LLVM  10.0.0svn
ValueMap.h
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1 //===- ValueMap.h - Safe map from Values to data ----------------*- 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 // This file defines the ValueMap class. ValueMap maps Value* or any subclass
10 // to an arbitrary other type. It provides the DenseMap interface but updates
11 // itself to remain safe when keys are RAUWed or deleted. By default, when a
12 // key is RAUWed from V1 to V2, the old mapping V1->target is removed, and a new
13 // mapping V2->target is added. If V2 already existed, its old target is
14 // overwritten. When a key is deleted, its mapping is removed.
15 //
16 // You can override a ValueMap's Config parameter to control exactly what
17 // happens on RAUW and destruction and to get called back on each event. It's
18 // legal to call back into the ValueMap from a Config's callbacks. Config
19 // parameters should inherit from ValueMapConfig<KeyT> to get default
20 // implementations of all the methods ValueMap uses. See ValueMapConfig for
21 // documentation of the functions you can override.
22 //
23 //===----------------------------------------------------------------------===//
24 
25 #ifndef LLVM_IR_VALUEMAP_H
26 #define LLVM_IR_VALUEMAP_H
27 
28 #include "llvm/ADT/DenseMap.h"
29 #include "llvm/ADT/DenseMapInfo.h"
30 #include "llvm/ADT/None.h"
31 #include "llvm/ADT/Optional.h"
32 #include "llvm/IR/TrackingMDRef.h"
33 #include "llvm/IR/ValueHandle.h"
34 #include "llvm/Support/Casting.h"
35 #include "llvm/Support/Mutex.h"
36 #include <algorithm>
37 #include <cassert>
38 #include <cstddef>
39 #include <iterator>
40 #include <mutex>
41 #include <type_traits>
42 #include <utility>
43 
44 namespace llvm {
45 
46 template<typename KeyT, typename ValueT, typename Config>
48 template<typename DenseMapT, typename KeyT>
50 template<typename DenseMapT, typename KeyT>
52 
53 /// This class defines the default behavior for configurable aspects of
54 /// ValueMap<>. User Configs should inherit from this class to be as compatible
55 /// as possible with future versions of ValueMap.
56 template<typename KeyT, typename MutexT = sys::Mutex>
58  using mutex_type = MutexT;
59 
60  /// If FollowRAUW is true, the ValueMap will update mappings on RAUW. If it's
61  /// false, the ValueMap will leave the original mapping in place.
62  enum { FollowRAUW = true };
63 
64  // All methods will be called with a first argument of type ExtraData. The
65  // default implementations in this class take a templated first argument so
66  // that users' subclasses can use any type they want without having to
67  // override all the defaults.
68  struct ExtraData {};
69 
70  template<typename ExtraDataT>
71  static void onRAUW(const ExtraDataT & /*Data*/, KeyT /*Old*/, KeyT /*New*/) {}
72  template<typename ExtraDataT>
73  static void onDelete(const ExtraDataT &/*Data*/, KeyT /*Old*/) {}
74 
75  /// Returns a mutex that should be acquired around any changes to the map.
76  /// This is only acquired from the CallbackVH (and held around calls to onRAUW
77  /// and onDelete) and not inside other ValueMap methods. NULL means that no
78  /// mutex is necessary.
79  template<typename ExtraDataT>
80  static mutex_type *getMutex(const ExtraDataT &/*Data*/) { return nullptr; }
81 };
82 
83 /// See the file comment.
84 template<typename KeyT, typename ValueT, typename Config =ValueMapConfig<KeyT>>
85 class ValueMap {
86  friend class ValueMapCallbackVH<KeyT, ValueT, Config>;
87 
91  using ExtraData = typename Config::ExtraData;
92 
93  MapT Map;
94  Optional<MDMapT> MDMap;
95  ExtraData Data;
96 
97 public:
98  using key_type = KeyT;
100  using value_type = std::pair<KeyT, ValueT>;
102 
103  explicit ValueMap(unsigned NumInitBuckets = 64)
104  : Map(NumInitBuckets), Data() {}
105  explicit ValueMap(const ExtraData &Data, unsigned NumInitBuckets = 64)
106  : Map(NumInitBuckets), Data(Data) {}
107  // ValueMap can't be copied nor moved, beucase the callbacks store pointer
108  // to it.
