LLVM  6.0.0svn
InstIterator.h
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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 
23 #include "llvm/IR/BasicBlock.h"
24 #include "llvm/IR/Function.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>
55  : BBs(II.BBs), BB(II.BB), BI(II.BI) {}
56 
57  template<typename A, typename B, typename C, typename D>
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 
88  ++BI;
89  advanceToNextBB();
90  return *this;
91  }
92  inline InstIterator operator++(int) {
93  InstIterator tmp = *this; ++*this; return tmp;
94  }
95 
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 =
125 using const_inst_iterator =
128  const Instruction>;
131 
133 inline inst_iterator inst_end(Function *F) { return inst_iterator(*F, true); }
135  return inst_range(inst_begin(F), inst_end(F));
136 }
138  return const_inst_iterator(*F);
139 }
141  return const_inst_iterator(*F, true);
142 }
144  return const_inst_range(inst_begin(F), inst_end(F));
145 }
147 inline inst_iterator inst_end(Function &F) { return inst_iterator(F, true); }
149  return inst_range(inst_begin(F), inst_end(F));
150 }
152  return const_inst_iterator(F);
153 }
155  return const_inst_iterator(F, true);
156 }
158  return const_inst_range(inst_begin(F), inst_end(F));
159 }
160 
161 } // end namespace llvm
162 
163 #endif // LLVM_IR_INSTITERATOR_H
const_iterator end(StringRef path)
Get end iterator over path.
Definition: Path.cpp:244
const_iterator begin(StringRef path, Style style=Style::native)
Get begin iterator over path.
Definition: Path.cpp:235
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
bool operator!=(const InstIterator &y) const
Definition: InstIterator.h:83
InstIterator operator++(int)
Definition: InstIterator.h:92
This provides a very simple, boring adaptor for a begin and end iterator into a range type...
bool operator==(const InstIterator &y) const
Definition: InstIterator.h:80
InstIterator & operator++()
Definition: InstIterator.h:87
F(f)
reference operator*() const
Definition: InstIterator.h:77
InstListType::const_iterator const_iterator
Definition: BasicBlock.h:92
inst_iterator inst_begin(Function *F)
Definition: InstIterator.h:132
InstIterator< SymbolTableList< BasicBlock >, Function::iterator, BasicBlock::iterator, Instruction > inst_iterator
Definition: InstIterator.h:124
InstIterator(InstIterator< A, B, C, D > &II)
Definition: InstIterator.h:58
BasicBlockListType::iterator iterator
Definition: Function.h:65
InstIterator & operator--()
Definition: InstIterator.h:96
BasicBlockListType::const_iterator const_iterator
Definition: Function.h:66
bool atEnd() const
Definition: InstIterator.h:108
BBIty & getBasicBlockIterator()
Definition: InstIterator.h:74
InstIterator()=default
InstIterator< const SymbolTableList< BasicBlock >, Function::const_iterator, BasicBlock::const_iterator, const Instruction > const_inst_iterator
Definition: InstIterator.h:128
BIty & getInstructionIterator()
Definition: InstIterator.h:75
InstIterator(M &m, bool)
Definition: InstIterator.h:69
std::bidirectional_iterator_tag iterator_category
Definition: InstIterator.h:43
A range adaptor for a pair of iterators.
InstListType::iterator iterator
Instruction iterators...
Definition: BasicBlock.h:91
iterator_range< inst_iterator > inst_range
Definition: InstIterator.h:129
InstIterator operator--(int)
Definition: InstIterator.h:104
iterator_range< const_inst_iterator > const_inst_range
Definition: InstIterator.h:130
inst_range instructions(Function *F)
Definition: InstIterator.h:134
inst_iterator inst_end(Function *F)
Definition: InstIterator.h:133
InstIterator(const InstIterator< A, B, C, D > &II)
Definition: InstIterator.h:54
pointer operator->() const
Definition: InstIterator.h:78