home.social

#avx512 — Public Fediverse posts

Live and recent posts from across the Fediverse tagged #avx512, aggregated by home.social.

  1. AVX-512's VPCOMPRESS instruction is so damn cool. For a simple array filtering problem (retain in-place only even 32-bit numbers out of a 256MiB array), it'll out-perform native C code by a factor of 10x. The C code executes at about 800MHz, while the AVX512 code executes at about 90MHz - it's just 100 times more productive with the cycles it executes.

    #avx512 #vectorization

  2. Holy shit, `VPSHLDQ` is so cool! On my laptop, the scalar `SHLD` on 64-bit GPRs is 1-3 cycles of latency. `VPSHLDQ` does the same thing (with a constant shift value, which is fine for my use case) on a 8x64-bit ZMM register with just 1 cycle of latency. I can perform the same operation 8-24 times faster!

    #simd #vectorization #avx512