1 //===--- ImmutableSet.h - Immutable (functional) set interface --*- 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 the ImutAVLTree and ImmutableSet classes.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_ADT_IMMUTABLESET_H
15 #define LLVM_ADT_IMMUTABLESET_H
17 #include "llvm/ADT/DenseMap.h"
18 #include "llvm/ADT/FoldingSet.h"
19 #include "llvm/Support/Allocator.h"
20 #include "llvm/Support/DataTypes.h"
21 #include "llvm/Support/ErrorHandling.h"
28 //===----------------------------------------------------------------------===//
29 // Immutable AVL-Tree Definition.
30 //===----------------------------------------------------------------------===//
32 template <typename ImutInfo> class ImutAVLFactory;
33 template <typename ImutInfo> class ImutIntervalAVLFactory;
34 template <typename ImutInfo> class ImutAVLTreeInOrderIterator;
35 template <typename ImutInfo> class ImutAVLTreeGenericIterator;
37 template <typename ImutInfo >
40 typedef typename ImutInfo::key_type_ref key_type_ref;
41 typedef typename ImutInfo::value_type value_type;
42 typedef typename ImutInfo::value_type_ref value_type_ref;
44 typedef ImutAVLFactory<ImutInfo> Factory;
45 friend class ImutAVLFactory<ImutInfo>;
46 friend class ImutIntervalAVLFactory<ImutInfo>;
48 friend class ImutAVLTreeGenericIterator<ImutInfo>;
50 typedef ImutAVLTreeInOrderIterator<ImutInfo> iterator;
52 //===----------------------------------------------------===//
54 //===----------------------------------------------------===//
56 /// Return a pointer to the left subtree. This value
57 /// is NULL if there is no left subtree.
58 ImutAVLTree *getLeft() const { return left; }
60 /// Return a pointer to the right subtree. This value is
61 /// NULL if there is no right subtree.
62 ImutAVLTree *getRight() const { return right; }
64 /// getHeight - Returns the height of the tree. A tree with no subtrees
65 /// has a height of 1.
66 unsigned getHeight() const { return height; }
68 /// getValue - Returns the data value associated with the tree node.
69 const value_type& getValue() const { return value; }
71 /// find - Finds the subtree associated with the specified key value.
72 /// This method returns NULL if no matching subtree is found.
73 ImutAVLTree* find(key_type_ref K) {
74 ImutAVLTree *T = this;
76 key_type_ref CurrentKey = ImutInfo::KeyOfValue(T->getValue());
77 if (ImutInfo::isEqual(K,CurrentKey))
79 else if (ImutInfo::isLess(K,CurrentKey))
87 /// getMaxElement - Find the subtree associated with the highest ranged
89 ImutAVLTree* getMaxElement() {
90 ImutAVLTree *T = this;
91 ImutAVLTree *Right = T->getRight();
92 while (Right) { T = Right; Right = T->getRight(); }
96 /// size - Returns the number of nodes in the tree, which includes
97 /// both leaves and non-leaf nodes.
98 unsigned size() const {
100 if (const ImutAVLTree* L = getLeft())
102 if (const ImutAVLTree* R = getRight())
107 /// begin - Returns an iterator that iterates over the nodes of the tree
108 /// in an inorder traversal. The returned iterator thus refers to the
109 /// the tree node with the minimum data element.
110 iterator begin() const { return iterator(this); }
112 /// end - Returns an iterator for the tree that denotes the end of an
113 /// inorder traversal.
114 iterator end() const { return iterator(); }
116 bool isElementEqual(value_type_ref V) const {
118 if (!ImutInfo::isEqual(ImutInfo::KeyOfValue(getValue()),
119 ImutInfo::KeyOfValue(V)))
122 // Also compare the data values.
123 if (!ImutInfo::isDataEqual(ImutInfo::DataOfValue(getValue()),
124 ImutInfo::DataOfValue(V)))
130 bool isElementEqual(const ImutAVLTree* RHS) const {
131 return isElementEqual(RHS->getValue());
134 /// isEqual - Compares two trees for structural equality and returns true
135 /// if they are equal. This worst case performance of this operation is
136 // linear in the sizes of the trees.
137 bool isEqual(const ImutAVLTree& RHS) const {
141 iterator LItr = begin(), LEnd = end();
142 iterator RItr = RHS.begin(), REnd = RHS.end();
144 while (LItr != LEnd && RItr != REnd) {
145 if (*LItr == *RItr) {
151 if (!LItr->isElementEqual(*RItr))
158 return LItr == LEnd && RItr == REnd;
161 /// isNotEqual - Compares two trees for structural inequality. Performance
162 /// is the same is isEqual.
163 bool isNotEqual(const ImutAVLTree& RHS) const { return !isEqual(RHS); }
165 /// contains - Returns true if this tree contains a subtree (node) that
166 /// has an data element that matches the specified key. Complexity
167 /// is logarithmic in the size of the tree.
