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/*
* Copyright (C) 1999-2001 Harri Porten (porten@kde.org)
* Copyright (C) 2001 Peter Kelly (pmk@post.com)
* Copyright (C) 2003-2019 Apple Inc. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
#pragma once
#include "ArrayConventions.h"
#include "ArrayStorage.h"
#include "Butterfly.h"
#include "CPU.h"
#include "CagedBarrierPtr.h"
#include "CallFrame.h"
#include "ClassInfo.h"
#include "CustomGetterSetter.h"
#include "DOMAttributeGetterSetter.h"
#include "Heap.h"
#include "IndexingHeaderInlines.h"
#include "JSCast.h"
#include "ObjectInitializationScope.h"
#include "PropertySlot.h"
#include "PropertyStorage.h"
#include "PutDirectIndexMode.h"
#include "PutPropertySlot.h"
#include "Structure.h"
#include "StructureTransitionTable.h"
#include "VM.h"
#include "JSString.h"
#include "SparseArrayValueMap.h"
#include <wtf/StdLibExtras.h>
namespace JSC {
namespace DOMJIT {
class Signature;
}
inline JSCell* getJSFunction(JSValue value)
{
if (value.isCell() && (value.asCell()->type() == JSFunctionType))
return value.asCell();
return 0;
}
class Exception;
class GetterSetter;
class InternalFunction;
class JSFunction;
class LLIntOffsetsExtractor;
class MarkedBlock;
class PropertyDescriptor;
class PropertyNameArray;
class Structure;
class ThrowScope;
struct HashTable;
struct HashTableValue;
JS_EXPORT_PRIVATE Exception* throwTypeError(ExecState*, ThrowScope&, const String&);
extern JS_EXPORT_PRIVATE const ASCIILiteral NonExtensibleObjectPropertyDefineError;
extern JS_EXPORT_PRIVATE const ASCIILiteral ReadonlyPropertyWriteError;
extern JS_EXPORT_PRIVATE const ASCIILiteral ReadonlyPropertyChangeError;
extern JS_EXPORT_PRIVATE const ASCIILiteral UnableToDeletePropertyError;
extern JS_EXPORT_PRIVATE const ASCIILiteral UnconfigurablePropertyChangeAccessMechanismError;
extern JS_EXPORT_PRIVATE const ASCIILiteral UnconfigurablePropertyChangeConfigurabilityError;
extern JS_EXPORT_PRIVATE const ASCIILiteral UnconfigurablePropertyChangeEnumerabilityError;
extern JS_EXPORT_PRIVATE const ASCIILiteral UnconfigurablePropertyChangeWritabilityError;
COMPILE_ASSERT(PropertyAttribute::None < FirstInternalAttribute, None_is_below_FirstInternalAttribute);
COMPILE_ASSERT(PropertyAttribute::ReadOnly < FirstInternalAttribute, ReadOnly_is_below_FirstInternalAttribute);
COMPILE_ASSERT(PropertyAttribute::DontEnum < FirstInternalAttribute, DontEnum_is_below_FirstInternalAttribute);
COMPILE_ASSERT(PropertyAttribute::DontDelete < FirstInternalAttribute, DontDelete_is_below_FirstInternalAttribute);
COMPILE_ASSERT(PropertyAttribute::Accessor < FirstInternalAttribute, Accessor_is_below_FirstInternalAttribute);
class JSFinalObject;
class JSObject : public JSCell {
friend class BatchedTransitionOptimizer;
friend class JIT;
friend class JSCell;
friend class JSFinalObject;
friend class MarkedBlock;
JS_EXPORT_PRIVATE friend bool setUpStaticFunctionSlot(VM&, const HashTableValue*, JSObject*, PropertyName, PropertySlot&);
enum PutMode {
PutModePut,
PutModeDefineOwnProperty,
};
public:
typedef JSCell Base;
// This is a super dangerous method for JITs. Sometimes the JITs will want to create either a
// JSFinalObject or a JSArray. This is the method that will do that.
static JSObject* createRawObject(ExecState* exec, Structure* structure, Butterfly* = nullptr);
JS_EXPORT_PRIVATE static size_t estimatedSize(JSCell*, VM&);
JS_EXPORT_PRIVATE static void visitChildren(JSCell*, SlotVisitor&);
JS_EXPORT_PRIVATE static void analyzeHeap(JSCell*, HeapAnalyzer&);
JS_EXPORT_PRIVATE static String className(const JSObject*, VM&);
JS_EXPORT_PRIVATE static String calculatedClassName(JSObject*);
// This function is what Object.prototype.toString() will use to get the name of
// an object when using Symbol.toStringTag fails. For the most part there is no
// difference between this and className(). The main use case is for new JS language
// objects to set the default tag to "Object".
JS_EXPORT_PRIVATE static String toStringName(const JSObject*, ExecState*);
// This is the fully virtual [[GetPrototypeOf]] internal function defined
// in the ECMAScript 6 specification. Use this when doing a [[GetPrototypeOf]]
// operation as dictated in the specification.
JSValue getPrototype(VM&, ExecState*);
JS_EXPORT_PRIVATE static JSValue getPrototype(JSObject*, ExecState*);
// This gets the prototype directly off of the structure. This does not do
// dynamic dispatch on the getPrototype method table method. It is not valid
// to use this when performing a [[GetPrototypeOf]] operation in the specification.
// It is valid to use though when you know that you want to directly get it
// without consulting the method table. This is akin to getting the [[Prototype]]
// internal field directly as described in the specification.
JSValue getPrototypeDirect(VM&) const;
// This sets the prototype without checking for cycles and without
// doing dynamic dispatch on [[SetPrototypeOf]] operation in the specification.
// It is not valid to use this when performing a [[SetPrototypeOf]] operation in
// the specification. It is valid to use though when you know that you want to directly
// set it without consulting the method table and when you definitely won't
// introduce a cycle in the prototype chain. This is akin to setting the
// [[Prototype]] internal field directly as described in the specification.
JS_EXPORT_PRIVATE void setPrototypeDirect(VM&, JSValue prototype);
private:
// This is OrdinarySetPrototypeOf in the specification. Section 9.1.2.1
// https://tc39.github.io/ecma262/#sec-ordinarysetprototypeof
JS_EXPORT_PRIVATE bool setPrototypeWithCycleCheck(VM&, ExecState*, JSValue prototype, bool shouldThrowIfCantSet);
public:
// This is the fully virtual [[SetPrototypeOf]] internal function defined
// in the ECMAScript 6 specification. Use this when doing a [[SetPrototypeOf]]
// operation as dictated in the specification.
bool setPrototype(VM&, ExecState*, JSValue prototype, bool shouldThrowIfCantSet = false);
JS_EXPORT_PRIVATE static bool setPrototype(JSObject*, ExecState*, JSValue prototype, bool shouldThrowIfCantSet);
inline bool mayInterceptIndexedAccesses(VM&);
JSValue get(ExecState*, PropertyName) const;
JSValue get(ExecState*, unsigned propertyName) const;
template<bool checkNullStructure = false>
bool getPropertySlot(ExecState*, PropertyName, PropertySlot&);
bool getPropertySlot(ExecState*, unsigned propertyName, PropertySlot&);
template<typename CallbackWhenNoException> typename std::result_of<CallbackWhenNoException(bool, PropertySlot&)>::type getPropertySlot(ExecState*, PropertyName, CallbackWhenNoException) const;
template<typename CallbackWhenNoException> typename std::result_of<CallbackWhenNoException(bool, PropertySlot&)>::type getPropertySlot(ExecState*, PropertyName, PropertySlot&, CallbackWhenNoException) const;
static bool getOwnPropertySlot(JSObject*, ExecState*, PropertyName, PropertySlot&);
JS_EXPORT_PRIVATE static bool getOwnPropertySlotByIndex(JSObject*, ExecState*, unsigned propertyName, PropertySlot&);
bool getOwnPropertySlotInline(ExecState*, PropertyName, PropertySlot&);
static void doPutPropertySecurityCheck(JSObject*, ExecState*, PropertyName, PutPropertySlot&);
// The key difference between this and getOwnPropertySlot is that getOwnPropertySlot
// currently returns incorrect results for the DOM window (with non-own properties)
// being returned. Once this is fixed we should migrate code & remove this method.
JS_EXPORT_PRIVATE bool getOwnPropertyDescriptor(ExecState*, PropertyName, PropertyDescriptor&);
unsigned getArrayLength() const
{
if (!hasIndexedProperties(indexingType()))
return 0;
return m_butterfly->publicLength();
}
unsigned getVectorLength()
{
if (!hasIndexedProperties(indexingType()))
return 0;
return m_butterfly->vectorLength();
}
static bool putInlineForJSObject(JSCell*, ExecState*, PropertyName, JSValue, PutPropertySlot&);
JS_EXPORT_PRIVATE static bool put(JSCell*, ExecState*, PropertyName, JSValue, PutPropertySlot&);
// putByIndex assumes that the receiver is this JSCell object.
