Source/JavaScriptCore/heap/MarkingConstraint.cpp

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#include "config.h"
#include "MarkingConstraint.h"

#include "JSCInlines.h"
#include "VisitCounter.h"

namespace JSC {

static constexpr bool verboseMarkingConstraint = false;

MarkingConstraint::MarkingConstraint(CString abbreviatedName, CString name, ConstraintVolatility volatility, ConstraintConcurrency concurrency, ConstraintParallelism parallelism)
    : m_abbreviatedName(abbreviatedName)
    , m_name(WTFMove(name))
    , m_volatility(volatility)
    , m_concurrency(concurrency)
    , m_parallelism(parallelism)
{
}

MarkingConstraint::~MarkingConstraint()
{
}

void MarkingConstraint::resetStats()
{
    m_lastVisitCount = 0;
}

void MarkingConstraint::execute(SlotVisitor& visitor)
{
    ASSERT(!visitor.heap()->isMarkingForGCVerifier());
    VisitCounter visitCounter(visitor);
    executeImpl(visitor);
    m_lastVisitCount += visitCounter.visitCount();
    if (verboseMarkingConstraint && visitCounter.visitCount())
        dataLog("(", abbreviatedName(), " visited ", visitCounter.visitCount(), " in execute)");
}

void MarkingConstraint::executeSynchronously(AbstractSlotVisitor& visitor)
{
    prepareToExecuteImpl(NoLockingNecessary, visitor);
    executeImpl(visitor);
}

double MarkingConstraint::quickWorkEstimate(SlotVisitor&)
{
    return 0;
}

double MarkingConstraint::workEstimate(SlotVisitor& visitor)
{
    return lastVisitCount() + quickWorkEstimate(visitor);
}

void MarkingConstraint::prepareToExecute(const AbstractLocker& constraintSolvingLocker, SlotVisitor& visitor)
{
    ASSERT(!visitor.heap()->isMarkingForGCVerifier());
    dataLogIf(Options::logGC(), abbreviatedName());
    VisitCounter visitCounter(visitor);
    prepareToExecuteImpl(constraintSolvingLocker, visitor);
    m_lastVisitCount = visitCounter.visitCount();
    if (verboseMarkingConstraint && visitCounter.visitCount())
        dataLog("(", abbreviatedName(), " visited ", visitCounter.visitCount(), " in prepareToExecute)");
}

void MarkingConstraint::doParallelWork(SlotVisitor& visitor, SharedTask<void(SlotVisitor&)>& task)
{
    ASSERT(!visitor.heap()->isMarkingForGCVerifier());
    VisitCounter visitCounter(visitor);
    task.run(visitor);
    if (verboseMarkingConstraint && visitCounter.visitCount())
        dataLog("(", abbreviatedName(), " visited ", visitCounter.visitCount(), " in doParallelWork)");
    {
        auto locker = holdLock(m_lock);
        m_lastVisitCount += visitCounter.visitCount();
    }
}

void MarkingConstraint::prepareToExecuteImpl(const AbstractLocker&, AbstractSlotVisitor&)
{
}

} // namespace JSC