| //===-- llvm/ADT/ilist - Intrusive Linked List Template ---------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file defines classes to implement an intrusive doubly linked list class |
| // (i.e. each node of the list must contain a next and previous field for the |
| // list. |
| // |
| // The ilist_traits trait class is used to gain access to the next and previous |
| // fields of the node type that the list is instantiated with. If it is not |
| // specialized, the list defaults to using the getPrev(), getNext() method calls |
| // to get the next and previous pointers. |
| // |
| // The ilist class itself, should be a plug in replacement for list, assuming |
| // that the nodes contain next/prev pointers. This list replacement does not |
| // provides a constant time size() method, so be careful to use empty() when you |
| // really want to know if it's empty. |
| // |
| // The ilist class is implemented by allocating a 'tail' node when the list is |
| // created (using ilist_traits<>::createSentinel()). This tail node is |
| // absolutely required because the user must be able to compute end()-1. Because |
| // of this, users of the direct next/prev links will see an extra link on the |
| // end of the list, which should be ignored. |
| // |
| // Requirements for a user of this list: |
| // |
| // 1. The user must provide {g|s}et{Next|Prev} methods, or specialize |
| // ilist_traits to provide an alternate way of getting and setting next and |
| // prev links. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_ADT_ILIST |
| #define LLVM_ADT_ILIST |
| |
| #include "llvm/ADT/iterator" |
| #include <cassert> |
| |
| namespace llvm { |
| |
| template<typename NodeTy, typename Traits> class iplist; |
| template<typename NodeTy> class ilist_iterator; |
| |
| // Template traits for intrusive list. By specializing this template class, you |
| // can change what next/prev fields are used to store the links... |
| template<typename NodeTy> |
| struct ilist_traits { |
| static NodeTy *getPrev(NodeTy *N) { return N->getPrev(); } |
| static NodeTy *getNext(NodeTy *N) { return N->getNext(); } |
| static const NodeTy *getPrev(const NodeTy *N) { return N->getPrev(); } |
| static const NodeTy *getNext(const NodeTy *N) { return N->getNext(); } |
| |
| static void setPrev(NodeTy *N, NodeTy *Prev) { N->setPrev(Prev); } |
| static void setNext(NodeTy *N, NodeTy *Next) { N->setNext(Next); } |
| |
| static NodeTy *createNode(const NodeTy &V) { return new NodeTy(V); } |
| |
| static NodeTy *createSentinel() { return new NodeTy(); } |
| static void destroySentinel(NodeTy *N) { delete N; } |
| |
| void addNodeToList(NodeTy *NTy) {} |
| void removeNodeFromList(NodeTy *NTy) {} |
| void transferNodesFromList(iplist<NodeTy, ilist_traits> &L2, |
| ilist_iterator<NodeTy> first, |
| ilist_iterator<NodeTy> last) {} |
| }; |
| |
| // Const traits are the same as nonconst traits... |
| template<typename Ty> |
| struct ilist_traits<const Ty> : public ilist_traits<Ty> {}; |
| |
| |
| //===----------------------------------------------------------------------===// |
| // ilist_iterator<Node> - Iterator for intrusive list. |
| // |
| template<typename NodeTy> |
| class ilist_iterator |
| : public bidirectional_iterator<NodeTy, ptrdiff_t> { |
| typedef ilist_traits<NodeTy> Traits; |
| typedef bidirectional_iterator<NodeTy, ptrdiff_t> super; |
| |
| public: |
| typedef size_t size_type; |
| typedef typename super::pointer pointer; |
| typedef typename super::reference reference; |
| private: |
| pointer NodePtr; |
| public: |
| |
| ilist_iterator(pointer NP) : NodePtr(NP) {} |
| ilist_iterator(reference NR) : NodePtr(&NR) {} |
| ilist_iterator() : NodePtr(0) {} |
| |
| // This is templated so that we can allow constructing a const iterator from |
| // a nonconst iterator... |
| template<class node_ty> |
| ilist_iterator(const ilist_iterator<node_ty> &RHS) |
| : NodePtr(RHS.getNodePtrUnchecked()) {} |
| |
| // This is templated so that we can allow assigning to a const iterator from |
| // a nonconst iterator... |
| template<class node_ty> |
| const ilist_iterator &operator=(const ilist_iterator<node_ty> &RHS) { |
| NodePtr = RHS.getNodePtrUnchecked(); |