JS_EXPORT_PRIVATE static bool putByIndex(JSCell*, ExecState*, unsigned propertyName, JSValue, bool shouldThrow);
// This performs the ECMAScript Set() operation.
ALWAYS_INLINE bool putByIndexInline(ExecState* exec, unsigned propertyName, JSValue value, bool shouldThrow)
{
VM& vm = exec->vm();
if (canSetIndexQuickly(propertyName, value)) {
setIndexQuickly(vm, propertyName, value);
return true;
}
return methodTable(vm)->putByIndex(this, exec, propertyName, value, shouldThrow);
}
// This is similar to the putDirect* methods:
// - the prototype chain is not consulted
// - accessors are not called.
// - it will ignore extensibility and read-only properties if PutDirectIndexLikePutDirect is passed as the mode (the default).
// This method creates a property with attributes writable, enumerable and configurable all set to true if attributes is zero,
// otherwise, it creates a property with the provided attributes. Semantically, this is performing defineOwnProperty.
bool putDirectIndex(ExecState* exec, unsigned propertyName, JSValue value, unsigned attributes, PutDirectIndexMode mode)
{
ASSERT(!value.isCustomGetterSetter());
auto canSetIndexQuicklyForPutDirect = [&] () -> bool {
switch (indexingMode()) {
case ALL_BLANK_INDEXING_TYPES:
case ALL_UNDECIDED_INDEXING_TYPES:
return false;
case ALL_WRITABLE_INT32_INDEXING_TYPES:
case ALL_WRITABLE_DOUBLE_INDEXING_TYPES:
case ALL_WRITABLE_CONTIGUOUS_INDEXING_TYPES:
case ALL_ARRAY_STORAGE_INDEXING_TYPES:
return propertyName < m_butterfly->vectorLength();
default:
if (isCopyOnWrite(indexingMode()))
return false;
RELEASE_ASSERT_NOT_REACHED();
return false;
}
};
if (!attributes && canSetIndexQuicklyForPutDirect()) {
setIndexQuickly(exec->vm(), propertyName, value);
return true;
}
return putDirectIndexSlowOrBeyondVectorLength(exec, propertyName, value, attributes, mode);
}
// This is semantically equivalent to performing defineOwnProperty(propertyName, {configurable:true, writable:true, enumerable:true, value:value}).
bool putDirectIndex(ExecState* exec, unsigned propertyName, JSValue value)
{
return putDirectIndex(exec, propertyName, value, 0, PutDirectIndexLikePutDirect);
}
// A generally non-throwing version of putDirect and putDirectIndex.
// However, it's only guaranteed to not throw based on what the receiver is.
// For example, if the receiver is a ProxyObject, this is not guaranteed, since
// it may call into arbitrary JS code. It's the responsibility of the user of
// this API to ensure that the receiver object is a well known type if they
// want to ensure that this won't throw an exception.
JS_EXPORT_PRIVATE bool putDirectMayBeIndex(ExecState*, PropertyName, JSValue);
bool hasIndexingHeader(VM& vm) const
{
return structure(vm)->hasIndexingHeader(this);
}
bool canGetIndexQuicklyForTypedArray(unsigned) const;
JSValue getIndexQuicklyForTypedArray(unsigned) const;
bool canGetIndexQuickly(unsigned i) const
{
const Butterfly* butterfly = this->butterfly();
switch (indexingType()) {
case ALL_BLANK_INDEXING_TYPES:
return canGetIndexQuicklyForTypedArray(i);
case ALL_UNDECIDED_INDEXING_TYPES:
return false;
case ALL_INT32_INDEXING_TYPES:
case ALL_CONTIGUOUS_INDEXING_TYPES:
return i < butterfly->vectorLength() && butterfly->contiguous().at(this, i);
case ALL_DOUBLE_INDEXING_TYPES: {
if (i >= butterfly->vectorLength())
return false;
double value = butterfly->contiguousDouble().at(this, i);
if (value != value)
return false;
return true;
}
case ALL_ARRAY_STORAGE_INDEXING_TYPES:
return i < butterfly->arrayStorage()->vectorLength() && butterfly->arrayStorage()->m_vector[i];
default:
RELEASE_ASSERT_NOT_REACHED();
return false;
}
}
JSValue getIndexQuickly(unsigned i) const
{
const Butterfly* butterfly = this->butterfly();
switch (indexingType()) {
case ALL_INT32_INDEXING_TYPES:
return jsNumber(butterfly->contiguous().at(this, i).get().asInt32());
case ALL_CONTIGUOUS_INDEXING_TYPES:
return butterfly->contiguous().at(this, i).get();
case ALL_DOUBLE_INDEXING_TYPES:
return JSValue(JSValue::EncodeAsDouble, butterfly->contiguousDouble().at(this, i));
case ALL_ARRAY_STORAGE_INDEXING_TYPES:
return butterfly->arrayStorage()->m_vector[i].get();
case ALL_BLANK_INDEXING_TYPES:
return getIndexQuicklyForTypedArray(i);
default:
RELEASE_ASSERT_NOT_REACHED();
return JSValue();
}
}
JSValue tryGetIndexQuickly(unsigned i) const
{
const Butterfly* butterfly = this->butterfly();
switch (indexingType()) {
case ALL_BLANK_INDEXING_TYPES:
if (canGetIndexQuicklyForTypedArray(i))
return getIndexQuicklyForTypedArray(i);
break;
case ALL_UNDECIDED_INDEXING_TYPES:
break;
case ALL_INT32_INDEXING_TYPES:
if (i < butterfly->publicLength()) {
JSValue result = butterfly->contiguous().at(this, i).get();
ASSERT(result.isInt32() || !result);
return result;
}
break;
case ALL_CONTIGUOUS_INDEXING_TYPES:
if (i < butterfly->publicLength())
return butterfly->contiguous().at(this, i).get();
break;
case ALL_DOUBLE_INDEXING_TYPES: {
if (i >= butterfly->publicLength())
break;
double result = butterfly->contiguousDouble().at(this, i);
if (result != result)
break;
return JSValue(JSValue::EncodeAsDouble, result);
}
case ALL_ARRAY_STORAGE_INDEXING_TYPES:
if (i < butterfly->arrayStorage()->vectorLength())
return butterfly->arrayStorage()->m_vector[i].get();
break;
default:
RELEASE_ASSERT_NOT_REACHED();
break;
}
return JSValue();
}
JSValue getDirectIndex(ExecState* exec, unsigned i)
{
if (JSValue result = tryGetIndexQuickly(i))
return result;
PropertySlot slot(this, PropertySlot::InternalMethodType::Get);
if (methodTable(exec->vm())->getOwnPropertySlotByIndex(this, exec, i, slot))
return slot.getValue(exec, i);
return JSValue();
}
JSValue getIndex(ExecState* exec, unsigned i) const
{
if (JSValue result = tryGetIndexQuickly(i))
return result;
return get(exec, i);
}
bool canSetIndexQuicklyForTypedArray(unsigned, JSValue) const;
void setIndexQuicklyForTypedArray(unsigned, JSValue);
bool canSetIndexQuickly(unsigned i, JSValue value)
{
Butterfly* butterfly = this->butterfly();
switch (indexingMode()) {
case ALL_BLANK_INDEXING_TYPES:
return canSetIndexQuicklyForTypedArray(i, value);
case ALL_UNDECIDED_INDEXING_TYPES:
return false;
case ALL_WRITABLE_INT32_INDEXING_TYPES:
case ALL_WRITABLE_DOUBLE_INDEXING_TYPES:
case ALL_WRITABLE_CONTIGUOUS_INDEXING_TYPES:
case NonArrayWithArrayStorage:
case ArrayWithArrayStorage:
return i < butterfly->vectorLength();
case NonArrayWithSlowPutArrayStorage:
case ArrayWithSlowPutArrayStorage:
return i < butterfly->arrayStorage()->vectorLength()
&& !!butterfly->arrayStorage()->m_vector[i];
default:
if (isCopyOnWrite(indexingMode()))
return false;
RELEASE_ASSERT_NOT_REACHED();
return false;
}
}
void setIndexQuickly(VM& vm, unsigned i, JSValue v)
{
Butterfly* butterfly = m_butterfly.get();
ASSERT(!isCopyOnWrite(indexingMode()));
switch (indexingType()) {
case ALL_INT32_INDEXING_TYPES: {
ASSERT(i < butterfly->vectorLength());
if (!v.isInt32()) {
convertInt32ToDoubleOrContiguousWhilePerformingSetIndex(vm, i, v);
return;
}
FALLTHROUGH;
}
case ALL_CONTIGUOUS_INDEXING_TYPES: {
ASSERT(i < butterfly->vectorLength());
butterfly->contiguous().at(this, i).set(vm, this, v);
if (i >= butterfly->publicLength())
butterfly->setPublicLength(i + 1);
break;
}
case ALL_DOUBLE_INDEXING_TYPES: {
ASSERT(i < butterfly->vectorLength());
if (!v.isNumber()) {
convertDoubleToContiguousWhilePerformingSetIndex(vm, i, v);
return;
}
double value = v.asNumber();
if (value != value) {
convertDoubleToContiguousWhilePerformingSetIndex(vm, i, v);
return;
}
butterfly->contiguousDouble().at(this, i) = value;
if (i >= butterfly->publicLength())
butterfly->setPublicLength(i + 1);
break;
}
case ALL_ARRAY_STORAGE_INDEXING_TYPES: {
ArrayStorage* storage = butterfly->arrayStorage();
WriteBarrier<Unknown>& x = storage->m_vector[i];
JSValue old = x.get();
x.set(vm, this, v);
if (!old) {
++storage->m_numValuesInVector;
if (i >= storage->length())
storage->setLength(i + 1);
}
break;
}
case ALL_BLANK_INDEXING_TYPES:
setIndexQuicklyForTypedArray(i, v);
break;
default:
RELEASE_ASSERT_NOT_REACHED();
}
}
void initializeIndex(ObjectInitializationScope& scope, unsigned i, JSValue v)
{
initializeIndex(scope, i, v, indexingType());
}
// NOTE: Clients of this method may call it more than once for any index, and this is supposed
// to work.
