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Date: Mon, 15 Feb 2010 21:28:54 +0100
From: Pavel Machek <pavel@ucw.cz>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: register long sp asm("r1") incorrect
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On Tue 2010-02-16 06:59:52, Benjamin Herrenschmidt wrote:
> On Mon, 2010-02-15 at 08:34 +0100, Pavel Machek wrote:
> > > On Tue, 2010-02-09 at 16:24 +0100, Pavel Machek wrote:
> > > > ...according to gcc docs, sp should be global, or placement in
> > > > register is not guaranteed (except at asm boundaries, but there
> > are
> > > > none).
> > > 
> > > Sorry I'm not sure I grok what you mean.
> > 
> > Well, according to gcc doscs and my experience, local "register int
> > __asm()" variables only work by accident (or not at all). 
> 
> Hrm... we definitely rely on that for our thread_info() access, and so
> far it has worked well for us, but I'll poke our gcc folks just in case.

Thanks, and let me know about any results.
									Pavel
-- 
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