1/*
2 * Copyright (C) 2008, 2009 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include "config.h"
27#include "Collector.h"
28
29#ifndef CollectorHeapIterator_h
30#define CollectorHeapIterator_h
31
32namespace JSC {
33
34 class CollectorHeapIterator {
35 public:
36 bool operator!=(const CollectorHeapIterator& other);
37 JSCell* operator*() const;
38
39 protected:
40 CollectorHeapIterator(CollectorHeap&, size_t startBlock, size_t startCell);
41 void advance(size_t cellsPerBlock);
42
43 CollectorHeap& m_heap;
44 size_t m_block;
45 size_t m_cell;
46 };
47
48 class LiveObjectIterator : public CollectorHeapIterator {
49 public:
50 LiveObjectIterator(CollectorHeap&, size_t startBlock, size_t startCell = 0);
51 LiveObjectIterator& operator++();
52 };
53
54 class DeadObjectIterator : public CollectorHeapIterator {
55 public:
56 DeadObjectIterator(CollectorHeap&, size_t startBlock, size_t startCell = 0);
57 DeadObjectIterator& operator++();
58 };
59
60 class ObjectIterator : public CollectorHeapIterator {
61 public:
62 ObjectIterator(CollectorHeap&, size_t startBlock, size_t startCell = 0);
63 ObjectIterator& operator++();
64 };
65
66 inline CollectorHeapIterator::CollectorHeapIterator(CollectorHeap& heap, size_t startBlock, size_t startCell)
67 : m_heap(heap)
68 , m_block(startBlock)
69 , m_cell(startCell)
70 {
71 }
72
73 inline bool CollectorHeapIterator::operator!=(const CollectorHeapIterator& other)
74 {
75 return m_block != other.m_block || m_cell != other.m_cell;
76 }
77
78 inline JSCell* CollectorHeapIterator::operator*() const
79 {
80 return reinterpret_cast<JSCell*>(m_heap.blocks[m_block]->cells + m_cell);
81 }
82
83 inline void CollectorHeapIterator::advance(size_t cellsPerBlock)
84 {
85 ++m_cell;
86 if (m_cell == cellsPerBlock) {
87 m_cell = 0;
88 ++m_block;
89 }
90 }
91
92 inline LiveObjectIterator::LiveObjectIterator(CollectorHeap& heap, size_t startBlock, size_t startCell)
93 : CollectorHeapIterator(heap, startBlock, startCell - 1)
94 {
95 ++(*this);
96 }
97
98 inline LiveObjectIterator& LiveObjectIterator::operator++()
99 {
100 advance(cellsPerBlock: HeapConstants::cellsPerBlock - 1);
101 if (m_block < m_heap.nextBlock || (m_block == m_heap.nextBlock && m_cell < m_heap.nextCell))
102 return *this;
103
104 while (m_block < m_heap.usedBlocks && !m_heap.blocks[m_block]->marked.get(n: m_cell))
105 advance(cellsPerBlock: HeapConstants::cellsPerBlock - 1);
106 return *this;
107 }
108
109 inline DeadObjectIterator::DeadObjectIterator(CollectorHeap& heap, size_t startBlock, size_t startCell)
110 : CollectorHeapIterator(heap, startBlock, startCell - 1)
111 {
112 ++(*this);
113 }
114
115 inline DeadObjectIterator& DeadObjectIterator::operator++()
116 {
117 do {
118 advance(cellsPerBlock: HeapConstants::cellsPerBlock);
119 ASSERT(m_block > m_heap.nextBlock || (m_block == m_heap.nextBlock && m_cell >= m_heap.nextCell));
120 } while (m_block < m_heap.usedBlocks && m_heap.blocks[m_block]->marked.get(n: m_cell));
121 return *this;
122 }
123
124 inline ObjectIterator::ObjectIterator(CollectorHeap& heap, size_t startBlock, size_t startCell)
125 : CollectorHeapIterator(heap, startBlock, startCell - 1)
126 {
127 ++(*this);
128 }
129
130 inline ObjectIterator& ObjectIterator::operator++()
131 {
132 advance(cellsPerBlock: HeapConstants::cellsPerBlock);
133 return *this;
134 }
135
136} // namespace JSC
137
138#endif // CollectorHeapIterator_h
139

source code of qtscript/src/3rdparty/javascriptcore/JavaScriptCore/runtime/CollectorHeapIterator.h