ALWAYS_INLINE void initializeIndex(ObjectInitializationScope& scope, unsigned i, JSValue v, IndexingType indexingType)
{
VM& vm = scope.vm();
Butterfly* butterfly = m_butterfly.get();
switch (indexingType) {
case ALL_UNDECIDED_INDEXING_TYPES: {
setIndexQuicklyToUndecided(vm, i, v);
break;
}
case ALL_INT32_INDEXING_TYPES: {
ASSERT(i < butterfly->publicLength());
ASSERT(i < butterfly->vectorLength());
if (!v.isInt32()) {
convertInt32ToDoubleOrContiguousWhilePerformingSetIndex(vm, i, v);
break;
}
FALLTHROUGH;
}
case ALL_CONTIGUOUS_INDEXING_TYPES: {
ASSERT(i < butterfly->publicLength());
ASSERT(i < butterfly->vectorLength());
butterfly->contiguous().at(this, i).set(vm, this, v);
break;
}
case ALL_DOUBLE_INDEXING_TYPES: {
ASSERT(i < butterfly->publicLength());
ASSERT(i < butterfly->vectorLength());
if (!v.isNumber()) {
convertDoubleToContiguousWhilePerformingSetIndex(vm, i, v);
return;
}
double value = v.asNumber();
if (value != value) {
convertDoubleToContiguousWhilePerformingSetIndex(vm, i, v);
return;
}
butterfly->contiguousDouble().at(this, i) = value;
break;
}
case ALL_ARRAY_STORAGE_INDEXING_TYPES: {
ArrayStorage* storage = butterfly->arrayStorage();
ASSERT(i < storage->length());
ASSERT(i < storage->m_numValuesInVector);
storage->m_vector[i].set(vm, this, v);
break;
}
default:
RELEASE_ASSERT_NOT_REACHED();
}
}
void initializeIndexWithoutBarrier(ObjectInitializationScope& scope, unsigned i, JSValue v)
{
initializeIndexWithoutBarrier(scope, i, v, indexingType());
}
// This version of initializeIndex is for cases where you know that you will not need any
// barriers. This implies not having any data format conversions.
ALWAYS_INLINE void initializeIndexWithoutBarrier(ObjectInitializationScope&, unsigned i, JSValue v, IndexingType indexingType)
{
Butterfly* butterfly = m_butterfly.get();
switch (indexingType) {
case ALL_UNDECIDED_INDEXING_TYPES: {
RELEASE_ASSERT_NOT_REACHED();
break;
}
case ALL_INT32_INDEXING_TYPES: {
ASSERT(i < butterfly->publicLength());
ASSERT(i < butterfly->vectorLength());
RELEASE_ASSERT(v.isInt32());
FALLTHROUGH;
}
case ALL_CONTIGUOUS_INDEXING_TYPES: {
ASSERT(i < butterfly->publicLength());
ASSERT(i < butterfly->vectorLength());
butterfly->contiguous().at(this, i).setWithoutWriteBarrier(v);
break;
}
case ALL_DOUBLE_INDEXING_TYPES: {
ASSERT(i < butterfly->publicLength());
ASSERT(i < butterfly->vectorLength());
RELEASE_ASSERT(v.isNumber());
double value = v.asNumber();
RELEASE_ASSERT(value == value);
butterfly->contiguousDouble().at(this, i) = value;
break;
}
case ALL_ARRAY_STORAGE_INDEXING_TYPES: {
ArrayStorage* storage = butterfly->arrayStorage();
ASSERT(i < storage->length());
ASSERT(i < storage->m_numValuesInVector);
storage->m_vector[i].setWithoutWriteBarrier(v);
break;
}
default:
RELEASE_ASSERT_NOT_REACHED();
}
}
bool hasSparseMap()
{
switch (indexingType()) {
case ALL_BLANK_INDEXING_TYPES:
case ALL_UNDECIDED_INDEXING_TYPES:
case ALL_INT32_INDEXING_TYPES:
case ALL_DOUBLE_INDEXING_TYPES:
case ALL_CONTIGUOUS_INDEXING_TYPES:
return false;
case ALL_ARRAY_STORAGE_INDEXING_TYPES:
return !!m_butterfly->arrayStorage()->m_sparseMap;
default:
RELEASE_ASSERT_NOT_REACHED();
return false;
}
}
bool inSparseIndexingMode()
{
switch (indexingType()) {
case ALL_BLANK_INDEXING_TYPES:
case ALL_UNDECIDED_INDEXING_TYPES:
case ALL_INT32_INDEXING_TYPES:
case ALL_DOUBLE_INDEXING_TYPES:
case ALL_CONTIGUOUS_INDEXING_TYPES:
return false;
case ALL_ARRAY_STORAGE_INDEXING_TYPES:
return m_butterfly->arrayStorage()->inSparseMode();
default:
RELEASE_ASSERT_NOT_REACHED();
return false;
}
}
void enterDictionaryIndexingMode(VM&);
// putDirect is effectively an unchecked vesion of 'defineOwnProperty':
// - the prototype chain is not consulted
// - accessors are not called.
// - attributes will be respected (after the call the property will exist with the given attributes)
// - the property name is assumed to not be an index.
bool putDirect(VM&, PropertyName, JSValue, unsigned attributes = 0);
bool putDirect(VM&, PropertyName, JSValue, PutPropertySlot&);
void putDirectWithoutTransition(VM&, PropertyName, JSValue, unsigned attributes = 0);
bool putDirectNonIndexAccessor(VM&, PropertyName, GetterSetter*, unsigned attributes);
void putDirectNonIndexAccessorWithoutTransition(VM&, PropertyName, GetterSetter*, unsigned attributes);
bool putDirectAccessor(ExecState*, PropertyName, GetterSetter*, unsigned attributes);
JS_EXPORT_PRIVATE bool putDirectCustomAccessor(VM&, PropertyName, JSValue, unsigned attributes);
bool putGetter(ExecState*, PropertyName, JSValue, unsigned attributes);
bool putSetter(ExecState*, PropertyName, JSValue, unsigned attributes);
JS_EXPORT_PRIVATE bool hasProperty(ExecState*, PropertyName) const;
JS_EXPORT_PRIVATE bool hasProperty(ExecState*, unsigned propertyName) const;
bool hasPropertyGeneric(ExecState*, PropertyName, PropertySlot::InternalMethodType) const;
bool hasPropertyGeneric(ExecState*, unsigned propertyName, PropertySlot::InternalMethodType) const;
bool hasOwnProperty(ExecState*, PropertyName, PropertySlot&) const;
bool hasOwnProperty(ExecState*, PropertyName) const;
bool hasOwnProperty(ExecState*, unsigned) const;
JS_EXPORT_PRIVATE static bool deleteProperty(JSCell*, ExecState*, PropertyName);
JS_EXPORT_PRIVATE static bool deletePropertyByIndex(JSCell*, ExecState*, unsigned propertyName);
JS_EXPORT_PRIVATE static JSValue defaultValue(const JSObject*, ExecState*, PreferredPrimitiveType);
JSValue ordinaryToPrimitive(ExecState*, PreferredPrimitiveType) const;
JS_EXPORT_PRIVATE bool hasInstance(ExecState*, JSValue value, JSValue hasInstanceValue);
JS_EXPORT_PRIVATE bool hasInstance(ExecState*, JSValue);
static bool defaultHasInstance(ExecState*, JSValue, JSValue prototypeProperty);
JS_EXPORT_PRIVATE static void getOwnPropertyNames(JSObject*, ExecState*, PropertyNameArray&, EnumerationMode);
JS_EXPORT_PRIVATE static void getOwnNonIndexPropertyNames(JSObject*, ExecState*, PropertyNameArray&, EnumerationMode);
JS_EXPORT_PRIVATE static void getPropertyNames(JSObject*, ExecState*, PropertyNameArray&, EnumerationMode);
JS_EXPORT_PRIVATE static uint32_t getEnumerableLength(ExecState*, JSObject*);
JS_EXPORT_PRIVATE static void getStructurePropertyNames(JSObject*, ExecState*, PropertyNameArray&, EnumerationMode);
JS_EXPORT_PRIVATE static void getGenericPropertyNames(JSObject*, ExecState*, PropertyNameArray&, EnumerationMode);
JS_EXPORT_PRIVATE JSValue toPrimitive(ExecState*, PreferredPrimitiveType = NoPreference) const;
bool getPrimitiveNumber(ExecState*, double& number, JSValue&) const;
JS_EXPORT_PRIVATE double toNumber(ExecState*) const;
JS_EXPORT_PRIVATE JSString* toString(ExecState*) const;
JS_EXPORT_PRIVATE static JSValue toThis(JSCell*, ExecState*, ECMAMode);
// This get function only looks at the property map.
