESign; + break; + } + + if (ch >= '0' && ch <= '9') { + exponent = ch - '0'; + state = StateEDigit; + break; + } + + return nan(); + + case StateEDigit: + if (ch >= '0' && ch <= '9') { + exponent *= 10; + exponent += ch - '0'; + if (exponent > ExponentMax + Precision) { + if (accumulator) + return exponentSign == Negative ? zero(Positive) : infinity(sign); + return zero(sign); + } + state = StateEDigit; + break; + } + + return nan(); + + case StateESign: + if (ch >= '0' && ch <= '9') { + exponent = ch - '0'; + state = StateEDigit; + break; + } + + return nan(); + + case StateSign: + if (ch >= '1' && ch <= '9') { + accumulator = ch - '0'; + numberOfDigits = 1; + state = StateDigit; + break; + } + + HandleCharAndBreak('0', StateZero); + return nan(); + + case StateStart: + if (ch >= '1' && ch <= '9') { + accumulator = ch - '0'; + numberOfDigits = 1; + state = StateDigit; + break; + } + + if (ch == '-') { + sign = Negative; + state = StateSign; + break; + } + + if (ch == '+') { + sign = Positive; + state = StateSign; + break; + } + + HandleCharAndBreak('0', StateZero); + HandleCharAndBreak('.', StateDot); + return nan(); + + case StateZero: + if (ch == '0') + break; + + if (ch >= '1' && ch <= '9') { + accumulator = ch - '0'; + numberOfDigits = 1; + state = StateDigit; + break; + } + + HandleCharAndBreak('.', StateDot); + HandleTwoCharsAndBreak('E', 'e', StateE); + return nan(); + + default: + ASSERT_NOT_REACHED(); + return nan(); + } + } + + if (state == StateZero) + return zero(sign); + + if (state == StateDigit || state == StateEDigit || state == StateDotDigit) { + int resultExponent = exponent * (exponentSign == Negative ? -1 : 1) - numberOfDigitsAfterDot + numberOfExtraDigits; + if (resultExponent < ExponentMin) + return zero(Positive); + + const int overflow = resultExponent - ExponentMax + 1; + if (overflow > 0) { + if (overflow + numberOfDigits - numberOfDigitsAfterDot > Precision) + return infinity(sign); + accumulator = scaleUp(accumulator, overflow); + resultExponent -= overflow; + } + + return Decimal(sign, resultExponent, accumulator); + } + + return nan(); +} + +Decimal Decimal::infinity(const Sign sign) +{ + return Decimal(EncodedData(sign, EncodedData::ClassInfinity)); +} + +Decimal Decimal::nan() +{ + return Decimal(EncodedData(Positive, EncodedData::ClassNaN)); +} + +Decimal Decimal::remainder(const Decimal& rhs) const +{ + const Decimal quotient = *this / rhs; + return quotient.isSpecial() ? quotient : *this - (quotient.isNegative() ? quotient.ceil() : quotient.floor()) * rhs; +} + +Decimal Decimal::round() const +{ + if (isSpecial()) + return *this; + + if (exponent() >= 0) + return *this; + + uint64_t result = m_data.coefficient(); + const int numberOfDigits = countDigits(result); + const int numberOfDropDigits = -exponent(); + if (numberOfDigits < numberOfDropDigits) + return zero(Positive); + + result = scaleDown(result, numberOfDropDigits - 1); + if (result % 10 >= 5) + result += 10; + result /= 10; + return Decimal(sign(), 0, result); +} + +double Decimal::toDouble() const +{ + if (isFinite()) { + bool valid; + const double doubleValue = mozToDouble(toString(), &valid); + return valid ? doubleValue : std::numeric_limits<double>::quiet_NaN(); + } + + if (isInfinity()) + return isNegative() ? -std::numeric_limits<double>::infinity() : std::numeric_limits<double>::infinity(); + + return std::numeric_limits<double>::quiet_NaN(); +} + +String Decimal::toString() const +{ + switch (m_data.formatClass()) { + case EncodedData::ClassInfinity: + return sign() ? "-Infinity" : "Infinity"; + + case EncodedData::ClassNaN: + return "NaN"; + + case EncodedData::ClassNormal: + case EncodedData::ClassZero: + break; + + default: + ASSERT_NOT_REACHED(); + return ""; + } + + StringBuilder builder; + if (sign()) + builder.append('-'); + + int originalExponent = exponent(); + uint64_t coefficient = m_data.coefficient(); + + if (originalExponent < 0) { + const int maxDigits = DBL_DIG; + uint64_t lastDigit = 0; + while (countDigits(coefficient) > maxDigits) { + lastDigit = coefficient % 10; + coefficient /= 10; + ++originalExponent; + } + + if (lastDigit >= 5) + ++coefficient; + + while (originalExponent < 0 && coefficient && !(coefficient % 10)) { + coefficient /= 10; + ++originalExponent; + } + } + + const String digits = mozToString(coefficient); + int coefficientLength = static_cast<int>(digits.length()); + const int adjustedExponent = originalExponent + coefficientLength - 1; + if (originalExponent <= 0 && adjustedExponent >= -6) { + if (!originalExponent) { + builder.append(digits); + return builder.toString(); + } + + if (adjustedExponent >= 0) { + for (int i = 0; i < coefficientLength; ++i) { + builder.append(digits[i]); + if (i == adjustedExponent) + builder.append('.'); + } + return builder.toString(); + } + + builder.appendLiteral("0."); + for (int i = adjustedExponent + 1; i < 0; ++i) + builder.append('0'); + + builder.append(digits); + + } else { + builder.append(digits[0]); + while (coefficientLength >= 2 && digits[coefficientLength - 1] == '0') + --coefficientLength; + if (coefficientLength >= 2) { + builder.append('.'); + for (int i = 1; i < coefficientLength; ++i) + builder.append(digits[i]); + } + + if (adjustedExponent) { + builder.append(adjustedExponent < 0 ? "e" : "e+"); + builder.appendNumber(adjustedExponent); + } + } + return builder.toString(); +} + +bool Decimal::toString(char* strBuf, size_t bufLength) const +{ + ASSERT(bufLength > 0); + String str = toString(); + size_t length = str.copy(strBuf, bufLength); + if (length < bufLength) { + strBuf[length] = '\0'; + return true; + } + strBuf[bufLength - 1] = '\0'; + return false; +} + +Decimal Decimal::zero(Sign sign) +{ + return Decimal(EncodedData(sign, EncodedData::ClassZero)); +} + +} // namespace blink diff --git a/mfbt/decimal/Decimal.h b/mfbt/decimal/Decimal.h new file mode 100644 index 000000000..10d0e2c7c --- /dev/null +++ b/mfbt/decimal/Decimal.h @@ -0,0 +1,221 @@ +/* + * Copyright (C) 2012 Google Inc. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Google Inc. nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +/** + * Imported from: + * https://chromium.googlesource.com/chromium/src.git/+/master/third_party/WebKit/Source/platform/Decimal.h + * Check UPSTREAM-GIT-SHA for the commit ID of the last update from Blink core. + */ + +#ifndef Decimal_h +#define Decimal_h + +#include "mozilla/Assertions.h" +#include <stdint.h> +#include "mozilla/Types.h" + +#include <string> + +#ifndef ASSERT +#define DEFINED_ASSERT_FOR_DECIMAL_H 1 +#define ASSERT MOZ_ASSERT +#endif + +#define PLATFORM_EXPORT + +// To use USING_FAST_MALLOC we'd need: +// https://chromium.googlesource.com/chromium/src.git/+/master/third_party/WebKit/Source/wtf/Allocator.h +// Since we don't allocate Decimal objects, no need. +#define USING_FAST_MALLOC(type) \ + void ignore_this_dummy_method() = delete + +#define DISALLOW_NEW() \ + private: \ + void* operator new(size_t) = delete; \ + void* operator new(size_t, void*) = delete; \ + public: + +namespace blink { + +namespace DecimalPrivate { +class SpecialValueHandler; +} + +// This class represents decimal base floating point number. +// +// FIXME: Once all C++ compiler support decimal type, we should replace this +// class to compiler supported one. See below URI for current status of decimal +// type for C++: // http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2006/n1977.html +class PLATFORM_EXPORT Decimal { + USING_FAST_MALLOC(Decimal); +public: + enum Sign { + Positive, + Negative, + }; + + // You should not use EncodedData other than unit testing. + class EncodedData { + DISALLOW_NEW(); + // For accessing FormatClass. + friend class Decimal; + friend class DecimalPrivate::SpecialValueHandler; + public: + EncodedData(Sign, int exponent, uint64_t coefficient); + + bool operator==(const EncodedData&) const; + bool operator!=(const EncodedData& another) const { return !operator==(another); } + + uint64_t coefficient() const { return m_coefficient; } + int countDigits() const; + int exponent() const { return m_exponent; } + bool isFinite() const { return !isSpecial(); } + bool isInfinity() const { return m_formatClass == ClassInfinity; } + bool isNaN() const { return m_formatClass == ClassNaN; } + bool isSpecial() const { return m_formatClass == ClassInfinity || m_formatClass == ClassNaN; } + bool isZero() const { return m_formatClass == ClassZero; } + Sign sign() const { return m_sign; } + void setSign(Sign sign) { m_sign = sign; } + + private: + enum FormatClass { + ClassInfinity, + ClassNormal, + ClassNaN, + ClassZero, + }; + + EncodedData(Sign, FormatClass); + FormatClass formatClass() const { return m_formatClass; } + + uint64_t m_coefficient; + int16_t m_exponent; + FormatClass m_formatClass; + Sign m_sign; + }; + + MFBT_API explicit Decimal(int32_t = 0); + MFBT_API Decimal(Sign, int exponent, uint64_t coefficient); + MFBT_API Decimal(const Decimal&); + + MFBT_API Decimal& operator=(const Decimal&); + MFBT_API Decimal& operator+=(const Decimal&); + MFBT_API Decimal& operator-=(const Decimal&); + MFBT_API Decimal& operator*=(const Decimal&); + MFBT_API Decimal& operator/=(const Decimal&); + + MFBT_API Decimal operator-() const; + + MFBT_API bool operator==(const Decimal&) const; + MFBT_API bool operator!=(const Decimal&) const; + MFBT_API bool operator<(const Decimal&) const; + MFBT_API bool operator<=(const Decimal&) const; + MFBT_API bool operator>(const Decimal&) const; + MFBT_API bool operator>=(const Decimal&) const; + + MFBT_API Decimal operator+(const Decimal&) const; + MFBT_API Decimal operator-(const Decimal&) const; + MFBT_API Decimal operator*(const Decimal&) const; + MFBT_API Decimal operator/(const Decimal&) const; + + int exponent() const + { + ASSERT(isFinite()); + return m_data.exponent(); + } + + bool isFinite() const { return m_data.isFinite(); } + bool isInfinity() const { return m_data.isInfinity(); } + bool isNaN() const { return m_data.isNaN(); } + bool isNegative() const { return sign() == Negative; } + bool isPositive() const { return sign() == Positive; } + bool isSpecial() const { return m_data.isSpecial(); } + bool isZero() const { return m_data.isZero(); } + + MFBT_API Decimal abs() const; + MFBT_API Decimal ceil() const; + MFBT_API Decimal floor() const; + MFBT_API Decimal remainder(const Decimal&) const; + MFBT_API Decimal round() const; + + MFBT_API double toDouble() const; + // Note: toString method supports infinity and nan but fromString not. + MFBT_API std::string toString() const; + MFBT_API bool toString(char* strBuf, size_t bufLength) const; + + static MFBT_API Decimal fromDouble(double); + // fromString supports following syntax EBNF: + // number ::= sign? digit+ ('.' digit*) (exponent-marker sign? digit+)? + // | sign? '.' digit+ (exponent-marker sign? digit+)? + // sign ::= '+' | '-' + // exponent-marker ::= 'e' | 'E' + // digit ::= '0' | '1' | ... | '9' + // Note: fromString doesn't support "infinity" and "nan". + static MFBT_API Decimal fromString(const std::string& aValue); + static MFBT_API Decimal infinity(Sign); + static MFBT_API Decimal nan(); + static MFBT_API Decimal zero(Sign); + + // You should not use below methods. We expose them for unit testing. + MFBT_API explicit Decimal(const EncodedData&); + const EncodedData& value() const { return m_data; } + +private: + struct AlignedOperands { + uint64_t lhsCoefficient; + uint64_t rhsCoefficient; + int exponent; + }; + + MFBT_API explicit Decimal(double); + MFBT_API Decimal compareTo(const Decimal&) const; + + static MFBT_API AlignedOperands alignOperands(const Decimal& lhs, const Decimal& rhs); + static inline Sign invertSign(Sign sign) { return sign == Negative ? Positive : Negative; } + + Sign sign() const { return m_data.sign(); } + + EncodedData m_data; +}; + +} // namespace blink + +namespace mozilla { +typedef blink::Decimal Decimal; +} // namespace mozilla + +#undef USING_FAST_MALLOC + +#ifdef DEFINED_ASSERT_FOR_DECIMAL_H +#undef DEFINED_ASSERT_FOR_DECIMAL_H +#undef ASSERT +#endif + +#endif // Decimal_h diff --git a/mfbt/decimal/UPSTREAM-GIT-SHA b/mfbt/decimal/UPSTREAM-GIT-SHA new file mode 100644 index 000000000..ed86150b2 --- /dev/null +++ b/mfbt/decimal/UPSTREAM-GIT-SHA @@ -0,0 +1 @@ +cad4c9e3b3c9e80bb189059373db528272bca96f diff --git a/mfbt/decimal/comparison-with-nan.patch b/mfbt/decimal/comparison-with-nan.patch new file mode 100644 index 000000000..477a61437 --- /dev/null +++ b/mfbt/decimal/comparison-with-nan.patch @@ -0,0 +1,67 @@ +diff --git a/mfbt/decimal/Decimal.cpp b/mfbt/decimal/Decimal.cpp +--- a/mfbt/decimal/Decimal.cpp ++++ b/mfbt/decimal/Decimal.cpp +@@ -509,21 +509,25 @@ Decimal Decimal::operator/(const Decimal + if (remainder > divisor / 2) + ++result; + + return Decimal(resultSign, resultExponent, result); + } + + bool Decimal::operator==(const Decimal& rhs) const + { ++ if (isNaN() || rhs.isNaN()) ++ return false; + return m_data == rhs.m_data || compareTo(rhs).isZero(); + } + + bool Decimal::operator!=(const Decimal& rhs) const + { ++ if (isNaN() || rhs.isNaN()) ++ return true; + if (m_data == rhs.m_data) + return false; + const Decimal result = compareTo(rhs); + if (result.isNaN()) + return false; + return !result.isZero(); + } + +@@ -532,16 +536,18 @@ bool Decimal::operator<(const Decimal& r + const Decimal result = compareTo(rhs); + if (result.isNaN()) + return false; + return !result.isZero() && result.isNegative(); + } + + bool Decimal::operator<=(const Decimal& rhs) const + { ++ if (isNaN() || rhs.isNaN()) ++ return false; + if (m_data == rhs.m_data) + return true; + const Decimal result = compareTo(rhs); + if (result.isNaN()) + return false; + return result.isZero() || result.isNegative(); + } + +@@ -550,16 +556,18 @@ bool Decimal::operator>(const Decimal& r + const Decimal result = compareTo(rhs); + if (result.isNaN()) + return false; + return !result.isZero() && result.isPositive(); + } + + bool Decimal::operator>=(const Decimal& rhs) const + { ++ if (isNaN() || rhs.isNaN()) ++ return false; + if (m_data == rhs.m_data) + return true; + const Decimal result = compareTo(rhs); + if (result.isNaN()) + return false; + return result.isZero() || !result.isNegative(); + } + diff --git a/mfbt/decimal/fix-wshadow-warnings.patch b/mfbt/decimal/fix-wshadow-warnings.patch new file mode 100644 index 000000000..eed7b60f7 --- /dev/null +++ b/mfbt/decimal/fix-wshadow-warnings.patch @@ -0,0 +1,171 @@ +diff --git a/mfbt/decimal/Decimal.cpp b/mfbt/decimal/Decimal.cpp +--- a/mfbt/decimal/Decimal.cpp ++++ b/mfbt/decimal/Decimal.cpp +@@ -118,18 +118,18 @@ Decimal SpecialValueHandler::value() con + ASSERT_NOT_REACHED(); + return m_lhs; + } + } + + // This class is used for 128 bit unsigned integer arithmetic. + class UInt128 { + public: +- UInt128(uint64_t low, uint64_t high) +- : m_high(high), m_low(low) ++ UInt128(uint64_t aLow, uint64_t aHigh) ++ : m_high(aHigh), m_low(aLow) + { + } + + UInt128& operator/=(uint32_t); + + uint64_t high() const { return m_high; } + uint64_t low() const { return m_low; } + +@@ -224,68 +224,68 @@ static uint64_t scaleUp(uint64_t x, int + z = z * z; + } + } + + } // namespace DecimalPrivate + + using namespace DecimalPrivate; + +-Decimal::EncodedData::EncodedData(Sign sign, FormatClass formatClass) ++Decimal::EncodedData::EncodedData(Sign aSign, FormatClass aFormatClass) + : m_coefficient(0) + , m_exponent(0) +- , m_formatClass(formatClass) +- , m_sign(sign) ++ , m_formatClass(aFormatClass) ++ , m_sign(aSign) + { + } + +-Decimal::EncodedData::EncodedData(Sign sign, int exponent, uint64_t coefficient) +- : m_formatClass(coefficient ? ClassNormal : ClassZero) +- , m_sign(sign) ++Decimal::EncodedData::EncodedData(Sign aSign, int aExponent, uint64_t aCoefficient) ++ : m_formatClass(aCoefficient ? ClassNormal : ClassZero) ++ , m_sign(aSign) + { +- if (exponent >= ExponentMin && exponent <= ExponentMax) { +- while (coefficient > MaxCoefficient) { +- coefficient /= 10; +- ++exponent; ++ if (aExponent >= ExponentMin && aExponent <= ExponentMax) { ++ while (aCoefficient > MaxCoefficient) { ++ aCoefficient /= 10; ++ ++aExponent; + } + } + +- if (exponent > ExponentMax) { ++ if (aExponent > ExponentMax) { + m_coefficient = 0; + m_exponent = 0; + m_formatClass = ClassInfinity; + return; + } + +- if (exponent < ExponentMin) { ++ if (aExponent < ExponentMin) { + m_coefficient = 0; + m_exponent = 0; + m_formatClass = ClassZero; + return; + } + +- m_coefficient = coefficient; +- m_exponent = static_cast<int16_t>(exponent); ++ m_coefficient = aCoefficient; ++ m_exponent = static_cast<int16_t>(aExponent); + } + + bool Decimal::EncodedData::operator==(const EncodedData& another) const + { + return m_sign == another.m_sign + && m_formatClass == another.m_formatClass + && m_exponent == another.m_exponent + && m_coefficient == another.m_coefficient; + } + + Decimal::Decimal(int32_t i32) + : m_data(i32 < 0 ? Negative : Positive, 0, i32 < 0 ? static_cast<uint64_t>(-static_cast<int64_t>(i32)) : static_cast<uint64_t>(i32)) + { + } + +-Decimal::Decimal(Sign sign, int exponent, uint64_t coefficient) +- : m_data(sign, coefficient ? exponent : 0, coefficient) ++Decimal::Decimal(Sign aSign, int aExponent, uint64_t aCoefficient) ++ : m_data(aSign, aCoefficient ? aExponent : 0, aCoefficient) + { + } + + Decimal::Decimal(const EncodedData& data) + : m_data(data) + { + } + +@@ -479,32 +479,32 @@ Decimal Decimal::operator/(const Decimal + if (rhs.isZero()) + return lhs.isZero() ? nan() : infinity(resultSign); + + int resultExponent = lhs.exponent() - rhs.exponent(); + + if (lhs.isZero()) + return Decimal(resultSign, resultExponent, 0); + +- uint64_t remainder = lhs.m_data.coefficient(); ++ uint64_t lhsRemainder = lhs.m_data.coefficient(); + const uint64_t divisor = rhs.m_data.coefficient(); + uint64_t result = 0; + while (result < MaxCoefficient / 100) { +- while (remainder < divisor) { +- remainder *= 10; ++ while (lhsRemainder < divisor) { ++ lhsRemainder *= 10; + result *= 10; + --resultExponent; + } +- result += remainder / divisor; +- remainder %= divisor; +- if (!remainder) ++ result += lhsRemainder / divisor; ++ lhsRemainder %= divisor; ++ if (!lhsRemainder) + break; + } + +- if (remainder > divisor / 2) ++ if (lhsRemainder > divisor / 2) + ++result; + + return Decimal(resultSign, resultExponent, result); + } + + bool Decimal::operator==(const Decimal& rhs) const + { + if (isNaN() || rhs.isNaN()) +diff --git a/mfbt/decimal/Decimal.h b/mfbt/decimal/Decimal.h +--- a/mfbt/decimal/Decimal.h ++++ b/mfbt/decimal/Decimal.h +@@ -88,17 +88,17 @@ public: + int countDigits() const; + int exponent() const { return m_exponent; } + bool isFinite() const { return !isSpecial(); } + bool isInfinity() const { return m_formatClass == ClassInfinity; } + bool isNaN() const { return m_formatClass == ClassNaN; } + bool isSpecial() const { return m_formatClass == ClassInfinity || m_formatClass == ClassNaN; } + bool isZero() const { return m_formatClass == ClassZero; } + Sign sign() const { return m_sign; } +- void setSign(Sign sign) { m_sign = sign; } ++ void setSign(Sign aSign) { m_sign = aSign; } + + private: + enum FormatClass { + ClassInfinity, + ClassNormal, + ClassNaN, + ClassZero, + }; diff --git a/mfbt/decimal/mfbt-abi-markers.patch b/mfbt/decimal/mfbt-abi-markers.patch new file mode 100644 index 000000000..4399c2134 --- /dev/null +++ b/mfbt/decimal/mfbt-abi-markers.patch @@ -0,0 +1,150 @@ +diff --git a/mfbt/decimal/Decimal.h b/mfbt/decimal/Decimal.h +--- a/mfbt/decimal/Decimal.h ++++ b/mfbt/decimal/Decimal.h +@@ -26,16 +26,18 @@ + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + + #ifndef Decimal_h + #define Decimal_h + ++#include "mozilla/Types.h" ++ + #include "platform/PlatformExport.h" + #include "wtf/Allocator.h" + #include "wtf/Assertions.h" + #include "wtf/text/WTFString.h" + #include <stdint.h> + + namespace blink { + +@@ -91,92 +93,92 @@ public: + FormatClass formatClass() const { return m_formatClass; } + + uint64_t m_coefficient; + int16_t m_exponent; + FormatClass m_formatClass; + Sign m_sign; + }; + +- Decimal(int32_t = 0); +- Decimal(Sign, int exponent, uint64_t coefficient); +- Decimal(const Decimal&); ++ MFBT_API explicit Decimal(int32_t = 0); ++ MFBT_API Decimal(Sign, int exponent, uint64_t coefficient); ++ MFBT_API Decimal(const Decimal&); + +- Decimal& operator=(const Decimal&); +- Decimal& operator+=(const Decimal&); +- Decimal& operator-=(const Decimal&); +- Decimal& operator*=(const Decimal&); +- Decimal& operator/=(const Decimal&); ++ MFBT_API Decimal& operator=(const Decimal&); ++ MFBT_API Decimal& operator+=(const Decimal&); ++ MFBT_API Decimal& operator-=(const Decimal&); ++ MFBT_API Decimal& operator*=(const Decimal&); ++ MFBT_API Decimal& operator/=(const Decimal&); + +- Decimal operator-() const; ++ MFBT_API Decimal operator-() const; + +- bool operator==(const Decimal&) const; +- bool operator!=(const Decimal&) const; +- bool operator<(const Decimal&) const; +- bool operator<=(const Decimal&) const; +- bool operator>(const Decimal&) const; +- bool operator>=(const Decimal&) const; ++ MFBT_API bool operator==(const Decimal&) const; ++ MFBT_API bool operator!=(const Decimal&) const; ++ MFBT_API bool operator<(const Decimal&) const; ++ MFBT_API bool operator<=(const Decimal&) const; ++ MFBT_API bool operator>(const Decimal&) const; ++ MFBT_API bool operator>=(const Decimal&) const; + +- Decimal operator+(const Decimal&) const; +- Decimal operator-(const Decimal&) const; +- Decimal operator*(const Decimal&) const; +- Decimal operator/(const Decimal&) const; ++ MFBT_API Decimal operator+(const Decimal&) const; ++ MFBT_API Decimal operator-(const Decimal&) const; ++ MFBT_API Decimal operator*(const Decimal&) const; ++ MFBT_API Decimal operator/(const Decimal&) const; + + int exponent() const + { + ASSERT(isFinite()); + return m_data.exponent(); + } + + bool isFinite() const { return m_data.isFinite(); } + bool isInfinity() const { return m_data.isInfinity(); } + bool isNaN() const { return m_data.isNaN(); } + bool isNegative() const { return sign() == Negative; } + bool isPositive() const { return sign() == Positive; } + bool isSpecial() const { return m_data.isSpecial(); } + bool isZero() const { return m_data.isZero(); } + +- Decimal abs() const; +- Decimal ceil() const; +- Decimal floor() const; +- Decimal remainder(const Decimal&) const; +- Decimal round() const; ++ MFBT_API Decimal abs() const; ++ MFBT_API Decimal ceil() const; ++ MFBT_API Decimal floor() const; ++ MFBT_API Decimal remainder(const Decimal&) const; ++ MFBT_API Decimal round() const; + +- double toDouble() const; ++ MFBT_API double toDouble() const; + // Note: toString method supports infinity and nan but fromString not. +- String toString() const; ++ MFBT_API String toString() const; + +- static Decimal fromDouble(double); ++ static MFBT_API Decimal fromDouble(double); + // fromString supports following syntax EBNF: + // number ::= sign? digit+ ('.' digit*) (exponent-marker sign? digit+)? + // | sign? '.' digit+ (exponent-marker sign? digit+)? + // sign ::= '+' | '-' + // exponent-marker ::= 'e' | 'E' + // digit ::= '0' | '1' | ... | '9' + // Note: fromString doesn't support "infinity" and "nan". +- static Decimal fromString(const String&); +- static Decimal infinity(Sign); +- static Decimal nan(); +- static Decimal zero(Sign); ++ static MFBT_API Decimal fromString(const String&); ++ static MFBT_API Decimal infinity(Sign); ++ static MFBT_API Decimal nan(); ++ static MFBT_API Decimal zero(Sign); + + // You should not use below methods. We expose them for unit testing. +- explicit Decimal(const EncodedData&); ++ MFBT_API explicit Decimal(const EncodedData&); + const EncodedData& value() const { return m_data; } + + private: + struct AlignedOperands { + uint64_t lhsCoefficient; + uint64_t rhsCoefficient; + int exponent; + }; + +- Decimal(double); +- Decimal compareTo(const Decimal&) const; ++ MFBT_API explicit Decimal(double); ++ MFBT_API Decimal compareTo(const Decimal&) const; + +- static AlignedOperands alignOperands(const Decimal& lhs, const Decimal& rhs); ++ static MFBT_API AlignedOperands alignOperands(const Decimal& lhs, const Decimal& rhs); + static inline Sign invertSign(Sign sign) { return sign == Negative ? Positive : Negative; } + + Sign sign() const { return m_data.sign(); } + + EncodedData m_data; + }; + + } // namespace blink diff --git a/mfbt/decimal/moz-decimal-utils.h b/mfbt/decimal/moz-decimal-utils.h new file mode 100644 index 000000000..f2a9f4f07 --- /dev/null +++ b/mfbt/decimal/moz-decimal-utils.h @@ -0,0 +1,106 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef MOZ_DECIMAL_UTILS_H +#define MOZ_DECIMAL_UTILS_H + +// This file contains extra includes, defines and typedefs to allow compilation +// of Decimal.cpp under the Mozilla source without blink core dependencies. Do +// not include it into any file other than Decimal.cpp. + +#include "../double-conversion/double-conversion.h" +#include "mozilla/ArrayUtils.h" +#include "mozilla/Casting.h" +#include "mozilla/FloatingPoint.h" + +#include <cmath> +#include <cstring> +#include <iomanip> +#include <limits> +#include <sstream> + +#ifndef UINT64_C +// For Android toolchain +#define UINT64_C(c) (c ## ULL) +#endif + +#ifdef ASSERT +#undef ASSERT +#endif +#define ASSERT MOZ_ASSERT + +#define ASSERT_NOT_REACHED() MOZ_ASSERT_UNREACHABLE("moz-decimal-utils.h") + +#define STACK_ALLOCATED() DISALLOW_NEW() + +#define WTF_MAKE_NONCOPYABLE(ClassName) \ + private: \ + ClassName(const ClassName&) = delete; \ + void operator=(const ClassName&) = delete; + +typedef std::string String; + +double mozToDouble(const String &aStr, bool *valid) { + double_conversion::StringToDoubleConverter converter( + double_conversion::StringToDoubleConverter::NO_FLAGS, + mozilla::UnspecifiedNaN<double>(), mozilla::UnspecifiedNaN<double>(), nullptr, nullptr); + const char* str = aStr.c_str(); + int length = mozilla::AssertedCast<int>(strlen(str)); + int processed_char_count; // unused - NO_FLAGS requires the whole string to parse + double result = converter.StringToDouble(str, length, &processed_char_count); + *valid = mozilla::IsFinite(result); + return result; +} + +String mozToString(double aNum) { + char buffer[64]; + int buffer_length = mozilla::ArrayLength(buffer); + const double_conversion::DoubleToStringConverter& converter = + double_conversion::DoubleToStringConverter::EcmaScriptConverter(); + double_conversion::StringBuilder builder(buffer, buffer_length); + converter.ToShortest(aNum, &builder); + return String(builder.Finalize()); +} + +String mozToString(int64_t aNum) { + std::ostringstream o; + o << std::setprecision(std::numeric_limits<int64_t>::digits10) << aNum; + return o.str(); +} + +String mozToString(uint64_t aNum) { + std::ostringstream o; + o << std::setprecision(std::numeric_limits<uint64_t>::digits10) << aNum; + return o.str(); +} + +namespace moz_decimal_utils { + +class StringBuilder +{ +public: + void append(char c) { + mStr += c; + } + void appendLiteral(const char *aStr) { + mStr += aStr; + } + void appendNumber(int aNum) { + mStr += mozToString(int64_t(aNum)); + } + void append(const String& aStr) { + mStr += aStr; + } + std::string toString() const { + return mStr; + } +private: + std::string mStr; +}; + +} // namespace moz_decimal_utils + +#endif + diff --git a/mfbt/decimal/to-moz-dependencies.patch b/mfbt/decimal/to-moz-dependencies.patch new file mode 100644 index 000000000..25f52d7bf --- /dev/null +++ b/mfbt/decimal/to-moz-dependencies.patch @@ -0,0 +1,224 @@ +diff --git a/mfbt/decimal/Decimal.cpp b/mfbt/decimal/Decimal.cpp +--- a/mfbt/decimal/Decimal.cpp ++++ b/mfbt/decimal/Decimal.cpp +@@ -23,22 +23,20 @@ + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +-#include "platform/Decimal.h" ++#include "Decimal.h" ++#include "moz-decimal-utils.h" + +-#include "wtf/Allocator.h" +-#include "wtf/MathExtras.h" +-#include "wtf/Noncopyable.h" +-#include "wtf/text/StringBuilder.h" ++using namespace moz_decimal_utils; + + #include <algorithm> + #include <float.h> + + namespace blink { + + namespace DecimalPrivate { + +@@ -690,17 +688,17 @@ Decimal Decimal::floor() const + if (isNegative() && !isMultiplePowersOfTen(m_data.coefficient(), numberOfDropDigits)) + ++result; + return Decimal(sign(), 0, result); + } + + Decimal Decimal::fromDouble(double doubleValue) + { + if (std::isfinite(doubleValue)) +- return fromString(String::numberToStringECMAScript(doubleValue)); ++ return fromString(mozToString(doubleValue)); + + if (std::isinf(doubleValue)) + return infinity(doubleValue < 0 ? Negative : Positive); + + return nan(); + } + + Decimal Decimal::fromString(const String& str) +@@ -931,17 +929,17 @@ Decimal Decimal::round() const + result /= 10; + return Decimal(sign(), 0, result); + } + + double Decimal::toDouble() const + { + if (isFinite()) { + bool valid; +- const double doubleValue = toString().toDouble(&valid); ++ const double doubleValue = mozToDouble(toString(), &valid); + return valid ? doubleValue : std::numeric_limits<double>::quiet_NaN(); + } + + if (isInfinity()) + return isNegative() ? -std::numeric_limits<double>::infinity() : std::numeric_limits<double>::infinity(); + + return std::numeric_limits<double>::quiet_NaN(); + } +@@ -984,17 +982,17 @@ String Decimal::toString() const + ++coefficient; + + while (originalExponent < 0 && coefficient && !(coefficient % 10)) { + coefficient /= 10; + ++originalExponent; + } + } + +- const String digits = String::number(coefficient); ++ const String digits = mozToString(coefficient); + int coefficientLength = static_cast<int>(digits.length()); + const int adjustedExponent = originalExponent + coefficientLength - 1; + if (originalExponent <= 0 && adjustedExponent >= -6) { + if (!originalExponent) { + builder.append(digits); + return builder.toString(); + } + +@@ -1026,14 +1024,27 @@ String Decimal::toString() const + if (adjustedExponent) { + builder.append(adjustedExponent < 0 ? "e" : "e+"); + builder.appendNumber(adjustedExponent); + } + } + return builder.toString(); + } + ++bool Decimal::toString(char* strBuf, size_t bufLength) const ++{ ++ ASSERT(bufLength > 0); ++ String str = toString(); ++ size_t length = str.copy(strBuf, bufLength); ++ if (length < bufLength) { ++ strBuf[length] = '\0'; ++ return true; ++ } ++ strBuf[bufLength - 1] = '\0'; ++ return false; ++} ++ + Decimal Decimal::zero(Sign sign) + { + return Decimal(EncodedData(sign, EncodedData::ClassZero)); + } + + } // namespace blink +diff --git a/mfbt/decimal/Decimal.h b/mfbt/decimal/Decimal.h +--- a/mfbt/decimal/Decimal.h ++++ b/mfbt/decimal/Decimal.h +@@ -23,26 +23,49 @@ + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + ++/** ++ * Imported from: ++ * https://chromium.googlesource.com/chromium/src.git/+/master/third_party/WebKit/Source/platform/Decimal.h ++ * Check UPSTREAM-GIT-SHA for the commit ID of the last update from Blink core. ++ */ ++ + #ifndef Decimal_h + #define Decimal_h + ++#include "mozilla/Assertions.h" ++#include <stdint.h> + #include "mozilla/Types.h" + +-#include "platform/PlatformExport.h" +-#include "wtf/Allocator.h" +-#include "wtf/Assertions.h" +-#include "wtf/text/WTFString.h" +-#include <stdint.h> ++#include <string> ++ ++#ifndef ASSERT ++#define DEFINED_ASSERT_FOR_DECIMAL_H 1 ++#define ASSERT MOZ_ASSERT ++#endif ++ ++#define PLATFORM_EXPORT ++ ++// To use USING_FAST_MALLOC we'd need: ++// https://chromium.googlesource.com/chromium/src.git/+/master/third_party/WebKit/Source/wtf/Allocator.h ++// Since we don't allocate Decimal objects, no need. ++#define USING_FAST_MALLOC(type) \ ++ void ignore_this_dummy_method() = delete ++ ++#define DISALLOW_NEW() \ ++ private: \ ++ void* operator new(size_t) = delete; \ ++ void* operator new(size_t, void*) = delete; \ ++ public: + + namespace blink { + + namespace DecimalPrivate { + class SpecialValueHandler; + } + + // This class represents decimal base floating point number. +@@ -139,27 +162,28 @@ public: + MFBT_API Decimal abs() const; + MFBT_API Decimal ceil() const; + MFBT_API Decimal floor() const; + MFBT_API Decimal remainder(const Decimal&) const; + MFBT_API Decimal round() const; + + MFBT_API double toDouble() const; + // Note: toString method supports infinity and nan but fromString not. +- MFBT_API String toString() const; ++ MFBT_API std::string toString() const; ++ MFBT_API bool toString(char* strBuf, size_t bufLength) const; + + static MFBT_API Decimal fromDouble(double); + // fromString supports following syntax EBNF: + // number ::= sign? digit+ ('.' digit*) (exponent-marker sign? digit+)? + // | sign? '.' digit+ (exponent-marker sign? digit+)? + // sign ::= '+' | '-' + // exponent-marker ::= 'e' | 'E' + // digit ::= '0' | '1' | ... | '9' + // Note: fromString doesn't support "infinity" and "nan". +- static MFBT_API Decimal fromString(const String&); ++ static MFBT_API Decimal fromString(const std::string& aValue); + static MFBT_API Decimal infinity(Sign); + static MFBT_API Decimal nan(); + static MFBT_API Decimal zero(Sign); + + // You should not use below methods. We expose them for unit testing. + MFBT_API explicit Decimal(const EncodedData&); + const EncodedData& value() const { return m_data; } + +@@ -178,9 +202,20 @@ private: + + Sign sign() const { return m_data.sign(); } + + EncodedData m_data; + }; + + } // namespace blink + ++namespace mozilla { ++typedef blink::Decimal Decimal; ++} // namespace mozilla ++ ++#undef USING_FAST_MALLOC ++ ++#ifdef DEFINED_ASSERT_FOR_DECIMAL_H ++#undef DEFINED_ASSERT_FOR_DECIMAL_H ++#undef ASSERT ++#endif ++ + #endif // Decimal_h diff --git a/mfbt/decimal/update.sh b/mfbt/decimal/update.sh new file mode 100755 index 000000000..59e626f87 --- /dev/null +++ b/mfbt/decimal/update.sh @@ -0,0 +1,58 @@ +# Usage: ./update.sh [blink-core-source-directory] +# +# Copies the needed files from a directory containing the original +# Decimal.h and Decimal.cpp source that we need. +# If [blink-core-source-directory] is not specified, this script will +# attempt to download the latest versions using git. + +set -e + +FILES=( + "Decimal.h" + "Decimal.cpp" +) + +OWN_NAME=`basename $0` + +if [ $# -gt 1 ]; then + echo "$OWN_NAME: Too many arguments">&2 + exit 1 +fi + +if [ $# -eq 1 ]; then + BLINK_CORE_DIR="$1" + for F in "${FILES[@]}" + do + P="$BLINK_CORE_DIR/$F" + if [ ! -f "$P" ]; then + echo "$OWN_NAME: Couldn't find file: $P">&2 + exit 1 + fi + done + for F in "${FILES[@]}" + do + P="$BLINK_CORE_DIR/$F" + cp "$P" . + done +else + LATEST_SHA=$(git ls-remote https://chromium.googlesource.com/chromium/src.git/ | awk "/refs\/heads\/master/ {print \$1}") + REPO_PATH="https://chromium.googlesource.com/chromium/src.git/+/$LATEST_SHA/third_party/WebKit/Source/platform" + #REPO_PATH="https://github.com/WebKit/webkit/tree/master/Source/WebCore/platform" + for F in "${FILES[@]}" + do + printf "Downloading `basename $F`..." + curl "$REPO_PATH/${F}?format=TEXT" | base64 -D > "$F" + echo done. + done + echo $LATEST_SHA > UPSTREAM-GIT-SHA +fi + +# Apply patches: + +patch -p3 < zero-serialization.patch +patch -p3 < comparison-with-nan.patch +patch -p3 < mfbt-abi-markers.patch +patch -p3 < to-moz-dependencies.patch +# The following is disabled. See +# https://bugzilla.mozilla.org/show_bug.cgi?id=1208357#c7 +#patch -p3 < fix-wshadow-warnings.patch diff --git a/mfbt/decimal/zero-serialization.patch b/mfbt/decimal/zero-serialization.patch new file mode 100644 index 000000000..bafa35956 --- /dev/null +++ b/mfbt/decimal/zero-serialization.patch @@ -0,0 +1,22 @@ +diff --git a/mfbt/decimal/Decimal.cpp b/mfbt/decimal/Decimal.cpp +--- a/mfbt/decimal/Decimal.cpp ++++ b/mfbt/decimal/Decimal.cpp +@@ -277,17 +277,17 @@ bool Decimal::EncodedData::operator==(co + } + + Decimal::Decimal(int32_t i32) + : m_data(i32 < 0 ? Negative : Positive, 0, i32 < 0 ? static_cast<uint64_t>(-static_cast<int64_t>(i32)) : static_cast<uint64_t>(i32)) + { + } + + Decimal::Decimal(Sign sign, int exponent, uint64_t coefficient) +- : m_data(sign, exponent, coefficient) ++ : m_data(sign, coefficient ? exponent : 0, coefficient) + { + } + + Decimal::Decimal(const EncodedData& data) + : m_data(data) + { + } + diff --git a/mfbt/double-conversion/LICENSE b/mfbt/double-conversion/LICENSE new file mode 100644 index 000000000..933718a9e --- /dev/null +++ b/mfbt/double-conversion/LICENSE @@ -0,0 +1,26 @@ +Copyright 2006-2011, the V8 project authors. All rights reserved. +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are +met: + + * Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above + copyright notice, this list of conditions and the following + disclaimer in the documentation and/or other materials provided + with the distribution. + * Neither the name of Google Inc. nor the names of its + contributors may be used to endorse or promote products derived + from this software without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. diff --git a/mfbt/double-conversion/README b/mfbt/double-conversion/README new file mode 100644 index 000000000..f186b420f --- /dev/null +++ b/mfbt/double-conversion/README @@ -0,0 +1,11 @@ +http://code.google.com/p/double-conversion + +This project (double-conversion) provides binary-decimal and decimal-binary +routines for IEEE doubles. + +The library consists of efficient conversion routines that have been extracted +from the V8 JavaScript engine. The code has been refactored and improved so that +it can be used more easily in other projects. + +There is extensive documentation in src/double-conversion.h. Other examples can +be found in test/cctest/test-conversions.cc. diff --git a/mfbt/double-conversion/ToPrecision-exponential.patch b/mfbt/double-conversion/ToPrecision-exponential.patch new file mode 100644 index 000000000..202b29b1b --- /dev/null +++ b/mfbt/double-conversion/ToPrecision-exponential.patch @@ -0,0 +1,35 @@ +1e7bf0c636b8cca54dd83456a0f8fa219343e2a1 Bug 608195 - part 2 - extend ToPrecision to tell use whether exponential notation was used +diff --git a/mfbt/double-conversion/double-conversion.cc b/mfbt/double-conversion/double-conversion.cc +index febba6c..394b6a0 100644 +--- a/mfbt/double-conversion/double-conversion.cc ++++ b/mfbt/double-conversion/double-conversion.cc +@@ -283,7 +283,9 @@ bool DoubleToStringConverter::ToExponential( + + bool DoubleToStringConverter::ToPrecision(double value, + int precision, ++ bool* used_exponential_notation, + StringBuilder* result_builder) const { ++ *used_exponential_notation = false; + if (Double(value).IsSpecial()) { + return HandleSpecialValues(value, result_builder); + } +@@ -325,6 +327,7 @@ bool DoubleToStringConverter::ToPrecision(double value, + decimal_rep[i] = '0'; + } + ++ *used_exponential_notation = true; + CreateExponentialRepresentation(decimal_rep, + precision, + exponent, +diff --git a/mfbt/double-conversion/double-conversion.h b/mfbt/double-conversion/double-conversion.h +index 0900ba0..957575c 100644 +--- a/mfbt/double-conversion/double-conversion.h ++++ b/mfbt/double-conversion/double-conversion.h +@@ -270,6 +270,7 @@ class DoubleToStringConverter { + // exponent character, the exponent's sign, and at most 3 exponent digits). + MFBT_API bool ToPrecision(double value, + int precision, ++ bool* used_exponential_notation, + StringBuilder* result_builder) const; + + enum DtoaMode { diff --git a/mfbt/double-conversion/add-mfbt-api-markers.patch b/mfbt/double-conversion/add-mfbt-api-markers.patch new file mode 100644 index 000000000..bbb50f6f5 --- /dev/null +++ b/mfbt/double-conversion/add-mfbt-api-markers.patch @@ -0,0 +1,94 @@ +diff --git a/mfbt/double-conversion/double-conversion.h b/mfbt/double-conversion/double-conversion.h +index f98edae..c62b16b 100644 +--- a/mfbt/double-conversion/double-conversion.h ++++ b/mfbt/double-conversion/double-conversion.h +@@ -28,6 +28,7 @@ + #ifndef DOUBLE_CONVERSION_DOUBLE_CONVERSION_H_ + #define DOUBLE_CONVERSION_DOUBLE_CONVERSION_H_ + ++#include "mozilla/Types.h" + #include "utils.h" + + namespace double_conversion { +@@ -129,7 +130,7 @@ class DoubleToStringConverter { + } + + // Returns a converter following the EcmaScript specification. +- static const DoubleToStringConverter& EcmaScriptConverter(); ++ static MFBT_API const DoubleToStringConverter& EcmaScriptConverter(); + + // Computes the shortest string of digits that correctly represent the input + // number. Depending on decimal_in_shortest_low and decimal_in_shortest_high +@@ -197,7 +198,7 @@ class DoubleToStringConverter { + // The last two conditions imply that the result will never contain more than + // 1 + kMaxFixedDigitsBeforePoint + 1 + kMaxFixedDigitsAfterPoint characters + // (one additional character for the sign, and one for the decimal point). +- bool ToFixed(double value, ++ MFBT_API bool ToFixed(double value, + int requested_digits, + StringBuilder* result_builder) const; + +@@ -229,7 +230,7 @@ class DoubleToStringConverter { + // kMaxExponentialDigits + 8 characters (the sign, the digit before the + // decimal point, the decimal point, the exponent character, the + // exponent's sign, and at most 3 exponent digits). +- bool ToExponential(double value, ++ MFBT_API bool ToExponential(double value, + int requested_digits, + StringBuilder* result_builder) const; + +@@ -267,7 +268,7 @@ class DoubleToStringConverter { + // The last condition implies that the result will never contain more than + // kMaxPrecisionDigits + 7 characters (the sign, the decimal point, the + // exponent character, the exponent's sign, and at most 3 exponent digits). +- bool ToPrecision(double value, ++ MFBT_API bool ToPrecision(double value, + int precision, + StringBuilder* result_builder) const; + +@@ -292,7 +293,7 @@ class DoubleToStringConverter { + // kBase10MaximalLength. + // Note that DoubleToAscii null-terminates its input. So the given buffer + // should be at least kBase10MaximalLength + 1 characters long. +- static const int kBase10MaximalLength = 17; ++ static const MFBT_DATA int kBase10MaximalLength = 17; + + // Converts the given double 'v' to ascii. 'v' must not be NaN, +Infinity, or + // -Infinity. In SHORTEST_SINGLE-mode this restriction also applies to 'v' +@@ -332,7 +333,7 @@ class DoubleToStringConverter { + // terminating null-character when computing the maximal output size. + // The given length is only used in debug mode to ensure the buffer is big + // enough. +- static void DoubleToAscii(double v, ++ static MFBT_API void DoubleToAscii(double v, + DtoaMode mode, + int requested_digits, + char* buffer, +@@ -343,7 +344,7 @@ class DoubleToStringConverter { + + private: + // Implementation for ToShortest and ToShortestSingle. +- bool ToShortestIeeeNumber(double value, ++ MFBT_API bool ToShortestIeeeNumber(double value, + StringBuilder* result_builder, + DtoaMode mode) const; + +@@ -351,15 +352,15 @@ class DoubleToStringConverter { + // corresponding string using the configured infinity/nan-symbol. + // If either of them is NULL or the value is not special then the + // function returns false. +- bool HandleSpecialValues(double value, StringBuilder* result_builder) const; ++ MFBT_API bool HandleSpecialValues(double value, StringBuilder* result_builder) const; + // Constructs an exponential representation (i.e. 1.234e56). + // The given exponent assumes a decimal point after the first decimal digit. +- void CreateExponentialRepresentation(const char* decimal_digits, ++ MFBT_API void CreateExponentialRepresentation(const char* decimal_digits, + int length, + int exponent, + StringBuilder* result_builder) const; + // Creates a decimal representation (i.e 1234.5678). +- void CreateDecimalRepresentation(const char* decimal_digits, ++ MFBT_API void CreateDecimalRepresentation(const char* decimal_digits, + int length, + int decimal_point, + int digits_after_point, diff --git a/mfbt/double-conversion/bignum-dtoa.cc b/mfbt/double-conversion/bignum-dtoa.cc new file mode 100644 index 000000000..b6c2e85d1 --- /dev/null +++ b/mfbt/double-conversion/bignum-dtoa.cc @@ -0,0 +1,640 @@ +// Copyright 2010 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#include <math.h> + +#include "bignum-dtoa.h" + +#include "bignum.h" +#include "ieee.h" + +namespace double_conversion { + +static int NormalizedExponent(uint64_t significand, int exponent) { + ASSERT(significand != 0); + while ((significand & Double::kHiddenBit) == 0) { + significand = significand << 1; + exponent = exponent - 1; + } + return exponent; +} + + +// Forward declarations: +// Returns an estimation of k such that 10^(k-1) <= v < 10^k. +static int EstimatePower(int exponent); +// Computes v / 10^estimated_power exactly, as a ratio of two bignums, numerator +// and denominator. +static void InitialScaledStartValues(uint64_t significand, + int exponent, + bool lower_boundary_is_closer, + int estimated_power, + bool need_boundary_deltas, + Bignum* numerator, + Bignum* denominator, + Bignum* delta_minus, + Bignum* delta_plus); +// Multiplies numerator/denominator so that its values lies in the range 1-10. +// Returns decimal_point s.t. +// v = numerator'/denominator' * 10^(decimal_point-1) +// where numerator' and denominator' are the values of numerator and +// denominator after the call to this function. +static void FixupMultiply10(int estimated_power, bool is_even, + int* decimal_point, + Bignum* numerator, Bignum* denominator, + Bignum* delta_minus, Bignum* delta_plus); +// Generates digits from the left to the right and stops when the generated +// digits yield the shortest decimal representation of v. +static void GenerateShortestDigits(Bignum* numerator, Bignum* denominator, + Bignum* delta_minus, Bignum* delta_plus, + bool is_even, + Vector<char> buffer, int* length); +// Generates 'requested_digits' after the decimal point. +static void BignumToFixed(int requested_digits, int* decimal_point, + Bignum* numerator, Bignum* denominator, + Vector<char>(buffer), int* length); +// Generates 'count' digits of numerator/denominator. +// Once 'count' digits have been produced rounds the result depending on the +// remainder (remainders of exactly .5 round upwards). Might update the +// decimal_point when rounding up (for example for 0.9999). +static void GenerateCountedDigits(int count, int* decimal_point, + Bignum* numerator, Bignum* denominator, + Vector<char>(buffer), int* length); + + +void BignumDtoa(double v, BignumDtoaMode mode, int requested_digits, + Vector<char> buffer, int* length, int* decimal_point) { + ASSERT(v > 0); + ASSERT(!Double(v).IsSpecial()); + uint64_t significand; + int exponent; + bool lower_boundary_is_closer; + if (mode == BIGNUM_DTOA_SHORTEST_SINGLE) { + float f = static_cast<float>(v); + ASSERT(f == v); + significand = Single(f).Significand(); + exponent = Single(f).Exponent(); + lower_boundary_is_closer = Single(f).LowerBoundaryIsCloser(); + } else { + significand = Double(v).Significand(); + exponent = Double(v).Exponent(); + lower_boundary_is_closer = Double(v).LowerBoundaryIsCloser(); + } + bool need_boundary_deltas = + (mode == BIGNUM_DTOA_SHORTEST || mode == BIGNUM_DTOA_SHORTEST_SINGLE); + + bool is_even = (significand & 1) == 0; + int normalized_exponent = NormalizedExponent(significand, exponent); + // estimated_power might be too low by 1. + int estimated_power = EstimatePower(normalized_exponent); + + // Shortcut for Fixed. + // The requested digits correspond to the digits after the point. If the + // number is much too small, then there is no need in trying to get any + // digits. + if (mode == BIGNUM_DTOA_FIXED && -estimated_power - 1 > requested_digits) { + buffer[0] = '\0'; + *length = 0; + // Set decimal-point to -requested_digits. This is what Gay does. + // Note that it should not have any effect anyways since the string is + // empty. + *decimal_point = -requested_digits; + return; + } + + Bignum numerator; + Bignum denominator; + Bignum delta_minus; + Bignum delta_plus; + // Make sure the bignum can grow large enough. The smallest double equals + // 4e-324. In this case the denominator needs fewer than 324*4 binary digits. + // The maximum double is 1.7976931348623157e308 which needs fewer than + // 308*4 binary digits. + ASSERT(Bignum::kMaxSignificantBits >= 324*4); + InitialScaledStartValues(significand, exponent, lower_boundary_is_closer, + estimated_power, need_boundary_deltas, + &numerator, &denominator, + &delta_minus, &delta_plus); + // We now have v = (numerator / denominator) * 10^estimated_power. + FixupMultiply10(estimated_power, is_even, decimal_point, + &numerator, &denominator, + &delta_minus, &delta_plus); + // We now have v = (numerator / denominator) * 10^(decimal_point-1), and + // 1 <= (numerator + delta_plus) / denominator < 10 + switch (mode) { + case BIGNUM_DTOA_SHORTEST: + case BIGNUM_DTOA_SHORTEST_SINGLE: + GenerateShortestDigits(&numerator, &denominator, + &delta_minus, &delta_plus, + is_even, buffer, length); + break; + case BIGNUM_DTOA_FIXED: + BignumToFixed(requested_digits, decimal_point, + &numerator, &denominator, + buffer, length); + break; + case BIGNUM_DTOA_PRECISION: + GenerateCountedDigits(requested_digits, decimal_point, + &numerator, &denominator, + buffer, length); + break; + default: + UNREACHABLE(); + } + buffer[*length] = '\0'; +} + + +// The procedure starts generating digits from the left to the right and stops +// when the generated digits yield the shortest decimal representation of v. A +// decimal representation of v is a number lying closer to v than to any other +// double, so it converts to v when read. +// +// This is true if d, the decimal representation, is between m- and m+, the +// upper and lower boundaries. d must be strictly between them if !is_even. +// m- := (numerator - delta_minus) / denominator +// m+ := (numerator + delta_plus) / denominator +// +// Precondition: 0 <= (numerator+delta_plus) / denominator < 10. +// If 1 <= (numerator+delta_plus) / denominator < 10 then no leading 0 digit +// will be produced. This should be the standard precondition. +static void GenerateShortestDigits(Bignum* numerator, Bignum* denominator, + Bignum* delta_minus, Bignum* delta_plus, + bool is_even, + Vector<char> buffer, int* length) { + // Small optimization: if delta_minus and delta_plus are the same just reuse + // one of the two bignums. + if (Bignum::Equal(*delta_minus, *delta_plus)) { + delta_plus = delta_minus; + } + *length = 0; + while (true) { + uint16_t digit; + digit = numerator->DivideModuloIntBignum(*denominator); + ASSERT(digit <= 9); // digit is a uint16_t and therefore always positive. + // digit = numerator / denominator (integer division). + // numerator = numerator % denominator. + buffer[(*length)++] = digit + '0'; + + // Can we stop already? + // If the remainder of the division is less than the distance to the lower + // boundary we can stop. In this case we simply round down (discarding the + // remainder). + // Similarly we test if we can round up (using the upper boundary). + bool in_delta_room_minus; + bool in_delta_room_plus; + if (is_even) { + in_delta_room_minus = Bignum::LessEqual(*numerator, *delta_minus); + } else { + in_delta_room_minus = Bignum::Less(*numerator, *delta_minus); + } + if (is_even) { + in_delta_room_plus = + Bignum::PlusCompare(*numerator, *delta_plus, *denominator) >= 0; + } else { + in_delta_room_plus = + Bignum::PlusCompare(*numerator, *delta_plus, *denominator) > 0; + } + if (!in_delta_room_minus && !in_delta_room_plus) { + // Prepare for next iteration. + numerator->Times10(); + delta_minus->Times10(); + // We optimized delta_plus to be equal to delta_minus (if they share the + // same value). So don't multiply delta_plus if they point to the same + // object. + if (delta_minus != delta_plus) { + delta_plus->Times10(); + } + } else if (in_delta_room_minus && in_delta_room_plus) { + // Let's see if 2*numerator < denominator. + // If yes, then the next digit would be < 5 and we can round down. + int compare = Bignum::PlusCompare(*numerator, *numerator, *denominator); + if (compare < 0) { + // Remaining digits are less than .5. -> Round down (== do nothing). + } else if (compare > 0) { + // Remaining digits are more than .5 of denominator. -> Round up. + // Note that the last digit could not be a '9' as otherwise the whole + // loop would have stopped earlier. + // We still have an assert here in case the preconditions were not + // satisfied. + ASSERT(buffer[(*length) - 1] != '9'); + buffer[(*length) - 1]++; + } else { + // Halfway case. + // TODO(floitsch): need a way to solve half-way cases. + // For now let's round towards even (since this is what Gay seems to + // do). + + if ((buffer[(*length) - 1] - '0') % 2 == 0) { + // Round down => Do nothing. + } else { + ASSERT(buffer[(*length) - 1] != '9'); + buffer[(*length) - 1]++; + } + } + return; + } else if (in_delta_room_minus) { + // Round down (== do nothing). + return; + } else { // in_delta_room_plus + // Round up. + // Note again that the last digit could not be '9' since this would have + // stopped the loop earlier. + // We still have an ASSERT here, in case the preconditions were not + // satisfied. + ASSERT(buffer[(*length) -1] != '9'); + buffer[(*length) - 1]++; + return; + } + } +} + + +// Let v = numerator / denominator < 10. +// Then we generate 'count' digits of d = x.xxxxx... (without the decimal point) +// from left to right. Once 'count' digits have been produced we decide wether +// to round up or down. Remainders of exactly .5 round upwards. Numbers such +// as 9.999999 propagate a carry all the way, and change the +// exponent (decimal_point), when rounding upwards. +static void GenerateCountedDigits(int count, int* decimal_point, + Bignum* numerator, Bignum* denominator, + Vector<char>(buffer), int* length) { + ASSERT(count >= 0); + for (int i = 0; i < count - 1; ++i) { + uint16_t digit; + digit = numerator->DivideModuloIntBignum(*denominator); + ASSERT(digit <= 9); // digit is a uint16_t and therefore always positive. + // digit = numerator / denominator (integer division). + // numerator = numerator % denominator. + buffer[i] = digit + '0'; + // Prepare for next iteration. + numerator->Times10(); + } + // Generate the last digit. + uint16_t digit; + digit = numerator->DivideModuloIntBignum(*denominator); + if (Bignum::PlusCompare(*numerator, *numerator, *denominator) >= 0) { + digit++; + } + buffer[count - 1] = digit + '0'; + // Correct bad digits (in case we had a sequence of '9's). Propagate the + // carry until we hat a non-'9' or til we reach the first digit. + for (int i = count - 1; i > 0; --i) { + if (buffer[i] != '0' + 10) break; + buffer[i] = '0'; + buffer[i - 1]++; + } + if (buffer[0] == '0' + 10) { + // Propagate a carry past the top place. + buffer[0] = '1'; + (*decimal_point)++; + } + *length = count; +} + + +// Generates 'requested_digits' after the decimal point. It might omit +// trailing '0's. If the input number is too small then no digits at all are +// generated (ex.: 2 fixed digits for 0.00001). +// +// Input verifies: 1 <= (numerator + delta) / denominator < 10. +static void BignumToFixed(int requested_digits, int* decimal_point, + Bignum* numerator, Bignum* denominator, + Vector<char>(buffer), int* length) { + // Note that we have to look at more than just the requested_digits, since + // a number could be rounded up. Example: v=0.5 with requested_digits=0. + // Even though the power of v equals 0 we can't just stop here. + if (-(*decimal_point) > requested_digits) { + // The number is definitively too small. + // Ex: 0.001 with requested_digits == 1. + // Set decimal-point to -requested_digits. This is what Gay does. + // Note that it should not have any effect anyways since the string is + // empty. + *decimal_point = -requested_digits; + *length = 0; + return; + } else if (-(*decimal_point) == requested_digits) { + // We only need to verify if the number rounds down or up. + // Ex: 0.04 and 0.06 with requested_digits == 1. + ASSERT(*decimal_point == -requested_digits); + // Initially the fraction lies in range (1, 10]. Multiply the denominator + // by 10 so that we can compare more easily. + denominator->Times10(); + if (Bignum::PlusCompare(*numerator, *numerator, *denominator) >= 0) { + // If the fraction is >= 0.5 then we have to include the rounded + // digit. + buffer[0] = '1'; + *length = 1; + (*decimal_point)++; + } else { + // Note that we caught most of similar cases earlier. + *length = 0; + } + return; + } else { + // The requested digits correspond to the digits after the point. + // The variable 'needed_digits' includes the digits before the point. + int needed_digits = (*decimal_point) + requested_digits; + GenerateCountedDigits(needed_digits, decimal_point, + numerator, denominator, + buffer, length); + } +} + + +// Returns an estimation of k such that 10^(k-1) <= v < 10^k where +// v = f * 2^exponent and 2^52 <= f < 2^53. +// v is hence a normalized double with the given exponent. The output is an +// approximation for the exponent of the decimal approimation .digits * 10^k. +// +// The result might undershoot by 1 in which case 10^k <= v < 10^k+1. +// Note: this property holds for v's upper boundary m+ too. +// 10^k <= m+ < 10^k+1. +// (see explanation below). +// +// Examples: +// EstimatePower(0) => 16 +// EstimatePower(-52) => 0 +// +// Note: e >= 0 => EstimatedPower(e) > 0. No similar claim can be made for e<0. +static int EstimatePower(int exponent) { + // This function estimates log10 of v where v = f*2^e (with e == exponent). + // Note that 10^floor(log10(v)) <= v, but v <= 10^ceil(log10(v)). + // Note that f is bounded by its container size. Let p = 53 (the double's + // significand size). Then 2^(p-1) <= f < 2^p. + // + // Given that log10(v) == log2(v)/log2(10) and e+(len(f)-1) is quite close + // to log2(v) the function is simplified to (e+(len(f)-1)/log2(10)). + // The computed number undershoots by less than 0.631 (when we compute log3 + // and not log10). + // + // Optimization: since we only need an approximated result this computation + // can be performed on 64 bit integers. On x86/x64 architecture the speedup is + // not really measurable, though. + // + // Since we want to avoid overshooting we decrement by 1e10 so that + // floating-point imprecisions don't affect us. + // + // Explanation for v's boundary m+: the computation takes advantage of + // the fact that 2^(p-1) <= f < 2^p. Boundaries still satisfy this requirement + // (even for denormals where the delta can be much more important). + + const double k1Log10 = 0.30102999566398114; // 1/lg(10) + + // For doubles len(f) == 53 (don't forget the hidden bit). + const int kSignificandSize = Double::kSignificandSize; + double estimate = ceil((exponent + kSignificandSize - 1) * k1Log10 - 1e-10); + return static_cast<int>(estimate); +} + + +// See comments for InitialScaledStartValues. +static void InitialScaledStartValuesPositiveExponent( + uint64_t significand, int exponent, + int estimated_power, bool need_boundary_deltas, + Bignum* numerator, Bignum* denominator, + Bignum* delta_minus, Bignum* delta_plus) { + // A positive exponent implies a positive power. + ASSERT(estimated_power >= 0); + // Since the estimated_power is positive we simply multiply the denominator + // by 10^estimated_power. + + // numerator = v. + numerator->AssignUInt64(significand); + numerator->ShiftLeft(exponent); + // denominator = 10^estimated_power. + denominator->AssignPowerUInt16(10, estimated_power); + + if (need_boundary_deltas) { + // Introduce a common denominator so that the deltas to the boundaries are + // integers. + denominator->ShiftLeft(1); + numerator->ShiftLeft(1); + // Let v = f * 2^e, then m+ - v = 1/2 * 2^e; With the common + // denominator (of 2) delta_plus equals 2^e. + delta_plus->AssignUInt16(1); + delta_plus->ShiftLeft(exponent); + // Same for delta_minus. The adjustments if f == 2^p-1 are done later. + delta_minus->AssignUInt16(1); + delta_minus->ShiftLeft(exponent); + } +} + + +// See comments for InitialScaledStartValues +static void InitialScaledStartValuesNegativeExponentPositivePower( + uint64_t significand, int exponent, + int estimated_power, bool need_boundary_deltas, + Bignum* numerator, Bignum* denominator, + Bignum* delta_minus, Bignum* delta_plus) { + // v = f * 2^e with e < 0, and with estimated_power >= 0. + // This means that e is close to 0 (have a look at how estimated_power is + // computed). + + // numerator = significand + // since v = significand * 2^exponent this is equivalent to + // numerator = v * / 2^-exponent + numerator->AssignUInt64(significand); + // denominator = 10^estimated_power * 2^-exponent (with exponent < 0) + denominator->AssignPowerUInt16(10, estimated_power); + denominator->ShiftLeft(-exponent); + + if (need_boundary_deltas) { + // Introduce a common denominator so that the deltas to the boundaries are + // integers. + denominator->ShiftLeft(1); + numerator->ShiftLeft(1); + // Let v = f * 2^e, then m+ - v = 1/2 * 2^e; With the common + // denominator (of 2) delta_plus equals 2^e. + // Given that the denominator already includes v's exponent the distance + // to the boundaries is simply 1. + delta_plus->AssignUInt16(1); + // Same for delta_minus. The adjustments if f == 2^p-1 are done later. + delta_minus->AssignUInt16(1); + } +} + + +// See comments for InitialScaledStartValues +static void InitialScaledStartValuesNegativeExponentNegativePower( + uint64_t significand, int exponent, + int estimated_power, bool need_boundary_deltas, + Bignum* numerator, Bignum* denominator, + Bignum* delta_minus, Bignum* delta_plus) { + // Instead of multiplying the denominator with 10^estimated_power we + // multiply all values (numerator and deltas) by 10^-estimated_power. + + // Use numerator as temporary container for power_ten. + Bignum* power_ten = numerator; + power_ten->AssignPowerUInt16(10, -estimated_power); + + if (need_boundary_deltas) { + // Since power_ten == numerator we must make a copy of 10^estimated_power + // before we complete the computation of the numerator. + // delta_plus = delta_minus = 10^estimated_power + delta_plus->AssignBignum(*power_ten); + delta_minus->AssignBignum(*power_ten); + } + + // numerator = significand * 2 * 10^-estimated_power + // since v = significand * 2^exponent this is equivalent to + // numerator = v * 10^-estimated_power * 2 * 2^-exponent. + // Remember: numerator has been abused as power_ten. So no need to assign it + // to itself. + ASSERT(numerator == power_ten); + numerator->MultiplyByUInt64(significand); + + // denominator = 2 * 2^-exponent with exponent < 0. + denominator->AssignUInt16(1); + denominator->ShiftLeft(-exponent); + + if (need_boundary_deltas) { + // Introduce a common denominator so that the deltas to the boundaries are + // integers. + numerator->ShiftLeft(1); + denominator->ShiftLeft(1); + // With this shift the boundaries have their correct value, since + // delta_plus = 10^-estimated_power, and + // delta_minus = 10^-estimated_power. + // These assignments have been done earlier. + // The adjustments if f == 2^p-1 (lower boundary is closer) are done later. + } +} + + +// Let v = significand * 2^exponent. +// Computes v / 10^estimated_power exactly, as a ratio of two bignums, numerator +// and denominator. The functions GenerateShortestDigits and +// GenerateCountedDigits will then convert this ratio to its decimal +// representation d, with the required accuracy. +// Then d * 10^estimated_power is the representation of v. +// (Note: the fraction and the estimated_power might get adjusted before +// generating the decimal representation.) +// +// The initial start values consist of: +// - a scaled numerator: s.t. numerator/denominator == v / 10^estimated_power. +// - a scaled (common) denominator. +// optionally (used by GenerateShortestDigits to decide if it has the shortest +// decimal converting back to v): +// - v - m-: the distance to the lower boundary. +// - m+ - v: the distance to the upper boundary. +// +// v, m+, m-, and therefore v - m- and m+ - v all share the same denominator. +// +// Let ep == estimated_power, then the returned values will satisfy: +// v / 10^ep = numerator / denominator. +// v's boundarys m- and m+: +// m- / 10^ep == v / 10^ep - delta_minus / denominator +// m+ / 10^ep == v / 10^ep + delta_plus / denominator +// Or in other words: +// m- == v - delta_minus * 10^ep / denominator; +// m+ == v + delta_plus * 10^ep / denominator; +// +// Since 10^(k-1) <= v < 10^k (with k == estimated_power) +// or 10^k <= v < 10^(k+1) +// we then have 0.1 <= numerator/denominator < 1 +// or 1 <= numerator/denominator < 10 +// +// It is then easy to kickstart the digit-generation routine. +// +// The boundary-deltas are only filled if the mode equals BIGNUM_DTOA_SHORTEST +// or BIGNUM_DTOA_SHORTEST_SINGLE. + +static void InitialScaledStartValues(uint64_t significand, + int exponent, + bool lower_boundary_is_closer, + int estimated_power, + bool need_boundary_deltas, + Bignum* numerator, + Bignum* denominator, + Bignum* delta_minus, + Bignum* delta_plus) { + if (exponent >= 0) { + InitialScaledStartValuesPositiveExponent( + significand, exponent, estimated_power, need_boundary_deltas, + numerator, denominator, delta_minus, delta_plus); + } else if (estimated_power >= 0) { + InitialScaledStartValuesNegativeExponentPositivePower( + significand, exponent, estimated_power, need_boundary_deltas, + numerator, denominator, delta_minus, delta_plus); + } else { + InitialScaledStartValuesNegativeExponentNegativePower( + significand, exponent, estimated_power, need_boundary_deltas, + numerator, denominator, delta_minus, delta_plus); + } + + if (need_boundary_deltas && lower_boundary_is_closer) { + // The lower boundary is closer at half the distance of "normal" numbers. + // Increase the common denominator and adapt all but the delta_minus. + denominator->ShiftLeft(1); // *2 + numerator->ShiftLeft(1); // *2 + delta_plus->ShiftLeft(1); // *2 + } +} + + +// This routine multiplies numerator/denominator so that its values lies in the +// range 1-10. That is after a call to this function we have: +// 1 <= (numerator + delta_plus) /denominator < 10. +// Let numerator the input before modification and numerator' the argument +// after modification, then the output-parameter decimal_point is such that +// numerator / denominator * 10^estimated_power == +// numerator' / denominator' * 10^(decimal_point - 1) +// In some cases estimated_power was too low, and this is already the case. We +// then simply adjust the power so that 10^(k-1) <= v < 10^k (with k == +// estimated_power) but do not touch the numerator or denominator. +// Otherwise the routine multiplies the numerator and the deltas by 10. +static void FixupMultiply10(int estimated_power, bool is_even, + int* decimal_point, + Bignum* numerator, Bignum* denominator, + Bignum* delta_minus, Bignum* delta_plus) { + bool in_range; + if (is_even) { + // For IEEE doubles half-way cases (in decimal system numbers ending with 5) + // are rounded to the closest floating-point number with even significand. + in_range = Bignum::PlusCompare(*numerator, *delta_plus, *denominator) >= 0; + } else { + in_range = Bignum::PlusCompare(*numerator, *delta_plus, *denominator) > 0; + } + if (in_range) { + // Since numerator + delta_plus >= denominator we already have + // 1 <= numerator/denominator < 10. Simply update the estimated_power. + *decimal_point = estimated_power + 1; + } else { + *decimal_point = estimated_power; + numerator->Times10(); + if (Bignum::Equal(*delta_minus, *delta_plus)) { + delta_minus->Times10(); + delta_plus->AssignBignum(*delta_minus); + } else { + delta_minus->Times10(); + delta_plus->Times10(); + } + } +} + +} // namespace double_conversion diff --git a/mfbt/double-conversion/bignum-dtoa.h b/mfbt/double-conversion/bignum-dtoa.h new file mode 100644 index 000000000..34b961992 --- /dev/null +++ b/mfbt/double-conversion/bignum-dtoa.h @@ -0,0 +1,84 @@ +// Copyright 2010 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#ifndef DOUBLE_CONVERSION_BIGNUM_DTOA_H_ +#define DOUBLE_CONVERSION_BIGNUM_DTOA_H_ + +#include "utils.h" + +namespace double_conversion { + +enum BignumDtoaMode { + // Return the shortest correct representation. + // For example the output of 0.299999999999999988897 is (the less accurate but + // correct) 0.3. + BIGNUM_DTOA_SHORTEST, + // Same as BIGNUM_DTOA_SHORTEST but for single-precision floats. + BIGNUM_DTOA_SHORTEST_SINGLE, + // Return a fixed number of digits after the decimal point. + // For instance fixed(0.1, 4) becomes 0.1000 + // If the input number is big, the output will be big. + BIGNUM_DTOA_FIXED, + // Return a fixed number of digits, no matter what the exponent is. + BIGNUM_DTOA_PRECISION +}; + +// Converts the given double 'v' to ascii. +// The result should be interpreted as buffer * 10^(point-length). +// The buffer will be null-terminated. +// +// The input v must be > 0 and different from NaN, and Infinity. +// +// The output depends on the given mode: +// - SHORTEST: produce the least amount of digits for which the internal +// identity requirement is still satisfied. If the digits are printed +// (together with the correct exponent) then reading this number will give +// 'v' again. The buffer will choose the representation that is closest to +// 'v'. If there are two at the same distance, than the number is round up. +// In this mode the 'requested_digits' parameter is ignored. +// - FIXED: produces digits necessary to print a given number with +// 'requested_digits' digits after the decimal point. The produced digits +// might be too short in which case the caller has to fill the gaps with '0's. +// Example: toFixed(0.001, 5) is allowed to return buffer="1", point=-2. +// Halfway cases are rounded up. The call toFixed(0.15, 2) thus returns +// buffer="2", point=0. +// Note: the length of the returned buffer has no meaning wrt the significance +// of its digits. That is, just because it contains '0's does not mean that +// any other digit would not satisfy the internal identity requirement. +// - PRECISION: produces 'requested_digits' where the first digit is not '0'. +// Even though the length of produced digits usually equals +// 'requested_digits', the function is allowed to return fewer digits, in +// which case the caller has to fill the missing digits with '0's. +// Halfway cases are again rounded up. +// 'BignumDtoa' expects the given buffer to be big enough to hold all digits +// and a terminating null-character. +void BignumDtoa(double v, BignumDtoaMode mode, int requested_digits, + Vector<char> buffer, int* length, int* point); + +} // namespace double_conversion + +#endif // DOUBLE_CONVERSION_BIGNUM_DTOA_H_ diff --git a/mfbt/double-conversion/bignum.cc b/mfbt/double-conversion/bignum.cc new file mode 100644 index 000000000..dc8a2a63e --- /dev/null +++ b/mfbt/double-conversion/bignum.cc @@ -0,0 +1,763 @@ +// Copyright 2010 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#include "bignum.h" +#include "utils.h" + +namespace double_conversion { + +Bignum::Bignum() + : bigits_(bigits_buffer_, kBigitCapacity), used_digits_(0), exponent_(0) { + for (int i = 0; i < kBigitCapacity; ++i) { + bigits_[i] = 0; + } +} + + +template<typename S> +static int BitSize(S value) { + return 8 * sizeof(value); +} + +// Guaranteed to lie in one Bigit. +void Bignum::AssignUInt16(uint16_t value) { + ASSERT(kBigitSize >= BitSize(value)); + Zero(); + if (value == 0) return; + + EnsureCapacity(1); + bigits_[0] = value; + used_digits_ = 1; +} + + +void Bignum::AssignUInt64(uint64_t value) { + const int kUInt64Size = 64; + + Zero(); + if (value == 0) return; + + int needed_bigits = kUInt64Size / kBigitSize + 1; + EnsureCapacity(needed_bigits); + for (int i = 0; i < needed_bigits; ++i) { + bigits_[i] = value & kBigitMask; + value = value >> kBigitSize; + } + used_digits_ = needed_bigits; + Clamp(); +} + + +void Bignum::AssignBignum(const Bignum& other) { + exponent_ = other.exponent_; + for (int i = 0; i < other.used_digits_; ++i) { + bigits_[i] = other.bigits_[i]; + } + // Clear the excess digits (if there were any). + for (int i = other.used_digits_; i < used_digits_; ++i) { + bigits_[i] = 0; + } + used_digits_ = other.used_digits_; +} + + +static uint64_t ReadUInt64(Vector<const char> buffer, + int from, + int digits_to_read) { + uint64_t result = 0; + for (int i = from; i < from + digits_to_read; ++i) { + int digit = buffer[i] - '0'; + ASSERT(0 <= digit && digit <= 9); + result = result * 10 + digit; + } + return result; +} + + +void Bignum::AssignDecimalString(Vector<const char> value) { + // 2^64 = 18446744073709551616 > 10^19 + const int kMaxUint64DecimalDigits = 19; + Zero(); + int length = value.length(); + int pos = 0; + // Let's just say that each digit needs 4 bits. + while (length >= kMaxUint64DecimalDigits) { + uint64_t digits = ReadUInt64(value, pos, kMaxUint64DecimalDigits); + pos += kMaxUint64DecimalDigits; + length -= kMaxUint64DecimalDigits; + MultiplyByPowerOfTen(kMaxUint64DecimalDigits); + AddUInt64(digits); + } + uint64_t digits = ReadUInt64(value, pos, length); + MultiplyByPowerOfTen(length); + AddUInt64(digits); + Clamp(); +} + + +static int HexCharValue(char c) { + if ('0' <= c && c <= '9') return c - '0'; + if ('a' <= c && c <= 'f') return 10 + c - 'a'; + if ('A' <= c && c <= 'F') return 10 + c - 'A'; + UNREACHABLE(); + return 0; // To make compiler happy. +} + + +void Bignum::AssignHexString(Vector<const char> value) { + Zero(); + int length = value.length(); + + int needed_bigits = length * 4 / kBigitSize + 1; + EnsureCapacity(needed_bigits); + int string_index = length - 1; + for (int i = 0; i < needed_bigits - 1; ++i) { + // These bigits are guaranteed to be "full". + Chunk current_bigit = 0; + for (int j = 0; j < kBigitSize / 4; j++) { + current_bigit += HexCharValue(value[string_index--]) << (j * 4); + } + bigits_[i] = current_bigit; + } + used_digits_ = needed_bigits - 1; + + Chunk most_significant_bigit = 0; // Could be = 0; + for (int j = 0; j <= string_index; ++j) { + most_significant_bigit <<= 4; + most_significant_bigit += HexCharValue(value[j]); + } + if (most_significant_bigit != 0) { + bigits_[used_digits_] = most_significant_bigit; + used_digits_++; + } + Clamp(); +} + + +void Bignum::AddUInt64(uint64_t operand) { + if (operand == 0) return; + Bignum other; + other.AssignUInt64(operand); + AddBignum(other); +} + + +void Bignum::AddBignum(const Bignum& other) { + ASSERT(IsClamped()); + ASSERT(other.IsClamped()); + + // If this has a greater exponent than other append zero-bigits to this. + // After this call exponent_ <= other.exponent_. + Align(other); + + // There are two possibilities: + // aaaaaaaaaaa 0000 (where the 0s represent a's exponent) + // bbbbb 00000000 + // ---------------- + // ccccccccccc 0000 + // or + // aaaaaaaaaa 0000 + // bbbbbbbbb 0000000 + // ----------------- + // cccccccccccc 0000 + // In both cases we might need a carry bigit. + + EnsureCapacity(1 + Max(BigitLength(), other.BigitLength()) - exponent_); + Chunk carry = 0; + int bigit_pos = other.exponent_ - exponent_; + ASSERT(bigit_pos >= 0); + for (int i = 0; i < other.used_digits_; ++i) { + Chunk sum = bigits_[bigit_pos] + other.bigits_[i] + carry; + bigits_[bigit_pos] = sum & kBigitMask; + carry = sum >> kBigitSize; + bigit_pos++; + } + + while (carry != 0) { + Chunk sum = bigits_[bigit_pos] + carry; + bigits_[bigit_pos] = sum & kBigitMask; + carry = sum >> kBigitSize; + bigit_pos++; + } + used_digits_ = Max(bigit_pos, used_digits_); + ASSERT(IsClamped()); +} + + +void Bignum::SubtractBignum(const Bignum& other) { + ASSERT(IsClamped()); + ASSERT(other.IsClamped()); + // We require this to be bigger than other. + ASSERT(LessEqual(other, *this)); + + Align(other); + + int offset = other.exponent_ - exponent_; + Chunk borrow = 0; + int i; + for (i = 0; i < other.used_digits_; ++i) { + ASSERT((borrow == 0) || (borrow == 1)); + Chunk difference = bigits_[i + offset] - other.bigits_[i] - borrow; + bigits_[i + offset] = difference & kBigitMask; + borrow = difference >> (kChunkSize - 1); + } + while (borrow != 0) { + Chunk difference = bigits_[i + offset] - borrow; + bigits_[i + offset] = difference & kBigitMask; + borrow = difference >> (kChunkSize - 1); + ++i; + } + Clamp(); +} + + +void Bignum::ShiftLeft(int shift_amount) { + if (used_digits_ == 0) return; + exponent_ += shift_amount / kBigitSize; + int local_shift = shift_amount % kBigitSize; + EnsureCapacity(used_digits_ + 1); + BigitsShiftLeft(local_shift); +} + + +void Bignum::MultiplyByUInt32(uint32_t factor) { + if (factor == 1) return; + if (factor == 0) { + Zero(); + return; + } + if (used_digits_ == 0) return; + + // The product of a bigit with the factor is of size kBigitSize + 32. + // Assert that this number + 1 (for the carry) fits into double chunk. + ASSERT(kDoubleChunkSize >= kBigitSize + 32 + 1); + DoubleChunk carry = 0; + for (int i = 0; i < used_digits_; ++i) { + DoubleChunk product = static_cast<DoubleChunk>(factor) * bigits_[i] + carry; + bigits_[i] = static_cast<Chunk>(product & kBigitMask); + carry = (product >> kBigitSize); + } + while (carry != 0) { + EnsureCapacity(used_digits_ + 1); + bigits_[used_digits_] = carry & kBigitMask; + used_digits_++; + carry >>= kBigitSize; + } +} + + +void Bignum::MultiplyByUInt64(uint64_t factor) { + if (factor == 1) return; + if (factor == 0) { + Zero(); + return; + } + ASSERT(kBigitSize < 32); + uint64_t carry = 0; + uint64_t low = factor & 0xFFFFFFFF; + uint64_t high = factor >> 32; + for (int i = 0; i < used_digits_; ++i) { + uint64_t product_low = low * bigits_[i]; + uint64_t product_high = high * bigits_[i]; + uint64_t tmp = (carry & kBigitMask) + product_low; + bigits_[i] = tmp & kBigitMask; + carry = (carry >> kBigitSize) + (tmp >> kBigitSize) + + (product_high << (32 - kBigitSize)); + } + while (carry != 0) { + EnsureCapacity(used_digits_ + 1); + bigits_[used_digits_] = carry & kBigitMask; + used_digits_++; + carry >>= kBigitSize; + } +} + + +void Bignum::MultiplyByPowerOfTen(int exponent) { + const uint64_t kFive27 = UINT64_2PART_C(0x6765c793, fa10079d); + const uint16_t kFive1 = 5; + const uint16_t kFive2 = kFive1 * 5; + const uint16_t kFive3 = kFive2 * 5; + const uint16_t kFive4 = kFive3 * 5; + const uint16_t kFive5 = kFive4 * 5; + const uint16_t kFive6 = kFive5 * 5; + const uint32_t kFive7 = kFive6 * 5; + const uint32_t kFive8 = kFive7 * 5; + const uint32_t kFive9 = kFive8 * 5; + const uint32_t kFive10 = kFive9 * 5; + const uint32_t kFive11 = kFive10 * 5; + const uint32_t kFive12 = kFive11 * 5; + const uint32_t kFive13 = kFive12 * 5; + const uint32_t kFive1_to_12[] = + { kFive1, kFive2, kFive3, kFive4, kFive5, kFive6, + kFive7, kFive8, kFive9, kFive10, kFive11, kFive12 }; + + ASSERT(exponent >= 0); + if (exponent == 0) return; + if (used_digits_ == 0) return; + + // We shift by exponent at the end just before returning. + int remaining_exponent = exponent; + while (remaining_exponent >= 27) { + MultiplyByUInt64(kFive27); + remaining_exponent -= 27; + } + while (remaining_exponent >= 13) { + MultiplyByUInt32(kFive13); + remaining_exponent -= 13; + } + if (remaining_exponent > 0) { + MultiplyByUInt32(kFive1_to_12[remaining_exponent - 1]); + } + ShiftLeft(exponent); +} + + +void Bignum::Square() { + ASSERT(IsClamped()); + int product_length = 2 * used_digits_; + EnsureCapacity(product_length); + + // Comba multiplication: compute each column separately. + // Example: r = a2a1a0 * b2b1b0. + // r = 1 * a0b0 + + // 10 * (a1b0 + a0b1) + + // 100 * (a2b0 + a1b1 + a0b2) + + // 1000 * (a2b1 + a1b2) + + // 10000 * a2b2 + // + // In the worst case we have to accumulate nb-digits products of digit*digit. + // + // Assert that the additional number of bits in a DoubleChunk are enough to + // sum up used_digits of Bigit*Bigit. + if ((1 << (2 * (kChunkSize - kBigitSize))) <= used_digits_) { + UNIMPLEMENTED(); + } + DoubleChunk accumulator = 0; + // First shift the digits so we don't overwrite them. + int copy_offset = used_digits_; + for (int i = 0; i < used_digits_; ++i) { + bigits_[copy_offset + i] = bigits_[i]; + } + // We have two loops to avoid some 'if's in the loop. + for (int i = 0; i < used_digits_; ++i) { + // Process temporary digit i with power i. + // The sum of the two indices must be equal to i. + int bigit_index1 = i; + int bigit_index2 = 0; + // Sum all of the sub-products. + while (bigit_index1 >= 0) { + Chunk chunk1 = bigits_[copy_offset + bigit_index1]; + Chunk chunk2 = bigits_[copy_offset + bigit_index2]; + accumulator += static_cast<DoubleChunk>(chunk1) * chunk2; + bigit_index1--; + bigit_index2++; + } + bigits_[i] = static_cast<Chunk>(accumulator) & kBigitMask; + accumulator >>= kBigitSize; + } + for (int i = used_digits_; i < product_length; ++i) { + int bigit_index1 = used_digits_ - 1; + int bigit_index2 = i - bigit_index1; + // Invariant: sum of both indices is again equal to i. + // Inner loop runs 0 times on last iteration, emptying accumulator. + while (bigit_index2 < used_digits_) { + Chunk chunk1 = bigits_[copy_offset + bigit_index1]; + Chunk chunk2 = bigits_[copy_offset + bigit_index2]; + accumulator += static_cast<DoubleChunk>(chunk1) * chunk2; + bigit_index1--; + bigit_index2++; + } + // The overwritten bigits_[i] will never be read in further loop iterations, + // because bigit_index1 and bigit_index2 are always greater + // than i - used_digits_. + bigits_[i] = static_cast<Chunk>(accumulator) & kBigitMask; + accumulator >>= kBigitSize; + } + // Since the result was guaranteed to lie inside the number the + // accumulator must be 0 now. + ASSERT(accumulator == 0); + + // Don't forget to update the used_digits and the exponent. + used_digits_ = product_length; + exponent_ *= 2; + Clamp(); +} + + +void Bignum::AssignPowerUInt16(uint16_t base, int power_exponent) { + ASSERT(base != 0); + ASSERT(power_exponent >= 0); + if (power_exponent == 0) { + AssignUInt16(1); + return; + } + Zero(); + int shifts = 0; + // We expect base to be in range 2-32, and most often to be 10. + // It does not make much sense to implement different algorithms for counting + // the bits. + while ((base & 1) == 0) { + base >>= 1; + shifts++; + } + int bit_size = 0; + int tmp_base = base; + while (tmp_base != 0) { + tmp_base >>= 1; + bit_size++; + } + int final_size = bit_size * power_exponent; + // 1 extra bigit for the shifting, and one for rounded final_size. + EnsureCapacity(final_size / kBigitSize + 2); + + // Left to Right exponentiation. + int mask = 1; + while (power_exponent >= mask) mask <<= 1; + + // The mask is now pointing to the bit above the most significant 1-bit of + // power_exponent. + // Get rid of first 1-bit; + mask >>= 2; + uint64_t this_value = base; + + bool delayed_multipliciation = false; + const uint64_t max_32bits = 0xFFFFFFFF; + while (mask != 0 && this_value <= max_32bits) { + this_value = this_value * this_value; + // Verify that there is enough space in this_value to perform the + // multiplication. The first bit_size bits must be 0. + if ((power_exponent & mask) != 0) { + uint64_t base_bits_mask = + ~((static_cast<uint64_t>(1) << (64 - bit_size)) - 1); + bool high_bits_zero = (this_value & base_bits_mask) == 0; + if (high_bits_zero) { + this_value *= base; + } else { + delayed_multipliciation = true; + } + } + mask >>= 1; + } + AssignUInt64(this_value); + if (delayed_multipliciation) { + MultiplyByUInt32(base); + } + + // Now do the same thing as a bignum. + while (mask != 0) { + Square(); + if ((power_exponent & mask) != 0) { + MultiplyByUInt32(base); + } + mask >>= 1; + } + + // And finally add the saved shifts. + ShiftLeft(shifts * power_exponent); +} + + +// Precondition: this/other < 16bit. +uint16_t Bignum::DivideModuloIntBignum(const