diff --git a/include/llvm/CodeGen/MachineDominators.h b/include/llvm/CodeGen/MachineDominators.h
index f50c61876c2..608833305f9 100644
--- a/include/llvm/CodeGen/MachineDominators.h
+++ b/include/llvm/CodeGen/MachineDominators.h
@@ -18,8 +18,8 @@
 #include "llvm/CodeGen/MachineBasicBlock.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
-#include "llvm/IR/DominatorInternals.h"
-#include "llvm/IR/Dominators.h"
+#include "llvm/Support/GenericDomTreeConstruction.h"
+#include "llvm/Support/GenericDomTree.h"
 
 namespace llvm {
 
diff --git a/include/llvm/IR/Dominators.h b/include/llvm/IR/Dominators.h
index 6a6e71e3144..9dc0860dbd9 100644
--- a/include/llvm/IR/Dominators.h
+++ b/include/llvm/IR/Dominators.h
@@ -20,706 +20,22 @@
 #include "llvm/ADT/GraphTraits.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SmallVector.h"
+#include "llvm/IR/BasicBlock.h"
 #include "llvm/IR/Function.h"
 #include "llvm/Pass.h"
 #include "llvm/Support/CFG.h"
+#include "llvm/Support/GenericDomTree.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/raw_ostream.h"
 #include <algorithm>
 
 namespace llvm {
 
-//===----------------------------------------------------------------------===//
-/// DominatorBase - Base class that other, more interesting dominator analyses
-/// inherit from.
-///
-template <class NodeT>
-class DominatorBase {
-protected:
-  std::vector<NodeT*> Roots;
-  const bool IsPostDominators;
-  inline explicit DominatorBase(bool isPostDom) :
-    Roots(), IsPostDominators(isPostDom) {}
-public:
-
-  /// getRoots - Return the root blocks of the current CFG.  This may include
-  /// multiple blocks if we are computing post dominators.  For forward
-  /// dominators, this will always be a single block (the entry node).
-  ///
-  inline const std::vector<NodeT*> &getRoots() const { return Roots; }
-
-  /// isPostDominator - Returns true if analysis based of postdoms
-  ///
-  bool isPostDominator() const { return IsPostDominators; }
-};
-
-
-//===----------------------------------------------------------------------===//
-// DomTreeNode - Dominator Tree Node
-template<class NodeT> class DominatorTreeBase;
-struct PostDominatorTree;
-class MachineBasicBlock;
-
-template <class NodeT>
-class DomTreeNodeBase {
-  NodeT *TheBB;
-  DomTreeNodeBase<NodeT> *IDom;
-  std::vector<DomTreeNodeBase<NodeT> *> Children;
-  int DFSNumIn, DFSNumOut;
-
-  template<class N> friend class DominatorTreeBase;
-  friend struct PostDominatorTree;
-public:
-  typedef typename std::vector<DomTreeNodeBase<NodeT> *>::iterator iterator;
-  typedef typename std::vector<DomTreeNodeBase<NodeT> *>::const_iterator
-                   const_iterator;
-
-  iterator begin()             { return Children.begin(); }
-  iterator end()               { return Children.end(); }
-  const_iterator begin() const { return Children.begin(); }
-  const_iterator end()   const { return Children.end(); }
-
-  NodeT *getBlock() const { return TheBB; }
-  DomTreeNodeBase<NodeT> *getIDom() const { return IDom; }
-  const std::vector<DomTreeNodeBase<NodeT>*> &getChildren() const {
-    return Children;
-  }
-
-  DomTreeNodeBase(NodeT *BB, DomTreeNodeBase<NodeT> *iDom)
-    : TheBB(BB), IDom(iDom), DFSNumIn(-1), DFSNumOut(-1) { }
-
-  DomTreeNodeBase<NodeT> *addChild(DomTreeNodeBase<NodeT> *C) {
-    Children.push_back(C);
-    return C;
-  }
-
-  size_t getNumChildren() const {
-    return Children.size();
-  }
-
-  void clearAllChildren() {
-    Children.clear();
-  }
-
-  bool compare(const DomTreeNodeBase<NodeT> *Other) const {
-    if (getNumChildren() != Other->getNumChildren())
-      return true;
-
-    SmallPtrSet<const NodeT *, 4> OtherChildren;
-    for (const_iterator I = Other->begin(), E = Other->end(); I != E; ++I) {
-      const NodeT *Nd = (*I)->getBlock();
-      OtherChildren.insert(Nd);
-    }
-
-    for (const_iterator I = begin(), E = end(); I != E; ++I) {
-      const NodeT *N = (*I)->getBlock();
-      if (OtherChildren.count(N) == 0)
-        return true;
-    }
-    return false;
-  }
-
-  void setIDom(DomTreeNodeBase<NodeT> *NewIDom) {
-    assert(IDom && "No immediate dominator?");
-    if (IDom != NewIDom) {
-      typename std::vector<DomTreeNodeBase<NodeT>*>::iterator I =
-                  std::find(IDom->Children.begin(), IDom->Children.end(), this);
-      assert(I != IDom->Children.end() &&
-             "Not in immediate dominator children set!");
-      // I am no longer your child...
-      IDom->Children.erase(I);
-
-      // Switch to new dominator
-      IDom = NewIDom;
-      IDom->Children.push_back(this);
-    }
-  }
-
-  /// getDFSNumIn/getDFSNumOut - These are an internal implementation detail, do
-  /// not call them.
-  unsigned getDFSNumIn() const { return DFSNumIn; }
-  unsigned getDFSNumOut() const { return DFSNumOut; }
-private:
-  // Return true if this node is dominated by other. Use this only if DFS info
-  // is valid.
-  bool DominatedBy(const DomTreeNodeBase<NodeT> *other) const {
-    return this->DFSNumIn >= other->DFSNumIn &&
-      this->DFSNumOut <= other->DFSNumOut;
-  }
-};
-
 EXTERN_TEMPLATE_INSTANTIATION(class DomTreeNodeBase<BasicBlock>);
-EXTERN_TEMPLATE_INSTANTIATION(class DomTreeNodeBase<MachineBasicBlock>);
-
-template<class NodeT>
-inline raw_ostream &operator<<(raw_ostream &o,
-                               const DomTreeNodeBase<NodeT> *Node) {
-  if (Node->getBlock())
-    Node->getBlock()->printAsOperand(o, false);
-  else
-    o << " <<exit node>>";
-
-  o << " {" << Node->getDFSNumIn() << "," << Node->getDFSNumOut() << "}";
-
-  return o << "\n";
-}
-
-template<class NodeT>
-inline void PrintDomTree(const DomTreeNodeBase<NodeT> *N, raw_ostream &o,
-                         unsigned Lev) {
-  o.indent(2*Lev) << "[" << Lev << "] " << N;
-  for (typename DomTreeNodeBase<NodeT>::const_iterator I = N->begin(),
-       E = N->end(); I != E; ++I)
-    PrintDomTree<NodeT>(*I, o, Lev+1);
-}
+EXTERN_TEMPLATE_INSTANTIATION(class DominatorTreeBase<BasicBlock>);
 
 typedef DomTreeNodeBase<BasicBlock> DomTreeNode;
 
-//===----------------------------------------------------------------------===//
-/// DominatorTree - Calculate the immediate dominator tree for a function.
-///
-
-template<class FuncT, class N>
-void Calculate(DominatorTreeBase<typename GraphTraits<N>::NodeType>& DT,
-               FuncT& F);
-
-template<class NodeT>
-class DominatorTreeBase : public DominatorBase<NodeT> {
-  bool dominatedBySlowTreeWalk(const DomTreeNodeBase<NodeT> *A,
-                               const DomTreeNodeBase<NodeT> *B) const {
-    assert(A != B);
-    assert(isReachableFromEntry(B));
-    assert(isReachableFromEntry(A));
-
-    const DomTreeNodeBase<NodeT> *IDom;
-    while ((IDom = B->getIDom()) != 0 && IDom != A && IDom != B)
-      B = IDom;   // Walk up the tree
-    return IDom != 0;
-  }
-
-protected:
-  typedef DenseMap<NodeT*, DomTreeNodeBase<NodeT>*> DomTreeNodeMapType;
-  DomTreeNodeMapType DomTreeNodes;
-  DomTreeNodeBase<NodeT> *RootNode;
-
-  bool DFSInfoValid;
-  unsigned int SlowQueries;
-  // Information record used during immediate dominators computation.
