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diff --git a/include/llvm/Analysis/ScalarEvolutionExpressions.h b/include/llvm/Analysis/ScalarEvolutionExpressions.h
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+//===- llvm/Analysis/ScalarEvolutionExpressions.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 represent and build scalar expressions.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANALYSIS_SCALAREVOLUTION_EXPRESSIONS_H
+#define LLVM_ANALYSIS_SCALAREVOLUTION_EXPRESSIONS_H
+
+#include "llvm/Analysis/ScalarEvolution.h"
+
+namespace llvm {
+ class ConstantInt;
+ class ConstantRange;
+ class APInt;
+ class DominatorTree;
+
+ enum SCEVTypes {
+ // These should be ordered in terms of increasing complexity to make the
+ // folders simpler.
+ scConstant, scTruncate, scZeroExtend, scSignExtend, scAddExpr, scMulExpr,
+ scUDivExpr, scAddRecExpr, scUMaxExpr, scSMaxExpr, scUnknown,
+ scCouldNotCompute
+ };
+
+ //===--------------------------------------------------------------------===//
+ /// SCEVConstant - This class represents a constant integer value.
+ ///
+ class SCEVConstant : public SCEV {
+ friend class ScalarEvolution;
+
+ ConstantInt *V;
+ explicit SCEVConstant(ConstantInt *v) : SCEV(scConstant), V(v) {}
+
+ virtual ~SCEVConstant();
+ public:
+ ConstantInt *getValue() const { return V; }
+
+ virtual bool isLoopInvariant(const Loop *L) const {
+ return true;
+ }
+
+ virtual bool hasComputableLoopEvolution(const Loop *L) const {
+ return false; // Not loop variant
+ }
+
+ virtual const Type *getType() const;
+
+ SCEVHandle replaceSymbolicValuesWithConcrete(const SCEVHandle &Sym,
+ const SCEVHandle &Conc,
+ ScalarEvolution &SE) const {
+ return this;
+ }
+
+ bool dominates(BasicBlock *BB, DominatorTree *DT) const {
+ return true;
+ }
+
+ virtual void print(raw_ostream &OS) const;
+
+ /// Methods for support type inquiry through isa, cast, and dyn_cast:
+ static inline bool classof(const SCEVConstant *S) { return true; }
+ static inline bool classof(const SCEV *S) {
+ return S->getSCEVType() == scConstant;
+ }
+ };
+
+ //===--------------------------------------------------------------------===//
+ /// SCEVCastExpr - This is the base class for unary cast operator classes.
+ ///
+ class SCEVCastExpr : public SCEV {
+ protected:
+ SCEVHandle Op;
+ const Type *Ty;
+
+ SCEVCastExpr(unsigned SCEVTy, const SCEVHandle &op, const Type *ty);
+ virtual ~SCEVCastExpr();
+
+ public:
+ const SCEVHandle &getOperand() const { return Op; }
+ virtual const Type *getType() const { return Ty; }
+
+ virtual bool isLoopInvariant(const Loop *L) const {
+ return Op->isLoopInvariant(L);
+ }
+
+ virtual bool hasComputableLoopEvolution(const Loop *L) const {
+ return Op->hasComputableLoopEvolution(L);
+ }
+
+ virtual bool dominates(BasicBlock *BB, DominatorTree *DT) const;
+
+ /// Methods for support type inquiry through isa, cast, and dyn_cast:
+ static inline bool classof(const SCEVCastExpr *S) { return true; }
+ static inline bool classof(const SCEV *S) {
+ return S->getSCEVType() == scTruncate ||
+ S->getSCEVType() == scZeroExtend ||
+ S->getSCEVType() == scSignExtend;
+ }
+ };
+
+ //===--------------------------------------------------------------------===//
+ /// SCEVTruncateExpr - This class represents a truncation of an integer value
+ /// to a smaller integer value.
