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/98442] [X86] suboptimal for memset with CLEAR_BY_PIECES
Date: Thu, 31 Dec 2020 03:38:54 +0000	[thread overview]
Message-ID: <bug-98442-4-hC29S1od3s@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-98442-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98442

--- Comment #1 from Hongtao.liu <crazylht at gmail dot com> ---
> 
> Define TARGET_USE_BY_PIECES_INFRASTRUCTURE_P for i386?

It's actually determined by MOV_MAX_PIECES and related to MAX_FIXED_MODE_SIZE

   ??? We should use TImode in 32-bit mode and use OImode or XImode
   if they are available.  But since by_pieces_ninsns determines the
   widest mode with MAX_FIXED_MODE_SIZE, we can only use TImode in
   64-bit mode.  */
#define MOVE_MAX_PIECES \
  ((TARGET_64BIT \
    && TARGET_SSE2 \
    && TARGET_SSE_UNALIGNED_LOAD_OPTIMAL \
    && TARGET_SSE_UNALIGNED_STORE_OPTIMAL) \
   ? GET_MODE_SIZE (OImode) : UNITS_PER_WORD)

  reply	other threads:[~2020-12-31  3:38 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-12-25  1:38 [Bug target/98442] New: " crazylht at gmail dot com
2020-12-31  3:38 ` crazylht at gmail dot com [this message]
2020-12-31  3:48 ` [Bug target/98442] " hjl.tools at gmail dot com
2020-12-31  3:56 ` hjl.tools at gmail dot com
2021-01-05 10:05 ` rguenth at gcc dot gnu.org
2021-10-06 23:48 ` hjl.tools 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-98442-4-hC29S1od3s@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).