JSValue getDirect(VM& vm, PropertyName propertyName) const
{
Structure* structure = this->structure(vm);
PropertyOffset offset = structure->get(vm, propertyName);
checkOffset(offset, structure->inlineCapacity());
return offset != invalidOffset ? getDirect(offset) : JSValue();
}
JSValue getDirect(VM& vm, PropertyName propertyName, unsigned& attributes) const
{
Structure* structure = this->structure(vm);
PropertyOffset offset = structure->get(vm, propertyName, attributes);
checkOffset(offset, structure->inlineCapacity());
return offset != invalidOffset ? getDirect(offset) : JSValue();
}
PropertyOffset getDirectOffset(VM& vm, PropertyName propertyName)
{
Structure* structure = this->structure(vm);
PropertyOffset offset = structure->get(vm, propertyName);
checkOffset(offset, structure->inlineCapacity());
return offset;
}
PropertyOffset getDirectOffset(VM& vm, PropertyName propertyName, unsigned& attributes)
{
Structure* structure = this->structure(vm);
PropertyOffset offset = structure->get(vm, propertyName, attributes);
checkOffset(offset, structure->inlineCapacity());
return offset;
}
bool hasInlineStorage() const { return structure()->hasInlineStorage(); }
ConstPropertyStorage inlineStorageUnsafe() const
{
return bitwise_cast<ConstPropertyStorage>(this + 1);
}
PropertyStorage inlineStorageUnsafe()
{
return bitwise_cast<PropertyStorage>(this + 1);
}
ConstPropertyStorage inlineStorage() const
{
ASSERT(hasInlineStorage());
return inlineStorageUnsafe();
}
PropertyStorage inlineStorage()
{
ASSERT(hasInlineStorage());
return inlineStorageUnsafe();
}
const Butterfly* butterfly() const { return m_butterfly.get(); }
Butterfly* butterfly() { return m_butterfly.get(); }
ConstPropertyStorage outOfLineStorage() const { return m_butterfly->propertyStorage(); }
PropertyStorage outOfLineStorage() { return m_butterfly->propertyStorage(); }
ALWAYS_INLINE const WriteBarrierBase<Unknown>* locationForOffset(PropertyOffset offset) const
{
if (isInlineOffset(offset))
return &inlineStorage()[offsetInInlineStorage(offset)];
return &outOfLineStorage()[offsetInOutOfLineStorage(offset)];
}
ALWAYS_INLINE WriteBarrierBase<Unknown>* locationForOffset(PropertyOffset offset)
{
if (isInlineOffset(offset))
return &inlineStorage()[offsetInInlineStorage(offset)];
return &outOfLineStorage()[offsetInOutOfLineStorage(offset)];
}
void transitionTo(VM&, Structure*);
bool hasCustomProperties(VM& vm) { return structure(vm)->didTransition(); }
bool hasGetterSetterProperties(VM& vm) { return structure(vm)->hasGetterSetterProperties(); }
bool hasCustomGetterSetterProperties(VM& vm) { return structure(vm)->hasCustomGetterSetterProperties(); }
// putOwnDataProperty has 'put' like semantics, however this method:
// - assumes the object contains no own getter/setter properties.
// - provides no special handling for __proto__
// - does not walk the prototype chain (to check for accessors or non-writable properties).
// This is used by JSLexicalEnvironment.
bool putOwnDataProperty(VM&, PropertyName, JSValue, PutPropertySlot&);
bool putOwnDataPropertyMayBeIndex(ExecState*, PropertyName, JSValue, PutPropertySlot&);
private:
void validatePutOwnDataProperty(VM&, PropertyName, JSValue);
public:
// Fast access to known property offsets.
ALWAYS_INLINE JSValue getDirect(PropertyOffset offset) const { return locationForOffset(offset)->get(); }
JSValue getDirectConcurrently(Structure* expectedStructure, PropertyOffset) const;
void putDirect(VM& vm, PropertyOffset offset, JSValue value) { locationForOffset(offset)->set(vm, this, value); }
void putDirectWithoutBarrier(PropertyOffset offset, JSValue value) { locationForOffset(offset)->setWithoutWriteBarrier(value); }
void putDirectUndefined(PropertyOffset offset) { locationForOffset(offset)->setUndefined(); }
JS_EXPORT_PRIVATE bool putDirectNativeIntrinsicGetter(VM&, JSGlobalObject*, Identifier, NativeFunction, Intrinsic, unsigned attributes);
JS_EXPORT_PRIVATE void putDirectNativeIntrinsicGetterWithoutTransition(VM&, JSGlobalObject*, Identifier, NativeFunction, Intrinsic, unsigned attributes);
JS_EXPORT_PRIVATE bool putDirectNativeFunction(VM&, JSGlobalObject*, const PropertyName&, unsigned functionLength, NativeFunction, Intrinsic, unsigned attributes);
JS_EXPORT_PRIVATE bool putDirectNativeFunction(VM&, JSGlobalObject*, const PropertyName&, unsigned functionLength, NativeFunction, Intrinsic, const DOMJIT::Signature*, unsigned attributes);
JS_EXPORT_PRIVATE void putDirectNativeFunctionWithoutTransition(VM&, JSGlobalObject*, const PropertyName&, unsigned functionLength, NativeFunction, Intrinsic, unsigned attributes);
JS_EXPORT_PRIVATE JSFunction* putDirectBuiltinFunction(VM&, JSGlobalObject*, const PropertyName&, FunctionExecutable*, unsigned attributes);
JSFunction* putDirectBuiltinFunctionWithoutTransition(VM&, JSGlobalObject*, const PropertyName&, FunctionExecutable*, unsigned attributes);
JS_EXPORT_PRIVATE static bool defineOwnProperty(JSObject*, ExecState*, PropertyName, const PropertyDescriptor&, bool shouldThrow);
bool isEnvironment() const;
bool isGlobalObject() const;
bool isJSLexicalEnvironment() const;
bool isGlobalLexicalEnvironment() const;
bool isStrictEvalActivation() const;
bool isWithScope() const;
bool isErrorInstance() const;
JS_EXPORT_PRIVATE void seal(VM&);
JS_EXPORT_PRIVATE void freeze(VM&);
JS_EXPORT_PRIVATE static bool preventExtensions(JSObject*, ExecState*);
JS_EXPORT_PRIVATE static bool isExtensible(JSObject*, ExecState*);
bool isSealed(VM& vm) { return structure(vm)->isSealed(vm); }
bool isFrozen(VM& vm) { return structure(vm)->isFrozen(vm); }
JS_EXPORT_PRIVATE bool anyObjectInChainMayInterceptIndexedAccesses(VM&) const;
JS_EXPORT_PRIVATE bool prototypeChainMayInterceptStoreTo(VM&, PropertyName);
bool needsSlowPutIndexing(VM&) const;
private:
NonPropertyTransition suggestedArrayStorageTransition(VM&) const;
public:
// You should only call isStructureExtensible() when:
// - Performing this check in a way that isn't described in the specification
// as calling the virtual [[IsExtensible]] trap.
// - When you're guaranteed that object->methodTable(vm)->isExtensible isn't
// overridden.