+ ///
+ class SCEVTruncateExpr : public SCEVCastExpr {
+ friend class ScalarEvolution;
+
+ SCEVTruncateExpr(const SCEVHandle &op, const Type *ty);
+ virtual ~SCEVTruncateExpr();
+
+ public:
+ SCEVHandle replaceSymbolicValuesWithConcrete(const SCEVHandle &Sym,
+ const SCEVHandle &Conc,
+ ScalarEvolution &SE) const {
+ SCEVHandle H = Op->replaceSymbolicValuesWithConcrete(Sym, Conc, SE);
+ if (H == Op)
+ return this;
+ return SE.getTruncateExpr(H, Ty);
+ }
+
+ virtual void print(raw_ostream &OS) const;
+
+ /// Methods for support type inquiry through isa, cast, and dyn_cast:
+ static inline bool classof(const SCEVTruncateExpr *S) { return true; }
+ static inline bool classof(const SCEV *S) {
+ return S->getSCEVType() == scTruncate;
+ }
+ };
+
+ //===--------------------------------------------------------------------===//
+ /// SCEVZeroExtendExpr - This class represents a zero extension of a small
+ /// integer value to a larger integer value.
+ ///
+ class SCEVZeroExtendExpr : public SCEVCastExpr {
+ friend class ScalarEvolution;
+
+ SCEVZeroExtendExpr(const SCEVHandle &op, const Type *ty);
+ virtual ~SCEVZeroExtendExpr();
+
+ public:
+ SCEVHandle replaceSymbolicValuesWithConcrete(const SCEVHandle &Sym,
+ const SCEVHandle &Conc,
+ ScalarEvolution &SE) const {
+ SCEVHandle H = Op->replaceSymbolicValuesWithConcrete(Sym, Conc, SE);
+ if (H == Op)
+ return this;
+ return SE.getZeroExtendExpr(H, Ty);
+ }
+
+ virtual void print(raw_ostream &OS) const;
+
+ /// Methods for support type inquiry through isa, cast, and dyn_cast:
+ static inline bool classof(const SCEVZeroExtendExpr *S) { return true; }
+ static inline bool classof(const SCEV *S) {
+ return S->getSCEVType() == scZeroExtend;
+ }
+ };
+
+ //===--------------------------------------------------------------------===//
+ /// SCEVSignExtendExpr - This class represents a sign extension of a small
+ /// integer value to a larger integer value.
+ ///
+ class SCEVSignExtendExpr : public SCEVCastExpr {
+ friend class ScalarEvolution;
+
+ SCEVSignExtendExpr(const SCEVHandle &op, const Type *ty);
+ virtual ~SCEVSignExtendExpr();
+
+ public:
+ SCEVHandle replaceSymbolicValuesWithConcrete(const SCEVHandle &Sym,
+ const SCEVHandle &Conc,
+ ScalarEvolution &SE) const {
+ SCEVHandle H = Op->replaceSymbolicValuesWithConcrete(Sym, Conc, SE);
+ if (H == Op)
+ return this;
+ return SE.getSignExtendExpr(H, Ty);
+ }
+
+ virtual void print(raw_ostream &OS) const;
+
+ /// Methods for support type inquiry through isa, cast, and dyn_cast:
+ static inline bool classof(const SCEVSignExtendExpr *S) { return true; }
+ static inline bool classof(const SCEV *S) {
+ return S->getSCEVType() == scSignExtend;
+ }
+ };
+
+
+ //===--------------------------------------------------------------------===//
+ /// SCEVNAryExpr - This node is a base class providing common
+ /// functionality for n'ary operators.