109  ValueMap(const ValueMap &) = delete;
110  ValueMap(ValueMap &&) = delete;
111  ValueMap &operator=(const ValueMap &) = delete;
112  ValueMap &operator=(ValueMap &&) = delete;
113 
114  bool hasMD() const { return bool(MDMap); }
115  MDMapT &MD() {
116  if (!MDMap)
117  MDMap.emplace();
118  return *MDMap;
119  }
120  Optional<MDMapT> &getMDMap() { return MDMap; }
121 
122  /// Get the mapped metadata, if it's in the map.
124  if (!MDMap)
125  return None;
126  auto Where = MDMap->find(MD);
127  if (Where == MDMap->end())
128  return None;
129  return Where->second.get();
130  }
131 
134 
135  inline iterator begin() { return iterator(Map.begin()); }
136  inline iterator end() { return iterator(Map.end()); }
137  inline const_iterator begin() const { return const_iterator(Map.begin()); }
138  inline const_iterator end() const { return const_iterator(Map.end()); }
139 
140  bool empty() const { return Map.empty(); }
141  size_type size() const { return Map.size(); }
142 
143  /// Grow the map so that it has at least Size buckets. Does not shrink
144  void resize(size_t Size) { Map.resize(Size); }
145 
146  void clear() {
147  Map.clear();
148  MDMap.reset();
149  }
150 
151  /// Return 1 if the specified key is in the map, 0 otherwise.
152  size_type count(const KeyT &Val) const {
153  return Map.find_as(Val) == Map.end() ? 0 : 1;
154  }
155 
156  iterator find(const KeyT &Val) {
157  return iterator(Map.find_as(Val));
158  }
159  const_iterator find(const KeyT &Val) const {
160  return const_iterator(Map.find_as(Val));
161  }
162 
163  /// lookup - Return the entry for the specified key, or a default
164  /// constructed value if no such entry exists.
165  ValueT lookup(const KeyT &Val) const {
166  typename MapT::const_iterator I = Map.find_as(Val);
167  return I != Map.end() ? I->second : ValueT();
168  }
169 
170  // Inserts key,value pair into the map if the key isn't already in the map.
171  // If the key is already in the map, it returns false and doesn't update the
172  // value.
173  std::pair<iterator, bool> insert(const std::pair<KeyT, ValueT> &KV) {
174  auto MapResult = Map.insert(std::make_pair(Wrap(KV.first), KV.second));
175  return std::make_pair(iterator(MapResult.first), MapResult.second);
176  }
177 
178  std::pair<iterator, bool> insert(std::pair<KeyT, ValueT> &&KV) {
179  auto MapResult =
180  Map.insert(std::make_pair(Wrap(KV.first), std::move(KV.second)));
181  return std::make_pair(iterator(MapResult.first), MapResult.second);
182  }
183 
184  /// insert - Range insertion of pairs.
185  template<typename InputIt>
186  void insert(InputIt I, InputIt E) {
187  for (; I != E; ++I)
188  insert(*I);
189  }
190 
191  bool erase(const KeyT &Val) {
192  typename MapT::iterator I = Map.find_as(Val);
193  if (I == Map.end())
194  return false;
195 
196  Map.erase(I);
197  return true;
198  }
199  void erase(iterator I) {
200  return Map.erase(I.base());
201  }
202 
204  return Map.FindAndConstruct(Wrap(Key));
205  }
206 
207  ValueT &operator[](const KeyT &Key) {
208  return Map[Wrap(Key)];
209  }
210 
211  /// isPointerIntoBucketsArray - Return true if the specified pointer points
212  /// somewhere into the ValueMap's array of buckets (i.e. either to a key or
213  /// value in the ValueMap).
214  bool isPointerIntoBucketsArray(const void *Ptr) const {
215  return Map.isPointerIntoBucketsArray(Ptr);
216  }
217 
218  /// getPointerIntoBucketsArray() - Return an opaque pointer into the buckets
219  /// array. In conjunction with the previous method, this can be used to
220  /// determine whether an insertion caused the ValueMap to reallocate.
221  const void *getPointerIntoBucketsArray() const {
222  return Map.getPointerIntoBucketsArray();
223  }
224 
225 private:
226  // Takes a key being looked up in the map and wraps it into a
227  // ValueMapCallbackVH, the actual key type of the map. We use a helper
228  // function because ValueMapCVH is constructed with a second parameter.
229  ValueMapCVH Wrap(KeyT key) const {
230  // The only way the resulting CallbackVH could try to modify *this (making
231  // the const_cast incorrect) is if it gets inserted into the map. But then
232  // this function must have been called from a non-const method, making the
233  // const_cast ok.
