Source/JavaScriptCore/runtime/Structure.h - platform/external/webkit - Git at Google

 /*
  * Copyright (C) 2008, 2009 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 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.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``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 APPLE COMPUTER, INC. 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 Structure_h
 #define Structure_h

 #include "Identifier.h"
 #include "JSCell.h"
 #include "JSType.h"
 #include "JSValue.h"
 #include "PropertyMapHashTable.h"
 #include "PropertyNameArray.h"
 #include "Protect.h"
 #include "StructureTransitionTable.h"
 #include "JSTypeInfo.h"
 #include "UString.h"
 #include "Weak.h"
 #include <wtf/PassRefPtr.h>
 #include <wtf/RefCounted.h>


 namespace JSC {

     class MarkStack;
     class PropertyNameArray;
     class PropertyNameArrayData;
     class StructureChain;

     struct ClassInfo;

     enum EnumerationMode {
         ExcludeDontEnumProperties,
         IncludeDontEnumProperties
     };

     class Structure : public JSCell {
     public:
         friend class StructureTransitionTable;
         static Structure* create(JSGlobalData& globalData, JSValue prototype, const TypeInfo& typeInfo, unsigned anonymousSlotCount, const ClassInfo* classInfo)
         {
             ASSERT(globalData.structureStructure);
             return new (&globalData) Structure(globalData, prototype, typeInfo, anonymousSlotCount, classInfo);
         }

         static void dumpStatistics();

         static Structure* addPropertyTransition(JSGlobalData&, Structure*, const Identifier& propertyName, unsigned attributes, JSCell* specificValue, size_t& offset);
         static Structure* addPropertyTransitionToExistingStructure(Structure*, const Identifier& propertyName, unsigned attributes, JSCell* specificValue, size_t& offset);
         static Structure* removePropertyTransition(JSGlobalData&, Structure*, const Identifier& propertyName, size_t& offset);
         static Structure* changePrototypeTransition(JSGlobalData&, Structure*, JSValue prototype);
         static Structure* despecifyFunctionTransition(JSGlobalData&, Structure*, const Identifier&);
         static Structure* getterSetterTransition(JSGlobalData&, Structure*);
         static Structure* toCacheableDictionaryTransition(JSGlobalData&, Structure*);
         static Structure* toUncacheableDictionaryTransition(JSGlobalData&, Structure*);
         static Structure* sealTransition(JSGlobalData&, Structure*);
         static Structure* freezeTransition(JSGlobalData&, Structure*);
         static Structure* preventExtensionsTransition(JSGlobalData&, Structure*);

         bool isSealed(JSGlobalData&);
         bool isFrozen(JSGlobalData&);
         bool isExtensible() const { return !m_preventExtensions; }

         Structure* flattenDictionaryStructure(JSGlobalData&, JSObject*);

         ~Structure();

         // These should be used with caution.
         size_t addPropertyWithoutTransition(JSGlobalData&, const Identifier& propertyName, unsigned attributes, JSCell* specificValue);
         size_t removePropertyWithoutTransition(JSGlobalData&, const Identifier& propertyName);
         void setPrototypeWithoutTransition(JSGlobalData& globalData, JSValue prototype) { m_prototype.set(globalData, this, prototype); }

         bool isDictionary() const { return m_dictionaryKind != NoneDictionaryKind; }
         bool isUncacheableDictionary() const { return m_dictionaryKind == UncachedDictionaryKind; }

         const TypeInfo& typeInfo() const { return m_typeInfo; }

         JSValue storedPrototype() const { return m_prototype.get(); }
         JSValue prototypeForLookup(ExecState*) const;
         StructureChain* prototypeChain(ExecState*) const;
         void markChildren(MarkStack&);