168 bool contains(key_type_ref K) { return (bool) find(K); }
170 /// foreach - A member template the accepts invokes operator() on a functor
171 /// object (specifed by Callback) for every node/subtree in the tree.
172 /// Nodes are visited using an inorder traversal.
173 template <typename Callback>
174 void foreach(Callback& C) {
175 if (ImutAVLTree* L = getLeft())
180 if (ImutAVLTree* R = getRight())
184 /// validateTree - A utility method that checks that the balancing and
185 /// ordering invariants of the tree are satisifed. It is a recursive
186 /// method that returns the height of the tree, which is then consumed
187 /// by the enclosing validateTree call. External callers should ignore the
188 /// return value. An invalid tree will cause an assertion to fire in
190 unsigned validateTree() const {
191 unsigned HL = getLeft() ? getLeft()->validateTree() : 0;
192 unsigned HR = getRight() ? getRight()->validateTree() : 0;
196 assert(getHeight() == ( HL > HR ? HL : HR ) + 1
197 && "Height calculation wrong");
199 assert((HL > HR ? HL-HR : HR-HL) <= 2
200 && "Balancing invariant violated");
202 assert((!getLeft() ||
203 ImutInfo::isLess(ImutInfo::KeyOfValue(getLeft()->getValue()),
204 ImutInfo::KeyOfValue(getValue()))) &&
205 "Value in left child is not less that current value");
208 assert(!(getRight() ||
209 ImutInfo::isLess(ImutInfo::KeyOfValue(getValue()),
210 ImutInfo::KeyOfValue(getRight()->getValue()))) &&
211 "Current value is not less that value of right child");
216 //===----------------------------------------------------===//
218 //===----------------------------------------------------===//
227 unsigned height : 28;
228 unsigned IsMutable : 1;
229 unsigned IsDigestCached : 1;
230 unsigned IsCanonicalized : 1;
236 //===----------------------------------------------------===//
237 // Internal methods (node manipulation; used by Factory).
238 //===----------------------------------------------------===//
241 /// ImutAVLTree - Internal constructor that is only called by
243 ImutAVLTree(Factory *f, ImutAVLTree* l, ImutAVLTree* r, value_type_ref v,
245 : factory(f), left(l), right(r), prev(0), next(0), height(height),
246 IsMutable(true), IsDigestCached(false), IsCanonicalized(0),
247 value(v), digest(0), refCount(0)
249 if (left) left->retain();
250 if (right) right->retain();
253 /// isMutable - Returns true if the left and right subtree references
254 /// (as well as height) can be changed. If this method returns false,
255 /// the tree is truly immutable. Trees returned from an ImutAVLFactory
256 /// object should always have this method return true. Further, if this
257 /// method returns false for an instance of ImutAVLTree, all subtrees
258 /// will also have this method return false. The converse is not true.
259 bool isMutable() const { return IsMutable; }
261 /// hasCachedDigest - Returns true if the digest for this tree is cached.
262 /// This can only be true if the tree is immutable.
263 bool hasCachedDigest() const { return IsDigestCached; }
265 //===----------------------------------------------------===//
266 // Mutating operations. A tree root can be manipulated as
267 // long as its reference has not "escaped" from internal
268 // methods of a factory object (see below). When a tree
269 // pointer is externally viewable by client code, the
270 // internal "mutable bit" is cleared to mark the tree
271 // immutable. Note that a tree that still has its mutable
272 // bit set may have children (subtrees) that are themselves
274 //===----------------------------------------------------===//
276 /// markImmutable - Clears the mutable flag for a tree. After this happens,
277 /// it is an error to call setLeft(), setRight(), and setHeight().
278 void markImmutable() {
279 assert(isMutable() && "Mutable flag already removed.");
283 /// markedCachedDigest - Clears the NoCachedDigest flag for a tree.
284 void markedCachedDigest() {
285 assert(!hasCachedDigest() && "NoCachedDigest flag already removed.");
286 IsDigestCached = true;
289 /// setHeight - Changes the height of the tree. Used internally by
291 void setHeight(unsigned h) {
292 assert(isMutable() && "Only a mutable tree can have its height changed.");
297 uint32_t computeDigest(ImutAVLTree* L, ImutAVLTree* R, value_type_ref V) {
301 digest += L->computeDigest();
303 // Compute digest of stored data.
305 ImutInfo::Profile(ID,V);
306 digest += ID.ComputeHash();
309 digest += R->computeDigest();
314 inline uint32_t computeDigest() {
315 // Check the lowest bit to determine if digest has actually been
317 if (hasCachedDigest())
320 uint32_t X = computeDigest(getLeft(), getRight(), getValue());
322 markedCachedDigest();
326 //===----------------------------------------------------===//
327 // Reference count operations.
