--- /dev/null
+/*
+ * 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 Structure_h
+#define Structure_h
+
+#include "Identifier.h"
+#include "JSType.h"
+#include "JSValue.h"
+#include "PropertyMapHashTable.h"
+#include "StructureChain.h"
+#include "StructureTransitionTable.h"
+#include "TypeInfo.h"
+#include "UString.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 Structure : public RefCounted<Structure> {
+ public:
+ friend class JIT;
+ static PassRefPtr<Structure> create(JSValuePtr prototype, const TypeInfo& typeInfo)
+ {
+ return adoptRef(new Structure(prototype, typeInfo));
+ }
+
+ static void startIgnoringLeaks();
+ static void stopIgnoringLeaks();
+
+ static void dumpStatistics();
+
+ static PassRefPtr<Structure> addPropertyTransition(Structure*, const Identifier& propertyName, unsigned attributes, size_t& offset);
+ static PassRefPtr<Structure> addPropertyTransitionToExistingStructure(Structure*, const Identifier& propertyName, unsigned attributes, size_t& offset);
+ static PassRefPtr<Structure> removePropertyTransition(Structure*, const Identifier& propertyName, size_t& offset);
+ static PassRefPtr<Structure> changePrototypeTransition(Structure*, JSValuePtr prototype);
+ static PassRefPtr<Structure> getterSetterTransition(Structure*);
+ static PassRefPtr<Structure> toDictionaryTransition(Structure*);
+ static PassRefPtr<Structure> fromDictionaryTransition(Structure*);
+
+ ~Structure();
+
+ 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(JSValuePtr prototype) { m_prototype = prototype; }
+
+ bool isDictionary() const { return m_isDictionary; }
+
+ const TypeInfo& typeInfo() const { return m_typeInfo; }
+
+ JSValuePtr storedPrototype() const { return m_prototype; }
+ JSValuePtr prototypeForLookup(ExecState*) const;
+ StructureChain* prototypeChain(ExecState*) const;
+
+ Structure* previousID() const { return m_previous.get(); }
+
+ void growPropertyStorageCapacity();
+ size_t propertyStorageCapacity() const { return m_propertyStorageCapacity; }
+ size_t propertyStorageSize() const { return m_propertyTable ? m_propertyTable->keyCount + (m_propertyTable->deletedOffsets ? m_propertyTable->deletedOffsets->size() : 0) : m_offset + 1; }
+
+ size_t get(const Identifier& propertyName);
+ size_t get(const Identifier& propertyName, unsigned& attributes);
+ void getEnumerablePropertyNames(ExecState*, PropertyNameArray&, JSObject*);
+
+ bool hasGetterSetterProperties() const { return m_hasGetterSetterProperties; }
+ void setHasGetterSetterProperties(bool hasGetterSetterProperties) { m_hasGetterSetterProperties = hasGetterSetterProperties; }
+
+ bool isEmpty() const { return m_propertyTable ? !m_propertyTable->keyCount : m_offset == noOffset; }
+
+ private:
+ Structure(JSValuePtr prototype, const TypeInfo&);
+
+ size_t put(const Identifier& propertyName, unsigned attributes);
+ size_t remove(const Identifier& propertyName);
+ void getEnumerableNamesFromPropertyTable(PropertyNameArray&);
+ void getEnumerableNamesFromClassInfoTable(ExecState*, const ClassInfo*, PropertyNameArray&);
+
+ void expandPropertyMapHashTable();
+ void rehashPropertyMapHashTable();
+ void rehashPropertyMapHashTable(unsigned newTableSize);
+ void createPropertyMapHashTable();
+ void createPropertyMapHashTable(unsigned newTableSize);
+ void insertIntoPropertyMapHashTable(const PropertyMapEntry&);
+ void checkConsistency();
+
+ PropertyMapHashTable* copyPropertyTable();
+ void materializePropertyMap();
+ void materializePropertyMapIfNecessary()
+ {
+ if (m_propertyTable || !m_previous)
+ return;
+ materializePropertyMap();
+ }
+
+ void clearEnumerationCache();
+
+ void* addressOfCount()
+ {
+ return &m_refCount;
+ }
+
+ 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 unsigned emptyEntryIndex = 0;
+
+ static const signed char s_maxTransitionLength = 64;
+
+ static const signed char noOffset = -1;
+
+ TypeInfo m_typeInfo;
+
+ JSValuePtr m_prototype;
+ mutable RefPtr<StructureChain> m_cachedPrototypeChain;
+
+ RefPtr<Structure> m_previous;
+ RefPtr<UString::Rep> m_nameInPrevious;
+
+ union {
+ Structure* singleTransition;
+ StructureTransitionTable* table;
+ } m_transitions;
+
+ RefPtr<PropertyNameArrayData> m_cachedPropertyNameArrayData;
+
+ PropertyMapHashTable* m_propertyTable;
+
+ size_t m_propertyStorageCapacity;
+ signed char m_offset;
+
+ bool m_isDictionary : 1;
+ bool m_isPinnedPropertyTable : 1;
+ bool m_hasGetterSetterProperties : 1;
+ bool m_usingSingleTransitionSlot : 1;
+ unsigned m_attributesInPrevious : 5;
+ };
+
+ inline size_t Structure::get(const Identifier& propertyName)
+ {
+ ASSERT(!propertyName.isNull());
+
+ materializePropertyMapIfNecessary();
+ 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 // Structure_h
projects / apple / javascriptcore.git / blobdiff