public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/66502] SCCVN can't handle PHIs optimistically optimally
Date: Thu, 11 Jun 2015 09:19:00 -0000 [thread overview]
Message-ID: <bug-66502-4-o4j0kOG71s@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-66502-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66502
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |ASSIGNED
Last reconfirmed| |2015-06-11
Assignee|unassigned at gcc dot gnu.org |rguenth at gcc dot gnu.org
Ever confirmed|0 |1
--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
https://gcc.gnu.org/ml/gcc-patches/2015-06/msg00760.html was posted that
changes the current preference to handle the first testcase (but no longer
the second). The first opportunity is frequently introduced by the vectorizer,
together with redundant loads, that are not eliminated in any way currently.
IVOPTs can remove redundant IVs but the issue is usually that it can't prove
the initial values are the same nor does it remove the redundant loads
leading to cost model issues (DOM might later remove the redundant loads).
The above mentioned patch passed bootstrap & regtest on
x86_64-unknown-linux-gnu.
Enlarging the SCCs to cover all candidates is a bit tricky in the current
framework, I still like to experiment with that idea.
next parent reply other threads:[~2015-06-11 9:19 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <bug-66502-4@http.gcc.gnu.org/bugzilla/>
2015-06-11 9:19 ` rguenth at gcc dot gnu.org [this message]
2015-08-13 7:06 ` rguenth at gcc dot gnu.org
2015-08-13 7:11 ` rguenth at gcc dot gnu.org
2021-12-13 8:31 ` pinskia at gcc dot gnu.org
2022-01-03 9:50 ` rguenth at gcc dot gnu.org
2022-01-03 9:50 ` cvs-commit at gcc dot gnu.org
2022-01-07 6:38 ` 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-66502-4-o4j0kOG71s@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).