234  return ValueMapCVH(key, const_cast<ValueMap*>(this));
235  }
236 };
237 
238 // This CallbackVH updates its ValueMap when the contained Value changes,
239 // according to the user's preferences expressed through the Config object.
240 template <typename KeyT, typename ValueT, typename Config>
241 class ValueMapCallbackVH final : public CallbackVH {
242  friend class ValueMap<KeyT, ValueT, Config>;
244 
246  using KeySansPointerT = typename std::remove_pointer<KeyT>::type;
247 
248  ValueMapT *Map;
249 
250  ValueMapCallbackVH(KeyT Key, ValueMapT *Map)
251  : CallbackVH(const_cast<Value*>(static_cast<const Value*>(Key))),
252  Map(Map) {}
253 
254  // Private constructor used to create empty/tombstone DenseMap keys.
255  ValueMapCallbackVH(Value *V) : CallbackVH(V), Map(nullptr) {}
256 
257 public:
258  KeyT Unwrap() const { return cast_or_null<KeySansPointerT>(getValPtr()); }
259 
260  void deleted() override {
261  // Make a copy that won't get changed even when *this is destroyed.
262  ValueMapCallbackVH Copy(*this);
263  typename Config::mutex_type *M = Config::getMutex(Copy.Map->Data);
264  std::unique_lock<typename Config::mutex_type> Guard;
265  if (M)
266  Guard = std::unique_lock<typename Config::mutex_type>(*M);
267  Config::onDelete(Copy.Map->Data, Copy.Unwrap()); // May destroy *this.
268  Copy.Map->Map.erase(Copy); // Definitely destroys *this.
269  }
270 
271  void allUsesReplacedWith(Value *new_key) override {
272  assert(isa<KeySansPointerT>(new_key) &&
273  "Invalid RAUW on key of ValueMap<>");
274  // Make a copy that won't get changed even when *this is destroyed.
275  ValueMapCallbackVH Copy(*this);
276  typename Config::mutex_type *M = Config::getMutex(Copy.Map->Data);
277  std::unique_lock<typename Config::mutex_type> Guard;
278  if (M)
279  Guard = std::unique_lock<typename Config::mutex_type>(*M);
280 
281  KeyT typed_new_key = cast<KeySansPointerT>(new_key);
282  // Can destroy *this:
283  Config::onRAUW(Copy.Map->Data, Copy.Unwrap(), typed_new_key);
284  if (Config::FollowRAUW) {
285  typename ValueMapT::MapT::iterator I = Copy.Map->Map.find(Copy);
286  // I could == Copy.Map->Map.end() if the onRAUW callback already
287  // removed the old mapping.
288  if (I != Copy.Map->Map.end()) {
289  ValueT Target(std::move(I->second));
290  Copy.Map->Map.erase(I); // Definitely destroys *this.
291  Copy.Map->insert(std::make_pair(typed_new_key, std::move(Target)));
292  }
293  }
294  }
295 };
296 
297 template<typename KeyT, typename ValueT, typename Config>
298 struct DenseMapInfo<ValueMapCallbackVH<KeyT, ValueT, Config>> {
300 
301  static inline VH getEmptyKey() {
303  }
304 
305  static inline VH getTombstoneKey() {
307  }
308 
309  static unsigned getHashValue(const VH &Val) {
311  }
312 
313  static unsigned getHashValue(const KeyT &Val) {
315  }
316 
317  static bool isEqual(const VH &LHS, const VH &RHS) {
318  return LHS == RHS;
319  }
320 
321  static bool isEqual(const KeyT &LHS, const VH &RHS) {
322  return LHS == RHS.getValPtr();
323  }
324 };
325 
326 template<typename DenseMapT, typename KeyT>
327 class ValueMapIterator :
328  public std::iterator<std::forward_iterator_tag,
329  std::pair<KeyT, typename DenseMapT::mapped_type>,
330  ptrdiff_t> {
331  using BaseT = typename DenseMapT::iterator;
332  using ValueT = typename DenseMapT::mapped_type;
333 
334  BaseT I;
335 
336 public:
337  ValueMapIterator() : I() {}
338  ValueMapIterator(BaseT I) : I(I) {}
339 
340  BaseT base() const { return I; }
341 
342  struct ValueTypeProxy {
343  const KeyT first;
344  ValueT& second;
345 
346  ValueTypeProxy *operator->() { return this; }
347 
348  operator std::pair<KeyT, ValueT>() const {
349  return std::make_pair(first, second);
350  }
351  };
352 
354  ValueTypeProxy Result = {I->first.Unwrap(), I->second};