| return *this; |
| } |
| |
| // Accessors... |
| operator pointer() const { |
| assert(Traits::getNext(NodePtr) != 0 && "Dereferencing end()!"); |
| return NodePtr; |
| } |
| |
| reference operator*() const { |
| assert(Traits::getNext(NodePtr) != 0 && "Dereferencing end()!"); |
| return *NodePtr; |
| } |
| pointer operator->() { return &operator*(); } |
| const pointer operator->() const { return &operator*(); } |
| |
| // Comparison operators |
| bool operator==(const ilist_iterator &RHS) const { |
| return NodePtr == RHS.NodePtr; |
| } |
| bool operator!=(const ilist_iterator &RHS) const { |
| return NodePtr != RHS.NodePtr; |
| } |
| |
| // Increment and decrement operators... |
| ilist_iterator &operator--() { // predecrement - Back up |
| NodePtr = Traits::getPrev(NodePtr); |
| assert(Traits::getNext(NodePtr) && "--'d off the beginning of an ilist!"); |
| return *this; |
| } |
| ilist_iterator &operator++() { // preincrement - Advance |
| NodePtr = Traits::getNext(NodePtr); |
| assert(NodePtr && "++'d off the end of an ilist!"); |
| return *this; |
| } |
| ilist_iterator operator--(int) { // postdecrement operators... |
| ilist_iterator tmp = *this; |
| --*this; |
| return tmp; |
| } |
| ilist_iterator operator++(int) { // postincrement operators... |
| ilist_iterator tmp = *this; |
| ++*this; |
| return tmp; |
| } |
| |
| // Internal interface, do not use... |
| pointer getNodePtrUnchecked() const { return NodePtr; } |
| }; |
| |
| // do not implement. this is to catch errors when people try to use |
| // them as random access iterators |
| template<typename T> |
| void operator-(int, ilist_iterator<T>); |
| template<typename T> |
| void operator-(ilist_iterator<T>,int); |
| |
| template<typename T> |
| void operator+(int, ilist_iterator<T>); |
| template<typename T> |
| void operator+(ilist_iterator<T>,int); |
| |
| // operator!=/operator== - Allow mixed comparisons without dereferencing |
| // the iterator, which could very likely be pointing to end(). |
| template<typename T> |
| bool operator!=(const T* LHS, const ilist_iterator<const T> &RHS) { |
| return LHS != RHS.getNodePtrUnchecked(); |
| } |
| template<typename T> |
| bool operator==(const T* LHS, const ilist_iterator<const T> &RHS) { |
| return LHS == RHS.getNodePtrUnchecked(); |
| } |
| template<typename T> |
| bool operator!=(T* LHS, const ilist_iterator<T> &RHS) { |
| return LHS != RHS.getNodePtrUnchecked(); |
| } |
| template<typename T> |
| bool operator==(T* LHS, const ilist_iterator<T> &RHS) { |
| return LHS == RHS.getNodePtrUnchecked(); |
| } |
| |
| |
| // Allow ilist_iterators to convert into pointers to a node automatically when |
| // used by the dyn_cast, cast, isa mechanisms... |
| |
| template<typename From> struct simplify_type; |
| |
| template<typename NodeTy> struct simplify_type<ilist_iterator<NodeTy> > { |
| typedef NodeTy* SimpleType; |
| |
| static SimpleType getSimplifiedValue(const ilist_iterator<NodeTy> &Node) { |
| return &*Node; |
| } |
| }; |
| template<typename NodeTy> struct simplify_type<const ilist_iterator<NodeTy> > { |
| typedef NodeTy* SimpleType; |
| |
| static SimpleType getSimplifiedValue(const ilist_iterator<NodeTy> &Node) { |
| return &*Node; |
| } |
| }; |
| |
| |
| //===----------------------------------------------------------------------===// |
| // |
| /// iplist - The subset of list functionality that can safely be used on nodes |
| /// of polymorphic types, i.e. a heterogenous list with a common base class that |
| /// holds the next/prev pointers. The only state of the list itself is a single |
| /// pointer to the head of the list. |
| /// |
| /// This list can be in one of three interesting states: |
| /// 1. The list may be completely unconstructed. In this case, the head |
| /// pointer is null. When in this form, any query for an iterator (e.g. |
| /// begin() or end()) causes the list to transparently change to state #2. |
| /// 2. The list may be empty, but contain a sentinal for the end iterator. This |
| /// sentinal is created by the Traits::createSentinel method and is a link |
| /// in the list. When the list is empty, the pointer in the iplist points |
