1/*
2 * Copyright (C) 2012, 2014, 2015 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 *
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of Apple Inc. ("Apple") nor the names of
14 * its contributors may be used to endorse or promote products derived
15 * from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#include "config.h"
30#include "SymbolTable.h"
31
32#include "CodeBlock.h"
33#include "JSDestructibleObject.h"
34#include "JSCInlines.h"
35#include "SlotVisitorInlines.h"
36#include "TypeProfiler.h"
37
38namespace JSC {
39
40const ClassInfo SymbolTable::s_info = { "SymbolTable", nullptr, nullptr, nullptr, CREATE_METHOD_TABLE(SymbolTable) };
41
42SymbolTableEntry& SymbolTableEntry::copySlow(const SymbolTableEntry& other)
43{
44 ASSERT(other.isFat());
45 FatEntry* newFatEntry = new FatEntry(*other.fatEntry());
46 freeFatEntry();
47 m_bits = bitwise_cast<intptr_t>(newFatEntry);
48 return *this;
49}
50
51void SymbolTable::destroy(JSCell* cell)
52{
53 SymbolTable* thisObject = static_cast<SymbolTable*>(cell);
54 thisObject->SymbolTable::~SymbolTable();
55}
56
57void SymbolTableEntry::freeFatEntrySlow()
58{
59 ASSERT(isFat());
60 delete fatEntry();
61}
62
63void SymbolTableEntry::prepareToWatch()
64{
65 if (!isWatchable())
66 return;
67 FatEntry* entry = inflate();
68 if (entry->m_watchpoints)
69 return;
70 entry->m_watchpoints = adoptRef(new WatchpointSet(ClearWatchpoint));
71}
72
73SymbolTableEntry::FatEntry* SymbolTableEntry::inflateSlow()
74{
75 FatEntry* entry = new FatEntry(m_bits);
76 m_bits = bitwise_cast<intptr_t>(entry);
77 return entry;
78}
79
80SymbolTable::SymbolTable(VM& vm)
81 : JSCell(vm, vm.symbolTableStructure.get())
82 , m_usesNonStrictEval(false)
83 , m_nestedLexicalScope(false)
84 , m_scopeType(VarScope)
85{
86}
87
88SymbolTable::~SymbolTable() { }
89
90void SymbolTable::finishCreation(VM& vm)
91{
92 Base::finishCreation(vm);
93}
94
95void SymbolTable::visitChildren(JSCell* thisCell, SlotVisitor& visitor)
96{
97 SymbolTable* thisSymbolTable = jsCast<SymbolTable*>(thisCell);
98 Base::visitChildren(thisSymbolTable, visitor);
99
100 visitor.append(thisSymbolTable->m_arguments);
101
102 if (thisSymbolTable->m_rareData)
103 visitor.append(thisSymbolTable->m_rareData->m_codeBlock);
104
105 // Save some memory. This is O(n) to rebuild and we do so on the fly.
106 ConcurrentJSLocker locker(thisSymbolTable->m_lock);
107 thisSymbolTable->m_localToEntry = nullptr;
108}
109
110const SymbolTable::LocalToEntryVec& SymbolTable::localToEntry(const ConcurrentJSLocker&)
111{
112 if (UNLIKELY(!m_localToEntry)) {
113 unsigned size = 0;
114 for (auto& entry : m_map) {
115 VarOffset offset = entry.value.varOffset();
116 if (offset.isScope())
117 size = std::max(size, offset.scopeOffset().offset() + 1);
118 }
119
120 m_localToEntry = std::make_unique<LocalToEntryVec>(size, nullptr);
121 for (auto& entry : m_map) {
122 VarOffset offset = entry.value.varOffset();
123 if (offset.isScope())
124 m_localToEntry->at(offset.scopeOffset().offset()) = &entry.value;
125 }
126 }
127
128 return *m_localToEntry;
129}
130
131SymbolTableEntry* SymbolTable::entryFor(const ConcurrentJSLocker& locker, ScopeOffset offset)
132{
133 auto& toEntryVector = localToEntry(locker);
134 if (offset.offset() >= toEntryVector.size())
135 return nullptr;
136 return toEntryVector[offset.offset()];
137}
138
139SymbolTable* SymbolTable::cloneScopePart(VM& vm)
140{
141 SymbolTable* result = SymbolTable::create(vm);
142
143 result->m_usesNonStrictEval = m_usesNonStrictEval;
144 result->m_nestedLexicalScope = m_nestedLexicalScope;
145 result->m_scopeType = m_scopeType;
146
147 for (auto iter = m_map.begin(), end = m_map.end(); iter != end; ++iter) {
148 if (!iter->value.varOffset().isScope())
149 continue;
150 result->m_map.add(
151 iter->key,
152 SymbolTableEntry(iter->value.varOffset(), iter->value.getAttributes()));