ALWAYS_INLINE bool isStructureExtensible(VM& vm) { return structure(vm)->isStructureExtensible(); }
// You should call this when performing [[IsExtensible]] trap in a place
// that is described in the specification. This performs the fully virtual
// [[IsExtensible]] trap.
bool isExtensible(ExecState*);
bool indexingShouldBeSparse(VM& vm)
{
return !isStructureExtensible(vm)
|| structure(vm)->typeInfo().interceptsGetOwnPropertySlotByIndexEvenWhenLengthIsNotZero();
}
bool staticPropertiesReified(VM& vm) { return structure(vm)->staticPropertiesReified(); }
void reifyAllStaticProperties(ExecState*);
JS_EXPORT_PRIVATE Butterfly* allocateMoreOutOfLineStorage(VM&, size_t oldSize, size_t newSize);
// Call this when you do not need to change the structure.
void setButterfly(VM&, Butterfly*);
// Call this if you do need to change the structure, or if you changed something about a structure
// in-place.
void nukeStructureAndSetButterfly(VM&, StructureID oldStructureID, Butterfly*);
void setStructure(VM&, Structure*);
JS_EXPORT_PRIVATE void convertToDictionary(VM&);
void flattenDictionaryObject(VM& vm)
{
structure(vm)->flattenDictionaryStructure(vm, this);
}
void shiftButterflyAfterFlattening(const GCSafeConcurrentJSLocker&, VM&, Structure* structure, size_t outOfLineCapacityAfter);
JSGlobalObject* globalObject() const
{
ASSERT(structure()->globalObject());
ASSERT(!isGlobalObject() || ((JSObject*)structure()->globalObject()) == this);
return structure()->globalObject();
}
JSGlobalObject* globalObject(VM& vm) const
{
ASSERT(structure(vm)->globalObject());
ASSERT(!isGlobalObject() || ((JSObject*)structure(vm)->globalObject()) == this);
return structure(vm)->globalObject();
}
void switchToSlowPutArrayStorage(VM&);
// The receiver is the prototype in this case. The following:
//
// asObject(foo->structure()->storedPrototype())->attemptToInterceptPutByIndexOnHoleForPrototype(...)
//
// is equivalent to:
//
// foo->attemptToInterceptPutByIndexOnHole(...);
bool attemptToInterceptPutByIndexOnHoleForPrototype(ExecState*, JSValue thisValue, unsigned propertyName, JSValue, bool shouldThrow, bool& putResult);
// Returns 0 if int32 storage cannot be created - either because
// indexing should be sparse, we're having a bad time, or because
// we already have a more general form of storage (double,
// contiguous, array storage).
ContiguousJSValues tryMakeWritableInt32(VM& vm)
{
if (LIKELY(hasInt32(indexingType()) && !isCopyOnWrite(indexingMode())))
return m_butterfly->contiguousInt32();
return tryMakeWritableInt32Slow(vm);
}
// Returns 0 if double storage cannot be created - either because
// indexing should be sparse, we're having a bad time, or because
// we already have a more general form of storage (contiguous,
// or array storage).
ContiguousDoubles tryMakeWritableDouble(VM& vm)
{
if (LIKELY(hasDouble(indexingType()) && !isCopyOnWrite(indexingMode())))
return m_butterfly->contiguousDouble();
return tryMakeWritableDoubleSlow(vm);
}
// Returns 0 if contiguous storage cannot be created - either because
// indexing should be sparse or because we're having a bad time.
ContiguousJSValues tryMakeWritableContiguous(VM& vm)
{
if (LIKELY(hasContiguous(indexingType()) && !isCopyOnWrite(indexingMode())))
return m_butterfly->contiguous();
return tryMakeWritableContiguousSlow(vm);
}
// Ensure that the object is in a mode where it has array storage. Use
// this if you're about to perform actions that would have required the
// object to be converted to have array storage, if it didn't have it
// already.
ArrayStorage* ensureArrayStorage(VM& vm)
{
if (LIKELY(hasAnyArrayStorage(indexingType())))
return m_butterfly->arrayStorage();
return ensureArrayStorageSlow(vm);
}
void ensureWritable(VM& vm)
{
if (isCopyOnWrite(indexingMode()))
convertFromCopyOnWrite(vm);
}
static size_t offsetOfInlineStorage();
static ptrdiff_t butterflyOffset()
{
return OBJECT_OFFSETOF(JSObject, m_butterfly);
}
void* butterflyAddress()
{
return &m_butterfly;
}
JS_EXPORT_PRIVATE JSValue getMethod(ExecState*, CallData&, CallType&, const Identifier&, const String& errorMessage);
bool canPerformFastPutInline(VM&, PropertyName);
bool canPerformFastPutInlineExcludingProto(VM&);
bool mayBePrototype() const;
void didBecomePrototype();
Optional<Structure::PropertyHashEntry> findPropertyHashEntry(VM&, PropertyName) const;
DECLARE_EXPORT_INFO;
protected:
void finishCreation(VM& vm)
{
Base::finishCreation(vm);
ASSERT(jsDynamicCast<JSObject*>(vm, this));
ASSERT(structure(vm)->hasPolyProto() || getPrototypeDirect(vm).isNull() || Heap::heap(this) == Heap::heap(getPrototypeDirect(vm)));
ASSERT(structure(vm)->isObject());
ASSERT(classInfo(vm));
}
static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype)
{
return Structure::create(vm, globalObject, prototype, TypeInfo(ObjectType, StructureFlags), info());
}
// To instantiate objects you likely want JSFinalObject, below.
// To create derived types you likely want JSNonFinalObject, below.
JSObject(VM&, Structure*, Butterfly* = nullptr);
// Visits the butterfly unless there is a race. Returns the structure if there was no race.
Structure* visitButterfly(SlotVisitor&);
Structure* visitButterflyImpl(SlotVisitor&);
void markAuxiliaryAndVisitOutOfLineProperties(SlotVisitor&, Butterfly*, Structure*, PropertyOffset lastOffset);
// Call this if you know that the object is in a mode where it has array
// storage. This will assert otherwise.
ArrayStorage* arrayStorage()
{
ASSERT(hasAnyArrayStorage(indexingType()));
return m_butterfly->arrayStorage();
}
// Call this if you want to predicate some actions on whether or not the
// object is in a mode where it has array storage.
ArrayStorage* arrayStorageOrNull()
{
switch (indexingType()) {
case ALL_ARRAY_STORAGE_INDEXING_TYPES:
return m_butterfly->arrayStorage();
default:
return 0;
}
}
size_t butterflyTotalSize();
size_t butterflyPreCapacity();
Butterfly* createInitialUndecided(VM&, unsigned length);
ContiguousJSValues createInitialInt32(VM&, unsigned length);
ContiguousDoubles createInitialDouble(VM&, unsigned length);
ContiguousJSValues createInitialContiguous(VM&, unsigned length);
void convertUndecidedForValue(VM&, JSValue);
void createInitialForValueAndSet(VM&, unsigned index, JSValue);
void convertInt32ForValue(VM&, JSValue);
void convertDoubleForValue(VM&, JSValue);
void convertFromCopyOnWrite(VM&);
static Butterfly* createArrayStorageButterfly(VM&, JSObject* intendedOwner, Structure*, unsigned length, unsigned vectorLength, Butterfly* oldButterfly = nullptr);
ArrayStorage* createArrayStorage(VM&, unsigned length, unsigned vectorLength);
ArrayStorage* createInitialArrayStorage(VM&);
ContiguousJSValues convertUndecidedToInt32(VM&);
ContiguousDoubles convertUndecidedToDouble(VM&);
ContiguousJSValues convertUndecidedToContiguous(VM&);
ArrayStorage* convertUndecidedToArrayStorage(VM&, NonPropertyTransition);
ArrayStorage* convertUndecidedToArrayStorage(VM&);
ContiguousDoubles convertInt32ToDouble(VM&);
ContiguousJSValues convertInt32ToContiguous(VM&);
ArrayStorage* convertInt32ToArrayStorage(VM&, NonPropertyTransition);
ArrayStorage* convertInt32ToArrayStorage(VM&);
ContiguousJSValues convertDoubleToContiguous(VM&);
ArrayStorage* convertDoubleToArrayStorage(VM&, NonPropertyTransition);
ArrayStorage* convertDoubleToArrayStorage(VM&);
ArrayStorage* convertContiguousToArrayStorage(VM&, NonPropertyTransition);
ArrayStorage* convertContiguousToArrayStorage(VM&);
ArrayStorage* ensureArrayStorageExistsAndEnterDictionaryIndexingMode(VM&);
bool defineOwnNonIndexProperty(ExecState*, PropertyName, const PropertyDescriptor&, bool throwException);
template<IndexingType indexingShape>
bool putByIndexBeyondVectorLengthWithoutAttributes(ExecState*, unsigned propertyName, JSValue);
bool putByIndexBeyondVectorLengthWithArrayStorage(ExecState*, unsigned propertyName, JSValue, bool shouldThrow, ArrayStorage*);
bool increaseVectorLength(VM&, unsigned newLength);
void deallocateSparseIndexMap();
bool defineOwnIndexedProperty(ExecState*, unsigned, const PropertyDescriptor&, bool throwException);
SparseArrayValueMap* allocateSparseIndexMap(VM&);
void notifyPresenceOfIndexedAccessors(VM&);
bool attemptToInterceptPutByIndexOnHole(ExecState*, unsigned index, JSValue, bool shouldThrow, bool& putResult);
// Call this if you want setIndexQuickly to succeed and you're sure that
// the array is contiguous.
