C Back-End

I looked at various manners of binding LLVM to Hi. It ain't easy. The most direct would be to just use Hi's FFI for an LLVM-Hi binding, but LLVM has a big back-end, and it is written in C++, whereas Hi binds to C. The best route to take looks like to 'double' the code of the internal assembly used in C with a library for that, and -at some point- write an LLVM back-end instead of a C back-end. It would speed up the emitting phase I hope since it wouldn't need (text emitting) functions written in Hi, which are pretty slow at the moment.