From: Momchil Velikov <velco@fadata.bg>
To: linux-kernel@vger.kernel.org
Cc: gcc@gcc.gnu.org
Subject: i386 flags register clober in inline assembly
Date: 17 Nov 2001 16:06:22 +0200 [thread overview]
Message-ID: <87y9l58pb5.fsf@fadata.bg> (raw)
There are several inline assembly routines in the i386 port, which
clobber the flags register, nevertheless fail to declare that.
E.g. atomic_inc
__asm__ __volatile__(
LOCK "incl %0"
:"=m" (v->counter)
:"m" (v->counter));
should be
__asm__ __volatile__(
LOCK "incl %0"
:"=m" (v->counter)
:"m" (v->counter)
: "cc");
since "incl" clobbers flags.
Any ideas if these functions should be corrected ?
Although gcc documentation says "cc" has no effect on some machines,
it seems this is not the case with i386, judging from the "(set (reg:CC 17) ..."
and "(clobber (reg:CC 17))" in i386.md.
Regards,
-velco
next reply other threads:[~2001-11-17 14:09 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2001-11-17 14:06 Momchil Velikov [this message]
2001-11-17 15:14 ` i386 flags register clober in inline assembly Jan Hubicka
2001-11-17 19:20 ` Linus Torvalds
2001-11-17 19:58 ` H. Peter Anvin
2001-11-17 20:24 ` Momchil Velikov
2001-11-17 20:30 ` Linus Torvalds
2001-11-17 20:40 ` Jan Hubicka
2001-11-17 20:42 ` Linus Torvalds
2001-11-18 1:09 ` Jan Hubicka
2001-11-18 2:48 ` Linus Torvalds
2001-11-20 8:33 ` Richard Henderson
2001-11-20 13:00 ` Jan Hubicka
2001-11-20 23:14 ` Richard Henderson
2001-11-20 17:12 ` Linus Torvalds
2001-11-17 21:00 ` H. Peter Anvin
2001-11-20 14:39 ` PATCH 2.4.15-pre6 idt compilation and proc_misc cleanup Martin Dalecki
2001-11-23 22:24 ` Roman Zippel
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=87y9l58pb5.fsf@fadata.bg \
--to=velco@fadata.bg \
--cc=gcc@gcc.gnu.org \
--cc=linux-kernel@vger.kernel.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