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Re: Altivec in baseline for ppc64?

crowd-funded eco-conscious hardware: https://www.crowdsupply.com/eoma68

On Fri, Jul 16, 2021 at 2:55 PM Lennart Sorensen
<lsorense@csclub.uwaterloo.ca> wrote:

> Some years ago I tried to get such runtime detection added for vlc.
> Upstream was certainly far from helpful and just about hostile to the
> idea of adding runtime detection code on powerpc.

because "why would you support 10+ year old processors", i do get it,
but it is very frustrating.

>  Given I was just
> trying to help out the people hitting a problem with it (I don't have
> any desktop powerpc, I only deal with embedded), I decided it wasn't
> worth my effort to argue with them.

Libre-SOC's SVP64 ISA is a stunning 4 to 5 times less instructions for MP3
CODEC inner loop.  i'm also adding hardware-level support for in-place
FFT butterfly, such that *any* sized FFT should be possible to do in around
45 instructions.

when hardware's available this _should_ shock ffmpeg and other
developers out of rejecting upstream patches for non-IBM non-SIMD

... but the more mandatory patches "#ifdef POWER9" include VSX,
the harder that becomes to do, because our processor will be POWER9
compliant... just without SIMD.


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