Function _mm512_mask_compressstoreu_epi64 

pub unsafe fn _mm512_mask_compressstoreu_epi64(
    base_addr: *mut i64,
    k: __mmask8,
    a: __m512i,
)

Available on x86-64 and target feature avx512f only.

Contiguously store the active 64-bit integers in a (those with their respective bit set in writemask k) to unaligned memory at base_addr.

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