1/* A type-safe hash map.
2 Copyright (C) 2014-2017 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify it under
7the terms of the GNU General Public License as published by the Free
8Software Foundation; either version 3, or (at your option) any later
9version.
10
11GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12WARRANTY; without even the implied warranty of MERCHANTABILITY or
13FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14for more details.
15
16You should have received a copy of the GNU General Public License
17along with GCC; see the file COPYING3. If not see
18<http://www.gnu.org/licenses/>. */
19
20
21#ifndef hash_map_h
22#define hash_map_h
23
24template<typename KeyId, typename Value,
25 typename Traits>
26class GTY((user)) hash_map
27{
28 typedef typename Traits::key_type Key;
29 struct hash_entry
30 {
31 Key m_key;
32 Value m_value;
33
34 typedef hash_entry value_type;
35 typedef Key compare_type;
36
37 static hashval_t hash (const hash_entry &e)
38 {
39 return Traits::hash (e.m_key);
40 }
41
42 static bool equal (const hash_entry &a, const Key &b)
43 {
44 return Traits::equal_keys (a.m_key, b);
45 }
46
47 static void remove (hash_entry &e) { Traits::remove (e); }
48
49 static void mark_deleted (hash_entry &e) { Traits::mark_deleted (e); }
50
51 static bool is_deleted (const hash_entry &e)
52 {
53 return Traits::is_deleted (e);
54 }
55
56 static void mark_empty (hash_entry &e) { Traits::mark_empty (e); }
57 static bool is_empty (const hash_entry &e) { return Traits::is_empty (e); }
58
59 static void ggc_mx (hash_entry &e)
60 {
61 gt_ggc_mx (e.m_key);
62 gt_ggc_mx (e.m_value);
63 }
64
65 static void ggc_maybe_mx (hash_entry &e)
66 {
67 if (Traits::maybe_mx)
68 ggc_mx (e);
69 }
70
71 static void pch_nx (hash_entry &e)
72 {
73 gt_pch_nx (e.m_key);
74 gt_pch_nx (e.m_value);
75 }
76
77 static void pch_nx (hash_entry &e, gt_pointer_operator op, void *c)
78 {
79 pch_nx_helper (e.m_key, op, c);
80 pch_nx_helper (e.m_value, op, c);
81 }
82
83 static int keep_cache_entry (hash_entry &e)
84 {
85 return ggc_marked_p (e.m_key);
86 }
87
88 private:
89 template<typename T>
90 static void
91 pch_nx_helper (T &x, gt_pointer_operator op, void *cookie)
92 {
93 gt_pch_nx (&x, op, cookie);
94 }
95
96 static void
97 pch_nx_helper (int, gt_pointer_operator, void *)
98 {
99 }
100
101 static void
102 pch_nx_helper (unsigned int, gt_pointer_operator, void *)
103 {
104 }
105
106 static void
107 pch_nx_helper (bool, gt_pointer_operator, void *)
108 {
109 }
110
111 template<typename T>
112 static void
113 pch_nx_helper (T *&x, gt_pointer_operator op, void *cookie)
114 {
115 op (&x, cookie);
116 }
117 };
118
119public:
120 explicit hash_map (size_t n = 13, bool ggc = false,
121 bool gather_mem_stats = GATHER_STATISTICS
122 CXX_MEM_STAT_INFO)
123 : m_table (n, ggc, gather_mem_stats, HASH_MAP_ORIGIN PASS_MEM_STAT) {}
124
125 explicit hash_map (const hash_map &h, bool ggc = false,
126 bool gather_mem_stats = GATHER_STATISTICS
127 CXX_MEM_STAT_INFO)
128 : m_table (h.m_table, ggc, gather_mem_stats,
129 HASH_MAP_ORIGIN PASS_MEM_STAT) {}
130
131 /* Create a hash_map in ggc memory. */
132 static hash_map *create_ggc (size_t size,
133 bool gather_mem_stats = GATHER_STATISTICS
134 CXX_MEM_STAT_INFO)
135 {
136 hash_map *map = ggc_alloc<hash_map> ();
137 new (map) hash_map (size, true, gather_mem_stats PASS_MEM_STAT);
138 return map;
139 }
140
141 /* If key k isn't already in the map add key k with value v to the map, and
142 return false. Otherwise set the value of the entry for key k to be v and
143 return true. */
144
145 bool put (const Key &k, const Value &v)
146 {
147 hash_entry *e = m_table.find_slot_with_hash (k, Traits::hash (k),
148 INSERT);
149 bool existed = !hash_entry::is_empty (*e);
