Add df_iterator::getPathLength and getPath as a way of getting a path from the

entry node to the current node.

llvm-svn: 111392

llvm/include/llvm/ADT/DepthFirstIterator.h

@@ -183,6 +183,16 @@ public:
   inline bool nodeVisited(NodeType *Node) const {
     return this->Visited.count(Node) != 0;
   }
+
+  /// getPathLength - Return the length of the path from the entry node to the
+  /// current node, counting both nodes.
+  unsigned getPathLength() const { return VisitStack.size(); }
+
+  /// getPath - Return the n'th node in the path from the the entry node to the
+  /// current node.
+  NodeType *getPath(unsigned n) const {
+    return VisitStack[n].first.getPointer();
+  }
 };