-  struct InfoRec {
-    unsigned DFSNum;
-    unsigned Parent;
-    unsigned Semi;
-    NodeT *Label;
-
-    InfoRec() : DFSNum(0), Parent(0), Semi(0), Label(0) {}
-  };
-
-  DenseMap<NodeT*, NodeT*> IDoms;
-
-  // Vertex - Map the DFS number to the BasicBlock*
-  std::vector<NodeT*> Vertex;
-
-  // Info - Collection of information used during the computation of idoms.
-  DenseMap<NodeT*, InfoRec> Info;
-
-  void reset() {
-    for (typename DomTreeNodeMapType::iterator I = this->DomTreeNodes.begin(),
-           E = DomTreeNodes.end(); I != E; ++I)
-      delete I->second;
-    DomTreeNodes.clear();
-    IDoms.clear();
-    this->Roots.clear();
-    Vertex.clear();
-    RootNode = 0;
-  }
-
-  // NewBB is split and now it has one successor. Update dominator tree to
-  // reflect this change.
-  template<class N, class GraphT>
-  void Split(DominatorTreeBase<typename GraphT::NodeType>& DT,
-             typename GraphT::NodeType* NewBB) {
-    assert(std::distance(GraphT::child_begin(NewBB),
-                         GraphT::child_end(NewBB)) == 1 &&
-           "NewBB should have a single successor!");
-    typename GraphT::NodeType* NewBBSucc = *GraphT::child_begin(NewBB);
-
-    std::vector<typename GraphT::NodeType*> PredBlocks;
-    typedef GraphTraits<Inverse<N> > InvTraits;
-    for (typename InvTraits::ChildIteratorType PI =
-         InvTraits::child_begin(NewBB),
-         PE = InvTraits::child_end(NewBB); PI != PE; ++PI)
-      PredBlocks.push_back(*PI);
-
-    assert(!PredBlocks.empty() && "No predblocks?");
-
-    bool NewBBDominatesNewBBSucc = true;
-    for (typename InvTraits::ChildIteratorType PI =
-         InvTraits::child_begin(NewBBSucc),
-         E = InvTraits::child_end(NewBBSucc); PI != E; ++PI) {
-      typename InvTraits::NodeType *ND = *PI;
-      if (ND != NewBB && !DT.dominates(NewBBSucc, ND) &&
-          DT.isReachableFromEntry(ND)) {
-        NewBBDominatesNewBBSucc = false;
-        break;
-      }
-    }
-
-    // Find NewBB's immediate dominator and create new dominator tree node for
-    // NewBB.
-    NodeT *NewBBIDom = 0;
-    unsigned i = 0;
-    for (i = 0; i < PredBlocks.size(); ++i)
-      if (DT.isReachableFromEntry(PredBlocks[i])) {
-        NewBBIDom = PredBlocks[i];
-        break;
-      }
-
-    // It's possible that none of the predecessors of NewBB are reachable;
-    // in that case, NewBB itself is unreachable, so nothing needs to be
-    // changed.
-    if (!NewBBIDom)
-      return;
-
-    for (i = i + 1; i < PredBlocks.size(); ++i) {
-      if (DT.isReachableFromEntry(PredBlocks[i]))
-        NewBBIDom = DT.findNearestCommonDominator(NewBBIDom, PredBlocks[i]);
-    }
-
-    // Create the new dominator tree node... and set the idom of NewBB.
-    DomTreeNodeBase<NodeT> *NewBBNode = DT.addNewBlock(NewBB, NewBBIDom);
-
-    // If NewBB strictly dominates other blocks, then it is now the immediate
-    // dominator of NewBBSucc.  Update the dominator tree as appropriate.
-    if (NewBBDominatesNewBBSucc) {
-      DomTreeNodeBase<NodeT> *NewBBSuccNode = DT.getNode(NewBBSucc);
-      DT.changeImmediateDominator(NewBBSuccNode, NewBBNode);
-    }
-  }
-
-public:
-  explicit DominatorTreeBase(bool isPostDom)
-    : DominatorBase<NodeT>(isPostDom), DFSInfoValid(false), SlowQueries(0) {}
-  virtual ~DominatorTreeBase() { reset(); }
-
-  /// compare - Return false if the other dominator tree base matches this
-  /// dominator tree base. Otherwise return true.
-  bool compare(DominatorTreeBase &Other) const {
-
-    const DomTreeNodeMapType &OtherDomTreeNodes = Other.DomTreeNodes;
-    if (DomTreeNodes.size() != OtherDomTreeNodes.size())
-      return true;
-
-    for (typename DomTreeNodeMapType::const_iterator
-           I = this->DomTreeNodes.begin(),
-           E = this->DomTreeNodes.end(); I != E; ++I) {
-      NodeT *BB = I->first;
-      typename DomTreeNodeMapType::const_iterator OI = OtherDomTreeNodes.find(BB);
-      if (OI == OtherDomTreeNodes.end())
-        return true;
-
-      DomTreeNodeBase<NodeT>* MyNd = I->second;
-      DomTreeNodeBase<NodeT>* OtherNd = OI->second;
-
-      if (MyNd->compare(OtherNd))
-        return true;
-    }
-
-    return false;
-  }
-
-  virtual void releaseMemory() { reset(); }
-
-  /// getNode - return the (Post)DominatorTree node for the specified basic
-  /// block.  This is the same as using operator[] on this class.
-  ///
-  inline DomTreeNodeBase<NodeT> *getNode(NodeT *BB) const {
-    return DomTreeNodes.lookup(BB);
-  }
-
-  /// getRootNode - This returns the entry node for the CFG of the function.  If
-  /// this tree represents the post-dominance relations for a function, however,
-  /// this root may be a node with the block == NULL.  This is the case when
-  /// there are multiple exit nodes from a particular function.  Consumers of
-  /// post-dominance information must be capable of dealing with this
-  /// possibility.
-  ///
-  DomTreeNodeBase<NodeT> *getRootNode() { return RootNode; }
-  const DomTreeNodeBase<NodeT> *getRootNode() const { return RootNode; }
-
-  /// Get all nodes dominated by R, including R itself.
-  void getDescendants(NodeT *R, SmallVectorImpl<NodeT *> &Result) const {
-    Result.clear();
-    const DomTreeNodeBase<NodeT> *RN = getNode(R);
-    if (RN == NULL)
-      return; // If R is unreachable, it will not be present in the DOM tree.
-    SmallVector<const DomTreeNodeBase<NodeT> *, 8> WL;
-    WL.push_back(RN);
-
-    while (!WL.empty()) {
-      const DomTreeNodeBase<NodeT> *N = WL.pop_back_val();
-      Result.push_back(N->getBlock());
-      WL.append(N->begin(), N->end());
-    }
-  }
-
-  /// properlyDominates - Returns true iff A dominates B and A != B.
-  /// Note that this is not a constant time operation!
-  ///
-  bool properlyDominates(const DomTreeNodeBase<NodeT> *A,
-                         const DomTreeNodeBase<NodeT> *B) {
-    if (A == 0 || B == 0)
-      return false;
-    if (A == B)
-      return false;
-    return dominates(A, B);
-  }
-
-  bool properlyDominates(const NodeT *A, const NodeT *B);
-
-  /// isReachableFromEntry - Return true if A is dominated by the entry
-  /// block of the function containing it.
-  bool isReachableFromEntry(const NodeT* A) const {
-    assert(!this->isPostDominator() &&
-           "This is not implemented for post dominators");
-    return isReachableFromEntry(getNode(const_cast<NodeT *>(A)));
-  }
-
-  inline bool isReachableFromEntry(const DomTreeNodeBase<NodeT> *A) const {
-    return A;
-  }
-
-  /// dominates - Returns true iff A dominates B.  Note that this is not a
-  /// constant time operation!
