class_linker.cc revision e48856666e2e959687660f3b708e0c6da210ecb2
1/* 2 * Copyright (C) 2011 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#include "class_linker.h" 18 19#include <deque> 20#include <iostream> 21#include <memory> 22#include <queue> 23#include <string> 24#include <unistd.h> 25#include <utility> 26#include <vector> 27 28#include "base/casts.h" 29#include "base/logging.h" 30#include "base/scoped_flock.h" 31#include "base/stl_util.h" 32#include "base/unix_file/fd_file.h" 33#include "class_linker-inl.h" 34#include "compiler_callbacks.h" 35#include "debugger.h" 36#include "dex_file-inl.h" 37#include "entrypoints/runtime_asm_entrypoints.h" 38#include "gc_root-inl.h" 39#include "gc/accounting/card_table-inl.h" 40#include "gc/accounting/heap_bitmap.h" 41#include "gc/heap.h" 42#include "gc/space/image_space.h" 43#include "handle_scope.h" 44#include "intern_table.h" 45#include "interpreter/interpreter.h" 46#include "jit/jit.h" 47#include "jit/jit_code_cache.h" 48#include "leb128.h" 49#include "oat.h" 50#include "oat_file.h" 51#include "oat_file_assistant.h" 52#include "object_lock.h" 53#include "mirror/art_field-inl.h" 54#include "mirror/art_method-inl.h" 55#include "mirror/class.h" 56#include "mirror/class-inl.h" 57#include "mirror/class_loader.h" 58#include "mirror/dex_cache-inl.h" 59#include "mirror/iftable-inl.h" 60#include "mirror/object-inl.h" 61#include "mirror/object_array-inl.h" 62#include "mirror/proxy.h" 63#include "mirror/reference-inl.h" 64#include "mirror/stack_trace_element.h" 65#include "mirror/string-inl.h" 66#include "os.h" 67#include "runtime.h" 68#include "entrypoints/entrypoint_utils.h" 69#include "ScopedLocalRef.h" 70#include "scoped_thread_state_change.h" 71#include "handle_scope-inl.h" 72#include "thread-inl.h" 73#include "utils.h" 74#include "verifier/method_verifier.h" 75#include "well_known_classes.h" 76 77namespace art { 78 79static void ThrowNoClassDefFoundError(const char* fmt, ...) 80 __attribute__((__format__(__printf__, 1, 2))) 81 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 82static void ThrowNoClassDefFoundError(const char* fmt, ...) { 83 va_list args; 84 va_start(args, fmt); 85 Thread* self = Thread::Current(); 86 self->ThrowNewExceptionV("Ljava/lang/NoClassDefFoundError;", fmt, args); 87 va_end(args); 88} 89 90static void ThrowEarlierClassFailure(mirror::Class* c) 91 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 92 // The class failed to initialize on a previous attempt, so we want to throw 93 // a NoClassDefFoundError (v2 2.17.5). The exception to this rule is if we 94 // failed in verification, in which case v2 5.4.1 says we need to re-throw 95 // the previous error. 96 Runtime* const runtime = Runtime::Current(); 97 if (!runtime->IsAotCompiler()) { // Give info if this occurs at runtime. 98 LOG(INFO) << "Rejecting re-init on previously-failed class " << PrettyClass(c); 99 } 100 101 CHECK(c->IsErroneous()) << PrettyClass(c) << " " << c->GetStatus(); 102 Thread* self = Thread::Current(); 103 if (runtime->IsAotCompiler()) { 104 // At compile time, accurate errors and NCDFE are disabled to speed compilation. 105 mirror::Throwable* pre_allocated = runtime->GetPreAllocatedNoClassDefFoundError(); 106 self->SetException(pre_allocated); 107 } else { 108 if (c->GetVerifyErrorClass() != NULL) { 109 // TODO: change the verifier to store an _instance_, with a useful detail message? 110 std::string temp; 111 self->ThrowNewException(c->GetVerifyErrorClass()->GetDescriptor(&temp), 112 PrettyDescriptor(c).c_str()); 113 } else { 114 self->ThrowNewException("Ljava/lang/NoClassDefFoundError;", 115 PrettyDescriptor(c).c_str()); 116 } 117 } 118} 119 120static void VlogClassInitializationFailure(Handle<mirror::Class> klass) 121 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 122 if (VLOG_IS_ON(class_linker)) { 123 std::string temp; 124 LOG(INFO) << "Failed to initialize class " << klass->GetDescriptor(&temp) << " from " 125 << klass->GetLocation() << "\n" << Thread::Current()->GetException()->Dump(); 126 } 127} 128 129static void WrapExceptionInInitializer(Handle<mirror::Class> klass) 130 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 131 Thread* self = Thread::Current(); 132 JNIEnv* env = self->GetJniEnv(); 133 134 ScopedLocalRef<jthrowable> cause(env, env->ExceptionOccurred()); 135 CHECK(cause.get() != nullptr); 136 137 env->ExceptionClear(); 138 bool is_error = env->IsInstanceOf(cause.get(), WellKnownClasses::java_lang_Error); 139 env->Throw(cause.get()); 140 141 // We only wrap non-Error exceptions; an Error can just be used as-is. 142 if (!is_error) { 143 self->ThrowNewWrappedException("Ljava/lang/ExceptionInInitializerError;", nullptr); 144 } 145 VlogClassInitializationFailure(klass); 146} 147 148// Gap between two fields in object layout. 149struct FieldGap { 150 uint32_t start_offset; // The offset from the start of the object. 151 uint32_t size; // The gap size of 1, 2, or 4 bytes. 152}; 153struct FieldGapsComparator { 154 explicit FieldGapsComparator() { 155 } 156 bool operator() (const FieldGap& lhs, const FieldGap& rhs) 157 NO_THREAD_SAFETY_ANALYSIS { 158 // Sort by gap size, largest first. Secondary sort by starting offset. 159 return lhs.size > rhs.size || (lhs.size == rhs.size && lhs.start_offset < rhs.start_offset); 160 } 161}; 162typedef std::priority_queue<FieldGap, std::vector<FieldGap>, FieldGapsComparator> FieldGaps; 163 164// Adds largest aligned gaps to queue of gaps. 165static void AddFieldGap(uint32_t gap_start, uint32_t gap_end, FieldGaps* gaps) { 166 DCHECK(gaps != nullptr); 167 168 uint32_t current_offset = gap_start; 169 while (current_offset != gap_end) { 170 size_t remaining = gap_end - current_offset; 171 if (remaining >= sizeof(uint32_t) && IsAligned<4>(current_offset)) { 172 gaps->push(FieldGap {current_offset, sizeof(uint32_t)}); 173 current_offset += sizeof(uint32_t); 174 } else if (remaining >= sizeof(uint16_t) && IsAligned<2>(current_offset)) { 175 gaps->push(FieldGap {current_offset, sizeof(uint16_t)}); 176 current_offset += sizeof(uint16_t); 177 } else { 178 gaps->push(FieldGap {current_offset, sizeof(uint8_t)}); 179 current_offset += sizeof(uint8_t); 180 } 181 DCHECK_LE(current_offset, gap_end) << "Overran gap"; 182 } 183} 184// Shuffle fields forward, making use of gaps whenever possible. 185template<int n> 186static void ShuffleForward(size_t* current_field_idx, 187 MemberOffset* field_offset, 188 std::deque<mirror::ArtField*>* grouped_and_sorted_fields, 189 FieldGaps* gaps) 190 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 191 DCHECK(current_field_idx != nullptr); 192 DCHECK(grouped_and_sorted_fields != nullptr); 193 DCHECK(gaps != nullptr); 194 DCHECK(field_offset != nullptr); 195 196 DCHECK(IsPowerOfTwo(n)); 197 while (!grouped_and_sorted_fields->empty()) { 198 mirror::ArtField* field = grouped_and_sorted_fields->front(); 199 Primitive::Type type = field->GetTypeAsPrimitiveType(); 200 if (Primitive::ComponentSize(type) < n) { 201 break; 202 } 203 if (!IsAligned<n>(field_offset->Uint32Value())) { 204 MemberOffset old_offset = *field_offset; 205 *field_offset = MemberOffset(RoundUp(field_offset->Uint32Value(), n)); 206 AddFieldGap(old_offset.Uint32Value(), field_offset->Uint32Value(), gaps); 207 } 208 CHECK(type != Primitive::kPrimNot) << PrettyField(field); // should be primitive types 209 grouped_and_sorted_fields->pop_front(); 210 if (!gaps->empty() && gaps->top().size >= n) { 211 FieldGap gap = gaps->top(); 212 gaps->pop(); 213 DCHECK(IsAligned<n>(gap.start_offset)); 214 field->SetOffset(MemberOffset(gap.start_offset)); 215 if (gap.size > n) { 216 AddFieldGap(gap.start_offset + n, gap.start_offset + gap.size, gaps); 217 } 218 } else { 219 DCHECK(IsAligned<n>(field_offset->Uint32Value())); 220 field->SetOffset(*field_offset); 221 *field_offset = MemberOffset(field_offset->Uint32Value() + n); 222 } 223 ++(*current_field_idx); 224 } 225} 226 227ClassLinker::ClassLinker(InternTable* intern_table) 228 // dex_lock_ is recursive as it may be used in stack dumping. 229 : dex_lock_("ClassLinker dex lock", kDefaultMutexLevel), 230 dex_cache_image_class_lookup_required_(false), 231 failed_dex_cache_class_lookups_(0), 232 class_roots_(nullptr), 233 array_iftable_(nullptr), 234 find_array_class_cache_next_victim_(0), 235 init_done_(false), 236 log_new_dex_caches_roots_(false), 237 log_new_class_table_roots_(false), 238 intern_table_(intern_table), 239 quick_resolution_trampoline_(nullptr), 240 quick_imt_conflict_trampoline_(nullptr), 241 quick_generic_jni_trampoline_(nullptr), 242 quick_to_interpreter_bridge_trampoline_(nullptr), 243 image_pointer_size_(sizeof(void*)) { 244 memset(find_array_class_cache_, 0, kFindArrayCacheSize * sizeof(mirror::Class*)); 245} 246 247void ClassLinker::InitWithoutImage(std::vector<std::unique_ptr<const DexFile>> boot_class_path) { 248 VLOG(startup) << "ClassLinker::Init"; 249 CHECK(!Runtime::Current()->GetHeap()->HasImageSpace()) << "Runtime has image. We should use it."; 250 251 CHECK(!init_done_); 252 253 // java_lang_Class comes first, it's needed for AllocClass 254 Thread* self = Thread::Current(); 255 gc::Heap* heap = Runtime::Current()->GetHeap(); 256 // The GC can't handle an object with a null class since we can't get the size of this object. 257 heap->IncrementDisableMovingGC(self); 258 StackHandleScope<64> hs(self); // 64 is picked arbitrarily. 259 Handle<mirror::Class> java_lang_Class(hs.NewHandle(down_cast<mirror::Class*>( 260 heap->AllocNonMovableObject<true>(self, nullptr, 261 mirror::Class::ClassClassSize(), 262 VoidFunctor())))); 263 CHECK(java_lang_Class.Get() != nullptr); 264 mirror::Class::SetClassClass(java_lang_Class.Get()); 265 java_lang_Class->SetClass(java_lang_Class.Get()); 266 if (kUseBakerOrBrooksReadBarrier) { 267 java_lang_Class->AssertReadBarrierPointer(); 268 } 269 java_lang_Class->SetClassSize(mirror::Class::ClassClassSize()); 270 java_lang_Class->SetPrimitiveType(Primitive::kPrimNot); 271 heap->DecrementDisableMovingGC(self); 272 // AllocClass(mirror::Class*) can now be used 273 274 // Class[] is used for reflection support. 275 Handle<mirror::Class> class_array_class(hs.NewHandle( 276 AllocClass(self, java_lang_Class.Get(), mirror::ObjectArray<mirror::Class>::ClassSize()))); 277 class_array_class->SetComponentType(java_lang_Class.Get()); 278 279 // java_lang_Object comes next so that object_array_class can be created. 280 Handle<mirror::Class> java_lang_Object(hs.NewHandle( 281 AllocClass(self, java_lang_Class.Get(), mirror::Object::ClassSize()))); 282 CHECK(java_lang_Object.Get() != nullptr); 283 // backfill Object as the super class of Class. 284 java_lang_Class->SetSuperClass(java_lang_Object.Get()); 285 mirror::Class::SetStatus(java_lang_Object, mirror::Class::kStatusLoaded, self); 286 287 // Object[] next to hold class roots. 288 Handle<mirror::Class> object_array_class(hs.NewHandle( 289 AllocClass(self, java_lang_Class.Get(), mirror::ObjectArray<mirror::Object>::ClassSize()))); 290 object_array_class->SetComponentType(java_lang_Object.Get()); 291 292 // Setup the char (primitive) class to be used for char[]. 293 Handle<mirror::Class> char_class(hs.NewHandle( 294 AllocClass(self, java_lang_Class.Get(), mirror::Class::PrimitiveClassSize()))); 295 // The primitive char class won't be initialized by 296 // InitializePrimitiveClass until line 459, but strings (and 297 // internal char arrays) will be allocated before that and the 298 // component size, which is computed from the primitive type, needs 299 // to be set here. 300 char_class->SetPrimitiveType(Primitive::kPrimChar); 301 302 // Setup the char[] class to be used for String. 303 Handle<mirror::Class> char_array_class(hs.NewHandle( 304 AllocClass(self, java_lang_Class.Get(), 305 mirror::Array::ClassSize()))); 306 char_array_class->SetComponentType(char_class.Get()); 307 mirror::CharArray::SetArrayClass(char_array_class.Get()); 308 309 // Setup String. 