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ValueMap.h
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1 //===- ValueMap.h - Safe map from Values to data ----------------*- 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 ValueMap class. ValueMap maps Value* or any subclass
11 // to an arbitrary other type. It provides the DenseMap interface but updates
12 // itself to remain safe when keys are RAUWed or deleted. By default, when a
13 // key is RAUWed from V1 to V2, the old mapping V1->target is removed, and a new
14 // mapping V2->target is added. If V2 already existed, its old target is
15 // overwritten. When a key is deleted, its mapping is removed.
16 //
17 // You can override a ValueMap's Config parameter to control exactly what
18 // happens on RAUW and destruction and to get called back on each event. It's
19 // legal to call back into the ValueMap from a Config's callbacks. Config
20 // parameters should inherit from ValueMapConfig<KeyT> to get default
21 // implementations of all the methods ValueMap uses. See ValueMapConfig for
22 // documentation of the functions you can override.
23 //
24 //===----------------------------------------------------------------------===//
25 
26 #ifndef LLVM_IR_VALUEMAP_H
27 #define LLVM_IR_VALUEMAP_H
28 
29 #include "llvm/ADT/DenseMap.h"
30 #include "llvm/ADT/DenseMapInfo.h"
31 #include "llvm/ADT/None.h"
32 #include "llvm/ADT/Optional.h"
33 #include "llvm/IR/TrackingMDRef.h"
34 #include "llvm/IR/ValueHandle.h"
35 #include "llvm/Support/Casting.h"
36 #include "llvm/Support/Mutex.h"
38 #include <algorithm>
39 #include <cassert>
40 #include <cstddef>
41 #include <iterator>
42 #include <type_traits>
43 #include <utility>
44 
45 namespace llvm {
46 
47 template<typename KeyT, typename ValueT, typename Config>
49 template<typename DenseMapT, typename KeyT>
51 template<typename DenseMapT, typename KeyT>
53 
54 /// This class defines the default behavior for configurable aspects of
55 /// ValueMap<>. User Configs should inherit from this class to be as compatible
56 /// as possible with future versions of ValueMap.
57 template<typename KeyT, typename MutexT = sys::Mutex>
59  using mutex_type = MutexT;
60 
61  /// If FollowRAUW is true, the ValueMap will update mappings on RAUW. If it's
62  /// false, the ValueMap will leave the original mapping in place.
63  enum { FollowRAUW = true };
64 
65  // All methods will be called with a first argument of type ExtraData. The
66  // default implementations in this class take a templated first argument so
67  // that users' subclasses can use any type they want without having to
68  // override all the defaults.
69  struct ExtraData {};
70 
71  template<typename ExtraDataT>
72  static void onRAUW(const ExtraDataT & /*Data*/, KeyT /*Old*/, KeyT /*New*/) {}
73  template<typename ExtraDataT>
74  static void onDelete(const ExtraDataT &/*Data*/, KeyT /*Old*/) {}
75 
76  /// Returns a mutex that should be acquired around any changes to the map.
77  /// This is only acquired from the CallbackVH (and held around calls to onRAUW
78  /// and onDelete) and not inside other ValueMap methods. NULL means that no
79  /// mutex is necessary.
80  template<typename ExtraDataT>
81  static mutex_type *getMutex(const ExtraDataT &/*Data*/) { return nullptr; }
82 };
83 
84 /// See the file comment.
85 template<typename KeyT, typename ValueT, typename Config =ValueMapConfig<KeyT>>
86 class ValueMap {
87  friend class ValueMapCallbackVH<KeyT, ValueT, Config>;
88 
92  using ExtraData = typename Config::ExtraData;
93 
94  MapT Map;
95  Optional<MDMapT> MDMap;
96  ExtraData Data;
97  bool MayMapMetadata = true;
98 
99 public:
100  using key_type = KeyT;
102  using value_type = std::pair<KeyT, ValueT>;
104 
105  explicit ValueMap(unsigned NumInitBuckets = 64)
106  : Map(NumInitBuckets), Data() {}
107  explicit ValueMap(const ExtraData &Data, unsigned NumInitBuckets = 64)
108  : Map(NumInitBuckets), Data(Data) {}
109  ValueMap(const ValueMap &) = delete;
110  ValueMap &operator=(const ValueMap &) = delete;
111 
112  bool hasMD() const { return bool(MDMap); }
113  MDMapT &MD() {
114  if (!MDMap)
115  MDMap.emplace();
116  return *MDMap;
117  }
118  Optional<MDMapT> &getMDMap() { return MDMap; }
119 
120  bool mayMapMetadata() const { return MayMapMetadata; }
121  void enableMapMetadata() { MayMapMetadata = true; }
122  void disableMapMetadata() { MayMapMetadata = false; }
123 
124  /// Get the mapped metadata, if it's in the map.
