Function _mm512_mask_extracti64x4_epi64

#[target_feature(enable = "avx512f")]
pub const fn _mm512_mask_extracti64x4_epi64(src: __m256i, k: __mmask8, a: __m512i, IMM1: i32) -> __m256i

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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