Re: More fp bug in egcs

[hjl@lucon.org (H.J. Lu)]

> 
> One reason for keeping output reloads, even though the register is dead, is
> for debugging purposes.  With your patch, it looks like debugging of 
> unoptimized code would not work right.  It would be OK to do this
> when optimizing, but that would not fix the x86 bug.
> 

If the register is clobbered, isn't the value in it random? If it is
tru, how can it help debugging? I changed my patch to omit the output
reload if it is in the source and is clobbered. Does it look safe?


-- 
H.J. Lu (hjl@gnu.org)
----
Sun May  3 18:44:40 1998  H.J. Lu  (hjl@gnu.org)

	* reload1.c (emit_reload_insns): Don't output the last reload
	insn if OLD is the src of INSN and is clobbered by INSN.

--- ../../../import/egcs/gcc/reload1.c	Mon Apr 20 08:23:47 1998
+++ ./reload1.c	Sun May  3 18:57:26 1998
@@ -6730,8 +6730,17 @@ emit_reload_insns (insn)
 
 	  /* Output the last reload insn.  */
 	  if (! special)
-	    gen_reload (old, reloadreg, reload_opnum[j],
-			reload_when_needed[j]);
+	    {
+	      rtx set;
+
+	      /* Don't output the last reload if OLD is the src of INSN
+		 and is clobbered by INSN. */
+	      if (GET_CODE (old) != REG || !(set = single_set (insn))
+		  || !reg_mentioned_p (old, SET_SRC (set))
+		  || !regno_clobbered_p (REGNO (old), insn))
+		gen_reload (old, reloadreg, reload_opnum[j],
+			    reload_when_needed[j]);
+	    }
 
 #ifdef PRESERVE_DEATH_INFO_REGNO_P
 	  /* If final will look at death notes for this reg,