X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FAnalysis%2FScalarEvolutionExpressions.h;h=b6f0ae54cfa0d087e2b8d24057184db561a0bdc2;hb=f46c674a16669518dbb24d4cdd4bfc904dd3b505;hp=8be1a934bc1388d326b1d594dd53c4cfa982b1d3;hpb=753ad615f96c3d56d6f17983bdba88012e88677c;p=oota-llvm.git diff --git a/include/llvm/Analysis/ScalarEvolutionExpressions.h b/include/llvm/Analysis/ScalarEvolutionExpressions.h index 8be1a934bc1..b6f0ae54cfa 100644 --- a/include/llvm/Analysis/ScalarEvolutionExpressions.h +++ b/include/llvm/Analysis/ScalarEvolutionExpressions.h @@ -15,6 +15,7 @@ #define LLVM_ANALYSIS_SCALAREVOLUTION_EXPRESSIONS_H #include "llvm/Analysis/ScalarEvolution.h" +#include "llvm/Support/ErrorHandling.h" namespace llvm { class ConstantInt; @@ -25,8 +26,8 @@ namespace llvm { // 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 + scUDivExpr, scAddRecExpr, scUMaxExpr, scSMaxExpr, + scUnknown, scCouldNotCompute }; //===--------------------------------------------------------------------===// @@ -36,32 +37,12 @@ namespace llvm { friend class ScalarEvolution; ConstantInt *V; - explicit SCEVConstant(ConstantInt *v) : - SCEV(scConstant), V(v) {} + SCEVConstant(const FoldingSetNodeIDRef ID, ConstantInt *v) : + SCEV(ID, scConstant), V(v) {} 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; - - const SCEV* replaceSymbolicValuesWithConcrete(const SCEV* Sym, - const SCEV* Conc, - ScalarEvolution &SE) const { - return this; - } - - bool dominates(BasicBlock *BB, DominatorTree *DT) const { - return true; - } - - virtual void print(raw_ostream &OS) const; + Type *getType() const { return V->getType(); } /// Methods for support type inquiry through isa, cast, and dyn_cast: static inline bool classof(const SCEVConstant *S) { return true; } @@ -75,24 +56,15 @@ namespace llvm { /// class SCEVCastExpr : public SCEV { protected: - const SCEV* Op; - const Type *Ty; + const SCEV *Op; + Type *Ty; - SCEVCastExpr(unsigned SCEVTy, const SCEV* op, const Type *ty); + SCEVCastExpr(const FoldingSetNodeIDRef ID, + unsigned SCEVTy, const SCEV *op, Type *ty); public: - const SCEV* 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; + const SCEV *getOperand() const { return Op; } + Type *getType() const { return Ty; } /// Methods for support type inquiry through isa, cast, and dyn_cast: static inline bool classof(const SCEVCastExpr *S) { return true; } @@ -110,20 +82,10 @@ namespace llvm { class SCEVTruncateExpr : public SCEVCastExpr { friend class ScalarEvolution; - SCEVTruncateExpr(const SCEV* op, const Type *ty); + SCEVTruncateExpr(const FoldingSetNodeIDRef ID, + const SCEV *op, Type *ty); public: - const SCEV* replaceSymbolicValuesWithConcrete(const SCEV* Sym, - const SCEV* Conc, - ScalarEvolution &SE) const { - const SCEV* 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) { @@ -138,20 +100,10 @@ namespace llvm { class SCEVZeroExtendExpr : public SCEVCastExpr { friend class ScalarEvolution; - SCEVZeroExtendExpr(const SCEV* op, const Type *ty); + SCEVZeroExtendExpr(const FoldingSetNodeIDRef ID, + const SCEV *op, Type *ty); public: - const SCEV* replaceSymbolicValuesWithConcrete(const SCEV* Sym, - const SCEV* Conc, - ScalarEvolution &SE) const { - const SCEV* 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) { @@ -166,20 +118,10 @@ namespace llvm { class SCEVSignExtendExpr : public SCEVCastExpr { friend class ScalarEvolution; - SCEVSignExtendExpr(const SCEV* op, const Type *ty); + SCEVSignExtendExpr(const FoldingSetNodeIDRef ID, + const SCEV *op, Type *ty); public: - const SCEV* replaceSymbolicValuesWithConcrete(const SCEV* Sym, - const SCEV* Conc, - ScalarEvolution &SE) const { - const SCEV* 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) { @@ -194,48 +136,34 @@ namespace llvm { /// class SCEVNAryExpr : public SCEV { protected: - SmallVector Operands; + // Since SCEVs are immutable, ScalarEvolution