code: Collection<Node> getUses(String name, Node defNode) {
      GraphNode<Node, Branch> n = getCfg().getNode(defNode);
      checkNotNull(n);
      FlowState<ReachingUses> state = n.getAnnotation();
      return state.getOut().mayUseMap.get(allVarsInFn.get(name));
    }
docs: Gets a list of nodes that may be using the value assigned to {@code name}
  in {@code defNode}. {@code defNode} must be one of the control flow graph
  nodes.
  
  @param name name of the variable. It can only be names of local variable
  that are not function parameters, escaped variables or variables
  declared in catch.
  @param defNode The list of upward exposed use for the variable.