Bignum& other) { + ASSERT(IsClamped()); + ASSERT(other.IsClamped()); + ASSERT(other.used_digits_ > 0); + + // Easy case: if we have less digits than the divisor than the result is 0. + // Note: this handles the case where this == 0, too. + if (BigitLength() < other.BigitLength()) { + return 0; + } + + Align(other); + + uint16_t result = 0; + + // Start by removing multiples of 'other' until both numbers have the same + // number of digits. + while (BigitLength() > other.BigitLength()) { + // This naive approach is extremely inefficient if `this` divided by other + // is big. This function is implemented for doubleToString where + // the result should be small (less than 10). + ASSERT(other.bigits_[other.used_digits_ - 1] >= ((1 << kBigitSize) / 16)); + // Remove the multiples of the first digit. + // Example this = 23 and other equals 9. -> Remove 2 multiples. + result += bigits_[used_digits_ - 1]; + SubtractTimes(other, bigits_[used_digits_ - 1]); + } + + ASSERT(BigitLength() == other.BigitLength()); + + // Both bignums are at the same length now. + // Since other has more than 0 digits we know that the access to + // bigits_[used_digits_ - 1] is safe. + Chunk this_bigit = bigits_[used_digits_ - 1]; + Chunk other_bigit = other.bigits_[other.used_digits_ - 1]; + + if (other.used_digits_ == 1) { + // Shortcut for easy (and common) case. + int quotient = this_bigit / other_bigit; + bigits_[used_digits_ - 1] = this_bigit - other_bigit * quotient; + result += quotient; + Clamp(); + return result; + } + + int division_estimate = this_bigit / (other_bigit + 1); + result += division_estimate; + SubtractTimes(other, division_estimate); + + if (other_bigit * (division_estimate + 1) > this_bigit) { + // No need to even try to subtract. Even if other's remaining digits were 0 + // another subtraction would be too much. + return result; + } + + while (LessEqual(other, *this)) { + SubtractBignum(other); + result++; + } + return result; +} + + +template<typename S> +static int SizeInHexChars(S number) { + ASSERT(number > 0); + int result = 0; + while (number != 0) { + number >>= 4; + result++; + } + return result; +} + + +static char HexCharOfValue(int value) { + ASSERT(0 <= value && value <= 16); + if (value < 10) return value + '0'; + return value - 10 + 'A'; +} + + +bool Bignum::ToHexString(char* buffer, int buffer_size) const { + ASSERT(IsClamped()); + // Each bigit must be printable as separate hex-character. + ASSERT(kBigitSize % 4 == 0); + const int kHexCharsPerBigit = kBigitSize / 4; + + if (used_digits_ == 0) { + if (buffer_size < 2) return false; + buffer[0] = '0'; + buffer[1] = '\0'; + return true; + } + // We add 1 for the terminating '\0' character. + int needed_chars = (BigitLength() - 1) * kHexCharsPerBigit + + SizeInHexChars(bigits_[used_digits_ - 1]) + 1; + if (needed_chars > buffer_size) return false; + int string_index = needed_chars - 1; + buffer[string_index--] = '\0'; + for (int i = 0; i < exponent_; ++i) { + for (int j = 0; j < kHexCharsPerBigit; ++j) { + buffer[string_index--] = '0'; + } + } + for (int i = 0; i < used_digits_ - 1; ++i) { + Chunk current_bigit = bigits_[i]; + for (int j = 0; j < kHexCharsPerBigit; ++j) { + buffer[string_index--] = HexCharOfValue(current_bigit & 0xF); + current_bigit >>= 4; + } + } + // And finally the last bigit. + Chunk most_significant_bigit = bigits_[used_digits_ - 1]; + while (most_significant_bigit != 0) { + buffer[string_index--] = HexCharOfValue(most_significant_bigit & 0xF); + most_significant_bigit >>= 4; + } + return true; +} + + +Bignum::Chunk Bignum::BigitAt(int index) const { + if (index >= BigitLength()) return 0; + if (index < exponent_) return 0; + return bigits_[index - exponent_]; +} + + +int Bignum::Compare(const Bignum& a, const Bignum& b) { + ASSERT(a.IsClamped()); + ASSERT(b.IsClamped()); + int bigit_length_a = a.BigitLength(); + int bigit_length_b = b.BigitLength(); + if (bigit_length_a < bigit_length_b) return -1; + if (bigit_length_a > bigit_length_b) return +1; + for (int i = bigit_length_a - 1; i >= Min(a.exponent_, b.exponent_); --i) { + Chunk bigit_a = a.BigitAt(i); + Chunk bigit_b = b.BigitAt(i); + if (bigit_a < bigit_b) return -1; + if (bigit_a > bigit_b) return +1; + // Otherwise they are equal up to this digit. Try the next digit. + } + return 0; +} + + +int Bignum::PlusCompare(const Bignum& a, const Bignum& b, const Bignum& c) { + ASSERT(a.IsClamped()); + ASSERT(b.IsClamped()); + ASSERT(c.IsClamped()); + if (a.BigitLength() < b.BigitLength()) { + return PlusCompare(b, a, c); + } + if (a.BigitLength() + 1 < c.BigitLength()) return -1; + if (a.BigitLength() > c.BigitLength()) return +1; + // The exponent encodes 0-bigits. So if there are more 0-digits in 'a' than + // 'b' has digits, then the bigit-length of 'a'+'b' must be equal to the one + // of 'a'. + if (a.exponent_ >= b.BigitLength() && a.BigitLength() < c.BigitLength()) { + return -1; + } + + Chunk borrow = 0; + // Starting at min_exponent all digits are == 0. So no need to compare them. + int min_exponent = Min(Min(a.exponent_, b.exponent_), c.exponent_); + for (int i = c.BigitLength() - 1; i >= min_exponent; --i) { + Chunk chunk_a = a.BigitAt(i); + Chunk chunk_b = b.BigitAt(i); + Chunk chunk_c = c.BigitAt(i); + Chunk sum = chunk_a + chunk_b; + if (sum > chunk_c + borrow) { + return +1; + } else { + borrow = chunk_c + borrow - sum; + if (borrow > 1) return -1; + borrow <<= kBigitSize; + } + } + if (borrow == 0) return 0; + return -1; +} + + +void Bignum::Clamp() { + while (used_digits_ > 0 && bigits_[used_digits_ - 1] == 0) { + used_digits_--; + } + if (used_digits_ == 0) { + // Zero. + exponent_ = 0; + } +} + + +bool Bignum::IsClamped() const { + return used_digits_ == 0 || bigits_[used_digits_ - 1] != 0; +} + + +void Bignum::Zero() { + for (int i = 0; i < used_digits_; ++i) { + bigits_[i] = 0; + } + used_digits_ = 0; + exponent_ = 0; +} + + +void Bignum::Align(const Bignum& other) { + if (exponent_ > other.exponent_) { + // If "X" represents a "hidden" digit (by the exponent) then we are in the + // following case (a == this, b == other): + // a: aaaaaaXXXX or a: aaaaaXXX + // b: bbbbbbX b: bbbbbbbbXX + // We replace some of the hidden digits (X) of a with 0 digits. + // a: aaaaaa000X or a: aaaaa0XX + int zero_digits = exponent_ - other.exponent_; + EnsureCapacity(used_digits_ + zero_digits); + for (int i = used_digits_ - 1; i >= 0; --i) { + bigits_[i + zero_digits] = bigits_[i]; + } + for (int i = 0; i < zero_digits; ++i) { + bigits_[i] = 0; + } + used_digits_ += zero_digits; + exponent_ -= zero_digits; + ASSERT(used_digits_ >= 0); + ASSERT(exponent_ >= 0); + } +} + + +void Bignum::BigitsShiftLeft(int shift_amount) { + ASSERT(shift_amount < kBigitSize); + ASSERT(shift_amount >= 0); + Chunk carry = 0; + for (int i = 0; i < used_digits_; ++i) { + Chunk new_carry = bigits_[i] >> (kBigitSize - shift_amount); + bigits_[i] = ((bigits_[i] << shift_amount) + carry) & kBigitMask; + carry = new_carry; + } + if (carry != 0) { + bigits_[used_digits_] = carry; + used_digits_++; + } +} + + +void Bignum::SubtractTimes(const Bignum& other, int factor) { + ASSERT(exponent_ <= other.exponent_); + if (factor < 3) { + for (int i = 0; i < factor; ++i) { + SubtractBignum(other); + } + return; + } + Chunk borrow = 0; + int exponent_diff = other.exponent_ - exponent_; + for (int i = 0; i < other.used_digits_; ++i) { + DoubleChunk product = static_cast<DoubleChunk>(factor) * other.bigits_[i]; + DoubleChunk remove = borrow + product; + Chunk difference = bigits_[i + exponent_diff] - (remove & kBigitMask); + bigits_[i + exponent_diff] = difference & kBigitMask; + borrow = static_cast<Chunk>((difference >> (kChunkSize - 1)) + + (remove >> kBigitSize)); + } + for (int i = other.used_digits_ + exponent_diff; i < used_digits_; ++i) { + if (borrow == 0) return; + Chunk difference = bigits_[i] - borrow; + bigits_[i] = difference & kBigitMask; + borrow = difference >> (kChunkSize - 1); + } + Clamp(); +} + + +} // namespace double_conversion diff --git a/mfbt/double-conversion/bignum.h b/mfbt/double-conversion/bignum.h new file mode 100644 index 000000000..5ec3544f5 --- /dev/null +++ b/mfbt/double-conversion/bignum.h @@ -0,0 +1,145 @@ +// Copyright 2010 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#ifndef DOUBLE_CONVERSION_BIGNUM_H_ +#define DOUBLE_CONVERSION_BIGNUM_H_ + +#include "utils.h" + +namespace double_conversion { + +class Bignum { + public: + // 3584 = 128 * 28. We can represent 2^3584 > 10^1000 accurately. + // This bignum can encode much bigger numbers, since it contains an + // exponent. + static const int kMaxSignificantBits = 3584; + + Bignum(); + void AssignUInt16(uint16_t value); + void AssignUInt64(uint64_t value); + void AssignBignum(const Bignum& other); + + void AssignDecimalString(Vector<const char> value); + void AssignHexString(Vector<const char> value); + + void AssignPowerUInt16(uint16_t base, int exponent); + + void AddUInt16(uint16_t operand); + void AddUInt64(uint64_t operand); + void AddBignum(const Bignum& other); + // Precondition: this >= other. + void SubtractBignum(const Bignum& other); + + void Square(); + void ShiftLeft(int shift_amount); + void MultiplyByUInt32(uint32_t factor); + void MultiplyByUInt64(uint64_t factor); + void MultiplyByPowerOfTen(int exponent); + void Times10() { return MultiplyByUInt32(10); } + // Pseudocode: + // int result = this / other; + // this = this % other; + // In the worst case this function is in O(this/other). + uint16_t DivideModuloIntBignum(const Bignum& other); + + bool ToHexString(char* buffer, int buffer_size) const; + + // Returns + // -1 if a < b, + // 0 if a == b, and + // +1 if a > b. + static int Compare(const Bignum& a, const Bignum& b); + static bool Equal(const Bignum& a, const Bignum& b) { + return Compare(a, b) == 0; + } + static bool LessEqual(const Bignum& a, const Bignum& b) { + return Compare(a, b) <= 0; + } + static bool Less(const Bignum& a, const Bignum& b) { + return Compare(a, b) < 0; + } + // Returns Compare(a + b, c); + static int PlusCompare(const Bignum& a, const Bignum& b, const Bignum& c); + // Returns a + b == c + static bool PlusEqual(const Bignum& a, const Bignum& b, const Bignum& c) { + return PlusCompare(a, b, c) == 0; + } + // Returns a + b <= c + static bool PlusLessEqual(const Bignum& a, const Bignum& b, const Bignum& c) { + return PlusCompare(a, b, c) <= 0; + } + // Returns a + b < c + static bool PlusLess(const Bignum& a, const Bignum& b, const Bignum& c) { + return PlusCompare(a, b, c) < 0; + } + private: + typedef uint32_t Chunk; + typedef uint64_t DoubleChunk; + + static const int kChunkSize = sizeof(Chunk) * 8; + static const int kDoubleChunkSize = sizeof(DoubleChunk) * 8; + // With bigit size of 28 we loose some bits, but a double still fits easily + // into two chunks, and more importantly we can use the Comba multiplication. + static const int kBigitSize = 28; + static const Chunk kBigitMask = (1 << kBigitSize) - 1; + // Every instance allocates kBigitLength chunks on the stack. Bignums cannot + // grow. There are no checks if the stack-allocated space is sufficient. + static const int kBigitCapacity = kMaxSignificantBits / kBigitSize; + + void EnsureCapacity(int size) { + if (size > kBigitCapacity) { + UNREACHABLE(); + } + } + void Align(const Bignum& other); + void Clamp(); + bool IsClamped() const; + void Zero(); + // Requires this to have enough capacity (no tests done). + // Updates used_digits_ if necessary. + // shift_amount must be < kBigitSize. + void BigitsShiftLeft(int shift_amount); + // BigitLength includes the "hidden" digits encoded in the exponent. + int BigitLength() const { return used_digits_ + exponent_; } + Chunk BigitAt(int index) const; + void SubtractTimes(const Bignum& other, int factor); + + Chunk bigits_buffer_[kBigitCapacity]; + // A vector backed by bigits_buffer_. This way accesses to the array are + // checked for out-of-bounds errors. + Vector<Chunk> bigits_; + int used_digits_; + // The Bignum's value equals value(bigits_) * 2^(exponent_ * kBigitSize). + int exponent_; + + DISALLOW_COPY_AND_ASSIGN(Bignum); +}; + +} // namespace double_conversion + +#endif // DOUBLE_CONVERSION_BIGNUM_H_ diff --git a/mfbt/double-conversion/cached-powers.cc b/mfbt/double-conversion/cached-powers.cc new file mode 100644 index 000000000..c67642919 --- /dev/null +++ b/mfbt/double-conversion/cached-powers.cc @@ -0,0 +1,175 @@ +// Copyright 2006-2008 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#include <stdarg.h> +#include <limits.h> +#include <math.h> + +#include "utils.h" + +#include "cached-powers.h" + +namespace double_conversion { + +struct CachedPower { + uint64_t significand; + int16_t binary_exponent; + int16_t decimal_exponent; +}; + +static const CachedPower kCachedPowers[] = { + {UINT64_2PART_C(0xfa8fd5a0, 081c0288), -1220, -348}, + {UINT64_2PART_C(0xbaaee17f, a23ebf76), -1193, -340}, + {UINT64_2PART_C(0x8b16fb20, 3055ac76), -1166, -332}, + {UINT64_2PART_C(0xcf42894a, 5dce35ea), -1140, -324}, + {UINT64_2PART_C(0x9a6bb0aa, 55653b2d), -1113, -316}, + {UINT64_2PART_C(0xe61acf03, 3d1a45df), -1087, -308}, + {UINT64_2PART_C(0xab70fe17, c79ac6ca), -1060, -300}, + {UINT64_2PART_C(0xff77b1fc, bebcdc4f), -1034, -292}, + {UINT64_2PART_C(0xbe5691ef, 416bd60c), -1007, -284}, + {UINT64_2PART_C(0x8dd01fad, 907ffc3c), -980, -276}, + {UINT64_2PART_C(0xd3515c28, 31559a83), -954, -268}, + {UINT64_2PART_C(0x9d71ac8f, ada6c9b5), -927, -260}, + {UINT64_2PART_C(0xea9c2277, 23ee8bcb), -901, -252}, + {UINT64_2PART_C(0xaecc4991, 4078536d), -874, -244}, + {UINT64_2PART_C(0x823c1279, 5db6ce57), -847, -236}, + {UINT64_2PART_C(0xc2109436, 4dfb5637), -821, -228}, + {UINT64_2PART_C(0x9096ea6f, 3848984f), -794, -220}, + {UINT64_2PART_C(0xd77485cb, 25823ac7), -768, -212}, + {UINT64_2PART_C(0xa086cfcd, 97bf97f4), -741, -204}, + {UINT64_2PART_C(0xef340a98, 172aace5), -715, -196}, + {UINT64_2PART_C(0xb23867fb, 2a35b28e), -688, -188}, + {UINT64_2PART_C(0x84c8d4df, d2c63f3b), -661, -180}, + {UINT64_2PART_C(0xc5dd4427, 1ad3cdba), -635, -172}, + {UINT64_2PART_C(0x936b9fce, bb25c996), -608, -164}, + {UINT64_2PART_C(0xdbac6c24, 7d62a584), -582, -156}, + {UINT64_2PART_C(0xa3ab6658, 0d5fdaf6), -555, -148}, + {UINT64_2PART_C(0xf3e2f893, dec3f126), -529, -140}, + {UINT64_2PART_C(0xb5b5ada8, aaff80b8), -502, -132}, + {UINT64_2PART_C(0x87625f05, 6c7c4a8b), -475, -124}, + {UINT64_2PART_C(0xc9bcff60, 34c13053), -449, -116}, + {UINT64_2PART_C(0x964e858c, 91ba2655), -422, -108}, + {UINT64_2PART_C(0xdff97724, 70297ebd), -396, -100}, + {UINT64_2PART_C(0xa6dfbd9f, b8e5b88f), -369, -92}, + {UINT64_2PART_C(0xf8a95fcf, 88747d94), -343, -84}, + {UINT64_2PART_C(0xb9447093, 8fa89bcf), -316, -76}, + {UINT64_2PART_C(0x8a08f0f8, bf0f156b), -289, -68}, + {UINT64_2PART_C(0xcdb02555, 653131b6), -263, -60}, + {UINT64_2PART_C(0x993fe2c6, d07b7fac), -236, -52}, + {UINT64_2PART_C(0xe45c10c4, 2a2b3b06), -210, -44}, + {UINT64_2PART_C(0xaa242499, 697392d3), -183, -36}, + {UINT64_2PART_C(0xfd87b5f2, 8300ca0e), -157, -28}, + {UINT64_2PART_C(0xbce50864, 92111aeb), -130, -20}, + {UINT64_2PART_C(0x8cbccc09, 6f5088cc), -103, -12}, + {UINT64_2PART_C(0xd1b71758, e219652c), -77, -4}, + {UINT64_2PART_C(0x9c400000, 00000000), -50, 4}, + {UINT64_2PART_C(0xe8d4a510, 00000000), -24, 12}, + {UINT64_2PART_C(0xad78ebc5, ac620000), 3, 20}, + {UINT64_2PART_C(0x813f3978, f8940984), 30, 28}, + {UINT64_2PART_C(0xc097ce7b, c90715b3), 56, 36}, + {UINT64_2PART_C(0x8f7e32ce, 7bea5c70), 83, 44}, + {UINT64_2PART_C(0xd5d238a4, abe98068), 109, 52}, + {UINT64_2PART_C(0x9f4f2726, 179a2245), 136, 60}, + {UINT64_2PART_C(0xed63a231, d4c4fb27), 162, 68}, + {UINT64_2PART_C(0xb0de6538, 8cc8ada8), 189, 76}, + {UINT64_2PART_C(0x83c7088e, 1aab65db), 216, 84}, + {UINT64_2PART_C(0xc45d1df9, 42711d9a), 242, 92}, + {UINT64_2PART_C(0x924d692c, a61be758), 269, 100}, + {UINT64_2PART_C(0xda01ee64, 1a708dea), 295, 108}, + {UINT64_2PART_C(0xa26da399, 9aef774a), 322, 116}, + {UINT64_2PART_C(0xf209787b, b47d6b85), 348, 124}, + {UINT64_2PART_C(0xb454e4a1, 79dd1877), 375, 132}, + {UINT64_2PART_C(0x865b8692, 5b9bc5c2), 402, 140}, + {UINT64_2PART_C(0xc83553c5, c8965d3d), 428, 148}, + {UINT64_2PART_C(0x952ab45c, fa97a0b3), 455, 156}, + {UINT64_2PART_C(0xde469fbd, 99a05fe3), 481, 164}, + {UINT64_2PART_C(0xa59bc234, db398c25), 508, 172}, + {UINT64_2PART_C(0xf6c69a72, a3989f5c), 534, 180}, + {UINT64_2PART_C(0xb7dcbf53, 54e9bece), 561, 188}, + {UINT64_2PART_C(0x88fcf317, f22241e2), 588, 196}, + {UINT64_2PART_C(0xcc20ce9b, d35c78a5), 614, 204}, + {UINT64_2PART_C(0x98165af3, 7b2153df), 641, 212}, + {UINT64_2PART_C(0xe2a0b5dc, 971f303a), 667, 220}, + {UINT64_2PART_C(0xa8d9d153, 5ce3b396), 694, 228}, + {UINT64_2PART_C(0xfb9b7cd9, a4a7443c), 720, 236}, + {UINT64_2PART_C(0xbb764c4c, a7a44410), 747, 244}, + {UINT64_2PART_C(0x8bab8eef, b6409c1a), 774, 252}, + {UINT64_2PART_C(0xd01fef10, a657842c), 800, 260}, + {UINT64_2PART_C(0x9b10a4e5, e9913129), 827, 268}, + {UINT64_2PART_C(0xe7109bfb, a19c0c9d), 853, 276}, + {UINT64_2PART_C(0xac2820d9, 623bf429), 880, 284}, + {UINT64_2PART_C(0x80444b5e, 7aa7cf85), 907, 292}, + {UINT64_2PART_C(0xbf21e440, 03acdd2d), 933, 300}, + {UINT64_2PART_C(0x8e679c2f, 5e44ff8f), 960, 308}, + {UINT64_2PART_C(0xd433179d, 9c8cb841), 986, 316}, + {UINT64_2PART_C(0x9e19db92, b4e31ba9), 1013, 324}, + {UINT64_2PART_C(0xeb96bf6e, badf77d9), 1039, 332}, + {UINT64_2PART_C(0xaf87023b, 9bf0ee6b), 1066, 340}, +}; + +static const int kCachedPowersLength = ARRAY_SIZE(kCachedPowers); +static const int kCachedPowersOffset = 348; // -1 * the first decimal_exponent. +static const double kD_1_LOG2_10 = 0.30102999566398114; // 1 / lg(10) +// Difference between the decimal exponents in the table above. +const int PowersOfTenCache::kDecimalExponentDistance = 8; +const int PowersOfTenCache::kMinDecimalExponent = -348; +const int PowersOfTenCache::kMaxDecimalExponent = 340; + +void PowersOfTenCache::GetCachedPowerForBinaryExponentRange( + int min_exponent, + int max_exponent, + DiyFp* power, + int* decimal_exponent) { + int kQ = DiyFp::kSignificandSize; + double k = ceil((min_exponent + kQ - 1) * kD_1_LOG2_10); + int foo = kCachedPowersOffset; + int index = + (foo + static_cast<int>(k) - 1) / kDecimalExponentDistance + 1; + ASSERT(0 <= index && index < kCachedPowersLength); + CachedPower cached_power = kCachedPowers[index]; + ASSERT(min_exponent <= cached_power.binary_exponent); + ASSERT(cached_power.binary_exponent <= max_exponent); + *decimal_exponent = cached_power.decimal_exponent; + *power = DiyFp(cached_power.significand, cached_power.binary_exponent); +} + + +void PowersOfTenCache::GetCachedPowerForDecimalExponent(int requested_exponent, + DiyFp* power, + int* found_exponent) { + ASSERT(kMinDecimalExponent <= requested_exponent); + ASSERT(requested_exponent < kMaxDecimalExponent + kDecimalExponentDistance); + int index = + (requested_exponent + kCachedPowersOffset) / kDecimalExponentDistance; + CachedPower cached_power = kCachedPowers[index]; + *power = DiyFp(cached_power.significand, cached_power.binary_exponent); + *found_exponent = cached_power.decimal_exponent; + ASSERT(*found_exponent <= requested_exponent); + ASSERT(requested_exponent < *found_exponent + kDecimalExponentDistance); +} + +} // namespace double_conversion diff --git a/mfbt/double-conversion/cached-powers.h b/mfbt/double-conversion/cached-powers.h new file mode 100644 index 000000000..61a50614c --- /dev/null +++ b/mfbt/double-conversion/cached-powers.h @@ -0,0 +1,64 @@ +// Copyright 2010 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#ifndef DOUBLE_CONVERSION_CACHED_POWERS_H_ +#define DOUBLE_CONVERSION_CACHED_POWERS_H_ + +#include "diy-fp.h" + +namespace double_conversion { + +class PowersOfTenCache { + public: + + // Not all powers of ten are cached. The decimal exponent of two neighboring + // cached numbers will differ by kDecimalExponentDistance. + static const int kDecimalExponentDistance; + + static const int kMinDecimalExponent; + static const int kMaxDecimalExponent; + + // Returns a cached power-of-ten with a binary exponent in the range + // [min_exponent; max_exponent] (boundaries included). + static void GetCachedPowerForBinaryExponentRange(int min_exponent, + int max_exponent, + DiyFp* power, + int* decimal_exponent); + + // Returns a cached power of ten x ~= 10^k such that + // k <= decimal_exponent < k + kCachedPowersDecimalDistance. + // The given decimal_exponent must satisfy + // kMinDecimalExponent <= requested_exponent, and + // requested_exponent < kMaxDecimalExponent + kDecimalExponentDistance. + static void GetCachedPowerForDecimalExponent(int requested_exponent, + DiyFp* power, + int* found_exponent); +}; + +} // namespace double_conversion + +#endif // DOUBLE_CONVERSION_CACHED_POWERS_H_ diff --git a/mfbt/double-conversion/diy-fp.cc b/mfbt/double-conversion/diy-fp.cc new file mode 100644 index 000000000..ddd1891b1 --- /dev/null +++ b/mfbt/double-conversion/diy-fp.cc @@ -0,0 +1,57 @@ +// Copyright 2010 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + + +#include "diy-fp.h" +#include "utils.h" + +namespace double_conversion { + +void DiyFp::Multiply(const DiyFp& other) { + // Simply "emulates" a 128 bit multiplication. + // However: the resulting number only contains 64 bits. The least + // significant 64 bits are only used for rounding the most significant 64 + // bits. + const uint64_t kM32 = 0xFFFFFFFFU; + uint64_t a = f_ >> 32; + uint64_t b = f_ & kM32; + uint64_t c = other.f_ >> 32; + uint64_t d = other.f_ & kM32; + uint64_t ac = a * c; + uint64_t bc = b * c; + uint64_t ad = a * d; + uint64_t bd = b * d; + uint64_t tmp = (bd >> 32) + (ad & kM32) + (bc & kM32); + // By adding 1U << 31 to tmp we round the final result. + // Halfway cases will be round up. + tmp += 1U << 31; + uint64_t result_f = ac + (ad >> 32) + (bc >> 32) + (tmp >> 32); + e_ += other.e_ + 64; + f_ = result_f; +} + +} // namespace double_conversion diff --git a/mfbt/double-conversion/diy-fp.h b/mfbt/double-conversion/diy-fp.h new file mode 100644 index 000000000..9dcf8fbdb --- /dev/null +++ b/mfbt/double-conversion/diy-fp.h @@ -0,0 +1,118 @@ +// Copyright 2010 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#ifndef DOUBLE_CONVERSION_DIY_FP_H_ +#define DOUBLE_CONVERSION_DIY_FP_H_ + +#include "utils.h" + +namespace double_conversion { + +// This "Do It Yourself Floating Point" class implements a floating-point number +// with a uint64 significand and an int exponent. Normalized DiyFp numbers will +// have the most significant bit of the significand set. +// Multiplication and Subtraction do not normalize their results. +// DiyFp are not designed to contain special doubles (NaN and Infinity). +class DiyFp { + public: + static const int kSignificandSize = 64; + + DiyFp() : f_(0), e_(0) {} + DiyFp(uint64_t f, int e) : f_(f), e_(e) {} + + // this = this - other. + // The exponents of both numbers must be the same and the significand of this + // must be bigger than the significand of other. + // The result will not be normalized. + void Subtract(const DiyFp& other) { + ASSERT(e_ == other.e_); + ASSERT(f_ >= other.f_); + f_ -= other.f_; + } + + // Returns a - b. + // The exponents of both numbers must be the same and this must be bigger + // than other. The result will not be normalized. + static DiyFp Minus(const DiyFp& a, const DiyFp& b) { + DiyFp result = a; + result.Subtract(b); + return result; + } + + + // this = this * other. + void Multiply(const DiyFp& other); + + // returns a * b; + static DiyFp Times(const DiyFp& a, const DiyFp& b) { + DiyFp result = a; + result.Multiply(b); + return result; + } + + void Normalize() { + ASSERT(f_ != 0); + uint64_t f = f_; + int e = e_; + + // This method is mainly called for normalizing boundaries. In general + // boundaries need to be shifted by 10 bits. We thus optimize for this case. + const uint64_t k10MSBits = UINT64_2PART_C(0xFFC00000, 00000000); + while ((f & k10MSBits) == 0) { + f <<= 10; + e -= 10; + } + while ((f & kUint64MSB) == 0) { + f <<= 1; + e--; + } + f_ = f; + e_ = e; + } + + static DiyFp Normalize(const DiyFp& a) { + DiyFp result = a; + result.Normalize(); + return result; + } + + uint64_t f() const { return f_; } + int e() const { return e_; } + + void set_f(uint64_t new_value) { f_ = new_value; } + void set_e(int new_value) { e_ = new_value; } + + private: + static const uint64_t kUint64MSB = UINT64_2PART_C(0x80000000, 00000000); + + uint64_t f_; + int e_; +}; + +} // namespace double_conversion + +#endif // DOUBLE_CONVERSION_DIY_FP_H_ diff --git a/mfbt/double-conversion/double-conversion.cc b/mfbt/double-conversion/double-conversion.cc new file mode 100644 index 000000000..394b6a053 --- /dev/null +++ b/mfbt/double-conversion/double-conversion.cc @@ -0,0 +1,892 @@ +// Copyright 2010 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#include <limits.h> +#include <math.h> + +#include "double-conversion.h" + +#include "bignum-dtoa.h" +#include "fast-dtoa.h" +#include "fixed-dtoa.h" +#include "ieee.h" +#include "strtod.h" +#include "utils.h" + +namespace double_conversion { + +const DoubleToStringConverter& DoubleToStringConverter::EcmaScriptConverter() { + int flags = UNIQUE_ZERO | EMIT_POSITIVE_EXPONENT_SIGN; + static DoubleToStringConverter converter(flags, + "Infinity", + "NaN", + 'e', + -6, 21, + 6, 0); + return converter; +} + + +bool DoubleToStringConverter::HandleSpecialValues( + double value, + StringBuilder* result_builder) const { + Double double_inspect(value); + if (double_inspect.IsInfinite()) { + if (infinity_symbol_ == NULL) return false; + if (value < 0) { + result_builder->AddCharacter('-'); + } + result_builder->AddString(infinity_symbol_); + return true; + } + if (double_inspect.IsNan()) { + if (nan_symbol_ == NULL) return false; + result_builder->AddString(nan_symbol_); + return true; + } + return false; +} + + +void DoubleToStringConverter::CreateExponentialRepresentation( + const char* decimal_digits, + int length, + int exponent, + StringBuilder* result_builder) const { + ASSERT(length != 0); + result_builder->AddCharacter(decimal_digits[0]); + if (length != 1) { + result_builder->AddCharacter('.'); + result_builder->AddSubstring(&decimal_digits[1], length-1); + } + result_builder->AddCharacter(exponent_character_); + if (exponent < 0) { + result_builder->AddCharacter('-'); + exponent = -exponent; + } else { + if ((flags_ & EMIT_POSITIVE_EXPONENT_SIGN) != 0) { + result_builder->AddCharacter('+'); + } + } + if (exponent == 0) { + result_builder->AddCharacter('0'); + return; + } + ASSERT(exponent < 1e4); + const int kMaxExponentLength = 5; + char buffer[kMaxExponentLength + 1]; + buffer[kMaxExponentLength] = '\0'; + int first_char_pos = kMaxExponentLength; + while (exponent > 0) { + buffer[--first_char_pos] = '0' + (exponent % 10); + exponent /= 10; + } + result_builder->AddSubstring(&buffer[first_char_pos], + kMaxExponentLength - first_char_pos); +} + + +void DoubleToStringConverter::CreateDecimalRepresentation( + const char* decimal_digits, + int length, + int decimal_point, + int digits_after_point, + StringBuilder* result_builder) const { + // Create a representation that is padded with zeros if needed. + if (decimal_point <= 0) { + // "0.00000decimal_rep". + result_builder->AddCharacter('0'); + if (digits_after_point > 0) { + result_builder->AddCharacter('.'); + result_builder->AddPadding('0', -decimal_point); + ASSERT(length <= digits_after_point - (-decimal_point)); + result_builder->AddSubstring(decimal_digits, length); + int remaining_digits = digits_after_point - (-decimal_point) - length; + result_builder->AddPadding('0', remaining_digits); + } + } else if (decimal_point >= length) { + // "decimal_rep0000.00000" or "decimal_rep.0000" + result_builder->AddSubstring(decimal_digits, length); + result_builder->AddPadding('0', decimal_point - length); + if (digits_after_point > 0) { + result_builder->AddCharacter('.'); + result_builder->AddPadding('0', digits_after_point); + } + } else { + // "decima.l_rep000" + ASSERT(digits_after_point > 0); + result_builder->AddSubstring(decimal_digits, decimal_point); + result_builder->AddCharacter('.'); + ASSERT(length - decimal_point <= digits_after_point); + result_builder->AddSubstring(&decimal_digits[decimal_point], + length - decimal_point); + int remaining_digits = digits_after_point - (length - decimal_point); + result_builder->AddPadding('0', remaining_digits); + } + if (digits_after_point == 0) { + if ((flags_ & EMIT_TRAILING_DECIMAL_POINT) != 0) { + result_builder->AddCharacter('.'); + } + if ((flags_ & EMIT_TRAILING_ZERO_AFTER_POINT) != 0) { + result_builder->AddCharacter('0'); + } + } +} + + +bool DoubleToStringConverter::ToShortestIeeeNumber( + double value, + StringBuilder* result_builder, + DoubleToStringConverter::DtoaMode mode) const { + ASSERT(mode == SHORTEST || mode == SHORTEST_SINGLE); + if (Double(value).IsSpecial()) { + return HandleSpecialValues(value, result_builder); + } + + int decimal_point; + bool sign; + const int kDecimalRepCapacity = kBase10MaximalLength + 1; + char decimal_rep[kDecimalRepCapacity]; + int decimal_rep_length; + + DoubleToAscii(value, mode, 0, decimal_rep, kDecimalRepCapacity, + &sign, &decimal_rep_length, &decimal_point); + + bool unique_zero = (flags_ & UNIQUE_ZERO) != 0; + if (sign && (value != 0.0 || !unique_zero)) { + result_builder->AddCharacter('-'); + } + + int exponent = decimal_point - 1; + if ((decimal_in_shortest_low_ <= exponent) && + (exponent < decimal_in_shortest_high_)) { + CreateDecimalRepresentation(decimal_rep, decimal_rep_length, + decimal_point, + Max(0, decimal_rep_length - decimal_point), + result_builder); + } else { + CreateExponentialRepresentation(decimal_rep, decimal_rep_length, exponent, + result_builder); + } + return true; +} + + +bool DoubleToStringConverter::ToFixed(double value, + int requested_digits, + StringBuilder* result_builder) const { + ASSERT(kMaxFixedDigitsBeforePoint == 60); + const double kFirstNonFixed = 1e60; + + if (Double(value).IsSpecial()) { + return HandleSpecialValues(value, result_builder); + } + + if (requested_digits > kMaxFixedDigitsAfterPoint) return false; + if (value >= kFirstNonFixed || value <= -kFirstNonFixed) return false; + + // Find a sufficiently precise decimal representation of n. + int decimal_point; + bool sign; + // Add space for the '\0' byte. + const int kDecimalRepCapacity = + kMaxFixedDigitsBeforePoint + kMaxFixedDigitsAfterPoint + 1; + char decimal_rep[kDecimalRepCapacity]; + int decimal_rep_length; + DoubleToAscii(value, FIXED, requested_digits, + decimal_rep, kDecimalRepCapacity, + &sign, &decimal_rep_length, &decimal_point); + + bool unique_zero = ((flags_ & UNIQUE_ZERO) != 0); + if (sign && (value != 0.0 || !unique_zero)) { + result_builder->AddCharacter('-'); + } + + CreateDecimalRepresentation(decimal_rep, decimal_rep_length, decimal_point, + requested_digits, result_builder); + return true; +} + + +bool DoubleToStringConverter::ToExponential( + double value, + int requested_digits, + StringBuilder* result_builder) const { + if (Double(value).IsSpecial()) { + return HandleSpecialValues(value, result_builder); + } + + if (requested_digits < -1) return false; + if (requested_digits > kMaxExponentialDigits) return false; + + int decimal_point; + bool sign; + // Add space for digit before the decimal point and the '\0' character. + const int kDecimalRepCapacity = kMaxExponentialDigits + 2; + ASSERT(kDecimalRepCapacity > kBase10MaximalLength); + char decimal_rep[kDecimalRepCapacity]; + int decimal_rep_length; + + if (requested_digits == -1) { + DoubleToAscii(value, SHORTEST, 0, + decimal_rep, kDecimalRepCapacity, + &sign, &decimal_rep_length, &decimal_point); + } else { + DoubleToAscii(value, PRECISION, requested_digits + 1, + decimal_rep, kDecimalRepCapacity, + &sign, &decimal_rep_length, &decimal_point); + ASSERT(decimal_rep_length <= requested_digits + 1); + + for (int i = decimal_rep_length; i < requested_digits + 1; ++i) { + decimal_rep[i] = '0'; + } + decimal_rep_length = requested_digits + 1; + } + + bool unique_zero = ((flags_ & UNIQUE_ZERO) != 0); + if (sign && (value != 0.0 || !unique_zero)) { + result_builder->AddCharacter('-'); + } + + int exponent = decimal_point - 1; + CreateExponentialRepresentation(decimal_rep, + decimal_rep_length, + exponent, + result_builder); + return true; +} + + +bool DoubleToStringConverter::ToPrecision(double value, + int precision, + bool* used_exponential_notation, + StringBuilder* result_builder) const { + *used_exponential_notation = false; + if (Double(value).IsSpecial()) { + return HandleSpecialValues(value, result_builder); + } + + if (precision < kMinPrecisionDigits || precision > kMaxPrecisionDigits) { + return false; + } + + // Find a sufficiently precise decimal representation of n. + int decimal_point; + bool sign; + // Add one for the terminating null character. + const int kDecimalRepCapacity = kMaxPrecisionDigits + 1; + char decimal_rep[kDecimalRepCapacity]; + int decimal_rep_length; + + DoubleToAscii(value, PRECISION, precision, + decimal_rep, kDecimalRepCapacity, + &sign, &decimal_rep_length, &decimal_point); + ASSERT(decimal_rep_length <= precision); + + bool unique_zero = ((flags_ & UNIQUE_ZERO) != 0); + if (sign && (value != 0.0 || !unique_zero)) { + result_builder->AddCharacter('-'); + } + + // The exponent if we print the number as x.xxeyyy. That is with the + // decimal point after the first digit. + int exponent = decimal_point - 1; + + int extra_zero = ((flags_ & EMIT_TRAILING_ZERO_AFTER_POINT) != 0) ? 1 : 0; + if ((-decimal_point + 1 > max_leading_padding_zeroes_in_precision_mode_) || + (decimal_point - precision + extra_zero > + max_trailing_padding_zeroes_in_precision_mode_)) { + // Fill buffer to contain 'precision' digits. + // Usually the buffer is already at the correct length, but 'DoubleToAscii' + // is allowed to return less characters. + for (int i = decimal_rep_length; i < precision; ++i) { + decimal_rep[i] = '0'; + } + + *used_exponential_notation = true; + CreateExponentialRepresentation(decimal_rep, + precision, + exponent, + result_builder); + } else { + CreateDecimalRepresentation(decimal_rep, decimal_rep_length, decimal_point, + Max(0, precision - decimal_point), + result_builder); + } + return true; +} + + +static BignumDtoaMode DtoaToBignumDtoaMode( + DoubleToStringConverter::DtoaMode dtoa_mode) { + switch (dtoa_mode) { + case DoubleToStringConverter::SHORTEST: return BIGNUM_DTOA_SHORTEST; + case DoubleToStringConverter::SHORTEST_SINGLE: + return BIGNUM_DTOA_SHORTEST_SINGLE; + case DoubleToStringConverter::FIXED: return BIGNUM_DTOA_FIXED; + case DoubleToStringConverter::PRECISION: return BIGNUM_DTOA_PRECISION; + default: + UNREACHABLE(); + return BIGNUM_DTOA_SHORTEST; // To silence compiler. + } +} + + +void DoubleToStringConverter::DoubleToAscii(double v, + DtoaMode mode, + int requested_digits, + char* buffer, + int buffer_length, + bool* sign, + int* length, + int* point) { + Vector<char> vector(buffer, buffer_length); + ASSERT(!Double(v).IsSpecial()); + ASSERT(mode == SHORTEST || mode == SHORTEST_SINGLE || requested_digits >= 0); + + if (Double(v).Sign() < 0) { + *sign = true; + v = -v; + } else { + *sign = false; + } + + if (mode == PRECISION && requested_digits == 0) { + vector[0] = '\0'; + *length = 0; + return; + } + + if (v == 0) { + vector[0] = '0'; + vector[1] = '\0'; + *length = 1; + *point = 1; + return; + } + + bool fast_worked; + switch (mode) { + case SHORTEST: + fast_worked = FastDtoa(v, FAST_DTOA_SHORTEST, 0, vector, length, point); + break; + case SHORTEST_SINGLE: + fast_worked = FastDtoa(v, FAST_DTOA_SHORTEST_SINGLE, 0, + vector, length, point); + break; + case FIXED: + fast_worked = FastFixedDtoa(v, requested_digits, vector, length, point); + break; + case PRECISION: + fast_worked = FastDtoa(v, FAST_DTOA_PRECISION, requested_digits, + vector, length, point); + break; + default: + UNREACHABLE(); + fast_worked = false; + } + if (fast_worked) return; + + // If the fast dtoa didn't succeed use the slower bignum version. + BignumDtoaMode bignum_mode = DtoaToBignumDtoaMode(mode); + BignumDtoa(v, bignum_mode, requested_digits, vector, length, point); + vector[*length] = '\0'; +} + + +// Consumes the given substring from the iterator. +// Returns false, if the substring does not match. +static bool ConsumeSubString(const char** current, + const char* end, + const char* substring) { + ASSERT(**current == *substring); + for (substring++; *substring != '\0'; substring++) { + ++*current; + if (*current == end || **current != *substring) return false; + } + ++*current; + return true; +} + + +// Maximum number of significant digits in decimal representation. +// The longest possible double in decimal representation is +// (2^53 - 1) * 2 ^ -1074 that is (2 ^ 53 - 1) * 5 ^ 1074 / 10 ^ 1074 +// (768 digits). If we parse a number whose first digits are equal to a +// mean of 2 adjacent doubles (that could have up to 769 digits) the result +// must be rounded to the bigger one unless the tail consists of zeros, so +// we don't need to preserve all the digits. +const int kMaxSignificantDigits = 772; + + +// Returns true if a nonspace found and false if the end has reached. +static inline bool AdvanceToNonspace(const char** current, const char* end) { + while (*current != end) { + if (**current != ' ') return true; + ++*current; + } + return false; +} + + +static bool isDigit(int x, int radix) { + return (x >= '0' && x <= '9' && x < '0' + radix) + || (radix > 10 && x >= 'a' && x < 'a' + radix - 10) + || (radix > 10 && x >= 'A' && x < 'A' + radix - 10); +} + + +static double SignedZero(bool sign) { + return sign ? -0.0 : 0.0; +} + + +// Parsing integers with radix 2, 4, 8, 16, 32. Assumes current != end. +template <int radix_log_2> +static double RadixStringToIeee(const char* current, + const char* end, + bool sign, + bool allow_trailing_junk, + double junk_string_value, + bool read_as_double, + const char** trailing_pointer) { + ASSERT(current != end); + + const int kDoubleSize = Double::kSignificandSize; + const int kSingleSize = Single::kSignificandSize; + const int kSignificandSize = read_as_double? kDoubleSize: kSingleSize; + + // Skip leading 0s. + while (*current == '0') { + ++current; + if (current == end) { + *trailing_pointer = end; + return SignedZero(sign); + } + } + + int64_t number = 0; + int exponent = 0; + const int radix = (1 << radix_log_2); + + do { + int digit; + if (*current >= '0' && *current <= '9' && *current < '0' + radix) { + digit = static_cast<char>(*current) - '0'; + } else if (radix > 10 && *current >= 'a' && *current < 'a' + radix - 10) { + digit = static_cast<char>(*current) - 'a' + 10; + } else if (radix > 10 && *current >= 'A' && *current < 'A' + radix - 10) { + digit = static_cast<char>(*current) - 'A' + 10; + } else { + if (allow_trailing_junk || !AdvanceToNonspace(¤t, end)) { + break; + } else { + return junk_string_value; + } + } + + number = number * radix + digit; + int overflow = static_cast<int>(number >> kSignificandSize); + if (overflow != 0) { + // Overflow occurred. Need to determine which direction to round the + // result. + int overflow_bits_count = 1; + while (overflow > 1) { + overflow_bits_count++; + overflow >>= 1; + } + + int dropped_bits_mask = ((1 << overflow_bits_count) - 1); + int dropped_bits = static_cast<int>(number) & dropped_bits_mask; + number >>= overflow_bits_count; + exponent = overflow_bits_count; + + bool zero_tail = true; + while (true) { + ++current; + if (current == end || !isDigit(*current, radix)) break; + zero_tail = zero_tail && *current == '0'; + exponent += radix_log_2; + } + + if (!allow_trailing_junk && AdvanceToNonspace(¤t, end)) { + return junk_string_value; + } + + int middle_value = (1 << (overflow_bits_count - 1)); + if (dropped_bits > middle_value) { + number++; // Rounding up. + } else if (dropped_bits == middle_value) { + // Rounding to even to consistency with decimals: half-way case rounds + // up if significant part is odd and down otherwise. + if ((number & 1) != 0 || !zero_tail) { + number++; // Rounding up. + } + } + + // Rounding up may cause overflow. + if ((number & ((int64_t)1 << kSignificandSize)) != 0) { + exponent++; + number >>= 1; + } + break; + } + ++current; + } while (current != end); + + ASSERT(number < ((int64_t)1 << kSignificandSize)); + ASSERT(static_cast<int64_t>(static_cast<double>(number)) == number); + + *trailing_pointer = current; + + if (exponent == 0) { + if (sign) { + if (number == 0) return -0.0; + number = -number; + } + return static_cast<double>(number); + } + + ASSERT(number != 0); + return Double(DiyFp(number, exponent)).value(); +} + + +double StringToDoubleConverter::StringToIeee( + const char* input, + int length, + int* processed_characters_count, + bool read_as_double) const { + const char* current = input; + const char* end = input + length; + + *processed_characters_count = 0; + + const bool allow_trailing_junk = (flags_ & ALLOW_TRAILING_JUNK) != 0; + const bool allow_leading_spaces = (flags_ & ALLOW_LEADING_SPACES) != 0; + const bool allow_trailing_spaces = (flags_ & ALLOW_TRAILING_SPACES) != 0; + const bool allow_spaces_after_sign = (flags_ & ALLOW_SPACES_AFTER_SIGN) != 0; + + // To make sure that iterator dereferencing is valid the following + // convention is used: + // 1. Each '++current' statement is followed by check for equality to 'end'. + // 2. If AdvanceToNonspace returned false then current == end. + // 3. If 'current' becomes equal to 'end' the function returns or goes to + // 'parsing_done'. + // 4. 'current' is not dereferenced after the 'parsing_done' label. + // 5. Code before 'parsing_done' may rely on 'current != end'. + if (current == end) return empty_string_value_; + + if (allow_leading_spaces || allow_trailing_spaces) { + if (!AdvanceToNonspace(¤t, end)) { + *processed_characters_count = current - input; + return empty_string_value_; + } + if (!allow_leading_spaces && (input != current)) { + // No leading spaces allowed, but AdvanceToNonspace moved forward. + return junk_string_value_; + } + } + + // The longest form of simplified number is: "-<significant digits>.1eXXX\0". + const int kBufferSize = kMaxSignificantDigits + 10; + char buffer[kBufferSize]; // NOLINT: size is known at compile time. + int buffer_pos = 0; + + // Exponent will be adjusted if insignificant digits of the integer part + // or insignificant leading zeros of the fractional part are dropped. + int exponent = 0; + int significant_digits = 0; + int insignificant_digits = 0; + bool nonzero_digit_dropped = false; + + bool sign = false; + + if (*current == '+' || *current == '-') { + sign = (*current == '-'); + ++current; + const char* next_non_space = current; + // Skip following spaces (if allowed). + if (!AdvanceToNonspace(&next_non_space, end)) return junk_string_value_; + if (!allow_spaces_after_sign && (current != next_non_space)) { + return junk_string_value_; + } + current = next_non_space; + } + + if (infinity_symbol_ != NULL) { + if (*current == infinity_symbol_[0]) { + if (!ConsumeSubString(¤t, end, infinity_symbol_)) { + return junk_string_value_; + } + + if (!(allow_trailing_spaces || allow_trailing_junk) && (current != end)) { + return junk_string_value_; + } + if (!allow_trailing_junk && AdvanceToNonspace(¤t, end)) { + return junk_string_value_; + } + + ASSERT(buffer_pos == 0); + *processed_characters_count = current - input; + return sign ? -Double::Infinity() : Double::Infinity(); + } + } + + if (nan_symbol_ != NULL) { + if (*current == nan_symbol_[0]) { + if (!ConsumeSubString(¤t, end, nan_symbol_)) { + return junk_string_value_; + } + + if (!(allow_trailing_spaces || allow_trailing_junk) && (current != end)) { + return junk_string_value_; + } + if (!allow_trailing_junk && AdvanceToNonspace(¤t, end)) { + return junk_string_value_; + } + + ASSERT(buffer_pos == 0); + *processed_characters_count = current - input; + return sign ? -Double::NaN() : Double::NaN(); + } + } + + bool leading_zero = false; + if (*current == '0') { + ++current; + if (current == end) { + *processed_characters_count = current - input; + return SignedZero(sign); + } + + leading_zero = true; + + // It could be hexadecimal value. + if ((flags_ & ALLOW_HEX) && (*current == 'x' || *current == 'X')) { + ++current; + if (current == end || !isDigit(*current, 16)) { + return junk_string_value_; // "0x". + } + + const char* tail_pointer = NULL; + double result = RadixStringToIeee<4>(current, + end, + sign, + allow_trailing_junk, + junk_string_value_, + read_as_double, + &tail_pointer); + if (tail_pointer != NULL) { + if (allow_trailing_spaces) AdvanceToNonspace(&tail_pointer, end); + *processed_characters_count = tail_pointer - input; + } + return result; + } + + // Ignore leading zeros in the integer part. + while (*current == '0') { + ++current; + if (current == end) { + *processed_characters_count = current - input; + return SignedZero(sign); + } + } + } + + bool octal = leading_zero && (flags_ & ALLOW_OCTALS) != 0; + + // Copy significant digits of the integer part (if any) to the buffer. + while (*current >= '0' && *current <= '9') { + if (significant_digits < kMaxSignificantDigits) { + ASSERT(buffer_pos < kBufferSize); + buffer[buffer_pos++] = static_cast<char>(*current); + significant_digits++; + // Will later check if it's an octal in the buffer. + } else { + insignificant_digits++; // Move the digit into the exponential part. + nonzero_digit_dropped = nonzero_digit_dropped || *current != '0'; + } + octal = octal && *current < '8'; + ++current; + if (current == end) goto parsing_done; + } + + if (significant_digits == 0) { + octal = false; + } + + if (*current == '.') { + if (octal && !allow_trailing_junk) return junk_string_value_; + if (octal) goto parsing_done; + + ++current; + if (current == end) { + if (significant_digits == 0 && !leading_zero) { + return junk_string_value_; + } else { + goto parsing_done; + } + } + + if (significant_digits == 0) { + // octal = false; + // Integer part consists of 0 or is absent. Significant digits start after + // leading zeros (if any). + while (*current == '0') { + ++current; + if (current == end) { + *processed_characters_count = current - input; + return SignedZero(sign); + } + exponent--; // Move this 0 into the exponent. + } + } + + // There is a fractional part. + // We don't emit a '.', but adjust the exponent instead. + while (*current >= '0' && *current <= '9') { + if (significant_digits < kMaxSignificantDigits) { + ASSERT(buffer_pos < kBufferSize); + buffer[buffer_pos++] = static_cast<char>(*current); + significant_digits++; + exponent--; + } else { + // Ignore insignificant digits in the fractional part. + nonzero_digit_dropped = nonzero_digit_dropped || *current != '0'; + } + ++current; + if (current == end) goto parsing_done; + } + } + + if (!leading_zero && exponent == 0 && significant_digits == 0) { + // If leading_zeros is true then the string contains zeros. + // If exponent < 0 then string was [+-]\.0*... + // If significant_digits != 0 the string is not equal to 0. + // Otherwise there are no digits in the string. + return junk_string_value_; + } + + // Parse exponential part. + if (*current == 'e' || *current == 'E') { + if (octal && !allow_trailing_junk) return junk_string_value_; + if (octal) goto parsing_done; + ++current; + if (current == end) { + if (allow_trailing_junk) { + goto parsing_done; + } else { + return junk_string_value_; + } + } + char sign = '+'; + if (*current == '+' || *current == '-') { + sign = static_cast<char>(*current); + ++current; + if (current == end) { + if (allow_trailing_junk) { + goto parsing_done; + } else { + return junk_string_value_; + } + } + } + + if (current == end || *current < '0' || *current > '9') { + if (allow_trailing_junk) { + goto parsing_done; + } else { + return junk_string_value_; + } + } + + const int max_exponent = INT_MAX / 2; + ASSERT(-max_exponent / 2 <= exponent && exponent <= max_exponent / 2); + int num = 0; + do { + // Check overflow. + int digit = *current - '0'; + if (num >= max_exponent / 10 + && !(num == max_exponent / 10 && digit <= max_exponent % 10)) { + num = max_exponent; + } else { + num = num * 10 + digit; + } + ++current; + } while (current != end && *current >= '0' && *current <= '9'); + + exponent += (sign == '-' ? -num : num); + } + + if (!(allow_trailing_spaces || allow_trailing_junk) && (current != end)) { + return junk_string_value_; + } + if (!allow_trailing_junk && AdvanceToNonspace(¤t, end)) { + return junk_string_value_; + } + if (allow_trailing_spaces) { + AdvanceToNonspace(¤t, end); + } + + parsing_done: + exponent += insignificant_digits; + + if (octal) { + double result; + const char* tail_pointer = NULL; + result = RadixStringToIeee<3>(buffer, + buffer + buffer_pos, + sign, + allow_trailing_junk, + junk_string_value_, + read_as_double, + &tail_pointer); + ASSERT(tail_pointer != NULL); + *processed_characters_count = current - input; + return result; + } + + if (nonzero_digit_dropped) { + buffer[buffer_pos++] = '1'; + exponent--; + } + + ASSERT(buffer_pos < kBufferSize); + buffer[buffer_pos] = '\0'; + + double converted; + if (read_as_double) { + converted = Strtod(Vector<const char>(buffer, buffer_pos), exponent); + } else { + converted = Strtof(Vector<const char>(buffer, buffer_pos), exponent); + } + *processed_characters_count = current - input; + return sign? -converted: converted; +} + +} // namespace double_conversion diff --git a/mfbt/double-conversion/double-conversion.h b/mfbt/double-conversion/double-conversion.h new file mode 100644 index 000000000..957575cfb --- /dev/null +++ b/mfbt/double-conversion/double-conversion.h @@ -0,0 +1,538 @@ +// Copyright 2012 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#ifndef DOUBLE_CONVERSION_DOUBLE_CONVERSION_H_ +#define DOUBLE_CONVERSION_DOUBLE_CONVERSION_H_ + +#include "mozilla/Types.h" +#include "utils.h" + +namespace double_conversion { + +class DoubleToStringConverter { + public: + // When calling ToFixed with a double > 10^kMaxFixedDigitsBeforePoint + // or a requested_digits parameter > kMaxFixedDigitsAfterPoint then the + // function returns false. + static const int kMaxFixedDigitsBeforePoint = 60; + static const int kMaxFixedDigitsAfterPoint = 60; + + // When calling ToExponential with a requested_digits + // parameter > kMaxExponentialDigits then the function returns false. + static const int kMaxExponentialDigits = 120; + + // When calling ToPrecision with a requested_digits + // parameter < kMinPrecisionDigits or requested_digits > kMaxPrecisionDigits + // then the function returns false. + static const int kMinPrecisionDigits = 1; + static const int kMaxPrecisionDigits = 120; + + enum Flags { + NO_FLAGS = 0, + EMIT_POSITIVE_EXPONENT_SIGN = 1, + EMIT_TRAILING_DECIMAL_POINT = 2, + EMIT_TRAILING_ZERO_AFTER_POINT = 4, + UNIQUE_ZERO = 8 + }; + + // Flags should be a bit-or combination of the possible Flags-enum. + // - NO_FLAGS: no special flags. + // - EMIT_POSITIVE_EXPONENT_SIGN: when the number is converted into exponent + // form, emits a '+' for positive exponents. Example: 1.2e+2. + // - EMIT_TRAILING_DECIMAL_POINT: when the input number is an integer and is + // converted into decimal format then a trailing decimal point is appended. + // Example: 2345.0 is converted to "2345.". + // - EMIT_TRAILING_ZERO_AFTER_POINT: in addition to a trailing decimal point + // emits a trailing '0'-character. This flag requires the + // EXMIT_TRAILING_DECIMAL_POINT flag. + // Example: 2345.0 is converted to "2345.0". + // - UNIQUE_ZERO: "-0.0" is converted to "0.0". + // + // Infinity symbol and nan_symbol provide the string representation for these + // special values. If the string is NULL and the special value is encountered + // then the conversion functions return false. + // + // The exponent_character is used in exponential representations. It is + // usually 'e' or 'E'. + // + // When converting to the shortest representation the converter will + // represent input numbers in decimal format if they are in the interval + // [10^decimal_in_shortest_low; 10^decimal_in_shortest_high[ + // (lower boundary included, greater boundary excluded). + // Example: with decimal_in_shortest_low = -6 and + // decimal_in_shortest_high = 21: + // ToShortest(0.000001) -> "0.000001" + // ToShortest(0.0000001) -> "1e-7" + // ToShortest(111111111111111111111.0) -> "111111111111111110000" + // ToShortest(100000000000000000000.0) -> "100000000000000000000" + // ToShortest(1111111111111111111111.0) -> "1.1111111111111111e+21" + // + // When converting to precision mode the converter may add + // max_leading_padding_zeroes before returning the number in exponential + // format. + // Example with max_leading_padding_zeroes_in_precision_mode = 6. + // ToPrecision(0.0000012345, 2) -> "0.0000012" + // ToPrecision(0.00000012345, 2) -> "1.2e-7" + // Similarily the converter may add up to + // max_trailing_padding_zeroes_in_precision_mode in precision mode to avoid + // returning an exponential representation. A zero added by the + // EMIT_TRAILING_ZERO_AFTER_POINT flag is counted for this limit. + // Examples for max_trailing_padding_zeroes_in_precision_mode = 1: + // ToPrecision(230.0, 2) -> "230" + // ToPrecision(230.0, 2) -> "230." with EMIT_TRAILING_DECIMAL_POINT. + // ToPrecision(230.0, 2) -> "2.3e2" with EMIT_TRAILING_ZERO_AFTER_POINT. + DoubleToStringConverter(int flags, + const char* infinity_symbol, + const char* nan_symbol, + char exponent_character, + int decimal_in_shortest_low, + int decimal_in_shortest_high, + int max_leading_padding_zeroes_in_precision_mode, + int max_trailing_padding_zeroes_in_precision_mode) + : flags_(flags), + infinity_symbol_(infinity_symbol), + nan_symbol_(nan_symbol), + exponent_character_(exponent_character), + decimal_in_shortest_low_(decimal_in_shortest_low), + decimal_in_shortest_high_(decimal_in_shortest_high), + max_leading_padding_zeroes_in_precision_mode_( + max_leading_padding_zeroes_in_precision_mode), + max_trailing_padding_zeroes_in_precision_mode_( + max_trailing_padding_zeroes_in_precision_mode) { + // When 'trailing zero after the point' is set, then 'trailing point' + // must be set too. + ASSERT(((flags & EMIT_TRAILING_DECIMAL_POINT) != 0) || + !((flags & EMIT_TRAILING_ZERO_AFTER_POINT) != 0)); + } + + // Returns a converter following the EcmaScript specification. + static MFBT_API const DoubleToStringConverter& EcmaScriptConverter(); + + // Computes the shortest string of digits that correctly represent the input + // number. Depending on decimal_in_shortest_low and decimal_in_shortest_high + // (see constructor) it then either returns a decimal representation, or an + // exponential representation. + // Example with decimal_in_shortest_low = -6, + // decimal_in_shortest_high = 21, + // EMIT_POSITIVE_EXPONENT_SIGN activated, and + // EMIT_TRAILING_DECIMAL_POINT deactived: + // ToShortest(0.000001) -> "0.000001" + // ToShortest(0.0000001) -> "1e-7" + // ToShortest(111111111111111111111.0) -> "111111111111111110000" + // ToShortest(100000000000000000000.0) -> "100000000000000000000" + // ToShortest(1111111111111111111111.0) -> "1.1111111111111111e+21" + // + // Note: the conversion may round the output if the returned string + // is accurate enough to uniquely identify the input-number. + // For example the most precise representation of the double 9e59 equals + // "899999999999999918767229449717619953810131273674690656206848", but + // the converter will return the shorter (but still correct) "9e59". + // + // Returns true if the conversion succeeds. The conversion always succeeds + // except when the input value is special and no infinity_symbol or + // nan_symbol has been given to the constructor. + bool ToShortest(double value, StringBuilder* result_builder) const { + return ToShortestIeeeNumber(value, result_builder, SHORTEST); + } + + // Same as ToShortest, but for single-precision floats. + bool ToShortestSingle(float value, StringBuilder* result_builder) const { + return ToShortestIeeeNumber(value, result_builder, SHORTEST_SINGLE); + } + + + // Computes a decimal representation with a fixed number of digits after the + // decimal point. The last emitted digit is rounded. + // + // Examples: + // ToFixed(3.12, 1) -> "3.1" + // ToFixed(3.1415, 3) -> "3.142" + // ToFixed(1234.56789, 4) -> "1234.5679" + // ToFixed(1.23, 5) -> "1.23000" + // ToFixed(0.1, 4) -> "0.1000" + // ToFixed(1e30, 2) -> "1000000000000000019884624838656.00" + // ToFixed(0.1, 30) -> "0.100000000000000005551115123126" + // ToFixed(0.1, 17) -> "0.10000000000000001" + // + // If requested_digits equals 0, then the tail of the result depends on + // the EMIT_TRAILING_DECIMAL_POINT and EMIT_TRAILING_ZERO_AFTER_POINT. + // Examples, for requested_digits == 0, + // let EMIT_TRAILING_DECIMAL_POINT and EMIT_TRAILING_ZERO_AFTER_POINT be + // - false and false: then 123.45 -> 123 + // 0.678 -> 1 + // - true and false: then 123.45 -> 123. + // 0.678 -> 1. + // - true and true: then 123.45 -> 123.0 + // 0.678 -> 1.0 + // + // Returns true if the conversion succeeds. The conversion always succeeds + // except for the following cases: + // - the input value is special and no infinity_symbol or nan_symbol has + // been provided to the constructor, + // - 'value' > 10^kMaxFixedDigitsBeforePoint, or + // - 'requested_digits' > kMaxFixedDigitsAfterPoint. + // The last two conditions imply that the result will never contain more than + // 1 + kMaxFixedDigitsBeforePoint + 1 + kMaxFixedDigitsAfterPoint characters + // (one additional character for the sign, and one for the decimal point). + MFBT_API bool ToFixed(double value, + int requested_digits, + StringBuilder* result_builder) const; + + // Computes a representation in exponential format with requested_digits + // after the decimal point. The last emitted digit is rounded. + // If requested_digits equals -1, then the shortest exponential representation + // is computed. + // + // Examples with EMIT_POSITIVE_EXPONENT_SIGN deactivated, and + // exponent_character set to 'e'. + // ToExponential(3.12, 1) -> "3.1e0" + // ToExponential(5.0, 3) -> "5.000e0" + // ToExponential(0.001, 2) -> "1.00e-3" + // ToExponential(3.1415, -1) -> "3.1415e0" + // ToExponential(3.1415, 4) -> "3.1415e0" + // ToExponential(3.1415, 3) -> "3.142e0" + // ToExponential(123456789000000, 3) -> "1.235e14" + // ToExponential(1000000000000000019884624838656.0, -1) -> "1e30" + // ToExponential(1000000000000000019884624838656.0, 32) -> + // "1.00000000000000001988462483865600e30" + // ToExponential(1234, 0) -> "1e3" + // + // Returns true if the conversion succeeds. The conversion always succeeds + // except for the following cases: + // - the input value is special and no infinity_symbol or nan_symbol has + // been provided to the constructor, + // - 'requested_digits' > kMaxExponentialDigits. + // The last condition implies that the result will never contain more than + // kMaxExponentialDigits + 8 characters (the sign, the digit before the + // decimal point, the decimal point, the exponent character, the + // exponent's sign, and at most 3 exponent digits). + MFBT_API bool ToExponential(double value, + int requested_digits, + StringBuilder* result_builder) const; + + // Computes 'precision' leading digits of the given 'value' and returns them + // either in exponential or decimal format, depending on + // max_{leading|trailing}_padding_zeroes_in_precision_mode (given to the + // constructor). + // The last computed digit is rounded. + // + // Example with max_leading_padding_zeroes_in_precision_mode = 6. + // ToPrecision(0.0000012345, 2) -> "0.0000012" + // ToPrecision(0.00000012345, 2) -> "1.2e-7" + // Similarily the converter may add up to + // max_trailing_padding_zeroes_in_precision_mode in precision mode to avoid + // returning an exponential representation. A zero added by the + // EMIT_TRAILING_ZERO_AFTER_POINT flag is counted for this limit. + // Examples for max_trailing_padding_zeroes_in_precision_mode = 1: + // ToPrecision(230.0, 2) -> "230" + // ToPrecision(230.0, 2) -> "230." with EMIT_TRAILING_DECIMAL_POINT. + // ToPrecision(230.0, 2) -> "2.3e2" with EMIT_TRAILING_ZERO_AFTER_POINT. + // Examples for max_trailing_padding_zeroes_in_precision_mode = 3, and no + // EMIT_TRAILING_ZERO_AFTER_POINT: + // ToPrecision(123450.0, 6) -> "123450" + // ToPrecision(123450.0, 5) -> "123450" + // ToPrecision(123450.0, 4) -> "123500" + // ToPrecision(123450.0, 3) -> "123000" + // ToPrecision(123450.0, 2) -> "1.2e5" + // + // Returns true if the conversion succeeds. The conversion always succeeds + // except for the following cases: + // - the input value is special and no infinity_symbol or nan_symbol has + // been provided to the constructor, + // - precision < kMinPericisionDigits + // - precision > kMaxPrecisionDigits + // The last condition implies that the result will never contain more than + // kMaxPrecisionDigits + 7 characters (the sign, the decimal point, the + // exponent character, the exponent's sign, and at most 3 exponent digits). + MFBT_API bool ToPrecision(double value, + int precision, + bool* used_exponential_notation, + StringBuilder* result_builder) const; + + enum DtoaMode { + // Produce the shortest correct representation. + // For example the output of 0.299999999999999988897 is (the less accurate + // but correct) 0.3. + SHORTEST, + // Same as SHORTEST, but for single-precision floats. + SHORTEST_SINGLE, + // Produce a fixed number of digits after the decimal point. + // For instance fixed(0.1, 4) becomes 0.1000 + // If the input number is big, the output will be big. + FIXED, + // Fixed number of digits (independent of the decimal point). + PRECISION + }; + + // The maximal number of digits that are needed to emit a double in base 10. + // A higher precision can be achieved by using more digits, but the shortest + // accurate representation of any double will never use more digits than + // kBase10MaximalLength. + // Note that DoubleToAscii null-terminates its input. So the given buffer + // should be at least kBase10MaximalLength + 1 characters long. + static const MFBT_DATA int kBase10MaximalLength = 17; + + // Converts the given double 'v' to ascii. 'v' must not be NaN, +Infinity, or + // -Infinity. In SHORTEST_SINGLE-mode this restriction also applies to 'v' + // after it has been casted to a single-precision float. That is, in this + // mode static_cast<float>(v) must not be NaN, +Infinity or -Infinity. + // + // The result should be interpreted as buffer * 10^(point-length). + // + // The output depends on the given mode: + // - SHORTEST: produce the least amount of digits for which the internal + // identity requirement is still satisfied. If the digits are printed + // (together with the correct exponent) then reading this number will give + // 'v' again. The buffer will choose the representation that is closest to + // 'v'. If there are two at the same distance, than the one farther away + // from 0 is chosen (halfway cases - ending with 5 - are rounded up). + // In this mode the 'requested_digits' parameter is ignored. + // - SHORTEST_SINGLE: same as SHORTEST but with single-precision. + // - FIXED: produces digits necessary to print a given number with + // 'requested_digits' digits after the decimal point. The produced digits + // might be too short in which case the caller has to fill the remainder + // with '0's. + // Example: toFixed(0.001, 5) is allowed to return buffer="1", point=-2. + // Halfway cases are rounded towards +/-Infinity (away from 0). The call + // toFixed(0.15, 2) thus returns buffer="2", point=0. + // The returned buffer may contain digits that would be truncated from the + // shortest representation of the input. + // - PRECISION: produces 'requested_digits' where the first digit is not '0'. + // Even though the length of produced digits usually equals + // 'requested_digits', the function is allowed to return fewer digits, in + // which case the caller has to fill the missing digits with '0's. + // Halfway cases are again rounded away from 0. + // DoubleToAscii expects the given buffer to be big enough to hold all + // digits and a terminating null-character. In SHORTEST-mode it expects a + // buffer of at least kBase10MaximalLength + 1. In all other modes the + // requested_digits parameter and the padding-zeroes limit the size of the + // output. Don't forget the decimal point, the exponent character and the + // terminating null-character when computing the maximal output size. + // The given length is only used in debug mode to ensure the buffer is big + // enough. + static MFBT_API void DoubleToAscii(double v, + DtoaMode mode, + int requested_digits, + char* buffer, + int buffer_length, + bool* sign, + int* length, + int* point); + + private: + // Implementation for ToShortest and ToShortestSingle. + MFBT_API bool ToShortestIeeeNumber(double value, + StringBuilder* result_builder, + DtoaMode mode) const; + + // If the value is a special value (NaN or Infinity) constructs the + // corresponding string using the configured infinity/nan-symbol. + // If either of them is NULL or the value is not special then the + // function returns false. + MFBT_API bool HandleSpecialValues(double value, StringBuilder* result_builder) const; + // Constructs an exponential representation (i.e. 1.234e56). + // The given exponent assumes a decimal point after the first decimal digit. + MFBT_API void CreateExponentialRepresentation(const char* decimal_digits, + int length, + int exponent, + StringBuilder* result_builder) const; + // Creates a decimal representation (i.e 1234.5678). + MFBT_API void CreateDecimalRepresentation(const char* decimal_digits, + int length, + int decimal_point, + int digits_after_point, + StringBuilder* result_builder) const; + + const int flags_; + const char* const infinity_symbol_; + const char* const nan_symbol_; + const char exponent_character_; + const int decimal_in_shortest_low_; + const int decimal_in_shortest_high_; + const int max_leading_padding_zeroes_in_precision_mode_; + const int max_trailing_padding_zeroes_in_precision_mode_; + + DISALLOW_IMPLICIT_CONSTRUCTORS(DoubleToStringConverter); +}; + + +class StringToDoubleConverter { + public: + // Enumeration for allowing octals and ignoring junk when converting + // strings to numbers. + enum Flags { + NO_FLAGS = 0, + ALLOW_HEX = 1, + ALLOW_OCTALS = 2, + ALLOW_TRAILING_JUNK = 4, + ALLOW_LEADING_SPACES = 8, + ALLOW_TRAILING_SPACES = 16, + ALLOW_SPACES_AFTER_SIGN = 32 + }; + + // Flags should be a bit-or combination of the possible Flags-enum. + // - NO_FLAGS: no special flags. + // - ALLOW_HEX: recognizes the prefix "0x". Hex numbers may only be integers. + // Ex: StringToDouble("0x1234") -> 4660.0 + // In StringToDouble("0x1234.56") the characters ".56" are trailing + // junk. The result of the call is hence dependent on + // the ALLOW_TRAILING_JUNK flag and/or the junk value. + // With this flag "0x" is a junk-string. Even with ALLOW_TRAILING_JUNK, + // the string will not be parsed as "0" followed by junk. + // + // - ALLOW_OCTALS: recognizes the prefix "0" for octals: + // If a sequence of octal digits starts with '0', then the number is + // read as octal integer. Octal numbers may only be integers. + // Ex: StringToDouble("01234") -> 668.0 + // StringToDouble("012349") -> 12349.0 // Not a sequence of octal + // // digits. + // In StringToDouble("01234.56") the characters ".56" are trailing + // junk. The result of the call is hence dependent on + // the ALLOW_TRAILING_JUNK flag and/or the junk value. + // In StringToDouble("01234e56") the characters "e56" are trailing + // junk, too. + // - ALLOW_TRAILING_JUNK: ignore trailing characters that are not part of + // a double literal. + // - ALLOW_LEADING_SPACES: skip over leading spaces. + // - ALLOW_TRAILING_SPACES: ignore trailing spaces. + // - ALLOW_SPACES_AFTER_SIGN: ignore spaces after the sign. + // Ex: StringToDouble("- 123.2") -> -123.2. + // StringToDouble("+ 123.2") -> 123.2 + // + // empty_string_value is returned when an empty string is given as input. + // If ALLOW_LEADING_SPACES or ALLOW_TRAILING_SPACES are set, then a string + // containing only spaces is converted to the 'empty_string_value', too. + // + // junk_string_value is returned when + // a) ALLOW_TRAILING_JUNK is not set, and a junk character (a character not + // part of a double-literal) is found. + // b) ALLOW_TRAILING_JUNK is set, but the string does not start with a + // double literal. + // + // infinity_symbol and nan_symbol are strings that are used to detect + // inputs that represent infinity and NaN. They can be null, in which case + // they are ignored. + // The conversion routine first reads any possible signs. Then it compares the + // following character of the input-string with the first character of + // the infinity, and nan-symbol. If either matches, the function assumes, that + // a match has been found, and expects the following input characters to match + // the remaining characters of the special-value symbol. + // This means that the following restrictions apply to special-value symbols: + // - they must not start with signs ('+', or '-'), + // - they must not have the same first character. + // - they must not start with digits. + // + // Examples: + // flags = ALLOW_HEX | ALLOW_TRAILING_JUNK, + // empty_string_value = 0.0, + // junk_string_value = NaN, + // infinity_symbol = "infinity", + // nan_symbol = "nan": + // StringToDouble("0x1234") -> 4660.0. + // StringToDouble("0x1234K") -> 4660.0. + // StringToDouble("") -> 0.0 // empty_string_value. + // StringToDouble(" ") -> NaN // junk_string_value. + // StringToDouble(" 1") -> NaN // junk_string_value. + // StringToDouble("0x") -> NaN // junk_string_value. + // StringToDouble("-123.45") -> -123.45. + // StringToDouble("--123.45") -> NaN // junk_string_value. + // StringToDouble("123e45") -> 123e45. + // StringToDouble("123E45") -> 123e45. + // StringToDouble("123e+45") -> 123e45. + // StringToDouble("123E-45") -> 123e-45. + // StringToDouble("123e") -> 123.0 // trailing junk ignored. + // StringToDouble("123e-") -> 123.0 // trailing junk ignored. + // StringToDouble("+NaN") -> NaN // NaN string literal. + // StringToDouble("-infinity") -> -inf. // infinity literal. + // StringToDouble("Infinity") -> NaN // junk_string_value. + // + // flags = ALLOW_OCTAL | ALLOW_LEADING_SPACES, + // empty_string_value = 0.0, + // junk_string_value = NaN, + // infinity_symbol = NULL, + // nan_symbol = NULL: + // StringToDouble("0x1234") -> NaN // junk_string_value. + // StringToDouble("01234") -> 668.0. + // StringToDouble("") -> 0.0 // empty_string_value. + // StringToDouble(" ") -> 0.0 // empty_string_value. + // StringToDouble(" 1") -> 1.0 + // StringToDouble("0x") -> NaN // junk_string_value. + // StringToDouble("0123e45") -> NaN // junk_string_value. + // StringToDouble("01239E45") -> 1239e45. + // StringToDouble("-infinity") -> NaN // junk_string_value. + // StringToDouble("NaN") -> NaN // junk_string_value. + StringToDoubleConverter(int flags, + double empty_string_value, + double junk_string_value, + const char* infinity_symbol, + const char* nan_symbol) + : flags_(flags), + empty_string_value_(empty_string_value), + junk_string_value_(junk_string_value), + infinity_symbol_(infinity_symbol), + nan_symbol_(nan_symbol) { + } + + // Performs the conversion. + // The output parameter 'processed_characters_count' is set to the number + // of characters that have been processed to read the number. + // Spaces than are processed with ALLOW_{LEADING|TRAILING}_SPACES are included + // in the 'processed_characters_count'. Trailing junk is never included. + double StringToDouble(const char* buffer, + int length, + int* processed_characters_count) const { + return StringToIeee(buffer, length, processed_characters_count, true); + } + + // Same as StringToDouble but reads a float. + // Note that this is not equivalent to static_cast<float>(StringToDouble(...)) + // due to potential double-rounding. + float StringToFloat(const char* buffer, + int length, + int* processed_characters_count) const { + return static_cast<float>(StringToIeee(buffer, length, + processed_characters_count, false)); + } + + private: + const int flags_; + const double empty_string_value_; + const double junk_string_value_; + const char* const infinity_symbol_; + const char* const nan_symbol_; + + double StringToIeee(const char* buffer, + int length, + int* processed_characters_count, + bool read_as_double) const; + + DISALLOW_IMPLICIT_CONSTRUCTORS(StringToDoubleConverter); +}; + +} // namespace double_conversion + +#endif // DOUBLE_CONVERSION_DOUBLE_CONVERSION_H_ diff --git a/mfbt/double-conversion/fast-dtoa.cc b/mfbt/double-conversion/fast-dtoa.cc new file mode 100644 index 000000000..1a0f82350 --- /dev/null +++ b/mfbt/double-conversion/fast-dtoa.cc @@ -0,0 +1,664 @@ +// Copyright 2012 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#include "fast-dtoa.h" + +#include "cached-powers.h" +#include "diy-fp.h" +#include "ieee.h" + +namespace double_conversion { + +// The minimal and maximal target exponent define the range of w's binary +// exponent, where 'w' is the result of multiplying the input by a cached power +// of ten. +// +// A different range might be chosen on a different platform, to optimize digit +// generation, but a smaller range requires more powers of ten to be cached. +static const int kMinimalTargetExponent = -60; +static const int kMaximalTargetExponent = -32; + + +// Adjusts the last digit of the generated number, and screens out generated +// solutions that may be inaccurate. A solution may be inaccurate if it is +// outside the safe interval, or if we cannot prove that it is closer to the +// input than a neighboring representation of the same length. +// +// Input: * buffer containing the digits of too_high / 10^kappa +// * the buffer's length +// * distance_too_high_w == (too_high - w).f() * unit +// * unsafe_interval == (too_high - too_low).f() * unit +// * rest = (too_high - buffer * 10^kappa).f() * unit +// * ten_kappa = 10^kappa * unit +// * unit = the common multiplier +// Output: returns true if the buffer is guaranteed to contain the closest +// representable number to the input. +// Modifies the generated digits in the buffer to approach (round towards) w. +static bool RoundWeed(Vector<char> buffer, + int length, + uint64_t distance_too_high_w, + uint64_t unsafe_interval, + uint64_t rest, + uint64_t ten_kappa, + uint64_t unit) { + uint64_t small_distance = distance_too_high_w - unit; + uint64_t big_distance = distance_too_high_w + unit; + // Let w_low = too_high - big_distance, and + // w_high = too_high - small_distance. + // Note: w_low < w < w_high + // + // The real w (* unit) must lie somewhere inside the interval + // ]w_low; w_high[ (often written as "(w_low; w_high)") + + // Basically the buffer currently contains a number in the unsafe interval + // ]too_low; too_high[ with too_low < w < too_high + // + // too_high - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + // ^v 1 unit ^ ^ ^ ^ + // boundary_high --------------------- . . . . + // ^v 1 unit . . . . + // - - - - - - - - - - - - - - - - - - - + - - + - - - - - - . . + // . . ^ . . + // . big_distance . . . + // . . . . rest + // small_distance . . . . + // v . . . . + // w_high - - - - - - - - - - - - - - - - - - . . . . + // ^v 1 unit . . . . + // w ---------------------------------------- . . . . + // ^v 1 unit v . . . + // w_low - - - - - - - - - - - - - - - - - - - - - . . . + // . . v + // buffer --------------------------------------------------+-------+-------- + // . . + // safe_interval . + // v . + // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - . + // ^v 1 unit . + // boundary_low ------------------------- unsafe_interval + // ^v 1 unit v + // too_low - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + // + // + // Note that the value of buffer could lie anywhere inside the range too_low + // to too_high. + // + // boundary_low, boundary_high and w are approximations of the real boundaries + // and v (the input number). They are guaranteed to be precise up to one unit. + // In fact the error is guaranteed to be strictly less than one unit. + // + // Anything that lies outside the unsafe interval is guaranteed not to round + // to v when read again. + // Anything that lies inside the safe interval is guaranteed to round to v + // when read again. + // If the number inside the buffer lies inside the unsafe interval but not + // inside the safe interval then we simply do not know and bail out (returning + // false). + // + // Similarly we have to take into account the imprecision of 'w' when finding + // the closest representation of 'w'. If we have two potential + // representations, and one is closer to both w_low and w_high, then we know + // it is closer to the actual value v. + // + // By generating the digits of too_high we got the largest (closest to + // too_high) buffer that is still in the unsafe interval. In the case where + // w_high < buffer < too_high we try to decrement the buffer. + // This way the buffer approaches (rounds towards) w. + // There are 3 conditions that stop the decrementation process: + // 1) the buffer is already below w_high + // 2) decrementing the buffer would make it leave the unsafe interval + // 3) decrementing the buffer would yield a number below w_high and farther + // away than the current number. In other words: + // (buffer{-1} < w_high) && w_high - buffer{-1} > buffer - w_high + // Instead of using the buffer directly we use its distance to too_high. + // Conceptually rest ~= too_high - buffer + // We need to do the following tests in this order to avoid over- and + // underflows. + ASSERT(rest <= unsafe_interval); + while (rest < small_distance && // Negated condition 1 + unsafe_interval - rest >= ten_kappa && // Negated condition 2 + (rest + ten_kappa < small_distance || // buffer{-1} > w_high + small_distance - rest >= rest + ten_kappa - small_distance)) { + buffer[length - 1]--; + rest += ten_kappa; + } + + // We have approached w+ as much as possible. We now test if approaching w- + // would require changing the buffer. If yes, then we have two possible + // representations close to w, but we cannot decide which one is closer. + if (rest < big_distance && + unsafe_interval - rest >= ten_kappa && + (rest + ten_kappa < big_distance || + big_distance - rest > rest + ten_kappa - big_distance)) { + return false; + } + + // Weeding test. + // The safe interval is [too_low + 2 ulp; too_high - 2 ulp] + // Since too_low = too_high - unsafe_interval this is equivalent to + // [too_high - unsafe_interval + 4 ulp; too_high - 2 ulp] + // Conceptually we have: rest ~= too_high - buffer + return (2 * unit <= rest) && (rest <= unsafe_interval - 4 * unit); +} + + +// Rounds the buffer upwards if the result is closer to v by possibly adding +// 1 to the buffer. If the precision of the calculation is not sufficient to +// round correctly, return false. +// The rounding might shift the whole buffer in which case the kappa is +// adjusted. For example "99", kappa = 3 might become "10", kappa = 4. +// +// If 2*rest > ten_kappa then the buffer needs to be round up. +// rest can have an error of +/- 1 unit. This function accounts for the +// imprecision and returns false, if the rounding direction cannot be +// unambiguously determined. +// +// Precondition: rest < ten_kappa. +static bool RoundWeedCounted(Vector<char> buffer, + int length, + uint64_t rest, + uint64_t ten_kappa, + uint64_t unit, + int* kappa) { + ASSERT(rest < ten_kappa); + // The following tests are done in a specific order to avoid overflows. They + // will work correctly with any uint64 values of rest < ten_kappa and unit. + // + // If the unit is too big, then we don't know which way to round. For example + // a unit of 50 means that the real number lies within rest +/- 50. If + // 10^kappa == 40 then there is no way to tell which way to round. + if (unit >= ten_kappa) return false; + // Even if unit is just half the size of 10^kappa we are already completely + // lost. (And after the previous test we know that the expression will not + // over/underflow.) + if (ten_kappa - unit <= unit) return false; + // If 2 * (rest + unit) <= 10^kappa we can safely round down. + if ((ten_kappa - rest > rest) && (ten_kappa - 2 * rest >= 2 * unit)) { + return true; + } + // If 2 * (rest - unit) >= 10^kappa, then we can safely round up. + if ((rest > unit) && (ten_kappa - (rest - unit) <= (rest - unit))) { + // Increment the last digit recursively until we find a non '9' digit. + buffer[length - 1]++; + for (int i = length - 1; i > 0; --i) { + if (buffer[i] != '0' + 10) break; + buffer[i] = '0'; + buffer[i - 1]++; + } + // If the first digit is now '0'+ 10 we had a buffer with all '9's. With the + // exception of the first digit all digits are now '0'. Simply switch the + // first digit to '1' and adjust the kappa. Example: "99" becomes "10" and + // the power (the kappa) is increased. + if (buffer[0] == '0' + 10) { + buffer[0] = '1'; + (*kappa) += 1; + } + return true; + } + return false; +} + +// Returns the biggest power of ten that is less than or equal to the given +// number. We furthermore receive the maximum number of bits 'number' has. +// +// Returns power == 10^(exponent_plus_one-1) such that +// power <= number < power * 10. +// If number_bits == 0 then 0^(0-1) is returned. +// The number of bits must be <= 32. +// Precondition: number < (1 << (number_bits + 1)). + +// Inspired by the method for finding an integer log base 10 from here: +// http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog10 +static unsigned int const kSmallPowersOfTen[] = + {0, 1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000, + 1000000000}; + +static void BiggestPowerTen(uint32_t number, + int number_bits, + uint32_t* power, + int* exponent_plus_one) { + ASSERT(number < (1u << (number_bits + 1))); + // 1233/4096 is approximately 1/lg(10). + int exponent_plus_one_guess = ((number_bits + 1) * 1233 >> 12); + // We increment to skip over the first entry in the kPowersOf10 table. + // Note: kPowersOf10[i] == 10^(i-1). + exponent_plus_one_guess++; + // We don't have any guarantees that 2^number_bits <= number. + // TODO(floitsch): can we change the 'while' into an 'if'? We definitely see + // number < (2^number_bits - 1), but I haven't encountered + // number < (2^number_bits - 2) yet. + while (number < kSmallPowersOfTen[exponent_plus_one_guess]) { + exponent_plus_one_guess--; + } + *power = kSmallPowersOfTen[exponent_plus_one_guess]; + *exponent_plus_one = exponent_plus_one_guess; +} + +// Generates the digits of input number w. +// w is a floating-point number (DiyFp), consisting of a significand and an +// exponent. Its exponent is bounded by kMinimalTargetExponent and +// kMaximalTargetExponent. +// Hence -60 <= w.e() <= -32. +// +// Returns false if it fails, in which case the generated digits in the buffer +// should not be used. +// Preconditions: +// * low, w and high are correct up to 1 ulp (unit in the last place). That +// is, their error must be less than a unit of their last digits. +// * low.e() == w.e() == high.e() +// * low < w < high, and taking into account their error: low~ <= high~ +// * kMinimalTargetExponent <= w.e() <= kMaximalTargetExponent +// Postconditions: returns false if procedure fails. +// otherwise: +// * buffer is not null-terminated, but len contains the number of digits. +// * buffer contains the shortest possible decimal digit-sequence +// such that LOW < buffer * 