FoldingSet.h revision 0d651e0c9d47a459b91755ccf711119f5b085dc5
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/Support/DataTypes.h" 20#include "llvm/ADT/SmallVector.h" 21#include "llvm/ADT/StringRef.h" 22 23namespace llvm { 24 class APFloat; 25 class APInt; 26 class BumpPtrAllocator; 27 28/// This folding set used for two purposes: 29/// 1. Given information about a node we want to create, look up the unique 30/// instance of the node in the set. If the node already exists, return 31/// it, otherwise return the bucket it should be inserted into. 32/// 2. Given a node that has already been created, remove it from the set. 33/// 34/// This class is implemented as a single-link chained hash table, where the 35/// "buckets" are actually the nodes themselves (the next pointer is in the 36/// node). The last node points back to the bucket to simplify node removal. 37/// 38/// Any node that is to be included in the folding set must be a subclass of 39/// FoldingSetNode. The node class must also define a Profile method used to 40/// establish the unique bits of data for the node. The Profile method is 41/// passed a FoldingSetNodeID object which is used to gather the bits. Just 42/// call one of the Add* functions defined in the FoldingSetImpl::NodeID class. 43/// NOTE: That the folding set does not own the nodes and it is the 44/// responsibility of the user to dispose of the nodes. 45/// 46/// Eg. 47/// class MyNode : public FoldingSetNode { 48/// private: 49/// std::string Name; 50/// unsigned Value; 51/// public: 52/// MyNode(const char *N, unsigned V) : Name(N), Value(V) {} 53/// ... 54/// void Profile(FoldingSetNodeID &ID) const { 55/// ID.AddString(Name); 56/// ID.AddInteger(Value); 57/// } 58/// ... 59/// }; 60/// 61/// To define the folding set itself use the FoldingSet template; 62/// 63/// Eg. 64/// FoldingSet<MyNode> MyFoldingSet; 65/// 66/// Four public methods are available to manipulate the folding set; 67/// 68/// 1) If you have an existing node that you want add to the set but unsure 69/// that the node might already exist then call; 70/// 71/// MyNode *M = MyFoldingSet.GetOrInsertNode(N); 72/// 73/// If The result is equal to the input then the node has been inserted. 74/// Otherwise, the result is the node existing in the folding set, and the 75/// input can be discarded (use the result instead.) 76/// 77/// 2) If you are ready to construct a node but want to check if it already 78/// exists, then call FindNodeOrInsertPos with a FoldingSetNodeID of the bits to 79/// check; 80/// 81/// FoldingSetNodeID ID; 82/// ID.AddString(Name); 83/// ID.AddInteger(Value); 84/// void *InsertPoint; 85/// 86/// MyNode *M = MyFoldingSet.FindNodeOrInsertPos(ID, InsertPoint); 87/// 88/// If found then M with be non-NULL, else InsertPoint will point to where it 89/// should be inserted using InsertNode. 90/// 91/// 3) If you get a NULL result from FindNodeOrInsertPos then you can as a new 92/// node with FindNodeOrInsertPos; 93/// 94/// InsertNode(N, InsertPoint); 95/// 96/// 4) Finally, if you want to remove a node from the folding set call; 97/// 98/// bool WasRemoved = RemoveNode(N); 99/// 100/// The result indicates whether the node existed in the folding set. 101 102class FoldingSetNodeID; 103 104//===----------------------------------------------------------------------===// 105/// FoldingSetImpl - Implements the folding set functionality. The main 106/// structure is an array of buckets. Each bucket is indexed by the hash of 107/// the nodes it contains. The bucket itself points to the nodes contained 108/// in the bucket via a singly linked list. The last node in the list points 109/// back to the bucket to facilitate node removal. 110/// 111class FoldingSetImpl { 112protected: 113 /// Buckets - Array of bucket chains. 114 /// 115 void **Buckets; 116 117 /// NumBuckets - Length of the Buckets array. Always a power of 2. 118 /// 119 unsigned NumBuckets; 120 121 /// NumNodes - Number of nodes in the folding set. Growth occurs when NumNodes 122 /// is greater than twice the number of buckets. 