/* * Copyright (C) 2011 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #ifndef ART_RUNTIME_CLASS_LINKER_H_ #define ART_RUNTIME_CLASS_LINKER_H_ #include #include #include #include #include #include #include "base/allocator.h" #include "base/hash_set.h" #include "base/macros.h" #include "base/mutex.h" #include "class_table.h" #include "dex_cache_resolved_classes.h" #include "dex_file.h" #include "gc_root.h" #include "jni.h" #include "oat_file.h" #include "object_callbacks.h" namespace art { namespace gc { namespace space { class ImageSpace; } // namespace space } // namespace gc namespace mirror { class ClassLoader; class DexCache; class DexCachePointerArray; class DexCacheTest_Open_Test; class IfTable; template class ObjectArray; class StackTraceElement; } // namespace mirror class ImtConflictTable; template class Handle; template class MutableHandle; class InternTable; template class ObjectLock; class Runtime; class ScopedObjectAccessAlreadyRunnable; template class PACKED(4) StackHandleScope; enum VisitRootFlags : uint8_t; class ClassVisitor { public: virtual ~ClassVisitor() {} // Return true to continue visiting. virtual bool operator()(mirror::Class* klass) = 0; }; class ClassLoaderVisitor { public: virtual ~ClassLoaderVisitor() {} virtual void Visit(mirror::ClassLoader* class_loader) SHARED_REQUIRES(Locks::classlinker_classes_lock_, Locks::mutator_lock_) = 0; }; class ClassLinker { public: // Well known mirror::Class roots accessed via GetClassRoot. enum ClassRoot { kJavaLangClass, kJavaLangObject, kClassArrayClass, kObjectArrayClass, kJavaLangString, kJavaLangDexCache, kJavaLangRefReference, kJavaLangReflectConstructor, kJavaLangReflectField, kJavaLangReflectMethod, kJavaLangReflectProxy, kJavaLangStringArrayClass, kJavaLangReflectConstructorArrayClass, kJavaLangReflectFieldArrayClass, kJavaLangReflectMethodArrayClass, kJavaLangClassLoader, kJavaLangThrowable, kJavaLangClassNotFoundException, kJavaLangStackTraceElement, kPrimitiveBoolean, kPrimitiveByte, kPrimitiveChar, kPrimitiveDouble, kPrimitiveFloat, kPrimitiveInt, kPrimitiveLong, kPrimitiveShort, kPrimitiveVoid, kBooleanArrayClass, kByteArrayClass, kCharArrayClass, kDoubleArrayClass, kFloatArrayClass, kIntArrayClass, kLongArrayClass, kShortArrayClass, kJavaLangStackTraceElementArrayClass, kClassRootsMax, }; explicit ClassLinker(InternTable* intern_table); ~ClassLinker(); // Initialize class linker by bootstraping from dex files. bool InitWithoutImage(std::vector> boot_class_path, std::string* error_msg) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); // Initialize class linker from one or more boot images. bool InitFromBootImage(std::string* error_msg) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); // Add an image space to the class linker, may fix up classloader fields and dex cache fields. // The dex files that were newly opened for the space are placed in the out argument // out_dex_files. Returns true if the operation succeeded. // The space must be already added to the heap before calling AddImageSpace since we need to // properly handle read barriers and object marking. bool AddImageSpace(gc::space::ImageSpace* space, Handle class_loader, jobjectArray dex_elements, const char* dex_location, std::vector>* out_dex_files, std::string* error_msg) REQUIRES(!dex_lock_) SHARED_REQUIRES(Locks::mutator_lock_); bool OpenImageDexFiles(gc::space::ImageSpace* space, std::vector>* out_dex_files, std::string* error_msg) REQUIRES(!dex_lock_) SHARED_REQUIRES(Locks::mutator_lock_); // Finds a class by its descriptor, loading it if necessary. // If class_loader is null, searches boot_class_path_. mirror::Class* FindClass(Thread* self, const char* descriptor, Handle class_loader) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); // Finds a class in the path class loader, loading it if necessary without using JNI. Hash // function is supposed to be ComputeModifiedUtf8Hash(descriptor). Returns true if the // class-loader chain could be handled, false otherwise, i.e., a non-supported class-loader // was encountered while walking the parent chain (currently only BootClassLoader and // PathClassLoader are supported). bool FindClassInPathClassLoader(ScopedObjectAccessAlreadyRunnable& soa, Thread* self, const char* descriptor, size_t hash, Handle class_loader, mirror::Class** result) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); // Finds a class by its descriptor using the "system" class loader, ie by searching the // boot_class_path_. mirror::Class* FindSystemClass(Thread* self, const char* descriptor) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); // Finds the array class given for the element class. mirror::Class* FindArrayClass(Thread* self, mirror::Class** element_class) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); // Returns true if the class linker is initialized. bool IsInitialized() const { return init_done_; } // Define a new a class based on a ClassDef from a DexFile mirror::Class* DefineClass(Thread* self, const char* descriptor, size_t hash, Handle class_loader, const DexFile& dex_file, const DexFile::ClassDef& dex_class_def) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); // Finds a class by its descriptor, returning null if it isn't wasn't loaded // by the given 'class_loader'. mirror::Class* LookupClass(Thread* self, const char* descriptor, size_t hash, mirror::ClassLoader* class_loader) REQUIRES(!Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); // Finds all the classes with the given descriptor, regardless of ClassLoader. void LookupClasses(const char* descriptor, std::vector& classes) REQUIRES(!Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); mirror::Class* FindPrimitiveClass(char type) SHARED_REQUIRES(Locks::mutator_lock_); // General class unloading is not supported, this is used to prune // unwanted classes during image writing. bool RemoveClass(const char* descriptor, mirror::ClassLoader* class_loader) REQUIRES(!Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); void DumpAllClasses(int flags) REQUIRES(!Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); void DumpForSigQuit(std::ostream& os) REQUIRES(!Locks::classlinker_classes_lock_); size_t NumLoadedClasses() REQUIRES(!Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); // Resolve a String with the given index from the DexFile, storing the // result in the DexCache. The referrer is used to identify the // target DexCache and ClassLoader to use for resolution. mirror::String* ResolveString(uint32_t string_idx, ArtMethod* referrer) SHARED_REQUIRES(Locks::mutator_lock_); // Resolve a String with the given index from the DexFile, storing the // result in the DexCache. mirror::String* ResolveString(const DexFile& dex_file, uint32_t string_idx, Handle dex_cache) SHARED_REQUIRES(Locks::mutator_lock_); // Find a String with the given index from the DexFile, storing the // result in the DexCache if found. Return null if not found. mirror::String* LookupString(const DexFile& dex_file, uint32_t string_idx, Handle dex_cache) SHARED_REQUIRES(Locks::mutator_lock_); // Resolve a Type with the given index from the DexFile, storing the // result in the DexCache. The referrer is used to identity the // target DexCache and ClassLoader to use for resolution. mirror::Class* ResolveType(const DexFile& dex_file, uint16_t type_idx, mirror::Class* referrer) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_, !Roles::uninterruptible_); // Resolve a Type with the given index from the DexFile, storing the // result in the DexCache. The referrer is used to identify the // target DexCache and ClassLoader to use for resolution. mirror::Class* ResolveType(uint16_t type_idx, ArtMethod* referrer) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_, !Roles::uninterruptible_); mirror::Class* ResolveType(uint16_t type_idx, ArtField* referrer) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_, !Roles::uninterruptible_); // Resolve a type with the given ID from the DexFile, storing the // result in DexCache. The ClassLoader is used to search for the // type, since it may be referenced from but not contained within // the given DexFile. mirror::Class* ResolveType(const DexFile& dex_file, uint16_t type_idx, Handle dex_cache, Handle class_loader) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_, !Roles::uninterruptible_); // Determine whether a dex cache result should be trusted, or an IncompatibleClassChangeError // check should be performed even after a hit. enum ResolveMode { // private. kNoICCECheckForCache, kForceICCECheck }; // Resolve a method with a given ID from the DexFile, storing the // result in DexCache. The ClassLinker and ClassLoader are used as // in ResolveType. What is unique is the method type argument which // is used to determine if this method is a direct, static, or // virtual method. template ArtMethod* ResolveMethod(const DexFile& dex_file, uint32_t method_idx, Handle dex_cache, Handle class_loader, ArtMethod* referrer, InvokeType type) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_, !Roles::uninterruptible_); ArtMethod* GetResolvedMethod(uint32_t method_idx, ArtMethod* referrer) SHARED_REQUIRES(Locks::mutator_lock_); // This returns the class referred to by GetMethodId(method_idx).class_idx_. This might be // different then the declaring class of the resolved method due to copied // miranda/default/conflict methods. mirror::Class* ResolveReferencedClassOfMethod(uint32_t method_idx, Handle dex_cache, Handle class_loader) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_, !Roles::uninterruptible_); template ArtMethod* ResolveMethod(Thread* self, uint32_t method_idx, ArtMethod* referrer, InvokeType type) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_, !Roles::uninterruptible_); ArtMethod* ResolveMethodWithoutInvokeType(const DexFile& dex_file, uint32_t method_idx, Handle dex_cache, Handle class_loader) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_, !Roles::uninterruptible_); ArtField* GetResolvedField(uint32_t field_idx, mirror::Class* field_declaring_class) SHARED_REQUIRES(Locks::mutator_lock_); ArtField* GetResolvedField(uint32_t field_idx, mirror::DexCache* dex_cache) SHARED_REQUIRES(Locks::mutator_lock_); ArtField* ResolveField(uint32_t field_idx, ArtMethod* referrer, bool is_static) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_, !Roles::uninterruptible_); // Resolve a field with a given ID from the DexFile, storing the // result in DexCache. The ClassLinker and ClassLoader are used as // in