allocates operand + // arrays with its SCEVAllocator, so this class just needs a simple + // pointer rather than a more elaborate vector-like data structure. + // This also avoids the need for a non-trivial destructor. + const SCEV *const *Operands; + size_t NumOperands; - SCEVNAryExpr(enum SCEVTypes T, const SmallVectorImpl &ops) - : SCEV(T), Operands(ops.begin(), ops.end()) {} + SCEVNAryExpr(const FoldingSetNodeIDRef ID, + enum SCEVTypes T, const SCEV *const *O, size_t N) + : SCEV(ID, T), Operands(O), NumOperands(N) {} public: - unsigned getNumOperands() const { return (unsigned)Operands.size(); } - const SCEV* getOperand(unsigned i) const { - assert(i < Operands.size() && "Operand index out of range!"); + size_t getNumOperands() const { return NumOperands; } + const SCEV *getOperand(unsigned i) const { + assert(i < NumOperands && "Operand index out of range!"); return Operands[i]; } - const SmallVectorImpl &getOperands() const { return Operands; } - typedef SmallVectorImpl::const_iterator op_iterator; - op_iterator op_begin() const { return Operands.begin(); } - op_iterator op_end() const { return Operands.end(); } + typedef const SCEV *const *op_iterator; + op_iterator op_begin() const { return Operands; } + op_iterator op_end() const { return Operands + NumOperands; } - 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; - } + Type *getType() const { return getOperand(0)->getType(); } - // 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; + NoWrapFlags getNoWrapFlags(NoWrapFlags Mask = NoWrapMask) const { + return (NoWrapFlags)(SubclassData & Mask); } - 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) { @@ -253,19 +181,11 @@ namespace llvm { /// class SCEVCommutativeExpr : public SCEVNAryExpr { protected: - SCEVCommutativeExpr(enum SCEVTypes T, - const SmallVectorImpl &ops) - : SCEVNAryExpr(T, ops) {} + SCEVCommutativeExpr(const FoldingSetNodeIDRef ID, + enum SCEVTypes T, const SCEV *const *O, size_t N) + : SCEVNAryExpr(ID, T, O, N) {} public: - const SCEV* replaceSymbolicValuesWithConcrete(const SCEV* Sym, - const SCEV* 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) { @@ -274,6 +194,11 @@ namespace llvm { S->getSCEVType() == scSMaxExpr || S->getSCEVType() == scUMaxExpr; } + + /// Set flags for a non-recurrence without clearing previously set flags. + void setNoWrapFlags(NoWrapFlags Flags) { + SubclassData |= Flags; + } }; @@ -283,12 +208,18 @@ namespace llvm { class SCEVAddExpr : public SCEVCommutativeExpr { friend class ScalarEvolution; - explicit SCEVAddExpr(const SmallVectorImpl &ops) - : SCEVCommutativeExpr(scAddExpr, ops) { + SCEVAddExpr(const FoldingSetNodeIDRef ID, + const SCEV *const *O, size_t N) + : SCEVCommutativeExpr(ID, scAddExpr, O, N) { } public: - virtual const char *getOperationStr() const { return " + "; } + Type *getType() const { + // Use the type of the last operand, which is likely to be a pointer + // type, if there is one. This doesn't usually matter, but it can help + // reduce casts when the expressions are expanded. + return getOperand(getNumOperands() - 1)->getType(); + } /// Methods for support type inquiry through isa, cast, and dyn_cast: static inline bool classof(const SCEVAddExpr *S) { return true; } @@ -303,13 +234,12 @@ namespace llvm { class SCEVMulExpr : public SCEVCommutativeExpr { friend class ScalarEvolution; - explicit SCEVMulExpr(const SmallVectorImpl &ops) - : SCEVCommutativeExpr(scMulExpr, ops) { + SCEVMulExpr(const FoldingSetNodeIDRef ID, + const SCEV *const *O, size_t N) + : SCEVCommutativeExpr(ID, scMulExpr, O, N) { } 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) { @@ -324,41 +254,24 @@ namespace llvm { class SCEVUDivExpr : public SCEV { friend class ScalarEvolution; - const SCEV* LHS; - const SCEV* RHS; - SCEVUDivExpr(const SCEV* lhs, const SCEV* rhs) - : SCEV(scUDivExpr), LHS(lhs), RHS(rhs) {} + const