-  ///
-  inline bool dominates(const DomTreeNodeBase<NodeT> *A,
-                        const DomTreeNodeBase<NodeT> *B) {
-    // A node trivially dominates itself.
-    if (B == A)
-      return true;
-
-    // An unreachable node is dominated by anything.
-    if (!isReachableFromEntry(B))
-      return true;
-
-    // And dominates nothing.
-    if (!isReachableFromEntry(A))
-      return false;
-
-    // Compare the result of the tree walk and the dfs numbers, if expensive
-    // checks are enabled.
-#ifdef XDEBUG
-    assert((!DFSInfoValid ||
-            (dominatedBySlowTreeWalk(A, B) == B->DominatedBy(A))) &&
-           "Tree walk disagrees with dfs numbers!");
-#endif
-
-    if (DFSInfoValid)
-      return B->DominatedBy(A);
-
-    // If we end up with too many slow queries, just update the
-    // DFS numbers on the theory that we are going to keep querying.
-    SlowQueries++;
-    if (SlowQueries > 32) {
-      updateDFSNumbers();
-      return B->DominatedBy(A);
-    }
-
-    return dominatedBySlowTreeWalk(A, B);
-  }
-
-  bool dominates(const NodeT *A, const NodeT *B);
-
-  NodeT *getRoot() const {
-    assert(this->Roots.size() == 1 && "Should always have entry node!");
-    return this->Roots[0];
-  }
-
-  /// findNearestCommonDominator - Find nearest common dominator basic block
-  /// for basic block A and B. If there is no such block then return NULL.
-  NodeT *findNearestCommonDominator(NodeT *A, NodeT *B) {
-    assert(A->getParent() == B->getParent() &&
-           "Two blocks are not in same function");
-
-    // If either A or B is a entry block then it is nearest common dominator
-    // (for forward-dominators).
-    if (!this->isPostDominator()) {
-      NodeT &Entry = A->getParent()->front();
-      if (A == &Entry || B == &Entry)
-        return &Entry;
-    }
-
-    // If B dominates A then B is nearest common dominator.
-    if (dominates(B, A))
-      return B;
-
-    // If A dominates B then A is nearest common dominator.
-    if (dominates(A, B))
-      return A;
-
-    DomTreeNodeBase<NodeT> *NodeA = getNode(A);
-    DomTreeNodeBase<NodeT> *NodeB = getNode(B);
-
-    // Collect NodeA dominators set.
-    SmallPtrSet<DomTreeNodeBase<NodeT>*, 16> NodeADoms;
-    NodeADoms.insert(NodeA);
-    DomTreeNodeBase<NodeT> *IDomA = NodeA->getIDom();
-    while (IDomA) {
-      NodeADoms.insert(IDomA);
-      IDomA = IDomA->getIDom();
-    }
-
-    // Walk NodeB immediate dominators chain and find common dominator node.
-    DomTreeNodeBase<NodeT> *IDomB = NodeB->getIDom();
-    while (IDomB) {
-      if (NodeADoms.count(IDomB) != 0)
-        return IDomB->getBlock();
-
-      IDomB = IDomB->getIDom();
-    }
-
-    return NULL;
-  }
-
-  const NodeT *findNearestCommonDominator(const NodeT *A, const NodeT *B) {
-    // Cast away the const qualifiers here. This is ok since
-    // const is re-introduced on the return type.
-    return findNearestCommonDominator(const_cast<NodeT *>(A),
-                                      const_cast<NodeT *>(B));
-  }
-
-  //===--------------------------------------------------------------------===//
-  // API to update (Post)DominatorTree information based on modifications to
-  // the CFG...
-
-  /// addNewBlock - Add a new node to the dominator tree information.  This
-  /// creates a new node as a child of DomBB dominator node,linking it into
-  /// the children list of the immediate dominator.
-  DomTreeNodeBase<NodeT> *addNewBlock(NodeT *BB, NodeT *DomBB) {
-    assert(getNode(BB) == 0 && "Block already in dominator tree!");
-    DomTreeNodeBase<NodeT> *IDomNode = getNode(DomBB);
-    assert(IDomNode && "Not immediate dominator specified for block!");
-    DFSInfoValid = false;
-    return DomTreeNodes[BB] =
-      IDomNode->addChild(new DomTreeNodeBase<NodeT>(BB, IDomNode));
-  }
-
-  /// changeImmediateDominator - This method is used to update the dominator
-  /// tree information when a node's immediate dominator changes.
-  ///
-  void changeImmediateDominator(DomTreeNodeBase<NodeT> *N,
-                                DomTreeNodeBase<NodeT> *NewIDom) {
-    assert(N && NewIDom && "Cannot change null node pointers!");
-    DFSInfoValid = false;
-    N->setIDom(NewIDom);
-  }
-
-  void changeImmediateDominator(NodeT *BB, NodeT *NewBB) {
-    changeImmediateDominator(getNode(BB), getNode(NewBB));
-  }
-
-  /// eraseNode - Removes a node from the dominator tree. Block must not
-  /// dominate any other blocks. Removes node from its immediate dominator's
-  /// children list. Deletes dominator node associated with basic block BB.
-  void eraseNode(NodeT *BB) {
-    DomTreeNodeBase<NodeT> *Node = getNode(BB);
-    assert(Node && "Removing node that isn't in dominator tree.");
-    assert(Node->getChildren().empty() && "Node is not a leaf node.");
-
-      // Remove node from immediate dominator's children list.
-    DomTreeNodeBase<NodeT> *IDom = Node->getIDom();
-    if (IDom) {
-      typename std::vector<DomTreeNodeBase<NodeT>*>::iterator I =
-        std::find(IDom->Children.begin(), IDom->Children.end(), Node);
-      assert(I != IDom->Children.end() &&
-             "Not in immediate dominator children set!");
-      // I am no longer your child...
-      IDom->Children.erase(I);
-    }
-
-    DomTreeNodes.erase(BB);
-    delete Node;
-  }
-
-  /// removeNode - Removes a node from the dominator tree.  Block must not
-  /// dominate any other blocks.  Invalidates any node pointing to removed
-  /// block.
-  void removeNode(NodeT *BB) {
-    assert(getNode(BB) && "Removing node that isn't in dominator tree.");
-    DomTreeNodes.erase(BB);
-  }
-
-  /// splitBlock - BB is split and now it has one successor. Update dominator
-  /// tree to reflect this change.
-  void splitBlock(NodeT* NewBB) {
-    if (this->IsPostDominators)
-      this->Split<Inverse<NodeT*>, GraphTraits<Inverse<NodeT*> > >(*this, NewBB);
-    else
-      this->Split<NodeT*, GraphTraits<NodeT*> >(*this, NewBB);
-  }
-
-  /// print - Convert to human readable form
-  ///
-  void print(raw_ostream &o) const {
-    o << "=============================--------------------------------\n";
-    if (this->isPostDominator())
-      o << "Inorder PostDominator Tree: ";
-    else
-      o << "Inorder Dominator Tree: ";
-    if (!this->DFSInfoValid)
-      o << "DFSNumbers invalid: " << SlowQueries << " slow queries.";
-    o << "\n";
-
-    // The postdom tree can have a null root if there are no returns.
-    if (getRootNode())
-      PrintDomTree<NodeT>(getRootNode(), o, 1);
-  }
-
-protected:
-  template<class GraphT>
-  friend typename GraphT::NodeType* Eval(
-                               DominatorTreeBase<typename GraphT::NodeType>& DT,
-                                         typename GraphT::NodeType* V,
-                                         unsigned LastLinked);
-
-  template<class GraphT>
-  friend unsigned DFSPass(DominatorTreeBase<typename GraphT::NodeType>& DT,
-                          typename GraphT::NodeType* V,
-                          unsigned N);
-
-  template<class FuncT, class N>
-  friend void Calculate(DominatorTreeBase<typename GraphTraits<N>::NodeType>& DT,
-                        FuncT& F);
-
-  /// updateDFSNumbers - Assign In and Out numbers to the nodes while walking
-  /// dominator tree in dfs order.
