2006-12-13 Richard Guenther <rguenther@suse.de>

[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 5cf2f92..e1d5af8 100644 (file)
--- a/gcc/tree-ssa-loop-ch.c
+++ b/gcc/tree-ssa-loop-ch.c
@@ -1,5 +1,5 @@
 /* Loop header copying on trees.
-   Copyright (C) 2004 Free Software Foundation, Inc.
+   Copyright (C) 2004, 2005 Free Software Foundation, Inc.
    
 This file is part of GCC.
    
@@ -15,8 +15,8 @@ for more details.
    
 You should have received a copy of the GNU General Public License
 along with GCC; see the file COPYING.  If not, write to the Free
-Software Foundation, 59 Temple Place - Suite 330, Boston, MA
-02111-1307, USA.  */
+Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301, USA.  */
 
 #include "config.h"
 #include "system.h"
@@ -60,7 +60,7 @@ should_duplicate_loop_header_p (basic_block header, struct loop *loop,
     return false;
 
   gcc_assert (EDGE_COUNT (header->succs) > 0);
-  if (EDGE_COUNT (header->succs) == 1)
+  if (single_succ_p (header))
     return false;
   if (flow_bb_inside_loop_p (loop, EDGE_SUCC (header, 0)->dest)
       && flow_bb_inside_loop_p (loop, EDGE_SUCC (header, 1)->dest))
@@ -68,7 +68,7 @@ should_duplicate_loop_header_p (basic_block header, struct loop *loop,
 
   /* If this is not the original loop header, we want it to have just
      one predecessor in order to match the && pattern.  */
-  if (header != loop->header && EDGE_COUNT (header->preds) >= 2)
+  if (header != loop->header && !single_pred_p (header))
     return false;
 
   last = last_stmt (header);
@@ -120,40 +120,35 @@ do_while_loop_p (struct loop *loop)
    of the loop.  This is beneficial since it increases efficiency of
    code motion optimizations.  It also saves one jump on entry to the loop.  */
 
-static void
+static unsigned int
 copy_loop_headers (void)
 {
-  struct loops *loops;
-  unsigned i;
+  loop_iterator li;
   struct loop *loop;
   basic_block header;
-  edge exit;
-  basic_block *bbs;
+  edge exit, entry;
+  basic_block *bbs, *copied_bbs;
   unsigned n_bbs;
+  unsigned bbs_size;
 
-  loops = loop_optimizer_init (dump_file);
-  if (!loops)
-    return;
-  rewrite_into_loop_closed_ssa (NULL);
-  
-  /* We do not try to keep the information about irreducible regions
-     up-to-date.  */
-  loops->state &= ~LOOPS_HAVE_MARKED_IRREDUCIBLE_REGIONS;
+  loop_optimizer_init (LOOPS_HAVE_PREHEADERS
+                      | LOOPS_HAVE_SIMPLE_LATCHES);
+  if (!current_loops)
+    return 0;
 
 #ifdef ENABLE_CHECKING
-  verify_loop_structure (loops);
+  verify_loop_structure ();
 #endif
 
-  bbs = xmalloc (sizeof (basic_block) * n_basic_blocks);
+  bbs = XNEWVEC (basic_block, n_basic_blocks);
+  copied_bbs = XNEWVEC (basic_block, n_basic_blocks);
+  bbs_size = n_basic_blocks;
 
-  for (i = 1; i < loops->num; i++)
+  FOR_EACH_LOOP (li, loop, 0)
     {
       /* Copy at most 20 insns.  */
       int limit = 20;
 
-      loop = loops->parray[i];
-      if (!loop)
-       continue;
       header = loop->header;
 
       /* If the loop is already a do-while style one (either because it was
@@ -180,6 +175,7 @@ copy_loop_headers (void)
          else
            exit = EDGE_SUCC (header, 1);
          bbs[n_bbs++] = header;
+         gcc_assert (bbs_size > n_bbs);
          header = exit->dest;
        }
 
@@ -193,11 +189,12 @@ copy_loop_headers (void)
 
       /* Ensure that the header will have just the latch as a predecessor
         inside the loop.  */
-      if (EDGE_COUNT (exit->dest->preds) > 1)
-       exit = EDGE_SUCC (loop_split_edge_with (exit, NULL), 0);
+      if (!single_pred_p (exit->dest))
+       exit = single_pred_edge (split_edge (exit));
+
+      entry = loop_preheader_edge (loop);
 
-      if (!tree_duplicate_sese_region (loop_preheader_edge (loop), exit,
-                                      bbs, n_bbs, NULL))
+      if (!tree_duplicate_sese_region (entry, exit, bbs, n_bbs, copied_bbs))
        {
          fprintf (dump_file, "Duplication failed.\n");
          continue;
@@ -205,17 +202,15 @@ copy_loop_headers (void)
 
       /* Ensure that the latch and the preheader is simple (we know that they
         are not now, since there was the loop exit condition.  */
-      loop_split_edge_with (loop_preheader_edge (loop), NULL);
-      loop_split_edge_with (loop_latch_edge (loop), NULL);
+      split_edge (loop_preheader_edge (loop));
+      split_edge (loop_latch_edge (loop));
     }
 
   free (bbs);
+  free (copied_bbs);
 
-#ifdef ENABLE_CHECKING
-  verify_loop_closed_ssa ();
-#endif
-
-  loop_optimizer_finalize (loops, NULL);
+  loop_optimizer_finalize ();
+  return 0;
 }
 
 static bool