LLVM  7.0.0svn
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 can't be copied nor moved, beucase the callbacks store pointer
110  // to it.
111  ValueMap(const ValueMap &) = delete;
112  ValueMap(ValueMap &&) = delete;
113  ValueMap &operator=(const ValueMap &) = delete;
114  ValueMap &operator=(ValueMap &&) = delete;
115 
116  bool hasMD() const { return bool(MDMap); }
117  MDMapT &MD() {
118  if (!MDMap)
119  MDMap.emplace();
120  return *MDMap;
121  }
122  Optional<MDMapT> &getMDMap() { return MDMap; }
123 
124  bool mayMapMetadata() const { return MayMapMetadata; }
125  void enableMapMetadata() { MayMapMetadata = true; }
126  void disableMapMetadata() { MayMapMetadata = false; }
127 
128  /// Get the mapped metadata, if it's in the map.
130  if (!MDMap)
131  return None;
132  auto Where = MDMap->find(MD);
133  if (Where == MDMap->end())
134  return None;
135  return Where->second.get();
136  }
137 
140 
141  inline iterator begin() { return iterator(Map.begin()); }
142  inline iterator end() { return iterator(Map.end()); }
143  inline const_iterator begin() const { return const_iterator(Map.begin()); }
144  inline const_iterator end() const { return const_iterator(Map.end()); }
145 
146  bool empty() const { return Map.empty(); }
147  size_type size() const { return Map.size(); }
148 
149  /// Grow the map so that it has at least Size buckets. Does not shrink
150  void resize(size_t Size) { Map.resize(Size); }
151 
152  void clear() {
153  Map.clear();
154  MDMap.reset();
155  }
156 
157  /// Return 1 if the specified key is in the map, 0 otherwise.
158  size_type count(const KeyT &Val) const {
159  return Map.find_as(Val) == Map.end() ? 0 : 1;
160  }
161 
162  iterator find(const KeyT &Val) {
163  return iterator(Map.find_as(Val));
164  }
165  const_iterator find(const KeyT &Val) const {
166  return const_iterator(Map.find_as(Val));
167  }
168 
169  /// lookup - Return the entry for the specified key, or a default
170  /// constructed value if no such entry exists.
171  ValueT lookup(const KeyT &Val) const {
172  typename MapT::const_iterator I = Map.find_as(Val);
173  return I != Map.end() ? I->second : ValueT();
174  }
175 
176  // Inserts key,value pair into the map if the key isn't already in the map.
177  // If the key is already in the map, it returns false and doesn't update the
178  // value.
179  std::pair<iterator, bool> insert(const std::pair<KeyT, ValueT> &KV) {
180  auto MapResult = Map.insert(std::make_pair(Wrap(KV.first), KV.second));
181  return std::make_pair(iterator(MapResult.first), MapResult.second);
182  }
183 
184  std::pair<iterator, bool> insert(std::pair<KeyT, ValueT> &&KV) {
185  auto MapResult =
186  Map.insert(std::make_pair(Wrap(KV.first), std::move(KV.second)));
187  return std::make_pair(iterator(MapResult.first), MapResult.second);
188  }
189 
190  /// insert - Range insertion of pairs.
191  template<typename InputIt>
192  void insert(InputIt I, InputIt E) {
193  for (; I != E; ++I)
194  insert(*I);
195  }
196 
197  bool erase(const KeyT &Val) {
198  typename MapT::iterator I = Map.find_as(Val);
199  if (I == Map.end())
200  return false;
201 
202  Map.erase(I);
203  return true;
204  }
205  void erase(iterator I) {
206  return Map.erase(I.base());
207  }
208 
210  return Map.FindAndConstruct(Wrap(Key));
211  }
212 
213  ValueT &operator[](const KeyT &Key) {
214  return Map[Wrap(Key)];
215  }
216 
217  /// isPointerIntoBucketsArray - Return true if the specified pointer points
218  /// somewhere into the ValueMap's array of buckets (i.e. either to a key or
219  /// value in the ValueMap).
