public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "mx682x at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/110217] [avr] SREG: use BSET and BCLR instead of load/modify/write
Date: Mon, 10 Jul 2023 07:18:27 +0000 [thread overview]
Message-ID: <bug-110217-4-3TABy4TEKh@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-110217-4@http.gcc.gnu.org/bugzilla/>
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110217
--- Comment #2 from mx682x at gmail dot com ---
I see, thank you for you input.
> Apart from that, the proposed patch won't work for indirect addressing, or
> when the compiler is turning direct addresses to indirect addresses (using
> CSE etc, common subexpression elimination and similar strategies).
>
> Also the patch relies on insn combine which only runs when optimization is
> on, thus any application which relies on that optimization will glitch at
> -O0.
However, just out of curiosity, doesn't this also apply to the "Single-Cycle
I/O access" instructions cbi/sbi? Afterall, I've just duplicated the respective
code and andjusted the predicate for the address.
next prev parent reply other threads:[~2023-07-10 7:18 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-12 9:23 [Bug target/110217] New: " mx682x at gmail dot com
2023-06-30 16:53 ` [Bug target/110217] " gjl at gcc dot gnu.org
2023-07-10 7:18 ` mx682x at gmail dot com [this message]
2023-07-12 9:23 ` gjl at gcc dot gnu.org
2023-07-12 20:01 ` gjl 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-110217-4-3TABy4TEKh@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).