1 //===-- llvm/ADT/FoldingSet.h - Uniquing Hash Set ---------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
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.
14 //===----------------------------------------------------------------------===//
16 #ifndef LLVM_ADT_FOLDINGSET_H
17 #define LLVM_ADT_FOLDINGSET_H
19 #include "llvm/ADT/SmallVector.h"
20 #include "llvm/ADT/StringRef.h"
21 #include "llvm/Support/DataTypes.h"
26 class BumpPtrAllocator;
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.
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.
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.
47 /// class MyNode : public FoldingSetNode {
52 /// MyNode(const char *N, unsigned V) : Name(N), Value(V) {}
54 /// void Profile(FoldingSetNodeID &ID) const {
55 /// ID.AddString(Name);
56 /// ID.AddInteger(Value);
61 /// To define the folding set itself use the FoldingSet template;
64 /// FoldingSet<MyNode> MyFoldingSet;
66 /// Four public methods are available to manipulate the folding set;
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;
71 /// MyNode *M = MyFoldingSet.GetOrInsertNode(N);
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.)
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
81 /// FoldingSetNodeID ID;
82 /// ID.AddString(Name);
83 /// ID.AddInteger(Value);
84 /// void *InsertPoint;
86 /// MyNode *M = MyFoldingSet.FindNodeOrInsertPos(ID, InsertPoint);
88 /// If found then M with be non-NULL, else InsertPoint will point to where it
89 /// should be inserted using InsertNode.
91 /// 3) If you get a NULL result from FindNodeOrInsertPos then you can as a new
92 /// node with FindNodeOrInsertPos;
94 /// InsertNode(N, InsertPoint);
96 /// 4) Finally, if you want to remove a node from the folding set call;
98 /// bool WasRemoved = RemoveNode(N);
100 /// The result indicates whether the node existed in the folding set.
102 class FoldingSetNodeID;
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.
111 class FoldingSetImpl {
113 /// Buckets - Array of bucket chains.
117 /// NumBuckets - Length of the Buckets array. Always a power of 2.
121 /// NumNodes - Number of nodes in the folding set. Growth occurs when NumNodes
122 /// is greater than twice the number of buckets.
126 explicit FoldingSetImpl(unsigned Log2InitSize = 6);
127 virtual ~FoldingSetImpl();
129 //===--------------------------------------------------------------------===//
130 /// Node - This class is used to maintain the singly linked bucket list in
135 // NextInFoldingSetBucket - next link in the bucket list.
136 void *NextInFoldingSetBucket;
140 Node() : NextInFoldingSetBucket(0) {}
143 void *getNextInBucket() const { return NextInFoldingSetBucket; }
144 void SetNextInBucket(void *N) { NextInFoldingSetBucket = N; }
147 /// clear - Remove all nodes from the folding set.
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);
154 /// GetOrInsertNode - If there is an existing simple Node exactly
155 /// equal to the specified node, return it. Otherwise, insert 'N' and return
157 Node *GetOrInsertNode(Node *N);
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
162 Node *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos);
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);
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);
174 assert(Inserted == N && "Node already inserted!");
177 /// size - Returns the number of nodes in the folding set.
178 unsigned size() const { return NumNodes; }
180 /// empty - Returns true if there are no nodes in the folding set.
181 bool empty() const { return NumNodes == 0; }
185 /// GrowHashTable - Double the size of the hash table and rehash everything.
187 void GrowHashTable();
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;
203 //===----------------------------------------------------------------------===//
205 template<typename T> struct FoldingSetTrait;
207 /// DefaultFoldingSetTrait - This class provides default implementations
208 /// for FoldingSetTrait implementations.
210 template<typename T> struct DefaultFoldingSetTrait {
211 static void Profile(const T &X, FoldingSetNodeID &ID) {
214 static void Profile(T &X, FoldingSetNodeID &ID) {
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);
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
230 static inline unsigned ComputeHash(T &X, FoldingSetNodeID &TempID);
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.
239 template<typename T> struct FoldingSetTrait
240 : public DefaultFoldingSetTrait<T> {};
242 template<typename T, typename Ctx> struct ContextualFoldingSetTrait;
244 /// DefaultContextualFoldingSetTrait - Like DefaultFoldingSetTrait, but
245 /// for ContextualFoldingSets.
246 template<typename T, typename Ctx>
247 struct DefaultContextualFoldingSetTrait {
248 static void Profile(T &X, FoldingSetNodeID &ID, Ctx Context) {
249 X.Profile(ID, Context);
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,
257 /// ContextualFoldingSetTrait - Like FoldingSetTrait, but for
258 /// ContextualFoldingSets.
