webkitgtk-2.16.5HEADwebkitgtk-2.16.5master

1 files changed, 653 insertions, 388 deletions

diff --git a/Source/JavaScriptCore/runtime/VM.h b/Source/JavaScriptCore/runtime/VM.h
index 1de423e0e..732b26e4e 100644
--- a/Source/JavaScriptCore/runtime/VM.h
+++ b/Source/JavaScriptCore/runtime/VM.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2008, 2009, 2013 Apple Inc. All rights reserved.
+ * Copyright (C) 2008-2017 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -10,7 +10,7 @@
  * 2.  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. 
- * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ * 3.  Neither the name of Apple Inc. ("Apple") nor the names of
  *     its contributors may be used to endorse or promote products derived
  *     from this software without specific prior written permission. 
  *
@@ -26,527 +26,792 @@
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef VM_h
-#define VM_h
+#pragma once
 
+#include "CallData.h"
+#include "ConcurrentJSLock.h"
+#include "ControlFlowProfiler.h"
 #include "DateInstanceCache.h"
+#include "DeleteAllCodeEffort.h"
+#include "ExceptionEventLocation.h"
 #include "ExecutableAllocator.h"
-#include "GPRInfo.h"
+#include "FunctionHasExecutedCache.h"
 #include "Heap.h"
 #include "Intrinsic.h"
 #include "JITThunks.h"
 #include "JSCJSValue.h"
+#include "JSDestructibleObjectSubspace.h"
 #include "JSLock.h"
-#include "LLIntData.h"
+#include "JSSegmentedVariableObjectSubspace.h"
+#include "JSStringSubspace.h"
 #include "MacroAssemblerCodeRef.h"
+#include "Microtask.h"
 #include "NumericStrings.h"
-#include "ProfilerDatabase.h"
 #include "PrivateName.h"
 #include "PrototypeMap.h"
 #include "SmallStrings.h"
+#include "SourceCode.h"
 #include "Strong.h"
+#include "Subspace.h"
+#include "TemplateRegistryKeyTable.h"
 #include "ThunkGenerators.h"
-#include "TypedArrayController.h"
-#include "Watchdog.h"
+#include "VMEntryRecord.h"
 #include "Watchpoint.h"
-#include "WeakRandom.h"
+#include <wtf/Bag.h>
 #include <wtf/BumpPointerAllocator.h>
 #include <wtf/DateMath.h>
+#include <wtf/Deque.h>
+#include <wtf/DoublyLinkedList.h>
 #include <wtf/Forward.h>
 #include <wtf/HashMap.h>
 #include <wtf/HashSet.h>
-#include <wtf/RefCountedArray.h>
-#include <wtf/SimpleStats.h>
 #include <wtf/StackBounds.h>
+#include <wtf/Stopwatch.h>
 #include <wtf/ThreadSafeRefCounted.h>
 #include <wtf/ThreadSpecific.h>
 #include <wtf/WTFThreadData.h>
+#include <wtf/text/SymbolRegistry.h>
 #include <wtf/text/WTFString.h>
 #if ENABLE(REGEXP_TRACING)
 #include <wtf/ListHashSet.h>
 #endif
 
+namespace WTF {
+class SimpleStats;
+} // namespace WTF
+using WTF::SimpleStats;
+
 namespace JSC {
 
-    class CodeBlock;
-    class CodeCache;
-    class CommonIdentifiers;
-    class ExecState;
-    class HandleStack;
-    class Identifier;
-    class IdentifierTable;
-    class Interpreter;
-    class JSGlobalObject;
-    class JSObject;
-    class Keywords;
-    class LLIntOffsetsExtractor;
-    class LegacyProfiler;
-    class NativeExecutable;
-    class ParserArena;
-    class RegExpCache;
-    class SourceProvider;
-    class SourceProviderCache;
-    struct StackFrame;
-    class Stringifier;
-    class Structure;
+class BuiltinExecutables;
+class BytecodeIntrinsicRegistry;
+class CodeBlock;
+class CodeCache;
+class CommonIdentifiers;
+class CustomGetterSetter;
+class ExecState;
+class Exception;
+class ExceptionScope;
+class HandleStack;
+class TypeProfiler;
+class TypeProfilerLog;
+class HasOwnPropertyCache;
+class HeapProfiler;
+class Identifier;
+class Interpreter;
+class JSCustomGetterSetterFunction;
+class JSGlobalObject;
+class JSObject;
+class JSWebAssemblyInstance;
+class LLIntOffsetsExtractor;
+class NativeExecutable;
+class RegExpCache;
+class Register;
+class RegisterAtOffsetList;
+#if ENABLE(SAMPLING_PROFILER)
+class SamplingProfiler;
+#endif
+class ShadowChicken;
+class ScriptExecutable;
+class SourceProvider;
+class SourceProviderCache;
+class StackFrame;
+class Structure;
 #if ENABLE(REGEXP_TRACING)
-    class RegExp;
+class RegExp;
 #endif
-    class UnlinkedCodeBlock;
-    class UnlinkedEvalCodeBlock;
-    class UnlinkedFunctionExecutable;
-    class UnlinkedProgramCodeBlock;
-    class VMEntryScope;
-    class Watchpoint;
-    class WatchpointSet;
+class Symbol;
+class TypedArrayController;
+class UnlinkedCodeBlock;
+class UnlinkedEvalCodeBlock;
+class UnlinkedFunctionExecutable;
+class UnlinkedProgramCodeBlock;
+class UnlinkedModuleProgramCodeBlock;
+class VirtualRegister;
+class VMEntryScope;
+class Watchdog;
+class Watchpoint;
+class WatchpointSet;
 
 #if ENABLE(DFG_JIT)
-    namespace DFG {
-    class LongLivedState;
-    class Worklist;
-    }
+namespace DFG {
+class LongLivedState;
+}
 #endif // ENABLE(DFG_JIT)
 #if ENABLE(FTL_JIT)
-    namespace FTL {
-    class Thunks;
-    }
+namespace FTL {
+class Thunks;
+}
 #endif // ENABLE(FTL_JIT)
+namespace CommonSlowPaths {
+struct ArityCheckData;
+}
+namespace Profiler {
+class Database;
+}
+namespace DOMJIT {
+class Signature;
+}
+#if ENABLE(WEBASSEMBLY)
+namespace Wasm {
+class SignatureInformation;
+}
+#endif
 