123 unsigned NumNodes; 124 125public: 126 explicit FoldingSetImpl(unsigned Log2InitSize = 6); 127 virtual ~FoldingSetImpl(); 128 129 //===--------------------------------------------------------------------===// 130 /// Node - This class is used to maintain the singly linked bucket list in 131 /// a folding set. 132 /// 133 class Node { 134 private: 135 // NextInFoldingSetBucket - next link in the bucket list. 136 void *NextInFoldingSetBucket; 137 138 public: 139 140 Node() : NextInFoldingSetBucket(0) {} 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 183private: 184 185 /// GrowHashTable - Double the size of the hash table and rehash everything. 186 /// 187 void GrowHashTable(); 188 189protected: 190 191 /// GetNodeProfile - Instantiations of the FoldingSet template implement 192 /// this function to gather data bits for the given node. 193 virtual void GetNodeProfile(Node *N, FoldingSetNodeID &ID) const = 0; 194 /// NodeEquals - Instantiations of the FoldingSet template implement 195 /// this function to compare the given node with the given ID. 196 virtual bool NodeEquals(Node *N, const FoldingSetNodeID &ID, unsigned IDHash, 197 FoldingSetNodeID &TempID) const=0; 198 /// ComputeNodeHash - Instantiations of the FoldingSet template implement 199 /// this function to compute a hash value for the given node. 200 virtual unsigned ComputeNodeHash(Node *N, FoldingSetNodeID &TempID) const = 0; 201}; 202 203//===----------------------------------------------------------------------===// 204 205template<typename T> struct FoldingSetTrait; 206 207/// DefaultFoldingSetTrait - This class provides default implementations 208/// for FoldingSetTrait implementations. 209/// 210template<typename T> struct DefaultFoldingSetTrait { 211 static void Profile(const T &X, FoldingSetNodeID &ID) { 212 X.Profile(ID); 213 } 214 static void Profile(T &X, FoldingSetNodeID &ID) { 215 X.Profile(ID); 216 } 217 218 // Equals - Test if the profile for X would match ID, using TempID 219 // to compute a temporary ID if necessary. The default implementation 220 // just calls Profile and does a regular comparison. Implementations 221 // can override this to provide more efficient implementations. 222 static inline bool Equals(T &X, const FoldingSetNodeID &ID, unsigned IDHash, 223 FoldingSetNodeID &TempID); 224 225 // ComputeHash - Compute a hash value for X, using TempID to 226 // compute a temporary ID if necessary. The default implementation 227 // just calls Profile and does a regular hash computation. 228 // Implementations can override this to provide more efficient 229 // implementations. 230 static inline unsigned ComputeHash(T &X, FoldingSetNodeID &TempID); 231}; 232 233/// FoldingSetTrait - This trait class is used to define behavior of how 234/// to "profile" (in the FoldingSet parlance) an object of a given type. 235/// The default behavior is to invoke a 'Profile' method on an object, but 236/// through template specialization the behavior can be tailored for specific 237/// types. Combined with the FoldingSetNodeWrapper class, one can add objects 238/// to FoldingSets that were not originally designed to have that behavior. 239template<typename T> struct FoldingSetTrait 240 : public DefaultFoldingSetTrait<T> {}; 241 242template<typename T, typename Ctx> struct ContextualFoldingSetTrait; 243 244/// DefaultContextualFoldingSetTrait - Like DefaultFoldingSetTrait, but 245/// for ContextualFoldingSets. 246template<typename T, typename Ctx> 247struct DefaultContextualFoldingSetTrait { 248 static void Profile(T &X, FoldingSetNodeID &ID, Ctx Context) { 249 X.Profile(ID, Context); 250 } 251 static inline bool Equals(T &X, const FoldingSetNodeID &ID, unsigned IDHash, 252 FoldingSetNodeID &TempID, Ctx Context); 253 static inline unsigned ComputeHash(T &X, FoldingSetNodeID &TempID, 254 Ctx Context); 255}; 256 257/// ContextualFoldingSetTrait - Like FoldingSetTrait, but for 258/// ContextualFoldingSets. 