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From: "redi 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 17:40:44 +0000 [thread overview] Message-ID: <bug-103066-4-kPd74BAcLZ@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 --- Comment #9 from Jonathan Wakely <redi at gcc dot gnu.org> --- I don't know what the assembly code does sorry, but it's not permitted to store to the 'expected' value unless the atomic variable is not equal to it. It looks like this would update the 'expected' value unconditionally? I agree with Jakub that we don't want the additional instructions because they will be redundant in some cases where the user has already done a load.
next prev parent reply other threads:[~2021-11-05 17:40 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 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 [this message] 2021-11-06 16:31 ` thiago at kde dot org
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