[Bug rtl-optimization/25196] [4.0/4.1 Regression] i386: wrong arguments passed

["steven at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>]

------- 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