Function core_arch::x86::_mm_hadd_epi32

pub unsafe fn _mm_hadd_epi32(a: __m128i, b: __m128i) -> __m128i

This is supported on x86 and target feature ssse3 only.

Horizontally adds the adjacent pairs of values contained in 2 packed 128-bit vectors of [4 x i32].

Intel's documentation