Function _mm256_insertf128_pd 

pub fn _mm256_insertf128_pd(a: __m256d, b: __m128d, const IMM1: i32) -> __m256d

Available on x86-64 and target feature avx only.

Copies a to result, then inserts 128 bits (composed of 2 packed double-precision (64-bit) floating-point elements) from b into result at the location specified by imm8.

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