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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/110007] Implement support for Clang’s __builtin_unpredictable()
Date: Sat, 27 May 2023 18:01:33 +0000 [thread overview]
Message-ID: <bug-110007-4-Ht5SQpS1yn@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-110007-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110007
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Richard Yao from comment #0)
> Having the ability to specify __builtin_unpredictable() as a hint to
> encourage the compiler to use cmov would be useful for implementing
> algorithms like binary search that have unpredictable branches.
> __builtin_expect_with_probability() looks like a possible substitute, but
> Clang does not support it and it does not always work as described in
> #110001.
PR 110001 has nothing to do with __builtin_expect_with_probability and
__builtin_expect_with_probability will do exactly the same as
__builtin_unpredictable will do really.
next prev parent reply other threads:[~2023-05-27 18:01 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-05-27 17:54 [Bug c/110007] New: " richard.yao at alumni dot stonybrook.edu
2023-05-27 17:59 ` [Bug c/110007] " pinskia at gcc dot gnu.org
2023-05-27 18:01 ` pinskia at gcc dot gnu.org [this message]
2023-05-27 18:19 ` richard.yao at alumni dot stonybrook.edu
2023-05-27 18:25 ` pinskia at gcc dot gnu.org
2023-05-27 20:26 ` richard.yao at alumni dot stonybrook.edu
2023-05-28 5:42 ` amonakov at gcc dot gnu.org
2023-05-28 16:21 ` hubicka at gcc dot gnu.org
2023-05-28 21:37 ` richard.yao at alumni dot stonybrook.edu
2023-05-30 7:49 ` rguenth at gcc dot gnu.org
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