328 //===----------------------------------------------------===//
331 void retain() { ++refCount; }
333 assert(refCount > 0);
342 if (IsCanonicalized) {
349 factory->Cache[factory->maskCacheIndex(computeDigest())] = next;
352 // We need to clear the mutability bit in case we are
353 // destroying the node as part of a sweep in ImutAVLFactory::recoverNodes().
355 factory->freeNodes.push_back(this);
359 //===----------------------------------------------------------------------===//
360 // Immutable AVL-Tree Factory class.
361 //===----------------------------------------------------------------------===//
363 template <typename ImutInfo >
364 class ImutAVLFactory {
365 friend class ImutAVLTree<ImutInfo>;
366 typedef ImutAVLTree<ImutInfo> TreeTy;
367 typedef typename TreeTy::value_type_ref value_type_ref;
368 typedef typename TreeTy::key_type_ref key_type_ref;
370 typedef DenseMap<unsigned, TreeTy*> CacheTy;
374 std::vector<TreeTy*> createdNodes;
375 std::vector<TreeTy*> freeNodes;
377 bool ownsAllocator() const {
378 return Allocator & 0x1 ? false : true;
381 BumpPtrAllocator& getAllocator() const {
382 return *reinterpret_cast<BumpPtrAllocator*>(Allocator & ~0x1);
385 //===--------------------------------------------------===//
387 //===--------------------------------------------------===//
391 : Allocator(reinterpret_cast<uintptr_t>(new BumpPtrAllocator())) {}
393 ImutAVLFactory(BumpPtrAllocator& Alloc)
394 : Allocator(reinterpret_cast<uintptr_t>(&Alloc) | 0x1) {}
397 if (ownsAllocator()) delete &getAllocator();
400 TreeTy* add(TreeTy* T, value_type_ref V) {
401 T = add_internal(V,T);
407 TreeTy* remove(TreeTy* T, key_type_ref V) {
408 T = remove_internal(V,T);
414 TreeTy* getEmptyTree() const { return NULL; }
418 //===--------------------------------------------------===//
419 // A bunch of quick helper functions used for reasoning
420 // about the properties of trees and their children.
421 // These have succinct names so that the balancing code
422 // is as terse (and readable) as possible.
423 //===--------------------------------------------------===//
425 bool isEmpty(TreeTy* T) const { return !T; }
426 unsigned getHeight(TreeTy* T) const { return T ? T->getHeight() : 0; }
427 TreeTy* getLeft(TreeTy* T) const { return T->getLeft(); }
428 TreeTy* getRight(TreeTy* T) const { return T->getRight(); }
429 value_type_ref getValue(TreeTy* T) const { return T->value; }
431 // Make sure the index is not the Tombstone or Entry key of the DenseMap.
432 static inline unsigned maskCacheIndex(unsigned I) {
436 unsigned incrementHeight(TreeTy* L, TreeTy* R) const {
437 unsigned hl = getHeight(L);
438 unsigned hr = getHeight(R);
439 return (hl > hr ? hl : hr) + 1;
442 static bool compareTreeWithSection(TreeTy* T,
443 typename TreeTy::iterator& TI,
444 typename TreeTy::iterator& TE) {
445 typename TreeTy::iterator I = T->begin(), E = T->end();
446 for ( ; I!=E ; ++I, ++TI) {
447 if (TI == TE || !I->isElementEqual(*TI))
453 //===--------------------------------------------------===//
454 // "createNode" is used to generate new tree roots that link
455 // to other trees. The functon may also simply move links
456 // in an existing root if that root is still marked mutable.
457 // This is necessary because otherwise our balancing code
458 // would leak memory as it would create nodes that are
459 // then discarded later before the finished tree is
460 // returned to the caller.
461 //===--------------------------------------------------===//
463 TreeTy* createNode(TreeTy* L, value_type_ref V, TreeTy* R) {
464 BumpPtrAllocator& A = getAllocator();
466 if (!freeNodes.empty()) {
467 T = freeNodes.back();
468 freeNodes.pop_back();
472 T = (TreeTy*) A.Allocate<TreeTy>();
474 new (T) TreeTy(this, L, R, V, incrementHeight(L,R));
475 createdNodes.push_back(T);
479 TreeTy* createNode(TreeTy* newLeft, TreeTy* oldTree, TreeTy* newRight) {
480 return createNode(newLeft, getValue(oldTree), newRight);
483 void recoverNodes() {
484 for (unsigned i = 0, n = createdNodes.size(); i < n; ++i) {
485 TreeTy *N = createdNodes[i];
486 if (N->isMutable() && N->refCount == 0)
489 createdNodes.clear();
492 /// balanceTree - Used by add_internal and remove_internal to
493 /// balance a newly created tree.
