pub unsafe fn _mm256_mask2_permutex2var_epi64(
    a: __m256i,
    idx: __m256i,
    k: u8,
    b: __m256i
) -> __m256i
🔬 This is a nightly-only experimental API. (stdsimd)
This is supported on x86-64 and target feature avx512f,avx512vl 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).

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