```
pub unsafe fn _mm256_gf2p8affineinv_epi64_epi8<const B: i32>(
x: __m256i,
a: __m256i
) -> __m256i
```

🔬This is a nightly-only experimental API. (

`stdsimd`

#48556)Available on

**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.