------- Comment #8 from steven at gcc dot gnu dot org 2005-12-20 15:58 ------- Gross. According to a comment in postreload.c:move2add_note_store(), we can have pushes without REG_INC notes: /* Some targets do argument pushes without adding REG_INC notes. */
So we need to go look for those {pre,post}{decrements,increments} ourselves. With this patch, we just do what postreload.c does. Index: postreload-gcse.c =================================================================== --- postreload-gcse.c (revision 108853) +++ postreload-gcse.c (working copy) @@ -676,6 +676,17 @@ record_last_set_info (rtx dest, rtx sett /* Ignore pushes, they clobber nothing. */ && ! push_operand (dest, GET_MODE (dest))) record_last_mem_set_info (last_set_insn); + + /* ??? Some targets do argument pushes without adding REG_INC notes. + See e.g. PR25196, where a pushsi2 on i386 doesn't have REG_INC + notes. */ + if (MEM_P (dest)) + { + dest = XEXP (dest, 0); + if (GET_CODE (dest) == PRE_INC || GET_CODE (dest) == POST_INC + || GET_CODE (dest) == PRE_DEC || GET_CODE (dest) == POST_DEC) + record_last_reg_set_info (last_set_insn, REGNO (XEXP (dest, 0))); + } } -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25196