mips.c (mips_rtx_costs): Fix cost estimate for nor (AND (NOT OP1) (NOT OP2)).

2013-10-22  Steve Ellcey  <sellcey@mips.com>

	* config/mips/mips.c (mips_rtx_costs):  Fix cost estimate for nor
	(AND (NOT OP1) (NOT OP2)).

From-SVN: r203932

gcc/ChangeLog

+2013-10-22  Steve Ellcey  <sellcey@mips.com>
+
+	* config/mips/mips.c (mips_rtx_costs):  Fix cost estimate for nor
+	(AND (NOT OP1) (NOT OP2)).
+
 2013-10-22  Bill Schmidt  <wschmidt@vnet.ibm.com>
 
 	* config/rs6000/rs6000.c (altivec_expand_vec_perm_const): Reverse

gcc/config/mips/mips.c

@@ -3796,6 +3796,18 @@ mips_rtx_costs (rtx x, int code, int outer_code, int opno ATTRIBUTE_UNUSED,
 	      return true;
 	    }
 	}
+      /* (AND (NOT op0) (NOT op1) is a nor operation that can be done in
+	 a single instruction.  */
+      if (!TARGET_MIPS16
+	  && GET_CODE (XEXP (x, 0)) == NOT
+	  && GET_CODE (XEXP (x, 1)) == NOT)
+	{
+	  cost = GET_MODE_SIZE (mode) > UNITS_PER_WORD ? 2 : 1;
+          *total = (COSTS_N_INSNS (cost)
+		    + set_src_cost (XEXP (XEXP (x, 0), 0), speed)
+		    + set_src_cost (XEXP (XEXP (x, 1), 0), speed));
+	  return true;
+	}
 	    
       /* Fall through.  */