-    struct HashTable;
-    struct Instruction;
+struct HashTable;
+struct Instruction;
 
-    struct LocalTimeOffsetCache {
-        LocalTimeOffsetCache()
-            : start(0.0)
-            , end(-1.0)
-            , increment(0.0)
-            , timeType(WTF::UTCTime)
-        {
-        }
-        
-        void reset()
-        {
-            offset = LocalTimeOffset();
-            start = 0.0;
-            end = -1.0;
-            increment = 0.0;
-            timeType = WTF::UTCTime;
-        }
+struct LocalTimeOffsetCache {
+    LocalTimeOffsetCache()
+        : start(0.0)
+        , end(-1.0)
+        , increment(0.0)
+        , timeType(WTF::UTCTime)
+    {
+    }
 
-        LocalTimeOffset offset;
-        double start;
-        double end;
-        double increment;
-        WTF::TimeType timeType;
-    };
+    void reset()
+    {
+        offset = LocalTimeOffset();
+        start = 0.0;
+        end = -1.0;
+        increment = 0.0;
+        timeType = WTF::UTCTime;
+    }
+
+    LocalTimeOffset offset;
+    double start;
+    double end;
+    double increment;
+    WTF::TimeType timeType;
+};
+
+class QueuedTask {
+    WTF_MAKE_NONCOPYABLE(QueuedTask);
+    WTF_MAKE_FAST_ALLOCATED;
+public:
+    void run();
+
+    QueuedTask(VM& vm, JSGlobalObject* globalObject, Ref<Microtask>&& microtask)
+        : m_globalObject(vm, globalObject)
+        , m_microtask(WTFMove(microtask))
+    {
+    }
+
+private:
+    Strong<JSGlobalObject> m_globalObject;
+    Ref<Microtask> m_microtask;
+};
 
-    class ConservativeRoots;
+class ConservativeRoots;
 
 #if COMPILER(MSVC)
 #pragma warning(push)
 #pragma warning(disable: 4200) // Disable "zero-sized array in struct/union" warning
 #endif
-    struct ScratchBuffer {
-        ScratchBuffer()
-        {
-            u.m_activeLength = 0;
-        }
+struct ScratchBuffer {
+    ScratchBuffer()
+    {
+        u.m_activeLength = 0;
+    }
 
-        static ScratchBuffer* create(size_t size)
-        {
-            ScratchBuffer* result = new (fastMalloc(ScratchBuffer::allocationSize(size))) ScratchBuffer;
+    static ScratchBuffer* create(size_t size)
+    {
+        ScratchBuffer* result = new (fastMalloc(ScratchBuffer::allocationSize(size))) ScratchBuffer;
 
-            return result;
-        }
+        return result;
+    }
 
-        static size_t allocationSize(size_t bufferSize) { return sizeof(ScratchBuffer) + bufferSize; }
-        void setActiveLength(size_t activeLength) { u.m_activeLength = activeLength; }
-        size_t activeLength() const { return u.m_activeLength; };
-        size_t* activeLengthPtr() { return &u.m_activeLength; };
-        void* dataBuffer() { return m_buffer; }
+    static size_t allocationSize(size_t bufferSize) { return sizeof(ScratchBuffer) + bufferSize; }
+    void setActiveLength(size_t activeLength) { u.m_activeLength = activeLength; }
+    size_t activeLength() const { return u.m_activeLength; };
+    size_t* activeLengthPtr() { return &u.m_activeLength; };
+    void* dataBuffer() { return m_buffer; }
 
-        union {
-            size_t m_activeLength;
-            double pad; // Make sure m_buffer is double aligned.
-        } u;
+    union {
+        size_t m_activeLength;
+        double pad; // Make sure m_buffer is double aligned.
+    } u;
 #if CPU(MIPS) && (defined WTF_MIPS_ARCH_REV && WTF_MIPS_ARCH_REV == 2)
-        void* m_buffer[0] __attribute__((aligned(8)));
+    void* m_buffer[0] __attribute__((aligned(8)));
 #else
-        void* m_buffer[0];
+    void* m_buffer[0];
 #endif
-    };
+};
 #if COMPILER(MSVC)
 #pragma warning(pop)
 #endif
 
-    class VM : public ThreadSafeRefCounted<VM> {
-    public:
-        // WebCore has a one-to-one mapping of threads to VMs;
-        // either create() or createLeaked() should only be called once
-        // on a thread, this is the 'default' VM (it uses the
-        // thread's default string uniquing table from wtfThreadData).
-        // API contexts created using the new context group aware interface
-        // create APIContextGroup objects which require less locking of JSC
-        // than the old singleton APIShared VM created for use by
-        // the original API.
-        enum VMType { Default, APIContextGroup, APIShared };
-        
-        struct ClientData {
-            JS_EXPORT_PRIVATE virtual ~ClientData() = 0;
-        };
-
-        bool isSharedInstance() { return vmType == APIShared; }
-        bool usingAPI() { return vmType != Default; }
-        JS_EXPORT_PRIVATE static bool sharedInstanceExists();
-        JS_EXPORT_PRIVATE static VM& sharedInstance();
-
-        JS_EXPORT_PRIVATE static PassRefPtr<VM> create(HeapType = SmallHeap);
-        JS_EXPORT_PRIVATE static PassRefPtr<VM> createLeaked(HeapType = SmallHeap);
-        static PassRefPtr<VM> createContextGroup(HeapType = SmallHeap);
-        JS_EXPORT_PRIVATE ~VM();
-
-        void makeUsableFromMultipleThreads() { heap.machineThreads().makeUsableFromMultipleThreads(); }
-        
-#if ENABLE(DFG_JIT)
-        DFG::Worklist* ensureWorklist();
-#endif // ENABLE(DFG_JIT)
+class VM : public ThreadSafeRefCounted<VM>, public DoublyLinkedListNode<VM> {
+public:
+    // WebCore has a one-to-one mapping of threads to VMs;
+    // either create() or createLeaked() should only be called once
+    // on a thread, this is the 'default' VM (it uses the
+    // thread's default string uniquing table from wtfThreadData).
+    // API contexts created using the new context group aware interface
+    // create APIContextGroup objects which require less locking of JSC
+    // than the old singleton APIShared VM created for use by
+    // the original API.
+    enum VMType { Default, APIContextGroup, APIShared };
+
+    struct ClientData {
+        JS_EXPORT_PRIVATE virtual ~ClientData() = 0;
+    };
 
