forked from phoboslab/JavaScriptCore-iOS
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathMarkedSpace.h
More file actions
190 lines (152 loc) · 5.76 KB
/
MarkedSpace.h
File metadata and controls
190 lines (152 loc) · 5.76 KB
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
189
190
/*
* Copyright (C) 1999-2000 Harri Porten ([email protected])
* Copyright (C) 2001 Peter Kelly ([email protected])
* 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 "MarkedAllocator.h"
#include "MarkedBlock.h"
#include "MarkedBlockSet.h"
#include <wtf/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 LiveObjectIterator;
class LLIntOffsetsExtractor;
class WeakGCHandle;
class SlotVisitor;
class MarkedSpace {
WTF_MAKE_NONCOPYABLE(MarkedSpace);
public:
static const size_t maxCellSize = 2048;
MarkedSpace(Heap*);
MarkedAllocator& firstAllocator();
MarkedAllocator& allocatorFor(size_t);
MarkedAllocator& allocatorFor(MarkedBlock*);
MarkedAllocator& destructorAllocatorFor(size_t);
void* allocateWithDestructor(size_t);
void* allocateWithoutDestructor(size_t);
void resetAllocators();
MarkedBlockSet& blocks() { return m_blocks; }
void canonicalizeCellLivenessData();
typedef HashSet<MarkedBlock*>::iterator BlockIterator;
template<typename Functor> typename Functor::ReturnType forEachCell(Functor&);
template<typename Functor> typename Functor::ReturnType forEachCell();
template<typename Functor> typename Functor::ReturnType forEachBlock(Functor&);
template<typename Functor> typename Functor::ReturnType forEachBlock();
void shrink();
void freeBlocks(MarkedBlock* head);
void didAddBlock(MarkedBlock*);
void didConsumeFreeList(MarkedBlock*);
bool isPagedOut(double deadline);
private:
friend class LLIntOffsetsExtractor;
// [ 32... 256 ]
static const size_t preciseStep = MarkedBlock::atomSize;
static const size_t preciseCutoff = 256;
static const size_t preciseCount = preciseCutoff / preciseStep;
// [ 512... 2048 ]
static const size_t impreciseStep = preciseCutoff;
static const size_t impreciseCutoff = maxCellSize;
static const size_t impreciseCount = impreciseCutoff / impreciseStep;
struct Subspace {
FixedArray<MarkedAllocator, preciseCount> preciseAllocators;
FixedArray<MarkedAllocator, impreciseCount> impreciseAllocators;
};
Subspace m_destructorSpace;
Subspace m_normalSpace;
Heap* m_heap;
MarkedBlockSet m_blocks;
};
template<typename Functor> inline typename Functor::ReturnType MarkedSpace::forEachCell(Functor& functor)
{
canonicalizeCellLivenessData();
BlockIterator end = m_blocks.set().end();
for (BlockIterator it = m_blocks.set().begin(); it != end; ++it)
(*it)->forEachCell(functor);
return functor.returnValue();
}
template<typename Functor> inline typename Functor::ReturnType MarkedSpace::forEachCell()
{
Functor functor;
return forEachCell(functor);
}
inline MarkedAllocator& MarkedSpace::firstAllocator()
{
return m_normalSpace.preciseAllocators[0];
}
inline MarkedAllocator& MarkedSpace::allocatorFor(size_t bytes)
{
ASSERT(bytes && bytes <= maxCellSize);
if (bytes <= preciseCutoff)
return m_normalSpace.preciseAllocators[(bytes - 1) / preciseStep];
return m_normalSpace.impreciseAllocators[(bytes - 1) / impreciseStep];
}
inline MarkedAllocator& MarkedSpace::allocatorFor(MarkedBlock* block)
{
if (block->cellsNeedDestruction())
return destructorAllocatorFor(block->cellSize());
return allocatorFor(block->cellSize());
}
inline MarkedAllocator& MarkedSpace::destructorAllocatorFor(size_t bytes)
{
ASSERT(bytes && bytes <= maxCellSize);
if (bytes <= preciseCutoff)
return m_destructorSpace.preciseAllocators[(bytes - 1) / preciseStep];
return m_destructorSpace.impreciseAllocators[(bytes - 1) / impreciseStep];
}
inline void* MarkedSpace::allocateWithoutDestructor(size_t bytes)
{
return allocatorFor(bytes).allocate();
}
inline void* MarkedSpace::allocateWithDestructor(size_t bytes)
{
return destructorAllocatorFor(bytes).allocate();
}
template <typename Functor> inline typename Functor::ReturnType MarkedSpace::forEachBlock(Functor& functor)
{
for (size_t i = 0; i < preciseCount; ++i) {
m_normalSpace.preciseAllocators[i].forEachBlock(functor);
m_destructorSpace.preciseAllocators[i].forEachBlock(functor);
}
for (size_t i = 0; i < impreciseCount; ++i) {
m_normalSpace.impreciseAllocators[i].forEachBlock(functor);
m_destructorSpace.impreciseAllocators[i].forEachBlock(functor);
}
return functor.returnValue();
}
template <typename Functor> inline typename Functor::ReturnType MarkedSpace::forEachBlock()
{
Functor functor;
return forEachBlock(functor);
}
inline void MarkedSpace::didAddBlock(MarkedBlock* block)
{
m_blocks.add(block);
}
} // namespace JSC
#endif // MarkedSpace_h