| //===- llvm/ADT/ilist_node_base.h - Intrusive List Node Base -----*- C++ -*-==// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_ADT_ILIST_NODE_BASE_H |
| #define LLVM_ADT_ILIST_NODE_BASE_H |
| |
| #include "llvm/ADT/PointerIntPair.h" |
| |
| namespace llvm { |
| |
| /// Base class for ilist nodes. |
| /// |
| /// Optionally tracks whether this node is the sentinel. |
| template <bool EnableSentinelTracking> class ilist_node_base; |
| |
| template <> class ilist_node_base<false> { |
| ilist_node_base *Prev = nullptr; |
| ilist_node_base *Next = nullptr; |
| |
| public: |
| void setPrev(ilist_node_base *Prev) { this->Prev = Prev; } |
| void setNext(ilist_node_base *Next) { this->Next = Next; } |
| ilist_node_base *getPrev() const { return Prev; } |
| ilist_node_base *getNext() const { return Next; } |
| |
| bool isKnownSentinel() const { return false; } |
| void initializeSentinel() {} |
| }; |
| |
| template <> class ilist_node_base<true> { |
| PointerIntPair<ilist_node_base *, 1> PrevAndSentinel; |
| ilist_node_base *Next = nullptr; |
| |
| public: |
| void setPrev(ilist_node_base *Prev) { PrevAndSentinel.setPointer(Prev); } |
| void setNext(ilist_node_base *Next) { this->Next = Next; } |
| ilist_node_base *getPrev() const { return PrevAndSentinel.getPointer(); } |
| ilist_node_base *getNext() const { return Next; } |
| |
| bool isSentinel() const { return PrevAndSentinel.getInt(); } |
| bool isKnownSentinel() const { return isSentinel(); } |
| void initializeSentinel() { PrevAndSentinel.setInt(true); } |
| }; |
| |
| } // end namespace llvm |
| |
| #endif // LLVM_ADT_ILIST_NODE_BASE_H |