-  void updateDFSNumbers() {
-    unsigned DFSNum = 0;
-
-    SmallVector<std::pair<DomTreeNodeBase<NodeT>*,
-                typename DomTreeNodeBase<NodeT>::iterator>, 32> WorkStack;
-
-    DomTreeNodeBase<NodeT> *ThisRoot = getRootNode();
-
-    if (!ThisRoot)
-      return;
-
-    // Even in the case of multiple exits that form the post dominator root
-    // nodes, do not iterate over all exits, but start from the virtual root
-    // node. Otherwise bbs, that are not post dominated by any exit but by the
-    // virtual root node, will never be assigned a DFS number.
-    WorkStack.push_back(std::make_pair(ThisRoot, ThisRoot->begin()));
-    ThisRoot->DFSNumIn = DFSNum++;
-
-    while (!WorkStack.empty()) {
-      DomTreeNodeBase<NodeT> *Node = WorkStack.back().first;
-      typename DomTreeNodeBase<NodeT>::iterator ChildIt =
-        WorkStack.back().second;
-
-      // If we visited all of the children of this node, "recurse" back up the
-      // stack setting the DFOutNum.
-      if (ChildIt == Node->end()) {
-        Node->DFSNumOut = DFSNum++;
-        WorkStack.pop_back();
-      } else {
-        // Otherwise, recursively visit this child.
-        DomTreeNodeBase<NodeT> *Child = *ChildIt;
-        ++WorkStack.back().second;
-
-        WorkStack.push_back(std::make_pair(Child, Child->begin()));
-        Child->DFSNumIn = DFSNum++;
-      }
-    }
-
-    SlowQueries = 0;
-    DFSInfoValid = true;
-  }
-
-  DomTreeNodeBase<NodeT> *getNodeForBlock(NodeT *BB) {
-    if (DomTreeNodeBase<NodeT> *Node = getNode(BB))
-      return Node;
-
-    // Haven't calculated this node yet?  Get or calculate the node for the
-    // immediate dominator.
-    NodeT *IDom = getIDom(BB);
-
-    assert(IDom || this->DomTreeNodes[NULL]);
-    DomTreeNodeBase<NodeT> *IDomNode = getNodeForBlock(IDom);
-
-    // Add a new tree node for this BasicBlock, and link it as a child of
-    // IDomNode
-    DomTreeNodeBase<NodeT> *C = new DomTreeNodeBase<NodeT>(BB, IDomNode);
-    return this->DomTreeNodes[BB] = IDomNode->addChild(C);
-  }
-
-  inline NodeT *getIDom(NodeT *BB) const {
-    return IDoms.lookup(BB);
-  }
-
-  inline void addRoot(NodeT* BB) {
-    this->Roots.push_back(BB);
-  }
-
-public:
-  /// recalculate - compute a dominator tree for the given function
-  template<class FT>
-  void recalculate(FT& F) {
-    typedef GraphTraits<FT*> TraitsTy;
-    reset();
-    this->Vertex.push_back(0);
-
-    if (!this->IsPostDominators) {
-      // Initialize root
-      NodeT *entry = TraitsTy::getEntryNode(&F);
-      this->Roots.push_back(entry);
-      this->IDoms[entry] = 0;
-      this->DomTreeNodes[entry] = 0;
-
-      Calculate<FT, NodeT*>(*this, F);
-    } else {
-      // Initialize the roots list
-      for (typename TraitsTy::nodes_iterator I = TraitsTy::nodes_begin(&F),
-                                        E = TraitsTy::nodes_end(&F); I != E; ++I) {
-        if (TraitsTy::child_begin(I) == TraitsTy::child_end(I))
-          addRoot(I);
-
-        // Prepopulate maps so that we don't get iterator invalidation issues later.
-        this->IDoms[I] = 0;
-        this->DomTreeNodes[I] = 0;
-      }
-
-      Calculate<FT, Inverse<NodeT*> >(*this, F);
-    }
-  }
-};
-
-// These two functions are declared out of line as a workaround for building
-// with old (< r147295) versions of clang because of pr11642.
-template<class NodeT>
-bool DominatorTreeBase<NodeT>::dominates(const NodeT *A, const NodeT *B) {
-  if (A == B)
-    return true;
-
-  // Cast away the const qualifiers here. This is ok since
-  // this function doesn't actually return the values returned
-  // from getNode.
-  return dominates(getNode(const_cast<NodeT *>(A)),
-                   getNode(const_cast<NodeT *>(B)));
-}
-template<class NodeT>
-bool
-DominatorTreeBase<NodeT>::properlyDominates(const NodeT *A, const NodeT *B) {
-  if (A == B)
-    return false;
-
-  // Cast away the const qualifiers here. This is ok since
-  // this function doesn't actually return the values returned
-  // from getNode.
-  return dominates(getNode(const_cast<NodeT *>(A)),
-                   getNode(const_cast<NodeT *>(B)));
-}
-
-EXTERN_TEMPLATE_INSTANTIATION(class DominatorTreeBase<BasicBlock>);
-
 class BasicBlockEdge {
   const BasicBlock *Start;
   const BasicBlock *End;
diff --git a/include/llvm/IR/Verifier.h b/include/llvm/IR/Verifier.h
index 787166d4b57..7aec9732b9e 100644
--- a/include/llvm/IR/Verifier.h
+++ b/include/llvm/IR/Verifier.h
@@ -49,6 +49,11 @@ enum VerifierFailureAction {
 FunctionPass *
 createVerifierPass(VerifierFailureAction action = AbortProcessAction);
 
+/// \brief Check a function for errors, useful for use when debugging a
+/// pass.
+bool verifyFunction(const Function &F,
+                    VerifierFailureAction action = AbortProcessAction);
+
 /// \brief Check a module for errors.
 ///
 /// If there are no errors, the function returns false. If an error is found,
@@ -59,11 +64,6 @@ bool verifyModule(const Module &M,
                   VerifierFailureAction action = AbortProcessAction,
                   std::string *ErrorInfo = 0);
 
-/// \brief Check a function for errors, useful for use when debugging a
-/// pass.
-bool verifyFunction(const Function &F,
-                    VerifierFailureAction action = AbortProcessAction);
-
 } // End llvm namespace
 
 #endif
diff --git a/include/llvm/Support/GenericDomTree.h b/include/llvm/Support/GenericDomTree.h
new file mode 100644
index 00000000000..55dcb94635a
--- /dev/null
+++ b/include/llvm/Support/GenericDomTree.h
@@ -0,0 +1,718 @@
+//===- GenericDomTree.h - Generic dominator trees for graphs ----*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+/// \file
+///
+/// This file defines a set of templates that efficiently compute a dominator
+/// tree over a generic graph. This is used typically in LLVM for fast
+/// dominance queries on the CFG, but is fully generic w.r.t. the underlying
+/// graph types.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SUPPORT_GENERIC_DOM_TREE_H
+#define LLVM_SUPPORT_GENERIC_DOM_TREE_H
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/DepthFirstIterator.h"
+#include "llvm/ADT/GraphTraits.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/Support/CFG.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/raw_ostream.h"
+#include <algorithm>
+
+namespace llvm {
+
+//===----------------------------------------------------------------------===//
+/// DominatorBase - Base class that other, more interesting dominator analyses
+/// inherit from.
+///
+template <class NodeT>
+class DominatorBase {
+protected:
+  std::vector<NodeT*> Roots;
+  const bool IsPostDominators;
+  inline explicit DominatorBase(bool isPostDom) :
+    Roots(), IsPostDominators(isPostDom) {}
+public:
+
+  /// getRoots - Return the root blocks of the current CFG.  This may include
+  /// multiple blocks if we are computing post dominators.  For forward
+  /// dominators, this will always be a single block (the entry node).