10^kappa < HIGH, where LOW and HIGH are the +// correct values of low and high (without their error). +// * if more than one decimal representation gives the minimal number of +// decimal digits then the one closest to W (where W is the correct value +// of w) is chosen. +// Remark: this procedure takes into account the imprecision of its input +// numbers. If the precision is not enough to guarantee all the postconditions +// then false is returned. This usually happens rarely (~0.5%). +// +// Say, for the sake of example, that +// w.e() == -48, and w.f() == 0x1234567890abcdef +// w's value can be computed by w.f() * 2^w.e() +// We can obtain w's integral digits by simply shifting w.f() by -w.e(). +// -> w's integral part is 0x1234 +// w's fractional part is therefore 0x567890abcdef. +// Printing w's integral part is easy (simply print 0x1234 in decimal). +// In order to print its fraction we repeatedly multiply the fraction by 10 and +// get each digit. Example the first digit after the point would be computed by +// (0x567890abcdef * 10) >> 48. -> 3 +// The whole thing becomes slightly more complicated because we want to stop +// once we have enough digits. That is, once the digits inside the buffer +// represent 'w' we can stop. Everything inside the interval low - high +// represents w. However we have to pay attention to low, high and w's +// imprecision. +static bool DigitGen(DiyFp low, + DiyFp w, + DiyFp high, + Vector<char> buffer, + int* length, + int* kappa) { + ASSERT(low.e() == w.e() && w.e() == high.e()); + ASSERT(low.f() + 1 <= high.f() - 1); + ASSERT(kMinimalTargetExponent <= w.e() && w.e() <= kMaximalTargetExponent); + // low, w and high are imprecise, but by less than one ulp (unit in the last + // place). + // If we remove (resp. add) 1 ulp from low (resp. high) we are certain that + // the new numbers are outside of the interval we want the final + // representation to lie in. + // Inversely adding (resp. removing) 1 ulp from low (resp. high) would yield + // numbers that are certain to lie in the interval. We will use this fact + // later on. + // We will now start by generating the digits within the uncertain + // interval. Later we will weed out representations that lie outside the safe + // interval and thus _might_ lie outside the correct interval. + uint64_t unit = 1; + DiyFp too_low = DiyFp(low.f() - unit, low.e()); + DiyFp too_high = DiyFp(high.f() + unit, high.e()); + // too_low and too_high are guaranteed to lie outside the interval we want the + // generated number in. + DiyFp unsafe_interval = DiyFp::Minus(too_high, too_low); + // We now cut the input number into two parts: the integral digits and the + // fractionals. We will not write any decimal separator though, but adapt + // kappa instead. + // Reminder: we are currently computing the digits (stored inside the buffer) + // such that: too_low < buffer * 10^kappa < too_high + // We use too_high for the digit_generation and stop as soon as possible. + // If we stop early we effectively round down. + DiyFp one = DiyFp(static_cast<uint64_t>(1) << -w.e(), w.e()); + // Division by one is a shift. + uint32_t integrals = static_cast<uint32_t>(too_high.f() >> -one.e()); + // Modulo by one is an and. + uint64_t fractionals = too_high.f() & (one.f() - 1); + uint32_t divisor; + int divisor_exponent_plus_one; + BiggestPowerTen(integrals, DiyFp::kSignificandSize - (-one.e()), + &divisor, &divisor_exponent_plus_one); + *kappa = divisor_exponent_plus_one; + *length = 0; + // Loop invariant: buffer = too_high / 10^kappa (integer division) + // The invariant holds for the first iteration: kappa has been initialized + // with the divisor exponent + 1. And the divisor is the biggest power of ten + // that is smaller than integrals. + while (*kappa > 0) { + int digit = integrals / divisor; + buffer[*length] = '0' + digit; + (*length)++; + integrals %= divisor; + (*kappa)--; + // Note that kappa now equals the exponent of the divisor and that the + // invariant thus holds again. + uint64_t rest = + (static_cast<uint64_t>(integrals) << -one.e()) + fractionals; + // Invariant: too_high = buffer * 10^kappa + DiyFp(rest, one.e()) + // Reminder: unsafe_interval.e() == one.e() + if (rest < unsafe_interval.f()) { + // Rounding down (by not emitting the remaining digits) yields a number + // that lies within the unsafe interval. + return RoundWeed(buffer, *length, DiyFp::Minus(too_high, w).f(), + unsafe_interval.f(), rest, + static_cast<uint64_t>(divisor) << -one.e(), unit); + } + divisor /= 10; + } + + // The integrals have been generated. We are at the point of the decimal + // separator. In the following loop we simply multiply the remaining digits by + // 10 and divide by one. We just need to pay attention to multiply associated + // data (like the interval or 'unit'), too. + // Note that the multiplication by 10 does not overflow, because w.e >= -60 + // and thus one.e >= -60. + ASSERT(one.e() >= -60); + ASSERT(fractionals < one.f()); + ASSERT(UINT64_2PART_C(0xFFFFFFFF, FFFFFFFF) / 10 >= one.f()); + while (true) { + fractionals *= 10; + unit *= 10; + unsafe_interval.set_f(unsafe_interval.f() * 10); + // Integer division by one. + int digit = static_cast<int>(fractionals >> -one.e()); + buffer[*length] = '0' + digit; + (*length)++; + fractionals &= one.f() - 1; // Modulo by one. + (*kappa)--; + if (fractionals < unsafe_interval.f()) { + return RoundWeed(buffer, *length, DiyFp::Minus(too_high, w).f() * unit, + unsafe_interval.f(), fractionals, one.f(), unit); + } + } +} + + + +// Generates (at most) requested_digits digits of input number w. +// w is a floating-point number (DiyFp), consisting of a significand and an +// exponent. Its exponent is bounded by kMinimalTargetExponent and +// kMaximalTargetExponent. +// Hence -60 <= w.e() <= -32. +// +// Returns false if it fails, in which case the generated digits in the buffer +// should not be used. +// Preconditions: +// * w is correct up to 1 ulp (unit in the last place). That +// is, its error must be strictly less than a unit of its last digit. +// * kMinimalTargetExponent <= w.e() <= kMaximalTargetExponent +// +// Postconditions: returns false if procedure fails. +// otherwise: +// * buffer is not null-terminated, but length contains the number of +// digits. +// * the representation in buffer is the most precise representation of +// requested_digits digits. +// * buffer contains at most requested_digits digits of w. If there are less +// than requested_digits digits then some trailing '0's have been removed. +// * kappa is such that +// w = buffer * 10^kappa + eps with |eps| < 10^kappa / 2. +// +// Remark: This procedure takes into account the imprecision of its input +// numbers. If the precision is not enough to guarantee all the postconditions +// then false is returned. This usually happens rarely, but the failure-rate +// increases with higher requested_digits. +static bool DigitGenCounted(DiyFp w, + int requested_digits, + Vector<char> buffer, + int* length, + int* kappa) { + ASSERT(kMinimalTargetExponent <= w.e() && w.e() <= kMaximalTargetExponent); + ASSERT(kMinimalTargetExponent >= -60); + ASSERT(kMaximalTargetExponent <= -32); + // w is assumed to have an error less than 1 unit. Whenever w is scaled we + // also scale its error. + uint64_t w_error = 1; + // We cut the input number into two parts: the integral digits and the + // fractional digits. We don't emit any decimal separator, but adapt kappa + // instead. Example: instead of writing "1.2" we put "12" into the buffer and + // increase kappa by 1. + DiyFp one = DiyFp(static_cast<uint64_t>(1) << -w.e(), w.e()); + // Division by one is a shift. + uint32_t integrals = static_cast<uint32_t>(w.f() >> -one.e()); + // Modulo by one is an and. + uint64_t fractionals = w.f() & (one.f() - 1); + uint32_t divisor; + int divisor_exponent_plus_one; + BiggestPowerTen(integrals, DiyFp::kSignificandSize - (-one.e()), + &divisor, &divisor_exponent_plus_one); + *kappa = divisor_exponent_plus_one; + *length = 0; + + // Loop invariant: buffer = w / 10^kappa (integer division) + // The invariant holds for the first iteration: kappa has been initialized + // with the divisor exponent + 1. And the divisor is the biggest power of ten + // that is smaller than 'integrals'. + while (*kappa > 0) { + int digit = integrals / divisor; + buffer[*length] = '0' + digit; + (*length)++; + requested_digits--; + integrals %= divisor; + (*kappa)--; + // Note that kappa now equals the exponent of the divisor and that the + // invariant thus holds again. + if (requested_digits == 0) break; + divisor /= 10; + } + + if (requested_digits == 0) { + uint64_t rest = + (static_cast<uint64_t>(integrals) << -one.e()) + fractionals; + return RoundWeedCounted(buffer, *length, rest, + static_cast<uint64_t>(divisor) << -one.e(), w_error, + kappa); + } + + // The integrals have been generated. We are at the point of the decimal + // separator. In the following loop we simply multiply the remaining digits by + // 10 and divide by one. We just need to pay attention to multiply associated + // data (the 'unit'), too. + // Note that the multiplication by 10 does not overflow, because w.e >= -60 + // and thus one.e >= -60. + ASSERT(one.e() >= -60); + ASSERT(fractionals < one.f()); + ASSERT(UINT64_2PART_C(0xFFFFFFFF, FFFFFFFF) / 10 >= one.f()); + while (requested_digits > 0 && fractionals > w_error) { + fractionals *= 10; + w_error *= 10; + // Integer division by one. + int digit = static_cast<int>(fractionals >> -one.e()); + buffer[*length] = '0' + digit; + (*length)++; + requested_digits--; + fractionals &= one.f() - 1; // Modulo by one. + (*kappa)--; + } + if (requested_digits != 0) return false; + return RoundWeedCounted(buffer, *length, fractionals, one.f(), w_error, + kappa); +} + + +// Provides a decimal representation of v. +// Returns true if it succeeds, otherwise the result cannot be trusted. +// There will be *length digits inside the buffer (not null-terminated). +// If the function returns true then +// v == (double) (buffer * 10^decimal_exponent). +// The digits in the buffer are the shortest representation possible: no +// 0.09999999999999999 instead of 0.1. The shorter representation will even be +// chosen even if the longer one would be closer to v. +// The last digit will be closest to the actual v. That is, even if several +// digits might correctly yield 'v' when read again, the closest will be +// computed. +static bool Grisu3(double v, + FastDtoaMode mode, + Vector<char> buffer, + int* length, + int* decimal_exponent) { + DiyFp w = Double(v).AsNormalizedDiyFp(); + // boundary_minus and boundary_plus are the boundaries between v and its + // closest floating-point neighbors. Any number strictly between + // boundary_minus and boundary_plus will round to v when convert to a double. + // Grisu3 will never output representations that lie exactly on a boundary. + DiyFp boundary_minus, boundary_plus; + if (mode == FAST_DTOA_SHORTEST) { + Double(v).NormalizedBoundaries(&boundary_minus, &boundary_plus); + } else { + ASSERT(mode == FAST_DTOA_SHORTEST_SINGLE); + float single_v = static_cast<float>(v); + Single(single_v).NormalizedBoundaries(&boundary_minus, &boundary_plus); + } + ASSERT(boundary_plus.e() == w.e()); + DiyFp ten_mk; // Cached power of ten: 10^-k + int mk; // -k + int ten_mk_minimal_binary_exponent = + kMinimalTargetExponent - (w.e() + DiyFp::kSignificandSize); + int ten_mk_maximal_binary_exponent = + kMaximalTargetExponent - (w.e() + DiyFp::kSignificandSize); + PowersOfTenCache::GetCachedPowerForBinaryExponentRange( + ten_mk_minimal_binary_exponent, + ten_mk_maximal_binary_exponent, + &ten_mk, &mk); + ASSERT((kMinimalTargetExponent <= w.e() + ten_mk.e() + + DiyFp::kSignificandSize) && + (kMaximalTargetExponent >= w.e() + ten_mk.e() + + DiyFp::kSignificandSize)); + // Note that ten_mk is only an approximation of 10^-k. A DiyFp only contains a + // 64 bit significand and ten_mk is thus only precise up to 64 bits. + + // The DiyFp::Times procedure rounds its result, and ten_mk is approximated + // too. The variable scaled_w (as well as scaled_boundary_minus/plus) are now + // off by a small amount. + // In fact: scaled_w - w*10^k < 1ulp (unit in the last place) of scaled_w. + // In other words: let f = scaled_w.f() and e = scaled_w.e(), then + // (f-1) * 2^e < w*10^k < (f+1) * 2^e + DiyFp scaled_w = DiyFp::Times(w, ten_mk); + ASSERT(scaled_w.e() == + boundary_plus.e() + ten_mk.e() + DiyFp::kSignificandSize); + // In theory it would be possible to avoid some recomputations by computing + // the difference between w and boundary_minus/plus (a power of 2) and to + // compute scaled_boundary_minus/plus by subtracting/adding from + // scaled_w. However the code becomes much less readable and the speed + // enhancements are not terriffic. + DiyFp scaled_boundary_minus = DiyFp::Times(boundary_minus, ten_mk); + DiyFp scaled_boundary_plus = DiyFp::Times(boundary_plus, ten_mk); + + // DigitGen will generate the digits of scaled_w. Therefore we have + // v == (double) (scaled_w * 10^-mk). + // Set decimal_exponent == -mk and pass it to DigitGen. If scaled_w is not an + // integer than it will be updated. For instance if scaled_w == 1.23 then + // the buffer will be filled with "123" und the decimal_exponent will be + // decreased by 2. + int kappa; + bool result = DigitGen(scaled_boundary_minus, scaled_w, scaled_boundary_plus, + buffer, length, &kappa); + *decimal_exponent = -mk + kappa; + return result; +} + + +// The "counted" version of grisu3 (see above) only generates requested_digits +// number of digits. This version does not generate the shortest representation, +// and with enough requested digits 0.1 will at some point print as 0.9999999... +// Grisu3 is too imprecise for real halfway cases (1.5 will not work) and +// therefore the rounding strategy for halfway cases is irrelevant. +static bool Grisu3Counted(double v, + int requested_digits, + Vector<char> buffer, + int* length, + int* decimal_exponent) { + DiyFp w = Double(v).AsNormalizedDiyFp(); + DiyFp ten_mk; // Cached power of ten: 10^-k + int mk; // -k + int ten_mk_minimal_binary_exponent = + kMinimalTargetExponent - (w.e() + DiyFp::kSignificandSize); + int ten_mk_maximal_binary_exponent = + kMaximalTargetExponent - (w.e() + DiyFp::kSignificandSize); + PowersOfTenCache::GetCachedPowerForBinaryExponentRange( + ten_mk_minimal_binary_exponent, + ten_mk_maximal_binary_exponent, + &ten_mk, &mk); + ASSERT((kMinimalTargetExponent <= w.e() + ten_mk.e() + + DiyFp::kSignificandSize) && + (kMaximalTargetExponent >= w.e() + ten_mk.e() + + DiyFp::kSignificandSize)); + // Note that ten_mk is only an approximation of 10^-k. A DiyFp only contains a + // 64 bit significand and ten_mk is thus only precise up to 64 bits. + + // The DiyFp::Times procedure rounds its result, and ten_mk is approximated + // too. The variable scaled_w (as well as scaled_boundary_minus/plus) are now + // off by a small amount. + // In fact: scaled_w - w*10^k < 1ulp (unit in the last place) of scaled_w. + // In other words: let f = scaled_w.f() and e = scaled_w.e(), then + // (f-1) * 2^e < w*10^k < (f+1) * 2^e + DiyFp scaled_w = DiyFp::Times(w, ten_mk); + + // We now have (double) (scaled_w * 10^-mk). + // DigitGen will generate the first requested_digits digits of scaled_w and + // return together with a kappa such that scaled_w ~= buffer * 10^kappa. (It + // will not always be exactly the same since DigitGenCounted only produces a + // limited number of digits.) + int kappa; + bool result = DigitGenCounted(scaled_w, requested_digits, + buffer, length, &kappa); + *decimal_exponent = -mk + kappa; + return result; +} + + +bool FastDtoa(double v, + FastDtoaMode mode, + int requested_digits, + Vector<char> buffer, + int* length, + int* decimal_point) { + ASSERT(v > 0); + ASSERT(!Double(v).IsSpecial()); + + bool result = false; + int decimal_exponent = 0; + switch (mode) { + case FAST_DTOA_SHORTEST: + case FAST_DTOA_SHORTEST_SINGLE: + result = Grisu3(v, mode, buffer, length, &decimal_exponent); + break; + case FAST_DTOA_PRECISION: + result = Grisu3Counted(v, requested_digits, + buffer, length, &decimal_exponent); + break; + default: + UNREACHABLE(); + } + if (result) { + *decimal_point = *length + decimal_exponent; + buffer[*length] = '\0'; + } + return result; +} + +} // namespace double_conversion diff --git a/mfbt/double-conversion/fast-dtoa.h b/mfbt/double-conversion/fast-dtoa.h new file mode 100644 index 000000000..5f1e8eee5 --- /dev/null +++ b/mfbt/double-conversion/fast-dtoa.h @@ -0,0 +1,88 @@ +// Copyright 2010 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#ifndef DOUBLE_CONVERSION_FAST_DTOA_H_ +#define DOUBLE_CONVERSION_FAST_DTOA_H_ + +#include "utils.h" + +namespace double_conversion { + +enum FastDtoaMode { + // Computes the shortest representation of the given input. The returned + // result will be the most accurate number of this length. Longer + // representations might be more accurate. + FAST_DTOA_SHORTEST, + // Same as FAST_DTOA_SHORTEST but for single-precision floats. + FAST_DTOA_SHORTEST_SINGLE, + // Computes a representation where the precision (number of digits) is + // given as input. The precision is independent of the decimal point. + FAST_DTOA_PRECISION +}; + +// FastDtoa will produce at most kFastDtoaMaximalLength digits. This does not +// include the terminating '\0' character. +static const int kFastDtoaMaximalLength = 17; +// Same for single-precision numbers. +static const int kFastDtoaMaximalSingleLength = 9; + +// Provides a decimal representation of v. +// The result should be interpreted as buffer * 10^(point - length). +// +// Precondition: +// * v must be a strictly positive finite double. +// +// Returns true if it succeeds, otherwise the result can not be trusted. +// There will be *length digits inside the buffer followed by a null terminator. +// If the function returns true and mode equals +// - FAST_DTOA_SHORTEST, then +// the parameter requested_digits is ignored. +// The result satisfies +// v == (double) (buffer * 10^(point - length)). +// The digits in the buffer are the shortest representation possible. E.g. +// if 0.099999999999 and 0.1 represent the same double then "1" is returned +// with point = 0. +// The last digit will be closest to the actual v. That is, even if several +// digits might correctly yield 'v' when read again, the buffer will contain +// the one closest to v. +// - FAST_DTOA_PRECISION, then +// the buffer contains requested_digits digits. +// the difference v - (buffer * 10^(point-length)) is closest to zero for +// all possible representations of requested_digits digits. +// If there are two values that are equally close, then FastDtoa returns +// false. +// For both modes the buffer must be large enough to hold the result. +bool FastDtoa(double d, + FastDtoaMode mode, + int requested_digits, + Vector<char> buffer, + int* length, + int* decimal_point); + +} // namespace double_conversion + +#endif // DOUBLE_CONVERSION_FAST_DTOA_H_ diff --git a/mfbt/double-conversion/fixed-dtoa.cc b/mfbt/double-conversion/fixed-dtoa.cc new file mode 100644 index 000000000..d56b1449b --- /dev/null +++ b/mfbt/double-conversion/fixed-dtoa.cc @@ -0,0 +1,402 @@ +// Copyright 2010 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#include <math.h> + +#include "fixed-dtoa.h" +#include "ieee.h" + +namespace double_conversion { + +// Represents a 128bit type. This class should be replaced by a native type on +// platforms that support 128bit integers. +class UInt128 { + public: + UInt128() : high_bits_(0), low_bits_(0) { } + UInt128(uint64_t high, uint64_t low) : high_bits_(high), low_bits_(low) { } + + void Multiply(uint32_t multiplicand) { + uint64_t accumulator; + + accumulator = (low_bits_ & kMask32) * multiplicand; + uint32_t part = static_cast<uint32_t>(accumulator & kMask32); + accumulator >>= 32; + accumulator = accumulator + (low_bits_ >> 32) * multiplicand; + low_bits_ = (accumulator << 32) + part; + accumulator >>= 32; + accumulator = accumulator + (high_bits_ & kMask32) * multiplicand; + part = static_cast<uint32_t>(accumulator & kMask32); + accumulator >>= 32; + accumulator = accumulator + (high_bits_ >> 32) * multiplicand; + high_bits_ = (accumulator << 32) + part; + ASSERT((accumulator >> 32) == 0); + } + + void Shift(int shift_amount) { + ASSERT(-64 <= shift_amount && shift_amount <= 64); + if (shift_amount == 0) { + return; + } else if (shift_amount == -64) { + high_bits_ = low_bits_; + low_bits_ = 0; + } else if (shift_amount == 64) { + low_bits_ = high_bits_; + high_bits_ = 0; + } else if (shift_amount <= 0) { + high_bits_ <<= -shift_amount; + high_bits_ += low_bits_ >> (64 + shift_amount); + low_bits_ <<= -shift_amount; + } else { + low_bits_ >>= shift_amount; + low_bits_ += high_bits_ << (64 - shift_amount); + high_bits_ >>= shift_amount; + } + } + + // Modifies *this to *this MOD (2^power). + // Returns *this DIV (2^power). + int DivModPowerOf2(int power) { + if (power >= 64) { + int result = static_cast<int>(high_bits_ >> (power - 64)); + high_bits_ -= static_cast<uint64_t>(result) << (power - 64); + return result; + } else { + uint64_t part_low = low_bits_ >> power; + uint64_t part_high = high_bits_ << (64 - power); + int result = static_cast<int>(part_low + part_high); + high_bits_ = 0; + low_bits_ -= part_low << power; + return result; + } + } + + bool IsZero() const { + return high_bits_ == 0 && low_bits_ == 0; + } + + int BitAt(int position) { + if (position >= 64) { + return static_cast<int>(high_bits_ >> (position - 64)) & 1; + } else { + return static_cast<int>(low_bits_ >> position) & 1; + } + } + + private: + static const uint64_t kMask32 = 0xFFFFFFFF; + // Value == (high_bits_ << 64) + low_bits_ + uint64_t high_bits_; + uint64_t low_bits_; +}; + + +static const int kDoubleSignificandSize = 53; // Includes the hidden bit. + + +static void FillDigits32FixedLength(uint32_t number, int requested_length, + Vector<char> buffer, int* length) { + for (int i = requested_length - 1; i >= 0; --i) { + buffer[(*length) + i] = '0' + number % 10; + number /= 10; + } + *length += requested_length; +} + + +static void FillDigits32(uint32_t number, Vector<char> buffer, int* length) { + int number_length = 0; + // We fill the digits in reverse order and exchange them afterwards. + while (number != 0) { + int digit = number % 10; + number /= 10; + buffer[(*length) + number_length] = '0' + digit; + number_length++; + } + // Exchange the digits. + int i = *length; + int j = *length + number_length - 1; + while (i < j) { + char tmp = buffer[i]; + buffer[i] = buffer[j]; + buffer[j] = tmp; + i++; + j--; + } + *length += number_length; +} + + +static void FillDigits64FixedLength(uint64_t number, int requested_length, + Vector<char> buffer, int* length) { + const uint32_t kTen7 = 10000000; + // For efficiency cut the number into 3 uint32_t parts, and print those. + uint32_t part2 = static_cast<uint32_t>(number % kTen7); + number /= kTen7; + uint32_t part1 = static_cast<uint32_t>(number % kTen7); + uint32_t part0 = static_cast<uint32_t>(number / kTen7); + + FillDigits32FixedLength(part0, 3, buffer, length); + FillDigits32FixedLength(part1, 7, buffer, length); + FillDigits32FixedLength(part2, 7, buffer, length); +} + + +static void FillDigits64(uint64_t number, Vector<char> buffer, int* length) { + const uint32_t kTen7 = 10000000; + // For efficiency cut the number into 3 uint32_t parts, and print those. + uint32_t part2 = static_cast<uint32_t>(number % kTen7); + number /= kTen7; + uint32_t part1 = static_cast<uint32_t>(number % kTen7); + uint32_t part0 = static_cast<uint32_t>(number / kTen7); + + if (part0 != 0) { + FillDigits32(part0, buffer, length); + FillDigits32FixedLength(part1, 7, buffer, length); + FillDigits32FixedLength(part2, 7, buffer, length); + } else if (part1 != 0) { + FillDigits32(part1, buffer, length); + FillDigits32FixedLength(part2, 7, buffer, length); + } else { + FillDigits32(part2, buffer, length); + } +} + + +static void RoundUp(Vector<char> buffer, int* length, int* decimal_point) { + // An empty buffer represents 0. + if (*length == 0) { + buffer[0] = '1'; + *decimal_point = 1; + *length = 1; + return; + } + // Round the last digit until we either have a digit that was not '9' or until + // we reached the first digit. + buffer[(*length) - 1]++; + for (int i = (*length) - 1; i > 0; --i) { + if (buffer[i] != '0' + 10) { + return; + } + buffer[i] = '0'; + buffer[i - 1]++; + } + // If the first digit is now '0' + 10, we would need to set it to '0' and add + // a '1' in front. However we reach the first digit only if all following + // digits had been '9' before rounding up. Now all trailing digits are '0' and + // we simply switch the first digit to '1' and update the decimal-point + // (indicating that the point is now one digit to the right). + if (buffer[0] == '0' + 10) { + buffer[0] = '1'; + (*decimal_point)++; + } +} + + +// The given fractionals number represents a fixed-point number with binary +// point at bit (-exponent). +// Preconditions: +// -128 <= exponent <= 0. +// 0 <= fractionals * 2^exponent < 1 +// The buffer holds the result. +// The function will round its result. During the rounding-process digits not +// generated by this function might be updated, and the decimal-point variable +// might be updated. If this function generates the digits 99 and the buffer +// already contained "199" (thus yielding a buffer of "19999") then a +// rounding-up will change the contents of the buffer to "20000". +static void FillFractionals(uint64_t fractionals, int exponent, + int fractional_count, Vector<char> buffer, + int* length, int* decimal_point) { + ASSERT(-128 <= exponent && exponent <= 0); + // 'fractionals' is a fixed-point number, with binary point at bit + // (-exponent). Inside the function the non-converted remainder of fractionals + // is a fixed-point number, with binary point at bit 'point'. + if (-exponent <= 64) { + // One 64 bit number is sufficient. + ASSERT(fractionals >> 56 == 0); + int point = -exponent; + for (int i = 0; i < fractional_count; ++i) { + if (fractionals == 0) break; + // Instead of multiplying by 10 we multiply by 5 and adjust the point + // location. This way the fractionals variable will not overflow. + // Invariant at the beginning of the loop: fractionals < 2^point. + // Initially we have: point <= 64 and fractionals < 2^56 + // After each iteration the point is decremented by one. + // Note that 5^3 = 125 < 128 = 2^7. + // Therefore three iterations of this loop will not overflow fractionals + // (even without the subtraction at the end of the loop body). At this + // time point will satisfy point <= 61 and therefore fractionals < 2^point + // and any further multiplication of fractionals by 5 will not overflow. + fractionals *= 5; + point--; + int digit = static_cast<int>(fractionals >> point); + buffer[*length] = '0' + digit; + (*length)++; + fractionals -= static_cast<uint64_t>(digit) << point; + } + // If the first bit after the point is set we have to round up. + if (((fractionals >> (point - 1)) & 1) == 1) { + RoundUp(buffer, length, decimal_point); + } + } else { // We need 128 bits. + ASSERT(64 < -exponent && -exponent <= 128); + UInt128 fractionals128 = UInt128(fractionals, 0); + fractionals128.Shift(-exponent - 64); + int point = 128; + for (int i = 0; i < fractional_count; ++i) { + if (fractionals128.IsZero()) break; + // As before: instead of multiplying by 10 we multiply by 5 and adjust the + // point location. + // This multiplication will not overflow for the same reasons as before. + fractionals128.Multiply(5); + point--; + int digit = fractionals128.DivModPowerOf2(point); + buffer[*length] = '0' + digit; + (*length)++; + } + if (fractionals128.BitAt(point - 1) == 1) { + RoundUp(buffer, length, decimal_point); + } + } +} + + +// Removes leading and trailing zeros. +// If leading zeros are removed then the decimal point position is adjusted. +static void TrimZeros(Vector<char> buffer, int* length, int* decimal_point) { + while (*length > 0 && buffer[(*length) - 1] == '0') { + (*length)--; + } + int first_non_zero = 0; + while (first_non_zero < *length && buffer[first_non_zero] == '0') { + first_non_zero++; + } + if (first_non_zero != 0) { + for (int i = first_non_zero; i < *length; ++i) { + buffer[i - first_non_zero] = buffer[i]; + } + *length -= first_non_zero; + *decimal_point -= first_non_zero; + } +} + + +bool FastFixedDtoa(double v, + int fractional_count, + Vector<char> buffer, + int* length, + int* decimal_point) { + const uint32_t kMaxUInt32 = 0xFFFFFFFF; + uint64_t significand = Double(v).Significand(); + int exponent = Double(v).Exponent(); + // v = significand * 2^exponent (with significand a 53bit integer). + // If the exponent is larger than 20 (i.e. we may have a 73bit number) then we + // don't know how to compute the representation. 2^73 ~= 9.5*10^21. + // If necessary this limit could probably be increased, but we don't need + // more. + if (exponent > 20) return false; + if (fractional_count > 20) return false; + *length = 0; + // At most kDoubleSignificandSize bits of the significand are non-zero. + // Given a 64 bit integer we have 11 0s followed by 53 potentially non-zero + // bits: 0..11*..0xxx..53*..xx + if (exponent + kDoubleSignificandSize > 64) { + // The exponent must be > 11. + // + // We know that v = significand * 2^exponent. + // And the exponent > 11. + // We simplify the task by dividing v by 10^17. + // The quotient delivers the first digits, and the remainder fits into a 64 + // bit number. + // Dividing by 10^17 is equivalent to dividing by 5^17*2^17. + const uint64_t kFive17 = UINT64_2PART_C(0xB1, A2BC2EC5); // 5^17 + uint64_t divisor = kFive17; + int divisor_power = 17; + uint64_t dividend = significand; + uint32_t quotient; + uint64_t remainder; + // Let v = f * 2^e with f == significand and e == exponent. + // Then need q (quotient) and r (remainder) as follows: + // v = q * 10^17 + r + // f * 2^e = q * 10^17 + r + // f * 2^e = q * 5^17 * 2^17 + r + // If e > 17 then + // f * 2^(e-17) = q * 5^17 + r/2^17 + // else + // f = q * 5^17 * 2^(17-e) + r/2^e + if (exponent > divisor_power) { + // We only allow exponents of up to 20 and therefore (17 - e) <= 3 + dividend <<= exponent - divisor_power; + quotient = static_cast<uint32_t>(dividend / divisor); + remainder = (dividend % divisor) << divisor_power; + } else { + divisor <<= divisor_power - exponent; + quotient = static_cast<uint32_t>(dividend / divisor); + remainder = (dividend % divisor) << exponent; + } + FillDigits32(quotient, buffer, length); + FillDigits64FixedLength(remainder, divisor_power, buffer, length); + *decimal_point = *length; + } else if (exponent >= 0) { + // 0 <= exponent <= 11 + significand <<= exponent; + FillDigits64(significand, buffer, length); + *decimal_point = *length; + } else if (exponent > -kDoubleSignificandSize) { + // We have to cut the number. + uint64_t integrals = significand >> -exponent; + uint64_t fractionals = significand - (integrals << -exponent); + if (integrals > kMaxUInt32) { + FillDigits64(integrals, buffer, length); + } else { + FillDigits32(static_cast<uint32_t>(integrals), buffer, length); + } + *decimal_point = *length; + FillFractionals(fractionals, exponent, fractional_count, + buffer, length, decimal_point); + } else if (exponent < -128) { + // This configuration (with at most 20 digits) means that all digits must be + // 0. + ASSERT(fractional_count <= 20); + buffer[0] = '\0'; + *length = 0; + *decimal_point = -fractional_count; + } else { + *decimal_point = 0; + FillFractionals(significand, exponent, fractional_count, + buffer, length, decimal_point); + } + TrimZeros(buffer, length, decimal_point); + buffer[*length] = '\0'; + if ((*length) == 0) { + // The string is empty and the decimal_point thus has no importance. Mimick + // Gay's dtoa and and set it to -fractional_count. + *decimal_point = -fractional_count; + } + return true; +} + +} // namespace double_conversion diff --git a/mfbt/double-conversion/fixed-dtoa.h b/mfbt/double-conversion/fixed-dtoa.h new file mode 100644 index 000000000..3bdd08e21 --- /dev/null +++ b/mfbt/double-conversion/fixed-dtoa.h @@ -0,0 +1,56 @@ +// Copyright 2010 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#ifndef DOUBLE_CONVERSION_FIXED_DTOA_H_ +#define DOUBLE_CONVERSION_FIXED_DTOA_H_ + +#include "utils.h" + +namespace double_conversion { + +// Produces digits necessary to print a given number with +// 'fractional_count' digits after the decimal point. +// The buffer must be big enough to hold the result plus one terminating null +// character. +// +// The produced digits might be too short in which case the caller has to fill +// the gaps with '0's. +// Example: FastFixedDtoa(0.001, 5, ...) is allowed to return buffer = "1", and +// decimal_point = -2. +// Halfway cases are rounded towards +/-Infinity (away from 0). The call +// FastFixedDtoa(0.15, 2, ...) thus returns buffer = "2", decimal_point = 0. +// The returned buffer may contain digits that would be truncated from the +// shortest representation of the input. +// +// This method only works for some parameters. If it can't handle the input it +// returns false. The output is null-terminated when the function succeeds. +bool FastFixedDtoa(double v, int fractional_count, + Vector<char> buffer, int* length, int* decimal_point); + +} // namespace double_conversion + +#endif // DOUBLE_CONVERSION_FIXED_DTOA_H_ diff --git a/mfbt/double-conversion/ieee.h b/mfbt/double-conversion/ieee.h new file mode 100644 index 000000000..839dc47d4 --- /dev/null +++ b/mfbt/double-conversion/ieee.h @@ -0,0 +1,398 @@ +// Copyright 2012 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#ifndef DOUBLE_CONVERSION_DOUBLE_H_ +#define DOUBLE_CONVERSION_DOUBLE_H_ + +#include "diy-fp.h" + +namespace double_conversion { + +// We assume that doubles and uint64_t have the same endianness. +static uint64_t double_to_uint64(double d) { return BitCast<uint64_t>(d); } +static double uint64_to_double(uint64_t d64) { return BitCast<double>(d64); } +static uint32_t float_to_uint32(float f) { return BitCast<uint32_t>(f); } +static float uint32_to_float(uint32_t d32) { return BitCast<float>(d32); } + +// Helper functions for doubles. +class Double { + public: + static const uint64_t kSignMask = UINT64_2PART_C(0x80000000, 00000000); + static const uint64_t kExponentMask = UINT64_2PART_C(0x7FF00000, 00000000); + static const uint64_t kSignificandMask = UINT64_2PART_C(0x000FFFFF, FFFFFFFF); + static const uint64_t kHiddenBit = UINT64_2PART_C(0x00100000, 00000000); + static const int kPhysicalSignificandSize = 52; // Excludes the hidden bit. + static const int kSignificandSize = 53; + + Double() : d64_(0) {} + explicit Double(double d) : d64_(double_to_uint64(d)) {} + explicit Double(uint64_t d64) : d64_(d64) {} + explicit Double(DiyFp diy_fp) + : d64_(DiyFpToUint64(diy_fp)) {} + + // The value encoded by this Double must be greater or equal to +0.0. + // It must not be special (infinity, or NaN). + DiyFp AsDiyFp() const { + ASSERT(Sign() > 0); + ASSERT(!IsSpecial()); + return DiyFp(Significand(), Exponent()); + } + + // The value encoded by this Double must be strictly greater than 0. + DiyFp AsNormalizedDiyFp() const { + ASSERT(value() > 0.0); + uint64_t f = Significand(); + int e = Exponent(); + + // The current double could be a denormal. + while ((f & kHiddenBit) == 0) { + f <<= 1; + e--; + } + // Do the final shifts in one go. + f <<= DiyFp::kSignificandSize - kSignificandSize; + e -= DiyFp::kSignificandSize - kSignificandSize; + return DiyFp(f, e); + } + + // Returns the double's bit as uint64. + uint64_t AsUint64() const { + return d64_; + } + + // Returns the next greater double. Returns +infinity on input +infinity. + double NextDouble() const { + if (d64_ == kInfinity) return Double(kInfinity).value(); + if (Sign() < 0 && Significand() == 0) { + // -0.0 + return 0.0; + } + if (Sign() < 0) { + return Double(d64_ - 1).value(); + } else { + return Double(d64_ + 1).value(); + } + } + + double PreviousDouble() const { + if (d64_ == (kInfinity | kSignMask)) return -Double::Infinity(); + if (Sign() < 0) { + return Double(d64_ + 1).value(); + } else { + if (Significand() == 0) return -0.0; + return Double(d64_ - 1).value(); + } + } + + int Exponent() const { + if (IsDenormal()) return kDenormalExponent; + + uint64_t d64 = AsUint64(); + int biased_e = + static_cast<int>((d64 & kExponentMask) >> kPhysicalSignificandSize); + return biased_e - kExponentBias; + } + + uint64_t Significand() const { + uint64_t d64 = AsUint64(); + uint64_t significand = d64 & kSignificandMask; + if (!IsDenormal()) { + return significand + kHiddenBit; + } else { + return significand; + } + } + + // Returns true if the double is a denormal. + bool IsDenormal() const { + uint64_t d64 = AsUint64(); + return (d64 & kExponentMask) == 0; + } + + // We consider denormals not to be special. + // Hence only Infinity and NaN are special. + bool IsSpecial() const { + uint64_t d64 = AsUint64(); + return (d64 & kExponentMask) == kExponentMask; + } + + bool IsNan() const { + uint64_t d64 = AsUint64(); + return ((d64 & kExponentMask) == kExponentMask) && + ((d64 & kSignificandMask) != 0); + } + + bool IsInfinite() const { + uint64_t d64 = AsUint64(); + return ((d64 & kExponentMask) == kExponentMask) && + ((d64 & kSignificandMask) == 0); + } + + int Sign() const { + uint64_t d64 = AsUint64(); + return (d64 & kSignMask) == 0? 1: -1; + } + + // Precondition: the value encoded by this Double must be greater or equal + // than +0.0. + DiyFp UpperBoundary() const { + ASSERT(Sign() > 0); + return DiyFp(Significand() * 2 + 1, Exponent() - 1); + } + + // Computes the two boundaries of this. + // The bigger boundary (m_plus) is normalized. The lower boundary has the same + // exponent as m_plus. + // Precondition: the value encoded by this Double must be greater than 0. + void NormalizedBoundaries(DiyFp* out_m_minus, DiyFp* out_m_plus) const { + ASSERT(value() > 0.0); + DiyFp v = this->AsDiyFp(); + DiyFp m_plus = DiyFp::Normalize(DiyFp((v.f() << 1) + 1, v.e() - 1)); + DiyFp m_minus; + if (LowerBoundaryIsCloser()) { + m_minus = DiyFp((v.f() << 2) - 1, v.e() - 2); + } else { + m_minus = DiyFp((v.f() << 1) - 1, v.e() - 1); + } + m_minus.set_f(m_minus.f() << (m_minus.e() - m_plus.e())); + m_minus.set_e(m_plus.e()); + *out_m_plus = m_plus; + *out_m_minus = m_minus; + } + + bool LowerBoundaryIsCloser() const { + // The boundary is closer if the significand is of the form f == 2^p-1 then + // the lower boundary is closer. + // Think of v = 1000e10 and v- = 9999e9. + // Then the boundary (== (v - v-)/2) is not just at a distance of 1e9 but + // at a distance of 1e8. + // The only exception is for the smallest normal: the largest denormal is + // at the same distance as its successor. + // Note: denormals have the same exponent as the smallest normals. + bool physical_significand_is_zero = ((AsUint64() & kSignificandMask) == 0); + return physical_significand_is_zero && (Exponent() != kDenormalExponent); + } + + double value() const { return uint64_to_double(d64_); } + + // Returns the significand size for a given order of magnitude. + // If v = f*2^e with 2^p-1 <= f <= 2^p then p+e is v's order of magnitude. + // This function returns the number of significant binary digits v will have + // once it's encoded into a double. In almost all cases this is equal to + // kSignificandSize. The only exceptions are denormals. They start with + // leading zeroes and their effective significand-size is hence smaller. + static int SignificandSizeForOrderOfMagnitude(int order) { + if (order >= (kDenormalExponent + kSignificandSize)) { + return kSignificandSize; + } + if (order <= kDenormalExponent) return 0; + return order - kDenormalExponent; + } + + static double Infinity() { + return Double(kInfinity).value(); + } + + static double NaN() { + return Double(kNaN).value(); + } + + private: + static const int kExponentBias = 0x3FF + kPhysicalSignificandSize; + static const int kDenormalExponent = -kExponentBias + 1; + static const int kMaxExponent = 0x7FF - kExponentBias; + static const uint64_t kInfinity = UINT64_2PART_C(0x7FF00000, 00000000); + static const uint64_t kNaN = UINT64_2PART_C(0x7FF80000, 00000000); + + const uint64_t d64_; + + static uint64_t DiyFpToUint64(DiyFp diy_fp) { + uint64_t significand = diy_fp.f(); + int exponent = diy_fp.e(); + while (significand > kHiddenBit + kSignificandMask) { + significand >>= 1; + exponent++; + } + if (exponent >= kMaxExponent) { + return kInfinity; + } + if (exponent < kDenormalExponent) { + return 0; + } + while (exponent > kDenormalExponent && (significand & kHiddenBit) == 0) { + significand <<= 1; + exponent--; + } + uint64_t biased_exponent; + if (exponent == kDenormalExponent && (significand & kHiddenBit) == 0) { + biased_exponent = 0; + } else { + biased_exponent = static_cast<uint64_t>(exponent + kExponentBias); + } + return (significand & kSignificandMask) | + (biased_exponent << kPhysicalSignificandSize); + } +}; + +class Single { + public: + static const uint32_t kSignMask = 0x80000000; + static const uint32_t kExponentMask = 0x7F800000; + static const uint32_t kSignificandMask = 0x007FFFFF; + static const uint32_t kHiddenBit = 0x00800000; + static const int kPhysicalSignificandSize = 23; // Excludes the hidden bit. + static const int kSignificandSize = 24; + + Single() : d32_(0) {} + explicit Single(float f) : d32_(float_to_uint32(f)) {} + explicit Single(uint32_t d32) : d32_(d32) {} + + // The value encoded by this Single must be greater or equal to +0.0. + // It must not be special (infinity, or NaN). + DiyFp AsDiyFp() const { + ASSERT(Sign() > 0); + ASSERT(!IsSpecial()); + return DiyFp(Significand(), Exponent()); + } + + // Returns the single's bit as uint64. + uint32_t AsUint32() const { + return d32_; + } + + int Exponent() const { + if (IsDenormal()) return kDenormalExponent; + + uint32_t d32 = AsUint32(); + int biased_e = + static_cast<int>((d32 & kExponentMask) >> kPhysicalSignificandSize); + return biased_e - kExponentBias; + } + + uint32_t Significand() const { + uint32_t d32 = AsUint32(); + uint32_t significand = d32 & kSignificandMask; + if (!IsDenormal()) { + return significand + kHiddenBit; + } else { + return significand; + } + } + + // Returns true if the single is a denormal. + bool IsDenormal() const { + uint32_t d32 = AsUint32(); + return (d32 & kExponentMask) == 0; + } + + // We consider denormals not to be special. + // Hence only Infinity and NaN are special. + bool IsSpecial() const { + uint32_t d32 = AsUint32(); + return (d32 & kExponentMask) == kExponentMask; + } + + bool IsNan() const { + uint32_t d32 = AsUint32(); + return ((d32 & kExponentMask) == kExponentMask) && + ((d32 & kSignificandMask) != 0); + } + + bool IsInfinite() const { + uint32_t d32 = AsUint32(); + return ((d32 & kExponentMask) == kExponentMask) && + ((d32 & kSignificandMask) == 0); + } + + int Sign() const { + uint32_t d32 = AsUint32(); + return (d32 & kSignMask) == 0? 1: -1; + } + + // Computes the two boundaries of this. + // The bigger boundary (m_plus) is normalized. The lower boundary has the same + // exponent as m_plus. + // Precondition: the value encoded by this Single must be greater than 0. + void NormalizedBoundaries(DiyFp* out_m_minus, DiyFp* out_m_plus) const { + ASSERT(value() > 0.0); + DiyFp v = this->AsDiyFp(); + DiyFp m_plus = DiyFp::Normalize(DiyFp((v.f() << 1) + 1, v.e() - 1)); + DiyFp m_minus; + if (LowerBoundaryIsCloser()) { + m_minus = DiyFp((v.f() << 2) - 1, v.e() - 2); + } else { + m_minus = DiyFp((v.f() << 1) - 1, v.e() - 1); + } + m_minus.set_f(m_minus.f() << (m_minus.e() - m_plus.e())); + m_minus.set_e(m_plus.e()); + *out_m_plus = m_plus; + *out_m_minus = m_minus; + } + + // Precondition: the value encoded by this Single must be greater or equal + // than +0.0. + DiyFp UpperBoundary() const { + ASSERT(Sign() > 0); + return DiyFp(Significand() * 2 + 1, Exponent() - 1); + } + + bool LowerBoundaryIsCloser() const { + // The boundary is closer if the significand is of the form f == 2^p-1 then + // the lower boundary is closer. + // Think of v = 1000e10 and v- = 9999e9. + // Then the boundary (== (v - v-)/2) is not just at a distance of 1e9 but + // at a distance of 1e8. + // The only exception is for the smallest normal: the largest denormal is + // at the same distance as its successor. + // Note: denormals have the same exponent as the smallest normals. + bool physical_significand_is_zero = ((AsUint32() & kSignificandMask) == 0); + return physical_significand_is_zero && (Exponent() != kDenormalExponent); + } + + float value() const { return uint32_to_float(d32_); } + + static float Infinity() { + return Single(kInfinity).value(); + } + + static float NaN() { + return Single(kNaN).value(); + } + + private: + static const int kExponentBias = 0x7F + kPhysicalSignificandSize; + static const int kDenormalExponent = -kExponentBias + 1; + static const int kMaxExponent = 0xFF - kExponentBias; + static const uint32_t kInfinity = 0x7F800000; + static const uint32_t kNaN = 0x7FC00000; + + const uint32_t d32_; +}; + +} // namespace double_conversion + +#endif // DOUBLE_CONVERSION_DOUBLE_H_ diff --git a/mfbt/double-conversion/strtod.cc b/mfbt/double-conversion/strtod.cc new file mode 100644 index 000000000..b097afe0e --- /dev/null +++ b/mfbt/double-conversion/strtod.cc @@ -0,0 +1,555 @@ +// Copyright 2010 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#include <stdarg.h> +#include <limits.h> + +#include "strtod.h" +#include "bignum.h" +#include "cached-powers.h" +#include "ieee.h" + +namespace double_conversion { + +// 2^53 = 9007199254740992. +// Any integer with at most 15 decimal digits will hence fit into a double +// (which has a 53bit significand) without loss of precision. +static const int kMaxExactDoubleIntegerDecimalDigits = 15; +// 2^64 = 18446744073709551616 > 10^19 +static const int kMaxUint64DecimalDigits = 19; + +// Max double: 1.7976931348623157 x 10^308 +// Min non-zero double: 4.9406564584124654 x 10^-324 +// Any x >= 10^309 is interpreted as +infinity. +// Any x <= 10^-324 is interpreted as 0. +// Note that 2.5e-324 (despite being smaller than the min double) will be read +// as non-zero (equal to the min non-zero double). +static const int kMaxDecimalPower = 309; +static const int kMinDecimalPower = -324; + +// 2^64 = 18446744073709551616 +static const uint64_t kMaxUint64 = UINT64_2PART_C(0xFFFFFFFF, FFFFFFFF); + + +static const double exact_powers_of_ten[] = { + 1.0, // 10^0 + 10.0, + 100.0, + 1000.0, + 10000.0, + 100000.0, + 1000000.0, + 10000000.0, + 100000000.0, + 1000000000.0, + 10000000000.0, // 10^10 + 100000000000.0, + 1000000000000.0, + 10000000000000.0, + 100000000000000.0, + 1000000000000000.0, + 10000000000000000.0, + 100000000000000000.0, + 1000000000000000000.0, + 10000000000000000000.0, + 100000000000000000000.0, // 10^20 + 1000000000000000000000.0, + // 10^22 = 0x21e19e0c9bab2400000 = 0x878678326eac9 * 2^22 + 10000000000000000000000.0 +}; +static const int kExactPowersOfTenSize = ARRAY_SIZE(exact_powers_of_ten); + +// Maximum number of significant digits in the decimal representation. +// In fact the value is 772 (see conversions.cc), but to give us some margin +// we round up to 780. +static const int kMaxSignificantDecimalDigits = 780; + +static Vector<const char> TrimLeadingZeros(Vector<const char> buffer) { + for (int i = 0; i < buffer.length(); i++) { + if (buffer[i] != '0') { + return buffer.SubVector(i, buffer.length()); + } + } + return Vector<const char>(buffer.start(), 0); +} + + +static Vector<const char> TrimTrailingZeros(Vector<const char> buffer) { + for (int i = buffer.length() - 1; i >= 0; --i) { + if (buffer[i] != '0') { + return buffer.SubVector(0, i + 1); + } + } + return Vector<const char>(buffer.start(), 0); +} + + +static void CutToMaxSignificantDigits(Vector<const char> buffer, + int exponent, + char* significant_buffer, + int* significant_exponent) { + for (int i = 0; i < kMaxSignificantDecimalDigits - 1; ++i) { + significant_buffer[i] = buffer[i]; + } + // The input buffer has been trimmed. Therefore the last digit must be + // different from '0'. + ASSERT(buffer[buffer.length() - 1] != '0'); + // Set the last digit to be non-zero. This is sufficient to guarantee + // correct rounding. + significant_buffer[kMaxSignificantDecimalDigits - 1] = '1'; + *significant_exponent = + exponent + (buffer.length() - kMaxSignificantDecimalDigits); +} + + +// Trims the buffer and cuts it to at most kMaxSignificantDecimalDigits. +// If possible the input-buffer is reused, but if the buffer needs to be +// modified (due to cutting), then the input needs to be copied into the +// buffer_copy_space. +static void TrimAndCut(Vector<const char> buffer, int exponent, + char* buffer_copy_space, int space_size, + Vector<const char>* trimmed, int* updated_exponent) { + Vector<const char> left_trimmed = TrimLeadingZeros(buffer); + Vector<const char> right_trimmed = TrimTrailingZeros(left_trimmed); + exponent += left_trimmed.length() - right_trimmed.length(); + if (right_trimmed.length() > kMaxSignificantDecimalDigits) { + ASSERT(space_size >= kMaxSignificantDecimalDigits); + CutToMaxSignificantDigits(right_trimmed, exponent, + buffer_copy_space, updated_exponent); + *trimmed = Vector<const char>(buffer_copy_space, + kMaxSignificantDecimalDigits); + } else { + *trimmed = right_trimmed; + *updated_exponent = exponent; + } +} + + +// Reads digits from the buffer and converts them to a uint64. +// Reads in as many digits as fit into a uint64. +// When the string starts with "1844674407370955161" no further digit is read. +// Since 2^64 = 18446744073709551616 it would still be possible read another +// digit if it was less or equal than 6, but this would complicate the code. +static uint64_t ReadUint64(Vector<const char> buffer, + int* number_of_read_digits) { + uint64_t result = 0; + int i = 0; + while (i < buffer.length() && result <= (kMaxUint64 / 10 - 1)) { + int digit = buffer[i++] - '0'; + ASSERT(0 <= digit && digit <= 9); + result = 10 * result + digit; + } + *number_of_read_digits = i; + return result; +} + + +// Reads a DiyFp from the buffer. +// The returned DiyFp is not necessarily normalized. +// If remaining_decimals is zero then the returned DiyFp is accurate. +// Otherwise it has been rounded and has error of at most 1/2 ulp. +static void ReadDiyFp(Vector<const char> buffer, + DiyFp* result, + int* remaining_decimals) { + int read_digits; + uint64_t significand = ReadUint64(buffer, &read_digits); + if (buffer.length() == read_digits) { + *result = DiyFp(significand, 0); + *remaining_decimals = 0; + } else { + // Round the significand. + if (buffer[read_digits] >= '5') { + significand++; + } + // Compute the binary exponent. + int exponent = 0; + *result = DiyFp(significand, exponent); + *remaining_decimals = buffer.length() - read_digits; + } +} + + +static bool DoubleStrtod(Vector<const char> trimmed, + int exponent, + double* result) { +#if !defined(DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS) + // On x86 the floating-point stack can be 64 or 80 bits wide. If it is + // 80 bits wide (as is the case on Linux) then double-rounding occurs and the + // result is not accurate. + // We know that Windows32 uses 64 bits and is therefore accurate. + // Note that the ARM simulator is compiled for 32bits. It therefore exhibits + // the same problem. + return false; +#endif + if (trimmed.length() <= kMaxExactDoubleIntegerDecimalDigits) { + int read_digits; + // The trimmed input fits into a double. + // If the 10^exponent (resp. 10^-exponent) fits into a double too then we + // can compute the result-double simply by multiplying (resp. dividing) the + // two numbers. + // This is possible because IEEE guarantees that floating-point operations + // return the best possible approximation. + if (exponent < 0 && -exponent < kExactPowersOfTenSize) { + // 10^-exponent fits into a double. + *result = static_cast<double>(ReadUint64(trimmed, &read_digits)); + ASSERT(read_digits == trimmed.length()); + *result /= exact_powers_of_ten[-exponent]; + return true; + } + if (0 <= exponent && exponent < kExactPowersOfTenSize) { + // 10^exponent fits into a double. + *result = static_cast<double>(ReadUint64(trimmed, &read_digits)); + ASSERT(read_digits == trimmed.length()); + *result *= exact_powers_of_ten[exponent]; + return true; + } + int remaining_digits = + kMaxExactDoubleIntegerDecimalDigits - trimmed.length(); + if ((0 <= exponent) && + (exponent - remaining_digits < kExactPowersOfTenSize)) { + // The trimmed string was short and we can multiply it with + // 10^remaining_digits. As a result the remaining exponent now fits + // into a double too. + *result = static_cast<double>(ReadUint64(trimmed, &read_digits)); + ASSERT(read_digits == trimmed.length()); + *result *= exact_powers_of_ten[remaining_digits]; + *result *= exact_powers_of_ten[exponent - remaining_digits]; + return true; + } + } + return false; +} + + +// Returns 10^exponent as an exact DiyFp. +// The given exponent must be in the range [1; kDecimalExponentDistance[. +static DiyFp AdjustmentPowerOfTen(int exponent) { + ASSERT(0 < exponent); + ASSERT(exponent < PowersOfTenCache::kDecimalExponentDistance); + // Simply hardcode the remaining powers for the given decimal exponent + // distance. + ASSERT(PowersOfTenCache::kDecimalExponentDistance == 8); + switch (exponent) { + case 1: return DiyFp(UINT64_2PART_C(0xa0000000, 00000000), -60); + case 2: return DiyFp(UINT64_2PART_C(0xc8000000, 00000000), -57); + case 3: return DiyFp(UINT64_2PART_C(0xfa000000, 00000000), -54); + case 4: return DiyFp(UINT64_2PART_C(0x9c400000, 00000000), -50); + case 5: return DiyFp(UINT64_2PART_C(0xc3500000, 00000000), -47); + case 6: return DiyFp(UINT64_2PART_C(0xf4240000, 00000000), -44); + case 7: return DiyFp(UINT64_2PART_C(0x98968000, 00000000), -40); + default: + UNREACHABLE(); + return DiyFp(0, 0); + } +} + + +// If the function returns true then the result is the correct double. +// Otherwise it is either the correct double or the double that is just below +// the correct double. +static bool DiyFpStrtod(Vector<const char> buffer, + int exponent, + double* result) { + DiyFp input; + int remaining_decimals; + ReadDiyFp(buffer, &input, &remaining_decimals); + // Since we may have dropped some digits the input is not accurate. + // If remaining_decimals is different than 0 than the error is at most + // .5 ulp (unit in the last place). + // We don't want to deal with fractions and therefore keep a common + // denominator. + const int kDenominatorLog = 3; + const int kDenominator = 1 << kDenominatorLog; + // Move the remaining decimals into the exponent. + exponent += remaining_decimals; + int error = (remaining_decimals == 0 ? 0 : kDenominator / 2); + + int old_e = input.e(); + input.Normalize(); + error <<= old_e - input.e(); + + ASSERT(exponent <= PowersOfTenCache::kMaxDecimalExponent); + if (exponent < PowersOfTenCache::kMinDecimalExponent) { + *result = 0.0; + return true; + } + DiyFp cached_power; + int cached_decimal_exponent; + PowersOfTenCache::GetCachedPowerForDecimalExponent(exponent, + &cached_power, + &cached_decimal_exponent); + + if (cached_decimal_exponent != exponent) { + int adjustment_exponent = exponent - cached_decimal_exponent; + DiyFp adjustment_power = AdjustmentPowerOfTen(adjustment_exponent); + input.Multiply(adjustment_power); + if (kMaxUint64DecimalDigits - buffer.length() >= adjustment_exponent) { + // The product of input with the adjustment power fits into a 64 bit + // integer. + ASSERT(DiyFp::kSignificandSize == 64); + } else { + // The adjustment power is exact. There is hence only an error of 0.5. + error += kDenominator / 2; + } + } + + input.Multiply(cached_power); + // The error introduced by a multiplication of a*b equals + // error_a + error_b + error_a*error_b/2^64 + 0.5 + // Substituting a with 'input' and b with 'cached_power' we have + // error_b = 0.5 (all cached powers have an error of less than 0.5 ulp), + // error_ab = 0 or 1 / kDenominator > error_a*error_b/ 2^64 + int error_b = kDenominator / 2; + int error_ab = (error == 0 ? 0 : 1); // We round up to 1. + int fixed_error = kDenominator / 2; + error += error_b + error_ab + fixed_error; + + old_e = input.e(); + input.Normalize(); + error <<= old_e - input.e(); + + // See if the double's significand changes if we add/subtract the error. + int order_of_magnitude = DiyFp::kSignificandSize + input.e(); + int effective_significand_size = + Double::SignificandSizeForOrderOfMagnitude(order_of_magnitude); + int precision_digits_count = + DiyFp::kSignificandSize - effective_significand_size; + if (precision_digits_count + kDenominatorLog >= DiyFp::kSignificandSize) { + // This can only happen for very small denormals. In this case the + // half-way multiplied by the denominator exceeds the range of an uint64. + // Simply shift everything to the right. + int shift_amount = (precision_digits_count + kDenominatorLog) - + DiyFp::kSignificandSize + 1; + input.set_f(input.f() >> shift_amount); + input.set_e(input.e() + shift_amount); + // We add 1 for the lost precision of error, and kDenominator for + // the lost precision of input.f(). + error = (error >> shift_amount) + 1 + kDenominator; + precision_digits_count -= shift_amount; + } + // We use uint64_ts now. This only works if the DiyFp uses uint64_ts too. + ASSERT(DiyFp::kSignificandSize == 64); + ASSERT(precision_digits_count < 64); + uint64_t one64 = 1; + uint64_t precision_bits_mask = (one64 << precision_digits_count) - 1; + uint64_t precision_bits = input.f() & precision_bits_mask; + uint64_t half_way = one64 << (precision_digits_count - 1); + precision_bits *= kDenominator; + half_way *= kDenominator; + DiyFp rounded_input(input.f() >> precision_digits_count, + input.e() + precision_digits_count); + if (precision_bits >= half_way + error) { + rounded_input.set_f(rounded_input.f() + 1); + } + // If the last_bits are too close to the half-way case than we are too + // inaccurate and round down. In this case we return false so that we can + // fall back to a more precise algorithm. + + *result = Double(rounded_input).value(); + if (half_way - error < precision_bits && precision_bits < half_way + error) { + // Too imprecise. The caller will have to fall back to a slower version. + // However the returned number is guaranteed to be either the correct + // double, or the next-lower double. + return false; + } else { + return true; + } +} + + +// Returns +// - -1 if buffer*10^exponent < diy_fp. +// - 0 if buffer*10^exponent == diy_fp. +// - +1 if buffer*10^exponent > diy_fp. +// Preconditions: +// buffer.length() + exponent <= kMaxDecimalPower + 1 +// buffer.length() + exponent > kMinDecimalPower +// buffer.length() <= kMaxDecimalSignificantDigits +static int CompareBufferWithDiyFp(Vector<const char> buffer, + int exponent, + DiyFp diy_fp) { + ASSERT(buffer.length() + exponent <= kMaxDecimalPower + 1); + ASSERT(buffer.length() + exponent > kMinDecimalPower); + ASSERT(buffer.length() <= kMaxSignificantDecimalDigits); + // Make sure that the Bignum will be able to hold all our numbers. + // Our Bignum implementation has a separate field for exponents. Shifts will + // consume at most one bigit (< 64 bits). + // ln(10) == 3.3219... + ASSERT(((kMaxDecimalPower + 1) * 333 / 100) < Bignum::kMaxSignificantBits); + Bignum buffer_bignum; + Bignum diy_fp_bignum; + buffer_bignum.AssignDecimalString(buffer); + diy_fp_bignum.AssignUInt64(diy_fp.f()); + if (exponent >= 0) { + buffer_bignum.MultiplyByPowerOfTen(exponent); + } else { + diy_fp_bignum.MultiplyByPowerOfTen(-exponent); + } + if (diy_fp.e() > 0) { + diy_fp_bignum.ShiftLeft(diy_fp.e()); + } else { + buffer_bignum.ShiftLeft(-diy_fp.e()); + } + return Bignum::Compare(buffer_bignum, diy_fp_bignum); +} + + +// Returns true if the guess is the correct double. +// Returns false, when guess is either correct or the next-lower double. +static bool ComputeGuess(Vector<const char> trimmed, int exponent, + double* guess) { + if (trimmed.length() == 0) { + *guess = 0.0; + return true; + } + if (exponent + trimmed.length() - 1 >= kMaxDecimalPower) { + *guess = Double::Infinity(); + return true; + } + if (exponent + trimmed.length() <= kMinDecimalPower) { + *guess = 0.0; + return true; + } + + if (DoubleStrtod(trimmed, exponent, guess) || + DiyFpStrtod(trimmed, exponent, guess)) { + return true; + } + if (*guess == Double::Infinity()) { + return true; + } + return false; +} + +double Strtod(Vector<const char> buffer, int exponent) { + char copy_buffer[kMaxSignificantDecimalDigits]; + Vector<const char> trimmed; + int updated_exponent; + TrimAndCut(buffer, exponent, copy_buffer, kMaxSignificantDecimalDigits, + &trimmed, &updated_exponent); + exponent = updated_exponent; + + double guess; + bool is_correct = ComputeGuess(trimmed, exponent, &guess); + if (is_correct) return guess; + + DiyFp upper_boundary = Double(guess).UpperBoundary(); + int comparison = CompareBufferWithDiyFp(trimmed, exponent, upper_boundary); + if (comparison < 0) { + return guess; + } else if (comparison > 0) { + return Double(guess).NextDouble(); + } else if ((Double(guess).Significand() & 1) == 0) { + // Round towards even. + return guess; + } else { + return Double(guess).NextDouble(); + } +} + +float Strtof(Vector<const char> buffer, int exponent) { + char copy_buffer[kMaxSignificantDecimalDigits]; + Vector<const char> trimmed; + int updated_exponent; + TrimAndCut(buffer, exponent, copy_buffer, kMaxSignificantDecimalDigits, + &trimmed, &updated_exponent); + exponent = updated_exponent; + + double double_guess; + bool is_correct = ComputeGuess(trimmed, exponent, &double_guess); + + float float_guess = static_cast<float>(double_guess); + if (float_guess == double_guess) { + // This shortcut triggers for integer values. + return float_guess; + } + + // We must catch double-rounding. Say the double has been rounded up, and is + // now a boundary of a float, and rounds up again. This is why we have to + // look at previous too. + // Example (in decimal numbers): + // input: 12349 + // high-precision (4 digits): 1235 + // low-precision (3 digits): + // when read from input: 123 + // when rounded from high precision: 124. + // To do this we simply look at the neigbors of the correct result and see + // if they would round to the same float. If the guess is not correct we have + // to look at four values (since two different doubles could be the correct + // double). + + double double_next = Double(double_guess).NextDouble(); + double double_previous = Double(double_guess).PreviousDouble(); + + float f1 = static_cast<float>(double_previous); + float f2 = float_guess; + float f3 = static_cast<float>(double_next); + float f4; + if (is_correct) { + f4 = f3; + } else { + double double_next2 = Double(double_next).NextDouble(); + f4 = static_cast<float>(double_next2); + } + (void) f2; // Mark variable as used. + ASSERT(f1 <= f2 && f2 <= f3 && f3 <= f4); + + // If the guess doesn't lie near a single-precision boundary we can simply + // return its float-value. + if (f1 == f4) { + return float_guess; + } + + ASSERT((f1 != f2 && f2 == f3 && f3 == f4) || + (f1 == f2 && f2 != f3 && f3 == f4) || + (f1 == f2 && f2 == f3 && f3 != f4)); + + // guess and next are the two possible canditates (in the same way that + // double_guess was the lower candidate for a double-precision guess). + float guess = f1; + float next = f4; + DiyFp upper_boundary; + if (guess == 0.0f) { + float min_float = 1e-45f; + upper_boundary = Double(static_cast<double>(min_float) / 2).AsDiyFp(); + } else { + upper_boundary = Single(guess).UpperBoundary(); + } + int comparison = CompareBufferWithDiyFp(trimmed, exponent, upper_boundary); + if (comparison < 0) { + return guess; + } else if (comparison > 0) { + return next; + } else if ((Single(guess).Significand() & 1) == 0) { + // Round towards even. + return guess; + } else { + return next; + } +} + +} // namespace double_conversion diff --git a/mfbt/double-conversion/strtod.h b/mfbt/double-conversion/strtod.h new file mode 100644 index 000000000..ed0293b8f --- /dev/null +++ b/mfbt/double-conversion/strtod.h @@ -0,0 +1,45 @@ +// Copyright 2010 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#ifndef DOUBLE_CONVERSION_STRTOD_H_ +#define DOUBLE_CONVERSION_STRTOD_H_ + +#include "utils.h" + +namespace double_conversion { + +// The buffer must only contain digits in the range [0-9]. It must not +// contain a dot or a sign. It must not start with '0', and must not be empty. +double Strtod(Vector<const char> buffer, int exponent); + +// The buffer must only contain digits in the range [0-9]. It must not +// contain a dot or a sign. It must not start with '0', and must not be empty. +float Strtof(Vector<const char> buffer, int exponent); + +} // namespace double_conversion + +#endif // DOUBLE_CONVERSION_STRTOD_H_ diff --git a/mfbt/double-conversion/update.sh b/mfbt/double-conversion/update.sh new file mode 100755 index 000000000..22233b92b --- /dev/null +++ b/mfbt/double-conversion/update.sh @@ -0,0 +1,23 @@ +# Usage: ./update.sh <double-conversion-src-directory> +# +# Copies the needed files from a directory containing the original +# double-conversion source that we need. + +# This was last updated with git rev 04cae7a8d5ef3d62ceffb03cdc3d38f258457a52. + +set -e + +cp $1/LICENSE ./ +cp $1/README ./ + +# Includes +cp $1/src/*.h ./ + +# Source +cp $1/src/*.cc ./ + +patch -p3 < add-mfbt-api-markers.patch +patch -p3 < use-StandardInteger.patch +patch -p3 < use-mozilla-assertions.patch +patch -p3 < use-static_assert.patch +patch -p3 < ToPrecision-exponential.patch diff --git a/mfbt/double-conversion/use-StandardInteger.patch b/mfbt/double-conversion/use-StandardInteger.patch new file mode 100644 index 000000000..7fe867f43 --- /dev/null +++ b/mfbt/double-conversion/use-StandardInteger.patch @@ -0,0 +1,29 @@ +diff --git a/mfbt/double-conversion/utils.h b/mfbt/double-conversion/utils.h +index cd3e330..bdc7d4b 100644 +--- a/mfbt/double-conversion/utils.h ++++ b/mfbt/double-conversion/utils.h +@@ -74,23 +74,7 @@ + #endif + + +-#if defined(_WIN32) && !defined(__MINGW32__) +- +-typedef signed char int8_t; +-typedef unsigned char uint8_t; +-typedef short int16_t; // NOLINT +-typedef unsigned short uint16_t; // NOLINT +-typedef int int32_t; +-typedef unsigned int uint32_t; +-typedef __int64 int64_t; +-typedef unsigned __int64 uint64_t; +-// intptr_t and friends are defined in crtdefs.h through stdio.h. +- +-#else +- +-#include <stdint.h> +- +-#endif ++#include <stdint.h> + + // The following macro works on both 32 and 64-bit platforms. + // Usage: instead of writing 0x1234567890123456 diff --git a/mfbt/double-conversion/use-mozilla-assertions.patch b/mfbt/double-conversion/use-mozilla-assertions.patch new file mode 100644 index 000000000..c98565f65 --- /dev/null +++ b/mfbt/double-conversion/use-mozilla-assertions.patch @@ -0,0 +1,23 @@ +diff --git a/mfbt/double-conversion/utils.h b/mfbt/double-conversion/utils.h +--- a/mfbt/double-conversion/utils.h ++++ b/mfbt/double-conversion/utils.h +@@ -31,15 +31,15 @@ + #include <stdlib.h> + #include <string.h> + +-#include <assert.h> ++#include "mozilla/Assertions.h" + #ifndef ASSERT +-#define ASSERT(condition) (assert(condition)) ++#define ASSERT(condition) MOZ_ASSERT(condition) + #endif + #ifndef UNIMPLEMENTED +-#define UNIMPLEMENTED() (abort()) ++#define UNIMPLEMENTED() MOZ_CRASH() + #endif + #ifndef UNREACHABLE +-#define UNREACHABLE() (abort()) ++#define UNREACHABLE() MOZ_CRASH() + #endif + + // Double operations detection based on target architecture. diff --git a/mfbt/double-conversion/use-static_assert.patch b/mfbt/double-conversion/use-static_assert.patch new file mode 100644 index 000000000..414378259 --- /dev/null +++ b/mfbt/double-conversion/use-static_assert.patch @@ -0,0 +1,25 @@ +diff --git a/mfbt/double-conversion/utils.h b/mfbt/double-conversion/utils.h +--- a/mfbt/double-conversion/utils.h ++++ b/mfbt/double-conversion/utils.h +@@ -275,19 +275,18 @@ class StringBuilder { + // There is an additional use for BitCast. + // Recent gccs will warn when they see casts that may result in breakage due to + // the type-based aliasing rule. If you have checked that there is no breakage + // you can use BitCast to cast one pointer type to another. This confuses gcc + // enough that it can no longer see that you have cast one pointer type to + // another thus avoiding the warning. + template <class Dest, class Source> + inline Dest BitCast(const Source& source) { +- // Compile time assertion: sizeof(Dest) == sizeof(Source) +- // A compile error here means your Dest and Source have different sizes. +- typedef char VerifySizesAreEqual[sizeof(Dest) == sizeof(Source) ? 1 : -1]; ++ static_assert(sizeof(Dest) == sizeof(Source), ++ "BitCast's source and destination types must be the same size"); + + Dest dest; + memmove(&dest, &source, sizeof(dest)); + return dest; + } + + template <class Dest, class Source> + inline Dest BitCast(Source* source) { diff --git a/mfbt/double-conversion/utils.h b/mfbt/double-conversion/utils.h new file mode 100644 index 000000000..15dd4bfb3 --- /dev/null +++ b/mfbt/double-conversion/utils.h @@ -0,0 +1,298 @@ +// Copyright 2010 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#ifndef DOUBLE_CONVERSION_UTILS_H_ +#define DOUBLE_CONVERSION_UTILS_H_ + +#include <stdlib.h> +#include <string.h> + +#include "mozilla/Assertions.h" +#ifndef ASSERT +#define ASSERT(condition) MOZ_ASSERT(condition) +#endif +#ifndef UNIMPLEMENTED +#define UNIMPLEMENTED() MOZ_CRASH() +#endif +#ifndef UNREACHABLE +#define UNREACHABLE() MOZ_CRASH() +#endif + +// Double operations detection based on target architecture. +// Linux uses a 80bit wide floating point stack on x86. This induces double +// rounding, which in turn leads to wrong results. +// An easy way to test if the floating-point operations are correct is to +// evaluate: 89255.0/1e22. If the floating-point stack is 64 bits wide then +// the result is equal to 89255e-22. +// The best way to test this, is to create a division-function and to compare +// the output of the division with the expected result. (Inlining must be +// disabled.) +// On Linux,x86 89255e-22 != Div_double(89255.0/1e22) +#if defined(_M_X64) || defined(__x86_64__) || \ + defined(__ARMEL__) || defined(__avr32__) || \ + defined(__hppa__) || defined(__ia64__) || \ + defined(__mips__) || \ + defined(__powerpc__) || defined(__ppc__) || defined(__ppc64__) || \ + defined(__sparc__) || defined(__sparc) || defined(__s390__) || \ + defined(__SH4__) || defined(__alpha__) || \ + defined(_MIPS_ARCH_MIPS32R2) || \ + defined(__AARCH64EL__) || defined(__aarch64__) +#define DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS 1 +#elif defined(_M_IX86) || defined(__i386__) || defined(__i386) +#if defined(_WIN32) +// Windows uses a 64bit wide floating point stack. +#define DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS 1 +#else +#undef DOUBLE_CONVERSION_CORRECT_DOUBLE_OPERATIONS +#endif // _WIN32 +#else +#error Target architecture was not detected as supported by Double-Conversion. +#endif + + +#include <stdint.h> + +// The following macro works on both 32 and 64-bit platforms. +// Usage: instead of writing 0x1234567890123456 +// write UINT64_2PART_C(0x12345678,90123456); +#define UINT64_2PART_C(a, b) (((static_cast<uint64_t>(a) << 32) + 0x##b##u)) + + +// The expression ARRAY_SIZE(a) is a compile-time constant of type +// size_t which represents the number of elements of the given +// array. You should only use ARRAY_SIZE on statically allocated +// arrays. +#ifndef ARRAY_SIZE +#define ARRAY_SIZE(a) \ + ((sizeof(a) / sizeof(*(a))) / \ + static_cast<size_t>(!(sizeof(a) % sizeof(*(a))))) +#endif + +// A macro to disallow the evil copy constructor and operator= functions +// This should be used in the private: declarations for a class +#ifndef DISALLOW_COPY_AND_ASSIGN +#define DISALLOW_COPY_AND_ASSIGN(TypeName) \ + TypeName(const TypeName&); \ + void operator=(const TypeName&) +#endif + +// A macro to disallow all the implicit constructors, namely the +// default constructor, copy constructor and operator= functions. +// +// This should be used in the private: declarations for a class +// that wants to prevent anyone from instantiating it. This is +// especially useful for classes containing only static methods. +#ifndef DISALLOW_IMPLICIT_CONSTRUCTORS +#define DISALLOW_IMPLICIT_CONSTRUCTORS(TypeName) \ + TypeName(); \ + DISALLOW_COPY_AND_ASSIGN(TypeName) +#endif + +namespace double_conversion { + +static const int kCharSize = sizeof(char); + +// Returns the maximum of the two parameters. +template <typename T> +static T Max(T a, T b) { + return a < b ? b : a; +} + + +// Returns the minimum of the two parameters. +template <typename T> +static T Min(T a, T b) { + return a < b ? a : b; +} + + +inline int StrLength(const char* string) { + size_t length = strlen(string); + ASSERT(length == static_cast<size_t>(static_cast<int>(length))); + return static_cast<int>(length); +} + +// This is a simplified version of V8's Vector class. +template <typename T> +class Vector { + public: + Vector() : start_(NULL), length_(0) {} + Vector(T* data, int len) : start_(data), length_(len) { + ASSERT(len == 0 || (len > 0 && data != NULL)); + } + + // Returns a vector using the same backing storage as this one, + // spanning from and including 'from', to but not including 'to'. + Vector<T> SubVector(int from, int to) { + ASSERT(to <= length_); + ASSERT(from < to); + ASSERT(0 <= from); + return Vector<T>(start() + from, to - from); + } + + // Returns the length of the vector. + int length() const { return length_; } + + // Returns whether or not the vector is empty. + bool is_empty() const { return length_ == 0; } + + // Returns the pointer to the start of the data in the vector. + T* start() const { return start_; } + + // Access individual vector elements - checks bounds in debug mode. + T& operator[](int index) const { + ASSERT(0 <= index && index < length_); + return start_[index]; + } + + T& first() { return start_[0]; } + + T& last() { return start_[length_ - 1]; } + + private: + T* start_; + int length_; +}; + + +// Helper class for building result strings in a character buffer. The +// purpose of the class is to use safe operations that checks the +// buffer bounds on all operations in debug mode. +class StringBuilder { + public: + StringBuilder(char* buffer, int buffer_size) + : buffer_(buffer, buffer_size), position_(0) { } + + ~StringBuilder() { if (!is_finalized()) Finalize(); } + + int size() const { return buffer_.length(); } + + // Get the current position in the builder. + int position() const { + ASSERT(!is_finalized()); + return position_; + } + + // Reset the position. + void Reset() { position_ = 0; } + + // Add a single character to the builder. It is not allowed to add + // 0-characters; use the Finalize() method to terminate the string + // instead. + void AddCharacter(char c) { + ASSERT(c != '\0'); + ASSERT(!is_finalized() && position_ < buffer_.length()); + buffer_[position_++] = c; + } + + // Add an entire string to the builder. Uses strlen() internally to + // compute the length of the input string. + void AddString(const char* s) { + AddSubstring(s, StrLength(s)); + } + + // Add the first 'n' characters of the given string 's' to the + // builder. The input string must have enough characters. + void AddSubstring(const char* s, int n) { + ASSERT(!is_finalized() && position_ + n < buffer_.length()); + ASSERT(static_cast<size_t>(n) <= strlen(s)); + memmove(&buffer_[position_], s, n * kCharSize); + position_ += n; + } + + + // Add character padding to the builder. If count is non-positive, + // nothing is added to the builder. + void AddPadding(char c, int count) { + for (int i = 0; i < count; i++) { + AddCharacter(c); + } + } + + // Finalize the string by 0-terminating it and returning the buffer. + char* Finalize() { + ASSERT(!is_finalized() && position_ < buffer_.length()); + buffer_[position_] = '\0'; + // Make sure nobody managed to add a 0-character to the + // buffer while building the string. + ASSERT(strlen(buffer_.start()) == static_cast<size_t>(position_)); + position_ = -1; + ASSERT(is_finalized()); + return buffer_.start(); + } + + private: + Vector<char> buffer_; + int position_; + + bool is_finalized() const { return position_ < 0; } + + DISALLOW_IMPLICIT_CONSTRUCTORS(StringBuilder); +}; + +// The type-based aliasing rule allows the compiler to assume that pointers of +// different types (for some definition of different) never alias each other. +// Thus the following code does not work: +// +// float f = foo(); +// int fbits = *(int*)(&f); +// +// The compiler 'knows' that the int pointer can't refer to f since the types +// don't match, so the compiler may cache f in a register, leaving random data +// in fbits. Using C++ style casts makes no difference, however a pointer to +// char data is assumed to alias any other pointer. This is the 'memcpy +// exception'. +// +// Bit_cast uses the memcpy exception to move the bits from a variable of one +// type of a variable of another type. Of course the end result is likely to +// be implementation dependent. Most compilers (gcc-4.2 and MSVC 2005) +// will completely optimize BitCast away. +// +// There is an additional use for BitCast. +// Recent gccs will warn when they see casts that may result in breakage due to +// the type-based aliasing rule. If you have checked that there is no breakage +// you can use BitCast to cast one pointer type to another. This confuses gcc +// enough that it can no longer see that you have cast one pointer type to +// another thus avoiding the warning. +template <class Dest, class Source> +inline Dest BitCast(const Source& source) { + static_assert(sizeof(Dest) == sizeof(Source), + "BitCast's source and destination types must be the same size"); + + Dest dest; + memmove(&dest, &source, sizeof(dest)); + return dest; +} + +template <class Dest, class Source> +inline Dest BitCast(Source* source) { + return BitCast<Dest>(reinterpret_cast<uintptr_t>(source)); +} + +} // namespace double_conversion + +#endif // DOUBLE_CONVERSION_UTILS_H_ diff --git a/mfbt/lz4.c b/mfbt/lz4.c new file mode 100644 index 000000000..c416fe815 --- /dev/null +++ b/mfbt/lz4.c @@ -0,0 +1,1163 @@ +/* + LZ4 - Fast LZ compression algorithm + Copyright (C) 2011-2014, Yann Collet. + BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions are + met: + + * Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above + copyright notice, this list of conditions and the following disclaimer + in the documentation and/or other materials provided with the + distribution. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + + You can contact the author at : + - LZ4 source repository : http://code.google.com/p/lz4/ + - LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c +*/ + +/************************************** + Tuning parameters +**************************************/ +/* + * HEAPMODE : + * Select how default compression functions will allocate memory for their hash table, + * in memory stack (0:default, fastest), or in memory heap (1:requires memory allocation (malloc)). + */ +#define HEAPMODE 0 + + +/************************************** + CPU Feature Detection +**************************************/ +/* 32 or 64 bits ? */ +#if (defined(__x86_64__) || defined(_M_X64) || defined(_WIN64) \ + || defined(__powerpc64__) || defined(__powerpc64le__) \ + || defined(__ppc64__) || defined(__ppc64le__) \ + || defined(__PPC64__) || defined(__PPC64LE__) \ + || defined(__ia64) || defined(__itanium__) || defined(_M_IA64) \ + || (defined(__mips64) && defined(_ABI64))) /* Detects 64 bits mode */ +# define LZ4_ARCH64 1 +#else +# define LZ4_ARCH64 0 +#endif + +/* + * Little Endian or Big Endian ? + * Overwrite the #define below if you know your architecture endianess + */ +#include <stdlib.h> /* Apparently required to detect endianess */ +#if defined (__GLIBC__) +# include <endian.h> +# if (__BYTE_ORDER == __BIG_ENDIAN) +# define LZ4_BIG_ENDIAN 1 +# endif +#elif (defined(__BIG_ENDIAN__) || defined(__BIG_ENDIAN) || defined(_BIG_ENDIAN)) && !