Function _mm256_inserti128_si256

pub unsafe fn _mm256_inserti128_si256(
    a: __m256i,
    b: __m128i,
    const IMM1: i32,
) -> __m256i

Available on (x86 or x86-64) and target feature avx2 and x86 only.

Copies a to dst, then insert 128 bits (of integer data) from b at the location specified by IMM1.

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