public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "rguenther at suse dot de" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/103554] -mavx generates worse code on scalar code
Date: Mon, 06 Dec 2021 11:52:08 +0000 [thread overview]
Message-ID: <bug-103554-4-HOPJuPeczz@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-103554-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103554
--- Comment #6 from rguenther at suse dot de <rguenther at suse dot de> ---
On Mon, 6 Dec 2021, avi at scylladb dot com wrote:
> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103554
>
> --- Comment #5 from Avi Kivity <avi at scylladb dot com> ---
> Here's some big-picture data. Compiled with clang, which seems to ignore these
> STLF issues.
>
> no-slp:
>
> 42641.91 tps ( 75.1 allocs/op, 12.1 tasks/op, 44929 insns/op)
> 42446.41 tps ( 75.1 allocs/op, 12.1 tasks/op, 44870 insns/op)
> 42495.03 tps ( 75.1 allocs/op, 12.1 tasks/op, 44931 insns/op)
> 42703.40 tps ( 75.1 allocs/op, 12.1 tasks/op, 44916 insns/op)
> 42798.98 tps ( 75.1 allocs/op, 12.1 tasks/op, 44963 insns/op)
>
> slp:
>
> 41536.46 tps ( 75.1 allocs/op, 12.1 tasks/op, 44828 insns/op)
> 41482.05 tps ( 75.1 allocs/op, 12.1 tasks/op, 44802 insns/op)
> 41707.23 tps ( 75.1 allocs/op, 12.1 tasks/op, 44874 insns/op)
> 41811.10 tps ( 75.1 allocs/op, 12.1 tasks/op, 44847 insns/op)
> 41764.39 tps ( 75.1 allocs/op, 12.1 tasks/op, 44846 insns/op)
>
> So slp definitely has negative impact on ops/sec, even though it reduces
> instructions/op. This is on an older machine (newer ones have ~5X perf, with 3X
> higher IPC and the rest due to higher frequency).
Is that with the function inlined? Can you show the argument setup
code at the caller side?
next prev parent reply other threads:[~2021-12-06 11:52 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-12-04 15:37 [Bug target/103554] New: " avi at scylladb dot com
2021-12-04 22:08 ` [Bug target/103554] " pinskia at gcc dot gnu.org
2021-12-06 8:36 ` rguenth at gcc dot gnu.org
2021-12-06 9:00 ` avi at scylladb dot com
2021-12-06 11:00 ` rguenther at suse dot de
2021-12-06 11:23 ` avi at scylladb dot com
2021-12-06 11:52 ` rguenther at suse dot de [this message]
2021-12-06 11:59 ` avi at scylladb dot com
2021-12-07 2:26 ` crazylht at gmail dot com
2021-12-07 8:36 ` rguenth at gcc dot gnu.org
2021-12-07 9:51 ` crazylht at gmail dot com
2021-12-07 10:28 ` rguenther at suse dot de
2021-12-09 3:07 ` crazylht at gmail dot com
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=bug-103554-4-HOPJuPeczz@http.gcc.gnu.org/bugzilla/ \
--to=gcc-bugzilla@gcc.gnu.org \
--cc=gcc-bugs@gcc.gnu.org \
/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;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).