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_MODULEMANAGER_H 16 #define LLVM_CLANG_SERIALIZATION_MODULEMANAGER_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 typedef llvm::SetVector<const FileEntry *> AdditionalKnownModuleFileSet; 40 41 /// \brief Additional module files that are known but not loaded. Tracked 42 /// here so that we can re-export them if necessary. 43 AdditionalKnownModuleFileSet AdditionalKnownModuleFiles; 44 45 /// \brief FileManager that handles translating between filenames and 46 /// FileEntry *. 47 FileManager &FileMgr; 48 49 /// \brief A lookup of in-memory (virtual file) buffers 50 llvm::DenseMap<const FileEntry *, std::unique_ptr<llvm::MemoryBuffer>> 51 InMemoryBuffers; 52 53 /// \brief The visitation order. 54 SmallVector<ModuleFile *, 4> VisitOrder; 55 56 /// \brief The list of module files that both we and the global module index 57 /// know about. 58 /// 59 /// Either the global index or the module manager may have modules that the 60 /// other does not know about, because the global index can be out-of-date 61 /// (in which case the module manager could have modules it does not) and 62 /// this particular translation unit might not have loaded all of the modules 63 /// known to the global index. 64 SmallVector<ModuleFile *, 4> ModulesInCommonWithGlobalIndex; 65 66 /// \brief The global module index, if one is attached. 67 /// 68 /// The global module index will actually be owned by the ASTReader; this is 69 /// just an non-owning pointer. 70 GlobalModuleIndex *GlobalIndex; 71 72 /// \brief State used by the "visit" operation to avoid malloc traffic in 73 /// calls to visit(). 74 struct VisitState { 75 explicit VisitState(unsigned N) 76 : VisitNumber(N, 0), NextVisitNumber(1), NextState(nullptr) 77 { 78 Stack.reserve(N); 79 } 80 81 ~VisitState() { 82 delete NextState; 83 } 84 85 /// \brief The stack used when marking the imports of a particular module 86 /// as not-to-be-visited. 87 SmallVector<ModuleFile *, 4> Stack; 88 89 /// \brief The visit number of each module file, which indicates when 90 /// this module file was last visited. 91 SmallVector<unsigned, 4> VisitNumber; 92 93 /// \brief The next visit number to use to mark visited module files. 94 unsigned NextVisitNumber; 95 96 /// \brief The next visit state. 97 VisitState *NextState; 98 }; 99 100 /// \brief The first visit() state in the chain. 101 VisitState *FirstVisitState; 102 103 VisitState *allocateVisitState(); 104 void returnVisitState(VisitState *State); 105 106 public: 107 typedef SmallVectorImpl<ModuleFile*>::iterator ModuleIterator; 108 typedef SmallVectorImpl<ModuleFile*>::const_iterator ModuleConstIterator; 109 typedef SmallVectorImpl<ModuleFile*>::reverse_iterator ModuleReverseIterator; 110 typedef std::pair<uint32_t, StringRef> ModuleOffset; 111 112 explicit ModuleManager(FileManager &FileMgr); 113 ~ModuleManager(); 114 115 /// \brief Forward iterator to traverse all loaded modules. This is reverse 116 /// source-order. 117 ModuleIterator begin() { return Chain.begin(); } 118 /// \brief Forward iterator end-point to traverse all loaded modules 119 ModuleIterator end() { return Chain.end(); } 120 121 /// \brief Const forward iterator to traverse all loaded modules. This is 122 /// in reverse source-order. 123 ModuleConstIterator begin() const { return Chain.begin(); } 124 /// \brief Const forward iterator end-point to traverse all loaded modules 125 ModuleConstIterator end() const { return Chain.end(); } 126 127 /// \brief Reverse iterator to traverse all loaded modules. This is in 128 /// source order. 129 ModuleReverseIterator rbegin() { return Chain.rbegin(); } 130 /// \brief Reverse iterator end-point to traverse all loaded modules. 131 ModuleReverseIterator rend() { return Chain.rend(); } 132 133 /// \brief Returns the primary module associated with the manager, that is, 134 /// the first module loaded 135 ModuleFile &getPrimaryModule() { return *Chain[0]; } 136 137 /// \brief Returns the primary module associated with the manager, that is, 138 /// the first module loaded. 