Function `_mm512_mask_extractf64x4_pd`

#[target_feature(enable = "avx512f")]
pub const fn _mm512_mask_extractf64x4_pd(src: __m256d, k: __mmask8, a: __m512d, IMM8: i32) -> __m256d

Extract 256 bits (composed of 4 packed double-precision (64-bit) floating-point elements) from a, selected with imm8, 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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