diff --git a/include/llvm/Analysis/DSGraph.h b/include/llvm/Analysis/DSGraph.h
index 9324cb7a3c7..2a683655851 100644
--- a/include/llvm/Analysis/DSGraph.h
+++ b/include/llvm/Analysis/DSGraph.h
@@ -473,7 +473,12 @@ class DSGraph {
 public:
   DSGraph() : Func(0) {}           // Create a new, empty, DSGraph.
   DSGraph(Function &F);            // Compute the local DSGraph
-  DSGraph(const DSGraph &DSG);     // Copy ctor
+
+  // Copy ctor - If you want to capture the node mapping between the source and
+  // destination graph, you may optionally do this by specifying a map to record
+  // this into.
+  DSGraph(const DSGraph &DSG);
+  DSGraph(const DSGraph &DSG, std::map<const DSNode*, DSNode*> &BUNodeMapTy);
   ~DSGraph();
 
   bool hasFunction() const { return Func != 0; }
diff --git a/include/llvm/Analysis/DataStructure/DSGraph.h b/include/llvm/Analysis/DataStructure/DSGraph.h
index 9324cb7a3c7..2a683655851 100644
--- a/include/llvm/Analysis/DataStructure/DSGraph.h
+++ b/include/llvm/Analysis/DataStructure/DSGraph.h
@@ -473,7 +473,12 @@ class DSGraph {
 public:
   DSGraph() : Func(0) {}           // Create a new, empty, DSGraph.
   DSGraph(Function &F);            // Compute the local DSGraph
-  DSGraph(const DSGraph &DSG);     // Copy ctor
+
+  // Copy ctor - If you want to capture the node mapping between the source and
+  // destination graph, you may optionally do this by specifying a map to record
+  // this into.
+  DSGraph(const DSGraph &DSG);
+  DSGraph(const DSGraph &DSG, std::map<const DSNode*, DSNode*> &BUNodeMapTy);
   ~DSGraph();
 
   bool hasFunction() const { return Func != 0; }
diff --git a/lib/Analysis/DataStructure/DataStructure.cpp b/lib/Analysis/DataStructure/DataStructure.cpp
index cc0b8d8fc5a..4b3be84aaf5 100644
--- a/lib/Analysis/DataStructure/DataStructure.cpp
+++ b/lib/Analysis/DataStructure/DataStructure.cpp
@@ -371,6 +371,11 @@ DSGraph::DSGraph(const DSGraph &G) : Func(G.Func) {
   RetNode = cloneInto(G, ValueMap, NodeMap);
 }
 
+DSGraph::DSGraph(const DSGraph &G, std::map<const DSNode*, DSNode*> &NodeMap)
+  : Func(G.Func) {
+  RetNode = cloneInto(G, ValueMap, NodeMap);
+}
+
 DSGraph::~DSGraph() {
   FunctionCalls.clear();
   ValueMap.clear();