Function _mm256_mask_gf2p8affine_epi64_epi8
#[target_feature(enable = "gfni", enable = "avx512bw", enable = "avx512vl")]
pub fn _mm256_mask_gf2p8affine_epi64_epi8(src: __m256i, k: __mmask32, x: __m256i, a: __m256i, B: i32) -> __m256iPerforms an affine transformation on the packed bytes in x. That is computes a*x+b over the Galois Field 2^8 for each packed byte with a being a 8x8 bit matrix and b being a constant 8-bit immediate value. Each pack of 8 bytes in x is paired with the 64-bit word at the same position in a.
Uses the writemask in k - elements are copied from src if the corresponding mask bit is not set. Otherwise the computation result is written into the result.