[Bug tree-optimization/81611] [8 Regression] gcc un-learned loop / post-increment optimization

[aoliva at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81611

--- Comment #11 from Alexandre Oliva <aoliva at gcc dot gnu.org> ---
Testing has revealed that the alternative complementary candidate patch
introduces a number of regressions, in tests intended specifically to detect
this kind of problem.  I don't see an easy way to delay the post-increment at
gimplification time, so I'm dropping this approach altogether.  Back to
exploring other possibilities, perhaps even extending auto_inc_dec, or... 
something else, I don't know.