1//===--- ImmutableMap.h - Immutable (functional) map interface --*- 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 ImmutableMap class.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_ADT_IMMUTABLEMAP_H
15#define LLVM_ADT_IMMUTABLEMAP_H
16
17#include "llvm/ADT/ImmutableSet.h"
18
19namespace llvm {
20
21/// ImutKeyValueInfo -Traits class used by ImmutableMap.  While both the first
22/// and second elements in a pair are used to generate profile information,
23/// only the first element (the key) is used by isEqual and isLess.
24template <typename T, typename S>
25struct ImutKeyValueInfo {
26  typedef const std::pair<T,S> value_type;
27  typedef const value_type& value_type_ref;
28  typedef const T   key_type;
29  typedef const T&  key_type_ref;
30  typedef const S   data_type;
31  typedef const S&  data_type_ref;
32
33  static inline key_type_ref KeyOfValue(value_type_ref V) {
34    return V.first;
35  }
36
37  static inline data_type_ref DataOfValue(value_type_ref V) {
38    return V.second;
39  }
40
41  static inline bool isEqual(key_type_ref L, key_type_ref R) {
42    return ImutContainerInfo<T>::isEqual(L,R);
43  }
44  static inline bool isLess(key_type_ref L, key_type_ref R) {
45    return ImutContainerInfo<T>::isLess(L,R);
46  }
47
48  static inline bool isDataEqual(data_type_ref L, data_type_ref R) {
49    return ImutContainerInfo<S>::isEqual(L,R);
50  }
51
52  static inline void Profile(FoldingSetNodeID& ID, value_type_ref V) {
53    ImutContainerInfo<T>::Profile(ID, V.first);
54    ImutContainerInfo<S>::Profile(ID, V.second);
55  }
56};
57
58
59template <typename KeyT, typename ValT,
60          typename ValInfo = ImutKeyValueInfo<KeyT,ValT> >
61class ImmutableMap {
62public:
63  typedef typename ValInfo::value_type      value_type;
64  typedef typename ValInfo::value_type_ref  value_type_ref;
65  typedef typename ValInfo::key_type        key_type;
66  typedef typename ValInfo::key_type_ref    key_type_ref;
67  typedef typename ValInfo::data_type       data_type;
68  typedef typename ValInfo::data_type_ref   data_type_ref;
69  typedef ImutAVLTree<ValInfo>              TreeTy;
70
71protected:
72  TreeTy* Root;
73
74public:
75  /// Constructs a map from a pointer to a tree root.  In general one
76  /// should use a Factory object to create maps instead of directly
77  /// invoking the constructor, but there are cases where make this
78  /// constructor public is useful.
79  explicit ImmutableMap(const TreeTy* R) : Root(const_cast<TreeTy*>(R)) {
80    if (Root) { Root->retain(); }
81  }
82  ImmutableMap(const ImmutableMap &X) : Root(X.Root) {
83    if (Root) { Root->retain(); }
84  }
85  ImmutableMap &operator=(const ImmutableMap &X) {
86    if (Root != X.Root) {
87      if (X.Root) { X.Root->retain(); }
88      if (Root) { Root->release(); }
89      Root = X.Root;
90    }
91    return *this;
92  }
93  ~ImmutableMap() {
94    if (Root) { Root->release(); }
95  }
96
97  class Factory {
98    typename TreeTy::Factory F;
99    const bool Canonicalize;
100
101  public:
102    Factory(bool canonicalize = true)
103      : Canonicalize(canonicalize) {}
104
105    Factory(BumpPtrAllocator& Alloc, bool canonicalize = true)
106      : F(Alloc), Canonicalize(canonicalize) {}
107
108    ImmutableMap getEmptyMap() { return ImmutableMap(F.getEmptyTree()); }
109
110    ImmutableMap add(ImmutableMap Old, key_type_ref K, data_type_ref D) {
111      TreeTy *T = F.add(Old.Root, std::pair<key_type,data_type>(K,D));
112      return ImmutableMap(Canonicalize ? F.getCanonicalTree(T): T);
113    }
114
115    ImmutableMap remove(ImmutableMap Old, key_type_ref K) {
116      TreeTy *T = F.remove(Old.Root,K);
117      return ImmutableMap(Canonicalize ? F.getCanonicalTree(T): T);
118    }
119
120    typename TreeTy::Factory *getTreeFactory() const {
121      return const_cast<typename TreeTy::Factory *>(&F);
122    }
123
124  private:
125    Factory(const Factory& RHS) LLVM_DELETED_FUNCTION;
126    void operator=(const Factory& RHS) LLVM_DELETED_FUNCTION;
127  };
128
129  bool contains(key_type_ref K) const {
130    return Root ? Root->contains(K) : false;
131  }
132
133  bool operator==(const ImmutableMap &RHS) const {
134    return Root && RHS.Root ? Root->isEqual(*RHS.Root) : Root == RHS.Root;
135  }
136
137  bool operator!=(const ImmutableMap &RHS) const {
138    return Root && RHS.Root ? Root->isNotEqual(*RHS.Root) : Root != RHS.Root;
139  }
140
141  TreeTy *getRoot() const {
142    if (Root) { Root->retain(); }
143    return Root;
144  }
145
146  TreeTy *getRootWithoutRetain() const {
147    return Root;
148  }
149
150  void manualRetain() {
151    if (Root) Root->retain();
152  }
153
154  void manualRelease() {
155    if (Root) Root->release();
156  }
157
158  bool isEmpty() const { return !Root; }
159
160  //===--------------------------------------------------===//
161  // Foreach - A limited form of map iteration.
