1//===-- llvm/ADT/FoldingSet.h - Uniquing Hash Set ---------------*- 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 a hash set that can be used to remove duplication of nodes 11// in a graph. This code was originally created by Chris Lattner for use with 12// SelectionDAGCSEMap, but was isolated to provide use across the llvm code set. 13// 14//===----------------------------------------------------------------------===// 15 16#ifndef LLVM_ADT_FOLDINGSET_H 17#define LLVM_ADT_FOLDINGSET_H 18 19#include "llvm/ADT/SmallVector.h" 20#include "llvm/ADT/iterator.h" 21#include "llvm/Support/Allocator.h" 22 23namespace llvm { 24/// This folding set used for two purposes: 25/// 1. Given information about a node we want to create, look up the unique 26/// instance of the node in the set. If the node already exists, return 27/// it, otherwise return the bucket it should be inserted into. 28/// 2. Given a node that has already been created, remove it from the set. 29/// 30/// This class is implemented as a single-link chained hash table, where the 31/// "buckets" are actually the nodes themselves (the next pointer is in the 32/// node). The last node points back to the bucket to simplify node removal. 33/// 34/// Any node that is to be included in the folding set must be a subclass of 35/// FoldingSetNode. The node class must also define a Profile method used to 36/// establish the unique bits of data for the node. The Profile method is 37/// passed a FoldingSetNodeID object which is used to gather the bits. Just 38/// call one of the Add* functions defined in the FoldingSetImpl::NodeID class. 39/// NOTE: That the folding set does not own the nodes and it is the 40/// responsibility of the user to dispose of the nodes. 41/// 42/// Eg. 43/// class MyNode : public FoldingSetNode { 44/// private: 45/// std::string Name; 46/// unsigned Value; 47/// public: 48/// MyNode(const char *N, unsigned V) : Name(N), Value(V) {} 49/// ... 50/// void Profile(FoldingSetNodeID &ID) const { 51/// ID.AddString(Name); 52/// ID.AddInteger(Value); 53/// } 54/// ... 55/// }; 56/// 57/// To define the folding set itself use the FoldingSet template; 58/// 59/// Eg. 60/// FoldingSet<MyNode> MyFoldingSet; 61/// 62/// Four public methods are available to manipulate the folding set; 63/// 64/// 1) If you have an existing node that you want add to the set but unsure 65/// that the node might already exist then call; 66/// 67/// MyNode *M = MyFoldingSet.GetOrInsertNode(N); 68/// 69/// If The result is equal to the input then the node has been inserted. 70/// Otherwise, the result is the node existing in the folding set, and the 71/// input can be discarded (use the result instead.) 72/// 73/// 2) If you are ready to construct a node but want to check if it already 74/// exists, then call FindNodeOrInsertPos with a FoldingSetNodeID of the bits to 75/// check; 76/// 77/// FoldingSetNodeID ID; 78/// ID.AddString(Name); 79/// ID.AddInteger(Value); 80/// void *InsertPoint; 81/// 82/// MyNode *M = MyFoldingSet.FindNodeOrInsertPos(ID, InsertPoint); 83/// 84/// If found then M with be non-NULL, else InsertPoint will point to where it 85/// should be inserted using InsertNode. 86/// 87/// 3) If you get a NULL result from FindNodeOrInsertPos then you can as a new 88/// node with FindNodeOrInsertPos; 89/// 90/// InsertNode(N, InsertPoint); 91/// 92/// 4) Finally, if you want to remove a node from the folding set call; 93/// 94/// bool WasRemoved = RemoveNode(N); 95/// 96/// The result indicates whether the node existed in the folding set. 97 98class FoldingSetNodeID; 99class StringRef; 100 101//===----------------------------------------------------------------------===// 102/// FoldingSetImpl - Implements the folding set functionality. The main 103/// structure is an array of buckets. Each bucket is indexed by the hash of 104/// the nodes it contains. The bucket itself points to the nodes contained 105/// in the bucket via a singly linked list. The last node in the list points 106/// back to the bucket to facilitate node removal. 