/*
* Copyright (C) 1999-2001 Harri Porten (porten@kde.org)
* Copyright (C) 2001 Peter Kelly (pmk@post.com)
* Copyright (C) 2003, 2004, 2005, 2007, 2008, 2009 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.
*
*/
#ifndef JSCell_h
#define JSCell_h
#include "CallData.h"
#include "CallFrame.h"
#include "ConstructData.h"
#include "Heap.h"
#include "JSLock.h"
#include "JSValueInlineMethods.h"
#include "MarkStack.h"
#include <wtf/Noncopyable.h>
namespace JSC {
class JSGlobalObject;
class Structure;
#if COMPILER(MSVC)
// If WTF_MAKE_NONCOPYABLE is applied to JSCell we end up with a bunch of
// undefined references to the JSCell copy constructor and assignment operator
// when linking JavaScriptCore.
class MSVCBugWorkaround {
WTF_MAKE_NONCOPYABLE(MSVCBugWorkaround);
protected:
MSVCBugWorkaround() { }
~MSVCBugWorkaround() { }
};
class JSCell : MSVCBugWorkaround {
#else
class JSCell {
WTF_MAKE_NONCOPYABLE(JSCell);
#endif
friend class ExecutableBase;
friend class GetterSetter;
friend class Heap;
friend class JSObject;
friend class JSPropertyNameIterator;
friend class JSString;
friend class JSValue;
friend class JSAPIValueWrapper;
friend class JSZombie;
friend class JSGlobalData;
friend class MarkedSpace;
friend class MarkedBlock;
friend class ScopeChainNode;
friend class Structure;
friend class StructureChain;
protected:
enum VPtrStealingHackType { VPtrStealingHack };
private:
explicit JSCell(VPtrStealingHackType) { }
JSCell(JSGlobalData&, Structure*);
virtual ~JSCell();
public:
static Structure* createDummyStructure(JSGlobalData&);
// Querying the type.
bool isString() const;
bool isObject() const;
virtual bool isGetterSetter() const;
bool inherits(const ClassInfo*) const;
virtual bool isAPIValueWrapper() const { return false; }
virtual bool isPropertyNameIterator() const { return false; }
Structure* structure() const;
// Extracting the value.
bool getString(ExecState* exec, UString&) const;
UString getString(ExecState* exec) const; // null string if not a string
JSObject* getObject(); // NULL if not an object
const JSObject* getObject() const; // NULL if not an object
virtual CallType getCallData(CallData&);
virtual ConstructType getConstructData(ConstructData&);
// Extracting integer values.
// FIXME: remove these methods, can check isNumberCell in JSValue && then call asNumberCell::*.
virtual bool getUInt32(uint32_t&) const;
// Basic conversions.
virtual JSValue toPrimitive(ExecState*, PreferredPrimitiveType) const;
virtual bool getPrimitiveNumber(ExecState*, double& number, JSValue&);
virtual bool toBoolean(ExecState*) const;
virtual double toNumber(ExecState*) const;
virtual UString toString(ExecState*) const;
virtual JSObject* toObject(ExecState*, JSGlobalObject*) const;
// Garbage collection.
void* operator new(size_t, ExecState*);
void* operator new(size_t, JSGlobalData*);
void* operator new(size_t, void* placementNewDestination) { return placementNewDestination; }
virtual void markChildren(MarkStack&);
#if ENABLE(JSC_ZOMBIES)
virtual bool isZombie() const { return false; }
#endif
// Object operations, with the toObject operation included.
