[Bug tree-optimization/88301] [8 Regression] Optimization regression with undefined unsigned overflow

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88301

--- Comment #7 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Mon Dec  3 13:38:20 2018
New Revision: 266739

URL: https://gcc.gnu.org/viewcvs?rev=266739&root=gcc&view=rev
Log:
2018-12-03  Richard Biener  <rguenther@suse.de>

        PR tree-optimization/88301
        * tree-vrp.c (register_edge_assert_for_2): Handle conversions
        that do not change the value by registering the same assert
        for the operand.

        * gcc.dg/tree-ssa/evrp13.c: New testcase.

Added:
    trunk/gcc/testsuite/gcc.dg/tree-ssa/evrp13.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-vrp.c