259template<typename T, typename Ctx> struct ContextualFoldingSetTrait 260 : public DefaultContextualFoldingSetTrait<T, Ctx> {}; 261 262//===--------------------------------------------------------------------===// 263/// FoldingSetNodeIDRef - This class describes a reference to an interned 264/// FoldingSetNodeID, which can be a useful to store node id data rather 265/// than using plain FoldingSetNodeIDs, since the 32-element SmallVector 266/// is often much larger than necessary, and the possibility of heap 267/// allocation means it requires a non-trivial destructor call. 268class FoldingSetNodeIDRef { 269 const unsigned *Data; 270 size_t Size; 271public: 272 FoldingSetNodeIDRef() : Data(0), Size(0) {} 273 FoldingSetNodeIDRef(const unsigned *D, size_t S) : Data(D), Size(S) {} 274 275 /// ComputeHash - Compute a strong hash value for this FoldingSetNodeIDRef, 276 /// used to lookup the node in the FoldingSetImpl. 277 unsigned ComputeHash() const; 278 279 bool operator==(FoldingSetNodeIDRef) const; 280 281 /// Used to compare the "ordering" of two nodes as defined by the 282 /// profiled bits and their ordering defined by memcmp(). 283 bool operator<(FoldingSetNodeIDRef) const; 284 285 const unsigned *getData() const { return Data; } 286 size_t getSize() const { return Size; } 287}; 288 289//===--------------------------------------------------------------------===// 290/// FoldingSetNodeID - This class is used to gather all the unique data bits of 291/// a node. When all the bits are gathered this class is used to produce a 292/// hash value for the node. 293/// 294class FoldingSetNodeID { 295 /// Bits - Vector of all the data bits that make the node unique. 296 /// Use a SmallVector to avoid a heap allocation in the common case. 297 SmallVector<unsigned, 32> Bits; 298 299public: 300 FoldingSetNodeID() {} 301 302 FoldingSetNodeID(FoldingSetNodeIDRef Ref) 303 : Bits(Ref.getData(), Ref.getData() + Ref.getSize()) {} 304 305 /// Add* - Add various data types to Bit data. 306 /// 307 void AddPointer(const void *Ptr); 308 void AddInteger(signed I); 309 void AddInteger(unsigned I); 310 void AddInteger(long I); 311 void AddInteger(unsigned long I); 312 void AddInteger(long long I); 313 void AddInteger(unsigned long long I); 314 void AddBoolean(bool B) { AddInteger(B ? 1U : 0U); } 315 void AddString(StringRef String); 316 void AddNodeID(const FoldingSetNodeID &ID); 317 318 template <typename T> 319 inline void Add(const T &x) { FoldingSetTrait<T>::Profile(x, *this); } 320 321 /// clear - Clear the accumulated profile, allowing this FoldingSetNodeID 322 /// object to be used to compute a new profile. 323 inline void clear() { Bits.clear(); } 324 325 /// ComputeHash - Compute a strong hash value for this FoldingSetNodeID, used 326 /// to lookup the node in the FoldingSetImpl. 327 unsigned ComputeHash() const; 328 329 /// operator== - Used to compare two nodes to each other. 330 /// 331 bool operator==(const FoldingSetNodeID &RHS) const; 332 bool operator==(const FoldingSetNodeIDRef RHS) const; 333 334 /// Used to compare the "ordering" of two nodes as defined by the 335 /// profiled bits and their ordering defined by memcmp(). 336 bool operator<(const FoldingSetNodeID &RHS) const; 337 bool operator<(const FoldingSetNodeIDRef RHS) const; 338 339 /// Intern - Copy this node's data to a memory region allocated from the 340 /// given allocator and return a FoldingSetNodeIDRef describing the 341 /// interned data. 342 FoldingSetNodeIDRef Intern(BumpPtrAllocator &Allocator) const; 343}; 344 345// Convenience type to hide the implementation of the folding set. 346typedef FoldingSetImpl::Node FoldingSetNode; 347template<class T> class FoldingSetIterator; 348template<class T> class FoldingSetBucketIterator; 349 350// Definitions of FoldingSetTrait and ContextualFoldingSetTrait functions, which 351// require the definition of FoldingSetNodeID. 