[Symmetry]

An optimizing cispiler sounds really interesting. Something that applies all the optimizations that the compiler would do when translating your C to machine code but showing you the results in C. Of course not all optimizations are representable in C (calling conventions for instance) but many are.

[jmgao]

There are several examples of this in the Java world, such as proguard. They're mostly centered around code obfuscation, but they do some useful optimizations as well.