Source/JavaScriptCore/heap/GCIncomingRefCountedSetInlines.h

/*
 * Copyright (C) 2013 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
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 *    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,
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 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
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 */

#pragma once

#include "GCIncomingRefCountedSet.h"
#include "VM.h"

namespace JSC {

template<typename T>
GCIncomingRefCountedSet<T>::GCIncomingRefCountedSet()
    : m_bytes(0)
{
}

template<typename T>
void GCIncomingRefCountedSet<T>::lastChanceToFinalize()
{
    for (size_t i = m_vector.size(); i--;)
        m_vector[i]->filterIncomingReferences([] (JSCell*) { return false; });
}

template<typename T>
bool GCIncomingRefCountedSet<T>::addReference(JSCell* cell, T* object)
{
    if (!object->addIncomingReference(cell)) {
        ASSERT(object->isDeferred());
        ASSERT(object->numberOfIncomingReferences());
        return false;
    }
    m_vector.append(object);
    m_bytes += object->gcSizeEstimateInBytes();
    ASSERT(object->isDeferred());
    ASSERT(object->numberOfIncomingReferences());
    return true;
}

template<typename T>
void GCIncomingRefCountedSet<T>::sweep(VM& vm)
{
    for (size_t i = 0; i < m_vector.size(); ++i) {
        T* object = m_vector[i];
        size_t size = object->gcSizeEstimateInBytes();
        ASSERT(object->isDeferred());
        ASSERT(object->numberOfIncomingReferences());
        if (!object->filterIncomingReferences([&] (JSCell* cell) { return vm.heap.isMarked(cell); }))
            continue;
        m_bytes -= size;
        m_vector[i--] = m_vector.last();
        m_vector.removeLast();
    }

    constexpr bool verify = false;
    if constexpr (verify) {
        CheckedSize size;
        for (size_t i = m_vector.size(); i--;) {
            T* object = m_vector[i];
            size += object->gcSizeEstimateInBytes();
        }
        ASSERT(m_bytes == size);
    }
}

template<typename T>
void GCIncomingRefCountedSet<T>::reduceSize(size_t bytes)
{
    ASSERT(m_bytes >= bytes);
    m_bytes -= bytes;
}

} // namespace JSC