1 //===--- ModuleManager.cpp - Module Manager ---------------------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file defines the ModuleManager class, which manages a set of loaded 11 // modules for the ASTReader. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #ifndef LLVM_CLANG_SERIALIZATION_MODULE_MANAGER_H 16 #define LLVM_CLANG_SERIALIZATION_MODULE_MANAGER_H 17 18 #include "clang/Basic/FileManager.h" 19 #include "clang/Serialization/Module.h" 20 #include "llvm/ADT/DenseMap.h" 21 #include "llvm/ADT/SmallPtrSet.h" 22 23 namespace clang { 24 25 class GlobalModuleIndex; 26 class ModuleMap; 27 28 namespace serialization { 29 30 /// \brief Manages the set of modules loaded by an AST reader. 31 class ModuleManager { 32 /// \brief The chain of AST files. The first entry is the one named by the 33 /// user, the last one is the one that doesn't depend on anything further. 34 SmallVector<ModuleFile *, 2> Chain; 35 36 /// \brief All loaded modules, indexed by name. 37 llvm::DenseMap<const FileEntry *, ModuleFile *> Modules; 38 39 /// \brief FileManager that handles translating between filenames and 40 /// FileEntry *. 41 FileManager &FileMgr; 42 43 /// \brief A lookup of in-memory (virtual file) buffers 44 llvm::DenseMap<const FileEntry *, llvm::MemoryBuffer *> InMemoryBuffers; 45 46 /// \brief The visitation order. 47 SmallVector<ModuleFile *, 4> VisitOrder; 48 49 /// \brief The list of module files that both we and the global module index 50 /// know about. 51 /// 52 /// Either the global index or the module manager may have modules that the 53 /// other does not know about, because the global index can be out-of-date 54 /// (in which case the module manager could have modules it does not) and 55 /// this particular translation unit might not have loaded all of the modules 56 /// known to the global index. 57 SmallVector<ModuleFile *, 4> ModulesInCommonWithGlobalIndex; 58 59 /// \brief The global module index, if one is attached. 60 /// 61 /// The global module index will actually be owned by the ASTReader; this is 62 /// just an non-owning pointer. 63 GlobalModuleIndex *GlobalIndex; 64 65 /// \brief State used by the "visit" operation to avoid malloc traffic in 66 /// calls to visit(). 67 struct VisitState { 68 explicit VisitState(unsigned N) 69 : VisitNumber(N, 0), NextVisitNumber(1), NextState(nullptr) 70 { 71 Stack.reserve(N); 72 } 73 74 ~VisitState() { 75 delete NextState; 76 } 77 78 /// \brief The stack used when marking the imports of a particular module 79 /// as not-to-be-visited. 80 SmallVector<ModuleFile *, 4> Stack; 81 82 /// \brief The visit number of each module file, which indicates when 83 /// this module file was last visited. 84 SmallVector<unsigned, 4> VisitNumber; 85 86 /// \brief The next visit number to use to mark visited module files. 87 unsigned NextVisitNumber; 88 89 /// \brief The next visit state. 90 VisitState *NextState; 91 }; 92 93 /// \brief The first visit() state in the chain. 94 VisitState *FirstVisitState; 95 96 VisitState *allocateVisitState(); 97 void returnVisitState(VisitState *State); 98 99 public: 100 typedef SmallVectorImpl<ModuleFile*>::iterator ModuleIterator; 101 typedef SmallVectorImpl<ModuleFile*>::const_iterator ModuleConstIterator; 102 typedef SmallVectorImpl<ModuleFile*>::reverse_iterator ModuleReverseIterator; 103 typedef std::pair<uint32_t, StringRef> ModuleOffset; 104 105 explicit ModuleManager(FileManager &FileMgr); 106 ~ModuleManager(); 107 108 /// \brief Forward iterator to traverse all loaded modules. This is reverse 109 /// source-order. 110 ModuleIterator begin() { return Chain.begin(); } 111 /// \brief Forward iterator end-point to traverse all loaded modules 112 ModuleIterator end() { return Chain.end(); } 113 114 /// \brief Const forward iterator to traverse all loaded modules. This is 115 /// in reverse source-order. 116 ModuleConstIterator begin() const { return Chain.begin(); } 117 /// \brief Const forward iterator end-point to traverse all loaded modules 118 ModuleConstIterator end() const { return Chain.end(); } 119 120 /// \brief Reverse iterator to traverse all loaded modules. This is in 121 /// source order. 122 ModuleReverseIterator rbegin() { return Chain.rbegin(); } 123 /// \brief Reverse iterator end-point to traverse all loaded modules. 124 ModuleReverseIterator rend() { return Chain.rend(); } 125 126 /// \brief Returns the primary module associated with the manager, that is, 127 /// the first module loaded 128 ModuleFile &getPrimaryModule() { return *Chain[0]; } 129 130 /// \brief Returns the primary module associated with the manager, that is, 131 /// the first module loaded. 132 ModuleFile &getPrimaryModule() const { return *Chain[0]; } 133 134 /// \brief Returns the module associated with the given index 135 ModuleFile &operator[](unsigned Index) const { return *Chain[Index]; } 136 137 /// \brief Returns the module associated with the given name 138 ModuleFile *lookup(StringRef Name); 139 140 /// \brief Returns the module associated with the given module file. 141 ModuleFile *lookup(const FileEntry *File); 142 143 /// \brief Returns the in-memory (virtual file) buffer with the given name 144 llvm::MemoryBuffer *lookupBuffer(StringRef Name); 145 146 /// \brief Number of modules loaded 147 unsigned size() const { return Chain.size(); } 148 149 /// \brief The result of attempting to add a new module. 150 enum AddModuleResult { 151 /// \brief The module file had already been loaded. 152 AlreadyLoaded, 153 /// \brief The module file was just loaded in response to this call. 154 NewlyLoaded, 155 /// \brief The module file is missing. 