simde (spack): The SIMDe header-only library provides fast, portable implementations of SIMD intrinsics on hardware which doesn't natively support them, such as calling SSE functions on ARM. There is no performance penalty if the hardware supports the native implementation (e.g., SSE/AVX runs at full speed on x86, NEON on ARM, etc.). 
Keywords: altivec|arm|arm64|avx|avx2|avx512|fma|gfni|mmx|neon|powerpc|simd|simd-intrinsics|sse|sse2|sse3|sse41|sse42|ssse3|vectorization