259 template<typename T, typename Ctx> struct ContextualFoldingSetTrait
260 : public DefaultContextualFoldingSetTrait<T, Ctx> {};
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.
268 class FoldingSetNodeIDRef {
269 const unsigned *Data;
272 FoldingSetNodeIDRef() : Data(0), Size(0) {}
273 FoldingSetNodeIDRef(const unsigned *D, size_t S) : Data(D), Size(S) {}
275 /// ComputeHash - Compute a strong hash value for this FoldingSetNodeIDRef,
276 /// used to lookup the node in the FoldingSetImpl.
277 unsigned ComputeHash() const;
279 bool operator==(FoldingSetNodeIDRef) const;
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;
285 const unsigned *getData() const { return Data; }
286 size_t getSize() const { return Size; }
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.
294 class 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;
300 FoldingSetNodeID() {}
302 FoldingSetNodeID(FoldingSetNodeIDRef Ref)
303 : Bits(Ref.getData(), Ref.getData() + Ref.getSize()) {}
305 /// Add* - Add various data types to Bit data.
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);
318 template <typename T>
319 inline void Add(const T &x) { FoldingSetTrait<T>::Profile(x, *this); }
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(); }
325 /// ComputeHash - Compute a strong hash value for this FoldingSetNodeID, used
326 /// to lookup the node in the FoldingSetImpl.
327 unsigned ComputeHash() const;
329 /// operator== - Used to compare two nodes to each other.
331 bool operator==(const FoldingSetNodeID &RHS) const;
332 bool operator==(const FoldingSetNodeIDRef RHS) const;
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;
339 /// Intern - Copy this node's data to a memory region allocated from the
340 /// given allocator and return a FoldingSetNodeIDRef describing the
342 FoldingSetNodeIDRef Intern(BumpPtrAllocator &Allocator) const;
345 // Convenience type to hide the implementation of the folding set.
346 typedef FoldingSetImpl::Node FoldingSetNode;
347 template<class T> class FoldingSetIterator;
348 template<class T> class FoldingSetBucketIterator;
350 // Definitions of FoldingSetTrait and ContextualFoldingSetTrait functions, which
351 // require the definition of FoldingSetNodeID.
354 DefaultFoldingSetTrait<T>::Equals(T &X, const FoldingSetNodeID &ID,
356 FoldingSetNodeID &TempID) {
357 FoldingSetTrait<T>::Profile(X, TempID);
362 DefaultFoldingSetTrait<T>::ComputeHash(T &X, FoldingSetNodeID &TempID) {
363 FoldingSetTrait<T>::Profile(X, TempID);
364 return TempID.ComputeHash();
366 template<typename T, typename Ctx>
368 DefaultContextualFoldingSetTrait<T, Ctx>::Equals(T &X,
369 const FoldingSetNodeID &ID,
371 FoldingSetNodeID &TempID,
373 ContextualFoldingSetTrait<T, Ctx>::Profile(X, TempID, Context);
376 template<typename T, typename Ctx>
378 DefaultContextualFoldingSetTrait<T, Ctx>::ComputeHash(T &X,
379 FoldingSetNodeID &TempID,
381 ContextualFoldingSetTrait<T, Ctx>::Profile(X, TempID, Context);
382 return TempID.ComputeHash();
385 //===----------------------------------------------------------------------===//
386 /// FoldingSet - This template class is used to instantiate a specialized
387 /// implementation of the folding set to the node class T. T must be a
388 /// subclass of FoldingSetNode and implement a Profile function.
390 template<class T> class FoldingSet : public FoldingSetImpl {
392 /// GetNodeProfile - Each instantiatation of the FoldingSet needs to provide a
393 /// way to convert nodes into a unique specifier.
394 virtual void GetNodeProfile(Node *N, FoldingSetNodeID &ID) const {
395 T *TN = static_cast<T *>(N);
396 FoldingSetTrait<T>::Profile(*TN, ID);
398 /// NodeEquals - Instantiations may optionally provide a way to compare a
399 /// node with a specified ID.
400 virtual bool NodeEquals(Node *N, const FoldingSetNodeID &ID, unsigned IDHash,
401 FoldingSetNodeID &TempID) const {
402 T *TN = static_cast<T *>(N);
403 return FoldingSetTrait<T>::Equals(*TN, ID, IDHash, TempID);
405 /// ComputeNodeHash - Instantiations may optionally provide a way to compute a
406 /// hash value directly from a node.