+ ///
+ class SCEVNAryExpr : public SCEV {
+ protected:
+ std::vector<SCEVHandle> Operands;
+
+ SCEVNAryExpr(enum SCEVTypes T, const std::vector<SCEVHandle> &ops)
+ : SCEV(T), Operands(ops) {}
+ virtual ~SCEVNAryExpr() {}
+
+ public:
+ unsigned getNumOperands() const { return (unsigned)Operands.size(); }
+ const SCEVHandle &getOperand(unsigned i) const {
+ assert(i < Operands.size() && "Operand index out of range!");
+ return Operands[i];
+ }
+
+ const std::vector<SCEVHandle> &getOperands() const { return Operands; }
+ typedef std::vector<SCEVHandle>::const_iterator op_iterator;
+ op_iterator op_begin() const { return Operands.begin(); }
+ op_iterator op_end() const { return Operands.end(); }
+
+ virtual bool isLoopInvariant(const Loop *L) const {
+ for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
+ if (!getOperand(i)->isLoopInvariant(L)) return false;
+ return true;
+ }
+
+ // hasComputableLoopEvolution - N-ary expressions have computable loop
+ // evolutions iff they have at least one operand that varies with the loop,
+ // but that all varying operands are computable.
+ virtual bool hasComputableLoopEvolution(const Loop *L) const {
+ bool HasVarying = false;
+ for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
+ if (!getOperand(i)->isLoopInvariant(L)) {
+ if (getOperand(i)->hasComputableLoopEvolution(L))
+ HasVarying = true;
+ else
+ return false;
+ }
+ return HasVarying;
+ }
+
+ bool dominates(BasicBlock *BB, DominatorTree *DT) const;
+
+ virtual const Type *getType() const { return getOperand(0)->getType(); }
+
+ /// Methods for support type inquiry through isa, cast, and dyn_cast:
+ static inline bool classof(const SCEVNAryExpr *S) { return true; }
+ static inline bool classof(const SCEV *S) {
+ return S->getSCEVType() == scAddExpr ||
+ S->getSCEVType() == scMulExpr ||
+ S->getSCEVType() == scSMaxExpr ||
+ S->getSCEVType() == scUMaxExpr ||
+ S->getSCEVType() == scAddRecExpr;
+ }
+ };
+
+ //===--------------------------------------------------------------------===//
+ /// SCEVCommutativeExpr - This node is the base class for n'ary commutative
+ /// operators.
+ ///
+ class SCEVCommutativeExpr : public SCEVNAryExpr {
+ protected:
+ SCEVCommutativeExpr(enum SCEVTypes T, const std::vector<SCEVHandle> &ops)
+ : SCEVNAryExpr(T, ops) {}
+ ~SCEVCommutativeExpr();
+
+ public:
+ SCEVHandle replaceSymbolicValuesWithConcrete(const SCEVHandle &Sym,
+ const SCEVHandle &Conc,
+ ScalarEvolution &SE) const;
+
+ virtual const char *getOperationStr() const = 0;
+
+ virtual void print(raw_ostream &OS) const;
+
+ /// Methods for support type inquiry through isa, cast, and dyn_cast:
+ static inline bool classof(const SCEVCommutativeExpr *S) { return true; }
+ static inline bool classof(const SCEV *S) {
+ return S->getSCEVType() == scAddExpr ||
+ S->getSCEVType() == scMulExpr ||
+ S->getSCEVType() == scSMaxExpr ||
+ S->getSCEVType() == scUMaxExpr;
+ }
+ };
+
+
+ //===--------------------------------------------------------------------===//
+ /// SCEVAddExpr - This node represents an addition of some number of SCEVs.
+ ///
+ class SCEVAddExpr : public SCEVCommutativeExpr {
+ friend class ScalarEvolution;
+
+ explicit SCEVAddExpr(const std::vector<SCEVHandle> &ops)
+ : SCEVCommutativeExpr(scAddExpr, ops) {
+ }
+
+ public:
+ virtual const char *getOperationStr() const { return " + "; }
+
+ /// Methods for support type inquiry through isa, cast, and dyn_cast:
+ static inline bool classof(const SCEVAddExpr *S) { return true; }
+ static inline bool classof(const SCEV *S) {
+ return S->getSCEVType() == scAddExpr;
+ }
+ };
+
+ //===--------------------------------------------------------------------===//
+ /// SCEVMulExpr - This node represents multiplication of some number of SCEVs.