| /// to the sentinal. Once the sentinal is constructed, it |
| /// is not destroyed until the list is. |
| /// 3. The list may contain actual objects in it, which are stored as a doubly |
| /// linked list of nodes. One invariant of the list is that the predecessor |
| /// of the first node in the list always points to the last node in the list, |
| /// and the successor pointer for the sentinal (which always stays at the |
| /// end of the list) is always null. |
| /// |
| template<typename NodeTy, typename Traits=ilist_traits<NodeTy> > |
| class iplist : public Traits { |
| mutable NodeTy *Head; |
| |
| // Use the prev node pointer of 'head' as the tail pointer. This is really a |
| // circularly linked list where we snip the 'next' link from the sentinel node |
| // back to the first node in the list (to preserve assertions about going off |
| // the end of the list). |
| NodeTy *getTail() { return getPrev(Head); } |
| const NodeTy *getTail() const { return getPrev(Head); } |
| void setTail(NodeTy *N) const { setPrev(Head, N); } |
| |
| /// CreateLazySentinal - This method verifies whether the sentinal for the |
| /// list has been created and lazily makes it if not. |
| void CreateLazySentinal() const { |
| if (Head != 0) return; |
| Head = Traits::createSentinel(); |
| setNext(Head, 0); |
| setTail(Head); |
| } |
| |
| static bool op_less(NodeTy &L, NodeTy &R) { return L < R; } |
| static bool op_equal(NodeTy &L, NodeTy &R) { return L == R; } |
| public: |
| typedef NodeTy *pointer; |
| typedef const NodeTy *const_pointer; |
| typedef NodeTy &reference; |
| typedef const NodeTy &const_reference; |
| typedef NodeTy value_type; |
| typedef ilist_iterator<NodeTy> iterator; |
| typedef ilist_iterator<const NodeTy> const_iterator; |
| typedef size_t size_type; |
| typedef ptrdiff_t difference_type; |
| typedef std::reverse_iterator<const_iterator> const_reverse_iterator; |
| typedef std::reverse_iterator<iterator> reverse_iterator; |
| |
| iplist() : Head(0) {} |
| ~iplist() { |
| if (!Head) return; |
| clear(); |
| Traits::destroySentinel(getTail()); |
| } |
| |
| // Iterator creation methods. |
| iterator begin() { |
| CreateLazySentinal(); |
| return iterator(Head); |
| } |
| const_iterator begin() const { |
| CreateLazySentinal(); |
| return const_iterator(Head); |
| } |
| iterator end() { |
| CreateLazySentinal(); |
| return iterator(getTail()); |
| } |
| const_iterator end() const { |
| CreateLazySentinal(); |
| return const_iterator(getTail()); |
| } |
| |
| // reverse iterator creation methods. |
| reverse_iterator rbegin() { return reverse_iterator(end()); } |
| const_reverse_iterator rbegin() const{ return const_reverse_iterator(end()); } |
| reverse_iterator rend() { return reverse_iterator(begin()); } |
| const_reverse_iterator rend() const { return const_reverse_iterator(begin());} |
| |
| |
| // Miscellaneous inspection routines. |
| size_type max_size() const { return size_type(-1); } |
| bool empty() const { return Head == 0 || Head == getTail(); } |
| |
| // Front and back accessor functions... |
| reference front() { |
| assert(!empty() && "Called front() on empty list!"); |
| return *Head; |
| } |
| const_reference front() const { |
| assert(!empty() && "Called front() on empty list!"); |
| return *Head; |
| } |
| reference back() { |
| assert(!empty() && "Called back() on empty list!"); |
| return *getPrev(getTail()); |
| } |
| const_reference back() const { |
| assert(!empty() && "Called back() on empty list!"); |
| return *getPrev(getTail()); |
| } |
| |
| void swap(iplist &RHS) { |
| abort(); // Swap does not use list traits callback correctly yet! |
| std::swap(Head, RHS.Head); |
| } |
| |
| iterator insert(iterator where, NodeTy *New) { |
| NodeTy *CurNode = where.getNodePtrUnchecked(), *PrevNode = getPrev(CurNode); |
| setNext(New, CurNode); |
| setPrev(New, PrevNode); |
| |
| if (CurNode != Head) // Is PrevNode off the beginning of the list? |
| setNext(PrevNode, New); |
| else |
| Head = New; |
| setPrev(CurNode, New); |
| |
| addNodeToList(New); // Notify traits that we added a node... |
| return New; |
| } |
| |
| NodeTy *remove(iterator &IT) { |
| assert(IT != end() && "Cannot remove end of list!"); |
