> I suspect the bulk of them currently are coming from the safe_as_a > <rtx_insn *> calls within NEXT_INSN and PREV_INSN; do you happen to have > information handy on that?
Yes that's right: - 1.03% lto1 [.] bool is_a_helper<rtx_insn*>::test<rtx_def>(rtx_def*) ▒ - bool is_a_helper<rtx_insn*>::test<rtx_def>(rtx_def*) ▒ - 92.20% bool is_a<rtx_insn*, rtx_def>(rtx_def*) ▒ - 98.53% rtx_insn* safe_as_a<rtx_insn*, rtx_def>(rtx_def*) ▒ - 73.28% NEXT_INSN(rtx_insn const*) ▒