352template<typename T> 353inline bool 354DefaultFoldingSetTrait<T>::Equals(T &X, const FoldingSetNodeID &ID, 355 unsigned IDHash, FoldingSetNodeID &TempID) { 356 FoldingSetTrait<T>::Profile(X, TempID); 357 return TempID == ID; 358} 359template<typename T> 360inline unsigned 361DefaultFoldingSetTrait<T>::ComputeHash(T &X, FoldingSetNodeID &TempID) { 362 FoldingSetTrait<T>::Profile(X, TempID); 363 return TempID.ComputeHash(); 364} 365template<typename T, typename Ctx> 366inline bool 367DefaultContextualFoldingSetTrait<T, Ctx>::Equals(T &X, 368 const FoldingSetNodeID &ID, 369 unsigned IDHash, 370 FoldingSetNodeID &TempID, 371 Ctx Context) { 372 ContextualFoldingSetTrait<T, Ctx>::Profile(X, TempID, Context); 373 return TempID == ID; 374} 375template<typename T, typename Ctx> 376inline unsigned 377DefaultContextualFoldingSetTrait<T, Ctx>::ComputeHash(T &X, 378 FoldingSetNodeID &TempID, 379 Ctx Context) { 380 ContextualFoldingSetTrait<T, Ctx>::Profile(X, TempID, Context); 381 return TempID.ComputeHash(); 382} 383 384//===----------------------------------------------------------------------===// 385/// FoldingSet - This template class is used to instantiate a specialized 386/// implementation of the folding set to the node class T. T must be a 387/// subclass of FoldingSetNode and implement a Profile function. 388/// 389template<class T> class FoldingSet : public FoldingSetImpl { 390private: 391 /// GetNodeProfile - Each instantiatation of the FoldingSet needs to provide a 392 /// way to convert nodes into a unique specifier. 393 virtual void GetNodeProfile(Node *N, FoldingSetNodeID &ID) const { 394 T *TN = static_cast<T *>(N); 395 FoldingSetTrait<T>::Profile(*TN, ID); 396 } 397 /// NodeEquals - Instantiations may optionally provide a way to compare a 398 /// node with a specified ID. 399 virtual bool NodeEquals(Node *N, const FoldingSetNodeID &ID, unsigned IDHash, 400 FoldingSetNodeID &TempID) const { 401 T *TN = static_cast<T *>(N); 402 return FoldingSetTrait<T>::Equals(*TN, ID, IDHash, TempID); 403 } 404 /// ComputeNodeHash - Instantiations may optionally provide a way to compute a 405 /// hash value directly from a node. 406 virtual unsigned ComputeNodeHash(Node *N, FoldingSetNodeID &TempID) const { 407 T *TN = static_cast<T *>(N); 408 return FoldingSetTrait<T>::ComputeHash(*TN, TempID); 409 } 410 411public: 412 explicit FoldingSet(unsigned Log2InitSize = 6) 413 : FoldingSetImpl(Log2InitSize) 414 {} 415 416 typedef FoldingSetIterator<T> iterator; 417 iterator begin() { return iterator(Buckets); } 418 iterator end() { return iterator(Buckets+NumBuckets); } 419 420 typedef FoldingSetIterator<const T> const_iterator; 421 const_iterator begin() const { return const_iterator(Buckets); } 422 const_iterator end() const { return const_iterator(Buckets+NumBuckets); } 423 424 typedef FoldingSetBucketIterator<T> bucket_iterator; 425 426 bucket_iterator bucket_begin(unsigned hash) { 427 return bucket_iterator(Buckets + (hash & (NumBuckets-1))); 428 } 429 430 bucket_iterator bucket_end(unsigned hash) { 431 return bucket_iterator(Buckets + (hash & (NumBuckets-1)), true); 432 } 433 434 /// GetOrInsertNode - If there is an existing simple Node exactly 435 /// equal to the specified node, return it. Otherwise, insert 'N' and 436 /// return it instead. 437 T *GetOrInsertNode(Node *N) { 438 return static_cast<T *>(FoldingSetImpl::GetOrInsertNode(N)); 439 } 440 441 /// FindNodeOrInsertPos - Look up the node specified by ID. If it exists, 442 /// return it. If not, return the insertion token that will make insertion 443 /// faster. 444 T *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos) { 445 return static_cast<T *>(FoldingSetImpl::FindNodeOrInsertPos(ID, InsertPos)); 446 } 447}; 448 449//===----------------------------------------------------------------------===// 450/// ContextualFoldingSet - This template class is a further refinement 451/// of FoldingSet which provides a context argument when calling 452/// Profile on its nodes. Currently, that argument is fixed at 453/// initialization time. 454/// 455/// T must be a subclass of FoldingSetNode and implement a Profile 456/// function with signature 457/// void Profile(llvm::FoldingSetNodeID &, Ctx); 458template <class T, class Ctx> 459class ContextualFoldingSet : public FoldingSetImpl { 460 // Unfortunately, this can't derive from FoldingSet<T> because the 461 // construction vtable for FoldingSet<T> requires 462 // FoldingSet<T>::GetNodeProfile to be instantiated, which in turn 463 // requires a single-argument T::Profile(). 