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From: "cvs-commit at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/111019] [12/13/14 Regression] Optimizer incorrectly assumes
 variable is not changed while change happens through another pointer
Date: Fri, 18 Aug 2023 13:05:11 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D111019

--- Comment #10 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Richard Biener <rguenth@gcc.gnu.org>:

https://gcc.gnu.org/g:745ec2135aabfbe2c0fb7780309837d17e8986d4

commit r14-3325-g745ec2135aabfbe2c0fb7780309837d17e8986d4
Author: Richard Biener <rguenther@suse.de>
Date:   Thu Aug 17 15:21:33 2023 +0200

    tree-optimization/111019 - invariant motion and aliasing

    The following fixes a bad choice in representing things to the alias
    oracle by LIM which while correct in pieces is inconsistent with itself.
    When canonicalizing a ref to a bare deref instead of leaving the base
    object and the extracted offset the same and just substituting an
    alternate ref the following replaces the base and the offset as well,
    avoiding the confusion that otherwise will arise in
    aliasing_matching_component_refs_p.

            PR tree-optimization/111019
            * tree-ssa-loop-im.cc (gather_mem_refs_stmt): When canonicalizi=
ng
            also scrap base and offset in case the ref is indirect.

            * g++.dg/torture/pr111019.C: New testcase.=