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Re: Altivec in baseline for ppc64?

> On Fri, Jul 16, 2021 at 12:09 PM John Paul Adrian Glaubitz
> <glaubitz@physik.fu-berlin.de> wrote:
> >
> > On 7/16/21 12:59 PM, Jeffrey Walton wrote:
> > > Does it have to be one or the other? Can't you have both?
> >
> > Well, you could have runtime detection like certain multimedia codes and OpenSSL use but
> > most packages don't do that.
> this is the "sane" way to do it.  unfortunately, the EABIv2, which
> *explicitly* states, "SIMD is mandatory" is resulting in an inexorable
> creep of submissions from IBM developers (to libc6 and other
> libraries)

I never really took notice that IBM captured the projects. But with
your lens it sounds about right.

("Captured", as in regulatory capture as seen in the US. Regulatory
capture is where private industry gets so cozy with government and
regulators that industry writes their own rules and gov is just an
extension of a few dominant players).

> with Quad and 8 1.5+ ghz on the roadmap over the next 3 years,
> Libre-SOC's processor is *not* intended for just "embedded" uses.
> we've simply made it abundantly clear that Hell Will Freeze Over
> before we add a suicidal *700* SIMD instructions to what is supposed
> to be a RISC design.

Forgive my ignorance... Once traces of companies like NXP and IBM are
removed, and Altivec is removed, what is left? Are some pieces of the
ISA going to be (re)used? Or is the ISA being built from scratch? Is
it even PowerPC anymore? Is it just a RISC machine?

(PowerPC scatter/gather is quite lame, even in the latest ISA 3.0B, so
I'm not sure there's much good stuff to reuse).

Anyway, I'm excited to see a SIMD alternative that could become
mainstream. I really look forward to the new hardware making it to


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