Function _mm512_madd_epi16

#[target_feature(enable = "avx512bw")]
pub fn _mm512_madd_epi16(a: __m512i, b: __m512i) -> __m512i

Multiply packed signed 16-bit integers in a and b, producing intermediate signed 32-bit integers. Horizontally add adjacent pairs of intermediate 32-bit integers, and pack the results in dst.

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