Function _mm_mask_packus_epi16 

pub fn _mm_mask_packus_epi16(
    src: __m128i,
    k: __mmask16,
    a: __m128i,
    b: __m128i,
) -> __m128i

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

Convert packed signed 16-bit integers from a and b to packed 8-bit integers using unsigned saturation, 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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