ResolveType. What is unique is the is_static argument which is // used to determine if we are resolving a static or non-static // field. ArtField* ResolveField(const DexFile& dex_file, uint32_t field_idx, Handle dex_cache, Handle class_loader, bool is_static) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_, !Roles::uninterruptible_); // Resolve a field with a given ID from the DexFile, storing the // result in DexCache. The ClassLinker and ClassLoader are used as // in ResolveType. No is_static argument is provided so that Java // field resolution semantics are followed. ArtField* ResolveFieldJLS(const DexFile& dex_file, uint32_t field_idx, Handle dex_cache, Handle class_loader) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_, !Roles::uninterruptible_); // Get shorty from method index without resolution. Used to do handlerization. const char* MethodShorty(uint32_t method_idx, ArtMethod* referrer, uint32_t* length) SHARED_REQUIRES(Locks::mutator_lock_); // Returns true on success, false if there's an exception pending. // can_run_clinit=false allows the compiler to attempt to init a class, // given the restriction that no execution is possible. bool EnsureInitialized(Thread* self, Handle c, bool can_init_fields, bool can_init_parents) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_, !Roles::uninterruptible_); // Initializes classes that have instances in the image but that have // methods so they could not be initialized by the compiler. void RunRootClinits() SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_, !Roles::uninterruptible_); mirror::DexCache* RegisterDexFile(const DexFile& dex_file, mirror::ClassLoader* class_loader) REQUIRES(!dex_lock_) SHARED_REQUIRES(Locks::mutator_lock_); void RegisterDexFile(const DexFile& dex_file, Handle dex_cache) REQUIRES(!dex_lock_) SHARED_REQUIRES(Locks::mutator_lock_); const std::vector& GetBootClassPath() { return boot_class_path_; } void VisitClasses(ClassVisitor* visitor) REQUIRES(!Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); // Less efficient variant of VisitClasses that copies the class_table_ into secondary storage // so that it can visit individual classes without holding the doesn't hold the // Locks::classlinker_classes_lock_. As the Locks::classlinker_classes_lock_ isn't held this code // can race with insertion and deletion of classes while the visitor is being called. void VisitClassesWithoutClassesLock(ClassVisitor* visitor) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); void VisitClassRoots(RootVisitor* visitor, VisitRootFlags flags) REQUIRES(!Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); void VisitRoots(RootVisitor* visitor, VisitRootFlags flags) REQUIRES(!dex_lock_) SHARED_REQUIRES(Locks::mutator_lock_); mirror::DexCache* FindDexCache(Thread* self, const DexFile& dex_file, bool allow_failure = false) REQUIRES(!dex_lock_) SHARED_REQUIRES(Locks::mutator_lock_); void FixupDexCaches(ArtMethod* resolution_method) REQUIRES(!dex_lock_) SHARED_REQUIRES(Locks::mutator_lock_); // Allocate an instance of a java.lang.Object. mirror::Object* AllocObject(Thread* self) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!Roles::uninterruptible_); // TODO: replace this with multiple methods that allocate the correct managed type. template mirror::ObjectArray* AllocObjectArray(Thread* self, size_t length) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!Roles::uninterruptible_); mirror::ObjectArray* AllocClassArray(Thread* self, size_t length) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!Roles::uninterruptible_); mirror::ObjectArray* AllocStringArray(Thread* self, size_t length) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!Roles::uninterruptible_); LengthPrefixedArray* AllocArtFieldArray(Thread* self, LinearAlloc* allocator, size_t length); LengthPrefixedArray* AllocArtMethodArray(Thread* self, LinearAlloc* allocator, size_t length); mirror::PointerArray* AllocPointerArray(Thread* self, size_t length) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!Roles::uninterruptible_); mirror::IfTable* AllocIfTable(Thread* self, size_t ifcount) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!Roles::uninterruptible_); mirror::ObjectArray* AllocStackTraceElementArray(Thread* self, size_t length) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!Roles::uninterruptible_); void VerifyClass(Thread* self, Handle klass, LogSeverity log_level = LogSeverity::NONE) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); bool VerifyClassUsingOatFile(const DexFile& dex_file, mirror::Class* klass, mirror::Class::Status& oat_file_class_status) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); void ResolveClassExceptionHandlerTypes(Handle klass) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); void ResolveMethodExceptionHandlerTypes(ArtMethod* klass) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); mirror::Class* CreateProxyClass(ScopedObjectAccessAlreadyRunnable& soa, jstring name, jobjectArray interfaces, jobject loader, jobjectArray methods, jobjectArray throws) SHARED_REQUIRES(Locks::mutator_lock_); std::string GetDescriptorForProxy(mirror::Class* proxy_class) SHARED_REQUIRES(Locks::mutator_lock_); ArtMethod* FindMethodForProxy(mirror::Class* proxy_class, ArtMethod* proxy_method) REQUIRES(!dex_lock_) SHARED_REQUIRES(Locks::mutator_lock_); // Get