(defined(__LITTLE_ENDIAN__) || defined(__LITTLE_ENDIAN) || defined(_LITTLE_ENDIAN)) +# define LZ4_BIG_ENDIAN 1 +#elif defined(__sparc) || defined(__sparc__) \ + || defined(__powerpc__) || defined(__ppc__) || defined(__PPC__) \ + || defined(__hpux) || defined(__hppa) \ + || defined(_MIPSEB) || defined(__s390__) +# define LZ4_BIG_ENDIAN 1 +#else +/* Little Endian assumed. PDP Endian and other very rare endian format are unsupported. */ +#endif + +/* + * Unaligned memory access is automatically enabled for "common" CPU, such as x86. + * For others CPU, such as ARM, the compiler may be more cautious, inserting unnecessary extra code to ensure aligned access property + * If you know your target CPU supports unaligned memory access, you want to force this option manually to improve performance + */ +#if defined(__ARM_FEATURE_UNALIGNED) +# define LZ4_FORCE_UNALIGNED_ACCESS 1 +#endif + +/* Define this parameter if your target system or compiler does not support hardware bit count */ +#if defined(_MSC_VER) && defined(_WIN32_WCE) /* Visual Studio for Windows CE does not support Hardware bit count */ +# define LZ4_FORCE_SW_BITCOUNT +#endif + +/* + * BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE : + * This option may provide a small boost to performance for some big endian cpu, although probably modest. + * You may set this option to 1 if data will remain within closed environment. + * This option is useless on Little_Endian CPU (such as x86) + */ + +/* #define BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE 1 */ + + +/************************************** + Compiler Options +**************************************/ +#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */ +/* "restrict" is a known keyword */ +#else +# define restrict /* Disable restrict */ +#endif + +#ifdef _MSC_VER /* Visual Studio */ +# define FORCE_INLINE static __forceinline +# include <intrin.h> /* For Visual 2005 */ +# if LZ4_ARCH64 /* 64-bits */ +# pragma intrinsic(_BitScanForward64) /* For Visual 2005 */ +# pragma intrinsic(_BitScanReverse64) /* For Visual 2005 */ +# else /* 32-bits */ +# pragma intrinsic(_BitScanForward) /* For Visual 2005 */ +# pragma intrinsic(_BitScanReverse) /* For Visual 2005 */ +# endif +# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */ +#else +# ifdef __GNUC__ +# define FORCE_INLINE static inline __attribute__((always_inline)) +# else +# define FORCE_INLINE static inline +# endif +#endif + +#ifdef _MSC_VER /* Visual Studio */ +# define lz4_bswap16(x) _byteswap_ushort(x) +#else +# define lz4_bswap16(x) ((unsigned short int) ((((x) >> 8) & 0xffu) | (((x) & 0xffu) << 8))) +#endif + +#define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__) + +#if (GCC_VERSION >= 302) || (__INTEL_COMPILER >= 800) || defined(__clang__) +# define expect(expr,value) (__builtin_expect ((expr),(value)) ) +#else +# define expect(expr,value) (expr) +#endif + +#define likely(expr) expect((expr) != 0, 1) +#define unlikely(expr) expect((expr) != 0, 0) + + +/************************************** + Memory routines +**************************************/ +#include <stdlib.h> /* malloc, calloc, free */ +#define ALLOCATOR(n,s) calloc(n,s) +#define FREEMEM free +#include <string.h> /* memset, memcpy */ +#define MEM_INIT memset + + +/************************************** + Includes +**************************************/ +#include "lz4.h" + + +/************************************** + Basic Types +**************************************/ +#if defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */ +# include <stdint.h> + typedef uint8_t BYTE; + typedef uint16_t U16; + typedef uint32_t U32; + typedef int32_t S32; + typedef uint64_t U64; +#else + typedef unsigned char BYTE; + typedef unsigned short U16; + typedef unsigned int U32; + typedef signed int S32; + typedef unsigned long long U64; +#endif + +#if defined(__GNUC__) && !defined(LZ4_FORCE_UNALIGNED_ACCESS) +# define _PACKED __attribute__ ((packed)) +#else +# define _PACKED +#endif + +#if !defined(LZ4_FORCE_UNALIGNED_ACCESS) && !defined(__GNUC__) +# if defined(__IBMC__) || defined(__SUNPRO_C) || defined(__SUNPRO_CC) +# pragma pack(1) +# else +# pragma pack(push, 1) +# endif +#endif + +typedef struct { U16 v; } _PACKED U16_S; +typedef struct { U32 v; } _PACKED U32_S; +typedef struct { U64 v; } _PACKED U64_S; +typedef struct {size_t v;} _PACKED size_t_S; + +#if !defined(LZ4_FORCE_UNALIGNED_ACCESS) && !defined(__GNUC__) +# if defined(__SUNPRO_C) || defined(__SUNPRO_CC) +# pragma pack(0) +# else +# pragma pack(pop) +# endif +#endif + +#define A16(x) (((U16_S *)(x))->v) +#define A32(x) (((U32_S *)(x))->v) +#define A64(x) (((U64_S *)(x))->v) +#define AARCH(x) (((size_t_S *)(x))->v) + + +/************************************** + Constants +**************************************/ +#define LZ4_HASHLOG (LZ4_MEMORY_USAGE-2) +#define HASHTABLESIZE (1 << LZ4_MEMORY_USAGE) +#define HASH_SIZE_U32 (1 << LZ4_HASHLOG) + +#define MINMATCH 4 + +#define COPYLENGTH 8 +#define LASTLITERALS 5 +#define MFLIMIT (COPYLENGTH+MINMATCH) +static const int LZ4_minLength = (MFLIMIT+1); + +#define KB *(1U<<10) +#define MB *(1U<<20) +#define GB *(1U<<30) + +#define LZ4_64KLIMIT ((64 KB) + (MFLIMIT-1)) +#define SKIPSTRENGTH 6 /* Increasing this value will make the compression run slower on incompressible data */ + +#define MAXD_LOG 16 +#define MAX_DISTANCE ((1 << MAXD_LOG) - 1) + +#define ML_BITS 4 +#define ML_MASK ((1U<<ML_BITS)-1) +#define RUN_BITS (8-ML_BITS) +#define RUN_MASK ((1U<<RUN_BITS)-1) + + +/************************************** + Structures and local types +**************************************/ +typedef struct { + U32 hashTable[HASH_SIZE_U32]; + U32 currentOffset; + U32 initCheck; + const BYTE* dictionary; + const BYTE* bufferStart; + U32 dictSize; +} LZ4_stream_t_internal; + +typedef enum { notLimited = 0, limitedOutput = 1 } limitedOutput_directive; +typedef enum { byPtr, byU32, byU16 } tableType_t; + +typedef enum { noDict = 0, withPrefix64k, usingExtDict } dict_directive; +typedef enum { noDictIssue = 0, dictSmall } dictIssue_directive; + +typedef enum { endOnOutputSize = 0, endOnInputSize = 1 } endCondition_directive; +typedef enum { full = 0, partial = 1 } earlyEnd_directive; + + +/************************************** + Architecture-specific macros +**************************************/ +#define STEPSIZE sizeof(size_t) +#define LZ4_COPYSTEP(d,s) { AARCH(d) = AARCH(s); d+=STEPSIZE; s+=STEPSIZE; } +#define LZ4_COPY8(d,s) { LZ4_COPYSTEP(d,s); if (STEPSIZE<8) LZ4_COPYSTEP(d,s); } + +#if (defined(LZ4_BIG_ENDIAN) && !defined(BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE)) +# define LZ4_READ_LITTLEENDIAN_16(d,s,p) { U16 v = A16(p); v = lz4_bswap16(v); d = (s) - v; } +# define LZ4_WRITE_LITTLEENDIAN_16(p,i) { U16 v = (U16)(i); v = lz4_bswap16(v); A16(p) = v; p+=2; } +#else /* Little Endian */ +# define LZ4_READ_LITTLEENDIAN_16(d,s,p) { d = (s) - A16(p); } +# define LZ4_WRITE_LITTLEENDIAN_16(p,v) { A16(p) = v; p+=2; } +#endif + + +/************************************** + Macros +**************************************/ +#define LZ4_STATIC_ASSERT(c) { enum { LZ4_static_assert = 1/(!!(c)) }; } /* use only *after* variable declarations */ +#if LZ4_ARCH64 || !defined(__GNUC__) +# define LZ4_WILDCOPY(d,s,e) { do { LZ4_COPY8(d,s) } while (d<e); } /* at the end, d>=e; */ +#else +# define LZ4_WILDCOPY(d,s,e) { if (likely(e-d <= 8)) LZ4_COPY8(d,s) else do { LZ4_COPY8(d,s) } while (d<e); } +#endif + + +/**************************** + Private local functions +****************************/ +#if LZ4_ARCH64 + +int LZ4_NbCommonBytes (register U64 val) +{ +# if defined(LZ4_BIG_ENDIAN) +# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT) + unsigned long r = 0; + _BitScanReverse64( &r, val ); + return (int)(r>>3); +# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT) + return (__builtin_clzll(val) >> 3); +# else + int r; + if (!(val>>32)) { r=4; } else { r=0; val>>=32; } + if (!(val>>16)) { r+=2; val>>=8; } else { val>>=24; } + r += (!val); + return r; +# endif +# else +# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT) + unsigned long r = 0; + _BitScanForward64( &r, val ); + return (int)(r>>3); +# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT) + return (__builtin_ctzll(val) >> 3); +# else + static const int DeBruijnBytePos[64] = { 0, 0, 0, 0, 0, 1, 1, 2, 0, 3, 1, 3, 1, 4, 2, 7, 0, 2, 3, 6, 1, 5, 3, 5, 1, 3, 4, 4, 2, 5, 6, 7, 7, 0, 1, 2, 3, 3, 4, 6, 2, 6, 5, 5, 3, 4, 5, 6, 7, 1, 2, 4, 6, 4, 4, 5, 7, 2, 6, 5, 7, 6, 7, 7 }; + return DeBruijnBytePos[((U64)((val & -(long long)val) * 0x0218A392CDABBD3FULL)) >> 58]; +# endif +# endif +} + +#else + +int LZ4_NbCommonBytes (register U32 val) +{ +# if defined(LZ4_BIG_ENDIAN) +# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT) + unsigned long r = 0; + _BitScanReverse( &r, val ); + return (int)(r>>3); +# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT) + return (__builtin_clz(val) >> 3); +# else + int r; + if (!(val>>16)) { r=2; val>>=8; } else { r=0; val>>=24; } + r += (!val); + return r; +# endif +# else +# if defined(_MSC_VER) && !defined(LZ4_FORCE_SW_BITCOUNT) + unsigned long r; + _BitScanForward( &r, val ); + return (int)(r>>3); +# elif defined(__GNUC__) && (GCC_VERSION >= 304) && !defined(LZ4_FORCE_SW_BITCOUNT) + return (__builtin_ctz(val) >> 3); +# else + static const int DeBruijnBytePos[32] = { 0, 0, 3, 0, 3, 1, 3, 0, 3, 2, 2, 1, 3, 2, 0, 1, 3, 3, 1, 2, 2, 2, 2, 0, 3, 1, 2, 0, 1, 0, 1, 1 }; + return DeBruijnBytePos[((U32)((val & -(S32)val) * 0x077CB531U)) >> 27]; +# endif +# endif +} + +#endif + + +/******************************** + Compression functions +********************************/ +int LZ4_compressBound(int isize) { return LZ4_COMPRESSBOUND(isize); } + +static int LZ4_hashSequence(U32 sequence, tableType_t tableType) +{ + if (tableType == byU16) + return (((sequence) * 2654435761U) >> ((MINMATCH*8)-(LZ4_HASHLOG+1))); + else + return (((sequence) * 2654435761U) >> ((MINMATCH*8)-LZ4_HASHLOG)); +} + +static int LZ4_hashPosition(const BYTE* p, tableType_t tableType) { return LZ4_hashSequence(A32(p), tableType); } + +static void LZ4_putPositionOnHash(const BYTE* p, U32 h, void* tableBase, tableType_t tableType, const BYTE* srcBase) +{ + switch (tableType) + { + case byPtr: { const BYTE** hashTable = (const BYTE**) tableBase; hashTable[h] = p; break; } + case byU32: { U32* hashTable = (U32*) tableBase; hashTable[h] = (U32)(p-srcBase); break; } + case byU16: { U16* hashTable = (U16*) tableBase; hashTable[h] = (U16)(p-srcBase); break; } + } +} + +static void LZ4_putPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase) +{ + U32 h = LZ4_hashPosition(p, tableType); + LZ4_putPositionOnHash(p, h, tableBase, tableType, srcBase); +} + +static const BYTE* LZ4_getPositionOnHash(U32 h, void* tableBase, tableType_t tableType, const BYTE* srcBase) +{ + if (tableType == byPtr) { const BYTE** hashTable = (const BYTE**) tableBase; return hashTable[h]; } + if (tableType == byU32) { U32* hashTable = (U32*) tableBase; return hashTable[h] + srcBase; } + { U16* hashTable = (U16*) tableBase; return hashTable[h] + srcBase; } /* default, to ensure a return */ +} + +static const BYTE* LZ4_getPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase) +{ + U32 h = LZ4_hashPosition(p, tableType); + return LZ4_getPositionOnHash(h, tableBase, tableType, srcBase); +} + +static unsigned LZ4_count(const BYTE* pIn, const BYTE* pRef, const BYTE* pInLimit) +{ + const BYTE* const pStart = pIn; + + while (likely(pIn<pInLimit-(STEPSIZE-1))) + { + size_t diff = AARCH(pRef) ^ AARCH(pIn); + if (!diff) { pIn+=STEPSIZE; pRef+=STEPSIZE; continue; } + pIn += LZ4_NbCommonBytes(diff); + return (unsigned)(pIn - pStart); + } + if (sizeof(void*)==8) if ((pIn<(pInLimit-3)) && (A32(pRef) == A32(pIn))) { pIn+=4; pRef+=4; } + if ((pIn<(pInLimit-1)) && (A16(pRef) == A16(pIn))) { pIn+=2; pRef+=2; } + if ((pIn<pInLimit) && (*pRef == *pIn)) pIn++; + + return (unsigned)(pIn - pStart); +} + + +static int LZ4_compress_generic( + void* ctx, + const char* source, + char* dest, + int inputSize, + int maxOutputSize, + + limitedOutput_directive outputLimited, + tableType_t tableType, + dict_directive dict, + dictIssue_directive dictIssue) +{ + LZ4_stream_t_internal* const dictPtr = (LZ4_stream_t_internal*)ctx; + + const BYTE* ip = (const BYTE*) source; + const BYTE* base; + const BYTE* lowLimit; + const BYTE* const lowRefLimit = ip - dictPtr->dictSize; + const BYTE* const dictionary = dictPtr->dictionary; + const BYTE* const dictEnd = dictionary + dictPtr->dictSize; + const size_t dictDelta = dictEnd - (const BYTE*)source; + const BYTE* anchor = (const BYTE*) source; + const BYTE* const iend = ip + inputSize; + const BYTE* const mflimit = iend - MFLIMIT; + const BYTE* const matchlimit = iend - LASTLITERALS; + + BYTE* op = (BYTE*) dest; + BYTE* const olimit = op + maxOutputSize; + + const int skipStrength = SKIPSTRENGTH; + U32 forwardH; + size_t refDelta=0; + + /* Init conditions */ + if ((U32)inputSize > (U32)LZ4_MAX_INPUT_SIZE) return 0; /* Unsupported input size, too large (or negative) */ + switch(dict) + { + case noDict: + default: + base = (const BYTE*)source; + lowLimit = (const BYTE*)source; + break; + case withPrefix64k: + base = (const BYTE*)source - dictPtr->currentOffset; + lowLimit = (const BYTE*)source - dictPtr->dictSize; + break; + case usingExtDict: + base = (const BYTE*)source - dictPtr->currentOffset; + lowLimit = (const BYTE*)source; + break; + } + if ((tableType == byU16) && (inputSize>=(int)LZ4_64KLIMIT)) return 0; /* Size too large (not within 64K limit) */ + if (inputSize<LZ4_minLength) goto _last_literals; /* Input too small, no compression (all literals) */ + + /* First Byte */ + LZ4_putPosition(ip, ctx, tableType, base); + ip++; forwardH = LZ4_hashPosition(ip, tableType); + + /* Main Loop */ + for ( ; ; ) + { + const BYTE* ref; + BYTE* token; + { + const BYTE* forwardIp = ip; + unsigned step=1; + unsigned searchMatchNb = (1U << skipStrength); + + /* Find a match */ + do { + U32 h = forwardH; + ip = forwardIp; + forwardIp += step; + step = searchMatchNb++ >> skipStrength; + //if (step>8) step=8; // required for valid forwardIp ; slows down uncompressible data a bit + + if (unlikely(forwardIp > mflimit)) goto _last_literals; + + ref = LZ4_getPositionOnHash(h, ctx, tableType, base); + if (dict==usingExtDict) + { + if (ref<(const BYTE*)source) + { + refDelta = dictDelta; + lowLimit = dictionary; + } + else + { + refDelta = 0; + lowLimit = (const BYTE*)source; + } + } + forwardH = LZ4_hashPosition(forwardIp, tableType); + LZ4_putPositionOnHash(ip, h, ctx, tableType, base); + + } while ( ((dictIssue==dictSmall) ? (ref < lowRefLimit) : 0) + || ((tableType==byU16) ? 0 : (ref + MAX_DISTANCE < ip)) + || (A32(ref+refDelta) != A32(ip)) ); + } + + /* Catch up */ + while ((ip>anchor) && (ref+refDelta > lowLimit) && (unlikely(ip[-1]==ref[refDelta-1]))) { ip--; ref--; } + + { + /* Encode Literal length */ + unsigned litLength = (unsigned)(ip - anchor); + token = op++; + if ((outputLimited) && (unlikely(op + litLength + (2 + 1 + LASTLITERALS) + (litLength/255) > olimit))) + return 0; /* Check output limit */ + if (litLength>=RUN_MASK) + { + int len = (int)litLength-RUN_MASK; + *token=(RUN_MASK<<ML_BITS); + for(; len >= 255 ; len-=255) *op++ = 255; + *op++ = (BYTE)len; + } + else *token = (BYTE)(litLength<<ML_BITS); + + /* Copy Literals */ + { BYTE* end = op+litLength; LZ4_WILDCOPY(op,anchor,end); op=end; } + } + +_next_match: + /* Encode Offset */ + LZ4_WRITE_LITTLEENDIAN_16(op, (U16)(ip-ref)); + + /* Encode MatchLength */ + { + unsigned matchLength; + + if ((dict==usingExtDict) && (lowLimit==dictionary)) + { + const BYTE* limit; + ref += refDelta; + limit = ip + (dictEnd-ref); + if (limit > matchlimit) limit = matchlimit; + matchLength = LZ4_count(ip+MINMATCH, ref+MINMATCH, limit); + ip += MINMATCH + matchLength; + if (ip==limit) + { + unsigned more = LZ4_count(ip, (const BYTE*)source, matchlimit); + matchLength += more; + ip += more; + } + } + else + { + matchLength = LZ4_count(ip+MINMATCH, ref+MINMATCH, matchlimit); + ip += MINMATCH + matchLength; + } + + if (matchLength>=ML_MASK) + { + if ((outputLimited) && (unlikely(op + (1 + LASTLITERALS) + (matchLength>>8) > olimit))) + return 0; /* Check output limit */ + *token += ML_MASK; + matchLength -= ML_MASK; + for (; matchLength >= 510 ; matchLength-=510) { *op++ = 255; *op++ = 255; } + if (matchLength >= 255) { matchLength-=255; *op++ = 255; } + *op++ = (BYTE)matchLength; + } + else *token += (BYTE)(matchLength); + } + + anchor = ip; + + /* Test end of chunk */ + if (ip > mflimit) break; + + /* Fill table */ + LZ4_putPosition(ip-2, ctx, tableType, base); + + /* Test next position */ + ref = LZ4_getPosition(ip, ctx, tableType, base); + if (dict==usingExtDict) + { + if (ref<(const BYTE*)source) + { + refDelta = dictDelta; + lowLimit = dictionary; + } + else + { + refDelta = 0; + lowLimit = (const BYTE*)source; + } + } + LZ4_putPosition(ip, ctx, tableType, base); + if ( ((dictIssue==dictSmall) ? (ref>=lowRefLimit) : 1) + && (ref+MAX_DISTANCE>=ip) + && (A32(ref+refDelta)==A32(ip)) ) + { token=op++; *token=0; goto _next_match; } + + /* Prepare next loop */ + forwardH = LZ4_hashPosition(++ip, tableType); + } + +_last_literals: + /* Encode Last Literals */ + { + int lastRun = (int)(iend - anchor); + if ((outputLimited) && (((char*)op - dest) + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > (U32)maxOutputSize)) + return 0; /* Check output limit */ + if (lastRun>=(int)RUN_MASK) { *op++=(RUN_MASK<<ML_BITS); lastRun-=RUN_MASK; for(; lastRun >= 255 ; lastRun-=255) *op++ = 255; *op++ = (BYTE) lastRun; } + else *op++ = (BYTE)(lastRun<<ML_BITS); + memcpy(op, anchor, iend - anchor); + op += iend-anchor; + } + + /* End */ + return (int) (((char*)op)-dest); +} + + +int LZ4_compress(const char* source, char* dest, int inputSize) +{ +#if (HEAPMODE) + void* ctx = ALLOCATOR(LZ4_STREAMSIZE_U32, 4); /* Aligned on 4-bytes boundaries */ +#else + U32 ctx[LZ4_STREAMSIZE_U32] = {0}; /* Ensure data is aligned on 4-bytes boundaries */ +#endif + int result; + + if (inputSize < (int)LZ4_64KLIMIT) + result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, 0, notLimited, byU16, noDict, noDictIssue); + else + result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, 0, notLimited, (sizeof(void*)==8) ? byU32 : byPtr, noDict, noDictIssue); + +#if (HEAPMODE) + FREEMEM(ctx); +#endif + return result; +} + +int LZ4_compress_limitedOutput(const char* source, char* dest, int inputSize, int maxOutputSize) +{ +#if (HEAPMODE) + void* ctx = ALLOCATOR(LZ4_STREAMSIZE_U32, 4); /* Aligned on 4-bytes boundaries */ +#else + U32 ctx[LZ4_STREAMSIZE_U32] = {0}; /* Ensure data is aligned on 4-bytes boundaries */ +#endif + int result; + + if (inputSize < (int)LZ4_64KLIMIT) + result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue); + else + result = LZ4_compress_generic((void*)ctx, source, dest, inputSize, maxOutputSize, limitedOutput, (sizeof(void*)==8) ? byU32 : byPtr, noDict, noDictIssue); + +#if (HEAPMODE) + FREEMEM(ctx); +#endif + return result; +} + + +/***************************************** + Experimental : Streaming functions +*****************************************/ + +void* LZ4_createStream() +{ + void* lz4s = ALLOCATOR(4, LZ4_STREAMSIZE_U32); + MEM_INIT(lz4s, 0, LZ4_STREAMSIZE); + return lz4s; +} + +int LZ4_free (void* LZ4_stream) +{ + FREEMEM(LZ4_stream); + return (0); +} + + +int LZ4_loadDict (void* LZ4_dict, const char* dictionary, int dictSize) +{ + LZ4_stream_t_internal* dict = (LZ4_stream_t_internal*) LZ4_dict; + const BYTE* p = (const BYTE*)dictionary; + const BYTE* const dictEnd = p + dictSize; + const BYTE* base; + + LZ4_STATIC_ASSERT(LZ4_STREAMSIZE >= sizeof(LZ4_stream_t_internal)); /* A compilation error here means LZ4_STREAMSIZE is not large enough */ + if (dict->initCheck) MEM_INIT(dict, 0, sizeof(LZ4_stream_t_internal)); /* Uninitialized structure detected */ + + if (dictSize < MINMATCH) + { + dict->dictionary = NULL; + dict->dictSize = 0; + return 1; + } + + if (p <= dictEnd - 64 KB) p = dictEnd - 64 KB; + base = p - dict->currentOffset; + dict->dictionary = p; + dict->dictSize = (U32)(dictEnd - p); + dict->currentOffset += dict->dictSize; + + while (p <= dictEnd-MINMATCH) + { + LZ4_putPosition(p, dict, byU32, base); + p+=3; + } + + return 1; +} + + +void LZ4_renormDictT(LZ4_stream_t_internal* LZ4_dict, const BYTE* src) +{ + if ((LZ4_dict->currentOffset > 0x80000000) || + ((size_t)LZ4_dict->currentOffset > (size_t)src)) /* address space overflow */ + { + /* rescale hash table */ + U32 delta = LZ4_dict->currentOffset - 64 KB; + const BYTE* dictEnd = LZ4_dict->dictionary + LZ4_dict->dictSize; + int i; + for (i=0; i<HASH_SIZE_U32; i++) + { + if (LZ4_dict->hashTable[i] < delta) LZ4_dict->hashTable[i]=0; + else LZ4_dict->hashTable[i] -= delta; + } + LZ4_dict->currentOffset = 64 KB; + if (LZ4_dict->dictSize > 64 KB) LZ4_dict->dictSize = 64 KB; + LZ4_dict->dictionary = dictEnd - LZ4_dict->dictSize; + } +} + + +FORCE_INLINE int LZ4_compress_continue_generic (void* LZ4_stream, const char* source, char* dest, int inputSize, + int maxOutputSize, limitedOutput_directive limit) +{ + LZ4_stream_t_internal* streamPtr = (LZ4_stream_t_internal*)LZ4_stream; + const BYTE* const dictEnd = streamPtr->dictionary + streamPtr->dictSize; + + const BYTE* smallest = (const BYTE*) source; + if (streamPtr->initCheck) return 0; /* Uninitialized structure detected */ + if ((streamPtr->dictSize>0) && (smallest>dictEnd)) smallest = dictEnd; + LZ4_renormDictT(streamPtr, smallest); + + /* Check overlapping input/dictionary space */ + { + const BYTE* sourceEnd = (const BYTE*) source + inputSize; + if ((sourceEnd > streamPtr->dictionary) && (sourceEnd < dictEnd)) + { + streamPtr->dictSize = (U32)(dictEnd - sourceEnd); + if (streamPtr->dictSize > 64 KB) streamPtr->dictSize = 64 KB; + if (streamPtr->dictSize < 4) streamPtr->dictSize = 0; + streamPtr->dictionary = dictEnd - streamPtr->dictSize; + } + } + + /* prefix mode : source data follows dictionary */ + if (dictEnd == (const BYTE*)source) + { + int result; + if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset)) + result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limit, byU32, withPrefix64k, dictSmall); + else + result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limit, byU32, withPrefix64k, noDictIssue); + streamPtr->dictSize += (U32)inputSize; + streamPtr->currentOffset += (U32)inputSize; + return result; + } + + /* external dictionary mode */ + { + int result; + if ((streamPtr->dictSize < 64 KB) && (streamPtr->dictSize < streamPtr->currentOffset)) + result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limit, byU32, usingExtDict, dictSmall); + else + result = LZ4_compress_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limit, byU32, usingExtDict, noDictIssue); + streamPtr->dictionary = (const BYTE*)source; + streamPtr->dictSize = (U32)inputSize; + streamPtr->currentOffset += (U32)inputSize; + return result; + } +} + + +int LZ4_compress_continue (void* LZ4_stream, const char* source, char* dest, int inputSize) +{ + return LZ4_compress_continue_generic(LZ4_stream, source, dest, inputSize, 0, notLimited); +} + +int LZ4_compress_limitedOutput_continue (void* LZ4_stream, const char* source, char* dest, int inputSize, int maxOutputSize) +{ + return LZ4_compress_continue_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limitedOutput); +} + + +// Hidden debug function, to force separate dictionary mode +int LZ4_compress_forceExtDict (LZ4_stream_t* LZ4_dict, const char* source, char* dest, int inputSize) +{ + LZ4_stream_t_internal* streamPtr = (LZ4_stream_t_internal*)LZ4_dict; + int result; + const BYTE* const dictEnd = streamPtr->dictionary + streamPtr->dictSize; + + const BYTE* smallest = dictEnd; + if (smallest > (const BYTE*) source) smallest = (const BYTE*) source; + LZ4_renormDictT((LZ4_stream_t_internal*)LZ4_dict, smallest); + + result = LZ4_compress_generic(LZ4_dict, source, dest, inputSize, 0, notLimited, byU32, usingExtDict, noDictIssue); + + streamPtr->dictionary = (const BYTE*)source; + streamPtr->dictSize = (U32)inputSize; + streamPtr->currentOffset += (U32)inputSize; + + return result; +} + + +int LZ4_saveDict (void* LZ4_dict, char* safeBuffer, int dictSize) +{ + LZ4_stream_t_internal* dict = (LZ4_stream_t_internal*) LZ4_dict; + const BYTE* previousDictEnd = dict->dictionary + dict->dictSize; + + if ((U32)dictSize > 64 KB) dictSize = 64 KB; /* useless to define a dictionary > 64 KB */ + if ((U32)dictSize > dict->dictSize) dictSize = dict->dictSize; + + memcpy(safeBuffer, previousDictEnd - dictSize, dictSize); + + dict->dictionary = (const BYTE*)safeBuffer; + dict->dictSize = (U32)dictSize; + + return 1; +} + + + +/**************************** + Decompression functions +****************************/ +/* + * This generic decompression function cover all use cases. + * It shall be instanciated several times, using different sets of directives + * Note that it is essential this generic function is really inlined, + * in order to remove useless branches during compilation optimisation. + */ +FORCE_INLINE int LZ4_decompress_generic( + const char* source, + char* dest, + int inputSize, + int outputSize, /* If endOnInput==endOnInputSize, this value is the max size of Output Buffer. */ + + int endOnInput, /* endOnOutputSize, endOnInputSize */ + int partialDecoding, /* full, partial */ + int targetOutputSize, /* only used if partialDecoding==partial */ + int dict, /* noDict, withPrefix64k, usingExtDict */ + const char* dictStart, /* only if dict==usingExtDict */ + int dictSize /* note : = 0 if noDict */ + ) +{ + /* Local Variables */ + const BYTE* restrict ip = (const BYTE*) source; + const BYTE* ref; + const BYTE* const iend = ip + inputSize; + + BYTE* op = (BYTE*) dest; + BYTE* const oend = op + outputSize; + BYTE* cpy; + BYTE* oexit = op + targetOutputSize; + const BYTE* const lowLimit = (const BYTE*)dest - dictSize; + + const BYTE* const dictEnd = (const BYTE*)dictStart + dictSize; +//#define OLD +#ifdef OLD + const size_t dec32table[] = {0, 3, 2, 3, 0, 0, 0, 0}; /* static reduces speed for LZ4_decompress_safe() on GCC64 */ +#else + const size_t dec32table[] = {4-0, 4-3, 4-2, 4-3, 4-0, 4-0, 4-0, 4-0}; /* static reduces speed for LZ4_decompress_safe() on GCC64 */ +#endif + static const size_t dec64table[] = {0, 0, 0, (size_t)-1, 0, 1, 2, 3}; + + const int checkOffset = (endOnInput) && (dictSize < (int)(64 KB)); + + + /* Special cases */ + if ((partialDecoding) && (oexit> oend-MFLIMIT)) oexit = oend-MFLIMIT; /* targetOutputSize too high => decode everything */ + if ((endOnInput) && (unlikely(outputSize==0))) return ((inputSize==1) && (*ip==0)) ? 0 : -1; /* Empty output buffer */ + if ((!endOnInput) && (unlikely(outputSize==0))) return (*ip==0?1:-1); + + + /* Main Loop */ + while (1) + { + unsigned token; + size_t length; + + /* get runlength */ + token = *ip++; + if ((length=(token>>ML_BITS)) == RUN_MASK) + { + unsigned s; + do + { + s = *ip++; + length += s; + } + while (likely((endOnInput)?ip<iend-RUN_MASK:1) && (s==255)); + //if ((sizeof(void*)==4) && unlikely(length>LZ4_MAX_INPUT_SIZE)) goto _output_error; /* overflow detection */ + if ((sizeof(void*)==4) && unlikely((size_t)(op+length)<(size_t)(op))) goto _output_error; /* quickfix issue 134 */ + if ((endOnInput) && (sizeof(void*)==4) && unlikely((size_t)(ip+length)<(size_t)(ip))) goto _output_error; /* quickfix issue 134 */ + } + + /* copy literals */ + cpy = op+length; + if (((endOnInput) && ((cpy>(partialDecoding?oexit:oend-MFLIMIT)) || (ip+length>iend-(2+1+LASTLITERALS))) ) + || ((!endOnInput) && (cpy>oend-COPYLENGTH))) + { + if (partialDecoding) + { + if (cpy > oend) goto _output_error; /* Error : write attempt beyond end of output buffer */ + if ((endOnInput) && (ip+length > iend)) goto _output_error; /* Error : read attempt beyond end of input buffer */ + } + else + { + if ((!endOnInput) && (cpy != oend)) goto _output_error; /* Error : block decoding must stop exactly there */ + if ((endOnInput) && ((ip+length != iend) || (cpy > oend))) goto _output_error; /* Error : input must be consumed */ + } + memcpy(op, ip, length); + ip += length; + op += length; + break; /* Necessarily EOF, due to parsing restrictions */ + } + LZ4_WILDCOPY(op, ip, cpy); ip -= (op-cpy); op = cpy; + + /* get offset */ + LZ4_READ_LITTLEENDIAN_16(ref,cpy,ip); ip+=2; + if ((checkOffset) && (unlikely(ref < lowLimit))) goto _output_error; /* Error : offset outside destination buffer */ + + /* get matchlength */ + if ((length=(token&ML_MASK)) == ML_MASK) + { + unsigned s; + do + { + if ((endOnInput) && (ip > iend-LASTLITERALS)) goto _output_error; + s = *ip++; + length += s; + } while (s==255); + //if ((sizeof(void*)==4) && unlikely(length>LZ4_MAX_INPUT_SIZE)) goto _output_error; /* overflow detection */ + if ((sizeof(void*)==4) && unlikely((size_t)(op+length)<(size_t)op)) goto _output_error; /* quickfix issue 134 */ + } + + /* check external dictionary */ + if ((dict==usingExtDict) && (ref < (BYTE* const)dest)) + { + if (unlikely(op+length+MINMATCH > oend-LASTLITERALS)) goto _output_error; + + if (length+MINMATCH <= (size_t)(dest-(char*)ref)) + { + ref = dictEnd - (dest-(char*)ref); + memcpy(op, ref, length+MINMATCH); + op += length+MINMATCH; + } + else + { + size_t copySize = (size_t)(dest-(char*)ref); + memcpy(op, dictEnd - copySize, copySize); + op += copySize; + copySize = length+MINMATCH - copySize; + if (copySize > (size_t)((char*)op-dest)) /* overlap */ + { + BYTE* const cpy = op + copySize; + const BYTE* ref = (BYTE*)dest; + while (op < cpy) *op++ = *ref++; + } + else + { + memcpy(op, dest, copySize); + op += copySize; + } + } + continue; + } + + /* copy repeated sequence */ + if (unlikely((op-ref)<(int)STEPSIZE)) + { + const size_t dec64 = dec64table[(sizeof(void*)==4) ? 0 : op-ref]; + op[0] = ref[0]; + op[1] = ref[1]; + op[2] = ref[2]; + op[3] = ref[3]; +#ifdef OLD + op += 4, ref += 4; ref -= dec32table[op-ref]; + A32(op) = A32(ref); + op += STEPSIZE-4; ref -= dec64; +#else + ref += dec32table[op-ref]; + A32(op+4) = A32(ref); + op += STEPSIZE; ref -= dec64; +#endif + } else { LZ4_COPYSTEP(op,ref); } + cpy = op + length - (STEPSIZE-4); + + if (unlikely(cpy>oend-COPYLENGTH-(STEPSIZE-4))) + { + if (cpy > oend-LASTLITERALS) goto _output_error; /* Error : last 5 bytes must be literals */ + if (op<oend-COPYLENGTH) LZ4_WILDCOPY(op, ref, (oend-COPYLENGTH)); + while(op<cpy) *op++=*ref++; + op=cpy; + continue; + } + LZ4_WILDCOPY(op, ref, cpy); + op=cpy; /* correction */ + } + + /* end of decoding */ + if (endOnInput) + return (int) (((char*)op)-dest); /* Nb of output bytes decoded */ + else + return (int) (((char*)ip)-source); /* Nb of input bytes read */ + + /* Overflow error detected */ +_output_error: + return (int) (-(((char*)ip)-source))-1; +} + + +int LZ4_decompress_safe(const char* source, char* dest, int compressedSize, int maxOutputSize) +{ + return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, endOnInputSize, full, 0, noDict, NULL, 0); +} + +int LZ4_decompress_safe_partial(const char* source, char* dest, int compressedSize, int targetOutputSize, int maxOutputSize) +{ + return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, endOnInputSize, partial, targetOutputSize, noDict, NULL, 0); +} + +int LZ4_decompress_fast(const char* source, char* dest, int originalSize) +{ + return LZ4_decompress_generic(source, dest, 0, originalSize, endOnOutputSize, full, 0, withPrefix64k, NULL, 0); +} + +/* streaming decompression functions */ + +//#define LZ4_STREAMDECODESIZE_U32 4 +//#define LZ4_STREAMDECODESIZE (LZ4_STREAMDECODESIZE_U32 * sizeof(unsigned int)) +//typedef struct { unsigned int table[LZ4_STREAMDECODESIZE_U32]; } LZ4_streamDecode_t; +typedef struct +{ + const char* dictionary; + int dictSize; +} LZ4_streamDecode_t_internal; + +/* + * If you prefer dynamic allocation methods, + * LZ4_createStreamDecode() + * provides a pointer (void*) towards an initialized LZ4_streamDecode_t structure. + */ +void* LZ4_createStreamDecode() +{ + void* lz4s = ALLOCATOR(sizeof(U32), LZ4_STREAMDECODESIZE_U32); + MEM_INIT(lz4s, 0, LZ4_STREAMDECODESIZE); + return lz4s; +} + +/* + * LZ4_setDictDecode + * Use this function to instruct where to find the dictionary + * This function is not necessary if previous data is still available where it was decoded. + * Loading a size of 0 is allowed (same effect as no dictionary). + * Return : 1 if OK, 0 if error + */ +int LZ4_setDictDecode (void* LZ4_streamDecode, const char* dictionary, int dictSize) +{ + LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*) LZ4_streamDecode; + lz4sd->dictionary = dictionary; + lz4sd->dictSize = dictSize; + return 1; +} + +/* +*_continue() : + These decoding functions allow decompression of multiple blocks in "streaming" mode. + Previously decoded blocks must still be available at the memory position where they were decoded. + If it's not possible, save the relevant part of decoded data into a safe buffer, + and indicate where it stands using LZ4_setDictDecode() +*/ +int LZ4_decompress_safe_continue (void* LZ4_streamDecode, const char* source, char* dest, int compressedSize, int maxOutputSize) +{ + LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*) LZ4_streamDecode; + int result; + + result = LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, endOnInputSize, full, 0, usingExtDict, lz4sd->dictionary, lz4sd->dictSize); + if (result <= 0) return result; + if (lz4sd->dictionary + lz4sd->dictSize == dest) + { + lz4sd->dictSize += result; + } + else + { + lz4sd->dictionary = dest; + lz4sd->dictSize = result; + } + + return result; +} + +int LZ4_decompress_fast_continue (void* LZ4_streamDecode, const char* source, char* dest, int originalSize) +{ + LZ4_streamDecode_t_internal* lz4sd = (LZ4_streamDecode_t_internal*) LZ4_streamDecode; + int result; + + result = LZ4_decompress_generic(source, dest, 0, originalSize, endOnOutputSize, full, 0, usingExtDict, lz4sd->dictionary, lz4sd->dictSize); + if (result <= 0) return result; + if (lz4sd->dictionary + lz4sd->dictSize == dest) + { + lz4sd->dictSize += result; + } + else + { + lz4sd->dictionary = dest; + lz4sd->dictSize = result; + } + + return result; +} + + +/* +Advanced decoding functions : +*_usingDict() : + These decoding functions work the same as "_continue" ones, + the dictionary must be explicitly provided within parameters +*/ + +int LZ4_decompress_safe_usingDict(const char* source, char* dest, int compressedSize, int maxOutputSize, const char* dictStart, int dictSize) +{ + return LZ4_decompress_generic(source, dest, compressedSize, maxOutputSize, endOnInputSize, full, 0, usingExtDict, dictStart, dictSize); +} + +int LZ4_decompress_fast_usingDict(const char* source, char* dest, int originalSize, const char* dictStart, int dictSize) +{ + return LZ4_decompress_generic(source, dest, 0, originalSize, endOnOutputSize, full, 0, usingExtDict, dictStart, dictSize); +} diff --git a/mfbt/lz4.h b/mfbt/lz4.h new file mode 100644 index 000000000..bf6780122 --- /dev/null +++ b/mfbt/lz4.h @@ -0,0 +1,276 @@ +/* + LZ4 - Fast LZ compression algorithm + Header File + Copyright (C) 2011-2014, Yann Collet. + BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions are + met: + + * Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above + copyright notice, this list of conditions and the following disclaimer + in the documentation and/or other materials provided with the + distribution. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + + You can contact the author at : + - LZ4 source repository : http://code.google.com/p/lz4/ + - LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c +*/ +#pragma once + +#if defined (__cplusplus) +extern "C" { +#endif + + +/************************************** + Version +**************************************/ +#define LZ4_VERSION_MAJOR 1 /* for major interface/format changes */ +#define LZ4_VERSION_MINOR 2 /* for minor interface/format changes */ +#define LZ4_VERSION_RELEASE 0 /* for tweaks, bug-fixes, or development */ + + +/************************************** + Tuning parameter +**************************************/ +/* + * LZ4_MEMORY_USAGE : + * Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.) + * Increasing memory usage improves compression ratio + * Reduced memory usage can improve speed, due to cache effect + * Default value is 14, for 16KB, which nicely fits into Intel x86 L1 cache + */ +#define LZ4_MEMORY_USAGE 14 + + +/************************************** + Simple Functions +**************************************/ + +int LZ4_compress (const char* source, char* dest, int inputSize); +int LZ4_decompress_safe (const char* source, char* dest, int compressedSize, int maxOutputSize); + +/* +LZ4_compress() : + Compresses 'inputSize' bytes from 'source' into 'dest'. + Destination buffer must be already allocated, + and must be sized to handle worst cases situations (input data not compressible) + Worst case size evaluation is provided by function LZ4_compressBound() + inputSize : Max supported value is LZ4_MAX_INPUT_VALUE + return : the number of bytes written in buffer dest + or 0 if the compression fails + +LZ4_decompress_safe() : + compressedSize : is obviously the source size + maxOutputSize : is the size of the destination buffer, which must be already allocated. + return : the number of bytes decoded in the destination buffer (necessarily <= maxOutputSize) + If the destination buffer is not large enough, decoding will stop and output an error code (<0). + If the source stream is detected malformed, the function will stop decoding and return a negative result. + This function is protected against buffer overflow exploits : + it never writes outside of output buffer, and never reads outside of input buffer. + Therefore, it is protected against malicious data packets. +*/ + + +/* +Note : + Should you prefer to explicitly allocate compression-table memory using your own allocation method, + use the streaming functions provided below, simply reset the memory area between each call to LZ4_compress_continue() +*/ + + +/************************************** + Advanced Functions +**************************************/ +#define LZ4_MAX_INPUT_SIZE 0x7E000000 /* 2 113 929 216 bytes */ +#define LZ4_COMPRESSBOUND(isize) ((unsigned int)(isize) > (unsigned int)LZ4_MAX_INPUT_SIZE ? 0 : (isize) + ((isize)/255) + 16) + +/* +LZ4_compressBound() : + Provides the maximum size that LZ4 may output in a "worst case" scenario (input data not compressible) + primarily useful for memory allocation of output buffer. + macro is also provided when result needs to be evaluated at compilation (such as stack memory allocation). + + isize : is the input size. Max supported value is LZ4_MAX_INPUT_SIZE + return : maximum output size in a "worst case" scenario + or 0, if input size is too large ( > LZ4_MAX_INPUT_SIZE) +*/ +int LZ4_compressBound(int isize); + + +/* +LZ4_compress_limitedOutput() : + Compress 'inputSize' bytes from 'source' into an output buffer 'dest' of maximum size 'maxOutputSize'. + If it cannot achieve it, compression will stop, and result of the function will be zero. + This function never writes outside of provided output buffer. + + inputSize : Max supported value is LZ4_MAX_INPUT_VALUE + maxOutputSize : is the size of the destination buffer (which must be already allocated) + return : the number of bytes written in buffer 'dest' + or 0 if the compression fails +*/ +int LZ4_compress_limitedOutput (const char* source, char* dest, int inputSize, int maxOutputSize); + + +/* +LZ4_decompress_fast() : + originalSize : is the original and therefore uncompressed size + return : the number of bytes read from the source buffer (in other words, the compressed size) + If the source stream is malformed, the function will stop decoding and return a negative result. + Destination buffer must be already allocated. Its size must be a minimum of 'originalSize' bytes. + note : This function is a bit faster than LZ4_decompress_safe() + It provides fast decompression and fully respect memory boundaries for properly formed compressed data. + It does not provide full protection against intentionnally modified data stream. + Use this function in a trusted environment (data to decode comes from a trusted source). +*/ +int LZ4_decompress_fast (const char* source, char* dest, int originalSize); + + +/* +LZ4_decompress_safe_partial() : + This function decompress a compressed block of size 'compressedSize' at position 'source' + into output buffer 'dest' of size 'maxOutputSize'. + The function tries to stop decompressing operation as soon as 'targetOutputSize' has been reached, + reducing decompression time. + return : the number of bytes decoded in the destination buffer (necessarily <= maxOutputSize) + Note : this number can be < 'targetOutputSize' should the compressed block to decode be smaller. + Always control how many bytes were decoded. + If the source stream is detected malformed, the function will stop decoding and return a negative result. + This function never writes outside of output buffer, and never reads outside of input buffer. It is therefore protected against malicious data packets +*/ +int LZ4_decompress_safe_partial (const char* source, char* dest, int compressedSize, int targetOutputSize, int maxOutputSize); + + +/*********************************************** + Experimental Streaming Compression Functions +***********************************************/ + +#define LZ4_STREAMSIZE_U32 ((1 << (LZ4_MEMORY_USAGE-2)) + 8) +#define LZ4_STREAMSIZE (LZ4_STREAMSIZE_U32 * sizeof(unsigned int)) +/* + * LZ4_stream_t + * information structure to track an LZ4 stream. + * important : set this structure content to zero before first use ! + */ +typedef struct { unsigned int table[LZ4_STREAMSIZE_U32]; } LZ4_stream_t; + +/* + * If you prefer dynamic allocation methods, + * LZ4_createStream + * provides a pointer (void*) towards an initialized LZ4_stream_t structure. + * LZ4_free just frees it. + */ +void* LZ4_createStream(); +int LZ4_free (void* LZ4_stream); + + +/* + * LZ4_loadDict + * Use this function to load a static dictionary into LZ4_stream. + * Any previous data will be forgotten, only 'dictionary' will remain in memory. + * Loading a size of 0 is allowed (same effect as init). + * Return : 1 if OK, 0 if error + */ +int LZ4_loadDict (void* LZ4_stream, const char* dictionary, int dictSize); + +/* + * LZ4_compress_continue + * Compress data block 'source', using blocks compressed before as dictionary to improve compression ratio + * Previous data blocks are assumed to still be present at their previous location. + */ +int LZ4_compress_continue (void* LZ4_stream, const char* source, char* dest, int inputSize); + +/* + * LZ4_compress_limitedOutput_continue + * Same as before, but also specify a maximum target compressed size (maxOutputSize) + * If objective cannot be met, compression exits, and returns a zero. + */ +int LZ4_compress_limitedOutput_continue (void* LZ4_stream, const char* source, char* dest, int inputSize, int maxOutputSize); + +/* + * LZ4_saveDict + * If previously compressed data block is not guaranteed to remain at its previous memory location + * save it into a safe place (char* safeBuffer) + * Note : you don't need to call LZ4_loadDict() afterwards, + * dictionary is immediately usable, you can therefore call again LZ4_compress_continue() + * Return : 1 if OK, 0 if error + * Note : any dictSize > 64 KB will be interpreted as 64KB. + */ +int LZ4_saveDict (void* LZ4_stream, char* safeBuffer, int dictSize); + + +/************************************************ + Experimental Streaming Decompression Functions +************************************************/ + +#define LZ4_STREAMDECODESIZE_U32 4 +#define LZ4_STREAMDECODESIZE (LZ4_STREAMDECODESIZE_U32 * sizeof(unsigned int)) +/* + * LZ4_streamDecode_t + * information structure to track an LZ4 stream. + * important : set this structure content to zero before first use ! + */ +typedef struct { unsigned int table[LZ4_STREAMDECODESIZE_U32]; } LZ4_streamDecode_t; + +/* + * If you prefer dynamic allocation methods, + * LZ4_createStreamDecode() + * provides a pointer (void*) towards an initialized LZ4_streamDecode_t structure. + * LZ4_free just frees it. + */ +void* LZ4_createStreamDecode(); +int LZ4_free (void* LZ4_stream); /* yes, it's the same one as for compression */ + +/* +*_continue() : + These decoding functions allow decompression of multiple blocks in "streaming" mode. + Previously decoded blocks must still be available at the memory position where they were decoded. + If it's not possible, save the relevant part of decoded data into a safe buffer, + and indicate where it stands using LZ4_setDictDecode() +*/ +int LZ4_decompress_safe_continue (void* LZ4_streamDecode, const char* source, char* dest, int compressedSize, int maxOutputSize); +int LZ4_decompress_fast_continue (void* LZ4_streamDecode, const char* source, char* dest, int originalSize); + +/* + * LZ4_setDictDecode + * Use this function to instruct where to find the dictionary. + * This function can be used to specify a static dictionary, + * or to instruct where to find some previously decoded data saved into a different memory space. + * Setting a size of 0 is allowed (same effect as no dictionary). + * Return : 1 if OK, 0 if error + */ +int LZ4_setDictDecode (void* LZ4_streamDecode, const char* dictionary, int dictSize); + + +/* +Advanced decoding functions : +*_usingDict() : + These decoding functions work the same as + a combination of LZ4_setDictDecode() followed by LZ4_decompress_x_continue() + all together into a single function call. + It doesn't use nor update an LZ4_streamDecode_t structure. +*/ +int LZ4_decompress_safe_usingDict (const char* source, char* dest, int compressedSize, int maxOutputSize, const char* dictStart, int dictSize); +int LZ4_decompress_fast_usingDict (const char* source, char* dest, int originalSize, const char* dictStart, int dictSize); + + + +#if defined (__cplusplus) +} +#endif diff --git a/mfbt/moz.build b/mfbt/moz.build new file mode 100644 index 000000000..f23a3b6f5 --- /dev/null +++ b/mfbt/moz.build @@ -0,0 +1,140 @@ +# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*- +# vim: set filetype=python: +# This Source Code Form is subject to the terms of the Mozilla Public +# License, v. 2.0. If a copy of the MPL was not distributed with this +# file, You can obtain one at http://mozilla.org/MPL/2.0/. + +TEST_DIRS += ['tests'] + +# On win we build two mfbt libs - mfbt linked to crt dlls here and in +# staticruntime we build a statically linked mfbt lib. +if CONFIG['OS_ARCH'] == 'WINNT': + DIRS += ['staticruntime'] + +Library('mfbt') + +EXPORTS.mozilla = [ + 'Alignment.h', + 'AllocPolicy.h', + 'AlreadyAddRefed.h', + 'Array.h', + 'ArrayUtils.h', + 'Assertions.h', + 'Atomics.h', + 'Attributes.h', + 'BinarySearch.h', + 'BloomFilter.h', + 'BufferList.h', + 'Casting.h', + 'ChaosMode.h', + 'Char16.h', + 'CheckedInt.h', + 'Compiler.h', + 'Compression.h', + 'DebugOnly.h', + 'decimal/Decimal.h', + 'double-conversion/double-conversion.h', + 'double-conversion/utils.h', + 'EndianUtils.h', + 'EnumeratedArray.h', + 'EnumeratedRange.h', + 'EnumSet.h', + 'EnumTypeTraits.h', + 'FastBernoulliTrial.h', + 'FloatingPoint.h', + 'Function.h', + 'GuardObjects.h', + 'HashFunctions.h', + 'IndexSequence.h', + 'IntegerPrintfMacros.h', + 'IntegerRange.h', + 'IntegerTypeTraits.h', + 'JSONWriter.h', + 'Likely.h', + 'LinkedList.h', + 'MacroArgs.h', + 'MacroForEach.h', + 'MathAlgorithms.h', + 'Maybe.h', + 'MaybeOneOf.h', + 'MemoryChecking.h', + 'MemoryReporting.h', + 'Move.h', + 'NotNull.h', + 'NullPtr.h', + 'Opaque.h', + 'OperatorNewExtensions.h', + 'Pair.h', + 'PodOperations.h', + 'Poison.h', + 'Range.h', + 'RangedArray.h', + 'RangedPtr.h', + 'ReentrancyGuard.h', + 'RefCounted.h', + 'RefCountType.h', + 'RefPtr.h', + 'ReverseIterator.h', + 'RollingMean.h', + 'Saturate.h', + 'Scoped.h', + 'ScopeExit.h', + 'SegmentedVector.h', + 'SHA1.h', + 'SizePrintfMacros.h', + 'SplayTree.h', + 'Sprintf.h', + 'StaticAnalysisFunctions.h', + 'TaggedAnonymousMemory.h', + 'TemplateLib.h', + 'ThreadLocal.h', + 'ToString.h', + 'Tuple.h', + 'TypedEnumBits.h', + 'Types.h', + 'TypeTraits.h', + 'UniquePtr.h', + 'UniquePtrExtensions.h', + 'Unused.h', + 'Variant.h', + 'Vector.h', + 'WeakPtr.h', + 'XorShift128PlusRNG.h', +] + +if CONFIG['OS_ARCH'] == 'WINNT': + EXPORTS.mozilla += [ + 'WindowsVersion.h', + ] +elif CONFIG['OS_ARCH'] == 'Linux': + EXPORTS.mozilla += [ + 'LinuxSignal.h', + ] + +include('objs.mozbuild') + +UNIFIED_SOURCES += mfbt_src_cppsrcs + +DEFINES['IMPL_MFBT'] = True + +SOURCES += mfbt_nonunified_src_cppsrcs + +DISABLE_STL_WRAPPING = True + +# Suppress warnings in third-party LZ4 code. +# TODO: Remove these suppressions after bug 993267 is fixed. + +if CONFIG['GNU_CXX']: + SOURCES['/mfbt/Compression.cpp'].flags += ['-Wno-unused-function'] + CXXFLAGS += ['-Wno-error=shadow'] + +if CONFIG['CLANG_CXX']: + # Suppress warnings from third-party V8 Decimal code. + SOURCES['/mfbt/decimal/Decimal.cpp'].flags += ['-Wno-implicit-fallthrough'] + +if CONFIG['_MSC_VER']: + # Error 4804 is "'>' : unsafe use of type 'bool' in operation" + SOURCES['/mfbt/Compression.cpp'].flags += ['-wd4804'] + +if CONFIG['MOZ_NEEDS_LIBATOMIC']: + OS_LIBS += ['atomic'] diff --git a/mfbt/objs.mozbuild b/mfbt/objs.mozbuild new file mode 100644 index 000000000..37b2240c4 --- /dev/null +++ b/mfbt/objs.mozbuild @@ -0,0 +1,40 @@ +# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*- +# vim: set filetype=python: +# This Source Code Form is subject to the terms of the Mozilla Public +# License, v. 2.0. If a copy of the MPL was not distributed with this +# file, You can obtain one at http://mozilla.org/MPL/2.0/. + +mfbt_src_lcppsrcs = [ + 'Assertions.cpp', + 'ChaosMode.cpp', + 'double-conversion/bignum-dtoa.cc', + 'double-conversion/bignum.cc', + 'double-conversion/cached-powers.cc', + 'double-conversion/diy-fp.cc', + 'double-conversion/double-conversion.cc', + 'double-conversion/fast-dtoa.cc', + 'double-conversion/fixed-dtoa.cc', + 'double-conversion/strtod.cc', + 'FloatingPoint.cpp', + 'HashFunctions.cpp', + 'JSONWriter.cpp', + 'Poison.cpp', + 'SHA1.cpp', + 'TaggedAnonymousMemory.cpp', + 'Unused.cpp', +] + +mfbt_src_cppsrcs = [ + '/mfbt/%s' % s for s in mfbt_src_lcppsrcs +] + +# Compression.cpp cannot be built in unified mode because it pulls in Windows system headers. +# Decimal.cpp doesn't build in unified mode with gcc. +mfbt_nonunified_src_lcppsrcs = [ + 'Compression.cpp', + 'decimal/Decimal.cpp', +] + +mfbt_nonunified_src_cppsrcs = [ + '/mfbt/%s' % s for s in mfbt_nonunified_src_lcppsrcs +] diff --git a/mfbt/staticruntime/moz.build b/mfbt/staticruntime/moz.build new file mode 100644 index 000000000..7fbbd2ea4 --- /dev/null +++ b/mfbt/staticruntime/moz.build @@ -0,0 +1,29 @@ +# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*- +# vim: set filetype=python: +# This Source Code Form is subject to the terms of the Mozilla Public +# License, v. 2.0. If a copy of the MPL was not distributed with this +# file, You can obtain one at http://mozilla.org/MPL/2.0/. + +Library('mfbt_staticruntime') + +include('../objs.mozbuild') + +UNIFIED_SOURCES += mfbt_src_cppsrcs + +DEFINES['IMPL_MFBT'] = True + +SOURCES += mfbt_nonunified_src_cppsrcs + +USE_STATIC_LIBS = True + +DISABLE_STL_WRAPPING = True + +# Suppress warnings in third-party LZ4 code. +# TODO: Remove these suppressions after bug 993267 is fixed. + +if CONFIG['GNU_CXX']: + SOURCES['/mfbt/Compression.cpp'].flags += ['-Wno-unused-function'] + +if CONFIG['_MSC_VER']: + # Error 4804 is "'>' : unsafe use of type 'bool' in operation" + SOURCES['/mfbt/Compression.cpp'].flags += ['-wd4804'] diff --git a/mfbt/tests/TestArray.cpp b/mfbt/tests/TestArray.cpp new file mode 100644 index 000000000..bdaeed825 --- /dev/null +++ b/mfbt/tests/TestArray.cpp @@ -0,0 +1,34 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Array.h" + +void TestInitialValueByConstructor() +{ + using namespace mozilla; + // Style 1 + Array<int32_t, 3> arr1(1, 2, 3); + MOZ_RELEASE_ASSERT(arr1[0] == 1); + MOZ_RELEASE_ASSERT(arr1[1] == 2); + MOZ_RELEASE_ASSERT(arr1[2] == 3); + // Style 2 + Array<int32_t, 3> arr2{5, 6, 7}; + MOZ_RELEASE_ASSERT(arr2[0] == 5); + MOZ_RELEASE_ASSERT(arr2[1] == 6); + MOZ_RELEASE_ASSERT(arr2[2] == 7); + // Style 3 + Array<int32_t, 3> arr3({8, 9, 10}); + MOZ_RELEASE_ASSERT(arr3[0] == 8); + MOZ_RELEASE_ASSERT(arr3[1] == 9); + MOZ_RELEASE_ASSERT(arr3[2] == 10); +} + +int +main() +{ + TestInitialValueByConstructor(); + return 0; +}
\ No newline at end of file diff --git a/mfbt/tests/TestArrayUtils.cpp b/mfbt/tests/TestArrayUtils.cpp new file mode 100644 index 000000000..6566a3cd8 --- /dev/null +++ b/mfbt/tests/TestArrayUtils.cpp @@ -0,0 +1,313 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/ArrayUtils.h" +#include "mozilla/Assertions.h" + +using mozilla::IsInRange; + +static void +TestIsInRangeNonClass() +{ + void* nul = nullptr; + int* intBegin = nullptr; + int* intEnd = intBegin + 1; + int* intEnd2 = intBegin + 2; + + MOZ_RELEASE_ASSERT(IsInRange(nul, intBegin, intEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(nul, intEnd, intEnd2)); + + MOZ_RELEASE_ASSERT(IsInRange(intBegin, intBegin, intEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(intEnd, intBegin, intEnd)); + + MOZ_RELEASE_ASSERT(IsInRange(intBegin, intBegin, intEnd2)); + MOZ_RELEASE_ASSERT(IsInRange(intEnd, intBegin, intEnd2)); + MOZ_RELEASE_ASSERT(!IsInRange(intEnd2, intBegin, intEnd2)); + + uintptr_t uintBegin = uintptr_t(intBegin); + uintptr_t uintEnd = uintptr_t(intEnd); + uintptr_t uintEnd2 = uintptr_t(intEnd2); + + MOZ_RELEASE_ASSERT(IsInRange(nul, uintBegin, uintEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(nul, uintEnd, uintEnd2)); + + MOZ_RELEASE_ASSERT(IsInRange(intBegin, uintBegin, uintEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(intEnd, uintBegin, uintEnd)); + + MOZ_RELEASE_ASSERT(IsInRange(intBegin, uintBegin, uintEnd2)); + MOZ_RELEASE_ASSERT(IsInRange(intEnd, uintBegin, uintEnd2)); + MOZ_RELEASE_ASSERT(!IsInRange(intEnd2, uintBegin, uintEnd2)); +} + +static void +TestIsInRangeVoid() +{ + int* intBegin = nullptr; + int* intEnd = intBegin + 1; + int* intEnd2 = intBegin + 2; + + void* voidBegin = intBegin; + void* voidEnd = intEnd; + void* voidEnd2 = intEnd2; + + MOZ_RELEASE_ASSERT(IsInRange(voidBegin, intBegin, intEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(voidEnd, intBegin, intEnd)); + + MOZ_RELEASE_ASSERT(IsInRange(voidBegin, voidBegin, voidEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(voidEnd, voidBegin, voidEnd)); + + MOZ_RELEASE_ASSERT(IsInRange(voidBegin, intBegin, intEnd2)); + MOZ_RELEASE_ASSERT(IsInRange(voidEnd, intBegin, intEnd2)); + MOZ_RELEASE_ASSERT(!IsInRange(voidEnd2, intBegin, intEnd2)); + + MOZ_RELEASE_ASSERT(IsInRange(voidBegin, voidBegin, voidEnd2)); + MOZ_RELEASE_ASSERT(IsInRange(voidEnd, voidBegin, voidEnd2)); + MOZ_RELEASE_ASSERT(!IsInRange(voidEnd2, voidBegin, voidEnd2)); + + uintptr_t uintBegin = uintptr_t(intBegin); + uintptr_t uintEnd = uintptr_t(intEnd); + uintptr_t uintEnd2 = uintptr_t(intEnd2); + + MOZ_RELEASE_ASSERT(IsInRange(voidBegin, uintBegin, uintEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(voidEnd, uintBegin, uintEnd)); + + MOZ_RELEASE_ASSERT(IsInRange(voidBegin, uintBegin, uintEnd2)); + MOZ_RELEASE_ASSERT(IsInRange(voidEnd, uintBegin, uintEnd2)); + MOZ_RELEASE_ASSERT(!IsInRange(voidEnd2, uintBegin, uintEnd2)); +} + +struct Base { int mX; }; + +static void +TestIsInRangeClass() +{ + void* nul = nullptr; + Base* baseBegin = nullptr; + Base* baseEnd = baseBegin + 1; + Base* baseEnd2 = baseBegin + 2; + + MOZ_RELEASE_ASSERT(IsInRange(nul, baseBegin, baseEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(nul, baseEnd, baseEnd2)); + + MOZ_RELEASE_ASSERT(IsInRange(baseBegin, baseBegin, baseEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(baseEnd, baseBegin, baseEnd)); + + MOZ_RELEASE_ASSERT(IsInRange(baseBegin, baseBegin, baseEnd2)); + MOZ_RELEASE_ASSERT(IsInRange(baseEnd, baseBegin, baseEnd2)); + MOZ_RELEASE_ASSERT(!IsInRange(baseEnd2, baseBegin, baseEnd2)); + + uintptr_t ubaseBegin = uintptr_t(baseBegin); + uintptr_t ubaseEnd = uintptr_t(baseEnd); + uintptr_t ubaseEnd2 = uintptr_t(baseEnd2); + + MOZ_RELEASE_ASSERT(IsInRange(nul, ubaseBegin, ubaseEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(nul, ubaseEnd, ubaseEnd2)); + + MOZ_RELEASE_ASSERT(IsInRange(baseBegin, ubaseBegin, ubaseEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(baseEnd, ubaseBegin, ubaseEnd)); + + MOZ_RELEASE_ASSERT(IsInRange(baseBegin, ubaseBegin, ubaseEnd2)); + MOZ_RELEASE_ASSERT(IsInRange(baseEnd, ubaseBegin, ubaseEnd2)); + MOZ_RELEASE_ASSERT(!IsInRange(baseEnd2, ubaseBegin, ubaseEnd2)); +} + +struct EmptyBase {}; + +static void +TestIsInRangeEmptyClass() +{ + void* nul = nullptr; + EmptyBase* baseBegin = nullptr; + EmptyBase* baseEnd = baseBegin + 1; + EmptyBase* baseEnd2 = baseBegin + 2; + + MOZ_RELEASE_ASSERT(IsInRange(nul, baseBegin, baseEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(nul, baseEnd, baseEnd2)); + + MOZ_RELEASE_ASSERT(IsInRange(baseBegin, baseBegin, baseEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(baseEnd, baseBegin, baseEnd)); + + MOZ_RELEASE_ASSERT(IsInRange(baseBegin, baseBegin, baseEnd2)); + MOZ_RELEASE_ASSERT(IsInRange(baseEnd, baseBegin, baseEnd2)); + MOZ_RELEASE_ASSERT(!IsInRange(baseEnd2, baseBegin, baseEnd2)); + + uintptr_t ubaseBegin = uintptr_t(baseBegin); + uintptr_t ubaseEnd = uintptr_t(baseEnd); + uintptr_t ubaseEnd2 = uintptr_t(baseEnd2); + + MOZ_RELEASE_ASSERT(IsInRange(nul, ubaseBegin, ubaseEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(nul, ubaseEnd, ubaseEnd2)); + + MOZ_RELEASE_ASSERT(IsInRange(baseBegin, ubaseBegin, ubaseEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(baseEnd, ubaseBegin, ubaseEnd)); + + MOZ_RELEASE_ASSERT(IsInRange(baseBegin, ubaseBegin, ubaseEnd2)); + MOZ_RELEASE_ASSERT(IsInRange(baseEnd, ubaseBegin, ubaseEnd2)); + MOZ_RELEASE_ASSERT(!IsInRange(baseEnd2, ubaseBegin, ubaseEnd2)); +} + +struct Derived : Base {}; + +static void +TestIsInRangeClassDerived() +{ + void* nul = nullptr; + Derived* derivedBegin = nullptr; + Derived* derivedEnd = derivedBegin + 1; + Derived* derivedEnd2 = derivedBegin + 2; + + Base* baseBegin = static_cast<Base*>(derivedBegin); + Base* baseEnd = static_cast<Base*>(derivedEnd); + Base* baseEnd2 = static_cast<Base*>(derivedEnd2); + + MOZ_RELEASE_ASSERT(IsInRange(nul, derivedBegin, derivedEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(nul, derivedEnd, derivedEnd2)); + + MOZ_RELEASE_ASSERT(IsInRange(baseBegin, derivedBegin, derivedEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(baseEnd, derivedBegin, derivedEnd)); + + MOZ_RELEASE_ASSERT(IsInRange(baseBegin, derivedBegin, derivedEnd2)); + MOZ_RELEASE_ASSERT(IsInRange(baseEnd, derivedBegin, derivedEnd2)); + MOZ_RELEASE_ASSERT(!IsInRange(baseEnd2, derivedBegin, derivedEnd2)); + + uintptr_t uderivedBegin = uintptr_t(derivedBegin); + uintptr_t uderivedEnd = uintptr_t(derivedEnd); + uintptr_t uderivedEnd2 = uintptr_t(derivedEnd2); + + MOZ_RELEASE_ASSERT(IsInRange(derivedBegin, uderivedBegin, uderivedEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(derivedEnd, uderivedBegin, uderivedEnd)); + + MOZ_RELEASE_ASSERT(IsInRange(derivedBegin, uderivedBegin, uderivedEnd2)); + MOZ_RELEASE_ASSERT(IsInRange(derivedEnd, uderivedBegin, uderivedEnd2)); + MOZ_RELEASE_ASSERT(!IsInRange(derivedEnd2, uderivedBegin, uderivedEnd2)); +} + +struct DerivedEmpty : EmptyBase {}; + +static void +TestIsInRangeClassDerivedEmpty() +{ + void* nul = nullptr; + DerivedEmpty* derivedEmptyBegin = nullptr; + DerivedEmpty* derivedEmptyEnd = derivedEmptyBegin + 1; + DerivedEmpty* derivedEmptyEnd2 = derivedEmptyBegin + 2; + + EmptyBase* baseBegin = static_cast<EmptyBase*>(derivedEmptyBegin); + EmptyBase* baseEnd = static_cast<EmptyBase*>(derivedEmptyEnd); + EmptyBase* baseEnd2 = static_cast<EmptyBase*>(derivedEmptyEnd2); + + MOZ_RELEASE_ASSERT(IsInRange(nul, derivedEmptyBegin, derivedEmptyEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(nul, derivedEmptyEnd, derivedEmptyEnd2)); + + MOZ_RELEASE_ASSERT(IsInRange(baseBegin, derivedEmptyBegin, derivedEmptyEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(baseEnd, derivedEmptyBegin, derivedEmptyEnd)); + + MOZ_RELEASE_ASSERT(IsInRange(baseBegin, derivedEmptyBegin, derivedEmptyEnd2)); + MOZ_RELEASE_ASSERT(IsInRange(baseEnd, derivedEmptyBegin, derivedEmptyEnd2)); + MOZ_RELEASE_ASSERT(!IsInRange(baseEnd2, derivedEmptyBegin, derivedEmptyEnd2)); + + uintptr_t uderivedEmptyBegin = uintptr_t(derivedEmptyBegin); + uintptr_t uderivedEmptyEnd = uintptr_t(derivedEmptyEnd); + uintptr_t uderivedEmptyEnd2 = uintptr_t(derivedEmptyEnd2); + + MOZ_RELEASE_ASSERT(IsInRange(derivedEmptyBegin, uderivedEmptyBegin, + uderivedEmptyEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(derivedEmptyEnd, uderivedEmptyBegin, + uderivedEmptyEnd)); + + MOZ_RELEASE_ASSERT(IsInRange(derivedEmptyBegin, uderivedEmptyBegin, + uderivedEmptyEnd2)); + MOZ_RELEASE_ASSERT(IsInRange(derivedEmptyEnd, uderivedEmptyBegin, + uderivedEmptyEnd2)); + MOZ_RELEASE_ASSERT(!IsInRange(derivedEmptyEnd2, uderivedEmptyBegin, + uderivedEmptyEnd2)); +} + +struct ExtraDerived : Base { int y; }; + +static void +TestIsInRangeClassExtraDerived() +{ + void* nul = nullptr; + ExtraDerived* derivedBegin = nullptr; + ExtraDerived* derivedEnd = derivedBegin + 1; + ExtraDerived* derivedEnd2 = derivedBegin + 2; + + Base* baseBegin = static_cast<Base*>(derivedBegin); + Base* baseEnd = static_cast<Base*>(derivedEnd); + Base* baseEnd2 = static_cast<Base*>(derivedEnd2); + + MOZ_RELEASE_ASSERT(IsInRange(nul, derivedBegin, derivedEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(nul, derivedEnd, derivedEnd2)); + + MOZ_RELEASE_ASSERT(IsInRange(baseBegin, derivedBegin, derivedEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(baseEnd, derivedBegin, derivedEnd)); + + MOZ_RELEASE_ASSERT(IsInRange(baseBegin, derivedBegin, derivedEnd2)); + MOZ_RELEASE_ASSERT(IsInRange(baseEnd, derivedBegin, derivedEnd2)); + MOZ_RELEASE_ASSERT(!IsInRange(baseEnd2, derivedBegin, derivedEnd2)); + + uintptr_t uderivedBegin = uintptr_t(derivedBegin); + uintptr_t uderivedEnd = uintptr_t(derivedEnd); + uintptr_t uderivedEnd2 = uintptr_t(derivedEnd2); + + MOZ_RELEASE_ASSERT(IsInRange(derivedBegin, uderivedBegin, uderivedEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(derivedEnd, uderivedBegin, uderivedEnd)); + + MOZ_RELEASE_ASSERT(IsInRange(derivedBegin, uderivedBegin, uderivedEnd2)); + MOZ_RELEASE_ASSERT(IsInRange(derivedEnd, uderivedBegin, uderivedEnd2)); + MOZ_RELEASE_ASSERT(!IsInRange(derivedEnd2, uderivedBegin, uderivedEnd2)); +} + +struct ExtraDerivedEmpty : EmptyBase { int y; }; + +static void +TestIsInRangeClassExtraDerivedEmpty() +{ + void* nul = nullptr; + ExtraDerivedEmpty* derivedBegin = nullptr; + ExtraDerivedEmpty* derivedEnd = derivedBegin + 1; + ExtraDerivedEmpty* derivedEnd2 = derivedBegin + 2; + + EmptyBase* baseBegin = static_cast<EmptyBase*>(derivedBegin); + EmptyBase* baseEnd = static_cast<EmptyBase*>(derivedEnd); + EmptyBase* baseEnd2 = static_cast<EmptyBase*>(derivedEnd2); + + MOZ_RELEASE_ASSERT(IsInRange(nul, derivedBegin, derivedEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(nul, derivedEnd, derivedEnd2)); + + MOZ_RELEASE_ASSERT(IsInRange(baseBegin, derivedBegin, derivedEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(baseEnd, derivedBegin, derivedEnd)); + + MOZ_RELEASE_ASSERT(IsInRange(baseBegin, derivedBegin, derivedEnd2)); + MOZ_RELEASE_ASSERT(IsInRange(baseEnd, derivedBegin, derivedEnd2)); + MOZ_RELEASE_ASSERT(!IsInRange(baseEnd2, derivedBegin, derivedEnd2)); + + uintptr_t uderivedBegin = uintptr_t(derivedBegin); + uintptr_t uderivedEnd = uintptr_t(derivedEnd); + uintptr_t uderivedEnd2 = uintptr_t(derivedEnd2); + + MOZ_RELEASE_ASSERT(IsInRange(derivedBegin, uderivedBegin, uderivedEnd)); + MOZ_RELEASE_ASSERT(!IsInRange(derivedEnd, uderivedBegin, uderivedEnd)); + + MOZ_RELEASE_ASSERT(IsInRange(derivedBegin, uderivedBegin, uderivedEnd2)); + MOZ_RELEASE_ASSERT(IsInRange(derivedEnd, uderivedBegin, uderivedEnd2)); + MOZ_RELEASE_ASSERT(!IsInRange(derivedEnd2, uderivedBegin, uderivedEnd2)); +} + +int +main() +{ + TestIsInRangeNonClass(); + TestIsInRangeVoid(); + TestIsInRangeClass(); + TestIsInRangeEmptyClass(); + TestIsInRangeClassDerived(); + TestIsInRangeClassDerivedEmpty(); + TestIsInRangeClassExtraDerived(); + TestIsInRangeClassExtraDerivedEmpty(); + return 0; +} diff --git a/mfbt/tests/TestAtomics.cpp b/mfbt/tests/TestAtomics.cpp new file mode 100644 index 000000000..e23b3d517 --- /dev/null +++ b/mfbt/tests/TestAtomics.cpp @@ -0,0 +1,295 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/Atomics.h" + +#include <stdint.h> + +using mozilla::Atomic; +using mozilla::MemoryOrdering; +using mozilla::Relaxed; +using mozilla::ReleaseAcquire; +using mozilla::SequentiallyConsistent; + +#define A(a,b) MOZ_RELEASE_ASSERT(a,b) + +template <typename T, MemoryOrdering Order> +static void +TestTypeWithOrdering() +{ + Atomic<T, Order> atomic(5); + A(atomic == 5, "Atomic variable did not initialize"); + + // Test atomic increment + A(++atomic == T(6), "Atomic increment did not work"); + A(atomic++ == T(6), "Atomic post-increment did not work"); + A(atomic == T(7), "Atomic post-increment did not work"); + + // Test atomic decrement + A(--atomic == 6, "Atomic decrement did not work"); + A(atomic-- == 6, "Atomic post-decrement did not work"); + A(atomic == 5, "Atomic post-decrement did not work"); + + // Test other arithmetic. + T result; + result = (atomic += T(5)); + A(atomic == T(10), "Atomic += did not work"); + A(result == T(10), "Atomic += returned the wrong value"); + result = (atomic -= T(3)); + A(atomic == T(7), "Atomic -= did not work"); + A(result == T(7), "Atomic -= returned the wrong value"); + + // Test assignment + result = (atomic = T(5)); + A(atomic == T(5), "Atomic assignment failed"); + A(result == T(5), "Atomic assignment returned the wrong value"); + + // Test logical operations. + result = (atomic ^= T(2)); + A(atomic == T(7), "Atomic ^= did not work"); + A(result == T(7), "Atomic ^= returned the wrong value"); + result = (atomic ^= T(4)); + A(atomic == T(3), "Atomic ^= did not work"); + A(result == T(3), "Atomic ^= returned the wrong value"); + result = (atomic |= T(8)); + A(atomic == T(11), "Atomic |= did not work"); + A(result == T(11), "Atomic |= returned the wrong value"); + result = (atomic |= T(8)); + A(atomic == T(11), "Atomic |= did not work"); + A(result == T(11), "Atomic |= returned the wrong value"); + result = (atomic &= T(12)); + A(atomic == T(8), "Atomic &= did not work"); + A(result == T(8), "Atomic &= returned the wrong value"); + + // Test exchange. + atomic = T(30); + result = atomic.exchange(42); + A(atomic == T(42), "Atomic exchange did not work"); + A(result == T(30), "Atomic exchange returned the wrong value"); + + // Test CAS. + atomic = T(1); + bool boolResult = atomic.compareExchange(0, 2); + A(!boolResult, "CAS should have returned false."); + A(atomic == T(1), "CAS shouldn't have done anything."); + + boolResult = atomic.compareExchange(1, 42); + A(boolResult, "CAS should have succeeded."); + A(atomic == T(42), "CAS should have changed atomic's value."); +} + +template<typename T, MemoryOrdering Order> +static void +TestPointerWithOrdering() +{ + T array1[10]; + Atomic<T*, Order> atomic(array1); + A(atomic == array1, "Atomic variable did not initialize"); + + // Test atomic increment + A(++atomic == array1 + 1, "Atomic increment did not work"); + A(atomic++ == array1 + 1, "Atomic post-increment did not work"); + A(atomic == array1 + 2, "Atomic post-increment did not work"); + + // Test atomic decrement + A(--atomic == array1 + 1, "Atomic decrement did not work"); + A(atomic-- == array1 + 1, "Atomic post-decrement did not work"); + A(atomic == array1, "Atomic post-decrement did not work"); + + // Test other arithmetic operations + T* result; + result = (atomic += 2); + A(atomic == array1 + 2, "Atomic += did not work"); + A(result == array1 + 2, "Atomic += returned the wrong value"); + result = (atomic -= 1); + A(atomic == array1 + 1, "Atomic -= did not work"); + A(result == array1 + 1, "Atomic -= returned the wrong value"); + + // Test stores + result = (atomic = array1); + A(atomic == array1, "Atomic assignment did not work"); + A(result == array1, "Atomic assignment returned the wrong value"); + + // Test exchange + atomic = array1 + 2; + result = atomic.exchange(array1); + A(atomic == array1, "Atomic exchange did not work"); + A(result == array1 + 2, "Atomic exchange returned the wrong value"); + + atomic = array1; + bool boolResult = atomic.compareExchange(array1 + 1, array1 + 2); + A(!boolResult, "CAS should have returned false."); + A(atomic == array1, "CAS shouldn't have done anything."); + + boolResult = atomic.compareExchange(array1, array1 + 3); + A(boolResult, "CAS should have succeeded."); + A(atomic == array1 + 3, "CAS should have changed atomic's value."); +} + +enum EnumType +{ + EnumType_0 = 0, + EnumType_1 = 1, + EnumType_2 = 2, + EnumType_3 = 3 +}; + +template<MemoryOrdering Order> +static void +TestEnumWithOrdering() +{ + Atomic<EnumType, Order> atomic(EnumType_2); + A(atomic == EnumType_2, "Atomic variable did not initialize"); + + // Test assignment + EnumType result; + result = (atomic = EnumType_3); + A(atomic == EnumType_3, "Atomic assignment failed"); + A(result == EnumType_3, "Atomic assignment returned the wrong value"); + + // Test exchange. + atomic = EnumType_1; + result = atomic.exchange(EnumType_2); + A(atomic == EnumType_2, "Atomic exchange did not work"); + A(result == EnumType_1, "Atomic exchange returned the wrong value"); + + // Test CAS. + atomic = EnumType_1; + bool boolResult = atomic.compareExchange(EnumType_0, EnumType_2); + A(!boolResult, "CAS should have returned false."); + A(atomic == EnumType_1, "CAS shouldn't have done anything."); + + boolResult = atomic.compareExchange(EnumType_1, EnumType_3); + A(boolResult, "CAS should have succeeded."); + A(atomic == EnumType_3, "CAS should have changed atomic's value."); +} + +enum class EnumClass : uint32_t +{ + Value0 = 0, + Value1 = 1, + Value2 = 2, + Value3 = 3 +}; + +template<MemoryOrdering Order> +static void +TestEnumClassWithOrdering() +{ + Atomic<EnumClass, Order> atomic(EnumClass::Value2); + A(atomic == EnumClass::Value2, "Atomic variable did not initialize"); + + // Test assignment + EnumClass result; + result = (atomic = EnumClass::Value3); + A(atomic == EnumClass::Value3, "Atomic assignment failed"); + A(result == EnumClass::Value3, "Atomic assignment returned the wrong value"); + + // Test exchange. + atomic = EnumClass::Value1; + result = atomic.exchange(EnumClass::Value2); + A(atomic == EnumClass::Value2, "Atomic exchange did not work"); + A(result == EnumClass::Value1, "Atomic exchange returned the wrong value"); + + // Test CAS. + atomic = EnumClass::Value1; + bool boolResult = atomic.compareExchange(EnumClass::Value0, EnumClass::Value2); + A(!boolResult, "CAS should have returned false."); + A(atomic == EnumClass::Value1, "CAS shouldn't have done anything."); + + boolResult = atomic.compareExchange(EnumClass::Value1, EnumClass::Value3); + A(boolResult, "CAS should have succeeded."); + A(atomic == EnumClass::Value3, "CAS should have changed atomic's value."); +} + +template <MemoryOrdering Order> +static void +TestBoolWithOrdering() +{ + Atomic<bool, Order> atomic(false); + A(atomic == false, "Atomic variable did not initialize"); + + // Test assignment + bool result; + result = (atomic = true); + A(atomic == true, "Atomic assignment failed"); + A(result == true, "Atomic assignment returned the wrong value"); + + // Test exchange. + atomic = false; + result = atomic.exchange(true); + A(atomic == true, "Atomic exchange did not work"); + A(result == false, "Atomic exchange returned the wrong value"); + + // Test CAS. + atomic = false; + bool boolResult = atomic.compareExchange(true, false); + A(!boolResult, "CAS should have returned false."); + A(atomic == false, "CAS shouldn't have done anything."); + + boolResult = atomic.compareExchange(false, true); + A(boolResult, "CAS should have succeeded."); + A(atomic == true, "CAS should have changed atomic's value."); +} + +template <typename T> +static void +TestType() +{ + TestTypeWithOrdering<T, SequentiallyConsistent>(); + TestTypeWithOrdering<T, ReleaseAcquire>(); + TestTypeWithOrdering<T, Relaxed>(); +} + +template<typename T> +static void +TestPointer() +{ + TestPointerWithOrdering<T, SequentiallyConsistent>(); + TestPointerWithOrdering<T, ReleaseAcquire>(); + TestPointerWithOrdering<T, Relaxed>(); +} + +static void +TestEnum() +{ + TestEnumWithOrdering<SequentiallyConsistent>(); + TestEnumWithOrdering<ReleaseAcquire>(); + TestEnumWithOrdering<Relaxed>(); + + TestEnumClassWithOrdering<SequentiallyConsistent>(); + TestEnumClassWithOrdering<ReleaseAcquire>(); + TestEnumClassWithOrdering<Relaxed>(); +} + +static void +TestBool() +{ + TestBoolWithOrdering<SequentiallyConsistent>(); + TestBoolWithOrdering<ReleaseAcquire>(); + TestBoolWithOrdering<Relaxed>(); +} + +#undef A + +int +main() +{ + TestType<uint32_t>(); + TestType<int32_t>(); + TestType<uint64_t>(); + TestType<int64_t>(); + TestType<intptr_t>(); + TestType<uintptr_t>(); + TestPointer<int>(); + TestPointer<float>(); + TestPointer<uint16_t*>(); + TestPointer<uint32_t*>(); + TestEnum(); + TestBool(); + return 0; +} diff --git a/mfbt/tests/TestBinarySearch.cpp b/mfbt/tests/TestBinarySearch.cpp new file mode 100644 index 000000000..44644bd3a --- /dev/null +++ b/mfbt/tests/TestBinarySearch.cpp @@ -0,0 +1,113 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/BinarySearch.h" +#include "mozilla/Vector.h" + +using mozilla::ArrayLength; +using mozilla::BinarySearch; +using mozilla::BinarySearchIf; +using mozilla::Vector; + +#define A(a) MOZ_RELEASE_ASSERT(a) + +struct Person +{ + int mAge; + int mId; + Person(int aAge, int aId) : mAge(aAge), mId(aId) {} +}; + +struct GetAge +{ + Vector<Person>& mV; + explicit GetAge(Vector<Person>& aV) : mV(aV) {} + int operator[](size_t index) const { return mV[index].mAge; } +}; + +struct RangeFinder { + const int mLower, mUpper; + RangeFinder(int lower, int upper) : mLower(lower), mUpper(upper) {} + int operator()(int val) const { + if (val >= mUpper) return -1; + if (val < mLower) return 1; + return 0; + } +}; + +static void +TestBinarySearch() +{ + size_t m; + + Vector<int> v1; + MOZ_RELEASE_ASSERT(v1.append(2)); + MOZ_RELEASE_ASSERT(v1.append(4)); + MOZ_RELEASE_ASSERT(v1.append(6)); + MOZ_RELEASE_ASSERT(v1.append(8)); + + MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, v1.length(), 1, &m) && m == 0); + MOZ_RELEASE_ASSERT( BinarySearch(v1, 0, v1.length(), 2, &m) && m == 0); + MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, v1.length(), 3, &m) && m == 1); + MOZ_RELEASE_ASSERT( BinarySearch(v1, 0, v1.length(), 4, &m) && m == 1); + MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, v1.length(), 5, &m) && m == 2); + MOZ_RELEASE_ASSERT( BinarySearch(v1, 0, v1.length(), 6, &m) && m == 2); + MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, v1.length(), 7, &m) && m == 3); + MOZ_RELEASE_ASSERT( BinarySearch(v1, 0, v1.length(), 8, &m) && m == 3); + MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, v1.length(), 9, &m) && m == 4); + + MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 1, &m) && m == 1); + MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 2, &m) && m == 1); + MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 3, &m) && m == 1); + MOZ_RELEASE_ASSERT( BinarySearch(v1, 1, 3, 4, &m) && m == 1); + MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 5, &m) && m == 2); + MOZ_RELEASE_ASSERT( BinarySearch(v1, 1, 3, 6, &m) && m == 2); + MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 7, &m) && m == 3); + MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 8, &m) && m == 3); + MOZ_RELEASE_ASSERT(!BinarySearch(v1, 1, 3, 9, &m) && m == 3); + + MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, 0, 0, &m) && m == 0); + MOZ_RELEASE_ASSERT(!BinarySearch(v1, 0, 0, 9, &m) && m == 0); + + Vector<int> v2; + MOZ_RELEASE_ASSERT(!BinarySearch(v2, 0, 0, 0, &m) && m == 0); + MOZ_RELEASE_ASSERT(!BinarySearch(v2, 0, 0, 9, &m) && m == 0); + + Vector<Person> v3; + MOZ_RELEASE_ASSERT(v3.append(Person(2, 42))); + MOZ_RELEASE_ASSERT(v3.append(Person(4, 13))); + MOZ_RELEASE_ASSERT(v3.append(Person(6, 360))); + + A(!BinarySearch(GetAge(v3), 0, v3.length(), 1, &m) && m == 0); + A( BinarySearch(GetAge(v3), 0, v3.length(), 2, &m) && m == 0); + A(!BinarySearch(GetAge(v3), 0, v3.length(), 3, &m) && m == 1); + A( BinarySearch(GetAge(v3), 0, v3.length(), 4, &m) && m == 1); + A(!BinarySearch(GetAge(v3), 0, v3.length(), 5, &m) && m == 2); + A( BinarySearch(GetAge(v3), 0, v3.length(), 6, &m) && m == 2); + A(!BinarySearch(GetAge(v3), 0, v3.length(), 7, &m) && m == 3); +} + +static void +TestBinarySearchIf() +{ + const int v1[] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 }; + const size_t len = ArrayLength(v1); + size_t m; + + A( BinarySearchIf(v1, 0, len, RangeFinder( 2, 3), &m) && m == 2); + A(!BinarySearchIf(v1, 0, len, RangeFinder(-5, -2), &m) && m == 0); + A( BinarySearchIf(v1, 0, len, RangeFinder( 3, 5), &m) && m >= 3 && m < 5); + A(!BinarySearchIf(v1, 0, len, RangeFinder(10, 12), &m) && m == 10); +} + +int +main() +{ + TestBinarySearch(); + TestBinarySearchIf(); + return 0; +} diff --git a/mfbt/tests/TestBloomFilter.cpp b/mfbt/tests/TestBloomFilter.cpp new file mode 100644 index 000000000..42e8b821e --- /dev/null +++ b/mfbt/tests/TestBloomFilter.cpp @@ -0,0 +1,103 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/BloomFilter.h" + +#include <stddef.h> +#include <stdio.h> + +using mozilla::BloomFilter; + +class FilterChecker +{ +public: + explicit FilterChecker(uint32_t aHash) : mHash(aHash) { } + + uint32_t hash() const { return mHash; } + +private: + uint32_t mHash; +}; + +int +main() +{ + BloomFilter<12, FilterChecker>* filter = new BloomFilter<12, FilterChecker>(); + MOZ_RELEASE_ASSERT(filter); + + FilterChecker one(1); + FilterChecker two(0x20000); + FilterChecker many(0x10000); + FilterChecker multiple(0x20001); + + filter->add(&one); + MOZ_RELEASE_ASSERT(filter->mightContain(&one), + "Filter should contain 'one'"); + + MOZ_RELEASE_ASSERT(!filter->mightContain(&multiple), + "Filter claims to contain 'multiple' when it should not"); + + MOZ_RELEASE_ASSERT(filter->mightContain(&many), + "Filter should contain 'many' (false positive)"); + + filter->add(&two); + MOZ_RELEASE_ASSERT(filter->mightContain(&multiple), + "Filter should contain 'multiple' (false positive)"); + + // Test basic removals + filter->remove(&two); + MOZ_RELEASE_ASSERT(!filter->mightContain(&multiple), + "Filter claims to contain 'multiple' when it should not after two " + "was removed"); + + // Test multiple addition/removal + const size_t FILTER_SIZE = 255; + for (size_t i = 0; i < FILTER_SIZE - 1; ++i) { + filter->add(&two); + } + MOZ_RELEASE_ASSERT(filter->mightContain(&multiple), + "Filter should contain 'multiple' after 'two' added lots of times " + "(false positive)"); + + for (size_t i = 0; i < FILTER_SIZE - 1; ++i) { + filter->remove(&two); + } + MOZ_RELEASE_ASSERT(!filter->mightContain(&multiple), + "Filter claims to contain 'multiple' when it should not after two " + "was removed lots of times"); + + // Test overflowing the filter buckets + for (size_t i = 0; i < FILTER_SIZE + 1; ++i) { + filter->add(&two); + } + MOZ_RELEASE_ASSERT(filter->mightContain(&multiple), + "Filter should contain 'multiple' after 'two' added lots more " + "times (false positive)"); + + for (size_t i = 0; i < FILTER_SIZE + 1; ++i) { + filter->remove(&two); + } + MOZ_RELEASE_ASSERT(filter->mightContain(&multiple), + "Filter claims to not contain 'multiple' even though we should " + "have run out of space in the buckets (false positive)"); + MOZ_RELEASE_ASSERT(filter->mightContain(&two), + "Filter claims to not contain 'two' even though we should have " + "run out of space in the buckets (false positive)"); + + filter->remove(&one); + + MOZ_RELEASE_ASSERT(!filter->mightContain(&one), + "Filter should not contain 'one', because we didn't overflow its " + "bucket"); + + filter->clear(); + + MOZ_RELEASE_ASSERT(!filter->mightContain(&multiple), + "clear() failed to work"); + + return 0; +} diff --git a/mfbt/tests/TestBufferList.cpp b/mfbt/tests/TestBufferList.cpp new file mode 100644 index 000000000..cccaac021 --- /dev/null +++ b/mfbt/tests/TestBufferList.cpp @@ -0,0 +1,256 @@ +/* -*- Mode: C++; tab-width: 9; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +// This is included first to ensure it doesn't implicitly depend on anything +// else. +#include "mozilla/BufferList.h" + +// It would be nice if we could use the InfallibleAllocPolicy from mozalloc, +// but MFBT cannot use mozalloc. +class InfallibleAllocPolicy +{ +public: + template <typename T> + T* pod_malloc(size_t aNumElems) + { + if (aNumElems & mozilla::tl::MulOverflowMask<sizeof(T)>::value) { + MOZ_CRASH("TestBufferList.cpp: overflow"); + } + T* rv = static_cast<T*>(malloc(aNumElems * sizeof(T))); + if (!rv) { + MOZ_CRASH("TestBufferList.cpp: out of memory"); + } + return rv; + } + + void free_(void* aPtr) { free(aPtr); } + + void reportAllocOverflow() const {} + + bool checkSimulatedOOM() const { return true; } +}; + +typedef mozilla::BufferList<InfallibleAllocPolicy> BufferList; + +int main(void) +{ + const size_t kInitialSize = 16; + const size_t kInitialCapacity = 24; + const size_t kStandardCapacity = 32; + + BufferList bl(kInitialSize, kInitialCapacity, kStandardCapacity); + + memset(bl.Start(), 0x0c, kInitialSize); + MOZ_RELEASE_ASSERT(bl.Size() == kInitialSize); + + // Simple iteration and access. + + BufferList::IterImpl iter(bl.Iter()); + MOZ_RELEASE_ASSERT(iter.RemainingInSegment() == kInitialSize); + MOZ_RELEASE_ASSERT(iter.HasRoomFor(kInitialSize)); + MOZ_RELEASE_ASSERT(!iter.HasRoomFor(kInitialSize + 1)); + MOZ_RELEASE_ASSERT(!iter.HasRoomFor(size_t(-1))); + MOZ_RELEASE_ASSERT(*iter.Data() == 0x0c); + MOZ_RELEASE_ASSERT(!iter.Done()); + + iter.Advance(bl, 4); + MOZ_RELEASE_ASSERT(iter.RemainingInSegment() == kInitialSize - 4); + MOZ_RELEASE_ASSERT(iter.HasRoomFor(kInitialSize - 4)); + MOZ_RELEASE_ASSERT(*iter.Data() == 0x0c); + MOZ_RELEASE_ASSERT(!iter.Done()); + + iter.Advance(bl, 11); + MOZ_RELEASE_ASSERT(iter.RemainingInSegment() == kInitialSize - 4 - 11); + MOZ_RELEASE_ASSERT(iter.HasRoomFor(kInitialSize - 4 - 11)); + MOZ_RELEASE_ASSERT(!iter.HasRoomFor(kInitialSize - 4 - 11 + 1)); + MOZ_RELEASE_ASSERT(*iter.Data() == 0x0c); + MOZ_RELEASE_ASSERT(!iter.Done()); + + iter.Advance(bl, kInitialSize - 4 - 11); + MOZ_RELEASE_ASSERT(iter.RemainingInSegment() == 0); + MOZ_RELEASE_ASSERT(!iter.HasRoomFor(1)); + MOZ_RELEASE_ASSERT(iter.Done()); + + // Writing to the buffer. + + const size_t kSmallWrite = 16; + + char toWrite[kSmallWrite]; + memset(toWrite, 0x0a, kSmallWrite); + bl.WriteBytes(toWrite, kSmallWrite); + + MOZ_RELEASE_ASSERT(bl.Size() == kInitialSize + kSmallWrite); + + iter = bl.Iter(); + iter.Advance(bl, kInitialSize); + MOZ_RELEASE_ASSERT(!iter.Done()); + MOZ_RELEASE_ASSERT(iter.RemainingInSegment() == kInitialCapacity - kInitialSize); + MOZ_RELEASE_ASSERT(iter.HasRoomFor(kInitialCapacity - kInitialSize)); + MOZ_RELEASE_ASSERT(*iter.Data() == 0x0a); + + // AdvanceAcrossSegments. + + iter = bl.Iter(); + MOZ_RELEASE_ASSERT(iter.AdvanceAcrossSegments(bl, kInitialCapacity - 4)); + MOZ_RELEASE_ASSERT(!iter.Done()); + MOZ_RELEASE_ASSERT(iter.RemainingInSegment() == 4); + MOZ_RELEASE_ASSERT(iter.HasRoomFor(4)); + MOZ_RELEASE_ASSERT(*iter.Data() == 0x0a); + + iter = bl.Iter(); + MOZ_RELEASE_ASSERT(iter.AdvanceAcrossSegments(bl, kInitialSize + kSmallWrite - 4)); + MOZ_RELEASE_ASSERT(!iter.Done()); + MOZ_RELEASE_ASSERT(iter.RemainingInSegment() == 4); + MOZ_RELEASE_ASSERT(iter.HasRoomFor(4)); + MOZ_RELEASE_ASSERT(*iter.Data() == 0x0a); + + MOZ_RELEASE_ASSERT(bl.Iter().AdvanceAcrossSegments(bl, kInitialSize + kSmallWrite - 1)); + MOZ_RELEASE_ASSERT(bl.Iter().AdvanceAcrossSegments(bl, kInitialSize + kSmallWrite)); + MOZ_RELEASE_ASSERT(!bl.Iter().AdvanceAcrossSegments(bl, kInitialSize + kSmallWrite + 1)); + MOZ_RELEASE_ASSERT(!bl.Iter().AdvanceAcrossSegments(bl, size_t(-1))); + + // Reading non-contiguous bytes. + + char toRead[kSmallWrite]; + iter = bl.Iter(); + iter.Advance(bl, kInitialSize); + bl.ReadBytes(iter, toRead, kSmallWrite); + MOZ_RELEASE_ASSERT(memcmp(toRead, toWrite, kSmallWrite) == 0); + MOZ_RELEASE_ASSERT(iter.Done()); + + // Make sure reading up to the end of a segment advances the iter to the next + // segment. + iter = bl.Iter(); + bl.ReadBytes(iter, toRead, kInitialSize); + MOZ_RELEASE_ASSERT(!iter.Done()); + MOZ_RELEASE_ASSERT(iter.RemainingInSegment() == kInitialCapacity - kInitialSize); + + const size_t kBigWrite = 1024; + + char* toWriteBig = static_cast<char*>(malloc(kBigWrite)); + for (unsigned i = 0; i < kBigWrite; i++) { + toWriteBig[i] = i % 37; + } + bl.WriteBytes(toWriteBig, kBigWrite); + + char* toReadBig = static_cast<char*>(malloc(kBigWrite)); + iter = bl.Iter(); + MOZ_RELEASE_ASSERT(iter.AdvanceAcrossSegments(bl, kInitialSize + kSmallWrite)); + bl.ReadBytes(iter, toReadBig, kBigWrite); + MOZ_RELEASE_ASSERT(memcmp(toReadBig, toWriteBig, kBigWrite) == 0); + MOZ_RELEASE_ASSERT(iter.Done()); + + free(toReadBig); + free(toWriteBig); + + // Currently bl contains these segments: + // #0: offset 0, [0x0c]*16 + [0x0a]*8, size 24 + // #1: offset 24, [0x0a]*8 + [i%37 for i in 0..24], size 32 + // #2: offset 56, [i%37 for i in 24..56, size 32 + // ... + // #32: offset 1016, [i%37 for i in 984..1016], size 32 + // #33: offset 1048, [i%37 for i in 1016..1024], size 8 + + static size_t kTotalSize = kInitialSize + kSmallWrite + kBigWrite; + + MOZ_RELEASE_ASSERT(bl.Size() == kTotalSize); + + static size_t kLastSegmentSize = (kTotalSize - kInitialCapacity) % kStandardCapacity; + + iter = bl.Iter(); + MOZ_RELEASE_ASSERT(iter.AdvanceAcrossSegments(bl, kTotalSize - kLastSegmentSize - kStandardCapacity)); + MOZ_RELEASE_ASSERT(iter.RemainingInSegment() == kStandardCapacity); + iter.Advance(bl, kStandardCapacity); + MOZ_RELEASE_ASSERT(iter.RemainingInSegment() == kLastSegmentSize); + MOZ_RELEASE_ASSERT(unsigned(*iter.Data()) == (kTotalSize - kLastSegmentSize - kInitialSize - kSmallWrite) % 37); + + // Clear. + + bl.Clear(); + MOZ_RELEASE_ASSERT(bl.Size() == 0); + MOZ_RELEASE_ASSERT(bl.Iter().Done()); + + // Move assignment. + + const size_t kSmallCapacity = 8; + + BufferList bl2(0, kSmallCapacity, kSmallCapacity); + bl2.WriteBytes(toWrite, kSmallWrite); + bl2.WriteBytes(toWrite, kSmallWrite); + bl2.WriteBytes(toWrite, kSmallWrite); + + bl = mozilla::Move(bl2); + MOZ_RELEASE_ASSERT(bl2.Size() == 0); + MOZ_RELEASE_ASSERT(bl2.Iter().Done()); + + iter = bl.Iter(); + MOZ_RELEASE_ASSERT(iter.AdvanceAcrossSegments(bl, kSmallWrite * 3)); + MOZ_RELEASE_ASSERT(iter.Done()); + + // MoveFallible + + bool success; + bl2 = bl.MoveFallible<InfallibleAllocPolicy>(&success); + MOZ_RELEASE_ASSERT(success); + MOZ_RELEASE_ASSERT(bl.Size() == 0); + MOZ_RELEASE_ASSERT(bl.Iter().Done()); + MOZ_RELEASE_ASSERT(bl2.Size() == kSmallWrite * 3); + + iter = bl2.Iter(); + MOZ_RELEASE_ASSERT(iter.AdvanceAcrossSegments(bl2, kSmallWrite * 3)); + MOZ_RELEASE_ASSERT(iter.Done()); + + bl = bl2.MoveFallible<InfallibleAllocPolicy>(&success); + + // Borrowing. + + const size_t kBorrowStart = 4; + const size_t kBorrowSize = 24; + + iter = bl.Iter(); + iter.Advance(bl, kBorrowStart); + bl2 = bl.Borrow<InfallibleAllocPolicy>(iter, kBorrowSize, &success); + MOZ_RELEASE_ASSERT(success); + MOZ_RELEASE_ASSERT(bl2.Size() == kBorrowSize); + + MOZ_RELEASE_ASSERT(iter.AdvanceAcrossSegments(bl, kSmallWrite * 3 - kBorrowSize - kBorrowStart)); + MOZ_RELEASE_ASSERT(iter.Done()); + + iter = bl2.Iter(); + MOZ_RELEASE_ASSERT(iter.AdvanceAcrossSegments(bl2, kBorrowSize)); + MOZ_RELEASE_ASSERT(iter.Done()); + + BufferList::IterImpl iter1(bl.Iter()), iter2(bl2.Iter()); + iter1.Advance(bl, kBorrowStart); + MOZ_RELEASE_ASSERT(iter1.Data() == iter2.Data()); + MOZ_RELEASE_ASSERT(iter1.AdvanceAcrossSegments(bl, kBorrowSize - 5)); + MOZ_RELEASE_ASSERT(iter2.AdvanceAcrossSegments(bl2, kBorrowSize - 5)); + MOZ_RELEASE_ASSERT(iter1.Data() == iter2.Data()); + + // Extracting. + + const size_t kExtractStart = 8; + const size_t kExtractSize = 24; + const size_t kExtractOverSize = 1000; + + iter = bl.Iter(); + iter.Advance(bl, kExtractStart); + bl2 = bl.Extract(iter, kExtractSize, &success); + MOZ_RELEASE_ASSERT(success); + MOZ_RELEASE_ASSERT(bl2.Size() == kExtractSize); + + BufferList bl3 = bl.Extract(iter, kExtractOverSize, &success); + MOZ_RELEASE_ASSERT(!success); + + MOZ_RELEASE_ASSERT(iter.AdvanceAcrossSegments(bl, kSmallWrite * 3 - kExtractSize - kExtractStart)); + MOZ_RELEASE_ASSERT(iter.Done()); + + iter = bl2.Iter(); + MOZ_RELEASE_ASSERT(iter.AdvanceAcrossSegments(bl2, kExtractSize)); + MOZ_RELEASE_ASSERT(iter.Done()); + + return 0; +} diff --git a/mfbt/tests/TestCasting.cpp b/mfbt/tests/TestCasting.cpp new file mode 100644 index 000000000..c8bd12488 --- /dev/null +++ b/mfbt/tests/TestCasting.cpp @@ -0,0 +1,112 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Casting.h" + +#include <stdint.h> + +using mozilla::BitwiseCast; +using mozilla::detail::IsInBounds; + +template<typename Uint, typename Ulong, bool = (sizeof(Uint) == sizeof(Ulong))> +struct UintUlongBitwiseCast; + +template<typename Uint, typename Ulong> +struct UintUlongBitwiseCast<Uint, Ulong, true> +{ + static void test() + { + MOZ_RELEASE_ASSERT(BitwiseCast<Ulong>(Uint(8675309)) == Ulong(8675309)); + } +}; + +template<typename Uint, typename Ulong> +struct UintUlongBitwiseCast<Uint, Ulong, false> +{ + static void test() { } +}; + +static void +TestBitwiseCast() +{ + MOZ_RELEASE_ASSERT(BitwiseCast<int>(int(8675309)) == int(8675309)); + UintUlongBitwiseCast<unsigned int, unsigned long>::test(); +} + +static void +TestSameSize() +{ + MOZ_RELEASE_ASSERT((IsInBounds<int16_t, int16_t>(int16_t(0)))); + MOZ_RELEASE_ASSERT((IsInBounds<int16_t, int16_t>(int16_t(INT16_MIN)))); + MOZ_RELEASE_ASSERT((IsInBounds<int16_t, int16_t>(int16_t(INT16_MAX)))); + MOZ_RELEASE_ASSERT((IsInBounds<uint16_t, uint16_t>(uint16_t(UINT16_MAX)))); + MOZ_RELEASE_ASSERT((IsInBounds<uint16_t, int16_t>(uint16_t(0)))); + MOZ_RELEASE_ASSERT((!IsInBounds<uint16_t, int16_t>(uint16_t(-1)))); + MOZ_RELEASE_ASSERT((!IsInBounds<int16_t, uint16_t>(int16_t(-1)))); + MOZ_RELEASE_ASSERT((IsInBounds<int16_t, uint16_t>(int16_t(INT16_MAX)))); + MOZ_RELEASE_ASSERT((!IsInBounds<int16_t, uint16_t>(int16_t(INT16_MIN)))); + MOZ_RELEASE_ASSERT((IsInBounds<int32_t, uint32_t>(int32_t(INT32_MAX)))); + MOZ_RELEASE_ASSERT((!IsInBounds<int32_t, uint32_t>(int32_t(INT32_MIN)))); +} + +static void +TestToBiggerSize() +{ + MOZ_RELEASE_ASSERT((IsInBounds<int16_t, int32_t>(int16_t(0)))); + MOZ_RELEASE_ASSERT((IsInBounds<int16_t, int32_t>(int16_t(INT16_MIN)))); + MOZ_RELEASE_ASSERT((IsInBounds<int16_t, int32_t>(int16_t(INT16_MAX)))); + MOZ_RELEASE_ASSERT((IsInBounds<uint16_t, uint32_t>(uint16_t(UINT16_MAX)))); + MOZ_RELEASE_ASSERT((IsInBounds<uint16_t, int32_t>(uint16_t(0)))); + MOZ_RELEASE_ASSERT((IsInBounds<uint16_t, int32_t>(uint16_t(-1)))); + MOZ_RELEASE_ASSERT((!IsInBounds<int16_t, uint32_t>(int16_t(-1)))); + MOZ_RELEASE_ASSERT((IsInBounds<int16_t, uint32_t>(int16_t(INT16_MAX)))); + MOZ_RELEASE_ASSERT((!IsInBounds<int16_t, uint32_t>(int16_t(INT16_MIN)))); + MOZ_RELEASE_ASSERT((IsInBounds<int32_t, uint64_t>(int32_t(INT32_MAX)))); + MOZ_RELEASE_ASSERT((!IsInBounds<int32_t, uint64_t>(int32_t(INT32_MIN)))); +} + +static void +TestToSmallerSize() +{ + MOZ_RELEASE_ASSERT((IsInBounds<int16_t, int8_t>(int16_t(0)))); + MOZ_RELEASE_ASSERT((!IsInBounds<int16_t, int8_t>(int16_t(INT16_MIN)))); + MOZ_RELEASE_ASSERT((!IsInBounds<int16_t, int8_t>(int16_t(INT16_MAX)))); + MOZ_RELEASE_ASSERT((!IsInBounds<uint16_t, uint8_t>(uint16_t(UINT16_MAX)))); + MOZ_RELEASE_ASSERT((IsInBounds<uint16_t, int8_t>(uint16_t(0)))); + MOZ_RELEASE_ASSERT((!IsInBounds<uint16_t, int8_t>(uint16_t(-1)))); + MOZ_RELEASE_ASSERT((!IsInBounds<int16_t, uint8_t>(int16_t(-1)))); + MOZ_RELEASE_ASSERT((!IsInBounds<int16_t, uint8_t>(int16_t(INT16_MAX)))); + MOZ_RELEASE_ASSERT((!IsInBounds<int16_t, uint8_t>(int16_t(INT16_MIN)))); + MOZ_RELEASE_ASSERT((!IsInBounds<int32_t, uint16_t>(int32_t(INT32_MAX)))); + MOZ_RELEASE_ASSERT((!IsInBounds<int32_t, uint16_t>(int32_t(INT32_MIN)))); + + // Boundary cases + MOZ_RELEASE_ASSERT((!IsInBounds<int64_t, int32_t>(int64_t(INT32_MIN) - 1))); + MOZ_RELEASE_ASSERT((IsInBounds<int64_t, int32_t>(int64_t(INT32_MIN)))); + MOZ_RELEASE_ASSERT((IsInBounds<int64_t, int32_t>(int64_t(INT32_MIN) + 1))); + MOZ_RELEASE_ASSERT((IsInBounds<int64_t, int32_t>(int64_t(INT32_MAX) - 1))); + MOZ_RELEASE_ASSERT((IsInBounds<int64_t, int32_t>(int64_t(INT32_MAX)))); + MOZ_RELEASE_ASSERT((!IsInBounds<int64_t, int32_t>(int64_t(INT32_MAX) + 1))); + + MOZ_RELEASE_ASSERT((!IsInBounds<int64_t, uint32_t>(int64_t(-1)))); + MOZ_RELEASE_ASSERT((IsInBounds<int64_t, uint32_t>(int64_t(0)))); + MOZ_RELEASE_ASSERT((IsInBounds<int64_t, uint32_t>(int64_t(1)))); + MOZ_RELEASE_ASSERT((IsInBounds<int64_t, uint32_t>(int64_t(UINT32_MAX) - 1))); + MOZ_RELEASE_ASSERT((IsInBounds<int64_t, uint32_t>(int64_t(UINT32_MAX)))); + MOZ_RELEASE_ASSERT((!IsInBounds<int64_t, uint32_t>(int64_t(UINT32_MAX) + 1))); +} + +int +main() +{ + TestBitwiseCast(); + + TestSameSize(); + TestToBiggerSize(); + TestToSmallerSize(); + + return 0; +} diff --git a/mfbt/tests/TestCeilingFloor.cpp b/mfbt/tests/TestCeilingFloor.cpp new file mode 100644 index 000000000..f1c50dec8 --- /dev/null +++ b/mfbt/tests/TestCeilingFloor.cpp @@ -0,0 +1,89 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/MathAlgorithms.h" + +using mozilla::CeilingLog2; +using mozilla::FloorLog2; +using mozilla::RoundUpPow2; + +static void +TestCeiling() +{ + for (uint32_t i = 0; i <= 1; i++) { + MOZ_RELEASE_ASSERT(CeilingLog2(i) == 0); + } + for (uint32_t i = 2; i <= 2; i++) { + MOZ_RELEASE_ASSERT(CeilingLog2(i) == 1); + } + for (uint32_t i = 3; i <= 4; i++) { + MOZ_RELEASE_ASSERT(CeilingLog2(i) == 2); + } + for (uint32_t i = 5; i <= 8; i++) { + MOZ_RELEASE_ASSERT(CeilingLog2(i) == 3); + } + for (uint32_t i = 9; i <= 16; i++) { + MOZ_RELEASE_ASSERT(CeilingLog2(i) == 4); + } +} + +static void +TestFloor() +{ + for (uint32_t i = 0; i <= 1; i++) { + MOZ_RELEASE_ASSERT(FloorLog2(i) == 0); + } + for (uint32_t i = 2; i <= 3; i++) { + MOZ_RELEASE_ASSERT(FloorLog2(i) == 1); + } + for (uint32_t i = 4; i <= 7; i++) { + MOZ_RELEASE_ASSERT(FloorLog2(i) == 2); + } + for (uint32_t i = 8; i <= 15; i++) { + MOZ_RELEASE_ASSERT(FloorLog2(i) == 3); + } + for (uint32_t i = 16; i <= 31; i++) { + MOZ_RELEASE_ASSERT(FloorLog2(i) == 4); + } +} + +static void +TestRoundUpPow2() +{ + MOZ_RELEASE_ASSERT(RoundUpPow2(0) == 1); + MOZ_RELEASE_ASSERT(RoundUpPow2(1) == 1); + MOZ_RELEASE_ASSERT(RoundUpPow2(2) == 2); + MOZ_RELEASE_ASSERT(RoundUpPow2(3) == 4); + MOZ_RELEASE_ASSERT(RoundUpPow2(4) == 4); + MOZ_RELEASE_ASSERT(RoundUpPow2(5) == 8); + MOZ_RELEASE_ASSERT(RoundUpPow2(6) == 8); + MOZ_RELEASE_ASSERT(RoundUpPow2(7) == 8); + MOZ_RELEASE_ASSERT(RoundUpPow2(8) == 8); + MOZ_RELEASE_ASSERT(RoundUpPow2(9) == 16); + + MOZ_RELEASE_ASSERT(RoundUpPow2(15) == 16); + MOZ_RELEASE_ASSERT(RoundUpPow2(16) == 16); + MOZ_RELEASE_ASSERT(RoundUpPow2(17) == 32); + + MOZ_RELEASE_ASSERT(RoundUpPow2(31) == 32); + MOZ_RELEASE_ASSERT(RoundUpPow2(32) == 32); + MOZ_RELEASE_ASSERT(RoundUpPow2(33) == 64); + + size_t MaxPow2 = size_t(1) << (sizeof(size_t) * CHAR_BIT - 1); + MOZ_RELEASE_ASSERT(RoundUpPow2(MaxPow2 - 1) == MaxPow2); + MOZ_RELEASE_ASSERT(RoundUpPow2(MaxPow2) == MaxPow2); + // not valid to round up when past the max power of two +} + +int +main() +{ + TestCeiling(); + TestFloor(); + + TestRoundUpPow2(); + return 0; +} diff --git a/mfbt/tests/TestCheckedInt.cpp b/mfbt/tests/TestCheckedInt.cpp new file mode 100644 index 000000000..7ded8e350 --- /dev/null +++ b/mfbt/tests/TestCheckedInt.cpp @@ -0,0 +1,626 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/CheckedInt.h" + +#include <iostream> +#include <climits> + +using namespace mozilla; + +int gIntegerTypesTested = 0; +int gTestsPassed = 0; +int gTestsFailed = 0; + +void verifyImplFunction(bool aX, bool aExpected, + const char* aFile, int aLine, + int aSize, bool aIsTSigned) +{ + if (aX == aExpected) { + gTestsPassed++; + } else { + gTestsFailed++; + std::cerr << "Test failed at " << aFile << ":" << aLine; + std::cerr << " with T a "; + if (aIsTSigned) { + std::cerr << "signed"; + } else { + std::cerr << "unsigned"; + } + std::cerr << " " << CHAR_BIT * aSize << "-bit integer type" << std::endl; + } +} + +#define VERIFY_IMPL(x, expected) \ + verifyImplFunction((x), \ + (expected), \ + __FILE__, \ + __LINE__, \ + sizeof(T), \ + IsSigned<T>::value) + +#define VERIFY(x) VERIFY_IMPL(x, true) +#define VERIFY_IS_FALSE(x) VERIFY_IMPL(x, false) +#define VERIFY_IS_VALID(x) VERIFY_IMPL((x).isValid(), true) +#define VERIFY_IS_INVALID(x) VERIFY_IMPL((x).isValid(), false) +#define VERIFY_IS_VALID_IF(x,condition) VERIFY_IMPL((x).isValid(), (condition)) + +template<typename T, size_t Size = sizeof(T)> +struct testTwiceBiggerType +{ + static void run() + { + VERIFY(detail::IsSupported<typename detail::TwiceBiggerType<T>::Type>::value); + VERIFY(sizeof(typename detail::TwiceBiggerType<T>::Type) == 2 * sizeof(T)); + VERIFY(bool(IsSigned<typename detail::TwiceBiggerType<T>::Type>::value) == + bool(IsSigned<T>::value)); + } +}; + +template<typename T> +struct testTwiceBiggerType<T, 8> +{ + static void run() + { + VERIFY_IS_FALSE(detail::IsSupported< + typename detail::TwiceBiggerType<T>::Type + >::value); + } +}; + + +template<typename T> +void test() +{ + static bool alreadyRun = false; + // Integer types from different families may just be typedefs for types from + // other families. E.g. int32_t might be just a typedef for int. No point + // re-running the same tests then. + if (alreadyRun) { + return; + } + alreadyRun = true; + + VERIFY(detail::IsSupported<T>::value); + const bool isTSigned = IsSigned<T>::value; + VERIFY(bool(isTSigned) == !bool(T(-1) > T(0))); + + testTwiceBiggerType<T>::run(); + + typedef typename MakeUnsigned<T>::Type unsignedT; + + VERIFY(sizeof(unsignedT) == sizeof(T)); + VERIFY(IsSigned<unsignedT>::value == false); + + const CheckedInt<T> max(MaxValue<T>::value); + const CheckedInt<T> min(MinValue<T>::value); + + // Check MinValue and MaxValue, since they are custom implementations and a + // mistake there could potentially NOT be caught by any other tests... while + // making everything wrong! + + unsignedT bit = 1; + unsignedT unsignedMinValue(min.value()); + unsignedT unsignedMaxValue(max.value()); + for (size_t i = 0; i < sizeof(T) * CHAR_BIT - 1; i++) { + VERIFY((unsignedMinValue & bit) == 0); + bit <<= 1; + } + VERIFY((unsignedMinValue & bit) == (isTSigned ? bit : unsignedT(0))); + VERIFY(unsignedMaxValue == unsignedT(~unsignedMinValue)); + + const CheckedInt<T> zero(0); + const CheckedInt<T> one(1); + const CheckedInt<T> two(2); + const CheckedInt<T> three(3); + const CheckedInt<T> four(4); + + /* Addition / subtraction checks */ + + VERIFY_IS_VALID(zero + zero); + VERIFY(zero + zero == zero); + VERIFY_IS_FALSE(zero + zero == one); // Check == doesn't always return true + VERIFY_IS_VALID(zero + one); + VERIFY(zero + one == one); + VERIFY_IS_VALID(one + one); + VERIFY(one + one == two); + + const CheckedInt<T> maxMinusOne = max - one; + const CheckedInt<T> maxMinusTwo = max - two; + VERIFY_IS_VALID(maxMinusOne); + VERIFY_IS_VALID(maxMinusTwo); + VERIFY_IS_VALID(maxMinusOne + one); + VERIFY_IS_VALID(maxMinusTwo + one); + VERIFY_IS_VALID(maxMinusTwo + two); + VERIFY(maxMinusOne + one == max); + VERIFY(maxMinusTwo + one == maxMinusOne); + VERIFY(maxMinusTwo + two == max); + + VERIFY_IS_VALID(max + zero); + VERIFY_IS_VALID(max - zero); + VERIFY_IS_INVALID(max + one); + VERIFY_IS_INVALID(max + two); + VERIFY_IS_INVALID(max + maxMinusOne); + VERIFY_IS_INVALID(max + max); + + const CheckedInt<T> minPlusOne = min + one; + const CheckedInt<T> minPlusTwo = min + two; + VERIFY_IS_VALID(minPlusOne); + VERIFY_IS_VALID(minPlusTwo); + VERIFY_IS_VALID(minPlusOne - one); + VERIFY_IS_VALID(minPlusTwo - one); + VERIFY_IS_VALID(minPlusTwo - two); + VERIFY(minPlusOne - one == min); + VERIFY(minPlusTwo - one == minPlusOne); + VERIFY(minPlusTwo - two == min); + + const CheckedInt<T> minMinusOne = min - one; + VERIFY_IS_VALID(min + zero); + VERIFY_IS_VALID(min - zero); + VERIFY_IS_INVALID(min - one); + VERIFY_IS_INVALID(min - two); + VERIFY_IS_INVALID(min - minMinusOne); + VERIFY_IS_VALID(min - min); + + const CheckedInt<T> maxOverTwo = max / two; + VERIFY_IS_VALID(maxOverTwo + maxOverTwo); + VERIFY_IS_VALID(maxOverTwo + one); + VERIFY((maxOverTwo + one) - one == maxOverTwo); + VERIFY_IS_VALID(maxOverTwo - maxOverTwo); + VERIFY(maxOverTwo - maxOverTwo == zero); + + const CheckedInt<T> minOverTwo = min / two; + VERIFY_IS_VALID(minOverTwo + minOverTwo); + VERIFY_IS_VALID(minOverTwo + one); + VERIFY((minOverTwo + one) - one == minOverTwo); + VERIFY_IS_VALID(minOverTwo - minOverTwo); + VERIFY(minOverTwo - minOverTwo == zero); + + VERIFY_IS_INVALID(min - one); + VERIFY_IS_INVALID(min - two); + + if (isTSigned) { + VERIFY_IS_INVALID(min + min); + VERIFY_IS_INVALID(minOverTwo + minOverTwo + minOverTwo); + VERIFY_IS_INVALID(zero - min + min); + VERIFY_IS_INVALID(one - min + min); + } + + /* Modulo checks */ + VERIFY_IS_INVALID(zero % zero); + VERIFY_IS_INVALID(one % zero); + VERIFY_IS_VALID(zero % one); + VERIFY_IS_VALID(zero % max); + VERIFY_IS_VALID(one % max); + VERIFY_IS_VALID(max % one); + VERIFY_IS_VALID(max % max); + if (isTSigned) { + const CheckedInt<T> minusOne = zero - one; + VERIFY_IS_INVALID(minusOne % minusOne); + VERIFY_IS_INVALID(zero % minusOne); + VERIFY_IS_INVALID(one % minusOne); + VERIFY_IS_INVALID(minusOne % one); + + VERIFY_IS_INVALID(min % min); + VERIFY_IS_INVALID(zero % min); + VERIFY_IS_INVALID(min % one); + } + + /* Unary operator- checks */ + + const CheckedInt<T> negOne = -one; + const CheckedInt<T> negTwo = -two; + + if (isTSigned) { + VERIFY_IS_VALID(-max); + VERIFY_IS_INVALID(-min); + VERIFY(-max - min == one); + VERIFY_IS_VALID(-max - one); + VERIFY_IS_VALID(negOne); + VERIFY_IS_VALID(-max + negOne); + VERIFY_IS_VALID(negOne + one); + VERIFY(negOne + one == zero); + VERIFY_IS_VALID(negTwo); + VERIFY_IS_VALID(negOne + negOne); + VERIFY(negOne + negOne == negTwo); + } else { + VERIFY_IS_INVALID(-max); + VERIFY_IS_VALID(-min); + VERIFY(min == zero); + VERIFY_IS_INVALID(negOne); + } + + /* multiplication checks */ + + VERIFY_IS_VALID(zero * zero); + VERIFY(zero * zero == zero); + VERIFY_IS_VALID(zero * one); + VERIFY(zero * one == zero); + VERIFY_IS_VALID(one * zero); + VERIFY(one * zero == zero); + VERIFY_IS_VALID(one * one); + VERIFY(one * one == one); + VERIFY_IS_VALID(one * three); + VERIFY(one * three == three); + VERIFY_IS_VALID(two * two); + VERIFY(two * two == four); + + VERIFY_IS_INVALID(max * max); + VERIFY_IS_INVALID(maxOverTwo * max); + VERIFY_IS_INVALID(maxOverTwo * maxOverTwo); + + const CheckedInt<T> maxApproxSqrt(T(T(1) << (CHAR_BIT*sizeof(T)/2))); + + VERIFY_IS_VALID(maxApproxSqrt); + VERIFY_IS_VALID(maxApproxSqrt * two); + VERIFY_IS_INVALID(maxApproxSqrt * maxApproxSqrt); + VERIFY_IS_INVALID(maxApproxSqrt * maxApproxSqrt * maxApproxSqrt); + + if (isTSigned) { + VERIFY_IS_INVALID(min * min); + VERIFY_IS_INVALID(minOverTwo * min); + VERIFY_IS_INVALID(minOverTwo * minOverTwo); + + const CheckedInt<T> minApproxSqrt = -maxApproxSqrt; + + VERIFY_IS_VALID(minApproxSqrt); + VERIFY_IS_VALID(minApproxSqrt * two); + VERIFY_IS_INVALID(minApproxSqrt * maxApproxSqrt); + VERIFY_IS_INVALID(minApproxSqrt * minApproxSqrt); + } + + // make sure to check all 4 paths in signed multiplication validity check. + // test positive * positive + VERIFY_IS_VALID(max * one); + VERIFY(max * one == max); + VERIFY_IS_INVALID(max * two); + VERIFY_IS_VALID(maxOverTwo * two); + VERIFY((maxOverTwo + maxOverTwo) == (maxOverTwo * two)); + + if (isTSigned) { + // test positive * negative + VERIFY_IS_VALID(max * negOne); + VERIFY_IS_VALID(-max); + VERIFY(max * negOne == -max); + VERIFY_IS_VALID(one * min); + VERIFY_IS_INVALID(max * negTwo); + VERIFY_IS_VALID(maxOverTwo * negTwo); + VERIFY_IS_VALID(two * minOverTwo); + VERIFY_IS_VALID((maxOverTwo + one) * negTwo); + VERIFY_IS_INVALID((maxOverTwo + two) * negTwo); + VERIFY_IS_INVALID(two * (minOverTwo - one)); + + // test negative * positive + VERIFY_IS_VALID(min * one); + VERIFY_IS_VALID(minPlusOne * one); + VERIFY_IS_INVALID(min * two); + VERIFY_IS_VALID(minOverTwo * two); + VERIFY(minOverTwo * two == min); + VERIFY_IS_INVALID((minOverTwo - one) * negTwo); + VERIFY_IS_INVALID(negTwo * max); + VERIFY_IS_VALID(minOverTwo * two); + VERIFY(minOverTwo * two == min); + VERIFY_IS_VALID(negTwo * maxOverTwo); + VERIFY_IS_INVALID((minOverTwo - one) * two); + VERIFY_IS_VALID(negTwo * (maxOverTwo + one)); + VERIFY_IS_INVALID(negTwo * (maxOverTwo + two)); + + // test negative * negative + VERIFY_IS_INVALID(min * negOne); + VERIFY_IS_VALID(minPlusOne * negOne); + VERIFY(minPlusOne * negOne == max); + VERIFY_IS_INVALID(min * negTwo); + VERIFY_IS_INVALID(minOverTwo * negTwo); + VERIFY_IS_INVALID(negOne * min); + VERIFY_IS_VALID(negOne * minPlusOne); + VERIFY(negOne * minPlusOne == max); + VERIFY_IS_INVALID(negTwo * min); + VERIFY_IS_INVALID(negTwo * minOverTwo); + } + + /* Division checks */ + + VERIFY_IS_VALID(one / one); + VERIFY(one / one == one); + VERIFY_IS_VALID(three / three); + VERIFY(three / three == one); + VERIFY_IS_VALID(four / two); + VERIFY(four / two == two); + VERIFY((four*three)/four == three); + + // Check that div by zero is invalid + VERIFY_IS_INVALID(zero / zero); + VERIFY_IS_INVALID(one / zero); + VERIFY_IS_INVALID(two / zero); + VERIFY_IS_INVALID(negOne / zero); + VERIFY_IS_INVALID(max / zero); + VERIFY_IS_INVALID(min / zero); + + if (isTSigned) { + // Check that min / -1 is invalid + VERIFY_IS_INVALID(min / negOne); + + // Check that the test for div by -1 isn't banning other numerators than min + VERIFY_IS_VALID(one / negOne); + VERIFY_IS_VALID(zero / negOne); + VERIFY_IS_VALID(negOne / negOne); + VERIFY_IS_VALID(max / negOne); + } + + /* Check that invalidity is correctly preserved by arithmetic ops */ + + const CheckedInt<T> someInvalid = max + max; + VERIFY_IS_INVALID(someInvalid + zero); + VERIFY_IS_INVALID(someInvalid - zero); + VERIFY_IS_INVALID(zero + someInvalid); + VERIFY_IS_INVALID(zero - someInvalid); + VERIFY_IS_INVALID(-someInvalid); + VERIFY_IS_INVALID(someInvalid * zero); + VERIFY_IS_INVALID(someInvalid * one); + VERIFY_IS_INVALID(zero * someInvalid); + VERIFY_IS_INVALID(one * someInvalid); + VERIFY_IS_INVALID(someInvalid / zero); + VERIFY_IS_INVALID(someInvalid / one); + VERIFY_IS_INVALID(zero / someInvalid); + VERIFY_IS_INVALID(one / someInvalid); + VERIFY_IS_INVALID(someInvalid % zero); + VERIFY_IS_INVALID(someInvalid % one); + VERIFY_IS_INVALID(zero % someInvalid); + VERIFY_IS_INVALID(one % someInvalid); + VERIFY_IS_INVALID(someInvalid + someInvalid); + VERIFY_IS_INVALID(someInvalid - someInvalid); + VERIFY_IS_INVALID(someInvalid * someInvalid); + VERIFY_IS_INVALID(someInvalid / someInvalid); + VERIFY_IS_INVALID(someInvalid % someInvalid); + + // Check that mixing checked integers with plain integers in expressions is + // allowed + + VERIFY(one + T(2) == three); + VERIFY(2 + one == three); + { + CheckedInt<T> x = one; + x += 2; + VERIFY(x == three); + } + VERIFY(two - 1 == one); + VERIFY(2 - one == one); + { + CheckedInt<T> x = two; + x -= 1; + VERIFY(x == one); + } + VERIFY(one * 2 == two); + VERIFY(2 * one == two); + { + CheckedInt<T> x = one; + x *= 2; + VERIFY(x == two); + } + VERIFY(four / 2 == two); + VERIFY(4 / two == two); + { + CheckedInt<T> x = four; + x /= 2; + VERIFY(x == two); + } + VERIFY(three % 2 == one); + VERIFY(3 % two == one); + { + CheckedInt<T> x = three; + x %= 2; + VERIFY(x == one); + } + + VERIFY(one == 1); + VERIFY(1 == one); + VERIFY_IS_FALSE(two == 1); + VERIFY_IS_FALSE(1 == two); + VERIFY_IS_FALSE(someInvalid == 1); + VERIFY_IS_FALSE(1 == someInvalid); + + // Check that compound operators work when both sides of the expression + // are checked integers + { + CheckedInt<T> x = one; + x += two; + VERIFY(x == three); + } + { + CheckedInt<T> x = two; + x -= one; + VERIFY(x == one); + } + { + CheckedInt<T> x = one; + x *= two; + VERIFY(x == two); + } + { + CheckedInt<T> x = four; + x /= two; + VERIFY(x == two); + } + { + CheckedInt<T> x = three; + x %= two; + VERIFY(x == one); + } + + // Check that compound operators work when both sides of the expression + // are checked integers and the right-hand side is invalid + { + CheckedInt<T> x = one; + x += someInvalid; + VERIFY_IS_INVALID(x); + } + { + CheckedInt<T> x = two; + x -= someInvalid; + VERIFY_IS_INVALID(x); + } + { + CheckedInt<T> x = one; + x *= someInvalid; + VERIFY_IS_INVALID(x); + } + { + CheckedInt<T> x = four; + x /= someInvalid; + VERIFY_IS_INVALID(x); + } + { + CheckedInt<T> x = three; + x %= someInvalid; + VERIFY_IS_INVALID(x); + } + + // Check simple casting between different signedness and sizes. + { + CheckedInt<uint8_t> foo = CheckedInt<uint16_t>(2).toChecked<uint8_t>(); + VERIFY_IS_VALID(foo); + VERIFY(foo == 2); + } + { + CheckedInt<uint8_t> foo = CheckedInt<uint16_t>(255).toChecked<uint8_t>(); + VERIFY_IS_VALID(foo); + VERIFY(foo == 255); + } + { + CheckedInt<uint8_t> foo = CheckedInt<uint16_t>(256).toChecked<uint8_t>(); + VERIFY_IS_INVALID(foo); + } + { + CheckedInt<uint8_t> foo = CheckedInt<int8_t>(-2).toChecked<uint8_t>(); + VERIFY_IS_INVALID(foo); + } + + // Check that construction of CheckedInt from an integer value of a + // mismatched type is checked Also check casting between all types. + + #define VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE2(U,V,PostVExpr) \ + { \ + bool isUSigned = IsSigned<U>::value; \ + VERIFY_IS_VALID(CheckedInt<T>(V( 0)PostVExpr)); \ + VERIFY_IS_VALID(CheckedInt<T>(V( 1)PostVExpr)); \ + VERIFY_IS_VALID(CheckedInt<T>(V(100)PostVExpr)); \ + if (isUSigned) { \ + VERIFY_IS_VALID_IF(CheckedInt<T>(V(-1)PostVExpr), isTSigned); \ + } \ + if (sizeof(U) > sizeof(T)) { \ + VERIFY_IS_INVALID(CheckedInt<T>(V(MaxValue<T>::value)PostVExpr + one.value())); \ + } \ + VERIFY_IS_VALID_IF(CheckedInt<T>(MaxValue<U>::value), \ + (sizeof(T) > sizeof(U) || ((sizeof(T) == sizeof(U)) && (isUSigned || !isTSigned)))); \ + VERIFY_IS_VALID_IF(CheckedInt<T>(MinValue<U>::value), \ + isUSigned == false ? 1 \ + : bool(isTSigned) == false ? 0 \ + : sizeof(T) >= sizeof(U)); \ + } + #define VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(U) \ + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE2(U,U,+zero) \ + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE2(U,CheckedInt<U>,.toChecked<T>()) + + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(int8_t) + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(uint8_t) + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(int16_t) + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(uint16_t) + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(int32_t) + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(uint32_t) + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(int64_t) + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(uint64_t) + + typedef signed char signedChar; + typedef unsigned char unsignedChar; + typedef unsigned short unsignedShort; + typedef unsigned int unsignedInt; + typedef unsigned long unsignedLong; + typedef long long longLong; + typedef unsigned long long unsignedLongLong; + + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(char) + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(signedChar) + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(unsignedChar) + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(short) + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(unsignedShort) + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(int) + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(unsignedInt) + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(long) + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(unsignedLong) + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(longLong) + VERIFY_CONSTRUCTION_FROM_INTEGER_TYPE(unsignedLongLong) + + /* Test increment/decrement operators */ + + CheckedInt<T> x, y; + x = one; + y = x++; + VERIFY(x == two); + VERIFY(y == one); + x = one; + y = ++x; + VERIFY(x == two); + VERIFY(y == two); + x = one; + y = x--; + VERIFY(x == zero); + VERIFY(y == one); + x = one; + y = --x; + VERIFY(x == zero); + VERIFY(y == zero); + x = max; + VERIFY_IS_VALID(x++); + x = max; + VERIFY_IS_INVALID(++x); + x = min; + VERIFY_IS_VALID(x--); + x = min; + VERIFY_IS_INVALID(--x); + + gIntegerTypesTested++; +} + +int +main() +{ + test<int8_t>(); + test<uint8_t>(); + test<int16_t>(); + test<uint16_t>(); + test<int32_t>(); + test<uint32_t>(); + test<int64_t>(); + test<uint64_t>(); + + test<char>(); + test<signed char>(); + test<unsigned char>(); + test<short>(); + test<unsigned short>(); + test<int>(); + test<unsigned int>(); + test<long>(); + test<unsigned long>(); + test<long long>(); + test<unsigned long long>(); + + const int MIN_TYPES_TESTED = 9; + if (gIntegerTypesTested < MIN_TYPES_TESTED) { + std::cerr << "Only " << gIntegerTypesTested << " have been tested. " + << "This should not be less than " << MIN_TYPES_TESTED << "." + << std::endl; + gTestsFailed++; + } + + std::cerr << gTestsFailed << " tests failed, " + << gTestsPassed << " tests passed out of " + << gTestsFailed + gTestsPassed + << " tests, covering " << gIntegerTypesTested + << " distinct integer types." << std::endl; + + return gTestsFailed > 0; +} diff --git a/mfbt/tests/TestCountPopulation.cpp b/mfbt/tests/TestCountPopulation.cpp new file mode 100644 index 000000000..272a0dc34 --- /dev/null +++ b/mfbt/tests/TestCountPopulation.cpp @@ -0,0 +1,34 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/MathAlgorithms.h" + +using mozilla::CountPopulation32; + +static void +TestCountPopulation32() +{ + MOZ_RELEASE_ASSERT(CountPopulation32(0xFFFFFFFF) == 32); + MOZ_RELEASE_ASSERT(CountPopulation32(0xF0FF1000) == 13); + MOZ_RELEASE_ASSERT(CountPopulation32(0x7F8F0001) == 13); + MOZ_RELEASE_ASSERT(CountPopulation32(0x3FFF0100) == 15); + MOZ_RELEASE_ASSERT(CountPopulation32(0x1FF50010) == 12); + MOZ_RELEASE_ASSERT(CountPopulation32(0x00800000) == 1); + MOZ_RELEASE_ASSERT(CountPopulation32(0x00400000) == 1); + MOZ_RELEASE_ASSERT(CountPopulation32(0x00008000) == 1); + MOZ_RELEASE_ASSERT(CountPopulation32(0x00004000) == 1); + MOZ_RELEASE_ASSERT(CountPopulation32(0x00000080) == 1); + MOZ_RELEASE_ASSERT(CountPopulation32(0x00000040) == 1); + MOZ_RELEASE_ASSERT(CountPopulation32(0x00000001) == 1); + MOZ_RELEASE_ASSERT(CountPopulation32(0x00000000) == 0); +} + +int +main() +{ + TestCountPopulation32(); + return 0; +} diff --git a/mfbt/tests/TestCountZeroes.cpp b/mfbt/tests/TestCountZeroes.cpp new file mode 100644 index 000000000..799ee8421 --- /dev/null +++ b/mfbt/tests/TestCountZeroes.cpp @@ -0,0 +1,102 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/MathAlgorithms.h" + +using mozilla::CountLeadingZeroes32; +using mozilla::CountLeadingZeroes64; +using mozilla::CountTrailingZeroes32; +using mozilla::CountTrailingZeroes64; + +static void +TestLeadingZeroes32() +{ + MOZ_RELEASE_ASSERT(CountLeadingZeroes32(0xF0FF1000) == 0); + MOZ_RELEASE_ASSERT(CountLeadingZeroes32(0x7F8F0001) == 1); + MOZ_RELEASE_ASSERT(CountLeadingZeroes32(0x3FFF0100) == 2); + MOZ_RELEASE_ASSERT(CountLeadingZeroes32(0x1FF50010) == 3); + MOZ_RELEASE_ASSERT(CountLeadingZeroes32(0x00800000) == 8); + MOZ_RELEASE_ASSERT(CountLeadingZeroes32(0x00400000) == 9); + MOZ_RELEASE_ASSERT(CountLeadingZeroes32(0x00008000) == 16); + MOZ_RELEASE_ASSERT(CountLeadingZeroes32(0x00004000) == 17); + MOZ_RELEASE_ASSERT(CountLeadingZeroes32(0x00000080) == 24); + MOZ_RELEASE_ASSERT(CountLeadingZeroes32(0x00000040) == 25); + MOZ_RELEASE_ASSERT(CountLeadingZeroes32(0x00000001) == 31); +} + +static void +TestLeadingZeroes64() +{ + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0xF000F0F010000000) == 0); + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0x70F080F000000001) == 1); + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0x30F0F0F000100000) == 2); + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0x10F0F05000000100) == 3); + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0x0080000000000001) == 8); + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0x0040000010001000) == 9); + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0x000080F010000000) == 16); + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0x000040F010000000) == 17); + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0x0000008000100100) == 24); + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0x0000004100010010) == 25); + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0x0000000080100100) == 32); + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0x0000000041001010) == 33); + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0x0000000000800100) == 40); + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0x0000000000411010) == 41); + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0x0000000000008001) == 48); + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0x0000000000004010) == 49); + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0x0000000000000081) == 56); + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0x0000000000000040) == 57); + MOZ_RELEASE_ASSERT(CountLeadingZeroes64(0x0000000000000001) == 63); +} + +static void +TestTrailingZeroes32() +{ + MOZ_RELEASE_ASSERT(CountTrailingZeroes32(0x0100FFFF) == 0); + MOZ_RELEASE_ASSERT(CountTrailingZeroes32(0x7000FFFE) == 1); + MOZ_RELEASE_ASSERT(CountTrailingZeroes32(0x0080FFFC) == 2); + MOZ_RELEASE_ASSERT(CountTrailingZeroes32(0x0080FFF8) == 3); + MOZ_RELEASE_ASSERT(CountTrailingZeroes32(0x010FFF00) == 8); + MOZ_RELEASE_ASSERT(CountTrailingZeroes32(0x7000FE00) == 9); + MOZ_RELEASE_ASSERT(CountTrailingZeroes32(0x10CF0000) == 16); + MOZ_RELEASE_ASSERT(CountTrailingZeroes32(0x0BDE0000) == 17); + MOZ_RELEASE_ASSERT(CountTrailingZeroes32(0x0F000000) == 24); + MOZ_RELEASE_ASSERT(CountTrailingZeroes32(0xDE000000) == 25); + MOZ_RELEASE_ASSERT(CountTrailingZeroes32(0x80000000) == 31); +} + +static void +TestTrailingZeroes64() +{ + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0x000100000F0F0F0F) == 0); + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0x070000000F0F0F0E) == 1); + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0x000008000F0F0F0C) == 2); + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0x000008000F0F0F08) == 3); + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0xC001000F0F0F0F00) == 8); + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0x0200000F0F0F0E00) == 9); + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0xB0C10F0FEFDF0000) == 16); + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0x0AAA00F0FF0E0000) == 17); + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0xD010F0FEDF000000) == 24); + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0x7AAF0CF0BE000000) == 25); + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0x20F0A5D100000000) == 32); + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0x489BF0B200000000) == 33); + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0xE0F0D10000000000) == 40); + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0x97F0B20000000000) == 41); + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0x2C07000000000000) == 48); + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0x1FBA000000000000) == 49); + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0x0100000000000000) == 56); + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0x0200000000000000) == 57); + MOZ_RELEASE_ASSERT(CountTrailingZeroes64(0x8000000000000000) == 63); +} + +int +main() +{ + TestLeadingZeroes32(); + TestLeadingZeroes64(); + TestTrailingZeroes32(); + TestTrailingZeroes64(); + return 0; +} diff --git a/mfbt/tests/TestEndian.cpp b/mfbt/tests/TestEndian.cpp new file mode 100644 index 000000000..1fb8ac98f --- /dev/null +++ b/mfbt/tests/TestEndian.cpp @@ -0,0 +1,472 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/EndianUtils.h" + +#include <stddef.h> + +using mozilla::BigEndian; +using mozilla::LittleEndian; +using mozilla::NativeEndian; + +template<typename T> +void +TestSingleSwap(T aValue, T aSwappedValue) +{ +#if MOZ_LITTLE_ENDIAN + MOZ_RELEASE_ASSERT(NativeEndian::swapToBigEndian(aValue) == aSwappedValue); + MOZ_RELEASE_ASSERT(NativeEndian::swapFromBigEndian(aValue) == aSwappedValue); + MOZ_RELEASE_ASSERT(NativeEndian::swapToNetworkOrder(aValue) == aSwappedValue); + MOZ_RELEASE_ASSERT(NativeEndian::swapFromNetworkOrder(aValue) == + aSwappedValue); +#else + MOZ_RELEASE_ASSERT(NativeEndian::swapToLittleEndian(aValue) == aSwappedValue); + MOZ_RELEASE_ASSERT(NativeEndian::swapFromLittleEndian(aValue) == + aSwappedValue); +#endif +} + +template<typename T> +void +TestSingleNoSwap(T aValue, T aUnswappedValue) +{ +#if MOZ_LITTLE_ENDIAN + MOZ_RELEASE_ASSERT(NativeEndian::swapToLittleEndian(aValue) == + aUnswappedValue); + MOZ_RELEASE_ASSERT(NativeEndian::swapFromLittleEndian(aValue) == + aUnswappedValue); +#else + MOZ_RELEASE_ASSERT(NativeEndian::swapToBigEndian(aValue) == aUnswappedValue); + MOZ_RELEASE_ASSERT(NativeEndian::swapFromBigEndian(aValue) == aUnswappedValue); + MOZ_RELEASE_ASSERT(NativeEndian::swapToNetworkOrder(aValue) == + aUnswappedValue); + MOZ_RELEASE_ASSERT(NativeEndian::swapFromNetworkOrder(aValue) == + aUnswappedValue); +#endif +} + +// EndianUtils.h functions are declared as protected in a base class and +// then re-exported as public in public derived classes. The +// standardese around explicit instantiation of templates is not clear +// in such cases. Provide these wrappers to make things more explicit. +// For your own enlightenment, you may wish to peruse: +// http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56152 and subsequently +// http://j.mp/XosS6S . +#define WRAP_COPYTO(NAME) \ + template<typename T> \ + void \ + NAME(void* aDst, const T* aSrc, size_t aCount) \ + { \ + NativeEndian::NAME<T>(aDst, aSrc, aCount); \ + } + +WRAP_COPYTO(copyAndSwapToLittleEndian) +WRAP_COPYTO(copyAndSwapToBigEndian) +WRAP_COPYTO(copyAndSwapToNetworkOrder) + +#define WRAP_COPYFROM(NAME) \ + template<typename T> \ + void \ + NAME(T* aDst, const void* aSrc, size_t aCount) \ + { \ + NativeEndian::NAME<T>(aDst, aSrc, aCount); \ + } + +WRAP_COPYFROM(copyAndSwapFromLittleEndian) +WRAP_COPYFROM(copyAndSwapFromBigEndian) +WRAP_COPYFROM(copyAndSwapFromNetworkOrder) + +#define WRAP_IN_PLACE(NAME) \ + template<typename T> \ + void \ + NAME(T* aP, size_t aCount) \ + { \ + NativeEndian::NAME<T>(aP, aCount); \ + } +WRAP_IN_PLACE(swapToLittleEndianInPlace) +WRAP_IN_PLACE(swapFromLittleEndianInPlace) +WRAP_IN_PLACE(swapToBigEndianInPlace) +WRAP_IN_PLACE(swapFromBigEndianInPlace) +WRAP_IN_PLACE(swapToNetworkOrderInPlace) +WRAP_IN_PLACE(swapFromNetworkOrderInPlace) + +enum SwapExpectation +{ + Swap, + NoSwap +}; + +template<typename T, size_t Count> +void +TestBulkSwapToSub(enum SwapExpectation aExpectSwap, + const T (&aValues)[Count], + void (*aSwapperFunc)(void*, const T*, size_t), + T (*aReaderFunc)(const void*)) +{ + const size_t arraySize = 2 * Count; + const size_t bufferSize = arraySize * sizeof(T); + static uint8_t buffer[bufferSize]; + const uint8_t fillValue = 0xa5; + static uint8_t checkBuffer[bufferSize]; + + MOZ_RELEASE_ASSERT(bufferSize > 2 * sizeof(T)); + + memset(checkBuffer, fillValue, bufferSize); + + for (size_t startPosition = 0; startPosition < sizeof(T); ++startPosition) { + for (size_t nValues = 0; nValues < Count; ++nValues) { + memset(buffer, fillValue, bufferSize); + aSwapperFunc(buffer + startPosition, aValues, nValues); + + MOZ_RELEASE_ASSERT(memcmp(buffer, checkBuffer, startPosition) == 0); + size_t valuesEndPosition = startPosition + sizeof(T) * nValues; + MOZ_RELEASE_ASSERT(memcmp(buffer + valuesEndPosition, + checkBuffer + valuesEndPosition, + bufferSize - valuesEndPosition) == 0); + if (aExpectSwap == NoSwap) { + MOZ_RELEASE_ASSERT(memcmp(buffer + startPosition, aValues, + nValues * sizeof(T)) == 0); + } + for (size_t i = 0; i < nValues; ++i) { + MOZ_RELEASE_ASSERT( + aReaderFunc(buffer + startPosition + sizeof(T) * i) == aValues[i]); + } + } + } +} + +template<typename T, size_t Count> +void +TestBulkSwapFromSub(enum SwapExpectation aExpectSwap, + const T (&aValues)[Count], + void (*aSwapperFunc)(T*, const void*, size_t), + T (*aReaderFunc)(const void*)) +{ + const size_t arraySize = 2 * Count; + const size_t bufferSize = arraySize * sizeof(T); + static T buffer[arraySize]; + const uint8_t fillValue = 0xa5; + static T checkBuffer[arraySize]; + + memset(checkBuffer, fillValue, bufferSize); + + for (size_t startPosition = 0; startPosition < Count; ++startPosition) { + for (size_t nValues = 0; nValues < (Count - startPosition); ++nValues) { + memset(buffer, fillValue, bufferSize); + aSwapperFunc(buffer + startPosition, aValues, nValues); + + MOZ_RELEASE_ASSERT( + memcmp(buffer, checkBuffer, startPosition * sizeof(T)) == 0); + size_t valuesEndPosition = startPosition + nValues; + MOZ_RELEASE_ASSERT(memcmp(buffer + valuesEndPosition, + checkBuffer + valuesEndPosition, + (arraySize - valuesEndPosition) * sizeof(T)) == 0); + if (aExpectSwap == NoSwap) { + MOZ_RELEASE_ASSERT(memcmp(buffer + startPosition, aValues, + nValues * sizeof(T)) == 0); + } + for (size_t i = 0; i < nValues; ++i) { + MOZ_RELEASE_ASSERT(aReaderFunc(buffer + startPosition + i) == aValues[i]); + } + } + } +} + + +template<typename T, size_t Count> +void +TestBulkInPlaceSub(enum SwapExpectation aExpectSwap, + const T (&aValues)[Count], + void (*aSwapperFunc)(T*, size_t), + T (*aReaderFunc)(const void*)) +{ + const size_t bufferCount = 4 * Count; + const size_t bufferSize = bufferCount * sizeof(T); + static T buffer[bufferCount]; + const T fillValue = 0xa5; + static T checkBuffer[bufferCount]; + + MOZ_RELEASE_ASSERT(bufferSize > 2 * sizeof(T)); + + memset(checkBuffer, fillValue, bufferSize); + + for (size_t startPosition = 0; startPosition < Count; ++startPosition) { + for (size_t nValues = 0; nValues < Count; ++nValues) { + memset(buffer, fillValue, bufferSize); + memcpy(buffer + startPosition, aValues, nValues * sizeof(T)); + aSwapperFunc(buffer + startPosition, nValues); + + MOZ_RELEASE_ASSERT( + memcmp(buffer, checkBuffer, startPosition * sizeof(T)) == 0); + size_t valuesEndPosition = startPosition + nValues; + MOZ_RELEASE_ASSERT(memcmp(buffer + valuesEndPosition, + checkBuffer + valuesEndPosition, + bufferSize - valuesEndPosition * sizeof(T)) == 0); + if (aExpectSwap == NoSwap) { + MOZ_RELEASE_ASSERT(memcmp(buffer + startPosition, aValues, + nValues * sizeof(T)) == 0); + } + for (size_t i = 0; i < nValues; ++i) { + MOZ_RELEASE_ASSERT(aReaderFunc(buffer + startPosition + i) == aValues[i]); + } + } + } +} + +template<typename T> +struct Reader +{ +}; + +#define SPECIALIZE_READER(TYPE, READ_FUNC) \ + template<> \ + struct Reader<TYPE> \ + { \ + static TYPE readLE(const void* aP) { return LittleEndian::READ_FUNC(aP); }\ + static TYPE readBE(const void* aP) { return BigEndian::READ_FUNC(aP); } \ + }; + +SPECIALIZE_READER(uint16_t, readUint16) +SPECIALIZE_READER(uint32_t, readUint32) +SPECIALIZE_READER(uint64_t, readUint64) +SPECIALIZE_READER(int16_t, readInt16) +SPECIALIZE_READER(int32_t, readInt32) +SPECIALIZE_READER(int64_t, readInt64) + +template<typename T, size_t Count> +void +TestBulkSwap(const T (&aBytes)[Count]) +{ +#if MOZ_LITTLE_ENDIAN + TestBulkSwapToSub(Swap, aBytes, copyAndSwapToBigEndian<T>, + Reader<T>::readBE); + TestBulkSwapFromSub(Swap, aBytes, copyAndSwapFromBigEndian<T>, + Reader<T>::readBE); + TestBulkSwapToSub(Swap, aBytes, copyAndSwapToNetworkOrder<T>, + Reader<T>::readBE); + TestBulkSwapFromSub(Swap, aBytes, copyAndSwapFromNetworkOrder<T>, + Reader<T>::readBE); +#else + TestBulkSwapToSub(Swap, aBytes, copyAndSwapToLittleEndian<T>, + Reader<T>::readLE); + TestBulkSwapFromSub(Swap, aBytes, copyAndSwapFromLittleEndian<T>, + Reader<T>::readLE); +#endif +} + +template<typename T, size_t Count> +void +TestBulkNoSwap(const T (&aBytes)[Count]) +{ +#if MOZ_LITTLE_ENDIAN + TestBulkSwapToSub(NoSwap, aBytes, copyAndSwapToLittleEndian<T>, + Reader<T>::readLE); + TestBulkSwapFromSub(NoSwap, aBytes, copyAndSwapFromLittleEndian<T>, + Reader<T>::readLE); +#else + TestBulkSwapToSub(NoSwap, aBytes, copyAndSwapToBigEndian<T>, + Reader<T>::readBE); + TestBulkSwapFromSub(NoSwap, aBytes, copyAndSwapFromBigEndian<T>, + Reader<T>::readBE); + TestBulkSwapToSub(NoSwap, aBytes, copyAndSwapToNetworkOrder<T>, + Reader<T>::readBE); + TestBulkSwapFromSub(NoSwap, aBytes, copyAndSwapFromNetworkOrder<T>, + Reader<T>::readBE); +#endif +} + +template<typename T, size_t Count> +void +TestBulkInPlaceSwap(const T (&aBytes)[Count]) +{ +#if MOZ_LITTLE_ENDIAN + TestBulkInPlaceSub(Swap, aBytes, swapToBigEndianInPlace<T>, + Reader<T>::readBE); + TestBulkInPlaceSub(Swap, aBytes, swapFromBigEndianInPlace<T>, + Reader<T>::readBE); + TestBulkInPlaceSub(Swap, aBytes, swapToNetworkOrderInPlace<T>, + Reader<T>::readBE); + TestBulkInPlaceSub(Swap, aBytes, swapFromNetworkOrderInPlace<T>, + Reader<T>::readBE); +#else + TestBulkInPlaceSub(Swap, aBytes, swapToLittleEndianInPlace<T>, + Reader<T>::readLE); + TestBulkInPlaceSub(Swap, aBytes, swapFromLittleEndianInPlace<T>, + Reader<T>::readLE); +#endif +} + +template<typename T, size_t Count> +void +TestBulkInPlaceNoSwap(const T (&aBytes)[Count]) +{ +#if MOZ_LITTLE_ENDIAN + TestBulkInPlaceSub(NoSwap, aBytes, swapToLittleEndianInPlace<T>, + Reader<T>::readLE); + TestBulkInPlaceSub(NoSwap, aBytes, swapFromLittleEndianInPlace<T>, + Reader<T>::readLE); +#else + TestBulkInPlaceSub(NoSwap, aBytes, swapToBigEndianInPlace<T>, + Reader<T>::readBE); + TestBulkInPlaceSub(NoSwap, aBytes, swapFromBigEndianInPlace<T>, + Reader<T>::readBE); + TestBulkInPlaceSub(NoSwap, aBytes, swapToNetworkOrderInPlace<T>, + Reader<T>::readBE); + TestBulkInPlaceSub(NoSwap, aBytes, swapFromNetworkOrderInPlace<T>, + Reader<T>::readBE); +#endif +} + +int +main() +{ + static const uint8_t unsigned_bytes[16] = { + 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, + 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8 + }; + static const int8_t signed_bytes[16] = { + -0x0f, -0x0e, -0x0d, -0x0c, -0x0b, -0x0a, -0x09, -0x08, + -0x0f, -0x0e, -0x0d, -0x0c, -0x0b, -0x0a, -0x09, -0x08 + }; + static const uint16_t uint16_values[8] = { + 0x102, 0x304, 0x506, 0x708, 0x102, 0x304, 0x506, 0x708 + }; + static const int16_t int16_values[8] = { + int16_t(0xf1f2), int16_t(0xf3f4), int16_t(0xf5f6), int16_t(0xf7f8), + int16_t(0xf1f2), int16_t(0xf3f4), int16_t(0xf5f6), int16_t(0xf7f8) + }; + static const uint32_t uint32_values[4] = { + 0x1020304, 0x5060708, 0x1020304, 0x5060708 + }; + static const int32_t int32_values[4] = { + int32_t(0xf1f2f3f4), int32_t(0xf5f6f7f8), + int32_t(0xf1f2f3f4), int32_t(0xf5f6f7f8) + }; + static const uint64_t uint64_values[2] = { + 0x102030405060708, 0x102030405060708 + }; + static const int64_t int64_values[2] = { + int64_t(0xf1f2f3f4f5f6f7f8), int64_t(0xf1f2f3f4f5f6f7f8) + }; + uint8_t buffer[8]; + + MOZ_RELEASE_ASSERT(LittleEndian::readUint16(&unsigned_bytes[0]) == 0x201); + MOZ_RELEASE_ASSERT(BigEndian::readUint16(&unsigned_bytes[0]) == 0x102); + + MOZ_RELEASE_ASSERT( + LittleEndian::readUint32(&unsigned_bytes[0]) == 0x4030201U); + MOZ_RELEASE_ASSERT( + BigEndian::readUint32(&unsigned_bytes[0]) == 0x1020304U); + + MOZ_RELEASE_ASSERT( + LittleEndian::readUint64(&unsigned_bytes[0]) == 0x807060504030201ULL); + MOZ_RELEASE_ASSERT( + BigEndian::readUint64(&unsigned_bytes[0]) == 0x102030405060708ULL); + + LittleEndian::writeUint16(&buffer[0], 0x201); + MOZ_RELEASE_ASSERT( + memcmp(&unsigned_bytes[0], &buffer[0], sizeof(uint16_t)) == 0); + BigEndian::writeUint16(&buffer[0], 0x102); + MOZ_RELEASE_ASSERT( + memcmp(&unsigned_bytes[0], &buffer[0], sizeof(uint16_t)) == 0); + + LittleEndian::writeUint32(&buffer[0], 0x4030201U); + MOZ_RELEASE_ASSERT( + memcmp(&unsigned_bytes[0], &buffer[0], sizeof(uint32_t)) == 0); + BigEndian::writeUint32(&buffer[0], 0x1020304U); + MOZ_RELEASE_ASSERT( + memcmp(&unsigned_bytes[0], &buffer[0], sizeof(uint32_t)) == 0); + + LittleEndian::writeUint64(&buffer[0], 0x807060504030201ULL); + MOZ_RELEASE_ASSERT( + memcmp(&unsigned_bytes[0], &buffer[0], sizeof(uint64_t)) == 0); + BigEndian::writeUint64(&buffer[0], 0x102030405060708ULL); + MOZ_RELEASE_ASSERT( + memcmp(&unsigned_bytes[0], &buffer[0], sizeof(uint64_t)) == 0); + + MOZ_RELEASE_ASSERT( + LittleEndian::readInt16(&signed_bytes[0]) == int16_t(0xf2f1)); + MOZ_RELEASE_ASSERT( + BigEndian::readInt16(&signed_bytes[0]) == int16_t(0xf1f2)); + + MOZ_RELEASE_ASSERT( + LittleEndian::readInt32(&signed_bytes[0]) == int32_t(0xf4f3f2f1)); + MOZ_RELEASE_ASSERT( + BigEndian::readInt32(&signed_bytes[0]) == int32_t(0xf1f2f3f4)); + + MOZ_RELEASE_ASSERT( + LittleEndian::readInt64(&signed_bytes[0]) == int64_t(0xf8f7f6f5f4f3f2f1LL)); + MOZ_RELEASE_ASSERT( + BigEndian::readInt64(&signed_bytes[0]) == int64_t(0xf1f2f3f4f5f6f7f8LL)); + + LittleEndian::writeInt16(&buffer[0], int16_t(0xf2f1)); + MOZ_RELEASE_ASSERT( + memcmp(&signed_bytes[0], &buffer[0], sizeof(int16_t)) == 0); + BigEndian::writeInt16(&buffer[0], int16_t(0xf1f2)); + MOZ_RELEASE_ASSERT( + memcmp(&signed_bytes[0], &buffer[0], sizeof(int16_t)) == 0); + + LittleEndian::writeInt32(&buffer[0], 0xf4f3f2f1); + MOZ_RELEASE_ASSERT( + memcmp(&signed_bytes[0], &buffer[0], sizeof(int32_t)) == 0); + BigEndian::writeInt32(&buffer[0], 0xf1f2f3f4); + MOZ_RELEASE_ASSERT( + memcmp(&signed_bytes[0], &buffer[0], sizeof(int32_t)) == 0); + + LittleEndian::writeInt64(&buffer[0], 0xf8f7f6f5f4f3f2f1LL); + MOZ_RELEASE_ASSERT( + memcmp(&signed_bytes[0], &buffer[0], sizeof(int64_t)) == 0); + BigEndian::writeInt64(&buffer[0], 0xf1f2f3f4f5f6f7f8LL); + MOZ_RELEASE_ASSERT( + memcmp(&signed_bytes[0], &buffer[0], sizeof(int64_t)) == 0); + + TestSingleSwap(uint16_t(0xf2f1), uint16_t(0xf1f2)); + TestSingleSwap(uint32_t(0xf4f3f2f1), uint32_t(0xf1f2f3f4)); + TestSingleSwap(uint64_t(0xf8f7f6f5f4f3f2f1), uint64_t(0xf1f2f3f4f5f6f7f8)); + + TestSingleSwap(int16_t(0xf2f1), int16_t(0xf1f2)); + TestSingleSwap(int32_t(0xf4f3f2f1), int32_t(0xf1f2f3f4)); + TestSingleSwap(int64_t(0xf8f7f6f5f4f3f2f1), int64_t(0xf1f2f3f4f5f6f7f8)); + + TestSingleNoSwap(uint16_t(0xf2f1), uint16_t(0xf2f1)); + TestSingleNoSwap(uint32_t(0xf4f3f2f1), uint32_t(0xf4f3f2f1)); + TestSingleNoSwap(uint64_t(0xf8f7f6f5f4f3f2f1), uint64_t(0xf8f7f6f5f4f3f2f1)); + + TestSingleNoSwap(int16_t(0xf2f1), int16_t(0xf2f1)); + TestSingleNoSwap(int32_t(0xf4f3f2f1), int32_t(0xf4f3f2f1)); + TestSingleNoSwap(int64_t(0xf8f7f6f5f4f3f2f1), int64_t(0xf8f7f6f5f4f3f2f1)); + + TestBulkSwap(uint16_values); + TestBulkSwap(int16_values); + TestBulkSwap(uint32_values); + TestBulkSwap(int32_values); + TestBulkSwap(uint64_values); + TestBulkSwap(int64_values); + + TestBulkNoSwap(uint16_values); + TestBulkNoSwap(int16_values); + TestBulkNoSwap(uint32_values); + TestBulkNoSwap(int32_values); + TestBulkNoSwap(uint64_values); + TestBulkNoSwap(int64_values); + + TestBulkInPlaceSwap(uint16_values); + TestBulkInPlaceSwap(int16_values); + TestBulkInPlaceSwap(uint32_values); + TestBulkInPlaceSwap(int32_values); + TestBulkInPlaceSwap(uint64_values); + TestBulkInPlaceSwap(int64_values); + + TestBulkInPlaceNoSwap(uint16_values); + TestBulkInPlaceNoSwap(int16_values); + TestBulkInPlaceNoSwap(uint32_values); + TestBulkInPlaceNoSwap(int32_values); + TestBulkInPlaceNoSwap(uint64_values); + TestBulkInPlaceNoSwap(int64_values); + + return 0; +} diff --git a/mfbt/tests/TestEnumSet.cpp b/mfbt/tests/TestEnumSet.cpp new file mode 100644 index 000000000..801295fd6 --- /dev/null +++ b/mfbt/tests/TestEnumSet.cpp @@ -0,0 +1,289 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/EnumSet.h" +#include "mozilla/Vector.h" + +using namespace mozilla; + +enum SeaBird +{ + PENGUIN, + ALBATROSS, + FULMAR, + PRION, + SHEARWATER, + GADFLY_PETREL, + TRUE_PETREL, + DIVING_PETREL, + STORM_PETREL, + PELICAN, + GANNET, + BOOBY, + CORMORANT, + FRIGATEBIRD, + TROPICBIRD, + SKUA, + GULL, + TERN, + SKIMMER, + AUK +}; + +class EnumSetSuite +{ +public: + EnumSetSuite() + : mAlcidae() + , mDiomedeidae(ALBATROSS) + , mPetrelProcellariidae(GADFLY_PETREL, TRUE_PETREL) + , mNonPetrelProcellariidae(FULMAR, PRION, SHEARWATER) + , mPetrels(GADFLY_PETREL, TRUE_PETREL, DIVING_PETREL, STORM_PETREL) + { } + + void runTests() + { + testSize(); + testContains(); + testAddTo(); + testAdd(); + testAddAll(); + testUnion(); + testRemoveFrom(); + testRemove(); + testRemoveAllFrom(); + testRemoveAll(); + testIntersect(); + testInsersection(); + testEquality(); + testDuplicates(); + testIteration(); + testInitializerListConstuctor(); + } + +private: + void testSize() + { + MOZ_RELEASE_ASSERT(mAlcidae.size() == 0); + MOZ_RELEASE_ASSERT(mDiomedeidae.size() == 1); + MOZ_RELEASE_ASSERT(mPetrelProcellariidae.size() == 2); + MOZ_RELEASE_ASSERT(mNonPetrelProcellariidae.size() == 3); + MOZ_RELEASE_ASSERT(mPetrels.size() == 4); + } + + void testContains() + { + MOZ_RELEASE_ASSERT(!mPetrels.contains(PENGUIN)); + MOZ_RELEASE_ASSERT(!mPetrels.contains(ALBATROSS)); + MOZ_RELEASE_ASSERT(!mPetrels.contains(FULMAR)); + MOZ_RELEASE_ASSERT(!mPetrels.contains(PRION)); + MOZ_RELEASE_ASSERT(!mPetrels.contains(SHEARWATER)); + MOZ_RELEASE_ASSERT(mPetrels.contains(GADFLY_PETREL)); + MOZ_RELEASE_ASSERT(mPetrels.contains(TRUE_PETREL)); + MOZ_RELEASE_ASSERT(mPetrels.contains(DIVING_PETREL)); + MOZ_RELEASE_ASSERT(mPetrels.contains(STORM_PETREL)); + MOZ_RELEASE_ASSERT(!mPetrels.contains(PELICAN)); + MOZ_RELEASE_ASSERT(!mPetrels.contains(GANNET)); + MOZ_RELEASE_ASSERT(!mPetrels.contains(BOOBY)); + MOZ_RELEASE_ASSERT(!mPetrels.contains(CORMORANT)); + MOZ_RELEASE_ASSERT(!mPetrels.contains(FRIGATEBIRD)); + MOZ_RELEASE_ASSERT(!mPetrels.contains(TROPICBIRD)); + MOZ_RELEASE_ASSERT(!mPetrels.contains(SKUA)); + MOZ_RELEASE_ASSERT(!mPetrels.contains(GULL)); + MOZ_RELEASE_ASSERT(!mPetrels.contains(TERN)); + MOZ_RELEASE_ASSERT(!mPetrels.contains(SKIMMER)); + MOZ_RELEASE_ASSERT(!mPetrels.contains(AUK)); + } + + void testCopy() + { + EnumSet<SeaBird> likes = mPetrels; + likes -= TRUE_PETREL; + MOZ_RELEASE_ASSERT(mPetrels.size() == 4); + MOZ_RELEASE_ASSERT(mPetrels.contains(TRUE_PETREL)); + + MOZ_RELEASE_ASSERT(likes.size() == 3); + MOZ_RELEASE_ASSERT(likes.contains(GADFLY_PETREL)); + MOZ_RELEASE_ASSERT(likes.contains(DIVING_PETREL)); + MOZ_RELEASE_ASSERT(likes.contains(STORM_PETREL)); + } + + void testAddTo() + { + EnumSet<SeaBird> seen = mPetrels; + seen += CORMORANT; + seen += TRUE_PETREL; + MOZ_RELEASE_ASSERT(mPetrels.size() == 4); + MOZ_RELEASE_ASSERT(!mPetrels.contains(CORMORANT)); + MOZ_RELEASE_ASSERT(seen.size() == 5); + MOZ_RELEASE_ASSERT(seen.contains(GADFLY_PETREL)); + MOZ_RELEASE_ASSERT(seen.contains(TRUE_PETREL)); + MOZ_RELEASE_ASSERT(seen.contains(DIVING_PETREL)); + MOZ_RELEASE_ASSERT(seen.contains(STORM_PETREL)); + MOZ_RELEASE_ASSERT(seen.contains(CORMORANT)); + } + + void testAdd() + { + EnumSet<SeaBird> seen = mPetrels + CORMORANT + STORM_PETREL; + MOZ_RELEASE_ASSERT(mPetrels.size() == 4); + MOZ_RELEASE_ASSERT(!mPetrels.contains(CORMORANT)); + MOZ_RELEASE_ASSERT(seen.size() == 5); + MOZ_RELEASE_ASSERT(seen.contains(GADFLY_PETREL)); + MOZ_RELEASE_ASSERT(seen.contains(TRUE_PETREL)); + MOZ_RELEASE_ASSERT(seen.contains(DIVING_PETREL)); + MOZ_RELEASE_ASSERT(seen.contains(STORM_PETREL)); + MOZ_RELEASE_ASSERT(seen.contains(CORMORANT)); + } + + void testAddAll() + { + EnumSet<SeaBird> procellariidae; + procellariidae += mPetrelProcellariidae; + procellariidae += mNonPetrelProcellariidae; + MOZ_RELEASE_ASSERT(procellariidae.size() == 5); + + // Both procellariidae and mPetrels include GADFLY_PERTEL and TRUE_PETREL + EnumSet<SeaBird> procellariiformes; + procellariiformes += mDiomedeidae; + procellariiformes += procellariidae; + procellariiformes += mPetrels; + MOZ_RELEASE_ASSERT(procellariiformes.size() == 8); + } + + void testUnion() + { + EnumSet<SeaBird> procellariidae = mPetrelProcellariidae + + mNonPetrelProcellariidae; + MOZ_RELEASE_ASSERT(procellariidae.size() == 5); + + // Both procellariidae and mPetrels include GADFLY_PETREL and TRUE_PETREL + EnumSet<SeaBird> procellariiformes = mDiomedeidae + procellariidae + + mPetrels; + MOZ_RELEASE_ASSERT(procellariiformes.size() == 8); + } + + void testRemoveFrom() + { + EnumSet<SeaBird> likes = mPetrels; + likes -= TRUE_PETREL; + likes -= DIVING_PETREL; + MOZ_RELEASE_ASSERT(likes.size() == 2); + MOZ_RELEASE_ASSERT(likes.contains(GADFLY_PETREL)); + MOZ_RELEASE_ASSERT(likes.contains(STORM_PETREL)); + } + + void testRemove() + { + EnumSet<SeaBird> likes = mPetrels - TRUE_PETREL - DIVING_PETREL; + MOZ_RELEASE_ASSERT(likes.size() == 2); + MOZ_RELEASE_ASSERT(likes.contains(GADFLY_PETREL)); + MOZ_RELEASE_ASSERT(likes.contains(STORM_PETREL)); + } + + void testRemoveAllFrom() + { + EnumSet<SeaBird> likes = mPetrels; + likes -= mPetrelProcellariidae; + MOZ_RELEASE_ASSERT(likes.size() == 2); + MOZ_RELEASE_ASSERT(likes.contains(DIVING_PETREL)); + MOZ_RELEASE_ASSERT(likes.contains(STORM_PETREL)); + } + + void testRemoveAll() + { + EnumSet<SeaBird> likes = mPetrels - mPetrelProcellariidae; + MOZ_RELEASE_ASSERT(likes.size() == 2); + MOZ_RELEASE_ASSERT(likes.contains(DIVING_PETREL)); + MOZ_RELEASE_ASSERT(likes.contains(STORM_PETREL)); + } + + void testIntersect() + { + EnumSet<SeaBird> likes = mPetrels; + likes &= mPetrelProcellariidae; + MOZ_RELEASE_ASSERT(likes.size() == 2); + MOZ_RELEASE_ASSERT(likes.contains(GADFLY_PETREL)); + MOZ_RELEASE_ASSERT(likes.contains(TRUE_PETREL)); + } + + void testInsersection() + { + EnumSet<SeaBird> likes = mPetrels & mPetrelProcellariidae; + MOZ_RELEASE_ASSERT(likes.size() == 2); + MOZ_RELEASE_ASSERT(likes.contains(GADFLY_PETREL)); + MOZ_RELEASE_ASSERT(likes.contains(TRUE_PETREL)); + } + + void testEquality() + { + EnumSet<SeaBird> likes = mPetrels & mPetrelProcellariidae; + MOZ_RELEASE_ASSERT(likes == EnumSet<SeaBird>(GADFLY_PETREL, + TRUE_PETREL)); + } + + void testDuplicates() + { + EnumSet<SeaBird> likes = mPetrels; + likes += GADFLY_PETREL; + likes += TRUE_PETREL; + likes += DIVING_PETREL; + likes += STORM_PETREL; + MOZ_RELEASE_ASSERT(likes.size() == 4); + MOZ_RELEASE_ASSERT(likes == mPetrels); + } + + void testIteration() + { + EnumSet<SeaBird> birds; + Vector<SeaBird> vec; + + for (auto bird : birds) { + MOZ_RELEASE_ASSERT(vec.append(bird)); + } + MOZ_RELEASE_ASSERT(vec.length() == 0); + + birds += DIVING_PETREL; + birds += GADFLY_PETREL; + birds += STORM_PETREL; + birds += TRUE_PETREL; + for (auto bird : birds) { + MOZ_RELEASE_ASSERT(vec.append(bird)); + } + + MOZ_RELEASE_ASSERT(vec.length() == 4); + MOZ_RELEASE_ASSERT(vec[0] == GADFLY_PETREL); + MOZ_RELEASE_ASSERT(vec[1] == TRUE_PETREL); + MOZ_RELEASE_ASSERT(vec[2] == DIVING_PETREL); + MOZ_RELEASE_ASSERT(vec[3] == STORM_PETREL); + } + + void testInitializerListConstuctor() + { + EnumSet<SeaBird> empty {}; + MOZ_RELEASE_ASSERT(empty.size() == 0); + + EnumSet<SeaBird> someBirds { SKIMMER, GULL, BOOBY }; + MOZ_RELEASE_ASSERT(someBirds.size() == 3); + MOZ_RELEASE_ASSERT(someBirds.contains(SKIMMER)); + MOZ_RELEASE_ASSERT(someBirds.contains(GULL)); + MOZ_RELEASE_ASSERT(someBirds.contains(BOOBY)); + } + + EnumSet<SeaBird> mAlcidae; + EnumSet<SeaBird> mDiomedeidae; + EnumSet<SeaBird> mPetrelProcellariidae; + EnumSet<SeaBird> mNonPetrelProcellariidae; + EnumSet<SeaBird> mPetrels; +}; + +int +main() +{ + EnumSetSuite suite; + suite.runTests(); + return 0; +} diff --git a/mfbt/tests/TestEnumTypeTraits.cpp b/mfbt/tests/TestEnumTypeTraits.cpp new file mode 100644 index 000000000..879d40526 --- /dev/null +++ b/mfbt/tests/TestEnumTypeTraits.cpp @@ -0,0 +1,136 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/IntegerTypeTraits.h" +#include "mozilla/EnumTypeTraits.h" + +using namespace mozilla; + +/* Feature check for EnumTypeFitsWithin. */ + +#define MAKE_FIXED_EMUM_FOR_TYPE(IntType) \ + enum FixedEnumFor_##IntType : IntType { \ + A_##IntType, \ + B_##IntType, \ + C_##IntType, \ + }; + +template<typename EnumType, typename IntType> +static void +TestShouldFit() +{ + static_assert(EnumTypeFitsWithin<EnumType, IntType>::value, + "Should fit within exact/promoted integral type"); +} + +template<typename EnumType, typename IntType> +static void +TestShouldNotFit() +{ + static_assert(!EnumTypeFitsWithin<EnumType, IntType>::value, + "Should not fit within"); +} + +int +main() +{ + // check for int8_t + MAKE_FIXED_EMUM_FOR_TYPE(int8_t); + TestShouldFit<FixedEnumFor_int8_t, int8_t>(); + TestShouldFit<FixedEnumFor_int8_t, int16_t>(); + TestShouldFit<FixedEnumFor_int8_t, int32_t>(); + TestShouldFit<FixedEnumFor_int8_t, int64_t>(); + + TestShouldNotFit<FixedEnumFor_int8_t, uint8_t>(); + TestShouldNotFit<FixedEnumFor_int8_t, uint16_t>(); + TestShouldNotFit<FixedEnumFor_int8_t, uint32_t>(); + TestShouldNotFit<FixedEnumFor_int8_t, uint64_t>(); + + // check for uint8_t + MAKE_FIXED_EMUM_FOR_TYPE(uint8_t); + TestShouldFit<FixedEnumFor_uint8_t, uint8_t>(); + TestShouldFit<FixedEnumFor_uint8_t, uint16_t>(); + TestShouldFit<FixedEnumFor_uint8_t, uint32_t>(); + TestShouldFit<FixedEnumFor_uint8_t, uint64_t>(); + + TestShouldNotFit<FixedEnumFor_uint8_t, int8_t>(); + TestShouldFit<FixedEnumFor_uint8_t, int16_t>(); + TestShouldFit<FixedEnumFor_uint8_t, int32_t>(); + TestShouldFit<FixedEnumFor_uint8_t, int64_t>(); + + // check for int16_t + MAKE_FIXED_EMUM_FOR_TYPE(int16_t); + TestShouldNotFit<FixedEnumFor_int16_t, int8_t>(); + TestShouldFit<FixedEnumFor_int16_t, int16_t>(); + TestShouldFit<FixedEnumFor_int16_t, int32_t>(); + TestShouldFit<FixedEnumFor_int16_t, int64_t>(); + + TestShouldNotFit<FixedEnumFor_int16_t, uint8_t>(); + TestShouldNotFit<FixedEnumFor_int16_t, uint16_t>(); + TestShouldNotFit<FixedEnumFor_int16_t, uint32_t>(); + TestShouldNotFit<FixedEnumFor_int16_t, uint64_t>(); + + // check for uint16_t + MAKE_FIXED_EMUM_FOR_TYPE(uint16_t); + TestShouldNotFit<FixedEnumFor_uint16_t, uint8_t>(); + TestShouldFit<FixedEnumFor_uint16_t, uint16_t>(); + TestShouldFit<FixedEnumFor_uint16_t, uint32_t>(); + TestShouldFit<FixedEnumFor_uint16_t, uint64_t>(); + + TestShouldNotFit<FixedEnumFor_uint16_t, int8_t>(); + TestShouldNotFit<FixedEnumFor_uint16_t, int16_t>(); + TestShouldFit<FixedEnumFor_uint16_t, int32_t>(); + TestShouldFit<FixedEnumFor_uint16_t, int64_t>(); + + // check for int32_t + MAKE_FIXED_EMUM_FOR_TYPE(int32_t); + TestShouldNotFit<FixedEnumFor_int32_t, int8_t>(); + TestShouldNotFit<FixedEnumFor_int32_t, int16_t>(); + TestShouldFit<FixedEnumFor_int32_t, int32_t>(); + TestShouldFit<FixedEnumFor_int32_t, int64_t>(); + + TestShouldNotFit<FixedEnumFor_int32_t, uint8_t>(); + TestShouldNotFit<FixedEnumFor_int32_t, uint16_t>(); + TestShouldNotFit<FixedEnumFor_int32_t, uint32_t>(); + TestShouldNotFit<FixedEnumFor_int32_t, uint64_t>(); + + // check for uint32_t + MAKE_FIXED_EMUM_FOR_TYPE(uint32_t); + TestShouldNotFit<FixedEnumFor_uint32_t, uint8_t>(); + TestShouldNotFit<FixedEnumFor_uint32_t, uint16_t>(); + TestShouldFit<FixedEnumFor_uint32_t, uint32_t>(); + TestShouldFit<FixedEnumFor_uint32_t, uint64_t>(); + + TestShouldNotFit<FixedEnumFor_uint32_t, int8_t>(); + TestShouldNotFit<FixedEnumFor_uint32_t, int16_t>(); + TestShouldNotFit<FixedEnumFor_uint32_t, int32_t>(); + TestShouldFit<FixedEnumFor_uint32_t, int64_t>(); + + // check for int64_t + MAKE_FIXED_EMUM_FOR_TYPE(int64_t); + TestShouldNotFit<FixedEnumFor_int64_t, int8_t>(); + TestShouldNotFit<FixedEnumFor_int64_t, int16_t>(); + TestShouldNotFit<FixedEnumFor_int64_t, int32_t>(); + TestShouldFit<FixedEnumFor_int64_t, int64_t>(); + + TestShouldNotFit<FixedEnumFor_int64_t, uint8_t>(); + TestShouldNotFit<FixedEnumFor_int64_t, uint16_t>(); + TestShouldNotFit<FixedEnumFor_int64_t, uint32_t>(); + TestShouldNotFit<FixedEnumFor_int64_t, uint64_t>(); + + // check for uint64_t + MAKE_FIXED_EMUM_FOR_TYPE(uint64_t); + TestShouldNotFit<FixedEnumFor_uint64_t, uint8_t>(); + TestShouldNotFit<FixedEnumFor_uint64_t, uint16_t>(); + TestShouldNotFit<FixedEnumFor_uint64_t, uint32_t>(); + TestShouldFit<FixedEnumFor_uint64_t, uint64_t>(); + + TestShouldNotFit<FixedEnumFor_uint64_t, int8_t>(); + TestShouldNotFit<FixedEnumFor_uint64_t, int16_t>(); + TestShouldNotFit<FixedEnumFor_uint64_t, int32_t>(); + TestShouldNotFit<FixedEnumFor_uint64_t, int64_t>(); + + return 0; +} diff --git a/mfbt/tests/TestEnumeratedArray.cpp b/mfbt/tests/TestEnumeratedArray.cpp new file mode 100644 index 000000000..bb73f21b7 --- /dev/null +++ b/mfbt/tests/TestEnumeratedArray.cpp @@ -0,0 +1,42 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/EnumeratedArray.h" + +enum class AnimalSpecies +{ + Cow, + Sheep, + Pig, + Count +}; + +void TestInitialValueByConstructor() +{ + using namespace mozilla; + // Style 1 + EnumeratedArray<AnimalSpecies, AnimalSpecies::Count, int> headCount(1, 2, 3); + MOZ_RELEASE_ASSERT(headCount[AnimalSpecies::Cow] == 1); + MOZ_RELEASE_ASSERT(headCount[AnimalSpecies::Sheep] == 2); + MOZ_RELEASE_ASSERT(headCount[AnimalSpecies::Pig] == 3); + // Style 2 + EnumeratedArray<AnimalSpecies, AnimalSpecies::Count, int> headCount2{5, 6, 7}; + MOZ_RELEASE_ASSERT(headCount2[AnimalSpecies::Cow] == 5); + MOZ_RELEASE_ASSERT(headCount2[AnimalSpecies::Sheep] == 6); + MOZ_RELEASE_ASSERT(headCount2[AnimalSpecies::Pig] == 7); + // Style 3 + EnumeratedArray<AnimalSpecies, AnimalSpecies::Count, int> headCount3({8, 9, 10}); + MOZ_RELEASE_ASSERT(headCount3[AnimalSpecies::Cow] == 8); + MOZ_RELEASE_ASSERT(headCount3[AnimalSpecies::Sheep] == 9); + MOZ_RELEASE_ASSERT(headCount3[AnimalSpecies::Pig] == 10); +} + +int +main() +{ + TestInitialValueByConstructor(); + return 0; +}
\ No newline at end of file diff --git a/mfbt/tests/TestFastBernoulliTrial.cpp b/mfbt/tests/TestFastBernoulliTrial.cpp new file mode 100644 index 000000000..62d4b51a7 --- /dev/null +++ b/mfbt/tests/TestFastBernoulliTrial.cpp @@ -0,0 +1,209 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/FastBernoulliTrial.h" + +#include <math.h> + +// Note that because we always provide FastBernoulliTrial with a fixed +// pseudorandom seed in these tests, the results here are completely +// deterministic. +// +// A non-optimized version of this test runs in .009s on my laptop. Using larger +// sample sizes lets us meet tighter bounds on the counts. + +static void +TestProportions() +{ + mozilla::FastBernoulliTrial bernoulli(1.0, + 698079309544035222ULL, + 6012389156611637584ULL); + + for (size_t i = 0; i < 100; i++) + MOZ_RELEASE_ASSERT(bernoulli.trial()); + + { + bernoulli.setProbability(0.5); + size_t count = 0; + for (size_t i = 0; i < 1000; i++) + count += bernoulli.trial(); + MOZ_RELEASE_ASSERT(count == 496); + } + + { + bernoulli.setProbability(0.001); + size_t count = 0; + for (size_t i = 0; i < 1000; i++) + count += bernoulli.trial(); + MOZ_RELEASE_ASSERT(count == 2); + } + + { + bernoulli.setProbability(0.85); + size_t count = 0; + for (size_t i = 0; i < 1000; i++) + count += bernoulli.trial(); + MOZ_RELEASE_ASSERT(count == 852); + } + + bernoulli.setProbability(0.0); + for (size_t i = 0; i < 100; i++) + MOZ_RELEASE_ASSERT(!bernoulli.trial()); +} + +static void +TestHarmonics() +{ + mozilla::FastBernoulliTrial bernoulli(0.1, + 698079309544035222ULL, + 6012389156611637584ULL); + + const size_t n = 100000; + bool trials[n]; + for (size_t i = 0; i < n; i++) + trials[i] = bernoulli.trial(); + + // For each harmonic and phase, check that the proportion sampled is + // within acceptable bounds. + for (size_t harmonic = 1; harmonic < 20; harmonic++) { + size_t expected = n / harmonic / 10; + size_t low_expected = expected * 85 / 100; + size_t high_expected = expected * 115 / 100; + + for (size_t phase = 0; phase < harmonic; phase++) { + size_t count = 0; + for (size_t i = phase; i < n; i += harmonic) + count += trials[i]; + + MOZ_RELEASE_ASSERT(low_expected <= count && count <= high_expected); + } + } +} + +static void +TestTrialN() +{ + mozilla::FastBernoulliTrial bernoulli(0.01, + 0x67ff17e25d855942ULL, + 0x74f298193fe1c5b1ULL); + + { + size_t count = 0; + for (size_t i = 0; i < 10000; i++) + count += bernoulli.trial(1); + + // Expected value: 0.01 * 10000 == 100 + MOZ_RELEASE_ASSERT(count == 97); + } + + { + size_t count = 0; + for (size_t i = 0; i < 10000; i++) + count += bernoulli.trial(3); + + // Expected value: (1 - (1 - 0.01) ** 3) == 0.0297, + // 0.0297 * 10000 == 297 + MOZ_RELEASE_ASSERT(count == 304); + } + + { + size_t count = 0; + for (size_t i = 0; i < 10000; i++) + count += bernoulli.trial(10); + + // Expected value: (1 - (1 - 0.01) ** 10) == 0.0956, + // 0.0956 * 10000 == 956 + MOZ_RELEASE_ASSERT(count == 936); + } + + { + size_t count = 0; + for (size_t i = 0; i < 10000; i++) + count += bernoulli.trial(100); + + // Expected value: (1 - (1 - 0.01) ** 100) == 0.6339 + // 0.6339 * 10000 == 6339 + MOZ_RELEASE_ASSERT(count == 6372); + } + + { + size_t count = 0; + for (size_t i = 0; i < 10000; i++) + count += bernoulli.trial(1000); + + // Expected value: (1 - (1 - 0.01) ** 1000) == 0.9999 + // 0.9999 * 10000 == 9999 + MOZ_RELEASE_ASSERT(count == 9998); + } +} + +static void +TestChangeProbability() +{ + mozilla::FastBernoulliTrial bernoulli(1.0, + 0x67ff17e25d855942ULL, + 0x74f298193fe1c5b1ULL); + + // Establish a very high skip count. + bernoulli.setProbability(0.0); + + // This should re-establish a zero skip count. + bernoulli.setProbability(1.0); + + // So this should return true. + MOZ_RELEASE_ASSERT(bernoulli.trial()); +} + +static void +TestCuspProbabilities() +{ + /* + * FastBernoulliTrial takes care to avoid screwing up on edge cases. The + * checks here all look pretty dumb, but they exercise paths in the code that + * could exhibit undefined behavior if coded naïvely. + */ + + /* + * This should not be perceptibly different from 1; for 64-bit doubles, this + * is a one in ten trillion chance of the trial not succeeding. Overflows + * converting doubles to size_t skip counts may change this, though. + */ + mozilla::FastBernoulliTrial bernoulli(nextafter(1, 0), + 0x67ff17e25d855942ULL, + 0x74f298193fe1c5b1ULL); + + for (size_t i = 0; i < 1000; i++) + MOZ_RELEASE_ASSERT(bernoulli.trial()); + + /* + * This should not be perceptibly different from 0; for 64-bit doubles, + * the FastBernoulliTrial will actually treat this as exactly zero. + */ + bernoulli.setProbability(nextafter(0, 1)); + for (size_t i = 0; i < 1000; i++) + MOZ_RELEASE_ASSERT(!bernoulli.trial()); + + /* + * This should be a vanishingly low probability which FastBernoulliTrial does + * *not* treat as exactly zero. + */ + bernoulli.setProbability(1 - nextafter(1, 0)); + for (size_t i = 0; i < 1000; i++) + MOZ_RELEASE_ASSERT(!bernoulli.trial()); +} + +int +main() +{ + TestProportions(); + TestHarmonics(); + TestTrialN(); + TestChangeProbability(); + TestCuspProbabilities(); + + return 0; +} diff --git a/mfbt/tests/TestFloatingPoint.cpp b/mfbt/tests/TestFloatingPoint.cpp new file mode 100644 index 000000000..f32e698de --- /dev/null +++ b/mfbt/tests/TestFloatingPoint.cpp @@ -0,0 +1,592 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/FloatingPoint.h" + +#include <math.h> + +using mozilla::ExponentComponent; +using mozilla::FloatingPoint; +using mozilla::FuzzyEqualsAdditive; +using mozilla::FuzzyEqualsMultiplicative; +using mozilla::IsFinite; +using mozilla::IsInfinite; +using mozilla::IsNaN; +using mozilla::IsNegative; +using mozilla::IsNegativeZero; +using mozilla::IsPositiveZero; +using mozilla::NegativeInfinity; +using mozilla::NumberEqualsInt32; +using mozilla::NumberIsInt32; +using mozilla::NumbersAreIdentical; +using mozilla::PositiveInfinity; +using mozilla::SpecificNaN; +using mozilla::UnspecifiedNaN; + +#define A(a) MOZ_RELEASE_ASSERT(a) + +template<typename T> +static void +ShouldBeIdentical(T aD1, T aD2) +{ + A(NumbersAreIdentical(aD1, aD2)); + A(NumbersAreIdentical(aD2, aD1)); +} + +template<typename T> +static void +ShouldNotBeIdentical(T aD1, T aD2) +{ + A(!NumbersAreIdentical(aD1, aD2)); + A(!NumbersAreIdentical(aD2, aD1)); +} + +static void +TestDoublesAreIdentical() +{ + ShouldBeIdentical(+0.0, +0.0); + ShouldBeIdentical(-0.0, -0.0); + ShouldNotBeIdentical(+0.0, -0.0); + + ShouldBeIdentical(1.0, 1.0); + ShouldNotBeIdentical(-1.0, 1.0); + ShouldBeIdentical(4294967295.0, 4294967295.0); + ShouldNotBeIdentical(-4294967295.0, 4294967295.0); + ShouldBeIdentical(4294967296.0, 4294967296.0); + ShouldBeIdentical(4294967297.0, 4294967297.0); + ShouldBeIdentical(1e300, 1e300); + + ShouldBeIdentical(PositiveInfinity<double>(), PositiveInfinity<double>()); + ShouldBeIdentical(NegativeInfinity<double>(), NegativeInfinity<double>()); + ShouldNotBeIdentical(PositiveInfinity<double>(), NegativeInfinity<double>()); + + ShouldNotBeIdentical(-0.0, NegativeInfinity<double>()); + ShouldNotBeIdentical(+0.0, NegativeInfinity<double>()); + ShouldNotBeIdentical(1e300, NegativeInfinity<double>()); + ShouldNotBeIdentical(3.141592654, NegativeInfinity<double>()); + + ShouldBeIdentical(UnspecifiedNaN<double>(), UnspecifiedNaN<double>()); + ShouldBeIdentical(-UnspecifiedNaN<double>(), UnspecifiedNaN<double>()); + ShouldBeIdentical(UnspecifiedNaN<double>(), -UnspecifiedNaN<double>()); + + ShouldBeIdentical(SpecificNaN<double>(0, 17), SpecificNaN<double>(0, 42)); + ShouldBeIdentical(SpecificNaN<double>(1, 17), SpecificNaN<double>(1, 42)); + ShouldBeIdentical(SpecificNaN<double>(0, 17), SpecificNaN<double>(1, 42)); + ShouldBeIdentical(SpecificNaN<double>(1, 17), SpecificNaN<double>(0, 42)); + + const uint64_t Mask = 0xfffffffffffffULL; + for (unsigned i = 0; i < 52; i++) { + for (unsigned j = 0; j < 52; j++) { + for (unsigned sign = 0; i < 2; i++) { + ShouldBeIdentical(SpecificNaN<double>(0, 1ULL << i), + SpecificNaN<double>(sign, 1ULL << j)); + ShouldBeIdentical(SpecificNaN<double>(1, 1ULL << i), + SpecificNaN<double>(sign, 1ULL << j)); + + ShouldBeIdentical(SpecificNaN<double>(0, Mask & ~(1ULL << i)), + SpecificNaN<double>(sign, Mask & ~(1ULL << j))); + ShouldBeIdentical(SpecificNaN<double>(1, Mask & ~(1ULL << i)), + SpecificNaN<double>(sign, Mask & ~(1ULL << j))); + } + } + } + ShouldBeIdentical(SpecificNaN<double>(0, 17), + SpecificNaN<double>(0, 0x8000000000000ULL)); + ShouldBeIdentical(SpecificNaN<double>(0, 17), + SpecificNaN<double>(0, 0x4000000000000ULL)); + ShouldBeIdentical(SpecificNaN<double>(0, 17), + SpecificNaN<double>(0, 0x2000000000000ULL)); + ShouldBeIdentical(SpecificNaN<double>(0, 17), + SpecificNaN<double>(0, 0x1000000000000ULL)); + ShouldBeIdentical(SpecificNaN<double>(0, 17), + SpecificNaN<double>(0, 0x0800000000000ULL)); + ShouldBeIdentical(SpecificNaN<double>(0, 17), + SpecificNaN<double>(0, 0x0400000000000ULL)); + ShouldBeIdentical(SpecificNaN<double>(0, 17), + SpecificNaN<double>(0, 0x0200000000000ULL)); + ShouldBeIdentical(SpecificNaN<double>(0, 17), + SpecificNaN<double>(0, 0x0100000000000ULL)); + ShouldBeIdentical(SpecificNaN<double>(0, 17), + SpecificNaN<double>(0, 0x0080000000000ULL)); + ShouldBeIdentical(SpecificNaN<double>(0, 17), + SpecificNaN<double>(0, 0x0040000000000ULL)); + ShouldBeIdentical(SpecificNaN<double>(0, 17), + SpecificNaN<double>(0, 0x0020000000000ULL)); + ShouldBeIdentical(SpecificNaN<double>(0, 17), + SpecificNaN<double>(0, 0x0010000000000ULL)); + ShouldBeIdentical(SpecificNaN<double>(1, 17), + SpecificNaN<double>(0, 0xff0ffffffffffULL)); + ShouldBeIdentical(SpecificNaN<double>(1, 17), + SpecificNaN<double>(0, 0xfffffffffff0fULL)); + + ShouldNotBeIdentical(UnspecifiedNaN<double>(), +0.0); + ShouldNotBeIdentical(UnspecifiedNaN<double>(), -0.0); + ShouldNotBeIdentical(UnspecifiedNaN<double>(), 1.0); + ShouldNotBeIdentical(UnspecifiedNaN<double>(), -1.0); + ShouldNotBeIdentical(UnspecifiedNaN<double>(), PositiveInfinity<double>()); + ShouldNotBeIdentical(UnspecifiedNaN<double>(), NegativeInfinity<double>()); +} + +static void +TestFloatsAreIdentical() +{ + ShouldBeIdentical(+0.0f, +0.0f); + ShouldBeIdentical(-0.0f, -0.0f); + ShouldNotBeIdentical(+0.0f, -0.0f); + + ShouldBeIdentical(1.0f, 1.0f); + ShouldNotBeIdentical(-1.0f, 1.0f); + ShouldBeIdentical(8388607.0f, 8388607.0f); + ShouldNotBeIdentical(-8388607.0f, 8388607.0f); + ShouldBeIdentical(8388608.0f, 8388608.0f); + ShouldBeIdentical(8388609.0f, 8388609.0f); + ShouldBeIdentical(1e36f, 1e36f); + + ShouldBeIdentical(PositiveInfinity<float>(), PositiveInfinity<float>()); + ShouldBeIdentical(NegativeInfinity<float>(), NegativeInfinity<float>()); + ShouldNotBeIdentical(PositiveInfinity<float>(), NegativeInfinity<float>()); + + ShouldNotBeIdentical(-0.0f, NegativeInfinity<float>()); + ShouldNotBeIdentical(+0.0f, NegativeInfinity<float>()); + ShouldNotBeIdentical(1e36f, NegativeInfinity<float>()); + ShouldNotBeIdentical(3.141592654f, NegativeInfinity<float>()); + + ShouldBeIdentical(UnspecifiedNaN<float>(), UnspecifiedNaN<float>()); + ShouldBeIdentical(-UnspecifiedNaN<float>(), UnspecifiedNaN<float>()); + ShouldBeIdentical(UnspecifiedNaN<float>(), -UnspecifiedNaN<float>()); + + ShouldBeIdentical(SpecificNaN<float>(0, 17), SpecificNaN<float>(0, 42)); + ShouldBeIdentical(SpecificNaN<float>(1, 17), SpecificNaN<float>(1, 42)); + ShouldBeIdentical(SpecificNaN<float>(0, 17), SpecificNaN<float>(1, 42)); + ShouldBeIdentical(SpecificNaN<float>(1, 17), SpecificNaN<float>(0, 42)); + + const uint32_t Mask = 0x7fffffUL; + for (unsigned i = 0; i < 23; i++) { + for (unsigned j = 0; j < 23; j++) { + for (unsigned sign = 0; i < 2; i++) { + ShouldBeIdentical(SpecificNaN<float>(0, 1UL << i), + SpecificNaN<float>(sign, 1UL << j)); + ShouldBeIdentical(SpecificNaN<float>(1, 1UL << i), + SpecificNaN<float>(sign, 1UL << j)); + + ShouldBeIdentical(SpecificNaN<float>(0, Mask & ~(1UL << i)), + SpecificNaN<float>(sign, Mask & ~(1UL << j))); + ShouldBeIdentical(SpecificNaN<float>(1, Mask & ~(1UL << i)), + SpecificNaN<float>(sign, Mask & ~(1UL << j))); + } + } + } + ShouldBeIdentical(SpecificNaN<float>(0, 17), SpecificNaN<float>(0, 0x700000)); + ShouldBeIdentical(SpecificNaN<float>(0, 17), SpecificNaN<float>(0, 0x400000)); + ShouldBeIdentical(SpecificNaN<float>(0, 17), SpecificNaN<float>(0, 0x200000)); + ShouldBeIdentical(SpecificNaN<float>(0, 17), SpecificNaN<float>(0, 0x100000)); + ShouldBeIdentical(SpecificNaN<float>(0, 17), SpecificNaN<float>(0, 0x080000)); + ShouldBeIdentical(SpecificNaN<float>(0, 17), SpecificNaN<float>(0, 0x040000)); + ShouldBeIdentical(SpecificNaN<float>(0, 17), SpecificNaN<float>(0, 0x020000)); + ShouldBeIdentical(SpecificNaN<float>(0, 17), SpecificNaN<float>(0, 0x010000)); + ShouldBeIdentical(SpecificNaN<float>(0, 17), SpecificNaN<float>(0, 0x008000)); + ShouldBeIdentical(SpecificNaN<float>(0, 17), SpecificNaN<float>(0, 0x004000)); + ShouldBeIdentical(SpecificNaN<float>(0, 17), SpecificNaN<float>(0, 0x002000)); + ShouldBeIdentical(SpecificNaN<float>(0, 17), SpecificNaN<float>(0, 0x001000)); + ShouldBeIdentical(SpecificNaN<float>(1, 17), SpecificNaN<float>(0, 0x7f0fff)); + ShouldBeIdentical(SpecificNaN<float>(1, 17), SpecificNaN<float>(0, 0x7fff0f)); + + ShouldNotBeIdentical(UnspecifiedNaN<float>(), +0.0f); + ShouldNotBeIdentical(UnspecifiedNaN<float>(), -0.0f); + ShouldNotBeIdentical(UnspecifiedNaN<float>(), 1.0f); + ShouldNotBeIdentical(UnspecifiedNaN<float>(), -1.0f); + ShouldNotBeIdentical(UnspecifiedNaN<float>(), PositiveInfinity<float>()); + ShouldNotBeIdentical(UnspecifiedNaN<float>(), NegativeInfinity<float>()); +} + +static void +TestAreIdentical() +{ + TestDoublesAreIdentical(); + TestFloatsAreIdentical(); +} + +static void +TestDoubleExponentComponent() +{ + A(ExponentComponent(0.0) == + -int_fast16_t(FloatingPoint<double>::kExponentBias)); + A(ExponentComponent(-0.0) == + -int_fast16_t(FloatingPoint<double>::kExponentBias)); + A(ExponentComponent(0.125) == -3); + A(ExponentComponent(0.5) == -1); + A(ExponentComponent(1.0) == 0); + A(ExponentComponent(1.5) == 0); + A(ExponentComponent(2.0) == 1); + A(ExponentComponent(7.0) == 2); + A(ExponentComponent(PositiveInfinity<double>()) == + FloatingPoint<double>::kExponentBias + 1); + A(ExponentComponent(NegativeInfinity<double>()) == + FloatingPoint<double>::kExponentBias + 1); + A(ExponentComponent(UnspecifiedNaN<double>()) == + FloatingPoint<double>::kExponentBias + 1); +} + +static void +TestFloatExponentComponent() +{ + A(ExponentComponent(0.0f) == + -int_fast16_t(FloatingPoint<float>::kExponentBias)); + A(ExponentComponent(-0.0f) == + -int_fast16_t(FloatingPoint<float>::kExponentBias)); + A(ExponentComponent(0.125f) == -3); + A(ExponentComponent(0.5f) == -1); + A(ExponentComponent(1.0f) == 0); + A(ExponentComponent(1.5f) == 0); + A(ExponentComponent(2.0f) == 1); + A(ExponentComponent(7.0f) == 2); + A(ExponentComponent(PositiveInfinity<float>()) == + FloatingPoint<float>::kExponentBias + 1); + A(ExponentComponent(NegativeInfinity<float>()) == + FloatingPoint<float>::kExponentBias + 1); + A(ExponentComponent(UnspecifiedNaN<float>()) == + FloatingPoint<float>::kExponentBias + 1); +} + +static void +TestExponentComponent() +{ + TestDoubleExponentComponent(); + TestFloatExponentComponent(); +} + +static void +TestDoublesPredicates() +{ + A(IsNaN(UnspecifiedNaN<double>())); + A(IsNaN(SpecificNaN<double>(1, 17)));; + A(IsNaN(SpecificNaN<double>(0, 0xfffffffffff0fULL))); + A(!IsNaN(0.0)); + A(!IsNaN(-0.0)); + A(!IsNaN(1.0)); + A(!IsNaN(PositiveInfinity<double>())); + A(!IsNaN(NegativeInfinity<double>())); + + A(IsInfinite(PositiveInfinity<double>())); + A(IsInfinite(NegativeInfinity<double>())); + A(!IsInfinite(UnspecifiedNaN<double>())); + A(!IsInfinite(0.0)); + A(!IsInfinite(-0.0)); + A(!IsInfinite(1.0)); + + A(!IsFinite(PositiveInfinity<double>())); + A(!IsFinite(NegativeInfinity<double>())); + A(!IsFinite(UnspecifiedNaN<double>())); + A(IsFinite(0.0)); + A(IsFinite(-0.0)); + A(IsFinite(1.0)); + + A(!IsNegative(PositiveInfinity<double>())); + A(IsNegative(NegativeInfinity<double>())); + A(IsNegative(-0.0)); + A(!IsNegative(0.0)); + A(IsNegative(-1.0)); + A(!IsNegative(1.0)); + + A(!IsNegativeZero(PositiveInfinity<double>())); + A(!IsNegativeZero(NegativeInfinity<double>())); + A(!IsNegativeZero(SpecificNaN<double>(1, 17)));; + A(!IsNegativeZero(SpecificNaN<double>(1, 0xfffffffffff0fULL))); + A(!IsNegativeZero(SpecificNaN<double>(0, 17)));; + A(!IsNegativeZero(SpecificNaN<double>(0, 0xfffffffffff0fULL))); + A(!IsNegativeZero(UnspecifiedNaN<double>())); + A(IsNegativeZero(-0.0)); + A(!IsNegativeZero(0.0)); + A(!IsNegativeZero(-1.0)); + A(!IsNegativeZero(1.0)); + + int32_t i; + A(NumberIsInt32(0.0, &i)); + A(i == 0); + A(!NumberIsInt32(-0.0, &i)); + A(NumberEqualsInt32(0.0, &i)); + A(i == 0); + A(NumberEqualsInt32(-0.0, &i)); + A(i == 0); + A(NumberIsInt32(double(INT32_MIN), &i)); + A(i == INT32_MIN); + A(NumberIsInt32(double(INT32_MAX), &i)); + A(i == INT32_MAX); + A(NumberEqualsInt32(double(INT32_MIN), &i)); + A(i == INT32_MIN); + A(NumberEqualsInt32(double(INT32_MAX), &i)); + A(i == INT32_MAX); + A(!NumberIsInt32(0.5, &i)); + A(!NumberIsInt32(double(INT32_MAX) + 0.1, &i)); + A(!NumberIsInt32(double(INT32_MIN) - 0.1, &i)); + A(!NumberIsInt32(NegativeInfinity<double>(), &i)); + A(!NumberIsInt32(PositiveInfinity<double>(), &i)); + A(!NumberIsInt32(UnspecifiedNaN<double>(), &i)); + A(!NumberEqualsInt32(0.5, &i)); + A(!NumberEqualsInt32(double(INT32_MAX) + 0.1, &i)); + A(!NumberEqualsInt32(double(INT32_MIN) - 0.1, &i)); + A(!NumberEqualsInt32(NegativeInfinity<double>(), &i)); + A(!NumberEqualsInt32(PositiveInfinity<double>(), &i)); + A(!NumberEqualsInt32(UnspecifiedNaN<double>(), &i)); +} + +static void +TestFloatsPredicates() +{ + A(IsNaN(UnspecifiedNaN<float>())); + A(IsNaN(SpecificNaN<float>(1, 17)));; + A(IsNaN(SpecificNaN<float>(0, 0x7fff0fUL))); + A(!IsNaN(0.0f)); + A(!IsNaN(-0.0f)); + A(!IsNaN(1.0f)); + A(!IsNaN(PositiveInfinity<float>())); + A(!IsNaN(NegativeInfinity<float>())); + + A(IsInfinite(PositiveInfinity<float>())); + A(IsInfinite(NegativeInfinity<float>())); + A(!IsInfinite(UnspecifiedNaN<float>())); + A(!IsInfinite(0.0f)); + A(!IsInfinite(-0.0f)); + A(!IsInfinite(1.0f)); + + A(!IsFinite(PositiveInfinity<float>())); + A(!IsFinite(NegativeInfinity<float>())); + A(!IsFinite(UnspecifiedNaN<float>())); + A(IsFinite(0.0f)); + A(IsFinite(-0.0f)); + A(IsFinite(1.0f)); + + A(!IsNegative(PositiveInfinity<float>())); + A(IsNegative(NegativeInfinity<float>())); + A(IsNegative(-0.0f)); + A(!IsNegative(0.0f)); + A(IsNegative(-1.0f)); + A(!IsNegative(1.0f)); + + A(!IsNegativeZero(PositiveInfinity<float>())); + A(!IsNegativeZero(NegativeInfinity<float>())); + A(!IsNegativeZero(SpecificNaN<float>(1, 17)));; + A(!IsNegativeZero(SpecificNaN<float>(1, 0x7fff0fUL))); + A(!IsNegativeZero(SpecificNaN<float>(0, 17)));; + A(!IsNegativeZero(SpecificNaN<float>(0, 0x7fff0fUL))); + A(!IsNegativeZero(UnspecifiedNaN<float>())); + A(IsNegativeZero(-0.0f)); + A(!IsNegativeZero(0.0f)); + A(!IsNegativeZero(-1.0f)); + A(!IsNegativeZero(1.0f)); + + A(!IsPositiveZero(PositiveInfinity<float>())); + A(!IsPositiveZero(NegativeInfinity<float>())); + A(!IsPositiveZero(SpecificNaN<float>(1, 17)));; + A(!IsPositiveZero(SpecificNaN<float>(1, 0x7fff0fUL))); + A(!IsPositiveZero(SpecificNaN<float>(0, 17)));; + A(!IsPositiveZero(SpecificNaN<float>(0, 0x7fff0fUL))); + A(!IsPositiveZero(UnspecifiedNaN<float>())); + A(IsPositiveZero(0.0f)); + A(!IsPositiveZero(-0.0f)); + A(!IsPositiveZero(-1.0f)); + A(!IsPositiveZero(1.0f)); + + int32_t i; + const int32_t BIG = 2097151; + A(NumberIsInt32(0.0f, &i)); + A(i == 0); + A(!NumberIsInt32(-0.0f, &i)); + A(NumberEqualsInt32(0.0f, &i)); + A(i == 0); + A(NumberEqualsInt32(-0.0f, &i)); + A(i == 0); + A(NumberIsInt32(float(INT32_MIN), &i)); + A(i == INT32_MIN); + A(NumberIsInt32(float(BIG), &i)); + A(i == BIG); + A(NumberEqualsInt32(float(INT32_MIN), &i)); + A(i == INT32_MIN); + A(NumberEqualsInt32(float(BIG), &i)); + A(i == BIG); + A(!NumberIsInt32(0.5f, &i)); + A(!NumberIsInt32(float(BIG) + 0.1f, &i)); + A(!NumberIsInt32(NegativeInfinity<float>(), &i)); + A(!NumberIsInt32(PositiveInfinity<float>(), &i)); + A(!NumberIsInt32(UnspecifiedNaN<float>(), &i)); + A(!NumberEqualsInt32(0.5f, &i)); + A(!NumberEqualsInt32(float(BIG) + 0.1f, &i)); + A(!NumberEqualsInt32(NegativeInfinity<float>(), &i)); + A(!NumberEqualsInt32(PositiveInfinity<float>(), &i)); + A(!NumberEqualsInt32(UnspecifiedNaN<float>(), &i)); +} + +static void +TestPredicates() +{ + TestFloatsPredicates(); + TestDoublesPredicates(); +} + +static void +TestFloatsAreApproximatelyEqual() +{ + float epsilon = mozilla::detail::FuzzyEqualsEpsilon<float>::value(); + float lessThanEpsilon = epsilon / 2.0f; + float moreThanEpsilon = epsilon * 2.0f; + + // Additive tests using the default epsilon + // ... around 1.0 + A(FuzzyEqualsAdditive(1.0f, 1.0f + lessThanEpsilon)); + A(FuzzyEqualsAdditive(1.0f, 1.0f - lessThanEpsilon)); + A(FuzzyEqualsAdditive(1.0f, 1.0f + epsilon)); + A(FuzzyEqualsAdditive(1.0f, 1.0f - epsilon)); + A(!FuzzyEqualsAdditive(1.0f, 1.0f + moreThanEpsilon)); + A(!FuzzyEqualsAdditive(1.0f, 1.0f - moreThanEpsilon)); + // ... around 1.0e2 (this is near the upper bound of the range where + // adding moreThanEpsilon will still be representable and return false) + A(FuzzyEqualsAdditive(1.0e2f, 1.0e2f + lessThanEpsilon)); + A(FuzzyEqualsAdditive(1.0e2f, 1.0e2f + epsilon)); + A(!FuzzyEqualsAdditive(1.0e2f, 1.0e2f + moreThanEpsilon)); + // ... around 1.0e-10 + A(FuzzyEqualsAdditive(1.0e-10f, 1.0e-10f + lessThanEpsilon)); + A(FuzzyEqualsAdditive(1.0e-10f, 1.0e-10f + epsilon)); + A(!FuzzyEqualsAdditive(1.0e-10f, 1.0e-10f + moreThanEpsilon)); + // ... straddling 0 + A(FuzzyEqualsAdditive(1.0e-6f, -1.0e-6f)); + A(!FuzzyEqualsAdditive(1.0e-5f, -1.0e-5f)); + // Using a small epsilon + A(FuzzyEqualsAdditive(1.0e-5f, 1.0e-5f + 1.0e-10f, 1.0e-9f)); + A(!FuzzyEqualsAdditive(1.0e-5f, 1.0e-5f + 1.0e-10f, 1.0e-11f)); + // Using a big epsilon + A(FuzzyEqualsAdditive(1.0e20f, 1.0e20f + 1.0e15f, 1.0e16f)); + A(!FuzzyEqualsAdditive(1.0e20f, 1.0e20f + 1.0e15f, 1.0e14f)); + + // Multiplicative tests using the default epsilon + // ... around 1.0 + A(FuzzyEqualsMultiplicative(1.0f, 1.0f + lessThanEpsilon)); + A(FuzzyEqualsMultiplicative(1.0f, 1.0f - lessThanEpsilon)); + A(FuzzyEqualsMultiplicative(1.0f, 1.0f + epsilon)); + A(!FuzzyEqualsMultiplicative(1.0f, 1.0f - epsilon)); + A(!FuzzyEqualsMultiplicative(1.0f, 1.0f + moreThanEpsilon)); + A(!FuzzyEqualsMultiplicative(1.0f, 1.0f - moreThanEpsilon)); + // ... around 1.0e10 + A(FuzzyEqualsMultiplicative(1.0e10f, 1.0e10f + (lessThanEpsilon * 1.0e10f))); + A(!FuzzyEqualsMultiplicative(1.0e10f, 1.0e10f + (moreThanEpsilon * 1.0e10f))); + // ... around 1.0e-10 + A(FuzzyEqualsMultiplicative(1.0e-10f, + 1.0e-10f + (lessThanEpsilon * 1.0e-10f))); + A(!FuzzyEqualsMultiplicative(1.0e-10f, + 1.0e-10f + (moreThanEpsilon * 1.0e-10f))); + // ... straddling 0 + A(!FuzzyEqualsMultiplicative(1.0e-6f, -1.0e-6f)); + A(FuzzyEqualsMultiplicative(1.0e-6f, -1.0e-6f, 1.0e2f)); + // Using a small epsilon + A(FuzzyEqualsMultiplicative(1.0e-5f, 1.0e-5f + 1.0e-10f, 1.0e-4f)); + A(!FuzzyEqualsMultiplicative(1.0e-5f, 1.0e-5f + 1.0e-10f, 1.0e-5f)); + // Using a big epsilon + A(FuzzyEqualsMultiplicative(1.0f, 2.0f, 1.0f)); + A(!FuzzyEqualsMultiplicative(1.0f, 2.0f, 0.1f)); + + // "real world case" + float oneThird = 10.0f / 3.0f; + A(FuzzyEqualsAdditive(10.0f, 3.0f * oneThird)); + A(FuzzyEqualsMultiplicative(10.0f, 3.0f * oneThird)); + // NaN check + A(!FuzzyEqualsAdditive(SpecificNaN<float>(1, 1), SpecificNaN<float>(1, 1))); + A(!FuzzyEqualsAdditive(SpecificNaN<float>(1, 2), SpecificNaN<float>(0, 8))); + A(!FuzzyEqualsMultiplicative(SpecificNaN<float>(1, 1), + SpecificNaN<float>(1, 1))); + A(!FuzzyEqualsMultiplicative(SpecificNaN<float>(1, 2), + SpecificNaN<float>(0, 200))); +} + +static void +TestDoublesAreApproximatelyEqual() +{ + double epsilon = mozilla::detail::FuzzyEqualsEpsilon<double>::value(); + double lessThanEpsilon = epsilon / 2.0; + double moreThanEpsilon = epsilon * 2.0; + + // Additive tests using the default epsilon + // ... around 1.0 + A(FuzzyEqualsAdditive(1.0, 1.0 + lessThanEpsilon)); + A(FuzzyEqualsAdditive(1.0, 1.0 - lessThanEpsilon)); + A(FuzzyEqualsAdditive(1.0, 1.0 + epsilon)); + A(FuzzyEqualsAdditive(1.0, 1.0 - epsilon)); + A(!FuzzyEqualsAdditive(1.0, 1.0 + moreThanEpsilon)); + A(!FuzzyEqualsAdditive(1.0, 1.0 - moreThanEpsilon)); + // ... around 1.0e4 (this is near the upper bound of the range where + // adding moreThanEpsilon will still be representable and return false) + A(FuzzyEqualsAdditive(1.0e4, 1.0e4 + lessThanEpsilon)); + A(FuzzyEqualsAdditive(1.0e4, 1.0e4 + epsilon)); + A(!FuzzyEqualsAdditive(1.0e4, 1.0e4 + moreThanEpsilon)); + // ... around 1.0e-25 + A(FuzzyEqualsAdditive(1.0e-25, 1.0e-25 + lessThanEpsilon)); + A(FuzzyEqualsAdditive(1.0e-25, 1.0e-25 + epsilon)); + A(!FuzzyEqualsAdditive(1.0e-25, 1.0e-25 + moreThanEpsilon)); + // ... straddling 0 + A(FuzzyEqualsAdditive(1.0e-13, -1.0e-13)); + A(!FuzzyEqualsAdditive(1.0e-12, -1.0e-12)); + // Using a small epsilon + A(FuzzyEqualsAdditive(1.0e-15, 1.0e-15 + 1.0e-30, 1.0e-29)); + A(!FuzzyEqualsAdditive(1.0e-15, 1.0e-15 + 1.0e-30, 1.0e-31)); + // Using a big epsilon + A(FuzzyEqualsAdditive(1.0e40, 1.0e40 + 1.0e25, 1.0e26)); + A(!FuzzyEqualsAdditive(1.0e40, 1.0e40 + 1.0e25, 1.0e24)); + + // Multiplicative tests using the default epsilon + // ... around 1.0 + A(FuzzyEqualsMultiplicative(1.0, 1.0 + lessThanEpsilon)); + A(FuzzyEqualsMultiplicative(1.0, 1.0 - lessThanEpsilon)); + A(FuzzyEqualsMultiplicative(1.0, 1.0 + epsilon)); + A(!FuzzyEqualsMultiplicative(1.0, 1.0 - epsilon)); + A(!FuzzyEqualsMultiplicative(1.0, 1.0 + moreThanEpsilon)); + A(!FuzzyEqualsMultiplicative(1.0, 1.0 - moreThanEpsilon)); + // ... around 1.0e30 + A(FuzzyEqualsMultiplicative(1.0e30, 1.0e30 + (lessThanEpsilon * 1.0e30))); + A(!FuzzyEqualsMultiplicative(1.0e30, 1.0e30 + (moreThanEpsilon * 1.0e30))); + // ... around 1.0e-30 + A(FuzzyEqualsMultiplicative(1.0e-30, 1.0e-30 + (lessThanEpsilon * 1.0e-30))); + A(!FuzzyEqualsMultiplicative(1.0e-30, 1.0e-30 + (moreThanEpsilon * 1.0e-30))); + // ... straddling 0 + A(!FuzzyEqualsMultiplicative(1.0e-6, -1.0e-6)); + A(FuzzyEqualsMultiplicative(1.0e-6, -1.0e-6, 1.0e2)); + // Using a small epsilon + A(FuzzyEqualsMultiplicative(1.0e-15, 1.0e-15 + 1.0e-30, 1.0e-15)); + A(!FuzzyEqualsMultiplicative(1.0e-15, 1.0e-15 + 1.0e-30, 1.0e-16)); + // Using a big epsilon + A(FuzzyEqualsMultiplicative(1.0e40, 2.0e40, 1.0)); + A(!FuzzyEqualsMultiplicative(1.0e40, 2.0e40, 0.1)); + + // "real world case" + double oneThird = 10.0 / 3.0; + A(FuzzyEqualsAdditive(10.0, 3.0 * oneThird)); + A(FuzzyEqualsMultiplicative(10.0, 3.0 * oneThird)); + // NaN check + A(!FuzzyEqualsAdditive(SpecificNaN<double>(1, 1), + SpecificNaN<double>(1, 1))); + A(!FuzzyEqualsAdditive(SpecificNaN<double>(1, 2), + SpecificNaN<double>(0, 8))); + A(!FuzzyEqualsMultiplicative(SpecificNaN<double>(1, 1), + SpecificNaN<double>(1, 1))); + A(!FuzzyEqualsMultiplicative(SpecificNaN<double>(1, 2), + SpecificNaN<double>(0, 200))); +} + +static void +TestAreApproximatelyEqual() +{ + TestFloatsAreApproximatelyEqual(); + TestDoublesAreApproximatelyEqual(); +} + +#undef A + +int +main() +{ + TestAreIdentical(); + TestExponentComponent(); + TestPredicates(); + TestAreApproximatelyEqual(); + return 0; +} diff --git a/mfbt/tests/TestFunction.cpp b/mfbt/tests/TestFunction.cpp new file mode 100644 index 000000000..f9f36ce27 --- /dev/null +++ b/mfbt/tests/TestFunction.cpp @@ -0,0 +1,115 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ + /* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/Function.h" + +using mozilla::function; + +#define CHECK(c) \ + do { \ + bool cond = !!