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diff --git a/contrib/llvm/lib/CodeGen/PHIElimination.h b/contrib/llvm/lib/CodeGen/PHIElimination.h
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+//===-- lib/CodeGen/PHIElimination.h ----------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_PHIELIMINATION_HPP
+#define LLVM_CODEGEN_PHIELIMINATION_HPP
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+
+namespace llvm {
+  class LiveVariables;
+  
+  /// Lower PHI instructions to copies.  
+  class PHIElimination : public MachineFunctionPass {
+    MachineRegisterInfo  *MRI; // Machine register information
+
+  public:
+    static char ID; // Pass identification, replacement for typeid
+    PHIElimination() : MachineFunctionPass(&ID) {}
+
+    virtual bool runOnMachineFunction(MachineFunction &Fn);
+    
+    virtual void getAnalysisUsage(AnalysisUsage &AU) const;
+
+  private:
+    /// EliminatePHINodes - Eliminate phi nodes by inserting copy instructions
+    /// in predecessor basic blocks.
+    ///
+    bool EliminatePHINodes(MachineFunction &MF, MachineBasicBlock &MBB);
+    void LowerAtomicPHINode(MachineBasicBlock &MBB,
+                            MachineBasicBlock::iterator AfterPHIsIt);
+
+    /// analyzePHINodes - Gather information about the PHI nodes in
+    /// here. In particular, we want to map the number of uses of a virtual
+    /// register which is used in a PHI node. We map that to the BB the
+    /// vreg is coming from. This is used later to determine when the vreg
+    /// is killed in the BB.
+    ///
+    void analyzePHINodes(const MachineFunction& Fn);
+
+    /// Split critical edges where necessary for good coalescer performance.
+    bool SplitPHIEdges(MachineFunction &MF, MachineBasicBlock &MBB,
+                       LiveVariables &LV);
+
+    /// SplitCriticalEdge - Split a critical edge from A to B by
+    /// inserting a new MBB. Update branches in A and PHI instructions
+    /// in B. Return the new block.
+    MachineBasicBlock *SplitCriticalEdge(MachineBasicBlock *A,
+                                         MachineBasicBlock *B);
+
+    /// FindCopyInsertPoint - Find a safe place in MBB to insert a copy from
+    /// SrcReg when following the CFG edge to SuccMBB. This needs to be after
+    /// any def of SrcReg, but before any subsequent point where control flow
+    /// might jump out of the basic block.
+    MachineBasicBlock::iterator FindCopyInsertPoint(MachineBasicBlock &MBB,
+                                                    MachineBasicBlock &SuccMBB,
+                                                    unsigned SrcReg);
+
+    // SkipPHIsAndLabels - Copies need to be inserted after phi nodes and
+    // also after any exception handling labels: in landing pads execution
+    // starts at the label, so any copies placed before it won't be executed!
+    // We also deal with DBG_VALUEs, which are a bit tricky:
+    //  PHI
+    //  DBG_VALUE
+    //  LABEL
+    // Here the DBG_VALUE needs to be skipped, and if it refers to a PHI it
+    // needs to be annulled or, better, moved to follow the label, as well.
+    //  PHI
+    //  DBG_VALUE
+    //  no label
+    // Here it is not a good idea to skip the DBG_VALUE.
+    // FIXME: For now we skip and annul all DBG_VALUEs, maximally simple and
+    // maximally stupid.
+    MachineBasicBlock::iterator SkipPHIsAndLabels(MachineBasicBlock &MBB,
+                                                MachineBasicBlock::iterator I) {
+      // Rather than assuming that EH labels come before other kinds of labels,
+      // just skip all labels.
+      while (I != MBB.end() && 
+             (I->isPHI() || I->isLabel() || I->isDebugValue())) {
+        if (I->isDebugValue() && I->getNumOperands()==3 && 
+            I->getOperand(0).isReg())
+          I->getOperand(0).setReg(0U);
+        ++I;
+      }
+      return I;
+    }
+
+    typedef std::pair<unsigned, unsigned> BBVRegPair;
+    typedef DenseMap<BBVRegPair, unsigned> VRegPHIUse;
+
+    VRegPHIUse VRegPHIUseCount;
+
+    // Defs of PHI sources which are implicit_def.
+    SmallPtrSet<MachineInstr*, 4> ImpDefs;
+
+    // Map reusable lowered PHI node -> incoming join register.
+    typedef DenseMap<MachineInstr*, unsigned,
+                     MachineInstrExpressionTrait> LoweredPHIMap;
+    LoweredPHIMap LoweredPHIs;
+  };
+
+}
+
+#endif /* LLVM_CODEGEN_PHIELIMINATION_HPP */