-    private:
-        RefPtr<JSLock> m_apiLock;
+    bool isSharedInstance() { return vmType == APIShared; }
+    bool usingAPI() { return vmType != Default; }
+    JS_EXPORT_PRIVATE static bool sharedInstanceExists();
+    JS_EXPORT_PRIVATE static VM& sharedInstance();
 
-    public:
+    JS_EXPORT_PRIVATE static Ref<VM> create(HeapType = SmallHeap);
+    JS_EXPORT_PRIVATE static Ref<VM> createLeaked(HeapType = SmallHeap);
+    static Ref<VM> createContextGroup(HeapType = SmallHeap);
+    JS_EXPORT_PRIVATE ~VM();
+
+    JS_EXPORT_PRIVATE Watchdog& ensureWatchdog();
+    Watchdog* watchdog() { return m_watchdog.get(); }
+
+    HeapProfiler* heapProfiler() const { return m_heapProfiler.get(); }
+    JS_EXPORT_PRIVATE HeapProfiler& ensureHeapProfiler();
+
+#if ENABLE(SAMPLING_PROFILER)
+    SamplingProfiler* samplingProfiler() { return m_samplingProfiler.get(); }
+    JS_EXPORT_PRIVATE SamplingProfiler& ensureSamplingProfiler(RefPtr<Stopwatch>&&);
+#endif
+
+private:
+    RefPtr<JSLock> m_apiLock;
+
+public:
 #if ENABLE(ASSEMBLER)
-        // executableAllocator should be destructed after the heap, as the heap can call executableAllocator
-        // in its destructor.
-        ExecutableAllocator executableAllocator;
+    // executableAllocator should be destructed after the heap, as the heap can call executableAllocator
+    // in its destructor.
+    ExecutableAllocator executableAllocator;
 #endif
 
-        // The heap should be just after executableAllocator and before other members to ensure that it's
-        // destructed after all the objects that reference it.
-        Heap heap;
-        
+    // The heap should be just after executableAllocator and before other members to ensure that it's
+    // destructed after all the objects that reference it.
+    Heap heap;
+    
+    Subspace auxiliarySpace;
+    
+    // Whenever possible, use subspaceFor<CellType>(vm) to get one of these subspaces.
+    Subspace cellSpace;
+    Subspace destructibleCellSpace;
+    JSStringSubspace stringSpace;
+    JSDestructibleObjectSubspace destructibleObjectSpace;
+    JSSegmentedVariableObjectSubspace segmentedVariableObjectSpace;
+
 #if ENABLE(DFG_JIT)
-        OwnPtr<DFG::LongLivedState> dfgState;
-        RefPtr<DFG::Worklist> worklist;
+    std::unique_ptr<DFG::LongLivedState> dfgState;
 #endif // ENABLE(DFG_JIT)
 
-        VMType vmType;
-        ClientData* clientData;
-        ExecState* topCallFrame;
-        Watchdog watchdog;
-
-        const OwnPtr<const HashTable> arrayConstructorTable;
-        const OwnPtr<const HashTable> arrayPrototypeTable;
-        const OwnPtr<const HashTable> booleanPrototypeTable;
-        const OwnPtr<const HashTable> dataViewTable;
-        const OwnPtr<const HashTable> dateTable;
-        const OwnPtr<const HashTable> dateConstructorTable;
-        const OwnPtr<const HashTable> errorPrototypeTable;
-        const OwnPtr<const HashTable> globalObjectTable;
-        const OwnPtr<const HashTable> jsonTable;
-        const OwnPtr<const HashTable> numberConstructorTable;
-        const OwnPtr<const HashTable> numberPrototypeTable;
-        const OwnPtr<const HashTable> objectConstructorTable;
-        const OwnPtr<const HashTable> privateNamePrototypeTable;
-        const OwnPtr<const HashTable> regExpTable;
-        const OwnPtr<const HashTable> regExpConstructorTable;
-        const OwnPtr<const HashTable> regExpPrototypeTable;
-        const OwnPtr<const HashTable> stringConstructorTable;
-#if ENABLE(PROMISES)
-        const OwnPtr<const HashTable> promisePrototypeTable;
-        const OwnPtr<const HashTable> promiseConstructorTable;
+    VMType vmType;
+    ClientData* clientData;
+    VMEntryFrame* topVMEntryFrame;
+    // NOTE: When throwing an exception while rolling back the call frame, this may be equal to
+    // topVMEntryFrame.
+    // FIXME: This should be a void*, because it might not point to a CallFrame.
+    // https://bugs.webkit.org/show_bug.cgi?id=160441
+    ExecState* topCallFrame;
+    JSWebAssemblyInstance* topJSWebAssemblyInstance;
+    Strong<Structure> structureStructure;
+    Strong<Structure> structureRareDataStructure;
+    Strong<Structure> terminatedExecutionErrorStructure;
+    Strong<Structure> stringStructure;
+    Strong<Structure> propertyNameIteratorStructure;
+    Strong<Structure> propertyNameEnumeratorStructure;
+    Strong<Structure> customGetterSetterStructure;
+    Strong<Structure> scopedArgumentsTableStructure;
+    Strong<Structure> apiWrapperStructure;
+    Strong<Structure> JSScopeStructure;
+    Strong<Structure> executableStructure;
+    Strong<Structure> nativeExecutableStructure;
+    Strong<Structure> evalExecutableStructure;
+    Strong<Structure> programExecutableStructure;
+    Strong<Structure> functionExecutableStructure;
+#if ENABLE(WEBASSEMBLY)
+    Strong<Structure> webAssemblyCalleeStructure;
+    Strong<Structure> webAssemblyToJSCalleeStructure;
+    Strong<JSCell> webAssemblyToJSCallee;
 #endif
+    Strong<Structure> moduleProgramExecutableStructure;
+    Strong<Structure> regExpStructure;
+    Strong<Structure> symbolStructure;
+    Strong<Structure> symbolTableStructure;
+    Strong<Structure> fixedArrayStructure;
+    Strong<Structure> sourceCodeStructure;
+    Strong<Structure> scriptFetcherStructure;
+    Strong<Structure> structureChainStructure;
+    Strong<Structure> sparseArrayValueMapStructure;
+    Strong<Structure> templateRegistryKeyStructure;
+    Strong<Structure> arrayBufferNeuteringWatchpointStructure;
+    Strong<Structure> unlinkedFunctionExecutableStructure;
+    Strong<Structure> unlinkedProgramCodeBlockStructure;
+    Strong<Structure> unlinkedEvalCodeBlockStructure;
+    Strong<Structure> unlinkedFunctionCodeBlockStructure;
+    Strong<Structure> unlinkedModuleProgramCodeBlockStructure;
+    Strong<Structure> propertyTableStructure;
+    Strong<Structure> weakMapDataStructure;
+    Strong<Structure> inferredValueStructure;
+    Strong<Structure> inferredTypeStructure;
+    Strong<Structure> inferredTypeTableStructure;
+    Strong<Structure> functionRareDataStructure;
+    Strong<Structure> exceptionStructure;
+    Strong<Structure> promiseDeferredStructure;
+    Strong<Structure> internalPromiseDeferredStructure;
+    Strong<Structure> nativeStdFunctionCellStructure;
+    Strong<Structure> programCodeBlockStructure;
+    Strong<Structure> moduleProgramCodeBlockStructure;
+    Strong<Structure> evalCodeBlockStructure;
+    Strong<Structure> functionCodeBlockStructure;
+    Strong<Structure> hashMapBucketSetStructure;
+    Strong<Structure> hashMapBucketMapStructure;
+    Strong<Structure> hashMapImplSetStructure;
+    Strong<Structure> hashMapImplMapStructure;
+
+    Strong<JSCell> iterationTerminator;
+    Strong<JSCell> emptyPropertyNameEnumerator;
+
+#if ENABLE(WEBASSEMBLY)
+    std::once_flag m_wasmSignatureInformationOnceFlag;
+    std::unique_ptr<Wasm::SignatureInformation> m_wasmSignatureInformation;
+#endif
+    
+    JSCell* currentlyDestructingCallbackObject;
+    const ClassInfo* currentlyDestructingCallbackObjectClassInfo;
+
+    AtomicStringTable* m_atomicStringTable;
+    WTF::SymbolRegistry m_symbolRegistry;
+    TemplateRegistryKeyTable m_templateRegistryKeytable;
+    CommonIdentifiers* propertyNames;
+    const ArgList* emptyList;
+    SmallStrings smallStrings;
+    NumericStrings numericStrings;
+    DateInstanceCache dateInstanceCache;
+    std::unique_ptr<SimpleStats> machineCodeBytesPerBytecodeWordForBaselineJIT;
+    WeakGCMap<std::pair<CustomGetterSetter*, int>, JSCustomGetterSetterFunction> customGetterSetterFunctionMap;
+    WeakGCMap<StringImpl*, JSString, PtrHash<StringImpl*>> stringCache;
+    Strong<JSString> lastCachedString;
+
+    AtomicStringTable* atomicStringTable() const { return m_atomicStringTable; }
+    WTF::SymbolRegistry& symbolRegistry() { return m_symbolRegistry; }
+
+    TemplateRegistryKeyTable& templateRegistryKeyTable() { return m_templateRegistryKeytable; }
+
+    WeakGCMap<SymbolImpl*, Symbol, PtrHash<SymbolImpl*>> symbolImplToSymbolMap;
+
+    enum class DeletePropertyMode {
+        // Default behaviour of deleteProperty, matching the spec.
+        Default,
+        // This setting causes deleteProperty to force deletion of all
+        // properties including those that are non-configurable (DontDelete).
+        IgnoreConfigurable
+    };
+
+    DeletePropertyMode deletePropertyMode()
+    {
+        return m_deletePropertyMode;
+    }
 
