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Date: Mon, 31 May 2004 22:17:41 -0500
From: "Steven J. Hill" <sjhill@realitydiluted.com>
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To: Guido Guenther <agx@sigxcpu.org>
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Subject: Re: TLS register
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Guido Guenther wrote:
>
> He suggested $24 (t8) another discussed possibility would be $27 (k1)
> which is already abused by the PS/2 folks for ll/sc emulation.
> Another possibility would be to reserve such a register only in the
> n32/n64 ABIs and let o32 stay without __thread and TLS forever.
> Any feedback welcome.
>
I vote for $24 (t8). LL/SC emulation is an issue and I believe some of
the exception vectors, if not all of them indirectly depend on k1. It
would take a lot of work (and testing) to rewrite the exceptions to not
utilize k1 and it would probably be a nasty performance hit in many
cases. I agree with "Screw o32" and let's move forward.

-Steve