ifcvt.c (noce_try_store_flag_mask): Check rtx cost.

ChangeLog:
2014-11-03  Zhenqiang Chen  <zhenqiang.chen@arm.com>

	* ifcvt.c (noce_try_store_flag_mask): Check rtx cost.

testsuite/ChangeLog:
2014-11-03  Zhenqiang Chen  <zhenqiang.chen@arm.com>

	* gcc.target/arm/ifcvt-size-check.c: New test.

From-SVN: r217029

gcc/ChangeLog

+2014-11-03  Zhenqiang Chen  <zhenqiang.chen@arm.com>
+
+	* ifcvt.c (noce_try_store_flag_mask): Check rtx cost.
+
 2014-11-03  Andrew Pinski  <apinski@cavium.com>
 
 	* config/mips/mips-cpus.def (octeon3): New cpu.

gcc/ifcvt.c

@@ -1394,6 +1394,9 @@ noce_try_store_flag_mask (struct noce_if_info *if_info)
 
       if (target)
 	{
+	  int old_cost, new_cost, insn_cost;
+	  int speed_p;
+
 	  if (target != if_info->x)
 	    noce_emit_move_insn (if_info->x, target);
 
@@ -1401,6 +1404,14 @@ noce_try_store_flag_mask (struct noce_if_info *if_info)
 	  if (!seq)
 	    return FALSE;
 
+	  speed_p = optimize_bb_for_speed_p (BLOCK_FOR_INSN (if_info->insn_a));
+	  insn_cost = insn_rtx_cost (PATTERN (if_info->insn_a), speed_p);
+	  old_cost = COSTS_N_INSNS (if_info->branch_cost) + insn_cost;
+	  new_cost = seq_cost (seq, speed_p);
+
+	  if (new_cost > old_cost)
+	    return FALSE;
+
 	  emit_insn_before_setloc (seq, if_info->jump,
 				   INSN_LOCATION (if_info->insn_a));
 	  return TRUE;

gcc/testsuite/ChangeLog

+2014-11-03  Zhenqiang Chen  <zhenqiang.chen@arm.com>
+
+	* gcc.target/arm/ifcvt-size-check.c: New test.
+
 2014-11-03  Naveen H.S  <Naveen.Hurugalawadi@caviumnetworks.com>
 
 	* gcc.target/mips/octeon3-pipe-1.c: New test.

gcc/testsuite/gcc.target/arm/ifcvt-size-check.c

+/* { dg-do assemble } */
+/* { dg-options "-mthumb -Os " }  */
+/* { dg-require-effective-target arm_thumb1_ok } */
+
+int
+test (unsigned char iov_len, int count, int i)
+{
+  unsigned char bytes = 0;
+  if ((unsigned char) ((char) 127 - bytes) < iov_len)
+    return 22;
+  return 0;
+}
+/* { dg-final { object-size text <= 12 } } */