1 //===- InstIterator.h - Classes for inst iteration --------------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file contains definitions of two iterators for iterating over the 11 // instructions in a function. This is effectively a wrapper around a two level 12 // iterator that can probably be genericized later. 13 // 14 // Note that this iterator gets invalidated any time that basic blocks or 15 // instructions are moved around. 16 // 17 //===----------------------------------------------------------------------===// 18 19 #ifndef LLVM_IR_INSTITERATOR_H 20 #define LLVM_IR_INSTITERATOR_H 21 22 #include "llvm/IR/BasicBlock.h" 23 #include "llvm/IR/Function.h" 24 25 namespace llvm { 26 27 // This class implements inst_begin() & inst_end() for 28 // inst_iterator and const_inst_iterator's. 29 // 30 template <class _BB_t, class _BB_i_t, class _BI_t, class _II_t> 31 class InstIterator { 32 typedef _BB_t BBty; 33 typedef _BB_i_t BBIty; 34 typedef _BI_t BIty; 35 typedef _II_t IIty; 36 _BB_t *BBs; // BasicBlocksType 37 _BB_i_t BB; // BasicBlocksType::iterator 38 _BI_t BI; // BasicBlock::iterator 39 public: 40 typedef std::bidirectional_iterator_tag iterator_category; 41 typedef IIty value_type; 42 typedef signed difference_type; 43 typedef IIty* pointer; 44 typedef IIty& reference; 45 46 // Default constructor 47 InstIterator() {} 48 49 // Copy constructor... 50 template<typename A, typename B, typename C, typename D> 51 InstIterator(const InstIterator<A,B,C,D> &II) 52 : BBs(II.BBs), BB(II.BB), BI(II.BI) {} 53 54 template<typename A, typename B, typename C, typename D> 55 InstIterator(InstIterator<A,B,C,D> &II) 56 : BBs(II.BBs), BB(II.BB), BI(II.BI) {} 57 58 template<class M> InstIterator(M &m) 59 : BBs(&m.getBasicBlockList()), BB(BBs->begin()) { // begin ctor 60 if (BB != BBs->end()) { 61 BI = BB->begin(); 62 advanceToNextBB(); 63 } 64 } 65 66 template<class M> InstIterator(M &m, bool) 67 : BBs(&m.getBasicBlockList()), BB(BBs->end()) { // end ctor 68 } 69 70 // Accessors to get at the underlying iterators... 71 inline BBIty &getBasicBlockIterator() { return BB; } 72 inline BIty &getInstructionIterator() { return BI; } 73 74 inline reference operator*() const { return *BI; } 75 inline pointer operator->() const { return &operator*(); } 76 77 inline bool operator==(const InstIterator &y) const { 78 return BB == y.BB && (BB == BBs->end() || BI == y.BI); 79 } 80 inline bool operator!=(const InstIterator& y) const { 81 return !operator==(y); 82 } 83 84 InstIterator& operator++() { 85 ++BI; 86 advanceToNextBB(); 87 return *this; 88 } 89 inline InstIterator operator++(int) { 90 InstIterator tmp = *this; ++*this; return tmp; 91 } 92 93 InstIterator& operator--() { 94 while (BB == BBs->end() || BI == BB->begin()) { 95 --BB; 96 BI = BB->end(); 97 } 98 --BI; 99 return *this; 100 } 101 inline InstIterator operator--(int) { 102 InstIterator tmp = *this; --*this; return tmp; 103 } 104 105 inline bool atEnd() const { return BB == BBs->end(); } 106 107 private: 108 inline void advanceToNextBB() { 109 // The only way that the II could be broken is if it is now pointing to 110 // the end() of the current BasicBlock and there are successor BBs. 111 while (BI == BB->end()) { 112 ++BB; 113 if (BB == BBs->end()) break; 114 BI = BB->begin(); 115 } 116 } 117 }; 118 119 120 typedef InstIterator<iplist<BasicBlock>, 121 Function::iterator, BasicBlock::iterator, 122 Instruction> inst_iterator; 123 typedef InstIterator<const iplist<BasicBlock>, 124 Function::const_iterator, 125 BasicBlock::const_iterator, 126 const Instruction> const_inst_iterator; 127 128 inline inst_iterator inst_begin(Function *F) { return inst_iterator(*F); } 129 inline inst_iterator inst_end(Function *F) { return inst_iterator(*F, true); } 130 inline const_inst_iterator inst_begin(const Function *F) { 131 return const_inst_iterator(*F); 132 } 133 inline const_inst_iterator inst_end(const Function *F) { 134 return const_inst_iterator(*F, true); 135 } 136 inline inst_iterator inst_begin(Function &F) { return inst_iterator(F); } 137 inline inst_iterator inst_end(Function &F) { return inst_iterator(F, true); } 138 inline const_inst_iterator inst_begin(const Function &F) { 139 return const_inst_iterator(F); 140 } 141 inline const_inst_iterator inst_end(const Function &F) { 142 return const_inst_iterator(F, true); 143 } 144 145 } // End llvm namespace 146 147 #endif 148