auto import from //depot/cupcake/@135843

1 files changed, 216 insertions, 0 deletions

diff --git a/JavaScriptCore/runtime/StructureID.h b/JavaScriptCore/runtime/StructureID.h
new file mode 100644
index 0000000..4f45dac
--- /dev/null
+++ b/JavaScriptCore/runtime/StructureID.h
@@ -0,0 +1,216 @@
+/*
+ * Copyright (C) 2008 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 StructureID_h
+#define StructureID_h
+
+#include "JSType.h"
+#include "JSValue.h"
+#include "PropertyMapHashTable.h"
+#include "StructureIDChain.h"
+#include "StructureIDTransitionTable.h"
+#include "TypeInfo.h"
+#include "identifier.h"
+#include "ustring.h"
+#include <wtf/HashFunctions.h>
+#include <wtf/HashTraits.h>
+#include <wtf/OwnArrayPtr.h>
+#include <wtf/PassRefPtr.h>
+#include <wtf/RefCounted.h>
+
+#ifndef NDEBUG
+#define DUMP_PROPERTYMAP_STATS 0
+#else
+#define DUMP_PROPERTYMAP_STATS 0
+#endif
+
+namespace JSC {
+
+    class PropertyNameArray;
+    class PropertyNameArrayData;
+
+    class StructureID : public RefCounted<StructureID> {
+    public:
+        friend class CTI;
+        static PassRefPtr<StructureID> create(JSValue* prototype, const TypeInfo& typeInfo)
+        {
+            return adoptRef(new StructureID(prototype, typeInfo));
+        }
+
+        static void startIgnoringLeaks();
+        static void stopIgnoringLeaks();
+
+        static void dumpStatistics();
+
+        static PassRefPtr<StructureID> changePrototypeTransition(StructureID*, JSValue* prototype);
+        static PassRefPtr<StructureID> addPropertyTransition(StructureID*, const Identifier& propertyName, unsigned attributes, size_t& offset);
+        static PassRefPtr<StructureID> removePropertyTransition(StructureID*, const Identifier& propertyName, size_t& offset);
+        static PassRefPtr<StructureID> getterSetterTransition(StructureID*);
+        static PassRefPtr<StructureID> toDictionaryTransition(StructureID*);
+        static PassRefPtr<StructureID> fromDictionaryTransition(StructureID*);
+
+        ~StructureID();
+
+        void mark()
+        {
+            if (!m_prototype->marked())
+                m_prototype->mark();
+        }
+
+        // These should be used with caution.  
+        size_t addPropertyWithoutTransition(const Identifier& propertyName, unsigned attributes);
+        size_t removePropertyWithoutTransition(const Identifier& propertyName);
+        void setPrototypeWithoutTransition(JSValue* prototype) { m_prototype = prototype; }
+
+        bool isDictionary() const { return m_isDictionary; }
+
+        const TypeInfo& typeInfo() const { return m_typeInfo; }
+
+        // For use when first creating a new structure.
