pub unsafe fn _mm512_mask_extracti64x4_epi64(
    src: __m256i,
    k: __mmask8,
    a: __m512i,
    const IMM1: i32
) -> __m256i
🔬This is a nightly-only experimental API. (stdarch_x86_avx512 #111137)
Available on (x86 or x86-64) and target feature avx512f and x86-64 only.
Expand description

Extract 256 bits (composed of 4 packed 64-bit integers) from a, selected with IMM1, and store the results in dst using writemask k (elements are copied from src when the corresponding mask bit is not set).

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