Function _mm512_mask_expand_epi64

#[target_feature(enable = "avx512f")]
pub fn _mm512_mask_expand_epi64(src: __m512i, k: __mmask8, a: __m512i) -> __m512i

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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