public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/107833] [12/13 Regression] wrong code at -Os and above on x86_64-linux-gnu since r12-5138-ge82c382971664d6f
Date: Fri, 02 Dec 2022 10:16:25 +0000	[thread overview]
Message-ID: <bug-107833-4-8voTV5QLfL@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-107833-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107833

--- Comment #12 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
So, do we whack-a-mole in this case some more and try harder in
mark_ssa_maybe_undefs
by basically repeating the CCP4 UNDEFINED propagation, or invent some new stmt
or marking that IVOPTS could use before the loop to turn possibly undefined
into undefined but always the same random pattern within the same invocation
(kind of like asm ("" : "+g" (undef));), or something else (like after IVOPTS
stop the UNDEFINED propagation on loop header PHIs or something similar)?

  parent reply	other threads:[~2022-12-02 10:16 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-11-23 12:48 [Bug tree-optimization/107833] New: wrong code at -Os and above on x86_64-linux-gnu zhendong.su at inf dot ethz.ch
2022-11-23 13:14 ` [Bug tree-optimization/107833] wrong code at -Os and above on x86_64-linux-gnu since r12-5138-ge82c382971664d6f marxin at gcc dot gnu.org
2022-11-23 14:12 ` aldyh at gcc dot gnu.org
2022-11-23 14:17 ` marxin at gcc dot gnu.org
2022-11-23 15:07 ` aldyh at gcc dot gnu.org
2022-11-23 19:22 ` marxin at gcc dot gnu.org
2022-11-23 20:56 ` [Bug tree-optimization/107833] [12/13 Regression] " rguenth at gcc dot gnu.org
2022-12-01 16:14 ` jakub at gcc dot gnu.org
2022-12-01 16:52 ` jakub at gcc dot gnu.org
2022-12-01 17:32 ` jakub at gcc dot gnu.org
2022-12-01 19:54 ` pinskia at gcc dot gnu.org
2022-12-02  8:19 ` rguenth at gcc dot gnu.org
2022-12-02 10:16 ` jakub at gcc dot gnu.org [this message]
2022-12-02 13:24 ` rguenther at suse dot de
2022-12-02 13:55 ` rguenth at gcc dot gnu.org
2022-12-05  9:32 ` cvs-commit at gcc dot gnu.org
2022-12-12 11:20 ` [Bug tree-optimization/107833] [12 " cvs-commit at gcc dot gnu.org
2022-12-12 11:22 ` rguenth 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-107833-4-8voTV5QLfL@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).