Function _mm256_maddubs_epi16

#[target_feature(enable = "avx2")]
pub fn _mm256_maddubs_epi16(a: __m256i, b: __m256i) -> __m256i

Vertically multiplies each unsigned 8-bit integer from a with the corresponding signed 8-bit integer from b, producing intermediate signed 16-bit integers. Horizontally add adjacent pairs of intermediate signed 16-bit integers

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