Source/JavaScriptCore/heap/GCActivityCallback.h

/*
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 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
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#pragma once

#include "JSRunLoopTimer.h"
#include "Synchronousness.h"
#include <wtf/RefPtr.h>

namespace JSC {

class FullGCActivityCallback;
class Heap;

class GCActivityCallback : public JSRunLoopTimer {
public:
    using Base = JSRunLoopTimer;

    JS_EXPORT_PRIVATE GCActivityCallback(Heap&, Synchronousness);
    JS_EXPORT_PRIVATE ~GCActivityCallback();

    JS_EXPORT_PRIVATE void doWork(VM&) override;

    virtual void doCollection(VM&) = 0;

    void didAllocate(Heap&, size_t);
    void willCollect();
    JS_EXPORT_PRIVATE void cancel();
    bool isEnabled() const { return m_enabled; }
    void setEnabled(bool enabled) { m_enabled = enabled; }
    bool didGCRecently() const { return m_didGCRecently; }
    void setDidGCRecently(bool didGCRecently) { m_didGCRecently = didGCRecently; }

    static bool s_shouldCreateGCTimer;

protected:
    virtual Seconds lastGCLength(Heap&) = 0;
    virtual double gcTimeSlice(size_t bytes) = 0;
    virtual double deathRate(Heap&) = 0;
    JS_EXPORT_PRIVATE void scheduleTimer(Seconds);

    GCActivityCallback(VM&, Synchronousness);

    Synchronousness m_synchronousness { Synchronousness::Async };
    bool m_enabled { true };
    bool m_didGCRecently { false };
    Seconds m_delay { s_decade };
};

} // namespace JSC