[Bug tree-optimization/25243] [4.1/4.2 Regression] Jump threading opportunity missed in tree-ssa but caught in jump1

["pinskia at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #4 from pinskia at gcc dot gnu dot org  2005-12-03 17:01 -------
This looks very much related to PR 21829.

Hmm, in 4.0.0 we got Before DOM (likewise for 4.1.0 and above):
<L1>:;
  i_2 = i_10 + 1;
  if (i_2 != 4) goto <L0>; else goto <L3>;

  # i_7 = PHI <i_2(2)>;
<L3>:;
  if (i_7 == 4) goto <L4>; else goto <L5>;

but after:
<L1>:;
  i_2 = i_10 + 1;
  if (i_2 != 4) goto <L0>; else goto <L3>;

Invalid sum of incoming frequencies 2375, should be 0
  # i_7 = PHI <i_2(2)>;
<L3>:;
  foo (r_3);

Which means that GCC got it right in 4.0.0


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  BugsThisDependsOn|                            |21829
      Known to fail|                            |4.1.0 4.2.0
      Known to work|                            |4.0.0 4.0.2
            Summary|Jump threading opportunity  |[4.1/4.2 Regression] Jump
                   |missed in tree-ssa but      |threading opportunity missed
                   |caught in jump1             |in tree-ssa but caught in
                   |                            |jump1
   Target Milestone|---                         |4.2.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25243