(ashldi3_const_int): Don't recognize if won't match constraint of

operand 2.

From-SVN: r11661

gcc/config/i386/i386.md

@@ -4077,7 +4077,7 @@
   [(set (match_operand:DI 0 "register_operand" "=&r")
 	(ashift:DI (match_operand:DI 1 "register_operand" "0")
 		   (match_operand:QI 2 "const_int_operand" "J")))]
-  ""
+  "CONST_OK_FOR_LETTER_P (INTVAL (operands[2]), 'J')"
   "*
 {
   rtx xops[4], low[1], high[1];