X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FADT%2Filist.h;h=8c19a6f4547a72895a8bca980865f7fbd7498993;hb=af628cc0b84d3f6acfb2a8dab696b93945e73e88;hp=42d09c7b4500804fddc7190cdf3981c320d0fa9c;hpb=d68a07650cdb2e18f18f362ba533459aa10e01b6;p=oota-llvm.git diff --git a/include/llvm/ADT/ilist.h b/include/llvm/ADT/ilist.h index 42d09c7b450..8c19a6f4547 100644 --- a/include/llvm/ADT/ilist.h +++ b/include/llvm/ADT/ilist.h @@ -1,10 +1,10 @@ //==-- llvm/ADT/ilist.h - 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 @@ -38,8 +38,11 @@ #ifndef LLVM_ADT_ILIST_H #define LLVM_ADT_ILIST_H -#include "llvm/ADT/iterator.h" +#include "llvm/Support/Compiler.h" +#include #include +#include +#include namespace llvm { @@ -60,36 +63,76 @@ struct ilist_nextprev_traits { static void setNext(NodeTy *N, NodeTy *Next) { N->setNext(Next); } }; +template +struct ilist_traits; + /// ilist_sentinel_traits - A fragment for template traits for intrusive list /// that provides default sentinel implementations for common operations. /// +/// ilist_sentinel_traits implements a lazy dynamic sentinel allocation +/// strategy. The sentinel is stored in the prev field of ilist's Head. +/// template struct ilist_sentinel_traits { + /// createSentinel - create the dynamic sentinel static NodeTy *createSentinel() { return new NodeTy(); } + + /// destroySentinel - deallocate the dynamic sentinel static void destroySentinel(NodeTy *N) { delete N; } + + /// provideInitialHead - when constructing an ilist, provide a starting + /// value for its Head + /// @return null node to indicate that it needs to be allocated later + static NodeTy *provideInitialHead() { return nullptr; } + + /// ensureHead - make sure that Head is either already + /// initialized or assigned a fresh sentinel + /// @return the sentinel + static NodeTy *ensureHead(NodeTy *&Head) { + if (!Head) { + Head = ilist_traits::createSentinel(); + ilist_traits::noteHead(Head, Head); + ilist_traits::setNext(Head, nullptr); + return Head; + } + return ilist_traits::getPrev(Head); + } + + /// noteHead - stash the sentinel into its default location + static void noteHead(NodeTy *NewHead, NodeTy *Sentinel) { + ilist_traits::setPrev(NewHead, Sentinel); + } }; -/// ilist_default_traits - Default template traits for intrusive list. -/// By inheriting from this, you can easily use default implementations -/// for all common operations. +/// ilist_node_traits - A fragment for template traits for intrusive list +/// that provides default node related operations. /// template -struct ilist_default_traits : ilist_nextprev_traits, - ilist_sentinel_traits { +struct ilist_node_traits { static NodeTy *createNode(const NodeTy &V) { return new NodeTy(V); } static void deleteNode(NodeTy *V) { delete V; } void addNodeToList(NodeTy *) {} void removeNodeFromList(NodeTy *) {} - void transferNodesFromList(ilist_default_traits & /*SrcTraits*/, + void transferNodesFromList(ilist_node_traits & /*SrcTraits*/, ilist_iterator /*first*/, ilist_iterator /*last*/) {} }; +/// ilist_default_traits - Default template traits for intrusive list. +/// By inheriting from this, you can easily use default implementations +/// for all common operations. +/// +template +struct ilist_default_traits : public ilist_nextprev_traits, + public ilist_sentinel_traits, + public ilist_node_traits { +}; + // Template traits for intrusive list. By specializing this template class, you // can change what next/prev fields are used to store the links... template -struct ilist_traits : ilist_default_traits {}; +struct ilist_traits : public ilist_default_traits {}; // Const traits are the same as nonconst traits... template @@ -100,11 +143,12 @@ struct ilist_traits : public ilist_traits {}; // template class ilist_iterator - : public bidirectional_iterator { - + : public std::iterator { + public: typedef ilist_traits Traits; - typedef bidirectional_iterator super; + typedef std::iterator super; typedef typename super::value_type value_type; typedef typename super::difference_type difference_type; @@ -131,7 +175,7 @@ public: ilist_iterator(pointer NP) : NodePtr(NP) {} ilist_iterator(reference NR) : NodePtr(&NR) {} - ilist_iterator() : NodePtr(0) {} + ilist_iterator() : NodePtr(nullptr) {} // This is templated so that we can allow constructing a const iterator from // a nonconst iterator... @@ -149,12 +193,10 @@ public: // 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->() const { return &operator*(); } @@ -170,12 +212,11 @@ public: // 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!"); + assert(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... @@ -193,17 +234,17 @@ public: pointer getNodePtrUnchecked() const { return NodePtr; } }; -// do not implement. this is to catch errors when people try to use -// them as random access iterators +// These are to catch errors when people try to use them as random access +// iterators. template -void operator-(int, ilist_iterator); +void operator-(int, ilist_iterator) LLVM_DELETED_FUNCTION; template -void operator-(ilist_iterator,int); +void operator-(ilist_iterator,int) LLVM_DELETED_FUNCTION; template -void operator+(int, ilist_iterator); +void operator+(int, ilist_iterator) LLVM_DELETED_FUNCTION; template -void operator+(ilist_iterator,int); +void operator+(ilist_iterator,int) LLVM_DELETED_FUNCTION; // operator!