494 TreeTy* balanceTree(TreeTy* L, value_type_ref V, TreeTy* R) {
495 unsigned hl = getHeight(L);
496 unsigned hr = getHeight(R);
499 assert(!isEmpty(L) && "Left tree cannot be empty to have a height >= 2");
501 TreeTy *LL = getLeft(L);
502 TreeTy *LR = getRight(L);
504 if (getHeight(LL) >= getHeight(LR))
505 return createNode(LL, L, createNode(LR,V,R));
507 assert(!isEmpty(LR) && "LR cannot be empty because it has a height >= 1");
509 TreeTy *LRL = getLeft(LR);
510 TreeTy *LRR = getRight(LR);
512 return createNode(createNode(LL,L,LRL), LR, createNode(LRR,V,R));
516 assert(!isEmpty(R) && "Right tree cannot be empty to have a height >= 2");
518 TreeTy *RL = getLeft(R);
519 TreeTy *RR = getRight(R);
521 if (getHeight(RR) >= getHeight(RL))
522 return createNode(createNode(L,V,RL), R, RR);
524 assert(!isEmpty(RL) && "RL cannot be empty because it has a height >= 1");
526 TreeTy *RLL = getLeft(RL);
527 TreeTy *RLR = getRight(RL);
529 return createNode(createNode(L,V,RLL), RL, createNode(RLR,R,RR));
532 return createNode(L,V,R);
535 /// add_internal - Creates a new tree that includes the specified
536 /// data and the data from the original tree. If the original tree
537 /// already contained the data item, the original tree is returned.
538 TreeTy* add_internal(value_type_ref V, TreeTy* T) {
540 return createNode(T, V, T);
541 assert(!T->isMutable());
543 key_type_ref K = ImutInfo::KeyOfValue(V);
544 key_type_ref KCurrent = ImutInfo::KeyOfValue(getValue(T));
546 if (ImutInfo::isEqual(K,KCurrent))
547 return createNode(getLeft(T), V, getRight(T));
548 else if (ImutInfo::isLess(K,KCurrent))
549 return balanceTree(add_internal(V, getLeft(T)), getValue(T), getRight(T));
551 return balanceTree(getLeft(T), getValue(T), add_internal(V, getRight(T)));
554 /// remove_internal - Creates a new tree that includes all the data
555 /// from the original tree except the specified data. If the
556 /// specified data did not exist in the original tree, the original
557 /// tree is returned.
558 TreeTy* remove_internal(key_type_ref K, TreeTy* T) {
562 assert(!T->isMutable());
564 key_type_ref KCurrent = ImutInfo::KeyOfValue(getValue(T));
566 if (ImutInfo::isEqual(K,KCurrent)) {
567 return combineTrees(getLeft(T), getRight(T));
568 } else if (ImutInfo::isLess(K,KCurrent)) {
569 return balanceTree(remove_internal(K, getLeft(T)),
570 getValue(T), getRight(T));
572 return balanceTree(getLeft(T), getValue(T),
573 remove_internal(K, getRight(T)));
577 TreeTy* combineTrees(TreeTy* L, TreeTy* R) {
583 TreeTy* newRight = removeMinBinding(R,OldNode);
584 return balanceTree(L, getValue(OldNode), newRight);
587 TreeTy* removeMinBinding(TreeTy* T, TreeTy*& Noderemoved) {
589 if (isEmpty(getLeft(T))) {
593 return balanceTree(removeMinBinding(getLeft(T), Noderemoved),
594 getValue(T), getRight(T));
597 /// markImmutable - Clears the mutable bits of a root and all of its
599 void markImmutable(TreeTy* T) {
600 if (!T || !T->isMutable())
603 markImmutable(getLeft(T));
604 markImmutable(getRight(T));
608 TreeTy *getCanonicalTree(TreeTy *TNew) {
612 if (TNew->IsCanonicalized)
615 // Search the hashtable for another tree with the same digest, and
616 // if find a collision compare those trees by their contents.
617 unsigned digest = TNew->computeDigest();
618 TreeTy *&entry = Cache[maskCacheIndex(digest)];
622 for (TreeTy *T = entry ; T != 0; T = T->next) {
623 // Compare the Contents('T') with Contents('TNew')
624 typename TreeTy::iterator TI = T->begin(), TE = T->end();
625 if (!compareTreeWithSection(TNew, TI, TE))
628 continue; // T has more contents than TNew.
629 // Trees did match! Return 'T'.
630 if (TNew->refCount == 0)
640 TNew->IsCanonicalized = true;
645 //===----------------------------------------------------------------------===//
646 // Immutable AVL-Tree Iterators.