SCEV *LHS; + const SCEV *RHS; + SCEVUDivExpr(const FoldingSetNodeIDRef ID, const SCEV *lhs, const SCEV *rhs) + : SCEV(ID, scUDivExpr), LHS(lhs), RHS(rhs) {} public: - const SCEV* getLHS() const { return LHS; } - const SCEV* getRHS() const { return RHS; } - - virtual bool isLoopInvariant(const Loop *L) const { - return LHS->isLoopInvariant(L) && RHS->isLoopInvariant(L); - } + const SCEV *getLHS() const { return LHS; } + const SCEV *getRHS() const { return RHS; } - virtual bool hasComputableLoopEvolution(const Loop *L) const { - return LHS->hasComputableLoopEvolution(L) && - RHS->hasComputableLoopEvolution(L); + Type *getType() const { + // In most cases the types of LHS and RHS will be the same, but in some + // crazy cases one or the other may be a pointer. ScalarEvolution doesn't + // depend on the type for correctness, but handling types carefully can + // avoid extra casts in the SCEVExpander. The LHS is more likely to be + // a pointer type than the RHS, so use the RHS' type here. + return getRHS()->getType(); } - const SCEV* replaceSymbolicValuesWithConcrete(const SCEV* Sym, - const SCEV* Conc, - ScalarEvolution &SE) const { - const SCEV* L = LHS->replaceSymbolicValuesWithConcrete(Sym, Conc, SE); - const SCEV* 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) { @@ -381,33 +294,25 @@ namespace llvm { const Loop *L; - SCEVAddRecExpr(const SmallVectorImpl &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(const FoldingSetNodeIDRef ID, + const SCEV *const *O, size_t N, const Loop *l) + : SCEVNAryExpr(ID, scAddRecExpr, O, N), L(l) {} public: - const SCEV* getStart() const { return Operands[0]; } + const SCEV *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. - const SCEV* getStepRecurrence(ScalarEvolution &SE) const { + /// We cannot determine whether the step recurrence has self-wraparound. + const SCEV *getStepRecurrence(ScalarEvolution &SE) const { if (isAffine()) return getOperand(1); - return SE.getAddRecExpr(SmallVector(op_begin()+1,op_end()), - getLoop()); - } - - virtual bool hasComputableLoopEvolution(const Loop *QL) const { - if (L == QL) return true; - return false; + return SE.getAddRecExpr(SmallVector(op_begin()+1, + op_end()), + getLoop(), FlagAnyWrap); } - 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 { @@ -423,9 +328,18 @@ namespace llvm { return getNumOperands() == 3; } + /// Set flags for a recurrence without clearing any previously set flags. + /// For AddRec, either NUW or NSW implies NW. Keep track of this fact here + /// to make it easier to propagate flags. + void setNoWrapFlags(NoWrapFlags Flags) { + if (Flags & (FlagNUW | FlagNSW)) + Flags = ScalarEvolution::setFlags(Flags, FlagNW); + SubclassData |= Flags; + } + /// evaluateAtIteration - Return the value of this chain of recurrences at /// the specified iteration number. - const SCEV* evaluateAtIteration(const SCEV* It, ScalarEvolution &SE) const; + const SCEV *evaluateAtIteration(const SCEV *It, ScalarEvolution &SE) const; /// getNumIterationsInRange - Return the number of iterations of this loop /// that produce values in the specified constant range. Another way of @@ -433,14 +347,14 @@ namespace llvm { /// 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. - const SCEV* getNumIterationsInRange(ConstantRange Range, + const SCEV *getNumIterationsInRange(ConstantRange Range, ScalarEvolution &SE) const; - const SCEV* replaceSymbolicValuesWithConcrete(const SCEV* Sym, - const SCEV* Conc, - ScalarEvolution &SE) const; - - virtual void print(raw_ostream &OS) const; + /// getPostIncExpr - Return an expression representing the value of + /// this expression one iteration of the loop ahead. + const SCEVAddRecExpr *getPostIncExpr(ScalarEvolution &SE) const { + return cast(SE.getAddExpr(this, getStepRecurrence(SE))); + } /// Methods for support type inquiry through isa, cast, and