[ARM][2/4] Fix operand costing logic for SMUL[TB][TB]

	PR target/65932
	PR target/67714
	* config/arm/arm.c (arm_new_rtx_costs, MULT case): Properly extract
	the operands of the SIGN_EXTENDs from a SMUL[TB][TB] rtx.

From-SVN: r233132

gcc/ChangeLog

+2016-02-04  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
+
+	PR target/65932
+	PR target/67714
+	* config/arm/arm.c (arm_new_rtx_costs, MULT case): Properly extract
+	the operands of the SIGN_EXTENDs from a SMUL[TB][TB] rtx.
+
 2016-02-04  Jim Wilson  <jim.wilson@linaro.org>
 
 	PR target/65932

gcc/config/arm/arm.c

@@ -10318,8 +10318,10 @@ arm_new_rtx_costs (rtx x, enum rtx_code code, enum rtx_code outer_code,
 	      /* SMUL[TB][TB].  */
 	      if (speed_p)
 		*cost += extra_cost->mult[0].extend;
-	      *cost += rtx_cost (XEXP (x, 0), mode, SIGN_EXTEND, 0, speed_p);
-	      *cost += rtx_cost (XEXP (x, 1), mode, SIGN_EXTEND, 1, speed_p);
+	      *cost += rtx_cost (XEXP (XEXP (x, 0), 0), mode,
+				 SIGN_EXTEND, 0, speed_p);
+	      *cost += rtx_cost (XEXP (XEXP (x, 1), 0), mode,
+				 SIGN_EXTEND, 1, speed_p);
 	      return true;
 	    }
 	  if (speed_p)