+  ///
+  inline const std::vector<NodeT*> &getRoots() const { return Roots; }
+
+  /// isPostDominator - Returns true if analysis based of postdoms
+  ///
+  bool isPostDominator() const { return IsPostDominators; }
+};
+
+
+//===----------------------------------------------------------------------===//
+// DomTreeNodeBase - Dominator Tree Node
+template<class NodeT> class DominatorTreeBase;
+struct PostDominatorTree;
+
+template <class NodeT>
+class DomTreeNodeBase {
+  NodeT *TheBB;
+  DomTreeNodeBase<NodeT> *IDom;
+  std::vector<DomTreeNodeBase<NodeT> *> Children;
+  int DFSNumIn, DFSNumOut;
+
+  template<class N> friend class DominatorTreeBase;
+  friend struct PostDominatorTree;
+public:
+  typedef typename std::vector<DomTreeNodeBase<NodeT> *>::iterator iterator;
+  typedef typename std::vector<DomTreeNodeBase<NodeT> *>::const_iterator
+                   const_iterator;
+
+  iterator begin()             { return Children.begin(); }
+  iterator end()               { return Children.end(); }
+  const_iterator begin() const { return Children.begin(); }
+  const_iterator end()   const { return Children.end(); }
+
+  NodeT *getBlock() const { return TheBB; }
+  DomTreeNodeBase<NodeT> *getIDom() const { return IDom; }
+  const std::vector<DomTreeNodeBase<NodeT>*> &getChildren() const {
+    return Children;
+  }
+
+  DomTreeNodeBase(NodeT *BB, DomTreeNodeBase<NodeT> *iDom)
+    : TheBB(BB), IDom(iDom), DFSNumIn(-1), DFSNumOut(-1) { }
+
+  DomTreeNodeBase<NodeT> *addChild(DomTreeNodeBase<NodeT> *C) {
+    Children.push_back(C);
+    return C;
+  }
+
+  size_t getNumChildren() const {
+    return Children.size();
+  }
+
+  void clearAllChildren() {
+    Children.clear();
+  }
+
+  bool compare(const DomTreeNodeBase<NodeT> *Other) const {
+    if (getNumChildren() != Other->getNumChildren())
+      return true;
+
+    SmallPtrSet<const NodeT *, 4> OtherChildren;
+    for (const_iterator I = Other->begin(), E = Other->end(); I != E; ++I) {
+      const NodeT *Nd = (*I)->getBlock();
+      OtherChildren.insert(Nd);
+    }
+
+    for (const_iterator I = begin(), E = end(); I != E; ++I) {
+      const NodeT *N = (*I)->getBlock();
+      if (OtherChildren.count(N) == 0)
+        return true;
+    }
+    return false;
+  }
+
+  void setIDom(DomTreeNodeBase<NodeT> *NewIDom) {
+    assert(IDom && "No immediate dominator?");
+    if (IDom != NewIDom) {
+      typename std::vector<DomTreeNodeBase<NodeT>*>::iterator I =
+                  std::find(IDom->Children.begin(), IDom->Children.end(), this);
+      assert(I != IDom->Children.end() &&
+             "Not in immediate dominator children set!");
+      // I am no longer your child...
+      IDom->Children.erase(I);
+
+      // Switch to new dominator
+      IDom = NewIDom;
+      IDom->Children.push_back(this);
+    }
+  }
+
+  /// getDFSNumIn/getDFSNumOut - These are an internal implementation detail, do
+  /// not call them.
+  unsigned getDFSNumIn() const { return DFSNumIn; }
+  unsigned getDFSNumOut() const { return DFSNumOut; }
+private:
+  // Return true if this node is dominated by other. Use this only if DFS info
+  // is valid.
+  bool DominatedBy(const DomTreeNodeBase<NodeT> *other) const {
+    return this->DFSNumIn >= other->DFSNumIn &&
+      this->DFSNumOut <= other->DFSNumOut;
+  }
+};
+
+template<class NodeT>
+inline raw_ostream &operator<<(raw_ostream &o,
+                               const DomTreeNodeBase<NodeT> *Node) {
+  if (Node->getBlock())
+    Node->getBlock()->printAsOperand(o, false);
+  else
+    o << " <<exit node>>";
+
+  o << " {" << Node->getDFSNumIn() << "," << Node->getDFSNumOut() << "}";
+
+  return o << "\n";
+}
+
+template<class NodeT>
+inline void PrintDomTree(const DomTreeNodeBase<NodeT> *N, raw_ostream &o,
+                         unsigned Lev) {
+  o.indent(2*Lev) << "[" << Lev << "] " << N;
+  for (typename DomTreeNodeBase<NodeT>::const_iterator I = N->begin(),
+       E = N->end(); I != E; ++I)
+    PrintDomTree<NodeT>(*I, o, Lev+1);
+}
+
+//===----------------------------------------------------------------------===//
+/// DominatorTree - Calculate the immediate dominator tree for a function.
+///
+
+template<class FuncT, class N>
+void Calculate(DominatorTreeBase<typename GraphTraits<N>::NodeType>& DT,
+               FuncT& F);
+
+template<class NodeT>
+class DominatorTreeBase : public DominatorBase<NodeT> {
+  bool dominatedBySlowTreeWalk(const DomTreeNodeBase<NodeT> *A,
+                               const DomTreeNodeBase<NodeT> *B) const {
+    assert(A != B);
+    assert(isReachableFromEntry(B));
+    assert(isReachableFromEntry(A));
+
+    const DomTreeNodeBase<NodeT> *IDom;
+    while ((IDom = B->getIDom()) != 0 && IDom != A && IDom != B)
+      B = IDom;   // Walk up the tree
+    return IDom != 0;
+  }
+
+protected:
+  typedef DenseMap<NodeT*, DomTreeNodeBase<NodeT>*> DomTreeNodeMapType;
+  DomTreeNodeMapType DomTreeNodes;
+  DomTreeNodeBase<NodeT> *RootNode;
+
+  bool DFSInfoValid;
+  unsigned int SlowQueries;
+  // Information record used during immediate dominators computation.
+  struct InfoRec {
+    unsigned DFSNum;
+    unsigned Parent;
+    unsigned Semi;
+    NodeT *Label;
+
+    InfoRec() : DFSNum(0), Parent(0), Semi(0), Label(0) {}
+  };
+
+  DenseMap<NodeT*, NodeT*> IDoms;
+
+  // Vertex - Map the DFS number to the NodeT*
+  std::vector<NodeT*> Vertex;
+
+  // Info - Collection of information used during the computation of idoms.
+  DenseMap<NodeT*, InfoRec> Info;
+
+  void reset() {
+    for (typename DomTreeNodeMapType::iterator I = this->DomTreeNodes.begin(),
+           E = DomTreeNodes.end(); I != E; ++I)
+      delete I->second;
+    DomTreeNodes.clear();
+    IDoms.clear();
+    this->Roots.clear();
+    Vertex.clear();
+    RootNode = 0;
+  }
+
+  // NewBB is split and now it has one successor. Update dominator tree to
+  // reflect this change.
+  template<class N, class GraphT>
+  void Split(DominatorTreeBase<typename GraphT::NodeType>& DT,
+             typename GraphT::NodeType* NewBB) {
+    assert(std::distance(GraphT::child_begin(NewBB),
+                         GraphT::child_end(NewBB)) == 1 &&
+           "NewBB should have a single successor!");
+    typename GraphT::NodeType* NewBBSucc = *GraphT::child_begin(NewBB);
+
+    std::vector<typename GraphT::NodeType*> PredBlocks;
+    typedef GraphTraits<Inverse<N> > InvTraits;
+    for (typename InvTraits::ChildIteratorType PI =
+         InvTraits::child_begin(NewBB),
+         PE = InvTraits::child_end(NewBB); PI != PE; ++PI)
+      PredBlocks.push_back(*PI);
+
+    assert(!PredBlocks.empty() && "No predblocks?");
+
+    bool NewBBDominatesNewBBSucc = true;
+    for (typename InvTraits::ChildIteratorType PI =
+         InvTraits::child_begin(NewBBSucc),
+         E = InvTraits::child_end(NewBBSucc); PI != E; ++PI) {
+      typename InvTraits::NodeType *ND = *PI;
+      if (ND != NewBB && !DT.dominates(NewBBSucc, ND) &&
+          DT.isReachableFromEntry(ND)) {
+        NewBBDominatesNewBBSucc = false;
+        break;
+      }
+    }
+
+    // Find NewBB's immediate dominator and create new dominator tree node for
+    // NewBB.
