gcc:

[pf3gnuchains/gcc-fork.git] / gcc / cfghooks.c

diff --git a/gcc/cfghooks.c b/gcc/cfghooks.c
index 0897b0d..ad5fb6b 100644 (file)
--- a/gcc/cfghooks.c
+++ b/gcc/cfghooks.c
@@ -425,6 +425,7 @@ edge
 split_block (basic_block bb, void *i)
 {
   basic_block new_bb;
+  edge res;
 
   if (!cfg_hooks->split_block)
     internal_error ("%s does not support split_block", cfg_hooks->name);
@@ -436,6 +437,7 @@ split_block (basic_block bb, void *i)
   new_bb->count = bb->count;
   new_bb->frequency = bb->frequency;
   new_bb->loop_depth = bb->loop_depth;
+  new_bb->discriminator = bb->discriminator;
 
   if (dom_info_available_p (CDI_DOMINATORS))
     {
@@ -450,7 +452,15 @@ split_block (basic_block bb, void *i)
        bb->loop_father->latch = new_bb;
     }
 
-  return make_single_succ_edge (bb, new_bb, EDGE_FALLTHRU);
+  res = make_single_succ_edge (bb, new_bb, EDGE_FALLTHRU);
+
+  if (bb->flags & BB_IRREDUCIBLE_LOOP)
+    {
+      new_bb->flags |= BB_IRREDUCIBLE_LOOP;
+      res->flags |= EDGE_IRREDUCIBLE_LOOP;
+    }
+
+  return res;
 }
 
 /* Splits block BB just after labels.  The newly created edge is returned.  */
@@ -760,7 +770,7 @@ make_forwarder_block (basic_block bb, bool (*redirect_edge_p) (edge),
               && dummy->loop_father->header == dummy
               && dummy->loop_father->latch == e_src)
             dummy->loop_father->latch = jump;
-          
+
           if (new_bb_cbk != NULL)
             new_bb_cbk (jump);
         }
@@ -820,7 +830,7 @@ tidy_fallthru_edge (edge e)
 /* Fix up edges that now fall through, or rather should now fall through
    but previously required a jump around now deleted blocks.  Simplify
    the search by only examining blocks numerically adjacent, since this
-   is how find_basic_blocks created them.  */
+   is how they were created.  */
 
 void
 tidy_fallthru_edges (void)
@@ -843,9 +853,9 @@ tidy_fallthru_edges (void)
         a single successor.
 
         If we had a conditional branch to the next instruction when
-        find_basic_blocks was called, then there will only be one
-        out edge for the block which ended with the conditional
-        branch (since we do not create duplicate edges).
+        CFG was built, then there will only be one out edge for the
+        block which ended with the conditional branch (since we do
+        not create duplicate edges).
 
         Furthermore, the edge will be marked as a fallthru because we
         merge the flags for the duplicate edges.  So we do not want to