-        Strong<Structure> structureStructure;
-        Strong<Structure> structureRareDataStructure;
-        Strong<Structure> debuggerActivationStructure;
-        Strong<Structure> terminatedExecutionErrorStructure;
-        Strong<Structure> stringStructure;
-        Strong<Structure> notAnObjectStructure;
-        Strong<Structure> propertyNameIteratorStructure;
-        Strong<Structure> getterSetterStructure;
-        Strong<Structure> apiWrapperStructure;
-        Strong<Structure> JSScopeStructure;
-        Strong<Structure> executableStructure;
-        Strong<Structure> nativeExecutableStructure;
-        Strong<Structure> evalExecutableStructure;
-        Strong<Structure> programExecutableStructure;
-        Strong<Structure> functionExecutableStructure;
-        Strong<Structure> regExpStructure;
-        Strong<Structure> symbolTableStructure;
-        Strong<Structure> structureChainStructure;
-        Strong<Structure> sparseArrayValueMapStructure;
-        Strong<Structure> arrayBufferNeuteringWatchpointStructure;
-        Strong<Structure> withScopeStructure;
-        Strong<Structure> unlinkedFunctionExecutableStructure;
-        Strong<Structure> unlinkedProgramCodeBlockStructure;
-        Strong<Structure> unlinkedEvalCodeBlockStructure;
-        Strong<Structure> unlinkedFunctionCodeBlockStructure;
-        Strong<Structure> propertyTableStructure;
-        Strong<Structure> mapDataStructure;
-        Strong<Structure> weakMapDataStructure;
-        Strong<Structure> promiseDeferredStructure;
-        Strong<Structure> promiseReactionStructure;
-        Strong<JSCell> iterationTerminator;
-
-        IdentifierTable* identifierTable;
-        CommonIdentifiers* propertyNames;
-        const MarkedArgumentBuffer* emptyList; // Lists are supposed to be allocated on the stack to have their elements properly marked, which is not the case here - but this list has nothing to mark.
-        SmallStrings smallStrings;
-        NumericStrings numericStrings;
-        DateInstanceCache dateInstanceCache;
-        WTF::SimpleStats machineCodeBytesPerBytecodeWordForBaselineJIT;
-
-        void setInDefineOwnProperty(bool inDefineOwnProperty)
+    class DeletePropertyModeScope {
+    public:
+        DeletePropertyModeScope(VM& vm, DeletePropertyMode mode)
+            : m_vm(vm)
+            , m_previousMode(vm.m_deletePropertyMode)
         {
-            m_inDefineOwnProperty = inDefineOwnProperty;
+            m_vm.m_deletePropertyMode = mode;
         }
 
-        bool isInDefineOwnProperty()
+        ~DeletePropertyModeScope()
         {
-            return m_inDefineOwnProperty;
+            m_vm.m_deletePropertyMode = m_previousMode;
         }
 