bool WARN_UNUSED_RETURN ensureLength(VM& vm, unsigned length)
{
RELEASE_ASSERT(length <= MAX_STORAGE_VECTOR_LENGTH);
ASSERT(hasContiguous(indexingType()) || hasInt32(indexingType()) || hasDouble(indexingType()) || hasUndecided(indexingType()));
if (m_butterfly->vectorLength() < length || isCopyOnWrite(indexingMode())) {
if (!ensureLengthSlow(vm, length))
return false;
}
if (m_butterfly->publicLength() < length)
m_butterfly->setPublicLength(length);
return true;
}
// Call this if you want to shrink the butterfly backing store, and you're
// sure that the array is contiguous.
void reallocateAndShrinkButterfly(VM&, unsigned length);
template<IndexingType indexingShape>
unsigned countElements(Butterfly*);
// This is relevant to undecided, int32, double, and contiguous.
unsigned countElements();
private:
friend class LLIntOffsetsExtractor;
friend class VMInspector;
// Nobody should ever ask any of these questions on something already known to be a JSObject.
using JSCell::isAPIValueWrapper;
using JSCell::isGetterSetter;
void getObject();
void getString(ExecState* exec);
void isObject();
void isString();
Butterfly* createInitialIndexedStorage(VM&, unsigned length);
ArrayStorage* enterDictionaryIndexingModeWhenArrayStorageAlreadyExists(VM&, ArrayStorage*);
template<PutMode>
bool putDirectInternal(VM&, PropertyName, JSValue, unsigned attr, PutPropertySlot&);
JS_EXPORT_PRIVATE NEVER_INLINE bool putInlineSlow(ExecState*, PropertyName, JSValue, PutPropertySlot&);
bool getNonIndexPropertySlot(ExecState*, PropertyName, PropertySlot&);
bool getOwnNonIndexPropertySlot(VM&, Structure*, PropertyName, PropertySlot&);
JS_EXPORT_PRIVATE void fillGetterPropertySlot(VM&, PropertySlot&, JSCell*, unsigned, PropertyOffset);
void fillCustomGetterPropertySlot(VM&, PropertySlot&, CustomGetterSetter*, unsigned, Structure*);
JS_EXPORT_PRIVATE bool getOwnStaticPropertySlot(VM&, PropertyName, PropertySlot&);
bool putByIndexBeyondVectorLength(ExecState*, unsigned propertyName, JSValue, bool shouldThrow);
bool putDirectIndexBeyondVectorLengthWithArrayStorage(ExecState*, unsigned propertyName, JSValue, unsigned attributes, PutDirectIndexMode, ArrayStorage*);
JS_EXPORT_PRIVATE bool putDirectIndexSlowOrBeyondVectorLength(ExecState*, unsigned propertyName, JSValue, unsigned attributes, PutDirectIndexMode);
unsigned getNewVectorLength(VM&, unsigned indexBias, unsigned currentVectorLength, unsigned currentLength, unsigned desiredLength);
unsigned getNewVectorLength(VM&, unsigned desiredLength);
ArrayStorage* constructConvertedArrayStorageWithoutCopyingElements(VM&, unsigned neededLength);
JS_EXPORT_PRIVATE void setIndexQuicklyToUndecided(VM&, unsigned index, JSValue);
JS_EXPORT_PRIVATE void convertInt32ToDoubleOrContiguousWhilePerformingSetIndex(VM&, unsigned index, JSValue);
JS_EXPORT_PRIVATE void convertDoubleToContiguousWhilePerformingSetIndex(VM&, unsigned index, JSValue);
bool ensureLengthSlow(VM&, unsigned length);
ContiguousJSValues tryMakeWritableInt32Slow(VM&);
ContiguousDoubles tryMakeWritableDoubleSlow(VM&);
ContiguousJSValues tryMakeWritableContiguousSlow(VM&);
JS_EXPORT_PRIVATE ArrayStorage* ensureArrayStorageSlow(VM&);
PropertyOffset prepareToPutDirectWithoutTransition(VM&, PropertyName, unsigned attributes, StructureID, Structure*);
AuxiliaryBarrier<Butterfly*> m_butterfly;
#if CPU(ADDRESS32)
unsigned m_32BitPadding;
#endif
};
// JSNonFinalObject is a type of JSObject that has some internal storage,
// but also preserves some space in the collector cell for additional
// data members in derived types.
class JSNonFinalObject : public JSObject {
friend class JSObject;
public:
typedef JSObject Base;
static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype)
{
return Structure::create(vm, globalObject, prototype, TypeInfo(ObjectType, StructureFlags), info());
}
protected:
explicit JSNonFinalObject(VM& vm, Structure* structure, Butterfly* butterfly = 0)
: JSObject(vm, structure, butterfly)
{
}
void finishCreation(VM& vm)
{
Base::finishCreation(vm);
ASSERT(!this->structure(vm)->hasInlineStorage());
ASSERT(classInfo(vm));
}
};
class JSFinalObject;
// JSFinalObject is a type of JSObject that contains sufficient internal
// storage to fully make use of the collector cell containing it.
class JSFinalObject final : public JSObject {
friend class JSObject;
public:
typedef JSObject Base;
static constexpr unsigned StructureFlags = Base::StructureFlags;
static size_t allocationSize(Checked<size_t> inlineCapacity)
{
return (sizeof(JSObject) + inlineCapacity * sizeof(WriteBarrierBase<Unknown>)).unsafeGet();
}
static inline const TypeInfo typeInfo() { return TypeInfo(FinalObjectType, StructureFlags); }
static constexpr IndexingType defaultIndexingType = NonArray;
static constexpr unsigned defaultSize = 64;
static inline unsigned defaultInlineCapacity()
{
return (defaultSize - allocationSize(0)) / sizeof(WriteBarrier<Unknown>);
}
static constexpr unsigned maxSize = 512;
static inline unsigned maxInlineCapacity()
{
return (maxSize - allocationSize(0)) / sizeof(WriteBarrier<Unknown>);
}
static JSFinalObject* create(ExecState*, Structure*, Butterfly* = nullptr);
static JSFinalObject* create(VM&, Structure*);
static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype, unsigned inlineCapacity)
{
return Structure::create(vm, globalObject, prototype, typeInfo(), info(), defaultIndexingType, inlineCapacity);
}
JS_EXPORT_PRIVATE static void visitChildren(JSCell*, SlotVisitor&);
DECLARE_EXPORT_INFO;
protected:
void visitChildrenCommon(SlotVisitor&);
void finishCreation(VM& vm)
{
Base::finishCreation(vm);
ASSERT(structure(vm)->totalStorageCapacity() == structure(vm)->inlineCapacity());
ASSERT(classInfo(vm));
}
private:
friend class LLIntOffsetsExtractor;
explicit JSFinalObject(VM& vm, Structure* structure, Butterfly* butterfly = nullptr)
: JSObject(vm, structure, butterfly)
{
memset(inlineStorageUnsafe(), 0, structure->inlineCapacity() * sizeof(EncodedJSValue));
}
};
JS_EXPORT_PRIVATE EncodedJSValue JSC_HOST_CALL objectPrivateFuncInstanceOf(JSGlobalObject*, CallFrame*);
inline JSObject* JSObject::createRawObject(
ExecState* exec, Structure* structure, Butterfly* butterfly)
{
VM& vm = exec->vm();
JSObject* finalObject = new (
NotNull,
allocateCell<JSFinalObject>(
vm.heap,
JSFinalObject::allocationSize(structure->inlineCapacity())
)
) JSObject(vm, structure, butterfly);
finalObject->finishCreation(vm);
return finalObject;
}
inline JSFinalObject* JSFinalObject::create(
ExecState* exec, Structure* structure, Butterfly* butterfly)
{
VM& vm = exec->vm();
JSFinalObject* finalObject = new (
NotNull,
allocateCell<JSFinalObject>(
vm.heap,
allocationSize(structure->inlineCapacity())
)
) JSFinalObject(vm, structure, butterfly);
finalObject->finishCreation(vm);
return finalObject;
}
inline JSFinalObject* JSFinalObject::create(VM& vm, Structure* structure)
{
JSFinalObject* finalObject = new (NotNull, allocateCell<JSFinalObject>(vm.heap, allocationSize(structure->inlineCapacity()))) JSFinalObject(vm, structure);
finalObject->finishCreation(vm);
return finalObject;
}
inline size_t JSObject::offsetOfInlineStorage()
{
return sizeof(JSObject);
}
inline bool JSObject::isGlobalObject() const
{