+    NodeT *NewBBIDom = 0;
+    unsigned i = 0;
+    for (i = 0; i < PredBlocks.size(); ++i)
+      if (DT.isReachableFromEntry(PredBlocks[i])) {
+        NewBBIDom = PredBlocks[i];
+        break;
+      }
+
+    // It's possible that none of the predecessors of NewBB are reachable;
+    // in that case, NewBB itself is unreachable, so nothing needs to be
+    // changed.
+    if (!NewBBIDom)
+      return;
+
+    for (i = i + 1; i < PredBlocks.size(); ++i) {
+      if (DT.isReachableFromEntry(PredBlocks[i]))
+        NewBBIDom = DT.findNearestCommonDominator(NewBBIDom, PredBlocks[i]);
+    }
+
+    // Create the new dominator tree node... and set the idom of NewBB.
+    DomTreeNodeBase<NodeT> *NewBBNode = DT.addNewBlock(NewBB, NewBBIDom);
+
+    // If NewBB strictly dominates other blocks, then it is now the immediate
+    // dominator of NewBBSucc.  Update the dominator tree as appropriate.
+    if (NewBBDominatesNewBBSucc) {
+      DomTreeNodeBase<NodeT> *NewBBSuccNode = DT.getNode(NewBBSucc);
+      DT.changeImmediateDominator(NewBBSuccNode, NewBBNode);
+    }
+  }
+
+public:
+  explicit DominatorTreeBase(bool isPostDom)
+    : DominatorBase<NodeT>(isPostDom), DFSInfoValid(false), SlowQueries(0) {}
+  virtual ~DominatorTreeBase() { reset(); }
+
+  /// compare - Return false if the other dominator tree base matches this
+  /// dominator tree base. Otherwise return true.
+  bool compare(DominatorTreeBase &Other) const {
+
+    const DomTreeNodeMapType &OtherDomTreeNodes = Other.DomTreeNodes;
+    if (DomTreeNodes.size() != OtherDomTreeNodes.size())
+      return true;
+
+    for (typename DomTreeNodeMapType::const_iterator
+           I = this->DomTreeNodes.begin(),
+           E = this->DomTreeNodes.end(); I != E; ++I) {
+      NodeT *BB = I->first;
+      typename DomTreeNodeMapType::const_iterator OI = OtherDomTreeNodes.find(BB);
+      if (OI == OtherDomTreeNodes.end())
+        return true;
+
+      DomTreeNodeBase<NodeT>* MyNd = I->second;
+      DomTreeNodeBase<NodeT>* OtherNd = OI->second;
+
+      if (MyNd->compare(OtherNd))
+        return true;
+    }
+
+    return false;
+  }
+
+  virtual void releaseMemory() { reset(); }
+
+  /// getNode - return the (Post)DominatorTree node for the specified basic
+  /// block.  This is the same as using operator[] on this class.
+  ///
+  inline DomTreeNodeBase<NodeT> *getNode(NodeT *BB) const {
+    return DomTreeNodes.lookup(BB);
+  }
+
+  /// getRootNode - This returns the entry node for the CFG of the function.  If
+  /// this tree represents the post-dominance relations for a function, however,
+  /// this root may be a node with the block == NULL.  This is the case when
+  /// there are multiple exit nodes from a particular function.  Consumers of
+  /// post-dominance information must be capable of dealing with this
+  /// possibility.
+  ///
+  DomTreeNodeBase<NodeT> *getRootNode() { return RootNode; }
+  const DomTreeNodeBase<NodeT> *getRootNode() const { return RootNode; }
+
+  /// Get all nodes dominated by R, including R itself.
+  void getDescendants(NodeT *R, SmallVectorImpl<NodeT *> &Result) const {
+    Result.clear();
+    const DomTreeNodeBase<NodeT> *RN = getNode(R);
+    if (RN == NULL)
+      return; // If R is unreachable, it will not be present in the DOM tree.
+    SmallVector<const DomTreeNodeBase<NodeT> *, 8> WL;
+    WL.push_back(RN);
+
+    while (!WL.empty()) {
+      const DomTreeNodeBase<NodeT> *N = WL.pop_back_val();
+      Result.push_back(N->getBlock());
+      WL.append(N->begin(), N->end());
+    }
+  }
+
+  /// properlyDominates - Returns true iff A dominates B and A != B.
+  /// Note that this is not a constant time operation!
+  ///
+  bool properlyDominates(const DomTreeNodeBase<NodeT> *A,
+                         const DomTreeNodeBase<NodeT> *B) {
+    if (A == 0 || B == 0)
+      return false;
+    if (A == B)
+      return false;
+    return dominates(A, B);
+  }
+
+  bool properlyDominates(const NodeT *A, const NodeT *B);
+
+  /// isReachableFromEntry - Return true if A is dominated by the entry
+  /// block of the function containing it.
+  bool isReachableFromEntry(const NodeT* A) const {
+    assert(!this->isPostDominator() &&
+           "This is not implemented for post dominators");
+    return isReachableFromEntry(getNode(const_cast<NodeT *>(A)));
+  }
+
+  inline bool isReachableFromEntry(const DomTreeNodeBase<NodeT> *A) const {
+    return A;
+  }
+
+  /// dominates - Returns true iff A dominates B.  Note that this is not a
+  /// constant time operation!
+  ///
+  inline bool dominates(const DomTreeNodeBase<NodeT> *A,
+                        const DomTreeNodeBase<NodeT> *B) {
+    // A node trivially dominates itself.
+    if (B == A)
+      return true;
+
+    // An unreachable node is dominated by anything.
+    if (!isReachableFromEntry(B))
+      return true;
+
+    // And dominates nothing.
+    if (!isReachableFromEntry(A))
+      return false;
+
+    // Compare the result of the tree walk and the dfs numbers, if expensive
+    // checks are enabled.
+#ifdef XDEBUG
+    assert((!DFSInfoValid ||
+            (dominatedBySlowTreeWalk(A, B) == B->DominatedBy(A))) &&
+           "Tree walk disagrees with dfs numbers!");
+#endif
+
+    if (DFSInfoValid)
+      return B->DominatedBy(A);
+
+    // If we end up with too many slow queries, just update the
+    // DFS numbers on the theory that we are going to keep querying.
+    SlowQueries++;
+    if (SlowQueries > 32) {
+      updateDFSNumbers();
+      return B->DominatedBy(A);
+    }
+
+    return dominatedBySlowTreeWalk(A, B);
+  }
+
+  bool dominates(const NodeT *A, const NodeT *B);
+
+  NodeT *getRoot() const {
+    assert(this->Roots.size() == 1 && "Should always have entry node!");
+    return this->Roots[0];
+  }
+
+  /// findNearestCommonDominator - Find nearest common dominator basic block
+  /// for basic block A and B. If there is no such block then return NULL.
+  NodeT *findNearestCommonDominator(NodeT *A, NodeT *B) {
+    assert(A->getParent() == B->getParent() &&
+           "Two blocks are not in same function");
+
+    // If either A or B is a entry block then it is nearest common dominator
+    // (for forward-dominators).
+    if (!this->isPostDominator()) {
+      NodeT &Entry = A->getParent()->front();
+      if (A == &Entry || B == &Entry)
+        return &Entry;
+    }
+
+    // If B dominates A then B is nearest common dominator.
+    if (dominates(B, A))
+      return B;
+
+    // If A dominates B then A is nearest common dominator.
+    if (dominates(A, B))
+      return A;
+
+    DomTreeNodeBase<NodeT> *NodeA = getNode(A);
+    DomTreeNodeBase<NodeT> *NodeB = getNode(B);
+
+    // Collect NodeA dominators set.
+    SmallPtrSet<DomTreeNodeBase<NodeT>*, 16> NodeADoms;
+    NodeADoms.insert(NodeA);
+    DomTreeNodeBase<NodeT> *IDomA = NodeA->getIDom();
+    while (IDomA) {
+      NodeADoms.insert(IDomA);
+      IDomA = IDomA->getIDom();
+    }
+
+    // Walk NodeB immediate dominators chain and find common dominator node.
