public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "vmakarov at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/113354] Regression/14: unable to find a register to spill on mips
Date: Fri, 12 Jan 2024 18:34:32 +0000	[thread overview]
Message-ID: <bug-113354-4-ocxnTJxI6s@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-113354-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113354

Vladimir Makarov <vmakarov at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |vmakarov at gcc dot gnu.org

--- Comment #2 from Vladimir Makarov <vmakarov at gcc dot gnu.org> ---
Thank you for reporting this.  The issue is not in the patch itself.  The patch
simply triggered a hidden bug.

The insn in the question looks like

1657: {r3001:SI=r291:SI*r294:SI+r3002:SI;clobber r2788:SI;clobber r2390:SI;}

On the 1st subpass we choose alternative with the following constraints

(0) l  (1) d  (2) d  (3) l  (4) X  (5) X {*mul_acc_si}

On the second subpass we choose alternative

(0) l  (1) d  (2) d  (3) l  (4) X  (5) X {*mul_acc_si}

p2788 happened to get MD0 and it prevents p3001 to get MD0 too.   p2788 can be
in any location for this alternative but LRA assignment subpass does not take
this into account.

I'll try to fix this hidden bug on the beginning of the next week.

  parent reply	other threads:[~2024-01-12 18:34 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-01-12 12:28 [Bug middle-end/113354] New: " syq at gcc dot gnu.org
2024-01-12 14:02 ` [Bug middle-end/113354] " syq at gcc dot gnu.org
2024-01-12 18:34 ` vmakarov at gcc dot gnu.org [this message]
2024-01-13  0:46 ` [Bug middle-end/113354] [14 Regression] : " pinskia at gcc dot gnu.org
2024-01-15 15:26 ` cvs-commit at gcc dot gnu.org
2024-01-17  9:44 ` syq 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-113354-4-ocxnTJxI6s@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).