include/llvm/ADT/DenseSet.h

   1 //===- llvm/ADT/DenseSet.h - Dense probed hash table ------------*- 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 defines the DenseSet class.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef LLVM_ADT_DENSESET_H
  15 #define LLVM_ADT_DENSESET_H
  16
  17 #include "llvm/ADT/DenseMap.h"
  18
  19 namespace llvm {
  20
  21 /// DenseSet - This implements a dense probed hash-table based set.
  22 ///
  23 /// FIXME: This is currently implemented directly in terms of DenseMap, this
  24 /// should be optimized later if there is a need.
  25 template<typename ValueT, typename ValueInfoT = DenseMapInfo<ValueT> >
  26 class DenseSet {
  27   typedef DenseMap<ValueT, char, ValueInfoT> MapTy;
  28   MapTy TheMap;
  29 public:
  30   DenseSet(const DenseSet &Other) : TheMap(Other.TheMap) {}
  31   explicit DenseSet(unsigned NumInitBuckets = 64) : TheMap(NumInitBuckets) {}
  32
  33   bool empty() const { return TheMap.empty(); }
  34   unsigned size() const { return TheMap.size(); }
  35
  36   /// Grow the denseset so that it has at least Size buckets. Does not shrink
  37   void resize(size_t Size) { TheMap.resize(Size); }
  38
  39   void clear() {
  40     TheMap.clear();
  41   }
  42
  43   bool count(const ValueT &V) const {
  44     return TheMap.count(V);
  45   }
  46
  47   bool erase(const ValueT &V) {
  48     return TheMap.erase(V);
  49   }
  50
  51   void swap(DenseSet& RHS) {
  52     TheMap.swap(RHS.TheMap);
  53   }
  54
  55   DenseSet &operator=(const DenseSet &RHS) {
  56     TheMap = RHS.TheMap;
  57     return *this;
  58   }
  59
  60   // Iterators.
  61
  62   class Iterator {
  63     typename MapTy::iterator I;
  64     friend class DenseSet;
  65   public:
  66     typedef typename MapTy::iterator::difference_type difference_type;
  67     typedef ValueT value_type;
  68     typedef value_type *pointer;
  69     typedef value_type &reference;
  70     typedef std::forward_iterator_tag iterator_category;
  71
  72     Iterator(const typename MapTy::iterator &i) : I(i) {}
  73
  74     ValueT& operator*() { return I->first; }
  75     ValueT* operator->() { return &I->first; }
  76
  77     Iterator& operator++() { ++I; return *this; }
  78     bool operator==(const Iterator& X) const { return I == X.I; }
  79     bool operator!=(const Iterator& X) const { return I != X.I; }
  80   };
  81
  82   class ConstIterator {
  83     typename MapTy::const_iterator I;
  84     friend class DenseSet;
  85   public:
  86     typedef typename MapTy::const_iterator::difference_type difference_type;
  87     typedef ValueT value_type;
  88     typedef value_type *pointer;
  89     typedef value_type &reference;
  90     typedef std::forward_iterator_tag iterator_category;
  91
  92     ConstIterator(const typename MapTy::const_iterator &i) : I(i) {}
  93
  94     const ValueT& operator*() { return I->first; }
  95     const ValueT* operator->() { return &I->first; }
  96
  97     ConstIterator& operator++() { ++I; return *this; }
  98     bool operator==(const ConstIterator& X) const { return I == X.I; }
  99     bool operator!=(const ConstIterator& X) const { return I != X.I; }
 100   };
 101
 102   typedef Iterator      iterator;
 103   typedef ConstIterator const_iterator;
 104
 105   iterator begin() { return Iterator(TheMap.begin()); }
 106   iterator end() { return Iterator(TheMap.end()); }
 107
 108   const_iterator begin() const { return ConstIterator(TheMap.begin()); }
 109   const_iterator end() const { return ConstIterator(TheMap.end()); }
 110
 111   iterator find(const ValueT &V) { return Iterator(TheMap.find(V)); }
 112   void erase(Iterator I) { return TheMap.erase(I.I); }
 113   void erase(ConstIterator CI) { return TheMap.erase(CI.I); }
 114
 115   std::pair<iterator, bool> insert(const ValueT &V) {
 116     return TheMap.insert(std::make_pair(V, 0));
 117   }
 118
 119   // Range insertion of values.
 120   template<typename InputIt>
 121   void insert(InputIt I, InputIt E) {
 122     for (; I != E; ++I)
 123       insert(*I);
 124   }
 125 };
 126
 127 } // end namespace llvm
 128
 129 #endif