310 Handle<mirror::Class> java_lang_String(hs.NewHandle( 311 AllocClass(self, java_lang_Class.Get(), mirror::String::ClassSize()))); 312 mirror::String::SetClass(java_lang_String.Get()); 313 java_lang_String->SetObjectSize(mirror::String::InstanceSize()); 314 mirror::Class::SetStatus(java_lang_String, mirror::Class::kStatusResolved, self); 315 316 // Setup Reference. 317 Handle<mirror::Class> java_lang_ref_Reference(hs.NewHandle( 318 AllocClass(self, java_lang_Class.Get(), mirror::Reference::ClassSize()))); 319 mirror::Reference::SetClass(java_lang_ref_Reference.Get()); 320 java_lang_ref_Reference->SetObjectSize(mirror::Reference::InstanceSize()); 321 mirror::Class::SetStatus(java_lang_ref_Reference, mirror::Class::kStatusResolved, self); 322 323 // Create storage for root classes, save away our work so far (requires descriptors). 324 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class> >( 325 mirror::ObjectArray<mirror::Class>::Alloc(self, object_array_class.Get(), 326 kClassRootsMax)); 327 CHECK(!class_roots_.IsNull()); 328 SetClassRoot(kJavaLangClass, java_lang_Class.Get()); 329 SetClassRoot(kJavaLangObject, java_lang_Object.Get()); 330 SetClassRoot(kClassArrayClass, class_array_class.Get()); 331 SetClassRoot(kObjectArrayClass, object_array_class.Get()); 332 SetClassRoot(kCharArrayClass, char_array_class.Get()); 333 SetClassRoot(kJavaLangString, java_lang_String.Get()); 334 SetClassRoot(kJavaLangRefReference, java_lang_ref_Reference.Get()); 335 336 // Setup the primitive type classes. 337 SetClassRoot(kPrimitiveBoolean, CreatePrimitiveClass(self, Primitive::kPrimBoolean)); 338 SetClassRoot(kPrimitiveByte, CreatePrimitiveClass(self, Primitive::kPrimByte)); 339 SetClassRoot(kPrimitiveShort, CreatePrimitiveClass(self, Primitive::kPrimShort)); 340 SetClassRoot(kPrimitiveInt, CreatePrimitiveClass(self, Primitive::kPrimInt)); 341 SetClassRoot(kPrimitiveLong, CreatePrimitiveClass(self, Primitive::kPrimLong)); 342 SetClassRoot(kPrimitiveFloat, CreatePrimitiveClass(self, Primitive::kPrimFloat)); 343 SetClassRoot(kPrimitiveDouble, CreatePrimitiveClass(self, Primitive::kPrimDouble)); 344 SetClassRoot(kPrimitiveVoid, CreatePrimitiveClass(self, Primitive::kPrimVoid)); 345 346 // Create array interface entries to populate once we can load system classes. 347 array_iftable_ = GcRoot<mirror::IfTable>(AllocIfTable(self, 2)); 348 349 // Create int array type for AllocDexCache (done in AppendToBootClassPath). 350 Handle<mirror::Class> int_array_class(hs.NewHandle( 351 AllocClass(self, java_lang_Class.Get(), mirror::Array::ClassSize()))); 352 int_array_class->SetComponentType(GetClassRoot(kPrimitiveInt)); 353 mirror::IntArray::SetArrayClass(int_array_class.Get()); 354 SetClassRoot(kIntArrayClass, int_array_class.Get()); 355 356 // now that these are registered, we can use AllocClass() and AllocObjectArray 357 358 // Set up DexCache. This cannot be done later since AppendToBootClassPath calls AllocDexCache. 359 Handle<mirror::Class> java_lang_DexCache(hs.NewHandle( 360 AllocClass(self, java_lang_Class.Get(), mirror::DexCache::ClassSize()))); 361 SetClassRoot(kJavaLangDexCache, java_lang_DexCache.Get()); 362 java_lang_DexCache->SetObjectSize(mirror::DexCache::InstanceSize()); 363 mirror::Class::SetStatus(java_lang_DexCache, mirror::Class::kStatusResolved, self); 364 365 // Constructor, Field, Method, and AbstractMethod are necessary so 366 // that FindClass can link members. 367 Handle<mirror::Class> java_lang_reflect_ArtField(hs.NewHandle( 368 AllocClass(self, java_lang_Class.Get(), mirror::ArtField::ClassSize()))); 369 CHECK(java_lang_reflect_ArtField.Get() != nullptr); 370 java_lang_reflect_ArtField->SetObjectSize(mirror::ArtField::InstanceSize()); 371 SetClassRoot(kJavaLangReflectArtField, java_lang_reflect_ArtField.Get()); 372 mirror::Class::SetStatus(java_lang_reflect_ArtField, mirror::Class::kStatusResolved, self); 373 mirror::ArtField::SetClass(java_lang_reflect_ArtField.Get()); 374 375 Handle<mirror::Class> java_lang_reflect_ArtMethod(hs.NewHandle( 376 AllocClass(self, java_lang_Class.Get(), mirror::ArtMethod::ClassSize()))); 377 CHECK(java_lang_reflect_ArtMethod.Get() != nullptr); 378 size_t pointer_size = GetInstructionSetPointerSize(Runtime::Current()->GetInstructionSet()); 379 java_lang_reflect_ArtMethod->SetObjectSize(mirror::ArtMethod::InstanceSize(pointer_size)); 380 SetClassRoot(kJavaLangReflectArtMethod, java_lang_reflect_ArtMethod.Get()); 381 mirror::Class::SetStatus(java_lang_reflect_ArtMethod, mirror::Class::kStatusResolved, self); 382 mirror::ArtMethod::SetClass(java_lang_reflect_ArtMethod.Get()); 383 384 // Set up array classes for string, field, method 385 Handle<mirror::Class> object_array_string(hs.NewHandle( 386 AllocClass(self, java_lang_Class.Get(), 387 mirror::ObjectArray<mirror::String>::ClassSize()))); 388 object_array_string->SetComponentType(java_lang_String.Get()); 389 SetClassRoot(kJavaLangStringArrayClass, object_array_string.Get()); 390 391 Handle<mirror::Class> object_array_art_method(hs.NewHandle( 392 AllocClass(self, java_lang_Class.Get(), 393 mirror::ObjectArray<mirror::ArtMethod>::ClassSize()))); 394 object_array_art_method->SetComponentType(java_lang_reflect_ArtMethod.Get()); 395 SetClassRoot(kJavaLangReflectArtMethodArrayClass, object_array_art_method.Get()); 396 397 Handle<mirror::Class> object_array_art_field(hs.NewHandle( 398 AllocClass(self, java_lang_Class.Get(), 399 mirror::ObjectArray<mirror::ArtField>::ClassSize()))); 400 object_array_art_field->SetComponentType(java_lang_reflect_ArtField.Get()); 401 SetClassRoot(kJavaLangReflectArtFieldArrayClass, object_array_art_field.Get()); 402 403 // Setup boot_class_path_ and register class_path now that we can use AllocObjectArray to create 404 // DexCache instances. Needs to be after String, Field, Method arrays since AllocDexCache uses 405 // these roots. 406 CHECK_NE(0U, boot_class_path.size()); 407 for (auto& dex_file : boot_class_path) { 408 CHECK(dex_file.get() != nullptr); 409 AppendToBootClassPath(self, *dex_file); 410 opened_dex_files_.push_back(std::move(dex_file)); 411 } 412 413 // now we can use FindSystemClass 414 415 // run char class through InitializePrimitiveClass to finish init 416 InitializePrimitiveClass(char_class.Get(), Primitive::kPrimChar); 417 SetClassRoot(kPrimitiveChar, char_class.Get()); // needs descriptor 418 419 // Create runtime resolution and imt conflict methods. Also setup the default imt. 420 Runtime* runtime = Runtime::Current(); 421 runtime->SetResolutionMethod(runtime->CreateResolutionMethod()); 422 runtime->SetImtConflictMethod(runtime->CreateImtConflictMethod()); 423 runtime->SetImtUnimplementedMethod(runtime->CreateImtConflictMethod()); 424 runtime->SetDefaultImt(runtime->CreateDefaultImt(this)); 425 426 // Set up GenericJNI entrypoint. That is mainly a hack for common_compiler_test.h so that 427 // we do not need friend classes or a publicly exposed setter. 428 quick_generic_jni_trampoline_ = GetQuickGenericJniStub(); 429 if (!runtime->IsAotCompiler()) { 430 // We need to set up the generic trampolines since we don't have an image. 431 quick_resolution_trampoline_ = GetQuickResolutionStub(); 432 quick_imt_conflict_trampoline_ = GetQuickImtConflictStub(); 433 quick_to_interpreter_bridge_trampoline_ = GetQuickToInterpreterBridge(); 434 } 435 436 // Object, String and DexCache need to be rerun through FindSystemClass to finish init 437 mirror::Class::SetStatus(java_lang_Object, mirror::Class::kStatusNotReady, self); 438 mirror::Class* Object_class = FindSystemClass(self, "Ljava/lang/Object;"); 439 CHECK_EQ(java_lang_Object.Get(), Object_class); 440 CHECK_EQ(java_lang_Object->GetObjectSize(), mirror::Object::InstanceSize()); 441 mirror::Class::SetStatus(java_lang_String, mirror::Class::kStatusNotReady, self); 442 mirror::Class* String_class = FindSystemClass(self, "Ljava/lang/String;"); 443 std::ostringstream os1, os2; 444 java_lang_String->DumpClass(os1, mirror::Class::kDumpClassFullDetail); 445 String_class->DumpClass(os2, mirror::Class::kDumpClassFullDetail); 446 CHECK_EQ(java_lang_String.Get(), String_class) << os1.str() << "\n\n" << os2.str(); 447 CHECK_EQ(java_lang_String->GetObjectSize(), mirror::String::InstanceSize()); 448 mirror::Class::SetStatus(java_lang_DexCache, mirror::Class::kStatusNotReady, self); 449 mirror::Class* DexCache_class = FindSystemClass(self, "Ljava/lang/DexCache;"); 450 CHECK_EQ(java_lang_String.Get(), String_class); 451 CHECK_EQ(java_lang_DexCache.Get(), DexCache_class); 452 CHECK_EQ(java_lang_DexCache->GetObjectSize(), mirror::DexCache::InstanceSize()); 453 454 // Setup the primitive array type classes - can't be done until Object has a vtable. 455 SetClassRoot(kBooleanArrayClass, FindSystemClass(self, "[Z")); 456 mirror::BooleanArray::SetArrayClass(GetClassRoot(kBooleanArrayClass)); 457 458 SetClassRoot(kByteArrayClass, FindSystemClass(self, "[B")); 459 mirror::ByteArray::SetArrayClass(GetClassRoot(kByteArrayClass)); 460 461 mirror::Class* found_char_array_class = FindSystemClass(self, "[C"); 462 CHECK_EQ(char_array_class.Get(), found_char_array_class); 463 464 SetClassRoot(kShortArrayClass, FindSystemClass(self, "[S")); 465 mirror::ShortArray::SetArrayClass(GetClassRoot(kShortArrayClass)); 466 467 mirror::Class* found_int_array_class = FindSystemClass(self, "[I"); 468 CHECK_EQ(int_array_class.Get(), found_int_array_class); 469 470 SetClassRoot(kLongArrayClass, FindSystemClass(self, "[J")); 471 mirror::LongArray::SetArrayClass(GetClassRoot(kLongArrayClass)); 472 473 SetClassRoot(kFloatArrayClass, FindSystemClass(self, "[F")); 474 mirror::FloatArray::SetArrayClass(GetClassRoot(kFloatArrayClass)); 475 476 SetClassRoot(kDoubleArrayClass, FindSystemClass(self, "[D")); 477 mirror::DoubleArray::SetArrayClass(GetClassRoot(kDoubleArrayClass)); 478 479 mirror::Class* found_class_array_class = FindSystemClass(self, "[Ljava/lang/Class;"); 480 CHECK_EQ(class_array_class.Get(), found_class_array_class); 481 482 mirror::Class* found_object_array_class = FindSystemClass(self, "[Ljava/lang/Object;"); 483 CHECK_EQ(object_array_class.Get(), found_object_array_class); 484 485 // Setup the single, global copy of "iftable". 486 mirror::Class* java_lang_Cloneable = FindSystemClass(self, "Ljava/lang/Cloneable;"); 487 CHECK(java_lang_Cloneable != nullptr); 488 mirror::Class* java_io_Serializable = FindSystemClass(self, "Ljava/io/Serializable;"); 489 CHECK(java_io_Serializable != nullptr); 490 // We assume that Cloneable/Serializable don't have superinterfaces -- normally we'd have to 491 // crawl up and explicitly list all of the supers as well. 492 { 493 mirror::IfTable* array_iftable = array_iftable_.Read(); 494 array_iftable->SetInterface(0, java_lang_Cloneable); 495 array_iftable->SetInterface(1, java_io_Serializable); 496 } 497 498 // Sanity check Class[] and Object[]'s interfaces. 499 CHECK_EQ(java_lang_Cloneable, mirror::Class::GetDirectInterface(self, class_array_class, 0)); 500 CHECK_EQ(java_io_Serializable, mirror::Class::GetDirectInterface(self, class_array_class, 1)); 501 CHECK_EQ(java_lang_Cloneable, mirror::Class::GetDirectInterface(self, object_array_class, 0)); 502 CHECK_EQ(java_io_Serializable, mirror::Class::GetDirectInterface(self, object_array_class, 1)); 503 // Run Class, ArtField, and ArtMethod through FindSystemClass. This initializes their 504 // dex_cache_ fields and register them in class_table_. 