Function _mm256_mask_compress_pd 

pub fn _mm256_mask_compress_pd(src: __m256d, k: __mmask8, a: __m256d) -> __m256d

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

Contiguously store the active double-precision (64-bit) floating-point elements 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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