Function _mm256_mask_cvtepu8_epi16 

pub fn _mm256_mask_cvtepu8_epi16(
    src: __m256i,
    k: __mmask16,
    a: __m128i,
) -> __m256i

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

Zero extend packed unsigned 8-bit integers in a to packed 16-bit integers, 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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