+    DomTreeNodeBase<NodeT> *IDomB = NodeB->getIDom();
+    while (IDomB) {
+      if (NodeADoms.count(IDomB) != 0)
+        return IDomB->getBlock();
+
+      IDomB = IDomB->getIDom();
+    }
+
+    return NULL;
+  }
+
+  const NodeT *findNearestCommonDominator(const NodeT *A, const NodeT *B) {
+    // Cast away the const qualifiers here. This is ok since
+    // const is re-introduced on the return type.
+    return findNearestCommonDominator(const_cast<NodeT *>(A),
+                                      const_cast<NodeT *>(B));
+  }
+
+  //===--------------------------------------------------------------------===//
+  // API to update (Post)DominatorTree information based on modifications to
+  // the CFG...
+
+  /// addNewBlock - Add a new node to the dominator tree information.  This
+  /// creates a new node as a child of DomBB dominator node,linking it into
+  /// the children list of the immediate dominator.
+  DomTreeNodeBase<NodeT> *addNewBlock(NodeT *BB, NodeT *DomBB) {
+    assert(getNode(BB) == 0 && "Block already in dominator tree!");
+    DomTreeNodeBase<NodeT> *IDomNode = getNode(DomBB);
+    assert(IDomNode && "Not immediate dominator specified for block!");
+    DFSInfoValid = false;
+    return DomTreeNodes[BB] =
+      IDomNode->addChild(new DomTreeNodeBase<NodeT>(BB, IDomNode));
+  }
+
+  /// changeImmediateDominator - This method is used to update the dominator
+  /// tree information when a node's immediate dominator changes.
+  ///
+  void changeImmediateDominator(DomTreeNodeBase<NodeT> *N,
+                                DomTreeNodeBase<NodeT> *NewIDom) {
+    assert(N && NewIDom && "Cannot change null node pointers!");
+    DFSInfoValid = false;
+    N->setIDom(NewIDom);
+  }
+
+  void changeImmediateDominator(NodeT *BB, NodeT *NewBB) {
+    changeImmediateDominator(getNode(BB), getNode(NewBB));
+  }
+
+  /// eraseNode - Removes a node from the dominator tree. Block must not
+  /// dominate any other blocks. Removes node from its immediate dominator's
+  /// children list. Deletes dominator node associated with basic block BB.
+  void eraseNode(NodeT *BB) {
+    DomTreeNodeBase<NodeT> *Node = getNode(BB);
+    assert(Node && "Removing node that isn't in dominator tree.");
+    assert(Node->getChildren().empty() && "Node is not a leaf node.");
+
+      // Remove node from immediate dominator's children list.
+    DomTreeNodeBase<NodeT> *IDom = Node->getIDom();
+    if (IDom) {
+      typename std::vector<DomTreeNodeBase<NodeT>*>::iterator I =
+        std::find(IDom->Children.begin(), IDom->Children.end(), Node);
+      assert(I != IDom->Children.end() &&
+             "Not in immediate dominator children set!");
+      // I am no longer your child...
+      IDom->Children.erase(I);
+    }
+
+    DomTreeNodes.erase(BB);
+    delete Node;
+  }
+
+  /// removeNode - Removes a node from the dominator tree.  Block must not
+  /// dominate any other blocks.  Invalidates any node pointing to removed
+  /// block.
+  void removeNode(NodeT *BB) {
+    assert(getNode(BB) && "Removing node that isn't in dominator tree.");
+    DomTreeNodes.erase(BB);
+  }
+
+  /// splitBlock - BB is split and now it has one successor. Update dominator
+  /// tree to reflect this change.
+  void splitBlock(NodeT* NewBB) {
+    if (this->IsPostDominators)
+      this->Split<Inverse<NodeT*>, GraphTraits<Inverse<NodeT*> > >(*this, NewBB);
+    else
+      this->Split<NodeT*, GraphTraits<NodeT*> >(*this, NewBB);
+  }
+
+  /// print - Convert to human readable form
+  ///
+  void print(raw_ostream &o) const {
+    o << "=============================--------------------------------\n";
+    if (this->isPostDominator())
+      o << "Inorder PostDominator Tree: ";
+    else
+      o << "Inorder Dominator Tree: ";
+    if (!this->DFSInfoValid)
+      o << "DFSNumbers invalid: " << SlowQueries << " slow queries.";
+    o << "\n";
+
+    // The postdom tree can have a null root if there are no returns.
+    if (getRootNode())
+      PrintDomTree<NodeT>(getRootNode(), o, 1);
+  }
+
+protected:
+  template<class GraphT>
+  friend typename GraphT::NodeType* Eval(
+                               DominatorTreeBase<typename GraphT::NodeType>& DT,
+                                         typename GraphT::NodeType* V,
+                                         unsigned LastLinked);
+
+  template<class GraphT>
+  friend unsigned DFSPass(DominatorTreeBase<typename GraphT::NodeType>& DT,
+                          typename GraphT::NodeType* V,
+                          unsigned N);
+
+  template<class FuncT, class N>
+  friend void Calculate(DominatorTreeBase<typename GraphTraits<N>::NodeType>& DT,
+                        FuncT& F);
+
+  /// updateDFSNumbers - Assign In and Out numbers to the nodes while walking
+  /// dominator tree in dfs order.
+  void updateDFSNumbers() {
+    unsigned DFSNum = 0;
+
+    SmallVector<std::pair<DomTreeNodeBase<NodeT>*,
+                typename DomTreeNodeBase<NodeT>::iterator>, 32> WorkStack;
+
+    DomTreeNodeBase<NodeT> *ThisRoot = getRootNode();
+
+    if (!ThisRoot)
+      return;
+
+    // Even in the case of multiple exits that form the post dominator root
+    // nodes, do not iterate over all exits, but start from the virtual root
+    // node. Otherwise bbs, that are not post dominated by any exit but by the
+    // virtual root node, will never be assigned a DFS number.
+    WorkStack.push_back(std::make_pair(ThisRoot, ThisRoot->begin()));
+    ThisRoot->DFSNumIn = DFSNum++;
+
+    while (!WorkStack.empty()) {
+      DomTreeNodeBase<NodeT> *Node = WorkStack.back().first;
+      typename DomTreeNodeBase<NodeT>::iterator ChildIt =
+        WorkStack.back().second;
+
+      // If we visited all of the children of this node, "recurse" back up the
+      // stack setting the DFOutNum.
+      if (ChildIt == Node->end()) {
+        Node->DFSNumOut = DFSNum++;
+        WorkStack.pop_back();
+      } else {
+        // Otherwise, recursively visit this child.
+        DomTreeNodeBase<NodeT> *Child = *ChildIt;
+        ++WorkStack.back().second;
+
+        WorkStack.push_back(std::make_pair(Child, Child->begin()));
+        Child->DFSNumIn = DFSNum++;
+      }
+    }
+
+    SlowQueries = 0;
+    DFSInfoValid = true;
+  }
+
+  DomTreeNodeBase<NodeT> *getNodeForBlock(NodeT *BB) {
+    if (DomTreeNodeBase<NodeT> *Node = getNode(BB))
+      return Node;
+
+    // Haven't calculated this node yet?  Get or calculate the node for the
+    // immediate dominator.
+    NodeT *IDom = getIDom(BB);
+
+    assert(IDom || this->DomTreeNodes[NULL]);
+    DomTreeNodeBase<NodeT> *IDomNode = getNodeForBlock(IDom);
+
+    // Add a new tree node for this NodeT, and link it as a child of
+    // IDomNode
+    DomTreeNodeBase<NodeT> *C = new DomTreeNodeBase<NodeT>(BB, IDomNode);
+    return this->DomTreeNodes[BB] = IDomNode->addChild(C);
+  }
+
+  inline NodeT *getIDom(NodeT *BB) const {
+    return IDoms.lookup(BB);
+  }
+
+  inline void addRoot(NodeT* BB) {
+    this->Roots.push_back(BB);
+  }
+
+public:
+  /// recalculate - compute a dominator tree for the given function
+  template<class FT>
+  void recalculate(FT& F) {
+    typedef GraphTraits<FT*> TraitsTy;
+    reset();
+    this->Vertex.push_back(0);
+
+    if (!this->IsPostDominators) {
+      // Initialize root
+      NodeT *entry = TraitsTy::getEntryNode(&F);
+      this->Roots.push_back(entry);
+      this->IDoms[entry] = 0;
+      this->DomTreeNodes[entry] = 0;
+
+      Calculate<FT, NodeT*>(*this, F);
+    } else {
+      // Initialize the roots list
+      for (typename TraitsTy::nodes_iterator I = TraitsTy::nodes_begin(&F),
+                                        E = TraitsTy::nodes_end(&F); I != E; ++I) {
+        if (TraitsTy::child_begin(I) == TraitsTy::child_end(I))
+          addRoot(I);
+
+        // Prepopulate maps so that we don't get iterator invalidation issues later.
