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/*
* Copyright (C) 2017 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include "MutatorScheduler.h"
namespace JSC {
// The JSC concurrent GC relies on stopping the world to stay ahead of the retreating wavefront.
// It so happens that the same API can be reused to implement a non-concurrent GC mode, which we
// use on platforms that don't support the GC's atomicity protocols. That means anything other
// than X86-64 and ARM64. This scheduler is a drop-in replacement for the concurrent GC's
// SpaceTimeMutatorScheduler. It tells the GC to never resume the world once the GC cycle begins.
class SynchronousStopTheWorldMutatorScheduler final : public MutatorScheduler {
public:
SynchronousStopTheWorldMutatorScheduler();
~SynchronousStopTheWorldMutatorScheduler() final;
State state() const final;
void beginCollection() final;
MonotonicTime timeToStop() final;
MonotonicTime timeToResume() final;
void endCollection() final;
private:
State m_state { Normal };
};
} // namespace JSC
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