Function _mm512_mask_max_epu64 

pub fn _mm512_mask_max_epu64(
    src: __m512i,
    k: __mmask8,
    a: __m512i,
    b: __m512i,
) -> __m512i

Available on x86 and target feature avx512f only.

Compare packed unsigned 64-bit integers in a and b, and store packed maximum values in dst using writemask k (elements are copied from src when the corresponding mask bit is not set).

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