core::arch::x86_64

Function _mm256_maskz_gf2p8affineinv_epi64_epi8

source 
pub unsafe fn _mm256_maskz_gf2p8affineinv_epi64_epi8(
    k: __mmask32,
    x: __m256i,
    a: __m256i,
    const B: i32,
) -> __m256i
🔬This is a nightly-only experimental API. (stdarch_x86_avx512 #111137)
Available on (x86 or x86-64) and target feature gfni,avx512bw,avx512vl and x86-64 only.
Expand description

Performs an affine transformation on the inverted packed bytes in x. That is computes a*inv(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. The inverse of a byte is defined with respect to the reduction polynomial x^8+x^4+x^3+x+1. The inverse of 0 is 0. 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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