407 virtual unsigned ComputeNodeHash(Node *N, FoldingSetNodeID &TempID) const {
408 T *TN = static_cast<T *>(N);
409 return FoldingSetTrait<T>::ComputeHash(*TN, TempID);
413 explicit FoldingSet(unsigned Log2InitSize = 6)
414 : FoldingSetImpl(Log2InitSize)
417 typedef FoldingSetIterator<T> iterator;
418 iterator begin() { return iterator(Buckets); }
419 iterator end() { return iterator(Buckets+NumBuckets); }
421 typedef FoldingSetIterator<const T> const_iterator;
422 const_iterator begin() const { return const_iterator(Buckets); }
423 const_iterator end() const { return const_iterator(Buckets+NumBuckets); }
425 typedef FoldingSetBucketIterator<T> bucket_iterator;
427 bucket_iterator bucket_begin(unsigned hash) {
428 return bucket_iterator(Buckets + (hash & (NumBuckets-1)));
431 bucket_iterator bucket_end(unsigned hash) {
432 return bucket_iterator(Buckets + (hash & (NumBuckets-1)), true);
435 /// GetOrInsertNode - If there is an existing simple Node exactly
436 /// equal to the specified node, return it. Otherwise, insert 'N' and
437 /// return it instead.
438 T *GetOrInsertNode(Node *N) {
439 return static_cast<T *>(FoldingSetImpl::GetOrInsertNode(N));
442 /// FindNodeOrInsertPos - Look up the node specified by ID. If it exists,
443 /// return it. If not, return the insertion token that will make insertion
445 T *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos) {
446 return static_cast<T *>(FoldingSetImpl::FindNodeOrInsertPos(ID, InsertPos));
450 //===----------------------------------------------------------------------===//
451 /// ContextualFoldingSet - This template class is a further refinement
452 /// of FoldingSet which provides a context argument when calling
453 /// Profile on its nodes. Currently, that argument is fixed at
454 /// initialization time.
456 /// T must be a subclass of FoldingSetNode and implement a Profile
457 /// function with signature
458 /// void Profile(llvm::FoldingSetNodeID &, Ctx);
459 template <class T, class Ctx>
460 class ContextualFoldingSet : public FoldingSetImpl {
461 // Unfortunately, this can't derive from FoldingSet<T> because the
462 // construction vtable for FoldingSet<T> requires
463 // FoldingSet<T>::GetNodeProfile to be instantiated, which in turn
464 // requires a single-argument T::Profile().
469 /// GetNodeProfile - Each instantiatation of the FoldingSet needs to provide a
470 /// way to convert nodes into a unique specifier.
471 virtual void GetNodeProfile(FoldingSetImpl::Node *N,
472 FoldingSetNodeID &ID) const {
473 T *TN = static_cast<T *>(N);
474 ContextualFoldingSetTrait<T, Ctx>::Profile(*TN, ID, Context);
476 virtual bool NodeEquals(FoldingSetImpl::Node *N,
477 const FoldingSetNodeID &ID, unsigned IDHash,
478 FoldingSetNodeID &TempID) const {
479 T *TN = static_cast<T *>(N);
480 return ContextualFoldingSetTrait<T, Ctx>::Equals(*TN, ID, IDHash, TempID,
483 virtual unsigned ComputeNodeHash(FoldingSetImpl::Node *N,
484 FoldingSetNodeID &TempID) const {
485 T *TN = static_cast<T *>(N);
486 return ContextualFoldingSetTrait<T, Ctx>::ComputeHash(*TN, TempID, Context);
490 explicit ContextualFoldingSet(Ctx Context, unsigned Log2InitSize = 6)
491 : FoldingSetImpl(Log2InitSize), Context(Context)
494 Ctx getContext() const { return Context; }
497 typedef FoldingSetIterator<T> iterator;
498 iterator begin() { return iterator(Buckets); }
499 iterator end() { return iterator(Buckets+NumBuckets); }
501 typedef FoldingSetIterator<const T> const_iterator;
502 const_iterator begin() const { return const_iterator(Buckets); }
503 const_iterator end() const { return const_iterator(Buckets+NumBuckets); }
505 typedef FoldingSetBucketIterator<T> bucket_iterator;
507 bucket_iterator bucket_begin(unsigned hash) {
508 return bucket_iterator(Buckets + (hash & (NumBuckets-1)));
511 bucket_iterator bucket_end(unsigned hash) {
512 return bucket_iterator(Buckets + (hash & (NumBuckets-1)), true);
515 /// GetOrInsertNode - If there is an existing simple Node exactly
516 /// equal to the specified node, return it. Otherwise, insert 'N'
517 /// and return it instead.
