> After preliminary discussions with CPU vendors, we propose AVX2
> new baseline. AVX2 support was introduced into CPUs from 2013 to
> 2015. See [https://en.wikipedia.org/wiki/Advanced_Vector_Extensions#CPUs_with_AVX2
> CPUs with AVX2].
This is not what I'd call a good idea. I've had to shoot it down
several times on internal mailing lists for RHEL, I think it's even
less a good idea for Fedora.
Skylake Pentium and Celeron models - dating from 2015 - don't have AVX
at all. Why do we want to break them? Has Intel promised they're not
going to pull a trick like that again?
If we really want to chase after Clear Linux benchmarks then fix ld.so
to know that avx2 is a capability (like we could for i686 + sse2).
Moving the baseline like this is far, far too aggressive.
IBM did something to run optimised Power9 binaries on Power8, if I
remember correctly it was IFUNC in glibc, so they could have optimised
paths so I don't see why the same sort of thing couldn't be used for
If Intel is so determined to make their processors look remotely
competitive again with the likes of Spectre and Meltown maybe they
should look into things like that?
Looking at the Intel x86 devices we're supporting for IoT, even the
latest available, none of them report any form of AVX.