Rewrite the Andersen code to use the State monad to track the worklist, current graph, and depgraph.
Rewrite the Andersen code to use the State monad to track the worklist, current graph, and depgraph.

The code is clearer and shorter this way.  It is also easier to plug
in new bits without having to worry as much about the extra
parameters.

travitch/llvm-analysis,wangxiayang/llvm-analysis,travitch/llvm-analysis,wangxiayang/llvm-analysis