1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
|
/*
* 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, 2011 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;
typedef MarkStack SlotVisitor;
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();
size_t highWaterMark();
void setHighWaterMark(size_t);
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 JSGlobalData* MarkedSpace::globalData()
{
return m_globalData;
}
inline size_t MarkedSpace::highWaterMark()
{
return m_highWaterMark;
}
inline void MarkedSpace::setHighWaterMark(size_t highWaterMark)
{
m_highWaterMark = highWaterMark;
}
inline MarkedSpace::SizeClass::SizeClass()
: nextBlock(0)
, cellSize(0)
{
}
inline void MarkedSpace::SizeClass::reset()
{
nextBlock = blockList.head();
}
} // namespace JSC
#endif // MarkedSpace_h
|