const ClassInfo* classInfo() const;
virtual void put(ExecState*, const Identifier& propertyName, JSValue, PutPropertySlot&);
virtual void put(ExecState*, unsigned propertyName, JSValue);
virtual bool deleteProperty(ExecState*, const Identifier& propertyName);
virtual bool deleteProperty(ExecState*, unsigned propertyName);
virtual JSObject* toThisObject(ExecState*) const;
virtual JSValue getJSNumber();
void* vptr() { return *reinterpret_cast<void**>(this); }
void setVPtr(void* vptr) { *reinterpret_cast<void**>(this) = vptr; }
// FIXME: Rename getOwnPropertySlot to virtualGetOwnPropertySlot, and
// fastGetOwnPropertySlot to getOwnPropertySlot. Callers should always
// call this function, not its slower virtual counterpart. (For integer
// property names, we want a similar interface with appropriate optimizations.)
bool fastGetOwnPropertySlot(ExecState*, const Identifier& propertyName, PropertySlot&);
static ptrdiff_t structureOffset()
{
return OBJECT_OFFSETOF(JSCell, m_structure);
}
const void* addressOfStructure() const
{
return &m_structure;
}
protected:
static const unsigned AnonymousSlotCount = 0;
private:
// Base implementation; for non-object classes implements getPropertySlot.
virtual bool getOwnPropertySlot(ExecState*, const Identifier& propertyName, PropertySlot&);
virtual bool getOwnPropertySlot(ExecState*, unsigned propertyName, PropertySlot&);
WriteBarrier<Structure> m_structure;
};
inline JSCell::JSCell(JSGlobalData& globalData, Structure* structure)
: m_structure(globalData, this, structure)
{
// Very first set of allocations won't have a real structure.
ASSERT(m_structure || !globalData.dummyMarkableCellStructure);
}
inline JSCell::~JSCell()
{
}
inline Structure* JSCell::structure() const
{
return m_structure.get();
}
inline void JSCell::markChildren(MarkStack& markStack)
{
markStack.append(&m_structure);
}
// --- JSValue inlines ----------------------------
inline bool JSValue::isString() const
{
return isCell() && asCell()->isString();
}
inline bool JSValue::isGetterSetter() const
{
return isCell() && asCell()->isGetterSetter();
}
inline bool JSValue::isObject() const
{
return isCell() && asCell()->isObject();
}
inline bool JSValue::getString(ExecState* exec, UString& s) const
{
return isCell() && asCell()->getString(exec, s);
}
inline UString JSValue::getString(ExecState* exec) const
{
return isCell() ? asCell()->getString(exec) : UString();
}
template <typename Base> UString HandleConverter<Base, Unknown>::getString(ExecState* exec) const
{
return jsValue().getString(exec);
}
inline JSObject* JSValue::getObject() const
{
return isCell() ? asCell()->getObject() : 0;
}
inline CallType getCallData(JSValue value, CallData& callData)
{
CallType result = value.isCell() ? value.asCell()->getCallData(callData) : CallTypeNone;
ASSERT(result == CallTypeNone || value.isValidCallee());
return result;
}
inline ConstructType getConstructData(JSValue value, ConstructData& constructData)
{
ConstructType result = value.isCell() ? value.asCell()->getConstructData(constructData) : ConstructTypeNone;
ASSERT(result == ConstructTypeNone || value.isValidCallee());
return result;
}
ALWAYS_INLINE bool JSValue::getUInt32(uint32_t& v) const
{
if (isInt32()) {
int32_t i = asInt32();
v = static_cast<uint32_t>(i);
return i >= 0;
}
if (isDouble()) {
double d = asDouble();
v = static_cast<uint32_t>(d);
return v == d;
}
return false;
}
inline JSValue JSValue::toPrimitive(ExecState* exec, PreferredPrimitiveType preferredType) const
{
return isCell() ? asCell()->toPrimitive(exec, preferredType) : asValue();
}
inline bool JSValue::getPrimitiveNumber(ExecState* exec, double& number, JSValue& value)
{
if (isInt32()) {
number = asInt32();
value = *this;
return true;
}
if (isDouble()) {
number = asDouble();
value = *this;
return true;
}
if (isCell())
return asCell()->getPrimitiveNumber(exec, number, value);
if (isTrue()) {
number = 1.0;
value = *this;
return true;
}
if (isFalse() || isNull()) {
number = 0.0;
value = *this;
return true;
}
ASSERT(isUndefined());
number = nonInlineNaN();
value = *this;
return true;
}
inline bool JSValue::toBoolean(ExecState* exec) const
{
if (isInt32())
return asInt32() != 0;
if (isDouble())
return asDouble() > 0.0 || asDouble() < 0.0; // false for NaN
if (isCell())
return asCell()->toBoolean(exec);
return isTrue(); // false, null, and undefined all convert to false.