         Structure* previousID() const { return m_previous.get(); }

         void growPropertyStorageCapacity();
         unsigned propertyStorageCapacity() const { return m_propertyStorageCapacity; }
         unsigned propertyStorageSize() const { return m_anonymousSlotCount + (m_propertyTable ? m_propertyTable->propertyStorageSize() : static_cast<unsigned>(m_offset + 1)); }
         bool isUsingInlineStorage() const;

         size_t get(JSGlobalData&, const Identifier& propertyName);
         size_t get(JSGlobalData&, StringImpl* propertyName, unsigned& attributes, JSCell*& specificValue);
         size_t get(JSGlobalData& globalData, const Identifier& propertyName, unsigned& attributes, JSCell*& specificValue)
         {
             ASSERT(!propertyName.isNull());
             return get(globalData, propertyName.impl(), attributes, specificValue);
         }

         bool hasGetterSetterProperties() const { return m_hasGetterSetterProperties; }
         void setHasGetterSetterProperties(bool hasGetterSetterProperties) { m_hasGetterSetterProperties = hasGetterSetterProperties; }

         bool hasNonEnumerableProperties() const { return m_hasNonEnumerableProperties; }

         bool hasAnonymousSlots() const { return !!m_anonymousSlotCount; }
         unsigned anonymousSlotCount() const { return m_anonymousSlotCount; }

         bool isEmpty() const { return m_propertyTable ? m_propertyTable->isEmpty() : m_offset == noOffset; }

         void despecifyDictionaryFunction(JSGlobalData&, const Identifier& propertyName);
         void disableSpecificFunctionTracking() { m_specificFunctionThrashCount = maxSpecificFunctionThrashCount; }

         void setEnumerationCache(JSGlobalData&, JSPropertyNameIterator* enumerationCache); // Defined in JSPropertyNameIterator.h.
         JSPropertyNameIterator* enumerationCache(); // Defined in JSPropertyNameIterator.h.
         void getPropertyNames(JSGlobalData&, PropertyNameArray&, EnumerationMode mode);

         const ClassInfo* classInfo() const { return m_classInfo; }

         static ptrdiff_t prototypeOffset()
         {
             return OBJECT_OFFSETOF(Structure, m_prototype);
         }

         static ptrdiff_t typeInfoFlagsOffset()
         {
             return OBJECT_OFFSETOF(Structure, m_typeInfo) + TypeInfo::flagsOffset();
         }

         static ptrdiff_t typeInfoTypeOffset()
         {
             return OBJECT_OFFSETOF(Structure, m_typeInfo) + TypeInfo::typeOffset();
         }

         static Structure* createStructure(JSGlobalData& globalData)
         {
             ASSERT(!globalData.structureStructure);
             return new (&globalData) Structure(globalData);
         }

     private:
         Structure(JSGlobalData&, JSValue prototype, const TypeInfo&, unsigned anonymousSlotCount, const ClassInfo*);
         Structure(JSGlobalData&);
         Structure(JSGlobalData&, const Structure*);

         static Structure* create(JSGlobalData& globalData, const Structure* structure)
         {
             ASSERT(globalData.structureStructure);
             return new (&globalData) Structure(globalData, structure);
         }

         static const ClassInfo s_info;

         typedef enum {
             NoneDictionaryKind = 0,
             CachedDictionaryKind = 1,
             UncachedDictionaryKind = 2
         } DictionaryKind;
         static Structure* toDictionaryTransition(JSGlobalData&, Structure*, DictionaryKind);

         size_t putSpecificValue(JSGlobalData&, const Identifier& propertyName, unsigned attributes, JSCell* specificValue);
         size_t remove(const Identifier& propertyName);

         void createPropertyMap(unsigned keyCount = 0);
         void checkConsistency();

         bool despecifyFunction(JSGlobalData&, const Identifier&);
         void despecifyAllFunctions(JSGlobalData&);

