1//===--- ImmutableMap.h - Immutable (functional) map interface --*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8///
9/// \file
10/// This file defines the ImmutableMap class.
11///
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_ADT_IMMUTABLEMAP_H
15#define LLVM_ADT_IMMUTABLEMAP_H
16
17#include "llvm/ADT/FoldingSet.h"
18#include "llvm/ADT/ImmutableSet.h"
19#include "llvm/Support/Allocator.h"
20#include <utility>
21
22namespace llvm {
23
24/// ImutKeyValueInfo -Traits class used by ImmutableMap. While both the first
25/// and second elements in a pair are used to generate profile information,
26/// only the first element (the key) is used by isEqual and isLess.
27template <typename T, typename S>
28struct ImutKeyValueInfo {
29 using value_type = const std::pair<T,S>;
30 using value_type_ref = const value_type&;
31 using key_type = const T;
32 using key_type_ref = const T&;
33 using data_type = const S;
34 using data_type_ref = const S&;
35
36 static inline key_type_ref KeyOfValue(value_type_ref V) {
37 return V.first;
38 }
39
40 static inline data_type_ref DataOfValue(value_type_ref V) {
41 return V.second;
42 }
43
44 static inline bool isEqual(key_type_ref L, key_type_ref R) {
45 return ImutContainerInfo<T>::isEqual(L,R);
46 }
47 static inline bool isLess(key_type_ref L, key_type_ref R) {
48 return ImutContainerInfo<T>::isLess(L,R);
49 }
50
51 static inline bool isDataEqual(data_type_ref L, data_type_ref R) {
52 return ImutContainerInfo<S>::isEqual(L,R);
53 }
54
55 static inline void Profile(FoldingSetNodeID& ID, value_type_ref V) {
56 ImutContainerInfo<T>::Profile(ID, V.first);
57 ImutContainerInfo<S>::Profile(ID, V.second);
58 }
59};
60
61template <typename KeyT, typename ValT,
62 typename ValInfo = ImutKeyValueInfo<KeyT,ValT>>
63class ImmutableMap {
64public:
65 using value_type = typename ValInfo::value_type;
66 using value_type_ref = typename ValInfo::value_type_ref;
67 using key_type = typename ValInfo::key_type;
68 using key_type_ref = typename ValInfo::key_type_ref;
69 using data_type = typename ValInfo::data_type;
70 using data_type_ref = typename ValInfo::data_type_ref;
71 using TreeTy = ImutAVLTree<ValInfo>;
72
73protected:
74 IntrusiveRefCntPtr<TreeTy> Root;
75
76public:
77 /// Constructs a map from a pointer to a tree root. In general one
78 /// should use a Factory object to create maps instead of directly
79 /// invoking the constructor, but there are cases where make this
80 /// constructor public is useful.
81 explicit ImmutableMap(const TreeTy *R) : Root(const_cast<TreeTy *>(R)) {}
82
83 class Factory {
84 typename TreeTy::Factory F;
85 const bool Canonicalize;
86
87 public:
88 Factory(bool canonicalize = true) : Canonicalize(canonicalize) {}
89
90 Factory(BumpPtrAllocator &Alloc, bool canonicalize = true)
91 : F(Alloc), Canonicalize(canonicalize) {}
92
93 Factory(const Factory &) = delete;
94 Factory &operator=(const Factory &) = delete;
95
96 ImmutableMap getEmptyMap() { return ImmutableMap(F.getEmptyTree()); }
97
98 [[nodiscard]] ImmutableMap add(ImmutableMap Old, key_type_ref K,
99 data_type_ref D) {
100 TreeTy *T = F.add(Old.Root.get(), std::pair<key_type, data_type>(K, D));
101 return ImmutableMap(Canonicalize ? F.getCanonicalTree(T): T);
102 }
103
104 [[nodiscard]] ImmutableMap remove(ImmutableMap Old, key_type_ref K) {
105 TreeTy *T = F.remove(Old.Root.get(), K);
106 return ImmutableMap(Canonicalize ? F.getCanonicalTree(T): T);
107 }
108
109 typename TreeTy::Factory *getTreeFactory() const {
110 return const_cast<typename TreeTy::Factory *>(&F);
