37   class NodeSubset {
40     NodeSubset(BitVector e) : Elements(e) {}  in NodeSubset()  function
43     NodeSubset() : Elements(0) {  in NodeSubset()  function
48     bool operator==(const NodeSubset &other) const {
51     bool operator!=(const NodeSubset &other) const {
79     bool isSubsetOf(const NodeSubset &other) const {  in isSubsetOf()
84     NodeSubset Complement() const {  in Complement()
89     NodeSubset Join(const NodeSubset &other) const {  in Join()
94     NodeSubset Meet(const NodeSubset &other) const {  in Meet()
100   typedef std::pair<unsigned, NodeSubset> NodeType;
139   NodeSubset NodesReachableFrom(unsigned Idx) const {  in NodesReachableFrom()
142     NodeSubset Reachable;  in NodesReachableFrom()
147       NodeSubset Previous(Reachable);  in NodesReachableFrom()
170     NodeSubset Children;
174     ChildIterator(NodeType *F, NodeSubset C) : FirstNode(F), Children(C) {}  in ChildIterator()
230     return ChildIterator(Parent - Parent->first, NodeSubset());  in child_end()