NODE_COUNT
ASSERT(NODE_COUNT(atomic_load_relaxed(&node->state)) < LEVEL_SIZE);
ASSERT(NODE_COUNT(atomic_load_relaxed(&node->state)) > 0);
ASSERT(NODE_COUNT(atomic_load_relaxed(&node->state)) <= LEVEL_SIZE);
NODE_COUNT(atomic_load_relaxed(&parent->state)) == 0) {
if (NODE_COUNT(atomic_load_relaxed(&parent->state)) == 0) {