We can, theoretically. We just haven't yet developed algorithms that are clever enough to make the correct optimizations to code in enough of the cases where su

We can, theoretically. We just haven't yet developed algorithms that are clever enough to make the correct optimizations to code in enough of the cases where such optimizations are possible. There are patterns in our code that we humans can write out when we write our code in C++, but that we haven't yet formalized and implemented for the computer to do.