Currently, we have a whole lot of code that deals with null-checking in our LRB expansion:
- We generate a null-check before the cset-check. This used to be necessary when cset-check could not handle null, and because we did read the mark-word from the object. Both is no longer the case.
- We shuffle around preceding or subsequent null-checks, and clone a null-check into the LRB midpath, all of which was necessary to make the null-check in mid-path be transformed into an implicit null-check. It's not needed anymore either.