Do not check the if-convertibility of statements that are not predicated.

2010-05-26  Sebastian Pop  <sebastian.pop@amd.com>

	* tree-if-conv.c (if_convertible_gimple_assign_stmt_p): Do not
	special case loop->header.
	(is_predicated): New.
	(if_convertible_loop_p): Call it.

From-SVN: r159887

gcc/ChangeLog

 2010-05-26  Sebastian Pop  <sebastian.pop@amd.com>
 
+	* tree-if-conv.c (if_convertible_gimple_assign_stmt_p): Do not
+	special case loop->header.
+	(is_predicated): New.
+	(if_convertible_loop_p): Call it.
+
+2010-05-26  Sebastian Pop  <sebastian.pop@amd.com>
+
 	* tree-if-conv.c (add_to_dst_predicate_list): Do not pass a statemet
 	iterator in parameter.  Do not generate code during the analysis.
 	(tree_if_convert_cond_stmt): Removed.

gcc/tree-if-conv.c

@@ -274,9 +274,7 @@ if_convertible_gimple_assign_stmt_p (struct loop *loop, basic_block bb,
       return false;
     }
 
-  /* See if it needs speculative loading or not.  */
-  if (bb != loop->header
-      && gimple_assign_rhs_could_trap_p (stmt))
+  if (gimple_assign_rhs_could_trap_p (stmt))
     {
       if (dump_file && (dump_flags & TDF_DETAILS))
 	fprintf (dump_file, "tree could trap...\n");
@@ -588,6 +586,19 @@ predicate_bbs (loop_p loop)
   return true;
 }
 
+/* Returns true when BB has a predicate that is not trivial: true or
+   NULL_TREE.  */
+
+static bool
+is_predicated (basic_block bb)
+{
+  tree cond = (tree) bb->aux;
+
+  return (cond != NULL_TREE
+	  && cond != boolean_true_node
+	  && !integer_onep (cond));
+}
+
 /* Return true when LOOP is if-convertible.
    LOOP is if-convertible if:
    - it is innermost,
@@ -682,6 +693,10 @@ if_convertible_loop_p (struct loop *loop)
       basic_block bb = ifc_bbs[i];
       gimple_stmt_iterator itr;
 
+      /* For non predicated BBs, don't check their statements.  */
+      if (!is_predicated (bb))
+	continue;
+
       for (itr = gsi_start_bb (bb); !gsi_end_p (itr); gsi_next (&itr))
 	if (!if_convertible_stmt_p (loop, bb, gsi_stmt (itr)))
 	  return false;