Source/JavaScriptCore/runtime/CachedSpecialPropertyAdaptiveStructureWatchpoint.cpp

/*
 * Copyright (C) 2019-2020 Apple Inc. All rights reserved.
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#include "config.h"
#include "CachedSpecialPropertyAdaptiveStructureWatchpoint.h"

#include "JSCellInlines.h"
#include "StructureRareData.h"

namespace JSC {

CachedSpecialPropertyAdaptiveStructureWatchpoint::CachedSpecialPropertyAdaptiveStructureWatchpoint(const ObjectPropertyCondition& key, StructureRareData* structureRareData)
    : Watchpoint(Watchpoint::Type::CachedSpecialPropertyAdaptiveStructure)
    , m_structureRareData(structureRareData)
    , m_key(key)
{
    RELEASE_ASSERT(key.watchingRequiresStructureTransitionWatchpoint());
    RELEASE_ASSERT(!key.watchingRequiresReplacementWatchpoint());
}

void CachedSpecialPropertyAdaptiveStructureWatchpoint::install(VM&)
{
    RELEASE_ASSERT(m_key.isWatchable(PropertyCondition::MakeNoChanges));

    m_key.object()->structure()->addTransitionWatchpoint(this);
}

void CachedSpecialPropertyAdaptiveStructureWatchpoint::fireInternal(VM& vm, const FireDetail&)
{
    if (!m_structureRareData->isLive())
        return;

    if (m_key.isWatchable(PropertyCondition::EnsureWatchability)) {
        install(vm);
        return;
    }

    CachedSpecialPropertyKey key = CachedSpecialPropertyKey::ToStringTag;
    if (m_key.uid() == vm.propertyNames->toStringTagSymbol.impl())
        key = CachedSpecialPropertyKey::ToStringTag;
    else if (m_key.uid() == vm.propertyNames->toString.impl())
        key = CachedSpecialPropertyKey::ToString;
    else if (m_key.uid() == vm.propertyNames->valueOf.impl())
        key = CachedSpecialPropertyKey::ValueOf;
    else if (m_key.uid() == vm.propertyNames->toJSON.impl())
        key = CachedSpecialPropertyKey::ToJSON;
    else {
        ASSERT(m_key.uid() == vm.propertyNames->toPrimitiveSymbol.impl());
        key = CachedSpecialPropertyKey::ToPrimitive;
    }

    m_structureRareData->clearCachedSpecialProperty(key);
}

} // namespace JSC