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From: torvalds@transmeta.com (Linus Torvalds)
Subject: Re: Using %cr2 to reference "current"
Date: Tue, 6 Nov 2001 17:04:24 +0000 (UTC)
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In article <E1613vx-00005r-00@the-village.bc.nu>,
Alan Cox  <alan@lxorguk.ukuu.org.uk> wrote:
>
>It may be. Likewise its not clear if %cr2 should hold current or a cpu ident
>pointer (so you dont reload on switch of task). This needs more
>benchmarking. Its in current -ac to verify the theory is correct not the
>tuning.

We pretty much know the _theory_ is not correct, just by virtue of
depending on non-architected behaviour.  The only thing -ac can do is
test whether it works in practice.  Which is a totally different thing. 

Especially on x86 chips.

		Linus
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