518 T *GetOrInsertNode(Node *N) {
519 return static_cast<T *>(FoldingSetImpl::GetOrInsertNode(N));
522 /// FindNodeOrInsertPos - Look up the node specified by ID. If it
523 /// exists, return it. If not, return the insertion token that will
524 /// make insertion faster.
525 T *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos) {
526 return static_cast<T *>(FoldingSetImpl::FindNodeOrInsertPos(ID, InsertPos));
530 //===----------------------------------------------------------------------===//
531 /// FoldingSetVectorIterator - This implements an iterator for
532 /// FoldingSetVector. It is only necessary because FoldingSetIterator provides
533 /// a value_type of T, while the vector in FoldingSetVector exposes
534 /// a value_type of T*. Fortunately, FoldingSetIterator doesn't expose very
535 /// much besides operator* and operator->, so we just wrap the inner vector
536 /// iterator and perform the extra dereference.
537 template <class T, class VectorIteratorT>
538 class FoldingSetVectorIterator {
539 // Provide a typedef to workaround the lack of correct injected class name
540 // support in older GCCs.
541 typedef FoldingSetVectorIterator<T, VectorIteratorT> SelfT;
543 VectorIteratorT Iterator;
546 FoldingSetVectorIterator(VectorIteratorT I) : Iterator(I) {}
548 bool operator==(const SelfT &RHS) const {
549 return Iterator == RHS.Iterator;
551 bool operator!=(const SelfT &RHS) const {
552 return Iterator != RHS.Iterator;
555 T &operator*() const { return **Iterator; }
557 T *operator->() const { return *Iterator; }
559 inline SelfT &operator++() {
563 SelfT operator++(int) {
570 //===----------------------------------------------------------------------===//
571 /// FoldingSetVector - This template class combines a FoldingSet and a vector
572 /// to provide the interface of FoldingSet but with deterministic iteration
573 /// order based on the insertion order. T must be a subclass of FoldingSetNode
574 /// and implement a Profile function.
575 template <class T, class VectorT = SmallVector<T*, 8> >
576 class FoldingSetVector {
581 explicit FoldingSetVector(unsigned Log2InitSize = 6)
582 : Set(Log2InitSize) {
585 typedef FoldingSetVectorIterator<T, typename VectorT::iterator> iterator;
586 iterator begin() { return Vector.begin(); }
587 iterator end() { return Vector.end(); }
589 typedef FoldingSetVectorIterator<const T, typename VectorT::const_iterator>
591 const_iterator begin() const { return Vector.begin(); }
592 const_iterator end() const { return Vector.end(); }
594 /// clear - Remove all nodes from the folding set.
595 void clear() { Set.clear(); Vector.clear(); }
597 /// FindNodeOrInsertPos - Look up the node specified by ID. If it exists,
598 /// return it. If not, return the insertion token that will make insertion
600 T *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos) {
601 return Set.FindNodeOrInsertPos(ID, InsertPos);
604 /// GetOrInsertNode - If there is an existing simple Node exactly
605 /// equal to the specified node, return it. Otherwise, insert 'N' and
606 /// return it instead.
607 T *GetOrInsertNode(T *N) {
608 T *Result = Set.GetOrInsertNode(N);
609 if (Result == N) Vector.push_back(N);
613 /// InsertNode - Insert the specified node into the folding set, knowing that
614 /// it is not already in the folding set. InsertPos must be obtained from
615 /// FindNodeOrInsertPos.
616 void InsertNode(T *N, void *InsertPos) {
617 Set.InsertNode(N, InsertPos);
621 /// InsertNode - Insert the specified node into the folding set, knowing that
622 /// it is not already in the folding set.
623 void InsertNode(T *N) {
628 /// size - Returns the number of nodes in the folding set.
629 unsigned size() const { return Set.size(); }
631 /// empty - Returns true if there are no nodes in the folding set.
632 bool empty() const { return Set.empty(); }
635 //===----------------------------------------------------------------------===//
636 /// FoldingSetIteratorImpl - This is the common iterator support shared by all
637 /// folding sets, which knows how to walk the folding set hash table.
638 class FoldingSetIteratorImpl {
640 FoldingSetNode *NodePtr;
641 FoldingSetIteratorImpl(void **Bucket);
645 bool operator==(const FoldingSetIteratorImpl &RHS) const {
646 return NodePtr == RHS.NodePtr;
648 bool operator!=(const FoldingSetIteratorImpl &RHS) const {
649 return NodePtr != RHS.NodePtr;
655 class FoldingSetIterator : public FoldingSetIteratorImpl {
657 explicit FoldingSetIterator(void **Bucket) : FoldingSetIteratorImpl(Bucket) {}
659 T &operator*() const {
660 return *static_cast<T*>(NodePtr);
663 T *operator->() const {
664 return static_cast<T*>(NodePtr);
667 inline FoldingSetIterator &operator++() { // Preincrement
671 FoldingSetIterator operator++(int) { // Postincrement
672 FoldingSetIterator tmp = *this; ++*this; return tmp;
676 //===----------------------------------------------------------------------===//
677 /// FoldingSetBucketIteratorImpl - This is the common bucket iterator support
678 /// shared by all folding sets, which knows how to walk a particular bucket
679 /// of a folding set hash table.
