LLVM  4.0.0
UniqueVector.h
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1 //===-- llvm/ADT/UniqueVector.h ---------------------------------*- 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 #ifndef LLVM_ADT_UNIQUEVECTOR_H
11 #define LLVM_ADT_UNIQUEVECTOR_H
12 
13 #include <cassert>
14 #include <cstddef>
15 #include <map>
16 #include <vector>
17 
18 namespace llvm {
19 
20 //===----------------------------------------------------------------------===//
21 /// UniqueVector - This class produces a sequential ID number (base 1) for each
22 /// unique entry that is added. T is the type of entries in the vector. This
23 /// class should have an implementation of operator== and of operator<.
24 /// Entries can be fetched using operator[] with the entry ID.
25 template<class T> class UniqueVector {
26 public:
27  typedef typename std::vector<T> VectorType;
28  typedef typename VectorType::iterator iterator;
29  typedef typename VectorType::const_iterator const_iterator;
30 
31 private:
32  // Map - Used to handle the correspondence of entry to ID.
33  std::map<T, unsigned> Map;
34 
35  // Vector - ID ordered vector of entries. Entries can be indexed by ID - 1.
36  //
37  VectorType Vector;
38 
39 public:
40  /// insert - Append entry to the vector if it doesn't already exist. Returns
41  /// the entry's index + 1 to be used as a unique ID.
42  unsigned insert(const T &Entry) {
43  // Check if the entry is already in the map.
44  unsigned &Val = Map[Entry];
45 
46  // See if entry exists, if so return prior ID.
47  if (Val) return Val;
48 
49  // Compute ID for entry.
50  Val = static_cast<unsigned>(Vector.size()) + 1;
51 
52  // Insert in vector.
53  Vector.push_back(Entry);
54  return Val;
55  }
56 
57  /// idFor - return the ID for an existing entry. Returns 0 if the entry is
58  /// not found.
59  unsigned idFor(const T &Entry) const {
60  // Search for entry in the map.
61  typename std::map<T, unsigned>::const_iterator MI = Map.find(Entry);
62 
63  // See if entry exists, if so return ID.
64  if (MI != Map.end()) return MI->second;
65 
66  // No luck.
67  return 0;
68  }
69 
70  /// operator[] - Returns a reference to the entry with the specified ID.
71  ///
72  const T &operator[](unsigned ID) const {
73  assert(ID-1 < size() && "ID is 0 or out of range!");
74  return Vector[ID - 1];
75  }
76 
77  /// \brief Return an iterator to the start of the vector.
78  iterator begin() { return Vector.begin(); }
79 
80  /// \brief Return an iterator to the start of the vector.
81  const_iterator begin() const { return Vector.begin(); }
82 
83  /// \brief Return an iterator to the end of the vector.
84  iterator end() { return Vector.end(); }
85 
86  /// \brief Return an iterator to the end of the vector.
87  const_iterator end() const { return Vector.end(); }
88 
89  /// size - Returns the number of entries in the vector.
90  ///
91  size_t size() const { return Vector.size(); }
92 
93  /// empty - Returns true if the vector is empty.
94  ///
95  bool empty() const { return Vector.empty(); }
96 
97  /// reset - Clears all the entries.
98  ///
99  void reset() {
100  Map.clear();
101  Vector.resize(0, 0);
102  }
103 };
104 
105 } // End of namespace llvm
106 
107 #endif // LLVM_ADT_UNIQUEVECTOR_H
const T & operator[](unsigned ID) const
operator[] - Returns a reference to the entry with the specified ID.
Definition: UniqueVector.h:72
const_iterator begin() const
Return an iterator to the start of the vector.
Definition: UniqueVector.h:81
VectorType::iterator iterator
Definition: UniqueVector.h:28
VectorType::const_iterator const_iterator
Definition: UniqueVector.h:29
const_iterator end() const
Return an iterator to the end of the vector.
Definition: UniqueVector.h:87
unsigned idFor(const T &Entry) const
idFor - return the ID for an existing entry.
Definition: UniqueVector.h:59
std::vector< T > VectorType
Definition: UniqueVector.h:27
bool empty() const
empty - Returns true if the vector is empty.
Definition: UniqueVector.h:95
void reset()
reset - Clears all the entries.
Definition: UniqueVector.h:99
iterator begin()
Return an iterator to the start of the vector.
Definition: UniqueVector.h:78
iterator end()
Return an iterator to the end of the vector.
Definition: UniqueVector.h:84
unsigned insert(const T &Entry)
insert - Append entry to the vector if it doesn't already exist.
Definition: UniqueVector.h:42
size_t size() const
size - Returns the number of entries in the vector.
Definition: UniqueVector.h:91
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
IRTranslator LLVM IR MI
UniqueVector - This class produces a sequential ID number (base 1) for each unique entry that is adde...
Definition: UniqueVector.h:25