return type() == GlobalObjectType;
}
inline bool JSObject::isJSLexicalEnvironment() const
{
return type() == LexicalEnvironmentType || type() == ModuleEnvironmentType;
}
inline bool JSObject::isGlobalLexicalEnvironment() const
{
return type() == GlobalLexicalEnvironmentType;
}
inline bool JSObject::isStrictEvalActivation() const
{
return type() == StrictEvalActivationType;
}
inline bool JSObject::isEnvironment() const
{
bool result = GlobalObjectType <= type() && type() <= StrictEvalActivationType;
ASSERT((isGlobalObject() || isJSLexicalEnvironment() || isGlobalLexicalEnvironment() || isStrictEvalActivation()) == result);
return result;
}
inline bool JSObject::isErrorInstance() const
{
return type() == ErrorInstanceType;
}
inline bool JSObject::isWithScope() const
{
return type() == WithScopeType;
}
inline void JSObject::setStructure(VM& vm, Structure* structure)
{
ASSERT(structure);
ASSERT(!m_butterfly == !(structure->outOfLineCapacity() || structure->hasIndexingHeader(this)));
JSCell::setStructure(vm, structure);
}
inline void JSObject::setButterfly(VM& vm, Butterfly* butterfly)
{
if (isX86() || vm.heap.mutatorShouldBeFenced()) {
WTF::storeStoreFence();
m_butterfly.set(vm, this, butterfly);
WTF::storeStoreFence();
return;
}
m_butterfly.set(vm, this, butterfly);
}
inline void JSObject::nukeStructureAndSetButterfly(VM& vm, StructureID oldStructureID, Butterfly* butterfly)
{
if (isX86() || vm.heap.mutatorShouldBeFenced()) {
setStructureIDDirectly(nuke(oldStructureID));
WTF::storeStoreFence();
m_butterfly.set(vm, this, butterfly);
WTF::storeStoreFence();
return;
}
m_butterfly.set(vm, this, butterfly);
}
inline CallType getCallData(VM& vm, JSValue value, CallData& callData)
{
CallType result = value.isCell() ? value.asCell()->methodTable(vm)->getCallData(value.asCell(), callData) : CallType::None;
ASSERT(result == CallType::None || value.isValidCallee());
return result;
}
inline ConstructType getConstructData(VM& vm, JSValue value, ConstructData& constructData)
{
ConstructType result = value.isCell() ? value.asCell()->methodTable(vm)->getConstructData(value.asCell(), constructData) : ConstructType::None;
ASSERT(result == ConstructType::None || value.isValidCallee());
return result;
}
inline JSObject* asObject(JSCell* cell)
{
ASSERT(cell->isObject());
return jsCast<JSObject*>(cell);
}
inline JSObject* asObject(JSValue value)
{
return asObject(value.asCell());
}
inline JSObject::JSObject(VM& vm, Structure* structure, Butterfly* butterfly)
: JSCell(vm, structure)
, m_butterfly(vm, this, butterfly)
{
}
inline JSValue JSObject::getPrototypeDirect(VM& vm) const
{
return structure(vm)->storedPrototype(this);
}
inline JSValue JSObject::getPrototype(VM& vm, ExecState* exec)
{
auto getPrototypeMethod = methodTable(vm)->getPrototype;
MethodTable::GetPrototypeFunctionPtr defaultGetPrototype = JSObject::getPrototype;
if (LIKELY(getPrototypeMethod == defaultGetPrototype))
return getPrototypeDirect(vm);
return getPrototypeMethod(this, exec);
}
// Normally, we never shrink the butterfly so if we know an offset is valid for some
// past structure then it should be valid for any new structure. However, we may sometimes
// shrink the butterfly when we are holding the Structure's ConcurrentJSLock, such as when we
// flatten an object.
inline JSValue JSObject::getDirectConcurrently(Structure* structure, PropertyOffset offset) const
{
ConcurrentJSLocker locker(structure->lock());
if (!structure->isValidOffset(offset))
return { };
return getDirect(offset);
}
// It is safe to call this method with a PropertyName that is actually an index,
// but if so will always return false (doesn't search index storage).
ALWAYS_INLINE bool JSObject::getOwnNonIndexPropertySlot(VM& vm, Structure* structure, PropertyName propertyName, PropertySlot& slot)
{
unsigned attributes;
PropertyOffset offset = structure->get(vm, propertyName, attributes);
if (!isValidOffset(offset)) {
if (!TypeInfo::hasStaticPropertyTable(inlineTypeFlags()))
return false;
return getOwnStaticPropertySlot(vm, propertyName, slot);
}
// getPropertySlot relies on this method never returning index properties!
ASSERT(!parseIndex(propertyName));
JSValue value = getDirect(offset);
if (value.isCell()) {
ASSERT(value);
JSCell* cell = value.asCell();
JSType type = cell->type();
switch (type) {
case GetterSetterType:
fillGetterPropertySlot(vm, slot, cell, attributes, offset);
return true;
case CustomGetterSetterType:
fillCustomGetterPropertySlot(vm, slot, jsCast<CustomGetterSetter*>(cell), attributes, structure);
return true;
default:
break;
}
}
slot.setValue(this, attributes, value, offset);
return true;
}
ALWAYS_INLINE void JSObject::fillCustomGetterPropertySlot(VM& vm, PropertySlot& slot, CustomGetterSetter* customGetterSetter, unsigned attributes, Structure* structure)
{
ASSERT(attributes & PropertyAttribute::CustomAccessorOrValue);
if (customGetterSetter->inherits<DOMAttributeGetterSetter>(vm)) {
auto* domAttribute = jsCast<DOMAttributeGetterSetter*>(customGetterSetter);
if (structure->isUncacheableDictionary())
slot.setCustom(this, attributes, domAttribute->getter(), domAttribute->domAttribute());
else
slot.setCacheableCustom(this, attributes, domAttribute->getter(), domAttribute->domAttribute());
return;
}
if (structure->isUncacheableDictionary())
slot.setCustom(this, attributes, customGetterSetter->getter());
else
slot.setCacheableCustom(this, attributes, customGetterSetter->getter());
}
// It may seem crazy to inline a function this large, especially a virtual function,
// but it makes a big difference to property lookup that derived classes can inline their
// base class call to this.
ALWAYS_INLINE bool JSObject::getOwnPropertySlot(JSObject* object, ExecState* exec, PropertyName propertyName, PropertySlot& slot)
{
VM& vm = exec->vm();
Structure* structure = object->structure(vm);
if (object->getOwnNonIndexPropertySlot(vm, structure, propertyName, slot))
return true;
if (Optional<uint32_t> index = parseIndex(propertyName))
return getOwnPropertySlotByIndex(object, exec, index.value(), slot);
return false;
}
ALWAYS_INLINE void JSObject::doPutPropertySecurityCheck(JSObject*, ExecState*, PropertyName, PutPropertySlot&)
{
}
// It may seem crazy to inline a function this large but it makes a big difference
// since this is function very hot in variable lookup
template<bool checkNullStructure>
ALWAYS_INLINE bool JSObject::getPropertySlot(ExecState* exec, PropertyName propertyName, PropertySlot& slot)
{
VM& vm = exec->vm();
auto& structureIDTable = vm.heap.structureIDTable();
JSObject* object = this;
while (true) {
if (UNLIKELY(TypeInfo::overridesGetOwnPropertySlot(object->inlineTypeFlags()))) {
// If propertyName is an index then we may have missed it (as this loop is using
// getOwnNonIndexPropertySlot), so we cannot safely call the overridden getOwnPropertySlot
// (lest we return a property from a prototype that is shadowed). Check now for an index,
// if so we need to start afresh from this object.
if (Optional<uint32_t> index = parseIndex(propertyName))
return getPropertySlot(exec, index.value(), slot);
// Safe to continue searching from current position; call getNonIndexPropertySlot to avoid
// parsing the int again.
