1 //===- GCFactoryListTraits.h ----------------------------------------------===// 2 // 3 // The MCLinker Project 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 #ifndef MCLD_SUPPORT_GCFACTORYLISTTRAITS_H 10 #define MCLD_SUPPORT_GCFACTORYLISTTRAITS_H 11 12 #include <llvm/ADT/ilist_node.h> 13 #include <llvm/ADT/ilist.h> 14 15 #include <assert.h> 16 17 namespace mcld { 18 19 /** \class GCFactoryListTraits 20 * \brief GCFactoryListTraits provides trait class for llvm::iplist when 21 * the nodes in the list is produced by GCFactory. 22 */ 23 template<typename DataType> 24 class GCFactoryListTraits : public llvm::ilist_default_traits<DataType> 25 { 26 private: 27 class SentinelNode : public DataType 28 { 29 public: SentinelNode()30 SentinelNode() { } 31 }; 32 33 public: 34 // override the traits provided in llvm::ilist_sentinel_traits since we've 35 // defined our own sentinel. createSentinel()36 DataType *createSentinel() const 37 { return reinterpret_cast<DataType*>(&mSentinel); } 38 destroySentinel(DataType *)39 static void destroySentinel(DataType*) { } 40 provideInitialHead()41 DataType *provideInitialHead() const 42 { return createSentinel(); } 43 ensureHead(DataType *)44 DataType *ensureHead(DataType*) const 45 { return createSentinel(); } 46 noteHead(DataType *,DataType *)47 static void noteHead(DataType*, DataType*) { } 48 49 // override the traits provided in llvm::ilist_node_traits since createNode(const DataType & V)50 static DataType *createNode(const DataType &V) { 51 assert(false && "Only GCFactory knows how to create a node."); 52 } deleteNode(DataType * V)53 static void deleteNode(DataType *V) { 54 // No action. GCFactory will handle it by itself. 55 } 56 57 private: 58 mutable SentinelNode mSentinel; 59 }; 60 61 } // namespace of mcld 62 63 #endif 64