647 //===----------------------------------------------------------------------===//
649 template <typename ImutInfo>
650 class ImutAVLTreeGenericIterator {
651 SmallVector<uintptr_t,20> stack;
653 enum VisitFlag { VisitedNone=0x0, VisitedLeft=0x1, VisitedRight=0x3,
656 typedef ImutAVLTree<ImutInfo> TreeTy;
657 typedef ImutAVLTreeGenericIterator<ImutInfo> _Self;
659 inline ImutAVLTreeGenericIterator() {}
660 inline ImutAVLTreeGenericIterator(const TreeTy* Root) {
661 if (Root) stack.push_back(reinterpret_cast<uintptr_t>(Root));
664 TreeTy* operator*() const {
665 assert(!stack.empty());
666 return reinterpret_cast<TreeTy*>(stack.back() & ~Flags);
669 uintptr_t getVisitState() const {
670 assert(!stack.empty());
671 return stack.back() & Flags;
675 bool atEnd() const { return stack.empty(); }
677 bool atBeginning() const {
678 return stack.size() == 1 && getVisitState() == VisitedNone;
681 void skipToParent() {
682 assert(!stack.empty());
686 switch (getVisitState()) {
688 stack.back() |= VisitedLeft;
691 stack.back() |= VisitedRight;
694 llvm_unreachable("Unreachable.");
698 inline bool operator==(const _Self& x) const {
699 return stack == x.stack;
702 inline bool operator!=(const _Self& x) const { return !operator==(x); }
704 _Self& operator++() {
705 assert(!stack.empty());
706 TreeTy* Current = reinterpret_cast<TreeTy*>(stack.back() & ~Flags);
708 switch (getVisitState()) {
710 if (TreeTy* L = Current->getLeft())
711 stack.push_back(reinterpret_cast<uintptr_t>(L));
713 stack.back() |= VisitedLeft;
716 if (TreeTy* R = Current->getRight())
717 stack.push_back(reinterpret_cast<uintptr_t>(R));
719 stack.back() |= VisitedRight;
725 llvm_unreachable("Unreachable.");
730 _Self& operator--() {
731 assert(!stack.empty());
732 TreeTy* Current = reinterpret_cast<TreeTy*>(stack.back() & ~Flags);
734 switch (getVisitState()) {
739 stack.back() &= ~Flags; // Set state to "VisitedNone."
740 if (TreeTy* L = Current->getLeft())
741 stack.push_back(reinterpret_cast<uintptr_t>(L) | VisitedRight);
744 stack.back() &= ~Flags;
745 stack.back() |= VisitedLeft;
746 if (TreeTy* R = Current->getRight())
747 stack.push_back(reinterpret_cast<uintptr_t>(R) | VisitedRight);
750 llvm_unreachable("Unreachable.");
756 template <typename ImutInfo>
757 class ImutAVLTreeInOrderIterator {
758 typedef ImutAVLTreeGenericIterator<ImutInfo> InternalIteratorTy;
759 InternalIteratorTy InternalItr;
762 typedef ImutAVLTree<ImutInfo> TreeTy;
763 typedef ImutAVLTreeInOrderIterator<ImutInfo> _Self;
765 ImutAVLTreeInOrderIterator(const TreeTy* Root) : InternalItr(Root) {
766 if (Root) operator++(); // Advance to first element.
769 ImutAVLTreeInOrderIterator() : InternalItr() {}
771 inline bool operator==(const _Self& x) const {
772 return InternalItr == x.InternalItr;
775 inline bool operator!=(const _Self& x) const { return !operator==(x); }
777 inline TreeTy* operator*() const { return *InternalItr; }
778 inline TreeTy* operator->() const { return *InternalItr; }
780 inline _Self& operator++() {
782 while (!InternalItr.atEnd() &&
783 InternalItr.getVisitState() != InternalIteratorTy::VisitedLeft);
788 inline _Self& operator--() {
790 while (!InternalItr.atBeginning() &&
791 InternalItr.getVisitState() != InternalIteratorTy::VisitedLeft);
796 inline void skipSubTree() {
797 InternalItr.skipToParent();
799 while (!InternalItr.atEnd() &&
800 InternalItr.getVisitState() != InternalIteratorTy::VisitedLeft)
805 //===----------------------------------------------------------------------===//
806 // Trait classes for Profile information.
807 //===----------------------------------------------------------------------===//
809 /// Generic profile template. The default behavior is to invoke the
810 /// profile method of an object. Specializations for primitive integers
811 /// and generic handling of pointers is done below.
812 template <typename T>
813 struct ImutProfileInfo {
814 typedef const T value_type;
815 typedef const T& value_type_ref;
817 static inline void Profile(FoldingSetNodeID& ID, value_type_ref X) {
818 FoldingSetTrait<T>::Profile(X,ID);
822 /// Profile traits for integers.
