In rust there is `#[cold]` for functions as well as (nightly only) `likely(cond)`/`unlikely(cond)` and some tricks you can have something similar in stable rust

In rust there is `#[cold]` for functions as well as (nightly only) `likely(cond)`/`unlikely(cond)` and some tricks you can have something similar in stable rust. Also branch paths which lead guaranteed to an panic tend to be treated as "unlikely" but not sure how far this is guaranteed.