-        LegacyProfiler* enabledProfiler() { return m_enabledProfiler; }
-        void setEnabledProfiler(LegacyProfiler*);
-
-        void* enabledProfilerAddress() { return &m_enabledProfiler; }
+    private:
+        VM& m_vm;
+        DeletePropertyMode m_previousMode;
+    };
 
-#if ENABLE(JIT) && ENABLE(LLINT)
-        bool canUseJIT() { return m_canUseJIT; }
-#elif ENABLE(JIT)
-        bool canUseJIT() { return true; } // jit only
+#if ENABLE(JIT)
+    bool canUseJIT() { return m_canUseJIT; }
 #else
-        bool canUseJIT() { return false; } // interpreter only
+    bool canUseJIT() { return false; } // interpreter only
 #endif
 
 #if ENABLE(YARR_JIT)
-        bool canUseRegExpJIT() { return m_canUseRegExpJIT; }
+    bool canUseRegExpJIT() { return m_canUseRegExpJIT; }
 #else
-        bool canUseRegExpJIT() { return false; } // interpreter only
+    bool canUseRegExpJIT() { return false; } // interpreter only
 #endif
 
-        SourceProviderCache* addSourceProviderCache(SourceProvider*);
-        void clearSourceProviderCaches();
+    SourceProviderCache* addSourceProviderCache(SourceProvider*);
+    void clearSourceProviderCaches();
 
-        PrototypeMap prototypeMap;
+    PrototypeMap prototypeMap;
 
-        OwnPtr<ParserArena> parserArena;
-        typedef HashMap<RefPtr<SourceProvider>, RefPtr<SourceProviderCache>> SourceProviderCacheMap;
-        SourceProviderCacheMap sourceProviderCacheMap;
-        OwnPtr<Keywords> keywords;
-        Interpreter* interpreter;
+    typedef HashMap<RefPtr<SourceProvider>, RefPtr<SourceProviderCache>> SourceProviderCacheMap;
+    SourceProviderCacheMap sourceProviderCacheMap;
+    Interpreter* interpreter;
 #if ENABLE(JIT)
-        OwnPtr<JITThunks> jitStubs;
-        MacroAssemblerCodeRef getCTIStub(ThunkGenerator generator)
-        {
-            return jitStubs->ctiStub(this, generator);
-        }
-        NativeExecutable* getHostFunction(NativeFunction, Intrinsic);
-#endif
+    std::unique_ptr<JITThunks> jitStubs;
+    MacroAssemblerCodeRef getCTIStub(ThunkGenerator generator)
+    {
+        return jitStubs->ctiStub(this, generator);
+    }
+    
+    std::unique_ptr<RegisterAtOffsetList> allCalleeSaveRegisterOffsets;
+    
+    RegisterAtOffsetList* getAllCalleeSaveRegisterOffsets() { return allCalleeSaveRegisterOffsets.get(); }
+
+#endif // ENABLE(JIT)
+    std::unique_ptr<CommonSlowPaths::ArityCheckData> arityCheckData;
 #if ENABLE(FTL_JIT)
-        std::unique_ptr<FTL::Thunks> ftlThunks;
+    std::unique_ptr<FTL::Thunks> ftlThunks;
 #endif
-        NativeExecutable* getHostFunction(NativeFunction, NativeFunction constructor);
+    NativeExecutable* getHostFunction(NativeFunction, NativeFunction constructor, const String& name);
+    NativeExecutable* getHostFunction(NativeFunction, Intrinsic, NativeFunction constructor, const DOMJIT::Signature*, const String& name);
 
-        static ptrdiff_t exceptionOffset()
-        {
-            return OBJECT_OFFSETOF(VM, m_exception);
-        }
+    static ptrdiff_t exceptionOffset()
+    {
+        return OBJECT_OFFSETOF(VM, m_exception);
+    }
 
-        static ptrdiff_t callFrameForThrowOffset()
-        {
-            return OBJECT_OFFSETOF(VM, callFrameForThrow);
-        }
+    static ptrdiff_t callFrameForCatchOffset()
+    {
+        return OBJECT_OFFSETOF(VM, callFrameForCatch);
+    }
 
-        static ptrdiff_t targetMachinePCForThrowOffset()
-        {
-            return OBJECT_OFFSETOF(VM, targetMachinePCForThrow);
-        }
+    static ptrdiff_t targetMachinePCForThrowOffset()
+    {
+        return OBJECT_OFFSETOF(VM, targetMachinePCForThrow);
+    }
 
-        JS_EXPORT_PRIVATE void clearException();
-        JS_EXPORT_PRIVATE void clearExceptionStack();
-        void getExceptionInfo(JSValue& exception, RefCountedArray<StackFrame>& exceptionStack);
-        void setExceptionInfo(JSValue& exception, RefCountedArray<StackFrame>& exceptionStack);
-        JSValue exception() const { return m_exception; }
-        JSValue* addressOfException() { return &m_exception; }
-        const RefCountedArray<StackFrame>& exceptionStack() const { return m_exceptionStack; }
-
-        JS_EXPORT_PRIVATE JSValue throwException(ExecState*, JSValue);
-        JS_EXPORT_PRIVATE JSObject* throwException(ExecState*, JSObject*);
-        
-        void** addressOfJSStackLimit() { return &m_jsStackLimit; }
-        void* jsStackLimit() { return m_jsStackLimit; }
-        void setJSStackLimit(void* limit) { m_jsStackLimit = limit; }
-
-        void* stackLimit() { return m_stackLimit; }
-        void setStackLimit(void* limit) { m_stackLimit = limit; }
-        bool isSafeToRecurse(size_t neededStackInBytes = 0) const
-        {
-            ASSERT(wtfThreadData().stack().isGrowingDownward());
-            int8_t* curr = reinterpret_cast<int8_t*>(&curr);
-            int8_t* limit = reinterpret_cast<int8_t*>(m_stackLimit);
-            return curr >= limit && static_cast<size_t>(curr - limit) >= neededStackInBytes;
-        }
+    void restorePreviousException(Exception* exception) { setException(exception); }
 