126  if (!MDMap)
127  return None;
128  auto Where = MDMap->find(MD);
129  if (Where == MDMap->end())
130  return None;
131  return Where->second.get();
132  }
133 
136 
137  inline iterator begin() { return iterator(Map.begin()); }
138  inline iterator end() { return iterator(Map.end()); }
139  inline const_iterator begin() const { return const_iterator(Map.begin()); }
140  inline const_iterator end() const { return const_iterator(Map.end()); }
141 
142  bool empty() const { return Map.empty(); }
143  size_type size() const { return Map.size(); }
144 
145  /// Grow the map so that it has at least Size buckets. Does not shrink
146  void resize(size_t Size) { Map.resize(Size); }
147 
148  void clear() {
149  Map.clear();
150  MDMap.reset();
151  }
152 
153  /// Return 1 if the specified key is in the map, 0 otherwise.
154  size_type count(const KeyT &Val) const {
155  return Map.find_as(Val) == Map.end() ? 0 : 1;
156  }
157 
158  iterator find(const KeyT &Val) {
159  return iterator(Map.find_as(Val));
160  }
161  const_iterator find(const KeyT &Val) const {
162  return const_iterator(Map.find_as(Val));
163  }
164 
165  /// lookup - Return the entry for the specified key, or a default
166  /// constructed value if no such entry exists.
167  ValueT lookup(const KeyT &Val) const {
168  typename MapT::const_iterator I = Map.find_as(Val);
169  return I != Map.end() ? I->second : ValueT();
170  }
171 
172  // Inserts key,value pair into the map if the key isn't already in the map.
173  // If the key is already in the map, it returns false and doesn't update the
174  // value.
175  std::pair<iterator, bool> insert(const std::pair<KeyT, ValueT> &KV) {
176  auto MapResult = Map.insert(std::make_pair(Wrap(KV.first), KV.second));
177  return std::make_pair(iterator(MapResult.first), MapResult.second);
178  }
179 
180  std::pair<iterator, bool> insert(std::pair<KeyT, ValueT> &&KV) {
181  auto MapResult =
182  Map.insert(std::make_pair(Wrap(KV.first), std::move(KV.second)));
183  return std::make_pair(iterator(MapResult.first), MapResult.second);
184  }
185 
186  /// insert - Range insertion of pairs.
187  template<typename InputIt>
188  void insert(InputIt I, InputIt E) {
189  for (; I != E; ++I)
190  insert(*I);
191  }
192 
193  bool erase(const KeyT &Val) {
194  typename MapT::iterator I = Map.find_as(Val);
195  if (I == Map.end())
196  return false;
197 
198  Map.erase(I);
199  return true;
200  }
201  void erase(iterator I) {
202  return Map.erase(I.base());
203  }
204 
206  return Map.FindAndConstruct(Wrap(Key));
207  }
208 
209  ValueT &operator[](const KeyT &Key) {
210  return Map[Wrap(Key)];
211  }
212 
213  /// isPointerIntoBucketsArray - Return true if the specified pointer points
214  /// somewhere into the ValueMap's array of buckets (i.e. either to a key or
215  /// value in the ValueMap).
216  bool isPointerIntoBucketsArray(const void *Ptr) const {
217  return Map.isPointerIntoBucketsArray(Ptr);
218  }
219 
220  /// getPointerIntoBucketsArray() - Return an opaque pointer into the buckets
221  /// array. In conjunction with the previous method, this can be used to
222  /// determine whether an insertion caused the ValueMap to reallocate.
223  const void *getPointerIntoBucketsArray() const {
224  return Map.getPointerIntoBucketsArray();
225  }
226 
227 private:
228  // Takes a key being looked up in the map and wraps it into a
229  // ValueMapCallbackVH, the actual key type of the map. We use a helper
230  // function because ValueMapCVH is constructed with a second parameter.
231  ValueMapCVH Wrap(KeyT key) const {
232  // The only way the resulting CallbackVH could try to modify *this (making
233  // the const_cast incorrect) is if it gets inserted into the map. But then
234  // this function must have been called from a non-const method, making the
235  // const_cast ok.