         PropertyTable* copyPropertyTable(JSGlobalData&, Structure* owner);
         void materializePropertyMap(JSGlobalData&);
         void materializePropertyMapIfNecessary(JSGlobalData& globalData)
         {
             if (!m_propertyTable && m_previous)
                 materializePropertyMap(globalData);
         }

         signed char transitionCount() const
         {
             // Since the number of transitions is always the same as m_offset, we keep the size of Structure down by not storing both.
             return m_offset == noOffset ? 0 : m_offset + 1;
         }

         bool isValid(ExecState*, StructureChain* cachedPrototypeChain) const;

         static const signed char s_maxTransitionLength = 64;

         static const signed char noOffset = -1;

         static const unsigned maxSpecificFunctionThrashCount = 3;

         TypeInfo m_typeInfo;

         WriteBarrier<Unknown> m_prototype;
         mutable WriteBarrier<StructureChain> m_cachedPrototypeChain;

         WriteBarrier<Structure> m_previous;
         RefPtr<StringImpl> m_nameInPrevious;
         WriteBarrier<JSCell> m_specificValueInPrevious;

         const ClassInfo* m_classInfo;

         StructureTransitionTable m_transitionTable;

         WriteBarrier<JSPropertyNameIterator> m_enumerationCache;

         OwnPtr<PropertyTable> m_propertyTable;

         uint32_t m_propertyStorageCapacity;

         // m_offset does not account for anonymous slots
         signed char m_offset;

         unsigned m_dictionaryKind : 2;
         bool m_isPinnedPropertyTable : 1;
         bool m_hasGetterSetterProperties : 1;
         bool m_hasNonEnumerableProperties : 1;
 #if COMPILER(WINSCW)
         // Workaround for Symbian WINSCW compiler that cannot resolve unsigned type of the declared
         // bitfield, when used as argument in make_pair() function calls in structure.ccp.
         // This bitfield optimization is insignificant for the Symbian emulator target.
         unsigned m_attributesInPrevious;
 #else
         unsigned m_attributesInPrevious : 7;
 #endif
         unsigned m_specificFunctionThrashCount : 2;
         unsigned m_anonymousSlotCount : 5;
         unsigned m_preventExtensions : 1;
         // 4 free bits
     };

     inline size_t Structure::get(JSGlobalData& globalData, const Identifier& propertyName)
     {
         materializePropertyMapIfNecessary(globalData);
         if (!m_propertyTable)
             return notFound;

         PropertyMapEntry* entry = m_propertyTable->find(propertyName.impl()).first;
         ASSERT(!entry || entry->offset >= m_anonymousSlotCount);
         return entry ? entry->offset : notFound;
     }

     inline bool JSCell::isObject() const
     {
         return m_structure->typeInfo().type() == ObjectType;
     }

     inline bool JSCell::isString() const
     {
         return m_structure->typeInfo().type() == StringType;
     }

     inline const ClassInfo* JSCell::classInfo() const
     {
         return m_structure->classInfo();
     }

     inline Structure* JSCell::createDummyStructure(JSGlobalData& globalData)
     {
         return Structure::create(globalData, jsNull(), TypeInfo(UnspecifiedType), AnonymousSlotCount, 0);
     }

     inline bool JSValue::needsThisConversion() const
     {
         if (UNLIKELY(!isCell()))
             return true;
         return asCell()->structure()->typeInfo().needsThisConversion();
     }

     ALWAYS_INLINE void MarkStack::internalAppend(JSCell* cell)
     {
         ASSERT(!m_isCheckingForDefaultMarkViolation);
         ASSERT(cell);
         if (Heap::testAndSetMarked(cell))
             return;
         if (cell->structure()->typeInfo().type() >= CompoundType)
             m_values.append(cell);
     }

     inline StructureTransitionTable::Hash::Key StructureTransitionTable::keyForWeakGCMapFinalizer(void*, Structure* structure)
     {
         return Hash::Key(structure->m_nameInPrevious.get(), structure->m_attributesInPrevious);
     }

