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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_SCALAREVOLUTIONEXPANDER_H
+#define LLVM_ANALYSIS_SCALAREVOLUTIONEXPANDER_H
+
+#include "llvm/Analysis/ScalarEvolutionExpressions.h"
+#include "llvm/Analysis/ScalarEvolutionNormalization.h"
+#include "llvm/Analysis/TargetFolder.h"
+#include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/ValueHandle.h"
+#include <set>
+
+namespace llvm {
+  class TargetTransformInfo;
+
+  /// Return true if the given expression is safe to expand in the sense that
+  /// all materialized values are safe to speculate.
+  bool isSafeToExpand(const SCEV *S, ScalarEvolution &SE);
+
+  /// 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.
+  class SCEVExpander : public SCEVVisitor<SCEVExpander, Value*> {
+    ScalarEvolution &SE;
+
+    // New instructions receive a name to identifies them with the current pass.
+    const char* IVName;
+
+    // InsertedExpressions caches Values for reuse, so must track RAUW.
+    std::map<std::pair<const SCEV *, Instruction *>, TrackingVH<Value> >
+      InsertedExpressions;
+    // InsertedValues only flags inserted instructions so needs no RAUW.
+    std::set<AssertingVH<Value> > InsertedValues;
+    std::set<AssertingVH<Value> > InsertedPostIncValues;
+
+    /// RelevantLoops - A memoization of the "relevant" loop for a given SCEV.
+    DenseMap<const SCEV *, const Loop *> RelevantLoops;
+
+    /// PostIncLoops - Addrecs referring to any of the given loops are expanded
+    /// in post-inc mode. For example, expanding {1,+,1}<L> in post-inc mode
+    /// returns the add instruction that adds one to the phi for {0,+,1}<L>,
+    /// as opposed to a new phi starting at 1. This is only supported in
+    /// non-canonical mode.
+    PostIncLoopSet PostIncLoops;
+
+    /// IVIncInsertPos - When this is non-null, addrecs expanded in the
+    /// loop it indicates should be inserted with increments at
+    /// IVIncInsertPos.
+    const Loop *IVIncInsertLoop;
+
+    /// IVIncInsertPos - When expanding addrecs in the IVIncInsertLoop loop,
+    /// insert the IV increment at this position.
+    Instruction *IVIncInsertPos;
+
+    /// Phis that complete an IV chain. Reuse
+    std::set<AssertingVH<PHINode> > ChainedPhis;
+
+    /// CanonicalMode - When true, expressions are expanded in "canonical"
+    /// form. In particular, addrecs are expanded as arithmetic based on
+    /// a canonical induction variable. When false, expression are expanded
+    /// in a more literal form.
+    bool CanonicalMode;
+
+    /// When invoked from LSR, the expander is in "strength reduction" mode. The
+    /// only difference is that phi's are only reused if they are already in
+    /// "expanded" form.
+    bool LSRMode;
+
+    typedef IRBuilder<true, TargetFolder> BuilderType;
+    BuilderType Builder;
+
+#ifndef NDEBUG
+    const char *DebugType;
+#endif
+
+    friend struct SCEVVisitor<SCEVExpander, Value*>;
+
+  public:
+    /// SCEVExpander - Construct a SCEVExpander in "canonical" mode.
+    explicit SCEVExpander(ScalarEvolution &se, const char *name)
+      : SE(se), IVName(name), IVIncInsertLoop(nullptr), IVIncInsertPos(nullptr),
+        CanonicalMode(true), LSRMode(false),
+        Builder(se.getContext(), TargetFolder(se.DL)) {
+#ifndef NDEBUG
+      DebugType = "";
+#endif
+    }
+
+#ifndef NDEBUG
+    void setDebugType(const char* s) { DebugType = s; }
+#endif
+
+    /// 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();
+      InsertedValues.clear();
+      InsertedPostIncValues.clear();
+      ChainedPhis.clear();
+    }
+
+    /// 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.
+    PHINode *getOrInsertCanonicalInductionVariable(const Loop *L, Type *Ty);
+
+    /// getIVIncOperand - Return the induction variable increment's IV operand.
+    Instruction *getIVIncOperand(Instruction *IncV, Instruction *InsertPos,
+                                 bool allowScale);
+
+    /// hoistIVInc - Utility for hoisting an IV increment.
+    bool hoistIVInc(Instruction *IncV, Instruction *InsertPos);
+
+    /// replaceCongruentIVs - replace congruent phis with their most canonical
+    /// representative. Return the number of phis eliminated.
