pub unsafe fn _mm256_mask_permutex_epi64(
    src: __m256i,
    k: __mmask8,
    a: __m256i,
    const MASK: i32
) -> __m256i
🔬 This is a nightly-only experimental API. (stdsimd #48556)
This is supported on x86-64 and target feature avx512f,avx512vl only.
Expand description

Shuffle 64-bit integers in a within 256-bit lanes using the control in imm8, and store the results in dst using writemask k (elements are copied from src when the corresponding mask bit is not set).

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