1/*
2 * Copyright (C) 2012-2017 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 "JSSegmentedVariableObject.h"
31
32#include "HeapSnapshotBuilder.h"
33#include "JSCInlines.h"
34
35namespace JSC {
36
37const ClassInfo JSSegmentedVariableObject::s_info = { "SegmentedVariableObject", &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(JSSegmentedVariableObject) };
38
39ScopeOffset JSSegmentedVariableObject::findVariableIndex(void* variableAddress)
40{
41 auto locker = holdLock(cellLock());
42
43 for (unsigned i = m_variables.size(); i--;) {
44 if (&m_variables[i] != variableAddress)
45 continue;
46 return ScopeOffset(i);
47 }
48 CRASH();
49 return ScopeOffset();
50}
51
52ScopeOffset JSSegmentedVariableObject::addVariables(unsigned numberOfVariablesToAdd, JSValue initialValue)
53{
54 auto locker = holdLock(cellLock());
55
56 size_t oldSize = m_variables.size();
57 m_variables.grow(oldSize + numberOfVariablesToAdd);
58
59 for (size_t i = numberOfVariablesToAdd; i--;)
60 m_variables[oldSize + i].setWithoutWriteBarrier(initialValue);
61
62 return ScopeOffset(oldSize);
63}
64
65void JSSegmentedVariableObject::visitChildren(JSCell* cell, SlotVisitor& slotVisitor)
66{
67 JSSegmentedVariableObject* thisObject = jsCast<JSSegmentedVariableObject*>(cell);
68 ASSERT_GC_OBJECT_INHERITS(thisObject, info());
69 Base::visitChildren(thisObject, slotVisitor);
70
71 // FIXME: We could avoid locking here if SegmentedVector was lock-free. It could be made lock-free
72 // relatively easily.
73 auto locker = holdLock(thisObject->cellLock());
74 for (unsigned i = thisObject->m_variables.size(); i--;)
75 slotVisitor.appendHidden(thisObject->m_variables[i]);
76}
77
78void JSSegmentedVariableObject::heapSnapshot(JSCell* cell, HeapSnapshotBuilder& builder)
79{
80 JSSegmentedVariableObject* thisObject = jsCast<JSSegmentedVariableObject*>(cell);
81 Base::heapSnapshot(cell, builder);
82
83 ConcurrentJSLocker locker(thisObject->symbolTable()->m_lock);
84 SymbolTable::Map::iterator end = thisObject->symbolTable()->end(locker);
85 for (SymbolTable::Map::iterator it = thisObject->symbolTable()->begin(locker); it != end; ++it) {
86 SymbolTableEntry::Fast entry = it->value;
87 ASSERT(!entry.isNull());
88 ScopeOffset offset = entry.scopeOffset();
89 if (!thisObject->isValidScopeOffset(offset))
90 continue;
91
92 JSValue toValue = thisObject->variableAt(offset).get();
93 if (toValue && toValue.isCell())
94 builder.appendVariableNameEdge(thisObject, toValue.asCell(), it->key.get());
95 }
96}
97
98void JSSegmentedVariableObject::destroy(JSCell* cell)
99{
100 static_cast<JSSegmentedVariableObject*>(cell)->JSSegmentedVariableObject::~JSSegmentedVariableObject();
101}
102
103JSSegmentedVariableObject::JSSegmentedVariableObject(VM& vm, Structure* structure, JSScope* scope)
104 : JSSymbolTableObject(vm, structure, scope)
105 , m_classInfo(structure->classInfo())
106{
107}
108
109JSSegmentedVariableObject::~JSSegmentedVariableObject()
110{
111#ifndef NDEBUG
112 ASSERT(!m_alreadyDestroyed);
113 m_alreadyDestroyed = true;
114#endif
115}
116
117void JSSegmentedVariableObject::finishCreation(VM& vm)
118{
119 Base::finishCreation(vm);
120 setSymbolTable(vm, SymbolTable::create(vm));
121 vm.heap.addFinalizer(this, [] (JSCell* cell) {
122 static_cast<JSSegmentedVariableObject*>(cell)->classInfo()->methodTable.destroy(cell);
123 });
124}
125
126} // namespace JSC
127
128