162  //===--------------------------------------------------===//
163
164private:
165  template <typename Callback>
166  struct CBWrapper {
167    Callback C;
168    void operator()(value_type_ref V) { C(V.first,V.second); }
169  };
170
171  template <typename Callback>
172  struct CBWrapperRef {
173    Callback &C;
174    CBWrapperRef(Callback& c) : C(c) {}
175
176    void operator()(value_type_ref V) { C(V.first,V.second); }
177  };
178
179public:
180  template <typename Callback>
181  void foreach(Callback& C) {
182    if (Root) {
183      CBWrapperRef<Callback> CB(C);
184      Root->foreach(CB);
185    }
186  }
187
188  template <typename Callback>
189  void foreach() {
190    if (Root) {
191      CBWrapper<Callback> CB;
192      Root->foreach(CB);
193    }
194  }
195
196  //===--------------------------------------------------===//
197  // For testing.
198  //===--------------------------------------------------===//
199
200  void verify() const { if (Root) Root->verify(); }
201
202  //===--------------------------------------------------===//
203  // Iterators.
204  //===--------------------------------------------------===//
205
206  class iterator {
207    typename TreeTy::iterator itr;
208
209    iterator() {}
210    iterator(TreeTy* t) : itr(t) {}
211    friend class ImmutableMap;
212
213  public:
214    typedef ptrdiff_t difference_type;
215    typedef typename ImmutableMap<KeyT,ValT,ValInfo>::value_type value_type;
216    typedef typename ImmutableMap<KeyT,ValT,ValInfo>::value_type_ref reference;
217    typedef typename iterator::value_type *pointer;
218    typedef std::bidirectional_iterator_tag iterator_category;
219
220    typename iterator::reference operator*() const { return itr->getValue(); }
221    typename iterator::pointer   operator->() const { return &itr->getValue(); }
222
223    key_type_ref getKey() const { return itr->getValue().first; }
224    data_type_ref getData() const { return itr->getValue().second; }
225
226    iterator& operator++() { ++itr; return *this; }
227    iterator  operator++(int) { iterator tmp(*this); ++itr; return tmp; }
228    iterator& operator--() { --itr; return *this; }
229    iterator  operator--(int) { iterator tmp(*this); --itr; return tmp; }
230
231    bool operator==(const iterator& RHS) const { return RHS.itr == itr; }
232    bool operator!=(const iterator& RHS) const { return RHS.itr != itr; }
233  };
234
235  iterator begin() const { return iterator(Root); }
236  iterator end() const { return iterator(); }
237
238  data_type* lookup(key_type_ref K) const {
239    if (Root) {
240      TreeTy* T = Root->find(K);
241      if (T) return &T->getValue().second;
242    }
243
244    return nullptr;
245  }
246
247  /// getMaxElement - Returns the <key,value> pair in the ImmutableMap for
248  ///  which key is the highest in the ordering of keys in the map.  This
249  ///  method returns NULL if the map is empty.
250  value_type* getMaxElement() const {
251    return Root ? &(Root->getMaxElement()->getValue()) : nullptr;
252  }
253
254  //===--------------------------------------------------===//
255  // Utility methods.
256  //===--------------------------------------------------===//
257
258  unsigned getHeight() const { return Root ? Root->getHeight() : 0; }
259
260  static inline void Profile(FoldingSetNodeID& ID, const ImmutableMap& M) {
261    ID.AddPointer(M.Root);
262  }
263
264  inline void Profile(FoldingSetNodeID& ID) const {
265    return Profile(ID,*this);
266  }
267};
268
269// NOTE: This will possibly become the new implementation of ImmutableMap some day.
270template <typename KeyT, typename ValT,
271typename ValInfo = ImutKeyValueInfo<KeyT,ValT> >
272class ImmutableMapRef {
273public:
274  typedef typename ValInfo::value_type      value_type;
275  typedef typename ValInfo::value_type_ref  value_type_ref;
276  typedef typename ValInfo::key_type        key_type;
277  typedef typename ValInfo::key_type_ref    key_type_ref;
278  typedef typename ValInfo::data_type       data_type;
279  typedef typename ValInfo::data_type_ref   data_type_ref;
280  typedef ImutAVLTree<ValInfo>              TreeTy;
281  typedef typename TreeTy::Factory          FactoryTy;
282
283protected:
284  TreeTy *Root;
285  FactoryTy *Factory;
286
287public:
288  /// Constructs a map from a pointer to a tree root.  In general one
289  /// should use a Factory object to create maps instead of directly
290  /// invoking the constructor, but there are cases where make this
291  /// constructor public is useful.
