public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "ubizjak at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug inline-asm/52813] %rsp in clobber list is silently ignored
Date: Sun, 01 Apr 2012 18:58:00 -0000 [thread overview]
Message-ID: <bug-52813-4-blqoJna6Do@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-52813-4@http.gcc.gnu.org/bugzilla/>
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52813
--- Comment #3 from Uros Bizjak <ubizjak at gmail dot com> 2012-04-01 18:58:27 UTC ---
(In reply to comment #2)
> I don't expect the compiler to analyze the asm string. I expect the compiler
> to respect my clobber list.
>
> I told GCC that I would clobber %rsp. Any other register that I put in the
> clobber list causes GCC to save that register to the stack or to another
> register before the asm and restore it from the stack/register after the asm.
> For example:
%rsp is considered a "fixed" register, used for fixed purposes all throughout
the compiled code and are therefore not available for general allocation.
So, save %rsp at the beginning of your asm code and restore it at the end.
next prev parent reply other threads:[~2012-04-01 18:58 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-03-31 22:53 [Bug inline-asm/52813] New: " jhaberman at gmail dot com
2012-04-01 9:21 ` [Bug inline-asm/52813] " ubizjak at gmail dot com
2012-04-01 15:54 ` jhaberman at gmail dot com
2012-04-01 18:58 ` ubizjak at gmail dot com [this message]
2012-04-01 19:23 ` jhaberman at gmail dot com
2012-05-28 23:10 ` ralph-gccbugzilla at inputplus dot co.uk
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-52813-4-blqoJna6Do@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).