-        const ClassInfo* const jsArrayClassInfo;
-        const ClassInfo* const jsFinalObjectClassInfo;
-
-        ReturnAddressPtr exceptionLocation;
-        JSValue hostCallReturnValue;
-        ExecState* newCallFrameReturnValue;
-        ExecState* callFrameForThrow;
-        void* targetMachinePCForThrow;
-        Instruction* targetInterpreterPCForThrow;
-        uint32_t osrExitIndex;
-        void* osrExitJumpDestination;
-        Vector<ScratchBuffer*> scratchBuffers;
-        size_t sizeOfLastScratchBuffer;
-        
-        ScratchBuffer* scratchBufferForSize(size_t size)
-        {
-            if (!size)
-                return 0;
-            
-            if (size > sizeOfLastScratchBuffer) {
-                // Protect against a N^2 memory usage pathology by ensuring
-                // that at worst, we get a geometric series, meaning that the
-                // total memory usage is somewhere around
-                // max(scratch buffer size) * 4.
-                sizeOfLastScratchBuffer = size * 2;
-
-                scratchBuffers.append(ScratchBuffer::create(sizeOfLastScratchBuffer));
-            }
-
-            ScratchBuffer* result = scratchBuffers.last();
-            result->setActiveLength(0);
-            return result;
+    void clearLastException() { m_lastException = nullptr; }
+
+    ExecState** addressOfCallFrameForCatch() { return &callFrameForCatch; }
+
+    JSCell** addressOfException() { return reinterpret_cast<JSCell**>(&m_exception); }
+
+    Exception* lastException() const { return m_lastException; }
+    JSCell** addressOfLastException() { return reinterpret_cast<JSCell**>(&m_lastException); }
+
+    void setFailNextNewCodeBlock() { m_failNextNewCodeBlock = true; }
+    bool getAndClearFailNextNewCodeBlock()
+    {
+        bool result = m_failNextNewCodeBlock;
+        m_failNextNewCodeBlock = false;
+        return result;
+    }
+    
+    ALWAYS_INLINE Structure* getStructure(StructureID id)
+    {
+        return heap.structureIDTable().get(decontaminate(id));
+    }
+    
+    void* stackPointerAtVMEntry() const { return m_stackPointerAtVMEntry; }
+    void setStackPointerAtVMEntry(void*);
+
+    size_t softReservedZoneSize() const { return m_currentSoftReservedZoneSize; }
+    size_t updateSoftReservedZoneSize(size_t softReservedZoneSize);
+    
+    static size_t committedStackByteCount();
+    inline bool ensureStackCapacityFor(Register* newTopOfStack);
+
+    void* stackLimit() { return m_stackLimit; }
+    void* softStackLimit() { return m_softStackLimit; }
+    void** addressOfSoftStackLimit() { return &m_softStackLimit; }
+#if !ENABLE(JIT)
+    void* cloopStackLimit() { return m_cloopStackLimit; }
+    void setCLoopStackLimit(void* limit) { m_cloopStackLimit = limit; }
+#endif
+
+    inline bool isSafeToRecurseSoft() const;
+    bool isSafeToRecurse() const
+    {
+        return isSafeToRecurse(m_stackLimit);
+    }
+
+    void* lastStackTop() { return m_lastStackTop; }
+    void setLastStackTop(void*);
+
+    const ClassInfo* const jsArrayClassInfo;
+    const ClassInfo* const jsFinalObjectClassInfo;
+
+    JSValue hostCallReturnValue;
+    unsigned varargsLength;
+    ExecState* newCallFrameReturnValue;
+    ExecState* callFrameForCatch;
+    void* targetMachinePCForThrow;
+    Instruction* targetInterpreterPCForThrow;
+    uint32_t osrExitIndex;
+    void* osrExitJumpDestination;
+    Vector<ScratchBuffer*> scratchBuffers;
+    size_t sizeOfLastScratchBuffer;
+
+    bool isExecutingInRegExpJIT { false };
+
+    ScratchBuffer* scratchBufferForSize(size_t size)
+    {
+        if (!size)
+            return 0;
+
+        if (size > sizeOfLastScratchBuffer) {
+            // Protect against a N^2 memory usage pathology by ensuring
+            // that at worst, we get a geometric series, meaning that the
+            // total memory usage is somewhere around
+            // max(scratch buffer size) * 4.
+            sizeOfLastScratchBuffer = size * 2;
+
+            ScratchBuffer* newBuffer = ScratchBuffer::create(sizeOfLastScratchBuffer);
+            RELEASE_ASSERT(newBuffer);
+            scratchBuffers.append(newBuffer);
         }
 
-        void gatherConservativeRoots(ConservativeRoots&);
+        ScratchBuffer* result = scratchBuffers.last();
+        result->setActiveLength(0);
+        return result;
+    }
+
+    EncodedJSValue* exceptionFuzzingBuffer(size_t size)
+    {
+        ASSERT(Options::useExceptionFuzz());
+        if (!m_exceptionFuzzBuffer)
+            m_exceptionFuzzBuffer = MallocPtr<EncodedJSValue>::malloc(size);
+        return m_exceptionFuzzBuffer.get();
+    }
 
-        VMEntryScope* entryScope;
+    void gatherConservativeRoots(ConservativeRoots&);
 
-        HashSet<JSObject*> stringRecursionCheckVisitedObjects;
+    VMEntryScope* entryScope;
 
-        LocalTimeOffsetCache localTimeOffsetCache;
-        
-        String cachedDateString;
-        double cachedDateStringValue;
+    JSObject* stringRecursionCheckFirstObject { nullptr };
+    HashSet<JSObject*> stringRecursionCheckVisitedObjects;
 
-        OwnPtr<Profiler::Database> m_perBytecodeProfiler;
-        RefPtr<TypedArrayController> m_typedArrayController;
-        RegExpCache* m_regExpCache;
-        BumpPointerAllocator m_regExpAllocator;
+    LocalTimeOffsetCache localTimeOffsetCache;
+
+    String cachedDateString;
+    double cachedDateStringValue;
+
+    std::unique_ptr<Profiler::Database> m_perBytecodeProfiler;
+    RefPtr<TypedArrayController> m_typedArrayController;
+    RegExpCache* m_regExpCache;
+    BumpPointerAllocator m_regExpAllocator;
+    ConcurrentJSLock m_regExpAllocatorLock;
+
+    std::unique_ptr<HasOwnPropertyCache> m_hasOwnPropertyCache;
+    ALWAYS_INLINE HasOwnPropertyCache* hasOwnPropertyCache() { return m_hasOwnPropertyCache.get(); }
+    HasOwnPropertyCache* ensureHasOwnPropertyCache();
 
