mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: "D. Jeff Dionne" <djeffdionne@gmail.com>
To: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>,
	Yoshinori Sato <ysato@users.sourceforge.jp>,
	Rich Felker <dalias@libc.org>,
	Palmer Dabbelt <palmer@rivosinc.com>,
	Linux-sh list <linux-sh@vger.kernel.org>,
	linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3] sh: Use generic GCC library routines
Date: Fri, 21 Apr 2023 20:16:06 +0900	[thread overview]
Message-ID: <E21A1070-ABD7-4D33-90BF-AB44E584AE7F@gmail.com> (raw)
In-Reply-To: <434fe02c2c774ae4d1694ff222884bc5d5fc25e6.camel@physik.fu-berlin.de>



> On Apr 21, 2023, at 20:03, John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> wrote:
> 
> Hi Geert!
> 
> On Thu, 2023-03-23 at 11:18 +0100, Geert Uytterhoeven wrote:
>> The C implementations of __ashldi3(), __ashrdi3__(), and __lshrdi3() in
>> arch/sh/lib/ are identical to the generic C implementations in lib/.
>> Reduce duplication by switching SH to the generic versions.
...
> 
> Why are the single-precision (denoted as "si") variants not being replaced?
> 
> Don't we have generic versions for these?

The SH arch versions of si variants are optimized assembler, which is pretty important… these are things like bit shifts.

Actually, it would be better to have the di variants be hand coded asm also… I’m not sure how much use the kernel makes of those, and I’ve not looked if there is a good source of optimized SH versions those with the right license.

J.

> 
> Adrian
> 
> -- 
> .''`.  John Paul Adrian Glaubitz
> : :' :  Debian Developer
> `. `'   Physicist
>  `-    GPG: 62FF 8A75 84E0 2956 9546  0006 7426 3B37 F5B5 F913


  reply	other threads:[~2023-04-21 11:16 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-23 10:18 Geert Uytterhoeven
2023-03-27 14:26 ` kernel test robot
2023-04-21 11:03 ` John Paul Adrian Glaubitz
2023-04-21 11:16   ` D. Jeff Dionne [this message]
2023-04-21 12:14   ` Geert Uytterhoeven
2023-04-24  7:45 ` John Paul Adrian Glaubitz

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=E21A1070-ABD7-4D33-90BF-AB44E584AE7F@gmail.com \
    --to=djeffdionne@gmail.com \
    --cc=dalias@libc.org \
    --cc=geert+renesas@glider.be \
    --cc=glaubitz@physik.fu-berlin.de \
    --cc=linux-kbuild@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-sh@vger.kernel.org \
    --cc=palmer@rivosinc.com \
    --cc=ysato@users.sourceforge.jp \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®