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From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] [PATCH 0/2] simplify global register save/restore
Date: Mon, 1 Mar 2010 14:02:00 +0000
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To: qemu-devel@nongnu.org
Cc: Paolo Bonzini <pbonzini@redhat.com>

> On 02/26/2010 07:32 PM, Paul Brook wrote:
> >> >  You could still use them for local register variables, but I can
> >> > prepare a patch to remove them (unless you do that yourself).
> >
> > I'm not sure what you mean by a "local register variable".
> 
> I'm thinking of using
> 
>    register blah blah asm(AREG1);

> as a local variable to work around deficiencies in GCC's register
> allocator.  I've seen that elsewhere though not in QEMU.

This probably doesn't do what you (or others) think it does. Local register 
variables are only honoured when used as operands to asm statements. This 
implies you already have cpu specific code, so there's no point generalising.
 
> If you prefer to remove everything, fine.

I would prefer they are removed.

Paul