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Diffstat (limited to 'js/src/vm/MallocProvider.h')
-rw-r--r-- | js/src/vm/MallocProvider.h | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/js/src/vm/MallocProvider.h b/js/src/vm/MallocProvider.h new file mode 100644 index 000000000..0fd40d0cd --- /dev/null +++ b/js/src/vm/MallocProvider.h @@ -0,0 +1,199 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- + * vim: set ts=8 sts=4 et sw=4 tw=99: + * 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/. */ + +/* + * Hierarchy of SpiderMonkey system memory allocators: + * + * - System {m,c,re}alloc/new/free: Overridden by jemalloc in most + * environments. Do not use these functions directly. + * + * - js_{m,c,re}alloc/new/free: Wraps the system allocators and adds a + * failure injection framework for use by the fuzzers as well as templated, + * typesafe variants. See js/public/Utility.h. + * + * - AllocPolicy: An interface for the js allocators, for use with templates. + * These allocators are for system memory whose lifetime is not associated + * with a GC thing. See js/src/jsalloc.h. + * + * - SystemAllocPolicy: No extra functionality over bare allocators. + * + * - TempAllocPolicy: Adds automatic error reporting to the provided + * JSContext when allocations fail. + * + * - RuntimeAllocPolicy: Forwards to the JSRuntime MallocProvider. + * + * - ZoneAllocPolicy: Forwards to the Zone MallocProvider. + * + * - MallocProvider. A mixin base class that handles automatically updating + * the GC's state in response to allocations that are tied to a GC lifetime + * or are for a particular GC purpose. These allocators must only be used + * for memory that will be freed when a GC thing is swept. + * + * - gc::Zone: Automatically triggers zone GC. + * - JSRuntime: Automatically triggers full GC. + * - ThreadsafeContext > ExclusiveContext > JSContext: + * Dispatches directly to the runtime. + */ + +#ifndef vm_MallocProvider_h +#define vm_MallocProvider_h + +#include "mozilla/Attributes.h" +#include "mozilla/Likely.h" + +#include "js/UniquePtr.h" +#include "js/Utility.h" + +namespace js { + +template<class Client> +struct MallocProvider +{ + template <class T> + T* maybe_pod_malloc(size_t numElems) { + T* p = js_pod_malloc<T>(numElems); + if (MOZ_LIKELY(p)) + client()->updateMallocCounter(numElems * sizeof(T)); + return p; + } + + template <class T> + T* maybe_pod_calloc(size_t numElems) { + T* p = js_pod_calloc<T>(numElems); + if (MOZ_LIKELY(p)) + client()->updateMallocCounter(numElems * sizeof(T)); + return p; + } + + template <class T> + T* maybe_pod_realloc(T* prior, size_t oldSize, size_t newSize) { + T* p = js_pod_realloc(prior, oldSize, newSize); + if (MOZ_LIKELY(p)) { + // For compatibility we do not account for realloc that decreases + // previously allocated memory. + if (newSize > oldSize) + client()->updateMallocCounter((newSize - oldSize) * sizeof(T)); + } + return p; + } + + template <class T> + T* pod_malloc() { + return pod_malloc<T>(1); + } + + template <class T> + T* pod_malloc(size_t numElems) { + T* p = maybe_pod_malloc<T>(numElems); + if (MOZ_LIKELY(p)) + return p; + size_t bytes; + if (MOZ_UNLIKELY(!CalculateAllocSize<T>(numElems, &bytes))) { + client()->reportAllocationOverflow(); + return nullptr; + } + p = (T*)client()->onOutOfMemory(AllocFunction::Malloc, bytes); + if (p) + client()->updateMallocCounter(bytes); + return p; + } + + template <class T, class U> + T* pod_malloc_with_extra(size_t numExtra) { + size_t bytes; + if (MOZ_UNLIKELY((!CalculateAllocSizeWithExtra<T, U>(numExtra, &bytes)))) { + client()->reportAllocationOverflow(); + return nullptr; + } + T* p = static_cast<T*>(js_malloc(bytes)); + if (MOZ_LIKELY(p)) { + client()->updateMallocCounter(bytes); + return p; + } + p = (T*)client()->onOutOfMemory(AllocFunction::Malloc, bytes); + if (p) + client()->updateMallocCounter(bytes); + return p; + } + + template <class T> + UniquePtr<T[], JS::FreePolicy> + make_pod_array(size_t numElems) { + return UniquePtr<T[], JS::FreePolicy>(pod_malloc<T>(numElems)); + } + + template <class T> + T* pod_calloc() { + return pod_calloc<T>(1); + } + + template <class T> + T* pod_calloc(size_t numElems) { + T* p = maybe_pod_calloc<T>(numElems); + if (MOZ_LIKELY(p)) + return p; + size_t bytes; + if (MOZ_UNLIKELY(!CalculateAllocSize<T>(numElems, &bytes))) { + client()->reportAllocationOverflow(); + return nullptr; + } + p = (T*)client()->onOutOfMemory(AllocFunction::Calloc, bytes); + if (p) + client()->updateMallocCounter(bytes); + return p; + } + + template <class T, class U> + T* pod_calloc_with_extra(size_t numExtra) { + size_t bytes; + if (MOZ_UNLIKELY((!CalculateAllocSizeWithExtra<T, U>(numExtra, &bytes)))) { + client()->reportAllocationOverflow(); + return nullptr; + } + T* p = static_cast<T*>(js_calloc(bytes)); + if (p) { + client()->updateMallocCounter(bytes); + return p; + } + p = (T*)client()->onOutOfMemory(AllocFunction::Calloc, bytes); + if (p) + client()->updateMallocCounter(bytes); + return p; + } + + template <class T> + UniquePtr<T[], JS::FreePolicy> + make_zeroed_pod_array(size_t numElems) + { + return UniquePtr<T[], JS::FreePolicy>(pod_calloc<T>(numElems)); + } + + template <class T> + T* pod_realloc(T* prior, size_t oldSize, size_t newSize) { + T* p = maybe_pod_realloc(prior, oldSize, newSize); + if (MOZ_LIKELY(p)) + return p; + size_t bytes; + if (MOZ_UNLIKELY(!CalculateAllocSize<T>(newSize, &bytes))) { + client()->reportAllocationOverflow(); + return nullptr; + } + p = (T*)client()->onOutOfMemory(AllocFunction::Realloc, bytes, prior); + if (p && newSize > oldSize) + client()->updateMallocCounter((newSize - oldSize) * sizeof(T)); + return p; + } + + JS_DECLARE_NEW_METHODS(new_, pod_malloc<uint8_t>, MOZ_ALWAYS_INLINE) + JS_DECLARE_MAKE_METHODS(make_unique, new_, MOZ_ALWAYS_INLINE) + + private: + Client* client() { return static_cast<Client*>(this); } +}; + +} /* namespace js */ + +#endif /* vm_MallocProvider_h */ |