156 Missing, 157 /// \brief The module file is out-of-date. 158 OutOfDate 159 }; 160 161 /// \brief Attempts to create a new module and add it to the list of known 162 /// modules. 163 /// 164 /// \param FileName The file name of the module to be loaded. 165 /// 166 /// \param Type The kind of module being loaded. 167 /// 168 /// \param ImportLoc The location at which the module is imported. 169 /// 170 /// \param ImportedBy The module that is importing this module, or NULL if 171 /// this module is imported directly by the user. 172 /// 173 /// \param Generation The generation in which this module was loaded. 174 /// 175 /// \param ExpectedSize The expected size of the module file, used for 176 /// validation. This will be zero if unknown. 177 /// 178 /// \param ExpectedModTime The expected modification time of the module 179 /// file, used for validation. This will be zero if unknown. 180 /// 181 /// \param Module A pointer to the module file if the module was successfully 182 /// loaded. 183 /// 184 /// \param ErrorStr Will be set to a non-empty string if any errors occurred 185 /// while trying to load the module. 186 /// 187 /// \return A pointer to the module that corresponds to this file name, 188 /// and a value indicating whether the module was loaded. 189 AddModuleResult addModule(StringRef FileName, ModuleKind Type, 190 SourceLocation ImportLoc, 191 ModuleFile *ImportedBy, unsigned Generation, 192 off_t ExpectedSize, time_t ExpectedModTime, 193 ModuleFile *&Module, 194 std::string &ErrorStr); 195 196 /// \brief Remove the given set of modules. 197 void removeModules(ModuleIterator first, ModuleIterator last, 198 llvm::SmallPtrSetImpl<ModuleFile *> &LoadedSuccessfully, 199 ModuleMap *modMap); 200 201 /// \brief Add an in-memory buffer the list of known buffers 202 void addInMemoryBuffer(StringRef FileName, llvm::MemoryBuffer *Buffer); 203 204 /// \brief Set the global module index. 205 void setGlobalIndex(GlobalModuleIndex *Index); 206 207 /// \brief Notification from the AST reader that the given module file 208 /// has been "accepted", and will not (can not) be unloaded. 209 void moduleFileAccepted(ModuleFile *MF); 210 211 /// \brief Visit each of the modules. 212 /// 213 /// This routine visits each of the modules, starting with the 214 /// "root" modules that no other loaded modules depend on, and 215 /// proceeding to the leaf modules, visiting each module only once 216 /// during the traversal. 217 /// 218 /// This traversal is intended to support various "lookup" 219 /// operations that can find data in any of the loaded modules. 220 /// 221 /// \param Visitor A visitor function that will be invoked with each 222 /// module and the given user data pointer. The return value must be 223 /// convertible to bool; when false, the visitation continues to 224 /// modules that the current module depends on. When true, the 225 /// visitation skips any modules that the current module depends on. 226 /// 227 /// \param UserData User data associated with the visitor object, which 228 /// will be passed along to the visitor. 229 /// 230 /// \param ModuleFilesHit If non-NULL, contains the set of module files 231 /// that we know we need to visit because the global module index told us to. 232 /// Any module that is known to both the global module index and the module 233 /// manager that is *not* in this set can be skipped. 234 void visit(bool (*Visitor)(ModuleFile &M, void *UserData), void *UserData, 235 llvm::SmallPtrSet<ModuleFile *, 4> *ModuleFilesHit = nullptr); 236 237 /// \brief Visit each of the modules with a depth-first traversal. 238 /// 239 /// This routine visits each of the modules known to the module 240 /// manager using a depth-first search, starting with the first 241 /// loaded module. The traversal invokes the callback both before 242 /// traversing the children (preorder traversal) and after 243 /// traversing the children (postorder traversal). 244 /// 245 /// \param Visitor A visitor function that will be invoked with each 246 /// module and given a \c Preorder flag that indicates whether we're 247 /// visiting the module before or after visiting its children. The 248 /// visitor may return true at any time to abort the depth-first 249 /// visitation. 250 /// 251 /// \param UserData User data ssociated with the visitor object, 252 /// which will be passed along to the user. 253 void visitDepthFirst(bool (*Visitor)(ModuleFile &M, bool Preorder, 254 void *UserData), 255 void *UserData); 256 257 /// \brief Attempt to resolve the given module file name to a file entry. 258 /// 259 /// \param FileName The name of the module file. 260 /// 261 /// \param ExpectedSize The size that the module file is expected to have. 262 /// If the actual size differs, the resolver should return \c true. 263 /// 264 /// \param ExpectedModTime The modification time that the module file is 265 /// expected to have. If the actual modification time differs, the resolver 266 /// should return \c true. 267 /// 268 /// \param File Will be set to the file if there is one, or null 269 /// otherwise. 270 /// 271 /// \returns True if a file exists but does not meet the size/ 272 /// modification time criteria, false if the file is either available and 273 /// suitable, or is missing. 274 bool lookupModuleFile(StringRef FileName, 275 off_t ExpectedSize, 276 time_t ExpectedModTime, 277 const FileEntry *&File); 278 279 /// \brief View the graphviz representation of the module graph. 280 void viewGraph(); 281 }; 282 283 } } // end namespace clang::serialization 284 285 #endif 286
