diff --git a/lib/CodeGen/MachineBasicBlock.cpp b/lib/CodeGen/MachineBasicBlock.cpp
new file mode 100644
index 0000000..ba428c5
--- /dev/null
+++ b/lib/CodeGen/MachineBasicBlock.cpp
@@ -0,0 +1,287 @@
+//===-- llvm/CodeGen/MachineBasicBlock.cpp ----------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Collect the sequence of machine instructions for a basic block.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/BasicBlock.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/Target/MRegisterInfo.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Support/LeakDetector.h"
+#include <algorithm>
+using namespace llvm;
+
+MachineBasicBlock::~MachineBasicBlock() {
+  LeakDetector::removeGarbageObject(this);
+}
+
+std::ostream& llvm::operator<<(std::ostream &OS, const MachineBasicBlock &MBB) {
+  MBB.print(OS);
+  return OS;
+}
+
+// MBBs start out as #-1. When a MBB is added to a MachineFunction, it
+// gets the next available unique MBB number. If it is removed from a
+// MachineFunction, it goes back to being #-1.
+void ilist_traits<MachineBasicBlock>::addNodeToList(MachineBasicBlock* N) {
+  assert(N->Parent == 0 && "machine instruction already in a basic block");
+  N->Parent = Parent;
+  N->Number = Parent->addToMBBNumbering(N);
+  LeakDetector::removeGarbageObject(N);
+}
+
+void ilist_traits<MachineBasicBlock>::removeNodeFromList(MachineBasicBlock* N) {
+  assert(N->Parent != 0 && "machine instruction not in a basic block");
+  N->Parent->removeFromMBBNumbering(N->Number);
+  N->Number = -1;
+  N->Parent = 0;
+  LeakDetector::addGarbageObject(N);
+}
+
+
+MachineInstr* ilist_traits<MachineInstr>::createSentinel() {
+  MachineInstr* dummy = new MachineInstr();
+  LeakDetector::removeGarbageObject(dummy);
+  return dummy;
+}
+
+void ilist_traits<MachineInstr>::addNodeToList(MachineInstr* N) {
+  assert(N->parent == 0 && "machine instruction already in a basic block");
+  N->parent = parent;
+  LeakDetector::removeGarbageObject(N);
+}
+
+void ilist_traits<MachineInstr>::removeNodeFromList(MachineInstr* N) {
+  assert(N->parent != 0 && "machine instruction not in a basic block");
+  N->parent = 0;
+  LeakDetector::addGarbageObject(N);
+}
+
+void ilist_traits<MachineInstr>::transferNodesFromList(
+  iplist<MachineInstr, ilist_traits<MachineInstr> >& fromList,
+  ilist_iterator<MachineInstr> first,
+  ilist_iterator<MachineInstr> last) {
+  if (parent != fromList.parent)
+    for (; first != last; ++first)
+      first->parent = parent;
+}
+
+MachineBasicBlock::iterator MachineBasicBlock::getFirstTerminator() {
+  const TargetInstrInfo& TII = *getParent()->getTarget().getInstrInfo();
+  iterator I = end();
+  while (I != begin() && TII.isTerminatorInstr((--I)->getOpcode()));
+  if (I != end() && !TII.isTerminatorInstr(I->getOpcode())) ++I;
+  return I;
+}
+
+void MachineBasicBlock::dump() const {
+  print(*cerr.stream());
+}
+
+static inline void OutputReg(std::ostream &os, unsigned RegNo,
+                             const MRegisterInfo *MRI = 0) {
+  if (!RegNo || MRegisterInfo::isPhysicalRegister(RegNo)) {
+    if (MRI)
+      os << " %" << MRI->get(RegNo).Name;
+    else
+      os << " %mreg(" << RegNo << ")";
+  } else
+    os << " %reg" << RegNo;
+}
+
+void MachineBasicBlock::print(std::ostream &OS) const {
+  const MachineFunction *MF = getParent();
+  if(!MF) {
+    OS << "Can't print out MachineBasicBlock because parent MachineFunction"
+       << " is null\n";
+    return;
+  }
+
+  const BasicBlock *LBB = getBasicBlock();
+  OS << "\n";
+  if (LBB) OS << LBB->getName() << ": ";
+  OS << (const void*)this
+     << ", LLVM BB @" << (const void*) LBB << ", ID#" << getNumber();
+  if (isLandingPad()) OS << ", EH LANDING PAD";
+  OS << ":\n";
+
+  const MRegisterInfo *MRI = MF->getTarget().getRegisterInfo();  
+  if (livein_begin() != livein_end()) {
+    OS << "Live Ins:";
+    for (const_livein_iterator I = livein_begin(),E = livein_end(); I != E; ++I)
+      OutputReg(OS, *I, MRI);
+    OS << "\n";
+  }
+  // Print the preds of this block according to the CFG.
+  if (!pred_empty()) {
+    OS << "    Predecessors according to CFG:";
+    for (const_pred_iterator PI = pred_begin(), E = pred_end(); PI != E; ++PI)
+      OS << " " << *PI << " (#" << (*PI)->getNumber() << ")";
+    OS << "\n";
+  }
+  
+  for (const_iterator I = begin(); I != end(); ++I) {
+    OS << "\t";
+    I->print(OS, &getParent()->getTarget());
+  }
+
+  // Print the successors of this block according to the CFG.
