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