From: Segher Boessenkool <segher@kernel.crashing.org>
To: Nicholas Piggin <npiggin@gmail.com>
Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] powerpc/irq: Modernise inline assembly in irq_soft_mask_{set,return}
Date: Sat, 24 Sep 2022 13:30:50 -0500 [thread overview]
Message-ID: <20220924183050.GP25951@gate.crashing.org> (raw)
In-Reply-To: <20220923221543.GN25951@gate.crashing.org>
On Fri, Sep 23, 2022 at 05:15:43PM -0500, Segher Boessenkool wrote:
> On Sat, Sep 24, 2022 at 02:26:52AM +1000, Nicholas Piggin wrote:
> > I still don't see what clauses guarantees asm("%0" ::"r"(foo)) to give
> > 13. It doesn't say access via inline assembly is special,
>
> But it is. It is for all register variables, local and global. I agree
> this isn't documented clearly. For local register variables this is the
> *only* thing guaranteed; for global register vars there is more (it
> changes the ABI, there are safe/restore effects, that kind of thing).
I filed <https://gcc.gnu.org/PR107027> to improve the docs. Thanks for
bringing this to our attention!
Segher
prev parent reply other threads:[~2022-09-24 18:34 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-20 6:41 [PATCH] powerpc/irq: Modernise inline assembly in irq_soft_mask_{set,return} Christophe Leroy
2022-09-23 7:08 ` Nicholas Piggin
2022-09-23 12:18 ` Segher Boessenkool
2022-09-23 16:26 ` Nicholas Piggin
2022-09-23 22:15 ` Segher Boessenkool
2022-09-24 4:00 ` Nicholas Piggin
2022-09-24 16:14 ` Segher Boessenkool
2022-09-24 18:30 ` Segher Boessenkool [this message]
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=20220924183050.GP25951@gate.crashing.org \
--to=segher@kernel.crashing.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=npiggin@gmail.com \
/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