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diff --git a/include/llvm/CodeGen/LiveStackAnalysis.h b/include/llvm/CodeGen/LiveStackAnalysis.h
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+++ b/include/llvm/CodeGen/LiveStackAnalysis.h
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+//===-- LiveStackAnalysis.h - Live Stack Slot Analysis ----------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the live stack slot analysis pass. It is analogous to
+// live interval analysis except it's analyzing liveness of stack slots rather
+// than registers.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_LIVESTACK_ANALYSIS_H
+#define LLVM_CODEGEN_LIVESTACK_ANALYSIS_H
+
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/LiveInterval.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Support/Allocator.h"
+#include <map>
+
+namespace llvm {
+
+  class LiveStacks : public MachineFunctionPass {
+    /// Special pool allocator for VNInfo's (LiveInterval val#).
+    ///
+    BumpPtrAllocator VNInfoAllocator;
+
+    /// S2IMap - Stack slot indices to live interval mapping.
+    ///
+    typedef std::map<int, LiveInterval> SS2IntervalMap;
+    SS2IntervalMap S2IMap;
+
+    /// S2RCMap - Stack slot indices to register class mapping.
+    std::map<int, const TargetRegisterClass*> S2RCMap;
+    
+  public:
+    static char ID; // Pass identification, replacement for typeid
+    LiveStacks() : MachineFunctionPass(&ID) {}
+
+    typedef SS2IntervalMap::iterator iterator;
+    typedef SS2IntervalMap::const_iterator const_iterator;
+    const_iterator begin() const { return S2IMap.begin(); }
+    const_iterator end() const { return S2IMap.end(); }
+    iterator begin() { return S2IMap.begin(); }
+    iterator end() { return S2IMap.end(); }
+
+    void scaleNumbering(int factor);
+
+    unsigned getNumIntervals() const { return (unsigned)S2IMap.size(); }
+
+    LiveInterval &getOrCreateInterval(int Slot, const TargetRegisterClass *RC) {
+      assert(Slot >= 0 && "Spill slot indice must be >= 0");
+      SS2IntervalMap::iterator I = S2IMap.find(Slot);
+      if (I == S2IMap.end()) {
+        I = S2IMap.insert(I,std::make_pair(Slot, LiveInterval(Slot,0.0F,true)));
+        S2RCMap.insert(std::make_pair(Slot, RC));
+      } else {
+        // Use the largest common subclass register class.
+        const TargetRegisterClass *OldRC = S2RCMap[Slot];
+        S2RCMap[Slot] = getCommonSubClass(OldRC, RC);
+      }
+      return I->second;
+    }
+
+    LiveInterval &getInterval(int Slot) {
+      assert(Slot >= 0 && "Spill slot indice must be >= 0");
+      SS2IntervalMap::iterator I = S2IMap.find(Slot);
+      assert(I != S2IMap.end() && "Interval does not exist for stack slot");
+      return I->second;
+    }
+
+    const LiveInterval &getInterval(int Slot) const {
+      assert(Slot >= 0 && "Spill slot indice must be >= 0");
+      SS2IntervalMap::const_iterator I = S2IMap.find(Slot);
+      assert(I != S2IMap.end() && "Interval does not exist for stack slot");
+      return I->second;
+    }
+
+    bool hasInterval(int Slot) const {
+      return S2IMap.count(Slot);
+    }
+
+    const TargetRegisterClass *getIntervalRegClass(int Slot) const {
+      assert(Slot >= 0 && "Spill slot indice must be >= 0");
+      std::map<int, const TargetRegisterClass*>::const_iterator
+        I = S2RCMap.find(Slot);
+      assert(I != S2RCMap.end() &&
+             "Register class info does not exist for stack slot");
+      return I->second;
+    }
+
+    BumpPtrAllocator& getVNInfoAllocator() { return VNInfoAllocator; }
+
+    virtual void getAnalysisUsage(AnalysisUsage &AU) const;
+    virtual void releaseMemory();
+
+    /// runOnMachineFunction - pass entry point
+    virtual bool runOnMachineFunction(MachineFunction&);
+
+    /// print - Implement the dump method.
+    virtual void print(std::ostream &O, const Module* = 0) const;
+    void print(std::ostream *O, const Module* M = 0) const {
+      if (O) print(*O, M);
+    }
+  };
+}
+
+#endif /* LLVM_CODEGEN_LIVESTACK_ANALYSIS_H */