111 }
112 };
113
114 bool contains(key_type_ref K) const {
115 return Root ? Root->contains(K) : false;
116 }
117
118 bool operator==(const ImmutableMap &RHS) const {
119 return Root && RHS.Root ? Root->isEqual(*RHS.Root.get()) : Root == RHS.Root;
120 }
121
122 bool operator!=(const ImmutableMap &RHS) const {
123 return Root && RHS.Root ? Root->isNotEqual(*RHS.Root.get())
124 : Root != RHS.Root;
125 }
126
127 TreeTy *getRoot() const {
128 if (Root) { Root->retain(); }
129 return Root.get();
130 }
131
132 TreeTy *getRootWithoutRetain() const { return Root.get(); }
133
134 void manualRetain() {
135 if (Root) Root->retain();
136 }
137
138 void manualRelease() {
139 if (Root) Root->release();
140 }
141
142 bool isEmpty() const { return !Root; }
143
144public:
145 //===--------------------------------------------------===//
146 // For testing.
147 //===--------------------------------------------------===//
148
149 void verify() const { if (Root) Root->verify(); }
150
151 //===--------------------------------------------------===//
152 // Iterators.
153 //===--------------------------------------------------===//
154
155 class iterator : public ImutAVLValueIterator<ImmutableMap> {
156 friend class ImmutableMap;
157
158 iterator() = default;
159 explicit iterator(TreeTy *Tree) : iterator::ImutAVLValueIterator(Tree) {}
160
161 public:
162 key_type_ref getKey() const { return (*this)->first; }
163 data_type_ref getData() const { return (*this)->second; }
164 };
165
166 iterator begin() const { return iterator(Root.get()); }
167 iterator end() const { return iterator(); }
168
169 data_type* lookup(key_type_ref K) const {
170 if (Root) {
171 TreeTy* T = Root->find(K);
172 if (T) return &T->getValue().second;
173 }
174
175 return nullptr;
176 }
177
178 /// getMaxElement - Returns the <key,value> pair in the ImmutableMap for
179 /// which key is the highest in the ordering of keys in the map. This
180 /// method returns NULL if the map is empty.
181 value_type* getMaxElement() const {
182 return Root ? &(Root->getMaxElement()->getValue()) : nullptr;
183 }
184
185 //===--------------------------------------------------===//
186 // Utility methods.
187 //===--------------------------------------------------===//
188
189 unsigned getHeight() const { return Root ? Root->getHeight() : 0; }
190
191 static inline void Profile(FoldingSetNodeID& ID, const ImmutableMap& M) {
192 ID.AddPointer(Ptr: M.Root.get());
193 }
194
195 inline void Profile(FoldingSetNodeID& ID) const {
196 return Profile(ID,*this);
197 }
198};
199
200// NOTE: This will possibly become the new implementation of ImmutableMap some day.
201template <typename KeyT, typename ValT,
202typename ValInfo = ImutKeyValueInfo<KeyT,ValT>>
203class ImmutableMapRef {
204public:
205 using value_type = typename ValInfo::value_type;
206 using value_type_ref = typename ValInfo::value_type_ref;
207 using key_type = typename ValInfo::key_type;
208 using key_type_ref = typename ValInfo::key_type_ref;
209 using data_type = typename ValInfo::data_type;
210 using data_type_ref = typename ValInfo::data_type_ref;
211 using TreeTy = ImutAVLTree<ValInfo>;
212 using FactoryTy = typename TreeTy::Factory;
213
214protected:
215 IntrusiveRefCntPtr<TreeTy> Root;
216 FactoryTy *Factory;
217
218public:
219 /// Constructs a map from a pointer to a tree root. In general one
220 /// should use a Factory object to create maps instead of directly
221 /// invoking the constructor, but there are cases where make this
222 /// constructor public is useful.
