LLVM  6.0.0svn
UniqueVector.h
Go to the documentation of this file.
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  using VectorType = typename std::vector<T>;
28  using iterator = typename VectorType::iterator;
29  using const_iterator = typename VectorType::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  VectorType Vector;
37 
38 public:
39  /// insert - Append entry to the vector if it doesn't already exist. Returns
40  /// the entry's index + 1 to be used as a unique ID.
41  unsigned insert(const T &Entry) {
42  // Check if the entry is already in the map.
43  unsigned &Val = Map[Entry];
44 
45  // See if entry exists, if so return prior ID.
46  if (Val) return Val;
47 
48  // Compute ID for entry.
49  Val = static_cast<unsigned>(Vector.size()) + 1;
50 
51  // Insert in vector.
52  Vector.push_back(Entry);
53  return Val;
54  }
55 
56  /// idFor - return the ID for an existing entry. Returns 0 if the entry is
57  /// not found.
58  unsigned idFor(const T &Entry) const {
59  // Search for entry in the map.
60  typename std::map<T, unsigned>::const_iterator MI = Map.find(Entry);
61 
62  // See if entry exists, if so return ID.
63  if (MI != Map.end()) return MI->second;
64 
65  // No luck.
66  return 0;
67  }
68 
69  /// operator[] - Returns a reference to the entry with the specified ID.
70  const T &operator[](unsigned ID) const {
71  assert(ID-1 < size() && "ID is 0 or out of range!");
72  return Vector[ID - 1];
73  }
74 
75  /// \brief Return an iterator to the start of the vector.
76  iterator begin() { return Vector.begin(); }
77 
78  /// \brief Return an iterator to the start of the vector.
79  const_iterator begin() const { return Vector.begin(); }
80 
81  /// \brief Return an iterator to the end of the vector.
82  iterator end() { return Vector.end(); }
83 
84  /// \brief Return an iterator to the end of the vector.
85  const_iterator end() const { return Vector.end(); }
86 
87  /// size - Returns the number of entries in the vector.
88  size_t size() const { return Vector.size(); }
89 
90  /// empty - Returns true if the vector is empty.
91  bool empty() const { return Vector.empty(); }
92 
93  /// reset - Clears all the entries.
94  void reset() {
95  Map.clear();
96  Vector.resize(0, 0);
97  }
98 };
99 
100 } // end namespace llvm
101 
102 #endif // LLVM_ADT_UNIQUEVECTOR_H
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
typename std::vector< std::string > VectorType
Definition: UniqueVector.h:27
const T & operator[](unsigned ID) const
operator[] - Returns a reference to the entry with the specified ID.
Definition: UniqueVector.h:70
bool empty() const
empty - Returns true if the vector is empty.
Definition: UniqueVector.h:91
unsigned idFor(const T &Entry) const
idFor - return the ID for an existing entry.
Definition: UniqueVector.h:58
const_iterator end() const
Return an iterator to the end of the vector.
Definition: UniqueVector.h:85
typename VectorType::const_iterator const_iterator
Definition: UniqueVector.h:29
typename VectorType::iterator iterator
Definition: UniqueVector.h:28
void reset()
reset - Clears all the entries.
Definition: UniqueVector.h:94
iterator begin()
Return an iterator to the start of the vector.
Definition: UniqueVector.h:76
size_t size() const
size - Returns the number of entries in the vector.
Definition: UniqueVector.h:88
const_iterator begin() const
Return an iterator to the start of the vector.
Definition: UniqueVector.h:79
iterator end()
Return an iterator to the end of the vector.
Definition: UniqueVector.h:82
unsigned insert(const T &Entry)
insert - Append entry to the vector if it doesn&#39;t already exist.
Definition: UniqueVector.h:41
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