X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FValue.h;h=7e7b415ffdeed671b1ba2ec26cf13a283633a236;hb=4b938958bcc59586508bc9681e75c2e3f5164672;hp=99bc8affa4bed1174aa14dc916c325528f6f4cf1;hpb=48486893f46d2e12e926682a3ecb908716bc66c4;p=oota-llvm.git diff --git a/include/llvm/Value.h b/include/llvm/Value.h index 99bc8affa4b..7e7b415ffde 100644 --- a/include/llvm/Value.h +++ b/include/llvm/Value.h @@ -1,9 +1,13 @@ //===-- llvm/Value.h - Definition of the Value class ------------*- C++ -*-===// // -// This file defines the very important Value class. This is subclassed by a -// bunch of other important classes, like Instruction, Function, Type, etc... +// The LLVM Compiler Infrastructure // -// This file also defines the Use<> template for users of value. +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file declares the Value class. // //===----------------------------------------------------------------------===// @@ -11,13 +15,13 @@ #define LLVM_VALUE_H #include "llvm/AbstractTypeUser.h" -#include "Support/Annotation.h" -#include "Support/Casting.h" -#include -#include +#include "llvm/Use.h" +#include "llvm/Support/Casting.h" +#include +#include + +namespace llvm { -class User; -class Type; class Constant; class Argument; class Instruction; @@ -25,66 +29,115 @@ class BasicBlock; class GlobalValue; class Function; class GlobalVariable; -class SymbolTable; +class GlobalAlias; +class InlineAsm; +class ValueSymbolTable; +class TypeSymbolTable; +template class StringMapEntry; +template +class AssertingVH; +typedef StringMapEntry ValueName; +class raw_ostream; +class AssemblyAnnotationWriter; +class ValueHandleBase; //===----------------------------------------------------------------------===// // Value Class //===----------------------------------------------------------------------===// -/// Value - The base class of all values computed by a program that may be used -/// as operands to other values. +/// This is a very important LLVM class. It is the base class of all values +/// computed by a program that may be used as operands to other values. Value is +/// the super class of other important classes such as Instruction and Function. +/// All Values have a Type. Type is not a subclass of Value. All types can have +/// a name and they should belong to some Module. Setting the name on the Value +/// automatically updates the module's symbol table. /// -class Value : public Annotable, // Values are annotable - public AbstractTypeUser { // Values use potentially abstract types -public: - enum ValueTy { - TypeVal, // This is an instance of Type - ConstantVal, // This is an instance of Constant - ArgumentVal, // This is an instance of Argument - InstructionVal, // This is an instance of Instruction - BasicBlockVal, // This is an instance of BasicBlock - FunctionVal, // This is an instance of Function - GlobalVariableVal, // This is an instance of GlobalVariable - }; +/// Every value has a "use list" that keeps track of which other Values are +/// using this Value. A Value can also have an arbitrary number of ValueHandle +/// objects that watch it and listen to RAUW and Destroy events see +/// llvm/Support/ValueHandle.h for details. +/// +/// @brief LLVM Value Representation +class Value { + const unsigned char SubclassID; // Subclass identifier (for isa/dyn_cast) + unsigned char HasValueHandle : 1; // Has a ValueHandle pointing to this? +protected: + /// SubclassOptionalData - This member is similar to SubclassData, however it + /// is for holding information which may be used to aid optimization, but + /// which may be cleared to zero without affecting conservative + /// interpretation. + unsigned char SubclassOptionalData : 7; + /// SubclassData - This member is defined by this class, but is not used for + /// anything. Subclasses can use it to hold whatever state they find useful. + /// This field is initialized to zero by the ctor. + unsigned short SubclassData; private: - std::vector Uses; - std::string Name; - PATypeHandle Ty; - ValueTy VTy; + PATypeHolder VTy; + Use *UseList; + + friend class ValueSymbolTable; // Allow ValueSymbolTable to directly mod Name. + friend class SymbolTable; // Allow SymbolTable to directly poke Name. + friend class ValueHandleBase; + ValueName *Name; void operator=(const Value &); // Do not implement Value(const Value &); // Do not implement + public: - Value(const Type *Ty, ValueTy vty, const std::string &name = ""); + Value(const Type *Ty, unsigned scid); virtual ~Value(); - + /// dump - Support for debugging, callable in GDB: