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
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
|
/*
* Copyright (C) 2008 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 COMPUTER, INC. ``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 COMPUTER, INC. OR
* 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.
*/
#ifndef Structure_h
#define Structure_h
#include "Identifier.h"
#include "JSType.h"
#include "JSValue.h"
#include "PropertyMapHashTable.h"
#include "StructureChain.h"
#include "StructureTransitionTable.h"
#include "TypeInfo.h"
#include "UString.h"
#include <wtf/PassRefPtr.h>
#include <wtf/RefCounted.h>
#ifndef NDEBUG
#define DUMP_PROPERTYMAP_STATS 0
#else
#define DUMP_PROPERTYMAP_STATS 0
#endif
namespace JSC {
class PropertyNameArray;
class PropertyNameArrayData;
class Structure : public RefCounted<Structure> {
public:
friend class JIT;
static PassRefPtr<Structure> create(JSValue prototype, const TypeInfo& typeInfo)
{
return adoptRef(new Structure(prototype, typeInfo));
}
static void startIgnoringLeaks();
static void stopIgnoringLeaks();
static void dumpStatistics();
static PassRefPtr<Structure> addPropertyTransition(Structure*, const Identifier& propertyName, unsigned attributes, JSCell* specificValue, size_t& offset);
static PassRefPtr<Structure> addPropertyTransitionToExistingStructure(Structure*, const Identifier& propertyName, unsigned attributes, JSCell* specificValue, size_t& offset);
static PassRefPtr<Structure> removePropertyTransition(Structure*, const Identifier& propertyName, size_t& offset);
static PassRefPtr<Structure> changePrototypeTransition(Structure*, JSValue prototype);
static PassRefPtr<Structure> despecifyFunctionTransition(Structure*, const Identifier&);
static PassRefPtr<Structure> getterSetterTransition(Structure*);
static PassRefPtr<Structure> toDictionaryTransition(Structure*);
static PassRefPtr<Structure> fromDictionaryTransition(Structure*);
~Structure();
void mark()
{
if (!m_prototype.marked())
m_prototype.mark();
}
// These should be used with caution.
size_t addPropertyWithoutTransition(const Identifier& propertyName, unsigned attributes, JSCell* specificValue);
size_t removePropertyWithoutTransition(const Identifier& propertyName);
void setPrototypeWithoutTransition(JSValue prototype) { m_prototype = prototype; }
bool isDictionary() const { return m_isDictionary; }
const TypeInfo& typeInfo() const { return m_typeInfo; }
JSValue storedPrototype() const { return m_prototype; }
JSValue prototypeForLookup(ExecState*) const;
StructureChain* prototypeChain(ExecState*) const;
Structure* previousID() const { return m_previous.get(); }
void growPropertyStorageCapacity();
size_t propertyStorageCapacity() const { return m_propertyStorageCapacity; }
size_t propertyStorageSize() const { return m_propertyTable ? m_propertyTable->keyCount + (m_propertyTable->deletedOffsets ? m_propertyTable->deletedOffsets->size() : 0) : m_offset + 1; }
bool isUsingInlineStorage() const;
size_t get(const Identifier& propertyName);
size_t get(const UString::Rep* rep, unsigned& attributes, JSCell*& specificValue);
size_t get(const Identifier& propertyName, unsigned& attributes, JSCell*& specificValue)
{
ASSERT(!propertyName.isNull());
return get(propertyName._ustring.rep(), attributes, specificValue);
}
void getEnumerablePropertyNames(ExecState*, PropertyNameArray&, JSObject*);
bool hasGetterSetterProperties() const { return m_hasGetterSetterProperties; }
void setHasGetterSetterProperties(bool hasGetterSetterProperties) { m_hasGetterSetterProperties = hasGetterSetterProperties; }
bool isEmpty() const { return m_propertyTable ? !m_propertyTable->keyCount : m_offset == noOffset; }
JSCell* specificValue() { return m_specificValueInPrevious; }
void despecifyDictionaryFunction(const Identifier& propertyName);
private:
Structure(JSValue prototype, const TypeInfo&);
size_t put(const Identifier& propertyName, unsigned attributes, JSCell* specificValue);
size_t remove(const Identifier& propertyName);
void getEnumerableNamesFromPropertyTable(PropertyNameArray&);
void getEnumerableNamesFromClassInfoTable(ExecState*, const ClassInfo*, PropertyNameArray&);
void expandPropertyMapHashTable();
void rehashPropertyMapHashTable();
void rehashPropertyMapHashTable(unsigned newTableSize);
void createPropertyMapHashTable();
void createPropertyMapHashTable(unsigned newTableSize);
void insertIntoPropertyMapHashTable(const PropertyMapEntry&);
void checkConsistency();
bool despecifyFunction(const Identifier&);
PropertyMapHashTable* copyPropertyTable();
void materializePropertyMap();
void materializePropertyMapIfNecessary()
{
if (m_propertyTable || !m_previous)
return;
materializePropertyMap();
}
void clearEnumerationCache();
signed char transitionCount() const
{
// Since the number of transitions is always the same as m_offset, we keep the size of Structure down by not storing both.
return m_offset == noOffset ? 0 : m_offset + 1;
}
bool isValid(ExecState*, StructureChain* cachedPrototypeChain) const;
static const unsigned emptyEntryIndex = 0;
static const signed char s_maxTransitionLength = 64;
static const signed char noOffset = -1;
TypeInfo m_typeInfo;
JSValue m_prototype;
mutable RefPtr<StructureChain> m_cachedPrototypeChain;
RefPtr<Structure> m_previous;
RefPtr<UString::Rep> m_nameInPrevious;
union {
Structure* singleTransition;
StructureTransitionTable* table;
} m_transitions;
JSCell* m_specificValueInPrevious;
RefPtr<PropertyNameArrayData> m_cachedPropertyNameArrayData;
PropertyMapHashTable* m_propertyTable;
size_t m_propertyStorageCapacity;
signed char m_offset;
bool m_isDictionary : 1;
bool m_isPinnedPropertyTable : 1;
bool m_hasGetterSetterProperties : 1;
bool m_usingSingleTransitionSlot : 1;
unsigned m_attributesInPrevious : 7;
};
inline size_t Structure::get(const Identifier& propertyName)
{
ASSERT(!propertyName.isNull());
materializePropertyMapIfNecessary();
if (!m_propertyTable)
return WTF::notFound;
UString::Rep* rep = propertyName._ustring.rep();
unsigned i = rep->computedHash();
#if DUMP_PROPERTYMAP_STATS
++numProbes;
#endif
unsigned entryIndex = m_propertyTable->entryIndices[i & m_propertyTable->sizeMask];
if (entryIndex == emptyEntryIndex)
return WTF::notFound;
if (rep == m_propertyTable->entries()[entryIndex - 1].key)
return m_propertyTable->entries()[entryIndex - 1].offset;
#if DUMP_PROPERTYMAP_STATS
++numCollisions;
#endif
unsigned k = 1 | WTF::doubleHash(rep->computedHash());
while (1) {
i += k;
#if DUMP_PROPERTYMAP_STATS
++numRehashes;
#endif
entryIndex = m_propertyTable->entryIndices[i & m_propertyTable->sizeMask];
if (entryIndex == emptyEntryIndex)
return WTF::notFound;
if (rep == m_propertyTable->entries()[entryIndex - 1].key)
return m_propertyTable->entries()[entryIndex - 1].offset;
}
}
} // namespace JSC
#endif // Structure_h
|