464 465private: 466 Ctx Context; 467 468 /// GetNodeProfile - Each instantiatation of the FoldingSet needs to provide a 469 /// way to convert nodes into a unique specifier. 470 virtual void GetNodeProfile(FoldingSetImpl::Node *N, 471 FoldingSetNodeID &ID) const { 472 T *TN = static_cast<T *>(N); 473 ContextualFoldingSetTrait<T, Ctx>::Profile(*TN, ID, Context); 474 } 475 virtual bool NodeEquals(FoldingSetImpl::Node *N, 476 const FoldingSetNodeID &ID, unsigned IDHash, 477 FoldingSetNodeID &TempID) const { 478 T *TN = static_cast<T *>(N); 479 return ContextualFoldingSetTrait<T, Ctx>::Equals(*TN, ID, IDHash, TempID, 480 Context); 481 } 482 virtual unsigned ComputeNodeHash(FoldingSetImpl::Node *N, 483 FoldingSetNodeID &TempID) const { 484 T *TN = static_cast<T *>(N); 485 return ContextualFoldingSetTrait<T, Ctx>::ComputeHash(*TN, TempID, Context); 486 } 487 488public: 489 explicit ContextualFoldingSet(Ctx Context, unsigned Log2InitSize = 6) 490 : FoldingSetImpl(Log2InitSize), Context(Context) 491 {} 492 493 Ctx getContext() const { return Context; } 494 495 496 typedef FoldingSetIterator<T> iterator; 497 iterator begin() { return iterator(Buckets); } 498 iterator end() { return iterator(Buckets+NumBuckets); } 499 500 typedef FoldingSetIterator<const T> const_iterator; 501 const_iterator begin() const { return const_iterator(Buckets); } 502 const_iterator end() const { return const_iterator(Buckets+NumBuckets); } 503 504 typedef FoldingSetBucketIterator<T> bucket_iterator; 505 506 bucket_iterator bucket_begin(unsigned hash) { 507 return bucket_iterator(Buckets + (hash & (NumBuckets-1))); 508 } 509 510 bucket_iterator bucket_end(unsigned hash) { 511 return bucket_iterator(Buckets + (hash & (NumBuckets-1)), true); 512 } 513 514 /// GetOrInsertNode - If there is an existing simple Node exactly 515 /// equal to the specified node, return it. Otherwise, insert 'N' 516 /// and return it instead. 517 T *GetOrInsertNode(Node *N) { 518 return static_cast<T *>(FoldingSetImpl::GetOrInsertNode(N)); 519 } 520 521 /// FindNodeOrInsertPos - Look up the node specified by ID. If it 522 /// exists, return it. If not, return the insertion token that will 523 /// make insertion faster. 524 T *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos) { 525 return static_cast<T *>(FoldingSetImpl::FindNodeOrInsertPos(ID, InsertPos)); 526 } 527}; 528 529//===----------------------------------------------------------------------===// 530/// FoldingSetVectorIterator - This implements an iterator for 531/// FoldingSetVector. It is only necessary because FoldingSetIterator provides 532/// a value_type of T, while the vector in FoldingSetVector exposes 533/// a value_type of T*. Fortunately, FoldingSetIterator doesn't expose very 534/// much besides operator* and operator->, so we just wrap the inner vector 535/// iterator and perform the extra dereference. 536template <class T, class VectorIteratorT> 537class FoldingSetVectorIterator { 538 // Provide a typedef to workaround the lack of correct injected class name 539 // support in older GCCs. 540 typedef FoldingSetVectorIterator<T, VectorIteratorT> SelfT; 541 542 VectorIteratorT Iterator; 543 544public: 545 FoldingSetVectorIterator(VectorIteratorT I) : Iterator(I) {} 546 547 bool operator==(const SelfT &RHS) const { 548 return Iterator == RHS.Iterator; 549 } 550 bool operator!