pub unsafe fn _mm512_mask2_permutex2var_epi64(
    a: __m512i,
    idx: __m512i,
    k: __mmask8,
    b: __m512i
) -> __m512i
🔬 This is a nightly-only experimental API. (stdsimd #48556)
Available on x86-64 and target feature avx512f only.
Expand description

Shuffle 64-bit integers in a and b across lanes using the corresponding selector and index in idx, and store the results in dst using writemask k (elements are copied from idx when the corresponding mask bit is not set).

Intel’s documentation