Re: ABI change for device drivers using future AVX instruction set

[H. Peter Anvin]

Arjan van de Ven wrote:
> Let me repeat this loud and clear:
>
> It is not allowed to use floating point, SSE of AVX in device drivers.
>
> (there are few places that very carefully do this anyway, the raid5
> code being the most obvious one, but we should not add more)

Sadly, AVX repeats the mistakes of SSE1, and doesn't implement proper 
wide support for integer operations.  It has the basic bitwide stuff, 
which makes it usable for RAID-5, but it doesn't extend MMX (which SSE2 
eventually got around to), so it's not usable for RAID-6.  I'd hoped to 
find a VPERM-style instruction, like SSE5 has :(

	-hpa
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