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From: "hjl.tools at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/103069] cmpxchg isn't optimized
Date: Mon, 24 Jan 2022 23:53:57 +0000	[thread overview]
Message-ID: <bug-103069-4-qjE4A8yKhI@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 #8 from H.J. Lu <hjl.tools at gmail dot com> ---
nptl/pthread_create.c has

              do
                pd->nextevent = __nptl_last_event;
              while (atomic_compare_and_exchange_bool_acq (&__nptl_last_event,
                                                           pd, pd->nextevent));

we got

         8d1b7: 48 8b 05 da 55 16 00    mov    0x1655da(%rip),%rax        
         8d1be: 48 89 83 68 06 00 00    mov    %rax,0x668(%rbx)
         8d1c5: f0 4c 0f b1 35 ca 55    lock cmpxchg %r14,0x1655ca(%rip)        

         8d1ce: 75 e7                   jne    8d1b7
<pthread_create@@GLIBC_2.34
+0xb57>

  parent reply	other threads:[~2022-01-24 23:53 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 [this message]
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
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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