Use reset_bb_predicate whenever the predicate of a BB should be reset to true.

2010-06-25  Sebastian Pop  <sebastian.pop@amd.com>

	* tree-if-conv.c (init_bb_predicate): Initialize the predicate
	to boolean_true_node.
	(reset_bb_predicate): New.
	(predicate_bbs): Call reset_bb_predicate.

From-SVN: r161397

gcc/ChangeLog

 2010-06-25  Sebastian Pop  <sebastian.pop@amd.com>
 
+	* tree-if-conv.c (init_bb_predicate): Initialize the predicate
+	to boolean_true_node.
+	(reset_bb_predicate): New.
+	(predicate_bbs): Call reset_bb_predicate.
+
+2010-06-25  Sebastian Pop  <sebastian.pop@amd.com>
+
 	* tree-if-conv.c (combine_blocks): Remove FIXME comment.
 	(tree_if_conversion): Returns true when something has been changed.
 	(main_tree_if_conversion): Return TODO_cleanup_cfg when if-conversion

gcc/tree-if-conv.c

@@ -175,7 +175,7 @@ init_bb_predicate (basic_block bb)
 {
   bb->aux = XNEW (struct bb_predicate_s);
   set_bb_predicate_gimplified_stmts (bb, NULL);
-  set_bb_predicate (bb, NULL_TREE);
+  set_bb_predicate (bb, boolean_true_node);
 }
 
 /* Free the predicate of basic block BB.  */
@@ -203,6 +203,16 @@ free_bb_predicate (basic_block bb)
   bb->aux = NULL;
 }
 
+/* Free the predicate of BB and reinitialize it with the true
+   predicate.  */
+
+static inline void
+reset_bb_predicate (basic_block bb)
+{
+  free_bb_predicate (bb);
+  init_bb_predicate (bb);
+}
+
 /* Create a new temp variable of type TYPE.  Add GIMPLE_ASSIGN to assign EXP
    to the new variable.  */
 
@@ -605,8 +615,7 @@ predicate_bbs (loop_p loop)
 	 to be processed: skip it.  */
       if (bb == loop->latch)
 	{
-	  set_bb_predicate (loop->latch, boolean_true_node);
-	  set_bb_predicate_gimplified_stmts (loop->latch, NULL);
+	  reset_bb_predicate (loop->latch);
 	  continue;
 	}
 
@@ -680,7 +689,7 @@ predicate_bbs (loop_p loop)
     }
 
   /* The loop header is always executed.  */
-  set_bb_predicate (loop->header, boolean_true_node);
+  reset_bb_predicate (loop->header);
   gcc_assert (bb_predicate_gimplified_stmts (loop->header) == NULL
 	      && bb_predicate_gimplified_stmts (loop->latch) == NULL);