505 mirror::Class* Class_class = FindSystemClass(self, "Ljava/lang/Class;"); 506 CHECK_EQ(java_lang_Class.Get(), Class_class); 507 508 mirror::Class::SetStatus(java_lang_reflect_ArtMethod, mirror::Class::kStatusNotReady, self); 509 mirror::Class* Art_method_class = FindSystemClass(self, "Ljava/lang/reflect/ArtMethod;"); 510 CHECK_EQ(java_lang_reflect_ArtMethod.Get(), Art_method_class); 511 512 mirror::Class::SetStatus(java_lang_reflect_ArtField, mirror::Class::kStatusNotReady, self); 513 mirror::Class* Art_field_class = FindSystemClass(self, "Ljava/lang/reflect/ArtField;"); 514 CHECK_EQ(java_lang_reflect_ArtField.Get(), Art_field_class); 515 516 mirror::Class* String_array_class = 517 FindSystemClass(self, GetClassRootDescriptor(kJavaLangStringArrayClass)); 518 CHECK_EQ(object_array_string.Get(), String_array_class); 519 520 mirror::Class* Art_method_array_class = 521 FindSystemClass(self, GetClassRootDescriptor(kJavaLangReflectArtMethodArrayClass)); 522 CHECK_EQ(object_array_art_method.Get(), Art_method_array_class); 523 524 mirror::Class* Art_field_array_class = 525 FindSystemClass(self, GetClassRootDescriptor(kJavaLangReflectArtFieldArrayClass)); 526 CHECK_EQ(object_array_art_field.Get(), Art_field_array_class); 527 528 // End of special init trickery, subsequent classes may be loaded via FindSystemClass. 529 530 // Create java.lang.reflect.Proxy root. 531 mirror::Class* java_lang_reflect_Proxy = FindSystemClass(self, "Ljava/lang/reflect/Proxy;"); 532 SetClassRoot(kJavaLangReflectProxy, java_lang_reflect_Proxy); 533 534 // java.lang.ref classes need to be specially flagged, but otherwise are normal classes 535 // finish initializing Reference class 536 mirror::Class::SetStatus(java_lang_ref_Reference, mirror::Class::kStatusNotReady, self); 537 mirror::Class* Reference_class = FindSystemClass(self, "Ljava/lang/ref/Reference;"); 538 CHECK_EQ(java_lang_ref_Reference.Get(), Reference_class); 539 CHECK_EQ(java_lang_ref_Reference->GetObjectSize(), mirror::Reference::InstanceSize()); 540 CHECK_EQ(java_lang_ref_Reference->GetClassSize(), mirror::Reference::ClassSize()); 541 mirror::Class* java_lang_ref_FinalizerReference = 542 FindSystemClass(self, "Ljava/lang/ref/FinalizerReference;"); 543 java_lang_ref_FinalizerReference->SetAccessFlags( 544 java_lang_ref_FinalizerReference->GetAccessFlags() | 545 kAccClassIsReference | kAccClassIsFinalizerReference); 546 mirror::Class* java_lang_ref_PhantomReference = 547 FindSystemClass(self, "Ljava/lang/ref/PhantomReference;"); 548 java_lang_ref_PhantomReference->SetAccessFlags( 549 java_lang_ref_PhantomReference->GetAccessFlags() | 550 kAccClassIsReference | kAccClassIsPhantomReference); 551 mirror::Class* java_lang_ref_SoftReference = 552 FindSystemClass(self, "Ljava/lang/ref/SoftReference;"); 553 java_lang_ref_SoftReference->SetAccessFlags( 554 java_lang_ref_SoftReference->GetAccessFlags() | kAccClassIsReference); 555 mirror::Class* java_lang_ref_WeakReference = 556 FindSystemClass(self, "Ljava/lang/ref/WeakReference;"); 557 java_lang_ref_WeakReference->SetAccessFlags( 558 java_lang_ref_WeakReference->GetAccessFlags() | 559 kAccClassIsReference | kAccClassIsWeakReference); 560 561 // Setup the ClassLoader, verifying the object_size_. 562 mirror::Class* java_lang_ClassLoader = FindSystemClass(self, "Ljava/lang/ClassLoader;"); 563 CHECK_EQ(java_lang_ClassLoader->GetObjectSize(), mirror::ClassLoader::InstanceSize()); 564 SetClassRoot(kJavaLangClassLoader, java_lang_ClassLoader); 565 566 // Set up java.lang.Throwable, java.lang.ClassNotFoundException, and 567 // java.lang.StackTraceElement as a convenience. 568 SetClassRoot(kJavaLangThrowable, FindSystemClass(self, "Ljava/lang/Throwable;")); 569 mirror::Throwable::SetClass(GetClassRoot(kJavaLangThrowable)); 570 SetClassRoot(kJavaLangClassNotFoundException, 571 FindSystemClass(self, "Ljava/lang/ClassNotFoundException;")); 572 SetClassRoot(kJavaLangStackTraceElement, FindSystemClass(self, "Ljava/lang/StackTraceElement;")); 573 SetClassRoot(kJavaLangStackTraceElementArrayClass, 574 FindSystemClass(self, "[Ljava/lang/StackTraceElement;")); 575 mirror::StackTraceElement::SetClass(GetClassRoot(kJavaLangStackTraceElement)); 576 577 // Ensure void type is resolved in the core's dex cache so java.lang.Void is correctly 578 // initialized. 579 { 580 const DexFile& dex_file = java_lang_Object->GetDexFile(); 581 const DexFile::StringId* void_string_id = dex_file.FindStringId("V"); 582 CHECK(void_string_id != nullptr); 583 uint32_t void_string_index = dex_file.GetIndexForStringId(*void_string_id); 584 const DexFile::TypeId* void_type_id = dex_file.FindTypeId(void_string_index); 585 CHECK(void_type_id != nullptr); 586 uint16_t void_type_idx = dex_file.GetIndexForTypeId(*void_type_id); 587 // Now we resolve void type so the dex cache contains it. We use java.lang.Object class 588 // as referrer so the used dex cache is core's one. 589 mirror::Class* resolved_type = ResolveType(dex_file, void_type_idx, java_lang_Object.Get()); 590 CHECK_EQ(resolved_type, GetClassRoot(kPrimitiveVoid)); 591 self->AssertNoPendingException(); 592 } 593 594 FinishInit(self); 595 596 VLOG(startup) << "ClassLinker::InitFromCompiler exiting"; 597} 598 599void ClassLinker::FinishInit(Thread* self) { 600 VLOG(startup) << "ClassLinker::FinishInit entering"; 601 602 // Let the heap know some key offsets into java.lang.ref instances 603 // Note: we hard code the field indexes here rather than using FindInstanceField 604 // as the types of the field can't be resolved prior to the runtime being 605 // fully initialized 606 mirror::Class* java_lang_ref_Reference = GetClassRoot(kJavaLangRefReference); 607 mirror::Class* java_lang_ref_FinalizerReference = 608 FindSystemClass(self, "Ljava/lang/ref/FinalizerReference;"); 609 610 mirror::ArtField* pendingNext = java_lang_ref_Reference->GetInstanceField(0); 611 CHECK_STREQ(pendingNext->GetName(), "pendingNext"); 612 CHECK_STREQ(pendingNext->GetTypeDescriptor(), "Ljava/lang/ref/Reference;"); 613 614 mirror::ArtField* queue = java_lang_ref_Reference->GetInstanceField(1); 615 CHECK_STREQ(queue->GetName(), "queue"); 616 CHECK_STREQ(queue->GetTypeDescriptor(), "Ljava/lang/ref/ReferenceQueue;"); 617 618 mirror::ArtField* queueNext = java_lang_ref_Reference->GetInstanceField(2); 619 CHECK_STREQ(queueNext->GetName(), "queueNext"); 620 CHECK_STREQ(queueNext->GetTypeDescriptor(), "Ljava/lang/ref/Reference;"); 621 622 mirror::ArtField* referent = java_lang_ref_Reference->GetInstanceField(3); 623 CHECK_STREQ(referent->GetName(), "referent"); 624 CHECK_STREQ(referent->GetTypeDescriptor(), "Ljava/lang/Object;"); 625 626 mirror::ArtField* zombie = java_lang_ref_FinalizerReference->GetInstanceField(2); 627 CHECK_STREQ(zombie->GetName(), "zombie"); 628 CHECK_STREQ(zombie->GetTypeDescriptor(), "Ljava/lang/Object;"); 629 630 // ensure all class_roots_ are initialized 631 for (size_t i = 0; i < kClassRootsMax; i++) { 632 ClassRoot class_root = static_cast<ClassRoot>(i); 633 mirror::Class* klass = GetClassRoot(class_root); 634 CHECK(klass != nullptr); 635 DCHECK(klass->IsArrayClass() || klass->IsPrimitive() || klass->GetDexCache() != nullptr); 636 // note SetClassRoot does additional validation. 637 // if possible add new checks there to catch errors early 638 } 639 640 CHECK(!array_iftable_.IsNull()); 641 642 // disable the slow paths in FindClass and CreatePrimitiveClass now 643 // that Object, Class, and Object[] are setup 644 init_done_ = true; 645 646 VLOG(startup) << "ClassLinker::FinishInit exiting"; 647} 648 649void ClassLinker::RunRootClinits() { 650 Thread* self = Thread::Current(); 651 for (size_t i = 0; i < ClassLinker::kClassRootsMax; ++i) { 652 mirror::Class* c = GetClassRoot(ClassRoot(i)); 653 if (!c->IsArrayClass() && !c->IsPrimitive()) { 654 StackHandleScope<1> hs(self); 655 Handle<mirror::Class> h_class(hs.NewHandle(GetClassRoot(ClassRoot(i)))); 656 EnsureInitialized(self, h_class, true, true); 657 self->AssertNoPendingException(); 658 } 659 } 660} 661 662const OatFile* ClassLinker::RegisterOatFile(const OatFile* oat_file) { 663 WriterMutexLock mu(Thread::Current(), dex_lock_); 664 if (kIsDebugBuild) { 665 for (size_t i = 0; i < oat_files_.size(); ++i) { 666 CHECK_NE(oat_file, oat_files_[i]) << oat_file->GetLocation(); 667 } 668 } 669 VLOG(class_linker) << "Registering " << oat_file->GetLocation(); 670 oat_files_.push_back(oat_file); 671 return oat_file; 672} 673 674OatFile& ClassLinker::GetImageOatFile(gc::space::ImageSpace* space) { 675 VLOG(startup) << "ClassLinker::GetImageOatFile entering"; 676 OatFile* oat_file = space->ReleaseOatFile(); 677 CHECK_EQ(RegisterOatFile(oat_file), oat_file); 678 VLOG(startup) << "ClassLinker::GetImageOatFile exiting"; 679 return *oat_file; 680} 681 682const OatFile::OatDexFile* ClassLinker::FindOpenedOatDexFileForDexFile(const DexFile& dex_file) { 683 const char* dex_location = dex_file.GetLocation().c_str(); 684 uint32_t dex_location_checksum = dex_file.GetLocationChecksum(); 685 return FindOpenedOatDexFile(nullptr, dex_location, &dex_location_checksum); 686} 687 688const OatFile::OatDexFile* ClassLinker::FindOpenedOatDexFile(const char* oat_location, 689 const char* dex_location, 690 const uint32_t* dex_location_checksum) { 691 ReaderMutexLock mu(Thread::Current(), dex_lock_); 692 for (const OatFile* oat_file : oat_files_) { 693 DCHECK(oat_file != nullptr); 694 695 if (oat_location != nullptr) { 696 if (oat_file->GetLocation() != oat_location) { 697 continue; 698 } 699 } 700 701 const OatFile::OatDexFile* oat_dex_file = oat_file->GetOatDexFile(dex_location, 702 dex_location_checksum, 703 false); 704 if (oat_dex_file != nullptr) { 705 return oat_dex_file; 706 } 707 } 708 return nullptr; 709} 710 711std::vector<std::unique_ptr<const DexFile>> ClassLinker::OpenDexFilesFromOat( 712 const char* dex_location, const char* oat_location, 713 std::vector<std::string>* error_msgs) { 714 CHECK(error_msgs != nullptr); 715 716 // Verify we aren't holding the mutator lock, which could starve GC if we 717 // have to generate or relocate an oat file. 718 Locks::mutator_lock_->AssertNotHeld(Thread::Current()); 719 720 OatFileAssistant oat_file_assistant(dex_location, oat_location, kRuntimeISA, 721 !Runtime::Current()->IsAotCompiler()); 722 723 // Lock the target oat location to avoid races generating and loading the 724 // oat file. 725 std::string error_msg; 726 if (!oat_file_assistant.Lock(&error_msg)) { 727 // Don't worry too much if this fails. If it does fail, it's unlikely we 728 // can generate an oat file anyway. 