355  return Result;
356  }
357 
359  return operator*();
360  }
361 
362  bool operator==(const ValueMapIterator &RHS) const {
363  return I == RHS.I;
364  }
365  bool operator!=(const ValueMapIterator &RHS) const {
366  return I != RHS.I;
367  }
368 
369  inline ValueMapIterator& operator++() { // Preincrement
370  ++I;
371  return *this;
372  }
373  ValueMapIterator operator++(int) { // Postincrement
374  ValueMapIterator tmp = *this; ++*this; return tmp;
375  }
376 };
377 
378 template<typename DenseMapT, typename KeyT>
379 class ValueMapConstIterator :
380  public std::iterator<std::forward_iterator_tag,
381  std::pair<KeyT, typename DenseMapT::mapped_type>,
382  ptrdiff_t> {
383  using BaseT = typename DenseMapT::const_iterator;
384  using ValueT = typename DenseMapT::mapped_type;
385 
386  BaseT I;
387 
388 public:
390  ValueMapConstIterator(BaseT I) : I(I) {}
392  : I(Other.base()) {}
393 
394  BaseT base() const { return I; }
395 
396  struct ValueTypeProxy {
397  const KeyT first;
398  const ValueT& second;
399  ValueTypeProxy *operator->() { return this; }
400  operator std::pair<KeyT, ValueT>() const {
401  return std::make_pair(first, second);
402  }
403  };
404 
406  ValueTypeProxy Result = {I->first.Unwrap(), I->second};
407  return Result;
408  }
409 
411  return operator*();
412  }
413 
414  bool operator==(const ValueMapConstIterator &RHS) const {
415  return I == RHS.I;
416  }
417  bool operator!=(const ValueMapConstIterator &RHS) const {
418  return I != RHS.I;
419  }
420 
421  inline ValueMapConstIterator& operator++() { // Preincrement
422  ++I;
423  return *this;
424  }
425  ValueMapConstIterator operator++(int) { // Postincrement
426  ValueMapConstIterator tmp = *this; ++*this; return tmp;
427  }
428 };
429 
430 } // end namespace llvm
431 
432 #endif // LLVM_IR_VALUEMAP_H
void clear()
Definition: ValueMap.h:146
This class represents lattice values for constants.
Definition: AllocatorList.h:23
std::pair< iterator, bool > insert(const std::pair< KeyT, ValueT > &KV)
Definition: ValueMap.h:173
static void onDelete(const ExtraDataT &, KeyT)
Definition: ValueMap.h:73
const void * getPointerIntoBucketsArray() const
getPointerIntoBucketsArray() - Return an opaque pointer into the buckets array.
Definition: ValueMap.h:221
void emplace(ArgTypes &&... Args)
Create a new object by constructing it in place with the given arguments.
Definition: Optional.h:237
This class defines the default behavior for configurable aspects of ValueMap<>.
Definition: ValueMap.h:57
ValueTypeProxy operator*() const
Definition: ValueMap.h:405
const void * getPointerIntoBucketsArray() const
getPointerIntoBucketsArray() - Return an opaque pointer into the buckets array.
Definition: DenseMap.h:325
const_iterator end() const
Definition: ValueMap.h:138
std::pair< iterator, bool > insert(const std::pair< KeyT, ValueT > &KV)
Definition: DenseMap.h:195
ValueMap(unsigned NumInitBuckets=64)
Definition: ValueMap.h:103
bool operator!=(const ValueMapConstIterator &RHS) const
Definition: ValueMap.h:417
APInt operator*(APInt a, uint64_t RHS)
Definition: APInt.h:2097
ValueMapConstIterator(ValueMapIterator< DenseMapT, KeyT > Other)
Definition: ValueMap.h:391
Key
PAL metadata keys.
std::pair< iterator, bool > insert(std::pair< KeyT, ValueT > &&KV)
Definition: ValueMap.h:178
iterator find(const KeyT &Val)
Definition: ValueMap.h:156
ValueT lookup(const KeyT &Val) const
lookup - Return the entry for the specified key, or a default constructed value if no such entry exis...
Definition: ValueMap.h:165
bool operator!=(const ValueMapIterator &RHS) const
Definition: ValueMap.h:365
value_type & FindAndConstruct(const KeyT &Key)
Definition: ValueMap.h:203
void allUsesReplacedWith(Value *new_key) override
Callback for Value RAUW.