=(const SelfT &RHS) const { 551 return Iterator != RHS.Iterator; 552 } 553 554 T &operator*() const { return **Iterator; } 555 556 T *operator->() const { return *Iterator; } 557 558 inline SelfT &operator++() { 559 ++Iterator; 560 return *this; 561 } 562 SelfT operator++(int) { 563 SelfT tmp = *this; 564 ++*this; 565 return tmp; 566 } 567}; 568 569//===----------------------------------------------------------------------===// 570/// FoldingSetVector - This template class combines a FoldingSet and a vector 571/// to provide the interface of FoldingSet but with deterministic iteration 572/// order based on the insertion order. T must be a subclass of FoldingSetNode 573/// and implement a Profile function. 574template <class T, class VectorT = SmallVector<T*, 8> > 575class FoldingSetVector { 576 FoldingSet<T> Set; 577 VectorT Vector; 578 579public: 580 explicit FoldingSetVector(unsigned Log2InitSize = 6) 581 : Set(Log2InitSize) { 582 } 583 584 typedef FoldingSetVectorIterator<T, typename VectorT::iterator> iterator; 585 iterator begin() { return Vector.begin(); } 586 iterator end() { return Vector.end(); } 587 588 typedef FoldingSetVectorIterator<const T, typename VectorT::const_iterator> 589 const_iterator; 590 const_iterator begin() const { return Vector.begin(); } 591 const_iterator end() const { return Vector.end(); } 592 593 /// clear - Remove all nodes from the folding set. 594 void clear() { Set.clear(); Vector.clear(); } 595 596 /// FindNodeOrInsertPos - Look up the node specified by ID. If it exists, 597 /// return it. If not, return the insertion token that will make insertion 598 /// faster. 599 T *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos) { 600 return Set.FindNodeOrInsertPos(ID, InsertPos); 601 } 602 603 /// GetOrInsertNode - If there is an existing simple Node exactly 604 /// equal to the specified node, return it. Otherwise, insert 'N' and 605 /// return it instead. 606 T *GetOrInsertNode(T *N) { 607 T *Result = Set.GetOrInsertNode(N); 608 if (Result == N) Vector.push_back(N); 609 return Result; 610 } 611 612 /// InsertNode - Insert the specified node into the folding set, knowing that 613 /// it is not already in the folding set. InsertPos must be obtained from 614 /// FindNodeOrInsertPos. 615 void InsertNode(T *N, void *InsertPos) { 616 Set.InsertNode(N, InsertPos); 617 Vector.push_back(N); 618 } 619 620 /// InsertNode - Insert the specified node into the folding set, knowing that 621 /// it is not already in the folding set. 622 void InsertNode(T *N) { 623 Set.InsertNode(N); 624 Vector.push_back(N); 625 } 626 627 /// size - Returns the number of nodes in the folding set. 628 unsigned size() const { return Set.size(); } 629 630 /// empty - Returns true if there are no nodes in the folding set. 631 bool empty() const { return Set.empty(); } 632}; 633 634//===----------------------------------------------------------------------===// 635/// FoldingSetIteratorImpl - This is the common iterator support shared by all 636/// folding sets, which knows how to walk the folding set hash table. 637class FoldingSetIteratorImpl { 638protected: 639 FoldingSetNode *NodePtr; 640 FoldingSetIteratorImpl(void **Bucket); 641 void advance(); 642 643public: 644 bool operator==(const FoldingSetIteratorImpl &RHS) const { 645 return NodePtr == RHS.NodePtr; 646 } 647 bool operator!=(const FoldingSetIteratorImpl &RHS) const { 648 return NodePtr != RHS.NodePtr; 649 } 650}; 651 652 653template<class T> 654class FoldingSetIterator : public FoldingSetIteratorImpl { 655public: 656 explicit FoldingSetIterator(void **Bucket) : FoldingSetIteratorImpl(Bucket) {} 657 658 T &operator*() const { 659 return *static_cast<T*>(NodePtr); 660 } 661 662 T *operator->() const { 663 return static_cast<T*>(NodePtr); 664 } 665 666 inline FoldingSetIterator &operator++() { // Preincrement 667 advance(); 668 return *this; 669 } 670 FoldingSetIterator operator++(int) { // Postincrement 671 FoldingSetIterator tmp = *this; ++*this; return tmp; 672 } 673}; 674 675//===----------------------------------------------------------------------===// 676/// FoldingSetBucketIteratorImpl - This is the common bucket iterator support 677/// shared by all folding sets, which knows how to walk a particular bucket 678/// of a folding set hash table. 