[Bug tree-optimization/54458] [4.8 Regression] ICE get_loop_body, at cfgloop.c:830

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54458

--- Comment #7 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-09-03 
14:27:27 UTC ---
I'm testing

Index: gcc/tree-ssa-threadupdate.c
===================================================================
--- gcc/tree-ssa-threadupdate.c (revision 190889)
+++ gcc/tree-ssa-threadupdate.c (working copy)
@@ -1037,11 +1037,21 @@ thread_through_loop_header (struct loop
        }
       free (bblocks);

+      /* If the new header has multiple latches mark it so.  */
+      FOR_EACH_EDGE (e, ei, loop->header->preds)
+       if (e->src->loop_father == loop
+           && e->src != loop->latch)
+         {
+           loop->latch = NULL;
+           loops_state_set (LOOPS_MAY_HAVE_MULTIPLE_LATCHES);
+         }
+
       /* Cancel remaining threading requests that would make the
         loop a multiple entry loop.  */
       FOR_EACH_EDGE (e, ei, header->preds)