the oat code for a method when its class isn't yet initialized const void* GetQuickOatCodeFor(ArtMethod* method) SHARED_REQUIRES(Locks::mutator_lock_); // Get compiled code for a method, return null if no code // exists. This is unlike Get..OatCodeFor which will return a bridge // or interpreter entrypoint. const void* GetOatMethodQuickCodeFor(ArtMethod* method) SHARED_REQUIRES(Locks::mutator_lock_); const OatFile::OatMethod FindOatMethodFor(ArtMethod* method, bool* found) SHARED_REQUIRES(Locks::mutator_lock_); pid_t GetClassesLockOwner(); // For SignalCatcher. pid_t GetDexLockOwner(); // For SignalCatcher. mirror::Class* GetClassRoot(ClassRoot class_root) SHARED_REQUIRES(Locks::mutator_lock_); static const char* GetClassRootDescriptor(ClassRoot class_root); // Is the given entry point quick code to run the resolution stub? bool IsQuickResolutionStub(const void* entry_point) const; // Is the given entry point quick code to bridge into the interpreter? bool IsQuickToInterpreterBridge(const void* entry_point) const; // Is the given entry point quick code to run the generic JNI stub? bool IsQuickGenericJniStub(const void* entry_point) const; InternTable* GetInternTable() const { return intern_table_; } // Set the entrypoints up for method to the given code. void SetEntryPointsToCompiledCode(ArtMethod* method, const void* method_code) const SHARED_REQUIRES(Locks::mutator_lock_); // Set the entrypoints up for method to the enter the interpreter. void SetEntryPointsToInterpreter(ArtMethod* method) const SHARED_REQUIRES(Locks::mutator_lock_); // Attempts to insert a class into a class table. Returns null if // the class was inserted, otherwise returns an existing class with // the same descriptor and ClassLoader. mirror::Class* InsertClass(const char* descriptor, mirror::Class* klass, size_t hash) REQUIRES(!Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); mirror::ObjectArray* GetClassRoots() SHARED_REQUIRES(Locks::mutator_lock_) { mirror::ObjectArray* class_roots = class_roots_.Read(); DCHECK(class_roots != nullptr); return class_roots; } // Move all of the boot image classes into the class table for faster lookups. void AddBootImageClassesToClassTable() REQUIRES(!Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); // Add image classes to the class table. void AddImageClassesToClassTable(std::vector image_spaces, mirror::ClassLoader* class_loader) REQUIRES(!Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); // Move the class table to the pre-zygote table to reduce memory usage. This works by ensuring // that no more classes are ever added to the pre zygote table which makes it that the pages // always remain shared dirty instead of private dirty. void MoveClassTableToPreZygote() REQUIRES(!Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); // Creates a GlobalRef PathClassLoader that can be used to load classes from the given dex files. // Note: the objects are not completely set up. Do not use this outside of tests and the compiler. jobject CreatePathClassLoader(Thread* self, const std::vector& dex_files) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); size_t GetImagePointerSize() const { DCHECK(ValidPointerSize(image_pointer_size_)) << image_pointer_size_; return image_pointer_size_; } // Used by image writer for checking. bool ClassInClassTable(mirror::Class* klass) REQUIRES(Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); ArtMethod* CreateRuntimeMethod(LinearAlloc* linear_alloc); // Clear the ArrayClass cache. This is necessary when cleaning up for the image, as the cache // entries are roots, but potentially not image classes. void DropFindArrayClassCache() SHARED_REQUIRES(Locks::mutator_lock_); // Clean up class loaders, this needs to happen after JNI weak globals are cleared. void CleanupClassLoaders() REQUIRES(!Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); // Unlike GetOrCreateAllocatorForClassLoader, GetAllocatorForClassLoader asserts that the // allocator for this class loader is already created. LinearAlloc* GetAllocatorForClassLoader(mirror::ClassLoader* class_loader) SHARED_REQUIRES(Locks::mutator_lock_); // Return the linear alloc for a class loader if it is already allocated, otherwise allocate and // set it. TODO: Consider using a lock other than classlinker_classes_lock_. LinearAlloc* GetOrCreateAllocatorForClassLoader(mirror::ClassLoader* class_loader) REQUIRES(!Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); // May be called with null class_loader due to legacy code. b/27954959 void InsertDexFileInToClassLoader(mirror::Object* dex_file, mirror::ClassLoader* class_loader) REQUIRES(!Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); static bool ShouldUseInterpreterEntrypoint(ArtMethod* method, const void* quick_code) SHARED_REQUIRES(Locks::mutator_lock_); std::set GetResolvedClasses(bool ignore_boot_classes) REQUIRES(!dex_lock_); std::unordered_set GetClassDescriptorsForProfileKeys( const std::set& classes) REQUIRES(!dex_lock_); static bool IsBootClassLoader(ScopedObjectAccessAlreadyRunnable& soa, mirror::ClassLoader* class_loader) SHARED_REQUIRES(Locks::mutator_lock_); ArtMethod* AddMethodToConflictTable(mirror::Class* klass, ArtMethod* conflict_method, ArtMethod* interface_method, ArtMethod* method, bool force_new_conflict_method) SHARED_REQUIRES(Locks::mutator_lock_); // Create a conflict table with a specified capacity. ImtConflictTable* CreateImtConflictTable(size_t count, LinearAlloc* linear_alloc); // Static version for when the class linker is not yet created. static ImtConflictTable* CreateImtConflictTable(size_t count, LinearAlloc* linear_alloc, size_t pointer_size); // Create the IMT and conflict tables for a class. void FillIMTAndConflictTables(mirror::Class* klass) SHARED_REQUIRES(Locks::mutator_lock_); // Clear class table strong roots (other than classes themselves). This is done by dex2oat to // allow pruning dex caches. void ClearClassTableStrongRoots() const REQUIRES(!Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); // Throw the class initialization failure recorded when first trying to initialize the given // class. void ThrowEarlierClassFailure(mirror::Class* c, bool wrap_in_no_class_def = false) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); struct DexCacheData { // Weak root to the DexCache. Note: Do not decode this unnecessarily or else class unloading may // not work properly. jweak weak_root; // The following two fields are caches to the DexCache's fields and here to avoid unnecessary // jweak decode that triggers read barriers (and mark them alive unnecessarily and mess with // class unloading.) const DexFile* dex_file; GcRoot* resolved_types; }; private: struct ClassLoaderData { jweak weak_root; // Weak root to enable class unloading. ClassTable* class_table; LinearAlloc* allocator; }; // Ensures that the supertype of 'klass' ('supertype') is verified. Returns false and throws // appropriate exceptions if verification failed hard. Returns true for successful verification or // soft-failures. bool AttemptSupertypeVerification(Thread* self, Handle klass, Handle supertype) REQUIRES(!dex_lock_) SHARED_REQUIRES(Locks::mutator_lock_); static void DeleteClassLoader(Thread* self, const ClassLoaderData& data) REQUIRES(Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); void VisitClassLoaders(ClassLoaderVisitor* visitor) const SHARED_REQUIRES(Locks::classlinker_classes_lock_, Locks::mutator_lock_); void VisitClassesInternal(ClassVisitor* visitor) SHARED_REQUIRES(Locks::classlinker_classes_lock_, Locks::mutator_lock_); // Returns the number of zygote and image classes. size_t NumZygoteClasses() const REQUIRES(Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); // Returns the number of non zygote nor image classes. size_t NumNonZygoteClasses() const REQUIRES(Locks::classlinker_classes_lock_) SHARED_REQUIRES(Locks::mutator_lock_); void FinishInit(Thread* self) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_, !Roles::uninterruptible_); // For early bootstrapping by Init mirror::Class* AllocClass(Thread* self, mirror::Class* java_lang_Class, uint32_t class_size) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!Roles::uninterruptible_); // Alloc* convenience functions to avoid needing to pass in mirror::Class* // values that are known to the ClassLinker such as // kObjectArrayClass and kJavaLangString etc. mirror::Class* AllocClass(Thread* self, uint32_t class_size) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!Roles::uninterruptible_); mirror::DexCache* AllocDexCache(Thread* self, const DexFile& dex_file, LinearAlloc* linear_alloc) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!Roles::uninterruptible_); mirror::Class* CreatePrimitiveClass(Thread* self, Primitive::Type type) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!Roles::uninterruptible_); mirror::Class* InitializePrimitiveClass(mirror::Class* primitive_class, Primitive::Type type) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!Roles::uninterruptible_); mirror::Class* CreateArrayClass(Thread* self, const char* descriptor, size_t hash, Handle class_loader) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_, !Roles::uninterruptible_); void AppendToBootClassPath(Thread* self, const DexFile& dex_file) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); void AppendToBootClassPath(const DexFile& dex_file, Handle dex_cache) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); // Precomputes size needed for Class, in the case of a non-temporary class this size must be // sufficient to hold all static fields. uint32_t SizeOfClassWithoutEmbeddedTables(const DexFile& dex_file, const DexFile::ClassDef& dex_class_def); // Setup the classloader, class def index, type idx so that we can insert this class in the class // table. void SetupClass(const DexFile& dex_file, const DexFile::ClassDef& dex_class_def, Handle klass, mirror::ClassLoader* class_loader) SHARED_REQUIRES(Locks::mutator_lock_); void LoadClass(Thread* self, const DexFile& dex_file, const DexFile::ClassDef& dex_class_def, Handle klass) SHARED_REQUIRES(Locks::mutator_lock_); void LoadClassMembers(Thread* self, const DexFile& dex_file, const uint8_t* class_data, Handle klass, const OatFile::OatClass* oat_class) SHARED_REQUIRES(Locks::mutator_lock_); void LoadField(const ClassDataItemIterator& it, Handle klass, ArtField* dst) SHARED_REQUIRES(Locks::mutator_lock_); void