236  return ValueMapCVH(key, const_cast<ValueMap*>(this));
237  }
238 };
239 
240 // This CallbackVH updates its ValueMap when the contained Value changes,
241 // according to the user's preferences expressed through the Config object.
242 template <typename KeyT, typename ValueT, typename Config>
243 class ValueMapCallbackVH final : public CallbackVH {
244  friend class ValueMap<KeyT, ValueT, Config>;
246 
248  using KeySansPointerT = typename std::remove_pointer<KeyT>::type;
249 
250  ValueMapT *Map;
251 
252  ValueMapCallbackVH(KeyT Key, ValueMapT *Map)
253  : CallbackVH(const_cast<Value*>(static_cast<const Value*>(Key))),
254  Map(Map) {}
255 
256  // Private constructor used to create empty/tombstone DenseMap keys.
257  ValueMapCallbackVH(Value *V) : CallbackVH(V), Map(nullptr) {}
258 
259 public:
260  KeyT Unwrap() const { return cast_or_null<KeySansPointerT>(getValPtr()); }
261 
262  void deleted() override {
263  // Make a copy that won't get changed even when *this is destroyed.
264  ValueMapCallbackVH Copy(*this);
265  typename Config::mutex_type *M = Config::getMutex(Copy.Map->Data);
267  if (M)
269  Config::onDelete(Copy.Map->Data, Copy.Unwrap()); // May destroy *this.
270  Copy.Map->Map.erase(Copy); // Definitely destroys *this.
271  }
272 
273  void allUsesReplacedWith(Value *new_key) override {
274  assert(isa<KeySansPointerT>(new_key) &&
275  "Invalid RAUW on key of ValueMap<>");
276  // Make a copy that won't get changed even when *this is destroyed.
277  ValueMapCallbackVH Copy(*this);
278  typename Config::mutex_type *M = Config::getMutex(Copy.Map->Data);
280  if (M)
282 
283  KeyT typed_new_key = cast<KeySansPointerT>(new_key);
284  // Can destroy *this:
285  Config::onRAUW(Copy.Map->Data, Copy.Unwrap(), typed_new_key);
286  if (Config::FollowRAUW) {
287  typename ValueMapT::MapT::iterator I = Copy.Map->Map.find(Copy);
288  // I could == Copy.Map->Map.end() if the onRAUW callback already
289  // removed the old mapping.
290  if (I != Copy.Map->Map.end()) {
291  ValueT Target(std::move(I->second));
292  Copy.Map->Map.erase(I); // Definitely destroys *this.
293  Copy.Map->insert(std::make_pair(typed_new_key, std::move(Target)));
294  }
295  }
296  }
297 };
298 
299 template<typename KeyT, typename ValueT, typename Config>
300 struct DenseMapInfo<ValueMapCallbackVH<KeyT, ValueT, Config>> {
302 
303  static inline VH getEmptyKey() {
305  }
306 
307  static inline VH getTombstoneKey() {
309  }
310 
311  static unsigned getHashValue(const VH &Val) {
313  }
314 
315  static unsigned getHashValue(const KeyT &Val) {
317  }
318 
319  static bool isEqual(const VH &LHS, const VH &RHS) {
320  return LHS == RHS;
321  }
322 
323  static bool isEqual(const KeyT &LHS, const VH &RHS) {
324  return LHS == RHS.getValPtr();
325  }
326 };
327 
328 template<typename DenseMapT, typename KeyT>
329 class ValueMapIterator :
330  public std::iterator<std::forward_iterator_tag,
331  std::pair<KeyT, typename DenseMapT::mapped_type>,
332  ptrdiff_t> {
333  using BaseT = typename DenseMapT::iterator;
334  using ValueT = typename DenseMapT::mapped_type;
335 
336  BaseT I;
337 
338 public:
339  ValueMapIterator() : I() {}
340  ValueMapIterator(BaseT I) : I(I) {}
341 
342  BaseT base() const { return I; }
343 
344  struct ValueTypeProxy {
345  const KeyT first;
346  ValueT& second;
347 
348  ValueTypeProxy *operator->() { return this; }
349 
350  operator std::pair<KeyT, ValueT>() const {
351  return std::make_pair(first, second);
352  }
353  };
354 
356  ValueTypeProxy Result = {I->first.Unwrap(), I->second};
357  return Result;
358  }
359 
361  return operator*();
362  }
363 
364  bool operator==(const ValueMapIterator &RHS) const {
365  return I == RHS.I;