823 template <typename T>
824 struct ImutProfileInteger {
825 typedef const T value_type;
826 typedef const T& value_type_ref;
828 static inline void Profile(FoldingSetNodeID& ID, value_type_ref X) {
833 #define PROFILE_INTEGER_INFO(X)\
834 template<> struct ImutProfileInfo<X> : ImutProfileInteger<X> {};
836 PROFILE_INTEGER_INFO(char)
837 PROFILE_INTEGER_INFO(unsigned char)
838 PROFILE_INTEGER_INFO(short)
839 PROFILE_INTEGER_INFO(unsigned short)
840 PROFILE_INTEGER_INFO(unsigned)
841 PROFILE_INTEGER_INFO(signed)
842 PROFILE_INTEGER_INFO(long)
843 PROFILE_INTEGER_INFO(unsigned long)
844 PROFILE_INTEGER_INFO(long long)
845 PROFILE_INTEGER_INFO(unsigned long long)
847 #undef PROFILE_INTEGER_INFO
849 /// Profile traits for booleans.
851 struct ImutProfileInfo<bool> {
852 typedef const bool value_type;
853 typedef const bool& value_type_ref;
855 static inline void Profile(FoldingSetNodeID& ID, value_type_ref X) {
861 /// Generic profile trait for pointer types. We treat pointers as
862 /// references to unique objects.
863 template <typename T>
864 struct ImutProfileInfo<T*> {
865 typedef const T* value_type;
866 typedef value_type value_type_ref;
868 static inline void Profile(FoldingSetNodeID &ID, value_type_ref X) {
873 //===----------------------------------------------------------------------===//
874 // Trait classes that contain element comparison operators and type
875 // definitions used by ImutAVLTree, ImmutableSet, and ImmutableMap. These
876 // inherit from the profile traits (ImutProfileInfo) to include operations
877 // for element profiling.
878 //===----------------------------------------------------------------------===//
881 /// ImutContainerInfo - Generic definition of comparison operations for
882 /// elements of immutable containers that defaults to using
883 /// std::equal_to<> and std::less<> to perform comparison of elements.
884 template <typename T>
885 struct ImutContainerInfo : public ImutProfileInfo<T> {
886 typedef typename ImutProfileInfo<T>::value_type value_type;
887 typedef typename ImutProfileInfo<T>::value_type_ref value_type_ref;
888 typedef value_type key_type;
889 typedef value_type_ref key_type_ref;
890 typedef bool data_type;
891 typedef bool data_type_ref;
893 static inline key_type_ref KeyOfValue(value_type_ref D) { return D; }
894 static inline data_type_ref DataOfValue(value_type_ref) { return true; }
896 static inline bool isEqual(key_type_ref LHS, key_type_ref RHS) {
897 return std::equal_to<key_type>()(LHS,RHS);
900 static inline bool isLess(key_type_ref LHS, key_type_ref RHS) {
901 return std::less<key_type>()(LHS,RHS);
904 static inline bool isDataEqual(data_type_ref,data_type_ref) { return true; }
907 /// ImutContainerInfo - Specialization for pointer values to treat pointers
908 /// as references to unique objects. Pointers are thus compared by
910 template <typename T>
911 struct ImutContainerInfo<T*> : public ImutProfileInfo<T*> {
912 typedef typename ImutProfileInfo<T*>::value_type value_type;
913 typedef typename ImutProfileInfo<T*>::value_type_ref value_type_ref;
914 typedef value_type key_type;
915 typedef value_type_ref key_type_ref;
916 typedef bool data_type;
917 typedef bool data_type_ref;
919 static inline key_type_ref KeyOfValue(value_type_ref D) { return D; }
920 static inline data_type_ref DataOfValue(value_type_ref) { return true; }
922 static inline bool isEqual(key_type_ref LHS, key_type_ref RHS) {
926 static inline bool isLess(key_type_ref LHS, key_type_ref RHS) {
930 static inline bool isDataEqual(data_type_ref,data_type_ref) { return true; }
933 //===----------------------------------------------------------------------===//
935 //===----------------------------------------------------------------------===//
937 template <typename ValT, typename ValInfo = ImutContainerInfo<ValT> >
940 typedef typename ValInfo::value_type value_type;
941 typedef typename ValInfo::value_type_ref value_type_ref;
942 typedef ImutAVLTree<ValInfo> TreeTy;
948 /// Constructs a set from a pointer to a tree root. In general one
949 /// should use a Factory object to create sets instead of directly
950 /// invoking the constructor, but there are cases where make this
951 /// constructor public is useful.