+  if (!succ_empty()) {
+    OS << "    Successors according to CFG:";
+    for (const_succ_iterator SI = succ_begin(), E = succ_end(); SI != E; ++SI)
+      OS << " " << *SI << " (#" << (*SI)->getNumber() << ")";
+    OS << "\n";
+  }
+}
+
+void MachineBasicBlock::removeLiveIn(unsigned Reg) {
+  livein_iterator I = std::find(livein_begin(), livein_end(), Reg);
+  assert(I != livein_end() && "Not a live in!");
+  LiveIns.erase(I);
+}
+
+void MachineBasicBlock::moveBefore(MachineBasicBlock *NewAfter) {
+  MachineFunction::BasicBlockListType &BBList =getParent()->getBasicBlockList();
+  getParent()->getBasicBlockList().splice(NewAfter, BBList, this);
+}
+
+void MachineBasicBlock::moveAfter(MachineBasicBlock *NewBefore) {
+  MachineFunction::BasicBlockListType &BBList =getParent()->getBasicBlockList();
+  MachineFunction::iterator BBI = NewBefore;
+  getParent()->getBasicBlockList().splice(++BBI, BBList, this);
+}
+
+
+void MachineBasicBlock::addSuccessor(MachineBasicBlock *succ) {
+  Successors.push_back(succ);
+  succ->addPredecessor(this);
+}
+
+void MachineBasicBlock::removeSuccessor(MachineBasicBlock *succ) {
+  succ->removePredecessor(this);
+  succ_iterator I = std::find(Successors.begin(), Successors.end(), succ);
+  assert(I != Successors.end() && "Not a current successor!");
+  Successors.erase(I);
+}
+
+MachineBasicBlock::succ_iterator MachineBasicBlock::removeSuccessor(succ_iterator I) {
+  assert(I != Successors.end() && "Not a current successor!");
+  (*I)->removePredecessor(this);
+  return(Successors.erase(I));
+}
+
+void MachineBasicBlock::addPredecessor(MachineBasicBlock *pred) {
+  Predecessors.push_back(pred);
+}
+
+void MachineBasicBlock::removePredecessor(MachineBasicBlock *pred) {
+  std::vector<MachineBasicBlock *>::iterator I =
+    std::find(Predecessors.begin(), Predecessors.end(), pred);
+  assert(I != Predecessors.end() && "Pred is not a predecessor of this block!");
+  Predecessors.erase(I);
+}
+
+bool MachineBasicBlock::isSuccessor(MachineBasicBlock *MBB) const {
+  std::vector<MachineBasicBlock *>::const_iterator I =
+    std::find(Successors.begin(), Successors.end(), MBB);
+  return I != Successors.end();
+}
+
+/// ReplaceUsesOfBlockWith - Given a machine basic block that branched to
+/// 'Old', change the code and CFG so that it branches to 'New' instead.
+void MachineBasicBlock::ReplaceUsesOfBlockWith(MachineBasicBlock *Old,
+                                               MachineBasicBlock *New) {
+  assert(Old != New && "Cannot replace self with self!");
+
+  MachineBasicBlock::iterator I = end();
+  while (I != begin()) {
+    --I;
+    if (!(I->getInstrDescriptor()->Flags & M_TERMINATOR_FLAG)) break;
+
+    // Scan the operands of this machine instruction, replacing any uses of Old
+    // with New.
+    for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i)
+      if (I->getOperand(i).isMachineBasicBlock() &&
+          I->getOperand(i).getMachineBasicBlock() == Old)
+        I->getOperand(i).setMachineBasicBlock(New);
+  }
+
+  // Update the successor information.  If New was already a successor, just
+  // remove the link to Old instead of creating another one.  PR 1444.
+  removeSuccessor(Old);
+  if (!isSuccessor(New))
+    addSuccessor(New);
+}
+
+/// CorrectExtraCFGEdges - Various pieces of code can cause excess edges in the
+/// CFG to be inserted.  If we have proven that MBB can only branch to DestA and
+/// DestB, remove any other MBB successors from the CFG.  DestA and DestB can
+/// be null.
+/// Besides DestA and DestB, retain other edges leading to LandingPads (currently
+/// there can be only one; we don't check or require that here).
+/// Note it is possible that DestA and/or DestB are LandingPads.
+bool MachineBasicBlock::CorrectExtraCFGEdges(MachineBasicBlock *DestA,
+                                             MachineBasicBlock *DestB,
+                                             bool isCond) {
+  bool MadeChange = false;
+  bool AddedFallThrough = false;
+
+  MachineBasicBlock *FallThru = getNext();
+  
+  // If this block ends with a conditional branch that falls through to its
+  // successor, set DestB as the successor.
+  if (isCond) {
+    if (DestB == 0 && FallThru != getParent()->end()) {
+      DestB = FallThru;
+      AddedFallThrough = true;
+    }
+  } else {
+    // If this is an unconditional branch with no explicit dest, it must just be
+    // a fallthrough into DestB.
+    if (DestA == 0 && FallThru != getParent()->end()) {
+      DestA = FallThru;
+      AddedFallThrough = true;
+    }
+  }
+  
+  MachineBasicBlock::succ_iterator SI = succ_begin();
+  MachineBasicBlock *OrigDestA = DestA, *OrigDestB = DestB;
+  while (SI != succ_end()) {
+    if (*SI == DestA && DestA == DestB) {
+      DestA = DestB = 0;
+      ++SI;
+    } else if (*SI == DestA) {
+      DestA = 0;
+      ++SI;
+    } else if (*SI == DestB) {
+      DestB = 0;
+      ++SI;
+    } else if ((*SI)->isLandingPad() && 
+               *SI!=OrigDestA && *SI!=OrigDestB) {
+      ++SI;
+    } else {
+      // Otherwise, this is a superfluous edge, remove it.
+      SI = removeSuccessor(SI);
+      MadeChange = true;
+    }
+  }
+  if (!AddedFallThrough) {
+    assert(DestA == 0 && DestB == 0 &&
+           "MachineCFG is missing edges!");
+  } else if (isCond) {
+    assert(DestA == 0 && "MachineCFG is missing edges!");
+  }
+  return MadeChange;
+}