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
|
/*
* Copyright (C) 2013 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include "UnusedPointer.h"
#include <wtf/Vector.h>
namespace JSC {
class Structure;
#if USE(JSVALUE64)
typedef uint32_t StructureID;
inline StructureID nukedStructureIDBit()
{
return 0x80000000u;
}
inline StructureID nuke(StructureID id)
{
return id | nukedStructureIDBit();
}
inline bool isNuked(StructureID id)
{
return !!(id & nukedStructureIDBit());
}
inline StructureID decontaminate(StructureID id)
{
return id & ~nukedStructureIDBit();
}
#else
typedef Structure* StructureID;
inline StructureID nukedStructureIDBit()
{
return bitwise_cast<StructureID>(static_cast<uintptr_t>(1));
}
inline StructureID nuke(StructureID id)
{
return bitwise_cast<StructureID>(bitwise_cast<uintptr_t>(id) | bitwise_cast<uintptr_t>(nukedStructureIDBit()));
}
inline bool isNuked(StructureID id)
{
return !!(bitwise_cast<uintptr_t>(id) & bitwise_cast<uintptr_t>(nukedStructureIDBit()));
}
inline StructureID decontaminate(StructureID id)
{
return bitwise_cast<StructureID>(bitwise_cast<uintptr_t>(id) & ~bitwise_cast<uintptr_t>(nukedStructureIDBit()));
}
#endif
class StructureIDTable {
friend class LLIntOffsetsExtractor;
public:
StructureIDTable();
void** base() { return reinterpret_cast<void**>(&m_table); }
Structure* get(StructureID);
void deallocateID(Structure*, StructureID);
StructureID allocateID(Structure*);
void flushOldTables();
size_t size() const { return m_size; }
private:
void resize(size_t newCapacity);
union StructureOrOffset {
WTF_MAKE_FAST_ALLOCATED;
public:
Structure* structure;
StructureID offset;
};
StructureOrOffset* table() const { return m_table.get(); }
static const size_t s_initialSize = 256;
Vector<std::unique_ptr<StructureOrOffset[]>> m_oldTables;
uint32_t m_firstFreeOffset;
std::unique_ptr<StructureOrOffset[]> m_table;
size_t m_size;
size_t m_capacity;
#if USE(JSVALUE64)
static const StructureID s_unusedID = unusedPointer;
#endif
};
inline Structure* StructureIDTable::get(StructureID structureID)
{
#if USE(JSVALUE64)
ASSERT_WITH_SECURITY_IMPLICATION(structureID);
ASSERT_WITH_SECURITY_IMPLICATION(!isNuked(structureID));
ASSERT_WITH_SECURITY_IMPLICATION(structureID < m_capacity);
return table()[structureID].structure;
#else
return structureID;
#endif
}
} // namespace JSC
|