| NodeTy *Node = &*IT; |
| NodeTy *NextNode = getNext(Node); |
| NodeTy *PrevNode = getPrev(Node); |
| |
| if (Node != Head) // Is PrevNode off the beginning of the list? |
| setNext(PrevNode, NextNode); |
| else |
| Head = NextNode; |
| setPrev(NextNode, PrevNode); |
| IT = NextNode; |
| removeNodeFromList(Node); // Notify traits that we removed a node... |
| return Node; |
| } |
| |
| NodeTy *remove(const iterator &IT) { |
| iterator MutIt = IT; |
| return remove(MutIt); |
| } |
| |
| // erase - remove a node from the controlled sequence... and delete it. |
| iterator erase(iterator where) { |
| delete remove(where); |
| return where; |
| } |
| |
| |
| private: |
| // transfer - The heart of the splice function. Move linked list nodes from |
| // [first, last) into position. |
| // |
| void transfer(iterator position, iplist &L2, iterator first, iterator last) { |
| assert(first != last && "Should be checked by callers"); |
| |
| if (position != last) { |
| // Note: we have to be careful about the case when we move the first node |
| // in the list. This node is the list sentinel node and we can't move it. |
| NodeTy *ThisSentinel = getTail(); |
| setTail(0); |
| NodeTy *L2Sentinel = L2.getTail(); |
| L2.setTail(0); |
| |
| // Remove [first, last) from its old position. |
| NodeTy *First = &*first, *Prev = getPrev(First); |
| NodeTy *Next = last.getNodePtrUnchecked(), *Last = getPrev(Next); |
| if (Prev) |
| setNext(Prev, Next); |
| else |
| L2.Head = Next; |
| setPrev(Next, Prev); |
| |
| // Splice [first, last) into its new position. |
| NodeTy *PosNext = position.getNodePtrUnchecked(); |
| NodeTy *PosPrev = getPrev(PosNext); |
| |
| // Fix head of list... |
| if (PosPrev) |
| setNext(PosPrev, First); |
| else |
| Head = First; |
| setPrev(First, PosPrev); |
| |
| // Fix end of list... |
| setNext(Last, PosNext); |
| setPrev(PosNext, Last); |
| |
| transferNodesFromList(L2, First, PosNext); |
| |
| // Now that everything is set, restore the pointers to the list sentinals. |
| L2.setTail(L2Sentinel); |
| setTail(ThisSentinel); |
| } |
| } |
| |
| public: |
| |
| //===----------------------------------------------------------------------=== |
| // Functionality derived from other functions defined above... |
| // |
| |
| size_type size() const { |
| if (Head == 0) return 0; // Don't require construction of sentinal if empty. |
| #if __GNUC__ == 2 |
| // GCC 2.95 has a broken std::distance |
| size_type Result = 0; |
| std::distance(begin(), end(), Result); |
| return Result; |
| #else |
| return std::distance(begin(), end()); |
| #endif |
| } |
| |
| iterator erase(iterator first, iterator last) { |
| while (first != last) |
| first = erase(first); |
| return last; |
| } |
| |
| void clear() { if (Head) erase(begin(), end()); } |
| |
| // Front and back inserters... |
| void push_front(NodeTy *val) { insert(begin(), val); } |
| void push_back(NodeTy *val) { insert(end(), val); } |
| void pop_front() { |
| assert(!empty() && "pop_front() on empty list!"); |
| erase(begin()); |
| } |
| void pop_back() { |
| assert(!empty() && "pop_back() on empty list!"); |
| iterator t = end(); erase(--t); |
| } |
| |
| // Special forms of insert... |
| template<class InIt> void insert(iterator where, InIt first, InIt last) { |
| for (; first != last; ++first) insert(where, *first); |
| } |
| |
| // Splice members - defined in terms of transfer... |
| void splice(iterator where, iplist &L2) { |
| if (!L2.empty()) |
| transfer(where, L2, L2.begin(), L2.end()); |
| } |
| void splice(iterator where, iplist &L2, iterator first) { |
| iterator last = first; ++last; |
| if (where == first || where == last) return; // No change |
| transfer(where, L2, first, last); |
| } |
| void splice(iterator where, iplist &L2, iterator first, iterator last) { |
| if (first != last) transfer(where, L2, first, last); |
| } |
| |
| |
| |
| //===----------------------------------------------------------------------=== |
| // High-Level Functionality that shouldn't really be here, but is part of list |
| // |
| |
| // These two functions are actually called remove/remove_if in list<>, but |
| // they actually do the job of erase, rename them accordingly. |
| // |