366  }
367  bool operator!=(const ValueMapIterator &RHS) const {
368  return I != RHS.I;
369  }
370 
371  inline ValueMapIterator& operator++() { // Preincrement
372  ++I;
373  return *this;
374  }
375  ValueMapIterator operator++(int) { // Postincrement
376  ValueMapIterator tmp = *this; ++*this; return tmp;
377  }
378 };
379 
380 template<typename DenseMapT, typename KeyT>
381 class ValueMapConstIterator :
382  public std::iterator<std::forward_iterator_tag,
383  std::pair<KeyT, typename DenseMapT::mapped_type>,
384  ptrdiff_t> {
385  using BaseT = typename DenseMapT::const_iterator;
386  using ValueT = typename DenseMapT::mapped_type;
387 
388  BaseT I;
389 
390 public:
392  ValueMapConstIterator(BaseT I) : I(I) {}
394  : I(Other.base()) {}
395 
396  BaseT base() const { return I; }
397 
398  struct ValueTypeProxy {
399  const KeyT first;
400  const ValueT& second;
401  ValueTypeProxy *operator->() { return this; }
402  operator std::pair<KeyT, ValueT>() const {
403  return std::make_pair(first, second);
404  }
405  };
406 
408  ValueTypeProxy Result = {I->first.Unwrap(), I->second};
409  return Result;
410  }
411 
413  return operator*();
414  }
415 
416  bool operator==(const ValueMapConstIterator &RHS) const {
417  return I == RHS.I;
418  }
419  bool operator!=(const ValueMapConstIterator &RHS) const {
420  return I != RHS.I;
421  }
422 
423  inline ValueMapConstIterator& operator++() { // Preincrement
424  ++I;
425  return *this;
426  }
427  ValueMapConstIterator operator++(int) { // Postincrement
428  ValueMapConstIterator tmp = *this; ++*this; return tmp;
429  }
430 };
431 
432 } // end namespace llvm
433 
434 #endif // LLVM_IR_VALUEMAP_H
void clear()
Definition: ValueMap.h:148
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
std::pair< iterator, bool > insert(const std::pair< KeyT, ValueT > &KV)
Definition: ValueMap.h:175
static void onDelete(const ExtraDataT &, KeyT)
Definition: ValueMap.h:74
const void * getPointerIntoBucketsArray() const
getPointerIntoBucketsArray() - Return an opaque pointer into the buckets array.
Definition: ValueMap.h:223
void emplace(ArgTypes &&... Args)
Create a new object by constructing it in place with the given arguments.
Definition: Optional.h:79
This class defines the default behavior for configurable aspects of ValueMap<>.
Definition: ValueMap.h:58
ValueTypeProxy operator*() const
Definition: ValueMap.h:407
const void * getPointerIntoBucketsArray() const
getPointerIntoBucketsArray() - Return an opaque pointer into the buckets array.
Definition: DenseMap.h:321
const_iterator end() const
Definition: ValueMap.h:140
std::pair< iterator, bool > insert(const std::pair< KeyT, ValueT > &KV)
Definition: DenseMap.h:191
ValueMap(unsigned NumInitBuckets=64)
Definition: ValueMap.h:105
bool operator!=(const ValueMapConstIterator &RHS) const
Definition: ValueMap.h:419
APInt operator*(APInt a, uint64_t RHS)
Definition: APInt.h:2070
ValueMapConstIterator(ValueMapIterator< DenseMapT, KeyT > Other)
Definition: ValueMap.h:393
Key
PAL metadata keys.
std::pair< iterator, bool > insert(std::pair< KeyT, ValueT > &&KV)
Definition: ValueMap.h:180
iterator find(const KeyT &Val)
Definition: ValueMap.h:158
void enableMapMetadata()
Definition: ValueMap.h:121
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:167
bool operator!=(const ValueMapIterator &RHS) const
Definition: ValueMap.h:367
value_type & FindAndConstruct(const KeyT &Key)
Definition: ValueMap.h:205
void allUsesReplacedWith(Value *new_key) override
Callback for Value RAUW.
Definition: ValueMap.h:273
bool isPointerIntoBucketsArray(const void *Ptr) const
isPointerIntoBucketsArray - Return true if the specified pointer points somewhere into the ValueMap&#39;s...
