Function _mm512_mask_cvtepi8_epi16

pub fn _mm512_mask_cvtepi8_epi16(src: __m512i, k: u32, a: __m256i) -> __m512i

Sign extend packed 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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