===================================================================
@@ -1068,14 +1068,7 @@ find_inc (bool first_try)
/* For the post_add to work, the result_reg of the inc must not be
used in the mem insn since this will become the new index
register. */
- if (count_occurrences (PATTERN (mem_insn.insn), inc_insn.reg_res, 1) == 0
- && reg_overlap_mentioned_p (inc_insn.reg_res, PATTERN (mem_insn.insn)))
- {
- debug_rtx (mem_insn.insn);
- debug_rtx (inc_insn.reg_res);
- gcc_unreachable ();
- }
- if (count_occurrences (PATTERN (mem_insn.insn), inc_insn.reg_res, 1) != 0)
+ if (reg_overlap_mentioned_p (inc_insn.reg_res, PATTERN (mem_insn.insn)))
{
if (dump_file)
fprintf (dump_file, "base reg replacement failure.\n");
Kazu recently made a change in auto-inc-dec.c to avoid using count_occurrences in one case, since it doesn't handle hard registers correctly. There was a patch posted at http://gcc.gnu.org/ml/gcc-patches/2010-06/msg00514.html which looks correct, but a different patch was checked in: @@ -1068,6 +1068,13 @@ find_inc (bool first_try) /* For the post_add to work, the result_reg of the inc must not be used in the mem insn since this will become the new index register. */ + if (count_occurrences (PATTERN (mem_insn.insn), inc_insn.reg_res, 1) == 0 + && reg_overlap_mentioned_p (inc_insn.reg_res, PATTERN (mem_insn.insn))) + { + debug_rtx (mem_insn.insn); + debug_rtx (inc_insn.reg_res); + gcc_unreachable (); + } if (count_occurrences (PATTERN (mem_insn.insn), inc_insn.reg_res, 1) != 0) { if (dump_file) which isn't actually fixing anything, just causing an abort when we encounter the problematic situation. This triggers on the PR44404 testcase if my ARM ldm/stm peephole patch is applied. I'll be checking in the below as obvious after some testing. There are some more calls to count_occurrences in auto-inc-dec.c which worry me a bit, but that's a problem for another day. Bernd PR rtl-optimization/44404 * auto-inc-dec.c (find_inc): Avoid calling count_occurrences if possible, use reg_overlap_mentioned_p instead.