simplify-rtx.c (simplify_subreg): Allow volatile memory to be subregged in case…

simplify-rtx.c (simplify_subreg): Allow volatile memory to be subregged in case we don't have move instruction.

	* simplify-rtx.c (simplify_subreg): Allow volatile memory
	to be subregged in case we don't have move instruction.

From-SVN: r43261

gcc/ChangeLog

+Tue Jun 12 17:24:07 CEST 2001  Jan Hubicka  <jh@suse.cz>
+
+	* simplify-rtx.c (simplify_subreg): Allow volatile memory
+	to be subregged in case we don't have move instruction.
+
+Tue Jun 12 12:20:12 CEST 2001  Jan Hubicka  <jh@suse.cz>
+
+	* loop.c: Include predict.h
+	(strength_reduce): Drop branch prediction note in case
+	number of iterations is known.
+	* predict.def (PRED_LOOP_ITERATIONS): new.
+	* Makefile.in (loop.o): Add dependancy on predict.h
+
 2001-06-12  Kaveh R. Ghazi  <ghazi@caip.rutgers.edu>
 
 	* c-decl.c (grokdeclarator): Use INTEGRAL_TYPE_P.

gcc/simplify-rtx.c

@@ -2409,7 +2409,11 @@ simplify_subreg (outermode, op, innermode, byte)
 
   if (GET_CODE (op) == MEM
       && ! mode_dependent_address_p (XEXP (op, 0))
-      && ! MEM_VOLATILE_P (op)
+      /* Allow splitting of volatile memory references in case we don't
+         have instruction to move the whole thing.  */
+      && (! MEM_VOLATILE_P (op)
+	  || (mov_optab->handlers[(int) innermode].insn_code
+	      == CODE_FOR_nothing))
       && GET_MODE_SIZE (outermode) <= GET_MODE_SIZE (GET_MODE (op)))
     {
       rtx new;