cfgrtl.c (force_nonfallthru_and_redirect): Allow abnormal edge to be forced into nonfallthru.

	* cfgrtl.c (force_nonfallthru_and_redirect):  Allow abnormal edge
	to be forced into nonfallthru.

From-SVN: r59816

gcc/ChangeLog

+Wed Dec  4 15:20:54 CET 2002  Jan Hubicka  <jh@suse.cz>
+
+	* cfgrtl.c (force_nonfallthru_and_redirect):  Allow abnormal edge
+	to be forced into nonfallthru.
+
 2002-12-03  Jason Thorpe  <thorpej@wasabisystems.com>
 
 	* config/t-netbsd (USER_H): Set to $(EXTRA_HEADERS).

gcc/cfgrtl.c

@@ -933,12 +933,23 @@ force_nonfallthru_and_redirect (e, target)
      edge e;
      basic_block target;
 {
-  basic_block jump_block, new_bb = NULL;
+  basic_block jump_block, new_bb = NULL, src = e->src;
   rtx note;
   edge new_edge;
+  int abnormal_edge_flags = 0;
 
   if (e->flags & EDGE_ABNORMAL)
-    abort ();
+    {
+      /* Irritating special case - fallthru edge to the same block as abnormal
+	 edge.
+	 We can't redirect abnormal edge, but we still can split the fallthru
+	 one and create separate abnormal edge to original destination. 
+	 This allows bb-reorder to make such edge non-fallthru.  */
+      if (e->dest != target)
+	abort ();
+      abnormal_edge_flags = e->flags & ~(EDGE_FALLTHRU | EDGE_CAN_FALLTHRU);
+      e->flags &= EDGE_FALLTHRU | EDGE_CAN_FALLTHRU;
+    }
   else if (!(e->flags & EDGE_FALLTHRU))
     abort ();
   else if (e->src == ENTRY_BLOCK_PTR)
@@ -962,7 +973,7 @@ force_nonfallthru_and_redirect (e, target)
       make_single_succ_edge (ENTRY_BLOCK_PTR, bb, EDGE_FALLTHRU);
     }
 
-  if (e->src->succ->succ_next)
+  if (e->src->succ->succ_next || abnormal_edge_flags)
     {
       /* Create the new structures.  */
 
@@ -1029,6 +1040,9 @@ force_nonfallthru_and_redirect (e, target)
   emit_barrier_after (jump_block->end);
   redirect_edge_succ_nodup (e, target);
 
+  if (abnormal_edge_flags)
+    make_edge (src, target, abnormal_edge_flags);
+
   return new_bb;
 }