simplify-rtx.c (simplify_const_relational_operation): When extracting arguments…

simplify-rtx.c (simplify_const_relational_operation): When extracting arguments of a COMPARE, recompute the mode as well.

	* simplify-rtx.c (simplify_const_relational_operation): When
	extracting arguments of a COMPARE, recompute the mode as well.

From-SVN: r103143

gcc/ChangeLog

+2005-08-15  Ulrich Weigand  <uweigand@de.ibm.com>
+
+	* simplify-rtx.c (simplify_const_relational_operation): When
+	extracting arguments of a COMPARE, recompute the mode as well.
+
 2005-08-15  Ian Lance Taylor  <ian@airs.com>
 
 	* tree.c (build_string): Mark tree CONSTANT and INVARIANT.

gcc/simplify-rtx.c

@@ -3014,7 +3014,17 @@ simplify_const_relational_operation (enum rtx_code code,
 
   /* If op0 is a compare, extract the comparison arguments from it.  */
   if (GET_CODE (op0) == COMPARE && op1 == const0_rtx)
-    op1 = XEXP (op0, 1), op0 = XEXP (op0, 0);
+    {
+      op1 = XEXP (op0, 1);
+      op0 = XEXP (op0, 0);
+
+      if (GET_MODE (op0) != VOIDmode)
+	mode = GET_MODE (op0);
+      else if (GET_MODE (op1) != VOIDmode)
+	mode = GET_MODE (op1);
+      else
+	return 0;
+    }
 
   /* We can't simplify MODE_CC values since we don't know what the
      actual comparison is.  */