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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/103066] __sync_val_compare_and_swap/__sync_bool_compare_and_swap aren't optimized
Date: Fri, 05 Nov 2021 12:17:00 +0000	[thread overview]
Message-ID: <bug-103066-4-uAXTF6WrBj@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-103066-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103066

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
If by fail you mean that it doesn't update the memory if the memory isn't equal
to expected, sure, but do you mean it can fail spuriously, not update the
memory even if the memory is equal to expected?
Neither __sync_{bool,val}_compare_and_swap nor __atomic_compare_exchange_n with
weak set to false can fail spuriously, __atomic_compare_exchange_n with weak
set to true can.

  parent reply	other threads:[~2021-11-05 12:17 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-11-03 17:35 [Bug target/103066] New: " hjl.tools at gmail dot com
2021-11-05  5:57 ` [Bug target/103066] " wwwhhhyyy333 at gmail dot com
2021-11-05 11:57 ` hjl.tools at gmail dot com
2021-11-05 12:17 ` jakub at gcc dot gnu.org [this message]
2021-11-05 12:33 ` hjl.tools at gmail dot com
2021-11-05 12:44 ` jakub at gcc dot gnu.org
2021-11-05 12:55 ` jakub at gcc dot gnu.org
2021-11-05 13:07 ` hjl.tools at gmail dot com
2021-11-05 13:25 ` jakub at gcc dot gnu.org
2021-11-05 17:40 ` redi at gcc dot gnu.org
2021-11-06 16:31 ` thiago at kde dot org

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