+ ///
+ class SCEVMulExpr : public SCEVCommutativeExpr {
+ friend class ScalarEvolution;
+
+ explicit SCEVMulExpr(const std::vector<SCEVHandle> &ops)
+ : SCEVCommutativeExpr(scMulExpr, ops) {
+ }
+
+ public:
+ virtual const char *getOperationStr() const { return " * "; }
+
+ /// Methods for support type inquiry through isa, cast, and dyn_cast:
+ static inline bool classof(const SCEVMulExpr *S) { return true; }
+ static inline bool classof(const SCEV *S) {
+ return S->getSCEVType() == scMulExpr;
+ }
+ };
+
+
+ //===--------------------------------------------------------------------===//
+ /// SCEVUDivExpr - This class represents a binary unsigned division operation.
+ ///
+ class SCEVUDivExpr : public SCEV {
+ friend class ScalarEvolution;
+
+ SCEVHandle LHS, RHS;
+ SCEVUDivExpr(const SCEVHandle &lhs, const SCEVHandle &rhs)
+ : SCEV(scUDivExpr), LHS(lhs), RHS(rhs) {}
+
+ virtual ~SCEVUDivExpr();
+ public:
+ const SCEVHandle &getLHS() const { return LHS; }
+ const SCEVHandle &getRHS() const { return RHS; }
+
+ virtual bool isLoopInvariant(const Loop *L) const {
+ return LHS->isLoopInvariant(L) && RHS->isLoopInvariant(L);
+ }
+
+ virtual bool hasComputableLoopEvolution(const Loop *L) const {
+ return LHS->hasComputableLoopEvolution(L) &&
+ RHS->hasComputableLoopEvolution(L);
+ }
+
+ SCEVHandle replaceSymbolicValuesWithConcrete(const SCEVHandle &Sym,
+ const SCEVHandle &Conc,
+ ScalarEvolution &SE) const {
+ SCEVHandle L = LHS->replaceSymbolicValuesWithConcrete(Sym, Conc, SE);
+ SCEVHandle R = RHS->replaceSymbolicValuesWithConcrete(Sym, Conc, SE);
+ if (L == LHS && R == RHS)
+ return this;
+ else
+ return SE.getUDivExpr(L, R);
+ }
+
+ bool dominates(BasicBlock *BB, DominatorTree *DT) const;
+
+ virtual const Type *getType() const;
+
+ void print(raw_ostream &OS) const;
+
+ /// Methods for support type inquiry through isa, cast, and dyn_cast:
+ static inline bool classof(const SCEVUDivExpr *S) { return true; }
+ static inline bool classof(const SCEV *S) {
+ return S->getSCEVType() == scUDivExpr;
+ }
+ };
+
+
+ //===--------------------------------------------------------------------===//
+ /// SCEVAddRecExpr - This node represents a polynomial recurrence on the trip
+ /// count of the specified loop. This is the primary focus of the
+ /// ScalarEvolution framework; all the other SCEV subclasses are mostly just
+ /// supporting infrastructure to allow SCEVAddRecExpr expressions to be
+ /// created and analyzed.
+ ///
+ /// All operands of an AddRec are required to be loop invariant.
+ ///
+ class SCEVAddRecExpr : public SCEVNAryExpr {
+ friend class ScalarEvolution;
+
+ const Loop *L;
+
+ SCEVAddRecExpr(const std::vector<SCEVHandle> &ops, const Loop *l)
+ : SCEVNAryExpr(scAddRecExpr, ops), L(l) {
+ for (size_t i = 0, e = Operands.size(); i != e; ++i)
+ assert(Operands[i]->isLoopInvariant(l) &&
+ "Operands of AddRec must be loop-invariant!");
+ }
+ ~SCEVAddRecExpr();
+
+ public:
+ const SCEVHandle &getStart() const { return Operands[0]; }
+ const Loop *getLoop() const { return L; }
+
+ /// getStepRecurrence - This method constructs and returns the recurrence
+ /// indicating how much this expression steps by. If this is a polynomial
+ /// of degree N, it returns a chrec of degree N-1.
