tree-ssa-loop-im.c (determine_max_movement): Adjust cost of PHI node moving.

2014-06-17  Richard Biener  <rguenther@suse.de>

	* tree-ssa-loop-im.c (determine_max_movement): Adjust cost
	of PHI node moving.

	* gcc.dg/tree-ssa/ssa-lim-12.c: New testcase.

From-SVN: r211724

gcc/ChangeLog

+2014-06-17  Richard Biener  <rguenther@suse.de>
+
+	* tree-ssa-loop-im.c (determine_max_movement): Adjust cost
+	of PHI node moving.
+
 2014-06-17  Kugan Vivekanandarajah  <kuganv@linaro.org>
 
 	* config/arm/arm.c (arm_atomic_assign_expand_fenv): call

gcc/testsuite/ChangeLog

+2014-06-17  Richard Biener  <rguenther@suse.de>
+
+	* gcc.dg/tree-ssa/ssa-lim-12.c: New testcase.
+
 2014-06-16  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/61482

gcc/testsuite/gcc.dg/tree-ssa/ssa-lim-12.c

+/* { dg-do compile } */
+/* { dg-options "-O -fdump-tree-lim1" } */
+
+int a[1024];
+
+void foo (int x, int z)
+{
+  int i;
+  int y = -x;
+  for (i = 0; i < 1024; ++i)
+    a[i] = x ? y : z;
+}
+
+void bar (int x, int z)
+{
+  int j;
+  for (j = 0; j < 1024; ++j)
+    {
+      int i;
+      int y = -j + z;
+      for (i = 0; i < 1024; ++i)
+	a[i] = x ? y : j;
+    }
+}
+
+/* { dg-final { scan-tree-dump-times "!= 0 ? " 2 "lim1" } } */
+/* { dg-final { cleanup-tree-dump "lim1" } } */

gcc/tree-ssa-loop-im.c

@@ -729,14 +729,21 @@ determine_max_movement (gimple stmt, bool must_preserve_exec)
 	    }
 	  if (!add_dependency (val, lim_data, loop, false))
 	    return false;
-	  def_data = get_lim_data (SSA_NAME_DEF_STMT (val));
-	  if (def_data)
+
+	  gimple def_stmt = SSA_NAME_DEF_STMT (val);
+	  if (gimple_bb (def_stmt)
+	      && gimple_bb (def_stmt)->loop_father == loop)
 	    {
-	      min_cost = MIN (min_cost, def_data->cost);
-	      total_cost += def_data->cost;
+	      def_data = get_lim_data (def_stmt);
+	      if (def_data)
+		{
+		  min_cost = MIN (min_cost, def_data->cost);
+		  total_cost += def_data->cost;
+		}
 	    }
 	}
 
+      min_cost = MIN (min_cost, total_cost);
       lim_data->cost += min_cost;
 
       if (gimple_phi_num_args (stmt) > 1)