Function _mm256_mask_insertf64x2

#[target_feature(enable = "avx512dq", enable = "avx512vl")]
pub const fn _mm256_mask_insertf64x2(src: __m256d, k: __mmask8, a: __m256d, b: __m128d, IMM8: i32) -> __m256d

Copy a to tmp, then insert 128 bits (composed of 2 packed double-precision (64-bit) floating-point elements) from b into tmp at the location specified by IMM8, and copy tmp to dst using writemask k (elements are copied from src if the corresponding bit is not set).

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