Publically export all of these classes from the ScalarEvolutions.cpp file

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12957 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Analysis/ScalarEvolutionExpressions.h

@@ -0,0 +1,461 @@
+//===- llvm/Analysis/ScalarEvolutionExpressions.h - SCEV Exprs --*- C++ -*-===//
+// 
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and 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;
+
+  enum SCEVTypes {
+    // These should be ordered in terms of increasing complexity to make the
+    // folders simpler.
+    scConstant, scTruncate, scZeroExtend, scAddExpr, scMulExpr, scUDivExpr,
+    scAddRecExpr, scUnknown, scCouldNotCompute
+  };
+
+  //===--------------------------------------------------------------------===//
+  /// SCEVConstant - This class represents a constant integer value.
+  ///
+  class SCEVConstant : public SCEV {
+    ConstantInt *V;
+    SCEVConstant(ConstantInt *v) : SCEV(scConstant), V(v) {}
+    
+    virtual ~SCEVConstant();
+  public:
+    /// get method - This just gets and returns a new SCEVConstant object.
+    ///
+    static SCEVHandle get(ConstantInt *V);
+
+    ConstantInt *getValue() const { return V; }
+
+    /// getValueRange - Return the tightest constant bounds that this value is
+    /// known to have.  This method is only valid on integer SCEV objects.
+    virtual ConstantRange getValueRange() const;
+
+    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;
+
+    Value *expandCodeFor(ScalarEvolutionRewriter &SER,
+                         Instruction *InsertPt) {
+      return (Value*)getValue();
+    }
+    
+    virtual void print(std::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;
+    }
+  };
+
+  //===--------------------------------------------------------------------===//
+  /// SCEVTruncateExpr - This class represents a truncation of an integer value
+  /// to a smaller integer value.
+  ///
+  class SCEVTruncateExpr : public SCEV {
+    SCEVHandle Op;
+    const Type *Ty;
+    SCEVTruncateExpr(const SCEVHandle &op, const Type *ty);
+    virtual ~SCEVTruncateExpr();
+  public:
+    /// get method - This just gets and returns a new SCEVTruncate object
+    ///
+    static SCEVHandle get(const SCEVHandle &Op, const Type *Ty);
+
+    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);
+    }
+
+    /// getValueRange - Return the tightest constant bounds that this value is
+    /// known to have.  This method is only valid on integer SCEV objects.
+    virtual ConstantRange getValueRange() const;
+
+    Value *expandCodeFor(ScalarEvolutionRewriter &SER,
+                         Instruction *InsertPt);
+    
+    virtual void print(std::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 SCEV {
+    SCEVHandle Op;
+    const Type *Ty;
+    SCEVZeroExtendExpr(const SCEVHandle &op, const Type *ty);
+    virtual ~SCEVZeroExtendExpr();
+  public:
+    /// get method - This just gets and returns a new SCEVZeroExtend object
+    ///
+    static SCEVHandle get(const SCEVHandle &Op, const Type *Ty);
+
+    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);
+    }
+
+    /// getValueRange - Return the tightest constant bounds that this value is
+    /// known to have.  This method is only valid on integer SCEV objects.
+    virtual ConstantRange getValueRange() const;
+
+    Value *expandCodeFor(ScalarEvolutionRewriter &SER,
+                         Instruction *InsertPt);
+    
+    virtual void print(std::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;
+    }
+  };
+
+
+  //===--------------------------------------------------------------------===//
+  /// SCEVCommutativeExpr - This node is the base class for n'ary commutative
+  /// operators.
+  ///
+  class SCEVCommutativeExpr : public SCEV {
+    std::vector<SCEVHandle> Operands;
+
+  protected:
+    SCEVCommutativeExpr(enum SCEVTypes T, const std::vector<SCEVHandle> &ops)
+      : SCEV(T) {
+      Operands.reserve(ops.size());
+      Operands.insert(Operands.end(), ops.begin(), ops.end());
+    }
+    ~SCEVCommutativeExpr();
+
+  public:
+    unsigned getNumOperands() const { return 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;
+    }
+
+    virtual bool hasComputableLoopEvolution(const Loop *L) const {
+      for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
+        if (getOperand(i)->hasComputableLoopEvolution(L)) return true;
+      return false;
+    }
+
+    virtual const char *getOperationStr() const = 0;
+
+    virtual const Type *getType() const { return getOperand(0)->getType(); }
+    virtual void print(std::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;
+    }
+  };
+
+
+  //===--------------------------------------------------------------------===//
+  /// SCEVAddExpr - This node represents an addition of some number of SCEVs.
