namespace llvm {
template<typename NodeTy>
-struct ilist_nextprev_traits;
+struct ilist_traits;
+template <typename NodeTy> struct ilist_embedded_sentinel_traits;
+template <typename NodeTy> struct ilist_half_embedded_sentinel_traits;
+/// ilist_half_node - Base class that provides prev services for sentinels.
+///
template<typename NodeTy>
-struct ilist_traits;
+class ilist_half_node {
+ friend struct ilist_traits<NodeTy>;
+ friend struct ilist_half_embedded_sentinel_traits<NodeTy>;
+ NodeTy *Prev;
+protected:
+ NodeTy *getPrev() { return Prev; }
+ const NodeTy *getPrev() const { return Prev; }
+ void setPrev(NodeTy *P) { Prev = P; }
+ ilist_half_node() : Prev(nullptr) {}
+};
+
+template<typename NodeTy>
+struct ilist_nextprev_traits;
+
+template <typename NodeTy> class ilist_iterator;
/// ilist_node - Base class that provides next/prev services for nodes
/// that use ilist_nextprev_traits or ilist_default_traits.
///
template<typename NodeTy>
-class ilist_node {
-private:
+class ilist_node : private ilist_half_node<NodeTy> {
friend struct ilist_nextprev_traits<NodeTy>;
friend struct ilist_traits<NodeTy>;
- NodeTy *Prev, *Next;
- NodeTy *getPrev() { return Prev; }
+ friend struct ilist_half_embedded_sentinel_traits<NodeTy>;
+ friend struct ilist_embedded_sentinel_traits<NodeTy>;
+ NodeTy *Next;
NodeTy *getNext() { return Next; }
- const NodeTy *getPrev() const { return Prev; }
const NodeTy *getNext() const { return Next; }
- void setPrev(NodeTy *N) { Prev = N; }
void setNext(NodeTy *N) { Next = N; }
protected:
- ilist_node() : Prev(0), Next(0) {}
+ ilist_node() : Next(nullptr) {}
+
+public:
+ ilist_iterator<NodeTy> getIterator() {
+ // FIXME: Stop downcasting to create the iterator (potential UB).
+ return ilist_iterator<NodeTy>(static_cast<NodeTy *>(this));
+ }
+ ilist_iterator<const NodeTy> getIterator() const {
+ // FIXME: Stop downcasting to create the iterator (potential UB).
+ return ilist_iterator<const NodeTy>(static_cast<const NodeTy *>(this));
+ }
+};
+
+/// An ilist node that can access its parent list.
+///
+/// Requires \c NodeTy to have \a getParent() to find the parent node, and the
+/// \c ParentTy to have \a getSublistAccess() to get a reference to the list.
+template <typename NodeTy, typename ParentTy>
+class ilist_node_with_parent : public ilist_node<NodeTy> {
+protected:
+ ilist_node_with_parent() = default;
+
+private:
+ /// Forward to NodeTy::getParent().
+ ///
+ /// Note: do not use the name "getParent()". We want a compile error
+ /// (instead of recursion) when the subclass fails to implement \a
+ /// getParent().
+ const ParentTy *getNodeParent() const {
+ return static_cast<const NodeTy *>(this)->getParent();
+ }
+
+public:
+ /// @name Adjacent Node Accessors
+ /// @{
+ /// \brief Get the previous node, or \c nullptr for the list head.
+ NodeTy *getPrevNode() {
+ // Should be separated to a reused function, but then we couldn't use auto
+ // (and would need the type of the list).
+ const auto &List =
+ getNodeParent()->*(ParentTy::getSublistAccess((NodeTy *)nullptr));
+ return List.getPrevNode(*static_cast<NodeTy *>(this));
+ }
+ /// \brief Get the previous node, or \c nullptr for the list head.
+ const NodeTy *getPrevNode() const {
+ return const_cast<ilist_node_with_parent *>(this)->getPrevNode();
+ }
+
+ /// \brief Get the next node, or \c nullptr for the list tail.
+ NodeTy *getNextNode() {
+ // Should be separated to a reused function, but then we couldn't use auto
+ // (and would need the type of the list).
+ const auto &List =
+ getNodeParent()->*(ParentTy::getSublistAccess((NodeTy *)nullptr));
+ return List.getNextNode(*static_cast<NodeTy *>(this));
+ }
+ /// \brief Get the next node, or \c nullptr for the list tail.
+ const NodeTy *getNextNode() const {
+ return const_cast<ilist_node_with_parent *>(this)->getNextNode();
+ }
+ /// @}
};
} // End llvm namespace