107/// 108class FoldingSetImpl { 109 virtual void anchor(); // Out of line virtual method. 110 111protected: 112 /// Buckets - Array of bucket chains. 113 /// 114 void **Buckets; 115 116 /// NumBuckets - Length of the Buckets array. Always a power of 2. 117 /// 118 unsigned NumBuckets; 119 120 /// NumNodes - Number of nodes in the folding set. Growth occurs when NumNodes 121 /// is greater than twice the number of buckets. 122 unsigned NumNodes; 123 124 explicit FoldingSetImpl(unsigned Log2InitSize = 6); 125 FoldingSetImpl(FoldingSetImpl &&Arg); 126 FoldingSetImpl &operator=(FoldingSetImpl &&RHS); 127 ~FoldingSetImpl(); 128 129public: 130 //===--------------------------------------------------------------------===// 131 /// Node - This class is used to maintain the singly linked bucket list in 132 /// a folding set. 133 /// 134 class Node { 135 private: 136 // NextInFoldingSetBucket - next link in the bucket list. 137 void *NextInFoldingSetBucket; 138 139 public: 140 Node() : NextInFoldingSetBucket(nullptr) {} 141 142 // Accessors 143 void *getNextInBucket() const { return NextInFoldingSetBucket; } 144 void SetNextInBucket(void *N) { NextInFoldingSetBucket = N; } 145 }; 146 147 /// clear - Remove all nodes from the folding set. 148 void clear(); 149 150 /// RemoveNode - Remove a node from the folding set, returning true if one 151 /// was removed or false if the node was not in the folding set. 152 bool RemoveNode(Node *N); 153 154 /// GetOrInsertNode - If there is an existing simple Node exactly 155 /// equal to the specified node, return it. Otherwise, insert 'N' and return 156 /// it instead. 157 Node *GetOrInsertNode(Node *N); 158 159 /// FindNodeOrInsertPos - Look up the node specified by ID. If it exists, 160 /// return it. If not, return the insertion token that will make insertion 161 /// faster. 162 Node *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos); 163 164 /// InsertNode - Insert the specified node into the folding set, knowing that 165 /// it is not already in the folding set. InsertPos must be obtained from 166 /// FindNodeOrInsertPos. 167 void InsertNode(Node *N, void *InsertPos); 168 169 /// InsertNode - Insert the specified node into the folding set, knowing that 170 /// it is not already in the folding set. 171 void InsertNode(Node *N) { 172 Node *Inserted = GetOrInsertNode(N); 173 (void)Inserted; 174 assert(Inserted == N && "Node already inserted!"); 175 } 176 177 /// size - Returns the number of nodes in the folding set. 178 unsigned size() const { return NumNodes; } 179 180 /// empty - Returns true if there are no nodes in the folding set. 181 bool empty() const { return NumNodes == 0; } 182 183 /// reserve - Increase the number of buckets such that adding the 184 /// EltCount-th node won't cause a rebucket operation. reserve is permitted 185 /// to allocate more space than requested by EltCount. 186 void reserve(unsigned EltCount); 187 /// capacity - Returns the number of nodes permitted in the folding set 188 /// before a rebucket operation is performed. 189 unsigned capacity() { 190 // We allow a load factor of up to 2.0, 191 // so that means our capacity is NumBuckets * 2 192 return NumBuckets * 2; 193 } 194 195private: 196 /// GrowHashTable - Double the size of the hash table and rehash everything. 197 void GrowHashTable(); 198 199 /// GrowBucketCount - resize the hash table and rehash everything. 