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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/108997] GCC prediction on bool comparisons seems wrong
Date: Fri, 03 Mar 2023 00:10:38 +0000	[thread overview]
Message-ID: <bug-108997-4-Dg2RszY6Hw@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-108997-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108997

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Nikita Kniazev from comment #3)
> For cond == 789
>   if (cond_2(D) == 789)
>     goto <bb 3>; [20.24%]
>   else
>     goto <bb 4>; [79.76%]
> 
> For cond != 789
>   if (cond_2(D) != 789)
>     goto <bb 3>; [48.88%]
>   else
>     goto <bb 4>; [51.12%]

an intergal type equaling a specific # is handled this way on purpose. Bool
should be handled differently because it only has two values, 0/1.
Anyways != is not handled specially except for the zero value case ...

  parent reply	other threads:[~2023-03-03  0:10 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-02 22:51 [Bug tree-optimization/108997] New: " pinskia at gcc dot gnu.org
2023-03-02 23:26 ` [Bug tree-optimization/108997] " nok.raven at gmail dot com
2023-03-02 23:35 ` pinskia at gcc dot gnu.org
2023-03-03  0:05 ` nok.raven at gmail dot com
2023-03-03  0:10 ` pinskia at gcc dot gnu.org [this message]
2023-03-03  8:43 ` rguenth at gcc dot gnu.org
2023-03-07 14:49 ` marxin at gcc dot gnu.org

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