MarkStackMergingConstraint.cpp   [plain text]

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#include "config.h"
#include "MarkStackMergingConstraint.h"

#include "GCSegmentedArrayInlines.h"
#include "JSCInlines.h"

namespace JSC {

MarkStackMergingConstraint::MarkStackMergingConstraint(Heap& heap)
    : MarkingConstraint("Msm", "Mark Stack Merging", ConstraintVolatility::GreyedByExecution)
    , m_heap(heap)
{
}

MarkStackMergingConstraint::~MarkStackMergingConstraint()
{
}

double MarkStackMergingConstraint::quickWorkEstimate(SlotVisitor&)
{
    return m_heap.m_mutatorMarkStack->size() + m_heap.m_raceMarkStack->size();
}

void MarkStackMergingConstraint::prepareToExecuteImpl(const AbstractLocker&, SlotVisitor& visitor)
{
    // Logging the work here ensures that the constraint solver knows that it doesn't need to produce
    // anymore work.
    size_t size = m_heap.m_mutatorMarkStack->size() + m_heap.m_raceMarkStack->size();
    visitor.addToVisitCount(size);
    
    if (Options::logGC())
        dataLog("(", size, ")");
}

void MarkStackMergingConstraint::executeImpl(SlotVisitor& visitor)
{
    m_heap.m_mutatorMarkStack->transferTo(visitor.mutatorMarkStack());
    m_heap.m_raceMarkStack->transferTo(visitor.mutatorMarkStack());
}

} // namespace JSC