729 VLOG(class_linker) << "OatFileAssistant::Lock: " << error_msg; 730 } 731 732 // Check if we already have an up-to-date oat file open. 733 const OatFile* source_oat_file = nullptr; 734 { 735 ReaderMutexLock mu(Thread::Current(), dex_lock_); 736 for (const OatFile* oat_file : oat_files_) { 737 CHECK(oat_file != nullptr); 738 if (oat_file_assistant.GivenOatFileIsUpToDate(*oat_file)) { 739 source_oat_file = oat_file; 740 break; 741 } 742 } 743 } 744 745 // If we didn't have an up-to-date oat file open, try to load one from disk. 746 if (source_oat_file == nullptr) { 747 // Update the oat file on disk if we can. This may fail, but that's okay. 748 // Best effort is all that matters here. 749 if (!oat_file_assistant.MakeUpToDate(&error_msg)) { 750 LOG(WARNING) << error_msg; 751 } 752 753 // Get the oat file on disk. 754 std::unique_ptr<OatFile> oat_file = oat_file_assistant.GetBestOatFile(); 755 if (oat_file.get() != nullptr) { 756 source_oat_file = oat_file.release(); 757 RegisterOatFile(source_oat_file); 758 } 759 } 760 761 std::vector<std::unique_ptr<const DexFile>> dex_files; 762 763 // Load the dex files from the oat file. 764 if (source_oat_file != nullptr) { 765 dex_files = oat_file_assistant.LoadDexFiles(*source_oat_file, dex_location); 766 if (dex_files.empty()) { 767 error_msgs->push_back("Failed to open dex files from " 768 + source_oat_file->GetLocation()); 769 } 770 } 771 772 // Fall back to running out of the original dex file if we couldn't load any 773 // dex_files from the oat file. 774 if (dex_files.empty()) { 775 if (Runtime::Current()->IsDexFileFallbackEnabled()) { 776 if (!DexFile::Open(dex_location, dex_location, &error_msg, &dex_files)) { 777 LOG(WARNING) << error_msg; 778 error_msgs->push_back("Failed to open dex files from " 779 + std::string(dex_location)); 780 } 781 } else { 782 error_msgs->push_back("Fallback mode disabled, skipping dex files."); 783 } 784 } 785 return dex_files; 786} 787 788const OatFile* ClassLinker::FindOpenedOatFileFromOatLocation(const std::string& oat_location) { 789 ReaderMutexLock mu(Thread::Current(), dex_lock_); 790 for (size_t i = 0; i < oat_files_.size(); i++) { 791 const OatFile* oat_file = oat_files_[i]; 792 DCHECK(oat_file != nullptr); 793 if (oat_file->GetLocation() == oat_location) { 794 return oat_file; 795 } 796 } 797 return nullptr; 798} 799 800void ClassLinker::InitFromImageInterpretOnlyCallback(mirror::Object* obj, void* arg) { 801 ClassLinker* class_linker = reinterpret_cast<ClassLinker*>(arg); 802 DCHECK(obj != nullptr); 803 DCHECK(class_linker != nullptr); 804 if (obj->IsArtMethod()) { 805 mirror::ArtMethod* method = obj->AsArtMethod(); 806 if (!method->IsNative()) { 807 const size_t pointer_size = class_linker->image_pointer_size_; 808 method->SetEntryPointFromInterpreterPtrSize(artInterpreterToInterpreterBridge, pointer_size); 809 if (!method->IsRuntimeMethod() && method != Runtime::Current()->GetResolutionMethod()) { 810 method->SetEntryPointFromQuickCompiledCodePtrSize(GetQuickToInterpreterBridge(), 811 pointer_size); 812 } 813 } 814 } 815} 816 817void ClassLinker::InitFromImage() { 818 VLOG(startup) << "ClassLinker::InitFromImage entering"; 819 CHECK(!init_done_); 820 821 Thread* self = Thread::Current(); 822 gc::Heap* heap = Runtime::Current()->GetHeap(); 823 gc::space::ImageSpace* space = heap->GetImageSpace(); 824 dex_cache_image_class_lookup_required_ = true; 825 CHECK(space != nullptr); 826 OatFile& oat_file = GetImageOatFile(space); 827 CHECK_EQ(oat_file.GetOatHeader().GetImageFileLocationOatChecksum(), 0U); 828 CHECK_EQ(oat_file.GetOatHeader().GetImageFileLocationOatDataBegin(), 0U); 829 const char* image_file_location = oat_file.GetOatHeader(). 830 GetStoreValueByKey(OatHeader::kImageLocationKey); 831 CHECK(image_file_location == nullptr || *image_file_location == 0); 832 quick_resolution_trampoline_ = oat_file.GetOatHeader().GetQuickResolutionTrampoline(); 833 quick_imt_conflict_trampoline_ = oat_file.GetOatHeader().GetQuickImtConflictTrampoline(); 834 quick_generic_jni_trampoline_ = oat_file.GetOatHeader().GetQuickGenericJniTrampoline(); 835 quick_to_interpreter_bridge_trampoline_ = oat_file.GetOatHeader().GetQuickToInterpreterBridge(); 836 mirror::Object* dex_caches_object = space->GetImageHeader().GetImageRoot(ImageHeader::kDexCaches); 837 mirror::ObjectArray<mirror::DexCache>* dex_caches = 838 dex_caches_object->AsObjectArray<mirror::DexCache>(); 839 840 StackHandleScope<1> hs(self); 841 Handle<mirror::ObjectArray<mirror::Class>> class_roots(hs.NewHandle( 842 space->GetImageHeader().GetImageRoot(ImageHeader::kClassRoots)-> 843 AsObjectArray<mirror::Class>())); 844 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class>>(class_roots.Get()); 845 846 // Special case of setting up the String class early so that we can test arbitrary objects 847 // as being Strings or not 848 mirror::String::SetClass(GetClassRoot(kJavaLangString)); 849 850 CHECK_EQ(oat_file.GetOatHeader().GetDexFileCount(), 851 static_cast<uint32_t>(dex_caches->GetLength())); 852 for (int32_t i = 0; i < dex_caches->GetLength(); i++) { 853 StackHandleScope<1> hs2(self); 854 Handle<mirror::DexCache> dex_cache(hs2.NewHandle(dex_caches->Get(i))); 855 const std::string& dex_file_location(dex_cache->GetLocation()->ToModifiedUtf8()); 856 const OatFile::OatDexFile* oat_dex_file = oat_file.GetOatDexFile(dex_file_location.c_str(), 857 nullptr); 858 CHECK(oat_dex_file != nullptr) << oat_file.GetLocation() << " " << dex_file_location; 859 std::string error_msg; 860 std::unique_ptr<const DexFile> dex_file = oat_dex_file->OpenDexFile(&error_msg); 861 if (dex_file.get() == nullptr) { 862 LOG(FATAL) << "Failed to open dex file " << dex_file_location 863 << " from within oat file " << oat_file.GetLocation() 864 << " error '" << error_msg << "'"; 865 UNREACHABLE(); 866 } 867 868 CHECK_EQ(dex_file->GetLocationChecksum(), oat_dex_file->GetDexFileLocationChecksum()); 869 870 AppendToBootClassPath(*dex_file.get(), dex_cache); 871 opened_dex_files_.push_back(std::move(dex_file)); 872 } 873 874 // Set classes on AbstractMethod early so that IsMethod tests can be performed during the live 875 // bitmap walk. 876 mirror::ArtMethod::SetClass(GetClassRoot(kJavaLangReflectArtMethod)); 877 size_t art_method_object_size = mirror::ArtMethod::GetJavaLangReflectArtMethod()->GetObjectSize(); 878 if (!Runtime::Current()->IsAotCompiler()) { 879 // Aot compiler supports having an image with a different pointer size than the runtime. This 880 // happens on the host for compile 32 bit tests since we use a 64 bit libart compiler. We may 881 // also use 32 bit dex2oat on a system with 64 bit apps. 882 CHECK_EQ(art_method_object_size, mirror::ArtMethod::InstanceSize(sizeof(void*))) 883 << sizeof(void*); 884 } 885 if (art_method_object_size == mirror::ArtMethod::InstanceSize(4)) { 886 image_pointer_size_ = 4; 887 } else { 888 CHECK_EQ(art_method_object_size, mirror::ArtMethod::InstanceSize(8)); 889 image_pointer_size_ = 8; 890 } 891 892 // Set entry point to interpreter if in InterpretOnly mode. 893 Runtime* runtime = Runtime::Current(); 894 if (!runtime->IsAotCompiler() && runtime->GetInstrumentation()->InterpretOnly()) { 895 heap->VisitObjects(InitFromImageInterpretOnlyCallback, this); 896 } 897 898 // reinit class_roots_ 899 mirror::Class::SetClassClass(class_roots->Get(kJavaLangClass)); 900 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class>>(class_roots.Get()); 901 902 // reinit array_iftable_ from any array class instance, they should be == 903 array_iftable_ = GcRoot<mirror::IfTable>(GetClassRoot(kObjectArrayClass)->GetIfTable()); 904 DCHECK_EQ(array_iftable_.Read(), GetClassRoot(kBooleanArrayClass)->GetIfTable()); 905 // String class root was set above 906 mirror::Reference::SetClass(GetClassRoot(kJavaLangRefReference)); 907 mirror::ArtField::SetClass(GetClassRoot(kJavaLangReflectArtField)); 908 mirror::BooleanArray::SetArrayClass(GetClassRoot(kBooleanArrayClass)); 909 mirror::ByteArray::SetArrayClass(GetClassRoot(kByteArrayClass)); 910 mirror::CharArray::SetArrayClass(GetClassRoot(kCharArrayClass)); 911 mirror::DoubleArray::SetArrayClass(GetClassRoot(kDoubleArrayClass)); 912 mirror::FloatArray::SetArrayClass(GetClassRoot(kFloatArrayClass)); 913 mirror::IntArray::SetArrayClass(GetClassRoot(kIntArrayClass)); 914 mirror::LongArray::SetArrayClass(GetClassRoot(kLongArrayClass)); 915 mirror::ShortArray::SetArrayClass(GetClassRoot(kShortArrayClass)); 916 mirror::Throwable::SetClass(GetClassRoot(kJavaLangThrowable)); 917 mirror::StackTraceElement::SetClass(GetClassRoot(kJavaLangStackTraceElement)); 918 919 FinishInit(self); 920 921 VLOG(startup) << "ClassLinker::InitFromImage exiting"; 922} 923 924void ClassLinker::VisitClassRoots(RootCallback* callback, void* arg, VisitRootFlags flags) { 925 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 926 if ((flags & kVisitRootFlagAllRoots) != 0) { 927 for (GcRoot<mirror::Class>& root : class_table_) { 928 root.VisitRoot(callback, arg, RootInfo(kRootStickyClass)); 929 } 930 for (GcRoot<mirror::Class>& root : pre_zygote_class_table_) { 931 root.VisitRoot(callback, arg, RootInfo(kRootStickyClass)); 932 } 933 } else if ((flags & kVisitRootFlagNewRoots) != 0) { 934 for (auto& root : new_class_roots_) { 935 mirror::Class* old_ref = root.Read<kWithoutReadBarrier>(); 936 root.VisitRoot(callback, arg, RootInfo(kRootStickyClass)); 937 mirror::Class* new_ref = root.Read<kWithoutReadBarrier>(); 938 if (UNLIKELY(new_ref != old_ref)) { 939 // Uh ohes, GC moved a root in the log. Need to search the class_table and update the 940 // corresponding object. This is slow, but luckily for us, this may only happen with a 941 // concurrent moving GC. 942 auto it = class_table_.Find(GcRoot<mirror::Class>(old_ref)); 943 DCHECK(it != class_table_.end()); 944 *it = GcRoot<mirror::Class>(new_ref); 945 } 946 } 947 } 948 if ((flags & kVisitRootFlagClearRootLog) != 0) { 949 new_class_roots_.clear(); 950 } 951 if ((flags & kVisitRootFlagStartLoggingNewRoots) != 0) { 952 log_new_class_table_roots_ = true; 953 } else if ((flags & kVisitRootFlagStopLoggingNewRoots) != 0) { 954 log_new_class_table_roots_ = false; 955 } 956 // We deliberately ignore the class roots in the image since we 957 // handle image roots by using the MS/CMS rescanning of dirty cards. 958} 959 960// Keep in sync with InitCallback. Anything we visit, we need to 961// reinit references to when reinitializing a ClassLinker from a 962// mapped image. 963void ClassLinker::VisitRoots(RootCallback* callback, void* arg, VisitRootFlags flags) { 964 class_roots_.VisitRoot(callback, arg, RootInfo(kRootVMInternal)); 965 Thread* self = Thread::Current(); 966 { 967 ReaderMutexLock mu(self, dex_lock_); 968 if ((flags & kVisitRootFlagAllRoots) != 0) { 969 for (GcRoot<mirror::DexCache>& dex_cache : dex_caches_) { 970 dex_cache.VisitRoot(callback, arg, RootInfo(kRootVMInternal)); 971 } 972 } else if ((flags & kVisitRootFlagNewRoots) != 0) { 973 for (size_t index : new_dex_cache_roots_) { 974 dex_caches_[index].VisitRoot(callback, arg, RootInfo(kRootVMInternal)); 975 } 976 } 977 if ((flags & kVisitRootFlagClearRootLog) != 0) { 978 new_dex_cache_roots_.clear(); 979 } 980 if ((flags & kVisitRootFlagStartLoggingNewRoots) != 0) { 981 log_new_dex_caches_roots_ = true; 982 } else if ((flags & kVisitRootFlagStopLoggingNewRoots) != 0) { 983 log_new_dex_caches_roots_ = false; 984 } 985 } 986 VisitClassRoots(callback, arg, flags); 987 array_iftable_.VisitRoot(callback, arg, RootInfo(kRootVMInternal)); 988 DCHECK(!array_iftable_.IsNull()); 989 for (size_t i = 0; i < kFindArrayCacheSize; ++i) { 990 find_array_class_cache_[i].VisitRootIfNonNull(callback, arg, RootInfo(kRootVMInternal)); 991 } 992} 993 994void ClassLinker::VisitClasses(ClassVisitor* visitor, void* arg) { 995 if (dex_cache_image_class_lookup_required_) { 996 MoveImageClassesToClassTable(); 997 } 998 // TODO: why isn't this a ReaderMutexLock? 999 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 1000 for (GcRoot<mirror::Class>& root : class_table_) { 1001 if (!visitor(root.Read(), arg)) { 1002 return; 1003 } 1004 } 1005 for (GcRoot<mirror::Class>& root : pre_zygote_class_table_) { 1006 if (!visitor(root.Read(), arg)) { 1007 return; 1008 } 1009 } 1010} 1011 1012static bool GetClassesVisitorSet(mirror::Class* c, void* arg) { 1013 std::set<mirror::Class*>* classes = reinterpret_cast<std::set<mirror::Class*>*>(arg); 1014 classes->insert(c); 1015 return true; 1016} 1017 1018struct GetClassesVisitorArrayArg { 1019 Handle<mirror::ObjectArray<mirror::Class>>* classes; 1020 int32_t index; 1021 bool success; 1022}; 1023 1024static bool GetClassesVisitorArray(mirror::Class* c, void* varg) 1025 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1026 GetClassesVisitorArrayArg* arg = reinterpret_cast<GetClassesVisitorArrayArg*>(varg); 1027 if (arg->index < (*arg->classes)->GetLength()) { 1028 (*arg->classes)->Set(arg->index, c); 1029 arg->index++; 1030 return true; 1031 } else { 1032 arg->success = false; 1033 return false; 1034 } 1035} 1036 1037void ClassLinker::VisitClassesWithoutClassesLock(ClassVisitor* visitor, void* arg) { 1038 // TODO: it may be possible to avoid secondary storage if we iterate over dex caches. The problem 1039 // is avoiding duplicates. 1040 if (!kMovingClasses) { 1041 std::set<mirror::Class*> classes; 1042 VisitClasses(GetClassesVisitorSet, &classes); 1043 for (mirror::Class* klass : classes) { 1044 if (!visitor(klass, arg)) { 1045 return; 1046 } 1047 } 1048 } else { 1049 Thread* self = Thread::Current(); 1050 StackHandleScope<1> hs(self); 1051 MutableHandle<mirror::ObjectArray<mirror::Class>> classes = 1052 hs.NewHandle<mirror::ObjectArray<mirror::Class>>(nullptr); 1053 GetClassesVisitorArrayArg local_arg; 1054 local_arg.classes = &classes; 1055 local_arg.success = false; 1056 // We size the array assuming classes won't be added to the class table during the visit. 