pub unsafe fn _mm_mask_expand_epi64(
    src: __m128i,
    k: __mmask8,
    a: __m128i
) -> __m128i
🔬 This is a nightly-only experimental API. (stdsimd #48556)
Available on x86 and target feature avx512f,avx512vl only.
Expand description

Load contiguous active 64-bit integers from a (those with their respective bit set in mask k), 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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