(c); \ + MOZ_RELEASE_ASSERT(cond, "Failed assertion: " #c); \ + } while (false) + +struct ConvertibleToInt +{ + operator int() const { return 42; } +}; + +int increment(int arg) { return arg + 1; } + +struct S { + S() {} + static int increment(int arg) { return arg + 1; } + int decrement(int arg) { return arg - 1;} + int sum(int arg1, int arg2) const { return arg1 + arg2;} +}; + +struct Incrementor { + int operator()(int arg) { return arg + 1; } +}; + +static void +TestNonmemberFunction() +{ + function<int(int)> f = &increment; + CHECK(f(42) == 43); +} + +static void +TestStaticMemberFunction() +{ + function<int(int)> f = &S::increment; + CHECK(f(42) == 43); +} + +static void +TestFunctionObject() +{ + function<int(int)> f = Incrementor(); + CHECK(f(42) == 43); +} + +static void +TestLambda() +{ + // Test non-capturing lambda + function<int(int)> f = [](int arg){ return arg + 1; }; + CHECK(f(42) == 43); + + // Test capturing lambda + int one = 1; + function<int(int)> g = [one](int arg){ return arg + one; }; + CHECK(g(42) == 43); +} + +static void +TestDefaultConstructionAndAssignmentLater() +{ + function<int(int)> f; // allowed + // Would get an assertion if we tried calling f now. + f = &increment; + CHECK(f(42) == 43); +} + +static void +TestReassignment() +{ + function<int(int)> f = &increment; + CHECK(f(42) == 43); + f = [](int arg){ return arg + 2; }; + CHECK(f(42) == 44); +} + +static void +TestMemberFunction() +{ + function<int(S&, int)> f = &S::decrement; + S s; + CHECK((f(s, 1) == 0)); +} + +static void +TestConstMemberFunction() +{ + function<int(const S*, int, int)> f = &S::sum; + const S s; + CHECK((f(&s, 1, 1) == 2)); +} +int +main() +{ + TestNonmemberFunction(); + TestStaticMemberFunction(); + TestFunctionObject(); + TestLambda(); + TestDefaultConstructionAndAssignmentLater(); + TestReassignment(); + TestMemberFunction(); + TestConstMemberFunction(); + return 0; +} diff --git a/mfbt/tests/TestIntegerPrintfMacros.cpp b/mfbt/tests/TestIntegerPrintfMacros.cpp new file mode 100644 index 000000000..475a88b63 --- /dev/null +++ b/mfbt/tests/TestIntegerPrintfMacros.cpp @@ -0,0 +1,1269 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/IntegerPrintfMacros.h" // this must pick up <stdint.h> +#include "mozilla/Sprintf.h" + +#include <stddef.h> +#include <stdio.h> +#include <string.h> + +/* Output array and poisoning method shared by all tests. */ +static char gOutput[32]; + +static void +PoisonOutput() +{ + memset(gOutput, 0xDA, sizeof(gOutput)); +} + +/* + * The fprintf macros for signed integers are: + * + * PRIdN PRIdLEASTN PRIdFASTN PRIdMAX PRIdPTR + * PRIiN PRIiLEASTN PRIiFASTN PRIiMAX PRIiPTR + * + * In these names N is the width of the type as described in C99 7.18.1. + */ + +static void +TestPrintSigned8() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRId8, int8_t(-17)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "-17")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIi8, int8_t(42)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "42")); +} + +static void +TestPrintSigned16() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRId16, int16_t(-289)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "-289")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIi16, int16_t(728)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "728")); +} + +static void +TestPrintSigned32() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRId32, int32_t(-342178)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "-342178")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIi32, int32_t(5719283)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "5719283")); +} + +static void +TestPrintSigned64() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRId64, int64_t(-INT64_C(432157943248732))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "-432157943248732")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIi64, int64_t(INT64_C(325719232983))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "325719232983")); +} + +static void +TestPrintSignedN() +{ + TestPrintSigned8(); + TestPrintSigned16(); + TestPrintSigned32(); + TestPrintSigned64(); +} + +static void +TestPrintSignedLeast8() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIdLEAST8, int_least8_t(-17)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "-17")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIiLEAST8, int_least8_t(42)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "42")); +} + +static void +TestPrintSignedLeast16() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIdLEAST16, int_least16_t(-289)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "-289")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIiLEAST16, int_least16_t(728)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "728")); +} + +static void +TestPrintSignedLeast32() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIdLEAST32, int_least32_t(-342178)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "-342178")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIiLEAST32, int_least32_t(5719283)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "5719283")); +} + +static void +TestPrintSignedLeast64() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIdLEAST64, int_least64_t(-INT64_C(432157943248732))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "-432157943248732")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIiLEAST64, int_least64_t(INT64_C(325719232983))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "325719232983")); +} + +static void +TestPrintSignedLeastN() +{ + TestPrintSignedLeast8(); + TestPrintSignedLeast16(); + TestPrintSignedLeast32(); + TestPrintSignedLeast64(); +} + +static void +TestPrintSignedFast8() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIdFAST8, int_fast8_t(-17)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "-17")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIiFAST8, int_fast8_t(42)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "42")); +} + +static void +TestPrintSignedFast16() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIdFAST16, int_fast16_t(-289)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "-289")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIiFAST16, int_fast16_t(728)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "728")); +} + +static void +TestPrintSignedFast32() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIdFAST32, int_fast32_t(-342178)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "-342178")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIiFAST32, int_fast32_t(5719283)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "5719283")); +} + +static void +TestPrintSignedFast64() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIdFAST64, int_fast64_t(-INT64_C(432157943248732))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "-432157943248732")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIiFAST64, int_fast64_t(INT64_C(325719232983))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "325719232983")); +} + +static void +TestPrintSignedFastN() +{ + TestPrintSignedFast8(); + TestPrintSignedFast16(); + TestPrintSignedFast32(); + TestPrintSignedFast64(); +} + +static void +TestPrintSignedMax() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIdMAX, intmax_t(-INTMAX_C(432157943248732))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "-432157943248732")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIiMAX, intmax_t(INTMAX_C(325719232983))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "325719232983")); +} + +static void +TestPrintSignedPtr() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIdPTR, intptr_t(reinterpret_cast<void*>(12345678))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "12345678")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIiPTR, intptr_t(reinterpret_cast<void*>(87654321))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "87654321")); +} + +static void +TestPrintSigned() +{ + TestPrintSignedN(); + TestPrintSignedLeastN(); + TestPrintSignedFastN(); + TestPrintSignedMax(); + TestPrintSignedPtr(); +} + +/* + * The fprintf macros for unsigned integers are: + * + * PRIoN PRIoLEASTN PRIoFASTN PRIoMAX PRIoPTR + * PRIuN PRIuLEASTN PRIuFASTN PRIuMAX PRIuPTR + * PRIxN PRIxLEASTN PRIxFASTN PRIxMAX PRIxPTR + * PRIXN PRIXLEASTN PRIXFASTN PRIXMAX PRIXPTR + * + * In these names N is the width of the type as described in C99 7.18.1. + */ + +static void +TestPrintUnsigned8() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIo8, uint8_t(042)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "42")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIu8, uint8_t(17)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "17")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIx8, uint8_t(0x2a)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "2a")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIX8, uint8_t(0xCD)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "CD")); +} + +static void +TestPrintUnsigned16() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIo16, uint16_t(04242)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "4242")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIu16, uint16_t(1717)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "1717")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIx16, uint16_t(0x2a2a)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "2a2a")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIX16, uint16_t(0xCDCD)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "CDCD")); +} + +static void +TestPrintUnsigned32() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIo32, uint32_t(0424242)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "424242")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIu32, uint32_t(171717)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "171717")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIx32, uint32_t(0x2a2a2a)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "2a2a2a")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIX32, uint32_t(0xCDCDCD)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "CDCDCD")); +} + +static void +TestPrintUnsigned64() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIo64, uint64_t(UINT64_C(0424242424242))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "424242424242")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIu64, uint64_t(UINT64_C(17171717171717171717))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "17171717171717171717")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIx64, uint64_t(UINT64_C(0x2a2a2a2a2a2a2a))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "2a2a2a2a2a2a2a")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIX64, uint64_t(UINT64_C(0xCDCDCDCDCDCD))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "CDCDCDCDCDCD")); +} + +static void +TestPrintUnsignedN() +{ + TestPrintUnsigned8(); + TestPrintUnsigned16(); + TestPrintUnsigned32(); + TestPrintUnsigned64(); +} + +static void +TestPrintUnsignedLeast8() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIoLEAST8, uint_least8_t(042)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "42")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIuLEAST8, uint_least8_t(17)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "17")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIxLEAST8, uint_least8_t(0x2a)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "2a")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIXLEAST8, uint_least8_t(0xCD)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "CD")); +} + +static void +TestPrintUnsignedLeast16() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIoLEAST16, uint_least16_t(04242)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "4242")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIuLEAST16, uint_least16_t(1717)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "1717")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIxLEAST16, uint_least16_t(0x2a2a)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "2a2a")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIXLEAST16, uint_least16_t(0xCDCD)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "CDCD")); +} + +static void +TestPrintUnsignedLeast32() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIoLEAST32, uint_least32_t(0424242)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "424242")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIuLEAST32, uint_least32_t(171717)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "171717")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIxLEAST32, uint_least32_t(0x2a2a2a)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "2a2a2a")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIXLEAST32, uint_least32_t(0xCDCDCD)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "CDCDCD")); +} + +static void +TestPrintUnsignedLeast64() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIoLEAST64, uint_least64_t(UINT64_C(0424242424242))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "424242424242")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIuLEAST64, + uint_least64_t(UINT64_C(17171717171717171717))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "17171717171717171717")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIxLEAST64, uint_least64_t(UINT64_C(0x2a2a2a2a2a2a2a))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "2a2a2a2a2a2a2a")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIXLEAST64, uint_least64_t(UINT64_C(0xCDCDCDCDCDCD))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "CDCDCDCDCDCD")); +} + +static void +TestPrintUnsignedLeastN() +{ + TestPrintUnsignedLeast8(); + TestPrintUnsignedLeast16(); + TestPrintUnsignedLeast32(); + TestPrintUnsignedLeast64(); +} + +static void +TestPrintUnsignedFast8() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIoFAST8, uint_fast8_t(042)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "42")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIuFAST8, uint_fast8_t(17)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "17")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIxFAST8, uint_fast8_t(0x2a)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "2a")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIXFAST8, uint_fast8_t(0xCD)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "CD")); +} + +static void +TestPrintUnsignedFast16() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIoFAST16, uint_fast16_t(04242)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "4242")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIuFAST16, uint_fast16_t(1717)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "1717")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIxFAST16, uint_fast16_t(0x2a2a)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "2a2a")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIXFAST16, uint_fast16_t(0xCDCD)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "CDCD")); +} + +static void +TestPrintUnsignedFast32() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIoFAST32, uint_fast32_t(0424242)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "424242")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIuFAST32, uint_fast32_t(171717)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "171717")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIxFAST32, uint_fast32_t(0x2a2a2a)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "2a2a2a")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIXFAST32, uint_fast32_t(0xCDCDCD)); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "CDCDCD")); +} + +static void +TestPrintUnsignedFast64() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIoFAST64, uint_fast64_t(UINT64_C(0424242424242))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "424242424242")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIuFAST64, + uint_fast64_t(UINT64_C(17171717171717171717))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "17171717171717171717")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIxFAST64, uint_fast64_t(UINT64_C(0x2a2a2a2a2a2a2a))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "2a2a2a2a2a2a2a")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIXFAST64, uint_fast64_t(UINT64_C(0xCDCDCDCDCDCD))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "CDCDCDCDCDCD")); +} + +static void +TestPrintUnsignedFastN() +{ + TestPrintUnsignedFast8(); + TestPrintUnsignedFast16(); + TestPrintUnsignedFast32(); + TestPrintUnsignedFast64(); +} + +static void +TestPrintUnsignedMax() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIoMAX, uintmax_t(UINTMAX_C(432157943248732))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "14220563454333534")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIuMAX, uintmax_t(UINTMAX_C(325719232983))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "325719232983")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIxMAX, uintmax_t(UINTMAX_C(327281321873))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "4c337ca791")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIXMAX, uintmax_t(UINTMAX_C(912389523743523))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "33DD03D75A323")); +} + +static void +TestPrintUnsignedPtr() +{ + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIoPTR, uintptr_t(reinterpret_cast<void*>(12345678))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "57060516")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIuPTR, uintptr_t(reinterpret_cast<void*>(87654321))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "87654321")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIxPTR, uintptr_t(reinterpret_cast<void*>(0x4c3a791))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "4c3a791")); + + PoisonOutput(); + SprintfLiteral(gOutput, "%" PRIXPTR, uintptr_t(reinterpret_cast<void*>(0xF328DB))); + MOZ_RELEASE_ASSERT(!strcmp(gOutput, "F328DB")); +} + +static void +TestPrintUnsigned() +{ + TestPrintUnsignedN(); + TestPrintUnsignedLeastN(); + TestPrintUnsignedFastN(); + TestPrintUnsignedMax(); + TestPrintUnsignedPtr(); +} + +static void +TestPrint() +{ + TestPrintSigned(); + TestPrintUnsigned(); +} + +/* + * The fscanf macros for signed integers are: + * + * SCNdN SCNdLEASTN SCNdFASTN SCNdMAX SCNdPTR + * SCNiN SCNiLEASTN SCNiFASTN SCNiMAX SCNiPTR + * + * In these names N is the width of the type as described in C99 7.18.1. + */ + +/* + * MSVC's scanf is insufficiently powerful to implement all the SCN* macros. + * Rather than support some subset of them, we instead support none of them. + * See the comment at the top of IntegerPrintfMacros.h. But in case we ever do + * support them, the following tests should adequately test implementation + * correctness. (Indeed, these tests *revealed* MSVC's limitations.) + * + * That said, even if MSVC ever picks up complete support, we still probably + * don't want to support these, because of the undefined-behavior issue noted + * further down in the comment atop IntegerPrintfMacros.h. + */ +#define SHOULD_TEST_SCANF_MACROS 0 + +#if SHOULD_TEST_SCANF_MACROS + +/* + * glibc header definitions for SCN{d,i,o,u,x}{,LEAST,FAST}8 use the "hh" length + * modifier, which is new in C99 (and C++11, by reference). We compile this + * file as C++11, so if "hh" is used in these macros, it's standard. But some + * versions of gcc wrongly think it isn't and warn about a "non-standard" + * modifier. And since these tests mostly exist to verify format-macro/type + * consistency (particularly through compiler warnings about incorrect formats), + * these warnings are unacceptable. So for now, compile tests for those macros + * only if we aren't compiling with gcc. + */ +#define SHOULD_TEST_8BIT_FORMAT_MACROS (!(MOZ_IS_GCC)) + +template<typename T> +union Input +{ + T mI; + unsigned char mPun[16]; +}; + +template<typename T> +static void +PoisonInput(Input<T>& aInput) +{ + memset(aInput.mPun, 0xDA, sizeof(aInput.mPun)); +} + +template<typename T> +static bool +ExtraBitsUntouched(const Input<T>& aInput) +{ + for (size_t i = sizeof(aInput.mI); i < sizeof(aInput); i++) { + if (aInput.mPun[i] != 0xDA) { + return false; + } + } + + return true; +} + +static void +TestScanSigned8() +{ +#if SHOULD_TEST_8BIT_FORMAT_MACROS + Input<int8_t> u; + + PoisonInput(u); + sscanf("-17", "%" SCNd8, &u.i); + MOZ_RELEASE_ASSERT(u.i == -17); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("042", "%" SCNi8, &u.i); + MOZ_RELEASE_ASSERT(u.i == 042); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +#endif +} + +static void +TestScanSigned16() +{ + Input<int16_t> u; + + PoisonInput(u); + sscanf("-1742", "%" SCNd16, &u.i); + MOZ_RELEASE_ASSERT(u.i == -1742); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("04217", "%" SCNi16, &u.i); + MOZ_RELEASE_ASSERT(u.i == 04217); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanSigned32() +{ + Input<int32_t> u; + + PoisonInput(u); + sscanf("-174257", "%" SCNd32, &u.i); + MOZ_RELEASE_ASSERT(u.i == -174257); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("0423571", "%" SCNi32, &u.i); + MOZ_RELEASE_ASSERT(u.i == 0423571); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanSigned64() +{ + Input<int64_t> u; + + PoisonInput(u); + sscanf("-17425238927232", "%" SCNd64, &u.i); + MOZ_RELEASE_ASSERT(u.i == -INT64_C(17425238927232)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("042333576571", "%" SCNi64, &u.i); + MOZ_RELEASE_ASSERT(u.i == INT64_C(042333576571)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanSignedN() +{ + TestScanSigned8(); + TestScanSigned16(); + TestScanSigned32(); + TestScanSigned64(); +} + +static void +TestScanSignedLeast8() +{ +#if SHOULD_TEST_8BIT_FORMAT_MACROS + Input<int_least8_t> u; + + PoisonInput(u); + sscanf("-17", "%" SCNdLEAST8, &u.i); + MOZ_RELEASE_ASSERT(u.i == -17); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("042", "%" SCNiLEAST8, &u.i); + MOZ_RELEASE_ASSERT(u.i == 042); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +#endif +} + +static void +TestScanSignedLeast16() +{ + Input<int_least16_t> u; + + PoisonInput(u); + sscanf("-1742", "%" SCNdLEAST16, &u.i); + MOZ_RELEASE_ASSERT(u.i == -1742); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("04217", "%" SCNiLEAST16, &u.i); + MOZ_RELEASE_ASSERT(u.i == 04217); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanSignedLeast32() +{ + Input<int_least32_t> u; + + PoisonInput(u); + sscanf("-174257", "%" SCNdLEAST32, &u.i); + MOZ_RELEASE_ASSERT(u.i == -174257); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("0423571", "%" SCNiLEAST32, &u.i); + MOZ_RELEASE_ASSERT(u.i == 0423571); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanSignedLeast64() +{ + Input<int_least64_t> u; + + PoisonInput(u); + sscanf("-17425238927232", "%" SCNdLEAST64, &u.i); + MOZ_RELEASE_ASSERT(u.i == -INT64_C(17425238927232)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("042333576571", "%" SCNiLEAST64, &u.i); + MOZ_RELEASE_ASSERT(u.i == INT64_C(042333576571)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanSignedLeastN() +{ + TestScanSignedLeast8(); + TestScanSignedLeast16(); + TestScanSignedLeast32(); + TestScanSignedLeast64(); +} + +static void +TestScanSignedFast8() +{ +#if SHOULD_TEST_8BIT_FORMAT_MACROS + Input<int_fast8_t> u; + + PoisonInput(u); + sscanf("-17", "%" SCNdFAST8, &u.i); + MOZ_RELEASE_ASSERT(u.i == -17); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("042", "%" SCNiFAST8, &u.i); + MOZ_RELEASE_ASSERT(u.i == 042); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +#endif +} + +static void +TestScanSignedFast16() +{ + Input<int_fast16_t> u; + + PoisonInput(u); + sscanf("-1742", "%" SCNdFAST16, &u.i); + MOZ_RELEASE_ASSERT(u.i == -1742); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("04217", "%" SCNiFAST16, &u.i); + MOZ_RELEASE_ASSERT(u.i == 04217); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanSignedFast32() +{ + Input<int_fast32_t> u; + + PoisonInput(u); + sscanf("-174257", "%" SCNdFAST32, &u.i); + MOZ_RELEASE_ASSERT(u.i == -174257); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("0423571", "%" SCNiFAST32, &u.i); + MOZ_RELEASE_ASSERT(u.i == 0423571); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanSignedFast64() +{ + Input<int_fast64_t> u; + + PoisonInput(u); + sscanf("-17425238927232", "%" SCNdFAST64, &u.i); + MOZ_RELEASE_ASSERT(u.i == -INT64_C(17425238927232)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("042333576571", "%" SCNiFAST64, &u.i); + MOZ_RELEASE_ASSERT(u.i == INT64_C(042333576571)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanSignedFastN() +{ + TestScanSignedFast8(); + TestScanSignedFast16(); + TestScanSignedFast32(); + TestScanSignedFast64(); +} + +static void +TestScanSignedMax() +{ + Input<intmax_t> u; + + PoisonInput(u); + sscanf("-432157943248732", "%" SCNdMAX, &u.i); + MOZ_RELEASE_ASSERT(u.i == -INTMAX_C(432157943248732)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("04233357236571", "%" SCNiMAX, &u.i); + MOZ_RELEASE_ASSERT(u.i == INTMAX_C(04233357236571)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanSignedPtr() +{ + Input<intptr_t> u; + + PoisonInput(u); + sscanf("12345678", "%" SCNdPTR, &u.i); + MOZ_RELEASE_ASSERT(u.i == intptr_t(reinterpret_cast<void*>(12345678))); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("04233357236", "%" SCNiPTR, &u.i); + MOZ_RELEASE_ASSERT(u.i == intptr_t(reinterpret_cast<void*>(04233357236))); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanSigned() +{ + TestScanSignedN(); + TestScanSignedLeastN(); + TestScanSignedFastN(); + TestScanSignedMax(); + TestScanSignedPtr(); +} + +/* + * The fscanf macros for unsigned integers are: + * + * SCNoN SCNoLEASTN SCNoFASTN SCNoMAX SCNoPTR + * SCNuN SCNuLEASTN SCNuFASTN SCNuMAX SCNuPTR + * SCNxN SCNxLEASTN SCNxFASTN SCNxMAX SCNxPTR + * + * In these names N is the width of the type as described in C99 7.18.1. + */ + +static void +TestScanUnsigned8() +{ +#if SHOULD_TEST_8BIT_FORMAT_MACROS + Input<uint8_t> u; + + PoisonInput(u); + sscanf("17", "%" SCNo8, &u.i); + MOZ_RELEASE_ASSERT(u.i == 017); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("42", "%" SCNu8, &u.i); + MOZ_RELEASE_ASSERT(u.i == 42); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("2A", "%" SCNx8, &u.i); + MOZ_RELEASE_ASSERT(u.i == 0x2A); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +#endif +} + +static void +TestScanUnsigned16() +{ + Input<uint16_t> u; + + PoisonInput(u); + sscanf("1742", "%" SCNo16, &u.i); + MOZ_RELEASE_ASSERT(u.i == 01742); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("4217", "%" SCNu16, &u.i); + MOZ_RELEASE_ASSERT(u.i == 4217); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("2ABC", "%" SCNx16, &u.i); + MOZ_RELEASE_ASSERT(u.i == 0x2ABC); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanUnsigned32() +{ + Input<uint32_t> u; + + PoisonInput(u); + sscanf("17421742", "%" SCNo32, &u.i); + MOZ_RELEASE_ASSERT(u.i == 017421742); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("4217867", "%" SCNu32, &u.i); + MOZ_RELEASE_ASSERT(u.i == 4217867); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("2ABCBEEF", "%" SCNx32, &u.i); + MOZ_RELEASE_ASSERT(u.i == 0x2ABCBEEF); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanUnsigned64() +{ + Input<uint64_t> u; + + PoisonInput(u); + sscanf("17421742173", "%" SCNo64, &u.i); + MOZ_RELEASE_ASSERT(u.i == UINT64_C(017421742173)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("421786713579", "%" SCNu64, &u.i); + MOZ_RELEASE_ASSERT(u.i == UINT64_C(421786713579)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("DEADBEEF7457E", "%" SCNx64, &u.i); + MOZ_RELEASE_ASSERT(u.i == UINT64_C(0xDEADBEEF7457E)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanUnsignedN() +{ + TestScanUnsigned8(); + TestScanUnsigned16(); + TestScanUnsigned32(); + TestScanUnsigned64(); +} + +static void +TestScanUnsignedLeast8() +{ +#if SHOULD_TEST_8BIT_FORMAT_MACROS + Input<uint_least8_t> u; + + PoisonInput(u); + sscanf("17", "%" SCNoLEAST8, &u.i); + MOZ_RELEASE_ASSERT(u.i == 017); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("42", "%" SCNuLEAST8, &u.i); + MOZ_RELEASE_ASSERT(u.i == 42); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("2A", "%" SCNxLEAST8, &u.i); + MOZ_RELEASE_ASSERT(u.i == 0x2A); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +#endif +} + +static void +TestScanUnsignedLeast16() +{ + Input<uint_least16_t> u; + + PoisonInput(u); + sscanf("1742", "%" SCNoLEAST16, &u.i); + MOZ_RELEASE_ASSERT(u.i == 01742); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("4217", "%" SCNuLEAST16, &u.i); + MOZ_RELEASE_ASSERT(u.i == 4217); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("2ABC", "%" SCNxLEAST16, &u.i); + MOZ_RELEASE_ASSERT(u.i == 0x2ABC); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanUnsignedLeast32() +{ + Input<uint_least32_t> u; + + PoisonInput(u); + sscanf("17421742", "%" SCNoLEAST32, &u.i); + MOZ_RELEASE_ASSERT(u.i == 017421742); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("4217867", "%" SCNuLEAST32, &u.i); + MOZ_RELEASE_ASSERT(u.i == 4217867); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("2ABCBEEF", "%" SCNxLEAST32, &u.i); + MOZ_RELEASE_ASSERT(u.i == 0x2ABCBEEF); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanUnsignedLeast64() +{ + Input<uint_least64_t> u; + + PoisonInput(u); + sscanf("17421742173", "%" SCNoLEAST64, &u.i); + MOZ_RELEASE_ASSERT(u.i == UINT64_C(017421742173)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("421786713579", "%" SCNuLEAST64, &u.i); + MOZ_RELEASE_ASSERT(u.i == UINT64_C(421786713579)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("DEADBEEF7457E", "%" SCNxLEAST64, &u.i); + MOZ_RELEASE_ASSERT(u.i == UINT64_C(0xDEADBEEF7457E)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanUnsignedLeastN() +{ + TestScanUnsignedLeast8(); + TestScanUnsignedLeast16(); + TestScanUnsignedLeast32(); + TestScanUnsignedLeast64(); +} + +static void +TestScanUnsignedFast8() +{ +#if SHOULD_TEST_8BIT_FORMAT_MACROS + Input<uint_fast8_t> u; + + PoisonInput(u); + sscanf("17", "%" SCNoFAST8, &u.i); + MOZ_RELEASE_ASSERT(u.i == 017); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("42", "%" SCNuFAST8, &u.i); + MOZ_RELEASE_ASSERT(u.i == 42); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("2A", "%" SCNxFAST8, &u.i); + MOZ_RELEASE_ASSERT(u.i == 0x2A); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +#endif +} + +static void +TestScanUnsignedFast16() +{ + Input<uint_fast16_t> u; + + PoisonInput(u); + sscanf("1742", "%" SCNoFAST16, &u.i); + MOZ_RELEASE_ASSERT(u.i == 01742); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("4217", "%" SCNuFAST16, &u.i); + MOZ_RELEASE_ASSERT(u.i == 4217); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("2ABC", "%" SCNxFAST16, &u.i); + MOZ_RELEASE_ASSERT(u.i == 0x2ABC); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanUnsignedFast32() +{ + Input<uint_fast32_t> u; + + PoisonInput(u); + sscanf("17421742", "%" SCNoFAST32, &u.i); + MOZ_RELEASE_ASSERT(u.i == 017421742); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("4217867", "%" SCNuFAST32, &u.i); + MOZ_RELEASE_ASSERT(u.i == 4217867); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("2ABCBEEF", "%" SCNxFAST32, &u.i); + MOZ_RELEASE_ASSERT(u.i == 0x2ABCBEEF); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanUnsignedFast64() +{ + Input<uint_fast64_t> u; + + PoisonInput(u); + sscanf("17421742173", "%" SCNoFAST64, &u.i); + MOZ_RELEASE_ASSERT(u.i == UINT64_C(017421742173)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("421786713579", "%" SCNuFAST64, &u.i); + MOZ_RELEASE_ASSERT(u.i == UINT64_C(421786713579)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("DEADBEEF7457E", "%" SCNxFAST64, &u.i); + MOZ_RELEASE_ASSERT(u.i == UINT64_C(0xDEADBEEF7457E)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanUnsignedFastN() +{ + TestScanUnsignedFast8(); + TestScanUnsignedFast16(); + TestScanUnsignedFast32(); + TestScanUnsignedFast64(); +} + +static void +TestScanUnsignedMax() +{ + Input<uintmax_t> u; + + PoisonInput(u); + sscanf("14220563454333534", "%" SCNoMAX, &u.i); + MOZ_RELEASE_ASSERT(u.i == UINTMAX_C(432157943248732)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("432157943248732", "%" SCNuMAX, &u.i); + MOZ_RELEASE_ASSERT(u.i == UINTMAX_C(432157943248732)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("4c337ca791", "%" SCNxMAX, &u.i); + MOZ_RELEASE_ASSERT(u.i == UINTMAX_C(327281321873)); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanUnsignedPtr() +{ + Input<uintptr_t> u; + + PoisonInput(u); + sscanf("57060516", "%" SCNoPTR, &u.i); + MOZ_RELEASE_ASSERT(u.i == uintptr_t(reinterpret_cast<void*>(12345678))); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("87654321", "%" SCNuPTR, &u.i); + MOZ_RELEASE_ASSERT(u.i == uintptr_t(reinterpret_cast<void*>(87654321))); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); + + PoisonInput(u); + sscanf("4c3a791", "%" SCNxPTR, &u.i); + MOZ_RELEASE_ASSERT(u.i == uintptr_t(reinterpret_cast<void*>(0x4c3a791))); + MOZ_RELEASE_ASSERT(ExtraBitsUntouched(u)); +} + +static void +TestScanUnsigned() +{ + TestScanUnsignedN(); + TestScanUnsignedLeastN(); + TestScanUnsignedFastN(); + TestScanUnsignedMax(); + TestScanUnsignedPtr(); +} + +static void +TestScan() +{ + TestScanSigned(); + TestScanUnsigned(); +} + +#endif /* SHOULD_TEST_SCANF_MACROS */ + +int +main() +{ + TestPrint(); +#if SHOULD_TEST_SCANF_MACROS + TestScan(); +#endif + return 0; +} diff --git a/mfbt/tests/TestIntegerRange.cpp b/mfbt/tests/TestIntegerRange.cpp new file mode 100644 index 000000000..c2691a26c --- /dev/null +++ b/mfbt/tests/TestIntegerRange.cpp @@ -0,0 +1,163 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/IntegerRange.h" + +#include <stddef.h> + +using mozilla::IsSame; +using mozilla::MakeRange; +using mozilla::Reversed; + +const size_t kMaxNumber = 50; +const size_t kArraySize = 256; + +template<typename IntType> +static IntType +GenerateNumber() +{ + return static_cast<IntType>(rand() % kMaxNumber + 1); +} + +template<typename IntType> +static void +TestSingleParamRange(const IntType aN) +{ + IntType array[kArraySize]; + IntType* ptr = array; + for (auto i : MakeRange(aN)) { + static_assert(IsSame<decltype(i), IntType>::value, + "type of the loop var and the param should be the same"); + *ptr++ = i; + } + + MOZ_RELEASE_ASSERT(ptr - array == static_cast<ptrdiff_t>(aN), + "Should iterates N items"); + for (size_t i = 0; i < static_cast<size_t>(aN); i++) { + MOZ_RELEASE_ASSERT(array[i] == static_cast<IntType>(i), + "Values should equal to the index"); + } +} + +template<typename IntType> +static void +TestSingleParamReverseRange(const IntType aN) +{ + IntType array[kArraySize]; + IntType* ptr = array; + for (auto i : Reversed(MakeRange(aN))) { + static_assert(IsSame<decltype(i), IntType>::value, + "type of the loop var and the param should be the same"); + *ptr++ = i; + } + + MOZ_RELEASE_ASSERT(ptr - array == static_cast<ptrdiff_t>(aN), + "Should iterates N items"); + for (size_t i = 0; i < static_cast<size_t>(aN); i++) { + MOZ_RELEASE_ASSERT(array[i] == static_cast<IntType>(aN - i - 1), + "Values should be the reverse of their index"); + } +} + +template<typename IntType> +static void +TestSingleParamIntegerRange() +{ + const auto kN = GenerateNumber<IntType>(); + TestSingleParamRange<IntType>(0); + TestSingleParamReverseRange<IntType>(0); + TestSingleParamRange<IntType>(kN); + TestSingleParamReverseRange<IntType>(kN); +} + +template<typename IntType1, typename IntType2> +static void +TestDoubleParamRange(const IntType1 aBegin, const IntType2 aEnd) +{ + IntType2 array[kArraySize]; + IntType2* ptr = array; + for (auto i : MakeRange(aBegin, aEnd)) { + static_assert(IsSame<decltype(i), IntType2>::value, "type of the loop var " + "should be same as that of the second param"); + *ptr++ = i; + } + + MOZ_RELEASE_ASSERT(ptr - array == static_cast<ptrdiff_t>(aEnd - aBegin), + "Should iterates (aEnd - aBegin) times"); + for (size_t i = 0; i < static_cast<size_t>(aEnd - aBegin); i++) { + MOZ_RELEASE_ASSERT(array[i] == static_cast<IntType2>(aBegin + i), + "Should iterate integers in [aBegin, aEnd) in order"); + } +} + +template<typename IntType1, typename IntType2> +static void +TestDoubleParamReverseRange(const IntType1 aBegin, const IntType2 aEnd) +{ + IntType2 array[kArraySize]; + IntType2* ptr = array; + for (auto i : Reversed(MakeRange(aBegin, aEnd))) { + static_assert(IsSame<decltype(i), IntType2>::value, "type of the loop var " + "should be same as that of the second param"); + *ptr++ = i; + } + + MOZ_RELEASE_ASSERT(ptr - array == static_cast<ptrdiff_t>(aEnd - aBegin), + "Should iterates (aEnd - aBegin) times"); + for (size_t i = 0; i < static_cast<size_t>(aEnd - aBegin); i++) { + MOZ_RELEASE_ASSERT(array[i] == static_cast<IntType2>(aEnd - i - 1), + "Should iterate integers in [aBegin, aEnd) in reverse order"); + } +} + +template<typename IntType1, typename IntType2> +static void +TestDoubleParamIntegerRange() +{ + const auto kStart = GenerateNumber<IntType1>(); + const auto kEnd = static_cast<IntType2>(kStart + GenerateNumber<IntType2>()); + TestDoubleParamRange(kStart, static_cast<IntType2>(kStart)); + TestDoubleParamReverseRange(kStart, static_cast<IntType2>(kStart)); + TestDoubleParamRange(kStart, kEnd); + TestDoubleParamReverseRange(kStart, kEnd); +} + +int +main() +{ + TestSingleParamIntegerRange<int8_t>(); + TestSingleParamIntegerRange<int16_t>(); + TestSingleParamIntegerRange<int32_t>(); + TestSingleParamIntegerRange<int64_t>(); + + TestSingleParamIntegerRange<uint8_t>(); + TestSingleParamIntegerRange<uint16_t>(); + TestSingleParamIntegerRange<uint32_t>(); + TestSingleParamIntegerRange<uint64_t>(); + + TestDoubleParamIntegerRange<int8_t, int8_t>(); + TestDoubleParamIntegerRange<int16_t, int16_t>(); + TestDoubleParamIntegerRange<int32_t, int32_t>(); + TestDoubleParamIntegerRange<int64_t, int64_t>(); + + TestDoubleParamIntegerRange<uint8_t, uint8_t>(); + TestDoubleParamIntegerRange<uint16_t, uint16_t>(); + TestDoubleParamIntegerRange<uint32_t, uint32_t>(); + TestDoubleParamIntegerRange<uint64_t, uint64_t>(); + + TestDoubleParamIntegerRange<int8_t, int16_t>(); + TestDoubleParamIntegerRange<int16_t, int32_t>(); + TestDoubleParamIntegerRange<int32_t, int64_t>(); + TestDoubleParamIntegerRange<int64_t, int8_t>(); + + TestDoubleParamIntegerRange<uint8_t, uint64_t>(); + TestDoubleParamIntegerRange<uint16_t, uint8_t>(); + TestDoubleParamIntegerRange<uint32_t, uint16_t>(); + TestDoubleParamIntegerRange<uint64_t, uint32_t>(); + + return 0; +} diff --git a/mfbt/tests/TestJSONWriter.cpp b/mfbt/tests/TestJSONWriter.cpp new file mode 100644 index 000000000..6c081d170 --- /dev/null +++ b/mfbt/tests/TestJSONWriter.cpp @@ -0,0 +1,539 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/JSONWriter.h" +#include "mozilla/UniquePtr.h" +#include <stdio.h> +#include <string.h> + +using mozilla::JSONWriteFunc; +using mozilla::JSONWriter; +using mozilla::MakeUnique; + +// This writes all the output into a big buffer. +struct StringWriteFunc : public JSONWriteFunc +{ + const static size_t kLen = 100000; + char mBuf[kLen]; + char* mPtr; + + StringWriteFunc() : mPtr(mBuf) {} + + void Write(const char* aStr) + { + char* last = mPtr + strlen(aStr); // where the nul will be added + + // If you change this test and this assertion fails, just make kLen bigger. + MOZ_RELEASE_ASSERT(last < mBuf + kLen); + sprintf(mPtr, "%s", aStr); + mPtr = last; + } +}; + +void Check(JSONWriteFunc* aFunc, const char* aExpected) +{ + const char* actual = static_cast<StringWriteFunc*>(aFunc)->mBuf; + if (strcmp(aExpected, actual) != 0) { + fprintf(stderr, + "---- EXPECTED ----\n<<<%s>>>\n" + "---- ACTUAL ----\n<<<%s>>>\n", + aExpected, actual); + MOZ_RELEASE_ASSERT(false, "expected and actual output don't match"); + } +} + +// Note: to convert actual output into |expected| strings that C++ can handle, +// apply the following substitutions, in order, to each line. +// - s/\\/\\\\/g # escapes backslashes +// - s/"/\\"/g # escapes quotes +// - s/$/\\n\\/ # adds a newline and string continuation char to each line + +void TestBasicProperties() +{ + const char* expected = "\ +{\n\ + \"null\": null,\n\ + \"bool1\": true,\n\ + \"bool2\": false,\n\ + \"int1\": 123,\n\ + \"int2\": -123,\n\ + \"int3\": -123456789000,\n\ + \"double1\": 1.2345,\n\ + \"double2\": -3,\n\ + \"double3\": 1e-7,\n\ + \"double4\": 1.1111111111111111e+21,\n\ + \"string1\": \"\",\n\ + \"string2\": \"1234\",\n\ + \"string3\": \"hello\",\n\ + \"string4\": \"\\\" \\\\ \\u0007 \\b \\t \\n \\u000b \\f \\r\",\n\ + \"len 0 array, multi-line\": [\n\ + ],\n\ + \"len 0 array, single-line\": [],\n\ + \"len 1 array\": [\n\ + 1\n\ + ],\n\ + \"len 5 array, multi-line\": [\n\ + 1,\n\ + 2,\n\ + 3,\n\ + 4,\n\ + 5\n\ + ],\n\ + \"len 3 array, single-line\": [1, [{}, 2, []], 3],\n\ + \"len 0 object, multi-line\": {\n\ + },\n\ + \"len 0 object, single-line\": {},\n\ + \"len 1 object\": {\n\ + \"one\": 1\n\ + },\n\ + \"len 5 object\": {\n\ + \"one\": 1,\n\ + \"two\": 2,\n\ + \"three\": 3,\n\ + \"four\": 4,\n\ + \"five\": 5\n\ + },\n\ + \"len 3 object, single-line\": {\"a\": 1, \"b\": [{}, 2, []], \"c\": 3}\n\ +}\n\ +"; + + JSONWriter w(MakeUnique<StringWriteFunc>()); + + w.Start(); + { + w.NullProperty("null"); + + w.BoolProperty("bool1", true); + w.BoolProperty("bool2", false); + + w.IntProperty("int1", 123); + w.IntProperty("int2", -0x7b); + w.IntProperty("int3", -123456789000ll); + + w.DoubleProperty("double1", 1.2345); + w.DoubleProperty("double2", -3); + w.DoubleProperty("double3", 1e-7); + w.DoubleProperty("double4", 1.1111111111111111e+21); + + w.StringProperty("string1", ""); + w.StringProperty("string2", "1234"); + w.StringProperty("string3", "hello"); + w.StringProperty("string4", "\" \\ \a \b \t \n \v \f \r"); + + w.StartArrayProperty("len 0 array, multi-line", w.MultiLineStyle); + w.EndArray(); + + w.StartArrayProperty("len 0 array, single-line", w.SingleLineStyle); + w.EndArray(); + + w.StartArrayProperty("len 1 array"); + { + w.IntElement(1); + } + w.EndArray(); + + w.StartArrayProperty("len 5 array, multi-line", w.MultiLineStyle); + { + w.IntElement(1); + w.IntElement(2); + w.IntElement(3); + w.IntElement(4); + w.IntElement(5); + } + w.EndArray(); + + w.StartArrayProperty("len 3 array, single-line", w.SingleLineStyle); + { + w.IntElement(1); + w.StartArrayElement(); + { + w.StartObjectElement(w.SingleLineStyle); + w.EndObject(); + + w.IntElement(2); + + w.StartArrayElement(w.MultiLineStyle); // style overridden from above + w.EndArray(); + } + w.EndArray(); + w.IntElement(3); + } + w.EndArray(); + + w.StartObjectProperty("len 0 object, multi-line"); + w.EndObject(); + + w.StartObjectProperty("len 0 object, single-line", w.SingleLineStyle); + w.EndObject(); + + w.StartObjectProperty("len 1 object"); + { + w.IntProperty("one", 1); + } + w.EndObject(); + + w.StartObjectProperty("len 5 object"); + { + w.IntProperty("one", 1); + w.IntProperty("two", 2); + w.IntProperty("three", 3); + w.IntProperty("four", 4); + w.IntProperty("five", 5); + } + w.EndObject(); + + w.StartObjectProperty("len 3 object, single-line", w.SingleLineStyle); + { + w.IntProperty("a", 1); + w.StartArrayProperty("b"); + { + w.StartObjectElement(); + w.EndObject(); + + w.IntElement(2); + + w.StartArrayElement(w.SingleLineStyle); + w.EndArray(); + } + w.EndArray(); + w.IntProperty("c", 3); + } + w.EndObject(); + } + w.End(); + + Check(w.WriteFunc(), expected); +} + +void TestBasicElements() +{ + const char* expected = "\ +{\n\ + \"array\": [\n\ + null,\n\ + true,\n\ + false,\n\ + 123,\n\ + -123,\n\ + -123456789000,\n\ + 1.2345,\n\ + -3,\n\ + 1e-7,\n\ + 1.1111111111111111e+21,\n\ + \"\",\n\ + \"1234\",\n\ + \"hello\",\n\ + \"\\\" \\\\ \\u0007 \\b \\t \\n \\u000b \\f \\r\",\n\ + [\n\ + ],\n\ + [],\n\ + [\n\ + 1\n\ + ],\n\ + [\n\ + 1,\n\ + 2,\n\ + 3,\n\ + 4,\n\ + 5\n\ + ],\n\ + [1, [{}, 2, []], 3],\n\ + {\n\ + },\n\ + {},\n\ + {\n\ + \"one\": 1\n\ + },\n\ + {\n\ + \"one\": 1,\n\ + \"two\": 2,\n\ + \"three\": 3,\n\ + \"four\": 4,\n\ + \"five\": 5\n\ + },\n\ + {\"a\": 1, \"b\": [{}, 2, []], \"c\": 3}\n\ + ]\n\ +}\n\ +"; + + JSONWriter w(MakeUnique<StringWriteFunc>()); + + w.Start(); + w.StartArrayProperty("array"); + { + w.NullElement(); + + w.BoolElement(true); + w.BoolElement(false); + + w.IntElement(123); + w.IntElement(-0x7b); + w.IntElement(-123456789000ll); + + w.DoubleElement(1.2345); + w.DoubleElement(-3); + w.DoubleElement(1e-7); + w.DoubleElement(1.1111111111111111e+21); + + w.StringElement(""); + w.StringElement("1234"); + w.StringElement("hello"); + w.StringElement("\" \\ \a \b \t \n \v \f \r"); + + w.StartArrayElement(); + w.EndArray(); + + w.StartArrayElement(w.SingleLineStyle); + w.EndArray(); + + w.StartArrayElement(); + { + w.IntElement(1); + } + w.EndArray(); + + w.StartArrayElement(); + { + w.IntElement(1); + w.IntElement(2); + w.IntElement(3); + w.IntElement(4); + w.IntElement(5); + } + w.EndArray(); + + w.StartArrayElement(w.SingleLineStyle); + { + w.IntElement(1); + w.StartArrayElement(); + { + w.StartObjectElement(w.SingleLineStyle); + w.EndObject(); + + w.IntElement(2); + + w.StartArrayElement(w.MultiLineStyle); // style overridden from above + w.EndArray(); + } + w.EndArray(); + w.IntElement(3); + } + w.EndArray(); + + w.StartObjectElement(); + w.EndObject(); + + w.StartObjectElement(w.SingleLineStyle); + w.EndObject(); + + w.StartObjectElement(); + { + w.IntProperty("one", 1); + } + w.EndObject(); + + w.StartObjectElement(); + { + w.IntProperty("one", 1); + w.IntProperty("two", 2); + w.IntProperty("three", 3); + w.IntProperty("four", 4); + w.IntProperty("five", 5); + } + w.EndObject(); + + w.StartObjectElement(w.SingleLineStyle); + { + w.IntProperty("a", 1); + w.StartArrayProperty("b"); + { + w.StartObjectElement(); + w.EndObject(); + + w.IntElement(2); + + w.StartArrayElement(w.SingleLineStyle); + w.EndArray(); + } + w.EndArray(); + w.IntProperty("c", 3); + } + w.EndObject(); + } + w.EndArray(); + w.End(); + + Check(w.WriteFunc(), expected); +} + +void TestOneLineObject() +{ + const char* expected = "\ +{\"i\": 1, \"array\": [null, [{}], {\"o\": {}}, \"s\"], \"d\": 3.33}\n\ +"; + + JSONWriter w(MakeUnique<StringWriteFunc>()); + + w.Start(w.SingleLineStyle); + + w.IntProperty("i", 1); + + w.StartArrayProperty("array"); + { + w.NullElement(); + + w.StartArrayElement(w.MultiLineStyle); // style overridden from above + { + w.StartObjectElement(); + w.EndObject(); + } + w.EndArray(); + + w.StartObjectElement(); + { + w.StartObjectProperty("o"); + w.EndObject(); + } + w.EndObject(); + + w.StringElement("s"); + } + w.EndArray(); + + w.DoubleProperty("d", 3.33); + + w.End(); + + Check(w.WriteFunc(), expected); +} + +void TestStringEscaping() +{ + // This test uses hexadecimal character escapes because UTF8 literals cause + // problems for some compilers (see bug 1069726). + const char* expected = "\ +{\n\ + \"ascii\": \"\x7F~}|{zyxwvutsrqponmlkjihgfedcba`_^]\\\\[ZYXWVUTSRQPONMLKJIHGFEDCBA@?>=<;:9876543210/.-,+*)('&%$#\\\"! \\u001f\\u001e\\u001d\\u001c\\u001b\\u001a\\u0019\\u0018\\u0017\\u0016\\u0015\\u0014\\u0013\\u0012\\u0011\\u0010\\u000f\\u000e\\r\\f\\u000b\\n\\t\\b\\u0007\\u0006\\u0005\\u0004\\u0003\\u0002\\u0001\",\n\ + \"\xD9\x85\xD8\xB1\xD8\xAD\xD8\xA8\xD8\xA7 \xD9\x87\xD9\x86\xD8\xA7\xD9\x83\": true,\n\ + \"\xD5\xA2\xD5\xA1\xD6\x80\xD5\xA5\xD6\x82 \xD5\xB9\xD5\xAF\xD5\xA1\": -123,\n\ + \"\xE4\xBD\xA0\xE5\xA5\xBD\": 1.234,\n\ + \"\xCE\xB3\xCE\xB5\xCE\xB9\xCE\xB1 \xCE\xB5\xCE\xBA\xCE\xB5\xCE\xAF\": \"\xD8\xB3\xD9\x84\xD8\xA7\xD9\x85\",\n\ + \"hall\xC3\xB3 \xC3\xBE" "arna\": 4660,\n\ + \"\xE3\x81\x93\xE3\x82\x93\xE3\x81\xAB\xE3\x81\xA1\xE3\x81\xAF\": {\n\ + \"\xD0\xBF\xD1\x80\xD0\xB8\xD0\xB2\xD0\xB5\xD1\x82\": [\n\ + ]\n\ + }\n\ +}\n\ +"; + + JSONWriter w(MakeUnique<StringWriteFunc>()); + + // Test the string escaping behaviour. + w.Start(); + { + // Test all 127 ascii values. Do it in reverse order so that the 0 + // at the end serves as the null char. + char buf[128]; + for (int i = 0; i < 128; i++) { + buf[i] = 127 - i; + } + w.StringProperty("ascii", buf); + + // Test lots of unicode stuff. Note that this file is encoded as UTF-8. + w.BoolProperty("\xD9\x85\xD8\xB1\xD8\xAD\xD8\xA8\xD8\xA7 \xD9\x87\xD9\x86\xD8\xA7\xD9\x83", true); + w.IntProperty("\xD5\xA2\xD5\xA1\xD6\x80\xD5\xA5\xD6\x82 \xD5\xB9\xD5\xAF\xD5\xA1", -123); + w.DoubleProperty("\xE4\xBD\xA0\xE5\xA5\xBD", 1.234); + w.StringProperty("\xCE\xB3\xCE\xB5\xCE\xB9\xCE\xB1 \xCE\xB5\xCE\xBA\xCE\xB5\xCE\xAF", "\xD8\xB3\xD9\x84\xD8\xA7\xD9\x85"); + w.IntProperty("hall\xC3\xB3 \xC3\xBE" "arna", 0x1234); + w.StartObjectProperty("\xE3\x81\x93\xE3\x82\x93\xE3\x81\xAB\xE3\x81\xA1\xE3\x81\xAF"); + { + w.StartArrayProperty("\xD0\xBF\xD1\x80\xD0\xB8\xD0\xB2\xD0\xB5\xD1\x82"); + w.EndArray(); + } + w.EndObject(); + } + w.End(); + + Check(w.WriteFunc(), expected); +} + +void TestDeepNesting() +{ + const char* expected = "\ +{\n\ + \"a\": [\n\ + {\n\ + \"a\": [\n\ + {\n\ + \"a\": [\n\ + {\n\ + \"a\": [\n\ + {\n\ + \"a\": [\n\ + {\n\ + \"a\": [\n\ + {\n\ + \"a\": [\n\ + {\n\ + \"a\": [\n\ + {\n\ + \"a\": [\n\ + {\n\ + \"a\": [\n\ + {\n\ + }\n\ + ]\n\ + }\n\ + ]\n\ + }\n\ + ]\n\ + }\n\ + ]\n\ + }\n\ + ]\n\ + }\n\ + ]\n\ + }\n\ + ]\n\ + }\n\ + ]\n\ + }\n\ + ]\n\ + }\n\ + ]\n\ +}\n\ +"; + + JSONWriter w(MakeUnique<StringWriteFunc>()); + + w.Start(); + { + static const int n = 10; + for (int i = 0; i < n; i++) { + w.StartArrayProperty("a"); + w.StartObjectElement(); + } + for (int i = 0; i < n; i++) { + w.EndObject(); + w.EndArray(); + } + } + w.End(); + + Check(w.WriteFunc(), expected); +} + +int main(void) +{ + TestBasicProperties(); + TestBasicElements(); + TestOneLineObject(); + TestStringEscaping(); + TestDeepNesting(); + + return 0; +} diff --git a/mfbt/tests/TestLinkedList.cpp b/mfbt/tests/TestLinkedList.cpp new file mode 100644 index 000000000..0421668b9 --- /dev/null +++ b/mfbt/tests/TestLinkedList.cpp @@ -0,0 +1,268 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/LinkedList.h" + +using mozilla::LinkedList; +using mozilla::LinkedListElement; + +struct SomeClass : public LinkedListElement<SomeClass> { + unsigned int mValue; + explicit SomeClass(int aValue = 0) : mValue(aValue) {} + void incr() { ++mValue; } +}; + +template <size_t N> +static void +CheckListValues(LinkedList<SomeClass>& list, unsigned int (&values)[N]) +{ + size_t count = 0; + for (SomeClass* x : list) { + MOZ_RELEASE_ASSERT(x->mValue == values[count]); + ++count; + } + MOZ_RELEASE_ASSERT(count == N); +} + +static void +TestList() +{ + LinkedList<SomeClass> list; + + SomeClass one(1), two(2), three(3); + + MOZ_RELEASE_ASSERT(list.isEmpty()); + MOZ_RELEASE_ASSERT(!list.getFirst()); + MOZ_RELEASE_ASSERT(!list.getLast()); + MOZ_RELEASE_ASSERT(!list.popFirst()); + MOZ_RELEASE_ASSERT(!list.popLast()); + + for (SomeClass* x : list) { + MOZ_RELEASE_ASSERT(x); + MOZ_RELEASE_ASSERT(false); + } + + list.insertFront(&one); + { unsigned int check[] { 1 }; CheckListValues(list, check); } + + MOZ_RELEASE_ASSERT(one.isInList()); + MOZ_RELEASE_ASSERT(!two.isInList()); + MOZ_RELEASE_ASSERT(!three.isInList()); + + MOZ_RELEASE_ASSERT(!list.isEmpty()); + MOZ_RELEASE_ASSERT(list.getFirst()->mValue == 1); + MOZ_RELEASE_ASSERT(list.getLast()->mValue == 1); + + list.insertFront(&two); + { unsigned int check[] { 2, 1 }; CheckListValues(list, check); } + + MOZ_RELEASE_ASSERT(list.getFirst()->mValue == 2); + MOZ_RELEASE_ASSERT(list.getLast()->mValue == 1); + + list.insertBack(&three); + { unsigned int check[] { 2, 1, 3 }; CheckListValues(list, check); } + + MOZ_RELEASE_ASSERT(list.getFirst()->mValue == 2); + MOZ_RELEASE_ASSERT(list.getLast()->mValue == 3); + + one.removeFrom(list); + { unsigned int check[] { 2, 3 }; CheckListValues(list, check); } + + three.setPrevious(&one); + { unsigned int check[] { 2, 1, 3 }; CheckListValues(list, check); } + + three.removeFrom(list); + { unsigned int check[] { 2, 1 }; CheckListValues(list, check); } + + two.setPrevious(&three); + { unsigned int check[] { 3, 2, 1 }; CheckListValues(list, check); } + + three.removeFrom(list); + { unsigned int check[] { 2, 1 }; CheckListValues(list, check); } + + two.setNext(&three); + { unsigned int check[] { 2, 3, 1 }; CheckListValues(list, check); } + + one.remove(); + { unsigned int check[] { 2, 3 }; CheckListValues(list, check); } + + two.remove(); + { unsigned int check[] { 3 }; CheckListValues(list, check); } + + three.setPrevious(&two); + { unsigned int check[] { 2, 3 }; CheckListValues(list, check); } + + three.remove(); + { unsigned int check[] { 2 }; CheckListValues(list, check); } + + two.remove(); + + list.insertBack(&three); + { unsigned int check[] { 3 }; CheckListValues(list, check); } + + list.insertFront(&two); + { unsigned int check[] { 2, 3 }; CheckListValues(list, check); } + + for (SomeClass* x : list) { + x->incr(); + } + + MOZ_RELEASE_ASSERT(list.getFirst() == &two); + MOZ_RELEASE_ASSERT(list.getLast() == &three); + MOZ_RELEASE_ASSERT(list.getFirst()->mValue == 3); + MOZ_RELEASE_ASSERT(list.getLast()->mValue == 4); +} + +static void +TestMove() +{ + auto MakeSomeClass = + [] (unsigned int aValue) -> SomeClass { return SomeClass(aValue); }; + + LinkedList<SomeClass> list1; + + // Test move constructor for LinkedListElement. + SomeClass c1(MakeSomeClass(1)); + list1.insertBack(&c1); + + // Test move assignment for LinkedListElement from an element not in a + // list. + SomeClass c2; + c2 = MakeSomeClass(2); + list1.insertBack(&c2); + + // Test move assignment of LinkedListElement from an element already in a + // list. + SomeClass c3; + c3 = Move(c2); + MOZ_RELEASE_ASSERT(!c2.isInList()); + MOZ_RELEASE_ASSERT(c3.isInList()); + + // Test move constructor for LinkedList. + LinkedList<SomeClass> list2(Move(list1)); + { unsigned int check[] { 1, 2 }; CheckListValues(list2, check); } + MOZ_RELEASE_ASSERT(list1.isEmpty()); + + // Test move assignment for LinkedList. + LinkedList<SomeClass> list3; + list3 = Move(list2); + { unsigned int check[] { 1, 2 }; CheckListValues(list3, check); } + MOZ_RELEASE_ASSERT(list2.isEmpty()); + + list3.clear(); +} + +static void +TestRemoveAndGet() +{ + LinkedList<SomeClass> list; + + SomeClass one(1), two(2), three(3); + list.insertBack(&one); + list.insertBack(&two); + list.insertBack(&three); + { unsigned int check[] { 1, 2, 3 }; CheckListValues(list, check); } + + MOZ_RELEASE_ASSERT(two.removeAndGetNext() == &three); + { unsigned int check[] { 1, 3 }; CheckListValues(list, check); } + + MOZ_RELEASE_ASSERT(three.removeAndGetPrevious() == &one); + { unsigned int check[] { 1 }; CheckListValues(list, check); } +} + +struct PrivateClass : private LinkedListElement<PrivateClass> { + friend class mozilla::LinkedList<PrivateClass>; + friend class mozilla::LinkedListElement<PrivateClass>; +}; + +static void +TestPrivate() +{ + LinkedList<PrivateClass> list; + PrivateClass one, two; + list.insertBack(&one); + list.insertBack(&two); + + size_t count = 0; + for (PrivateClass* p : list) { + MOZ_RELEASE_ASSERT(p, "cannot have null elements in list"); + count++; + } + MOZ_RELEASE_ASSERT(count == 2); +} + +struct CountedClass : public LinkedListElement<RefPtr<CountedClass>> +{ + int mCount; + void AddRef() { mCount++; } + void Release() { mCount--; } + + CountedClass() : mCount(0) {} + ~CountedClass() { MOZ_RELEASE_ASSERT(mCount == 0); } +}; + +static void +TestRefPtrList() +{ + LinkedList<RefPtr<CountedClass>> list; + CountedClass* elt1 = new CountedClass; + CountedClass* elt2 = new CountedClass; + + list.insertBack(elt1); + list.insertBack(elt2); + + MOZ_RELEASE_ASSERT(elt1->mCount == 1); + MOZ_RELEASE_ASSERT(elt2->mCount == 1); + + for (RefPtr<CountedClass> p : list) { + MOZ_RELEASE_ASSERT(p->mCount == 2); + } + + RefPtr<CountedClass> ptr = list.getFirst(); + while (ptr) { + MOZ_RELEASE_ASSERT(ptr->mCount == 2); + RefPtr<CountedClass> next = ptr->getNext(); + ptr->remove(); + ptr = Move(next); + } + ptr = nullptr; + + MOZ_RELEASE_ASSERT(elt1->mCount == 0); + MOZ_RELEASE_ASSERT(elt2->mCount == 0); + + list.insertBack(elt1); + elt1->setNext(elt2); + + MOZ_RELEASE_ASSERT(elt1->mCount == 1); + MOZ_RELEASE_ASSERT(elt2->mCount == 1); + + RefPtr<CountedClass> first = list.popFirst(); + + MOZ_RELEASE_ASSERT(elt1->mCount == 1); + MOZ_RELEASE_ASSERT(elt2->mCount == 1); + + RefPtr<CountedClass> second = list.popFirst(); + + MOZ_RELEASE_ASSERT(elt1->mCount == 1); + MOZ_RELEASE_ASSERT(elt2->mCount == 1); + + first = second = nullptr; + + delete elt1; + delete elt2; +} + +int +main() +{ + TestList(); + TestPrivate(); + TestMove(); + TestRemoveAndGet(); + TestRefPtrList(); + return 0; +} diff --git a/mfbt/tests/TestMacroArgs.cpp b/mfbt/tests/TestMacroArgs.cpp new file mode 100644 index 000000000..0d9760463 --- /dev/null +++ b/mfbt/tests/TestMacroArgs.cpp @@ -0,0 +1,31 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/MacroArgs.h" + +MOZ_STATIC_ASSERT_VALID_ARG_COUNT(1); +MOZ_STATIC_ASSERT_VALID_ARG_COUNT(1, 2); + +static_assert(MOZ_PASTE_PREFIX_AND_ARG_COUNT(100, a, b, c) == 1003, ""); + +static_assert(MOZ_PASTE_PREFIX_AND_ARG_COUNT(, a, b, c) == 3, ""); +static_assert(MOZ_PASTE_PREFIX_AND_ARG_COUNT(, a) == 1, ""); +static_assert(MOZ_PASTE_PREFIX_AND_ARG_COUNT(, !a) == 1, ""); +static_assert(MOZ_PASTE_PREFIX_AND_ARG_COUNT(, (a, b)) == 1, ""); + +static_assert(MOZ_PASTE_PREFIX_AND_ARG_COUNT(, MOZ_ARGS_AFTER_1(a, b, c)) == 2, + "MOZ_ARGS_AFTER_1(a, b, c) should expand to 'b, c'"); +static_assert(MOZ_ARGS_AFTER_2(a, b, 3) == 3, + "MOZ_ARGS_AFTER_2(a, b, 3) should expand to '3'"); + +static_assert(MOZ_ARG_1(10, 20, 30) == 10, ""); +static_assert(MOZ_ARG_2(10, 20, 30) == 20, ""); + +int +main() +{ + return 0; +} diff --git a/mfbt/tests/TestMacroForEach.cpp b/mfbt/tests/TestMacroForEach.cpp new file mode 100644 index 000000000..04a78d4b3 --- /dev/null +++ b/mfbt/tests/TestMacroForEach.cpp @@ -0,0 +1,35 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/MacroForEach.h" + +#define HELPER_IDENTITY_PLUS(x) x + +static_assert(MOZ_FOR_EACH(HELPER_IDENTITY_PLUS, (), (10)) 0 == 10, ""); +static_assert(MOZ_FOR_EACH(HELPER_IDENTITY_PLUS, (), (1, 1, 1)) 0 == 3, ""); + +#define HELPER_DEFINE_VAR(x) const int test1_##x = x; +MOZ_FOR_EACH(HELPER_DEFINE_VAR, (), (10, 20)) +static_assert(test1_10 == 10 && test1_20 == 20, ""); + +#define HELPER_DEFINE_VAR2(k, x) const int test2_##x = k + x; +MOZ_FOR_EACH(HELPER_DEFINE_VAR2, (5,), (10, 20)) +static_assert(test2_10 == 15 && test2_20 == 25, ""); + +#define HELPER_IDENTITY_COMMA(k1, k2, x) k1, k2, x, + +int +main() +{ + const int a[] = { + MOZ_FOR_EACH(HELPER_IDENTITY_COMMA, (1, 2,), (10, 20, 30)) + }; + MOZ_RELEASE_ASSERT(a[0] == 1 && a[1] == 2 && a[2] == 10 && + a[3] == 1 && a[4] == 2 && a[5] == 20 && + a[6] == 1 && a[7] == 2 && a[8] == 30, + "MOZ_FOR_EACH args enumerated in incorrect order"); + return 0; +} diff --git a/mfbt/tests/TestMathAlgorithms.cpp b/mfbt/tests/TestMathAlgorithms.cpp new file mode 100644 index 000000000..4e2629cba --- /dev/null +++ b/mfbt/tests/TestMathAlgorithms.cpp @@ -0,0 +1,87 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/MathAlgorithms.h" + +using mozilla::Clamp; +using mozilla::IsPowerOfTwo; + +static void +TestClamp() +{ + MOZ_RELEASE_ASSERT(Clamp(0, 0, 0) == 0); + MOZ_RELEASE_ASSERT(Clamp(1, 0, 0) == 0); + MOZ_RELEASE_ASSERT(Clamp(-1, 0, 0) == 0); + + MOZ_RELEASE_ASSERT(Clamp(0, 1, 1) == 1); + MOZ_RELEASE_ASSERT(Clamp(0, 1, 2) == 1); + + MOZ_RELEASE_ASSERT(Clamp(0, -1, -1) == -1); + MOZ_RELEASE_ASSERT(Clamp(0, -2, -1) == -1); + + MOZ_RELEASE_ASSERT(Clamp(0, 1, 3) == 1); + MOZ_RELEASE_ASSERT(Clamp(1, 1, 3) == 1); + MOZ_RELEASE_ASSERT(Clamp(2, 1, 3) == 2); + MOZ_RELEASE_ASSERT(Clamp(3, 1, 3) == 3); + MOZ_RELEASE_ASSERT(Clamp(4, 1, 3) == 3); + MOZ_RELEASE_ASSERT(Clamp(5, 1, 3) == 3); + + MOZ_RELEASE_ASSERT(Clamp<uint8_t>(UINT8_MAX, 0, UINT8_MAX) == UINT8_MAX); + MOZ_RELEASE_ASSERT(Clamp<uint8_t>(0, 0, UINT8_MAX) == 0); + + MOZ_RELEASE_ASSERT(Clamp<int8_t>(INT8_MIN, INT8_MIN, INT8_MAX) == INT8_MIN); + MOZ_RELEASE_ASSERT(Clamp<int8_t>(INT8_MIN, 0, INT8_MAX) == 0); + MOZ_RELEASE_ASSERT(Clamp<int8_t>(INT8_MAX, INT8_MIN, INT8_MAX) == INT8_MAX); + MOZ_RELEASE_ASSERT(Clamp<int8_t>(INT8_MAX, INT8_MIN, 0) == 0); +} + +static void +TestIsPowerOfTwo() +{ + static_assert(!IsPowerOfTwo(0u), "0 isn't a power of two"); + static_assert(IsPowerOfTwo(1u), "1 is a power of two"); + static_assert(IsPowerOfTwo(2u), "2 is a power of two"); + static_assert(!IsPowerOfTwo(3u), "3 isn't a power of two"); + static_assert(IsPowerOfTwo(4u), "4 is a power of two"); + static_assert(!IsPowerOfTwo(5u), "5 isn't a power of two"); + static_assert(!IsPowerOfTwo(6u), "6 isn't a power of two"); + static_assert(!IsPowerOfTwo(7u), "7 isn't a power of two"); + static_assert(IsPowerOfTwo(8u), "8 is a power of two"); + static_assert(!IsPowerOfTwo(9u), "9 isn't a power of two"); + + static_assert(!IsPowerOfTwo(uint8_t(UINT8_MAX/2)), "127, 0x7f isn't a power of two"); + static_assert(IsPowerOfTwo(uint8_t(UINT8_MAX/2 + 1)), "128, 0x80 is a power of two"); + static_assert(!IsPowerOfTwo(uint8_t(UINT8_MAX/2 + 2)), "129, 0x81 isn't a power of two"); + static_assert(!IsPowerOfTwo(uint8_t(UINT8_MAX - 1)), "254, 0xfe isn't a power of two"); + static_assert(!IsPowerOfTwo(uint8_t(UINT8_MAX)), "255, 0xff isn't a power of two"); + + static_assert(!IsPowerOfTwo(uint16_t(UINT16_MAX/2)), "0x7fff isn't a power of two"); + static_assert(IsPowerOfTwo(uint16_t(UINT16_MAX/2 + 1)), "0x8000 is a power of two"); + static_assert(!IsPowerOfTwo(uint16_t(UINT16_MAX/2 + 2)), "0x8001 isn't a power of two"); + static_assert(!IsPowerOfTwo(uint16_t(UINT16_MAX - 1)), "0xfffe isn't a power of two"); + static_assert(!IsPowerOfTwo(uint16_t(UINT16_MAX)), "0xffff isn't a power of two"); + + static_assert(!IsPowerOfTwo(uint32_t(UINT32_MAX/2)), "0x7fffffff isn't a power of two"); + static_assert(IsPowerOfTwo(uint32_t(UINT32_MAX/2 + 1)), "0x80000000 is a power of two"); + static_assert(!IsPowerOfTwo(uint32_t(UINT32_MAX/2 + 2)), "0x80000001 isn't a power of two"); + static_assert(!IsPowerOfTwo(uint32_t(UINT32_MAX - 1)), "0xfffffffe isn't a power of two"); + static_assert(!IsPowerOfTwo(uint32_t(UINT32_MAX)), "0xffffffff isn't a power of two"); + + static_assert(!IsPowerOfTwo(uint64_t(UINT64_MAX/2)), "0x7fffffffffffffff isn't a power of two"); + static_assert(IsPowerOfTwo(uint64_t(UINT64_MAX/2 + 1)), "0x8000000000000000 is a power of two"); + static_assert(!IsPowerOfTwo(uint64_t(UINT64_MAX/2 + 2)), "0x8000000000000001 isn't a power of two"); + static_assert(!IsPowerOfTwo(uint64_t(UINT64_MAX - 1)), "0xfffffffffffffffe isn't a power of two"); + static_assert(!IsPowerOfTwo(uint64_t(UINT64_MAX)), "0xffffffffffffffff isn't a power of two"); +} + +int +main() +{ + TestIsPowerOfTwo(); + TestClamp(); + + return 0; +} diff --git a/mfbt/tests/TestMaybe.cpp b/mfbt/tests/TestMaybe.cpp new file mode 100644 index 000000000..5817ab428 --- /dev/null +++ b/mfbt/tests/TestMaybe.cpp @@ -0,0 +1,860 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include <utility> + +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" +#include "mozilla/Compiler.h" +#include "mozilla/Maybe.h" +#include "mozilla/Move.h" +#include "mozilla/Types.h" +#include "mozilla/TypeTraits.h" +#include "mozilla/UniquePtr.h" + +using mozilla::IsSame; +using mozilla::Maybe; +using mozilla::Move; +using mozilla::Nothing; +using mozilla::Some; +using mozilla::Swap; +using mozilla::ToMaybe; +using mozilla::UniquePtr; + +#if MOZ_IS_MSVC + template<typename T> struct Identity { typedef T type; }; +# define DECLTYPE(EXPR) Identity<decltype(EXPR)>::type +#else +# define DECLTYPE(EXPR) decltype(EXPR) +#endif + +#define RUN_TEST(t) \ + do { \ + bool cond = (t()); \ + if (!cond) \ + return 1; \ + cond = AllDestructorsWereCalled(); \ + MOZ_ASSERT(cond, "Failed to destroy all objects during test: " #t); \ + if (!cond) \ + return 1; \ + } while (false) + +enum Status +{ + eWasDefaultConstructed, + eWasConstructed, + eWasCopyConstructed, + eWasMoveConstructed, + eWasCopyAssigned, + eWasMoveAssigned, + eWasMovedFrom +}; + +static size_t sUndestroyedObjects = 0; + +static bool AllDestructorsWereCalled() +{ + return sUndestroyedObjects == 0; +} + +struct BasicValue +{ + BasicValue() + : mStatus(eWasDefaultConstructed) + , mTag(0) + { + ++sUndestroyedObjects; + } + + explicit BasicValue(int aTag) + : mStatus(eWasConstructed) + , mTag(aTag) + { + ++sUndestroyedObjects; + } + + BasicValue(const BasicValue& aOther) + : mStatus(eWasCopyConstructed) + , mTag(aOther.mTag) + { + ++sUndestroyedObjects; + } + + BasicValue(BasicValue&& aOther) + : mStatus(eWasMoveConstructed) + , mTag(aOther.mTag) + { + ++sUndestroyedObjects; + aOther.mStatus = eWasMovedFrom; + aOther.mTag = 0; + } + + ~BasicValue() { --sUndestroyedObjects; } + + BasicValue& operator=(const BasicValue& aOther) + { + mStatus = eWasCopyAssigned; + mTag = aOther.mTag; + return *this; + } + + BasicValue& operator=(BasicValue&& aOther) + { + mStatus = eWasMoveAssigned; + mTag = aOther.mTag; + aOther.mStatus = eWasMovedFrom; + aOther.mTag = 0; + return *this; + } + + bool operator==(const BasicValue& aOther) const + { + return mTag == aOther.mTag; + } + + bool operator<(const BasicValue& aOther) const + { + return mTag < aOther.mTag; + } + + Status GetStatus() const { return mStatus; } + void SetTag(int aValue) { mTag = aValue; } + int GetTag() const { return mTag; } + +private: + Status mStatus; + int mTag; +}; + +struct UncopyableValue +{ + UncopyableValue() + : mStatus(eWasDefaultConstructed) + { + ++sUndestroyedObjects; + } + + UncopyableValue(UncopyableValue&& aOther) + : mStatus(eWasMoveConstructed) + { + ++sUndestroyedObjects; + aOther.mStatus = eWasMovedFrom; + } + + ~UncopyableValue() { --sUndestroyedObjects; } + + UncopyableValue& operator=(UncopyableValue&& aOther) + { + mStatus = eWasMoveAssigned; + aOther.mStatus = eWasMovedFrom; + return *this; + } + + Status GetStatus() { return mStatus; } + +private: + UncopyableValue(const UncopyableValue& aOther) = delete; + UncopyableValue& operator=(const UncopyableValue& aOther) = delete; + + Status mStatus; +}; + +struct UnmovableValue +{ + UnmovableValue() + : mStatus(eWasDefaultConstructed) + { + ++sUndestroyedObjects; + } + + UnmovableValue(const UnmovableValue& aOther) + : mStatus(eWasCopyConstructed) + { + ++sUndestroyedObjects; + } + + ~UnmovableValue() { --sUndestroyedObjects; } + + UnmovableValue& operator=(const UnmovableValue& aOther) + { + mStatus = eWasCopyAssigned; + return *this; + } + + Status GetStatus() { return mStatus; } + +private: + UnmovableValue(UnmovableValue&& aOther) = delete; + UnmovableValue& operator=(UnmovableValue&& aOther) = delete; + + Status mStatus; +}; + +struct UncopyableUnmovableValue +{ + UncopyableUnmovableValue() + : mStatus(eWasDefaultConstructed) + { + ++sUndestroyedObjects; + } + + explicit UncopyableUnmovableValue(int) + : mStatus(eWasConstructed) + { + ++sUndestroyedObjects; + } + + ~UncopyableUnmovableValue() { --sUndestroyedObjects; } + + Status GetStatus() { return mStatus; } + +private: + UncopyableUnmovableValue(const UncopyableUnmovableValue& aOther) = delete; + UncopyableUnmovableValue& operator=(const UncopyableUnmovableValue& aOther) = delete; + UncopyableUnmovableValue(UncopyableUnmovableValue&& aOther) = delete; + UncopyableUnmovableValue& operator=(UncopyableUnmovableValue&& aOther) = delete; + + Status mStatus; +}; + +static bool +TestBasicFeatures() +{ + // Check that a Maybe<T> is initialized to Nothing. + Maybe<BasicValue> mayValue; + static_assert(IsSame<BasicValue, DECLTYPE(mayValue)::ValueType>::value, + "Should have BasicValue ValueType"); + MOZ_RELEASE_ASSERT(!mayValue); + MOZ_RELEASE_ASSERT(!mayValue.isSome()); + MOZ_RELEASE_ASSERT(mayValue.isNothing()); + + // Check that emplace() default constructs and the accessors work. + mayValue.emplace(); + MOZ_RELEASE_ASSERT(mayValue); + MOZ_RELEASE_ASSERT(mayValue.isSome()); + MOZ_RELEASE_ASSERT(!mayValue.isNothing()); + MOZ_RELEASE_ASSERT(*mayValue == BasicValue()); + MOZ_RELEASE_ASSERT(mayValue.value() == BasicValue()); + static_assert(IsSame<BasicValue, DECLTYPE(mayValue.value())>::value, + "value() should return a BasicValue"); + MOZ_RELEASE_ASSERT(mayValue.ref() == BasicValue()); + static_assert(IsSame<BasicValue&, DECLTYPE(mayValue.ref())>::value, + "ref() should return a BasicValue&"); + MOZ_RELEASE_ASSERT(mayValue.ptr() != nullptr); + static_assert(IsSame<BasicValue*, DECLTYPE(mayValue.ptr())>::value, + "ptr() should return a BasicValue*"); + MOZ_RELEASE_ASSERT(mayValue->GetStatus() == eWasDefaultConstructed); + + // Check that reset() works. + mayValue.reset(); + MOZ_RELEASE_ASSERT(!mayValue); + MOZ_RELEASE_ASSERT(!mayValue.isSome()); + MOZ_RELEASE_ASSERT(mayValue.isNothing()); + + // Check that emplace(T1) calls the correct constructor. + mayValue.emplace(1); + MOZ_RELEASE_ASSERT(mayValue); + MOZ_RELEASE_ASSERT(mayValue->GetStatus() == eWasConstructed); + MOZ_RELEASE_ASSERT(mayValue->GetTag() == 1); + mayValue.reset(); + MOZ_RELEASE_ASSERT(!mayValue); + + // Check that Some() and Nothing() work. + mayValue = Some(BasicValue(2)); + MOZ_RELEASE_ASSERT(mayValue); + MOZ_RELEASE_ASSERT(mayValue->GetStatus() == eWasMoveConstructed); + MOZ_RELEASE_ASSERT(mayValue->GetTag() == 2); + mayValue = Nothing(); + MOZ_RELEASE_ASSERT(!mayValue); + + // Check that the accessors work through a const ref. + mayValue.emplace(); + const Maybe<BasicValue>& mayValueCRef = mayValue; + MOZ_RELEASE_ASSERT(mayValueCRef); + MOZ_RELEASE_ASSERT(mayValueCRef.isSome()); + MOZ_RELEASE_ASSERT(!mayValueCRef.isNothing()); + MOZ_RELEASE_ASSERT(*mayValueCRef == BasicValue()); + MOZ_RELEASE_ASSERT(mayValueCRef.value() == BasicValue()); + static_assert(IsSame<BasicValue, DECLTYPE(mayValueCRef.value())>::value, + "value() should return a BasicValue"); + MOZ_RELEASE_ASSERT(mayValueCRef.ref() == BasicValue()); + static_assert(IsSame<const BasicValue&, + DECLTYPE(mayValueCRef.ref())>::value, + "ref() should return a const BasicValue&"); + MOZ_RELEASE_ASSERT(mayValueCRef.ptr() != nullptr); + static_assert(IsSame<const BasicValue*, + DECLTYPE(mayValueCRef.ptr())>::value, + "ptr() should return a const BasicValue*"); + MOZ_RELEASE_ASSERT(mayValueCRef->GetStatus() == eWasDefaultConstructed); + mayValue.reset(); + + return true; +} + +static bool +TestCopyAndMove() +{ + // Check that we get moves when possible for types that can support both moves + // and copies. + Maybe<BasicValue> mayBasicValue = Some(BasicValue(1)); + MOZ_RELEASE_ASSERT(mayBasicValue->GetStatus() == eWasMoveConstructed); + MOZ_RELEASE_ASSERT(mayBasicValue->GetTag() == 1); + mayBasicValue = Some(BasicValue(2)); + MOZ_RELEASE_ASSERT(mayBasicValue->GetStatus() == eWasMoveAssigned); + MOZ_RELEASE_ASSERT(mayBasicValue->GetTag() == 2); + mayBasicValue.reset(); + mayBasicValue.emplace(BasicValue(3)); + MOZ_RELEASE_ASSERT(mayBasicValue->GetStatus() == eWasMoveConstructed); + MOZ_RELEASE_ASSERT(mayBasicValue->GetTag() == 3); + + // Check that we get copies when moves aren't possible. + Maybe<BasicValue> mayBasicValue2 = Some(*mayBasicValue); + MOZ_RELEASE_ASSERT(mayBasicValue2->GetStatus() == eWasCopyConstructed); + MOZ_RELEASE_ASSERT(mayBasicValue2->GetTag() == 3); + mayBasicValue->SetTag(4); + mayBasicValue2 = mayBasicValue; + // This test should work again when we fix bug 1052940. + //MOZ_RELEASE_ASSERT(mayBasicValue2->GetStatus() == eWasCopyAssigned); + MOZ_RELEASE_ASSERT(mayBasicValue2->GetTag() == 4); + mayBasicValue->SetTag(5); + mayBasicValue2.reset(); + mayBasicValue2.emplace(*mayBasicValue); + MOZ_RELEASE_ASSERT(mayBasicValue2->GetStatus() == eWasCopyConstructed); + MOZ_RELEASE_ASSERT(mayBasicValue2->GetTag() == 5); + + // Check that Move() works. (Another sanity check for move support.) + Maybe<BasicValue> mayBasicValue3 = Some(Move(*mayBasicValue)); + MOZ_RELEASE_ASSERT(mayBasicValue3->GetStatus() == eWasMoveConstructed); + MOZ_RELEASE_ASSERT(mayBasicValue3->GetTag() == 5); + MOZ_RELEASE_ASSERT(mayBasicValue->GetStatus() == eWasMovedFrom); + mayBasicValue2->SetTag(6); + mayBasicValue3 = Some(Move(*mayBasicValue2)); + MOZ_RELEASE_ASSERT(mayBasicValue3->GetStatus() == eWasMoveAssigned); + MOZ_RELEASE_ASSERT(mayBasicValue3->GetTag() == 6); + MOZ_RELEASE_ASSERT(mayBasicValue2->GetStatus() == eWasMovedFrom); + Maybe<BasicValue> mayBasicValue4; + mayBasicValue4.emplace(Move(*mayBasicValue3)); + MOZ_RELEASE_ASSERT(mayBasicValue4->GetStatus() == eWasMoveConstructed); + MOZ_RELEASE_ASSERT(mayBasicValue4->GetTag() == 6); + MOZ_RELEASE_ASSERT(mayBasicValue3->GetStatus() == eWasMovedFrom); + + // Check that we always get copies for types that don't support moves. + // XXX(seth): These tests fail but probably shouldn't. For now we'll just + // consider using Maybe with types that allow copies but have deleted or + // private move constructors, or which do not support copy assignment, to + // be supported only to the extent that we need for existing code to work. + // These tests should work again when we fix bug 1052940. + /* + Maybe<UnmovableValue> mayUnmovableValue = Some(UnmovableValue()); + MOZ_RELEASE_ASSERT(mayUnmovableValue->GetStatus() == eWasCopyConstructed); + mayUnmovableValue = Some(UnmovableValue()); + MOZ_RELEASE_ASSERT(mayUnmovableValue->GetStatus() == eWasCopyAssigned); + mayUnmovableValue.reset(); + mayUnmovableValue.emplace(UnmovableValue()); + MOZ_RELEASE_ASSERT(mayUnmovableValue->GetStatus() == eWasCopyConstructed); + */ + + // Check that types that only support moves, but not copies, work. + Maybe<UncopyableValue> mayUncopyableValue = Some(UncopyableValue()); + MOZ_RELEASE_ASSERT(mayUncopyableValue->GetStatus() == eWasMoveConstructed); + mayUncopyableValue = Some(UncopyableValue()); + MOZ_RELEASE_ASSERT(mayUncopyableValue->GetStatus() == eWasMoveAssigned); + mayUncopyableValue.reset(); + mayUncopyableValue.emplace(UncopyableValue()); + MOZ_RELEASE_ASSERT(mayUncopyableValue->GetStatus() == eWasMoveConstructed); + + // Check that types that support neither moves or copies work. + Maybe<UncopyableUnmovableValue> mayUncopyableUnmovableValue; + mayUncopyableUnmovableValue.emplace(); + MOZ_RELEASE_ASSERT(mayUncopyableUnmovableValue->GetStatus() == eWasDefaultConstructed); + mayUncopyableUnmovableValue.reset(); + mayUncopyableUnmovableValue.emplace(0); + MOZ_RELEASE_ASSERT(mayUncopyableUnmovableValue->GetStatus() == eWasConstructed); + + return true; +} + +static BasicValue* sStaticBasicValue = nullptr; + +static BasicValue +MakeBasicValue() +{ + return BasicValue(9); +} + +static BasicValue& +MakeBasicValueRef() +{ + return *sStaticBasicValue; +} + +static BasicValue* +MakeBasicValuePtr() +{ + return sStaticBasicValue; +} + +static bool +TestFunctionalAccessors() +{ + BasicValue value(9); + sStaticBasicValue = new BasicValue(9); + + // Check that the 'some' case of functional accessors works. + Maybe<BasicValue> someValue = Some(BasicValue(3)); + MOZ_RELEASE_ASSERT(someValue.valueOr(value) == BasicValue(3)); + static_assert(IsSame<BasicValue, + DECLTYPE(someValue.valueOr(value))>::value, + "valueOr should return a BasicValue"); + MOZ_RELEASE_ASSERT(someValue.valueOrFrom(&MakeBasicValue) == BasicValue(3)); + static_assert(IsSame<BasicValue, + DECLTYPE(someValue.valueOrFrom(&MakeBasicValue))>::value, + "valueOrFrom should return a BasicValue"); + MOZ_RELEASE_ASSERT(someValue.ptrOr(&value) != &value); + static_assert(IsSame<BasicValue*, + DECLTYPE(someValue.ptrOr(&value))>::value, + "ptrOr should return a BasicValue*"); + MOZ_RELEASE_ASSERT(*someValue.ptrOrFrom(&MakeBasicValuePtr) == BasicValue(3)); + static_assert(IsSame<BasicValue*, + DECLTYPE(someValue.ptrOrFrom(&MakeBasicValuePtr))>::value, + "ptrOrFrom should return a BasicValue*"); + MOZ_RELEASE_ASSERT(someValue.refOr(value) == BasicValue(3)); + static_assert(IsSame<BasicValue&, + DECLTYPE(someValue.refOr(value))>::value, + "refOr should return a BasicValue&"); + MOZ_RELEASE_ASSERT(someValue.refOrFrom(&MakeBasicValueRef) == BasicValue(3)); + static_assert(IsSame<BasicValue&, + DECLTYPE(someValue.refOrFrom(&MakeBasicValueRef))>::value, + "refOrFrom should return a BasicValue&"); + + // Check that the 'some' case works through a const reference. + const Maybe<BasicValue>& someValueCRef = someValue; + MOZ_RELEASE_ASSERT(someValueCRef.valueOr(value) == BasicValue(3)); + static_assert(IsSame<BasicValue, + DECLTYPE(someValueCRef.valueOr(value))>::value, + "valueOr should return a BasicValue"); + MOZ_RELEASE_ASSERT(someValueCRef.valueOrFrom(&MakeBasicValue) == BasicValue(3)); + static_assert(IsSame<BasicValue, + DECLTYPE(someValueCRef.valueOrFrom(&MakeBasicValue))>::value, + "valueOrFrom should return a BasicValue"); + MOZ_RELEASE_ASSERT(someValueCRef.ptrOr(&value) != &value); + static_assert(IsSame<const BasicValue*, + DECLTYPE(someValueCRef.ptrOr(&value))>::value, + "ptrOr should return a const BasicValue*"); + MOZ_RELEASE_ASSERT(*someValueCRef.ptrOrFrom(&MakeBasicValuePtr) == BasicValue(3)); + static_assert(IsSame<const BasicValue*, + DECLTYPE(someValueCRef.ptrOrFrom(&MakeBasicValuePtr))>::value, + "ptrOrFrom should return a const BasicValue*"); + MOZ_RELEASE_ASSERT(someValueCRef.refOr(value) == BasicValue(3)); + static_assert(IsSame<const BasicValue&, + DECLTYPE(someValueCRef.refOr(value))>::value, + "refOr should return a const BasicValue&"); + MOZ_RELEASE_ASSERT(someValueCRef.refOrFrom(&MakeBasicValueRef) == BasicValue(3)); + static_assert(IsSame<const BasicValue&, + DECLTYPE(someValueCRef.refOrFrom(&MakeBasicValueRef))>::value, + "refOrFrom should return a const BasicValue&"); + + // Check that the 'none' case of functional accessors works. + Maybe<BasicValue> noneValue; + MOZ_RELEASE_ASSERT(noneValue.valueOr(value) == BasicValue(9)); + static_assert(IsSame<BasicValue, + DECLTYPE(noneValue.valueOr(value))>::value, + "valueOr should return a BasicValue"); + MOZ_RELEASE_ASSERT(noneValue.valueOrFrom(&MakeBasicValue) == BasicValue(9)); + static_assert(IsSame<BasicValue, + DECLTYPE(noneValue.valueOrFrom(&MakeBasicValue))>::value, + "valueOrFrom should return a BasicValue"); + MOZ_RELEASE_ASSERT(noneValue.ptrOr(&value) == &value); + static_assert(IsSame<BasicValue*, + DECLTYPE(noneValue.ptrOr(&value))>::value, + "ptrOr should return a BasicValue*"); + MOZ_RELEASE_ASSERT(*noneValue.ptrOrFrom(&MakeBasicValuePtr) == BasicValue(9)); + static_assert(IsSame<BasicValue*, + DECLTYPE(noneValue.ptrOrFrom(&MakeBasicValuePtr))>::value, + "ptrOrFrom should return a BasicValue*"); + MOZ_RELEASE_ASSERT(noneValue.refOr(value) == BasicValue(9)); + static_assert(IsSame<BasicValue&, + DECLTYPE(noneValue.refOr(value))>::value, + "refOr should return a BasicValue&"); + MOZ_RELEASE_ASSERT(noneValue.refOrFrom(&MakeBasicValueRef) == BasicValue(9)); + static_assert(IsSame<BasicValue&, + DECLTYPE(noneValue.refOrFrom(&MakeBasicValueRef))>::value, + "refOrFrom should return a BasicValue&"); + + // Check that the 'none' case works through a const reference. + const Maybe<BasicValue>& noneValueCRef = noneValue; + MOZ_RELEASE_ASSERT(noneValueCRef.valueOr(value) == BasicValue(9)); + static_assert(IsSame<BasicValue, + DECLTYPE(noneValueCRef.valueOr(value))>::value, + "valueOr should return a BasicValue"); + MOZ_RELEASE_ASSERT(noneValueCRef.valueOrFrom(&MakeBasicValue) == BasicValue(9)); + static_assert(IsSame<BasicValue, + DECLTYPE(noneValueCRef.valueOrFrom(&MakeBasicValue))>::value, + "valueOrFrom should return a BasicValue"); + MOZ_RELEASE_ASSERT(noneValueCRef.ptrOr(&value) == &value); + static_assert(IsSame<const BasicValue*, + DECLTYPE(noneValueCRef.ptrOr(&value))>::value, + "ptrOr should return a const BasicValue*"); + MOZ_RELEASE_ASSERT(*noneValueCRef.ptrOrFrom(&MakeBasicValuePtr) == BasicValue(9)); + static_assert(IsSame<const BasicValue*, + DECLTYPE(noneValueCRef.ptrOrFrom(&MakeBasicValuePtr))>::value, + "ptrOrFrom should return a const BasicValue*"); + MOZ_RELEASE_ASSERT(noneValueCRef.refOr(value) == BasicValue(9)); + static_assert(IsSame<const BasicValue&, + DECLTYPE(noneValueCRef.refOr(value))>::value, + "refOr should return a const BasicValue&"); + MOZ_RELEASE_ASSERT(noneValueCRef.refOrFrom(&MakeBasicValueRef) == BasicValue(9)); + static_assert(IsSame<const BasicValue&, + DECLTYPE(noneValueCRef.refOrFrom(&MakeBasicValueRef))>::value, + "refOrFrom should return a const BasicValue&"); + + // Clean up so the undestroyed objects count stays accurate. + delete sStaticBasicValue; + sStaticBasicValue = nullptr; + + return true; +} + +static bool gFunctionWasApplied = false; + +static void +IncrementTag(BasicValue& aValue) +{ + gFunctionWasApplied = true; + aValue.SetTag(aValue.GetTag() + 1); +} + +static void +AccessValue(const BasicValue&) +{ + gFunctionWasApplied = true; +} + +struct IncrementTagFunctor +{ + IncrementTagFunctor() : mBy(1) { } + + void operator()(BasicValue& aValue) + { + aValue.SetTag(aValue.GetTag() + mBy.GetTag()); + } + + BasicValue mBy; +}; + +static bool +TestApply() +{ + // Check that apply handles the 'Nothing' case. + gFunctionWasApplied = false; + Maybe<BasicValue> mayValue; + mayValue.apply(&IncrementTag); + mayValue.apply(&AccessValue); + MOZ_RELEASE_ASSERT(!gFunctionWasApplied); + + // Check that apply handles the 'Some' case. + mayValue = Some(BasicValue(1)); + mayValue.apply(&IncrementTag); + MOZ_RELEASE_ASSERT(gFunctionWasApplied); + MOZ_RELEASE_ASSERT(mayValue->GetTag() == 2); + gFunctionWasApplied = false; + mayValue.apply(&AccessValue); + MOZ_RELEASE_ASSERT(gFunctionWasApplied); + + // Check that apply works with a const reference. + const Maybe<BasicValue>& mayValueCRef = mayValue; + gFunctionWasApplied = false; + mayValueCRef.apply(&AccessValue); + MOZ_RELEASE_ASSERT(gFunctionWasApplied); + + // Check that apply works with functors. + IncrementTagFunctor tagIncrementer; + MOZ_RELEASE_ASSERT(tagIncrementer.mBy.GetStatus() == eWasConstructed); + mayValue = Some(BasicValue(1)); + mayValue.apply(tagIncrementer); + MOZ_RELEASE_ASSERT(mayValue->GetTag() == 2); + MOZ_RELEASE_ASSERT(tagIncrementer.mBy.GetStatus() == eWasConstructed); + + // Check that apply works with lambda expressions. + int32_t two = 2; + gFunctionWasApplied = false; + mayValue = Some(BasicValue(2)); + mayValue.apply([&](BasicValue& aVal) { aVal.SetTag(aVal.GetTag() * two); }); + MOZ_RELEASE_ASSERT(mayValue->GetTag() == 4); + mayValue.apply([=](BasicValue& aVal) { aVal.SetTag(aVal.GetTag() * two); }); + MOZ_RELEASE_ASSERT(mayValue->GetTag() == 8); + mayValueCRef.apply([&](const BasicValue& aVal) { gFunctionWasApplied = true; }); + MOZ_RELEASE_ASSERT(gFunctionWasApplied == true); + + return true; +} + +static int +TimesTwo(const BasicValue& aValue) +{ + return aValue.GetTag() * 2; +} + +static int +TimesTwoAndResetOriginal(BasicValue& aValue) +{ + int tag = aValue.GetTag(); + aValue.SetTag(1); + return tag * 2; +} + +struct MultiplyTagFunctor +{ + MultiplyTagFunctor() : mBy(2) { } + + int operator()(BasicValue& aValue) + { + return aValue.GetTag() * mBy.GetTag(); + } + + BasicValue mBy; +}; + +static bool +TestMap() +{ + // Check that map handles the 'Nothing' case. + Maybe<BasicValue> mayValue; + MOZ_RELEASE_ASSERT(mayValue.map(&TimesTwo) == Nothing()); + static_assert(IsSame<Maybe<int>, + DECLTYPE(mayValue.map(&TimesTwo))>::value, + "map(TimesTwo) should return a Maybe<int>"); + MOZ_RELEASE_ASSERT(mayValue.map(&TimesTwoAndResetOriginal) == Nothing()); + + // Check that map handles the 'Some' case. + mayValue = Some(BasicValue(2)); + MOZ_RELEASE_ASSERT(mayValue.map(&TimesTwo) == Some(4)); + MOZ_RELEASE_ASSERT(mayValue.map(&TimesTwoAndResetOriginal) == Some(4)); + MOZ_RELEASE_ASSERT(mayValue->GetTag() == 1); + mayValue = Some(BasicValue(2)); + + // Check that map works with a const reference. + mayValue->SetTag(2); + const Maybe<BasicValue>& mayValueCRef = mayValue; + MOZ_RELEASE_ASSERT(mayValueCRef.map(&TimesTwo) == Some(4)); + static_assert(IsSame<Maybe<int>, + DECLTYPE(mayValueCRef.map(&TimesTwo))>::value, + "map(TimesTwo) should return a Maybe<int>"); + + // Check that map works with functors. + MultiplyTagFunctor tagMultiplier; + MOZ_RELEASE_ASSERT(tagMultiplier.mBy.GetStatus() == eWasConstructed); + MOZ_RELEASE_ASSERT(mayValue.map(tagMultiplier) == Some(4)); + MOZ_RELEASE_ASSERT(tagMultiplier.mBy.GetStatus() == eWasConstructed); + + // Check that map works with lambda expressions. + int two = 2; + mayValue = Some(BasicValue(2)); + Maybe<int> mappedValue = + mayValue.map([&](const BasicValue& aVal) { + return aVal.GetTag() * two; + }); + MOZ_RELEASE_ASSERT(mappedValue == Some(4)); + mappedValue = + mayValue.map([=](const BasicValue& aVal) { + return aVal.GetTag() * two; + }); + MOZ_RELEASE_ASSERT(mappedValue == Some(4)); + mappedValue = + mayValueCRef.map([&](const BasicValue& aVal) { + return aVal.GetTag() * two; + }); + MOZ_RELEASE_ASSERT(mappedValue == Some(4)); + + return true; +} + +static bool +TestToMaybe() +{ + BasicValue value(1); + BasicValue* nullPointer = nullptr; + + // Check that a non-null pointer translates into a Some value. + Maybe<BasicValue> mayValue = ToMaybe(&value); + static_assert(IsSame<Maybe<BasicValue>, DECLTYPE(ToMaybe(&value))>::value, + "ToMaybe should return a Maybe<BasicValue>"); + MOZ_RELEASE_ASSERT(mayValue.isSome()); + MOZ_RELEASE_ASSERT(mayValue->GetTag() == 1); + MOZ_RELEASE_ASSERT(mayValue->GetStatus() == eWasCopyConstructed); + MOZ_RELEASE_ASSERT(value.GetStatus() != eWasMovedFrom); + + // Check that a null pointer translates into a Nothing value. + mayValue = ToMaybe(nullPointer); + static_assert(IsSame<Maybe<BasicValue>, DECLTYPE(ToMaybe(nullPointer))>::value, + "ToMaybe should return a Maybe<BasicValue>"); + MOZ_RELEASE_ASSERT(mayValue.isNothing()); + + return true; +} + +static bool +TestComparisonOperators() +{ + Maybe<BasicValue> nothingValue = Nothing(); + Maybe<BasicValue> anotherNothingValue = Nothing(); + Maybe<BasicValue> oneValue = Some(BasicValue(1)); + Maybe<BasicValue> anotherOneValue = Some(BasicValue(1)); + Maybe<BasicValue> twoValue = Some(BasicValue(2)); + + // Check equality. + MOZ_RELEASE_ASSERT(nothingValue == anotherNothingValue); + MOZ_RELEASE_ASSERT(oneValue == anotherOneValue); + + // Check inequality. + MOZ_RELEASE_ASSERT(nothingValue != oneValue); + MOZ_RELEASE_ASSERT(oneValue != nothingValue); + MOZ_RELEASE_ASSERT(oneValue != twoValue); + + // Check '<'. + MOZ_RELEASE_ASSERT(nothingValue < oneValue); + MOZ_RELEASE_ASSERT(oneValue < twoValue); + + // Check '<='. + MOZ_RELEASE_ASSERT(nothingValue <= anotherNothingValue); + MOZ_RELEASE_ASSERT(nothingValue <= oneValue); + MOZ_RELEASE_ASSERT(oneValue <= oneValue); + MOZ_RELEASE_ASSERT(oneValue <= twoValue); + + // Check '>'. + MOZ_RELEASE_ASSERT(oneValue > nothingValue); + MOZ_RELEASE_ASSERT(twoValue > oneValue); + + // Check '>='. + MOZ_RELEASE_ASSERT(nothingValue >= anotherNothingValue); + MOZ_RELEASE_ASSERT(oneValue >= nothingValue); + MOZ_RELEASE_ASSERT(oneValue >= oneValue); + MOZ_RELEASE_ASSERT(twoValue >= oneValue); + + return true; +} + +// Check that Maybe<> can wrap a superclass that happens to also be a concrete +// class (i.e. that the compiler doesn't warn when we invoke the superclass's +// destructor explicitly in |reset()|. +class MySuperClass { + virtual void VirtualMethod() { /* do nothing */ } +}; + +class MyDerivedClass : public MySuperClass { + void VirtualMethod() override { /* do nothing */ } +}; + +static bool +TestVirtualFunction() { + Maybe<MySuperClass> super; + super.emplace(); + super.reset(); + + Maybe<MyDerivedClass> derived; + derived.emplace(); + derived.reset(); + + // If this compiles successfully, we've passed. + return true; +} + +static Maybe<int*> +ReturnSomeNullptr() +{ + return Some(nullptr); +} + +struct D +{ + explicit D(Maybe<int*>) {} +}; + +static bool +TestSomeNullptrConversion() +{ + Maybe<int*> m1 = Some(nullptr); + MOZ_RELEASE_ASSERT(m1.isSome()); + MOZ_RELEASE_ASSERT(m1); + MOZ_RELEASE_ASSERT(!