Function _mm512_insertf64x2 

pub fn _mm512_insertf64x2(a: __m512d, b: __m128d, const IMM8: i32) -> __m512d

Available on x86-64 and target feature avx512dq only.

Copy a to dst, then insert 128 bits (composed of 2 packed double-precision (64-bit) floating-point elements) from b into dst at the location specified by IMM8.

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