Function _mm256_maskz_gf2p8affine_epi64_epi8

#[target_feature(enable = "gfni", enable = "avx512bw", enable = "avx512vl")]
pub fn _mm256_maskz_gf2p8affine_epi64_epi8(k: __mmask32, x: __m256i, a: __m256i, B: i32) -> __m256i

Performs 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 zeroed in the result if the corresponding mask bit is not set. Otherwise the computation result is written into the result.

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