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Date: Mon, 10 Sep 2007 18:16:24 +0100
From: Jamie Lokier <jamie@shareable.org>
Subject: Re: [Qemu-devel] expose host CPU features to guests: Take 2
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To: qemu-devel@nongnu.org

Dan Kenigsberg wrote:
> On Mon, Sep 10, 2007 at 12:47:51PM +0100, Natalia Portillo wrote:
> > I don't see in what is it useful without KVM/KQEMU.
> 
> It is not. I tried to be clear about it in my post. Sorry for not being
> clearer.

Some day it may be useful without KVM/KQEMU, but not for a long time.

There are instructions, for example MMX/SSE, which might be translated
efficiently to single instructions on some host CPUs but to long
function calls on others.  But that won't happen until the translation
back end is quite a lot more sophisticated than it is now.

-- Jamie