+  ///
+  class SCEVAddExpr : public SCEVCommutativeExpr {
+    SCEVAddExpr(const std::vector<SCEVHandle> &ops)
+      : SCEVCommutativeExpr(scAddExpr, ops) {
+    }
+
+  public:
+    static SCEVHandle get(std::vector<SCEVHandle> &Ops);
+
+    static SCEVHandle get(const SCEVHandle &LHS, const SCEVHandle &RHS) {
+      std::vector<SCEVHandle> Ops;
+      Ops.push_back(LHS);
+      Ops.push_back(RHS);
+      return get(Ops);
+    }
+
+    static SCEVHandle get(const SCEVHandle &Op0, const SCEVHandle &Op1,
+                          const SCEVHandle &Op2) {
+      std::vector<SCEVHandle> Ops;
+      Ops.push_back(Op0);
+      Ops.push_back(Op1);
+      Ops.push_back(Op2);
+      return get(Ops);
+    }
+
+    virtual const char *getOperationStr() const { return " + "; }
+
+    Value *expandCodeFor(ScalarEvolutionRewriter &SER,
+                         Instruction *InsertPt);
+
+    /// 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 {
+    SCEVMulExpr(const std::vector<SCEVHandle> &ops)
+      : SCEVCommutativeExpr(scMulExpr, ops) {
+    }
+
+  public:
+    static SCEVHandle get(std::vector<SCEVHandle> &Ops);
+
+    static SCEVHandle get(const SCEVHandle &LHS, const SCEVHandle &RHS) {
+      std::vector<SCEVHandle> Ops;
+      Ops.push_back(LHS);
+      Ops.push_back(RHS);
+      return get(Ops);
+    }
+
+    virtual const char *getOperationStr() const { return " * "; }
+
+    Value *expandCodeFor(ScalarEvolutionRewriter &SER,
+                         Instruction *InsertPt);
+
+    /// 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 {
+    SCEVHandle LHS, RHS;
+    SCEVUDivExpr(const SCEVHandle &lhs, const SCEVHandle &rhs)
+      : SCEV(scUDivExpr), LHS(lhs), RHS(rhs) {}
+
+    virtual ~SCEVUDivExpr();
+  public:
+    /// get method - This just gets and returns a new SCEVUDiv object.
+    ///
+    static SCEVHandle get(const SCEVHandle &LHS, const SCEVHandle &RHS);
+
+    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);
+    }
+
+    virtual const Type *getType() const;
+
+    Value *expandCodeFor(ScalarEvolutionRewriter &SER,
+                         Instruction *InsertPt);
+    
+    void print(std::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.
+  ///
+  /// All operands of an AddRec are required to be loop invariant.
+  ///
+  class SCEVAddRecExpr : public SCEV {
+    std::vector<SCEVHandle> Operands;
+    const Loop *L;
+
+    SCEVAddRecExpr(const std::vector<SCEVHandle> &ops, const Loop *l)
+      : SCEV(scAddRecExpr), Operands(ops), L(l) {
+      for (unsigned i = 0, e = Operands.size(); i != e; ++i)
+        assert(Operands[i]->isLoopInvariant(l) &&
+               "Operands of AddRec must be loop-invariant!");
+    }
+    ~SCEVAddRecExpr();
+  public:
+    static SCEVHandle get(const SCEVHandle &Start, const SCEVHandle &Step,
+                          const Loop *);
+    static SCEVHandle get(std::vector<SCEVHandle> &Operands,
+                          const Loop *);
+    static SCEVHandle get(const std::vector<SCEVHandle> &Operands,
+                          const Loop *L) {
+      std::vector<SCEVHandle> NewOp(Operands);
+      return get(NewOp, L);
+    }
+
+    typedef std::vector<SCEVHandle>::const_iterator op_iterator;
+    op_iterator op_begin() const { return Operands.begin(); }
+    op_iterator op_end() const { return Operands.end(); }
+
+    unsigned getNumOperands() const { return Operands.size(); }
+    const SCEVHandle &getOperand(unsigned i) const { return Operands[i]; }
+    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() const {
+      if (getNumOperands() == 2) return getOperand(1);
+      return SCEVAddRecExpr::get(std::vector<SCEVHandle>(op_begin()+1,op_end()),
+                                 getLoop());
+    }
+
+    virtual bool hasComputableLoopEvolution(const Loop *QL) const {
+      if (L == QL) return true;
+      /// FIXME: What if the start or step value a recurrence for the specified
+      /// loop?
+      return false;
+    }
+
+    virtual bool isLoopInvariant(const Loop *QueryLoop) const;
+
+    virtual const Type *getType() const { return Operands[0]->getType(); }
+
+    Value *expandCodeFor(ScalarEvolutionRewriter &SER,
+                         Instruction *InsertPt);
+
+
+    /// 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) 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) const;
+
+
+    virtual void print(std::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;
+    }
+  };
+
+  //===--------------------------------------------------------------------===//
+  /// 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 {
+    Value *V;
+    SCEVUnknown(Value *v) : SCEV(scUnknown), V(v) {}
+
+  protected:
+    ~SCEVUnknown();
+  public:
+    /// get method - For SCEVUnknown, this just gets and returns a new
+    /// SCEVUnknown.
+    static SCEVHandle get(Value *V);
+
+    Value *getValue() const { return V; }
+
+    Value *expandCodeFor(ScalarEvolutionRewriter &SER,
+                         Instruction *InsertPt) {
+      return V;
+    }
+
+    virtual bool isLoopInvariant(const Loop *L) const;
+    virtual bool hasComputableLoopEvolution(const Loop *QL) const {
+      return false; // not computable
+    }
+
+    virtual const Type *getType() const;
+
+    virtual void print(std::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;
+    }
+  };
+}
+
+#endif
+