Function _mm_mask_compress_epi64 

pub fn _mm_mask_compress_epi64(src: __m128i, k: __mmask8, a: __m128i) -> __m128i

Available on x86-64 and target feature avx512f and target feature avx512vl only.

Contiguously store the active 64-bit integers in a (those with their respective bit set in writemask k) to dst, and pass through the remaining elements from src.

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