153 }
154
155 result->m_maxScopeOffset = m_maxScopeOffset;
156
157 if (ScopedArgumentsTable* arguments = this->arguments())
158 result->m_arguments.set(vm, result, arguments);
159
160 if (m_rareData) {
161 result->m_rareData = std::make_unique<SymbolTableRareData>();
162
163 {
164 auto iter = m_rareData->m_uniqueIDMap.begin();
165 auto end = m_rareData->m_uniqueIDMap.end();
166 for (; iter != end; ++iter)
167 result->m_rareData->m_uniqueIDMap.set(iter->key, iter->value);
168 }
169
170 {
171 auto iter = m_rareData->m_offsetToVariableMap.begin();
172 auto end = m_rareData->m_offsetToVariableMap.end();
173 for (; iter != end; ++iter)
174 result->m_rareData->m_offsetToVariableMap.set(iter->key, iter->value);
175 }
176
177 {
178 auto iter = m_rareData->m_uniqueTypeSetMap.begin();
179 auto end = m_rareData->m_uniqueTypeSetMap.end();
180 for (; iter != end; ++iter)
181 result->m_rareData->m_uniqueTypeSetMap.set(iter->key, iter->value);
182 }
183 }
184
185 return result;
186}
187
188void SymbolTable::prepareForTypeProfiling(const ConcurrentJSLocker&)
189{
190 if (m_rareData)
191 return;
192
193 m_rareData = std::make_unique<SymbolTableRareData>();
194
195 for (auto iter = m_map.begin(), end = m_map.end(); iter != end; ++iter) {
196 m_rareData->m_uniqueIDMap.set(iter->key, TypeProfilerNeedsUniqueIDGeneration);
197 m_rareData->m_offsetToVariableMap.set(iter->value.varOffset(), iter->key);
198 }
199}
200
201CodeBlock* SymbolTable::rareDataCodeBlock()
202{
203 if (!m_rareData)
204 return nullptr;
205
206 return m_rareData->m_codeBlock.get();
207}
208
209void SymbolTable::setRareDataCodeBlock(CodeBlock* codeBlock)
210{
211 if (!m_rareData)
212 m_rareData = std::make_unique<SymbolTableRareData>();
213
214 ASSERT(!m_rareData->m_codeBlock);
215 m_rareData->m_codeBlock.set(*codeBlock->vm(), this, codeBlock);
216}
217
218GlobalVariableID SymbolTable::uniqueIDForVariable(const ConcurrentJSLocker&, UniquedStringImpl* key, VM& vm)
219{
220 RELEASE_ASSERT(m_rareData);
221
222 auto iter = m_rareData->m_uniqueIDMap.find(key);
223 auto end = m_rareData->m_uniqueIDMap.end();
224 if (iter == end)
225 return TypeProfilerNoGlobalIDExists;
226
227 GlobalVariableID id = iter->value;
228 if (id == TypeProfilerNeedsUniqueIDGeneration) {
229 id = vm.typeProfiler()->getNextUniqueVariableID();
230 m_rareData->m_uniqueIDMap.set(key, id);
231 m_rareData->m_uniqueTypeSetMap.set(key, TypeSet::create()); // Make a new global typeset for this corresponding ID.
232 }
233
234 return id;
235}
236
237GlobalVariableID SymbolTable::uniqueIDForOffset(const ConcurrentJSLocker& locker, VarOffset offset, VM& vm)
238{
239 RELEASE_ASSERT(m_rareData);
240
241 auto iter = m_rareData->m_offsetToVariableMap.find(offset);
242 auto end = m_rareData->m_offsetToVariableMap.end();
243 if (iter == end)
244 return TypeProfilerNoGlobalIDExists;
245
246 return uniqueIDForVariable(locker, iter->value.get(), vm);
247}
248
249RefPtr<TypeSet> SymbolTable::globalTypeSetForOffset(const ConcurrentJSLocker& locker, VarOffset offset, VM& vm)
250{
251 RELEASE_ASSERT(m_rareData);
252
253 uniqueIDForOffset(locker, offset, vm); // Lazily create the TypeSet if necessary.
254
255 auto iter = m_rareData->m_offsetToVariableMap.find(offset);
256 auto end = m_rareData->m_offsetToVariableMap.end();
257 if (iter == end)
258 return nullptr;
259
260 return globalTypeSetForVariable(locker, iter->value.get(), vm);
261}
262
263RefPtr<TypeSet> SymbolTable::globalTypeSetForVariable(const ConcurrentJSLocker& locker, UniquedStringImpl* key, VM& vm)
264{
265 RELEASE_ASSERT(m_rareData);
266
267 uniqueIDForVariable(locker, key, vm); // Lazily create the TypeSet if necessary.
268
269 auto iter = m_rareData->m_uniqueTypeSetMap.find(key);
270 auto end = m_rareData->m_uniqueTypeSetMap.end();
271 if (iter == end)
272 return nullptr;
273
274 return iter->value;
275}
276
277} // namespace JSC
278
279