Function.h revision 697954c15da58bd8b186dbafdedd8b06db770201
1//===-- llvm/Method.h - Class to represent a single VM method ----*- C++ -*--=// 2// 3// This file contains the declaration of the Method class, which represents a 4// single Method/function/procedure in the VM. 5// 6// Note that basic blocks themselves are Def's, because they are referenced 7// by instructions like calls and can go in virtual function tables and stuff. 8// 9//===----------------------------------------------------------------------===// 10 11#ifndef LLVM_METHOD_H 12#define LLVM_METHOD_H 13 14#include "llvm/SymTabValue.h" 15#include "llvm/BasicBlock.h" 16#include "llvm/GlobalValue.h" 17 18class Instruction; 19class BasicBlock; 20class MethodArgument; 21class MethodType; 22class Module; 23 24class Method : public GlobalValue, public SymTabValue { 25public: 26 typedef ValueHolder<MethodArgument, Method, Method> ArgumentListType; 27 typedef ValueHolder<BasicBlock , Method, Method> BasicBlocksType; 28 29 // BasicBlock iterators... 30 typedef BasicBlocksType::iterator iterator; 31 typedef BasicBlocksType::const_iterator const_iterator; 32 typedef std::reverse_iterator<const_iterator> const_reverse_iterator; 33 typedef std::reverse_iterator<iterator> reverse_iterator; 34 35private: 36 37 // Important things that make up a method! 38 BasicBlocksType BasicBlocks; // The basic blocks 39 ArgumentListType ArgumentList; // The formal arguments 40 41 friend class ValueHolder<Method, Module, Module>; 42 void setParent(Module *parent); 43 44public: 45 Method(const MethodType *Ty, bool isInternal, const std::string &Name = ""); 46 ~Method(); 47 48 // Specialize setName to handle symbol table majik... 49 virtual void setName(const std::string &name, SymbolTable *ST = 0); 50 51 const Type *getReturnType() const; // Return the return type of method 52 const MethodType *getMethodType() const; // Return the MethodType for me 53 54 // Is the body of this method unknown? (the basic block list is empty if so) 55 // this is true for external methods, defined as forward "declare"ations 56 bool isExternal() const { return BasicBlocks.empty(); } 57 58 // Get the underlying elements of the Method... both the argument list and 59 // basic block list are empty for external methods. 60 // 61 inline const ArgumentListType &getArgumentList() const{ return ArgumentList; } 62 inline ArgumentListType &getArgumentList() { return ArgumentList; } 63 64 inline const BasicBlocksType &getBasicBlocks() const { return BasicBlocks; } 65 inline BasicBlocksType &getBasicBlocks() { return BasicBlocks; } 66 67 inline const BasicBlock *getEntryNode() const { return front(); } 68 inline BasicBlock *getEntryNode() { return front(); } 69 70 //===--------------------------------------------------------------------===// 71 // BasicBlock iterator forwarding functions 72 // 73 inline iterator begin() { return BasicBlocks.begin(); } 74 inline const_iterator begin() const { return BasicBlocks.begin(); } 75 inline iterator end () { return BasicBlocks.end(); } 76 inline const_iterator end () const { return BasicBlocks.end(); } 77 78 inline reverse_iterator rbegin() { return BasicBlocks.rbegin(); } 79 inline const_reverse_iterator rbegin() const { return BasicBlocks.rbegin(); } 80 inline reverse_iterator rend () { return BasicBlocks.rend(); } 81 inline const_reverse_iterator rend () const { return BasicBlocks.rend(); } 82 83 inline unsigned size() const { return BasicBlocks.size(); } 84 inline bool empty() const { return BasicBlocks.empty(); } 85 inline const BasicBlock *front() const { return BasicBlocks.front(); } 86 inline BasicBlock *front() { return BasicBlocks.front(); } 87 inline const BasicBlock *back() const { return BasicBlocks.back(); } 88 inline BasicBlock *back() { return BasicBlocks.back(); } 89 90 91 // Methods for support type inquiry through isa, cast, and dyn_cast: 92 static inline bool classof(const Method *T) { return true; } 93 static inline bool classof(const Value *V) { 94 return V->getValueType() == Value::MethodVal; 95 } 96 97 // dropAllReferences() - This function causes all the subinstructions to "let 98 // go" of all references that they are maintaining. This allows one to 99 // 'delete' a whole class at a time, even though there may be circular 100 // references... first all references are dropped, and all use counts go to 101 // zero. Then everything is delete'd for real. Note that no operations are 102 // valid on an object that has "dropped all references", except operator 103 // delete. 