200 /// NewBucketCount must be a power of two, and must be greater than the old 201 /// bucket count. 202 void GrowBucketCount(unsigned NewBucketCount); 203protected: 204 /// GetNodeProfile - Instantiations of the FoldingSet template implement 205 /// this function to gather data bits for the given node. 206 virtual void GetNodeProfile(Node *N, FoldingSetNodeID &ID) const = 0; 207 /// NodeEquals - Instantiations of the FoldingSet template implement 208 /// this function to compare the given node with the given ID. 209 virtual bool NodeEquals(Node *N, const FoldingSetNodeID &ID, unsigned IDHash, 210 FoldingSetNodeID &TempID) const=0; 211 /// ComputeNodeHash - Instantiations of the FoldingSet template implement 212 /// this function to compute a hash value for the given node. 213 virtual unsigned ComputeNodeHash(Node *N, FoldingSetNodeID &TempID) const = 0; 214}; 215 216//===----------------------------------------------------------------------===// 217 218template<typename T> struct FoldingSetTrait; 219 220/// DefaultFoldingSetTrait - This class provides default implementations 221/// for FoldingSetTrait implementations. 222/// 223template<typename T> struct DefaultFoldingSetTrait { 224 static void Profile(const T &X, FoldingSetNodeID &ID) { 225 X.Profile(ID); 226 } 227 static void Profile(T &X, FoldingSetNodeID &ID) { 228 X.Profile(ID); 229 } 230 231 // Equals - Test if the profile for X would match ID, using TempID 232 // to compute a temporary ID if necessary. The default implementation 233 // just calls Profile and does a regular comparison. Implementations 234 // can override this to provide more efficient implementations. 235 static inline bool Equals(T &X, const FoldingSetNodeID &ID, unsigned IDHash, 236 FoldingSetNodeID &TempID); 237 238 // ComputeHash - Compute a hash value for X, using TempID to 239 // compute a temporary ID if necessary. The default implementation 240 // just calls Profile and does a regular hash computation. 241 // Implementations can override this to provide more efficient 242 // implementations. 243 static inline unsigned ComputeHash(T &X, FoldingSetNodeID &TempID); 244}; 245 246/// FoldingSetTrait - This trait class is used to define behavior of how 247/// to "profile" (in the FoldingSet parlance) an object of a given type. 248/// The default behavior is to invoke a 'Profile' method on an object, but 249/// through template specialization the behavior can be tailored for specific 250/// types. Combined with the FoldingSetNodeWrapper class, one can add objects 251/// to FoldingSets that were not originally designed to have that behavior. 252template<typename T> struct FoldingSetTrait 253 : public DefaultFoldingSetTrait<T> {}; 254 255template<typename T, typename Ctx> struct ContextualFoldingSetTrait; 256 257/// DefaultContextualFoldingSetTrait - Like DefaultFoldingSetTrait, but 258/// for ContextualFoldingSets. 259template<typename T, typename Ctx> 260struct DefaultContextualFoldingSetTrait { 261 static void Profile(T &X, FoldingSetNodeID &ID, Ctx Context) { 262 X.Profile(ID, Context); 263 } 264 static inline bool Equals(T &X, const FoldingSetNodeID &ID, unsigned IDHash, 265 FoldingSetNodeID &TempID, Ctx Context); 266 static inline unsigned ComputeHash(T &X, FoldingSetNodeID &TempID, 267 Ctx Context); 268}; 269 270/// ContextualFoldingSetTrait - Like FoldingSetTrait, but for 271/// ContextualFoldingSets. 