*m1); + + auto m2 = ReturnSomeNullptr(); + MOZ_RELEASE_ASSERT(m2.isSome()); + MOZ_RELEASE_ASSERT(m2); + MOZ_RELEASE_ASSERT(!*m2); + + Maybe<decltype(nullptr)> m3 = Some(nullptr); + MOZ_RELEASE_ASSERT(m3.isSome()); + MOZ_RELEASE_ASSERT(m3); + MOZ_RELEASE_ASSERT(*m3 == nullptr); + + D d(Some(nullptr)); + + return true; +} + +struct Base {}; +struct Derived : Base {}; + +static Maybe<Base*> +ReturnDerivedPointer() +{ + Derived* d = nullptr; + return Some(d); +} + +struct ExplicitConstructorBasePointer +{ + explicit ExplicitConstructorBasePointer(Maybe<Base*>) {} +}; + +static bool +TestSomePointerConversion() +{ + Base base; + Derived derived; + + Maybe<Base*> m1 = Some(&derived); + MOZ_RELEASE_ASSERT(m1.isSome()); + MOZ_RELEASE_ASSERT(m1); + MOZ_RELEASE_ASSERT(*m1 == &derived); + + auto m2 = ReturnDerivedPointer(); + MOZ_RELEASE_ASSERT(m2.isSome()); + MOZ_RELEASE_ASSERT(m2); + MOZ_RELEASE_ASSERT(*m2 == nullptr); + + Maybe<Base*> m3 = Some(&base); + MOZ_RELEASE_ASSERT(m3.isSome()); + MOZ_RELEASE_ASSERT(m3); + MOZ_RELEASE_ASSERT(*m3 == &base); + + auto s1 = Some(&derived); + Maybe<Base*> c1(s1); + MOZ_RELEASE_ASSERT(c1.isSome()); + MOZ_RELEASE_ASSERT(c1); + MOZ_RELEASE_ASSERT(*c1 == &derived); + + ExplicitConstructorBasePointer ecbp(Some(&derived)); + + return true; +} + +int +main() +{ + RUN_TEST(TestBasicFeatures); + RUN_TEST(TestCopyAndMove); + RUN_TEST(TestFunctionalAccessors); + RUN_TEST(TestApply); + RUN_TEST(TestMap); + RUN_TEST(TestToMaybe); + RUN_TEST(TestComparisonOperators); + RUN_TEST(TestVirtualFunction); + RUN_TEST(TestSomeNullptrConversion); + RUN_TEST(TestSomePointerConversion); + + return 0; +} diff --git a/mfbt/tests/TestNotNull.cpp b/mfbt/tests/TestNotNull.cpp new file mode 100644 index 000000000..4642dd93e --- /dev/null +++ b/mfbt/tests/TestNotNull.cpp @@ -0,0 +1,314 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/NotNull.h" +#include "mozilla/RefPtr.h" +#include "mozilla/UniquePtr.h" +#include "mozilla/Unused.h" + +using mozilla::WrapNotNull; +using mozilla::MakeUnique; +using mozilla::NotNull; +using mozilla::UniquePtr; + +#define CHECK MOZ_RELEASE_ASSERT + +class Blah +{ +public: + Blah() : mX(0) {} + void blah() {}; + int mX; +}; + +// A simple smart pointer that implicity converts to and from T*. +template <typename T> +class MyPtr +{ + T* mRawPtr; + +public: + MyPtr() : mRawPtr(nullptr) {} + MOZ_IMPLICIT MyPtr(T* aRawPtr) : mRawPtr(aRawPtr) {} + + T* get() const { return mRawPtr; } + operator T*() const { return get(); } + + T* operator->() const { return get(); } +}; + +// A simple class that works with RefPtr. It keeps track of the maximum +// refcount value for testing purposes. +class MyRefType +{ + int mExpectedMaxRefCnt; + int mMaxRefCnt; + int mRefCnt; +public: + explicit MyRefType(int aExpectedMaxRefCnt) + : mExpectedMaxRefCnt(aExpectedMaxRefCnt) + , mMaxRefCnt(0) + , mRefCnt(0) + {} + + ~MyRefType() { + CHECK(mMaxRefCnt == mExpectedMaxRefCnt); + } + + uint32_t AddRef() { + mRefCnt++; + if (mRefCnt > mMaxRefCnt) { + mMaxRefCnt = mRefCnt; + } + return mRefCnt; + } + + uint32_t Release() { + CHECK(mRefCnt > 0); + mRefCnt--; + if (mRefCnt == 0) { + delete this; + return 0; + } + return mRefCnt; + } +}; + +void f_i(int* aPtr) {} +void f_my(MyPtr<int> aPtr) {} + +void f_nni(NotNull<int*> aPtr) {} +void f_nnmy(NotNull<MyPtr<int>> aPtr) {} + +void +TestNotNullWithMyPtr() +{ + int i4 = 4; + int i5 = 5; + + MyPtr<int> my4 = &i4; + MyPtr<int> my5 = &i5; + + NotNull<int*> nni4 = WrapNotNull(&i4); + NotNull<int*> nni5 = WrapNotNull(&i5); + NotNull<MyPtr<int>> nnmy4 = WrapNotNull(my4); + + //WrapNotNull(nullptr); // no wrapping from nullptr + //WrapNotNull(0); // no wrapping from zero + + // NotNull<int*> construction combinations + //NotNull<int*> nni4a; // no default + //NotNull<int*> nni4a(nullptr); // no nullptr + //NotNull<int*> nni4a(0); // no zero + //NotNull<int*> nni4a(&i4); // no int* + //NotNull<int*> nni4a(my4); // no MyPtr<int> + NotNull<int*> nni4b(WrapNotNull(&i4)); // WrapNotNull(int*) + NotNull<int*> nni4c(WrapNotNull(my4)); // WrapNotNull(MyPtr<int>) + NotNull<int*> nni4d(nni4); // NotNull<int*> + NotNull<int*> nni4e(nnmy4); // NotNull<MyPtr<int>> + CHECK(*nni4b == 4); + CHECK(*nni4c == 4); + CHECK(*nni4d == 4); + CHECK(*nni4e == 4); + + // NotNull<MyPtr<int>> construction combinations + //NotNull<MyPtr<int>> nnmy4a; // no default + //NotNull<MyPtr<int>> nnmy4a(nullptr); // no nullptr + //NotNull<MyPtr<int>> nnmy4a(0); // no zero + //NotNull<MyPtr<int>> nnmy4a(&i4); // no int* + //NotNull<MyPtr<int>> nnmy4a(my4); // no MyPtr<int> + NotNull<MyPtr<int>> nnmy4b(WrapNotNull(&i4)); // WrapNotNull(int*) + NotNull<MyPtr<int>> nnmy4c(WrapNotNull(my4)); // WrapNotNull(MyPtr<int>) + NotNull<MyPtr<int>> nnmy4d(nni4); // NotNull<int*> + NotNull<MyPtr<int>> nnmy4e(nnmy4); // NotNull<MyPtr<int>> + CHECK(*nnmy4b == 4); + CHECK(*nnmy4c == 4); + CHECK(*nnmy4d == 4); + CHECK(*nnmy4e == 4); + + // NotNull<int*> assignment combinations + //nni4b = nullptr; // no nullptr + //nni4b = 0; // no zero + //nni4a = &i4; // no int* + //nni4a = my4; // no MyPtr<int> + nni4b = WrapNotNull(&i4); // WrapNotNull(int*) + nni4c = WrapNotNull(my4); // WrapNotNull(MyPtr<int>) + nni4d = nni4; // NotNull<int*> + nni4e = nnmy4; // NotNull<MyPtr<int>> + CHECK(*nni4b == 4); + CHECK(*nni4c == 4); + CHECK(*nni4d == 4); + CHECK(*nni4e == 4); + + // NotNull<MyPtr<int>> assignment combinations + //nnmy4a = nullptr; // no nullptr + //nnmy4a = 0; // no zero + //nnmy4a = &i4; // no int* + //nnmy4a = my4; // no MyPtr<int> + nnmy4b = WrapNotNull(&i4); // WrapNotNull(int*) + nnmy4c = WrapNotNull(my4); // WrapNotNull(MyPtr<int>) + nnmy4d = nni4; // NotNull<int*> + nnmy4e = nnmy4; // NotNull<MyPtr<int>> + CHECK(*nnmy4b == 4); + CHECK(*nnmy4c == 4); + CHECK(*nnmy4d == 4); + CHECK(*nnmy4e == 4); + + NotNull<MyPtr<int>> nnmy5 = WrapNotNull(&i5); + CHECK(*nnmy5 == 5); + CHECK(nnmy5 == &i5); // NotNull<MyPtr<int>> == int* + CHECK(nnmy5 == my5); // NotNull<MyPtr<int>> == MyPtr<int> + CHECK(nnmy5 == nni5); // NotNull<MyPtr<int>> == NotNull<int*> + CHECK(nnmy5 == nnmy5); // NotNull<MyPtr<int>> == NotNull<MyPtr<int>> + CHECK(&i5 == nnmy5); // int* == NotNull<MyPtr<int>> + CHECK(my5 == nnmy5); // MyPtr<int> == NotNull<MyPtr<int>> + CHECK(nni5 == nnmy5); // NotNull<int*> == NotNull<MyPtr<int>> + CHECK(nnmy5 == nnmy5); // NotNull<MyPtr<int>> == NotNull<MyPtr<int>> + //CHECK(nni5 == nullptr); // no comparisons with nullptr + //CHECK(nullptr == nni5); // no comparisons with nullptr + //CHECK(nni5 == 0); // no comparisons with zero + //CHECK(0 == nni5); // no comparisons with zero + + CHECK(*nnmy5 == 5); + CHECK(nnmy5 != &i4); // NotNull<MyPtr<int>> != int* + CHECK(nnmy5 != my4); // NotNull<MyPtr<int>> != MyPtr<int> + CHECK(nnmy5 != nni4); // NotNull<MyPtr<int>> != NotNull<int*> + CHECK(nnmy5 != nnmy4); // NotNull<MyPtr<int>> != NotNull<MyPtr<int>> + CHECK(&i4 != nnmy5); // int* != NotNull<MyPtr<int>> + CHECK(my4 != nnmy5); // MyPtr<int> != NotNull<MyPtr<int>> + CHECK(nni4 != nnmy5); // NotNull<int*> != NotNull<MyPtr<int>> + CHECK(nnmy4 != nnmy5); // NotNull<MyPtr<int>> != NotNull<MyPtr<int>> + //CHECK(nni4 != nullptr); // no comparisons with nullptr + //CHECK(nullptr != nni4); // no comparisons with nullptr + //CHECK(nni4 != 0); // no comparisons with zero + //CHECK(0 != nni4); // no comparisons with zero + + // int* parameter + f_i(&i4); // identity int* --> int* + f_i(my4); // implicit MyPtr<int> --> int* + f_i(my4.get()); // explicit MyPtr<int> --> int* + f_i(nni4); // implicit NotNull<int*> --> int* + f_i(nni4.get()); // explicit NotNull<int*> --> int* + //f_i(nnmy4); // no implicit NotNull<MyPtr<int>> --> int* + f_i(nnmy4.get()); // explicit NotNull<MyPtr<int>> --> int* + f_i(nnmy4.get().get());// doubly-explicit NotNull<MyPtr<int>> --> int* + + // MyPtr<int> parameter + f_my(&i4); // implicit int* --> MyPtr<int> + f_my(my4); // identity MyPtr<int> --> MyPtr<int> + f_my(my4.get()); // explicit MyPtr<int> --> MyPtr<int> + //f_my(nni4); // no implicit NotNull<int*> --> MyPtr<int> + f_my(nni4.get()); // explicit NotNull<int*> --> MyPtr<int> + f_my(nnmy4); // implicit NotNull<MyPtr<int>> --> MyPtr<int> + f_my(nnmy4.get()); // explicit NotNull<MyPtr<int>> --> MyPtr<int> + f_my(nnmy4.get().get());// doubly-explicit NotNull<MyPtr<int>> --> MyPtr<int> + + // NotNull<int*> parameter + f_nni(nni4); // identity NotNull<int*> --> NotNull<int*> + f_nni(nnmy4); // implicit NotNull<MyPtr<int>> --> NotNull<int*> + + // NotNull<MyPtr<int>> parameter + f_nnmy(nni4); // implicit NotNull<int*> --> NotNull<MyPtr<int>> + f_nnmy(nnmy4); // identity NotNull<MyPtr<int>> --> NotNull<MyPtr<int>> + + //CHECK(nni4); // disallow boolean conversion / unary expression usage + //CHECK(nnmy4); // ditto + + // '->' dereferencing. + Blah blah; + MyPtr<Blah> myblah = &blah; + NotNull<Blah*> nnblah = WrapNotNull(&blah); + NotNull<MyPtr<Blah>> nnmyblah = WrapNotNull(myblah); + (&blah)->blah(); // int* + myblah->blah(); // MyPtr<int> + nnblah->blah(); // NotNull<int*> + nnmyblah->blah(); // NotNull<MyPtr<int>> + + (&blah)->mX = 1; + CHECK((&blah)->mX == 1); + myblah->mX = 2; + CHECK(myblah->mX == 2); + nnblah->mX = 3; + CHECK(nnblah->mX == 3); + nnmyblah->mX = 4; + CHECK(nnmyblah->mX == 4); + + // '*' dereferencing (lvalues and rvalues) + *(&i4) = 7; // int* + CHECK(*(&i4) == 7); + *my4 = 6; // MyPtr<int> + CHECK(*my4 == 6); + *nni4 = 5; // NotNull<int*> + CHECK(*nni4 == 5); + *nnmy4 = 4; // NotNull<MyPtr<int>> + CHECK(*nnmy4 == 4); + + // Non-null arrays. + static const int N = 20; + int a[N]; + NotNull<int*> nna = WrapNotNull(a); + for (int i = 0; i < N; i++) { + nna[i] = i; + } + for (int i = 0; i < N; i++) { + nna[i] *= 2; + } + for (int i = 0; i < N; i++) { + CHECK(nna[i] == i * 2); + } +} + +void f_ref(NotNull<MyRefType*> aR) +{ + NotNull<RefPtr<MyRefType>> r = aR; +} + +void +TestNotNullWithRefPtr() +{ + // This MyRefType object will have a maximum refcount of 5. + NotNull<RefPtr<MyRefType>> r1 = WrapNotNull(new MyRefType(5)); + + // At this point the refcount is 1. + + NotNull<RefPtr<MyRefType>> r2 = r1; + + // At this point the refcount is 2. + + NotNull<MyRefType*> r3 = r2; + (void)r3; + + // At this point the refcount is still 2. + + RefPtr<MyRefType> r4 = r2; + mozilla::Unused << r4; + + // At this point the refcount is 3. + + RefPtr<MyRefType> r5 = r3.get(); + mozilla::Unused << r5; + + // At this point the refcount is 4. + + // No change to the refcount occurs because of the argument passing. Within + // f_ref() the refcount temporarily hits 5, due to the local RefPtr. + f_ref(r2); + + // At this point the refcount is 4. + + // At function's end all RefPtrs are destroyed and the refcount drops to 0 + // and the MyRefType is destroyed. +} + +int +main() +{ + TestNotNullWithMyPtr(); + TestNotNullWithRefPtr(); + + return 0; +} + diff --git a/mfbt/tests/TestPair.cpp b/mfbt/tests/TestPair.cpp new file mode 100644 index 000000000..f1fa9c554 --- /dev/null +++ b/mfbt/tests/TestPair.cpp @@ -0,0 +1,83 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Pair.h" +#include "mozilla/TypeTraits.h" + +using mozilla::IsSame; +using mozilla::MakePair; +using mozilla::Pair; + +// Sizes aren't part of the guaranteed Pair interface, but we want to verify our +// attempts at compactness through EBO are moderately functional, *somewhere*. +#define INSTANTIATE(T1, T2, name, size) \ + Pair<T1, T2> name##_1(T1(0), T2(0)); \ + static_assert(sizeof(name##_1.first()) > 0, \ + "first method should work on Pair<" #T1 ", " #T2 ">"); \ + static_assert(sizeof(name##_1.second()) > 0, \ + "second method should work on Pair<" #T1 ", " #T2 ">"); \ + static_assert(sizeof(name##_1) == (size), \ + "Pair<" #T1 ", " #T2 "> has an unexpected size"); \ + Pair<T2, T1> name##_2(T2(0), T1(0)); \ + static_assert(sizeof(name##_2.first()) > 0, \ + "first method should work on Pair<" #T2 ", " #T1 ">"); \ + static_assert(sizeof(name##_2.second()) > 0, \ + "second method should work on Pair<" #T2 ", " #T1 ">"); \ + static_assert(sizeof(name##_2) == (size), \ + "Pair<" #T2 ", " #T1 "> has an unexpected size"); + +INSTANTIATE(int, int, prim1, 2 * sizeof(int)); +INSTANTIATE(int, long, prim2, 2 * sizeof(long)); + +struct EmptyClass { explicit EmptyClass(int) {} }; +struct NonEmpty { char mC; explicit NonEmpty(int) {} }; + +INSTANTIATE(int, EmptyClass, both1, sizeof(int)); +INSTANTIATE(int, NonEmpty, both2, 2 * sizeof(int)); +INSTANTIATE(EmptyClass, NonEmpty, both3, 1); + +struct A { char dummy; explicit A(int) {} }; +struct B : A { explicit B(int aI) : A(aI) {} }; + +INSTANTIATE(A, A, class1, 2); +INSTANTIATE(A, B, class2, 2); +INSTANTIATE(A, EmptyClass, class3, 1); + +struct OtherEmpty : EmptyClass { explicit OtherEmpty(int aI) : EmptyClass(aI) {} }; + +// C++11 requires distinct objects of the same type, within the same "most +// derived object", to have different addresses. Pair allocates its elements as +// two bases, a base and a member, or two members. If the two elements have +// non-zero size or are unrelated, no big deal. But if they're both empty and +// related, something -- possibly both -- must be inflated. Exactly which are +// inflated depends which PairHelper specialization is used. We could +// potentially assert something about size for this case, but whatever we could +// assert would be very finicky. Plus it's two empty classes -- hardly likely. +// So don't bother trying to assert anything about this case. +//INSTANTIATE(EmptyClass, OtherEmpty, class4, ...something finicky...); + +int +main() +{ + A a(0); + B b(0); + const A constA(0); + const B constB(0); + + // Check that MakePair generates Pair objects of the correct types. + static_assert(IsSame<decltype(MakePair(A(0), B(0))), Pair<A, B>>::value, + "MakePair should strip rvalue references"); + static_assert(IsSame<decltype(MakePair(a, b)), Pair<A, B>>::value, + "MakePair should strip lvalue references"); + static_assert(IsSame<decltype(MakePair(constA, constB)), Pair<A, B>>::value, + "MakePair should strip CV-qualifiers"); + + // Check that copy assignment and move assignment work. + a = constA; + a = A(0); + + return 0; +} diff --git a/mfbt/tests/TestPoisonArea.cpp b/mfbt/tests/TestPoisonArea.cpp new file mode 100644 index 000000000..6f1b61ed3 --- /dev/null +++ b/mfbt/tests/TestPoisonArea.cpp @@ -0,0 +1,549 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. + */ + +/* Code in this file needs to be kept in sync with code in nsPresArena.cpp. + * + * We want to use a fixed address for frame poisoning so that it is readily + * identifiable in crash dumps. Whether such an address is available + * without any special setup depends on the system configuration. + * + * All current 64-bit CPUs (with the possible exception of PowerPC64) + * reserve the vast majority of the virtual address space for future + * hardware extensions; valid addresses must be below some break point + * between 2**48 and 2**54, depending on exactly which chip you have. Some + * chips (notably amd64) also allow the use of the *highest* 2**48 -- 2**54 + * addresses. Thus, if user space pointers are 64 bits wide, we can just + * use an address outside this range, and no more is required. To + * accommodate the chips that allow very high addresses to be valid, the + * value chosen is close to 2**63 (that is, in the middle of the space). + * + * In most cases, a purely 32-bit operating system must reserve some + * fraction of the address space for its own use. Contemporary 32-bit OSes + * tend to take the high gigabyte or so (0xC000_0000 on up). If we can + * prove that high addresses are reserved to the kernel, we can use an + * address in that region. Unfortunately, not all 32-bit OSes do this; + * OSX 10.4 might not, and it is unclear what mobile OSes are like + * (some 32-bit CPUs make it very easy for the kernel to exist in its own + * private address space). + * + * Furthermore, when a 32-bit user space process is running on a 64-bit + * kernel, the operating system has no need to reserve any of the space that + * the process can see, and generally does not do so. This is the scenario + * of greatest concern, since it covers all contemporary OSX iterations + * (10.5+) as well as Windows Vista and 7 on newer amd64 hardware. Linux on + * amd64 is generally run as a pure 64-bit environment, but its 32-bit + * compatibility mode also has this property. + * + * Thus, when user space pointers are 32 bits wide, we need to validate + * our chosen address, and possibly *make* it a good poison address by + * allocating a page around it and marking it inaccessible. The algorithm + * for this is: + * + * 1. Attempt to make the page surrounding the poison address a reserved, + * inaccessible memory region using OS primitives. On Windows, this is + * done with VirtualAlloc(MEM_RESERVE); on Unix, mmap(PROT_NONE). + * + * 2. If mmap/VirtualAlloc failed, there are two possible reasons: either + * the region is reserved to the kernel and no further action is + * required, or there is already usable memory in this area and we have + * to pick a different address. The tricky part is knowing which case + * we have, without attempting to access the region. On Windows, we + * rely on GetSystemInfo()'s reported upper and lower bounds of the + * application memory area. On Unix, there is nothing devoted to the + * purpose, but seeing if madvise() fails is close enough (it *might* + * disrupt someone else's use of the memory region, but not by as much + * as anything else available). + * + * Be aware of these gotchas: + * + * 1. We cannot use mmap() with MAP_FIXED. MAP_FIXED is defined to + * _replace_ any existing mapping in the region, if necessary to satisfy + * the request. Obviously, as we are blindly attempting to acquire a + * page at a constant address, we must not do this, lest we overwrite + * someone else's allocation. + * + * 2. For the same reason, we cannot blindly use mprotect() if mmap() fails. + * + * 3. madvise() may fail when applied to a 'magic' memory region provided as + * a kernel/user interface. Fortunately, the only such case I know about + * is the "vsyscall" area (not to be confused with the "vdso" area) for + * *64*-bit processes on Linux - and we don't even run this code for + * 64-bit processes. + * + * 4. VirtualQuery() does not produce any useful information if + * applied to kernel memory - in fact, it doesn't write its output + * at all. Thus, it is not used here. + */ + +#include "mozilla/IntegerPrintfMacros.h" + +// MAP_ANON(YMOUS) is not in any standard. Add defines as necessary. +#define _GNU_SOURCE 1 +#define _DARWIN_C_SOURCE 1 + +#include <stddef.h> + +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#ifdef _WIN32 +#include <windows.h> +#else +#include <sys/types.h> +#include <fcntl.h> +#include <signal.h> +#include <unistd.h> +#include <sys/stat.h> +#include <sys/wait.h> + +#include <sys/mman.h> +#ifndef MAP_ANON +#ifdef MAP_ANONYMOUS +#define MAP_ANON MAP_ANONYMOUS +#else +#error "Don't know how to get anonymous memory" +#endif +#endif +#endif + +#define SIZxPTR ((int)(sizeof(uintptr_t)*2)) + +/* This program assumes that a whole number of return instructions fit into + * 32 bits, and that 32-bit alignment is sufficient for a branch destination. + * For architectures where this is not true, fiddling with RETURN_INSTR_TYPE + * can be enough. + */ + +#if defined __i386__ || defined __x86_64__ || \ + defined __i386 || defined __x86_64 || \ + defined _M_IX86 || defined _M_AMD64 +#define RETURN_INSTR 0xC3C3C3C3 /* ret; ret; ret; ret */ + +#elif defined __arm__ || defined _M_ARM +#define RETURN_INSTR 0xE12FFF1E /* bx lr */ + +// PPC has its own style of CPU-id #defines. There is no Windows for +// PPC as far as I know, so no _M_ variant. +#elif defined _ARCH_PPC || defined _ARCH_PWR || defined _ARCH_PWR2 +#define RETURN_INSTR 0x4E800020 /* blr */ + +#elif defined __sparc || defined __sparcv9 +#define RETURN_INSTR 0x81c3e008 /* retl */ + +#elif defined __alpha +#define RETURN_INSTR 0x6bfa8001 /* ret */ + +#elif defined __hppa +#define RETURN_INSTR 0xe840c002 /* bv,n r0(rp) */ + +#elif defined __mips +#define RETURN_INSTR 0x03e00008 /* jr ra */ + +#ifdef __MIPSEL +/* On mipsel, jr ra needs to be followed by a nop. + 0x03e00008 as a 64 bits integer just does that */ +#define RETURN_INSTR_TYPE uint64_t +#endif + +#elif defined __s390__ +#define RETURN_INSTR 0x07fe0000 /* br %r14 */ + +#elif defined __aarch64__ +#define RETURN_INSTR 0xd65f03c0 /* ret */ + +#elif defined __ia64 +struct ia64_instr { uint32_t mI[4]; }; +static const ia64_instr _return_instr = + {{ 0x00000011, 0x00000001, 0x80000200, 0x00840008 }}; /* br.ret.sptk.many b0 */ + +#define RETURN_INSTR _return_instr +#define RETURN_INSTR_TYPE ia64_instr + +#else +#error "Need return instruction for this architecture" +#endif + +#ifndef RETURN_INSTR_TYPE +#define RETURN_INSTR_TYPE uint32_t +#endif + +// Miscellaneous Windows/Unix portability gumph + +#ifdef _WIN32 +// Uses of this function deliberately leak the string. +static LPSTR +StrW32Error(DWORD aErrcode) +{ + LPSTR errmsg; + FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | + FORMAT_MESSAGE_FROM_SYSTEM | + FORMAT_MESSAGE_IGNORE_INSERTS, + nullptr, aErrcode, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), + (LPSTR)&errmsg, 0, nullptr); + + // FormatMessage puts an unwanted newline at the end of the string + size_t n = strlen(errmsg)-1; + while (errmsg[n] == '\r' || errmsg[n] == '\n') { + n--; + } + errmsg[n+1] = '\0'; + return errmsg; +} +#define LastErrMsg() (StrW32Error(GetLastError())) + +// Because we use VirtualAlloc in MEM_RESERVE mode, the "page size" we want +// is the allocation granularity. +static SYSTEM_INFO sInfo_; + +static inline uint32_t +PageSize() +{ + return sInfo_.dwAllocationGranularity; +} + +static void* +ReserveRegion(uintptr_t aRequest, bool aAccessible) +{ + return VirtualAlloc((void*)aRequest, PageSize(), + aAccessible ? MEM_RESERVE|MEM_COMMIT : MEM_RESERVE, + aAccessible ? PAGE_EXECUTE_READWRITE : PAGE_NOACCESS); +} + +static void +ReleaseRegion(void* aPage) +{ + VirtualFree(aPage, PageSize(), MEM_RELEASE); +} + +static bool +ProbeRegion(uintptr_t aPage) +{ + return aPage >= (uintptr_t)sInfo_.lpMaximumApplicationAddress && + aPage + PageSize() >= (uintptr_t)sInfo_.lpMaximumApplicationAddress; +} + +static bool +MakeRegionExecutable(void*) +{ + return false; +} + +#undef MAP_FAILED +#define MAP_FAILED 0 + +#else // Unix + +#define LastErrMsg() (strerror(errno)) + +static unsigned long gUnixPageSize; + +static inline unsigned long +PageSize() +{ + return gUnixPageSize; +} + +static void* +ReserveRegion(uintptr_t aRequest, bool aAccessible) +{ + return mmap(reinterpret_cast<void*>(aRequest), PageSize(), + aAccessible ? PROT_READ|PROT_WRITE : PROT_NONE, + MAP_PRIVATE|MAP_ANON, -1, 0); +} + +static void +ReleaseRegion(void* aPage) +{ + munmap(aPage, PageSize()); +} + +static bool +ProbeRegion(uintptr_t aPage) +{ + return !!madvise(reinterpret_cast<void*>(aPage), PageSize(), MADV_NORMAL); +} + +static int +MakeRegionExecutable(void* aPage) +{ + return mprotect((caddr_t)aPage, PageSize(), PROT_READ|PROT_WRITE|PROT_EXEC); +} + +#endif + +static uintptr_t +ReservePoisonArea() +{ + if (sizeof(uintptr_t) == 8) { + // Use the hardware-inaccessible region. + // We have to avoid 64-bit constants and shifts by 32 bits, since this + // code is compiled in 32-bit mode, although it is never executed there. + uintptr_t result = (((uintptr_t(0x7FFFFFFFu) << 31) << 1 | + uintptr_t(0xF0DEAFFFu)) & + ~uintptr_t(PageSize()-1)); + printf("INFO | poison area assumed at 0x%.*" PRIxPTR "\n", SIZxPTR, result); + return result; + } + + // First see if we can allocate the preferred poison address from the OS. + uintptr_t candidate = (0xF0DEAFFF & ~(PageSize() - 1)); + void* result = ReserveRegion(candidate, false); + if (result == reinterpret_cast<void*>(candidate)) { + // success - inaccessible page allocated + printf("INFO | poison area allocated at 0x%.*" PRIxPTR + " (preferred addr)\n", SIZxPTR, reinterpret_cast<uintptr_t>(result)); + return candidate; + } + + // That didn't work, so see if the preferred address is within a range + // of permanently inacessible memory. + if (ProbeRegion(candidate)) { + // success - selected page cannot be usable memory + if (result != MAP_FAILED) { + ReleaseRegion(result); + } + printf("INFO | poison area assumed at 0x%.*" PRIxPTR + " (preferred addr)\n", SIZxPTR, candidate); + return candidate; + } + + // The preferred address is already in use. Did the OS give us a + // consolation prize? + if (result != MAP_FAILED) { + uintptr_t ures = reinterpret_cast<uintptr_t>(result); + printf("INFO | poison area allocated at 0x%.*" PRIxPTR + " (consolation prize)\n", SIZxPTR, ures); + return ures; + } + + // It didn't, so try to allocate again, without any constraint on + // the address. + result = ReserveRegion(0, false); + if (result != MAP_FAILED) { + uintptr_t ures = reinterpret_cast<uintptr_t>(result); + printf("INFO | poison area allocated at 0x%.*" PRIxPTR + " (fallback)\n", SIZxPTR, ures); + return ures; + } + + printf("ERROR | no usable poison area found\n"); + return 0; +} + +/* The "positive control" area confirms that we can allocate a page with the + * proper characteristics. + */ +static uintptr_t +ReservePositiveControl() +{ + + void* result = ReserveRegion(0, false); + if (result == MAP_FAILED) { + printf("ERROR | allocating positive control | %s\n", LastErrMsg()); + return 0; + } + printf("INFO | positive control allocated at 0x%.*" PRIxPTR "\n", + SIZxPTR, (uintptr_t)result); + return (uintptr_t)result; +} + +/* The "negative control" area confirms that our probe logic does detect a + * page that is readable, writable, or executable. + */ +static uintptr_t +ReserveNegativeControl() +{ + void* result = ReserveRegion(0, true); + if (result == MAP_FAILED) { + printf("ERROR | allocating negative control | %s\n", LastErrMsg()); + return 0; + } + + // Fill the page with return instructions. + RETURN_INSTR_TYPE* p = reinterpret_cast<RETURN_INSTR_TYPE*>(result); + RETURN_INSTR_TYPE* limit = + reinterpret_cast<RETURN_INSTR_TYPE*>( + reinterpret_cast<char*>(result) + PageSize()); + while (p < limit) { + *p++ = RETURN_INSTR; + } + + // Now mark it executable as well as readable and writable. + // (mmap(PROT_EXEC) may fail when applied to anonymous memory.) + + if (MakeRegionExecutable(result)) { + printf("ERROR | making negative control executable | %s\n", LastErrMsg()); + return 0; + } + + printf("INFO | negative control allocated at 0x%.*" PRIxPTR "\n", + SIZxPTR, (uintptr_t)result); + return (uintptr_t)result; +} + +static void +JumpTo(uintptr_t aOpaddr) +{ +#ifdef __ia64 + struct func_call + { + uintptr_t mFunc; + uintptr_t mGp; + } call = { aOpaddr, }; + ((void (*)())&call)(); +#else + ((void (*)())aOpaddr)(); +#endif +} + +#ifdef _WIN32 +static BOOL +IsBadExecPtr(uintptr_t aPtr) +{ + BOOL ret = false; + +#ifdef _MSC_VER + __try { + JumpTo(aPtr); + } __except (EXCEPTION_EXECUTE_HANDLER) { + ret = true; + } +#else + printf("INFO | exec test not supported on MinGW build\n"); + // We do our best + ret = IsBadReadPtr((const void*)aPtr, 1); +#endif + return ret; +} +#endif + +/* Test each page. */ +static bool +TestPage(const char* aPageLabel, uintptr_t aPageAddr, int aShouldSucceed) +{ + const char* oplabel; + uintptr_t opaddr; + + bool failed = false; + for (unsigned int test = 0; test < 3; test++) { + switch (test) { + // The execute test must be done before the write test, because the + // write test will clobber memory at the target address. + case 0: oplabel = "reading"; opaddr = aPageAddr + PageSize()/2 - 1; break; + case 1: oplabel = "executing"; opaddr = aPageAddr + PageSize()/2; break; + case 2: oplabel = "writing"; opaddr = aPageAddr + PageSize()/2 - 1; break; + default: abort(); + } + +#ifdef _WIN32 + BOOL badptr; + + switch (test) { + case 0: badptr = IsBadReadPtr((const void*)opaddr, 1); break; + case 1: badptr = IsBadExecPtr(opaddr); break; + case 2: badptr = IsBadWritePtr((void*)opaddr, 1); break; + default: abort(); + } + + if (badptr) { + if (aShouldSucceed) { + printf("TEST-UNEXPECTED-FAIL | %s %s\n", oplabel, aPageLabel); + failed = true; + } else { + printf("TEST-PASS | %s %s\n", oplabel, aPageLabel); + } + } else { + // if control reaches this point the probe succeeded + if (aShouldSucceed) { + printf("TEST-PASS | %s %s\n", oplabel, aPageLabel); + } else { + printf("TEST-UNEXPECTED-FAIL | %s %s\n", oplabel, aPageLabel); + failed = true; + } + } +#else + pid_t pid = fork(); + if (pid == -1) { + printf("ERROR | %s %s | fork=%s\n", oplabel, aPageLabel, + LastErrMsg()); + exit(2); + } else if (pid == 0) { + volatile unsigned char scratch; + switch (test) { + case 0: scratch = *(volatile unsigned char*)opaddr; break; + case 1: JumpTo(opaddr); break; + case 2: *(volatile unsigned char*)opaddr = 0; break; + default: abort(); + } + (void)scratch; + _exit(0); + } else { + int status; + if (waitpid(pid, &status, 0) != pid) { + printf("ERROR | %s %s | wait=%s\n", oplabel, aPageLabel, + LastErrMsg()); + exit(2); + } + + if (WIFEXITED(status) && WEXITSTATUS(status) == 0) { + if (aShouldSucceed) { + printf("TEST-PASS | %s %s\n", oplabel, aPageLabel); + } else { + printf("TEST-UNEXPECTED-FAIL | %s %s | unexpected successful exit\n", + oplabel, aPageLabel); + failed = true; + } + } else if (WIFEXITED(status)) { + printf("ERROR | %s %s | unexpected exit code %d\n", + oplabel, aPageLabel, WEXITSTATUS(status)); + exit(2); + } else if (WIFSIGNALED(status)) { + if (aShouldSucceed) { + printf("TEST-UNEXPECTED-FAIL | %s %s | unexpected signal %d\n", + oplabel, aPageLabel, WTERMSIG(status)); + failed = true; + } else { + printf("TEST-PASS | %s %s | signal %d (as expected)\n", + oplabel, aPageLabel, WTERMSIG(status)); + } + } else { + printf("ERROR | %s %s | unexpected exit status %d\n", + oplabel, aPageLabel, status); + exit(2); + } + } +#endif + } + return failed; +} + +int +main() +{ +#ifdef _WIN32 + GetSystemInfo(&sInfo_); +#else + gUnixPageSize = sysconf(_SC_PAGESIZE); +#endif + + uintptr_t ncontrol = ReserveNegativeControl(); + uintptr_t pcontrol = ReservePositiveControl(); + uintptr_t poison = ReservePoisonArea(); + + if (!ncontrol || !pcontrol || !poison) { + return 2; + } + + bool failed = false; + failed |= TestPage("negative control", ncontrol, 1); + failed |= TestPage("positive control", pcontrol, 0); + failed |= TestPage("poison area", poison, 0); + + return failed ? 1 : 0; +} diff --git a/mfbt/tests/TestRange.cpp b/mfbt/tests/TestRange.cpp new file mode 100644 index 000000000..419c1cc26 --- /dev/null +++ b/mfbt/tests/TestRange.cpp @@ -0,0 +1,23 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Range.h" +#include "mozilla/TypeTraits.h" + +using mozilla::IsConvertible; +using mozilla::Range; + +static_assert(IsConvertible<Range<int>, Range<const int>>::value, + "Range should convert into const"); +static_assert(!IsConvertible<Range<const int>, Range<int>>::value, + "Range should not drop const in conversion"); + +// We need a proper program so we have someplace to hang the static_asserts. +int +main() +{ + return 0; +} diff --git a/mfbt/tests/TestRefPtr.cpp b/mfbt/tests/TestRefPtr.cpp new file mode 100644 index 000000000..4d9e712bd --- /dev/null +++ b/mfbt/tests/TestRefPtr.cpp @@ -0,0 +1,139 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/RefPtr.h" +#include "mozilla/RefCounted.h" + +using mozilla::RefCounted; + +class Foo : public RefCounted<Foo> +{ +public: + MOZ_DECLARE_REFCOUNTED_TYPENAME(Foo) + + Foo() : mDead(false) {} + + static int sNumDestroyed; + + ~Foo() + { + MOZ_ASSERT(!mDead); + mDead = true; + sNumDestroyed++; + } + +private: + bool mDead; +}; +int Foo::sNumDestroyed; + +struct Bar : public Foo {}; + +already_AddRefed<Foo> +NewFoo() +{ + RefPtr<Foo> f(new Foo()); + return f.forget(); +} + +already_AddRefed<Foo> +NewBar() +{ + RefPtr<Bar> bar = new Bar(); + return bar.forget(); +} + +void +GetNewFoo(Foo** aFoo) +{ + *aFoo = new Bar(); + // Kids, don't try this at home + (*aFoo)->AddRef(); +} + +void +GetNewFoo(RefPtr<Foo>* aFoo) +{ + *aFoo = new Bar(); +} + +already_AddRefed<Foo> +GetNullFoo() +{ + return 0; +} + +int +main() +{ + MOZ_RELEASE_ASSERT(0 == Foo::sNumDestroyed); + { + RefPtr<Foo> f = new Foo(); + MOZ_RELEASE_ASSERT(f->refCount() == 1); + } + MOZ_RELEASE_ASSERT(1 == Foo::sNumDestroyed); + + { + RefPtr<Foo> f1 = NewFoo(); + RefPtr<Foo> f2(NewFoo()); + MOZ_RELEASE_ASSERT(1 == Foo::sNumDestroyed); + } + MOZ_RELEASE_ASSERT(3 == Foo::sNumDestroyed); + + { + RefPtr<Foo> b = NewBar(); + MOZ_RELEASE_ASSERT(3 == Foo::sNumDestroyed); + } + MOZ_RELEASE_ASSERT(4 == Foo::sNumDestroyed); + + { + RefPtr<Foo> f1; + { + f1 = new Foo(); + RefPtr<Foo> f2(f1); + RefPtr<Foo> f3 = f2; + MOZ_RELEASE_ASSERT(4 == Foo::sNumDestroyed); + } + MOZ_RELEASE_ASSERT(4 == Foo::sNumDestroyed); + } + MOZ_RELEASE_ASSERT(5 == Foo::sNumDestroyed); + + { + { + RefPtr<Foo> f = new Foo(); + RefPtr<Foo> g = f.forget(); + } + MOZ_RELEASE_ASSERT(6 == Foo::sNumDestroyed); + } + + { + RefPtr<Foo> f = new Foo(); + GetNewFoo(getter_AddRefs(f)); + MOZ_RELEASE_ASSERT(7 == Foo::sNumDestroyed); + } + MOZ_RELEASE_ASSERT(8 == Foo::sNumDestroyed); + + { + RefPtr<Foo> f = new Foo(); + GetNewFoo(&f); + MOZ_RELEASE_ASSERT(9 == Foo::sNumDestroyed); + } + MOZ_RELEASE_ASSERT(10 == Foo::sNumDestroyed); + + { + RefPtr<Foo> f1 = new Bar(); + } + MOZ_RELEASE_ASSERT(11 == Foo::sNumDestroyed); + + { + RefPtr<Foo> f = GetNullFoo(); + MOZ_RELEASE_ASSERT(11 == Foo::sNumDestroyed); + } + MOZ_RELEASE_ASSERT(11 == Foo::sNumDestroyed); + + return 0; +} + diff --git a/mfbt/tests/TestRollingMean.cpp b/mfbt/tests/TestRollingMean.cpp new file mode 100644 index 000000000..bec77786f --- /dev/null +++ b/mfbt/tests/TestRollingMean.cpp @@ -0,0 +1,129 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/RollingMean.h" + +using mozilla::RollingMean; + +class MyClass +{ +public: + uint32_t mValue; + + explicit MyClass(uint32_t aValue = 0) : mValue(aValue) { } + + bool operator==(const MyClass& aOther) const + { + return mValue == aOther.mValue; + } + + MyClass operator+(const MyClass& aOther) const + { + return MyClass(mValue + aOther.mValue); + } + + MyClass operator-(const MyClass& aOther) const + { + return MyClass(mValue - aOther.mValue); + } + + MyClass operator/(uint32_t aDiv) const + { + return MyClass(mValue / aDiv); + } +}; + +class RollingMeanSuite +{ +public: + RollingMeanSuite() { } + + void runTests() { + testZero(); + testClear(); + testRolling(); + testClass(); + testMove(); + } + +private: + void testZero() + { + RollingMean<uint32_t, uint64_t> mean(3); + MOZ_RELEASE_ASSERT(mean.empty()); + } + + void testClear() + { + RollingMean<uint32_t, uint64_t> mean(3); + + mean.insert(4); + MOZ_RELEASE_ASSERT(mean.mean() == 4); + + mean.clear(); + MOZ_RELEASE_ASSERT(mean.empty()); + + mean.insert(3); + MOZ_RELEASE_ASSERT(mean.mean() == 3); + } + + void testRolling() + { + RollingMean<uint32_t, uint64_t> mean(3); + + mean.insert(10); + MOZ_RELEASE_ASSERT(mean.mean() == 10); + + mean.insert(20); + MOZ_RELEASE_ASSERT(mean.mean() == 15); + + mean.insert(35); + MOZ_RELEASE_ASSERT(mean.mean() == 21); + + mean.insert(5); + MOZ_RELEASE_ASSERT(mean.mean() == 20); + + mean.insert(10); + MOZ_RELEASE_ASSERT(mean.mean() == 16); + } + + void testClass() + { + RollingMean<MyClass, MyClass> mean(3); + + mean.insert(MyClass(4)); + MOZ_RELEASE_ASSERT(mean.mean() == MyClass(4)); + + mean.clear(); + MOZ_RELEASE_ASSERT(mean.empty()); + } + + void testMove() + { + RollingMean<uint32_t, uint64_t> mean(3); + mean = RollingMean<uint32_t, uint64_t>(4); + MOZ_RELEASE_ASSERT(mean.maxValues() == 4); + + mean.insert(10); + MOZ_RELEASE_ASSERT(mean.mean() == 10); + + mean = RollingMean<uint32_t, uint64_t>(3); + mean.insert(30); + mean.insert(40); + mean.insert(50); + mean.insert(60); + MOZ_RELEASE_ASSERT(mean.mean() == 50); + } +}; + +int +main() +{ + RollingMeanSuite suite; + suite.runTests(); + return 0; +} diff --git a/mfbt/tests/TestSHA1.cpp b/mfbt/tests/TestSHA1.cpp new file mode 100644 index 000000000..fd64df1ca --- /dev/null +++ b/mfbt/tests/TestSHA1.cpp @@ -0,0 +1,208 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/SHA1.h" + +using mozilla::SHA1Sum; + +static unsigned int gTestV[1024] = { + 0x048edc1a, 0x4345588c, 0x0ef03cbf, 0x1d6438f5, 0x094e0a1e, 0x68535f60, + 0x14e8c927, 0x60190043, 0x5d640ab7, 0x73dc7c62, 0x364223f9, 0x47320292, + 0x3924cae0, 0x5f6b26d3, 0x5efa04ef, 0x7aab361e, 0x2773b1aa, 0x1631b07d, + 0x385b5dd1, 0x26c809b0, 0x28ad3a9f, 0x0315292a, 0x1a544e67, 0x1e79dcb9, + 0x787683e8, 0x3a591c75, 0x1dd338c7, 0x01c539e5, 0x1c15b23e, 0x0697c25c, + 0x4df5fd45, 0x672aa324, 0x39f74e6e, 0x269cdd5f, 0x087b6fce, 0x293509db, + 0x0aef54a9, 0x210c4cc5, 0x29d6dc4a, 0x16320825, 0x3ab7b181, 0x56d6fd25, + 0x6837fda2, 0x3e7994c2, 0x37f77529, 0x48c85472, 0x424fd84d, 0x00aba7fa, + 0x6d8475de, 0x354634a7, 0x0c73bb49, 0x0a335de6, 0x0a9ea542, 0x5ffb31f1, + 0x00a6a3f2, 0x76b14a03, 0x1e436a37, 0x173b766a, 0x33cf3ca0, 0x34eb0f1a, + 0x4ca073ee, 0x27591fe6, 0x5eaf3356, 0x10c24493, 0x1bad88b6, 0x676f2309, + 0x7f5e2d91, 0x74bd4c83, 0x66549b43, 0x52ffdf24, 0x2dfa0a83, 0x7c3e1cbf, + 0x1edf87fc, 0x1f6fa930, 0x7c29bc74, 0x374bcd2f, 0x5b43de94, 0x0d09a3a6, + 0x7437ecb0, 0x635117f8, 0x2aa78f65, 0x2c788958, 0x098cb9f3, 0x13ed5b3f, + 0x41b7c7ba, 0x696b2d88, 0x42e20d63, 0x69585b1d, 0x4a9b027c, 0x0c761cba, + 0x563bdbc4, 0x3bde2f5b, 0x0bab9730, 0x7740104c, 0x11641702, 0x26f03c32, + 0x011a87c6, 0x2c5e4e6c, 0x46c34200, 0x6a167e84, 0x34205728, 0x0e8a6152, + 0x0014604b, 0x6793bacd, 0x442bca9c, 0x6f2018ce, 0x4313e07e, 0x77f2c69c, + 0x62621441, 0x47bf6358, 0x59c45e04, 0x16ba3426, 0x6ac0c19d, 0x20218c6b, + 0x510b4ddc, 0x585f6c9d, 0x1ed02b0c, 0x366bf0a9, 0x131c7f59, 0x0ebcd320, + 0x00ca858a, 0x5efbcb77, 0x2a7a1859, 0x64bb5afd, 0x76258886, 0x6505c895, + 0x602cfa32, 0x17040942, 0x783df744, 0x3838e0ae, 0x6a021e39, 0x4c8c9c5a, + 0x4a5e96b6, 0x10f4477d, 0x247fda4f, 0x4c390400, 0x0cbe048c, 0x7b547d26, + 0x1e2e6897, 0x4ba7e01b, 0x5cfea1bb, 0x39a2d199, 0x45aee64a, 0x12615500, + 0x0151615f, 0x1a9f5d33, 0x4542ed44, 0x101357eb, 0x35a16b1f, 0x3420b3e1, + 0x6442bac7, 0x1c0f2a8c, 0x68d642f1, 0x45744fc4, 0x048e60cb, 0x5f217f44, + 0x6cc7d151, 0x27f41984, 0x2d01eb09, 0x2bb15aea, 0x6dda49f8, 0x590dd6bc, + 0x280cc20b, 0x7e2592b5, 0x043642f0, 0x292b5d29, 0x2e0a9b69, 0x41162471, + 0x1e55db6b, 0x648b96fe, 0x05f8f9d1, 0x4a9d4cbb, 0x38517039, 0x2b0f8917, + 0x4d1e67bb, 0x713e0974, 0x64fdf214, 0x11223963, 0x2bd09d24, 0x19924092, + 0x4b4a70f0, 0x1ece6b03, 0x1780c9c1, 0x09b4c3ac, 0x58ac7e73, 0x5c9a4747, + 0x321f943b, 0x41167667, 0x3a19cf8c, 0x53f4144d, 0x03a498de, 0x6fb4b742, + 0x54d793cb, 0x7ee164e2, 0x501af74c, 0x43201e7f, 0x0ad581be, 0x497f046a, + 0x3b1d2a9f, 0x53b88eb0, 0x2c3a26c5, 0x5ae970ba, 0x7d7ee4ff, 0x471366c5, + 0x46119703, 0x3bfc2e58, 0x456d6c4f, 0x4b6bb181, 0x45d7c872, 0x0d023221, + 0x021176d1, 0x4195ad44, 0x4621ec90, 0x3ae68279, 0x57952f71, 0x1796080c, + 0x228077bb, 0x5e2b7fee, 0x3d71dd88, 0x4a651849, 0x7f1c8081, 0x04c333fc, + 0x1f99bff6, 0x11b7754c, 0x740be324, 0x069bf2e2, 0x0802f3e0, 0x371cf30e, + 0x1d44dda5, 0x6033b9e5, 0x5639a9b0, 0x6526bfff, 0x14d7d9b7, 0x4182b6a7, + 0x01a5fa76, 0x7aa5e581, 0x762465e6, 0x386b3a2e, 0x495a3ab0, 0x04421b2e, + 0x46e04591, 0x472af458, 0x6a007dd3, 0x2e8be484, 0x18660abe, 0x7969af82, + 0x5a242a83, 0x581b5f72, 0x5f0eff6d, 0x38aea98c, 0x2acb5853, 0x6d650b35, + 0x10b750d7, 0x18fdcd14, 0x09b4816c, 0x3ceef016, 0x6957153c, 0x27cf39fb, + 0x60e3495d, 0x381e1da6, 0x4b5be02d, 0x14b6f309, 0x6380c589, 0x1a31f436, + 0x4b5e50c1, 0x493ac048, 0x314baad1, 0x71e24ab7, 0x718af49c, 0x022f4658, + 0x1a419d5b, 0x1854610d, 0x2ec4e99a, 0x7096ce50, 0x5467ba00, 0x404aab4c, + 0x1a5ab015, 0x217580f7, 0x2d50071e, 0x71a9f437, 0x27f758b5, 0x11cd8b3f, + 0x63b089c9, 0x53c860c1, 0x2fa6b7d7, 0x61e54771, 0x5c0ba6b9, 0x3138f796, + 0x5c7359cd, 0x4c2c5654, 0x549d581c, 0x3129ebf7, 0x4958a248, 0x1a460541, + 0x68e64964, 0x597c0609, 0x57afcbab, 0x2f1c6479, 0x57a0ad5c, 0x5936938f, + 0x536a5cbe, 0x29aacf0b, 0x43eca70d, 0x6e7a3e4e, 0x563c1e3b, 0x32f23909, + 0x12faa42d, 0x28b0bbde, 0x797e2842, 0x1b827bdf, 0x0df96a6e, 0x542ef7f4, + 0x6226d368, 0x01cb4258, 0x77bcba08, 0x7e6dc041, 0x0571eda3, 0x0fdf5065, + 0x5c9b9f7a, 0x2b496dd6, 0x02d3b40b, 0x3a5752db, 0x4843a293, 0x6fdc9c3f, + 0x42963996, 0x39c9e4eb, 0x01db58ad, 0x7e79381c, 0x5bb207bb, 0x2df5de51, + 0x1549ec82, 0x64f01e70, 0x536eb0d0, 0x10fa6e03, 0x5b7f9a20, 0x2d8b625d, + 0x397410c7, 0x7778284e, 0x1ab75170, 0x254f304e, 0x395ba877, 0x0c2e2815, + 0x5c723dec, 0x63b91327, 0x7c5954b5, 0x67dd69a3, 0x21d220c7, 0x5a287fcd, + 0x0d0b9c59, 0x22444c9f, 0x6305cb43, 0x12f717cc, 0x77c11945, 0x0e79bda8, + 0x6e014391, 0x441d0179, 0x5e17dd2f, 0x53e57a5c, 0x692f4b9a, 0x76c1e94b, + 0x5a872d81, 0x044f7e7e, 0x0970844f, 0x25e34e73, 0x57865d3c, 0x640771d2, + 0x12d410ed, 0x1424e079, 0x3e1c7fd7, 0x0e89295a, 0x48dcf262, 0x55a29550, + 0x0fd4d360, 0x7494d449, 0x41e6f260, 0x2230d4e7, 0x5ad1cd49, 0x7f8dd428, + 0x7722b48a, 0x7a14848d, 0x2a83335a, 0x548c0d9b, 0x24f5d43b, 0x33a417cb, + 0x3061e078, 0x1a1bc935, 0x5aedb5df, 0x6755f3e4, 0x795e4cdb, 0x64dfcd1c, + 0x6d5164fc, 0x34a3df0e, 0x2cc92142, 0x2569127d, 0x130f3d86, 0x43617cc2, + 0x25eaf1fa, 0x044ae792, 0x4b47ee17, 0x6879ea87, 0x7eb455fa, 0x54481e19, + 0x13bba2f0, 0x6da3fe79, 0x19c306ff, 0x42591e38, 0x2b0e205d, 0x60bd48bc, + 0x550aa0ce, 0x2296a6ef, 0x551eb052, 0x76df1b8e, 0x242a2d22, 0x0ada0b06, + 0x58b661ec, 0x490bec94, 0x20bd7c59, 0x760de8c3, 0x7a048ee8, 0x44ba6dcd, + 0x3816abd9, 0x47e8527e, 0x2194a188, 0x6967a480, 0x7f7e2083, 0x0ec455f3, + 0x78198eab, 0x3d710773, 0x05969198, 0x76ffcffe, 0x54be4797, 0x11105781, + 0x3a851719, 0x516284b8, 0x4295de1c, 0x3905be43, 0x6d4e7d6a, 0x0877796d, + 0x0b9e986a, 0x5e2b853f, 0x7e6c79cd, 0x4a44a54c, 0x1e28b9a2, 0x5b1e408e, + 0x6a1c8eac, 0x62a87929, 0x4f075dac, 0x5c030e8c, 0x3df73ce9, 0x321c3c69, + 0x2325cc45, 0x4eaf0759, 0x486a31fb, 0x12d04b94, 0x714e15d5, 0x420d1910, + 0x092dc45b, 0x0119beac, 0x68b2bfdb, 0x74863a17, 0x3c7ab8e5, 0x035bc2df, + 0x4e7a7965, 0x017f58d6, 0x6414074e, 0x3a1e64ae, 0x2d6725d8, 0x0f22f82a, + 0x0a0affa0, 0x4159f31e, 0x4002cb9d, 0x234e393f, 0x6028169f, 0x3b804078, + 0x0c16e2e1, 0x0e198020, 0x24b13c40, 0x1ceb2143, 0x38dd4246, 0x6f483590, + 0x69b20a6e, 0x105580b1, 0x5d60f184, 0x065d18eb, 0x09a28739, 0x70345728, + 0x595a5934, 0x14a78a43, 0x449f05c7, 0x6556fcfc, 0x260bc0b2, 0x3afb600e, + 0x1f47bb91, 0x145c14b6, 0x541832fe, 0x54f10f23, 0x3013650e, 0x6c0d32ba, + 0x4f202c8d, 0x66bcc661, 0x6131dc7f, 0x04828b25, 0x1737565d, 0x520e967f, + 0x16cf0438, 0x6f2bc19e, 0x553c3dda, 0x356906b0, 0x333916d5, 0x2887c195, + 0x11e7440b, 0x6354f182, 0x06b2f977, 0x6d2c9a5c, 0x2d02bfb7, 0x74fafcf6, + 0x2b955161, 0x74035c38, 0x6e9bc991, 0x09a3a5b9, 0x460f416a, 0x11afabfc, + 0x66e32d10, 0x4a56ac6e, 0x6448afa8, 0x680b0044, 0x05d0e296, 0x49569eac, + 0x0adb563b, 0x4a9da168, 0x4f857004, 0x0f234600, 0x6db386ec, 0x280b94bf, + 0x7cd258a5, 0x6165fd88, 0x3bf2aac9, 0x2cb47c44, 0x2381c2a4, 0x4fe42552, + 0x21d4c81e, 0x24baa9af, 0x365231cb, 0x11b7fc81, 0x419748fb, 0x38ff637e, + 0x065f3365, 0x21f1aba8, 0x2df41ace, 0x5cec1d95, 0x22c078a8, 0x7bb894fc, + 0x2d66fc53, 0x7ed82ccc, 0x4485c9d7, 0x1af210fc, 0x5d2faa09, 0x3b33412e, + 0x79d12ea8, 0x7bb8103b, 0x5cea1a7b, 0x2779db45, 0x1250ed5b, 0x0c4d8964, + 0x6c18e9f5, 0x501ddc60, 0x3de43ae4, 0x6c0e8577, 0x0adfb426, 0x7ec718f5, + 0x1991f387, 0x101ccb9c, 0x632360b4, 0x7d52ce4d, 0x0b58c91c, 0x1fa59d53, + 0x0b0b48b0, 0x297315d0, 0x7f3132ff, 0x323b85d1, 0x2f852141, 0x23e84bdc, + 0x3732cb25, 0x1274eb57, 0x21a882c3, 0x095288a9, 0x2120e253, 0x617799ce, + 0x5e4926b3, 0x52575363, 0x696722e0, 0x509c9117, 0x3b60f14f, 0x423310fa, + 0x4e694e80, 0x000a647e, 0x453e283a, 0x3f1d21ef, 0x527c91f0, 0x7ac2e88a, + 0x1ba3b840, 0x1c3f253a, 0x04c40280, 0x437dc361, 0x7247859c, 0x61e5b34c, + 0x20746a53, 0x58cfc2df, 0x79edf48e, 0x5b48e723, 0x7b08baac, 0x1d1035ea, + 0x023fc918, 0x2de0427c, 0x71540904, 0x4030e8f5, 0x2b0961f6, 0x4ec98ef0, + 0x781076ee, 0x0dac959b, 0x16f66214, 0x273411e5, 0x02334297, 0x3b568cd1, + 0x7cf4e8c0, 0x0f4c2c91, 0x2d8dd28e, 0x4a7b3fb0, 0x237969ae, 0x363d6cb6, + 0x75fee60a, 0x5825f4df, 0x29f79f9d, 0x22de4f33, 0x2309590e, 0x1977c2bd, + 0x67f7bebe, 0x452b8330, 0x5dc70832, 0x5cddbea4, 0x59091e0b, 0x4d287830, + 0x2bbc2ce6, 0x420ee023, 0x02d6e086, 0x228a7a14, 0x48207207, 0x1d5ccc5a, + 0x37d32cdc, 0x50dc6508, 0x0b795304, 0x5b9fd543, 0x2a3f2925, 0x72e71606, + 0x0dc8ba42, 0x3279a910, 0x6bd2c2e2, 0x775065d8, 0x547c59a6, 0x4b5374cf, + 0x0c45cd18, 0x532096d6, 0x351c9bd1, 0x107fdce0, 0x3ae69075, 0x5dddd5de, + 0x3bb0ba8b, 0x0b1a0019, 0x6c226525, 0x109e9002, 0x312191be, 0x16fa3de8, + 0x4a5197aa, 0x0931b2d2, 0x79ee6e1b, 0x657a142b, 0x6ab74d38, 0x77440cff, + 0x11e37956, 0x5c335799, 0x269d3be3, 0x18923cfd, 0x4dd71b00, 0x77c58014, + 0x07145324, 0x1678546a, 0x5dfd4f6a, 0x207f4e13, 0x6b0a98c0, 0x015bc2cf, + 0x1636d8fe, 0x7bc5f038, 0x183a0661, 0x573ec5f3, 0x54cf2255, 0x2fcc905c, + 0x71bb70b9, 0x2b122a89, 0x59f86e5b, 0x5528273d, 0x464cf857, 0x27efdeec, + 0x1d0bcfcc, 0x64d7837f, 0x1e7a659a, 0x02aa611c, 0x53969ad5, 0x0e83f59f, + 0x50a6d11b, 0x79513c59, 0x0e5c3c98, 0x2ed7bbcf, 0x117de9d9, 0x375ec696, + 0x19c830aa, 0x66950511, 0x2b6dbbaa, 0x5ca18c9b, 0x0a487514, 0x6f44a887, + 0x6921bc6e, 0x3ef8130b, 0x26f6cde3, 0x686d7605, 0x6583553a, 0x29bcf7cc, + 0x55d42201, 0x1c93497c, 0x64c53231, 0x32088f6e, 0x381c5770, 0x617574d8, + 0x09757952, 0x1a616eb0, 0x1140e8aa, 0x0ff66ffb, 0x32039001, 0x5a455e7c, + 0x0027b906, 0x21cf154c, 0x67d3527f, 0x56fd7602, 0x150f8b25, 0x2ae8e4c8, + 0x0bf10aec, 0x3d26a40f, 0x5c4c8ffc, 0x3c291322, 0x737fd02c, 0x4b506209, + 0x484ddaa4, 0x00b44669, 0x5974bdd1, 0x7d39d617, 0x12995404, 0x48f00bbe, + 0x44f7c59a, 0x23cb9292, 0x6476f20b, 0x034fbd59, 0x2893161c, 0x1dbae8c0, + 0x50348c2e, 0x797f0957, 0x685ddeaf, 0x36fb8a2e, 0x0fceb6f4, 0x10347ab4, + 0x72720bfc, 0x292a4304, 0x0cbf8a27, 0x3cea6db7, 0x4b0c6b15, 0x57e8e716, + 0x4e9c54cc, 0x4fc7f7ca, 0x49a6d3e2, 0x10fc2df3, 0x73db387e, 0x72cb89c3, + 0x71dba437, 0x4b14048c, 0x6e1af265, 0x1084b213, 0x3842107d, 0x6ecdc171, + 0x647919b2, 0x41a80841, 0x7b387c76, 0x46bc094b, 0x331b312a, 0x2f140cc4, + 0x355d0a11, 0x19390200, 0x69b05263, 0x582963fa, 0x44897e31, 0x66a473f0, + 0x0374f08d, 0x35879e45, 0x5e1dd7ef, 0x34d6a311, 0x6e4e18eb, 0x7b44734b, + 0x0e421333, 0x3da026d8, 0x5becbf4b, 0x56db4a1f, 0x1f2089bc, 0x28c733f2, + 0x04b0975d, 0x6156f224, 0x12d1f40f, 0x7f4d30f4, 0x2c0b9861, 0x769a083b, + 0x739544fb, 0x1dbd1067, 0x0e8cd717, 0x4c246fb2, 0x115eff39, 0x19e22f2a, + 0x4563ba61, 0x5d33a617, 0x54af83cf, 0x030bde73, 0x54b4736d, 0x0f01dfec, + 0x08869c01, 0x4e9e4d7b, 0x4739855a, 0x62d964a3, 0x26948fde, 0x30adf212, + 0x1f57b400, 0x3766c914, 0x1e7f9d1c, 0x33258b59, 0x522ab2c2, 0x3dc99798, + 0x15f53fe2, 0x05636669, 0x354b59c3, 0x1c37ebd4, 0x0bb7ebf9, 0x0e4e87f9, + 0x680d3124, 0x2770d549, 0x0c5e112e, 0x74aaa7ed, 0x06c0b550, 0x342b5922, + 0x4532ab5b, 0x4257dbee, 0x087f32a9, 0x45ada3e3, 0x7a854272, 0x061625f2, + 0x47c85a91, 0x25ad375d, 0x2809bd9d, 0x168b9348, 0x4381b0a3, 0x6f2dc6ca, + 0x122e54f6, 0x6c3228a6, 0x653c1652, 0x60b60584, 0x1d304b77, 0x4cc74c58, + 0x087e3dd5, 0x79bd540e, 0x79ab7a70, 0x26fcd1c9, 0x342abaaf, 0x644716b0, + 0x01f076cb, 0x73628937, 0x20b01ff8, 0x5832b80b, 0x2f77fc92, 0x4468d962, + 0x2bac2679, 0x7f850778, 0x47d2997c, 0x02690cb7, 0x7de54951, 0x54d80b14, + 0x5e0c6854, 0x313cc749, 0x622b86ba, 0x38dbf6d3, 0x045d3e52, 0x574f87fd, + 0x09f1b078, 0x31784f71, 0x4f01dd2f, 0x1874c9f9, 0x5837c7af, 0x2372f768, + 0x531bd1e8, 0x61816c0b, 0x4592995f, 0x156463c0, 0x250c5afe, 0x40c83178, + 0x4396f6b7, 0x29bdbec0, 0x43ea8ca5, 0x5c474696, 0x2c869192, 0x2ff2f51a, + 0x7c963fe5, 0x294319c1, 0x019fbe26, 0x72fa8e68, 0x245ca463, 0x4ca88208, + 0x72ac845a, 0x25307181, 0x2cdf88f7, 0x0adbfebd, 0x2eea465b, 0x52e4eee0, + 0x084daacd, 0x717ce67e, 0x594087c2, 0x2b8ee5c7, 0x4558f811, 0x76b65ba4, + 0x5de05e09, 0x3db76e27, 0x3c75110d, 0x04ca67e7, 0x51cd6d09, 0x7b4e9c3e, + 0x7cdda4d2, 0x674fb021, 0x7d372d2d, 0x13f7978b, 0x5fb106b1, 0x034377d1, + 0x2e5336f3, 0x099bb17d, 0x04e6755e, 0x34f73c1e, 0x004e0a0d, 0x7f2c32e2, + 0x1fc8f910, 0x67d0859d, 0x76462b25, 0x59fa9a17, 0x028e53ef, 0x3d6d5fdd, + 0x79a4671e, 0x5cbec506, 0x2c23ee6d, 0x628a2c1e, 0x4dae87bd, 0x07a189ea, + 0x3a414a96, 0x5915f622, 0x6bea011e, 0x412674cf, 0x07ecc314, 0x6a7dbce8, + 0x7e176f10, 0x68e60d47, 0x079ea970, 0x79f3b55c, 0x65a46098, 0x56155533, + 0x7e5d0272, 0x795bfad5, 0x094da770, 0x05ba427c, 0x152e430e, 0x187d8470, + 0x08e607bc, 0x45ce5ef9, 0x654231ae, 0x38d8cb48, 0x605632f8, 0x25cf8ee9, + 0x11497170, 0x171a3b00, 0x0f103d49, 0x24826483, 0x2848e187, 0x7498919b, + 0x1bb788cb, 0x791ad5c7, 0x5129330e, 0x016c4436, 0x430f05bf, 0x1f06b5cd, + 0x62df1378, 0x0423b9b4, 0x0341acaf, 0x3189543c, 0x7b96b2ea, 0x6c4865c3, + 0x4cc7adc3, 0x78a2bff6, 0x642db7c7, 0x70d02300, 0x7cd43ac0, 0x4f5fe414, + 0x333b52c2, 0x500d3c74, 0x65782c01, 0x3f72a2c5, 0x278f59d8, 0x493bf7f8, + 0x16bf51a0, 0x6cc70ced, 0x6ed15979, 0x1a77abae, 0x08cadbb7, 0x2f2e0bc0, + 0x236f5e8d, 0x1a4b4495, 0x360bd008, 0x32227d40 +}; + +int +main() +{ + SHA1Sum sum; + SHA1Sum::Hash hash; + sum.update(reinterpret_cast<const uint8_t*>(gTestV), sizeof(gTestV)); + sum.finish(hash); + + static const uint8_t expected[20] = { + 0xc8, 0xf2, 0x09, 0x59, 0x4e, 0x64, 0x40, 0xaa, 0x7b, 0xf7, 0xb8, 0xe0, + 0xfa, 0x44, 0xb2, 0x31, 0x95, 0xad, 0x94, 0x81 + }; + + static_assert(sizeof(expected) == sizeof(SHA1Sum::Hash), + "expected-data size should be the same as the actual hash " + "size"); + + for (size_t i = 0; i < SHA1Sum::kHashSize; i++) { + MOZ_RELEASE_ASSERT(hash[i] == expected[i]); + } + + return 0; +} diff --git a/mfbt/tests/TestSaturate.cpp b/mfbt/tests/TestSaturate.cpp new file mode 100644 index 000000000..06573ba4a --- /dev/null +++ b/mfbt/tests/TestSaturate.cpp @@ -0,0 +1,215 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include <mozilla/Saturate.h> + +#include <mozilla/Assertions.h> + +#include <limits> + +using mozilla::detail::Saturate; + +#define A(a) MOZ_RELEASE_ASSERT(a, "Test \'" #a "\' failed.") + +static const unsigned long sNumOps = 32; + +template<typename T> +static T +StartValue() +{ + // Specialize |StartValue| for the given type. + A(false); +} + +template<> +int8_t +StartValue<int8_t>() +{ + return 0; +} + +template<> +int16_t +StartValue<int16_t>() +{ + return 0; +} + +template<> +int32_t +StartValue<int32_t>() +{ + return 0; +} + +template<> +uint8_t +StartValue<uint8_t>() +{ + // Picking a value near middle of uint8_t's range. + return static_cast<uint8_t>(std::numeric_limits<int8_t>::max()); +} + +template<> +uint16_t +StartValue<uint16_t>() +{ + // Picking a value near middle of uint16_t's range. + return static_cast<uint8_t>(std::numeric_limits<int16_t>::max()); +} + +template<> +uint32_t +StartValue<uint32_t>() +{ + // Picking a value near middle of uint32_t's range. + return static_cast<uint8_t>(std::numeric_limits<int32_t>::max()); +} + +// Add +// + +template<typename T> +static void +TestPrefixIncr() +{ + T value = StartValue<T>(); + Saturate<T> satValue(value); + + for (T i = 0; i < static_cast<T>(sNumOps); ++i) { + A(++value == ++satValue); + } +} + +template<typename T> +static void +TestPostfixIncr() +{ + T value = StartValue<T>(); + Saturate<T> satValue(value); + + for (T i = 0; i < static_cast<T>(sNumOps); ++i) { + A(value++ == satValue++); + } +} + +template<typename T> +static void +TestAdd() +{ + T value = StartValue<T>(); + Saturate<T> satValue(value); + + for (T i = 0; i < static_cast<T>(sNumOps); ++i) { + A((value + i) == (satValue + i)); + } +} + +// Subtract +// + +template<typename T> +static void +TestPrefixDecr() +{ + T value = StartValue<T>(); + Saturate<T> satValue(value); + + for (T i = 0; i < static_cast<T>(sNumOps); ++i) { + A(--value == --satValue); + } +} + +template<typename T> +static void +TestPostfixDecr() +{ + T value = StartValue<T>(); + Saturate<T> satValue(value); + + for (T i = 0; i < static_cast<T>(sNumOps); ++i) { + A(value-- == satValue--); + } +} + +template<typename T> +static void +TestSub() +{ + T value = StartValue<T>(); + Saturate<T> satValue(value); + + for (T i = 0; i < static_cast<T>(sNumOps); ++i) { + A((value - i) == (satValue - i)); + } +} + +// Corner cases near bounds +// + +template<typename T> +static void +TestUpperBound() +{ + Saturate<T> satValue(std::numeric_limits<T>::max()); + + A(--satValue == (std::numeric_limits<T>::max() - 1)); + A(++satValue == (std::numeric_limits<T>::max())); + A(++satValue == (std::numeric_limits<T>::max())); // don't overflow here + A(++satValue == (std::numeric_limits<T>::max())); // don't overflow here + A(--satValue == (std::numeric_limits<T>::max() - 1)); // back at (max - 1) + A(--satValue == (std::numeric_limits<T>::max() - 2)); +} + +template<typename T> +static void +TestLowerBound() +{ + Saturate<T> satValue(std::numeric_limits<T>::min()); + + A(++satValue == (std::numeric_limits<T>::min() + 1)); + A(--satValue == (std::numeric_limits<T>::min())); + A(--satValue == (std::numeric_limits<T>::min())); // don't overflow here + A(--satValue == (std::numeric_limits<T>::min())); // don't overflow here + A(++satValue == (std::numeric_limits<T>::min() + 1)); // back at (max + 1) + A(++satValue == (std::numeric_limits<T>::min() + 2)); +} + +// Framework +// + +template<typename T> +static void +TestAll() +{ + // Assert that we don't accidently hit type's range limits in tests. + const T value = StartValue<T>(); + A(std::numeric_limits<T>::min() + static_cast<T>(sNumOps) <= value); + A(std::numeric_limits<T>::max() - static_cast<T>(sNumOps) >= value); + + TestPrefixIncr<T>(); + TestPostfixIncr<T>(); + TestAdd<T>(); + + TestPrefixDecr<T>(); + TestPostfixDecr<T>(); + TestSub<T>(); + + TestUpperBound<T>(); + TestLowerBound<T>(); +} + +int +main() +{ + TestAll<int8_t>(); + TestAll<int16_t>(); + TestAll<int32_t>(); + TestAll<uint8_t>(); + TestAll<uint16_t>(); + TestAll<uint32_t>(); + return 0; +} diff --git a/mfbt/tests/TestScopeExit.cpp b/mfbt/tests/TestScopeExit.cpp new file mode 100644 index 000000000..fadd3a10a --- /dev/null +++ b/mfbt/tests/TestScopeExit.cpp @@ -0,0 +1,54 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/ScopeExit.h" + +using mozilla::MakeScopeExit; + +#define CHECK(c) \ + do { \ + bool cond = !!(c); \ + MOZ_RELEASE_ASSERT(cond, "Failed assertion: " #c); \ + if (!cond) { \ + return false; \ + } \ + } while (false) + +static bool +Test() +{ + int a = 1; + int b = 1; + + { + a++; + auto guardA = MakeScopeExit([&] { + a--; + }); + + b++; + auto guardB = MakeScopeExit([&] { + b--; + }); + + guardB.release(); + } + + CHECK(a == 1); + CHECK(b == 2); + + return true; +} + +int +main() +{ + if (!Test()) { + return 1; + } + return 0; +} diff --git a/mfbt/tests/TestSegmentedVector.cpp b/mfbt/tests/TestSegmentedVector.cpp new file mode 100644 index 000000000..2bf2540aa --- /dev/null +++ b/mfbt/tests/TestSegmentedVector.cpp @@ -0,0 +1,279 @@ +/* -*- Mode: C++; tab-width: 9; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +// This is included first to ensure it doesn't implicitly depend on anything +// else. +#include "mozilla/SegmentedVector.h" + +#include "mozilla/Alignment.h" +#include "mozilla/Assertions.h" + +using mozilla::SegmentedVector; + +// It would be nice if we could use the InfallibleAllocPolicy from mozalloc, +// but MFBT cannot use mozalloc. +class InfallibleAllocPolicy +{ +public: + template <typename T> + T* pod_malloc(size_t aNumElems) + { + if (aNumElems & mozilla::tl::MulOverflowMask<sizeof(T)>::value) { + MOZ_CRASH("TestSegmentedVector.cpp: overflow"); + } + T* rv = static_cast<T*>(malloc(aNumElems * sizeof(T))); + if (!rv) { + MOZ_CRASH("TestSegmentedVector.cpp: out of memory"); + } + return rv; + } + + void free_(void* aPtr) { free(aPtr); } +}; + +// We want to test Append(), which is fallible and marked with +// MOZ_MUST_USE. But we're using an infallible alloc policy, and so +// don't really need to check the result. Casting to |void| works with clang +// but not GCC, so we instead use this dummy variable which works with both +// compilers. +static int gDummy; + +// This tests basic segmented vector construction and iteration. +void TestBasics() +{ + // A SegmentedVector with a POD element type. + typedef SegmentedVector<int, 1024, InfallibleAllocPolicy> MyVector; + MyVector v; + int i, n; + + MOZ_RELEASE_ASSERT(v.IsEmpty()); + + // Add 100 elements, then check various things. + i = 0; + for ( ; i < 100; i++) { + gDummy = v.Append(mozilla::Move(i)); + } + MOZ_RELEASE_ASSERT(!v.IsEmpty()); + MOZ_RELEASE_ASSERT(v.Length() == 100); + + n = 0; + for (auto iter = v.Iter(); !iter.Done(); iter.Next()) { + MOZ_RELEASE_ASSERT(iter.Get() == n); + n++; + } + MOZ_RELEASE_ASSERT(n == 100); + + // Add another 900 elements, then re-check. + for ( ; i < 1000; i++) { + v.InfallibleAppend(mozilla::Move(i)); + } + MOZ_RELEASE_ASSERT(!v.IsEmpty()); + MOZ_RELEASE_ASSERT(v.Length() == 1000); + + n = 0; + for (auto iter = v.Iter(); !iter.Done(); iter.Next()) { + MOZ_RELEASE_ASSERT(iter.Get() == n); + n++; + } + MOZ_RELEASE_ASSERT(n == 1000); + + // Pop off all of the elements. + MOZ_RELEASE_ASSERT(v.Length() == 1000); + for (int len = (int)v.Length(); len > 0; len--) { + MOZ_RELEASE_ASSERT(v.GetLast() == len - 1); + v.PopLast(); + } + MOZ_RELEASE_ASSERT(v.IsEmpty()); + MOZ_RELEASE_ASSERT(v.Length() == 0); + + // Fill the vector up again to prepare for the clear. + for (i = 0; i < 1000; i++) { + v.InfallibleAppend(mozilla::Move(i)); + } + MOZ_RELEASE_ASSERT(!v.IsEmpty()); + MOZ_RELEASE_ASSERT(v.Length() == 1000); + + v.Clear(); + MOZ_RELEASE_ASSERT(v.IsEmpty()); + MOZ_RELEASE_ASSERT(v.Length() == 0); + + // Fill the vector up to verify PopLastN works. + for (i = 0; i < 1000; ++i) { + v.InfallibleAppend(mozilla::Move(i)); + } + MOZ_RELEASE_ASSERT(!v.IsEmpty()); + MOZ_RELEASE_ASSERT(v.Length() == 1000); + + // Verify we pop the right amount of elements. + v.PopLastN(300); + MOZ_RELEASE_ASSERT(v.Length() == 700); + + // Verify the contents are what we expect. + n = 0; + for (auto iter = v.Iter(); !iter.Done(); iter.Next()) { + MOZ_RELEASE_ASSERT(iter.Get() == n); + n++; + } + MOZ_RELEASE_ASSERT(n == 700); +} + +static size_t gNumDefaultCtors; +static size_t gNumExplicitCtors; +static size_t gNumCopyCtors; +static size_t gNumMoveCtors; +static size_t gNumDtors; + +struct NonPOD +{ + NonPOD() { gNumDefaultCtors++; } + explicit NonPOD(int x) { gNumExplicitCtors++; } + NonPOD(NonPOD&) { gNumCopyCtors++; } + NonPOD(NonPOD&&) { gNumMoveCtors++; } + ~NonPOD() { gNumDtors++; } +}; + +// This tests how segmented vectors with non-POD elements construct and +// destruct those elements. +void TestConstructorsAndDestructors() +{ + size_t defaultCtorCalls = 0; + size_t explicitCtorCalls = 0; + size_t copyCtorCalls = 0; + size_t moveCtorCalls = 0; + size_t dtorCalls = 0; + + { + static const size_t segmentSize = 64; + + // A SegmentedVector with a non-POD element type. + NonPOD x(1); // explicit constructor called + explicitCtorCalls++; + SegmentedVector<NonPOD, segmentSize, InfallibleAllocPolicy> v; + // default constructor called 0 times + MOZ_RELEASE_ASSERT(v.IsEmpty()); + gDummy = v.Append(x); // copy constructor called + copyCtorCalls++; + NonPOD y(1); // explicit constructor called + explicitCtorCalls++; + gDummy = v.Append(mozilla::Move(y)); // move constructor called + moveCtorCalls++; + NonPOD z(1); // explicit constructor called + explicitCtorCalls++; + v.InfallibleAppend(mozilla::Move(z)); // move constructor called + moveCtorCalls++; + v.PopLast(); // destructor called 1 time + dtorCalls++; + MOZ_RELEASE_ASSERT(gNumDtors == dtorCalls); + v.Clear(); // destructor called 2 times + dtorCalls += 2; + + // Test that PopLastN() correctly calls the destructors of all the + // elements in the segments it destroys. + // + // We depend on the size of NonPOD when determining how many things + // to push onto the vector. It would be nicer to get this information + // from SegmentedVector itself... + static_assert(sizeof(NonPOD) == 1, "Fix length calculations!"); + + size_t nonFullLastSegmentSize = segmentSize - 1; + for (size_t i = 0; i < nonFullLastSegmentSize; ++i) { + gDummy = v.Append(x); // copy constructor called + copyCtorCalls++; + } + MOZ_RELEASE_ASSERT(gNumCopyCtors == copyCtorCalls); + + // Pop some of the elements. + { + size_t partialPopAmount = 5; + MOZ_RELEASE_ASSERT(nonFullLastSegmentSize > partialPopAmount); + v.PopLastN(partialPopAmount); // destructor called partialPopAmount times + dtorCalls += partialPopAmount; + MOZ_RELEASE_ASSERT(v.Length() == nonFullLastSegmentSize - partialPopAmount); + MOZ_RELEASE_ASSERT(!v.IsEmpty()); + MOZ_RELEASE_ASSERT(gNumDtors == dtorCalls); + } + + // Pop a full segment. + { + size_t length = v.Length(); + v.PopLastN(length); + dtorCalls += length; + // These two tests *are* semantically different given the underlying + // implementation; Length sums up the sizes of the internal segments, + // while IsEmpty looks at the sequence of internal segments. + MOZ_RELEASE_ASSERT(v.Length() == 0); + MOZ_RELEASE_ASSERT(v.IsEmpty()); + MOZ_RELEASE_ASSERT(gNumDtors == dtorCalls); + } + + size_t multipleSegmentsSize = (segmentSize * 3) / 2; + for (size_t i = 0; i < multipleSegmentsSize; ++i) { + gDummy = v.Append(x); // copy constructor called + copyCtorCalls++; + } + MOZ_RELEASE_ASSERT(gNumCopyCtors == copyCtorCalls); + + // Pop across segment boundaries. + { + v.PopLastN(segmentSize); + dtorCalls += segmentSize; + MOZ_RELEASE_ASSERT(v.Length() == (multipleSegmentsSize - segmentSize)); + MOZ_RELEASE_ASSERT(!v.IsEmpty()); + MOZ_RELEASE_ASSERT(gNumDtors == dtorCalls); + } + + // Clear everything here to make calculations easier. + { + size_t length = v.Length(); + v.Clear(); + dtorCalls += length; + MOZ_RELEASE_ASSERT(v.IsEmpty()); + MOZ_RELEASE_ASSERT(gNumDtors == dtorCalls); + } + + MOZ_RELEASE_ASSERT(gNumDefaultCtors == defaultCtorCalls); + MOZ_RELEASE_ASSERT(gNumExplicitCtors == explicitCtorCalls); + MOZ_RELEASE_ASSERT(gNumCopyCtors == copyCtorCalls); + MOZ_RELEASE_ASSERT(gNumMoveCtors == moveCtorCalls); + MOZ_RELEASE_ASSERT(gNumDtors == dtorCalls); + } // destructor called for x, y, z + dtorCalls += 3; + MOZ_RELEASE_ASSERT(gNumDtors == dtorCalls); +} + +struct A { int mX; int mY; }; +struct B { int mX; char mY; double mZ; }; +struct C { A mA; B mB; }; +struct D { char mBuf[101]; }; +struct E { }; + +// This tests that we get the right segment capacities for specified segment +// sizes, and that the elements are aligned appropriately. +void TestSegmentCapacitiesAndAlignments() +{ + // When SegmentedVector's constructor is passed a size, it asserts that the + // vector's segment capacity results in a segment size equal to (or very + // close to) the passed size. + // + // Also, SegmentedVector has a static assertion that elements are + // appropriately aligned. + SegmentedVector<double, 512> v1(512); + SegmentedVector<A, 1024> v2(1024); + SegmentedVector<B, 999> v3(999); + SegmentedVector<C, 10> v4(10); + SegmentedVector<D, 1234> v5(1234); + SegmentedVector<E> v6(4096); // 4096 is the default segment size + SegmentedVector<mozilla::AlignedElem<16>, 100> v7(100); +} + +int main(void) +{ + TestBasics(); + TestConstructorsAndDestructors(); + TestSegmentCapacitiesAndAlignments(); + + return 0; +} diff --git a/mfbt/tests/TestSplayTree.cpp b/mfbt/tests/TestSplayTree.cpp new file mode 100644 index 000000000..030336fa7 --- /dev/null +++ b/mfbt/tests/TestSplayTree.cpp @@ -0,0 +1,212 @@ +/* -*- Mode: C++; tab-width: 9; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/ArrayUtils.h" +#include "mozilla/Assertions.h" +#include "mozilla/SplayTree.h" +#include "mozilla/Unused.h" + +using mozilla::SplayTree; +using mozilla::SplayTreeNode; + +// The following array contains the values 0..999 in random order, as computed +// with the following Python program: +// +// from random import shuffle +// x = range(1000) +// shuffle(x) +// print(x); +// +static int gValues[] = { + 778, 999, 248, 795, 607, 177, 725, 33, 215, 565, 436, 821, 941, 802, 322, 54, + 151, 416, 531, 65, 818, 99, 340, 401, 274, 767, 278, 617, 425, 629, 833, 878, + 440, 984, 724, 519, 100, 369, 490, 131, 422, 169, 932, 476, 823, 521, 390, + 781, 747, 218, 376, 461, 717, 532, 471, 298, 720, 608, 334, 788, 161, 500, + 280, 963, 430, 484, 779, 572, 96, 333, 650, 158, 199, 137, 991, 399, 882, + 689, 358, 548, 196, 718, 211, 388, 133, 188, 321, 892, 25, 694, 735, 886, + 872, 785, 195, 275, 696, 975, 393, 619, 894, 18, 281, 191, 792, 846, 861, + 351, 542, 806, 570, 702, 931, 585, 444, 284, 217, 132, 251, 253, 302, 808, + 224, 37, 63, 863, 409, 49, 780, 790, 31, 638, 890, 186, 114, 152, 949, 491, + 207, 392, 170, 460, 794, 482, 877, 407, 263, 909, 249, 710, 614, 51, 431, + 915, 62, 332, 74, 495, 901, 23, 365, 752, 89, 660, 745, 741, 547, 669, 449, + 465, 605, 107, 774, 205, 852, 266, 247, 690, 835, 765, 410, 140, 122, 400, + 510, 664, 105, 935, 230, 134, 106, 959, 375, 884, 361, 527, 715, 840, 272, + 232, 102, 415, 903, 117, 313, 153, 463, 464, 876, 406, 967, 713, 381, 836, + 555, 190, 859, 172, 483, 61, 633, 294, 993, 72, 337, 11, 896, 523, 101, 916, + 244, 566, 706, 533, 439, 201, 222, 695, 739, 553, 571, 289, 918, 209, 189, + 357, 814, 670, 866, 910, 579, 246, 636, 750, 891, 494, 758, 341, 626, 426, + 772, 254, 682, 588, 104, 347, 184, 977, 126, 498, 165, 955, 241, 516, 235, + 497, 121, 123, 791, 844, 259, 995, 283, 602, 417, 221, 308, 855, 429, 86, + 345, 928, 44, 679, 796, 363, 402, 445, 492, 450, 964, 749, 925, 847, 637, + 982, 648, 635, 481, 564, 867, 940, 291, 159, 290, 929, 59, 712, 986, 611, + 954, 820, 103, 622, 316, 142, 204, 225, 678, 314, 84, 578, 315, 141, 990, + 880, 504, 969, 412, 746, 47, 517, 124, 848, 466, 438, 674, 979, 782, 651, + 181, 26, 435, 832, 386, 951, 229, 642, 655, 91, 162, 921, 647, 113, 686, 56, + 805, 763, 245, 581, 287, 998, 525, 641, 135, 634, 237, 728, 112, 828, 228, + 899, 1, 723, 16, 613, 144, 659, 97, 185, 312, 292, 733, 624, 276, 387, 926, + 339, 768, 960, 610, 807, 656, 851, 219, 582, 709, 927, 514, 680, 870, 597, + 536, 77, 164, 512, 149, 900, 85, 335, 997, 8, 705, 777, 653, 815, 311, 701, + 507, 202, 530, 827, 541, 958, 82, 874, 55, 487, 383, 885, 684, 180, 829, 760, + 109, 194, 540, 816, 906, 657, 469, 446, 857, 907, 38, 600, 618, 797, 950, + 822, 277, 842, 116, 513, 255, 424, 643, 163, 372, 129, 67, 118, 754, 529, + 917, 687, 473, 174, 538, 939, 663, 775, 474, 242, 883, 20, 837, 293, 584, + 943, 32, 176, 904, 14, 448, 893, 888, 744, 171, 714, 454, 691, 261, 934, 606, + 789, 825, 671, 397, 338, 317, 612, 737, 130, 41, 923, 574, 136, 980, 850, 12, + 729, 197, 403, 57, 783, 360, 146, 75, 432, 447, 192, 799, 740, 267, 214, 250, + 367, 853, 968, 120, 736, 391, 881, 784, 665, 68, 398, 350, 839, 268, 697, + 567, 428, 738, 48, 182, 70, 220, 865, 418, 374, 148, 945, 353, 539, 589, 307, + 427, 506, 265, 558, 128, 46, 336, 299, 349, 309, 377, 304, 420, 30, 34, 875, + 948, 212, 394, 442, 719, 273, 269, 157, 502, 675, 751, 838, 897, 862, 831, + 676, 590, 811, 966, 854, 477, 15, 598, 573, 108, 98, 81, 408, 421, 296, 73, + 644, 456, 362, 666, 550, 331, 368, 193, 470, 203, 769, 342, 36, 604, 60, 970, + 748, 813, 522, 515, 90, 672, 243, 793, 947, 595, 632, 912, 475, 258, 80, 873, + 623, 524, 546, 262, 727, 216, 505, 330, 373, 58, 297, 609, 908, 150, 206, + 703, 755, 260, 511, 213, 198, 766, 898, 992, 488, 405, 974, 770, 936, 743, + 554, 0, 499, 976, 94, 160, 919, 434, 324, 156, 757, 830, 677, 183, 630, 871, + 640, 938, 518, 344, 366, 742, 552, 306, 535, 200, 652, 496, 233, 419, 787, + 318, 981, 371, 166, 143, 384, 88, 508, 698, 812, 559, 658, 549, 208, 599, + 621, 961, 668, 563, 93, 154, 587, 560, 389, 3, 210, 326, 4, 924, 300, 2, 804, + 914, 801, 753, 654, 27, 236, 19, 708, 451, 985, 596, 478, 922, 240, 127, 994, + 983, 385, 472, 40, 528, 288, 111, 543, 568, 155, 625, 759, 937, 956, 545, + 953, 962, 382, 479, 809, 557, 501, 354, 414, 343, 378, 843, 379, 178, 556, + 800, 803, 592, 627, 942, 576, 920, 704, 707, 726, 223, 119, 404, 24, 879, + 722, 868, 5, 238, 817, 520, 631, 946, 462, 457, 295, 480, 957, 441, 145, 286, + 303, 688, 17, 628, 493, 364, 226, 110, 615, 69, 320, 534, 593, 721, 411, 285, + 869, 952, 849, 139, 356, 346, 28, 887, 810, 92, 798, 544, 458, 996, 692, 396, + 667, 328, 173, 22, 773, 50, 645, 987, 42, 685, 734, 700, 683, 601, 580, 639, + 913, 323, 858, 179, 761, 6, 841, 905, 234, 730, 29, 21, 575, 586, 902, 443, + 826, 646, 257, 125, 649, 53, 453, 252, 13, 87, 971, 227, 485, 168, 380, 711, + 79, 732, 325, 52, 468, 76, 551, 39, 395, 327, 973, 459, 45, 583, 989, 147, + 455, 776, 944, 569, 889, 256, 35, 175, 834, 756, 933, 860, 526, 845, 864, + 764, 771, 282, 9, 693, 352, 731, 7, 577, 264, 319, 138, 467, 819, 930, 231, + 115, 988, 978, 762, 486, 301, 616, 10, 78, 603, 452, 965, 279, 972, 413, 895, + 591, 662, 594, 348, 423, 489, 43, 699, 433, 509, 355, 270, 66, 83, 95, 561, + 661, 562, 329, 620, 370, 64, 187, 503, 716, 856, 310, 786, 167, 71, 239, 359, + 537, 437, 305, 673, 824, 911, 681, 271 +}; + +struct SplayInt : SplayTreeNode<SplayInt> +{ + explicit SplayInt(int aValue) : mValue(aValue) {} + + static int compare(const SplayInt& aOne, const SplayInt& aTwo) + { + if (aOne.mValue < aTwo.mValue) { + return -1; + } + if (aOne.mValue > aTwo.mValue) { + return 1; + } + return 0; + } + + int mValue; +}; + +struct SplayNoCopy : SplayTreeNode<SplayNoCopy> +{ + SplayNoCopy(const SplayNoCopy&) = delete; + SplayNoCopy(SplayNoCopy&&) = delete; + + static int compare(const SplayNoCopy&, const SplayNoCopy&) { return 0; } +}; + +static SplayTree<SplayNoCopy, SplayNoCopy> testNoCopy; + +int +main() +{ + mozilla::Unused << testNoCopy; + + SplayTree<SplayInt, SplayInt> tree; + + MOZ_RELEASE_ASSERT(tree.empty()); + + MOZ_RELEASE_ASSERT(!tree.find(SplayInt(0))); + + static const int N = mozilla::ArrayLength(gValues); + + // Insert the values, and check each one is findable just after insertion. + for (int i = 0; i < N; i++) { + tree.insert(new SplayInt(gValues[i])); + SplayInt* inserted = tree.find(SplayInt(gValues[i])); + MOZ_RELEASE_ASSERT(inserted); + MOZ_RELEASE_ASSERT(tree.findOrInsert(SplayInt(gValues[i])) == inserted); + tree.checkCoherency(); + } + + // Check they're all findable after all insertions. + for (int i = 0; i < N; i++) { + MOZ_RELEASE_ASSERT(tree.find(SplayInt(gValues[i]))); + MOZ_RELEASE_ASSERT(tree.findOrInsert(SplayInt(gValues[i]))); + tree.checkCoherency(); + } + + // Check that non-inserted values cannot be found. + MOZ_RELEASE_ASSERT(!tree.find(SplayInt(-1))); + MOZ_RELEASE_ASSERT(!tree.find(SplayInt(N))); + MOZ_RELEASE_ASSERT(!tree.find(SplayInt(0x7fffffff))); + + // Remove the values, and check each one is not findable just after removal. + for (int i = 0; i < N; i++) { + SplayInt* removed = tree.remove(SplayInt(gValues[i])); + MOZ_RELEASE_ASSERT(removed->mValue == gValues[i]); + MOZ_RELEASE_ASSERT(!tree.find(*removed)); + delete removed; + tree.checkCoherency(); + } + + MOZ_RELEASE_ASSERT(tree.empty()); + + // Insert the values, and check each one is findable just after insertion. + for (int i = 0; i < N; i++) { + SplayInt* inserted = tree.findOrInsert(SplayInt(gValues[i])); + MOZ_RELEASE_ASSERT(tree.find(SplayInt(gValues[i])) == inserted); + MOZ_RELEASE_ASSERT(tree.findOrInsert(SplayInt(gValues[i])) == inserted); + tree.checkCoherency(); + } + + // Check they're all findable after all insertions. + for (int i = 0; i < N; i++) { + MOZ_RELEASE_ASSERT(tree.find(SplayInt(gValues[i]))); + MOZ_RELEASE_ASSERT(tree.findOrInsert(SplayInt(gValues[i]))); + tree.checkCoherency(); + } + + // Check that non-inserted values cannot be found. + MOZ_RELEASE_ASSERT(!tree.find(SplayInt(-1))); + MOZ_RELEASE_ASSERT(!tree.find(SplayInt(N))); + MOZ_RELEASE_ASSERT(!tree.find(SplayInt(0x7fffffff))); + + // Remove the values, and check each one is not findable just after removal. + for (int i = 0; i < N; i++) { + SplayInt* removed = tree.remove(SplayInt(gValues[i])); + MOZ_RELEASE_ASSERT(removed->mValue == gValues[i]); + MOZ_RELEASE_ASSERT(!tree.find(*removed)); + delete removed; + tree.checkCoherency(); + } + + MOZ_RELEASE_ASSERT(tree.empty()); + + // Reinsert the values, in reverse order to last time. + for (int i = 0; i < N; i++) { + tree.insert(new SplayInt(gValues[N - i - 1])); + tree.checkCoherency(); + } + + // Remove the minimum value repeatedly. + for (int i = 0; i < N; i++) { + SplayInt* removed = tree.removeMin(); + MOZ_RELEASE_ASSERT(removed->mValue == i); + delete removed; + tree.checkCoherency(); + } + + MOZ_RELEASE_ASSERT(tree.empty()); + + return 0; +} diff --git a/mfbt/tests/TestTemplateLib.cpp b/mfbt/tests/TestTemplateLib.cpp new file mode 100644 index 000000000..7ad0831ed --- /dev/null +++ b/mfbt/tests/TestTemplateLib.cpp @@ -0,0 +1,35 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/TemplateLib.h" + +using mozilla::tl::And; + +static_assert(And<>::value == true, + "And<>::value should be true"); +static_assert(And<true>::value == true, + "And<true>::value should be true"); +static_assert(And<false>::value == false, + "And<false>::value should be false"); +static_assert(And<false, true>::value == false, + "And<false, true>::value should be false"); +static_assert(And<false, false>::value == false, + "And<false, false>::value should be false"); +static_assert(And<true, false>::value == false, + "And<true, false>::value should be false"); +static_assert(And<true, true>::value == true, + "And<true, true>::value should be true"); +static_assert(And<true, true, true>::value == true, + "And<true, true, true>::value should be true"); +static_assert(And<true, false, true>::value == false, + "And<true, false, true>::value should be false"); + +int +main() +{ + // Nothing to do here. + return 0; +} diff --git a/mfbt/tests/TestTuple.cpp b/mfbt/tests/TestTuple.cpp new file mode 100644 index 000000000..a85552fef --- /dev/null +++ b/mfbt/tests/TestTuple.cpp @@ -0,0 +1,296 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ + /* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/Move.h" +#include "mozilla/Pair.h" +#include "mozilla/Tuple.h" +#include "mozilla/TypeTraits.h" +#include "mozilla/UniquePtr.h" +#include "mozilla/Unused.h" + +#include <stddef.h> +#include <utility> + +using mozilla::Get; +using mozilla::IsSame; +using mozilla::MakeTuple; +using mozilla::MakeUnique; +using mozilla::Move; +using mozilla::Pair; +using mozilla::Tie; +using mozilla::Tuple; +using mozilla::UniquePtr; +using mozilla::Unused; +using std::pair; + +#define CHECK(c) \ + do { \ + bool cond = !!