=/operator== - Allow mixed comparisons without dereferencing // the iterator, which could very likely be pointing to end(). @@ -232,14 +273,14 @@ template struct simplify_type; template struct simplify_type > { typedef NodeTy* SimpleType; - - static SimpleType getSimplifiedValue(const ilist_iterator &Node) { + + static SimpleType getSimplifiedValue(ilist_iterator &Node) { return &*Node; } }; template struct simplify_type > { - typedef NodeTy* SimpleType; - + typedef /*const*/ NodeTy* SimpleType; + static SimpleType getSimplifiedValue(const ilist_iterator &Node) { return &*Node; } @@ -249,7 +290,7 @@ template struct simplify_type > { //===----------------------------------------------------------------------===// // /// 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 +/// of polymorphic types, i.e. a heterogeneous 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. /// @@ -257,16 +298,16 @@ template struct simplify_type > { /// 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 +/// 2. The list may be empty, but contain a sentinel for the end iterator. This +/// sentinel 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 +/// to the sentinel. Once the sentinel 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. +/// and the successor pointer for the sentinel (which always stays at the +/// end of the list) is always null. /// template > class iplist : public Traits { @@ -276,26 +317,23 @@ class iplist : public Traits { // 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 this->getPrev(Head); } - const NodeTy *getTail() const { return this->getPrev(Head); } - void setTail(NodeTy *N) const { this->setPrev(Head, N); } - - /// CreateLazySentinal - This method verifies whether the sentinal for the + NodeTy *getTail() { return this->ensureHead(Head); } + const NodeTy *getTail() const { return this->ensureHead(Head); } + void setTail(NodeTy *N) const { this->noteHead(Head, N); } + + /// CreateLazySentinel - This method verifies whether the sentinel for the /// list has been created and lazily makes it if not. - void CreateLazySentinal() const { - if (Head != 0) return; - Head = Traits::createSentinel(); - this->setNext(Head, 0); - setTail(Head); + void CreateLazySentinel() const { + this->ensureHead(Head); } static bool op_less(NodeTy &L, NodeTy &R) { return L < R; } static bool op_equal(NodeTy &L, NodeTy &R) { return L == R; } - // No fundamental reason why iplist can't by copyable, but the default + // No fundamental reason why iplist can't be copyable, but the default // copy/copy-assign won't do. - iplist(const iplist &); // do not implement - void operator=(const iplist &); // do not implement + iplist(const iplist &) LLVM_DELETED_FUNCTION; + void operator=(const iplist &) LLVM_DELETED_FUNCTION; public: typedef NodeTy *pointer; @@ -310,7 +348,7 @@ public: typedef std::reverse_iterator const_reverse_iterator; typedef std::reverse_iterator reverse_iterator; - iplist() : Head(0) {} + iplist() : Head(this->provideInitialHead()) {} ~iplist() { if (!Head) return; clear(); @@ -319,19 +357,19 @@ public: // Iterator creation methods. iterator begin() { - CreateLazySentinal(); - return iterator(Head); + CreateLazySentinel(); + return iterator(Head); } const_iterator begin() const { - CreateLazySentinal(); + CreateLazySentinel(); return const_iterator(Head); } iterator end() { - CreateLazySentinal(); + CreateLazySentinel(); return iterator(getTail()); } const_iterator end() const { - CreateLazySentinal(); + CreateLazySentinel(); return const_iterator(getTail()); } @@ -344,7 +382,9 @@ public: // Miscellaneous inspection routines. size_type max_size() const { return size_type(-1); } - bool empty() const { return Head == 0 || Head == getTail(); } + bool LLVM_ATTRIBUTE_UNUSED_RESULT empty() const { + return !Head || Head == getTail(); + } // Front and back accessor functions... reference front() { @@ -370,7 +410,8 @@ public: } iterator insert(iterator where, NodeTy *New) { - NodeTy *CurNode = where.getNodePtrUnchecked(), *PrevNode = this->getPrev(CurNode); + NodeTy *CurNode = where.getNodePtrUnchecked(); + NodeTy *PrevNode = this->getPrev(CurNode); this->setNext(New, CurNode); this->setPrev(New, PrevNode); @@ -384,6 +425,13 @@ public: return New; } + iterator insertAfter(iterator where, NodeTy *New) { + if (empty()) + return insert(begin(), New); + else + return insert(++where, New); + } + NodeTy *remove(iterator &IT) { assert(IT != end() && "Cannot remove end of list!"); NodeTy *Node = &*IT; @@ -396,15 +444,15 @@ public: Head = NextNode; this->setPrev(NextNode, PrevNode); IT = NextNode; - removeNodeFromList(Node); // Notify traits that we removed a node... - + this->removeNodeFromList(Node); // Notify traits that we removed a node... + // Set the next/prev pointers of the current node to null. This isn't // strictly required, but this catches errors where a node is removed from // an ilist (and potentially deleted) with iterators still pointing at it. // When those iterators are incremented or decremented, they will assert on // the null next/prev pointer instead of "usually working". - this->setNext(Node, 0); - this->setPrev(Node, 0); + this->setNext(Node, nullptr); + this->setPrev(Node, nullptr); return Node; } @@ -415,10 +463,21 @@ public: // erase - remove a node from the controlled sequence... and delete it. iterator erase(iterator where) { - deleteNode(remove(where)); + this->deleteNode(remove(where)); return where; } + /// Remove all nodes from the list like clear(), but do not call + /// removeNodeFromList() or deleteNode(). + /// + /// This should only be used immediately before freeing nodes in bulk to + /// avoid traversing the list and bringing all the nodes into cache. + void clearAndLeakNodesUnsafely() { + if (Head) { + Head = getTail(); + this->setPrev(Head, Head); + } + } private: // transfer - The heart of the splice function. Move linked list nodes from @@ -426,18 +485,22 @@ private: // void transfer(iterator position, iplist &L2, iterator first, iterator last) { assert(first != last && "Should be checked by callers"); + // Position cannot be contained in the range to be transferred. + // Check for the most common mistake. + assert(position != first && + "Insertion point can't be one of the transferred nodes"); 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); + setTail(nullptr); NodeTy *L2Sentinel = L2.getTail(); - L2.setTail(0); + L2.setTail(nullptr); // Remove [first, last) from its old position. - NodeTy *First = &*first, *Prev = getPrev(First); - NodeTy *Next = last.getNodePtrUnchecked(), *Last = getPrev(Next); + NodeTy *First = &*first, *Prev = this->getPrev(First); + NodeTy *Next = last.getNodePtrUnchecked(), *Last = this->getPrev(Next); if (Prev) this->setNext(Prev, Next); else @@ -446,7 +509,7 @@ private: // Splice [first, last) into its new position. NodeTy *PosNext = position.getNodePtrUnchecked(); - NodeTy *PosPrev = getPrev(PosNext); + NodeTy *PosPrev = this->getPrev(PosNext); // Fix head of list... if (PosPrev) @@ -459,9 +522,9 @@ private: this->setNext(Last, PosNext); this->setPrev(PosNext, Last); - transferNodesFromList(L2, First, PosNext); + this->transferNodesFromList(L2, First, PosNext); - // Now that everything is set, restore the pointers to the list sentinals. + // Now that everything is set, restore the pointers to the list sentinels. L2.setTail(L2Sentinel); setTail(ThisSentinel); } @@ -473,16 +536,9 @@ 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 + size_type LLVM_ATTRIBUTE_UNUSED_RESULT size() const { + if (!Head) return 0; // Don't require construction of sentinel if empty. return std::distance(begin(), end()); -#endif } iterator erase(iterator first, iterator last) { @@ -523,61 +579,6 @@ public: 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 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 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 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 void sort(Pr3 pred); - void sort() { sort(op_less); } - void reverse(); }; @@ -592,7 +593,7 @@ struct ilist : public iplist { } explicit ilist(size_type count) { insert(this->begin(), count, NodeTy()); - } + } ilist(size_type count, const NodeTy &val) { insert(this->begin(), count, val); } @@ -600,18 +601,14 @@ struct ilist : public iplist { 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::insert(a, b); } - void push_front(NodeTy *a) { iplist::push_front(a); } - void push_back(NodeTy *a) { iplist::push_back(a); } - + // bring hidden functions into scope + using iplist::insert; + using iplist::push_front; + using iplist::push_back; // Main implementation here - Insert for a node passed by value... iterator insert(iterator where, const NodeTy &val) { - return insert(where, createNode(val)); + return insert(where, this->createNode(val)); } @@ -619,10 +616,6 @@ struct ilist : public iplist { 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 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); }