1057 // If this assumption fails we iterate again. 1058 while (!local_arg.success) { 1059 size_t class_table_size; 1060 { 1061 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 1062 class_table_size = class_table_.Size() + pre_zygote_class_table_.Size(); 1063 } 1064 mirror::Class* class_type = mirror::Class::GetJavaLangClass(); 1065 mirror::Class* array_of_class = FindArrayClass(self, &class_type); 1066 classes.Assign( 1067 mirror::ObjectArray<mirror::Class>::Alloc(self, array_of_class, class_table_size)); 1068 CHECK(classes.Get() != nullptr); // OOME. 1069 local_arg.index = 0; 1070 local_arg.success = true; 1071 VisitClasses(GetClassesVisitorArray, &local_arg); 1072 } 1073 for (int32_t i = 0; i < classes->GetLength(); ++i) { 1074 // If the class table shrank during creation of the clases array we expect null elements. If 1075 // the class table grew then the loop repeats. If classes are created after the loop has 1076 // finished then we don't visit. 1077 mirror::Class* klass = classes->Get(i); 1078 if (klass != nullptr && !visitor(klass, arg)) { 1079 return; 1080 } 1081 } 1082 } 1083} 1084 1085ClassLinker::~ClassLinker() { 1086 mirror::Class::ResetClass(); 1087 mirror::String::ResetClass(); 1088 mirror::Reference::ResetClass(); 1089 mirror::ArtField::ResetClass(); 1090 mirror::ArtMethod::ResetClass(); 1091 mirror::BooleanArray::ResetArrayClass(); 1092 mirror::ByteArray::ResetArrayClass(); 1093 mirror::CharArray::ResetArrayClass(); 1094 mirror::DoubleArray::ResetArrayClass(); 1095 mirror::FloatArray::ResetArrayClass(); 1096 mirror::IntArray::ResetArrayClass(); 1097 mirror::LongArray::ResetArrayClass(); 1098 mirror::ShortArray::ResetArrayClass(); 1099 mirror::Throwable::ResetClass(); 1100 mirror::StackTraceElement::ResetClass(); 1101 STLDeleteElements(&oat_files_); 1102} 1103 1104mirror::DexCache* ClassLinker::AllocDexCache(Thread* self, const DexFile& dex_file) { 1105 gc::Heap* heap = Runtime::Current()->GetHeap(); 1106 StackHandleScope<16> hs(self); 1107 Handle<mirror::Class> dex_cache_class(hs.NewHandle(GetClassRoot(kJavaLangDexCache))); 1108 Handle<mirror::DexCache> dex_cache( 1109 hs.NewHandle(down_cast<mirror::DexCache*>( 1110 heap->AllocObject<true>(self, dex_cache_class.Get(), dex_cache_class->GetObjectSize(), 1111 VoidFunctor())))); 1112 if (dex_cache.Get() == nullptr) { 1113 return nullptr; 1114 } 1115 Handle<mirror::String> 1116 location(hs.NewHandle(intern_table_->InternStrong(dex_file.GetLocation().c_str()))); 1117 if (location.Get() == nullptr) { 1118 return nullptr; 1119 } 1120 Handle<mirror::ObjectArray<mirror::String>> 1121 strings(hs.NewHandle(AllocStringArray(self, dex_file.NumStringIds()))); 1122 if (strings.Get() == nullptr) { 1123 return nullptr; 1124 } 1125 Handle<mirror::ObjectArray<mirror::Class>> 1126 types(hs.NewHandle(AllocClassArray(self, dex_file.NumTypeIds()))); 1127 if (types.Get() == nullptr) { 1128 return nullptr; 1129 } 1130 Handle<mirror::ObjectArray<mirror::ArtMethod>> 1131 methods(hs.NewHandle(AllocArtMethodArray(self, dex_file.NumMethodIds()))); 1132 if (methods.Get() == nullptr) { 1133 return nullptr; 1134 } 1135 Handle<mirror::ObjectArray<mirror::ArtField>> 1136 fields(hs.NewHandle(AllocArtFieldArray(self, dex_file.NumFieldIds()))); 1137 if (fields.Get() == nullptr) { 1138 return nullptr; 1139 } 1140 dex_cache->Init(&dex_file, location.Get(), strings.Get(), types.Get(), methods.Get(), 1141 fields.Get()); 1142 return dex_cache.Get(); 1143} 1144 1145mirror::Class* ClassLinker::AllocClass(Thread* self, mirror::Class* java_lang_Class, 1146 uint32_t class_size) { 1147 DCHECK_GE(class_size, sizeof(mirror::Class)); 1148 gc::Heap* heap = Runtime::Current()->GetHeap(); 1149 mirror::Class::InitializeClassVisitor visitor(class_size); 1150 mirror::Object* k = kMovingClasses ? 1151 heap->AllocObject<true>(self, java_lang_Class, class_size, visitor) : 1152 heap->AllocNonMovableObject<true>(self, java_lang_Class, class_size, visitor); 1153 if (UNLIKELY(k == nullptr)) { 1154 CHECK(self->IsExceptionPending()); // OOME. 1155 return nullptr; 1156 } 1157 return k->AsClass(); 1158} 1159 1160mirror::Class* ClassLinker::AllocClass(Thread* self, uint32_t class_size) { 1161 return AllocClass(self, GetClassRoot(kJavaLangClass), class_size); 1162} 1163 1164mirror::ArtField* ClassLinker::AllocArtField(Thread* self) { 1165 return down_cast<mirror::ArtField*>( 1166 GetClassRoot(kJavaLangReflectArtField)->AllocNonMovableObject(self)); 1167} 1168 1169mirror::ArtMethod* ClassLinker::AllocArtMethod(Thread* self) { 1170 return down_cast<mirror::ArtMethod*>( 1171 GetClassRoot(kJavaLangReflectArtMethod)->AllocNonMovableObject(self)); 1172} 1173 1174mirror::ObjectArray<mirror::StackTraceElement>* ClassLinker::AllocStackTraceElementArray( 1175 Thread* self, size_t length) { 1176 return mirror::ObjectArray<mirror::StackTraceElement>::Alloc( 1177 self, GetClassRoot(kJavaLangStackTraceElementArrayClass), length); 1178} 1179 1180mirror::Class* ClassLinker::EnsureResolved(Thread* self, const char* descriptor, 1181 mirror::Class* klass) { 1182 DCHECK(klass != nullptr); 1183 1184 // For temporary classes we must wait for them to be retired. 1185 if (init_done_ && klass->IsTemp()) { 1186 CHECK(!klass->IsResolved()); 1187 if (klass->IsErroneous()) { 1188 ThrowEarlierClassFailure(klass); 1189 return nullptr; 1190 } 1191 StackHandleScope<1> hs(self); 1192 Handle<mirror::Class> h_class(hs.NewHandle(klass)); 1193 ObjectLock<mirror::Class> lock(self, h_class); 1194 // Loop and wait for the resolving thread to retire this class. 1195 while (!h_class->IsRetired() && !h_class->IsErroneous()) { 1196 lock.WaitIgnoringInterrupts(); 1197 } 1198 if (h_class->IsErroneous()) { 1199 ThrowEarlierClassFailure(h_class.Get()); 1200 return nullptr; 1201 } 1202 CHECK(h_class->IsRetired()); 1203 // Get the updated class from class table. 1204 klass = LookupClass(self, descriptor, ComputeModifiedUtf8Hash(descriptor), 1205 h_class.Get()->GetClassLoader()); 1206 } 1207 1208 // Wait for the class if it has not already been linked. 1209 if (!klass->IsResolved() && !klass->IsErroneous()) { 1210 StackHandleScope<1> hs(self); 1211 HandleWrapper<mirror::Class> h_class(hs.NewHandleWrapper(&klass)); 1212 ObjectLock<mirror::Class> lock(self, h_class); 1213 // Check for circular dependencies between classes. 1214 if (!h_class->IsResolved() && h_class->GetClinitThreadId() == self->GetTid()) { 1215 ThrowClassCircularityError(h_class.Get()); 1216 mirror::Class::SetStatus(h_class, mirror::Class::kStatusError, self); 1217 return nullptr; 1218 } 1219 // Wait for the pending initialization to complete. 1220 while (!h_class->IsResolved() && !h_class->IsErroneous()) { 1221 lock.WaitIgnoringInterrupts(); 1222 } 1223 } 1224 1225 if (klass->IsErroneous()) { 1226 ThrowEarlierClassFailure(klass); 1227 return nullptr; 1228 } 1229 // Return the loaded class. No exceptions should be pending. 1230 CHECK(klass->IsResolved()) << PrettyClass(klass); 1231 self->AssertNoPendingException(); 1232 return klass; 1233} 1234 1235typedef std::pair<const DexFile*, const DexFile::ClassDef*> ClassPathEntry; 1236 1237// Search a collection of DexFiles for a descriptor 1238ClassPathEntry FindInClassPath(const char* descriptor, 1239 size_t hash, const std::vector<const DexFile*>& class_path) { 1240 for (const DexFile* dex_file : class_path) { 1241 const DexFile::ClassDef* dex_class_def = dex_file->FindClassDef(descriptor, hash); 1242 if (dex_class_def != nullptr) { 1243 return ClassPathEntry(dex_file, dex_class_def); 1244 } 1245 } 1246 return ClassPathEntry(nullptr, nullptr); 1247} 1248 1249mirror::Class* ClassLinker::FindClassInPathClassLoader(ScopedObjectAccessAlreadyRunnable& soa, 1250 Thread* self, const char* descriptor, 1251 size_t hash, 1252 Handle<mirror::ClassLoader> class_loader) { 1253 // Can we special case for a well understood PathClassLoader with the BootClassLoader as parent? 1254 if (class_loader->GetClass() != 1255 soa.Decode<mirror::Class*>(WellKnownClasses::dalvik_system_PathClassLoader) || 1256 class_loader->GetParent()->GetClass() != 1257 soa.Decode<mirror::Class*>(WellKnownClasses::java_lang_BootClassLoader)) { 1258 return nullptr; 1259 } 1260 ClassPathEntry pair = FindInClassPath(descriptor, hash, boot_class_path_); 1261 // Check if this would be found in the parent boot class loader. 1262 if (pair.second != nullptr) { 1263 mirror::Class* klass = LookupClass(self, descriptor, hash, nullptr); 1264 if (klass != nullptr) { 1265 // May return null if resolution on another thread fails. 1266 klass = EnsureResolved(self, descriptor, klass); 1267 } else { 1268 // May OOME. 1269 klass = DefineClass(self, descriptor, hash, NullHandle<mirror::ClassLoader>(), *pair.first, 1270 *pair.second); 1271 } 1272 if (klass == nullptr) { 1273 CHECK(self->IsExceptionPending()) << descriptor; 1274 self->ClearException(); 1275 } 1276 return klass; 1277 } else { 1278 // Handle as if this is the child PathClassLoader. 1279 // Handles as RegisterDexFile may allocate dex caches (and cause thread suspension). 1280 StackHandleScope<3> hs(self); 1281 // The class loader is a PathClassLoader which inherits from BaseDexClassLoader. 1282 // We need to get the DexPathList and loop through it. 1283 Handle<mirror::ArtField> cookie_field = 1284 hs.NewHandle(soa.DecodeField(WellKnownClasses::dalvik_system_DexFile_cookie)); 1285 Handle<mirror::ArtField> dex_file_field = 1286 hs.NewHandle( 1287 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList__Element_dexFile)); 1288 mirror::Object* dex_path_list = 1289 soa.DecodeField(WellKnownClasses::dalvik_system_PathClassLoader_pathList)-> 1290 GetObject(class_loader.Get()); 1291 if (dex_path_list != nullptr && dex_file_field.Get() != nullptr && 1292 cookie_field.Get() != nullptr) { 1293 // DexPathList has an array dexElements of Elements[] which each contain a dex file. 1294 mirror::Object* dex_elements_obj = 1295 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList_dexElements)-> 1296 GetObject(dex_path_list); 1297 // Loop through each dalvik.system.DexPathList$Element's dalvik.system.DexFile and look 1298 // at the mCookie which is a DexFile vector. 1299 if (dex_elements_obj != nullptr) { 1300 Handle<mirror::ObjectArray<mirror::Object>> dex_elements = 1301 hs.NewHandle(dex_elements_obj->AsObjectArray<mirror::Object>()); 1302 for (int32_t i = 0; i < dex_elements->GetLength(); ++i) { 1303 mirror::Object* element = dex_elements->GetWithoutChecks(i); 1304 if (element == nullptr) { 1305 // Should never happen, fall back to java code to throw a NPE. 1306 break; 1307 } 1308 mirror::Object* dex_file = dex_file_field->GetObject(element); 1309 if (dex_file != nullptr) { 1310 mirror::LongArray* long_array = cookie_field->GetObject(dex_file)->AsLongArray(); 1311 if (long_array == nullptr) { 1312 // This should never happen so log a warning. 1313 LOG(WARNING) << "Null DexFile::mCookie for " << descriptor; 1314 break; 1315 } 1316 int32_t long_array_size = long_array->GetLength(); 1317 for (int32_t j = 0; j < long_array_size; ++j) { 1318 const DexFile* cp_dex_file = reinterpret_cast<const DexFile*>(static_cast<uintptr_t>( 1319 long_array->GetWithoutChecks(j))); 1320 const DexFile::ClassDef* dex_class_def = cp_dex_file->FindClassDef(descriptor, hash); 1321 if (dex_class_def != nullptr) { 1322 RegisterDexFile(*cp_dex_file); 1323 mirror::Class* klass = DefineClass(self, descriptor, hash, class_loader, 1324 *cp_dex_file, *dex_class_def); 1325 if (klass == nullptr) { 1326 CHECK(self->IsExceptionPending()) << descriptor; 1327 self->ClearException(); 1328 return nullptr; 1329 } 1330 return klass; 1331 } 1332 } 1333 } 1334 } 1335 } 1336 } 1337 self->AssertNoPendingException(); 1338 return nullptr; 1339 } 1340} 1341 1342mirror::Class* ClassLinker::FindClass(Thread* self, const char* descriptor, 1343 Handle<mirror::ClassLoader> class_loader) { 1344 DCHECK_NE(*descriptor, '\0') << "descriptor is empty string"; 1345 DCHECK(self != nullptr); 1346 self->AssertNoPendingException(); 1347 if (descriptor[1] == '\0') { 1348 // only the descriptors of primitive types should be 1 character long, also avoid class lookup 1349 // for primitive classes that aren't backed by dex files. 