 } // namespace JSC

 #endif // Structure_h
	/*
	* Copyright (C) 2008, 2009 Apple 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:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 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.
	*
	* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``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 APPLE COMPUTER, INC. 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 Structure_h
	#define Structure_h

	#include "Identifier.h"
	#include "JSCell.h"
	#include "JSType.h"
	#include "JSValue.h"
	#include "PropertyMapHashTable.h"
	#include "PropertyNameArray.h"
	#include "Protect.h"
	#include "StructureTransitionTable.h"
	#include "JSTypeInfo.h"
	#include "UString.h"
	#include "Weak.h"
	#include <wtf/PassRefPtr.h>
	#include <wtf/RefCounted.h>


	namespace JSC {

	class MarkStack;
	class PropertyNameArray;
	class PropertyNameArrayData;
	class StructureChain;

	struct ClassInfo;

	enum EnumerationMode {
	ExcludeDontEnumProperties,
	IncludeDontEnumProperties
	};

	class Structure : public JSCell {
	public:
	friend class StructureTransitionTable;
	static Structure* create(JSGlobalData& globalData, JSValue prototype, const TypeInfo& typeInfo, unsigned anonymousSlotCount, const ClassInfo* classInfo)
	{
	ASSERT(globalData.structureStructure);
	return new (&globalData) Structure(globalData, prototype, typeInfo, anonymousSlotCount, classInfo);
	}

	static void dumpStatistics();

	static Structure* addPropertyTransition(JSGlobalData&, Structure, const Identifier& propertyName, unsigned attributes, JSCell specificValue, size_t& offset);
	static Structure* addPropertyTransitionToExistingStructure(Structure, const Identifier& propertyName, unsigned attributes, JSCell specificValue, size_t& offset);
	static Structure* removePropertyTransition(JSGlobalData&, Structure*, const Identifier& propertyName, size_t& offset);
	static Structure* changePrototypeTransition(JSGlobalData&, Structure*, JSValue prototype);
	static Structure* despecifyFunctionTransition(JSGlobalData&, Structure*, const Identifier&);
	static Structure* getterSetterTransition(JSGlobalData&, Structure*);
	static Structure* toCacheableDictionaryTransition(JSGlobalData&, Structure*);
	static Structure* toUncacheableDictionaryTransition(JSGlobalData&, Structure*);
	static Structure* sealTransition(JSGlobalData&, Structure*);
	static Structure* freezeTransition(JSGlobalData&, Structure*);
	static Structure* preventExtensionsTransition(JSGlobalData&, Structure*);

	bool isSealed(JSGlobalData&);
	bool isFrozen(JSGlobalData&);
	bool isExtensible() const { return !m_preventExtensions; }

	Structure* flattenDictionaryStructure(JSGlobalData&, JSObject*);

	~Structure();

	// These should be used with caution.
	size_t addPropertyWithoutTransition(JSGlobalData&, const Identifier& propertyName, unsigned attributes, JSCell* specificValue);
	size_t removePropertyWithoutTransition(JSGlobalData&, const Identifier& propertyName);
	void setPrototypeWithoutTransition(JSGlobalData& globalData, JSValue prototype) { m_prototype.set(globalData, this, prototype); }

	bool isDictionary() const { return m_dictionaryKind != NoneDictionaryKind; }
	bool isUncacheableDictionary() const { return m_dictionaryKind == UncachedDictionaryKind; }

	const TypeInfo& typeInfo() const { return m_typeInfo; }

	JSValue storedPrototype() const { return m_prototype.get(); }
	JSValue prototypeForLookup(ExecState*) const;
	StructureChain* prototypeChain(ExecState*) const;
	void markChildren(MarkStack&);