LoadMethod(Thread* self, const DexFile& dex_file, const ClassDataItemIterator& it, Handle klass, ArtMethod* dst) SHARED_REQUIRES(Locks::mutator_lock_); void FixupStaticTrampolines(mirror::Class* klass) SHARED_REQUIRES(Locks::mutator_lock_); // Finds the associated oat class for a dex_file and descriptor. Returns an invalid OatClass on // error and sets found to false. OatFile::OatClass FindOatClass(const DexFile& dex_file, uint16_t class_def_idx, bool* found) SHARED_REQUIRES(Locks::mutator_lock_); void RegisterDexFileLocked(const DexFile& dex_file, Handle dex_cache) REQUIRES(dex_lock_) SHARED_REQUIRES(Locks::mutator_lock_); mirror::DexCache* FindDexCacheLocked(Thread* self, const DexFile& dex_file, bool allow_failure) REQUIRES(dex_lock_) SHARED_REQUIRES(Locks::mutator_lock_); bool InitializeClass(Thread* self, Handle klass, bool can_run_clinit, bool can_init_parents) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); bool InitializeDefaultInterfaceRecursive(Thread* self, Handle klass, bool can_run_clinit, bool can_init_parents) REQUIRES(!dex_lock_) SHARED_REQUIRES(Locks::mutator_lock_); bool WaitForInitializeClass(Handle klass, Thread* self, ObjectLock& lock); bool ValidateSuperClassDescriptors(Handle klass) SHARED_REQUIRES(Locks::mutator_lock_); bool IsSameDescriptorInDifferentClassContexts(Thread* self, const char* descriptor, Handle class_loader1, Handle class_loader2) SHARED_REQUIRES(Locks::mutator_lock_); bool IsSameMethodSignatureInDifferentClassContexts(Thread* self, ArtMethod* method, mirror::Class* klass1, mirror::Class* klass2) SHARED_REQUIRES(Locks::mutator_lock_); bool LinkClass(Thread* self, const char* descriptor, Handle klass, Handle> interfaces, MutableHandle* h_new_class_out) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!Locks::classlinker_classes_lock_); bool LinkSuperClass(Handle klass) SHARED_REQUIRES(Locks::mutator_lock_); bool LoadSuperAndInterfaces(Handle klass, const DexFile& dex_file) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); bool LinkMethods(Thread* self, Handle klass, Handle> interfaces, ArtMethod** out_imt) SHARED_REQUIRES(Locks::mutator_lock_); // Does anything needed to make sure that the compiler will not generate a direct invoke to this // method. Should only be called on non-invokable methods. void EnsureThrowsInvocationError(ArtMethod* method) SHARED_REQUIRES(Locks::mutator_lock_); // A wrapper class representing the result of a method translation used for linking methods and // updating superclass default methods. For each method in a classes vtable there are 4 states it // could be in: // 1) No translation is necessary. In this case there is no MethodTranslation object for it. This // is the standard case and is true when the method is not overridable by a default method, // the class defines a concrete implementation of the method, the default method implementation // remains the same, or an abstract method stayed abstract. // 2) The method must be translated to a different default method. We note this with // CreateTranslatedMethod. // 3) The method must be replaced with a conflict method. This happens when a superclass // implements an interface with a default method and this class implements an unrelated // interface that also defines that default method. We note this with CreateConflictingMethod. // 4) The method must be replaced with an abstract miranda method. This happens when a superclass // implements an interface with a default method and this class implements a subinterface of // the superclass's interface which declares the default method abstract. We note this with // CreateAbstractMethod. // // When a method translation is unnecessary (case #1), we don't put it into the // default_translation maps. So an instance of MethodTranslation must be in one of #2-#4. class MethodTranslation { public: // This slot must become a default conflict method. static MethodTranslation CreateConflictingMethod() { return MethodTranslation(Type::kConflict, /*translation*/nullptr); } // This slot must become an abstract method. static MethodTranslation CreateAbstractMethod() { return MethodTranslation(Type::kAbstract, /*translation*/nullptr); } // Use the given method as the current value for this vtable slot during translation. static MethodTranslation CreateTranslatedMethod(ArtMethod* new_method) { return MethodTranslation(Type::kTranslation, new_method); } // Returns true if this is a method that must become a conflict method. bool IsInConflict() const { return type_ == Type::kConflict; } // Returns true if this is a method that must become an abstract method. bool IsAbstract() const { return type_ == Type::kAbstract; } // Returns true if this is a method that must become a different method. bool IsTranslation() const { return type_ == Type::kTranslation; } // Get the translated version of this method. ArtMethod* GetTranslation() const { DCHECK(IsTranslation()); DCHECK(translation_ != nullptr); return translation_; } private: enum class Type { kTranslation, kConflict, kAbstract, }; MethodTranslation(Type type, ArtMethod* translation) : translation_(translation), type_(type) {} ArtMethod* const translation_; const Type type_; }; // Links the virtual methods for the given class and records any default methods that will need