Function _mm256_mmask_i64gather_pd 

pub unsafe fn _mm256_mmask_i64gather_pd(
    src: __m256d,
    k: __mmask8,
    vindex: __m256i,
    base_addr: *const f64,
    const SCALE: i32,
) -> __m256d

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

Loads 4 double-precision (64-bit) floating-point elements from memory starting at location base_addr at packed 32-bit integer indices stored in vindex scaled by scale using writemask k (elements are copied from src when the corresponding mask bit is not set).

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