272template<typename T, typename Ctx> struct ContextualFoldingSetTrait 273 : public DefaultContextualFoldingSetTrait<T, Ctx> {}; 274 275//===--------------------------------------------------------------------===// 276/// FoldingSetNodeIDRef - This class describes a reference to an interned 277/// FoldingSetNodeID, which can be a useful to store node id data rather 278/// than using plain FoldingSetNodeIDs, since the 32-element SmallVector 279/// is often much larger than necessary, and the possibility of heap 280/// allocation means it requires a non-trivial destructor call. 281class FoldingSetNodeIDRef { 282 const unsigned *Data; 283 size_t Size; 284 285public: 286 FoldingSetNodeIDRef() : Data(nullptr), Size(0) {} 287 FoldingSetNodeIDRef(const unsigned *D, size_t S) : Data(D), Size(S) {} 288 289 /// ComputeHash - Compute a strong hash value for this FoldingSetNodeIDRef, 290 /// used to lookup the node in the FoldingSetImpl. 291 unsigned ComputeHash() const; 292 293 bool operator==(FoldingSetNodeIDRef) const; 294 295 bool operator!=(FoldingSetNodeIDRef RHS) const { return !(*this == RHS); } 296 297 /// Used to compare the "ordering" of two nodes as defined by the 298 /// profiled bits and their ordering defined by memcmp(). 299 bool operator<(FoldingSetNodeIDRef) const; 300 301 const unsigned *getData() const { return Data; } 302 size_t getSize() const { return Size; } 303}; 304 305//===--------------------------------------------------------------------===// 306/// FoldingSetNodeID - This class is used to gather all the unique data bits of 307/// a node. When all the bits are gathered this class is used to produce a 308/// hash value for the node. 309/// 310class FoldingSetNodeID { 311 /// Bits - Vector of all the data bits that make the node unique. 312 /// Use a SmallVector to avoid a heap allocation in the common case. 313 SmallVector<unsigned, 32> Bits; 314 315public: 316 FoldingSetNodeID() {} 317 318 FoldingSetNodeID(FoldingSetNodeIDRef Ref) 319 : Bits(Ref.getData(), Ref.getData() + Ref.getSize()) {} 320 321 /// Add* - Add various data types to Bit data. 322 /// 323 void AddPointer(const void *Ptr); 324 void AddInteger(signed I); 325 void AddInteger(unsigned I); 326 void AddInteger(long I); 327 void AddInteger(unsigned long I); 328 void AddInteger(long long I); 329 void AddInteger(unsigned long long I); 330 void AddBoolean(bool B) { AddInteger(B ? 1U : 0U); } 331 void AddString(StringRef String); 332 void AddNodeID(const FoldingSetNodeID &ID); 333 334 template <typename T> 335 inline void Add(const T &x) { FoldingSetTrait<T>::Profile(x, *this); } 336 337 /// clear - Clear the accumulated profile, allowing this FoldingSetNodeID 338 /// object to be used to compute a new profile. 339 inline void clear() { Bits.clear(); } 340 341 /// ComputeHash - Compute a strong hash value for this FoldingSetNodeID, used 342 /// to lookup the node in the FoldingSetImpl. 343 unsigned ComputeHash() const; 344 345 /// operator== - Used to compare two nodes to each other. 346 /// 347 bool operator==(const FoldingSetNodeID &RHS) const; 348 bool operator==(const FoldingSetNodeIDRef RHS) const; 349 350 bool operator!=(const FoldingSetNodeID &RHS) const { return !(*this == RHS); } 351 bool operator!=(const FoldingSetNodeIDRef RHS) const { return !(*this ==RHS);} 352 353 /// Used to compare the "ordering" of two nodes as defined by the 354 /// profiled bits and their ordering defined by memcmp(). 355 bool operator<(const FoldingSetNodeID &RHS) const; 356 bool operator<(const FoldingSetNodeIDRef RHS) const; 357 358 /// Intern - Copy this node's data to a memory region allocated from the 359 /// given allocator and return a FoldingSetNodeIDRef describing the 360 /// interned data. 361 FoldingSetNodeIDRef Intern(BumpPtrAllocator &Allocator) const; 362}; 363 364// Convenience type to hide the implementation of the folding set. 365typedef FoldingSetImpl::Node FoldingSetNode; 366template<class T> class FoldingSetIterator; 367template<class T> class FoldingSetBucketIterator; 368 369// Definitions of FoldingSetTrait and ContextualFoldingSetTrait functions, which 370// require the definition of FoldingSetNodeID. 