220  bool isPointerIntoBucketsArray(const void *Ptr) const {
221  return Map.isPointerIntoBucketsArray(Ptr);
222  }
223 
224  /// getPointerIntoBucketsArray() - Return an opaque pointer into the buckets
225  /// array. In conjunction with the previous method, this can be used to
226  /// determine whether an insertion caused the ValueMap to reallocate.
227  const void *getPointerIntoBucketsArray() const {
228  return Map.getPointerIntoBucketsArray();
229  }
230 
231 private:
232  // Takes a key being looked up in the map and wraps it into a
233  // ValueMapCallbackVH, the actual key type of the map. We use a helper
234  // function because ValueMapCVH is constructed with a second parameter.
235  ValueMapCVH Wrap(KeyT key) const {
236  // The only way the resulting CallbackVH could try to modify *this (making
237  // the const_cast incorrect) is if it gets inserted into the map. But then
238  // this function must have been called from a non-const method, making the
239  // const_cast ok.
240  return ValueMapCVH(key, const_cast<ValueMap*>(this));
241  }
242 };
243 
244 // This CallbackVH updates its ValueMap when the contained Value changes,
245 // according to the user's preferences expressed through the Config object.
246 template <typename KeyT, typename ValueT, typename Config>
247 class ValueMapCallbackVH final : public CallbackVH {
248  friend class ValueMap<KeyT, ValueT, Config>;
250 
252  using KeySansPointerT = typename std::remove_pointer<KeyT>::type;
253 
254  ValueMapT *Map;
255 
256  ValueMapCallbackVH(KeyT Key, ValueMapT *Map)
257  : CallbackVH(const_cast<Value*>(static_cast<const Value*>(Key))),
258  Map(Map) {}
259 
260  // Private constructor used to create empty/tombstone DenseMap keys.
261  ValueMapCallbackVH(Value *V) : CallbackVH(V), Map(nullptr) {}
262 
263 public:
264  KeyT Unwrap() const { return cast_or_null<KeySansPointerT>(getValPtr()); }
265 
266  void deleted() override {
267  // Make a copy that won't get changed even when *this is destroyed.
268  ValueMapCallbackVH Copy(*this);
269  typename Config::mutex_type *M = Config::getMutex(Copy.Map->Data);
271  if (M)
273  Config::onDelete(Copy.Map->Data, Copy.Unwrap()); // May destroy *this.
274  Copy.Map->Map.erase(Copy); // Definitely destroys *this.
275  }
276 
277  void allUsesReplacedWith(Value *new_key) override {
278  assert(isa<KeySansPointerT>(new_key) &&
279  "Invalid RAUW on key of ValueMap<>");
280  // Make a copy that won't get changed even when *this is destroyed.
281  ValueMapCallbackVH Copy(*this);
282  typename Config::mutex_type *M = Config::getMutex(Copy.Map->Data);
284  if (M)
286 
287  KeyT typed_new_key = cast<KeySansPointerT>(new_key);
288  // Can destroy *this:
289  Config::onRAUW(Copy.Map->Data, Copy.Unwrap(), typed_new_key);
290  if (Config::FollowRAUW) {
291  typename ValueMapT::MapT::iterator I = Copy.Map->Map.find(Copy);
292  // I could == Copy.Map->Map.end() if the onRAUW callback already
293  // removed the old mapping.
