PT_BRANCH_P
if (!PT_BRANCH_P(node))
KASSERT(PT_BRANCH_P(node) || id->id_parent_slot == PTN_LEAF_POSITION(ptn));
KASSERT(PT_BRANCH_P(node) || id->id_parent_slot == PTN_LEAF_POSITION(PT_NODE(node)));
KASSERT(PT_BRANCH_P(id.id_node));
if (PT_BRANCH_P(node)) {
if (PT_BRANCH_P(node)