371template<typename T> 372inline bool 373DefaultFoldingSetTrait<T>::Equals(T &X, const FoldingSetNodeID &ID, 374 unsigned /*IDHash*/, 375 FoldingSetNodeID &TempID) { 376 FoldingSetTrait<T>::Profile(X, TempID); 377 return TempID == ID; 378} 379template<typename T> 380inline unsigned 381DefaultFoldingSetTrait<T>::ComputeHash(T &X, FoldingSetNodeID &TempID) { 382 FoldingSetTrait<T>::Profile(X, TempID); 383 return TempID.ComputeHash(); 384} 385template<typename T, typename Ctx> 386inline bool 387DefaultContextualFoldingSetTrait<T, Ctx>::Equals(T &X, 388 const FoldingSetNodeID &ID, 389 unsigned /*IDHash*/, 390 FoldingSetNodeID &TempID, 391 Ctx Context) { 392 ContextualFoldingSetTrait<T, Ctx>::Profile(X, TempID, Context); 393 return TempID == ID; 394} 395template<typename T, typename Ctx> 396inline unsigned 397DefaultContextualFoldingSetTrait<T, Ctx>::ComputeHash(T &X, 398 FoldingSetNodeID &TempID, 399 Ctx Context) { 400 ContextualFoldingSetTrait<T, Ctx>::Profile(X, TempID, Context); 401 return TempID.ComputeHash(); 402} 403 404//===----------------------------------------------------------------------===// 405/// FoldingSet - This template class is used to instantiate a specialized 406/// implementation of the folding set to the node class T. T must be a 407/// subclass of FoldingSetNode and implement a Profile function. 408/// 409/// Note that this set type is movable and move-assignable. However, its 410/// moved-from state is not a valid state for anything other than 411/// move-assigning and destroying. This is primarily to enable movable APIs 412/// that incorporate these objects. 413template <class T> class FoldingSet final : public FoldingSetImpl { 414private: 415 /// GetNodeProfile - Each instantiatation of the FoldingSet needs to provide a 416 /// way to convert nodes into a unique specifier. 417 void GetNodeProfile(Node *N, FoldingSetNodeID &ID) const override { 418 T *TN = static_cast<T *>(N); 419 FoldingSetTrait<T>::Profile(*TN, ID); 420 } 421 /// NodeEquals - Instantiations may optionally provide a way to compare a 422 /// node with a specified ID. 423 bool NodeEquals(Node *N, const FoldingSetNodeID &ID, unsigned IDHash, 424 FoldingSetNodeID &TempID) const override { 425 T *TN = static_cast<T *>(N); 426 return FoldingSetTrait<T>::Equals(*TN, ID, IDHash, TempID); 427 } 428 /// ComputeNodeHash - Instantiations may optionally provide a way to compute a 429 /// hash value directly from a node. 430 unsigned ComputeNodeHash(Node *N, FoldingSetNodeID &TempID) const override { 431 T *TN = static_cast<T *>(N); 432 return FoldingSetTrait<T>::ComputeHash(*TN, TempID); 433 } 434 435public: 436 explicit FoldingSet(unsigned Log2InitSize = 6) 437 : FoldingSetImpl(Log2InitSize) {} 438 439 FoldingSet(FoldingSet &&Arg) : FoldingSetImpl(std::move(Arg)) {} 440 FoldingSet &operator=(FoldingSet &&RHS) { 441 (void)FoldingSetImpl::operator=(std::move(RHS)); 442 return *this; 443 } 444 445 typedef FoldingSetIterator<T> iterator; 446 iterator begin() { return iterator(Buckets); } 447 iterator end() { return iterator(Buckets+NumBuckets); } 448 449 typedef FoldingSetIterator<const T> const_iterator; 450 const_iterator begin() const { return const_iterator(Buckets); } 451 const_iterator end() const { return const_iterator(Buckets+NumBuckets); } 452 453 typedef FoldingSetBucketIterator<T> bucket_iterator; 454 455 bucket_iterator bucket_begin(unsigned hash) { 456 return bucket_iterator(Buckets + (hash & (NumBuckets-1))); 457 } 458 459 bucket_iterator bucket_end(unsigned hash) { 460 return bucket_iterator(Buckets + (hash & (NumBuckets-1)), true); 461 } 462 463 /// GetOrInsertNode - If there is an existing simple Node exactly 464 /// equal to the specified node, return it. Otherwise, insert 'N' and 465 /// return it instead. 