V->dump() // - void dump() const; + virtual void dump() const; - /// print - Implement operator<< on Value... + /// print - Implement operator<< on Value. /// - virtual void print(std::ostream &O) const = 0; - + void print(std::ostream &O, AssemblyAnnotationWriter *AAW = 0) const; + void print(raw_ostream &O, AssemblyAnnotationWriter *AAW = 0) const; + /// All values are typed, get the type of this value. /// - inline const Type *getType() const { return Ty; } - + inline const Type *getType() const { return VTy; } + // All values can potentially be named... - inline bool hasName() const { return Name != ""; } - inline const std::string &getName() const { return Name; } + inline bool hasName() const { return Name != 0; } + ValueName *getValueName() const { return Name; } - virtual void setName(const std::string &name, SymbolTable * = 0) { - Name = name; - } + /// getNameStart - Return a pointer to a null terminated string for this name. + /// Note that names can have null characters within the string as well as at + /// their end. This always returns a non-null pointer. + const char *getNameStart() const; + /// getNameEnd - Return a pointer to the end of the name. + const char *getNameEnd() const { return getNameStart() + getNameLen(); } - /// getValueType - Return the immediate subclass of this Value. - /// - inline ValueTy getValueType() const { return VTy; } + /// isName - Return true if this value has the name specified by the provided + /// nul terminated string. + bool isName(const char *N) const; + /// getNameLen - Return the length of the string, correctly handling nul + /// characters embedded into them. + unsigned getNameLen() const; + + /// getName()/getNameStr() - Return the name of the specified value, + /// *constructing a string* to hold it. Because these are guaranteed to + /// construct a string, they are very expensive and should be avoided. + std::string getName() const { return getNameStr(); } + std::string getNameStr() const; + + + void setName(const std::string &name); + void setName(const char *Name, unsigned NameLen); + void setName(const char *Name); // Takes a null-terminated string. + + + /// takeName - transfer the name from V to this value, setting V's name to + /// empty. It is an error to call V->takeName(V). + void takeName(Value *V); + /// replaceAllUsesWith - Go through the uses list for this definition and make - /// each use point to "V" instead of "this". After this completes, 'this's + /// each use point to "V" instead of "this". After this completes, 'this's /// use list is guaranteed to be empty. /// void replaceAllUsesWith(Value *V); @@ -93,132 +146,199 @@ public: // Only use when in type resolution situations! void uncheckedReplaceAllUsesWith(Value *V); - /// refineAbstractType - This function is implemented because we use - /// potentially abstract types, and these types may be resolved to more - /// concrete types after we are constructed. - /// - virtual void refineAbstractType(const DerivedType *OldTy, const Type *NewTy); - + /// clearOptionalData - Clear any optional optimization data from this Value. + /// Transformation passes must call this method whenever changing the IR + /// in a way that would affect the values produced by this Value, unless + /// it takes special care to ensure correctness in some other way. + void clearOptionalData() { SubclassOptionalData = 0; } + //---------------------------------------------------------------------- - // Methods for handling the vector of uses of this Value. + // Methods for handling the chain of uses of this Value. // - typedef std::vector::iterator use_iterator; - typedef std::vector::const_iterator use_const_iterator; - - inline unsigned use_size() const { return Uses.size(); } - inline bool use_empty() const { return Uses.empty(); } - inline use_iterator use_begin() { return Uses.begin(); } - inline use_const_iterator use_begin() const { return Uses.begin(); } - inline use_iterator use_end() { return Uses.end(); } - inline use_const_iterator use_end() const { return Uses.end(); } - inline User *use_back() { return Uses.back(); } - inline const User *use_back() const { return Uses.back(); } - - /// addUse/killUse - These two methods should only be used by the Use class - /// below. - inline void addUse(User *I) { Uses.push_back(I); } - void killUse(User *I); -}; + typedef value_use_iterator use_iterator; + typedef value_use_iterator use_const_iterator; -inline std::ostream &operator<<(std::ostream &OS, const Value *V) { - if (V == 0) - OS << " value!