681 class FoldingSetBucketIteratorImpl {
685 explicit FoldingSetBucketIteratorImpl(void **Bucket);
687 FoldingSetBucketIteratorImpl(void **Bucket, bool)
691 void *Probe = static_cast<FoldingSetNode*>(Ptr)->getNextInBucket();
692 uintptr_t x = reinterpret_cast<uintptr_t>(Probe) & ~0x1;
693 Ptr = reinterpret_cast<void*>(x);
697 bool operator==(const FoldingSetBucketIteratorImpl &RHS) const {
698 return Ptr == RHS.Ptr;
700 bool operator!=(const FoldingSetBucketIteratorImpl &RHS) const {
701 return Ptr != RHS.Ptr;
707 class FoldingSetBucketIterator : public FoldingSetBucketIteratorImpl {
709 explicit FoldingSetBucketIterator(void **Bucket) :
710 FoldingSetBucketIteratorImpl(Bucket) {}
712 FoldingSetBucketIterator(void **Bucket, bool) :
713 FoldingSetBucketIteratorImpl(Bucket, true) {}
715 T &operator*() const { return *static_cast<T*>(Ptr); }
716 T *operator->() const { return static_cast<T*>(Ptr); }
718 inline FoldingSetBucketIterator &operator++() { // Preincrement
722 FoldingSetBucketIterator operator++(int) { // Postincrement
723 FoldingSetBucketIterator tmp = *this; ++*this; return tmp;
727 //===----------------------------------------------------------------------===//
728 /// FoldingSetNodeWrapper - This template class is used to "wrap" arbitrary
729 /// types in an enclosing object so that they can be inserted into FoldingSets.
730 template <typename T>
731 class FoldingSetNodeWrapper : public FoldingSetNode {
734 explicit FoldingSetNodeWrapper(const T &x) : data(x) {}
735 virtual ~FoldingSetNodeWrapper() {}
737 template<typename A1>
738 explicit FoldingSetNodeWrapper(const A1 &a1)
741 template <typename A1, typename A2>
742 explicit FoldingSetNodeWrapper(const A1 &a1, const A2 &a2)
745 template <typename A1, typename A2, typename A3>
746 explicit FoldingSetNodeWrapper(const A1 &a1, const A2 &a2, const A3 &a3)
749 template <typename A1, typename A2, typename A3, typename A4>
750 explicit FoldingSetNodeWrapper(const A1 &a1, const A2 &a2, const A3 &a3,
752 : data(a1,a2,a3,a4) {}
754 template <typename A1, typename A2, typename A3, typename A4, typename A5>
755 explicit FoldingSetNodeWrapper(const A1 &a1, const A2 &a2, const A3 &a3,
756 const A4 &a4, const A5 &a5)
757 : data(a1,a2,a3,a4,a5) {}
760 void Profile(FoldingSetNodeID &ID) { FoldingSetTrait<T>::Profile(data, ID); }
762 T &getValue() { return data; }
763 const T &getValue() const { return data; }
765 operator T&() { return data; }
766 operator const T&() const { return data; }
769 //===----------------------------------------------------------------------===//
770 /// FastFoldingSetNode - This is a subclass of FoldingSetNode which stores
771 /// a FoldingSetNodeID value rather than requiring the node to recompute it
772 /// each time it is needed. This trades space for speed (which can be
773 /// significant if the ID is long), and it also permits nodes to drop
774 /// information that would otherwise only be required for recomputing an ID.
775 class FastFoldingSetNode : public FoldingSetNode {
776 FoldingSetNodeID FastID;
778 explicit FastFoldingSetNode(const FoldingSetNodeID &ID) : FastID(ID) {}
780 void Profile(FoldingSetNodeID &ID) const {
781 ID.AddNodeID(FastID);
785 //===----------------------------------------------------------------------===//
786 // Partial specializations of FoldingSetTrait.
788 template<typename T> struct FoldingSetTrait<T*> {
789 static inline void Profile(T *X, FoldingSetNodeID &ID) {
793 } // End of namespace llvm.