466 T *GetOrInsertNode(Node *N) { 467 return static_cast<T *>(FoldingSetImpl::GetOrInsertNode(N)); 468 } 469 470 /// FindNodeOrInsertPos - Look up the node specified by ID. If it exists, 471 /// return it. If not, return the insertion token that will make insertion 472 /// faster. 473 T *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos) { 474 return static_cast<T *>(FoldingSetImpl::FindNodeOrInsertPos(ID, InsertPos)); 475 } 476}; 477 478//===----------------------------------------------------------------------===// 479/// ContextualFoldingSet - This template class is a further refinement 480/// of FoldingSet which provides a context argument when calling 481/// Profile on its nodes. Currently, that argument is fixed at 482/// initialization time. 483/// 484/// T must be a subclass of FoldingSetNode and implement a Profile 485/// function with signature 486/// void Profile(llvm::FoldingSetNodeID &, Ctx); 487template <class T, class Ctx> 488class ContextualFoldingSet final : public FoldingSetImpl { 489 // Unfortunately, this can't derive from FoldingSet<T> because the 490 // construction vtable for FoldingSet<T> requires 491 // FoldingSet<T>::GetNodeProfile to be instantiated, which in turn 492 // requires a single-argument T::Profile(). 493 494private: 495 Ctx Context; 496 497 /// GetNodeProfile - Each instantiatation of the FoldingSet needs to provide a 498 /// way to convert nodes into a unique specifier. 499 void GetNodeProfile(FoldingSetImpl::Node *N, 500 FoldingSetNodeID &ID) const override { 501 T *TN = static_cast<T *>(N); 502 ContextualFoldingSetTrait<T, Ctx>::Profile(*TN, ID, Context); 503 } 504 bool NodeEquals(FoldingSetImpl::Node *N, const FoldingSetNodeID &ID, 505 unsigned IDHash, FoldingSetNodeID &TempID) const override { 506 T *TN = static_cast<T *>(N); 507 return ContextualFoldingSetTrait<T, Ctx>::Equals(*TN, ID, IDHash, TempID, 508 Context); 509 } 510 unsigned ComputeNodeHash(FoldingSetImpl::Node *N, 511 FoldingSetNodeID &TempID) const override { 512 T *TN = static_cast<T *>(N); 513 return ContextualFoldingSetTrait<T, Ctx>::ComputeHash(*TN, TempID, Context); 514 } 515 516public: 517 explicit ContextualFoldingSet(Ctx Context, unsigned Log2InitSize = 6) 518 : FoldingSetImpl(Log2InitSize), Context(Context) 519 {} 520 521 Ctx getContext() const { return Context; } 522 523 typedef FoldingSetIterator<T> iterator; 524 iterator begin() { return iterator(Buckets); } 525 iterator end() { return iterator(Buckets+NumBuckets); } 526 527 typedef FoldingSetIterator<const T> const_iterator; 528 const_iterator begin() const { return const_iterator(Buckets); } 529 const_iterator end() const { return const_iterator(Buckets+NumBuckets); } 530 531 typedef FoldingSetBucketIterator<T> bucket_iterator; 532 533 bucket_iterator bucket_begin(unsigned hash) { 534 return bucket_iterator(Buckets + (hash & (NumBuckets-1))); 535 } 536 537 bucket_iterator bucket_end(unsigned hash) { 538 return bucket_iterator(Buckets + (hash & (NumBuckets-1)), true); 539 } 540 541 /// GetOrInsertNode - If there is an existing simple Node exactly 542 /// equal to the specified node, return it. Otherwise, insert 'N' 543 /// and return it instead. 544 T *GetOrInsertNode(Node *N) { 545 return static_cast<T *>(FoldingSetImpl::GetOrInsertNode(N)); 546 } 547 548 /// FindNodeOrInsertPos - Look up the node specified by ID. If it 549 /// exists, return it. If not, return the insertion token that will 550 /// make insertion faster. 