294  if (I != Copy.Map->Map.end()) {
295  ValueT Target(std::move(I->second));
296  Copy.Map->Map.erase(I); // Definitely destroys *this.
297  Copy.Map->insert(std::make_pair(typed_new_key, std::move(Target)));
298  }
299  }
300  }
301 };
302 
303 template<typename KeyT, typename ValueT, typename Config>
304 struct DenseMapInfo<ValueMapCallbackVH<KeyT, ValueT, Config>> {
306 
307  static inline VH getEmptyKey() {
309  }
310 
311  static inline VH getTombstoneKey() {
313  }
314 
315  static unsigned getHashValue(const VH &Val) {
317  }
318 
319  static unsigned getHashValue(const KeyT &Val) {
321  }
322 
323  static bool isEqual(const VH &LHS, const VH &RHS) {
324  return LHS == RHS;
325  }
326 
327  static bool isEqual(const KeyT &LHS, const VH &RHS) {
328  return LHS == RHS.getValPtr();
329  }
330 };
331 
332 template<typename DenseMapT, typename KeyT>
333 class ValueMapIterator :
334  public std::iterator<std::forward_iterator_tag,
335  std::pair<KeyT, typename DenseMapT::mapped_type>,
336  ptrdiff_t> {
337  using BaseT = typename DenseMapT::iterator;
338  using ValueT = typename DenseMapT::mapped_type;
339 
340  BaseT I;
341 
342 public:
343  ValueMapIterator() : I() {}
344  ValueMapIterator(BaseT I) : I(I) {}
345 
346  BaseT base() const { return I; }
347 
348  struct ValueTypeProxy {
349  const KeyT first;
350  ValueT& second;
351 
352  ValueTypeProxy *operator->() { return this; }
353 
354  operator std::pair<KeyT, ValueT>() const {
355  return std::make_pair(first, second);
356  }
357  };
358 
360  ValueTypeProxy Result = {I->first.Unwrap(), I->second};
361  return Result;
362  }
363 
365  return operator*();
366  }
367 
368  bool operator==(const ValueMapIterator &RHS) const {
369  return I == RHS.I;
370  }
371  bool operator!=(const ValueMapIterator &RHS) const {
372  return I != RHS.I;
373  }
374 
375  inline ValueMapIterator& operator++() { // Preincrement
376  ++I;
377  return *this;
378  }
379  ValueMapIterator operator++(int) { // Postincrement
380  ValueMapIterator tmp = *this; ++*this; return tmp;
381  }
382 };
383 
384 template<typename DenseMapT, typename KeyT>
385 class ValueMapConstIterator :
386  public std::iterator<std::forward_iterator_tag,
387  std::pair<KeyT, typename DenseMapT::mapped_type>,
388  ptrdiff_t> {
389  using BaseT = typename DenseMapT::const_iterator;
390  using ValueT = typename DenseMapT::mapped_type;
391 
392  BaseT I;
393 
394 public:
396  ValueMapConstIterator(BaseT I) : I(I) {}
398  : I(Other.base()) {}
399 
400  BaseT base() const { return I; }
401 
402  struct ValueTypeProxy {
403  const KeyT first;
404  const ValueT& second;
405  ValueTypeProxy *operator->() { return this; }
406  operator std::pair<KeyT, ValueT>() const {
407  return std::make_pair(first, second);
408  }
409  };
410 
412  ValueTypeProxy Result = {I->first.Unwrap(), I->second};
413  return Result;
414  }
415 
417  return operator*();
418  }
419 
420  bool operator==(const ValueMapConstIterator &RHS) const {
421  return I == RHS.I;
422  }
423  bool operator!=(const ValueMapConstIterator &RHS) const {
424  return I != RHS.I;
425  }
426 
427  inline ValueMapConstIterator& operator++() { // Preincrement
428  ++I;
429  return *this;
430  }
431  ValueMapConstIterator operator++(int) { // Postincrement
432  ValueMapConstIterator tmp = *this; ++*this; return tmp;
433  }
434 };
435 
436 } // end namespace llvm
437 
438 #endif // LLVM_IR_VALUEMAP_H
void clear()
Definition: ValueMap.h:152
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:179
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:227
void emplace(ArgTypes &&... Args)
Create a new object by constructing it in place with the given arguments.
Definition: Optional.h:153
This class defines the default behavior for configurable aspects of ValueMap<>.
Definition: ValueMap.h:58
ValueTypeProxy operator*() const
Definition: ValueMap.h:411
const void * getPointerIntoBucketsArray() const
getPointerIntoBucketsArray() - Return an opaque pointer into the buckets array.
