Function _mm256_zextph128_ph256 

pub fn _mm256_zextph128_ph256(a: __m128h) -> __m256h

Available on x86 and target feature avx512fp16 only.

Cast vector of type __m256h to type __m128h. The upper 8 elements of the result are zeroed. This intrinsic can generate the vzeroupper instruction, but most of the time it does not generate any instructions.

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