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From: "crazylht at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/102294] memset expansion is sometimes slow for small sizes
Date: Mon, 13 Sep 2021 03:28:57 +0000	[thread overview]
Message-ID: <bug-102294-4-CqOetCLlNz@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-102294-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102294

--- Comment #10 from Hongtao.liu <crazylht at gmail dot com> ---
(In reply to Bart Van Assche from comment #9)
> Hmm ... isn't movups a floating-point instruction? I want to avoid floating
> point instructions since my understanding is that it is not allowed to use
> these in kernel code. See e.g.
> https://stackoverflow.com/questions/13886338/use-of-floating-point-in-the-
> linux-kernel.

then as pinski mentioned in #c1, -mno-sse is needed, i guess for clang case,
xmm mov is also used which also shouldn't be available in kernel.

  parent reply	other threads:[~2021-09-13  3:28 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-09-12 21:59 [Bug c/102294] New: structure assignment slower than memberwise initialization bart.vanassche at gmail dot com
2021-09-12 22:17 ` [Bug middle-end/102294] " pinskia at gcc dot gnu.org
2021-09-13  1:41 ` bart.vanassche at gmail dot com
2021-09-13  1:43 ` bart.vanassche at gmail dot com
2021-09-13  1:59 ` pinskia at gcc dot gnu.org
2021-09-13  2:16 ` bart.vanassche at gmail dot com
2021-09-13  2:25 ` pinskia at gcc dot gnu.org
2021-09-13  2:57 ` [Bug middle-end/102294] memset expansion is sometimes slow for small sizes bart.vanassche at gmail dot com
2021-09-13  3:06 ` crazylht at gmail dot com
2021-09-13  3:21 ` bart.vanassche at gmail dot com
2021-09-13  3:28 ` crazylht at gmail dot com [this message]
2021-09-13  3:40 ` [Bug target/102294] " pinskia at gcc dot gnu.org
2021-09-13 13:37 ` hjl.tools at gmail dot com
2021-09-14  2:04 ` bart.vanassche at gmail dot com

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