[Bug tree-optimization/84648] Missed optimization : loop not removed.

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84648

--- Comment #4 from bin cheng <amker at gcc dot gnu.org> ---
Author: amker
Date: Thu Nov 15 03:44:49 2018
New Revision: 266171

URL: https://gcc.gnu.org/viewcvs?rev=266171&root=gcc&view=rev
Log:

        PR tree-optimization/84648
        * tree-ssa-loop-niter.c (adjust_cond_for_loop_until_wrap): New.
        (number_of_iterations_cond): Adjust exit cond for loop-until-wrap case
        by calling adjust_cond_for_loop_until_wrap.

        gcc/testsuite
        * gcc.dg/tree-ssa/pr84648.c: New test.
        * gcc.dg/pr68317.c: Add warning check on overflow.


Added:
    trunk/gcc/testsuite/gcc.dg/tree-ssa/pr84648.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gcc.dg/pr68317.c
    trunk/gcc/tree-ssa-loop-niter.c