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Date: Mon, 26 Sep 2011 22:52:09 +0300
From: Avi Kivity <avi@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH] tcg: Remove stack protection from helper
 functions
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To: Richard Henderson <rth@twiddle.net>
Cc: Laurent Desnogues <laurent.desnogues@gmail.com>, Jan Kiszka <jan.kiszka@siemens.com>, Mulyadi Santosa <mulyadi.santosa@gmail.com>, qemu-devel <qemu-devel@nongnu.org>

On 09/26/2011 10:43 PM, Richard Henderson wrote:
> On 09/26/2011 10:41 AM, Avi Kivity wrote:
> >  Native tcg ops for common vector instructions would probably be quite a speedup.
>
> It's very possible to simply open-code many of the vector operations.
>
> I've done a port of qemu to the SPU (aka Cell) processor.  This core
> has no scalar operations; all operations are on vectors.  It turned
> out fairly well for the basic arithmetic.  I only have to fall back
> on helpers for the more esoteric operations.
>
> That said, all FP vector operations should of course continue to be
> done completely via helpers, since one would need helpers for the
> individual FP operations anyway.

Why do floating point ops need helpers?  At least if all the edge cases 
match? (i.e. NaNs and denormals)

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.