simplify-rtx.c (simplify_rtx): Canonicalize commutative expressions by putting…

simplify-rtx.c (simplify_rtx): Canonicalize commutative expressions by putting complex operands first and...

        * simplify-rtx.c (simplify_rtx): Canonicalize commutative expressions
        by putting complex operands first and constants second.

From-SVN: r43621

gcc/ChangeLog

+Wed Jun 27 18:01:09 2001  Jeffrey A Law  (law@cygnus.com)
+
+	* simplify-rtx.c (simplify_rtx): Canonicalize commutative expressions
+	by putting complex operands first and constants second.
+
 2001-06-27  Gabriel Dos Reis  <gdr@codesourcery.com>
 
 	* diagnostic.h: Add documentation. Make macros polymorphic.

gcc/simplify-rtx.c

@@ -2520,8 +2520,26 @@ simplify_rtx (x)
     case '1':
       return simplify_unary_operation (code, mode,
 				       XEXP (x, 0), GET_MODE (XEXP (x, 0)));
-    case '2':
     case 'c':
+      /* Put complex operands first and constants second if commutative.  */
+      if (GET_RTX_CLASS (code) == 'c'
+	  && ((CONSTANT_P (XEXP (x, 0)) && GET_CODE (XEXP (x, 1)) != CONST_INT)
+	      || (GET_RTX_CLASS (GET_CODE (XEXP (x, 0))) == 'o'
+		  && GET_RTX_CLASS (GET_CODE (XEXP (x, 1))) != 'o')
+	      || (GET_CODE (XEXP (x, 0)) == SUBREG
+		  && GET_RTX_CLASS (GET_CODE (SUBREG_REG (XEXP (x, 0)))) == 'o'
+		  && GET_RTX_CLASS (GET_CODE (XEXP (x, 1))) != 'o')))
+	{
+	  rtx tem;
+
+	  tem = XEXP (x, 0);
+	  XEXP (x, 0) = XEXP (x, 1);
+	  XEXP (x, 1) = tem;
+	  return simplify_binary_operation (code, mode,
+					    XEXP (x, 0), XEXP (x, 1));
+	}
+
+    case '2':
       return simplify_binary_operation (code, mode, XEXP (x, 0), XEXP (x, 1));
 
     case '3':