551 T *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos) { 552 return static_cast<T *>(FoldingSetImpl::FindNodeOrInsertPos(ID, InsertPos)); 553 } 554}; 555 556//===----------------------------------------------------------------------===// 557/// FoldingSetVector - This template class combines a FoldingSet and a vector 558/// to provide the interface of FoldingSet but with deterministic iteration 559/// order based on the insertion order. T must be a subclass of FoldingSetNode 560/// and implement a Profile function. 561template <class T, class VectorT = SmallVector<T*, 8> > 562class FoldingSetVector { 563 FoldingSet<T> Set; 564 VectorT Vector; 565 566public: 567 explicit FoldingSetVector(unsigned Log2InitSize = 6) 568 : Set(Log2InitSize) { 569 } 570 571 typedef pointee_iterator<typename VectorT::iterator> iterator; 572 iterator begin() { return Vector.begin(); } 573 iterator end() { return Vector.end(); } 574 575 typedef pointee_iterator<typename VectorT::const_iterator> const_iterator; 576 const_iterator begin() const { return Vector.begin(); } 577 const_iterator end() const { return Vector.end(); } 578 579 /// clear - Remove all nodes from the folding set. 580 void clear() { Set.clear(); Vector.clear(); } 581 582 /// FindNodeOrInsertPos - Look up the node specified by ID. If it exists, 583 /// return it. If not, return the insertion token that will make insertion 584 /// faster. 585 T *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos) { 586 return Set.FindNodeOrInsertPos(ID, InsertPos); 587 } 588 589 /// GetOrInsertNode - If there is an existing simple Node exactly 590 /// equal to the specified node, return it. Otherwise, insert 'N' and 591 /// return it instead. 592 T *GetOrInsertNode(T *N) { 593 T *Result = Set.GetOrInsertNode(N); 594 if (Result == N) Vector.push_back(N); 595 return Result; 596 } 597 598 /// InsertNode - Insert the specified node into the folding set, knowing that 599 /// it is not already in the folding set. InsertPos must be obtained from 600 /// FindNodeOrInsertPos. 601 void InsertNode(T *N, void *InsertPos) { 602 Set.InsertNode(N, InsertPos); 603 Vector.push_back(N); 604 } 605 606 /// InsertNode - Insert the specified node into the folding set, knowing that 607 /// it is not already in the folding set. 608 void InsertNode(T *N) { 609 Set.InsertNode(N); 610 Vector.push_back(N); 611 } 612 613 /// size - Returns the number of nodes in the folding set. 614 unsigned size() const { return Set.size(); } 615 616 /// empty - Returns true if there are no nodes in the folding set. 617 bool empty() const { return Set.empty(); } 618}; 619 620//===----------------------------------------------------------------------===// 621/// FoldingSetIteratorImpl - This is the common iterator support shared by all 622/// folding sets, which knows how to walk the folding set hash table. 623class FoldingSetIteratorImpl { 624protected: 625 FoldingSetNode *NodePtr; 626 FoldingSetIteratorImpl(void **Bucket); 627 void advance(); 628 629public: 630 bool operator==(const FoldingSetIteratorImpl &RHS) const { 631 return NodePtr == RHS.NodePtr; 632 } 633 bool operator!=(const FoldingSetIteratorImpl &RHS) const { 634 return NodePtr != RHS.NodePtr; 635 } 636}; 637 638template <class T> class FoldingSetIterator : public FoldingSetIteratorImpl { 639public: 640 explicit FoldingSetIterator(void **Bucket) : FoldingSetIteratorImpl(Bucket) {} 641 642 T &operator*() const { 643 return *static_cast<T*>(NodePtr); 644 } 645 646 T *operator->() const { 647 return static_cast<T*>(NodePtr); 648 } 649 650 inline FoldingSetIterator &operator++() { // Preincrement 651 advance(); 652 return *this; 653 } 654 FoldingSetIterator operator++(int) { // Postincrement 655 FoldingSetIterator tmp = *this; ++*this; return tmp; 656 } 657}; 658 659//===----------------------------------------------------------------------===// 660/// FoldingSetBucketIteratorImpl - This is the common bucket iterator support 661/// shared by all folding sets, which knows how to walk a particular bucket 662/// of a folding set hash table. 