Function core::arch::x86::_mm256_alignr_epi8

pub unsafe fn _mm256_alignr_epi8(a: __m256i, b: __m256i, n: i32) -> __m256i

This is supported on x86 and target feature avx2 only.

Concatenate pairs of 16-byte blocks in a and b into a 32-byte temporary result, shift the result right by n bytes, and return the low 16 bytes.

Intel's documentation