Daily bump.

[pf3gnuchains/gcc-fork.git] / gcc / tree-ssa-loop-ch.c

diff --git a/gcc/tree-ssa-loop-ch.c b/gcc/tree-ssa-loop-ch.c
index 9a0dca7..48799d7 100644 (file)
--- a/gcc/tree-ssa-loop-ch.c
+++ b/gcc/tree-ssa-loop-ch.c
@@ -1,18 +1,18 @@
 /* Loop header copying on trees.
-   Copyright (C) 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
-   
+   Copyright (C) 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
+
 This file is part of GCC.
-   
+
 GCC is free software; you can redistribute it and/or modify it
 under the terms of the GNU General Public License as published by the
 Free Software Foundation; either version 3, or (at your option) any
 later version.
-   
+
 GCC is distributed in the hope that it will be useful, but WITHOUT
 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 for more details.
-   
+
 You should have received a copy of the GNU General Public License
 along with GCC; see the file COPYING3.  If not see
 <http://www.gnu.org/licenses/>.  */
@@ -22,9 +22,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "coretypes.h"
 #include "tm.h"
 #include "tree.h"
-#include "rtl.h"
 #include "tm_p.h"
-#include "hard-reg-set.h"
 #include "basic-block.h"
 #include "output.h"
 #include "diagnostic.h"
@@ -58,6 +56,13 @@ should_duplicate_loop_header_p (basic_block header, struct loop *loop,
   if (header->aux)
     return false;
 
+  /* Loop header copying usually increases size of the code.  This used not to
+     be true, since quite often it is possible to verify that the condition is
+     satisfied in the first iteration and therefore to eliminate it.  Jump
+     threading handles these cases now.  */
+  if (optimize_loop_for_size_p (loop))
+    return false;
+
   gcc_assert (EDGE_COUNT (header->succs) > 0);
   if (single_succ_p (header))
     return false;
@@ -83,6 +88,9 @@ should_duplicate_loop_header_p (basic_block header, struct loop *loop,
       if (gimple_code (last) == GIMPLE_LABEL)
        continue;
 
+      if (is_gimple_debug (last))
+       continue;
+
       if (is_gimple_call (last))
        return false;
 
@@ -253,7 +261,7 @@ gate_ch (void)
   return flag_tree_ch != 0;
 }
 
-struct gimple_opt_pass pass_ch = 
+struct gimple_opt_pass pass_ch =
 {
  {
   GIMPLE_PASS,
@@ -268,7 +276,7 @@ struct gimple_opt_pass pass_ch =
   0,                                   /* properties_provided */
   0,                                   /* properties_destroyed */
   0,                                   /* todo_flags_start */
-  TODO_cleanup_cfg | TODO_dump_func 
+  TODO_cleanup_cfg | TODO_dump_func
   | TODO_verify_ssa                    /* todo_flags_finish */
  }
 };