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/ADT/iterator_range.h" 23 #include "llvm/IR/BasicBlock.h" 24 #include "llvm/IR/Function.h" 25 #include "llvm/IR/SymbolTableListTraits.h" 26 #include <iterator> 27 28 namespace llvm { 29 30 // This class implements inst_begin() & inst_end() for 31 // inst_iterator and const_inst_iterator's. 32 // 33 template <class BB_t, class BB_i_t, class BI_t, class II_t> class InstIterator { 34 using BBty = BB_t; 35 using BBIty = BB_i_t; 36 using BIty = BI_t; 37 using IIty = II_t; 38 BB_t *BBs; // BasicBlocksType 39 BB_i_t BB; // BasicBlocksType::iterator 40 BI_t BI; // BasicBlock::iterator 41 42 public: 43 using iterator_category = std::bidirectional_iterator_tag; 44 using value_type = IIty; 45 using difference_type = signed; 46 using pointer = IIty *; 47 using reference = IIty &; 48 49 // Default constructor 50 InstIterator() = default; 51 52 // Copy constructor... 53 template<typename A, typename B, typename C, typename D> 54 InstIterator(const InstIterator<A,B,C,D> &II) 55 : BBs(II.BBs), BB(II.BB), BI(II.BI) {} 56 57 template<typename A, typename B, typename C, typename D> 58 InstIterator(InstIterator<A,B,C,D> &II) 59 : BBs(II.BBs), BB(II.BB), BI(II.BI) {} 60 61 template<class M> InstIterator(M &m) 62 : BBs(&m.getBasicBlockList()), BB(BBs->begin()) { // begin ctor 63 if (BB != BBs->end()) { 64 BI = BB->begin(); 65 advanceToNextBB(); 66 } 67 } 68 69 template<class M> InstIterator(M &m, bool) 70 : BBs(&m.getBasicBlockList()), BB(BBs->end()) { // end ctor 71 } 72 73 // Accessors to get at the underlying iterators... 74 inline BBIty &getBasicBlockIterator() { return BB; } 75 inline BIty &getInstructionIterator() { return BI; } 76 77 inline reference operator*() const { return *BI; } 78 inline pointer operator->() const { return &operator*(); } 79 80 inline bool operator==(const InstIterator &y) const { 81 return BB == y.BB && (BB == BBs->end() || BI == y.BI); 82 } 83 inline bool operator!=(const InstIterator& y) const { 84 return !operator==(y); 85 } 86 87 InstIterator& operator++() { 88 ++BI; 89 advanceToNextBB(); 90 return *this; 91 } 92 inline InstIterator operator++(int) { 93 InstIterator tmp = *this; ++*this; return tmp; 94 } 95 96 InstIterator& operator--() { 97 while (BB == BBs->end() || BI == BB->begin()) { 98 --BB; 99 BI = BB->end(); 100 } 101 --BI; 102 return *this; 103 } 104 inline InstIterator operator--(int) { 105 InstIterator tmp = *this; --*this; return tmp; 106 } 107 108 inline bool atEnd() const { return BB == BBs->end(); } 109 110 private: 111 inline void advanceToNextBB() { 112 // The only way that the II could be broken is if it is now pointing to 113 // the end() of the current BasicBlock and there are successor BBs. 114 while (BI == BB->end()) { 115 ++BB; 116 if (BB == BBs->end()) break; 117 BI = BB->begin(); 118 } 119 } 120 }; 121 122 using inst_iterator = 123 InstIterator<SymbolTableList<BasicBlock>, Function::iterator, 124 BasicBlock::iterator, Instruction>; 125 using const_inst_iterator = 126 InstIterator<const SymbolTableList<BasicBlock>, 127 Function::const_iterator, BasicBlock::const_iterator, 128 const Instruction>; 129 using inst_range = iterator_range<inst_iterator>; 130 using const_inst_range = iterator_range<const_inst_iterator>; 131 132 inline inst_iterator inst_begin(Function *F) { return inst_iterator(*F); } 133 inline inst_iterator inst_end(Function *F) { return inst_iterator(*F, true); } 134 inline inst_range instructions(Function *F) { 135 return inst_range(inst_begin(F), inst_end(F)); 136 } 137 inline const_inst_iterator inst_begin(const Function *F) { 138 return const_inst_iterator(*F); 139 } 140 inline const_inst_iterator inst_end(const Function *F) { 141 return const_inst_iterator(*F, true); 142 } 143 inline const_inst_range instructions(const Function *F) { 144 return const_inst_range(inst_begin(F), inst_end(F)); 145 } 146 inline inst_iterator inst_begin(Function &F) { return inst_iterator(F); } 147 inline inst_iterator inst_end(Function &F) { return inst_iterator(F, true); } 148 inline inst_range instructions(Function &F) { 149 return inst_range(inst_begin(F), inst_end(F)); 150 } 151 inline const_inst_iterator inst_begin(const Function &F) { 152 return const_inst_iterator(F); 153 } 154 inline const_inst_iterator inst_end(const Function &F) { 155 return const_inst_iterator(F, true); 156 } 157 inline const_inst_range instructions(const Function &F) { 158 return const_inst_range(inst_begin(F), inst_end(F)); 159 } 160 161 } // end namespace llvm 162 163 #endif // LLVM_IR_INSTITERATOR_H 164