139 ModuleFile &getPrimaryModule() const { return *Chain[0]; } 140 141 /// \brief Returns the module associated with the given index 142 ModuleFile &operator[](unsigned Index) const { return *Chain[Index]; } 143 144 /// \brief Returns the module associated with the given name 145 ModuleFile *lookup(StringRef Name); 146 147 /// \brief Returns the module associated with the given module file. 148 ModuleFile *lookup(const FileEntry *File); 149 150 /// \brief Returns the in-memory (virtual file) buffer with the given name 151 std::unique_ptr<llvm::MemoryBuffer> lookupBuffer(StringRef Name); 152 153 /// \brief Number of modules loaded 154 unsigned size() const { return Chain.size(); } 155 156 /// \brief The result of attempting to add a new module. 157 enum AddModuleResult { 158 /// \brief The module file had already been loaded. 159 AlreadyLoaded, 160 /// \brief The module file was just loaded in response to this call. 161 NewlyLoaded, 162 /// \brief The module file is missing. 163 Missing, 164 /// \brief The module file is out-of-date. 165 OutOfDate 166 }; 167 168 typedef ASTFileSignature(*ASTFileSignatureReader)(llvm::BitstreamReader &); 169 170 /// \brief Attempts to create a new module and add it to the list of known 171 /// modules. 172 /// 173 /// \param FileName The file name of the module to be loaded. 174 /// 175 /// \param Type The kind of module being loaded. 176 /// 177 /// \param ImportLoc The location at which the module is imported. 178 /// 179 /// \param ImportedBy The module that is importing this module, or NULL if 180 /// this module is imported directly by the user. 181 /// 182 /// \param Generation The generation in which this module was loaded. 183 /// 184 /// \param ExpectedSize The expected size of the module file, used for 185 /// validation. This will be zero if unknown. 186 /// 187 /// \param ExpectedModTime The expected modification time of the module 188 /// file, used for validation. This will be zero if unknown. 189 /// 190 /// \param ExpectedSignature The expected signature of the module file, used 191 /// for validation. This will be zero if unknown. 192 /// 193 /// \param ReadSignature Reads the signature from an AST file without actually 194 /// loading it. 195 /// 196 /// \param Module A pointer to the module file if the module was successfully 197 /// loaded. 198 /// 199 /// \param ErrorStr Will be set to a non-empty string if any errors occurred 200 /// while trying to load the module. 201 /// 202 /// \return A pointer to the module that corresponds to this file name, 203 /// and a value indicating whether the module was loaded. 204 AddModuleResult addModule(StringRef FileName, ModuleKind Type, 205 SourceLocation ImportLoc, 206 ModuleFile *ImportedBy, unsigned Generation, 207 off_t ExpectedSize, time_t ExpectedModTime, 208 ASTFileSignature ExpectedSignature, 209 ASTFileSignatureReader ReadSignature, 210 ModuleFile *&Module, 211 std::string &ErrorStr); 212 213 /// \brief Remove the given set of modules. 214 void removeModules(ModuleIterator first, ModuleIterator last, 215 llvm::SmallPtrSetImpl<ModuleFile *> &LoadedSuccessfully, 216 ModuleMap *modMap); 217 218 /// \brief Add an in-memory buffer the list of known buffers 219 void addInMemoryBuffer(StringRef FileName, 220 std::unique_ptr<llvm::MemoryBuffer> Buffer); 221 222 /// \brief Set the global module index. 223 void setGlobalIndex(GlobalModuleIndex *Index); 224 225 /// \brief Notification from the AST reader that the given module file 226 /// has been "accepted", and will not (can not) be unloaded. 