Function _mm256_fmsubadd_ph 

pub fn _mm256_fmsubadd_ph(a: __m256h, b: __m256h, c: __m256h) -> __m256h

Multiply packed half-precision (16-bit) floating-point elements in a and b, alternatively subtract and add packed elements in c to/from the intermediate result, and store the results in dst.

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