FOR_EACH_PRED     234 gc/backgraph.c       FOR_EACH_PRED(pred, q, { if (p == pred) return; });
FOR_EACH_PRED     368 gc/backgraph.c   FOR_EACH_PRED(q, p, {
FOR_EACH_PRED     412 gc/backgraph.c     FOR_EACH_PRED(q, p, {