| void erase(const NodeTy &val) { |
| for (iterator I = begin(), E = end(); I != E; ) { |
| iterator next = I; ++next; |
| if (*I == val) erase(I); |
| I = next; |
| } |
| } |
| template<class Pr1> void erase_if(Pr1 pred) { |
| for (iterator I = begin(), E = end(); I != E; ) { |
| iterator next = I; ++next; |
| if (pred(*I)) erase(I); |
| I = next; |
| } |
| } |
| |
| template<class Pr2> void unique(Pr2 pred) { |
| if (empty()) return; |
| for (iterator I = begin(), E = end(), Next = begin(); ++Next != E;) { |
| if (pred(*I)) |
| erase(Next); |
| else |
| I = Next; |
| Next = I; |
| } |
| } |
| void unique() { unique(op_equal); } |
| |
| template<class Pr3> void merge(iplist &right, Pr3 pred) { |
| iterator first1 = begin(), last1 = end(); |
| iterator first2 = right.begin(), last2 = right.end(); |
| while (first1 != last1 && first2 != last2) |
| if (pred(*first2, *first1)) { |
| iterator next = first2; |
| transfer(first1, right, first2, ++next); |
| first2 = next; |
| } else { |
| ++first1; |
| } |
| if (first2 != last2) transfer(last1, right, first2, last2); |
| } |
| void merge(iplist &right) { return merge(right, op_less); } |
| |
| template<class Pr3> void sort(Pr3 pred); |
| void sort() { sort(op_less); } |
| void reverse(); |
| }; |
| |
| |
| template<typename NodeTy> |
| struct ilist : public iplist<NodeTy> { |
| typedef typename iplist<NodeTy>::size_type size_type; |
| typedef typename iplist<NodeTy>::iterator iterator; |
| |
| ilist() {} |
| ilist(const ilist &right) { |
| insert(this->begin(), right.begin(), right.end()); |
| } |
| explicit ilist(size_type count) { |
| insert(this->begin(), count, NodeTy()); |
| } |
| ilist(size_type count, const NodeTy &val) { |
| insert(this->begin(), count, val); |
| } |
| template<class InIt> ilist(InIt first, InIt last) { |
| insert(this->begin(), first, last); |
| } |
| |
| |
| // Forwarding functions: A workaround for GCC 2.95 which does not correctly |
| // support 'using' declarations to bring a hidden member into scope. |
| // |
| iterator insert(iterator a, NodeTy *b){ return iplist<NodeTy>::insert(a, b); } |
| void push_front(NodeTy *a) { iplist<NodeTy>::push_front(a); } |
| void push_back(NodeTy *a) { iplist<NodeTy>::push_back(a); } |
| |
| |
| // Main implementation here - Insert for a node passed by value... |
| iterator insert(iterator where, const NodeTy &val) { |
| return insert(where, createNode(val)); |
| } |
| |
| |
| // Front and back inserters... |
| void push_front(const NodeTy &val) { insert(this->begin(), val); } |
| void push_back(const NodeTy &val) { insert(this->end(), val); } |
| |
| // Special forms of insert... |
| template<class InIt> void insert(iterator where, InIt first, InIt last) { |
| for (; first != last; ++first) insert(where, *first); |
| } |
| void insert(iterator where, size_type count, const NodeTy &val) { |
| for (; count != 0; --count) insert(where, val); |
| } |
| |
| // Assign special forms... |
| void assign(size_type count, const NodeTy &val) { |
| iterator I = this->begin(); |
| for (; I != this->end() && count != 0; ++I, --count) |
| *I = val; |
| if (count != 0) |
| insert(this->end(), val, val); |
| else |
| erase(I, this->end()); |
| } |
| template<class InIt> void assign(InIt first1, InIt last1) { |
| iterator first2 = this->begin(), last2 = this->end(); |
| for ( ; first1 != last1 && first2 != last2; ++first1, ++first2) |
| *first1 = *first2; |
| if (first2 == last2) |
| erase(first1, last1); |
| else |
| insert(last1, first2, last2); |
| } |
| |
| |
| // Resize members... |
| void resize(size_type newsize, NodeTy val) { |
| iterator i = this->begin(); |
| size_type len = 0; |
| for ( ; i != this->end() && len < newsize; ++i, ++len) /* empty*/ ; |
| |
| if (len == newsize) |
| erase(i, this->end()); |
| else // i == end() |
| insert(this->end(), newsize - len, val); |
| } |
| void resize(size_type newsize) { resize(newsize, NodeTy()); } |
| }; |
| |
| } // End llvm namespace |
| |
| namespace std { |
| // Ensure that swap uses the fast list swap... |
| template<class Ty> |
| void swap(llvm::iplist<Ty> &Left, llvm::iplist<Ty> &Right) { |
| Left.swap(Right); |
| } |
| } // End 'std' extensions... |
| |
| #endif |