+ SCEVHandle getStepRecurrence(ScalarEvolution &SE) const {
+ if (isAffine()) return getOperand(1);
+ return SE.getAddRecExpr(std::vector<SCEVHandle>(op_begin()+1,op_end()),
+ getLoop());
+ }
+
+ virtual bool hasComputableLoopEvolution(const Loop *QL) const {
+ if (L == QL) return true;
+ return false;
+ }
+
+ virtual bool isLoopInvariant(const Loop *QueryLoop) const;
+
+ /// isAffine - Return true if this is an affine AddRec (i.e., it represents
+ /// an expressions A+B*x where A and B are loop invariant values.
+ bool isAffine() const {
+ // We know that the start value is invariant. This expression is thus
+ // affine iff the step is also invariant.
+ return getNumOperands() == 2;
+ }
+
+ /// isQuadratic - Return true if this is an quadratic AddRec (i.e., it
+ /// represents an expressions A+B*x+C*x^2 where A, B and C are loop
+ /// invariant values. This corresponds to an addrec of the form {L,+,M,+,N}
+ bool isQuadratic() const {
+ return getNumOperands() == 3;
+ }
+
+ /// evaluateAtIteration - Return the value of this chain of recurrences at
+ /// the specified iteration number.
+ SCEVHandle evaluateAtIteration(SCEVHandle It, ScalarEvolution &SE) const;
+
+ /// getNumIterationsInRange - Return the number of iterations of this loop
+ /// that produce values in the specified constant range. Another way of
+ /// looking at this is that it returns the first iteration number where the
+ /// value is not in the condition, thus computing the exit count. If the
+ /// iteration count can't be computed, an instance of SCEVCouldNotCompute is
+ /// returned.
+ SCEVHandle getNumIterationsInRange(ConstantRange Range,
+ ScalarEvolution &SE) const;
+
+ SCEVHandle replaceSymbolicValuesWithConcrete(const SCEVHandle &Sym,
+ const SCEVHandle &Conc,
+ ScalarEvolution &SE) const;
+
+ virtual void print(raw_ostream &OS) const;
+
+ /// Methods for support type inquiry through isa, cast, and dyn_cast:
+ static inline bool classof(const SCEVAddRecExpr *S) { return true; }
+ static inline bool classof(const SCEV *S) {
+ return S->getSCEVType() == scAddRecExpr;
+ }
+ };
+
+
+ //===--------------------------------------------------------------------===//
+ /// SCEVSMaxExpr - This class represents a signed maximum selection.
+ ///
+ class SCEVSMaxExpr : public SCEVCommutativeExpr {
+ friend class ScalarEvolution;
+
+ explicit SCEVSMaxExpr(const std::vector<SCEVHandle> &ops)
+ : SCEVCommutativeExpr(scSMaxExpr, ops) {
+ }
+
+ public:
+ virtual const char *getOperationStr() const { return " smax "; }
+
+ /// Methods for support type inquiry through isa, cast, and dyn_cast:
+ static inline bool classof(const SCEVSMaxExpr *S) { return true; }
+ static inline bool classof(const SCEV *S) {
+ return S->getSCEVType() == scSMaxExpr;
+ }
+ };
+
+
+ //===--------------------------------------------------------------------===//
+ /// SCEVUMaxExpr - This class represents an unsigned maximum selection.