 #if ENABLE(REGEXP_TRACING)
-        typedef ListHashSet<RefPtr<RegExp>> RTTraceList;
-        RTTraceList* m_rtTraceList;
+    typedef ListHashSet<RegExp*> RTTraceList;
+    RTTraceList* m_rtTraceList;
 #endif
 
-        ThreadIdentifier exclusiveThread;
+    bool hasExclusiveThread() const { return m_apiLock->hasExclusiveThread(); }
+    std::thread::id exclusiveThread() const { return m_apiLock->exclusiveThread(); }
+    void setExclusiveThread(std::thread::id threadId) { m_apiLock->setExclusiveThread(threadId); }
 
-        JS_EXPORT_PRIVATE void resetDateCache();
+    JS_EXPORT_PRIVATE void resetDateCache();
 
-        JS_EXPORT_PRIVATE void startSampling();
-        JS_EXPORT_PRIVATE void stopSampling();
-        JS_EXPORT_PRIVATE void dumpSampleData(ExecState* exec);
-        RegExpCache* regExpCache() { return m_regExpCache; }
+    RegExpCache* regExpCache() { return m_regExpCache; }
 #if ENABLE(REGEXP_TRACING)
-        void addRegExpToTrace(PassRefPtr<RegExp> regExp);
+    void addRegExpToTrace(RegExp*);
 #endif
-        JS_EXPORT_PRIVATE void dumpRegExpTrace();
+    JS_EXPORT_PRIVATE void dumpRegExpTrace();
 
-        bool isCollectorBusy() { return heap.isBusy(); }
-        JS_EXPORT_PRIVATE void releaseExecutableMemory();
+    bool isCollectorBusyOnCurrentThread() { return heap.isCurrentThreadBusy(); }
 
 #if ENABLE(GC_VALIDATION)
-        bool isInitializingObject() const; 
-        void setInitializingObjectClass(const ClassInfo*);
+    bool isInitializingObject() const; 
+    void setInitializingObjectClass(const ClassInfo*);
 #endif
 
-        unsigned m_newStringsSinceLastHashCons;
+    bool currentThreadIsHoldingAPILock() const { return m_apiLock->currentThreadIsHoldingLock(); }
 
-        static const unsigned s_minNumberOfNewStringsToHashCons = 100;
+    JSLock& apiLock() { return *m_apiLock; }
+    CodeCache* codeCache() { return m_codeCache.get(); }
 
-        bool haveEnoughNewStringsToHashCons() { return m_newStringsSinceLastHashCons > s_minNumberOfNewStringsToHashCons; }
-        void resetNewStringsSinceLastHashCons() { m_newStringsSinceLastHashCons = 0; }
+    JS_EXPORT_PRIVATE void whenIdle(std::function<void()>);
 
-        bool currentThreadIsHoldingAPILock() const
-        {
-            return m_apiLock->currentThreadIsHoldingLock() || exclusiveThread == currentThread();
-        }
+    JS_EXPORT_PRIVATE void deleteAllCode(DeleteAllCodeEffort);
+    JS_EXPORT_PRIVATE void deleteAllLinkedCode(DeleteAllCodeEffort);
 
-        JSLock& apiLock() { return *m_apiLock; }
-        CodeCache* codeCache() { return m_codeCache.get(); }
+    WatchpointSet* ensureWatchpointSetForImpureProperty(const Identifier&);
+    void registerWatchpointForImpureProperty(const Identifier&, Watchpoint*);
+    
+    // FIXME: Use AtomicString once it got merged with Identifier.
+    JS_EXPORT_PRIVATE void addImpureProperty(const String&);
 
-        void prepareToDiscardCode();
-        
-        JS_EXPORT_PRIVATE void discardAllCode();
+    BuiltinExecutables* builtinExecutables() { return m_builtinExecutables.get(); }
 
-        void registerWatchpointForImpureProperty(const Identifier&, Watchpoint*);
-        // FIXME: Use AtomicString once it got merged with Identifier.
-        JS_EXPORT_PRIVATE void addImpureProperty(const String&);
+    bool enableTypeProfiler();
+    bool disableTypeProfiler();
+    TypeProfilerLog* typeProfilerLog() { return m_typeProfilerLog.get(); }
+    TypeProfiler* typeProfiler() { return m_typeProfiler.get(); }
+    JS_EXPORT_PRIVATE void dumpTypeProfilerData();
+
+    FunctionHasExecutedCache* functionHasExecutedCache() { return &m_functionHasExecutedCache; }
+
+    ControlFlowProfiler* controlFlowProfiler() { return m_controlFlowProfiler.get(); }
+    bool enableControlFlowProfiler();
+    bool disableControlFlowProfiler();
+
+    JS_EXPORT_PRIVATE void queueMicrotask(JSGlobalObject*, Ref<Microtask>&&);
+    JS_EXPORT_PRIVATE void drainMicrotasks();
+    void setGlobalConstRedeclarationShouldThrow(bool globalConstRedeclarationThrow) { m_globalConstRedeclarationShouldThrow = globalConstRedeclarationThrow; }
+    ALWAYS_INLINE bool globalConstRedeclarationShouldThrow() const { return m_globalConstRedeclarationShouldThrow; }
+
+    inline bool shouldTriggerTermination(ExecState*);
+
+    void setShouldBuildPCToCodeOriginMapping() { m_shouldBuildPCToCodeOriginMapping = true; }
+    bool shouldBuilderPCToCodeOriginMapping() const { return m_shouldBuildPCToCodeOriginMapping; }
+
+    BytecodeIntrinsicRegistry& bytecodeIntrinsicRegistry() { return *m_bytecodeIntrinsicRegistry; }
+    
+    ShadowChicken& shadowChicken() { return *m_shadowChicken; }
+    
+    template<typename Func>
+    void logEvent(CodeBlock*, const char* summary, const Func& func);
+
+private:
+    friend class LLIntOffsetsExtractor;
+
+    VM(VMType, HeapType);
+    static VM*& sharedInstanceInternal();
+    void createNativeThunk();
+
+    void updateStackLimits();
+
+    bool isSafeToRecurse(void* stackLimit) const
+    {
+        ASSERT(wtfThreadData().stack().isGrowingDownward());
+        void* curr = reinterpret_cast<void*>(&curr);
+        return curr >= stackLimit;
+    }
+
+    void setException(Exception* exception)
+    {
+        m_exception = exception;
+        m_lastException = exception;
+    }
+    Exception* exception() const
+    {
+#if ENABLE(EXCEPTION_SCOPE_VERIFICATION)
+        m_needExceptionCheck = false;
+#endif
+        return m_exception;
+    }
+    void clearException()
+    {
+#if ENABLE(EXCEPTION_SCOPE_VERIFICATION)
+        m_needExceptionCheck = false;
+#endif
+        m_exception = nullptr;
+    }
+
+#if !ENABLE(JIT)    
+    bool ensureStackCapacityForCLoop(Register* newTopOfStack);
+    bool isSafeToRecurseSoftCLoop() const;
+#endif // !ENABLE(JIT)
+
+    JS_EXPORT_PRIVATE void throwException(ExecState*, Exception*);
+    JS_EXPORT_PRIVATE JSValue throwException(ExecState*, JSValue);
+    JS_EXPORT_PRIVATE JSObject* throwException(ExecState*, JSObject*);
+
+#if ENABLE(EXCEPTION_SCOPE_VERIFICATION)
+    void verifyExceptionCheckNeedIsSatisfied(unsigned depth, ExceptionEventLocation&);
+#endif
 
