pub unsafe fn _mm256_mask_compress_pd(
    src: __m256d,
    k: __mmask8,
    a: __m256d
) -> __m256d
🔬This is a nightly-only experimental API. (stdsimd #48556)
Available on (x86 or x86-64) and target feature avx512f,avx512vl and x86 only.
Expand description

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.

Intel’s documentation