Definition: ValueMap.h:271
bool isPointerIntoBucketsArray(const void *Ptr) const
isPointerIntoBucketsArray - Return true if the specified pointer points somewhere into the ValueMap&#39;s...
Definition: ValueMap.h:214
value_type & FindAndConstruct(const KeyT &Key)
Definition: DenseMap.h:291
iterator find(const_arg_type_t< KeyT > Val)
Definition: DenseMap.h:150
ValueMap(const ExtraData &Data, unsigned NumInitBuckets=64)
Definition: ValueMap.h:105
bool erase(const KeyT &Val)
Definition: DenseMap.h:272
Optional< Metadata * > getMappedMD(const Metadata *MD) const
Get the mapped metadata, if it&#39;s in the map.
Definition: ValueMap.h:123
ValueMapIterator & operator++()
Definition: ValueMap.h:369
std::pair< const Function *, FuncInfo > value_type
Definition: ValueMap.h:100
ValueTypeProxy operator->() const
Definition: ValueMap.h:358
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
const_iterator find(const KeyT &Val) const
Definition: ValueMap.h:159
Optional< MDMapT > & getMDMap()
Definition: ValueMap.h:120
static bool isEqual(const VH &LHS, const VH &RHS)
Definition: ValueMap.h:317
static mutex_type * getMutex(const ExtraDataT &)
Returns a mutex that should be acquired around any changes to the map.
Definition: ValueMap.h:80
unsigned size() const
Definition: DenseMap.h:99
const_iterator begin() const
Definition: ValueMap.h:137
ValueMapConstIterator operator++(int)
Definition: ValueMap.h:425
ValueMapIterator operator++(int)
Definition: ValueMap.h:373
bool hasMD() const
Definition: ValueMap.h:114
bool operator==(const ValueMapIterator &RHS) const
Definition: ValueMap.h:362
iterator end()
Definition: ValueMap.h:136
void insert(InputIt I, InputIt E)
insert - Range insertion of pairs.
Definition: ValueMap.h:186
static void onRAUW(const ExtraDataT &, KeyT, KeyT)
Definition: ValueMap.h:71
See the file comment.
Definition: ValueMap.h:85
ValueTypeProxy operator*() const
Definition: ValueMap.h:353
ValueMapIterator(BaseT I)
Definition: ValueMap.h:338
bool isPointerIntoBucketsArray(const void *Ptr) const
isPointerIntoBucketsArray - Return true if the specified pointer points somewhere into the DenseMap&#39;s...
Definition: DenseMap.h:318
bool empty() const
Definition: ValueMap.h:140
void erase(iterator I)
Definition: ValueMap.h:199
void resize(size_t Size)
Grow the map so that it has at least Size buckets. Does not shrink.
Definition: ValueMap.h:144
KeyT Unwrap() const
Definition: ValueMap.h:258
Target - Wrapper for Target specific information.
iterator begin()
Definition: DenseMap.h:73
#define I(x, y, z)
Definition: MD5.cpp:58
iterator end()
Definition: DenseMap.h:82
uint32_t Size
Definition: Profile.cpp:46
static bool isEqual(const KeyT &LHS, const VH &RHS)
Definition: ValueMap.h:321
LLVM_NODISCARD bool empty() const
Definition: DenseMap.h:96
size_type size() const
Definition: ValueMap.h:141
iterator find_as(const LookupKeyT &Val)
Alternate version of find() which allows a different, and possibly less expensive, key type.
Definition: DenseMap.h:169
void reset()
Definition: Optional.h:251
size_type count(const KeyT &Val) const
Return 1 if the specified key is in the map, 0 otherwise.
Definition: ValueMap.h:152
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
aarch64 promote const
BaseT base() const
Definition: ValueMap.h:340
LLVM Value Representation.
Definition: Value.h:73
ValueMapConstIterator & operator++()
Definition: ValueMap.h:421
Value handle with callbacks on RAUW and destruction.
Definition: ValueHandle.h:379
ValueTypeProxy operator->() const
Definition: ValueMap.h:410
ValueT & operator[](const KeyT &Key)
Definition: ValueMap.h:207
bool operator==(const ValueMapConstIterator &RHS) const
Definition: ValueMap.h:414
MDMapT & MD()
Definition: ValueMap.h:115
Root of the metadata hierarchy.
Definition: Metadata.h:57
void deleted() override
Callback for Value destruction.
Definition: ValueMap.h:260
iterator begin()
Definition: ValueMap.h:135
bool erase(const KeyT &Val)
Definition: ValueMap.h:191
Value * getValPtr() const
Definition: ValueHandle.h:95