From: Russell King - ARM Linux <linux@arm.linux.org.uk>
To: Saravana Kannan <skannan@codeaurora.org>
Cc: Will Deacon <will.deacon@arm.com>,
linux-arm-msm@vger.kernel.org,
David Brown <davidb@codeaurora.org>,
Stephen Boyd <sboyd@codeaurora.org>,
linux-kernel@vger.kernel.org,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH 2/4] msm: scm: Fix improper register assignment
Date: Sat, 26 Feb 2011 08:47:36 +0000 [thread overview]
Message-ID: <20110226084736.GB3640@n2100.arm.linux.org.uk> (raw)
In-Reply-To: <4D688AF1.1090607@codeaurora.org>
On Fri, Feb 25, 2011 at 09:09:05PM -0800, Saravana Kannan wrote:
> Yeah, Stephen and I spent quite a bit of time discussing this and
> experimenting to figure out what the heck GCC was doing. But it kept
> optimizing the fake code we put in trying to force GCC to use a specific
> register.
One way to look at it is that if you specify a value for r0, assign it,
and then call a function, how do you expect the r0 value to be preserved?
r0 will be corrupted by the called function as its used to pass arg0 and
the return value.
I'm surprised the compiler didn't spit out an error.
next prev parent reply other threads:[~2011-02-26 8:48 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-02-24 18:44 [PATCH 0/4] SCM fixes and updates Stephen Boyd
2011-02-24 18:44 ` [PATCH 1/4] msm: scm: Mark inline asm as volatile Stephen Boyd
2011-02-25 11:56 ` Will Deacon
2011-02-25 19:05 ` Stephen Boyd
2011-02-26 18:12 ` David Brown
2011-02-26 19:43 ` Nicolas Pitre
2011-02-27 17:41 ` David Brown
2011-02-28 2:21 ` Nicolas Pitre
2011-02-27 11:10 ` Will Deacon
2011-02-27 17:38 ` David Brown
2011-03-01 10:30 ` Will Deacon
2011-02-24 18:44 ` [PATCH 2/4] msm: scm: Fix improper register assignment Stephen Boyd
2011-02-25 13:23 ` Will Deacon
2011-02-25 19:22 ` Stephen Boyd
2011-02-26 5:09 ` Saravana Kannan
2011-02-26 8:47 ` Russell King - ARM Linux [this message]
2011-02-26 17:58 ` David Brown
2011-02-26 20:04 ` Nicolas Pitre
2011-03-01 10:37 ` Will Deacon
2011-03-01 21:29 ` Saravana Kannan
2011-03-02 0:02 ` Nicolas Pitre
2011-03-01 13:54 ` Will Deacon
2011-02-24 18:44 ` [PATCH 3/4] msm: scm: Check for interruption immediately Stephen Boyd
2011-02-24 18:44 ` [PATCH 4/4] msm: scm: Get cacheline size from CTR Stephen Boyd
2011-02-24 19:01 ` Thomas Gleixner
2011-02-24 19:44 ` Stephen Boyd
2011-02-24 19:56 ` Thomas Gleixner
2011-03-01 4:21 ` Stephen Boyd
2011-02-24 19:32 ` Sergei Shtylyov
2011-02-24 19:50 ` Stephen Boyd
2011-02-24 19:55 ` Russell King - ARM Linux
2011-03-09 19:29 ` [PATCH 0/4] SCM fixes and updates Stephen Boyd
2011-03-10 20:06 ` David Brown
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=20110226084736.GB3640@n2100.arm.linux.org.uk \
--to=linux@arm.linux.org.uk \
--cc=davidb@codeaurora.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=sboyd@codeaurora.org \
--cc=skannan@codeaurora.org \
--cc=will.deacon@arm.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;
as well as URLs for NNTP newsgroup(s).