arm.c (arm_rtx_costs_1): Handle mutiply-subtract.

2007-01-10  Paul Brook  <paul@codesourcery.com>

	gcc/
	* config/arm/arm.c (arm_rtx_costs_1): Handle mutiply-subtract.
	* config/arm/arm.md (mulsi3subsi): New insn.

From-SVN: r120651

gcc/ChangeLog

+2007-01-10  Paul Brook  <paul@codesourcery.com>
+
+	* config/arm/arm.c (arm_rtx_costs_1): Handle mutiply-subtract.
+	* config/arm/arm.md (mulsi3subsi): New insn.
+
 2007-01-10  Zdenek Dvorak <dvorakz@suse.cz>
 
 	* tree-ssa-loop-manip.c (tree_unroll_loop): Make it a wrapper over ...

gcc/config/arm/arm.c

@@ -4752,6 +4752,14 @@ arm_rtx_costs_1 (rtx x, enum rtx_code code, enum rtx_code outer)
 		 ? 0 : 4));
 
     case MINUS:
+      if (GET_CODE (XEXP (x, 1)) == MULT && mode == SImode && arm_arch_thumb2)
+	{
+	  extra_cost = rtx_cost (XEXP (x, 1), code);
+	  if (!REG_OR_SUBREG_REG (XEXP (x, 0)))
+	    extra_cost += 4 * ARM_NUM_REGS (mode);
+	  return extra_cost;
+	}
+
       if (mode == DImode)
 	return (4 + (REG_OR_SUBREG_REG (XEXP (x, 1)) ? 0 : 8)
 		+ ((REG_OR_SUBREG_REG (XEXP (x, 0))

gcc/config/arm/arm.md

@@ -1294,6 +1294,18 @@
    (set_attr "insn" "mlas")]
 )
 
+(define_insn "*mulsi3subsi"
+  [(set (match_operand:SI 0 "s_register_operand" "=r")
+	(minus:SI
+	  (match_operand:SI 3 "s_register_operand" "r")
+	  (mult:SI (match_operand:SI 2 "s_register_operand" "r")
+		   (match_operand:SI 1 "s_register_operand" "r"))))]
+  "TARGET_32BIT && arm_arch_thumb2"
+  "mls%?\\t%0, %2, %1, %3"
+  [(set_attr "insn" "mla")
+   (set_attr "predicable" "yes")]
+)
+
 ;; Unnamed template to match long long multiply-accumulate (smlal)
 
 (define_insn "*mulsidi3adddi"