1/*
2 * Copyright (C) 2013 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. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef DeferGC_h
27#define DeferGC_h
28
29#include "Heap.h"
30#include <wtf/Noncopyable.h>
31#include <wtf/ThreadSpecific.h>
32
33namespace JSC {
34
35class DeferGC {
36 WTF_MAKE_NONCOPYABLE(DeferGC);
37public:
38 DeferGC(Heap& heap)
39 : m_heap(heap)
40 {
41 m_heap.incrementDeferralDepth();
42 }
43
44 ~DeferGC()
45 {
46 m_heap.decrementDeferralDepthAndGCIfNeeded();
47 }
48
49private:
50 Heap& m_heap;
51};
52
53class DeferGCForAWhile {
54 WTF_MAKE_NONCOPYABLE(DeferGCForAWhile);
55public:
56 DeferGCForAWhile(Heap& heap)
57 : m_heap(heap)
58 {
59 m_heap.incrementDeferralDepth();
60 }
61
62 ~DeferGCForAWhile()
63 {
64 m_heap.decrementDeferralDepth();
65 }
66
67private:
68 Heap& m_heap;
69};
70
71#ifndef NDEBUG
72class DisallowGC {
73 WTF_MAKE_NONCOPYABLE(DisallowGC);
74public:
75 DisallowGC()
76 {
77 WTF::threadSpecificSet(s_isGCDisallowedOnCurrentThread, reinterpret_cast<void*>(true));
78 }
79
80 ~DisallowGC()
81 {
82 WTF::threadSpecificSet(s_isGCDisallowedOnCurrentThread, reinterpret_cast<void*>(false));
83 }
84
85 static bool isGCDisallowedOnCurrentThread()
86 {
87 return !!WTF::threadSpecificGet(s_isGCDisallowedOnCurrentThread);
88 }
89 static void initialize()
90 {
91 WTF::threadSpecificKeyCreate(&s_isGCDisallowedOnCurrentThread, 0);
92 }
93
94 JS_EXPORT_PRIVATE static WTF::ThreadSpecificKey s_isGCDisallowedOnCurrentThread;
95};
96#endif // NDEBUG
97
98} // namespace JSC
99
100#endif // DeferGC_h
101
102