(c); \ + MOZ_RELEASE_ASSERT(cond, "Failed assertion: " #c); \ + } while (false) + +// The second argument is the expected type. It's variadic to allow the +// type to contain commas. +#define CHECK_TYPE(expression, ...) \ + static_assert(IsSame<decltype(expression), __VA_ARGS__>::value, \ + "Type mismatch!") + +struct ConvertibleToInt +{ + operator int() const { return 42; } +}; + +static void +TestConstruction() +{ + // Default construction + Tuple<> a; + Unused << a; + Tuple<int> b; + Unused << b; + + // Construction from elements + int x = 1, y = 1; + Tuple<int, int> c{x, y}; + Tuple<int&, const int&> d{x, y}; + x = 42; + y = 42; + CHECK(Get<0>(c) == 1); + CHECK(Get<1>(c) == 1); + CHECK(Get<0>(d) == 42); + CHECK(Get<1>(d) == 42); + + // Construction from objects convertible to the element types + Tuple<int, int> e{1.0, ConvertibleToInt{}}; + + // Copy construction + Tuple<int> x1; + Tuple<int> x2{x1}; + + Tuple<int, int> f(c); + CHECK(Get<0>(f) == 1); + CHECK(Get<0>(f) == 1); + + // Move construction + Tuple<UniquePtr<int>> g{MakeUnique<int>(42)}; + Tuple<UniquePtr<int>> h{Move(g)}; + CHECK(Get<0>(g) == nullptr); + CHECK(*Get<0>(h) == 42); +} + +static void +TestConstructionFromMozPair() +{ + // Construction from elements + int x = 1, y = 1; + Pair<int, int> a{x, y}; + Pair<int&, const int&> b{x, y}; + Tuple<int, int> c(a); + Tuple<int&, const int&> d(b); + x = 42; + y = 42; + CHECK(Get<0>(c) == 1); + CHECK(Get<1>(c) == 1); + CHECK(Get<0>(d) == 42); + CHECK(Get<1>(d) == 42); +} + +static void +TestConstructionFromStdPair() +{ + // Construction from elements + int x = 1, y = 1; + pair<int, int> a{x, y}; + pair<int&, const int&> b{x, y}; + Tuple<int, int> c(a); + Tuple<int&, const int&> d(b); + x = 42; + y = 42; + CHECK(Get<0>(c) == 1); + CHECK(Get<1>(c) == 1); + CHECK(Get<0>(d) == 42); + CHECK(Get<1>(d) == 42); +} + +static void +TestAssignment() +{ + // Copy assignment + Tuple<int> a{0}; + Tuple<int> b{42}; + a = b; + CHECK(Get<0>(a) == 42); + + // Assignment to reference member + int i = 0; + int j = 42; + Tuple<int&> c{i}; + Tuple<int&> d{j}; + c = d; + CHECK(i == 42); + + // Move assignment + Tuple<UniquePtr<int>> e{MakeUnique<int>(0)}; + Tuple<UniquePtr<int>> f{MakeUnique<int>(42)}; + e = Move(f); + CHECK(*Get<0>(e) == 42); + CHECK(Get<0>(f) == nullptr); +} + +static void +TestAssignmentFromMozPair() +{ + // Copy assignment + Tuple<int, int> a{0, 0}; + Pair<int, int> b{42, 42}; + a = b; + CHECK(Get<0>(a) == 42); + CHECK(Get<1>(a) == 42); + + // Assignment to reference member + int i = 0; + int j = 0; + int k = 42; + Tuple<int&, int&> c{i, j}; + Pair<int&, int&> d{k, k}; + c = d; + CHECK(i == 42); + CHECK(j == 42); + + // Move assignment + Tuple<UniquePtr<int>, UniquePtr<int>> e{MakeUnique<int>(0), + MakeUnique<int>(0)}; + Pair<UniquePtr<int>, UniquePtr<int>> f{MakeUnique<int>(42), + MakeUnique<int>(42)}; + e = Move(f); + CHECK(*Get<0>(e) == 42); + CHECK(*Get<1>(e) == 42); + CHECK(f.first() == nullptr); + CHECK(f.second() == nullptr); +} + +static void +TestAssignmentFromStdPair() +{ + // Copy assignment + Tuple<int, int> a{0, 0}; + pair<int, int> b{42, 42}; + a = b; + CHECK(Get<0>(a) == 42); + CHECK(Get<1>(a) == 42); + + // Assignment to reference member + int i = 0; + int j = 0; + int k = 42; + Tuple<int&, int&> c{i, j}; + pair<int&, int&> d{k, k}; + c = d; + CHECK(i == 42); + CHECK(j == 42); + + // Move assignment. + Tuple<UniquePtr<int>, UniquePtr<int>> e{MakeUnique<int>(0), MakeUnique<int>(0)}; + // XXX: On some platforms std::pair doesn't support move constructor. + pair<UniquePtr<int>, UniquePtr<int>> f; + f.first = MakeUnique<int>(42); + f.second = MakeUnique<int>(42); + + e = Move(f); + CHECK(*Get<0>(e) == 42); + CHECK(*Get<1>(e) == 42); + CHECK(f.first == nullptr); + CHECK(f.second == nullptr); +} + +static void +TestGet() +{ + int x = 1; + int y = 2; + int z = 3; + Tuple<int, int&, const int&> tuple(x, y, z); + + // Using Get<>() to read elements + CHECK(Get<0>(tuple) == 1); + CHECK(Get<1>(tuple) == 2); + CHECK(Get<2>(tuple) == 3); + + // Using Get<>() to write to elements + Get<0>(tuple) = 41; + CHECK(Get<0>(tuple) == 41); + + // Writing through reference elements + Get<1>(tuple) = 42; + CHECK(Get<1>(tuple) == 42); + CHECK(y == 42); +} + +static void +TestMakeTuple() +{ + auto tuple = MakeTuple(42, 0.5f, 'c'); + CHECK_TYPE(tuple, Tuple<int, float, char>); + CHECK(Get<0>(tuple) == 42); + CHECK(Get<1>(tuple) == 0.5f); + CHECK(Get<2>(tuple) == 'c'); + + // Make sure we don't infer the type to be Tuple<int&>. + int x = 1; + auto tuple2 = MakeTuple(x); + CHECK_TYPE(tuple2, Tuple<int>); + x = 2; + CHECK(Get<0>(tuple2) == 1); +} + +static bool +TestTie() +{ + int i; + float f; + char c; + Tuple<int, float, char> rhs1(42, 0.5f, 'c'); + Tie(i, f, c) = rhs1; + CHECK(i == Get<0>(rhs1)); + CHECK(f == Get<1>(rhs1)); + CHECK(c == Get<2>(rhs1)); + // Test conversions + Tuple<ConvertibleToInt, double, unsigned char> rhs2(ConvertibleToInt(), + 0.7f, 'd'); + Tie(i, f, c) = rhs2; + CHECK(i == Get<0>(rhs2)); + CHECK(f == Get<1>(rhs2)); + CHECK(c == Get<2>(rhs2)); + + // Test Pair + Pair<int, float> rhs3(-1, 1.2f); + Tie(i, f) = rhs3; + CHECK(i == rhs3.first()); + CHECK(f == rhs3.second()); + + pair<int, float> rhs4(42, 1.5f); + Tie(i, f) = rhs4; + CHECK(i == rhs4.first); + CHECK(f == rhs4.second); + + return true; +} + +int +main() +{ + TestConstruction(); + TestConstructionFromMozPair(); + TestConstructionFromStdPair(); + TestAssignment(); + TestAssignmentFromMozPair(); + TestAssignmentFromStdPair(); + TestGet(); + TestMakeTuple(); + TestTie(); + return 0; +} diff --git a/mfbt/tests/TestTypeTraits.cpp b/mfbt/tests/TestTypeTraits.cpp new file mode 100644 index 000000000..f0a565142 --- /dev/null +++ b/mfbt/tests/TestTypeTraits.cpp @@ -0,0 +1,660 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/TypeTraits.h" + +#define TEST_CV_QUALIFIERS(test, type, ...) \ + test(type, __VA_ARGS__) \ + test(const type, __VA_ARGS__) \ + test(volatile type, __VA_ARGS__) \ + test(const volatile type, __VA_ARGS__) + +using mozilla::AddLvalueReference; +using mozilla::AddPointer; +using mozilla::AddRvalueReference; +using mozilla::Decay; +using mozilla::DeclVal; +using mozilla::IsFunction; +using mozilla::IsArray; +using mozilla::IsBaseOf; +using mozilla::IsClass; +using mozilla::IsConvertible; +using mozilla::IsEmpty; +using mozilla::IsLvalueReference; +using mozilla::IsPointer; +using mozilla::IsReference; +using mozilla::IsRvalueReference; +using mozilla::IsSame; +using mozilla::IsSigned; +using mozilla::IsUnsigned; +using mozilla::IsDestructible; +using mozilla::MakeSigned; +using mozilla::MakeUnsigned; +using mozilla::RemoveExtent; +using mozilla::RemovePointer; + +static_assert(!IsFunction<int>::value, + "int is not a function type"); +static_assert(IsFunction<void(int)>::value, + "void(int) is a function type"); +static_assert(!IsFunction<void(*)(int)>::value, + "void(*)(int) is not a function type"); + +static_assert(!IsArray<bool>::value, + "bool not an array"); +static_assert(IsArray<bool[]>::value, + "bool[] is an array"); +static_assert(IsArray<bool[5]>::value, + "bool[5] is an array"); + +static_assert(!IsPointer<bool>::value, + "bool not a pointer"); +static_assert(IsPointer<bool*>::value, + "bool* is a pointer"); +static_assert(IsPointer<bool* const>::value, + "bool* const is a pointer"); +static_assert(IsPointer<bool* volatile>::value, + "bool* volatile is a pointer"); +static_assert(IsPointer<bool* const volatile>::value, + "bool* const volatile is a pointer"); +static_assert(IsPointer<bool**>::value, + "bool** is a pointer"); +static_assert(IsPointer<void (*)(void)>::value, + "void (*)(void) is a pointer"); +struct IsPointerTest { bool m; void f(); }; +static_assert(!IsPointer<IsPointerTest>::value, + "IsPointerTest not a pointer"); +static_assert(IsPointer<IsPointerTest*>::value, + "IsPointerTest* is a pointer"); +static_assert(!IsPointer<bool(IsPointerTest::*)>::value, + "bool(IsPointerTest::*) not a pointer"); +static_assert(!IsPointer<void(IsPointerTest::*)(void)>::value, + "void(IsPointerTest::*)(void) not a pointer"); + +static_assert(!IsLvalueReference<bool>::value, + "bool not an lvalue reference"); +static_assert(!IsLvalueReference<bool*>::value, + "bool* not an lvalue reference"); +static_assert(IsLvalueReference<bool&>::value, + "bool& is an lvalue reference"); +static_assert(!IsLvalueReference<bool&&>::value, + "bool&& not an lvalue reference"); + +static_assert(!IsLvalueReference<void>::value, + "void not an lvalue reference"); +static_assert(!IsLvalueReference<void*>::value, + "void* not an lvalue reference"); + +static_assert(!IsLvalueReference<int>::value, + "int not an lvalue reference"); +static_assert(!IsLvalueReference<int*>::value, + "int* not an lvalue reference"); +static_assert(IsLvalueReference<int&>::value, + "int& is an lvalue reference"); +static_assert(!IsLvalueReference<int&&>::value, + "int&& not an lvalue reference"); + +static_assert(!IsRvalueReference<bool>::value, + "bool not an rvalue reference"); +static_assert(!IsRvalueReference<bool*>::value, + "bool* not an rvalue reference"); +static_assert(!IsRvalueReference<bool&>::value, + "bool& not an rvalue reference"); +static_assert(IsRvalueReference<bool&&>::value, + "bool&& is an rvalue reference"); + +static_assert(!IsRvalueReference<void>::value, + "void not an rvalue reference"); +static_assert(!IsRvalueReference<void*>::value, + "void* not an rvalue reference"); + +static_assert(!IsRvalueReference<int>::value, + "int not an rvalue reference"); +static_assert(!IsRvalueReference<int*>::value, + "int* not an rvalue reference"); +static_assert(!IsRvalueReference<int&>::value, + "int& not an rvalue reference"); +static_assert(IsRvalueReference<int&&>::value, + "int&& is an rvalue reference"); + +static_assert(!IsReference<bool>::value, + "bool not a reference"); +static_assert(!IsReference<bool*>::value, + "bool* not a reference"); +static_assert(IsReference<bool&>::value, + "bool& is a reference"); +static_assert(IsReference<bool&&>::value, + "bool&& is a reference"); + +static_assert(!IsReference<void>::value, + "void not a reference"); +static_assert(!IsReference<void*>::value, + "void* not a reference"); + +static_assert(!IsReference<int>::value, + "int not a reference"); +static_assert(!IsReference<int*>::value, + "int* not a reference"); +static_assert(IsReference<int&>::value, + "int& is a reference"); +static_assert(IsReference<int&&>::value, + "int&& is a reference"); + +namespace CPlusPlus11IsMemberPointer { + +using mozilla::IsMemberPointer; + +struct S {}; +union U {}; + +#define ASSERT_IS_MEMBER_POINTER(type, msg) \ + static_assert(IsMemberPointer<type>::value, #type msg); +#define TEST_IS_MEMBER_POINTER(type) \ + TEST_CV_QUALIFIERS(ASSERT_IS_MEMBER_POINTER, type, \ + " is a member pointer type") + +TEST_IS_MEMBER_POINTER(int S::*) +TEST_IS_MEMBER_POINTER(int U::*) + +#undef TEST_IS_MEMBER_POINTER +#undef ASSERT_IS_MEMBER_POINTER + +#define ASSERT_IS_NOT_MEMBER_POINTER(type, msg) \ + static_assert(!IsMemberPointer<type>::value, #type msg); +#define TEST_IS_NOT_MEMBER_POINTER(type) \ + TEST_CV_QUALIFIERS(ASSERT_IS_NOT_MEMBER_POINTER, type, \ + " is not a member pointer type") + +TEST_IS_NOT_MEMBER_POINTER(int*) + +#undef TEST_IS_NOT_MEMBER_POINTER +#undef ASSERT_IS_NOT_MEMBER_POINTER + +} // CPlusPlus11IsMemberPointer + +namespace CPlusPlus11IsScalar { + +using mozilla::IsScalar; + +enum E {}; +enum class EC {}; +class C {}; +struct S {}; +union U {}; + +#define ASSERT_IS_SCALAR(type, msg) \ + static_assert(IsScalar<type>::value, #type msg); +#define TEST_IS_SCALAR(type) \ + TEST_CV_QUALIFIERS(ASSERT_IS_SCALAR, type, " is a scalar type") + +TEST_IS_SCALAR(int) +TEST_IS_SCALAR(float) +TEST_IS_SCALAR(E) +TEST_IS_SCALAR(EC) +TEST_IS_SCALAR(S*) +TEST_IS_SCALAR(int S::*) + +#undef TEST_IS_SCALAR +#undef ASSERT_IS_SCALAR + +#define ASSERT_IS_NOT_SCALAR(type, msg) \ + static_assert(!IsScalar<type>::value, #type msg); +#define TEST_IS_NOT_SCALAR(type) \ + TEST_CV_QUALIFIERS(ASSERT_IS_NOT_SCALAR, type, " is not a scalar type") + +TEST_IS_NOT_SCALAR(C) +TEST_IS_NOT_SCALAR(S) +TEST_IS_NOT_SCALAR(U) + +#undef TEST_IS_NOT_SCALAR +#undef ASSERT_IS_NOT_SCALAR + +} // CPlusPlus11IsScalar + +struct S1 {}; +union U1 { int mX; }; + +static_assert(!IsClass<int>::value, + "int isn't a class"); +static_assert(IsClass<const S1>::value, + "S is a class"); +static_assert(!IsClass<U1>::value, + "U isn't a class"); + +static_assert(!mozilla::IsEmpty<int>::value, + "not a class => not empty"); +static_assert(!mozilla::IsEmpty<bool[5]>::value, + "not a class => not empty"); + +static_assert(!mozilla::IsEmpty<U1>::value, + "not a class => not empty"); + +struct E1 {}; +struct E2 { int : 0; }; +struct E3 : E1 {}; +struct E4 : E2 {}; + +static_assert(IsEmpty<const volatile S1>::value, + "S should be empty"); + +static_assert(mozilla::IsEmpty<E1>::value && + mozilla::IsEmpty<E2>::value && + mozilla::IsEmpty<E3>::value && + mozilla::IsEmpty<E4>::value, + "all empty"); + +union U2 { E1 e1; }; +static_assert(!mozilla::IsEmpty<U2>::value, + "not a class => not empty"); + +struct NE1 { int mX; }; +struct NE2 : virtual E1 {}; +struct NE3 : E2 { virtual ~NE3() {} }; +struct NE4 { virtual void f() {} }; + +static_assert(!mozilla::IsEmpty<NE1>::value && + !mozilla::IsEmpty<NE2>::value && + !mozilla::IsEmpty<NE3>::value && + !mozilla::IsEmpty<NE4>::value, + "all empty"); + +static_assert(!IsSigned<bool>::value, + "bool shouldn't be signed"); +static_assert(IsUnsigned<bool>::value, + "bool should be unsigned"); + +static_assert(!IsSigned<const bool>::value, + "const bool shouldn't be signed"); +static_assert(IsUnsigned<const bool>::value, + "const bool should be unsigned"); + +static_assert(!IsSigned<volatile bool>::value, + "volatile bool shouldn't be signed"); +static_assert(IsUnsigned<volatile bool>::value, + "volatile bool should be unsigned"); + +static_assert(!IsSigned<unsigned char>::value, + "unsigned char shouldn't be signed"); +static_assert(IsUnsigned<unsigned char>::value, + "unsigned char should be unsigned"); +static_assert(IsSigned<signed char>::value, + "signed char should be signed"); +static_assert(!IsUnsigned<signed char>::value, + "signed char shouldn't be unsigned"); + +static_assert(!IsSigned<unsigned short>::value, + "unsigned short shouldn't be signed"); +static_assert(IsUnsigned<unsigned short>::value, + "unsigned short should be unsigned"); +static_assert(IsSigned<short>::value, + "short should be signed"); +static_assert(!IsUnsigned<short>::value, + "short shouldn't be unsigned"); + +static_assert(!IsSigned<unsigned int>::value, + "unsigned int shouldn't be signed"); +static_assert(IsUnsigned<unsigned int>::value, + "unsigned int should be unsigned"); +static_assert(IsSigned<int>::value, + "int should be signed"); +static_assert(!IsUnsigned<int>::value, + "int shouldn't be unsigned"); + +static_assert(!IsSigned<unsigned long>::value, + "unsigned long shouldn't be signed"); +static_assert(IsUnsigned<unsigned long>::value, + "unsigned long should be unsigned"); +static_assert(IsSigned<long>::value, + "long should be signed"); +static_assert(!IsUnsigned<long>::value, + "long shouldn't be unsigned"); + +static_assert(IsSigned<float>::value, + "float should be signed"); +static_assert(!IsUnsigned<float>::value, + "float shouldn't be unsigned"); + +static_assert(IsSigned<const float>::value, + "const float should be signed"); +static_assert(!IsUnsigned<const float>::value, + "const float shouldn't be unsigned"); + +static_assert(IsSigned<double>::value, + "double should be signed"); +static_assert(!IsUnsigned<double>::value, + "double shouldn't be unsigned"); + +static_assert(IsSigned<volatile double>::value, + "volatile double should be signed"); +static_assert(!IsUnsigned<volatile double>::value, + "volatile double shouldn't be unsigned"); + +static_assert(IsSigned<long double>::value, + "long double should be signed"); +static_assert(!IsUnsigned<long double>::value, + "long double shouldn't be unsigned"); + +static_assert(IsSigned<const volatile long double>::value, + "const volatile long double should be signed"); +static_assert(!IsUnsigned<const volatile long double>::value, + "const volatile long double shouldn't be unsigned"); + +class NotIntConstructible +{ + NotIntConstructible(int) = delete; +}; + +static_assert(!IsSigned<NotIntConstructible>::value, + "non-arithmetic types are not signed"); +static_assert(!IsUnsigned<NotIntConstructible>::value, + "non-arithmetic types are not unsigned"); + +class PublicDestructible +{ +public: + ~PublicDestructible(); +}; +class PrivateDestructible +{ +private: + ~PrivateDestructible(); +}; +class TrivialDestructible +{ +}; + +static_assert(IsDestructible<PublicDestructible>::value, + "public destructible class is destructible"); +static_assert(!IsDestructible<PrivateDestructible>::value, + "private destructible class is not destructible"); +static_assert(IsDestructible<TrivialDestructible>::value, + "trivial destructible class is destructible"); + +namespace CPlusPlus11IsBaseOf { + +// Adapted from C++11 § 20.9.6. +struct B {}; +struct B1 : B {}; +struct B2 : B {}; +struct D : private B1, private B2 {}; + +static void +StandardIsBaseOfTests() +{ + static_assert((IsBaseOf<B, D>::value) == true, + "IsBaseOf fails on diamond"); + static_assert((IsBaseOf<const B, D>::value) == true, + "IsBaseOf fails on diamond plus constness change"); + static_assert((IsBaseOf<B, const D>::value) == true, + "IsBaseOf fails on diamond plus constness change"); + static_assert((IsBaseOf<B, const B>::value) == true, + "IsBaseOf fails on constness change"); + static_assert((IsBaseOf<D, B>::value) == false, + "IsBaseOf got the direction of inheritance wrong"); + static_assert((IsBaseOf<B&, D&>::value) == false, + "IsBaseOf should return false on references"); + static_assert((IsBaseOf<B[3], D[3]>::value) == false, + "IsBaseOf should return false on arrays"); + // We fail at the following test. To fix it, we need to specialize IsBaseOf + // for all built-in types. + // static_assert((IsBaseOf<int, int>::value) == false); +} + +} /* namespace CPlusPlus11IsBaseOf */ + +class A { }; +class B : public A { }; +class C : private A { }; +class D { }; +class E : public A { }; +class F : public B, public E { }; + +static void +TestIsBaseOf() +{ + static_assert((IsBaseOf<A, B>::value), + "A is a base of B"); + static_assert((!IsBaseOf<B, A>::value), + "B is not a base of A"); + static_assert((IsBaseOf<A, C>::value), + "A is a base of C"); + static_assert((!IsBaseOf<C, A>::value), + "C is not a base of A"); + static_assert((IsBaseOf<A, F>::value), + "A is a base of F"); + static_assert((!IsBaseOf<F, A>::value), + "F is not a base of A"); + static_assert((!IsBaseOf<A, D>::value), + "A is not a base of D"); + static_assert((!IsBaseOf<D, A>::value), + "D is not a base of A"); + static_assert((IsBaseOf<B, B>::value), + "B is the same as B (and therefore, a base of B)"); +} + +class ExplicitCopyConstructor { + explicit ExplicitCopyConstructor(const ExplicitCopyConstructor&) = default; +}; + +static void +TestIsConvertible() +{ + // Pointer type convertibility + static_assert((IsConvertible<A*, A*>::value), + "A* should convert to A*"); + static_assert((IsConvertible<B*, A*>::value), + "B* should convert to A*"); + static_assert((!IsConvertible<A*, B*>::value), + "A* shouldn't convert to B*"); + static_assert((!IsConvertible<A*, C*>::value), + "A* shouldn't convert to C*"); + static_assert((!IsConvertible<A*, D*>::value), + "A* shouldn't convert to unrelated D*"); + static_assert((!IsConvertible<D*, A*>::value), + "D* shouldn't convert to unrelated A*"); + + // Instance type convertibility + static_assert((IsConvertible<A, A>::value), + "A is A"); + static_assert((IsConvertible<B, A>::value), + "B converts to A"); + static_assert((!IsConvertible<D, A>::value), + "D and A are unrelated"); + static_assert((!IsConvertible<A, D>::value), + "A and D are unrelated"); + + static_assert(IsConvertible<void, void>::value, "void is void"); + static_assert(!IsConvertible<A, void>::value, "A shouldn't convert to void"); + static_assert(!IsConvertible<void, B>::value, "void shouldn't convert to B"); + + static_assert(!IsConvertible<const ExplicitCopyConstructor&, + ExplicitCopyConstructor>::value, + "IsConvertible should test for implicit convertibility"); + + // These cases seem to require C++11 support to properly implement them, so + // for now just disable them. + //static_assert((!IsConvertible<C*, A*>::value), + // "C* shouldn't convert to A* (private inheritance)"); + //static_assert((!IsConvertible<C, A>::value), + // "C doesn't convert to A (private inheritance)"); +} + +static_assert(IsSame<AddLvalueReference<int>::Type, int&>::value, + "not adding & to int correctly"); +static_assert(IsSame<AddLvalueReference<volatile int&>::Type, volatile int&>::value, + "not adding & to volatile int& correctly"); +static_assert(IsSame<AddLvalueReference<void*>::Type, void*&>::value, + "not adding & to void* correctly"); +static_assert(IsSame<AddLvalueReference<void>::Type, void>::value, + "void shouldn't be transformed by AddLvalueReference"); +static_assert(IsSame<AddLvalueReference<struct S1&&>::Type, struct S1&>::value, + "not reference-collapsing struct S1&& & to struct S1& correctly"); + +static_assert(IsSame<AddRvalueReference<int>::Type, int&&>::value, + "not adding && to int correctly"); +static_assert(IsSame<AddRvalueReference<volatile int&>::Type, volatile int&>::value, + "not adding && to volatile int& correctly"); +static_assert(IsSame<AddRvalueReference<const int&&>::Type, const int&&>::value, + "not adding && to volatile int& correctly"); +static_assert(IsSame<AddRvalueReference<void*>::Type, void*&&>::value, + "not adding && to void* correctly"); +static_assert(IsSame<AddRvalueReference<void>::Type, void>::value, + "void shouldn't be transformed by AddRvalueReference"); +static_assert(IsSame<AddRvalueReference<struct S1&>::Type, struct S1&>::value, + "not reference-collapsing struct S1& && to struct S1& correctly"); + +struct TestWithDefaultConstructor +{ + int foo() const { return 0; } +}; +struct TestWithNoDefaultConstructor +{ + explicit TestWithNoDefaultConstructor(int) {} + int foo() const { return 1; } +}; + +static_assert(IsSame<decltype(TestWithDefaultConstructor().foo()), int>::value, + "decltype should work using a struct with a default constructor"); +static_assert(IsSame<decltype(DeclVal<TestWithDefaultConstructor>().foo()), int>::value, + "decltype should work using a DeclVal'd struct with a default constructor"); +static_assert(IsSame<decltype(DeclVal<TestWithNoDefaultConstructor>().foo()), int>::value, + "decltype should work using a DeclVal'd struct without a default constructor"); + +static_assert(IsSame<MakeSigned<const unsigned char>::Type, const signed char>::value, + "const unsigned char won't signify correctly"); +static_assert(IsSame<MakeSigned<volatile unsigned short>::Type, volatile signed short>::value, + "volatile unsigned short won't signify correctly"); +static_assert(IsSame<MakeSigned<const volatile unsigned int>::Type, const volatile signed int>::value, + "const volatile unsigned int won't signify correctly"); +static_assert(IsSame<MakeSigned<unsigned long>::Type, signed long>::value, + "unsigned long won't signify correctly"); +static_assert(IsSame<MakeSigned<const signed char>::Type, const signed char>::value, + "const signed char won't signify correctly"); + +static_assert(IsSame<MakeSigned<volatile signed short>::Type, volatile signed short>::value, + "volatile signed short won't signify correctly"); +static_assert(IsSame<MakeSigned<const volatile signed int>::Type, const volatile signed int>::value, + "const volatile signed int won't signify correctly"); +static_assert(IsSame<MakeSigned<signed long>::Type, signed long>::value, + "signed long won't signify correctly"); + +static_assert(IsSame<MakeSigned<char>::Type, signed char>::value, + "char won't signify correctly"); +static_assert(IsSame<MakeSigned<volatile char>::Type, volatile signed char>::value, + "volatile char won't signify correctly"); +static_assert(IsSame<MakeSigned<const char>::Type, const signed char>::value, + "const char won't signify correctly"); + +static_assert(IsSame<MakeUnsigned<const signed char>::Type, const unsigned char>::value, + "const signed char won't unsignify correctly"); +static_assert(IsSame<MakeUnsigned<volatile signed short>::Type, volatile unsigned short>::value, + "volatile signed short won't unsignify correctly"); +static_assert(IsSame<MakeUnsigned<const volatile signed int>::Type, const volatile unsigned int>::value, + "const volatile signed int won't unsignify correctly"); +static_assert(IsSame<MakeUnsigned<signed long>::Type, unsigned long>::value, + "signed long won't unsignify correctly"); + +static_assert(IsSame<MakeUnsigned<const unsigned char>::Type, const unsigned char>::value, + "const unsigned char won't unsignify correctly"); + +static_assert(IsSame<MakeUnsigned<volatile unsigned short>::Type, volatile unsigned short>::value, + "volatile unsigned short won't unsignify correctly"); +static_assert(IsSame<MakeUnsigned<const volatile unsigned int>::Type, const volatile unsigned int>::value, + "const volatile unsigned int won't unsignify correctly"); +static_assert(IsSame<MakeUnsigned<unsigned long>::Type, unsigned long>::value, + "signed long won't unsignify correctly"); + +static_assert(IsSame<MakeUnsigned<char>::Type, unsigned char>::value, + "char won't unsignify correctly"); +static_assert(IsSame<MakeUnsigned<volatile char>::Type, volatile unsigned char>::value, + "volatile char won't unsignify correctly"); +static_assert(IsSame<MakeUnsigned<const char>::Type, const unsigned char>::value, + "const char won't unsignify correctly"); + +static_assert(IsSame<RemoveExtent<int>::Type, int>::value, + "removing extent from non-array must return the non-array"); +static_assert(IsSame<RemoveExtent<const int[]>::Type, const int>::value, + "removing extent from unknown-bound array must return element type"); +static_assert(IsSame<RemoveExtent<volatile int[5]>::Type, volatile int>::value, + "removing extent from known-bound array must return element type"); +static_assert(IsSame<RemoveExtent<long[][17]>::Type, long[17]>::value, + "removing extent from multidimensional array must return element type"); + +struct TestRemovePointer { bool m; void f(); }; +static_assert(IsSame<RemovePointer<int>::Type, int>::value, + "removing pointer from int must return int"); +static_assert(IsSame<RemovePointer<int*>::Type, int>::value, + "removing pointer from int* must return int"); +static_assert(IsSame<RemovePointer<int* const>::Type, int>::value, + "removing pointer from int* const must return int"); +static_assert(IsSame<RemovePointer<int* volatile>::Type, int>::value, + "removing pointer from int* volatile must return int"); +static_assert(IsSame<RemovePointer<const long*>::Type, const long>::value, + "removing pointer from const long* must return const long"); +static_assert(IsSame<RemovePointer<void* const>::Type, void>::value, + "removing pointer from void* const must return void"); +static_assert(IsSame<RemovePointer<void (TestRemovePointer::*)()>::Type, + void (TestRemovePointer::*)()>::value, + "removing pointer from void (S::*)() must return void (S::*)()"); +static_assert(IsSame<RemovePointer<void (*)()>::Type, void()>::value, + "removing pointer from void (*)() must return void()"); +static_assert(IsSame<RemovePointer<bool TestRemovePointer::*>::Type, + bool TestRemovePointer::*>::value, + "removing pointer from bool S::* must return bool S::*"); + +static_assert(IsSame<AddPointer<int>::Type, int*>::value, + "adding pointer to int must return int*"); +static_assert(IsSame<AddPointer<int*>::Type, int**>::value, + "adding pointer to int* must return int**"); +static_assert(IsSame<AddPointer<int&>::Type, int*>::value, + "adding pointer to int& must return int*"); +static_assert(IsSame<AddPointer<int* const>::Type, int* const*>::value, + "adding pointer to int* const must return int* const*"); +static_assert(IsSame<AddPointer<int* volatile>::Type, int* volatile*>::value, + "adding pointer to int* volatile must return int* volatile*"); + +static_assert(IsSame<Decay<int>::Type, int>::value, + "decaying int must return int"); +static_assert(IsSame<Decay<int*>::Type, int*>::value, + "decaying int* must return int*"); +static_assert(IsSame<Decay<int* const>::Type, int*>::value, + "decaying int* const must return int*"); +static_assert(IsSame<Decay<int* volatile>::Type, int*>::value, + "decaying int* volatile must return int*"); +static_assert(IsSame<Decay<int&>::Type, int>::value, + "decaying int& must return int"); +static_assert(IsSame<Decay<const int&>::Type, int>::value, + "decaying const int& must return int"); +static_assert(IsSame<Decay<int&&>::Type, int>::value, + "decaying int&& must return int"); +static_assert(IsSame<Decay<int[1]>::Type, int*>::value, + "decaying int[1] must return int*"); +static_assert(IsSame<Decay<void(int)>::Type, void(*)(int)>::value, + "decaying void(int) must return void(*)(int)"); + +/* + * Android's broken [u]intptr_t inttype macros are broken because its PRI*PTR + * macros are defined as "ld", but sizeof(long) is 8 and sizeof(intptr_t) + * is 4 on 32-bit Android. We redefine Android's PRI*PTR macros in + * IntegerPrintfMacros.h and assert here that our new definitions match the + * actual type sizes seen at compile time. + */ +#if defined(ANDROID) && !defined(__LP64__) +static_assert(mozilla::IsSame<int, intptr_t>::value, + "emulated PRI[di]PTR definitions will be wrong"); +static_assert(mozilla::IsSame<unsigned int, uintptr_t>::value, + "emulated PRI[ouxX]PTR definitions will be wrong"); +#endif + +int +main() +{ + CPlusPlus11IsBaseOf::StandardIsBaseOfTests(); + TestIsBaseOf(); + TestIsConvertible(); + return 0; +} diff --git a/mfbt/tests/TestTypedEnum.cpp b/mfbt/tests/TestTypedEnum.cpp new file mode 100644 index 000000000..43c36f2b8 --- /dev/null +++ b/mfbt/tests/TestTypedEnum.cpp @@ -0,0 +1,556 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/Attributes.h" +#include "mozilla/TypedEnumBits.h" + +#include <stdint.h> + +// A rough feature check for is_literal_type. Not very carefully checked. +// Feel free to amend as needed. +// We leave ANDROID out because it's using stlport which doesn't have std::is_literal_type. +#if __cplusplus >= 201103L && !defined(ANDROID) +# if defined(__clang__) + /* + * Per Clang documentation, "Note that marketing version numbers should not + * be used to check for language features, as different vendors use different + * numbering schemes. Instead, use the feature checking macros." + */ +# ifndef __has_extension +# define __has_extension __has_feature /* compatibility, for older versions of clang */ +# endif +# if __has_extension(is_literal) && __has_include(<type_traits>) +# define MOZ_HAVE_IS_LITERAL +# endif +# elif defined(__GNUC__) || defined(_MSC_VER) +# define MOZ_HAVE_IS_LITERAL +# endif +#endif + +#if defined(MOZ_HAVE_IS_LITERAL) && defined(MOZ_HAVE_CXX11_CONSTEXPR) +#include <type_traits> +template<typename T> +void +RequireLiteralType() +{ + static_assert(std::is_literal_type<T>::value, "Expected a literal type"); +} +#else // not MOZ_HAVE_IS_LITERAL +template<typename T> +void +RequireLiteralType() +{ +} +#endif + +template<typename T> +void +RequireLiteralType(const T&) +{ + RequireLiteralType<T>(); +} + +enum class AutoEnum { + A, + B = -3, + C +}; + +enum class CharEnum : char { + A, + B = 3, + C +}; + +enum class AutoEnumBitField { + A = 0x10, + B = 0x20, + C +}; + +enum class CharEnumBitField : char { + A = 0x10, + B, + C = 0x40 +}; + +struct Nested +{ + enum class AutoEnum { + A, + B, + C = -1 + }; + + enum class CharEnum : char { + A = 4, + B, + C = 1 + }; + + enum class AutoEnumBitField { + A, + B = 0x20, + C + }; + + enum class CharEnumBitField : char { + A = 1, + B = 1, + C = 1 + }; +}; + +MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(AutoEnumBitField) +MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(CharEnumBitField) +MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(Nested::AutoEnumBitField) +MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(Nested::CharEnumBitField) + +#define MAKE_STANDARD_BITFIELD_FOR_TYPE(IntType) \ + enum class BitFieldFor_##IntType : IntType { \ + A = 1, \ + B = 2, \ + C = 4, \ + }; \ + MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(BitFieldFor_##IntType) + +MAKE_STANDARD_BITFIELD_FOR_TYPE(int8_t) +MAKE_STANDARD_BITFIELD_FOR_TYPE(uint8_t) +MAKE_STANDARD_BITFIELD_FOR_TYPE(int16_t) +MAKE_STANDARD_BITFIELD_FOR_TYPE(uint16_t) +MAKE_STANDARD_BITFIELD_FOR_TYPE(int32_t) +MAKE_STANDARD_BITFIELD_FOR_TYPE(uint32_t) +MAKE_STANDARD_BITFIELD_FOR_TYPE(int64_t) +MAKE_STANDARD_BITFIELD_FOR_TYPE(uint64_t) +MAKE_STANDARD_BITFIELD_FOR_TYPE(char) +typedef signed char signed_char; +MAKE_STANDARD_BITFIELD_FOR_TYPE(signed_char) +typedef unsigned char unsigned_char; +MAKE_STANDARD_BITFIELD_FOR_TYPE(unsigned_char) +MAKE_STANDARD_BITFIELD_FOR_TYPE(short) +typedef unsigned short unsigned_short; +MAKE_STANDARD_BITFIELD_FOR_TYPE(unsigned_short) +MAKE_STANDARD_BITFIELD_FOR_TYPE(int) +typedef unsigned int unsigned_int; +MAKE_STANDARD_BITFIELD_FOR_TYPE(unsigned_int) +MAKE_STANDARD_BITFIELD_FOR_TYPE(long) +typedef unsigned long unsigned_long; +MAKE_STANDARD_BITFIELD_FOR_TYPE(unsigned_long) +typedef long long long_long; +MAKE_STANDARD_BITFIELD_FOR_TYPE(long_long) +typedef unsigned long long unsigned_long_long; +MAKE_STANDARD_BITFIELD_FOR_TYPE(unsigned_long_long) + +#undef MAKE_STANDARD_BITFIELD_FOR_TYPE + +template<typename T> +void +TestNonConvertibilityForOneType() +{ + using mozilla::IsConvertible; + + static_assert(!IsConvertible<T, bool>::value, "should not be convertible"); + static_assert(!IsConvertible<T, int>::value, "should not be convertible"); + static_assert(!IsConvertible<T, uint64_t>::value, "should not be convertible"); + + static_assert(!IsConvertible<bool, T>::value, "should not be convertible"); + static_assert(!IsConvertible<int, T>::value, "should not be convertible"); + static_assert(!IsConvertible<uint64_t, T>::value, "should not be convertible"); +} + +template<typename TypedEnum> +void +TestTypedEnumBasics() +{ + const TypedEnum a = TypedEnum::A; + int unused = int(a); + (void) unused; + RequireLiteralType(TypedEnum::A); + RequireLiteralType(a); + TestNonConvertibilityForOneType<TypedEnum>(); +} + +// Op wraps a bitwise binary operator, passed as a char template parameter, +// and applies it to its arguments (aT1, aT2). For example, +// +// Op<'|'>(aT1, aT2) +// +// is the same as +// +// aT1 | aT2. +// +template<char o, typename T1, typename T2> +auto Op(const T1& aT1, const T2& aT2) + -> decltype(aT1 | aT2) // See the static_assert's below --- the return type + // depends solely on the operands type, not on the + // choice of operation. +{ + using mozilla::IsSame; + static_assert(IsSame<decltype(aT1 | aT2), decltype(aT1 & aT2)>::value, + "binary ops should have the same result type"); + static_assert(IsSame<decltype(aT1 | aT2), decltype(aT1 ^ aT2)>::value, + "binary ops should have the same result type"); + + static_assert(o == '|' || + o == '&' || + o == '^', "unexpected operator character"); + + return o == '|' ? aT1 | aT2 + : o == '&' ? aT1 & aT2 + : aT1 ^ aT2; +} + +// OpAssign wraps a bitwise binary operator, passed as a char template +// parameter, and applies the corresponding compound-assignment operator to its +// arguments (aT1, aT2). For example, +// +// OpAssign<'|'>(aT1, aT2) +// +// is the same as +// +// aT1 |= aT2. +// +template<char o, typename T1, typename T2> +T1& OpAssign(T1& aT1, const T2& aT2) +{ + static_assert(o == '|' || + o == '&' || + o == '^', "unexpected operator character"); + + switch (o) { + case '|': return aT1 |= aT2; + case '&': return aT1 &= aT2; + case '^': return aT1 ^= aT2; + default: MOZ_CRASH(); + } +} + +// Tests a single binary bitwise operator, using a single set of three operands. +// The operations tested are: +// +// result = aT1 Op aT2; +// result Op= aT3; +// +// Where Op is the operator specified by the char template parameter 'o' and +// can be any of '|', '&', '^'. +// +// Note that the operands aT1, aT2, aT3 are intentionally passed with free +// types (separate template parameters for each) because their type may +// actually be different from TypedEnum: +// +// 1) Their type could be CastableTypedEnumResult<TypedEnum> if they are +// the result of a bitwise operation themselves; +// 2) In the non-c++11 legacy path, the type of enum values is also +// different from TypedEnum. +// +template<typename TypedEnum, char o, typename T1, typename T2, typename T3> +void TestBinOp(const T1& aT1, const T2& aT2, const T3& aT3) +{ + typedef typename mozilla::detail::UnsignedIntegerTypeForEnum<TypedEnum>::Type + UnsignedIntegerType; + + // Part 1: + // Test the bitwise binary operator i.e. + // result = aT1 Op aT2; + auto result = Op<o>(aT1, aT2); + + typedef decltype(result) ResultType; + + RequireLiteralType<ResultType>(); + TestNonConvertibilityForOneType<ResultType>(); + + UnsignedIntegerType unsignedIntegerResult = + Op<o>(UnsignedIntegerType(aT1), UnsignedIntegerType(aT2)); + + MOZ_RELEASE_ASSERT(unsignedIntegerResult == UnsignedIntegerType(result)); + MOZ_RELEASE_ASSERT(TypedEnum(unsignedIntegerResult) == TypedEnum(result)); + MOZ_RELEASE_ASSERT((!unsignedIntegerResult) == (!result)); + MOZ_RELEASE_ASSERT((!!unsignedIntegerResult) == (!!result)); + MOZ_RELEASE_ASSERT(bool(unsignedIntegerResult) == bool(result)); + + // Part 2: + // Test the compound-assignment operator, i.e. + // result Op= aT3; + TypedEnum newResult = result; + OpAssign<o>(newResult, aT3); + UnsignedIntegerType unsignedIntegerNewResult = unsignedIntegerResult; + OpAssign<o>(unsignedIntegerNewResult, UnsignedIntegerType(aT3)); + MOZ_RELEASE_ASSERT(TypedEnum(unsignedIntegerNewResult) == newResult); + + // Part 3: + // Test additional boolean operators that we unfortunately had to add to + // CastableTypedEnumResult at some point to please some compiler, + // even though bool convertibility should have been enough. + MOZ_RELEASE_ASSERT(result == TypedEnum(result)); + MOZ_RELEASE_ASSERT(!(result != TypedEnum(result))); + MOZ_RELEASE_ASSERT((result && true) == bool(result)); + MOZ_RELEASE_ASSERT((result && false) == false); + MOZ_RELEASE_ASSERT((true && result) == bool(result)); + MOZ_RELEASE_ASSERT((false && result && false) == false); + MOZ_RELEASE_ASSERT((result || false) == bool(result)); + MOZ_RELEASE_ASSERT((result || true) == true); + MOZ_RELEASE_ASSERT((false || result) == bool(result)); + MOZ_RELEASE_ASSERT((true || result) == true); +} + +// Similar to TestBinOp but testing the unary ~ operator. +template<typename TypedEnum, typename T> +void TestTilde(const T& aT) +{ + typedef typename mozilla::detail::UnsignedIntegerTypeForEnum<TypedEnum>::Type + UnsignedIntegerType; + + auto result = ~aT; + + typedef decltype(result) ResultType; + + RequireLiteralType<ResultType>(); + TestNonConvertibilityForOneType<ResultType>(); + + UnsignedIntegerType unsignedIntegerResult = ~(UnsignedIntegerType(aT)); + + MOZ_RELEASE_ASSERT(unsignedIntegerResult == UnsignedIntegerType(result)); + MOZ_RELEASE_ASSERT(TypedEnum(unsignedIntegerResult) == TypedEnum(result)); + MOZ_RELEASE_ASSERT((!unsignedIntegerResult) == (!result)); + MOZ_RELEASE_ASSERT((!!unsignedIntegerResult) == (!!result)); + MOZ_RELEASE_ASSERT(bool(unsignedIntegerResult) == bool(result)); +} + +// Helper dispatching a given triple of operands to all operator-specific +// testing functions. +template<typename TypedEnum, typename T1, typename T2, typename T3> +void TestAllOpsForGivenOperands(const T1& aT1, const T2& aT2, const T3& aT3) +{ + TestBinOp<TypedEnum, '|'>(aT1, aT2, aT3); + TestBinOp<TypedEnum, '&'>(aT1, aT2, aT3); + TestBinOp<TypedEnum, '^'>(aT1, aT2, aT3); + TestTilde<TypedEnum>(aT1); +} + +// Helper building various triples of operands using a given operator, +// and testing all operators with them. +template<typename TypedEnum, char o> +void TestAllOpsForOperandsBuiltUsingGivenOp() +{ + // The type of enum values like TypedEnum::A may be different from + // TypedEnum. That is the case in the legacy non-C++11 path. We want to + // ensure good test coverage even when these two types are distinct. + // To that effect, we have both 'auto' typed variables, preserving the + // original type of enum values, and 'plain' typed variables, that + // are plain TypedEnum's. + + const TypedEnum a_plain = TypedEnum::A; + const TypedEnum b_plain = TypedEnum::B; + const TypedEnum c_plain = TypedEnum::C; + + auto a_auto = TypedEnum::A; + auto b_auto = TypedEnum::B; + auto c_auto = TypedEnum::C; + + auto ab_plain = Op<o>(a_plain, b_plain); + auto bc_plain = Op<o>(b_plain, c_plain); + auto ab_auto = Op<o>(a_auto, b_auto); + auto bc_auto = Op<o>(b_auto, c_auto); + + // On each row below, we pass a triple of operands. Keep in mind that this + // is going to be received as (aT1, aT2, aT3) and the actual tests performed + // will be of the form + // + // result = aT1 Op aT2; + // result Op= aT3; + // + // For this reason, we carefully ensure that the values of (aT1, aT2) + // systematically cover all types of such pairs; to limit complexity, + // we are not so careful with aT3, and we just try to pass aT3's + // that may lead to nontrivial bitwise operations. + TestAllOpsForGivenOperands<TypedEnum>(a_plain, b_plain, c_plain); + TestAllOpsForGivenOperands<TypedEnum>(a_plain, bc_plain, b_auto); + TestAllOpsForGivenOperands<TypedEnum>(ab_plain, c_plain, a_plain); + TestAllOpsForGivenOperands<TypedEnum>(ab_plain, bc_plain, a_auto); + + TestAllOpsForGivenOperands<TypedEnum>(a_plain, b_auto, c_plain); + TestAllOpsForGivenOperands<TypedEnum>(a_plain, bc_auto, b_auto); + TestAllOpsForGivenOperands<TypedEnum>(ab_plain, c_auto, a_plain); + TestAllOpsForGivenOperands<TypedEnum>(ab_plain, bc_auto, a_auto); + + TestAllOpsForGivenOperands<TypedEnum>(a_auto, b_plain, c_plain); + TestAllOpsForGivenOperands<TypedEnum>(a_auto, bc_plain, b_auto); + TestAllOpsForGivenOperands<TypedEnum>(ab_auto, c_plain, a_plain); + TestAllOpsForGivenOperands<TypedEnum>(ab_auto, bc_plain, a_auto); + + TestAllOpsForGivenOperands<TypedEnum>(a_auto, b_auto, c_plain); + TestAllOpsForGivenOperands<TypedEnum>(a_auto, bc_auto, b_auto); + TestAllOpsForGivenOperands<TypedEnum>(ab_auto, c_auto, a_plain); + TestAllOpsForGivenOperands<TypedEnum>(ab_auto, bc_auto, a_auto); +} + +// Tests all bitwise operations on a given TypedEnum bitfield. +template<typename TypedEnum> +void +TestTypedEnumBitField() +{ + TestTypedEnumBasics<TypedEnum>(); + + TestAllOpsForOperandsBuiltUsingGivenOp<TypedEnum, '|'>(); + TestAllOpsForOperandsBuiltUsingGivenOp<TypedEnum, '&'>(); + TestAllOpsForOperandsBuiltUsingGivenOp<TypedEnum, '^'>(); +} + +// Checks that enum bitwise expressions have the same non-convertibility +// properties as c++11 enum classes do, i.e. not implicitly convertible to +// anything (though *explicitly* convertible). +void TestNoConversionsBetweenUnrelatedTypes() +{ + using mozilla::IsConvertible; + + // Two typed enum classes having the same underlying integer type, to ensure + // that we would catch bugs accidentally allowing conversions in that case. + typedef CharEnumBitField T1; + typedef Nested::CharEnumBitField T2; + + static_assert(!IsConvertible<T1, T2>::value, + "should not be convertible"); + static_assert(!IsConvertible<T1, decltype(T2::A)>::value, + "should not be convertible"); + static_assert(!IsConvertible<T1, decltype(T2::A | T2::B)>::value, + "should not be convertible"); + + static_assert(!IsConvertible<decltype(T1::A), T2>::value, + "should not be convertible"); + static_assert(!IsConvertible<decltype(T1::A), decltype(T2::A)>::value, + "should not be convertible"); + static_assert(!IsConvertible<decltype(T1::A), decltype(T2::A | T2::B)>::value, + "should not be convertible"); + + static_assert(!IsConvertible<decltype(T1::A | T1::B), T2>::value, + "should not be convertible"); + static_assert(!IsConvertible<decltype(T1::A | T1::B), decltype(T2::A)>::value, + "should not be convertible"); + static_assert(!IsConvertible<decltype(T1::A | T1::B), decltype(T2::A | T2::B)>::value, + "should not be convertible"); +} + +enum class Int8EnumWithHighBits : int8_t { + A = 0x20, + B = 0x40 +}; +MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(Int8EnumWithHighBits) + +enum class Uint8EnumWithHighBits : uint8_t { + A = 0x40, + B = 0x80 +}; +MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(Uint8EnumWithHighBits) + +enum class Int16EnumWithHighBits : int16_t { + A = 0x2000, + B = 0x4000 +}; +MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(Int16EnumWithHighBits) + +enum class Uint16EnumWithHighBits : uint16_t { + A = 0x4000, + B = 0x8000 +}; +MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(Uint16EnumWithHighBits) + +enum class Int32EnumWithHighBits : int32_t { + A = 0x20000000, + B = 0x40000000 +}; +MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(Int32EnumWithHighBits) + +enum class Uint32EnumWithHighBits : uint32_t { + A = 0x40000000u, + B = 0x80000000u +}; +MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(Uint32EnumWithHighBits) + +enum class Int64EnumWithHighBits : int64_t { + A = 0x2000000000000000ll, + B = 0x4000000000000000ll +}; +MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(Int64EnumWithHighBits) + +enum class Uint64EnumWithHighBits : uint64_t { + A = 0x4000000000000000ull, + B = 0x8000000000000000ull +}; +MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(Uint64EnumWithHighBits) + +// Checks that we don't accidentally truncate high bits by coercing to the wrong +// integer type internally when implementing bitwise ops. +template<typename EnumType, typename IntType> +void TestIsNotTruncated() +{ + EnumType a = EnumType::A; + EnumType b = EnumType::B; + MOZ_RELEASE_ASSERT(IntType(a)); + MOZ_RELEASE_ASSERT(IntType(b)); + MOZ_RELEASE_ASSERT(a | EnumType::B); + MOZ_RELEASE_ASSERT(a | b); + MOZ_RELEASE_ASSERT(EnumType::A | EnumType::B); + EnumType c = EnumType::A | EnumType::B; + MOZ_RELEASE_ASSERT(IntType(c)); + MOZ_RELEASE_ASSERT(c & c); + MOZ_RELEASE_ASSERT(c | c); + MOZ_RELEASE_ASSERT(c == (EnumType::A | EnumType::B)); + MOZ_RELEASE_ASSERT(a != (EnumType::A | EnumType::B)); + MOZ_RELEASE_ASSERT(b != (EnumType::A | EnumType::B)); + MOZ_RELEASE_ASSERT(c & EnumType::A); + MOZ_RELEASE_ASSERT(c & EnumType::B); + EnumType d = EnumType::A; + d |= EnumType::B; + MOZ_RELEASE_ASSERT(d == c); +} + +int +main() +{ + TestTypedEnumBasics<AutoEnum>(); + TestTypedEnumBasics<CharEnum>(); + TestTypedEnumBasics<Nested::AutoEnum>(); + TestTypedEnumBasics<Nested::CharEnum>(); + + TestTypedEnumBitField<AutoEnumBitField>(); + TestTypedEnumBitField<CharEnumBitField>(); + TestTypedEnumBitField<Nested::AutoEnumBitField>(); + TestTypedEnumBitField<Nested::CharEnumBitField>(); + + TestTypedEnumBitField<BitFieldFor_uint8_t>(); + TestTypedEnumBitField<BitFieldFor_int8_t>(); + TestTypedEnumBitField<BitFieldFor_uint16_t>(); + TestTypedEnumBitField<BitFieldFor_int16_t>(); + TestTypedEnumBitField<BitFieldFor_uint32_t>(); + TestTypedEnumBitField<BitFieldFor_int32_t>(); + TestTypedEnumBitField<BitFieldFor_uint64_t>(); + TestTypedEnumBitField<BitFieldFor_int64_t>(); + TestTypedEnumBitField<BitFieldFor_char>(); + TestTypedEnumBitField<BitFieldFor_signed_char>(); + TestTypedEnumBitField<BitFieldFor_unsigned_char>(); + TestTypedEnumBitField<BitFieldFor_short>(); + TestTypedEnumBitField<BitFieldFor_unsigned_short>(); + TestTypedEnumBitField<BitFieldFor_int>(); + TestTypedEnumBitField<BitFieldFor_unsigned_int>(); + TestTypedEnumBitField<BitFieldFor_long>(); + TestTypedEnumBitField<BitFieldFor_unsigned_long>(); + TestTypedEnumBitField<BitFieldFor_long_long>(); + TestTypedEnumBitField<BitFieldFor_unsigned_long_long>(); + + TestNoConversionsBetweenUnrelatedTypes(); + + TestIsNotTruncated<Int8EnumWithHighBits, int8_t>(); + TestIsNotTruncated<Int16EnumWithHighBits, int16_t>(); + TestIsNotTruncated<Int32EnumWithHighBits, int32_t>(); + TestIsNotTruncated<Int64EnumWithHighBits, int64_t>(); + TestIsNotTruncated<Uint8EnumWithHighBits, uint8_t>(); + TestIsNotTruncated<Uint16EnumWithHighBits, uint16_t>(); + TestIsNotTruncated<Uint32EnumWithHighBits, uint32_t>(); + TestIsNotTruncated<Uint64EnumWithHighBits, uint64_t>(); + + return 0; +} diff --git a/mfbt/tests/TestUniquePtr.cpp b/mfbt/tests/TestUniquePtr.cpp new file mode 100644 index 000000000..c866fcc3a --- /dev/null +++ b/mfbt/tests/TestUniquePtr.cpp @@ -0,0 +1,592 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Assertions.h" +#include "mozilla/Compiler.h" +#include "mozilla/Move.h" +#include "mozilla/TypeTraits.h" +#include "mozilla/UniquePtr.h" +#include "mozilla/Vector.h" + +#include <stddef.h> + +using mozilla::DefaultDelete; +using mozilla::IsSame; +using mozilla::MakeUnique; +using mozilla::Swap; +using mozilla::UniquePtr; +using mozilla::Vector; + +#define CHECK(c) \ + do { \ + bool cond = !!(c); \ + MOZ_ASSERT(cond, "Failed assertion: " #c); \ + if (!cond) { \ + return false; \ + } \ + } while (false) + +typedef UniquePtr<int> NewInt; +static_assert(sizeof(NewInt) == sizeof(int*), "stored most efficiently"); + +static size_t gADestructorCalls = 0; + +struct A +{ +public: + A() : mX(0) {} + virtual ~A() { gADestructorCalls++; } + + int mX; +}; + +static size_t gBDestructorCalls = 0; + +struct B : public A +{ +public: + B() : mY(1) {} + ~B() { gBDestructorCalls++; } + + int mY; +}; + +typedef UniquePtr<A> UniqueA; +typedef UniquePtr<B, UniqueA::DeleterType> UniqueB; // permit interconversion + +static_assert(sizeof(UniqueA) == sizeof(A*), "stored most efficiently"); +static_assert(sizeof(UniqueB) == sizeof(B*), "stored most efficiently"); + +struct DeleterSubclass : UniqueA::DeleterType {}; + +typedef UniquePtr<B, DeleterSubclass> UniqueC; +static_assert(sizeof(UniqueC) == sizeof(B*), "stored most efficiently"); + +static UniqueA +ReturnUniqueA() +{ + return UniqueA(new B); +} + +static UniqueA +ReturnLocalA() +{ + UniqueA a(new A); + return Move(a); +} + +static void +TestDeleterType() +{ + // Make sure UniquePtr will use its deleter's pointer type if it defines one. + typedef int* Ptr; + struct Deleter { + typedef Ptr pointer; + Deleter() {} + void operator()(int*p) { + delete p; + } + }; + UniquePtr<Ptr, Deleter> u(new int, Deleter()); +} + +static bool +TestDefaultFreeGuts() +{ + static_assert(IsSame<NewInt::DeleterType, DefaultDelete<int> >::value, + "weird deleter?"); + + NewInt n1(new int); + CHECK(n1); + CHECK(n1.get() != nullptr); + + n1 = nullptr; + CHECK(!n1); + CHECK(n1.get() == nullptr); + + int* p1 = new int; + n1.reset(p1); + CHECK(n1); + NewInt n2(Move(n1)); + CHECK(!n1); + CHECK(n1.get() == nullptr); + CHECK(n2.get() == p1); + + Swap(n1, n2); + CHECK(n1.get() == p1); + CHECK(n2.get() == nullptr); + + n1.swap(n2); + CHECK(n1.get() == nullptr); + CHECK(n2.get() == p1); + delete n2.release(); + + CHECK(n1.get() == nullptr); + CHECK(n2 == nullptr); + CHECK(nullptr == n2); + + int* p2 = new int; + int* p3 = new int; + n1.reset(p2); + n2.reset(p3); + CHECK(n1.get() == p2); + CHECK(n2.get() == p3); + + n1.swap(n2); + CHECK(n2 != nullptr); + CHECK(nullptr != n2); + CHECK(n2.get() == p2); + CHECK(n1.get() == p3); + + UniqueA a1; + CHECK(a1 == nullptr); + a1.reset(new A); + CHECK(gADestructorCalls == 0); + CHECK(a1->mX == 0); + + B* bp1 = new B; + bp1->mX = 5; + CHECK(gBDestructorCalls == 0); + a1.reset(bp1); + CHECK(gADestructorCalls == 1); + CHECK(a1->mX == 5); + a1.reset(nullptr); + CHECK(gADestructorCalls == 2); + CHECK(gBDestructorCalls == 1); + + B* bp2 = new B; + UniqueB b1(bp2); + UniqueA a2(nullptr); + a2 = Move(b1); + CHECK(gADestructorCalls == 2); + CHECK(gBDestructorCalls == 1); + + UniqueA a3(Move(a2)); + a3 = nullptr; + CHECK(gADestructorCalls == 3); + CHECK(gBDestructorCalls == 2); + + B* bp3 = new B; + bp3->mX = 42; + UniqueB b2(bp3); + UniqueA a4(Move(b2)); + CHECK(b2.get() == nullptr); + CHECK((*a4).mX == 42); + CHECK(gADestructorCalls == 3); + CHECK(gBDestructorCalls == 2); + + UniqueA a5(new A); + UniqueB b3(new B); + a5 = Move(b3); + CHECK(gADestructorCalls == 4); + CHECK(gBDestructorCalls == 2); + + ReturnUniqueA(); + CHECK(gADestructorCalls == 5); + CHECK(gBDestructorCalls == 3); + + ReturnLocalA(); + CHECK(gADestructorCalls == 6); + CHECK(gBDestructorCalls == 3); + + UniqueA a6(ReturnLocalA()); + a6 = nullptr; + CHECK(gADestructorCalls == 7); + CHECK(gBDestructorCalls == 3); + + UniqueC c1(new B); + UniqueA a7(new B); + a7 = Move(c1); + CHECK(gADestructorCalls == 8); + CHECK(gBDestructorCalls == 4); + + c1.reset(new B); + + UniqueA a8(Move(c1)); + CHECK(gADestructorCalls == 8); + CHECK(gBDestructorCalls == 4); + + // These smart pointers still own B resources. + CHECK(a4); + CHECK(a5); + CHECK(a7); + CHECK(a8); + return true; +} + +static bool +TestDefaultFree() +{ + CHECK(TestDefaultFreeGuts()); + CHECK(gADestructorCalls == 12); + CHECK(gBDestructorCalls == 8); + return true; +} + +static size_t FreeClassCounter = 0; + +struct FreeClass +{ +public: + FreeClass() {} + + void operator()(int* aPtr) + { + FreeClassCounter++; + delete aPtr; + } +}; + +typedef UniquePtr<int, FreeClass> NewIntCustom; +static_assert(sizeof(NewIntCustom) == sizeof(int*), + "stored most efficiently"); + +static bool +TestFreeClass() +{ + CHECK(FreeClassCounter == 0); + { + NewIntCustom n1(new int); + CHECK(FreeClassCounter == 0); + } + CHECK(FreeClassCounter == 1); + + NewIntCustom n2; + { + NewIntCustom n3(new int); + CHECK(FreeClassCounter == 1); + n2 = Move(n3); + } + CHECK(FreeClassCounter == 1); + n2 = nullptr; + CHECK(FreeClassCounter == 2); + + n2.reset(nullptr); + CHECK(FreeClassCounter == 2); + n2.reset(new int); + n2.reset(); + CHECK(FreeClassCounter == 3); + + NewIntCustom n4(new int, FreeClass()); + CHECK(FreeClassCounter == 3); + n4.reset(new int); + CHECK(FreeClassCounter == 4); + n4.reset(); + CHECK(FreeClassCounter == 5); + + FreeClass f; + NewIntCustom n5(new int, f); + CHECK(FreeClassCounter == 5); + int* p = n5.release(); + CHECK(FreeClassCounter == 5); + delete p; + + return true; +} + +typedef UniquePtr<int, DefaultDelete<int>&> IntDeleterRef; +typedef UniquePtr<A, DefaultDelete<A>&> ADeleterRef; +typedef UniquePtr<B, DefaultDelete<A>&> BDeleterRef; + +static_assert(sizeof(IntDeleterRef) > sizeof(int*), + "has to be heavier than an int* to store the reference"); +static_assert(sizeof(ADeleterRef) > sizeof(A*), + "has to be heavier than an A* to store the reference"); +static_assert(sizeof(BDeleterRef) > sizeof(int*), + "has to be heavier than a B* to store the reference"); + +static bool +TestReferenceDeleterGuts() +{ + DefaultDelete<int> delInt; + IntDeleterRef id1(new int, delInt); + + IntDeleterRef id2(Move(id1)); + CHECK(id1 == nullptr); + CHECK(nullptr != id2); + CHECK(&id1.get_deleter() == &id2.get_deleter()); + + IntDeleterRef id3(Move(id2)); + + DefaultDelete<A> delA; + ADeleterRef a1(new A, delA); + a1.reset(nullptr); + a1.reset(new B); + a1 = nullptr; + + BDeleterRef b1(new B, delA); + a1 = Move(b1); + + BDeleterRef b2(new B, delA); + + ADeleterRef a2(Move(b2)); + + return true; +} + +static bool +TestReferenceDeleter() +{ + gADestructorCalls = 0; + gBDestructorCalls = 0; + + CHECK(TestReferenceDeleterGuts()); + + CHECK(gADestructorCalls == 4); + CHECK(gBDestructorCalls == 3); + + gADestructorCalls = 0; + gBDestructorCalls = 0; + return true; +} + +typedef void (&FreeSignature)(void*); + +static size_t DeleteIntFunctionCallCount = 0; + +static void +DeleteIntFunction(void* aPtr) +{ + DeleteIntFunctionCallCount++; + delete static_cast<int*>(aPtr); +} + +static void +SetMallocedInt(UniquePtr<int, FreeSignature>& aPtr, int aI) +{ + int* newPtr = static_cast<int*>(malloc(sizeof(int))); + *newPtr = aI; + aPtr.reset(newPtr); +} + +static UniquePtr<int, FreeSignature> +MallocedInt(int aI) +{ + UniquePtr<int, FreeSignature> + ptr(static_cast<int*>(malloc(sizeof(int))), free); + *ptr = aI; + return Move(ptr); +} +static bool +TestFunctionReferenceDeleter() +{ + // Look for allocator mismatches and leaks to verify these bits + UniquePtr<int, FreeSignature> i1(MallocedInt(17)); + CHECK(*i1 == 17); + + SetMallocedInt(i1, 42); + CHECK(*i1 == 42); + + // These bits use a custom deleter so we can instrument deletion. + { + UniquePtr<int, FreeSignature> i2 = + UniquePtr<int, FreeSignature>(new int(42), DeleteIntFunction); + CHECK(DeleteIntFunctionCallCount == 0); + + i2.reset(new int(76)); + CHECK(DeleteIntFunctionCallCount == 1); + } + + CHECK(DeleteIntFunctionCallCount == 2); + + return true; +} + +template<typename T> +struct AppendNullptrTwice +{ + AppendNullptrTwice() {} + + bool operator()(Vector<T>& vec) + { + CHECK(vec.append(nullptr)); + CHECK(vec.append(nullptr)); + return true; + } +}; + +static size_t AAfter; +static size_t BAfter; + +static bool +TestVectorGuts() +{ + Vector<UniqueA> vec; + CHECK(vec.append(new B)); + CHECK(vec.append(new A)); + CHECK(AppendNullptrTwice<UniqueA>()(vec)); + CHECK(vec.append(new B)); + + size_t initialLength = vec.length(); + + UniqueA* begin = vec.begin(); + bool appendA = true; + do { + CHECK(appendA ? vec.append(new A) : vec.append(new B)); + appendA = !appendA; + } while (begin == vec.begin()); + + size_t numAppended = vec.length() - initialLength; + + BAfter = numAppended / 2; + AAfter = numAppended - numAppended / 2; + + CHECK(gADestructorCalls == 0); + CHECK(gBDestructorCalls == 0); + return true; +} + +static bool +TestVector() +{ + gADestructorCalls = 0; + gBDestructorCalls = 0; + + CHECK(TestVectorGuts()); + + CHECK(gADestructorCalls == 3 + AAfter + BAfter); + CHECK(gBDestructorCalls == 2 + BAfter); + return true; +} + +typedef UniquePtr<int[]> IntArray; +static_assert(sizeof(IntArray) == sizeof(int*), + "stored most efficiently"); + +static bool +TestArray() +{ + static_assert(IsSame<IntArray::DeleterType, DefaultDelete<int[]> >::value, + "weird deleter?"); + + IntArray n1(new int[5]); + CHECK(n1); + CHECK(n1.get() != nullptr); + + n1 = nullptr; + CHECK(!n1); + CHECK(n1.get() == nullptr); + + int* p1 = new int[42]; + n1.reset(p1); + CHECK(n1); + IntArray n2(Move(n1)); + CHECK(!n1); + CHECK(n1.get() == nullptr); + CHECK(n2.get() == p1); + + Swap(n1, n2); + CHECK(n1.get() == p1); + CHECK(n2.get() == nullptr); + + n1.swap(n2); + CHECK(n1.get() == nullptr); + CHECK(n2.get() == p1); + delete[] n2.release(); + + CHECK(n1.get() == nullptr); + CHECK(n2.get() == nullptr); + + int* p2 = new int[7]; + int* p3 = new int[42]; + n1.reset(p2); + n2.reset(p3); + CHECK(n1.get() == p2); + CHECK(n2.get() == p3); + + n1.swap(n2); + CHECK(n2.get() == p2); + CHECK(n1.get() == p3); + + n1 = Move(n2); + CHECK(n1.get() == p2); + n1 = Move(n2); + CHECK(n1.get() == nullptr); + + UniquePtr<A[]> a1(new A[17]); + static_assert(sizeof(a1) == sizeof(A*), + "stored most efficiently"); + + UniquePtr<A[]> a2(new A[5], DefaultDelete<A[]>()); + a2.reset(nullptr); + a2.reset(new A[17]); + a2 = nullptr; + + UniquePtr<A[]> a3(nullptr); + a3.reset(new A[7]); + + return true; +} + +struct Q +{ + Q() {} + Q(const Q&) {} + + Q(Q&, char) {} + + template<typename T> + Q(Q, T&&, int) {} + + Q(int, long, double, void*) {} +}; + +static int randomInt() { return 4; } + +static bool +TestMakeUnique() +{ + UniquePtr<int> a1(MakeUnique<int>()); + UniquePtr<long> a2(MakeUnique<long>(4)); + + // no args, easy + UniquePtr<Q> q0(MakeUnique<Q>()); + + // temporary bound to const lval ref + UniquePtr<Q> q1(MakeUnique<Q>(Q())); + + // passing through a non-const lval ref + UniquePtr<Q> q2(MakeUnique<Q>(*q1, 'c')); + + // pass by copying, forward a temporary, pass by value + UniquePtr<Q> q3(MakeUnique<Q>(Q(), UniquePtr<int>(), randomInt())); + + // various type mismatching to test "fuzzy" forwarding + UniquePtr<Q> q4(MakeUnique<Q>('s', 66LL, 3.141592654, &q3)); + + UniquePtr<char[]> c1(MakeUnique<char[]>(5)); + + return true; +} + +int +main() +{ + TestDeleterType(); + + if (!TestDefaultFree()) { + return 1; + } + if (!TestFreeClass()) { + return 1; + } + if (!TestReferenceDeleter()) { + return 1; + } + if (!TestFunctionReferenceDeleter()) { + return 1; + } + if (!TestVector()) { + return 1; + } + if (!TestArray()) { + return 1; + } + if (!TestMakeUnique()) { + return 1; + } + return 0; +} diff --git a/mfbt/tests/TestVariant.cpp b/mfbt/tests/TestVariant.cpp new file mode 100644 index 000000000..d47df70cb --- /dev/null +++ b/mfbt/tests/TestVariant.cpp @@ -0,0 +1,188 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/UniquePtr.h" +#include "mozilla/Variant.h" + +using mozilla::MakeUnique; +using mozilla::UniquePtr; +using mozilla::Variant; + +struct Destroyer { + static int destroyedCount; + ~Destroyer() { + destroyedCount++; + } +}; + +int Destroyer::destroyedCount = 0; + +static void +testSimple() +{ + printf("testSimple\n"); + Variant<uint32_t, uint64_t> v(uint64_t(1)); + MOZ_RELEASE_ASSERT(v.is<uint64_t>()); + MOZ_RELEASE_ASSERT(!v.is<uint32_t>()); + MOZ_RELEASE_ASSERT(v.as<uint64_t>() == 1); +} + +static void +testCopy() +{ + printf("testCopy\n"); + Variant<uint32_t, uint64_t> v1(uint64_t(1)); + Variant<uint32_t, uint64_t> v2(v1); + MOZ_RELEASE_ASSERT(v2.is<uint64_t>()); + MOZ_RELEASE_ASSERT(!v2.is<uint32_t>()); + MOZ_RELEASE_ASSERT(v2.as<uint64_t>() == 1); + + Variant<uint32_t, uint64_t> v3(uint32_t(10)); + v3 = v2; + MOZ_RELEASE_ASSERT(v3.is<uint64_t>()); + MOZ_RELEASE_ASSERT(v3.as<uint64_t>() == 1); +} + +static void +testMove() +{ + printf("testMove\n"); + Variant<UniquePtr<int>, char> v1(MakeUnique<int>(5)); + Variant<UniquePtr<int>, char> v2(Move(v1)); + + MOZ_RELEASE_ASSERT(v2.is<UniquePtr<int>>()); + MOZ_RELEASE_ASSERT(*v2.as<UniquePtr<int>>() == 5); + + MOZ_RELEASE_ASSERT(v1.is<UniquePtr<int>>()); + MOZ_RELEASE_ASSERT(v1.as<UniquePtr<int>>() == nullptr); + + Destroyer::destroyedCount = 0; + { + Variant<char, UniquePtr<Destroyer>> v3(MakeUnique<Destroyer>()); + Variant<char, UniquePtr<Destroyer>> v4(Move(v3)); + + Variant<char, UniquePtr<Destroyer>> v5('a'); + v5 = Move(v4); + + auto ptr = v5.extract<UniquePtr<Destroyer>>(); + MOZ_RELEASE_ASSERT(Destroyer::destroyedCount == 0); + } + MOZ_RELEASE_ASSERT(Destroyer::destroyedCount == 1); +} + +static void +testDestructor() +{ + printf("testDestructor\n"); + Destroyer::destroyedCount = 0; + + { + Destroyer d; + + { + Variant<char, UniquePtr<char[]>, Destroyer> v(d); + MOZ_RELEASE_ASSERT(Destroyer::destroyedCount == 0); // None detroyed yet. + } + + MOZ_RELEASE_ASSERT(Destroyer::destroyedCount == 1); // v's copy of d is destroyed. + } + + MOZ_RELEASE_ASSERT(Destroyer::destroyedCount == 2); // d is destroyed. +} + +static void +testEquality() +{ + printf("testEquality\n"); + using V = Variant<char, int>; + + V v0('a'); + V v1('b'); + V v2('b'); + V v3(42); + V v4(27); + V v5(27); + V v6(int('b')); + + MOZ_RELEASE_ASSERT(v0 != v1); + MOZ_RELEASE_ASSERT(v1 == v2); + MOZ_RELEASE_ASSERT(v2 != v3); + MOZ_RELEASE_ASSERT(v3 != v4); + MOZ_RELEASE_ASSERT(v4 == v5); + MOZ_RELEASE_ASSERT(v1 != v6); + + MOZ_RELEASE_ASSERT(v0 == v0); + MOZ_RELEASE_ASSERT(v1 == v1); + MOZ_RELEASE_ASSERT(v2 == v2); + MOZ_RELEASE_ASSERT(v3 == v3); + MOZ_RELEASE_ASSERT(v4 == v4); + MOZ_RELEASE_ASSERT(v5 == v5); + MOZ_RELEASE_ASSERT(v6 == v6); +} + +struct Describer +{ + static const char* little; + static const char* medium; + static const char* big; + + const char* match(const uint8_t&) { return little; } + const char* match(const uint32_t&) { return medium; } + const char* match(const uint64_t&) { return big; } +}; + +const char* Describer::little = "little"; +const char* Describer::medium = "medium"; +const char* Describer::big = "big"; + +static void +testMatching() +{ + printf("testMatching\n"); + using V = Variant<uint8_t, uint32_t, uint64_t>; + + Describer desc; + + V v1(uint8_t(1)); + V v2(uint32_t(2)); + V v3(uint64_t(3)); + + MOZ_RELEASE_ASSERT(v1.match(desc) == Describer::little); + MOZ_RELEASE_ASSERT(v2.match(desc) == Describer::medium); + MOZ_RELEASE_ASSERT(v3.match(desc) == Describer::big); + + const V& constRef1 = v1; + const V& constRef2 = v2; + const V& constRef3 = v3; + + MOZ_RELEASE_ASSERT(constRef1.match(desc) == Describer::little); + MOZ_RELEASE_ASSERT(constRef2.match(desc) == Describer::medium); + MOZ_RELEASE_ASSERT(constRef3.match(desc) == Describer::big); +} + +static void +testRvalueMatcher() +{ + printf("testRvalueMatcher\n"); + using V = Variant<uint8_t, uint32_t, uint64_t>; + V v(uint8_t(1)); + MOZ_RELEASE_ASSERT(v.match(Describer()) == Describer::little); +} + +int +main() +{ + testSimple(); + testCopy(); + testMove(); + testDestructor(); + testEquality(); + testMatching(); + testRvalueMatcher(); + + printf("TestVariant OK!\n"); + return 0; +} diff --git a/mfbt/tests/TestVector.cpp b/mfbt/tests/TestVector.cpp new file mode 100644 index 000000000..d969bcbc2 --- /dev/null +++ b/mfbt/tests/TestVector.cpp @@ -0,0 +1,358 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/Move.h" +#include "mozilla/UniquePtr.h" +#include "mozilla/Vector.h" + +using mozilla::detail::VectorTesting; +using mozilla::MakeUnique; +using mozilla::Move; +using mozilla::UniquePtr; +using mozilla::Vector; + +struct mozilla::detail::VectorTesting +{ + static void testReserved(); + static void testConstRange(); + static void testEmplaceBack(); + static void testReverse(); + static void testExtractRawBuffer(); + static void testExtractOrCopyRawBuffer(); +}; + +void +mozilla::detail::VectorTesting::testReserved() +{ +#ifdef DEBUG + Vector<bool> bv; + MOZ_RELEASE_ASSERT(bv.reserved() == 0); + + MOZ_RELEASE_ASSERT(bv.append(true)); + MOZ_RELEASE_ASSERT(bv.reserved() == 1); + + Vector<bool> otherbv; + MOZ_RELEASE_ASSERT(otherbv.append(false)); + MOZ_RELEASE_ASSERT(otherbv.append(true)); + MOZ_RELEASE_ASSERT(bv.appendAll(otherbv)); + MOZ_RELEASE_ASSERT(bv.reserved() == 3); + + MOZ_RELEASE_ASSERT(bv.reserve(5)); + MOZ_RELEASE_ASSERT(bv.reserved() == 5); + + MOZ_RELEASE_ASSERT(bv.reserve(1)); + MOZ_RELEASE_ASSERT(bv.reserved() == 5); + + Vector<bool> bv2(Move(bv)); + MOZ_RELEASE_ASSERT(bv.reserved() == 0); + MOZ_RELEASE_ASSERT(bv2.reserved() == 5); + + bv2.clearAndFree(); + MOZ_RELEASE_ASSERT(bv2.reserved() == 0); + + Vector<int, 42> iv; + MOZ_RELEASE_ASSERT(iv.reserved() == 0); + + MOZ_RELEASE_ASSERT(iv.append(17)); + MOZ_RELEASE_ASSERT(iv.reserved() == 1); + + Vector<int, 42> otheriv; + MOZ_RELEASE_ASSERT(otheriv.append(42)); + MOZ_RELEASE_ASSERT(otheriv.append(37)); + MOZ_RELEASE_ASSERT(iv.appendAll(otheriv)); + MOZ_RELEASE_ASSERT(iv.reserved() == 3); + + MOZ_RELEASE_ASSERT(iv.reserve(5)); + MOZ_RELEASE_ASSERT(iv.reserved() == 5); + + MOZ_RELEASE_ASSERT(iv.reserve(1)); + MOZ_RELEASE_ASSERT(iv.reserved() == 5); + + MOZ_RELEASE_ASSERT(iv.reserve(55)); + MOZ_RELEASE_ASSERT(iv.reserved() == 55); + + Vector<int, 42> iv2(Move(iv)); + MOZ_RELEASE_ASSERT(iv.reserved() == 0); + MOZ_RELEASE_ASSERT(iv2.reserved() == 55); + + iv2.clearAndFree(); + MOZ_RELEASE_ASSERT(iv2.reserved() == 0); +#endif +} + +void +mozilla::detail::VectorTesting::testConstRange() +{ +#ifdef DEBUG + Vector<int> vec; + + for (int i = 0; i < 10; i++) { + MOZ_RELEASE_ASSERT(vec.append(i)); + } + + const auto &vecRef = vec; + + Vector<int>::ConstRange range = vecRef.all(); + for (int i = 0; i < 10; i++) { + MOZ_RELEASE_ASSERT(!range.empty()); + MOZ_RELEASE_ASSERT(range.front() == i); + range.popFront(); + } +#endif +} + +namespace { + +struct S +{ + size_t j; + UniquePtr<size_t> k; + + static size_t constructCount; + static size_t moveCount; + static size_t destructCount; + + static void resetCounts() { + constructCount = 0; + moveCount = 0; + destructCount = 0; + } + + S(size_t j, size_t k) + : j(j) + , k(MakeUnique<size_t>(k)) + { + constructCount++; + } + + S(S&& rhs) + : j(rhs.j) + , k(Move(rhs.k)) + { + rhs.j = 0; + rhs.k.reset(0); + moveCount++; + } + + ~S() { + destructCount++; + } + + S(const S&) = delete; + S& operator=(const S&) = delete; +}; + +size_t S::constructCount = 0; +size_t S::moveCount = 0; +size_t S::destructCount = 0; + +} + +void +mozilla::detail::VectorTesting::testEmplaceBack() +{ + S::resetCounts(); + + Vector<S> vec; + MOZ_RELEASE_ASSERT(vec.reserve(20)); + + for (size_t i = 0; i < 10; i++) { + S s(i, i * i); + MOZ_RELEASE_ASSERT(vec.append(Move(s))); + } + + MOZ_RELEASE_ASSERT(vec.length() == 10); + MOZ_RELEASE_ASSERT(S::constructCount == 10); + MOZ_RELEASE_ASSERT(S::moveCount == 10); + + for (size_t i = 10; i < 20; i++) { + MOZ_RELEASE_ASSERT(vec.emplaceBack(i, i * i)); + } + + MOZ_RELEASE_ASSERT(vec.length() == 20); + MOZ_RELEASE_ASSERT(S::constructCount == 20); + MOZ_RELEASE_ASSERT(S::moveCount == 10); + + for (size_t i = 0; i < 20; i++) { + MOZ_RELEASE_ASSERT(vec[i].j == i); + MOZ_RELEASE_ASSERT(*vec[i].k == i * i); + } +} + +void +mozilla::detail::VectorTesting::testReverse() +{ + // Use UniquePtr to make sure that reverse() can handler move-only types. + Vector<UniquePtr<uint8_t>, 0> vec; + + // Reverse an odd number of elements. + + for (uint8_t i = 0; i < 5; i++) { + auto p = MakeUnique<uint8_t>(i); + MOZ_RELEASE_ASSERT(p); + MOZ_RELEASE_ASSERT(vec.append(mozilla::Move(p))); + } + + vec.reverse(); + + MOZ_RELEASE_ASSERT(*vec[0] == 4); + MOZ_RELEASE_ASSERT(*vec[1] == 3); + MOZ_RELEASE_ASSERT(*vec[2] == 2); + MOZ_RELEASE_ASSERT(*vec[3] == 1); + MOZ_RELEASE_ASSERT(*vec[4] == 0); + + // Reverse an even number of elements. + + vec.popBack(); + vec.reverse(); + + MOZ_RELEASE_ASSERT(*vec[0] == 1); + MOZ_RELEASE_ASSERT(*vec[1] == 2); + MOZ_RELEASE_ASSERT(*vec[2] == 3); + MOZ_RELEASE_ASSERT(*vec[3] == 4); + + // Reverse an empty vector. + + vec.clear(); + MOZ_RELEASE_ASSERT(vec.length() == 0); + vec.reverse(); + MOZ_RELEASE_ASSERT(vec.length() == 0); + + // Reverse a vector using only inline storage. + + Vector<UniquePtr<uint8_t>, 5> vec2; + for (uint8_t i = 0; i < 5; i++) { + auto p = MakeUnique<uint8_t>(i); + MOZ_RELEASE_ASSERT(p); + MOZ_RELEASE_ASSERT(vec2.append(mozilla::Move(p))); + } + + vec2.reverse(); + + MOZ_RELEASE_ASSERT(*vec2[0] == 4); + MOZ_RELEASE_ASSERT(*vec2[1] == 3); + MOZ_RELEASE_ASSERT(*vec2[2] == 2); + MOZ_RELEASE_ASSERT(*vec2[3] == 1); + MOZ_RELEASE_ASSERT(*vec2[4] == 0); +} + +void +mozilla::detail::VectorTesting::testExtractRawBuffer() +{ + S::resetCounts(); + + Vector<S, 5> vec; + MOZ_RELEASE_ASSERT(vec.reserve(5)); + for (size_t i = 0; i < 5; i++) { + vec.infallibleEmplaceBack(i, i * i); + } + MOZ_RELEASE_ASSERT(vec.length() == 5); + MOZ_ASSERT(vec.reserved() == 5); + MOZ_RELEASE_ASSERT(S::constructCount == 5); + MOZ_RELEASE_ASSERT(S::moveCount == 0); + MOZ_RELEASE_ASSERT(S::destructCount == 0); + + S* buf = vec.extractRawBuffer(); + MOZ_RELEASE_ASSERT(!buf); + MOZ_RELEASE_ASSERT(vec.length() == 5); + MOZ_ASSERT(vec.reserved() == 5); + MOZ_RELEASE_ASSERT(S::constructCount == 5); + MOZ_RELEASE_ASSERT(S::moveCount == 0); + MOZ_RELEASE_ASSERT(S::destructCount == 0); + + MOZ_RELEASE_ASSERT(vec.reserve(10)); + for (size_t i = 5; i < 10; i++) { + vec.infallibleEmplaceBack(i, i * i); + } + MOZ_RELEASE_ASSERT(vec.length() == 10); + MOZ_ASSERT(vec.reserved() == 10); + MOZ_RELEASE_ASSERT(S::constructCount == 10); + MOZ_RELEASE_ASSERT(S::moveCount == 5); + MOZ_RELEASE_ASSERT(S::destructCount == 5); + + buf = vec.extractRawBuffer(); + MOZ_RELEASE_ASSERT(buf); + MOZ_RELEASE_ASSERT(vec.length() == 0); + MOZ_ASSERT(vec.reserved() == 0); + MOZ_RELEASE_ASSERT(S::constructCount == 10); + MOZ_RELEASE_ASSERT(S::moveCount == 5); + MOZ_RELEASE_ASSERT(S::destructCount == 5); + + for (size_t i = 0; i < 10; i++) { + MOZ_RELEASE_ASSERT(buf[i].j == i); + MOZ_RELEASE_ASSERT(*buf[i].k == i * i); + } + + free(buf); +} + +void +mozilla::detail::VectorTesting::testExtractOrCopyRawBuffer() +{ + S::resetCounts(); + + Vector<S, 5> vec; + MOZ_RELEASE_ASSERT(vec.reserve(5)); + for (size_t i = 0; i < 5; i++) { + vec.infallibleEmplaceBack(i, i * i); + } + MOZ_RELEASE_ASSERT(vec.length() == 5); + MOZ_ASSERT(vec.reserved() == 5); + MOZ_RELEASE_ASSERT(S::constructCount == 5); + MOZ_RELEASE_ASSERT(S::moveCount == 0); + MOZ_RELEASE_ASSERT(S::destructCount == 0); + + S* buf = vec.extractOrCopyRawBuffer(); + MOZ_RELEASE_ASSERT(buf); + MOZ_RELEASE_ASSERT(vec.length() == 0); + MOZ_ASSERT(vec.reserved() == 0); + MOZ_RELEASE_ASSERT(S::constructCount == 5); + MOZ_RELEASE_ASSERT(S::moveCount == 5); + MOZ_RELEASE_ASSERT(S::destructCount == 5); + + for (size_t i = 0; i < 5; i++) { + MOZ_RELEASE_ASSERT(buf[i].j == i); + MOZ_RELEASE_ASSERT(*buf[i].k == i * i); + } + + S::resetCounts(); + + MOZ_RELEASE_ASSERT(vec.reserve(10)); + for (size_t i = 0; i < 10; i++) { + vec.infallibleEmplaceBack(i, i * i); + } + MOZ_RELEASE_ASSERT(vec.length() == 10); + MOZ_ASSERT(vec.reserved() == 10); + MOZ_RELEASE_ASSERT(S::constructCount == 10); + MOZ_RELEASE_ASSERT(S::moveCount == 0); + MOZ_RELEASE_ASSERT(S::destructCount == 0); + + buf = vec.extractOrCopyRawBuffer(); + MOZ_RELEASE_ASSERT(buf); + MOZ_RELEASE_ASSERT(vec.length() == 0); + MOZ_ASSERT(vec.reserved() == 0); + MOZ_RELEASE_ASSERT(S::constructCount == 10); + MOZ_RELEASE_ASSERT(S::moveCount == 0); + MOZ_RELEASE_ASSERT(S::destructCount == 0); + + for (size_t i = 0; i < 10; i++) { + MOZ_RELEASE_ASSERT(buf[i].j == i); + MOZ_RELEASE_ASSERT(*buf[i].k == i * i); + } + + free(buf); +} + +int +main() +{ + VectorTesting::testReserved(); + VectorTesting::testConstRange(); + VectorTesting::testEmplaceBack(); + VectorTesting::testReverse(); + VectorTesting::testExtractRawBuffer(); + VectorTesting::testExtractOrCopyRawBuffer(); +} diff --git a/mfbt/tests/TestWeakPtr.cpp b/mfbt/tests/TestWeakPtr.cpp new file mode 100644 index 000000000..15060f00d --- /dev/null +++ b/mfbt/tests/TestWeakPtr.cpp @@ -0,0 +1,123 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/WeakPtr.h" + +using mozilla::SupportsWeakPtr; +using mozilla::WeakPtr; + +// To have a class C support weak pointers, inherit from SupportsWeakPtr<C>. +class C : public SupportsWeakPtr<C> +{ +public: + MOZ_DECLARE_WEAKREFERENCE_TYPENAME(C) + + int mNum; + + C() + : mNum(0) + {} + + ~C() + { + // Setting mNum in the destructor allows us to test against use-after-free below + mNum = 0xDEAD; + } + + void act() {} + + bool isConst() { + return false; + } + + bool isConst() const { + return true; + } +}; + +bool isConst(C*) +{ + return false; +} + +bool isConst(const C*) +{ + return true; +} + +int +main() +{ + C* c1 = new C; + MOZ_RELEASE_ASSERT(c1->mNum == 0); + + // Get weak pointers to c1. The first time, + // a reference-counted WeakReference object is created that + // can live beyond the lifetime of 'c1'. The WeakReference + // object will be notified of 'c1's destruction. + WeakPtr<C> w1 = c1; + // Test a weak pointer for validity before using it. + MOZ_RELEASE_ASSERT(w1); + MOZ_RELEASE_ASSERT(w1 == c1); + w1->mNum = 1; + w1->act(); + + // Test taking another WeakPtr<C> to c1 + WeakPtr<C> w2 = c1; + MOZ_RELEASE_ASSERT(w2); + MOZ_RELEASE_ASSERT(w2 == c1); + MOZ_RELEASE_ASSERT(w2 == w1); + MOZ_RELEASE_ASSERT(w2->mNum == 1); + + // Test a WeakPtr<const C> + WeakPtr<const C> w3const = c1; + MOZ_RELEASE_ASSERT(w3const); + MOZ_RELEASE_ASSERT(w3const == c1); + MOZ_RELEASE_ASSERT(w3const == w1); + MOZ_RELEASE_ASSERT(w3const == w2); + MOZ_RELEASE_ASSERT(w3const->mNum == 1); + + // Test const-correctness of operator-> and operator T* + MOZ_RELEASE_ASSERT(!w1->isConst()); + MOZ_RELEASE_ASSERT(w3const->isConst()); + MOZ_RELEASE_ASSERT(!isConst(w1)); + MOZ_RELEASE_ASSERT(isConst(w3const)); + + // Test that when a WeakPtr is destroyed, it does not destroy the object that it points to, + // and it does not affect other WeakPtrs pointing to the same object (e.g. it does not + // destroy the WeakReference object). + { + WeakPtr<C> w4local = c1; + MOZ_RELEASE_ASSERT(w4local == c1); + } + // Now w4local has gone out of scope. If that had destroyed c1, then the following would fail + // for sure (see C::~C()). + MOZ_RELEASE_ASSERT(c1->mNum == 1); + // Check that w4local going out of scope hasn't affected other WeakPtr's pointing to c1 + MOZ_RELEASE_ASSERT(w1 == c1); + MOZ_RELEASE_ASSERT(w2 == c1); + + // Now construct another C object and test changing what object a WeakPtr points to + C* c2 = new C; + c2->mNum = 2; + MOZ_RELEASE_ASSERT(w2->mNum == 1); // w2 was pointing to c1 + w2 = c2; + MOZ_RELEASE_ASSERT(w2); + MOZ_RELEASE_ASSERT(w2 == c2); + MOZ_RELEASE_ASSERT(w2 != c1); + MOZ_RELEASE_ASSERT(w2 != w1); + MOZ_RELEASE_ASSERT(w2->mNum == 2); + + // Destroying the underlying object clears weak pointers to it. + // It should not affect pointers that are not currently pointing to it. + delete c1; + MOZ_RELEASE_ASSERT(!w1, "Deleting an object should clear WeakPtr's to it."); + MOZ_RELEASE_ASSERT(!w3const, "Deleting an object should clear WeakPtr's to it."); + MOZ_RELEASE_ASSERT(w2, "Deleting an object should not clear WeakPtr that are not pointing to it."); + + delete c2; + MOZ_RELEASE_ASSERT(!w2, "Deleting an object should clear WeakPtr's to it."); +} diff --git a/mfbt/tests/TestXorShift128PlusRNG.cpp b/mfbt/tests/TestXorShift128PlusRNG.cpp new file mode 100644 index 000000000..dbe83d049 --- /dev/null +++ b/mfbt/tests/TestXorShift128PlusRNG.cpp @@ -0,0 +1,115 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include <math.h> + +#include "mozilla/Assertions.h" +#include "mozilla/PodOperations.h" +#include "mozilla/XorShift128PlusRNG.h" + +using mozilla::non_crypto::XorShift128PlusRNG; + +static void +TestDumbSequence() +{ + XorShift128PlusRNG rng(1, 4); + + // Calculated by hand following the algorithm given in the paper. The upper + // bits are mostly zero because we started with a poor seed; once it has run + // for a while, we'll get an even mix of ones and zeros in all 64 bits. + MOZ_RELEASE_ASSERT(rng.next() == 0x800049); + MOZ_RELEASE_ASSERT(rng.next() == 0x3000186); + MOZ_RELEASE_ASSERT(rng.next() == 0x400003001145); + + // Using ldexp here lets us write out the mantissa in hex, so we can compare + // them with the results generated by hand. + MOZ_RELEASE_ASSERT(rng.nextDouble() + == ldexp(static_cast<double>(0x1400003105049), -53)); + MOZ_RELEASE_ASSERT(rng.nextDouble() + == ldexp(static_cast<double>(0x2000802e49146), -53)); + MOZ_RELEASE_ASSERT(rng.nextDouble() + == ldexp(static_cast<double>(0x248300468544d), -53)); +} + +static size_t +Population(uint64_t n) +{ + size_t pop = 0; + + while (n > 0) { + n &= n-1; // Clear the rightmost 1-bit in n. + pop++; + } + + return pop; +} + +static void +TestPopulation() +{ + XorShift128PlusRNG rng(698079309544035222ULL, 6012389156611637584ULL); + + // Give it some time to warm up; it should tend towards more + // even distributions of zeros and ones. + for (size_t i = 0; i < 40; i++) + rng.next(); + + for (size_t i = 0; i < 40; i++) { + size_t pop = Population(rng.next()); + MOZ_RELEASE_ASSERT(24 <= pop && pop <= 40); + } +} + +static void +TestSetState() +{ + static const uint64_t seed[2] = { 1795644156779822404ULL, 14162896116325912595ULL }; + XorShift128PlusRNG rng(seed[0], seed[1]); + + const size_t n = 10; + uint64_t log[n]; + + for (size_t i = 0; i < n; i++) + log[i] = rng.next(); + + rng.setState(seed[0], seed[1]); + + for (size_t i = 0; i < n; i++) + MOZ_RELEASE_ASSERT(log[i] == rng.next()); +} + +static void +TestDoubleDistribution() +{ + XorShift128PlusRNG rng(0xa207aaede6859736, 0xaca6ca5060804791); + + const size_t n = 100; + size_t bins[n]; + mozilla::PodArrayZero(bins); + + // This entire file runs in 0.006s on my laptop. Generating + // more numbers lets us put tighter bounds on the bins. + for (size_t i = 0; i < 100000; i++) { + double d = rng.nextDouble(); + MOZ_RELEASE_ASSERT(0.0 <= d && d < 1.0); + bins[(int) (d * n)]++; + } + + for (size_t i = 0; i < n; i++) { + MOZ_RELEASE_ASSERT(900 <= bins[i] && bins[i] <= 1100); + } +} + +int +main() +{ + TestDumbSequence(); + TestPopulation(); + TestSetState(); + TestDoubleDistribution(); + + return 0; +} diff --git a/mfbt/tests/moz.build b/mfbt/tests/moz.build new file mode 100644 index 000000000..f96117e03 --- /dev/null +++ b/mfbt/tests/moz.build @@ -0,0 +1,76 @@ +# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*- +# vim: set filetype=python: +# This Source Code Form is subject to the terms of the Mozilla Public +# License, v. 2.0. If a copy of the MPL was not distributed with this +# file, You can obtain one at http://mozilla.org/MPL/2.0/. + +CppUnitTests([ + 'TestArray', + 'TestArrayUtils', + 'TestAtomics', + 'TestBinarySearch', + 'TestBloomFilter', + 'TestBufferList', + 'TestCasting', + 'TestCeilingFloor', + 'TestCheckedInt', + 'TestCountPopulation', + 'TestCountZeroes', + 'TestEndian', + 'TestEnumeratedArray', + 'TestEnumSet', + 'TestEnumTypeTraits', + 'TestFastBernoulliTrial', + 'TestFloatingPoint', + 'TestFunction', + 'TestIntegerPrintfMacros', + 'TestIntegerRange', + 'TestJSONWriter', + 'TestLinkedList', + 'TestMacroArgs', + 'TestMacroForEach', + 'TestMathAlgorithms', + 'TestMaybe', + 'TestNotNull', + 'TestPair', + 'TestRange', + 'TestRefPtr', + 'TestRollingMean', + 'TestSaturate', + 'TestScopeExit', + 'TestSegmentedVector', + 'TestSHA1', + 'TestSplayTree', + 'TestTemplateLib', + 'TestTuple', + 'TestTypedEnum', + 'TestTypeTraits', + 'TestUniquePtr', + 'TestVariant', + 'TestVector', + 'TestWeakPtr', + 'TestXorShift128PlusRNG', +]) + +if not CONFIG['MOZ_ASAN']: + CppUnitTests([ + 'TestPoisonArea', + ]) + +# Since we link directly with MFBT object files, define IMPL_MFBT +DEFINES['IMPL_MFBT'] = True + +DISABLE_STL_WRAPPING = True + +if CONFIG['_MSC_VER']: + CXXFLAGS += [ + '-wd4275', # non dll-interface class used as base for dll-interface class + '-wd4530', # C++ exception handler used, but unwind semantics are not enabled + ] + +USE_LIBS += [ + 'mfbt', +] + +if CONFIG['GNU_CXX']: + CXXFLAGS += ['-Wno-error=shadow'] |