void SlotVisitor::drain()
{
StackStats::probe();
ASSERT(m_isInParallelMode);
#if ENABLE(PARALLEL_GC)
if (Options::numberOfGCMarkers() > 1) {
while (!m_stack.isEmpty()) {
m_stack.refill();
for (unsigned countdown = Options::minimumNumberOfScansBetweenRebalance(); m_stack.canRemoveLast() && countdown--;)
visitChildren(*this, m_stack.removeLast());
donateKnownParallel();
}
mergeOpaqueRootsIfNecessary();
return;
}
#endif
while (!m_stack.isEmpty()) {
m_stack.refill();
while (m_stack.canRemoveLast())
visitChildren(*this, m_stack.removeLast());
}
}
void SlotVisitor::donate()
{
ASSERT(m_isInParallelMode);
if (Options::numberOfGCMarkers() == 1)
return;
donateKnownParallel();
}
void SlotVisitor::drain()
{
ASSERT(m_isInParallelMode);
while (!m_stack.isEmpty()) {
m_stack.refill();
for (unsigned countdown = Options::minimumNumberOfScansBetweenRebalance(); m_stack.canRemoveLast() && countdown--;)
visitChildren(m_stack.removeLast());
donateKnownParallel();
}
mergeOpaqueRootsIfNecessary();
}
void SlotVisitor::drain(MonotonicTime timeout)
{
ASSERT(m_isInParallelMode);
while ((!m_collectorStack.isEmpty() || !m_mutatorStack.isEmpty()) && !hasElapsed(timeout)) {
if (!m_collectorStack.isEmpty()) {
m_collectorStack.refill();
m_isVisitingMutatorStack = false;
for (unsigned countdown = Options::minimumNumberOfScansBetweenRebalance(); m_collectorStack.canRemoveLast() && countdown--;)
visitChildren(m_collectorStack.removeLast());
} else if (!m_mutatorStack.isEmpty()) {
m_mutatorStack.refill();
// We know for sure that we are visiting objects because of the barrier, not because of
// marking. Marking will visit an object exactly once. The barrier will visit it
// possibly many times, and always after it was already marked.
m_isVisitingMutatorStack = true;
for (unsigned countdown = Options::minimumNumberOfScansBetweenRebalance(); m_mutatorStack.canRemoveLast() && countdown--;)
visitChildren(m_mutatorStack.removeLast());
}
donateKnownParallel();
}
mergeOpaqueRootsIfNecessary();
}
void SlotVisitor::donateKnownParallel()
{
donateKnownParallel(m_collectorStack, *m_heap.m_sharedCollectorMarkStack);
donateKnownParallel(m_mutatorStack, *m_heap.m_sharedMutatorMarkStack);
}
