diff options
author | Matt A. Tobin <mattatobin@localhost.localdomain> | 2018-02-02 04:16:08 -0500 |
---|---|---|
committer | Matt A. Tobin <mattatobin@localhost.localdomain> | 2018-02-02 04:16:08 -0500 |
commit | 5f8de423f190bbb79a62f804151bc24824fa32d8 (patch) | |
tree | 10027f336435511475e392454359edea8e25895d /js/src/jscntxt.h | |
parent | 49ee0794b5d912db1f95dce6eb52d781dc210db5 (diff) | |
download | UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar.gz UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar.lz UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar.xz UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.zip |
Add m-esr52 at 52.6.0
Diffstat (limited to 'js/src/jscntxt.h')
-rw-r--r-- | js/src/jscntxt.h | 856 |
1 files changed, 856 insertions, 0 deletions
diff --git a/js/src/jscntxt.h b/js/src/jscntxt.h new file mode 100644 index 000000000..0a2841242 --- /dev/null +++ b/js/src/jscntxt.h @@ -0,0 +1,856 @@ +/* -*- 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/. */ + +/* JS execution context. */ + +#ifndef jscntxt_h +#define jscntxt_h + +#include "mozilla/MemoryReporting.h" + +#include "js/CharacterEncoding.h" +#include "js/GCVector.h" +#include "js/Utility.h" +#include "js/Vector.h" +#include "vm/Caches.h" +#include "vm/Runtime.h" + +#ifdef _MSC_VER +#pragma warning(push) +#pragma warning(disable:4100) /* Silence unreferenced formal parameter warnings */ +#endif + +struct DtoaState; + +namespace js { + +namespace jit { +class JitContext; +class DebugModeOSRVolatileJitFrameIterator; +} // namespace jit + +typedef HashSet<Shape*> ShapeSet; + +/* Detects cycles when traversing an object graph. */ +class MOZ_RAII AutoCycleDetector +{ + public: + using Set = HashSet<JSObject*, MovableCellHasher<JSObject*>, SystemAllocPolicy>; + + AutoCycleDetector(JSContext* cx, HandleObject objArg + MOZ_GUARD_OBJECT_NOTIFIER_PARAM) + : cx(cx), obj(cx, objArg), cyclic(true) + { + MOZ_GUARD_OBJECT_NOTIFIER_INIT; + } + + ~AutoCycleDetector(); + + bool init(); + + bool foundCycle() { return cyclic; } + + private: + Generation hashsetGenerationAtInit; + JSContext* cx; + RootedObject obj; + Set::AddPtr hashsetAddPointer; + bool cyclic; + MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER +}; + +/* Updates references in the cycle detection set if the GC moves them. */ +extern void +TraceCycleDetectionSet(JSTracer* trc, AutoCycleDetector::Set& set); + +struct AutoResolving; + +namespace frontend { class CompileError; } + +/* + * Execution Context Overview: + * + * Several different structures may be used to provide a context for operations + * on the VM. Each context is thread local, but varies in what data it can + * access and what other threads may be running. + * + * - ExclusiveContext is used by threads operating in one compartment/zone, + * where other threads may operate in other compartments, but *not* the same + * compartment or zone which the ExclusiveContext is in. A thread with an + * ExclusiveContext may enter the atoms compartment and atomize strings, in + * which case a lock is used. + * + * - JSContext is used only by the runtime's main thread. The context may + * operate in any compartment or zone which is not used by an ExclusiveContext, + * and will only run in parallel with threads using such contexts. + * + * A JSContext coerces to an ExclusiveContext. + */ + +struct HelperThread; + +class ExclusiveContext : public ContextFriendFields, + public MallocProvider<ExclusiveContext> +{ + friend class gc::ArenaLists; + friend class AutoCompartment; + friend class AutoLockForExclusiveAccess; + friend struct StackBaseShape; + friend void JSScript::initCompartment(ExclusiveContext* cx); + friend class jit::JitContext; + + // runtime_ is private to hide it from JSContext. JSContext inherits from + // JSRuntime, so it's more efficient to use the base class. + JSRuntime* const runtime_; + + // The thread on which this context is running, if this is not a JSContext. + HelperThread* helperThread_; + + public: + enum ContextKind { + Context_JS, + Context_Exclusive + }; + + private: + ContextKind contextKind_; + + protected: + // Background threads get a read-only copy of the main thread's + // ContextOptions. + JS::ContextOptions options_; + + public: + PerThreadData* perThreadData; + + ExclusiveContext(JSRuntime* rt, PerThreadData* pt, ContextKind kind, + const JS::ContextOptions& options); + + bool isJSContext() const { + return contextKind_ == Context_JS; + } + + JSContext* maybeJSContext() const { + if (isJSContext()) + return (JSContext*) this; + return nullptr; + } + + JSContext* asJSContext() const { + // Note: there is no way to perform an unchecked coercion from a + // ThreadSafeContext to a JSContext. This ensures that trying to use + // the context as a JSContext off the main thread will nullptr crash + // rather than race. + MOZ_ASSERT(isJSContext()); + return maybeJSContext(); + } + + // In some cases we could potentially want to do operations that require a + // JSContext while running off the main thread. While this should never + // actually happen, the wide enough API for working off the main thread + // makes such operations impossible to rule out. Rather than blindly using + // asJSContext() and crashing afterwards, this method may be used to watch + // for such cases and produce either a soft failure in release builds or + // an assertion failure in debug builds. + bool shouldBeJSContext() const { + MOZ_ASSERT(isJSContext()); + return isJSContext(); + } + + const JS::ContextOptions& options() const { + return options_; + } + + bool runtimeMatches(JSRuntime* rt) const { + return runtime_ == rt; + } + + protected: + js::gc::ArenaLists* arenas_; + + public: + inline js::gc::ArenaLists* arenas() const { return arenas_; } + + template <typename T> + bool isInsideCurrentZone(T thing) const { + return thing->zoneFromAnyThread() == zone_; + } + + template <typename T> + inline bool isInsideCurrentCompartment(T thing) const { + return thing->compartment() == compartment_; + } + + void* onOutOfMemory(js::AllocFunction allocFunc, size_t nbytes, void* reallocPtr = nullptr) { + if (!isJSContext()) { + addPendingOutOfMemory(); + return nullptr; + } + return runtime_->onOutOfMemory(allocFunc, nbytes, reallocPtr, asJSContext()); + } + + /* Clear the pending exception (if any) due to OOM. */ + void recoverFromOutOfMemory(); + + inline void updateMallocCounter(size_t nbytes) { + // Note: this is racy. + runtime_->updateMallocCounter(zone_, nbytes); + } + + void reportAllocationOverflow() { + js::ReportAllocationOverflow(this); + } + + // Accessors for immutable runtime data. + JSAtomState& names() { return *runtime_->commonNames; } + StaticStrings& staticStrings() { return *runtime_->staticStrings; } + SharedImmutableStringsCache& sharedImmutableStrings() { + return runtime_->sharedImmutableStrings(); + } + bool isPermanentAtomsInitialized() { return !!runtime_->permanentAtoms; } + FrozenAtomSet& permanentAtoms() { return *runtime_->permanentAtoms; } + WellKnownSymbols& wellKnownSymbols() { return *runtime_->wellKnownSymbols; } + JS::BuildIdOp buildIdOp() { return runtime_->buildIdOp; } + const JS::AsmJSCacheOps& asmJSCacheOps() { return runtime_->asmJSCacheOps; } + PropertyName* emptyString() { return runtime_->emptyString; } + FreeOp* defaultFreeOp() { return runtime_->defaultFreeOp(); } + void* contextAddressForJit() { return runtime_->unsafeContextFromAnyThread(); } + void* runtimeAddressOfInterruptUint32() { return runtime_->addressOfInterruptUint32(); } + void* stackLimitAddress(StackKind kind) { return &nativeStackLimit[kind]; } + void* stackLimitAddressForJitCode(StackKind kind); + uintptr_t stackLimit(StackKind kind) { return nativeStackLimit[kind]; } + uintptr_t stackLimitForJitCode(StackKind kind); + size_t gcSystemPageSize() { return gc::SystemPageSize(); } + bool jitSupportsFloatingPoint() const { return runtime_->jitSupportsFloatingPoint; } + bool jitSupportsUnalignedAccesses() const { return runtime_->jitSupportsUnalignedAccesses; } + bool jitSupportsSimd() const { return runtime_->jitSupportsSimd; } + bool lcovEnabled() const { return runtime_->lcovOutput.isEnabled(); } + + // Thread local data that may be accessed freely. + DtoaState* dtoaState() { + return perThreadData->dtoaState; + } + + frontend::NameCollectionPool& frontendCollectionPool() { + return perThreadData->frontendCollectionPool; + } + + /* + * "Entering" a compartment changes cx->compartment (which changes + * cx->global). Note that this does not push any InterpreterFrame which means + * that it is possible for cx->fp()->compartment() != cx->compartment. + * This is not a problem since, in general, most places in the VM cannot + * know that they were called from script (e.g., they may have been called + * through the JSAPI via JS_CallFunction) and thus cannot expect fp. + * + * Compartments should be entered/left in a LIFO fasion. The depth of this + * enter/leave stack is maintained by enterCompartmentDepth_ and queried by + * hasEnteredCompartment. + * + * To enter a compartment, code should prefer using AutoCompartment over + * manually calling cx->enterCompartment/leaveCompartment. + */ + protected: + unsigned enterCompartmentDepth_; + + inline void setCompartment(JSCompartment* comp, + const js::AutoLockForExclusiveAccess* maybeLock = nullptr); + public: + bool hasEnteredCompartment() const { + return enterCompartmentDepth_ > 0; + } +#ifdef DEBUG + unsigned getEnterCompartmentDepth() const { + return enterCompartmentDepth_; + } +#endif + + // If |c| or |oldCompartment| is the atoms compartment, the + // |exclusiveAccessLock| must be held. + inline void enterCompartment(JSCompartment* c, + const js::AutoLockForExclusiveAccess* maybeLock = nullptr); + inline void enterNullCompartment(); + inline void leaveCompartment(JSCompartment* oldCompartment, + const js::AutoLockForExclusiveAccess* maybeLock = nullptr); + + void setHelperThread(HelperThread* helperThread); + HelperThread* helperThread() const { return helperThread_; } + + // Threads with an ExclusiveContext may freely access any data in their + // compartment and zone. + JSCompartment* compartment() const { + return compartment_; + } + JS::Zone* zone() const { + MOZ_ASSERT_IF(!compartment(), !zone_); + MOZ_ASSERT_IF(compartment(), js::GetCompartmentZone(compartment()) == zone_); + return zone_; + } + + // Zone local methods that can be used freely from an ExclusiveContext. + inline js::LifoAlloc& typeLifoAlloc(); + + // Current global. This is only safe to use within the scope of the + // AutoCompartment from which it's called. + inline js::Handle<js::GlobalObject*> global() const; + + // Methods to access runtime data that must be protected by locks. + AtomSet& atoms(js::AutoLockForExclusiveAccess& lock) { + return runtime_->atoms(lock); + } + JSCompartment* atomsCompartment(js::AutoLockForExclusiveAccess& lock) { + return runtime_->atomsCompartment(lock); + } + SymbolRegistry& symbolRegistry(js::AutoLockForExclusiveAccess& lock) { + return runtime_->symbolRegistry(lock); + } + ScriptDataTable& scriptDataTable(AutoLockForExclusiveAccess& lock) { + return runtime_->scriptDataTable(lock); + } + + // Methods specific to any HelperThread for the context. + bool addPendingCompileError(frontend::CompileError** err); + void addPendingOverRecursed(); + void addPendingOutOfMemory(); +}; + +void