r3 100 gc/darwin_stop_world.c GC_push_one(state.r3); r3 183 gc/darwin_stop_world.c GC_push_one(info.r3); r3 358 gc/win32_threads.c # define PUSH4(r1,r2,r3,r4) PUSH2(r1,r2), PUSH2(r3,r4)