\n"; - else - V->print(OS); - return OS; -} + bool use_empty() const { return UseList == 0; } + use_iterator use_begin() { return use_iterator(UseList); } + use_const_iterator use_begin() const { return use_const_iterator(UseList); } + use_iterator use_end() { return use_iterator(0); } + use_const_iterator use_end() const { return use_const_iterator(0); } + User *use_back() { return *use_begin(); } + const User *use_back() const { return *use_begin(); } -inline std::ostream &operator<<(std::ostream &OS, const Value &V) { - V.print(OS); - return OS; -} + /// hasOneUse - Return true if there is exactly one user of this value. This + /// is specialized because it is a common request and does not require + /// traversing the whole use list. + /// + bool hasOneUse() const { + use_const_iterator I = use_begin(), E = use_end(); + if (I == E) return false; + return ++I == E; + } + + /// hasNUses - Return true if this Value has exactly N users. + /// + bool hasNUses(unsigned N) const; + /// hasNUsesOrMore - Return true if this value has N users or more. This is + /// logically equivalent to getNumUses() >= N. + /// + bool hasNUsesOrMore(unsigned N) const; -//===----------------------------------------------------------------------===// -// Use Class -//===----------------------------------------------------------------------===// + bool isUsedInBasicBlock(const BasicBlock *BB) const; -// Use is here to make keeping the "use" list of a Value up-to-date really easy. -// -class Use { - Value *Val; - User *U; -public: - inline Use(Value *v, User *user) { - Val = v; U = user; - if (Val) Val->addUse(U); - } + /// getNumUses - This method computes the number of uses of this Value. This + /// is a linear time operation. Use hasOneUse, hasNUses, or hasMoreThanNUses + /// to check for specific values. + unsigned getNumUses() const; - inline Use(const Use &user) { - Val = 0; - U = user.U; - operator=(user.Val); - } - inline ~Use() { if (Val) Val->killUse(U); } - inline operator Value*() const { return Val; } - - inline Value *operator=(Value *V) { - if (Val) Val->killUse(U); - Val = V; - if (V) V->addUse(U); - return V; + /// addUse - This method should only be used by the Use class. + /// + void addUse(Use &U) { U.addToList(&UseList); } + + /// An enumeration for keeping track of the concrete subclass of Value that + /// is actually instantiated. Values of this enumeration are kept in the + /// Value classes SubclassID field. They are used for concrete type + /// identification. + enum ValueTy { + ArgumentVal, // This is an instance of Argument + BasicBlockVal, // This is an instance of BasicBlock + FunctionVal, // This is an instance of Function + GlobalAliasVal, // This is an instance of GlobalAlias + GlobalVariableVal, // This is an instance of GlobalVariable + UndefValueVal, // This is an instance of UndefValue + ConstantExprVal, // This is an instance of ConstantExpr + ConstantAggregateZeroVal, // This is an instance of ConstantAggregateNull + ConstantIntVal, // This is an instance of ConstantInt + ConstantFPVal, // This is an instance of ConstantFP + ConstantArrayVal, // This is an instance of ConstantArray + ConstantStructVal, // This is an instance of ConstantStruct + ConstantVectorVal, // This is an instance of ConstantVector + ConstantPointerNullVal, // This is an instance of ConstantPointerNull + MDStringVal, // This is an instance of MDString + MDNodeVal, // This is an instance of MDNode + InlineAsmVal, // This is an instance of InlineAsm + PseudoSourceValueVal, // This is an instance of PseudoSourceValue + InstructionVal, // This is an instance of Instruction + + // Markers: + ConstantFirstVal = FunctionVal, + ConstantLastVal = MDNodeVal + }; + + /// getValueID - Return an ID for the concrete type of this object. This is + /// used to implement the classof checks. This should not be used for any + /// other purpose, as the values may change as LLVM evolves. Also, note that + /// for instructions, the Instruction's opcode is added to InstructionVal. So + /// this means three things: + /// # there is no value with code InstructionVal (no opcode==0). + /// # there are more possible values for the value type than in ValueTy enum. + /// # the InstructionVal enumerator must be the highest valued enumerator in + /// the ValueTy enum. + unsigned getValueID() const { + return SubclassID; } - inline Value *operator->() { return Val; } - inline const Value *operator->() const { return Val; } + // Methods for support type inquiry through isa, cast, and dyn_cast: + static inline bool classof(const Value *) { + return true; // Values