ReportOverRecursed(JSContext* cx, unsigned errorNumber); + +} /* namespace js */ + +struct JSContext : public js::ExclusiveContext, + public JSRuntime +{ + explicit JSContext(JSRuntime* parentRuntime); + ~JSContext(); + + bool init(uint32_t maxBytes, uint32_t maxNurseryBytes); + + // For names that exist in both ExclusiveContext and JSRuntime, pick the + // ExclusiveContext version. + using ExclusiveContext::atomsCompartment; + using ExclusiveContext::buildIdOp; + using ExclusiveContext::emptyString; + using ExclusiveContext::jitSupportsSimd; + using ExclusiveContext::make_pod_array; + using ExclusiveContext::make_unique; + using ExclusiveContext::new_; + using ExclusiveContext::permanentAtoms; + using ExclusiveContext::pod_calloc; + using ExclusiveContext::pod_malloc; + using ExclusiveContext::staticStrings; + using ExclusiveContext::updateMallocCounter; + using ExclusiveContext::wellKnownSymbols; + + JSRuntime* runtime() { return this; } + js::PerThreadData& mainThread() { return this->JSRuntime::mainThread; } + + static size_t offsetOfActivation() { + return offsetof(JSContext, activation_); + } + static size_t offsetOfWasmActivation() { + return offsetof(JSContext, wasmActivationStack_); + } + static size_t offsetOfProfilingActivation() { + return offsetof(JSContext, profilingActivation_); + } + static size_t offsetOfCompartment() { + return offsetof(JSContext, compartment_); + } + + friend class js::ExclusiveContext; + friend class JS::AutoSaveExceptionState; + friend class js::jit::DebugModeOSRVolatileJitFrameIterator; + friend void js::ReportOverRecursed(JSContext*, unsigned errorNumber); + + private: + /* Exception state -- the exception member is a GC root by definition. */ + bool throwing; /* is there a pending exception? */ + JS::PersistentRooted<JS::Value> unwrappedException_; /* most-recently-thrown exception */ + + // True if the exception currently being thrown is by result of + // ReportOverRecursed. See Debugger::slowPathOnExceptionUnwind. + bool overRecursed_; + + // True if propagating a forced return from an interrupt handler during + // debug mode. + bool propagatingForcedReturn_; + + // A stack of live iterators that need to be updated in case of debug mode + // OSR. + js::jit::DebugModeOSRVolatileJitFrameIterator* liveVolatileJitFrameIterators_; + + public: + js::ContextCaches caches; + + int32_t reportGranularity; /* see vm/Probes.h */ + + js::AutoResolving* resolvingList; + + /* True if generating an error, to prevent runaway recursion. */ + bool generatingError; + + /* State for object and array toSource conversion. */ + js::AutoCycleDetector::Set cycleDetectorSet; + + /* Client opaque pointer. */ + void* data; + + void resetJitStackLimit(); + + public: + + /* + * Return: + * - The newest scripted frame's version, if there is such a frame. + * - The version from the compartment. + * - The default version. + * + * Note: if this ever shows up in a profile, just add caching! + */ + JSVersion findVersion() const; + + void initJitStackLimit(); + + JS::ContextOptions& options() { + return options_; + } + + js::LifoAlloc& tempLifoAlloc() { return runtime()->tempLifoAlloc; } + + unsigned outstandingRequests;/* number of JS_BeginRequest calls + without the corresponding + JS_EndRequest. */ + + bool jitIsBroken; + + void updateJITEnabled(); + + /* + * Youngest frame of a saved stack that will be picked up as an async stack + * by any new Activation, and is nullptr when no async stack should be used. + * + * The JS::AutoSetAsyncStackForNewCalls class can be used to set this. + * + * New activations will reset this to nullptr on construction after getting + * the current value, and will restore the previous value on destruction. + */ + JS::PersistentRooted<js::SavedFrame*> asyncStackForNewActivations; + + /* + * Value