llvm-6502/include/llvm/ADT/ilist_node.h

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//==-- llvm/ADT/ilist_node.h - Intrusive Linked List Helper ------*- 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 the ilist_node class template, which is a convenient
// base class for creating classes that can be used with ilists.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_ADT_ILISTNODE_H
#define LLVM_ADT_ILISTNODE_H
namespace llvm {
template<typename NodeTy>
struct ilist_traits;
/// ilist_half_node - Base class that provides prev services for sentinels.
///
template<typename NodeTy>
class ilist_half_node {
friend struct ilist_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;
/// 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 ilist_half_node<NodeTy> {
friend struct ilist_nextprev_traits<NodeTy>;
friend struct ilist_traits<NodeTy>;
NodeTy *Next;
NodeTy *getNext() { return Next; }
const NodeTy *getNext() const { return Next; }
void setNext(NodeTy *N) { Next = N; }
protected:
ilist_node() : Next(nullptr) {}
public:
/// @name Adjacent Node Accessors
/// @{
/// \brief Get the previous node, or 0 for the list head.
NodeTy *getPrevNode() {
NodeTy *Prev = this->getPrev();
// Check for sentinel.
if (!Prev->getNext())
return nullptr;
return Prev;
}
/// \brief Get the previous node, or 0 for the list head.
const NodeTy *getPrevNode() const {
const NodeTy *Prev = this->getPrev();
// Check for sentinel.
if (!Prev->getNext())
return nullptr;
return Prev;
}
/// \brief Get the next node, or 0 for the list tail.
NodeTy *getNextNode() {
NodeTy *Next = getNext();
// Check for sentinel.
if (!Next->getNext())
return nullptr;
return Next;
}
/// \brief Get the next node, or 0 for the list tail.
const NodeTy *getNextNode() const {
const NodeTy *Next = getNext();
// Check for sentinel.
if (!Next->getNext())
return nullptr;
return Next;
}
/// @}
};
} // End llvm namespace
#endif