function.c (purge_addressof_1): Add libcall check.

2003-11-11  Eric Christopher  <echristo@redhat.com>

	* function.c (purge_addressof_1): Add libcall check.
	Remove test for cached replacements on fallback case.
	Simplify mode comparisons. Add libcall test for
	paradoxical subregs.

From-SVN: r73479

gcc/ChangeLog

+2003-11-11  Eric Christopher  <echristo@redhat.com>
+
+	* function.c (purge_addressof_1): Add libcall check.
+	Remove test for cached replacements on fallback case.
+	Simplify mode comparisons. Add libcall test for
+	paradoxical subregs.
+
 2003-11-11  Kazu Hirata  <kazu@cs.umass.edu>
 
 	* config/h8300/t-h8300: Fix an obsolete comment.

gcc/function.c

@@ -2929,6 +2929,7 @@ purge_addressof_1 (rtx *loc, rtx insn, int force, int store, int may_postpone,
   int i, j;
   const char *fmt;
   bool result = true;
+  bool libcall = false;
 
   /* Re-start here to avoid recursion in common cases.  */
  restart:
@@ -2937,6 +2938,10 @@ purge_addressof_1 (rtx *loc, rtx insn, int force, int store, int may_postpone,
   if (x == 0)
     return true;
 
+  /* Is this a libcall?  */
+  if (!insn)
+    libcall = REG_NOTE_KIND (*loc) == REG_RETVAL;
+
   code = GET_CODE (x);
 
   /* If we don't return in any of the cases below, we will recurse inside
@@ -3070,31 +3075,27 @@ purge_addressof_1 (rtx *loc, rtx insn, int force, int store, int may_postpone,
 		 which can be succinctly described with a simple SUBREG.
 		 Note that removing the REG_EQUAL note is not an option
 		 on the last insn of a libcall, so we must do a replacement.  */
-	      if (! purge_addressof_replacements
-		  && ! purge_bitfield_addressof_replacements)
-		{
+
 	      /* In compile/990107-1.c:7 compiled at -O1 -m1 for sh-elf,
 		 we got
 		 (mem:DI (addressof:SI (reg/v:DF 160) 159 0x401c8510)
 		 [0 S8 A32]), which can be expressed with a simple
 		 same-size subreg  */
 	      if ((GET_MODE_SIZE (GET_MODE (x))
-		       == GET_MODE_SIZE (GET_MODE (sub)))
+		   <= GET_MODE_SIZE (GET_MODE (sub)))
 		  /* Again, invalid pointer casts (as in
 		     compile/990203-1.c) can require paradoxical
 		     subregs.  */
 		  || (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
 		      && (GET_MODE_SIZE (GET_MODE (x))
-			      > GET_MODE_SIZE (GET_MODE (sub))))
-		      || (GET_MODE_SIZE (GET_MODE (x))
-			  < GET_MODE_SIZE (GET_MODE (sub))))
-
+			  > GET_MODE_SIZE (GET_MODE (sub)))
+		      && libcall))
 		{
 		  *loc = gen_rtx_SUBREG (GET_MODE (x), sub, 0);
 		  return true;
 		}
 	      /* ??? Are there other cases we should handle?  */
-		}
+
 	      /* Sometimes we may not be able to find the replacement.  For
 		 example when the original insn was a MEM in a wider mode,
 		 and the note is part of a sign extension of a narrowed