of asyncCause to be attached to asyncStackForNewActivations. + */ + const char* asyncCauseForNewActivations; + + /* + * True if the async call was explicitly requested, e.g. via + * callFunctionWithAsyncStack. + */ + bool asyncCallIsExplicit; + + /* Whether this context has JS frames on the stack. */ + bool currentlyRunning() const; + + bool currentlyRunningInInterpreter() const { + return activation()->isInterpreter(); + } + bool currentlyRunningInJit() const { + return activation()->isJit(); + } + js::InterpreterFrame* interpreterFrame() const { + return activation()->asInterpreter()->current(); + } + js::InterpreterRegs& interpreterRegs() const { + return activation()->asInterpreter()->regs(); + } + + /* + * Get the topmost script and optional pc on the stack. By default, this + * function only returns a JSScript in the current compartment, returning + * nullptr if the current script is in a different compartment. This + * behavior can be overridden by passing ALLOW_CROSS_COMPARTMENT. + */ + enum MaybeAllowCrossCompartment { + DONT_ALLOW_CROSS_COMPARTMENT = false, + ALLOW_CROSS_COMPARTMENT = true + }; + inline JSScript* currentScript(jsbytecode** pc = nullptr, + MaybeAllowCrossCompartment = DONT_ALLOW_CROSS_COMPARTMENT) const; + + // The generational GC nursery may only be used on the main thread. + inline js::Nursery& nursery() { + return gc.nursery; + } + + void minorGC(JS::gcreason::Reason reason) { + gc.minorGC(reason); + } + + public: + bool isExceptionPending() { + return throwing; + } + + MOZ_MUST_USE + bool getPendingException(JS::MutableHandleValue rval); + + bool isThrowingOutOfMemory(); + bool isThrowingDebuggeeWouldRun(); + bool isClosingGenerator(); + + void setPendingException(const js::Value& v); + + void clearPendingException() { + throwing = false; + overRecursed_ = false; + unwrappedException_.setUndefined(); + } + + bool isThrowingOverRecursed() const { return throwing && overRecursed_; } + bool isPropagatingForcedReturn() const { return propagatingForcedReturn_; } + void setPropagatingForcedReturn() { propagatingForcedReturn_ = true; } + void clearPropagatingForcedReturn() { propagatingForcedReturn_ = false; } + + /* + * See JS_SetTrustedPrincipals in jsapi.h. + * Note: !cx->compartment is treated as trusted. + */ + inline bool runningWithTrustedPrincipals() const; + + JS_FRIEND_API(size_t) sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf) const; + + void mark(JSTracer* trc); + + private: + /* + * The allocation code calls the function to indicate either OOM failure + * when p is null or that a memory pressure counter has reached some + * threshold when p is not null. The function takes the pointer and not + * a boolean flag to minimize the amount of code in its inlined callers. + */ + JS_FRIEND_API(void) checkMallocGCPressure(void* p); +}; /* struct JSContext */ + +namespace js { + +struct MOZ_RAII AutoResolving { + public: + enum Kind { + LOOKUP, + WATCH + }; + + AutoResolving(JSContext* cx, HandleObject obj, HandleId id, Kind kind = LOOKUP + MOZ_GUARD_OBJECT_NOTIFIER_PARAM) + : context(cx), object(obj), id(id), kind(kind), link(cx->resolvingList) + { + MOZ_GUARD_OBJECT_NOTIFIER_INIT; + MOZ_ASSERT(obj); + cx->resolvingList = this; + } + + ~AutoResolving() { + MOZ_ASSERT(context->resolvingList == this); + context->resolvingList = link; + } + + bool alreadyStarted() const { + return link && alreadyStartedSlow(); + } + + private: + bool alreadyStartedSlow() const; + + JSContext* const context; + HandleObject object; + HandleId id; + Kind const kind; + AutoResolving* const link; + MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER +}; + +/* + * Create and destroy functions for JSContext, which is manually allocated + * and exclusively owned. + */ +extern JSContext* +NewContext(uint32_t