A Hint for Language-Specific Runtime Function Optimization in RPython's Meta-JIT

Meta Note: This post was in my draft folder for the PyPy blog for three years, and various people gave the feedback "wtf are you even talking about". Since I haven't worked on it since then I clearly am not going to fix anything about it, so I'll just post it almost unchanged to my personal blog now. RPython's meta-JIT cannot reason about the properties of many RPython implementation-level…