1350 return FindPrimitiveClass(descriptor[0]); 1351 } 1352 const size_t hash = ComputeModifiedUtf8Hash(descriptor); 1353 // Find the class in the loaded classes table. 1354 mirror::Class* klass = LookupClass(self, descriptor, hash, class_loader.Get()); 1355 if (klass != nullptr) { 1356 return EnsureResolved(self, descriptor, klass); 1357 } 1358 // Class is not yet loaded. 1359 if (descriptor[0] == '[') { 1360 return CreateArrayClass(self, descriptor, hash, class_loader); 1361 } else if (class_loader.Get() == nullptr) { 1362 // The boot class loader, search the boot class path. 1363 ClassPathEntry pair = FindInClassPath(descriptor, hash, boot_class_path_); 1364 if (pair.second != nullptr) { 1365 return DefineClass(self, descriptor, hash, NullHandle<mirror::ClassLoader>(), *pair.first, 1366 *pair.second); 1367 } else { 1368 // The boot class loader is searched ahead of the application class loader, failures are 1369 // expected and will be wrapped in a ClassNotFoundException. Use the pre-allocated error to 1370 // trigger the chaining with a proper stack trace. 1371 mirror::Throwable* pre_allocated = Runtime::Current()->GetPreAllocatedNoClassDefFoundError(); 1372 self->SetException(pre_allocated); 1373 return nullptr; 1374 } 1375 } else { 1376 ScopedObjectAccessUnchecked soa(self); 1377 mirror::Class* cp_klass = FindClassInPathClassLoader(soa, self, descriptor, hash, 1378 class_loader); 1379 if (cp_klass != nullptr) { 1380 return cp_klass; 1381 } 1382 1383 if (Runtime::Current()->IsAotCompiler()) { 1384 // Oops, compile-time, can't run actual class-loader code. 1385 mirror::Throwable* pre_allocated = Runtime::Current()->GetPreAllocatedNoClassDefFoundError(); 1386 self->SetException(pre_allocated); 1387 return nullptr; 1388 } 1389 1390 ScopedLocalRef<jobject> class_loader_object(soa.Env(), 1391 soa.AddLocalReference<jobject>(class_loader.Get())); 1392 std::string class_name_string(DescriptorToDot(descriptor)); 1393 ScopedLocalRef<jobject> result(soa.Env(), nullptr); 1394 { 1395 ScopedThreadStateChange tsc(self, kNative); 1396 ScopedLocalRef<jobject> class_name_object(soa.Env(), 1397 soa.Env()->NewStringUTF(class_name_string.c_str())); 1398 if (class_name_object.get() == nullptr) { 1399 DCHECK(self->IsExceptionPending()); // OOME. 1400 return nullptr; 1401 } 1402 CHECK(class_loader_object.get() != nullptr); 1403 result.reset(soa.Env()->CallObjectMethod(class_loader_object.get(), 1404 WellKnownClasses::java_lang_ClassLoader_loadClass, 1405 class_name_object.get())); 1406 } 1407 if (self->IsExceptionPending()) { 1408 // If the ClassLoader threw, pass that exception up. 1409 return nullptr; 1410 } else if (result.get() == nullptr) { 1411 // broken loader - throw NPE to be compatible with Dalvik 1412 ThrowNullPointerException(StringPrintf("ClassLoader.loadClass returned null for %s", 1413 class_name_string.c_str()).c_str()); 1414 return nullptr; 1415 } else { 1416 // success, return mirror::Class* 1417 return soa.Decode<mirror::Class*>(result.get()); 1418 } 1419 } 1420 UNREACHABLE(); 1421} 1422 1423mirror::Class* ClassLinker::DefineClass(Thread* self, const char* descriptor, size_t hash, 1424 Handle<mirror::ClassLoader> class_loader, 1425 const DexFile& dex_file, 1426 const DexFile::ClassDef& dex_class_def) { 1427 StackHandleScope<3> hs(self); 1428 auto klass = hs.NewHandle<mirror::Class>(nullptr); 1429 1430 // Load the class from the dex file. 1431 if (UNLIKELY(!init_done_)) { 1432 // finish up init of hand crafted class_roots_ 1433 if (strcmp(descriptor, "Ljava/lang/Object;") == 0) { 1434 klass.Assign(GetClassRoot(kJavaLangObject)); 1435 } else if (strcmp(descriptor, "Ljava/lang/Class;") == 0) { 1436 klass.Assign(GetClassRoot(kJavaLangClass)); 1437 } else if (strcmp(descriptor, "Ljava/lang/String;") == 0) { 1438 klass.Assign(GetClassRoot(kJavaLangString)); 1439 } else if (strcmp(descriptor, "Ljava/lang/ref/Reference;") == 0) { 1440 klass.Assign(GetClassRoot(kJavaLangRefReference)); 1441 } else if (strcmp(descriptor, "Ljava/lang/DexCache;") == 0) { 1442 klass.Assign(GetClassRoot(kJavaLangDexCache)); 1443 } else if (strcmp(descriptor, "Ljava/lang/reflect/ArtField;") == 0) { 1444 klass.Assign(GetClassRoot(kJavaLangReflectArtField)); 1445 } else if (strcmp(descriptor, "Ljava/lang/reflect/ArtMethod;") == 0) { 1446 klass.Assign(GetClassRoot(kJavaLangReflectArtMethod)); 1447 } 1448 } 1449 1450 if (klass.Get() == nullptr) { 1451 // Allocate a class with the status of not ready. 1452 // Interface object should get the right size here. Regular class will 1453 // figure out the right size later and be replaced with one of the right 1454 // size when the class becomes resolved. 1455 klass.Assign(AllocClass(self, SizeOfClassWithoutEmbeddedTables(dex_file, dex_class_def))); 1456 } 1457 if (UNLIKELY(klass.Get() == nullptr)) { 1458 CHECK(self->IsExceptionPending()); // Expect an OOME. 1459 return nullptr; 1460 } 1461 klass->SetDexCache(FindDexCache(dex_file)); 1462 LoadClass(self, dex_file, dex_class_def, klass, class_loader.Get()); 1463 ObjectLock<mirror::Class> lock(self, klass); 1464 if (self->IsExceptionPending()) { 1465 // An exception occured during load, set status to erroneous while holding klass' lock in case 1466 // notification is necessary. 1467 if (!klass->IsErroneous()) { 1468 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 1469 } 1470 return nullptr; 1471 } 1472 klass->SetClinitThreadId(self->GetTid()); 1473 1474 // Add the newly loaded class to the loaded classes table. 1475 mirror::Class* existing = InsertClass(descriptor, klass.Get(), hash); 1476 if (existing != nullptr) { 1477 // We failed to insert because we raced with another thread. Calling EnsureResolved may cause 1478 // this thread to block. 1479 return EnsureResolved(self, descriptor, existing); 1480 } 1481 1482 // Finish loading (if necessary) by finding parents 1483 CHECK(!klass->IsLoaded()); 1484 if (!LoadSuperAndInterfaces(klass, dex_file)) { 1485 // Loading failed. 1486 if (!klass->IsErroneous()) { 1487 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 1488 } 1489 return nullptr; 1490 } 1491 CHECK(klass->IsLoaded()); 1492 // Link the class (if necessary) 1493 CHECK(!klass->IsResolved()); 1494 // TODO: Use fast jobjects? 1495 auto interfaces = hs.NewHandle<mirror::ObjectArray<mirror::Class>>(nullptr); 1496 1497 mirror::Class* new_class = nullptr; 1498 if (!LinkClass(self, descriptor, klass, interfaces, &new_class)) { 1499 // Linking failed. 1500 if (!klass->IsErroneous()) { 1501 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 1502 } 1503 return nullptr; 1504 } 1505 self->AssertNoPendingException(); 1506 CHECK(new_class != nullptr) << descriptor; 1507 CHECK(new_class->IsResolved()) << descriptor; 1508 1509 Handle<mirror::Class> new_class_h(hs.NewHandle(new_class)); 1510 1511 // Instrumentation may have updated entrypoints for all methods of all 1512 // classes. However it could not update methods of this class while we 1513 // were loading it. Now the class is resolved, we can update entrypoints 1514 // as required by instrumentation. 1515 if (Runtime::Current()->GetInstrumentation()->AreExitStubsInstalled()) { 1516 // We must be in the kRunnable state to prevent instrumentation from 1517 // suspending all threads to update entrypoints while we are doing it 1518 // for this class. 1519 DCHECK_EQ(self->GetState(), kRunnable); 1520 Runtime::Current()->GetInstrumentation()->InstallStubsForClass(new_class_h.Get()); 1521 } 1522 1523 /* 1524 * We send CLASS_PREPARE events to the debugger from here. The 1525 * definition of "preparation" is creating the static fields for a 1526 * class and initializing them to the standard default values, but not 1527 * executing any code (that comes later, during "initialization"). 1528 * 1529 * We did the static preparation in LinkClass. 1530 * 1531 * The class has been prepared and resolved but possibly not yet verified 1532 * at this point. 1533 */ 1534 Dbg::PostClassPrepare(new_class_h.Get()); 1535 1536 return new_class_h.Get(); 1537} 1538 1539uint32_t ClassLinker::SizeOfClassWithoutEmbeddedTables(const DexFile& dex_file, 1540 const DexFile::ClassDef& dex_class_def) { 1541 const uint8_t* class_data = dex_file.GetClassData(dex_class_def); 1542 size_t num_ref = 0; 1543 size_t num_8 = 0; 1544 size_t num_16 = 0; 1545 size_t num_32 = 0; 1546 size_t num_64 = 0; 1547 if (class_data != nullptr) { 1548 for (ClassDataItemIterator it(dex_file, class_data); it.HasNextStaticField(); it.Next()) { 1549 const DexFile::FieldId& field_id = dex_file.GetFieldId(it.GetMemberIndex()); 1550 const char* descriptor = dex_file.GetFieldTypeDescriptor(field_id); 1551 char c = descriptor[0]; 1552 switch (c) { 1553 case 'L': 1554 case '[': 1555 num_ref++; 1556 break; 1557 case 'J': 1558 case 'D': 1559 num_64++; 1560 break; 1561 case 'I': 1562 case 'F': 1563 num_32++; 1564 break; 1565 case 'S': 1566 case 'C': 1567 num_16++; 1568 break; 1569 case 'B': 1570 case 'Z': 1571 num_8++; 1572 break; 1573 default: 1574 LOG(FATAL) << "Unknown descriptor: " << c; 1575 UNREACHABLE(); 1576 } 1577 } 1578 } 1579 return mirror::Class::ComputeClassSize(false, 0, num_8, num_16, num_32, num_64, num_ref); 1580} 1581 1582OatFile::OatClass ClassLinker::FindOatClass(const DexFile& dex_file, uint16_t class_def_idx, 1583 bool* found) { 1584 DCHECK_NE(class_def_idx, DexFile::kDexNoIndex16); 1585 const OatFile::OatDexFile* oat_dex_file = FindOpenedOatDexFileForDexFile(dex_file); 1586 if (oat_dex_file == nullptr) { 1587 *found = false; 1588 return OatFile::OatClass::Invalid(); 1589 } 1590 *found = true; 1591 return oat_dex_file->GetOatClass(class_def_idx); 1592} 1593 1594static uint32_t GetOatMethodIndexFromMethodIndex(const DexFile& dex_file, uint16_t class_def_idx, 1595 uint32_t method_idx) { 1596 const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_idx); 1597 const uint8_t* class_data = dex_file.GetClassData(class_def); 1598 CHECK(class_data != nullptr); 1599 ClassDataItemIterator it(dex_file, class_data); 1600 // Skip fields 1601 while (it.HasNextStaticField()) { 1602 it.Next(); 1603 } 1604 while (it.HasNextInstanceField()) { 1605 it.Next(); 1606 } 1607 // Process methods 1608 size_t class_def_method_index = 0; 1609 while (it.HasNextDirectMethod()) { 1610 if (it.GetMemberIndex() == method_idx) { 1611 return class_def_method_index; 1612 } 1613 class_def_method_index++; 1614 it.Next(); 1615 } 1616 while (it.HasNextVirtualMethod()) { 1617 if (it.GetMemberIndex() == method_idx) { 1618 return class_def_method_index; 1619 } 1620 class_def_method_index++; 1621 it.Next(); 1622 } 1623 DCHECK(!it.HasNext()); 1624 LOG(FATAL) << "Failed to find method index " << method_idx << " in " << dex_file.GetLocation(); 1625 UNREACHABLE(); 1626} 1627 1628const OatFile::OatMethod ClassLinker::FindOatMethodFor(mirror::ArtMethod* method, bool* found) { 1629 // Although we overwrite the trampoline of non-static methods, we may get here via the resolution 1630 // method for direct methods (or virtual methods made direct). 1631 mirror::Class* declaring_class = method->GetDeclaringClass(); 1632 size_t oat_method_index; 1633 if (method->IsStatic() || method->IsDirect()) { 1634 // Simple case where the oat method index was stashed at load time. 1635 oat_method_index = method->GetMethodIndex(); 1636 } else { 1637 // We're invoking a virtual method directly (thanks to sharpening), compute the oat_method_index 1638 // by search for its position in the declared virtual methods. 