[gauge_field]

Yeah, it so fast that AMD is not even able to catchup and that many of the extensions is available only on Intel CPUs.

As far as I could tell, it is only unstable in the sense of being fast and having many features. I dont see any breaking for my code using cpuid to detect avx512 features.

[bobmcnamara]

No, I mean things like when they removed BCD support, or when they removed simultaneous 16-bit ISA when they added 64-bit. Or the bit string instructions. Or moving the cmpxchg encoding across chip revisions.