952 explicit ImmutableSet(TreeTy* R) : Root(R) {
953 if (Root) { Root->retain(); }
955 ImmutableSet(const ImmutableSet &X) : Root(X.Root) {
956 if (Root) { Root->retain(); }
958 ImmutableSet &operator=(const ImmutableSet &X) {
959 if (Root != X.Root) {
960 if (X.Root) { X.Root->retain(); }
961 if (Root) { Root->release(); }
967 if (Root) { Root->release(); }
971 typename TreeTy::Factory F;
972 const bool Canonicalize;
975 Factory(bool canonicalize = true)
976 : Canonicalize(canonicalize) {}
978 Factory(BumpPtrAllocator& Alloc, bool canonicalize = true)
979 : F(Alloc), Canonicalize(canonicalize) {}
981 /// getEmptySet - Returns an immutable set that contains no elements.
982 ImmutableSet getEmptySet() {
983 return ImmutableSet(F.getEmptyTree());
986 /// add - Creates a new immutable set that contains all of the values
987 /// of the original set with the addition of the specified value. If
988 /// the original set already included the value, then the original set is
989 /// returned and no memory is allocated. The time and space complexity
990 /// of this operation is logarithmic in the size of the original set.
991 /// The memory allocated to represent the set is released when the
992 /// factory object that created the set is destroyed.
993 ImmutableSet add(ImmutableSet Old, value_type_ref V) {
994 TreeTy *NewT = F.add(Old.Root, V);
995 return ImmutableSet(Canonicalize ? F.getCanonicalTree(NewT) : NewT);
998 /// remove - Creates a new immutable set that contains all of the values
999 /// of the original set with the exception of the specified value. If
1000 /// the original set did not contain the value, the original set is
1001 /// returned and no memory is allocated. The time and space complexity
1002 /// of this operation is logarithmic in the size of the original set.
1003 /// The memory allocated to represent the set is released when the
1004 /// factory object that created the set is destroyed.
1005 ImmutableSet remove(ImmutableSet Old, value_type_ref V) {
1006 TreeTy *NewT = F.remove(Old.Root, V);
1007 return ImmutableSet(Canonicalize ? F.getCanonicalTree(NewT) : NewT);
1010 BumpPtrAllocator& getAllocator() { return F.getAllocator(); }
1012 typename TreeTy::Factory *getTreeFactory() const {
1013 return const_cast<typename TreeTy::Factory *>(&F);
1017 Factory(const Factory& RHS) LLVM_DELETED_FUNCTION;
1018 void operator=(const Factory& RHS) LLVM_DELETED_FUNCTION;
1021 friend class Factory;
1023 /// Returns true if the set contains the specified value.
1024 bool contains(value_type_ref V) const {
1025 return Root ? Root->contains(V) : false;
1028 bool operator==(const ImmutableSet &RHS) const {
1029 return Root && RHS.Root ? Root->isEqual(*RHS.Root) : Root == RHS.Root;
1032 bool operator!=(const ImmutableSet &RHS) const {
1033 return Root && RHS.Root ? Root->isNotEqual(*RHS.Root) : Root != RHS.Root;
1037 if (Root) { Root->retain(); }
1041 TreeTy *getRootWithoutRetain() const {
1045 /// isEmpty - Return true if the set contains no elements.
1046 bool isEmpty() const { return !Root; }
1048 /// isSingleton - Return true if the set contains exactly one element.
1049 /// This method runs in constant time.
1050 bool isSingleton() const { return getHeight() == 1; }
1052 template <typename Callback>
1053 void foreach(Callback& C) { if (Root) Root->foreach(C); }
1055 template <typename Callback>
1056 void foreach() { if (Root) { Callback C; Root->foreach(C); } }
1058 //===--------------------------------------------------===//
1060 //===--------------------------------------------------===//
1063 typename TreeTy::iterator itr;
1066 iterator(TreeTy* t) : itr(t) {}
1067 friend class ImmutableSet<ValT,ValInfo>;
1070 typedef ptrdiff_t difference_type;
1071 typedef typename ImmutableSet<ValT,ValInfo>::value_type value_type;
1072 typedef typename ImmutableSet<ValT,ValInfo>::value_type_ref reference;
1073 typedef typename iterator::value_type *pointer;
1074 typedef std::bidirectional_iterator_tag iterator_category;
1076 typename iterator::reference operator*() const { return itr->getValue(); }
1077 typename iterator::pointer operator->() const { return &(operator*()); }
1079 iterator& operator++() { ++itr; return *this; }
1080 iterator operator++(int) { iterator tmp(*this); ++itr; return tmp; }
1081 iterator& operator--() { --itr; return *this; }
1082 iterator operator--(int) { iterator tmp(*this); --itr; return tmp; }
1084 bool operator==(const iterator& RHS) const { return RHS.itr == itr; }
1085 bool operator!=(const iterator& RHS) const { return RHS.itr != itr; }
1088 iterator begin() const { return iterator(Root); }
1089 iterator end() const { return iterator(); }
1091 //===--------------------------------------------------===//
1093 //===--------------------------------------------------===//
1095 unsigned getHeight() const { return Root ? Root->getHeight() : 0; }
1097 static inline void Profile(FoldingSetNodeID& ID, const ImmutableSet& S) {
1098 ID.AddPointer(S.Root);
1101 inline void Profile(FoldingSetNodeID& ID) const {
1102 return Profile(ID,*this);
1105 //===--------------------------------------------------===//
1107 //===--------------------------------------------------===//
1109 void validateTree() const { if (Root) Root->validateTree(); }
1112 // NOTE: This may some day replace the current ImmutableSet.