+        TypeInfo& mutableTypeInfo() { return m_typeInfo; }
+
+        JSValue* storedPrototype() const { return m_prototype; }
+        JSValue* prototypeForLookup(ExecState*); 
+
+        StructureID* previousID() const { return m_previous.get(); }
+
+        StructureIDChain* createCachedPrototypeChain();
+        void setCachedPrototypeChain(PassRefPtr<StructureIDChain> cachedPrototypeChain) { m_cachedPrototypeChain = cachedPrototypeChain; }
+        StructureIDChain* cachedPrototypeChain() const { return m_cachedPrototypeChain.get(); }
+
+        void setCachedTransistionOffset(size_t offset) { m_cachedTransistionOffset = offset; }
+        size_t cachedTransistionOffset() const { return m_cachedTransistionOffset; }
+
+        void growPropertyStorageCapacity();
+        size_t propertyStorageCapacity() const { return m_propertyStorageCapacity; }
+        size_t propertyStorageSize() const { return m_propertyTable ? m_propertyTable->keyCount + m_deletedOffsets.size() : 0; }
+
+        size_t get(const Identifier& propertyName) const;
+        size_t get(const Identifier& propertyName, unsigned& attributes) const;
+        void getEnumerablePropertyNames(ExecState*, PropertyNameArray&, JSObject*);
+
+        bool hasGetterSetterProperties() const { return m_hasGetterSetterProperties; }
+        void setHasGetterSetterProperties(bool hasGetterSetterProperties) { m_hasGetterSetterProperties = hasGetterSetterProperties; }
+
+        bool isEmpty() const { return !m_propertyTable; }
+
+    private:
+        StructureID(JSValue* prototype, const TypeInfo&);
+
+        size_t put(const Identifier& propertyName, unsigned attributes);
+        size_t remove(const Identifier& propertyName);
+        void getEnumerablePropertyNamesInternal(PropertyNameArray&) const;
+
+        void expandPropertyMapHashTable();
+        void rehashPropertyMapHashTable();
+        void rehashPropertyMapHashTable(unsigned newTableSize);
+        void createPropertyMapHashTable();
+        void insertIntoPropertyMapHashTable(const PropertyMapEntry&);
+        void checkConsistency();
+
+        PropertyMapHashTable* copyPropertyTable();
+
+        void clearEnumerationCache();
+
+        static const unsigned emptyEntryIndex = 0;
+    
+        static const size_t s_maxTransitionLength = 64;
+
+        TypeInfo m_typeInfo;
+
+        JSValue* m_prototype;
+        RefPtr<StructureIDChain> m_cachedPrototypeChain;
+
+        RefPtr<StructureID> m_previous;
+        UString::Rep* m_nameInPrevious;
+
+        size_t m_transitionCount;
+        union {
+            StructureID* singleTransition;
+            StructureIDTransitionTable* table;
+        } m_transitions;
+
+        RefPtr<PropertyNameArrayData> m_cachedPropertyNameArrayData;
+
+        PropertyMapHashTable* m_propertyTable;
+        Vector<unsigned> m_deletedOffsets;
+
+        size_t m_propertyStorageCapacity;
+
+        size_t m_cachedTransistionOffset;
+
+        bool m_isDictionary : 1;
+        bool m_hasGetterSetterProperties : 1;
+        bool m_usingSingleTransitionSlot : 1;
+        unsigned m_attributesInPrevious : 5;
+    };
+
+    inline size_t StructureID::get(const Identifier& propertyName) const
+    {
+        ASSERT(!propertyName.isNull());
+
+        if (!m_propertyTable)
+            return WTF::notFound;
+
+        UString::Rep* rep = propertyName._ustring.rep();
+
+        unsigned i = rep->computedHash();
+
+#if DUMP_PROPERTYMAP_STATS
+        ++numProbes;
+#endif
+
+        unsigned entryIndex = m_propertyTable->entryIndices[i & m_propertyTable->sizeMask];
+        if (entryIndex == emptyEntryIndex)
+            return WTF::notFound;
+
+        if (rep == m_propertyTable->entries()[entryIndex - 1].key)
+            return m_propertyTable->entries()[entryIndex - 1].offset;
+
+#if DUMP_PROPERTYMAP_STATS
+        ++numCollisions;
+#endif
+
+        unsigned k = 1 | WTF::doubleHash(rep->computedHash());
+
+        while (1) {
+            i += k;
+
+#if DUMP_PROPERTYMAP_STATS
+            ++numRehashes;
+#endif
+
+            entryIndex = m_propertyTable->entryIndices[i & m_propertyTable->sizeMask];
+            if (entryIndex == emptyEntryIndex)
+                return WTF::notFound;
+
+            if (rep == m_propertyTable->entries()[entryIndex - 1].key)
+                return m_propertyTable->entries()[entryIndex - 1].offset;
+        }
+    }
+
+} // namespace JSC
+
+#endif // StructureID_h