227 void moduleFileAccepted(ModuleFile *MF); 228 229 /// \brief Notification from the frontend that the given module file is 230 /// part of this compilation (even if not imported) and, if this compilation 231 /// is exported, should be made available to importers of it. 232 bool addKnownModuleFile(StringRef FileName); 233 234 /// \brief Get a list of additional module files that are not currently 235 /// loaded but are considered to be part of the current compilation. 236 llvm::iterator_range<AdditionalKnownModuleFileSet::const_iterator> 237 getAdditionalKnownModuleFiles() { 238 return llvm::make_range(AdditionalKnownModuleFiles.begin(), 239 AdditionalKnownModuleFiles.end()); 240 } 241 242 /// \brief Visit each of the modules. 243 /// 244 /// This routine visits each of the modules, starting with the 245 /// "root" modules that no other loaded modules depend on, and 246 /// proceeding to the leaf modules, visiting each module only once 247 /// during the traversal. 248 /// 249 /// This traversal is intended to support various "lookup" 250 /// operations that can find data in any of the loaded modules. 251 /// 252 /// \param Visitor A visitor function that will be invoked with each 253 /// module and the given user data pointer. The return value must be 254 /// convertible to bool; when false, the visitation continues to 255 /// modules that the current module depends on. When true, the 256 /// visitation skips any modules that the current module depends on. 257 /// 258 /// \param UserData User data associated with the visitor object, which 259 /// will be passed along to the visitor. 260 /// 261 /// \param ModuleFilesHit If non-NULL, contains the set of module files 262 /// that we know we need to visit because the global module index told us to. 263 /// Any module that is known to both the global module index and the module 264 /// manager that is *not* in this set can be skipped. 265 void visit(bool (*Visitor)(ModuleFile &M, void *UserData), void *UserData, 266 llvm::SmallPtrSetImpl<ModuleFile *> *ModuleFilesHit = nullptr); 267 268 /// \brief Visit each of the modules with a depth-first traversal. 269 /// 270 /// This routine visits each of the modules known to the module 271 /// manager using a depth-first search, starting with the first 272 /// loaded module. The traversal invokes the callback both before 273 /// traversing the children (preorder traversal) and after 274 /// traversing the children (postorder traversal). 275 /// 276 /// \param Visitor A visitor function that will be invoked with each 277 /// module and given a \c Preorder flag that indicates whether we're 278 /// visiting the module before or after visiting its children. The 279 /// visitor may return true at any time to abort the depth-first 280 /// visitation. 281 /// 282 /// \param UserData User data ssociated with the visitor object, 283 /// which will be passed along to the user. 284 void visitDepthFirst(bool (*Visitor)(ModuleFile &M, bool Preorder, 285 void *UserData), 286 void *UserData); 287 288 /// \brief Attempt to resolve the given module file name to a file entry. 289 /// 290 /// \param FileName The name of the module file. 291 /// 292 /// \param ExpectedSize The size that the module file is expected to have. 293 /// If the actual size differs, the resolver should return \c true. 294 /// 295 /// \param ExpectedModTime The modification time that the module file is 296 /// expected to have. If the actual modification time differs, the resolver 297 /// should return \c true. 298 /// 299 /// \param File Will be set to the file if there is one, or null 300 /// otherwise. 301 /// 302 /// \returns True if a file exists but does not meet the size/ 303 /// modification time criteria, false if the file is either available and 304 /// suitable, or is missing. 305 bool lookupModuleFile(StringRef FileName, 306 off_t ExpectedSize, 307 time_t ExpectedModTime, 308 const FileEntry *&File); 309 310 /// \brief View the graphviz representation of the module graph. 311 void viewGraph(); 312 }; 313 314 } } // end namespace clang::serialization 315 316 #endif 317
