pub unsafe fn _mm256_mask_permutex2var_pd(
    a: __m256d,
    k: __mmask8,
    idx: __m256i,
    b: __m256d
) -> __m256d
🔬 This is a nightly-only experimental API. (stdsimd #48556)
Available on x86-64 and target feature avx512f,avx512vl only.
Expand description

Shuffle double-precision (64-bit) floating-point elements 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 a when the corresponding mask bit is not set).

Intel’s documentation