1113 template <typename ValT, typename ValInfo = ImutContainerInfo<ValT> >
1114 class ImmutableSetRef {
1116 typedef typename ValInfo::value_type value_type;
1117 typedef typename ValInfo::value_type_ref value_type_ref;
1118 typedef ImutAVLTree<ValInfo> TreeTy;
1119 typedef typename TreeTy::Factory FactoryTy;
1126 /// Constructs a set from a pointer to a tree root. In general one
1127 /// should use a Factory object to create sets instead of directly
1128 /// invoking the constructor, but there are cases where make this
1129 /// constructor public is useful.
1130 explicit ImmutableSetRef(TreeTy* R, FactoryTy *F)
1133 if (Root) { Root->retain(); }
1135 ImmutableSetRef(const ImmutableSetRef &X)
1137 Factory(X.Factory) {
1138 if (Root) { Root->retain(); }
1140 ImmutableSetRef &operator=(const ImmutableSetRef &X) {
1141 if (Root != X.Root) {
1142 if (X.Root) { X.Root->retain(); }
1143 if (Root) { Root->release(); }
1145 Factory = X.Factory;
1149 ~ImmutableSetRef() {
1150 if (Root) { Root->release(); }
1153 static inline ImmutableSetRef getEmptySet(FactoryTy *F) {
1154 return ImmutableSetRef(0, F);
1157 ImmutableSetRef add(value_type_ref V) {
1158 return ImmutableSetRef(Factory->add(Root, V), Factory);
1161 ImmutableSetRef remove(value_type_ref V) {
1162 return ImmutableSetRef(Factory->remove(Root, V), Factory);
1165 /// Returns true if the set contains the specified value.
1166 bool contains(value_type_ref V) const {
1167 return Root ? Root->contains(V) : false;
1170 ImmutableSet<ValT> asImmutableSet(bool canonicalize = true) const {
1171 return ImmutableSet<ValT>(canonicalize ?
1172 Factory->getCanonicalTree(Root) : Root);
1175 TreeTy *getRootWithoutRetain() const {
1179 bool operator==(const ImmutableSetRef &RHS) const {
1180 return Root && RHS.Root ? Root->isEqual(*RHS.Root) : Root == RHS.Root;
1183 bool operator!=(const ImmutableSetRef &RHS) const {
1184 return Root && RHS.Root ? Root->isNotEqual(*RHS.Root) : Root != RHS.Root;
1187 /// isEmpty - Return true if the set contains no elements.
1188 bool isEmpty() const { return !Root; }
1190 /// isSingleton - Return true if the set contains exactly one element.
1191 /// This method runs in constant time.
1192 bool isSingleton() const { return getHeight() == 1; }
1194 //===--------------------------------------------------===//
1196 //===--------------------------------------------------===//
1199 typename TreeTy::iterator itr;
1200 iterator(TreeTy* t) : itr(t) {}
1201 friend class ImmutableSetRef<ValT,ValInfo>;
1204 inline value_type_ref operator*() const { return itr->getValue(); }
1205 inline iterator& operator++() { ++itr; return *this; }
1206 inline iterator operator++(int) { iterator tmp(*this); ++itr; return tmp; }
1207 inline iterator& operator--() { --itr; return *this; }
1208 inline iterator operator--(int) { iterator tmp(*this); --itr; return tmp; }
1209 inline bool operator==(const iterator& RHS) const { return RHS.itr == itr; }
1210 inline bool operator!=(const iterator& RHS) const { return RHS.itr != itr; }
1211 inline value_type *operator->() const { return &(operator*()); }
1214 iterator begin() const { return iterator(Root); }
1215 iterator end() const { return iterator(); }
1217 //===--------------------------------------------------===//
1219 //===--------------------------------------------------===//
1221 unsigned getHeight() const { return Root ? Root->getHeight() : 0; }
1223 static inline void Profile(FoldingSetNodeID& ID, const ImmutableSetRef& S) {
1224 ID.AddPointer(S.Root);
1227 inline void Profile(FoldingSetNodeID& ID) const {
1228 return Profile(ID,*this);
1231 //===--------------------------------------------------===//
1233 //===--------------------------------------------------===//
1235 void validateTree() const { if (Root) Root->validateTree(); }
1238 } // end namespace llvm