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diff --git a/include/llvm/Analysis/PHITransAddr.h b/include/llvm/Analysis/PHITransAddr.h
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+++ b/include/llvm/Analysis/PHITransAddr.h
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+//===- PHITransAddr.h - PHI Translation for Addresses -----------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file declares the PHITransAddr class.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANALYSIS_PHITRANSADDR_H
+#define LLVM_ANALYSIS_PHITRANSADDR_H
+
+#include "llvm/Instruction.h"
+#include "llvm/ADT/SmallVector.h"
+
+namespace llvm {
+  class DominatorTree;
+  class TargetData;
+  
+/// PHITransAddr - An address value which tracks and handles phi translation.
+/// As we walk "up" the CFG through predecessors, we need to ensure that the
+/// address we're tracking is kept up to date.  For example, if we're analyzing
+/// an address of "&A[i]" and walk through the definition of 'i' which is a PHI
+/// node, we *must* phi translate i to get "&A[j]" or else we will analyze an
+/// incorrect pointer in the predecessor block.
+///
+/// This is designed to be a relatively small object that lives on the stack and
+/// is copyable.
+///
+class PHITransAddr {
+  /// Addr - The actual address we're analyzing.
+  Value *Addr;
+  
+  /// TD - The target data we are playing with if known, otherwise null.
+  const TargetData *TD;
+  
+  /// InstInputs - The inputs for our symbolic address.
+  SmallVector<Instruction*, 4> InstInputs;
+public:
+  PHITransAddr(Value *addr, const TargetData *td) : Addr(addr), TD(td) {
+    // If the address is an instruction, the whole thing is considered an input.
+    if (Instruction *I = dyn_cast<Instruction>(Addr))
+      InstInputs.push_back(I);
+  }
+  
+  Value *getAddr() const { return Addr; }
+  
+  /// NeedsPHITranslationFromBlock - Return true if moving from the specified
+  /// BasicBlock to its predecessors requires PHI translation.
+  bool NeedsPHITranslationFromBlock(BasicBlock *BB) const {
+    // We do need translation if one of our input instructions is defined in
+    // this block.
+    for (unsigned i = 0, e = InstInputs.size(); i != e; ++i)
+      if (InstInputs[i]->getParent() == BB)
+        return true;
+    return false;
+  }
+  
+  /// IsPotentiallyPHITranslatable - If this needs PHI translation, return true
+  /// if we have some hope of doing it.  This should be used as a filter to
+  /// avoid calling PHITranslateValue in hopeless situations.
+  bool IsPotentiallyPHITranslatable() const;
+  
+  /// PHITranslateValue - PHI translate the current address up the CFG from
+  /// CurBB to Pred, updating our state the reflect any needed changes.  This
+  /// returns true on failure and sets Addr to null.
+  bool PHITranslateValue(BasicBlock *CurBB, BasicBlock *PredBB);
+  
+  /// PHITranslateWithInsertion - PHI translate this value into the specified
+  /// predecessor block, inserting a computation of the value if it is
+  /// unavailable.
+  ///
+  /// All newly created instructions are added to the NewInsts list.  This
+  /// returns null on failure.
+  ///
+  Value *PHITranslateWithInsertion(BasicBlock *CurBB, BasicBlock *PredBB,
+                                   const DominatorTree &DT,
+                                   SmallVectorImpl<Instruction*> &NewInsts);
+  
+  void dump() const;
+  
+  /// Verify - Check internal consistency of this data structure.  If the
+  /// structure is valid, it returns true.  If invalid, it prints errors and
+  /// returns false.
+  bool Verify() const;
+private:
+  Value *PHITranslateSubExpr(Value *V, BasicBlock *CurBB, BasicBlock *PredBB);
+  
+  
+  /// GetAvailablePHITranslatedSubExpr - Return the value computed by
+  /// PHITranslateSubExpr if it dominates PredBB, otherwise return null.
+  Value *GetAvailablePHITranslatedSubExpr(Value *V,
+                                          BasicBlock *CurBB, BasicBlock *PredBB,
+                                          const DominatorTree &DT) const;
+  
+  /// InsertPHITranslatedSubExpr - Insert a computation of the PHI translated
+  /// version of 'V' for the edge PredBB->CurBB into the end of the PredBB
+  /// block.  All newly created instructions are added to the NewInsts list.
+  /// This returns null on failure.
+  ///
+  Value *InsertPHITranslatedSubExpr(Value *InVal, BasicBlock *CurBB,
+                                    BasicBlock *PredBB, const DominatorTree &DT,
+                                    SmallVectorImpl<Instruction*> &NewInsts);
+  
+  /// AddAsInput - If the specified value is an instruction, add it as an input.
+  Value *AddAsInput(Value *V) {
+    // If V is an instruction, it is now an input.
+    if (Instruction *VI = dyn_cast<Instruction>(V))
+      InstInputs.push_back(VI);
+    return V;
+  }
+  
+};
+
+} // end namespace llvm
+
+#endif