From: Jakub Jelinek <jakub@redhat.com>
To: Richard Biener <rguenther@suse.de>
Cc: gcc-patches@gcc.gnu.org
Subject: Re: [PATCH] tree-optimization/110434 - avoid <retval> ={v} {CLOBBER} from NRV
Date: Wed, 28 Jun 2023 14:38:54 +0200 [thread overview]
Message-ID: <ZJwp3hkmgkrUiSQP@tucnak> (raw)
In-Reply-To: <nycvar.YFH.7.77.849.2306281227240.4723@jbgna.fhfr.qr>
On Wed, Jun 28, 2023 at 12:32:51PM +0000, Richard Biener wrote:
> As said there's nothing run after NRV.
There is expansion but in the <result> case I strongly doubt we are trying
to stack reuse it for other vars, so maybe it is ok.
> > On the other side, could there be partial clobbers for the var -> <result>,
> > var.fld = {CLOBBER};
> > ? Or even worse, indirect clobbers (MEM_REF with SSA_NAME pointing to
> > var or parts of it)?
>
> We know that 'var' is not address taken, not sure about the partial
> clobbers. We could deal with this in the walk_gimple_op case and
> simply remove a clobber when data.modified.
LGTM.
Jakub
next prev parent reply other threads:[~2023-06-28 12:39 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20230628102150.620743857B8E@sourceware.org>
2023-06-28 10:37 ` Jakub Jelinek
2023-06-28 12:32 ` Richard Biener
2023-06-28 12:38 ` Jakub Jelinek [this message]
[not found] <20230628102159.84C093858412@sourceware.org>
2023-06-28 14:19 ` Jeff Law
2023-06-28 10:21 Richard Biener
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=ZJwp3hkmgkrUiSQP@tucnak \
--to=jakub@redhat.com \
--cc=gcc-patches@gcc.gnu.org \
--cc=rguenther@suse.de \
/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).