are always values. + } - inline Value *get() { return Val; } - inline const Value *get() const { return Val; } + /// getRawType - This should only be used to implement the vmcore library. + /// + const Type *getRawType() const { return VTy.getRawType(); } - inline const Use &operator=(const Use &user) { - if (Val) Val->killUse(U); - Val = user.Val; - Val->addUse(U); - return *this; + /// stripPointerCasts - This method strips off any unneeded pointer + /// casts from the specified value, returning the original uncasted value. + /// Note that the returned value has pointer type if the specified value does. + Value *stripPointerCasts(); + const Value *stripPointerCasts() const { + return const_cast(this)->stripPointerCasts(); } -}; -template<> struct simplify_type { - typedef Value* SimpleType; - - static SimpleType getSimplifiedValue(const Use &Val) { - return (SimpleType)Val.get(); + /// getUnderlyingObject - This method strips off any GEP address adjustments + /// and pointer casts from the specified value, returning the original object + /// being addressed. Note that the returned value has pointer type if the + /// specified value does. + Value *getUnderlyingObject(); + const Value *getUnderlyingObject() const { + return const_cast(this)->getUnderlyingObject(); } -}; -template<> struct simplify_type { - typedef Value* SimpleType; - static SimpleType getSimplifiedValue(const Use &Val) { - return (SimpleType)Val.get(); + /// DoPHITranslation - If this value is a PHI node with CurBB as its parent, + /// return the value in the PHI node corresponding to PredBB. If not, return + /// ourself. This is useful if you want to know the value something has in a + /// predecessor block. + Value *DoPHITranslation(const BasicBlock *CurBB, const BasicBlock *PredBB); + + const Value *DoPHITranslation(const BasicBlock *CurBB, + const BasicBlock *PredBB) const{ + return const_cast(this)->DoPHITranslation(CurBB, PredBB); } }; +inline std::ostream &operator<<(std::ostream &OS, const Value &V) { + V.print(OS); + return OS; +} +inline raw_ostream &operator<<(raw_ostream &OS, const Value &V) { + V.print(OS); + return OS; +} + +void Use::set(Value *V) { + if (Val) removeFromList(); + Val = V; + if (V) V->addUse(*this); +} + + // isa - Provide some specializations of isa so that we don't have to include // the subtype header files to test to see if the value is a subclass... // -template <> inline bool isa_impl(const Value &Val) { - return Val.getValueType() == Value::TypeVal; +template <> inline bool isa_impl(const Value &Val) { + return Val.getValueID() >= Value::ConstantFirstVal && + Val.getValueID() <= Value::ConstantLastVal; +} +template <> inline bool isa_impl(const Value &Val) { + return Val.getValueID() == Value::ArgumentVal; } -template <> inline bool isa_impl(const Value &Val) { - return Val.getValueType() == Value::ConstantVal; +template <> inline bool isa_impl(const Value &Val) { + return Val.getValueID() == Value::InlineAsmVal; } -template <> inline bool isa_impl(const Value &Val) { - return Val.getValueType() == Value::ArgumentVal; +template <> inline bool isa_impl(const Value &Val) { + return Val.getValueID() >= Value::InstructionVal; } -template <> inline bool isa_impl(const Value &Val) { - return Val.getValueType() == Value::InstructionVal; +template <> inline bool isa_impl(const Value &Val) { + return Val.getValueID() == Value::BasicBlockVal; } -template <> inline bool isa_impl(const Value &Val) { - return Val.getValueType() == Value::BasicBlockVal; +template <> inline bool isa_impl(const Value &Val) { + return Val.getValueID() == Value::FunctionVal; } -template <> inline bool isa_impl(const Value &Val) { - return Val.getValueType() == Value::FunctionVal; +template <> inline bool isa_impl(const Value &Val) { + return Val.getValueID() == Value::GlobalVariableVal; } -template <> inline bool isa_impl(const Value &Val) { - return Val.getValueType() == Value::GlobalVariableVal; +template <> inline bool isa_impl(const Value &Val) { + return Val.getValueID() == Value::GlobalAliasVal; } -template <> inline bool isa_impl(const Value &Val) { - return isa(Val) || isa(Val); +template <> inline bool isa_impl(const Value &Val) { + return isa(Val) || isa(Val) || + isa(Val); } + + +// Value* is only 4-byte aligned. +template<> +class PointerLikeTypeTraits { + typedef Value* PT; +public: + static inline void *getAsVoidPointer(PT P) { return P; } + static inline PT getFromVoidPointer(void *P) { + return static_cast(P); + } + enum { NumLowBitsAvailable = 2 }; +}; + +} // End llvm namespace #endif