runtime/StructureInlines.h

   1 /*
   2  * Copyright (C) 2013 Apple Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #ifndef StructureInlines_h
  27 #define StructureInlines_h
  28
  29 #include "PropertyMapHashTable.h"
  30 #include "Structure.h"
  31
  32 namespace JSC {
  33
  34 inline Structure* Structure::create(VM& vm, JSGlobalObject* globalObject, JSValue prototype, const TypeInfo& typeInfo, const ClassInfo* classInfo, IndexingType indexingType, unsigned inlineCapacity)
  35 {
  36     ASSERT(vm.structureStructure);
  37     ASSERT(classInfo);
  38     Structure* structure = new (NotNull, allocateCell<Structure>(vm.heap)) Structure(vm, globalObject, prototype, typeInfo, classInfo, indexingType, inlineCapacity);
  39     structure->finishCreation(vm);
  40     return structure;
  41 }
  42
  43 inline Structure* Structure::createStructure(VM& vm)
  44 {
  45     ASSERT(!vm.structureStructure);
  46     Structure* structure = new (NotNull, allocateCell<Structure>(vm.heap)) Structure(vm);
  47     structure->finishCreation(vm, CreatingEarlyCell);
  48     return structure;
  49 }
  50
  51 inline Structure* Structure::create(VM& vm, const Structure* structure)
  52 {
  53     ASSERT(vm.structureStructure);
  54     Structure* newStructure = new (NotNull, allocateCell<Structure>(vm.heap)) Structure(vm, structure);
  55     newStructure->finishCreation(vm);
  56     return newStructure;
  57 }
  58
  59 inline PropertyOffset Structure::get(VM& vm, PropertyName propertyName)
  60 {
  61     ASSERT(structure()->classInfo() == &s_info);
  62     materializePropertyMapIfNecessary(vm);
  63     if (!propertyTable())
  64         return invalidOffset;
  65
  66     PropertyMapEntry* entry = propertyTable()->find(propertyName.uid()).first;
  67     return entry ? entry->offset : invalidOffset;
  68 }
  69
  70 inline PropertyOffset Structure::get(VM& vm, const WTF::String& name)
  71 {
  72     ASSERT(structure()->classInfo() == &s_info);
  73     materializePropertyMapIfNecessary(vm);
  74     if (!propertyTable())
  75         return invalidOffset;
  76
  77     PropertyMapEntry* entry = propertyTable()->findWithString(name.impl()).first;
  78     return entry ? entry->offset : invalidOffset;
  79 }
  80
  81 inline bool Structure::masqueradesAsUndefined(JSGlobalObject* lexicalGlobalObject)
  82 {
  83     return typeInfo().masqueradesAsUndefined() && globalObject() == lexicalGlobalObject;
  84 }
  85
  86 ALWAYS_INLINE void SlotVisitor::internalAppend(JSCell* cell)
  87 {
  88     ASSERT(!m_isCheckingForDefaultMarkViolation);
  89     if (!cell)
  90         return;
  91 #if ENABLE(GC_VALIDATION)
  92     validate(cell);
  93 #endif
  94     if (Heap::testAndSetMarked(cell) || !cell->structure())
  95         return;
  96
  97     m_visitCount++;
  98
  99     MARK_LOG_CHILD(*this, cell);
 100
 101     // Should never attempt to mark something that is zapped.
 102     ASSERT(!cell->isZapped());
 103
 104     m_stack.append(cell);
 105 }
 106
 107 inline bool Structure::transitivelyTransitionedFrom(Structure* structureToFind)
 108 {
 109     for (Structure* current = this; current; current = current->previousID()) {
 110         if (current == structureToFind)
 111             return true;
 112     }
 113     return false;
 114 }
 115
 116 inline void Structure::setEnumerationCache(VM& vm, JSPropertyNameIterator* enumerationCache)
 117 {
 118     ASSERT(!isDictionary());
 119     if (!typeInfo().structureHasRareData())
 120         allocateRareData(vm);
 121     rareData()->setEnumerationCache(vm, this, enumerationCache);
 122 }
 123
 124 inline JSPropertyNameIterator* Structure::enumerationCache()
 125 {
 126     if (!typeInfo().structureHasRareData())
 127         return 0;
 128     return rareData()->enumerationCache();
 129 }
 130
 131 inline JSValue Structure::prototypeForLookup(JSGlobalObject* globalObject) const
 132 {
 133     if (isObject())
 134         return m_prototype.get();
 135
 136     ASSERT(typeInfo().type() == StringType);
 137     return globalObject->stringPrototype();
 138 }
 139
 140 inline JSValue Structure::prototypeForLookup(ExecState* exec) const
 141 {
 142     return prototypeForLookup(exec->lexicalGlobalObject());
 143 }
 144
 145 inline StructureChain* Structure::prototypeChain(VM& vm, JSGlobalObject* globalObject) const
 146 {
 147     // We cache our prototype chain so our clients can share it.
