All of lore.kernel.org
 help / color / mirror / Atom feed
From: Segher Boessenkool <segher@kernel.crashing.org>
To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Boqun Feng <boqun.feng@gmail.com>,
	linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
	Michael Jeanson <mjeanson@efficios.com>
Subject: Re: Failure to build librseq on ppc
Date: Wed, 8 Jul 2020 19:18:37 -0500	[thread overview]
Message-ID: <20200709001837.GD3598@gate.crashing.org> (raw)
In-Reply-To: <1968953502.5815.1594252883512.JavaMail.zimbra@efficios.com>

On Wed, Jul 08, 2020 at 08:01:23PM -0400, Mathieu Desnoyers wrote:
> > > #define RSEQ_ASM_OP_CMPEQ(var, expect, label)                                   \
> > >                 LOAD_WORD "%%r17, %[" __rseq_str(var) "]\n\t"                   \
> > 
> > The way this hardcodes r17 *will* break, btw.  The compiler will not
> > likely want to use r17 as long as your code (after inlining etc.!) stays
> > small, but there is Murphy's law.
> 
> r17 is in the clobber list, so it should be ok.

What protects r17 *after* this asm statement?


Segher

  reply	other threads:[~2020-07-09  0:20 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-07 19:17 Failure to build librseq on ppc Mathieu Desnoyers
2020-07-08  0:59 ` Segher Boessenkool
2020-07-08 12:27   ` Michael Ellerman
2020-07-08 23:53     ` Segher Boessenkool
2020-07-09  0:01       ` Mathieu Desnoyers
2020-07-09  0:18         ` Segher Boessenkool [this message]
2020-07-09 13:43           ` Mathieu Desnoyers
2020-07-09 17:37             ` Segher Boessenkool
2020-07-09 17:42               ` Mathieu Desnoyers
2020-07-09 17:56                 ` Mathieu Desnoyers
2020-07-09 20:46                   ` Segher Boessenkool
2020-07-09 20:57                     ` Mathieu Desnoyers
2020-07-09 20:31                 ` Segher Boessenkool
2020-07-08 12:33   ` Mathieu Desnoyers
2020-07-08 14:00     ` Mathieu Desnoyers
2020-07-08 14:21       ` Christophe Leroy
2020-07-08 14:32         ` Mathieu Desnoyers
2020-07-08 16:11           ` Christophe Leroy
2020-07-09  0:15           ` Segher Boessenkool
2020-07-09  0:10       ` Segher Boessenkool
2020-07-09 13:33         ` Mathieu Desnoyers
2020-07-09 17:31           ` Segher Boessenkool

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=20200709001837.GD3598@gate.crashing.org \
    --to=segher@kernel.crashing.org \
    --cc=boqun.feng@gmail.com \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=mathieu.desnoyers@efficios.com \
    --cc=mjeanson@efficios.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.