150 if (!existed)
151 e->m_key = k;
152
153 e->m_value = v;
154 return existed;
155 }
156
157 /* if the passed in key is in the map return its value otherwise NULL. */
158
159 Value *get (const Key &k)
160 {
161 hash_entry &e = m_table.find_with_hash (k, Traits::hash (k));
162 return Traits::is_empty (e) ? NULL : &e.m_value;
163 }
164
165 /* Return a reference to the value for the passed in key, creating the entry
166 if it doesn't already exist. If existed is not NULL then it is set to false
167 if the key was not previously in the map, and true otherwise. */
168
169 Value &get_or_insert (const Key &k, bool *existed = NULL)
170 {
171 hash_entry *e = m_table.find_slot_with_hash (k, Traits::hash (k),
172 INSERT);
173 bool ins = Traits::is_empty (*e);
174 if (ins)
175 e->m_key = k;
176
177 if (existed != NULL)
178 *existed = !ins;
179
180 return e->m_value;
181 }
182
183 void remove (const Key &k)
184 {
185 m_table.remove_elt_with_hash (k, Traits::hash (k));
186 }
187
188 /* Call the call back on each pair of key and value with the passed in
189 arg. */
190
191 template<typename Arg, bool (*f)(const typename Traits::key_type &,
192 const Value &, Arg)>
193 void traverse (Arg a) const
194 {
195 for (typename hash_table<hash_entry>::iterator iter = m_table.begin ();
196 iter != m_table.end (); ++iter)
197 f ((*iter).m_key, (*iter).m_value, a);
198 }
199
200 template<typename Arg, bool (*f)(const typename Traits::key_type &,
201 Value *, Arg)>
202 void traverse (Arg a) const
203 {
204 for (typename hash_table<hash_entry>::iterator iter = m_table.begin ();
205 iter != m_table.end (); ++iter)
206 if (!f ((*iter).m_key, &(*iter).m_value, a))
207 break;
208 }
209
210 size_t elements () const { return m_table.elements (); }
211
212 void empty () { m_table.empty(); }
213
214 class iterator
215 {
216 public:
217 explicit iterator (const typename hash_table<hash_entry>::iterator &iter) :
218 m_iter (iter) {}
219
220 iterator &operator++ ()
221 {
222 ++m_iter;
223 return *this;
224 }
225
226 std::pair<Key, Value> operator* ()
227 {
228 hash_entry &e = *m_iter;
229 return std::pair<Key, Value> (e.m_key, e.m_value);
230 }
231
232 bool
233 operator != (const iterator &other) const
234 {
235 return m_iter != other.m_iter;
236 }
237
238 private:
239 typename hash_table<hash_entry>::iterator m_iter;
240 };
241
242 /* Standard iterator retrieval methods. */
243
244 iterator begin () const { return iterator (m_table.begin ()); }
245 iterator end () const { return iterator (m_table.end ()); }
246
247private:
248
249 template<typename T, typename U, typename V> friend void gt_ggc_mx (hash_map<T, U, V> *);
250 template<typename T, typename U, typename V> friend void gt_pch_nx (hash_map<T, U, V> *);
251 template<typename T, typename U, typename V> friend void gt_pch_nx (hash_map<T, U, V> *, gt_pointer_operator, void *);
252 template<typename T, typename U, typename V> friend void gt_cleare_cache (hash_map<T, U, V> *);
253
254 hash_table<hash_entry> m_table;
255};
256
257/* ggc marking routines. */
258
259template<typename K, typename V, typename H>
260static inline void
261gt_ggc_mx (hash_map<K, V, H> *h)
262{
263 gt_ggc_mx (&h->m_table);
264}
265
266template<typename K, typename V, typename H>
267static inline void
268gt_pch_nx (hash_map<K, V, H> *h)
269{
270 gt_pch_nx (&h->m_table);
271}
272
273template<typename K, typename V, typename H>
274static inline void
275gt_cleare_cache (hash_map<K, V, H> *h)
276{
277 if (h)
278 gt_cleare_cache (&h->m_table);
279}
280
281template<typename K, typename V, typename H>
282static inline void
283gt_pch_nx (hash_map<K, V, H> *h, gt_pointer_operator op, void *cookie)
284{
285 op (&h->m_table.m_entries, cookie);
286}
287
288#endif
289