292  explicit ImmutableMapRef(const TreeTy* R, FactoryTy *F)
293    : Root(const_cast<TreeTy*>(R)),
294      Factory(F) {
295    if (Root) { Root->retain(); }
296  }
297
298  explicit ImmutableMapRef(const ImmutableMap<KeyT, ValT> &X,
299                           typename ImmutableMap<KeyT, ValT>::Factory &F)
300    : Root(X.getRootWithoutRetain()),
301      Factory(F.getTreeFactory()) {
302    if (Root) { Root->retain(); }
303  }
304
305  ImmutableMapRef(const ImmutableMapRef &X)
306    : Root(X.Root),
307      Factory(X.Factory) {
308    if (Root) { Root->retain(); }
309  }
310
311  ImmutableMapRef &operator=(const ImmutableMapRef &X) {
312    if (Root != X.Root) {
313      if (X.Root)
314        X.Root->retain();
315
316      if (Root)
317        Root->release();
318
319      Root = X.Root;
320      Factory = X.Factory;
321    }
322    return *this;
323  }
324
325  ~ImmutableMapRef() {
326    if (Root)
327      Root->release();
328  }
329
330  static inline ImmutableMapRef getEmptyMap(FactoryTy *F) {
331    return ImmutableMapRef(0, F);
332  }
333
334  void manualRetain() {
335    if (Root) Root->retain();
336  }
337
338  void manualRelease() {
339    if (Root) Root->release();
340  }
341
342  ImmutableMapRef add(key_type_ref K, data_type_ref D) const {
343    TreeTy *NewT = Factory->add(Root, std::pair<key_type, data_type>(K, D));
344    return ImmutableMapRef(NewT, Factory);
345  }
346
347  ImmutableMapRef remove(key_type_ref K) const {
348    TreeTy *NewT = Factory->remove(Root, K);
349    return ImmutableMapRef(NewT, Factory);
350  }
351
352  bool contains(key_type_ref K) const {
353    return Root ? Root->contains(K) : false;
354  }
355
356  ImmutableMap<KeyT, ValT> asImmutableMap() const {
357    return ImmutableMap<KeyT, ValT>(Factory->getCanonicalTree(Root));
358  }
359
360  bool operator==(const ImmutableMapRef &RHS) const {
361    return Root && RHS.Root ? Root->isEqual(*RHS.Root) : Root == RHS.Root;
362  }
363
364  bool operator!=(const ImmutableMapRef &RHS) const {
365    return Root && RHS.Root ? Root->isNotEqual(*RHS.Root) : Root != RHS.Root;
366  }
367
368  bool isEmpty() const { return !Root; }
369
370  //===--------------------------------------------------===//
371  // For testing.
372  //===--------------------------------------------------===//
373
374  void verify() const { if (Root) Root->verify(); }
375
376  //===--------------------------------------------------===//
377  // Iterators.
378  //===--------------------------------------------------===//
379
380  class iterator {
381    typename TreeTy::iterator itr;
382
383    iterator() {}
384    iterator(TreeTy* t) : itr(t) {}
385    friend class ImmutableMapRef;
386
387  public:
388    value_type_ref operator*() const { return itr->getValue(); }
389    value_type*    operator->() const { return &itr->getValue(); }
390
391    key_type_ref getKey() const { return itr->getValue().first; }
392    data_type_ref getData() const { return itr->getValue().second; }
393
394
395    iterator& operator++() { ++itr; return *this; }
396    iterator  operator++(int) { iterator tmp(*this); ++itr; return tmp; }
397    iterator& operator--() { --itr; return *this; }
398    iterator  operator--(int) { iterator tmp(*this); --itr; return tmp; }
399    bool operator==(const iterator& RHS) const { return RHS.itr == itr; }
400    bool operator!=(const iterator& RHS) const { return RHS.itr != itr; }
401  };
402
403  iterator begin() const { return iterator(Root); }
404  iterator end() const { return iterator(); }
405
406  data_type* lookup(key_type_ref K) const {
407    if (Root) {
408      TreeTy* T = Root->find(K);
409      if (T) return &T->getValue().second;
410    }
411
412    return 0;
413  }
414
415  /// getMaxElement - Returns the <key,value> pair in the ImmutableMap for
416  ///  which key is the highest in the ordering of keys in the map.  This
417  ///  method returns NULL if the map is empty.
418  value_type* getMaxElement() const {
419    return Root ? &(Root->getMaxElement()->getValue()) : 0;
420  }
421
422  //===--------------------------------------------------===//
423  // Utility methods.
424  //===--------------------------------------------------===//
425
426  unsigned getHeight() const { return Root ? Root->getHeight() : 0; }
427
428  static inline void Profile(FoldingSetNodeID& ID, const ImmutableMapRef &M) {
429    ID.AddPointer(M.Root);
430  }
431
432  inline void Profile(FoldingSetNodeID& ID) const {
433    return Profile(ID, *this);
434  }
435};
436
437} // end namespace llvm
438
439#endif
440