JSPropertyNameIterator* JSPropertyNameIterator::create(ExecState* exec, JSObject* o)
{
ASSERT(!o->structure()->enumerationCache() ||
o->structure()->enumerationCache()->cachedStructure() != o->structure() ||
o->structure()->enumerationCache()->cachedPrototypeChain() != o->structure()->prototypeChain(exec));
PropertyNameArray propertyNames(exec);
o->methodTable()->getPropertyNames(o, exec, propertyNames, ExcludeDontEnumProperties);
size_t numCacheableSlots = 0;
if (!o->structure()->hasNonEnumerableProperties() && !o->structure()->hasGetterSetterProperties()
&& !o->structure()->isUncacheableDictionary() && !o->structure()->typeInfo().overridesGetPropertyNames())
numCacheableSlots = o->structure()->totalStorageSize();
JSPropertyNameIterator* jsPropertyNameIterator = new (NotNull, allocateCell<JSPropertyNameIterator>(*exec->heap())) JSPropertyNameIterator(exec, propertyNames.data(), numCacheableSlots);
jsPropertyNameIterator->finishCreation(exec, propertyNames.data(), o);
if (o->structure()->isDictionary())
return jsPropertyNameIterator;
if (o->structure()->typeInfo().overridesGetPropertyNames())
return jsPropertyNameIterator;
size_t count = normalizePrototypeChain(exec, o);
StructureChain* structureChain = o->structure()->prototypeChain(exec);
WriteBarrier<Structure>* structure = structureChain->head();
for (size_t i = 0; i < count; ++i) {
if (structure[i]->typeInfo().overridesGetPropertyNames())
return jsPropertyNameIterator;
}
jsPropertyNameIterator->setCachedPrototypeChain(exec->globalData(), structureChain);
jsPropertyNameIterator->setCachedStructure(exec->globalData(), o->structure());
o->structure()->setEnumerationCache(exec->globalData(), jsPropertyNameIterator);
return jsPropertyNameIterator;
}
JSPropertyNameIterator* JSPropertyNameIterator::create(ExecState* exec, JSObject* o)
{
ASSERT(!o->structure()->enumerationCache() ||
o->structure()->enumerationCache()->cachedStructure() != o->structure() ||
o->structure()->enumerationCache()->cachedPrototypeChain() != o->structure()->prototypeChain(exec));
PropertyNameArray propertyNames(exec);
o->getPropertyNames(exec, propertyNames);
size_t numCacheableSlots = 0;
if (!o->structure()->hasNonEnumerableProperties() && !o->structure()->hasAnonymousSlots() &&
!o->structure()->isUncacheableDictionary() && !o->structure()->typeInfo().overridesGetPropertyNames())
numCacheableSlots = o->structure()->propertyStorageSize();
JSPropertyNameIterator* jsPropertyNameIterator = new (exec) JSPropertyNameIterator(exec, propertyNames.data(), numCacheableSlots);
if (o->structure()->isDictionary())
return jsPropertyNameIterator;
if (o->structure()->typeInfo().overridesGetPropertyNames())
return jsPropertyNameIterator;
size_t count = normalizePrototypeChain(exec, o);
StructureChain* structureChain = o->structure()->prototypeChain(exec);
RefPtr<Structure>* structure = structureChain->head();
for (size_t i = 0; i < count; ++i) {
if (structure[i]->typeInfo().overridesGetPropertyNames())
return jsPropertyNameIterator;
}
jsPropertyNameIterator->setCachedPrototypeChain(structureChain);
jsPropertyNameIterator->setCachedStructure(o->structure());
o->structure()->setEnumerationCache(jsPropertyNameIterator);
return jsPropertyNameIterator;
}
void StructureChain::visitChildren(JSCell* cell, SlotVisitor& visitor)
{
StructureChain* thisObject = jsCast<StructureChain*>(cell);
ASSERT_GC_OBJECT_INHERITS(thisObject, info());
ASSERT(thisObject->structure()->typeInfo().overridesVisitChildren());
size_t i = 0;
while (thisObject->m_vector[i])
visitor.append(&thisObject->m_vector[i++]);
}
void Structure::getEnumerablePropertyNames(ExecState* exec, PropertyNameArray& propertyNames, JSObject* baseObject)
{
bool shouldCache = propertyNames.shouldCache() && !(propertyNames.size() || isDictionary());
if (shouldCache && m_cachedPropertyNameArrayData) {
if (m_cachedPropertyNameArrayData->cachedPrototypeChain() == prototypeChain(exec)) {
propertyNames.setData(m_cachedPropertyNameArrayData);
return;
}
clearEnumerationCache();
}
baseObject->getOwnPropertyNames(exec, propertyNames);
if (m_prototype.isObject()) {
propertyNames.setShouldCache(false); // No need for our prototypes to waste memory on caching, since they're not being enumerated directly.
JSObject* prototype = asObject(m_prototype);
while(1) {
if (!prototype->structure()->typeInfo().hasDefaultGetPropertyNames()) {
prototype->getPropertyNames(exec, propertyNames);
break;
}
prototype->getOwnPropertyNames(exec, propertyNames);
JSValue nextProto = prototype->prototype();
if (!nextProto.isObject())
break;
prototype = asObject(nextProto);
}
}
if (shouldCache) {
StructureChain* protoChain = prototypeChain(exec);
m_cachedPropertyNameArrayData = propertyNames.data();
if (!protoChain->isCacheable())
return;
m_cachedPropertyNameArrayData->setCachedPrototypeChain(protoChain);
m_cachedPropertyNameArrayData->setCachedStructure(this);
}
}
