blob: 4608c63adbaccfe2e73ebb127c546854611132a3 [file] [log] [blame]
/*
* Copyright (C) 2014-2017 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 INC. AND ITS CONTRIBUTORS ``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 INC. OR ITS 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.
*/
#pragma once
#include "JSCast.h"
#include "Operations.h"
#include "PropertyNameArray.h"
#include "Structure.h"
namespace JSC {
class JSPropertyNameEnumerator final : public JSCell {
public:
typedef JSCell Base;
static const unsigned StructureFlags = Base::StructureFlags | StructureIsImmortal;
static JSPropertyNameEnumerator* create(VM&);
static JSPropertyNameEnumerator* create(VM&, Structure*, uint32_t, uint32_t, PropertyNameArray&&);
static const bool needsDestruction = true;
static void destroy(JSCell*);
static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype)
{
return Structure::create(vm, globalObject, prototype, TypeInfo(CellType, StructureFlags), info());
}
DECLARE_EXPORT_INFO;
JSString* propertyNameAtIndex(uint32_t index) const
{
if (index >= m_propertyNames.size())
return nullptr;
return m_propertyNames[index].get();
}
StructureChain* cachedPrototypeChain() const { return m_prototypeChain.get(); }
void setCachedPrototypeChain(VM& vm, StructureChain* prototypeChain) { return m_prototypeChain.set(vm, this, prototypeChain); }
Structure* cachedStructure(VM& vm) const
{
if (!m_cachedStructureID)
return nullptr;
return vm.heap.structureIDTable().get(m_cachedStructureID);
}
StructureID cachedStructureID() const { return m_cachedStructureID; }
uint32_t indexedLength() const { return m_indexedLength; }
uint32_t endStructurePropertyIndex() const { return m_endStructurePropertyIndex; }
uint32_t endGenericPropertyIndex() const { return m_endGenericPropertyIndex; }
uint32_t cachedInlineCapacity() const { return m_cachedInlineCapacity; }
static ptrdiff_t cachedStructureIDOffset() { return OBJECT_OFFSETOF(JSPropertyNameEnumerator, m_cachedStructureID); }
static ptrdiff_t indexedLengthOffset() { return OBJECT_OFFSETOF(JSPropertyNameEnumerator, m_indexedLength); }
static ptrdiff_t endStructurePropertyIndexOffset() { return OBJECT_OFFSETOF(JSPropertyNameEnumerator, m_endStructurePropertyIndex); }
static ptrdiff_t endGenericPropertyIndexOffset() { return OBJECT_OFFSETOF(JSPropertyNameEnumerator, m_endGenericPropertyIndex); }
static ptrdiff_t cachedInlineCapacityOffset() { return OBJECT_OFFSETOF(JSPropertyNameEnumerator, m_cachedInlineCapacity); }
static ptrdiff_t cachedPropertyNamesVectorOffset()
{
return OBJECT_OFFSETOF(JSPropertyNameEnumerator, m_propertyNames) + Vector<WriteBarrier<JSString>>::dataMemoryOffset();
}
static void visitChildren(JSCell*, SlotVisitor&);
private:
JSPropertyNameEnumerator(VM&, StructureID, uint32_t);
void finishCreation(VM&, uint32_t, uint32_t, RefPtr<PropertyNameArrayData>&&);
Vector<WriteBarrier<JSString>> m_propertyNames;
StructureID m_cachedStructureID;
WriteBarrier<StructureChain> m_prototypeChain;
uint32_t m_indexedLength;
uint32_t m_endStructurePropertyIndex;
uint32_t m_endGenericPropertyIndex;
uint32_t m_cachedInlineCapacity;
};
inline JSPropertyNameEnumerator* propertyNameEnumerator(ExecState* exec, JSObject* base)
{
VM& vm = exec->vm();
auto scope = DECLARE_THROW_SCOPE(vm);
uint32_t indexedLength = base->methodTable(vm)->getEnumerableLength(exec, base);
JSPropertyNameEnumerator* enumerator = nullptr;
Structure* structure = base->structure(vm);
if (!indexedLength
&& (enumerator = structure->cachedPropertyNameEnumerator())
&& enumerator->cachedPrototypeChain() == structure->prototypeChain(exec, base))
return enumerator;
uint32_t numberStructureProperties = 0;
PropertyNameArray propertyNames(&vm, PropertyNameMode::Strings, PrivateSymbolMode::Exclude);
if (structure->canAccessPropertiesQuicklyForEnumeration() && indexedLength == base->getArrayLength()) {
base->methodTable(vm)->getStructurePropertyNames(base, exec, propertyNames, EnumerationMode());
scope.assertNoException();
numberStructureProperties = propertyNames.size();
base->methodTable(vm)->getGenericPropertyNames(base, exec, propertyNames, EnumerationMode());
} else {
// Generic property names vector contains all indexed property names.
// So disable indexed property enumeration phase by setting |indexedLength| to 0.
indexedLength = 0;
base->methodTable(vm)->getPropertyNames(base, exec, propertyNames, EnumerationMode());
}
RETURN_IF_EXCEPTION(scope, nullptr);
ASSERT(propertyNames.size() < UINT32_MAX);
bool sawPolyProto;
bool successfullyNormalizedChain = normalizePrototypeChain(exec, base, sawPolyProto) != InvalidPrototypeChain;
Structure* structureAfterGettingPropertyNames = base->structure(vm);
enumerator = JSPropertyNameEnumerator::create(vm, structureAfterGettingPropertyNames, indexedLength, numberStructureProperties, WTFMove(propertyNames));
if (!indexedLength && successfullyNormalizedChain && structureAfterGettingPropertyNames == structure) {
enumerator->setCachedPrototypeChain(vm, structure->prototypeChain(exec, base));
if (structure->canCachePropertyNameEnumerator())
structure->setCachedPropertyNameEnumerator(vm, enumerator);
}
return enumerator;
}
} // namespace JSC