	Structure* previousID() const { return m_previous.get(); }

	void growPropertyStorageCapacity();
	unsigned propertyStorageCapacity() const { return m_propertyStorageCapacity; }
	unsigned propertyStorageSize() const { return m_anonymousSlotCount + (m_propertyTable ? m_propertyTable->propertyStorageSize() : static_cast<unsigned>(m_offset + 1)); }
	bool isUsingInlineStorage() const;

	size_t get(JSGlobalData&, const Identifier& propertyName);
	size_t get(JSGlobalData&, StringImpl* propertyName, unsigned& attributes, JSCell*& specificValue);
	size_t get(JSGlobalData& globalData, const Identifier& propertyName, unsigned& attributes, JSCell*& specificValue)
	{
	ASSERT(!propertyName.isNull());
	return get(globalData, propertyName.impl(), attributes, specificValue);
	}

	bool hasGetterSetterProperties() const { return m_hasGetterSetterProperties; }
	void setHasGetterSetterProperties(bool hasGetterSetterProperties) { m_hasGetterSetterProperties = hasGetterSetterProperties; }

	bool hasNonEnumerableProperties() const { return m_hasNonEnumerableProperties; }

	bool hasAnonymousSlots() const { return !!m_anonymousSlotCount; }
	unsigned anonymousSlotCount() const { return m_anonymousSlotCount; }

	bool isEmpty() const { return m_propertyTable ? m_propertyTable->isEmpty() : m_offset == noOffset; }

	void despecifyDictionaryFunction(JSGlobalData&, const Identifier& propertyName);
	void disableSpecificFunctionTracking() { m_specificFunctionThrashCount = maxSpecificFunctionThrashCount; }

	void setEnumerationCache(JSGlobalData&, JSPropertyNameIterator* enumerationCache); // Defined in JSPropertyNameIterator.h.
	JSPropertyNameIterator* enumerationCache(); // Defined in JSPropertyNameIterator.h.
	void getPropertyNames(JSGlobalData&, PropertyNameArray&, EnumerationMode mode);

	const ClassInfo* classInfo() const { return m_classInfo; }

	static ptrdiff_t prototypeOffset()
	{
	return OBJECT_OFFSETOF(Structure, m_prototype);
	}

	static ptrdiff_t typeInfoFlagsOffset()
	{
	return OBJECT_OFFSETOF(Structure, m_typeInfo) + TypeInfo::flagsOffset();
	}

	static ptrdiff_t typeInfoTypeOffset()
	{
	return OBJECT_OFFSETOF(Structure, m_typeInfo) + TypeInfo::typeOffset();
	}

	static Structure* createStructure(JSGlobalData& globalData)
	{
	ASSERT(!globalData.structureStructure);
	return new (&globalData) Structure(globalData);
	}

	private:
	Structure(JSGlobalData&, JSValue prototype, const TypeInfo&, unsigned anonymousSlotCount, const ClassInfo*);
	Structure(JSGlobalData&);
	Structure(JSGlobalData&, const Structure*);

	static Structure* create(JSGlobalData& globalData, const Structure* structure)
	{
	ASSERT(globalData.structureStructure);
	return new (&globalData) Structure(globalData, structure);
	}

	static const ClassInfo s_info;

	typedef enum {
	NoneDictionaryKind = 0,
	CachedDictionaryKind = 1,
	UncachedDictionaryKind = 2
	} DictionaryKind;
	static Structure* toDictionaryTransition(JSGlobalData&, Structure*, DictionaryKind);

	size_t putSpecificValue(JSGlobalData&, const Identifier& propertyName, unsigned attributes, JSCell* specificValue);
	size_t remove(const Identifier& propertyName);

	void createPropertyMap(unsigned keyCount = 0);
	void checkConsistency();

	bool despecifyFunction(JSGlobalData&, const Identifier&);
	void despecifyAllFunctions(JSGlobalData&);