104 // 105 void dropAllReferences(); 106 107 //===--------------------------------------------------------------------===// 108 // Method Instruction iterator code 109 //===--------------------------------------------------------------------===// 110 // 111 template <class _BB_t, class _BB_i_t, class _BI_t, class _II_t> 112 class InstIterator; 113 typedef InstIterator<BasicBlocksType, iterator, 114 BasicBlock::iterator, Instruction*> inst_iterator; 115 typedef InstIterator<const BasicBlocksType, const_iterator, 116 BasicBlock::const_iterator, 117 const Instruction*> const_inst_iterator; 118 119 // This inner class is used to implement inst_begin() & inst_end() for 120 // inst_iterator and const_inst_iterator's. 121 // 122 template <class _BB_t, class _BB_i_t, class _BI_t, class _II_t> 123 class InstIterator { 124 typedef _BB_t BBty; 125 typedef _BB_i_t BBIty; 126 typedef _BI_t BIty; 127 typedef _II_t IIty; 128 _BB_t &BBs; // BasicBlocksType 129 _BB_i_t BB; // BasicBlocksType::iterator 130 _BI_t BI; // BasicBlock::iterator 131 public: 132 typedef std::bidirectional_iterator_tag iterator_category; 133 typedef IIty value_type; 134 typedef unsigned difference_type; 135 typedef BIty pointer; 136 typedef IIty reference; 137 138 template<class M> InstIterator(M &m) 139 : BBs(m.getBasicBlocks()), BB(BBs.begin()) { // begin ctor 140 if (BB != BBs.end()) { 141 BI = (*BB)->begin(); 142 resyncInstructionIterator(); 143 } 144 } 145 146 template<class M> InstIterator(M &m, bool) 147 : BBs(m.getBasicBlocks()), BB(BBs.end()) { // end ctor 148 } 149 150 // Accessors to get at the underlying iterators... 151 inline BBIty &getBasicBlockIterator() { return BB; } 152 inline BIty &getInstructionIterator() { return BI; } 153 154 inline IIty operator*() const { return *BI; } 155 inline IIty operator->() const { return operator*(); } 156 157 inline bool operator==(const InstIterator &y) const { 158 return BB == y.BB && (BB == BBs.end() || BI == y.BI); 159 } 160 inline bool operator!=(const InstIterator& y) const { 161 return !operator==(y); 162 } 163 164 // resyncInstructionIterator - This should be called if the 165 // InstructionIterator is modified outside of our control. This resynchs 166 // the internals of the InstIterator to a consistent state. 167 // 168 inline void resyncInstructionIterator() { 169 // The only way that the II could be broken is if it is now pointing to 170 // the end() of the current BasicBlock and there are successor BBs. 171 while (BI == (*BB)->end()) { 172 ++BB; 173 if (BB == BBs.end()) break; 174 BI = (*BB)->begin(); 175 } 176 } 177 178 InstIterator& operator++() { 179 ++BI; 180 resyncInstructionIterator(); // Make sure it is still valid. 181 return *this; 182 } 183 inline InstIterator operator++(int) { 184 InstIterator tmp = *this; ++*this; return tmp; 185 } 186 187 InstIterator& operator--() { 188 while (BB == BBs.end() || BI == (*BB)->begin()) { 189 --BB; 190 BI = (*BB)->end(); 191 } 192 --BI; 193 return *this; 194 } 195 inline InstIterator operator--(int) { 196 InstIterator tmp = *this; --*this; return tmp; 197 } 198 199 inline bool atEnd() const { return BB == BBs.end(); } 200 }; 201 202 inline inst_iterator inst_begin() { return inst_iterator(*this); } 203 inline inst_iterator inst_end() { return inst_iterator(*this, true); } 204 inline const_inst_iterator inst_begin() const { return const_inst_iterator(*this); } 205 inline const_inst_iterator inst_end() const { return const_inst_iterator(*this, true); } 206}; 207 208// Provide specializations of GraphTraits to be able to treat a method as a 209// graph of basic blocks... these are the same as the basic block iterators, 210// except that the root node is implicitly the first node of the method. 211// 212template <> struct GraphTraits<Method*> : public GraphTraits<BasicBlock*> { 213 static NodeType *getEntryNode(Method *M) { return M->front(); } 214}; 215template <> struct GraphTraits<const Method*> : 216 public GraphTraits<const BasicBlock*> { 217 static NodeType *getEntryNode(const Method *M) { return M->front(); } 218}; 219 220// Provide specializations of GraphTraits to be able to treat a method as a 221// graph of basic blocks... and to walk it in inverse order. Inverse order for 222// a method is considered to be when traversing the predecessor edges of a BB 223// instead of the successor edges. 224// 225template <> struct GraphTraits<Inverse<Method*> > : 226 public GraphTraits<Inverse<BasicBlock*> > { 227 static NodeType *getEntryNode(Inverse<Method *> G) { return G.Graph->front();} 228}; 229template <> struct GraphTraits<Inverse<const Method*> > : 230 public GraphTraits<Inverse<const BasicBlock*> > { 231 static NodeType *getEntryNode(Inverse<const Method *> G) { 232 return G.Graph->front(); 233 } 234}; 235 236#endif 237