return object->getNonIndexPropertySlot(exec, propertyName, slot);
}
ASSERT(object->type() != ProxyObjectType);
Structure* structure = structureIDTable.get(object->structureID());
#if USE(JSVALUE64)
if (checkNullStructure && UNLIKELY(!structure))
CRASH_WITH_INFO(object->type(), object->structureID(), structureIDTable.size());
#endif
if (object->getOwnNonIndexPropertySlot(vm, structure, propertyName, slot))
return true;
// FIXME: This doesn't look like it's following the specification:
// https://bugs.webkit.org/show_bug.cgi?id=172572
JSValue prototype = structure->storedPrototype(object);
if (!prototype.isObject())
break;
object = asObject(prototype);
}
if (Optional<uint32_t> index = parseIndex(propertyName))
return getPropertySlot(exec, index.value(), slot);
return false;
}
inline JSValue JSObject::get(ExecState* exec, PropertyName propertyName) const
{
VM& vm = exec->vm();
auto scope = DECLARE_THROW_SCOPE(vm);
PropertySlot slot(this, PropertySlot::InternalMethodType::Get);
bool hasProperty = const_cast<JSObject*>(this)->getPropertySlot(exec, propertyName, slot);
EXCEPTION_ASSERT(!scope.exception() || !hasProperty);
if (hasProperty)
RELEASE_AND_RETURN(scope, slot.getValue(exec, propertyName));
return jsUndefined();
}
inline JSValue JSObject::get(ExecState* exec, unsigned propertyName) const
{
VM& vm = exec->vm();
auto scope = DECLARE_THROW_SCOPE(vm);
PropertySlot slot(this, PropertySlot::InternalMethodType::Get);
bool hasProperty = const_cast<JSObject*>(this)->getPropertySlot(exec, propertyName, slot);
EXCEPTION_ASSERT(!scope.exception() || !hasProperty);
if (hasProperty)
RELEASE_AND_RETURN(scope, slot.getValue(exec, propertyName));
return jsUndefined();
}
inline bool JSObject::putDirect(VM& vm, PropertyName propertyName, JSValue value, unsigned attributes)
{
ASSERT(!value.isGetterSetter() && !(attributes & PropertyAttribute::Accessor));
ASSERT(!value.isCustomGetterSetter() && !(attributes & PropertyAttribute::CustomAccessorOrValue));
PutPropertySlot slot(this);
return putDirectInternal<PutModeDefineOwnProperty>(vm, propertyName, value, attributes, slot);
}
inline bool JSObject::putDirect(VM& vm, PropertyName propertyName, JSValue value, PutPropertySlot& slot)
{
ASSERT(!value.isGetterSetter());
ASSERT(!value.isCustomGetterSetter());
return putDirectInternal<PutModeDefineOwnProperty>(vm, propertyName, value, 0, slot);
}
ALWAYS_INLINE JSObject* Register::object() const
{
return asObject(jsValue());
}
ALWAYS_INLINE Register& Register::operator=(JSObject* object)
{
u.value = JSValue::encode(JSValue(object));
return *this;
}
inline size_t offsetInButterfly(PropertyOffset offset)
{
return offsetInOutOfLineStorage(offset) + Butterfly::indexOfPropertyStorage();
}
inline size_t JSObject::butterflyPreCapacity()
{
VM& vm = this->vm();
if (UNLIKELY(hasIndexingHeader(vm)))
return butterfly()->indexingHeader()->preCapacity(structure(vm));
return 0;
}
inline size_t JSObject::butterflyTotalSize()
{
VM& vm = this->vm();
Structure* structure = this->structure(vm);
Butterfly* butterfly = this->butterfly();
size_t preCapacity;
size_t indexingPayloadSizeInBytes;
bool hasIndexingHeader = this->hasIndexingHeader(vm);
if (UNLIKELY(hasIndexingHeader)) {
preCapacity = butterfly->indexingHeader()->preCapacity(structure);
indexingPayloadSizeInBytes = butterfly->indexingHeader()->indexingPayloadSizeInBytes(structure);
} else {
preCapacity = 0;
indexingPayloadSizeInBytes = 0;
}
return Butterfly::totalSize(preCapacity, structure->outOfLineCapacity(), hasIndexingHeader, indexingPayloadSizeInBytes);
}
inline int indexRelativeToBase(PropertyOffset offset)
{
if (isOutOfLineOffset(offset))
return offsetInOutOfLineStorage(offset) + Butterfly::indexOfPropertyStorage();
ASSERT(!(JSObject::offsetOfInlineStorage() % sizeof(EncodedJSValue)));
return JSObject::offsetOfInlineStorage() / sizeof(EncodedJSValue) + offsetInInlineStorage(offset);
}
inline int offsetRelativeToBase(PropertyOffset offset)
{
if (isOutOfLineOffset(offset))
return offsetInOutOfLineStorage(offset) * sizeof(EncodedJSValue) + Butterfly::offsetOfPropertyStorage();
return JSObject::offsetOfInlineStorage() + offsetInInlineStorage(offset) * sizeof(EncodedJSValue);
}
// Returns the maximum offset (away from zero) a load instruction will encode.
inline size_t maxOffsetRelativeToBase(PropertyOffset offset)
{
ptrdiff_t addressOffset = offsetRelativeToBase(offset);
#if USE(JSVALUE32_64)
if (addressOffset >= 0)
return static_cast<size_t>(addressOffset) + OBJECT_OFFSETOF(EncodedValueDescriptor, asBits.tag);
#endif
return static_cast<size_t>(addressOffset);
}
COMPILE_ASSERT(!(sizeof(JSObject) % sizeof(WriteBarrierBase<Unknown>)), JSObject_inline_storage_has_correct_alignment);
template<unsigned charactersCount>
ALWAYS_INLINE Identifier makeIdentifier(VM& vm, const char (&characters)[charactersCount])
{
return Identifier::fromString(vm, characters);
}
ALWAYS_INLINE Identifier makeIdentifier(VM& vm, const char* name)
{
return Identifier::fromString(vm, name);
}
ALWAYS_INLINE Identifier makeIdentifier(VM&, const Identifier& name)
{
return name;
}
bool validateAndApplyPropertyDescriptor(ExecState*, JSObject*, PropertyName, bool isExtensible,
const PropertyDescriptor& descriptor, bool isCurrentDefined, const PropertyDescriptor& current, bool throwException);
JS_EXPORT_PRIVATE NEVER_INLINE bool ordinarySetSlow(ExecState*, JSObject*, PropertyName, JSValue, JSValue receiver, bool shouldThrow);
// Helper for defining native functions, if you're not using a static hash table.
// Use this macro from within finishCreation() methods in prototypes. This assumes
// you've defined variables called exec, globalObject, and vm, and they
// have the expected meanings.
#define JSC_NATIVE_INTRINSIC_FUNCTION(jsName, cppName, attributes, length, intrinsic) \
putDirectNativeFunction(\
vm, globalObject, makeIdentifier(vm, (jsName)), (length), cppName, \
(intrinsic), (attributes))
#define JSC_NATIVE_INTRINSIC_FUNCTION_WITHOUT_TRANSITION(jsName, cppName, attributes, length, intrinsic) \
putDirectNativeFunctionWithoutTransition(\
vm, globalObject, makeIdentifier(vm, (jsName)), (length), cppName, \
(intrinsic), (attributes))
// As above, but this assumes that the function you're defining doesn't have an
// intrinsic.
#define JSC_NATIVE_FUNCTION(jsName, cppName, attributes, length) \
JSC_NATIVE_INTRINSIC_FUNCTION(jsName, cppName, (attributes), (length), NoIntrinsic)
#define JSC_NATIVE_FUNCTION_WITHOUT_TRANSITION(jsName, cppName, attributes, length) \
JSC_NATIVE_INTRINSIC_FUNCTION_WITHOUT_TRANSITION(jsName, cppName, (attributes), (length), NoIntrinsic)
// Identical helpers but for builtins. Note that currently, we don't support builtins that are
// also intrinsics, but we probably will do that eventually.
#define JSC_BUILTIN_FUNCTION(jsName, generatorName, attributes) \
putDirectBuiltinFunction(\
vm, globalObject, makeIdentifier(vm, (jsName)), (generatorName)(vm), (attributes))
#define JSC_BUILTIN_FUNCTION_WITHOUT_TRANSITION(jsName, generatorName, attributes) \
putDirectBuiltinFunctionWithoutTransition(\
vm, globalObject, makeIdentifier(vm, (jsName)), (generatorName)(vm), (attributes))
// Helper for defining native getters on properties.
#define JSC_NATIVE_INTRINSIC_GETTER(jsName, cppName, attributes, intrinsic) \
putDirectNativeIntrinsicGetter(\
vm, globalObject, makeIdentifier(vm, (jsName)), (cppName), \
(intrinsic), ((attributes) | PropertyAttribute::Accessor))
#define JSC_NATIVE_INTRINSIC_GETTER_WITHOUT_TRANSITION(jsName, cppName, attributes, intrinsic) \
putDirectNativeIntrinsicGetterWithoutTransition(\
vm, globalObject, makeIdentifier(vm, (jsName)), (cppName), \
(intrinsic), ((attributes) | PropertyAttribute::Accessor))
#define JSC_NATIVE_GETTER(jsName, cppName, attributes) \
JSC_NATIVE_INTRINSIC_GETTER((jsName), (cppName), (attributes), NoIntrinsic)
#define JSC_NATIVE_GETTER_WITHOUT_TRANSITION(jsName, cppName, attributes) \
JSC_NATIVE_INTRINSIC_GETTER_WITHOUT_TRANSITION((jsName), (cppName), (attributes), NoIntrinsic)
} // namespace JSC