 148     if (!isValid(globalObject, m_cachedPrototypeChain.get())) {
 149         JSValue prototype = prototypeForLookup(globalObject);
 150         m_cachedPrototypeChain.set(vm, this, StructureChain::create(vm, prototype.isNull() ? 0 : asObject(prototype)->structure()));
 151     }
 152     return m_cachedPrototypeChain.get();
 153 }
 154
 155 inline StructureChain* Structure::prototypeChain(ExecState* exec) const
 156 {
 157     return prototypeChain(exec->vm(), exec->lexicalGlobalObject());
 158 }
 159
 160 inline bool Structure::isValid(JSGlobalObject* globalObject, StructureChain* cachedPrototypeChain) const
 161 {
 162     if (!cachedPrototypeChain)
 163         return false;
 164
 165     JSValue prototype = prototypeForLookup(globalObject);
 166     WriteBarrier<Structure>* cachedStructure = cachedPrototypeChain->head();
 167     while (*cachedStructure && !prototype.isNull()) {
 168         if (asObject(prototype)->structure() != cachedStructure->get())
 169             return false;
 170         ++cachedStructure;
 171         prototype = asObject(prototype)->prototype();
 172     }
 173     return prototype.isNull() && !*cachedStructure;
 174 }
 175
 176 inline bool Structure::isValid(ExecState* exec, StructureChain* cachedPrototypeChain) const
 177 {
 178     return isValid(exec->lexicalGlobalObject(), cachedPrototypeChain);
 179 }
 180
 181 inline bool Structure::putWillGrowOutOfLineStorage()
 182 {
 183     checkOffsetConsistency();
 184
 185     ASSERT(outOfLineCapacity() >= outOfLineSize());
 186
 187     if (!propertyTable()) {
 188         unsigned currentSize = numberOfOutOfLineSlotsForLastOffset(m_offset);
 189         ASSERT(outOfLineCapacity() >= currentSize);
 190         return currentSize == outOfLineCapacity();
 191     }
 192
 193     ASSERT(totalStorageCapacity() >= propertyTable()->propertyStorageSize());
 194     if (propertyTable()->hasDeletedOffset())
 195         return false;
 196
 197     ASSERT(totalStorageCapacity() >= propertyTable()->size());
 198     return propertyTable()->size() == totalStorageCapacity();
 199 }
 200
 201 ALWAYS_INLINE WriteBarrier<PropertyTable>& Structure::propertyTable()
 202 {
 203     ASSERT(!globalObject() || !globalObject()->vm().heap.isBusy());
 204     return m_propertyTableUnsafe;
 205 }
 206
 207 ALWAYS_INLINE bool Structure::checkOffsetConsistency() const
 208 {
 209     PropertyTable* propertyTable = m_propertyTableUnsafe.get();
 210
 211     if (!propertyTable) {
 212         ASSERT(!m_isPinnedPropertyTable);
 213         return true;
 214     }
 215
 216     RELEASE_ASSERT(numberOfSlotsForLastOffset(m_offset, m_inlineCapacity) == propertyTable->propertyStorageSize());
 217     unsigned totalSize = propertyTable->propertyStorageSize();
 218     RELEASE_ASSERT((totalSize < inlineCapacity() ? 0 : totalSize - inlineCapacity()) == numberOfOutOfLineSlotsForLastOffset(m_offset));
 219
 220     return true;
 221 }
 222
 223 } // namespace JSC
 224
 225 #endif // StructureInlines_h
 226