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From: "wwwhhhyyy333 at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/103069] cmpxchg isn't optimized
Date: Tue, 22 Feb 2022 08:21:00 +0000	[thread overview]
Message-ID: <bug-103069-4-dIyNB4r1LT@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-103069-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103069

--- Comment #15 from Hongyu Wang <wwwhhhyyy333 at gmail dot com> ---
(In reply to Thiago Macieira from comment #14)
> I'd restrict relaxations to loops emitted by the compiler. All other atomic
> operations shouldn't be modified at all, unless the user asks for it. That
> includes non-looping atomic operations (like LOCK BTC, LOCK XADD) as well as
> a pure LOCK CMPXCHG that came from a single __atomic_compare_exchange by the
> user.
> 
> I'd welcome the ability to relax the latter, especially if with one codebase
> I could be efficient in CAS architectures as well as LL/SC ones.

The latest patch relaxed the pure LOCK CMPXCHG with -mrelax-cmpxchg-loop as the
commit message shows. So if you want, I can split this part to another switch
like -mrelax-cmpxchg-insn.

  parent reply	other threads:[~2022-02-22  8:21 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-11-03 19:08 [Bug target/103069] New: " hjl.tools at gmail dot com
2021-11-03 20:53 ` [Bug target/103069] " thiago at kde dot org
2021-11-04 21:25 ` thiago at kde dot org
2021-11-15 11:10 ` cvs-commit at gcc dot gnu.org
2021-11-15 14:26 ` hjl.tools at gmail dot com
2021-11-18  8:31 ` cvs-commit at gcc dot gnu.org
2022-01-24 23:49 ` hjl.tools at gmail dot com
2022-01-24 23:52 ` hjl.tools at gmail dot com
2022-01-24 23:53 ` hjl.tools at gmail dot com
2022-01-24 23:55 ` hjl.tools at gmail dot com
2022-01-25  0:04 ` thiago at kde dot org
2022-02-15  8:59 ` wwwhhhyyy333 at gmail dot com
2022-02-22  3:36 ` cvs-commit at gcc dot gnu.org
2022-02-22  3:38 ` wwwhhhyyy333 at gmail dot com
2022-02-22  4:16 ` thiago at kde dot org
2022-02-22  8:21 ` wwwhhhyyy333 at gmail dot com [this message]
2022-02-22 18:05 ` thiago at kde dot org
2022-02-22 18:41 ` jakub at gcc dot gnu.org
2022-02-22 20:25 ` thiago at kde dot org
2022-02-23  3:35 ` wwwhhhyyy333 at gmail dot com
2022-02-23  4:06 ` thiago at kde dot org
2022-04-13  8:18 ` cvs-commit at gcc dot gnu.org
2022-05-06  8:31 ` jakub at gcc dot gnu.org
2023-05-08 12:23 ` rguenth at gcc dot gnu.org

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