	PropertyTable* copyPropertyTable(JSGlobalData&, Structure* owner);
	void materializePropertyMap(JSGlobalData&);
	void materializePropertyMapIfNecessary(JSGlobalData& globalData)
	{
	if (!m_propertyTable && m_previous)
	materializePropertyMap(globalData);
	}

	signed char transitionCount() const
	{
	// Since the number of transitions is always the same as m_offset, we keep the size of Structure down by not storing both.
	return m_offset == noOffset ? 0 : m_offset + 1;
	}

	bool isValid(ExecState, StructureChain cachedPrototypeChain) const;

	static const signed char s_maxTransitionLength = 64;

	static const signed char noOffset = -1;

	static const unsigned maxSpecificFunctionThrashCount = 3;

	TypeInfo m_typeInfo;

	WriteBarrier<Unknown> m_prototype;
	mutable WriteBarrier<StructureChain> m_cachedPrototypeChain;

	WriteBarrier<Structure> m_previous;
	RefPtr<StringImpl> m_nameInPrevious;
	WriteBarrier<JSCell> m_specificValueInPrevious;

	const ClassInfo* m_classInfo;

	StructureTransitionTable m_transitionTable;

	WriteBarrier<JSPropertyNameIterator> m_enumerationCache;

	OwnPtr<PropertyTable> m_propertyTable;

	uint32_t m_propertyStorageCapacity;

	// m_offset does not account for anonymous slots
	signed char m_offset;

	unsigned m_dictionaryKind : 2;
	bool m_isPinnedPropertyTable : 1;
	bool m_hasGetterSetterProperties : 1;
	bool m_hasNonEnumerableProperties : 1;
	#if COMPILER(WINSCW)
	// Workaround for Symbian WINSCW compiler that cannot resolve unsigned type of the declared
	// bitfield, when used as argument in make_pair() function calls in structure.ccp.
	// This bitfield optimization is insignificant for the Symbian emulator target.
	unsigned m_attributesInPrevious;
	#else
	unsigned m_attributesInPrevious : 7;
	#endif
	unsigned m_specificFunctionThrashCount : 2;
	unsigned m_anonymousSlotCount : 5;
	unsigned m_preventExtensions : 1;
	// 4 free bits
	};

	inline size_t Structure::get(JSGlobalData& globalData, const Identifier& propertyName)
	{
	materializePropertyMapIfNecessary(globalData);
	if (!m_propertyTable)
	return notFound;

	PropertyMapEntry* entry = m_propertyTable->find(propertyName.impl()).first;
	ASSERT(!entry \|\| entry->offset >= m_anonymousSlotCount);
	return entry ? entry->offset : notFound;
	}

	inline bool JSCell::isObject() const
	{
	return m_structure->typeInfo().type() == ObjectType;
	}

	inline bool JSCell::isString() const
	{
	return m_structure->typeInfo().type() == StringType;
	}

	inline const ClassInfo* JSCell::classInfo() const
	{
	return m_structure->classInfo();
	}

	inline Structure* JSCell::createDummyStructure(JSGlobalData& globalData)
	{
	return Structure::create(globalData, jsNull(), TypeInfo(UnspecifiedType), AnonymousSlotCount, 0);
	}

	inline bool JSValue::needsThisConversion() const
	{
	if (UNLIKELY(!isCell()))
	return true;
	return asCell()->structure()->typeInfo().needsThisConversion();
	}

	ALWAYS_INLINE void MarkStack::internalAppend(JSCell* cell)
	{
	ASSERT(!m_isCheckingForDefaultMarkViolation);
	ASSERT(cell);
	if (Heap::testAndSetMarked(cell))
	return;
	if (cell->structure()->typeInfo().type() >= CompoundType)
	m_values.append(cell);
	}

	inline StructureTransitionTable::Hash::Key StructureTransitionTable::keyForWeakGCMapFinalizer(void, Structure structure)
	{
	return Hash::Key(structure->m_nameInPrevious.get(), structure->m_attributesInPrevious);
	}

	} // namespace JSC

	#endif // Structure_h