X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FADT%2Filist.h;h=3044a6c435f104e64df191b7a2e8e74680a718c0;hb=44fb5881d8edf448d6231a5b8df583aecd6bcd42;hp=51442e35630acd63fca7ab07d022c8973b4805e4;hpb=c23b8719ef9d6b1220e854b37d40e9e1c48a82bc;p=oota-llvm.git diff --git a/include/llvm/ADT/ilist.h b/include/llvm/ADT/ilist.h index 51442e35630..3044a6c435f 100644 --- a/include/llvm/ADT/ilist.h +++ b/include/llvm/ADT/ilist.h @@ -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 { @@ -80,7 +83,7 @@ struct ilist_sentinel_traits { /// 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 0; } + static NodeTy *provideInitialHead() { return nullptr; } /// ensureHead - make sure that Head is either already /// initialized or assigned a fresh sentinel @@ -89,7 +92,7 @@ struct ilist_sentinel_traits { if (!Head) { Head = ilist_traits::createSentinel(); ilist_traits::noteHead(Head, Head); - ilist_traits::setNext(Head, 0); + ilist_traits::setNext(Head, nullptr); return Head; } return ilist_traits::getPrev(Head); @@ -101,6 +104,53 @@ struct ilist_sentinel_traits { } }; +template class ilist_half_node; +template class ilist_node; + +/// Traits with an embedded ilist_node as a sentinel. +/// +/// FIXME: The downcast in createSentinel() is UB. +template struct ilist_embedded_sentinel_traits { + /// Get hold of the node that marks the end of the list. + NodeTy *createSentinel() const { + // Since i(p)lists always publicly derive from their corresponding traits, + // placing a data member in this class will augment the i(p)list. But since + // the NodeTy is expected to be publicly derive from ilist_node, + // there is a legal viable downcast from it to NodeTy. We use this trick to + // superimpose an i(p)list with a "ghostly" NodeTy, which becomes the + // sentinel. Dereferencing the sentinel is forbidden (save the + // ilist_node), so no one will ever notice the superposition. + return static_cast(&Sentinel); + } + static void destroySentinel(NodeTy *) {} + + NodeTy *provideInitialHead() const { return createSentinel(); } + NodeTy *ensureHead(NodeTy *) const { return createSentinel(); } + static void noteHead(NodeTy *, NodeTy *) {} + +private: + mutable ilist_node Sentinel; +}; + +/// Trait with an embedded ilist_half_node as a sentinel. +/// +/// FIXME: The downcast in createSentinel() is UB. +template struct ilist_half_embedded_sentinel_traits { + /// Get hold of the node that marks the end of the list. + NodeTy *createSentinel() const { + // See comment in ilist_embedded_sentinel_traits::createSentinel(). + return static_cast(&Sentinel); + } + static void destroySentinel(NodeTy *) {} + + NodeTy *provideInitialHead() const { return createSentinel(); } + NodeTy *ensureHead(NodeTy *) const { return createSentinel(); } + static void noteHead(NodeTy *, NodeTy *) {} + +private: + mutable ilist_half_node Sentinel; +}; + /// ilist_node_traits - A fragment for template traits for intrusive list /// that provides default node related operations. /// @@ -121,15 +171,15 @@ struct ilist_node_traits { /// for all common operations. /// template -struct ilist_default_traits : ilist_nextprev_traits, - ilist_sentinel_traits, - ilist_node_traits { +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 @@ -140,11 +190,12 @@ 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; @@ -169,9 +220,9 @@ private: template void operator-(T) const; public: - ilist_iterator(pointer NP) : NodePtr(NP) {} - ilist_iterator(reference NR) : NodePtr(&NR) {} - ilist_iterator() : NodePtr(0) {} + explicit ilist_iterator(pointer NP) : NodePtr(NP) {} + explicit ilist_iterator(reference NR) : NodePtr(&NR) {} + ilist_iterator() : NodePtr(nullptr) {} // This is templated so that we can allow constructing a const iterator from // a nonconst iterator... @@ -187,35 +238,34 @@ public: return *this; } + void reset(pointer NP) { NodePtr = NP; } + // Accessors... - operator pointer() const { - assert(Traits::getNext(NodePtr) != 0 && "Dereferencing end()!"); + explicit operator pointer() const { return NodePtr; } reference operator*() const { - assert(Traits::getNext(NodePtr) != 0 && "Dereferencing end()!"); return *NodePtr; } pointer operator->() const { return &operator*(); } // Comparison operators - bool operator==(const ilist_iterator &RHS) const { - return NodePtr == RHS.NodePtr; + template bool operator==(const ilist_iterator &RHS) const { + return NodePtr == RHS.getNodePtrUnchecked(); } - bool operator!=(const ilist_iterator &RHS) const { - return NodePtr != RHS.NodePtr; + template bool operator!=(const ilist_iterator &RHS) const { + return NodePtr != RHS.getNodePtrUnchecked(); } // 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... @@ -233,17 +283,17 @@ 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) = delete; template -void operator-(ilist_iterator,int); +void operator-(ilist_iterator,int) = delete; template -void operator+(int, ilist_iterator); +void operator+(int, ilist_iterator) = delete; template -void operator+(ilist_iterator,int); +void operator+(ilist_iterator,int) = delete; // operator!