[Bug middle-end/102566] [i386] GCC should emit LOCK BTS for simple bit-test-and-set operations with std::atomic

[cvs-commit at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102566

--- Comment #35 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by H.J. Lu <h...@gcc.gnu.org>:

https://gcc.gnu.org/g:03ed4e57e3d46a61513b3d1ab1720997aec8cf71

commit r13-3760-g03ed4e57e3d46a61513b3d1ab1720997aec8cf71
Author: H.J. Lu <hjl.to...@gmail.com>
Date:   Tue Nov 1 09:49:18 2022 -0700

    Extend optimization for integer bit test on __atomic_fetch_[or|and]_*

    Extend optimization for

    _1 = __atomic_fetch_or_4 (ptr_6, 0x80000000, _3);
    _5 = (signed int) _1;
    _4 = _5 >= 0;

    to

    _1 = __atomic_fetch_or_4 (ptr_6, 0x80000000, _3);
    _5 = (signed int) _1;
    if (_5 >= 0)

    gcc/

            PR middle-end/102566
            * tree-ssa-ccp.cc (optimize_atomic_bit_test_and): Also handle
            if (_5 < 0) and if (_5 >= 0).

    gcc/testsuite/

            PR middle-end/102566
            * g++.target/i386/pr102566-7.C