[Bug middle-end/52996] [4.8 Regression] ice in verify_loop_structure, at cfgloop.c:1567

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52996



--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> 2012-12-21 
12:47:54 UTC ---

Ick, I had



Index: gcc/cprop.c

===================================================================

--- gcc/cprop.c (revision 194658)

+++ gcc/cprop.c (working copy)

@@ -1554,8 +1554,7 @@ bypass_block (basic_block bb, rtx setcc,

       /* The irreducible loops created by redirecting of edges entering the

         loop from outside would decrease effectiveness of some of the

         following optimizations, so prevent this.  */

-      if (may_be_loop_header

-         && !(e->flags & EDGE_DFS_BACK))

+      if (may_be_loop_header)

        {

          ei_next (&ei);

          continue;



in my tree ...