663 664class FoldingSetBucketIteratorImpl { 665protected: 666 void *Ptr; 667 668 explicit FoldingSetBucketIteratorImpl(void **Bucket); 669 670 FoldingSetBucketIteratorImpl(void **Bucket, bool) 671 : Ptr(Bucket) {} 672 673 void advance() { 674 void *Probe = static_cast<FoldingSetNode*>(Ptr)->getNextInBucket(); 675 uintptr_t x = reinterpret_cast<uintptr_t>(Probe) & ~0x1; 676 Ptr = reinterpret_cast<void*>(x); 677 } 678 679public: 680 bool operator==(const FoldingSetBucketIteratorImpl &RHS) const { 681 return Ptr == RHS.Ptr; 682 } 683 bool operator!=(const FoldingSetBucketIteratorImpl &RHS) const { 684 return Ptr != RHS.Ptr; 685 } 686}; 687 688template <class T> 689class FoldingSetBucketIterator : public FoldingSetBucketIteratorImpl { 690public: 691 explicit FoldingSetBucketIterator(void **Bucket) : 692 FoldingSetBucketIteratorImpl(Bucket) {} 693 694 FoldingSetBucketIterator(void **Bucket, bool) : 695 FoldingSetBucketIteratorImpl(Bucket, true) {} 696 697 T &operator*() const { return *static_cast<T*>(Ptr); } 698 T *operator->() const { return static_cast<T*>(Ptr); } 699 700 inline FoldingSetBucketIterator &operator++() { // Preincrement 701 advance(); 702 return *this; 703 } 704 FoldingSetBucketIterator operator++(int) { // Postincrement 705 FoldingSetBucketIterator tmp = *this; ++*this; return tmp; 706 } 707}; 708 709//===----------------------------------------------------------------------===// 710/// FoldingSetNodeWrapper - This template class is used to "wrap" arbitrary 711/// types in an enclosing object so that they can be inserted into FoldingSets. 712template <typename T> 713class FoldingSetNodeWrapper : public FoldingSetNode { 714 T data; 715 716public: 717 template <typename... Ts> 718 explicit FoldingSetNodeWrapper(Ts &&... Args) 719 : data(std::forward<Ts>(Args)...) {} 720 721 void Profile(FoldingSetNodeID &ID) { FoldingSetTrait<T>::Profile(data, ID); } 722 723 T &getValue() { return data; } 724 const T &getValue() const { return data; } 725 726 operator T&() { return data; } 727 operator const T&() const { return data; } 728}; 729 730//===----------------------------------------------------------------------===// 731/// FastFoldingSetNode - This is a subclass of FoldingSetNode which stores 732/// a FoldingSetNodeID value rather than requiring the node to recompute it 733/// each time it is needed. This trades space for speed (which can be 734/// significant if the ID is long), and it also permits nodes to drop 735/// information that would otherwise only be required for recomputing an ID. 736class FastFoldingSetNode : public FoldingSetNode { 737 FoldingSetNodeID FastID; 738 739protected: 740 explicit FastFoldingSetNode(const FoldingSetNodeID &ID) : FastID(ID) {} 741 742public: 743 void Profile(FoldingSetNodeID &ID) const { ID.AddNodeID(FastID); } 744}; 745 746//===----------------------------------------------------------------------===// 747// Partial specializations of FoldingSetTrait. 748 749template<typename T> struct FoldingSetTrait<T*> { 750 static inline void Profile(T *X, FoldingSetNodeID &ID) { 751 ID.AddPointer(X); 752 } 753}; 754template <typename T1, typename T2> 755struct FoldingSetTrait<std::pair<T1, T2>> { 756 static inline void Profile(const std::pair<T1, T2> &P, 757 llvm::FoldingSetNodeID &ID) { 758 ID.Add(P.first); 759 ID.Add(P.second); 760 } 761}; 762} // End of namespace llvm. 763 764#endif 765