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diff --git a/contrib/llvm/lib/CodeGen/MachineBranchProbabilityInfo.cpp b/contrib/llvm/lib/CodeGen/MachineBranchProbabilityInfo.cpp
new file mode 100644
index 0000000..cf6d401
--- /dev/null
+++ b/contrib/llvm/lib/CodeGen/MachineBranchProbabilityInfo.cpp
@@ -0,0 +1,83 @@
+//===- MachineBranchProbabilityInfo.cpp - Machine Branch Probability Info -===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This analysis uses probability info stored in Machine Basic Blocks.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/MachineBranchProbabilityInfo.h"
+#include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace llvm;
+
+INITIALIZE_PASS_BEGIN(MachineBranchProbabilityInfo, "machine-branch-prob",
+                      "Machine Branch Probability Analysis", false, true)
+INITIALIZE_PASS_END(MachineBranchProbabilityInfo, "machine-branch-prob",
+                    "Machine Branch Probability Analysis", false, true)
+
+char MachineBranchProbabilityInfo::ID = 0;
+
+void MachineBranchProbabilityInfo::anchor() { }
+
+BranchProbability MachineBranchProbabilityInfo::getEdgeProbability(
+    const MachineBasicBlock *Src,
+    MachineBasicBlock::const_succ_iterator Dst) const {
+  return Src->getSuccProbability(Dst);
+}
+
+BranchProbability MachineBranchProbabilityInfo::getEdgeProbability(
+    const MachineBasicBlock *Src, const MachineBasicBlock *Dst) const {
+  // This is a linear search. Try to use the const_succ_iterator version when
+  // possible.
+  return getEdgeProbability(Src,
+                            std::find(Src->succ_begin(), Src->succ_end(), Dst));
+}
+
+bool
+MachineBranchProbabilityInfo::isEdgeHot(const MachineBasicBlock *Src,
+                                        const MachineBasicBlock *Dst) const {
+  // Hot probability is at least 4/5 = 80%
+  static BranchProbability HotProb(4, 5);
+  return getEdgeProbability(Src, Dst) > HotProb;
+}
+
+MachineBasicBlock *
+MachineBranchProbabilityInfo::getHotSucc(MachineBasicBlock *MBB) const {
+  auto MaxProb = BranchProbability::getZero();
+  MachineBasicBlock *MaxSucc = nullptr;
+  for (MachineBasicBlock::const_succ_iterator I = MBB->succ_begin(),
+       E = MBB->succ_end(); I != E; ++I) {
+    auto Prob = getEdgeProbability(MBB, I);
+    if (Prob > MaxProb) {
+      MaxProb = Prob;
+      MaxSucc = *I;
+    }
+  }
+
+  static BranchProbability HotProb(4, 5);
+  if (getEdgeProbability(MBB, MaxSucc) >= HotProb)
+    return MaxSucc;
+
+  return nullptr;
+}
+
+raw_ostream &MachineBranchProbabilityInfo::printEdgeProbability(
+    raw_ostream &OS, const MachineBasicBlock *Src,
+    const MachineBasicBlock *Dst) const {
+
+  const BranchProbability Prob = getEdgeProbability(Src, Dst);
+  OS << "edge MBB#" << Src->getNumber() << " -> MBB#" << Dst->getNumber()
+     << " probability is " << Prob
+     << (isEdgeHot(Src, Dst) ? " [HOT edge]\n" : "\n");
+
+  return OS;
+}