to // be updated later. // // Arguments: // * self - The current thread. // * klass - class, whose vtable will be filled in. // * default_translations - Vtable index to new method map. // Any vtable entries that need to be updated with new default methods // are stored into the default_translations map. The default_translations // map is keyed on the vtable index that needs to be updated. We use this // map because if we override a default method with another default // method we need to update the vtable to point to the new method. // Unfortunately since we copy the ArtMethod* we cannot just do a simple // scan, we therefore store the vtable index's that might need to be // updated with the method they will turn into. // TODO This whole default_translations thing is very dirty. There should be a better way. bool LinkVirtualMethods( Thread* self, Handle klass, /*out*/std::unordered_map* default_translations) SHARED_REQUIRES(Locks::mutator_lock_); // Sets up the interface lookup table (IFTable) in the correct order to allow searching for // default methods. bool SetupInterfaceLookupTable(Thread* self, Handle klass, Handle> interfaces) SHARED_REQUIRES(Locks::mutator_lock_); enum class DefaultMethodSearchResult { kDefaultFound, kAbstractFound, kDefaultConflict }; // Find the default method implementation for 'interface_method' in 'klass', if one exists. // // Arguments: // * self - The current thread. // * target_method - The method we are trying to find a default implementation for. // * klass - The class we are searching for a definition of target_method. // * out_default_method - The pointer we will store the found default method to on success. // // Return value: // * kDefaultFound - There were no conflicting method implementations found in the class while // searching for target_method. The default method implementation is stored into // out_default_method. // * kAbstractFound - There were no conflicting method implementations found in the class while // searching for target_method but no default implementation was found either. // out_default_method is set to null and the method should be considered not // implemented. // * kDefaultConflict - Conflicting method implementations were found when searching for // target_method. The value of *out_default_method is null. DefaultMethodSearchResult FindDefaultMethodImplementation( Thread* self, ArtMethod* target_method, Handle klass, /*out*/ArtMethod** out_default_method) const SHARED_REQUIRES(Locks::mutator_lock_); // Sets the imt entries and fixes up the vtable for the given class by linking all the interface // methods. See LinkVirtualMethods for an explanation of what default_translations is. bool LinkInterfaceMethods( Thread* self, Handle klass, const std::unordered_map& default_translations, ArtMethod** out_imt) SHARED_REQUIRES(Locks::mutator_lock_); bool LinkStaticFields(Thread* self, Handle klass, size_t* class_size) SHARED_REQUIRES(Locks::mutator_lock_); bool LinkInstanceFields(Thread* self, Handle klass) SHARED_REQUIRES(Locks::mutator_lock_); bool LinkFields(Thread* self, Handle klass, bool is_static, size_t* class_size) SHARED_REQUIRES(Locks::mutator_lock_); void LinkCode(ArtMethod* method, const OatFile::OatClass* oat_class, uint32_t class_def_method_index) SHARED_REQUIRES(Locks::mutator_lock_); void CreateReferenceInstanceOffsets(Handle klass) SHARED_REQUIRES(Locks::mutator_lock_); void CheckProxyConstructor(ArtMethod* constructor) const SHARED_REQUIRES(Locks::mutator_lock_); void CheckProxyMethod(ArtMethod* method, ArtMethod* prototype) const SHARED_REQUIRES(Locks::mutator_lock_); // For use by ImageWriter to find DexCaches for its roots ReaderWriterMutex* DexLock() SHARED_REQUIRES(Locks::mutator_lock_) LOCK_RETURNED(dex_lock_) { return &dex_lock_; } size_t GetDexCacheCount() SHARED_REQUIRES(Locks::mutator_lock_, dex_lock_) { return dex_caches_.size(); } const std::list& GetDexCachesData() SHARED_REQUIRES(Locks::mutator_lock_, dex_lock_) { return dex_caches_; } void CreateProxyConstructor(Handle klass, ArtMethod* out) SHARED_REQUIRES(Locks::mutator_lock_); void CreateProxyMethod(Handle klass, ArtMethod* prototype, ArtMethod* out) SHARED_REQUIRES(Locks::mutator_lock_); // Ensures that methods have the kAccSkipAccessChecks bit set. We use the // kAccVerificationAttempted bit on the class access flags to determine whether this has been done // before. void EnsureSkipAccessChecksMethods(Handle c) SHARED_REQUIRES(Locks::mutator_lock_); mirror::Class* LookupClassFromBootImage(const char* descriptor) SHARED_REQUIRES(Locks::mutator_lock_); // Register a class loader and create its class table and allocator. Should not be called if // these are already created. void RegisterClassLoader(mirror::ClassLoader* class_loader) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(Locks::classlinker_classes_lock_); // Returns null if not found. ClassTable* ClassTableForClassLoader(mirror::ClassLoader* class_loader) SHARED_REQUIRES(Locks::mutator_lock_); // Insert a new class table if not found. ClassTable* InsertClassTableForClassLoader(mirror::ClassLoader* class_loader) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(Locks::classlinker_classes_lock_); // EnsureResolved is called to make sure that a class in the