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diff --git a/include/llvm/Analysis/ScalarEvolutionExpander.h b/include/llvm/Analysis/ScalarEvolutionExpander.h
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+//===---- llvm/Analysis/ScalarEvolutionExpander.h - SCEV Exprs --*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines the classes used to generate code from scalar expressions.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANALYSIS_SCALAREVOLUTION_EXPANDER_H
+#define LLVM_ANALYSIS_SCALAREVOLUTION_EXPANDER_H
+
+#include "llvm/Instructions.h"
+#include "llvm/Type.h"
+#include "llvm/Analysis/ScalarEvolution.h"
+#include "llvm/Analysis/ScalarEvolutionExpressions.h"
+
+namespace llvm {
+  /// SCEVExpander - This class uses information about analyze scalars to
+  /// rewrite expressions in canonical form.
+  ///
+  /// Clients should create an instance of this class when rewriting is needed,
+  /// and destroy it when finished to allow the release of the associated 
+  /// memory.
+  struct SCEVExpander : public SCEVVisitor<SCEVExpander, Value*> {
+    ScalarEvolution &SE;
+    std::map<SCEVHandle, AssertingVH<Value> > InsertedExpressions;
+    std::set<Value*> InsertedValues;
+
+    BasicBlock::iterator InsertPt;
+
+    friend struct SCEVVisitor<SCEVExpander, Value*>;
+  public:
+    explicit SCEVExpander(ScalarEvolution &se)
+      : SE(se) {}
+
+    /// clear - Erase the contents of the InsertedExpressions map so that users
+    /// trying to expand the same expression into multiple BasicBlocks or
+    /// different places within the same BasicBlock can do so.
+    void clear() { InsertedExpressions.clear(); }
+
+    /// isInsertedInstruction - Return true if the specified instruction was
+    /// inserted by the code rewriter.  If so, the client should not modify the
+    /// instruction.
+    bool isInsertedInstruction(Instruction *I) const {
+      return InsertedValues.count(I);
+    }
+
+    /// isInsertedExpression - Return true if the the code rewriter has a
+    /// Value* recorded for the given expression.
+    bool isInsertedExpression(const SCEV *S) const {
+      return InsertedExpressions.count(S);
+    }
+
+    /// getOrInsertCanonicalInductionVariable - This method returns the
+    /// canonical induction variable of the specified type for the specified
+    /// loop (inserting one if there is none).  A canonical induction variable
+    /// starts at zero and steps by one on each iteration.
+    Value *getOrInsertCanonicalInductionVariable(const Loop *L, const Type *Ty){
+      assert(Ty->isInteger() && "Can only insert integer induction variables!");
+      SCEVHandle H = SE.getAddRecExpr(SE.getIntegerSCEV(0, Ty),
+                                      SE.getIntegerSCEV(1, Ty), L);
+      return expand(H);
+    }
+
+    /// addInsertedValue - Remember the specified instruction as being the
+    /// canonical form for the specified SCEV.
+    void addInsertedValue(Value *V, const SCEV *S) {
+      InsertedExpressions[S] = V;
+      InsertedValues.insert(V);
+    }
+
+    void setInsertionPoint(BasicBlock::iterator NewIP) { InsertPt = NewIP; }
+
+    BasicBlock::iterator getInsertionPoint() const { return InsertPt; }
+
+    /// expandCodeFor - Insert code to directly compute the specified SCEV
+    /// expression into the program.  The inserted code is inserted into the
+    /// SCEVExpander's current insertion point. If a type is specified, the
+    /// result will be expanded to have that type, with a cast if necessary.
+    Value *expandCodeFor(SCEVHandle SH, const Type *Ty = 0);
+
+    /// expandCodeFor - Insert code to directly compute the specified SCEV
+    /// expression into the program.  The inserted code is inserted into the
+    /// specified block.
+    Value *expandCodeFor(SCEVHandle SH, const Type *Ty,
+                         BasicBlock::iterator IP) {
+      setInsertionPoint(IP);
+      return expandCodeFor(SH, Ty);
+    }
+
+    /// InsertCastOfTo - Insert a cast of V to the specified type, doing what
+    /// we can to share the casts.
+    Value *InsertCastOfTo(Instruction::CastOps opcode, Value *V,
+                          const Type *Ty);
+
+    /// InsertNoopCastOfTo - Insert a cast of V to the specified type,
+    /// which must be possible with a noop cast.
+    Value *InsertNoopCastOfTo(Value *V, const Type *Ty);
+
+    /// InsertBinop - Insert the specified binary operator, doing a small amount
+    /// of work to avoid inserting an obviously redundant operation.
+    Value *InsertBinop(Instruction::BinaryOps Opcode, Value *LHS,
+                       Value *RHS, BasicBlock::iterator InsertPt);
+
+  private:
+    /// expandAddToGEP - Expand a SCEVAddExpr with a pointer type into a GEP
+    /// instead of using ptrtoint+arithmetic+inttoptr.
+    Value *expandAddToGEP(const SCEVHandle *op_begin, const SCEVHandle *op_end,
+                          const PointerType *PTy, const Type *Ty, Value *V);
+
+    Value *expand(const SCEV *S);
+
+    Value *visitConstant(const SCEVConstant *S) {
+      return S->getValue();
+    }
+
+    Value *visitTruncateExpr(const SCEVTruncateExpr *S);
+
+    Value *visitZeroExtendExpr(const SCEVZeroExtendExpr *S);
+
+    Value *visitSignExtendExpr(const SCEVSignExtendExpr *S);
+
+    Value *visitAddExpr(const SCEVAddExpr *S);
+
+    Value *visitMulExpr(const SCEVMulExpr *S);
+
+    Value *visitUDivExpr(const SCEVUDivExpr *S);
+
+    Value *visitAddRecExpr(const SCEVAddRecExpr *S);
+
+    Value *visitSMaxExpr(const SCEVSMaxExpr *S);
+
+    Value *visitUMaxExpr(const SCEVUMaxExpr *S);
+
+    Value *visitUnknown(const SCEVUnknown *S) {
+      return S->getValue();
+    }
+  };
+}
+
+#endif
+