1/*
2 * Copyright (C) 2013-2016 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. AND ITS CONTRIBUTORS ``AS IS''
14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
23 * THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include "config.h"
27#include "DFGDesiredWeakReferences.h"
28
29#if ENABLE(DFG_JIT)
30
31#include "CodeBlock.h"
32#include "DFGCommonData.h"
33#include "JSCInlines.h"
34
35namespace JSC { namespace DFG {
36
37DesiredWeakReferences::DesiredWeakReferences()
38 : m_codeBlock(nullptr)
39{
40}
41
42DesiredWeakReferences::DesiredWeakReferences(CodeBlock* codeBlock)
43 : m_codeBlock(codeBlock)
44{
45}
46
47DesiredWeakReferences::~DesiredWeakReferences()
48{
49}
50
51void DesiredWeakReferences::addLazily(JSCell* cell)
52{
53 if (cell)
54 m_references.add(cell);
55}
56
57void DesiredWeakReferences::addLazily(JSValue value)
58{
59 if (value.isCell())
60 addLazily(value.asCell());
61}
62
63bool DesiredWeakReferences::contains(JSCell* cell)
64{
65 return m_references.contains(cell);
66}
67
68void DesiredWeakReferences::reallyAdd(VM& vm, CommonData* common)
69{
70 for (JSCell* target : m_references) {
71 if (Structure* structure = jsDynamicCast<Structure*>(vm, target)) {
72 common->weakStructureReferences.append(
73 WriteBarrier<Structure>(vm, m_codeBlock, structure));
74 } else {
75 // There are weird relationships in how optimized CodeBlocks
76 // point to other CodeBlocks. We don't want to have them be
77 // part of the weak pointer set. For example, an optimized CodeBlock
78 // having a weak pointer to itself will cause it to get collected.
79 RELEASE_ASSERT(!jsDynamicCast<CodeBlock*>(vm, target));
80
81 common->weakReferences.append(
82 WriteBarrier<JSCell>(vm, m_codeBlock, target));
83 }
84 }
85}
86
87void DesiredWeakReferences::visitChildren(SlotVisitor& visitor)
88{
89 for (JSCell* target : m_references)
90 visitor.appendUnbarriered(target);
91}
92
93} } // namespace JSC::DFG
94
95#endif // ENABLE(DFG_JIT)
96