223 ImmutableMapRef(const TreeTy *R, FactoryTy *F)
224 : Root(const_cast<TreeTy *>(R)), Factory(F) {}
225
226 ImmutableMapRef(const ImmutableMap<KeyT, ValT> &X,
227 typename ImmutableMap<KeyT, ValT>::Factory &F)
228 : Root(X.getRootWithoutRetain()), Factory(F.getTreeFactory()) {}
229
230 static inline ImmutableMapRef getEmptyMap(FactoryTy *F) {
231 return ImmutableMapRef(nullptr, F);
232 }
233
234 void manualRetain() {
235 if (Root) Root->retain();
236 }
237
238 void manualRelease() {
239 if (Root) Root->release();
240 }
241
242 ImmutableMapRef add(key_type_ref K, data_type_ref D) const {
243 TreeTy *NewT =
244 Factory->add(Root.get(), std::pair<key_type, data_type>(K, D));
245 return ImmutableMapRef(NewT, Factory);
246 }
247
248 ImmutableMapRef remove(key_type_ref K) const {
249 TreeTy *NewT = Factory->remove(Root.get(), K);
250 return ImmutableMapRef(NewT, Factory);
251 }
252
253 bool contains(key_type_ref K) const {
254 return Root ? Root->contains(K) : false;
255 }
256
257 ImmutableMap<KeyT, ValT> asImmutableMap() const {
258 return ImmutableMap<KeyT, ValT>(Factory->getCanonicalTree(Root.get()));
259 }
260
261 bool operator==(const ImmutableMapRef &RHS) const {
262 return Root && RHS.Root ? Root->isEqual(*RHS.Root.get()) : Root == RHS.Root;
263 }
264
265 bool operator!=(const ImmutableMapRef &RHS) const {
266 return Root && RHS.Root ? Root->isNotEqual(*RHS.Root.get())
267 : Root != RHS.Root;
268 }
269
270 bool isEmpty() const { return !Root; }
271
272 //===--------------------------------------------------===//
273 // For testing.
274 //===--------------------------------------------------===//
275
276 void verify() const {
277 if (Root)
278 Root->verify();
279 }
280
281 //===--------------------------------------------------===//
282 // Iterators.
283 //===--------------------------------------------------===//
284
285 class iterator : public ImutAVLValueIterator<ImmutableMapRef> {
286 friend class ImmutableMapRef;
287
288 iterator() = default;
289 explicit iterator(TreeTy *Tree) : iterator::ImutAVLValueIterator(Tree) {}
290
291 public:
292 key_type_ref getKey() const { return (*this)->first; }
293 data_type_ref getData() const { return (*this)->second; }
294 };
295
296 iterator begin() const { return iterator(Root.get()); }
297 iterator end() const { return iterator(); }
298
299 data_type *lookup(key_type_ref K) const {
300 if (Root) {
301 TreeTy* T = Root->find(K);
302 if (T) return &T->getValue().second;
303 }
304
305 return nullptr;
306 }
307
308 /// getMaxElement - Returns the <key,value> pair in the ImmutableMap for
309 /// which key is the highest in the ordering of keys in the map. This
310 /// method returns NULL if the map is empty.
311 value_type* getMaxElement() const {
312 return Root ? &(Root->getMaxElement()->getValue()) : nullptr;
313 }
314
315 //===--------------------------------------------------===//
316 // Utility methods.
317 //===--------------------------------------------------===//
318
319 unsigned getHeight() const { return Root ? Root->getHeight() : 0; }
320
321 static inline void Profile(FoldingSetNodeID &ID, const ImmutableMapRef &M) {
322 ID.AddPointer(Ptr: M.Root.get());
323 }
324
325 inline void Profile(FoldingSetNodeID &ID) const { return Profile(ID, *this); }
326};
327
328} // end namespace llvm
329
330#endif // LLVM_ADT_IMMUTABLEMAP_H
331

source code of llvm/include/llvm/ADT/ImmutableMap.h