+    unsigned replaceCongruentIVs(Loop *L, const DominatorTree *DT,
+                                 SmallVectorImpl<WeakVH> &DeadInsts,
+                                 const TargetTransformInfo *TTI = nullptr);
+
+    /// expandCodeFor - Insert code to directly compute the specified SCEV
+    /// expression into the program.  The inserted code is inserted into the
+    /// specified block.
+    Value *expandCodeFor(const SCEV *SH, Type *Ty, Instruction *I);
+
+    /// setIVIncInsertPos - Set the current IV increment loop and position.
+    void setIVIncInsertPos(const Loop *L, Instruction *Pos) {
+      assert(!CanonicalMode &&
+             "IV increment positions are not supported in CanonicalMode");
+      IVIncInsertLoop = L;
+      IVIncInsertPos = Pos;
+    }
+
+    /// setPostInc - Enable post-inc expansion for addrecs referring to the
+    /// given loops. Post-inc expansion is only supported in non-canonical
+    /// mode.
+    void setPostInc(const PostIncLoopSet &L) {
+      assert(!CanonicalMode &&
+             "Post-inc expansion is not supported in CanonicalMode");
+      PostIncLoops = L;
+    }
+
+    /// clearPostInc - Disable all post-inc expansion.
+    void clearPostInc() {
+      PostIncLoops.clear();
+
+      // When we change the post-inc loop set, cached expansions may no
+      // longer be valid.
+      InsertedPostIncValues.clear();
+    }
+
+    /// disableCanonicalMode - Disable the behavior of expanding expressions in
+    /// canonical form rather than in a more literal form. Non-canonical mode
+    /// is useful for late optimization passes.
+    void disableCanonicalMode() { CanonicalMode = false; }
+
+    void enableLSRMode() { LSRMode = true; }
+
+    /// clearInsertPoint - Clear the current insertion point. This is useful
+    /// if the instruction that had been serving as the insertion point may
+    /// have been deleted.
+    void clearInsertPoint() {
+      Builder.ClearInsertionPoint();
+    }
+
+    /// 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) || InsertedPostIncValues.count(I);
+    }
+
+    void setChainedPhi(PHINode *PN) { ChainedPhis.insert(PN); }
+
+  private:
+    LLVMContext &getContext() const { return SE.getContext(); }
+
+    /// 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);
+
+    /// ReuseOrCreateCast - Arange for there to be a cast of V to Ty at IP,
+    /// reusing an existing cast if a suitable one exists, moving an existing
+    /// cast if a suitable one exists but isn't in the right place, or
+    /// or creating a new one.
+    Value *ReuseOrCreateCast(Value *V, Type *Ty,
+                             Instruction::CastOps Op,
+                             BasicBlock::iterator IP);
+
+    /// InsertNoopCastOfTo - Insert a cast of V to the specified type,
+    /// which must be possible with a noop cast, doing what we can to
+    /// share the casts.
+    Value *InsertNoopCastOfTo(Value *V, Type *Ty);
+
+    /// expandAddToGEP - Expand a SCEVAddExpr with a pointer type into a GEP
+    /// instead of using ptrtoint+arithmetic+inttoptr.
+    Value *expandAddToGEP(const SCEV *const *op_begin,
+                          const SCEV *const *op_end,
+                          PointerType *PTy, Type *Ty, Value *V);
+
+    Value *expand(const SCEV *S);
+
+    /// 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(const SCEV *SH, Type *Ty = nullptr);
+
+    /// getRelevantLoop - Determine the most "relevant" loop for the given SCEV.
+    const Loop *getRelevantLoop(const SCEV *);
+
+    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();
+    }
+
+    void rememberInstruction(Value *I);
+
+    bool isNormalAddRecExprPHI(PHINode *PN, Instruction *IncV, const Loop *L);
+
+    bool isExpandedAddRecExprPHI(PHINode *PN, Instruction *IncV, const Loop *L);
+
+    Value *expandAddRecExprLiterally(const SCEVAddRecExpr *);
+    PHINode *getAddRecExprPHILiterally(const SCEVAddRecExpr *Normalized,
+                                       const Loop *L,
+                                       Type *ExpandTy,
+                                       Type *IntTy,
+                                       Type *&TruncTy,
+                                       bool &InvertStep);
+    Value *expandIVInc(PHINode *PN, Value *StepV, const Loop *L,
+                       Type *ExpandTy, Type *IntTy, bool useSubtract);
+  };
+}
+
+#endif