tree-ssa-copyrename.c (copy_rename_partition_coalesce): Return true when something was changed.

	* tree-ssa-copyrename.c (copy_rename_partition_coalesce): Return
	true when something was changed.
	(rename_ssa_copies): When something was changed, do
	TODO_remove_unused_locals.
	* tree-ssa-forwprop.c (tree_ssa_forward_propagate_single_use_value):
	add TODO_remove_unused_locals when instruction was removed.

From-SVN: r121571

1 files changed, 16 insertions, 14 deletions

diff --git a/gcc/tree-ssa-copyrename.c b/gcc/tree-ssa-copyrename.c
index 2311afa..e06de4c 100644
--- a/gcc/tree-ssa-copyrename.c
+++ b/gcc/tree-ssa-copyrename.c
@@ -109,7 +109,7 @@ Boston, MA 02110-1301, USA.  */
 /* Coalesce the partitions in MAP representing VAR1 and VAR2 if it is valid.
    Choose a representative for the partition, and send debug info to DEBUG.  */
 
-static void
+static bool
 copy_rename_partition_coalesce (var_map map, tree var1, tree var2, FILE *debug)
 {
   int p1, p2, p3;
@@ -151,7 +151,7 @@ copy_rename_partition_coalesce (var_map map, tree var1, tree var2, FILE *debug)
     {
       if (debug)
 	fprintf (debug, " : Already coalesced.\n");
-      return;
+      return false;
     }
 
   /* Don't coalesce if one of the variables occurs in an abnormal PHI.  */
@@ -161,7 +161,7 @@ copy_rename_partition_coalesce (var_map map, tree var1, tree var2, FILE *debug)
     {
       if (debug)
 	fprintf (debug, " : Abnormal PHI barrier.  No coalesce.\n");
-      return;
+      return false;
     }
 
   /* Partitions already have the same root, simply merge them.  */
@@ -170,7 +170,7 @@ copy_rename_partition_coalesce (var_map map, tree var1, tree var2, FILE *debug)
       p1 = partition_union (map->var_partition, p1, p2);
       if (debug)
 	fprintf (debug, " : Same root, coalesced --> P%d.\n", p1);
-      return;
+      return false;
     }
 
   /* Never attempt to coalesce 2 difference parameters.  */
@@ -178,14 +178,14 @@ copy_rename_partition_coalesce (var_map map, tree var1, tree var2, FILE *debug)
     {
       if (debug)
         fprintf (debug, " : 2 different PARM_DECLS. No coalesce.\n");
-      return;
+      return false;
     }
 
   if ((TREE_CODE (root1) == RESULT_DECL) != (TREE_CODE (root2) == RESULT_DECL))
     {
       if (debug)
         fprintf (debug, " : One root a RESULT_DECL. No coalesce.\n");
-      return;
+      return false;
     }
 
   ign1 = TREE_CODE (root1) == VAR_DECL && DECL_IGNORED_P (root1);
@@ -203,7 +203,7 @@ copy_rename_partition_coalesce (var_map map, tree var1, tree var2, FILE *debug)
 	{
 	  if (debug)
 	    fprintf (debug, " : 2 different USER vars. No coalesce.\n");
-	  return;
+	  return false;
 	}
     }
 
@@ -214,7 +214,7 @@ copy_rename_partition_coalesce (var_map map, tree var1, tree var2, FILE *debug)
     {
       if (debug)
 	fprintf (debug, " : 2 memory tags. No coalesce.\n");
-      return;
+      return false;
     }
 
   /* If both values have default defs, we can't coalesce.  If only one has a 
@@ -225,7 +225,7 @@ copy_rename_partition_coalesce (var_map map, tree var1, tree var2, FILE *debug)
 	{
 	  if (debug)
 	    fprintf (debug, " : 2 default defs. No coalesce.\n");
-	  return;
+	  return false;
 	}
       else
         {
@@ -244,7 +244,7 @@ copy_rename_partition_coalesce (var_map map, tree var1, tree var2, FILE *debug)
     {
       if (debug)
 	fprintf (debug, " : Incompatible types.  No coalesce.\n");
-      return;
+      return false;
     }
 
   /* Don't coalesce if the aliasing sets of the types are different.  */
@@ -255,7 +255,7 @@ copy_rename_partition_coalesce (var_map map, tree var1, tree var2, FILE *debug)
     {
       if (debug)
 	fprintf (debug, " : 2 different aliasing sets. No coalesce.\n");
-      return;
+      return false;
     }
 
 
@@ -283,6 +283,7 @@ copy_rename_partition_coalesce (var_map map, tree var1, tree var2, FILE *debug)
 			  TDF_SLIM);
       fprintf (debug, "\n");
     }
+  return true;
 }
 
 
@@ -301,6 +302,7 @@ rename_ssa_copies (void)
   tree phi, stmt, var, part_var;
   unsigned x;
   FILE *debug;
+  bool updated = false;
 
   if (dump_file && (dump_flags & TDF_DETAILS))
     debug = dump_file;
@@ -321,7 +323,7 @@ rename_ssa_copies (void)
 	      tree rhs = GIMPLE_STMT_OPERAND (stmt, 1);
 
               if (TREE_CODE (lhs) == SSA_NAME && TREE_CODE (rhs) == SSA_NAME)
-		copy_rename_partition_coalesce (map, lhs, rhs, debug);
+		updated |= copy_rename_partition_coalesce (map, lhs, rhs, debug);
 	    }
 	}
     }
@@ -342,7 +344,7 @@ rename_ssa_copies (void)
             {
               tree arg = PHI_ARG_DEF (phi, i);
               if (TREE_CODE (arg) == SSA_NAME)
-		copy_rename_partition_coalesce (map, res, arg, debug);
+		updated |= copy_rename_partition_coalesce (map, res, arg, debug);
             }
         }
     }
@@ -374,7 +376,7 @@ rename_ssa_copies (void)
     }
 
   delete_var_map (map);
-  return 0;
+  return updated ? TODO_remove_unused_locals : 0;
 }
 
 /* Return true if copy rename is to be performed.  */