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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 target/51954] __int128_t (and long long on x86) negation can be optimized
Date: Fri, 29 Apr 2022 11:31:23 +0000	[thread overview]
Message-ID: <bug-51954-4-RWjE1VehIA@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-51954-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=51954

--- Comment #8 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Uros Bizjak <uros@gcc.gnu.org>:

https://gcc.gnu.org/g:59119253b3133b30114194a04171f9d353b5c7f7

commit r13-38-g59119253b3133b30114194a04171f9d353b5c7f7
Author: Uros Bizjak <ubizjak@gmail.com>
Date:   Fri Apr 29 13:27:48 2022 +0200

    i386: Optimize double-word negation [PR51954]

    Introduce peephole2 pattern to convert from:

       mov %esi, %edx
       negl %eax
       adcl $0, %edx
       negl %edx
     to:
       xorl %edx, %edx
       negl %eax
       sbbl %esi, %edx

    This conversion is profitable only when initial move is found.  Otherwise,
    additional move to a temporary together with clearing xor is needed.

    2022-04-29  Uroš Bizjak  <ubizjak@gmail.com>

    gcc/ChangeLog:

            PR target/51954
            * config/i386/i386.md (adcl/neg -> sbb peephole): New peephole2.
    gcc/testsuite/ChangeLog:

            PR target/51954
            * gcc.target/i386/pr51954.c: New test.

  parent reply	other threads:[~2022-04-29 11:31 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-01-23  1:43 [Bug rtl-optimization/51954] New: __int128_t " svfuerst at gmail dot com
2012-01-23  4:00 ` [Bug rtl-optimization/51954] __int128_t (and long long on x86) " pinskia at gcc dot gnu.org
2021-12-26 22:34 ` [Bug target/51954] " pinskia at gcc dot gnu.org
2022-02-21  5:57 ` pinskia at gcc dot gnu.org
2022-02-21  6:29 ` crazylht at gmail dot com
2022-02-21  6:49 ` crazylht at gmail dot com
2022-02-21  7:45 ` ubizjak at gmail dot com
2022-02-21  7:52 ` ubizjak at gmail dot com
2022-02-21  7:57 ` ubizjak at gmail dot com
2022-04-29 11:31 ` cvs-commit at gcc dot gnu.org [this message]
2022-04-29 11:33 ` ubizjak at gmail dot com

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