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Subject: Re: [Qemu-devel] [PATCH] tcg: Remove stack protection from helper
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To: Avi Kivity <avi@redhat.com>
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 10:41 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.


r~