+ ///
+ class SCEVUMaxExpr : public SCEVCommutativeExpr {
+ friend class ScalarEvolution;
+
+ explicit SCEVUMaxExpr(const std::vector<SCEVHandle> &ops)
+ : SCEVCommutativeExpr(scUMaxExpr, ops) {
+ }
+
+ public:
+ virtual const char *getOperationStr() const { return " umax "; }
+
+ /// Methods for support type inquiry through isa, cast, and dyn_cast:
+ static inline bool classof(const SCEVUMaxExpr *S) { return true; }
+ static inline bool classof(const SCEV *S) {
+ return S->getSCEVType() == scUMaxExpr;
+ }
+ };
+
+
+ //===--------------------------------------------------------------------===//
+ /// SCEVUnknown - This means that we are dealing with an entirely unknown SCEV
+ /// value, and only represent it as it's LLVM Value. This is the "bottom"
+ /// value for the analysis.
+ ///
+ class SCEVUnknown : public SCEV {
+ friend class ScalarEvolution;
+
+ Value *V;
+ explicit SCEVUnknown(Value *v) : SCEV(scUnknown), V(v) {}
+
+ protected:
+ ~SCEVUnknown();
+ public:
+ Value *getValue() const { return V; }
+
+ virtual bool isLoopInvariant(const Loop *L) const;
+ virtual bool hasComputableLoopEvolution(const Loop *QL) const {
+ return false; // not computable
+ }
+
+ SCEVHandle replaceSymbolicValuesWithConcrete(const SCEVHandle &Sym,
+ const SCEVHandle &Conc,
+ ScalarEvolution &SE) const {
+ if (&*Sym == this) return Conc;
+ return this;
+ }
+
+ bool dominates(BasicBlock *BB, DominatorTree *DT) const;
+
+ virtual const Type *getType() const;
+
+ virtual void print(raw_ostream &OS) const;
+
+ /// Methods for support type inquiry through isa, cast, and dyn_cast:
+ static inline bool classof(const SCEVUnknown *S) { return true; }
+ static inline bool classof(const SCEV *S) {
+ return S->getSCEVType() == scUnknown;
+ }
+ };
+
+ /// SCEVVisitor - This class defines a simple visitor class that may be used
+ /// for various SCEV analysis purposes.
+ template<typename SC, typename RetVal=void>
+ struct SCEVVisitor {
+ RetVal visit(const SCEV *S) {
+ switch (S->getSCEVType()) {
+ case scConstant:
+ return ((SC*)this)->visitConstant((const SCEVConstant*)S);
+ case scTruncate:
+ return ((SC*)this)->visitTruncateExpr((const SCEVTruncateExpr*)S);
+ case scZeroExtend:
+ return ((SC*)this)->visitZeroExtendExpr((const SCEVZeroExtendExpr*)S);
+ case scSignExtend:
+ return ((SC*)this)->visitSignExtendExpr((const SCEVSignExtendExpr*)S);
+ case scAddExpr:
+ return ((SC*)this)->visitAddExpr((const SCEVAddExpr*)S);
+ case scMulExpr:
+ return ((SC*)this)->visitMulExpr((const SCEVMulExpr*)S);
+ case scUDivExpr:
+ return ((SC*)this)->visitUDivExpr((const SCEVUDivExpr*)S);
+ case scAddRecExpr:
+ return ((SC*)this)->visitAddRecExpr((const SCEVAddRecExpr*)S);
+ case scSMaxExpr:
+ return ((SC*)this)->visitSMaxExpr((const SCEVSMaxExpr*)S);
+ case scUMaxExpr:
+ return ((SC*)this)->visitUMaxExpr((const SCEVUMaxExpr*)S);
+ case scUnknown:
+ return ((SC*)this)->visitUnknown((const SCEVUnknown*)S);
+ case scCouldNotCompute:
+ return ((SC*)this)->visitCouldNotCompute((const SCEVCouldNotCompute*)S);
+ default:
+ assert(0 && "Unknown SCEV type!");
+ abort();
+ }
+ }
+
+ RetVal visitCouldNotCompute(const SCEVCouldNotCompute *S) {
+ assert(0 && "Invalid use of SCEVCouldNotCompute!");
+ abort();
+ return RetVal();
+ }
+ };
+}
+
+#endif
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