arm.c (thumb1_size_rtx_costs): Assign proper cost for shift_add/shift_sub0/shift_sub1 RTXs.

gcc/ChangeLog:
2013-07-24  Terry Guo  <terry.guo@arm.com>

	* config/arm/arm.c (thumb1_size_rtx_costs): Assign proper cost for
	shift_add/shift_sub0/shift_sub1 RTXs.

gcc/testsuite/ChangeLog:
2013-07-24  Terry Guo  <terry.guo@arm.com>

	* gcc.target/arm/thumb1-Os-mult.c: New test case.

From-SVN: r201237

gcc/ChangeLog

+2013-07-25  Terry Guo  <terry.guo@arm.com>
+
+	* config/arm/arm.c (thumb1_size_rtx_costs): Assign proper cost for
+	shift_add/shift_sub0/shift_sub1 RTXs.
+
 2013-07-24  Bill Schmidt  <wschmidt@linux.ibm.com>
 	    Anton Blanchard <anton@au1.ibm.com>
 

gcc/config/arm/arm.c

@@ -7925,6 +7925,15 @@ thumb1_size_rtx_costs (rtx x, enum rtx_code code, enum rtx_code outer)
 
     case PLUS:
     case MINUS:
+      /* Thumb-1 needs two instructions to fulfill shiftadd/shiftsub0/shiftsub1
+	 defined by RTL expansion, especially for the expansion of
+	 multiplication.  */
+      if ((GET_CODE (XEXP (x, 0)) == MULT
+	   && power_of_two_operand (XEXP (XEXP (x,0),1), SImode))
+	  || (GET_CODE (XEXP (x, 1)) == MULT
+	      && power_of_two_operand (XEXP (XEXP (x, 1), 1), SImode)))
+	return COSTS_N_INSNS (2);
+      /* On purpose fall through for normal RTX.  */
     case COMPARE:
     case NEG:
     case NOT:

gcc/testsuite/ChangeLog

+2013-07-25  Terry Guo  <terry.guo@arm.com>
+
+	* gcc.target/arm/thumb1-Os-mult.c: New test case.
+
 2013-07-24  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	PR c++/57942

gcc/testsuite/gcc.target/arm/thumb1-Os-mult.c

+/* { dg-require-effective-target arm_thumb1_ok } */
+/* { dg-do compile } */
+/* { dg-options "-Os" } */
+/* { dg-skip-if "" { ! { arm_thumb1 } } } */
+
+int
+mymul3 (int x)
+{
+  return x * 0x555;
+}
+
+/* { dg-final { scan-assembler "mul\[\\t \]*r.,\[\\t \]*r." } } */