Function _mm_mask_set1_epi8 

pub fn _mm_mask_set1_epi8(src: __m128i, k: __mmask16, a: i8) -> __m128i

Available on x86-64 and target feature avx512bw and target feature avx512vl only.

Broadcast 8-bit integer a to all elements of dst using writemask k (elements are copied from src when the corresponding mask bit is not set).

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