Function _mm512_maskz_set1_epi8 

pub fn _mm512_maskz_set1_epi8(k: __mmask64, a: i8) -> __m512i

Available on x86-64 and target feature avx512bw only.

Broadcast 8-bit integer a to all elements of dst using zeromask k (elements are zeroed out when the corresponding mask bit is not set).

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