1 /* A type-safe hash set.
2    Copyright (C) 2014-2016 Free Software Foundation, Inc.
3 
4 This file is part of GCC.
5 
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10 
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 for more details.
15 
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3.  If not see
18 <http://www.gnu.org/licenses/>.  */
19 
20 
21 #ifndef hash_set_h
22 #define hash_set_h
23 
24 template<typename KeyId, typename Traits = default_hash_traits<KeyId> >
25 class hash_set
26 {
27 public:
28   typedef typename Traits::value_type Key;
29   explicit hash_set (size_t n = 13, bool ggc = false CXX_MEM_STAT_INFO)
m_table(n,ggc,GATHER_STATISTICS,HASH_SET_ORIGIN PASS_MEM_STAT)30     : m_table (n, ggc, GATHER_STATISTICS, HASH_SET_ORIGIN PASS_MEM_STAT) {}
31 
32   /* Create a hash_set in gc memory with space for at least n elements.  */
33 
34   static hash_set *
create_ggc(size_t n)35     create_ggc (size_t n)
36       {
37 	hash_set *set = ggc_alloc<hash_set> ();
38 	new (set) hash_set (n, true);
39 	return set;
40       }
41 
42   /* If key k isn't already in the map add it to the map, and
43      return false.  Otherwise return true.  */
44 
add(const Key & k)45   bool add (const Key &k)
46     {
47       Key *e = m_table.find_slot_with_hash (k, Traits::hash (k), INSERT);
48       bool existed = !Traits::is_empty (*e);
49       if (!existed)
50 	*e = k;
51 
52       return existed;
53     }
54 
55   /* if the passed in key is in the map return its value otherwise NULL.  */
56 
contains(const Key & k)57   bool contains (const Key &k)
58     {
59       Key &e = m_table.find_with_hash (k, Traits::hash (k));
60       return !Traits::is_empty (e);
61     }
62 
remove(const Key & k)63   void remove (const Key &k)
64     {
65       m_table.remove_elt_with_hash (k, Traits::hash (k));
66     }
67 
68   /* Call the call back on each pair of key and value with the passed in
69      arg.  */
70 
71   template<typename Arg, bool (*f)(const typename Traits::value_type &, Arg)>
traverse(Arg a)72   void traverse (Arg a) const
73     {
74       for (typename hash_table<Traits>::iterator iter = m_table.begin ();
75 	   iter != m_table.end (); ++iter)
76 	f (*iter, a);
77     }
78 
79   /* Return the number of elements in the set.  */
80 
elements()81   size_t elements () const { return m_table.elements (); }
82 
83   class iterator
84   {
85   public:
iterator(const typename hash_table<Traits>::iterator & iter)86     explicit iterator (const typename hash_table<Traits>::iterator &iter) :
87       m_iter (iter) {}
88 
89     iterator &operator++ ()
90       {
91 	++m_iter;
92 	return *this;
93       }
94 
95     Key
96     operator* ()
97       {
98 	return *m_iter;
99       }
100 
101     bool
102     operator != (const iterator &other) const
103       {
104 	return m_iter != other.m_iter;
105       }
106 
107   private:
108     typename hash_table<Traits>::iterator m_iter;
109   };
110 
111   /* Standard iterator retrieval methods.  */
112 
begin()113   iterator begin () const { return iterator (m_table.begin ()); }
end()114   iterator end () const { return iterator (m_table.end ()); }
115 
116 
117 private:
118 
119   template<typename T, typename U> friend void gt_ggc_mx (hash_set<T, U> *);
120   template<typename T, typename U> friend void gt_pch_nx (hash_set<T, U> *);
121       template<typename T, typename U> friend void gt_pch_nx (hash_set<T, U> *, gt_pointer_operator, void *);
122 
123   hash_table<Traits> m_table;
124 };
125 
126 /* ggc marking routines.  */
127 
128 template<typename K, typename H>
129 static inline void
gt_ggc_mx(hash_set<K,H> * h)130 gt_ggc_mx (hash_set<K, H> *h)
131 {
132   gt_ggc_mx (&h->m_table);
133 }
134 
135 template<typename K, typename H>
136 static inline void
gt_pch_nx(hash_set<K,H> * h)137 gt_pch_nx (hash_set<K, H> *h)
138 {
139   gt_pch_nx (&h->m_table);
140 }
141 
142 template<typename K, typename H>
143 static inline void
gt_pch_nx(hash_set<K,H> * h,gt_pointer_operator op,void * cookie)144 gt_pch_nx (hash_set<K, H> *h, gt_pointer_operator op, void *cookie)
145 {
146   op (&h->m_table.m_entries, cookie);
147 }
148 
149 #endif
150