}
ALWAYS_INLINE double JSValue::toNumber(ExecState* exec) const
{
if (isInt32())
return asInt32();
if (isDouble())
return asDouble();
if (isCell())
return asCell()->toNumber(exec);
if (isTrue())
return 1.0;
return isUndefined() ? nonInlineNaN() : 0; // null and false both convert to 0.
}
inline JSValue JSValue::getJSNumber()
{
if (isInt32() || isDouble())
return *this;
if (isCell())
return asCell()->getJSNumber();
return JSValue();
}
inline JSObject* JSValue::toObject(ExecState* exec) const
{
return isCell() ? asCell()->toObject(exec, exec->lexicalGlobalObject()) : toObjectSlowCase(exec, exec->lexicalGlobalObject());
}
inline JSObject* JSValue::toObject(ExecState* exec, JSGlobalObject* globalObject) const
{
return isCell() ? asCell()->toObject(exec, globalObject) : toObjectSlowCase(exec, globalObject);
}
inline JSObject* JSValue::toThisObject(ExecState* exec) const
{
return isCell() ? asCell()->toThisObject(exec) : toThisObjectSlowCase(exec);
}
inline Heap* Heap::heap(JSValue v)
{
if (!v.isCell())
return 0;
return heap(v.asCell());
}
inline Heap* Heap::heap(JSCell* c)
{
return MarkedSpace::heap(c);
}
#if ENABLE(JSC_ZOMBIES)
inline bool JSValue::isZombie() const
{
return isCell() && asCell() > (JSCell*)0x1ffffffffL && asCell()->isZombie();
}
#endif
inline void* MarkedBlock::allocate()
{
while (m_nextAtom < m_endAtom) {
if (!m_marks.testAndSet(m_nextAtom)) {
JSCell* cell = reinterpret_cast<JSCell*>(&atoms()[m_nextAtom]);
m_nextAtom += m_atomsPerCell;
cell->~JSCell();
return cell;
}
m_nextAtom += m_atomsPerCell;
}
return 0;
}
inline MarkedSpace::SizeClass& MarkedSpace::sizeClassFor(size_t bytes)
{
ASSERT(bytes && bytes < maxCellSize);
if (bytes < preciseCutoff)
return m_preciseSizeClasses[(bytes - 1) / preciseStep];
return m_impreciseSizeClasses[(bytes - 1) / impreciseStep];
}
inline void* MarkedSpace::allocate(size_t bytes)
{
SizeClass& sizeClass = sizeClassFor(bytes);
return allocateFromSizeClass(sizeClass);
}
inline void* Heap::allocate(size_t bytes)
{
ASSERT(globalData()->identifierTable == wtfThreadData().currentIdentifierTable());
ASSERT(JSLock::lockCount() > 0);
ASSERT(JSLock::currentThreadIsHoldingLock());
ASSERT(bytes <= MarkedSpace::maxCellSize);
ASSERT(m_operationInProgress == NoOperation);
m_operationInProgress = Allocation;
void* result = m_markedSpace.allocate(bytes);
m_operationInProgress = NoOperation;
if (result)
return result;
return allocateSlowCase(bytes);
}
inline void* JSCell::operator new(size_t size, JSGlobalData* globalData)
{
return globalData->heap.allocate(size);
}
inline void* JSCell::operator new(size_t size, ExecState* exec)
{
return exec->heap()->allocate(size);
}
} // namespace JSC
#endif // JSCell_h