I've yet to see a compiler that can beat a human hand-optimizing. It's true that for zero effort the compiler can usually do better but if you really care abou

I've yet to see a compiler that can beat a human hand-optimizing. It's true that for zero effort the compiler can usually do better but if you really care about performance you need to get around those abstractions. I worked on a wavelet video decoder, after a while we had a pretty optimized C code that used SSE intrinsics for large portions of the decode. Some clever guy spent 3 months and rewrote the entire decoder in assembly. It involved careful data layout and optimizing the instruction sequences. It ran more than twice as fast than our hand optimized C code. Same algorithm, input and output.