+        this->IDoms[I] = 0;
+        this->DomTreeNodes[I] = 0;
+      }
+
+      Calculate<FT, Inverse<NodeT*> >(*this, F);
+    }
+  }
+};
+
+// These two functions are declared out of line as a workaround for building
+// with old (< r147295) versions of clang because of pr11642.
+template<class NodeT>
+bool DominatorTreeBase<NodeT>::dominates(const NodeT *A, const NodeT *B) {
+  if (A == B)
+    return true;
+
+  // Cast away the const qualifiers here. This is ok since
+  // this function doesn't actually return the values returned
+  // from getNode.
+  return dominates(getNode(const_cast<NodeT *>(A)),
+                   getNode(const_cast<NodeT *>(B)));
+}
+template<class NodeT>
+bool
+DominatorTreeBase<NodeT>::properlyDominates(const NodeT *A, const NodeT *B) {
+  if (A == B)
+    return false;
+
+  // Cast away the const qualifiers here. This is ok since
+  // this function doesn't actually return the values returned
+  // from getNode.
+  return dominates(getNode(const_cast<NodeT *>(A)),
+                   getNode(const_cast<NodeT *>(B)));
+}
+
+}
+
+#endif
diff --git a/include/llvm/IR/DominatorInternals.h b/include/llvm/Support/GenericDomTreeConstruction.h
similarity index 92%
rename from include/llvm/IR/DominatorInternals.h
rename to include/llvm/Support/GenericDomTreeConstruction.h
index 9e2922d3086..a0b444e7b9c 100644
--- a/include/llvm/IR/DominatorInternals.h
+++ b/include/llvm/Support/GenericDomTreeConstruction.h
@@ -1,4 +1,4 @@
-//===- DominatorInternals.h - Dominator Calculation --------------*- C++ -*-==//
+//===- GenericDomTreeConstruction.h - Dominator Calculation ------*- C++ -*-==//
 //
 //                     The LLVM Compiler Infrastructure
 //
@@ -6,27 +6,27 @@
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
+/// \file
+///
+/// Generic dominator tree construction - This file provides rouitens to
+/// constructs immediate dominator information for a flow-graph based on the
+/// algorithm described in this document:
+///
+///   A Fast Algorithm for Finding Dominators in a Flowgraph
+///   T. Lengauer & R. Tarjan, ACM TOPLAS July 1979, pgs 121-141.
+///
+/// This implements the O(n*log(n)) versions of EVAL and LINK, because it turns
+/// out that the theoretically slower O(n*log(n)) implementation is actually
+/// faster than the almost-linear O(n*alpha(n)) version, even for large CFGs.
+///
+//===----------------------------------------------------------------------===//
 
-#ifndef LLVM_IR_DOMINATOR_INTERNALS_H
-#define LLVM_IR_DOMINATOR_INTERNALS_H
+
+#ifndef LLVM_SUPPORT_GENERIC_DOM_TREE_CONSTRUCTION_H
+#define LLVM_SUPPORT_GENERIC_DOM_TREE_CONSTRUCTION_H
 
 #include "llvm/ADT/SmallPtrSet.h"
-#include "llvm/IR/Dominators.h"
-
-//===----------------------------------------------------------------------===//
-//
-// DominatorTree construction - This pass constructs immediate dominator
-// information for a flow-graph based on the algorithm described in this
-// document:
-//
-//   A Fast Algorithm for Finding Dominators in a Flowgraph
-//   T. Lengauer & R. Tarjan, ACM TOPLAS July 1979, pgs 121-141.
-//
-// This implements the O(n*log(n)) versions of EVAL and LINK, because it turns
-// out that the theoretically slower O(n*log(n)) implementation is actually
-// faster than the almost-linear O(n*alpha(n)) version, even for large CFGs.
-//
-//===----------------------------------------------------------------------===//
+#include "llvm/Support/GenericDomTree.h"
 
 namespace llvm {
 
diff --git a/lib/Analysis/PostDominators.cpp b/lib/Analysis/PostDominators.cpp
index 882c9ffc131..7da8f46ea10 100644
--- a/lib/Analysis/PostDominators.cpp
+++ b/lib/Analysis/PostDominators.cpp
@@ -16,7 +16,7 @@
 #include "llvm/Analysis/PostDominators.h"
 #include "llvm/ADT/DepthFirstIterator.h"
 #include "llvm/ADT/SetOperations.h"
-#include "llvm/IR/DominatorInternals.h"
+#include "llvm/Support/GenericDomTreeConstruction.h"
 #include "llvm/IR/Instructions.h"
 #include "llvm/Support/CFG.h"
 #include "llvm/Support/Debug.h"
diff --git a/lib/CodeGen/GCStrategy.cpp b/lib/CodeGen/GCStrategy.cpp
index 8bb6f1614a2..ca715dfe186 100644
--- a/lib/CodeGen/GCStrategy.cpp
+++ b/lib/CodeGen/GCStrategy.cpp
@@ -21,7 +21,6 @@
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/CodeGen/MachineModuleInfo.h"
 #include "llvm/CodeGen/Passes.h"
-#include "llvm/IR/DominatorInternals.h"
 #include "llvm/IR/Dominators.h"
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/IR/Module.h"
diff --git a/lib/IR/Dominators.cpp b/lib/IR/Dominators.cpp
index b5553626cf4..c831c19517f 100644
--- a/lib/IR/Dominators.cpp
+++ b/lib/IR/Dominators.cpp
@@ -18,12 +18,12 @@
 #include "llvm/ADT/DepthFirstIterator.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SmallVector.h"
-#include "llvm/IR/DominatorInternals.h"
 #include "llvm/IR/Instructions.h"
 #include "llvm/Support/CFG.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/Debug.h"
+#include "llvm/Support/GenericDomTreeConstruction.h"
 #include "llvm/Support/raw_ostream.h"
 #include <algorithm>
 using namespace llvm;
@@ -56,7 +56,8 @@ bool BasicBlockEdge::isSingleEdge() const {
 //===----------------------------------------------------------------------===//
 //
 // Provide public access to DominatorTree information.  Implementation details
-// can be found in DominatorInternals.h.
+// can be found in Dominators.h, GenericDomTree.h, and
+// GenericDomTreeConstruction.h.
 //
 //===----------------------------------------------------------------------===//
 
diff --git a/lib/Target/R600/AMDILCFGStructurizer.cpp b/lib/Target/R600/AMDILCFGStructurizer.cpp
index 84a5a451468..4ad7eba36e2 100644
--- a/lib/Target/R600/AMDILCFGStructurizer.cpp
+++ b/lib/Target/R600/AMDILCFGStructurizer.cpp
@@ -26,7 +26,6 @@
 #include "llvm/CodeGen/MachineLoopInfo.h"
 #include "llvm/CodeGen/MachinePostDominators.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
-#include "llvm/IR/DominatorInternals.h"
 #include "llvm/IR/Dominators.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
diff --git a/lib/Transforms/Scalar/CodeGenPrepare.cpp b/lib/Transforms/Scalar/CodeGenPrepare.cpp
index f0df1d44371..dcb5dae69e6 100644
--- a/lib/Transforms/Scalar/CodeGenPrepare.cpp
+++ b/lib/Transforms/Scalar/CodeGenPrepare.cpp
@@ -23,7 +23,6 @@
 #include "llvm/IR/Constants.h"
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/DerivedTypes.h"
-#include "llvm/IR/DominatorInternals.h"
 #include "llvm/IR/Dominators.h"
 #include "llvm/IR/Function.h"
 #include "llvm/IR/IRBuilder.h"