- void addNodeToList(NodeTy *NTy) {}
- void removeNodeFromList(NodeTy *NTy) {}
- void transferNodesFromList(iplist<NodeTy, ilist_traits> &L2,
- ilist_iterator<NodeTy> first,
- ilist_iterator<NodeTy> last) {}
+ /// 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; }
+
+ /// 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<NodeTy>::createSentinel();
+ ilist_traits<NodeTy>::noteHead(Head, Head);
+ ilist_traits<NodeTy>::setNext(Head, 0);
+ return Head;
+ }
+ return ilist_traits<NodeTy>::getPrev(Head);
+ }
+
+ /// noteHead - stash the sentinel into its default location
+ static void noteHead(NodeTy *NewHead, NodeTy *Sentinel) {
+ ilist_traits<NodeTy>::setPrev(NewHead, Sentinel);
+ }
+};
+
+/// ilist_node_traits - A fragment for template traits for intrusive list
+/// that provides default node related operations.
+///
+template<typename NodeTy>
+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_node_traits & /*SrcTraits*/,
+ ilist_iterator<NodeTy> /*first*/,
+ ilist_iterator<NodeTy> /*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<typename NodeTy>
+struct ilist_default_traits : public ilist_nextprev_traits<NodeTy>,
+ public ilist_sentinel_traits<NodeTy>,
+ public ilist_node_traits<NodeTy> {