class_table_ has been resolved // before returning it to the caller. Its the responsibility of the thread that placed the class // in the table to make it resolved. The thread doing resolution must notify on the class' lock // when resolution has occurred. This happens in mirror::Class::SetStatus. As resolution may // retire a class, the version of the class in the table is returned and this may differ from // the class passed in. mirror::Class* EnsureResolved(Thread* self, const char* descriptor, mirror::Class* klass) WARN_UNUSED SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!dex_lock_); void FixupTemporaryDeclaringClass(mirror::Class* temp_class, mirror::Class* new_class) SHARED_REQUIRES(Locks::mutator_lock_); void SetClassRoot(ClassRoot class_root, mirror::Class* klass) SHARED_REQUIRES(Locks::mutator_lock_); // Return the quick generic JNI stub for testing. const void* GetRuntimeQuickGenericJniStub() const; bool CanWeInitializeClass(mirror::Class* klass, bool can_init_statics, bool can_init_parents) SHARED_REQUIRES(Locks::mutator_lock_); void UpdateClassMethods(mirror::Class* klass, LengthPrefixedArray* new_methods) SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(!Locks::classlinker_classes_lock_); // new_class_set is the set of classes that were read from the class table section in the image. // If there was no class table section, it is null. bool UpdateAppImageClassLoadersAndDexCaches( gc::space::ImageSpace* space, Handle class_loader, Handle> dex_caches, ClassTable::ClassSet* new_class_set, bool* out_forward_dex_cache_array, std::string* out_error_msg) REQUIRES(!dex_lock_) SHARED_REQUIRES(Locks::mutator_lock_); // Check that c1 == FindSystemClass(self, descriptor). Abort with class dumps otherwise. void CheckSystemClass(Thread* self, Handle c1, const char* descriptor) REQUIRES(!dex_lock_) SHARED_REQUIRES(Locks::mutator_lock_); // Sets imt_ref appropriately for LinkInterfaceMethods. // If there is no method in the imt location of imt_ref it will store the given method there. // Otherwise it will set the conflict method which will figure out which method to use during // runtime. void SetIMTRef(ArtMethod* unimplemented_method, ArtMethod* imt_conflict_method, ArtMethod* current_method, /*out*/ArtMethod** imt_ref) SHARED_REQUIRES(Locks::mutator_lock_); void FillIMTFromIfTable(mirror::IfTable* if_table, ArtMethod* unimplemented_method, ArtMethod* imt_conflict_method, mirror::Class* klass, bool create_conflict_tables, bool ignore_copied_methods, ArtMethod** imt) SHARED_REQUIRES(Locks::mutator_lock_); void FillImtFromSuperClass(Handle klass, ArtMethod* unimplemented_method, ArtMethod* imt_conflict_method, ArtMethod** imt) SHARED_REQUIRES(Locks::mutator_lock_); std::vector boot_class_path_; std::vector> boot_dex_files_; mutable ReaderWriterMutex dex_lock_ DEFAULT_MUTEX_ACQUIRED_AFTER; // JNI weak globals and side data to allow dex caches to get unloaded. We lazily delete weak // globals when we register new dex files. std::list dex_caches_ GUARDED_BY(dex_lock_); // This contains the class loaders which have class tables. It is populated by // InsertClassTableForClassLoader. std::list class_loaders_ GUARDED_BY(Locks::classlinker_classes_lock_); // Boot class path table. Since the class loader for this is null. ClassTable boot_class_table_ GUARDED_BY(Locks::classlinker_classes_lock_); // New class roots, only used by CMS since the GC needs to mark these in the pause. std::vector> new_class_roots_ GUARDED_BY(Locks::classlinker_classes_lock_); // Do we need to search dex caches to find boot image classes? bool dex_cache_boot_image_class_lookup_required_; // Number of times we've searched dex caches for a class. After a certain number of misses we move // the classes into the class_table_ to avoid dex cache based searches. Atomic failed_dex_cache_class_lookups_; // Well known mirror::Class roots. GcRoot> class_roots_; // The interface table used by all arrays. GcRoot array_iftable_; // A cache of the last FindArrayClass results. The cache serves to avoid creating array class // descriptors for the sake of performing FindClass. static constexpr size_t kFindArrayCacheSize = 16; GcRoot find_array_class_cache_[kFindArrayCacheSize]; size_t find_array_class_cache_next_victim_; bool init_done_; bool log_new_class_table_roots_ GUARDED_BY(Locks::classlinker_classes_lock_); InternTable* intern_table_; // Trampolines within the image the bounce to runtime entrypoints. Done so that there is a single // patch point within the image. TODO: make these proper relocations. const void* quick_resolution_trampoline_; const void* quick_imt_conflict_trampoline_; const void* quick_generic_jni_trampoline_; const void* quick_to_interpreter_bridge_trampoline_; // Image pointer size. size_t image_pointer_size_; friend class ImageDumper; // for DexLock friend class ImageWriter; // for GetClassRoots friend class JniCompilerTest; // for GetRuntimeQuickGenericJniStub friend class JniInternalTest; // for GetRuntimeQuickGenericJniStub ART_FRIEND_TEST(ClassLinkerTest, RegisterDexFileName); // for DexLock, and RegisterDexFileLocked ART_FRIEND_TEST(mirror::DexCacheTest, Open); // for AllocDexCache DISALLOW_COPY_AND_ASSIGN(ClassLinker); }; } // namespace art #endif // ART_RUNTIME_CLASS_LINKER_H_