679 680class FoldingSetBucketIteratorImpl { 681protected: 682 void *Ptr; 683 684 explicit FoldingSetBucketIteratorImpl(void **Bucket); 685 686 FoldingSetBucketIteratorImpl(void **Bucket, bool) 687 : Ptr(Bucket) {} 688 689 void advance() { 690 void *Probe = static_cast<FoldingSetNode*>(Ptr)->getNextInBucket(); 691 uintptr_t x = reinterpret_cast<uintptr_t>(Probe) & ~0x1; 692 Ptr = reinterpret_cast<void*>(x); 693 } 694 695public: 696 bool operator==(const FoldingSetBucketIteratorImpl &RHS) const { 697 return Ptr == RHS.Ptr; 698 } 699 bool operator!=(const FoldingSetBucketIteratorImpl &RHS) const { 700 return Ptr != RHS.Ptr; 701 } 702}; 703 704 705template<class T> 706class FoldingSetBucketIterator : public FoldingSetBucketIteratorImpl { 707public: 708 explicit FoldingSetBucketIterator(void **Bucket) : 709 FoldingSetBucketIteratorImpl(Bucket) {} 710 711 FoldingSetBucketIterator(void **Bucket, bool) : 712 FoldingSetBucketIteratorImpl(Bucket, true) {} 713 714 T &operator*() const { return *static_cast<T*>(Ptr); } 715 T *operator->() const { return static_cast<T*>(Ptr); } 716 717 inline FoldingSetBucketIterator &operator++() { // Preincrement 718 advance(); 719 return *this; 720 } 721 FoldingSetBucketIterator operator++(int) { // Postincrement 722 FoldingSetBucketIterator tmp = *this; ++*this; return tmp; 723 } 724}; 725 726//===----------------------------------------------------------------------===// 727/// FoldingSetNodeWrapper - This template class is used to "wrap" arbitrary 728/// types in an enclosing object so that they can be inserted into FoldingSets. 729template <typename T> 730class FoldingSetNodeWrapper : public FoldingSetNode { 731 T data; 732public: 733 explicit FoldingSetNodeWrapper(const T &x) : data(x) {} 734 virtual ~FoldingSetNodeWrapper() {} 735 736 template<typename A1> 737 explicit FoldingSetNodeWrapper(const A1 &a1) 738 : data(a1) {} 739 740 template <typename A1, typename A2> 741 explicit FoldingSetNodeWrapper(const A1 &a1, const A2 &a2) 742 : data(a1,a2) {} 743 744 template <typename A1, typename A2, typename A3> 745 explicit FoldingSetNodeWrapper(const A1 &a1, const A2 &a2, const A3 &a3) 746 : data(a1,a2,a3) {} 747 748 template <typename A1, typename A2, typename A3, typename A4> 749 explicit FoldingSetNodeWrapper(const A1 &a1, const A2 &a2, const A3 &a3, 750 const A4 &a4) 751 : data(a1,a2,a3,a4) {} 752 753 template <typename A1, typename A2, typename A3, typename A4, typename A5> 754 explicit FoldingSetNodeWrapper(const A1 &a1, const A2 &a2, const A3 &a3, 755 const A4 &a4, const A5 &a5) 756 : data(a1,a2,a3,a4,a5) {} 757 758 759 void Profile(FoldingSetNodeID &ID) { FoldingSetTrait<T>::Profile(data, ID); } 760 761 T &getValue() { return data; } 762 const T &getValue() const { return data; } 763 764 operator T&() { return data; } 765 operator const T&() const { return data; } 766}; 767 768//===----------------------------------------------------------------------===// 769/// FastFoldingSetNode - This is a subclass of FoldingSetNode which stores 770/// a FoldingSetNodeID value rather than requiring the node to recompute it 771/// each time it is needed. This trades space for speed (which can be 772/// significant if the ID is long), and it also permits nodes to drop 773/// information that would otherwise only be required for recomputing an ID. 774class FastFoldingSetNode : public FoldingSetNode { 775 FoldingSetNodeID FastID; 776protected: 777 explicit FastFoldingSetNode(const FoldingSetNodeID &ID) : FastID(ID) {} 778public: 779 void Profile(FoldingSetNodeID &ID) const { 780 ID.AddNodeID(FastID); 781 } 782}; 783 784//===----------------------------------------------------------------------===// 785// Partial specializations of FoldingSetTrait. 786 787template<typename T> struct FoldingSetTrait<T*> { 788 static inline void Profile(T *X, FoldingSetNodeID &ID) { 789 ID.AddPointer(X); 790 } 791}; 792} // End of namespace llvm. 793 794#endif 795