-    private:
-        friend class LLIntOffsetsExtractor;
-        friend class ClearExceptionScope;
-        friend class RecursiveAllocationScope;
-        
-        VM(VMType, HeapType);
-        static VM*& sharedInstanceInternal();
-        void createNativeThunk();
 #if ENABLE(ASSEMBLER)
-        bool m_canUseAssembler;
+    bool m_canUseAssembler;
 #endif
 #if ENABLE(JIT)
-        bool m_canUseJIT;
+    bool m_canUseJIT;
 #endif
 #if ENABLE(YARR_JIT)
-        bool m_canUseRegExpJIT;
+    bool m_canUseRegExpJIT;
 #endif
 #if ENABLE(GC_VALIDATION)
-        const ClassInfo* m_initializingObjectClass;
+    const ClassInfo* m_initializingObjectClass;
 #endif
 
-#if USE(SEPARATE_C_AND_JS_STACK)
-        struct {
-            void* m_stackLimit;
-            void* m_jsStackLimit;
-        };
-#else
-        union {
-            void* m_stackLimit;
-            void* m_jsStackLimit;
-        };
+    void* m_stackPointerAtVMEntry;
+    size_t m_currentSoftReservedZoneSize;
+    void* m_stackLimit { nullptr };
+    void* m_softStackLimit { nullptr };
+#if !ENABLE(JIT)
+    void* m_cloopStackLimit { nullptr };
+#endif
+    void* m_lastStackTop;
+
+    Exception* m_exception { nullptr };
+    Exception* m_lastException { nullptr };
+#if ENABLE(EXCEPTION_SCOPE_VERIFICATION)
+    ExceptionScope* m_topExceptionScope { nullptr };
+    ExceptionEventLocation m_simulatedThrowPointLocation;
+    unsigned m_simulatedThrowPointRecursionDepth { 0 };
+    mutable bool m_needExceptionCheck { false };
 #endif
-        JSValue m_exception;
-        bool m_inDefineOwnProperty;
-        OwnPtr<CodeCache> m_codeCache;
-        RefCountedArray<StackFrame> m_exceptionStack;
 
-        LegacyProfiler* m_enabledProfiler;
+    bool m_failNextNewCodeBlock { false };
+    DeletePropertyMode m_deletePropertyMode { DeletePropertyMode::Default };
+    bool m_globalConstRedeclarationShouldThrow { true };
+    bool m_shouldBuildPCToCodeOriginMapping { false };
+    std::unique_ptr<CodeCache> m_codeCache;
+    std::unique_ptr<BuiltinExecutables> m_builtinExecutables;
+    HashMap<String, RefPtr<WatchpointSet>> m_impurePropertyWatchpointSets;
+    std::unique_ptr<TypeProfiler> m_typeProfiler;
+    std::unique_ptr<TypeProfilerLog> m_typeProfilerLog;
+    unsigned m_typeProfilerEnabledCount;
+    FunctionHasExecutedCache m_functionHasExecutedCache;
+    std::unique_ptr<ControlFlowProfiler> m_controlFlowProfiler;
+    unsigned m_controlFlowProfilerEnabledCount;
+    Deque<std::unique_ptr<QueuedTask>> m_microtaskQueue;
+    MallocPtr<EncodedJSValue> m_exceptionFuzzBuffer;
+    RefPtr<Watchdog> m_watchdog;
+    std::unique_ptr<HeapProfiler> m_heapProfiler;
+#if ENABLE(SAMPLING_PROFILER)
+    RefPtr<SamplingProfiler> m_samplingProfiler;
+#endif
+    std::unique_ptr<ShadowChicken> m_shadowChicken;
+    std::unique_ptr<BytecodeIntrinsicRegistry> m_bytecodeIntrinsicRegistry;
 
-        HashMap<String, RefPtr<WatchpointSet>> m_impurePropertyWatchpointSets;
-    };
+    VM* m_prev; // Required by DoublyLinkedListNode.
+    VM* m_next; // Required by DoublyLinkedListNode.
+
+    // Friends for exception checking purpose only.
+    friend class Heap;
+    friend class CatchScope;
+    friend class ExceptionScope;
+    friend class ThrowScope;
+    friend class WTF::DoublyLinkedListNode<VM>;
+};
 
 #if ENABLE(GC_VALIDATION)
-    inline bool VM::isInitializingObject() const
-    {
-        return !!m_initializingObjectClass;
-    }
+inline bool VM::isInitializingObject() const
+{
+    return !!m_initializingObjectClass;
+}
+
+inline void VM::setInitializingObjectClass(const ClassInfo* initializingObjectClass)
+{
+    m_initializingObjectClass = initializingObjectClass;
+}
+#endif
 
-    inline void VM::setInitializingObjectClass(const ClassInfo* initializingObjectClass)
-    {
-        m_initializingObjectClass = initializingObjectClass;
-    }
+inline Heap* WeakSet::heap() const
+{
+    return &m_vm->heap;
+}
+
+#if ENABLE(JIT)
+extern "C" void sanitizeStackForVMImpl(VM*);
 #endif
 
-    inline Heap* WeakSet::heap() const
-    {
-        return &m_vm->heap;
-    }
+void sanitizeStackForVM(VM*);
+void logSanitizeStack(VM*);
 
 } // namespace JSC
-
-#endif // VM_h