1639 oat_method_index = declaring_class->NumDirectMethods(); 1640 size_t end = declaring_class->NumVirtualMethods(); 1641 bool found_virtual = false; 1642 for (size_t i = 0; i < end; i++) { 1643 // Check method index instead of identity in case of duplicate method definitions. 1644 if (method->GetDexMethodIndex() == 1645 declaring_class->GetVirtualMethod(i)->GetDexMethodIndex()) { 1646 found_virtual = true; 1647 break; 1648 } 1649 oat_method_index++; 1650 } 1651 CHECK(found_virtual) << "Didn't find oat method index for virtual method: " 1652 << PrettyMethod(method); 1653 } 1654 DCHECK_EQ(oat_method_index, 1655 GetOatMethodIndexFromMethodIndex(*declaring_class->GetDexCache()->GetDexFile(), 1656 method->GetDeclaringClass()->GetDexClassDefIndex(), 1657 method->GetDexMethodIndex())); 1658 OatFile::OatClass oat_class = FindOatClass(*declaring_class->GetDexCache()->GetDexFile(), 1659 declaring_class->GetDexClassDefIndex(), 1660 found); 1661 if (!(*found)) { 1662 return OatFile::OatMethod::Invalid(); 1663 } 1664 return oat_class.GetOatMethod(oat_method_index); 1665} 1666 1667// Special case to get oat code without overwriting a trampoline. 1668const void* ClassLinker::GetQuickOatCodeFor(mirror::ArtMethod* method) { 1669 CHECK(!method->IsAbstract()) << PrettyMethod(method); 1670 if (method->IsProxyMethod()) { 1671 return GetQuickProxyInvokeHandler(); 1672 } 1673 bool found; 1674 OatFile::OatMethod oat_method = FindOatMethodFor(method, &found); 1675 if (found) { 1676 auto* code = oat_method.GetQuickCode(); 1677 if (code != nullptr) { 1678 return code; 1679 } 1680 } 1681 jit::Jit* const jit = Runtime::Current()->GetJit(); 1682 if (jit != nullptr) { 1683 auto* code = jit->GetCodeCache()->GetCodeFor(method); 1684 if (code != nullptr) { 1685 return code; 1686 } 1687 } 1688 if (method->IsNative()) { 1689 // No code and native? Use generic trampoline. 1690 return GetQuickGenericJniStub(); 1691 } 1692 return GetQuickToInterpreterBridge(); 1693} 1694 1695const void* ClassLinker::GetOatMethodQuickCodeFor(mirror::ArtMethod* method) { 1696 if (method->IsNative() || method->IsAbstract() || method->IsProxyMethod()) { 1697 return nullptr; 1698 } 1699 bool found; 1700 OatFile::OatMethod oat_method = FindOatMethodFor(method, &found); 1701 if (found) { 1702 return oat_method.GetQuickCode(); 1703 } 1704 jit::Jit* jit = Runtime::Current()->GetJit(); 1705 if (jit != nullptr) { 1706 auto* code = jit->GetCodeCache()->GetCodeFor(method); 1707 if (code != nullptr) { 1708 return code; 1709 } 1710 } 1711 return nullptr; 1712} 1713 1714const void* ClassLinker::GetQuickOatCodeFor(const DexFile& dex_file, uint16_t class_def_idx, 1715 uint32_t method_idx) { 1716 bool found; 1717 OatFile::OatClass oat_class = FindOatClass(dex_file, class_def_idx, &found); 1718 if (!found) { 1719 return nullptr; 1720 } 1721 uint32_t oat_method_idx = GetOatMethodIndexFromMethodIndex(dex_file, class_def_idx, method_idx); 1722 return oat_class.GetOatMethod(oat_method_idx).GetQuickCode(); 1723} 1724 1725// Returns true if the method must run with interpreter, false otherwise. 1726static bool NeedsInterpreter(mirror::ArtMethod* method, const void* quick_code) 1727 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1728 if (quick_code == nullptr) { 1729 // No code: need interpreter. 1730 // May return true for native code, in the case of generic JNI 1731 // DCHECK(!method->IsNative()); 1732 return true; 1733 } 1734 // If interpreter mode is enabled, every method (except native and proxy) must 1735 // be run with interpreter. 1736 return Runtime::Current()->GetInstrumentation()->InterpretOnly() && 1737 !method->IsNative() && !method->IsProxyMethod(); 1738} 1739 1740void ClassLinker::FixupStaticTrampolines(mirror::Class* klass) { 1741 DCHECK(klass->IsInitialized()) << PrettyDescriptor(klass); 1742 if (klass->NumDirectMethods() == 0) { 1743 return; // No direct methods => no static methods. 1744 } 1745 Runtime* runtime = Runtime::Current(); 1746 if (!runtime->IsStarted()) { 1747 if (runtime->IsAotCompiler() || runtime->GetHeap()->HasImageSpace()) { 1748 return; // OAT file unavailable. 1749 } 1750 } 1751 1752 const DexFile& dex_file = klass->GetDexFile(); 1753 const DexFile::ClassDef* dex_class_def = klass->GetClassDef(); 1754 CHECK(dex_class_def != nullptr); 1755 const uint8_t* class_data = dex_file.GetClassData(*dex_class_def); 1756 // There should always be class data if there were direct methods. 1757 CHECK(class_data != nullptr) << PrettyDescriptor(klass); 1758 ClassDataItemIterator it(dex_file, class_data); 1759 // Skip fields 1760 while (it.HasNextStaticField()) { 1761 it.Next(); 1762 } 1763 while (it.HasNextInstanceField()) { 1764 it.Next(); 1765 } 1766 bool has_oat_class; 1767 OatFile::OatClass oat_class = FindOatClass(dex_file, klass->GetDexClassDefIndex(), 1768 &has_oat_class); 1769 // Link the code of methods skipped by LinkCode. 1770 for (size_t method_index = 0; it.HasNextDirectMethod(); ++method_index, it.Next()) { 1771 mirror::ArtMethod* method = klass->GetDirectMethod(method_index); 1772 if (!method->IsStatic()) { 1773 // Only update static methods. 1774 continue; 1775 } 1776 const void* quick_code = nullptr; 1777 if (has_oat_class) { 1778 OatFile::OatMethod oat_method = oat_class.GetOatMethod(method_index); 1779 quick_code = oat_method.GetQuickCode(); 1780 } 1781 const bool enter_interpreter = NeedsInterpreter(method, quick_code); 1782 if (enter_interpreter) { 1783 // Use interpreter entry point. 1784 // Check whether the method is native, in which case it's generic JNI. 1785 if (quick_code == nullptr && method->IsNative()) { 1786 quick_code = GetQuickGenericJniStub(); 1787 } else { 1788 quick_code = GetQuickToInterpreterBridge(); 1789 } 1790 } 1791 runtime->GetInstrumentation()->UpdateMethodsCode(method, quick_code); 1792 } 1793 // Ignore virtual methods on the iterator. 1794} 1795 1796void ClassLinker::LinkCode(Handle<mirror::ArtMethod> method, 1797 const OatFile::OatClass* oat_class, 1798 uint32_t class_def_method_index) { 1799 Runtime* runtime = Runtime::Current(); 1800 if (runtime->IsAotCompiler()) { 1801 // The following code only applies to a non-compiler runtime. 1802 return; 1803 } 1804 // Method shouldn't have already been linked. 1805 DCHECK(method->GetEntryPointFromQuickCompiledCode() == nullptr); 1806 if (oat_class != nullptr) { 1807 // Every kind of method should at least get an invoke stub from the oat_method. 1808 // non-abstract methods also get their code pointers. 1809 const OatFile::OatMethod oat_method = oat_class->GetOatMethod(class_def_method_index); 1810 oat_method.LinkMethod(method.Get()); 1811 } 1812 1813 // Install entry point from interpreter. 1814 bool enter_interpreter = NeedsInterpreter(method.Get(), 1815 method->GetEntryPointFromQuickCompiledCode()); 1816 if (enter_interpreter && !method->IsNative()) { 1817 method->SetEntryPointFromInterpreter(artInterpreterToInterpreterBridge); 1818 } else { 1819 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 1820 } 1821 1822 if (method->IsAbstract()) { 1823 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge()); 1824 return; 1825 } 1826 1827 if (method->IsStatic() && !method->IsConstructor()) { 1828 // For static methods excluding the class initializer, install the trampoline. 1829 // It will be replaced by the proper entry point by ClassLinker::FixupStaticTrampolines 1830 // after initializing class (see ClassLinker::InitializeClass method). 1831 method->SetEntryPointFromQuickCompiledCode(GetQuickResolutionStub()); 1832 } else if (enter_interpreter) { 1833 if (!method->IsNative()) { 1834 // Set entry point from compiled code if there's no code or in interpreter only mode. 1835 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge()); 1836 } else { 1837 method->SetEntryPointFromQuickCompiledCode(GetQuickGenericJniStub()); 1838 } 1839 } 1840 1841 if (method->IsNative()) { 1842 // Unregistering restores the dlsym lookup stub. 1843 method->UnregisterNative(); 1844 1845 if (enter_interpreter) { 1846 // We have a native method here without code. Then it should have either the generic JNI 1847 // trampoline as entrypoint (non-static), or the resolution trampoline (static). 1848 // TODO: this doesn't handle all the cases where trampolines may be installed. 1849 const void* entry_point = method->GetEntryPointFromQuickCompiledCode(); 1850 DCHECK(IsQuickGenericJniStub(entry_point) || IsQuickResolutionStub(entry_point)); 1851 } 1852 } 1853} 1854 1855 1856 1857void ClassLinker::LoadClass(Thread* self, const DexFile& dex_file, 1858 const DexFile::ClassDef& dex_class_def, 1859 Handle<mirror::Class> klass, 1860 mirror::ClassLoader* class_loader) { 1861 CHECK(klass.Get() != nullptr); 1862 CHECK(klass->GetDexCache() != nullptr); 1863 CHECK_EQ(mirror::Class::kStatusNotReady, klass->GetStatus()); 1864 const char* descriptor = dex_file.GetClassDescriptor(dex_class_def); 1865 CHECK(descriptor != nullptr); 1866 1867 klass->SetClass(GetClassRoot(kJavaLangClass)); 1868 uint32_t access_flags = dex_class_def.GetJavaAccessFlags(); 1869 CHECK_EQ(access_flags & ~kAccJavaFlagsMask, 0U); 1870 klass->SetAccessFlags(access_flags); 1871 klass->SetClassLoader(class_loader); 1872 DCHECK_EQ(klass->GetPrimitiveType(), Primitive::kPrimNot); 1873 mirror::Class::SetStatus(klass, mirror::Class::kStatusIdx, nullptr); 1874 1875 klass->SetDexClassDefIndex(dex_file.GetIndexForClassDef(dex_class_def)); 1876 klass->SetDexTypeIndex(dex_class_def.class_idx_); 1877 CHECK(klass->GetDexCacheStrings() != nullptr); 1878 1879 const uint8_t* class_data = dex_file.GetClassData(dex_class_def); 1880 if (class_data == nullptr) { 1881 return; // no fields or methods - for example a marker interface 1882 } 1883 1884 1885 bool has_oat_class = false; 1886 if (Runtime::Current()->IsStarted() && !Runtime::Current()->IsAotCompiler()) { 1887 OatFile::OatClass oat_class = FindOatClass(dex_file, klass->GetDexClassDefIndex(), 1888 &has_oat_class); 1889 if (has_oat_class) { 1890 LoadClassMembers(self, dex_file, class_data, klass, &oat_class); 1891 } 1892 } 1893 if (!has_oat_class) { 1894 LoadClassMembers(self, dex_file, class_data, klass, nullptr); 1895 } 1896} 1897 1898void ClassLinker::LoadClassMembers(Thread* self, const DexFile& dex_file, 1899 const uint8_t* class_data, 1900 Handle<mirror::Class> klass, 1901 const OatFile::OatClass* oat_class) { 1902 // Load fields. 1903 ClassDataItemIterator it(dex_file, class_data); 1904 if (it.NumStaticFields() != 0) { 1905 mirror::ObjectArray<mirror::ArtField>* statics = AllocArtFieldArray(self, it.NumStaticFields()); 1906 if (UNLIKELY(statics == nullptr)) { 1907 CHECK(self->IsExceptionPending()); // OOME. 1908 return; 1909 } 1910 klass->SetSFields(statics); 1911 } 1912 if (it.NumInstanceFields() != 0) { 1913 mirror::ObjectArray<mirror::ArtField>* fields = 1914 AllocArtFieldArray(self, it.NumInstanceFields()); 1915 if (UNLIKELY(fields == nullptr)) { 1916 CHECK(self->IsExceptionPending()); // OOME. 1917 return; 1918 } 1919 klass->SetIFields(fields); 1920 } 1921 for (size_t i = 0; it.HasNextStaticField(); i++, it.Next()) { 1922 self->AllowThreadSuspension(); 1923 StackHandleScope<1> hs(self); 1924 Handle<mirror::ArtField> sfield(hs.NewHandle(AllocArtField(self))); 1925 if (UNLIKELY(sfield.Get() == nullptr)) { 1926 CHECK(self->IsExceptionPending()); // OOME. 1927 return; 1928 } 1929 klass->SetStaticField(i, sfield.Get()); 1930 LoadField(dex_file, it, klass, sfield); 1931 } 1932 for (size_t i = 0; it.HasNextInstanceField(); i++, it.Next()) { 1933 self->AllowThreadSuspension(); 1934 StackHandleScope<1> hs(self); 1935 Handle<mirror::ArtField> ifield(hs.NewHandle(AllocArtField(self))); 1936 if (UNLIKELY(ifield.Get() == nullptr)) { 1937 CHECK(self->IsExceptionPending()); // OOME. 1938 return; 1939 } 1940 klass->SetInstanceField(i, ifield.Get()); 1941 LoadField(dex_file, it, klass, ifield); 1942 } 1943 1944 // Load methods. 