Added level information in the dataflow graph.

llvm/include/llvm/IR/DFGraph.h

@@ -147,6 +147,8 @@ private:
   DFEdgeListType OutDFEdges;      ///< List of outgoing edges i.e.,
                                   ///< DFEdges originating from this DFNode to
                                   ///< successor DFNodes
+  int Level;                      ///< Distance to the top-level DFNode in the
+                                  ///< hierarchy
 
 public:
   // Iterators
@@ -214,7 +216,9 @@ public:
   DFNode(IntrinsicInst* _II, Function* _FuncPointer, DFNode* _Parent,
          int _NumOfDim, std::vector<Value*> _DimLimits) : II(_II),
          FuncPointer(_FuncPointer), Parent(_Parent), NumOfDim(_NumOfDim),
-         DimLimits(_DimLimits) {}
+         DimLimits(_DimLimits) {
+    Level = (_Parent) ? _Parent->getLevel() + 1 : 0 ;
+  }
 
   void addSuccessor(DFNode* N) {
     Successors.push_back(N);
@@ -234,6 +238,9 @@ public:
     return FuncPointer;
   }
 
+  int getLevel() {
+    return Level;
+  }
 
   virtual void applyDFNodeVisitor(DFNodeVisitor &V) = 0;
 //  virtual void applyDFEdgeVisitor(DFEdgeVisitor &V) = 0;