[Bug tree-optimization/69615] 0 to limit signed range checks don't always use unsigned compare

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69615

--- Comment #7 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Author: jakub
Date: Mon Jun  4 07:37:56 2018
New Revision: 261139

URL: https://gcc.gnu.org/viewcvs?rev=261139&root=gcc&view=rev
Log:
        PR tree-optimization/69615
        * fold-const.c (merge_ranges): If range1 is - [x, x] and x is the
        maximum or minimum of the type, try to merge it also as if
        range1 is + [-, x - 1] or + [x + 1, -].

        * gcc.dg/pr69615.c: New test.

Added:
    trunk/gcc/testsuite/gcc.dg/pr69615.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/fold-const.c
    trunk/gcc/testsuite/ChangeLog