This has never quite been my experience. Look-mummy-my-first-SIMD-routine is usually within spitting distance of the compiler's best effort, and a lot neater-lo

This has never quite been my experience. Look-mummy-my-first-SIMD-routine is usually within spitting distance of the compiler's best effort, and a lot neater-looking. Then you can just take it from there. The compiler's output is far from useless, because compilers generally know a few tricks and/or cute sequences that you can copy. And using intrinsics is certainly better than relying on it to automatically vectorize things itself - I've never heard of that do anything remotely interesting. But, even though it's 2013, it still seems like the compiler is easier to beat by hand than you'd think. I make no claim that this is worth doing in every case. (As for the suggestion that the compiler can't rearrange inline assembly language, or provide symbolic register names - whyever not? Perhaps people have been conditioned by gcc and VC++ never to expect anything except the absolute bare minimum from inline assembly language support, but that's no reason to assume that these tasks are impossible. Code Warrior for Wii would rearrange assembly language for you to avoid holdups due to instruction latencies, and while automatically assigning registers for you. I believe most modern assemblers will do similar reordering and at least let you assign names to the registers you're using.)