Definition: DenseMap.h:321
const_iterator end() const
Definition: ValueMap.h:144
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:423
APInt operator*(APInt a, uint64_t RHS)
Definition: APInt.h:2070
ValueMapConstIterator(ValueMapIterator< DenseMapT, KeyT > Other)
Definition: ValueMap.h:397
Key
PAL metadata keys.
std::pair< iterator, bool > insert(std::pair< KeyT, ValueT > &&KV)
Definition: ValueMap.h:184
iterator find(const KeyT &Val)
Definition: ValueMap.h:162
void enableMapMetadata()
Definition: ValueMap.h:125
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:171
bool operator!=(const ValueMapIterator &RHS) const
Definition: ValueMap.h:371
value_type & FindAndConstruct(const KeyT &Key)
Definition: ValueMap.h:209
void allUsesReplacedWith(Value *new_key) override
Callback for Value RAUW.
Definition: ValueMap.h:277
bool isPointerIntoBucketsArray(const void *Ptr) const
isPointerIntoBucketsArray - Return true if the specified pointer points somewhere into the ValueMap&#39;s...
Definition: ValueMap.h:220
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:129
ValueMapIterator & operator++()
Definition: ValueMap.h:375
std::pair< GlobalValue *, uint64_t > value_type
Definition: ValueMap.h:102
ValueTypeProxy operator->() const
Definition: ValueMap.h:364
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
const_iterator find(const KeyT &Val) const
Definition: ValueMap.h:165
Optional< MDMapT > & getMDMap()
Definition: ValueMap.h:122
static bool isEqual(const VH &LHS, const VH &RHS)
Definition: ValueMap.h:323
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:126
unsigned size() const
Definition: DenseMap.h:96
const_iterator begin() const
Definition: ValueMap.h:143
ValueMapConstIterator operator++(int)
Definition: ValueMap.h:431
ValueMapIterator operator++(int)
Definition: ValueMap.h:379
bool hasMD() const
Definition: ValueMap.h:116
bool operator==(const ValueMapIterator &RHS) const
Definition: ValueMap.h:368
iterator end()
Definition: ValueMap.h:142
void insert(InputIt I, InputIt E)
insert - Range insertion of pairs.
Definition: ValueMap.h:192
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:359
ValueMapIterator(BaseT I)
Definition: ValueMap.h:344
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:146
void erase(iterator I)
Definition: ValueMap.h:205
void resize(size_t Size)
Grow the map so that it has at least Size buckets. Does not shrink.
Definition: ValueMap.h:150
KeyT Unwrap() const
Definition: ValueMap.h:264
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:327
bool mayMapMetadata() const
Definition: ValueMap.h:124
LLVM_NODISCARD bool empty() const
Definition: DenseMap.h:93
size_type size() const
Definition: ValueMap.h:147
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:169
size_type count(const KeyT &Val) const
Return 1 if the specified key is in the map, 0 otherwise.
Definition: ValueMap.h:158
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
aarch64 promote const
BaseT base() const
Definition: ValueMap.h:346
LLVM Value Representation.
Definition: Value.h:73
constexpr char Size[]
Key for Kernel::Arg::Metadata::mSize.
ValueMapConstIterator & operator++()
Definition: ValueMap.h:427
Value handle with callbacks on RAUW and destruction.
Definition: ValueHandle.h:389
ValueTypeProxy operator->() const
Definition: ValueMap.h:416
ValueT & operator[](const KeyT &Key)
Definition: ValueMap.h:213
bool operator==(const ValueMapConstIterator &RHS) const
Definition: ValueMap.h:420
MDMapT & MD()
Definition: ValueMap.h:117
Root of the metadata hierarchy.
Definition: Metadata.h:58
void deleted() override
Callback for Value destruction.
Definition: ValueMap.h:266
iterator begin()
Definition: ValueMap.h:141
bool erase(const KeyT &Val)
Definition: ValueMap.h:197
Value * getValPtr() const
Definition: ValueHandle.h:96