This package is a rewrite of the null-pointer analysis to use sets of value numbers rather than frames. The main advantage of this approach is that it requires no special code to handle the case where a value is stored in the heap and re-appears in a subsequent field load.

This isn't ready for prime time, but may be in the future. Or maybe we'll rewrite the entire dataflow analysis package to use a different bytecode framework, and it will never be used. Hard to say for sure.