maxBytes, uint32_t maxNurseryBytes, JSRuntime* parentRuntime); + +extern void +DestroyContext(JSContext* cx); + +enum ErrorArgumentsType { + ArgumentsAreUnicode, + ArgumentsAreASCII, + ArgumentsAreLatin1, + ArgumentsAreUTF8 +}; + +/* + * Loads and returns a self-hosted function by name. For performance, define + * the property name in vm/CommonPropertyNames.h. + * + * Defined in SelfHosting.cpp. + */ +JSFunction* +SelfHostedFunction(JSContext* cx, HandlePropertyName propName); + +#ifdef va_start +extern bool +ReportErrorVA(JSContext* cx, unsigned flags, const char* format, + ErrorArgumentsType argumentsType, va_list ap); + +extern bool +ReportErrorNumberVA(JSContext* cx, unsigned flags, JSErrorCallback callback, + void* userRef, const unsigned errorNumber, + ErrorArgumentsType argumentsType, va_list ap); + +extern bool +ReportErrorNumberUCArray(JSContext* cx, unsigned flags, JSErrorCallback callback, + void* userRef, const unsigned errorNumber, + const char16_t** args); +#endif + +extern bool +ExpandErrorArgumentsVA(ExclusiveContext* cx, JSErrorCallback callback, + void* userRef, const unsigned errorNumber, + const char16_t** messageArgs, + ErrorArgumentsType argumentsType, + JSErrorReport* reportp, va_list ap); + +/* |callee| requires a usage string provided by JS_DefineFunctionsWithHelp. */ +extern void +ReportUsageErrorASCII(JSContext* cx, HandleObject callee, const char* msg); + +/* + * Prints a full report and returns true if the given report is non-nullptr + * and the report doesn't have the JSREPORT_WARNING flag set or reportWarnings + * is true. + * Returns false otherwise. + */ +extern bool +PrintError(JSContext* cx, FILE* file, JS::ConstUTF8CharsZ toStringResult, + JSErrorReport* report, bool reportWarnings); + +/* + * Send a JSErrorReport to the warningReporter callback. + */ +void +CallWarningReporter(JSContext* cx, JSErrorReport* report); + +extern bool +ReportIsNotDefined(JSContext* cx, HandlePropertyName name); + +extern bool +ReportIsNotDefined(JSContext* cx, HandleId id); + +/* + * Report an attempt to access the property of a null or undefined value (v). + */ +extern bool +ReportIsNullOrUndefined(JSContext* cx, int spindex, HandleValue v, HandleString fallback); + +extern void +ReportMissingArg(JSContext* cx, js::HandleValue v, unsigned arg); + +/* + * Report error using js_DecompileValueGenerator(cx, spindex, v, fallback) as + * the first argument for the error message. If the error message has less + * then 3 arguments, use null for arg1 or arg2. + */ +extern bool +ReportValueErrorFlags(JSContext* cx, unsigned flags, const unsigned errorNumber, + int spindex, HandleValue v, HandleString fallback, + const char* arg1, const char* arg2); + +#define ReportValueError(cx,errorNumber,spindex,v,fallback) \ + ((void)ReportValueErrorFlags(cx, JSREPORT_ERROR, errorNumber, \ + spindex, v, fallback, nullptr, nullptr)) + +#define ReportValueError2(cx,errorNumber,spindex,v,fallback,arg1) \ + ((void)ReportValueErrorFlags(cx, JSREPORT_ERROR, errorNumber, \ + spindex, v, fallback, arg1, nullptr)) + +#define ReportValueError3(cx,errorNumber,spindex,v,fallback,arg1,arg2) \ + ((void)ReportValueErrorFlags(cx, JSREPORT_ERROR, errorNumber, \ + spindex, v, fallback, arg1, arg2)) + +} /* namespace js */ + +extern const JSErrorFormatString js_ErrorFormatString[JSErr_Limit]; + +namespace js { + +MOZ_ALWAYS_INLINE bool +CheckForInterrupt(JSContext* cx) +{ + MOZ_ASSERT(!cx->isExceptionPending()); + // Add an inline fast-path since we have to check for interrupts in some hot + // C++ loops of library builtins. + JSRuntime* rt = cx->runtime(); + if (MOZ_UNLIKELY(rt->hasPendingInterrupt())) + return rt->handleInterrupt(cx); + return true; +} + +/************************************************************************/ + +/* AutoArrayRooter roots an external array of Values. */ +class MOZ_RAII AutoArrayRooter : private JS::AutoGCRooter +{ + public: + AutoArrayRooter(JSContext* cx, size_t len, Value* vec + MOZ_GUARD_OBJECT_NOTIFIER_PARAM) + : JS::AutoGCRooter(cx, len), array(vec) + { + MOZ_GUARD_OBJECT_NOTIFIER_INIT; + MOZ_ASSERT(tag_ >= 0); + } + + void changeLength(size_t newLength) { + tag_ = ptrdiff_t(newLength); + MOZ_ASSERT(tag_ >= 0); + } + + void changeArray(Value* newArray, size_t newLength) { + changeLength(newLength); + array = newArray; + } + + Value* start() { + return array; + } + + size_t length() { + MOZ_ASSERT(tag_ >= 0); + return size_t(tag_); + } + + MutableHandleValue handleAt(size_t i) { + MOZ_ASSERT(i < size_t(tag_)); + return MutableHandleValue::fromMarkedLocation(&array[i]); + } + HandleValue handleAt(size_t i) const { + MOZ_ASSERT(i < size_t(tag_)); + return HandleValue::fromMarkedLocation(&array[i]); + } + MutableHandleValue operator[](size_t i) { + MOZ_ASSERT(i < size_t(tag_)); + return MutableHandleValue::fromMarkedLocation(&array[i]); + } + HandleValue operator[](size_t i) const { + MOZ_ASSERT(i < size_t(tag_)); + return HandleValue::fromMarkedLocation(&array[i]); + } + + friend void JS::AutoGCRooter::trace(JSTracer* trc); + + private: + Value* array; + MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER +}; + +class AutoAssertNoException +{ +#ifdef DEBUG + JSContext* cx; + bool hadException; +#endif + + public: + explicit AutoAssertNoException(JSContext* cx) +#ifdef DEBUG + : cx(cx), + hadException(cx->isExceptionPending()) +#endif + { + } + + ~AutoAssertNoException() + { + MOZ_ASSERT_IF(!hadException, !cx->isExceptionPending()); + } +}; + +/* Exposed intrinsics for the JITs. */ +bool intrinsic_IsSuspendedStarGenerator(JSContext* cx, unsigned argc, Value* vp); + +class MOZ_RAII AutoLockForExclusiveAccess +{ + JSRuntime* runtime; + + void init(JSRuntime* rt) { + runtime = rt; + if (runtime->numExclusiveThreads) { + runtime->exclusiveAccessLock.lock(); + } else { + MOZ_ASSERT(!runtime->mainThreadHasExclusiveAccess); +#ifdef DEBUG + runtime->mainThreadHasExclusiveAccess = true; +#endif + } + } + + public: + explicit AutoLockForExclusiveAccess(ExclusiveContext* cx MOZ_GUARD_OBJECT_NOTIFIER_PARAM) { + MOZ_GUARD_OBJECT_NOTIFIER_INIT; + init(cx->runtime_); + } + explicit AutoLockForExclusiveAccess(JSRuntime* rt MOZ_GUARD_OBJECT_NOTIFIER_PARAM) { + MOZ_GUARD_OBJECT_NOTIFIER_INIT; + init(rt); + } + explicit AutoLockForExclusiveAccess(JSContext* cx MOZ_GUARD_OBJECT_NOTIFIER_PARAM) { + MOZ_GUARD_OBJECT_NOTIFIER_INIT; + init(cx->runtime()); + } + ~AutoLockForExclusiveAccess() { + if (runtime->numExclusiveThreads) { + runtime->exclusiveAccessLock.unlock(); + } else { + MOZ_ASSERT(runtime->mainThreadHasExclusiveAccess); +#ifdef DEBUG + runtime->mainThreadHasExclusiveAccess = false; +#endif + } + } + + MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER +}; + +/* + * ExclusiveContext variants of encoding functions, for off-main-thread use. + * Refer to CharacterEncoding.h for details. + */ +extern JS::TwoByteCharsZ +LossyUTF8CharsToNewTwoByteCharsZ(ExclusiveContext* cx, const JS::UTF8Chars utf8, size_t* outlen); + +extern JS::TwoByteCharsZ +LossyUTF8CharsToNewTwoByteCharsZ(ExclusiveContext* cx, const JS::ConstUTF8CharsZ& utf8, size_t* outlen); + +extern JS::Latin1CharsZ +LossyUTF8CharsToNewLatin1CharsZ(ExclusiveContext* cx, const JS::UTF8Chars utf8, size_t* outlen); + +} /* namespace js */ + +#ifdef _MSC_VER +#pragma warning(pop) +#endif + +inline JSContext* +JSRuntime::unsafeContextFromAnyThread() +{ + return static_cast<JSContext*>(this); +} + +inline JSContext* +JSRuntime::contextFromMainThread() +{ + MOZ_ASSERT(CurrentThreadCanAccessRuntime(this)); + return unsafeContextFromAnyThread(); +} + +#endif /* jscntxt_h */ |