Definition: ValueMap.h:216
value_type & FindAndConstruct(const KeyT &Key)
Definition: DenseMap.h:287
iterator find(const_arg_type_t< KeyT > Val)
Definition: DenseMap.h:146
ValueMap(const ExtraData &Data, unsigned NumInitBuckets=64)
Definition: ValueMap.h:107
bool erase(const KeyT &Val)
Definition: DenseMap.h:268
Optional< Metadata * > getMappedMD(const Metadata *MD) const
Get the mapped metadata, if it&#39;s in the map.
Definition: ValueMap.h:125
ValueMapIterator & operator++()
Definition: ValueMap.h:371
std::pair< GlobalValue *, uint64_t > value_type
Definition: ValueMap.h:102
ValueTypeProxy operator->() const
Definition: ValueMap.h:360
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
const_iterator find(const KeyT &Val) const
Definition: ValueMap.h:161
Optional< MDMapT > & getMDMap()
Definition: ValueMap.h:118
static bool isEqual(const VH &LHS, const VH &RHS)
Definition: ValueMap.h:319
A pared-down imitation of std::unique_lock from C++11.
Definition: UniqueLock.h:29
static mutex_type * getMutex(const ExtraDataT &)
Returns a mutex that should be acquired around any changes to the map.
Definition: ValueMap.h:81
void disableMapMetadata()
Definition: ValueMap.h:122
unsigned size() const
Definition: DenseMap.h:96
const_iterator begin() const
Definition: ValueMap.h:139
ValueMapConstIterator operator++(int)
Definition: ValueMap.h:427
ValueMapIterator operator++(int)
Definition: ValueMap.h:375
bool hasMD() const
Definition: ValueMap.h:112
bool operator==(const ValueMapIterator &RHS) const
Definition: ValueMap.h:364
iterator end()
Definition: ValueMap.h:138
void insert(InputIt I, InputIt E)
insert - Range insertion of pairs.
Definition: ValueMap.h:188
static void onRAUW(const ExtraDataT &, KeyT, KeyT)
Definition: ValueMap.h:72
See the file comment.
Definition: ValueMap.h:86
ValueTypeProxy operator*() const
Definition: ValueMap.h:355
ValueMapIterator(BaseT I)
Definition: ValueMap.h:340
bool isPointerIntoBucketsArray(const void *Ptr) const
isPointerIntoBucketsArray - Return true if the specified pointer points somewhere into the DenseMap&#39;s...
Definition: DenseMap.h:314
bool empty() const
Definition: ValueMap.h:142
void erase(iterator I)
Definition: ValueMap.h:201
void resize(size_t Size)
Grow the map so that it has at least Size buckets. Does not shrink.
Definition: ValueMap.h:146
KeyT Unwrap() const
Definition: ValueMap.h:260
Target - Wrapper for Target specific information.
iterator begin()
Definition: DenseMap.h:70
#define I(x, y, z)
Definition: MD5.cpp:58
iterator end()
Definition: DenseMap.h:79
static bool isEqual(const KeyT &LHS, const VH &RHS)
Definition: ValueMap.h:323
bool mayMapMetadata() const
Definition: ValueMap.h:120
LLVM_NODISCARD bool empty() const
Definition: DenseMap.h:93
size_type size() const
Definition: ValueMap.h:143
iterator find_as(const LookupKeyT &Val)
Alternate version of find() which allows a different, and possibly less expensive, key type.
Definition: DenseMap.h:165
void reset()
Definition: Optional.h:112
size_type count(const KeyT &Val) const
Return 1 if the specified key is in the map, 0 otherwise.
Definition: ValueMap.h:154
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
aarch64 promote const
BaseT base() const
Definition: ValueMap.h:342
LLVM Value Representation.
Definition: Value.h:73
constexpr char Size[]
Key for Kernel::Arg::Metadata::mSize.
ValueMapConstIterator & operator++()
Definition: ValueMap.h:423
Value handle with callbacks on RAUW and destruction.
Definition: ValueHandle.h:389
ValueTypeProxy operator->() const
Definition: ValueMap.h:412
ValueT & operator[](const KeyT &Key)
Definition: ValueMap.h:209
bool operator==(const ValueMapConstIterator &RHS) const
Definition: ValueMap.h:416
MDMapT & MD()
Definition: ValueMap.h:113
Root of the metadata hierarchy.
Definition: Metadata.h:58
void deleted() override
Callback for Value destruction.
Definition: ValueMap.h:262
iterator begin()
Definition: ValueMap.h:137
bool erase(const KeyT &Val)
Definition: ValueMap.h:193
Value * getValPtr() const
Definition: ValueHandle.h:96