dyn_cast: static inline bool classof(const SCEVAddRecExpr *S) { return true; } @@ -456,13 +370,14 @@ namespace llvm { class SCEVSMaxExpr : public SCEVCommutativeExpr { friend class ScalarEvolution; - explicit SCEVSMaxExpr(const SmallVectorImpl &ops) - : SCEVCommutativeExpr(scSMaxExpr, ops) { + SCEVSMaxExpr(const FoldingSetNodeIDRef ID, + const SCEV *const *O, size_t N) + : SCEVCommutativeExpr(ID, scSMaxExpr, O, N) { + // Max never overflows. + setNoWrapFlags((NoWrapFlags)(FlagNUW | FlagNSW)); } 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) { @@ -477,13 +392,14 @@ namespace llvm { class SCEVUMaxExpr : public SCEVCommutativeExpr { friend class ScalarEvolution; - explicit SCEVUMaxExpr(const SmallVectorImpl &ops) - : SCEVCommutativeExpr(scUMaxExpr, ops) { + SCEVUMaxExpr(const FoldingSetNodeIDRef ID, + const SCEV *const *O, size_t N) + : SCEVCommutativeExpr(ID, scUMaxExpr, O, N) { + // Max never overflows. + setNoWrapFlags((NoWrapFlags)(FlagNUW | FlagNSW)); } 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) { @@ -491,39 +407,45 @@ namespace llvm { } }; - //===--------------------------------------------------------------------===// /// 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, and only represent it as its LLVM Value. This is the "bottom" /// value for the analysis. /// - class SCEVUnknown : public SCEV { + class SCEVUnknown : public SCEV, private CallbackVH { friend class ScalarEvolution; - Value *V; - explicit SCEVUnknown(Value *v) : - SCEV(scUnknown), V(v) {} - - public: - Value *getValue() const { return V; } + // Implement CallbackVH. + virtual void deleted(); + virtual void allUsesReplacedWith(Value *New); - virtual bool isLoopInvariant(const Loop *L) const; - virtual bool hasComputableLoopEvolution(const Loop *QL) const { - return false; // not computable - } + /// SE - The parent ScalarEvolution value. This is used to update + /// the parent's maps when the value associated with a SCEVUnknown + /// is deleted or RAUW'd. + ScalarEvolution *SE; - const SCEV* replaceSymbolicValuesWithConcrete(const SCEV* Sym, - const SCEV* Conc, - ScalarEvolution &SE) const { - if (&*Sym == this) return Conc; - return this; - } + /// Next - The next pointer in the linked list of all + /// SCEVUnknown instances owned by a ScalarEvolution. + SCEVUnknown *Next; + + SCEVUnknown(const FoldingSetNodeIDRef ID, Value *V, + ScalarEvolution *se, SCEVUnknown *next) : + SCEV(ID, scUnknown), CallbackVH(V), SE(se), Next(next) {} - bool dominates(BasicBlock *BB, DominatorTree *DT) const; + public: + Value *getValue() const { return getValPtr(); } - virtual const Type *getType() const; + /// isSizeOf, isAlignOf, isOffsetOf - Test whether this is a special + /// constant representing a type size, alignment, or field offset in + /// a target-independent manner, and hasn't happened to have been + /// folded with other operations into something unrecognizable. This + /// is mainly only useful for pretty-printing and other situations + /// where it isn't absolutely required for these to succeed. + bool isSizeOf(Type *&AllocTy) const; + bool isAlignOf(Type *&AllocTy) const; + bool isOffsetOf(Type *&STy, Constant *&FieldNo) const; - virtual void print(raw_ostream &OS) const; + Type *getType() const { return getValPtr()->getType(); } /// Methods for support type inquiry through isa, cast, and dyn_cast: static inline bool classof(const SCEVUnknown *S) { return true; } @@ -563,14 +485,12 @@ namespace llvm { case scCouldNotCompute: return ((SC*)this)->visitCouldNotCompute((const SCEVCouldNotCompute*)S); default: - assert(0 && "Unknown SCEV type!"); - abort(); + llvm_unreachable("Unknown SCEV type!"); } } RetVal visitCouldNotCompute(const SCEVCouldNotCompute *S) { - assert(0 && "Invalid use of SCEVCouldNotCompute!"); - abort(); + llvm_unreachable("Invalid use of SCEVCouldNotCompute!"); return RetVal(); } };