Function _mm256_mask_alignr_epi32 

pub fn _mm256_mask_alignr_epi32(
    src: __m256i,
    k: __mmask8,
    a: __m256i,
    b: __m256i,
    const IMM8: i32,
) -> __m256i

Available on x86 and target feature avx512f and target feature avx512vl only.

Concatenate a and b into a 64-byte immediate result, shift the result right by imm8 32-bit elements, and store the low 32 bytes (8 elements) in dst using writemask k (elements are copied from src when the corresponding mask bit is not set).

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