1945 if (it.NumDirectMethods() != 0) { 1946 // TODO: append direct methods to class object 1947 mirror::ObjectArray<mirror::ArtMethod>* directs = 1948 AllocArtMethodArray(self, it.NumDirectMethods()); 1949 if (UNLIKELY(directs == nullptr)) { 1950 CHECK(self->IsExceptionPending()); // OOME. 1951 return; 1952 } 1953 klass->SetDirectMethods(directs); 1954 } 1955 if (it.NumVirtualMethods() != 0) { 1956 // TODO: append direct methods to class object 1957 mirror::ObjectArray<mirror::ArtMethod>* virtuals = 1958 AllocArtMethodArray(self, it.NumVirtualMethods()); 1959 if (UNLIKELY(virtuals == nullptr)) { 1960 CHECK(self->IsExceptionPending()); // OOME. 1961 return; 1962 } 1963 klass->SetVirtualMethods(virtuals); 1964 } 1965 size_t class_def_method_index = 0; 1966 uint32_t last_dex_method_index = DexFile::kDexNoIndex; 1967 size_t last_class_def_method_index = 0; 1968 for (size_t i = 0; it.HasNextDirectMethod(); i++, it.Next()) { 1969 self->AllowThreadSuspension(); 1970 StackHandleScope<1> hs(self); 1971 Handle<mirror::ArtMethod> method(hs.NewHandle(LoadMethod(self, dex_file, it, klass))); 1972 if (UNLIKELY(method.Get() == nullptr)) { 1973 CHECK(self->IsExceptionPending()); // OOME. 1974 return; 1975 } 1976 klass->SetDirectMethod(i, method.Get()); 1977 LinkCode(method, oat_class, class_def_method_index); 1978 uint32_t it_method_index = it.GetMemberIndex(); 1979 if (last_dex_method_index == it_method_index) { 1980 // duplicate case 1981 method->SetMethodIndex(last_class_def_method_index); 1982 } else { 1983 method->SetMethodIndex(class_def_method_index); 1984 last_dex_method_index = it_method_index; 1985 last_class_def_method_index = class_def_method_index; 1986 } 1987 class_def_method_index++; 1988 } 1989 for (size_t i = 0; it.HasNextVirtualMethod(); i++, it.Next()) { 1990 self->AllowThreadSuspension(); 1991 StackHandleScope<1> hs(self); 1992 Handle<mirror::ArtMethod> method(hs.NewHandle(LoadMethod(self, dex_file, it, klass))); 1993 if (UNLIKELY(method.Get() == nullptr)) { 1994 CHECK(self->IsExceptionPending()); // OOME. 1995 return; 1996 } 1997 klass->SetVirtualMethod(i, method.Get()); 1998 DCHECK_EQ(class_def_method_index, it.NumDirectMethods() + i); 1999 LinkCode(method, oat_class, class_def_method_index); 2000 class_def_method_index++; 2001 } 2002 DCHECK(!it.HasNext()); 2003} 2004 2005void ClassLinker::LoadField(const DexFile& /*dex_file*/, const ClassDataItemIterator& it, 2006 Handle<mirror::Class> klass, 2007 Handle<mirror::ArtField> dst) { 2008 uint32_t field_idx = it.GetMemberIndex(); 2009 dst->SetDexFieldIndex(field_idx); 2010 dst->SetDeclaringClass(klass.Get()); 2011 dst->SetAccessFlags(it.GetFieldAccessFlags()); 2012} 2013 2014mirror::ArtMethod* ClassLinker::LoadMethod(Thread* self, const DexFile& dex_file, 2015 const ClassDataItemIterator& it, 2016 Handle<mirror::Class> klass) { 2017 uint32_t dex_method_idx = it.GetMemberIndex(); 2018 const DexFile::MethodId& method_id = dex_file.GetMethodId(dex_method_idx); 2019 const char* method_name = dex_file.StringDataByIdx(method_id.name_idx_); 2020 2021 mirror::ArtMethod* dst = AllocArtMethod(self); 2022 if (UNLIKELY(dst == nullptr)) { 2023 CHECK(self->IsExceptionPending()); // OOME. 2024 return nullptr; 2025 } 2026 DCHECK(dst->IsArtMethod()) << PrettyDescriptor(dst->GetClass()); 2027 2028 ScopedAssertNoThreadSuspension ants(self, "LoadMethod"); 2029 dst->SetDexMethodIndex(dex_method_idx); 2030 dst->SetDeclaringClass(klass.Get()); 2031 dst->SetCodeItemOffset(it.GetMethodCodeItemOffset()); 2032 2033 dst->SetDexCacheResolvedMethods(klass->GetDexCache()->GetResolvedMethods()); 2034 dst->SetDexCacheResolvedTypes(klass->GetDexCache()->GetResolvedTypes()); 2035 2036 uint32_t access_flags = it.GetMethodAccessFlags(); 2037 2038 if (UNLIKELY(strcmp("finalize", method_name) == 0)) { 2039 // Set finalizable flag on declaring class. 2040 if (strcmp("V", dex_file.GetShorty(method_id.proto_idx_)) == 0) { 2041 // Void return type. 2042 if (klass->GetClassLoader() != nullptr) { // All non-boot finalizer methods are flagged. 2043 klass->SetFinalizable(); 2044 } else { 2045 std::string temp; 2046 const char* klass_descriptor = klass->GetDescriptor(&temp); 2047 // The Enum class declares a "final" finalize() method to prevent subclasses from 2048 // introducing a finalizer. We don't want to set the finalizable flag for Enum or its 2049 // subclasses, so we exclude it here. 2050 // We also want to avoid setting the flag on Object, where we know that finalize() is 2051 // empty. 2052 if (strcmp(klass_descriptor, "Ljava/lang/Object;") != 0 && 2053 strcmp(klass_descriptor, "Ljava/lang/Enum;") != 0) { 2054 klass->SetFinalizable(); 2055 } 2056 } 2057 } 2058 } else if (method_name[0] == '<') { 2059 // Fix broken access flags for initializers. Bug 11157540. 2060 bool is_init = (strcmp("<init>", method_name) == 0); 2061 bool is_clinit = !is_init && (strcmp("<clinit>", method_name) == 0); 2062 if (UNLIKELY(!is_init && !is_clinit)) { 2063 LOG(WARNING) << "Unexpected '<' at start of method name " << method_name; 2064 } else { 2065 if (UNLIKELY((access_flags & kAccConstructor) == 0)) { 2066 LOG(WARNING) << method_name << " didn't have expected constructor access flag in class " 2067 << PrettyDescriptor(klass.Get()) << " in dex file " << dex_file.GetLocation(); 2068 access_flags |= kAccConstructor; 2069 } 2070 } 2071 } 2072 dst->SetAccessFlags(access_flags); 2073 2074 return dst; 2075} 2076 2077void ClassLinker::AppendToBootClassPath(Thread* self, const DexFile& dex_file) { 2078 StackHandleScope<1> hs(self); 2079 Handle<mirror::DexCache> dex_cache(hs.NewHandle(AllocDexCache(self, dex_file))); 2080 CHECK(dex_cache.Get() != nullptr) << "Failed to allocate dex cache for " 2081 << dex_file.GetLocation(); 2082 AppendToBootClassPath(dex_file, dex_cache); 2083} 2084 2085void ClassLinker::AppendToBootClassPath(const DexFile& dex_file, 2086 Handle<mirror::DexCache> dex_cache) { 2087 CHECK(dex_cache.Get() != nullptr) << dex_file.GetLocation(); 2088 boot_class_path_.push_back(&dex_file); 2089 RegisterDexFile(dex_file, dex_cache); 2090} 2091 2092bool ClassLinker::IsDexFileRegisteredLocked(const DexFile& dex_file) { 2093 dex_lock_.AssertSharedHeld(Thread::Current()); 2094 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2095 mirror::DexCache* dex_cache = GetDexCache(i); 2096 if (dex_cache->GetDexFile() == &dex_file) { 2097 return true; 2098 } 2099 } 2100 return false; 2101} 2102 2103bool ClassLinker::IsDexFileRegistered(const DexFile& dex_file) { 2104 ReaderMutexLock mu(Thread::Current(), dex_lock_); 2105 return IsDexFileRegisteredLocked(dex_file); 2106} 2107 2108void ClassLinker::RegisterDexFileLocked(const DexFile& dex_file, 2109 Handle<mirror::DexCache> dex_cache) { 2110 dex_lock_.AssertExclusiveHeld(Thread::Current()); 2111 CHECK(dex_cache.Get() != nullptr) << dex_file.GetLocation(); 2112 CHECK(dex_cache->GetLocation()->Equals(dex_file.GetLocation())) 2113 << dex_cache->GetLocation()->ToModifiedUtf8() << " " << dex_file.GetLocation(); 2114 dex_caches_.push_back(GcRoot<mirror::DexCache>(dex_cache.Get())); 2115 dex_cache->SetDexFile(&dex_file); 2116 if (log_new_dex_caches_roots_) { 2117 // TODO: This is not safe if we can remove dex caches. 2118 new_dex_cache_roots_.push_back(dex_caches_.size() - 1); 2119 } 2120} 2121 2122void ClassLinker::RegisterDexFile(const DexFile& dex_file) { 2123 Thread* self = Thread::Current(); 2124 { 2125 ReaderMutexLock mu(self, dex_lock_); 2126 if (IsDexFileRegisteredLocked(dex_file)) { 2127 return; 2128 } 2129 } 2130 // Don't alloc while holding the lock, since allocation may need to 2131 // suspend all threads and another thread may need the dex_lock_ to 2132 // get to a suspend point. 2133 StackHandleScope<1> hs(self); 2134 Handle<mirror::DexCache> dex_cache(hs.NewHandle(AllocDexCache(self, dex_file))); 2135 CHECK(dex_cache.Get() != nullptr) << "Failed to allocate dex cache for " 2136 << dex_file.GetLocation(); 2137 { 2138 WriterMutexLock mu(self, dex_lock_); 2139 if (IsDexFileRegisteredLocked(dex_file)) { 2140 return; 2141 } 2142 RegisterDexFileLocked(dex_file, dex_cache); 2143 } 2144} 2145 2146void ClassLinker::RegisterDexFile(const DexFile& dex_file, 2147 Handle<mirror::DexCache> dex_cache) { 2148 WriterMutexLock mu(Thread::Current(), dex_lock_); 2149 RegisterDexFileLocked(dex_file, dex_cache); 2150} 2151 2152mirror::DexCache* ClassLinker::FindDexCache(const DexFile& dex_file) { 2153 ReaderMutexLock mu(Thread::Current(), dex_lock_); 2154 // Search assuming unique-ness of dex file. 2155 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2156 mirror::DexCache* dex_cache = GetDexCache(i); 2157 if (dex_cache->GetDexFile() == &dex_file) { 2158 return dex_cache; 2159 } 2160 } 2161 // Search matching by location name. 2162 std::string location(dex_file.GetLocation()); 2163 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2164 mirror::DexCache* dex_cache = GetDexCache(i); 2165 if (dex_cache->GetDexFile()->GetLocation() == location) { 2166 return dex_cache; 2167 } 2168 } 2169 // Failure, dump diagnostic and abort. 2170 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2171 mirror::DexCache* dex_cache = GetDexCache(i); 2172 LOG(ERROR) << "Registered dex file " << i << " = " << dex_cache->GetDexFile()->GetLocation(); 2173 } 2174 LOG(FATAL) << "Failed to find DexCache for DexFile " << location; 2175 UNREACHABLE(); 2176} 2177 2178void ClassLinker::FixupDexCaches(mirror::ArtMethod* resolution_method) { 2179 ReaderMutexLock mu(Thread::Current(), dex_lock_); 2180 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2181 mirror::DexCache* dex_cache = GetDexCache(i); 2182 dex_cache->Fixup(resolution_method); 2183 } 2184} 2185 2186mirror::Class* ClassLinker::CreatePrimitiveClass(Thread* self, Primitive::Type type) { 2187 mirror::Class* klass = AllocClass(self, mirror::Class::PrimitiveClassSize()); 2188 if (UNLIKELY(klass == nullptr)) { 2189 return nullptr; 2190 } 2191 return InitializePrimitiveClass(klass, type); 2192} 2193 2194mirror::Class* ClassLinker::InitializePrimitiveClass(mirror::Class* primitive_class, 2195 Primitive::Type type) { 2196 CHECK(primitive_class != nullptr); 2197 // Must hold lock on object when initializing. 2198 Thread* self = Thread::Current(); 2199 StackHandleScope<1> hs(self); 2200 Handle<mirror::Class> h_class(hs.NewHandle(primitive_class)); 2201 ObjectLock<mirror::Class> lock(self, h_class); 2202 h_class->SetAccessFlags(kAccPublic | kAccFinal | kAccAbstract); 2203 h_class->SetPrimitiveType(type); 2204 mirror::Class::SetStatus(h_class, mirror::Class::kStatusInitialized, self); 2205 const char* descriptor = Primitive::Descriptor(type); 2206 mirror::Class* existing = InsertClass(descriptor, h_class.Get(), 2207 ComputeModifiedUtf8Hash(descriptor)); 2208 CHECK(existing == nullptr) << "InitPrimitiveClass(" << type << ") failed"; 2209 return h_class.Get(); 2210} 2211 2212// Create an array class (i.e. the class object for the array, not the 2213// array itself). "descriptor" looks like "[C" or "[[[[B" or 2214// "[Ljava/lang/String;". 2215// 2216// If "descriptor" refers to an array of primitives, look up the 2217// primitive type's internally-generated class object. 2218// 2219// "class_loader" is the class loader of the class that's referring to 2220// us. It's used to ensure that we're looking for the element type in 2221// the right context. It does NOT become the class loader for the 2222// array class; that always comes from the base element class. 2223// 2224// Returns nullptr with an exception raised on failure. 2225mirror::Class* ClassLinker::CreateArrayClass(Thread* self, const char* descriptor, size_t hash, 2226 Handle<mirror::ClassLoader> class_loader) { 2227 // