public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "crazylht at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/103771] [12 Regression] Missed vectorization under -mavx512f -mavx512vl after r12-5489
Date: Tue, 18 Jan 2022 08:36:11 +0000 [thread overview]
Message-ID: <bug-103771-4-fzRRoiOU9W@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-103771-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103771
--- Comment #22 from Hongtao.liu <crazylht at gmail dot com> ---
(In reply to Hongtao.liu from comment #21)
> (In reply to Hongtao.liu from comment #20)
> > (In reply to Richard Biener from comment #19)
> > > Ah, so the issue is missing -mavx512bw which means we end up with a AVX2
> > > style
> > > mask for V32QImode. With -mavx512bw the code vectorizes fine.
> >
> > Vectorization code is worse than before, now we need to pack vectorized mask
> > which takes extra 3 instructions.
>
> Current ifcvt convert
>
> ---------dump of .ch_vect-------
> if (x.1_14 > 255)
> goto <bb 4>; [50.00%]
> else
> goto <bb 5>; [50.00%]
>
> <bb 4> [local count: 477815112]:
> _17 = -_5;
> _18 = _17 >> 31;
> iftmp.0_19 = (unsigned char) _18;
> goto <bb 6>; [100.00%]
>
> <bb 5> [local count: 477815112]:
> iftmp.0_20 = (unsigned char) _5;
>
> <bb 6> [local count: 955630225]:
> # iftmp.0_21 = PHI <iftmp.0_19(4), iftmp.0_20(5)>
> -------dump end---------
>
>
> to
> ---- dump of .ifcvt---------
> _41 = -x.1_14;
> _17 = (int) _41;
> _18 = _17 >> 31;
> iftmp.0_19 = (unsigned char) _18; -- vec_pack_trunc
> iftmp.0_20 = (unsigned char) _5; -- vec_pack_trunc
> iftmp.0_21 = x.1_14 > 255 ? iftmp.0_19 : iftmp.0_20; -- vec_pack_trunc
> *_6 = iftmp.0_21;
> x_16 = x_24 + 1;
> -----dump end----------
>
>
> if ifcvt output things like
> ------------optimal .ifcvt------
> _41 = -x.1_14;
> _17 = (int) _41;
> _18 = _17 >> 31;
> iftmp.0_21 = x.1_14 > 255 ? _18 : _5;
> iftmp.0_22 = (unsigned char) iftmp.0_21; --- vec_pack_trunc
> *_6 = iftmp.0_22;
> x_16 = x_24 + 1;
> ------------end------------
>
> we can save operations for packing mask(3 vec_pack_trunc vs 1
> vec_pack_trunc?).
Or maybe a gimple simplification for it?
next prev parent reply other threads:[~2022-01-18 8:36 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-12-20 8:59 [Bug target/103771] New: " wwwhhhyyy333 at gmail dot com
2021-12-20 11:45 ` [Bug target/103771] [12 Regression] " pinskia at gcc dot gnu.org
2022-01-04 15:31 ` tnfchris at gcc dot gnu.org
2022-01-05 9:00 ` crazylht at gmail dot com
2022-01-13 8:43 ` crazylht at gmail dot com
2022-01-13 9:02 ` crazylht at gmail dot com
2022-01-13 9:04 ` crazylht at gmail dot com
2022-01-13 9:28 ` rguenth at gcc dot gnu.org
2022-01-13 9:50 ` rguenth at gcc dot gnu.org
2022-01-13 10:04 ` crazylht at gmail dot com
2022-01-13 10:11 ` rsandifo at gcc dot gnu.org
2022-01-13 10:22 ` crazylht at gmail dot com
2022-01-13 10:43 ` crazylht at gmail dot com
2022-01-13 10:44 ` rguenther at suse dot de
2022-01-13 10:49 ` rguenther at suse dot de
2022-01-13 10:50 ` crazylht at gmail dot com
2022-01-13 12:40 ` crazylht at gmail dot com
2022-01-13 13:42 ` rguenther at suse dot de
2022-01-13 14:42 ` crazylht at gmail dot com
2022-01-14 9:40 ` rsandifo at gcc dot gnu.org
2022-01-14 10:18 ` rguenth at gcc dot gnu.org
2022-01-17 8:22 ` crazylht at gmail dot com
2022-01-18 8:31 ` crazylht at gmail dot com
2022-01-18 8:36 ` crazylht at gmail dot com [this message]
2022-01-18 10:44 ` rguenther at suse dot de
2022-01-18 10:49 ` pinskia at gcc dot gnu.org
2022-01-19 6:03 ` crazylht at gmail dot com
2022-01-19 6:10 ` pinskia at gcc dot gnu.org
2022-01-19 6:25 ` crazylht at gmail dot com
2022-01-19 7:44 ` rguenth at gcc dot gnu.org
2022-01-19 8:33 ` crazylht at gmail dot com
2022-01-19 8:48 ` rguenther at suse dot de
2022-01-20 8:52 ` cvs-commit at gcc dot gnu.org
2022-01-27 6:03 ` crazylht at gmail dot com
2022-02-01 5:21 ` pinskia at gcc dot gnu.org
2022-02-01 16:13 ` law at gcc dot gnu.org
2022-02-01 16:18 ` pinskia at gcc dot gnu.org
2022-02-13 9:58 ` cvs-commit at gcc dot gnu.org
2022-02-14 7:36 ` rguenth at gcc dot gnu.org
2022-02-14 7:45 ` crazylht at gmail dot com
2022-02-14 7:53 ` rguenth at gcc dot gnu.org
2022-02-17 11:01 ` cvs-commit at gcc dot gnu.org
2023-04-26 6:55 ` [Bug target/103771] [12/13/14 " rguenth at gcc dot gnu.org
2023-05-06 23:21 ` pinskia at gcc dot gnu.org
2023-05-08 7:38 ` cvs-commit at gcc dot gnu.org
2023-05-08 7:39 ` pinskia at gcc dot gnu.org
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-103771-4-fzRRoiOU9W@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).