optabs.c (prepare_operand): Gracefully fail if the mode of X does not match the…

optabs.c (prepare_operand): Gracefully fail if the mode of X does not match the operand mode expected by...

	* optabs.c (prepare_operand): Gracefully fail if the mode of X
	does not match the operand mode expected by the insn pattern.

From-SVN: r217501

gcc/ChangeLog

+2014-11-13  Ulrich Weigand  <Ulrich.Weigand@de.ibm.com>
+
+	* optabs.c (prepare_operand): Gracefully fail if the mode of X
+	does not match the operand mode expected by the insn pattern.
+
 2014-11-13  Richard Biener  <rguenther@suse.de>
 
 	* match.pd: Add tcc_comparison, inverted_tcc_comparison

gcc/optabs.c

@@ -4308,9 +4308,12 @@ prepare_operand (enum insn_code icode, rtx x, int opnum, machine_mode mode,
 
   if (!insn_operand_matches (icode, opnum, x))
     {
+      machine_mode op_mode = insn_data[(int) icode].operand[opnum].mode;
       if (reload_completed)
 	return NULL_RTX;
-      x = copy_to_mode_reg (insn_data[(int) icode].operand[opnum].mode, x);
+      if (GET_MODE (x) != op_mode && GET_MODE (x) != VOIDmode)
+	return NULL_RTX;
+      x = copy_to_mode_reg (op_mode, x);
     }
 
   return x;