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/*
* Copyright (C) 1999-2000 Harri Porten (porten@kde.org)
* Copyright (C) 2001 Peter Kelly (pmk@post.com)
* Copyright (C) 2003, 2004, 2005, 2006, 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 Lesser 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#ifndef MarkedSpace_h
#define MarkedSpace_h
#include "MachineStackMarker.h"
#include "MarkedBlock.h"
#include "PageAllocationAligned.h"
#include <wtf/Bitmap.h>
#include <wtf/DoublyLinkedList.h>
#include <wtf/FixedArray.h>
#include <wtf/HashSet.h>
#include <wtf/Noncopyable.h>
#include <wtf/Vector.h>
#define ASSERT_CLASS_FITS_IN_CELL(class) COMPILE_ASSERT(sizeof(class) < MarkedSpace::maxCellSize, class_fits_in_cell)
namespace JSC {
class Heap;
class JSCell;
class JSGlobalData;
class LiveObjectIterator;
class MarkStack;
class WeakGCHandle;
class MarkedSpace {
WTF_MAKE_NONCOPYABLE(MarkedSpace);
public:
// Currently public for use in assertions.
static const size_t maxCellSize = 1024;
static Heap* heap(JSCell*);
static bool isMarked(const JSCell*);
static bool testAndSetMarked(const JSCell*);
static void setMarked(const JSCell*);
MarkedSpace(JSGlobalData*);
void destroy();
JSGlobalData* globalData() { return m_globalData; }
size_t highWaterMark() { return m_highWaterMark; }
void setHighWaterMark(size_t highWaterMark) { m_highWaterMark = highWaterMark; }
void* allocate(size_t);
void clearMarks();
void markRoots();
void reset();
void sweep();
void shrink();
size_t size() const;
size_t capacity() const;
size_t objectCount() const;
bool contains(const void*);
template<typename Functor> void forEach(Functor&);
private:
// [ 8, 16... 128 )
static const size_t preciseStep = MarkedBlock::atomSize;
static const size_t preciseCutoff = 128;
static const size_t preciseCount = preciseCutoff / preciseStep - 1;
// [ 128, 256... 1024 )
static const size_t impreciseStep = preciseCutoff;
static const size_t impreciseCutoff = maxCellSize;
static const size_t impreciseCount = impreciseCutoff / impreciseStep - 1;
typedef HashSet<MarkedBlock*>::iterator BlockIterator;
struct SizeClass {
SizeClass();
void reset();
MarkedBlock* nextBlock;
DoublyLinkedList<MarkedBlock> blockList;
size_t cellSize;
};
MarkedBlock* allocateBlock(SizeClass&);
void freeBlocks(DoublyLinkedList<MarkedBlock>&);
SizeClass& sizeClassFor(size_t);
void* allocateFromSizeClass(SizeClass&);
void clearMarks(MarkedBlock*);
SizeClass m_preciseSizeClasses[preciseCount];
SizeClass m_impreciseSizeClasses[impreciseCount];
HashSet<MarkedBlock*> m_blocks;
size_t m_waterMark;
size_t m_highWaterMark;
JSGlobalData* m_globalData;
};
inline Heap* MarkedSpace::heap(JSCell* cell)
{
return MarkedBlock::blockFor(cell)->heap();
}
inline bool MarkedSpace::isMarked(const JSCell* cell)
{
return MarkedBlock::blockFor(cell)->isMarked(cell);
}
inline bool MarkedSpace::testAndSetMarked(const JSCell* cell)
{
return MarkedBlock::blockFor(cell)->testAndSetMarked(cell);
}
inline void MarkedSpace::setMarked(const JSCell* cell)
{
MarkedBlock::blockFor(cell)->setMarked(cell);
}
inline bool MarkedSpace::contains(const void* x)
{
if (!MarkedBlock::isAtomAligned(x))
return false;
MarkedBlock* block = MarkedBlock::blockFor(x);
if (!block || !m_blocks.contains(block))
return false;
return block->contains(x);
}
template <typename Functor> inline void MarkedSpace::forEach(Functor& functor)
{
BlockIterator end = m_blocks.end();
for (BlockIterator it = m_blocks.begin(); it != end; ++it)
(*it)->forEach(functor);
}
inline MarkedSpace::SizeClass::SizeClass()
: nextBlock(0)
, cellSize(0)
{
}
inline void MarkedSpace::SizeClass::reset()
{
nextBlock = blockList.head();
}
} // namespace JSC
#endif // MarkedSpace_h
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