=/operator== - Allow mixed comparisons without dereferencing // the iterator, which could very likely be pointing to end(). @@ -273,12 +323,12 @@ 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; @@ -289,7 +339,7 @@ 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. /// @@ -323,16 +373,16 @@ class iplist : public Traits { /// CreateLazySentinel - This method verifies whether the sentinel for the /// list has been created and lazily makes it if not. void CreateLazySentinel() const { - this->Traits::ensureHead(Head); + 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 &) = delete; + void operator=(const iplist &) = delete; public: typedef NodeTy *pointer; @@ -347,7 +397,7 @@ public: typedef std::reverse_iterator const_reverse_iterator; typedef std::reverse_iterator reverse_iterator; - iplist() : Head(this->Traits::provideInitialHead()) {} + iplist() : Head(this->provideInitialHead()) {} ~iplist() { if (!Head) return; clear(); @@ -381,7 +431,9 @@ 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() { @@ -419,7 +471,7 @@ public: this->setPrev(CurNode, New); this->addNodeToList(New); // Notify traits that we added a node... - return New; + return iterator(New); } iterator insertAfter(iterator where, NodeTy *New) { @@ -440,7 +492,7 @@ public: else Head = NextNode; this->setPrev(NextNode, PrevNode); - IT = NextNode; + IT.reset(NextNode); this->removeNodeFromList(Node); // Notify traits that we removed a node... // Set the next/prev pointers of the current node to null. This isn't @@ -448,8 +500,8 @@ public: // 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; } @@ -458,12 +510,29 @@ public: return remove(MutIt); } + NodeTy *remove(NodeTy *IT) { return remove(iterator(IT)); } + NodeTy *remove(NodeTy &IT) { return remove(iterator(IT)); } + // erase - remove a node from the controlled sequence... and delete it. iterator erase(iterator where) { this->deleteNode(remove(where)); return where; } + iterator erase(NodeTy *IT) { return erase(iterator(IT)); } + iterator erase(NodeTy &IT) { return erase(iterator(IT)); } + + /// 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 @@ -471,18 +540,22 @@ 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 @@ -491,7 +564,7 @@ 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) @@ -504,7 +577,7 @@ private: this->setNext(Last, PosNext); this->setPrev(PosNext, Last); - transferNodesFromList(L2, First, PosNext); + this->transferNodesFromList(L2, iterator(First), iterator(PosNext)); // Now that everything is set, restore the pointers to the list sentinels. L2.setTail(L2Sentinel); @@ -518,8 +591,8 @@ public: // Functionality derived from other functions defined above... // - size_type size() const { - if (Head == 0) return 0; // Don't require construction of sentinel if empty. + 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()); } @@ -561,61 +634,83 @@ 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; - } + void splice(iterator where, iplist &L2, NodeTy &N) { + splice(where, L2, iterator(N)); + } + void splice(iterator where, iplist &L2, NodeTy *N) { + splice(where, L2, iterator(N)); } - 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 merge(iplist &Right, Compare comp) { + if (this == &Right) + return; + iterator First1 = begin(), Last1 = end(); + iterator First2 = Right.begin(), Last2 = Right.end(); + while (First1 != Last1 && First2 != Last2) { + if (comp(*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 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; + template + void sort(Compare comp) { + // The list is empty, vacuously sorted. + if (empty()) + return; + // The list has a single element, vacuously sorted. + if (std::next(begin()) == end()) + return; + // Find the split point for the list. + iterator Center = begin(), End = begin(); + while (End != end() && std::next(End) != end()) { + Center = std::next(Center); + End = std::next(std::next(End)); } + // Split the list into two. + iplist RightHalf; + RightHalf.splice(RightHalf.begin(), *this, Center, end()); + + // Sort the two sublists. + sort(comp); + RightHalf.sort(comp); + + // Merge the two sublists back together. + merge(RightHalf, comp); } - void unique() { unique(op_equal); } + void sort() { sort(op_less); } - 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); + /// \brief Get the previous node, or \c nullptr for the list head. + NodeTy *getPrevNode(NodeTy &N) const { + auto I = N.getIterator(); + if (I == begin()) + return nullptr; + return &*std::prev(I); + } + /// \brief Get the previous node, or \c nullptr for the list head. + const NodeTy *getPrevNode(const NodeTy &N) const { + return getPrevNode(const_cast(N)); } - void merge(iplist &right) { return merge(right, op_less); } - template void sort(Pr3 pred); - void sort() { sort(op_less); } - void reverse(); + /// \brief Get the next node, or \c nullptr for the list tail. + NodeTy *getNextNode(NodeTy &N) const { + auto Next = std::next(N.getIterator()); + if (Next == end()) + return nullptr; + return &*Next; + } + /// \brief Get the next node, or \c nullptr for the list tail. + const NodeTy *getNextNode(const NodeTy &N) const { + return getNextNode(const_cast(N)); + } }; @@ -645,7 +740,7 @@ struct ilist : public iplist { // 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)); } @@ -653,10 +748,6 @@ 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); }