[Bug tree-optimization/91294] [10 Regression] wrong strlen result of a conditional with an offset

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91294

--- Comment #3 from Martin Sebor <msebor at gcc dot gnu.org> ---
Author: msebor
Date: Wed Aug 14 16:27:59 2019
New Revision: 274486

URL: https://gcc.gnu.org/viewcvs?rev=274486&root=gcc&view=rev
Log:
PR tree-optimization/91294 - [10 Regression] wrong strlen result of a
conditional with an offset

gcc/testsuite/ChangeLog:

        PR tree-optimization/91294
        * gcc.dg/strlenopt-44.c: Adjust tested result.
        * gcc.dg/strlenopt-70.c: Avoid exercising unimplemnted optimization.
        * gcc.dg/strlenopt-73.c: New test.
        * gcc.dg/strlenopt-74.c: New test.
        * gcc.dg/strlenopt-75.c: New test.
        * gcc.dg/strlenopt-76.c: New test.
        * gcc.dg/strlenopt-77.c: New test.

gcc/ChangeLog:

        PR tree-optimization/91294
        * tree-ssa-strlen.c (handle_store): Avoid treating lower bound of
        source length as exact.

Added:
    trunk/gcc/testsuite/gcc.dg/strlenopt-73.c
    trunk/gcc/testsuite/gcc.dg/strlenopt-74.c
    trunk/gcc/testsuite/gcc.dg/strlenopt-75.c
    trunk/gcc/testsuite/gcc.dg/strlenopt-76.c
    trunk/gcc/testsuite/gcc.dg/strlenopt-77.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/gimple-fold.c
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gcc.dg/strlenopt-44.c
    trunk/gcc/testsuite/gcc.dg/strlenopt-70.c
    trunk/gcc/tree-ssa-strlen.c
    trunk/gcc/tree-ssa-strlen.h