X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FValue.h;h=7e7b415ffdeed671b1ba2ec26cf13a283633a236;hb=4b938958bcc59586508bc9681e75c2e3f5164672;hp=2aed4d2f503a24c3c449faa2054a1ede9b2bc4f7;hpb=530036b5e89e41787056120666bf0128ea8addd8;p=oota-llvm.git diff --git a/include/llvm/Value.h b/include/llvm/Value.h index 2aed4d2f503..7e7b415ffde 100644 --- a/include/llvm/Value.h +++ b/include/llvm/Value.h @@ -1,16 +1,13 @@ //===-- llvm/Value.h - Definition of the Value class ------------*- 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 is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. // -// This file defines the very important Value class. This is subclassed by a -// bunch of other important classes, like Instruction, Function, Type, etc... +//===----------------------------------------------------------------------===// // -// This file also defines the Use<> template for users of value. +// This file declares the Value class. // //===----------------------------------------------------------------------===// @@ -20,6 +17,7 @@ #include "llvm/AbstractTypeUser.h" #include "llvm/Use.h" #include "llvm/Support/Casting.h" +#include #include namespace llvm { @@ -27,55 +25,119 @@ namespace llvm { class Constant; class Argument; class Instruction; -struct BasicBlock; +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. +/// +/// 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: - unsigned SubclassID; // Subclass identifier (for isa/dyn_cast) - PATypeHolder Ty; - iplist Uses; - std::string Name; + 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, unsigned scid, const std::string &name = ""); + Value(const Type *Ty, unsigned scid); virtual ~Value(); - + /// dump - Support for debugging, callable in GDB: V->dump() // 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.empty(); } - inline const std::string &getName() const { return Name; } + inline bool hasName() const { return Name != 0; } + ValueName *getValueName() const { return 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(); } + + /// 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. - virtual void setName(const std::string &name, SymbolTable * = 0) { - Name = name; - } + /// 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); @@ -84,102 +146,148 @@ public: // Only use when in type resolution situations! void uncheckedReplaceAllUsesWith(Value *V); + /// 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 UseListIteratorWrapper use_iterator; - typedef UseListConstIteratorWrapper use_const_iterator; - - unsigned use_size() const { return Uses.size(); } - bool use_empty() const { return Uses.empty(); } - use_iterator use_begin() { return Uses.begin(); } - use_const_iterator use_begin() const { return Uses.begin(); } - use_iterator use_end() { return Uses.end(); } - use_const_iterator use_end() const { return Uses.end(); } - User *use_back() { return Uses.back().getUser(); } - const User *use_back() const { return Uses.back().getUser(); } + typedef value_use_iterator use_iterator; + typedef value_use_iterator use_const_iterator; + + 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(); } /// 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 { - iplist::const_iterator I = Uses.begin(), E = Uses.end(); + use_const_iterator I = use_begin(), E = use_end(); if (I == E) return false; return ++I == E; } - /// addUse/killUse - These two methods should only be used by the Use class. + /// hasNUses - Return true if this Value has exactly N users. /// - void addUse(Use &U) { Uses.push_back(&U); } - void killUse(Use &U) { Uses.remove(&U); } + bool hasNUses(unsigned N) const; - /// getValueType - 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 - /// starting with the InstructionVal value, the value stored is actually the - /// Instruction opcode, so there are more than just these values possible here - /// (and Instruction must be last). + /// hasNUsesOrMore - Return true if this value has N users or more. This is + /// logically equivalent to getNumUses() >= N. /// + bool hasNUsesOrMore(unsigned N) const; + + bool isUsedInBasicBlock(const BasicBlock *BB) const; + + /// 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; + + /// 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 - SimpleConstantVal, // This is some other type of Constant + 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 - ValueListVal // This is for bcreader, a special ValTy + + // Markers: + ConstantFirstVal = FunctionVal, + ConstantLastVal = MDNodeVal }; - unsigned getValueType() const { + + /// 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; } // Methods for support type inquiry through isa, cast, and dyn_cast: - static inline bool classof(const Value *V) { + static inline bool classof(const Value *) { return true; // Values are always values. } /// getRawType - This should only be used to implement the vmcore library. /// - const Type *getRawType() const { return Ty.getRawType(); } + const Type *getRawType() const { return VTy.getRawType(); } + + /// 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(); + } -private: - /// FIXME: this is a gross hack, needed by another gross hack. Eliminate! - void setValueType(unsigned VT) { SubclassID = VT; } - friend class Instruction; + /// 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(); + } + + /// 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 User *UseListIteratorWrapper::operator*() const { - return Super::operator*().getUser(); -} - -inline const User *UseListConstIteratorWrapper::operator*() const { - return Super::operator*().getUser(); -} - - -Use::Use(Value *v, User *user) : Val(v), U(user) { - if (Val) Val->addUse(*this); -} - -Use::Use(const Use &u) : Val(u.Val), U(u.U) { - if (Val) Val->addUse(*this); -} - -Use::~Use() { - if (Val) Val->killUse(*this); +inline raw_ostream &operator<<(raw_ostream &OS, const Value &V) { + V.print(OS); + return OS; } - -void Use::set(Value *V) { - if (Val) Val->killUse(*this); + +void Use::set(Value *V) { + if (Val) removeFromList(); Val = V; if (V) V->addUse(*this); } @@ -188,31 +296,48 @@ void Use::set(Value *V) { // 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::ConstantExprVal || - Val.getValueType() == Value::SimpleConstantVal || - Val.getValueType() == Value::ConstantAggregateZeroVal || - Val.getValueType() == Value::FunctionVal || - Val.getValueType() == Value::GlobalVariableVal; +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.getValueType() == Value::ArgumentVal; +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::InstructionVal; +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::BasicBlockVal; +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::FunctionVal; +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::GlobalVariableVal; +template <> inline bool isa_impl(const Value &Val) { + return Val.getValueID() == Value::FunctionVal; } -template <> inline bool isa_impl(const Value &Val) { - return isa(Val) || isa(Val); +template <> inline bool isa_impl(const Value &Val) { + return Val.getValueID() == 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) || + 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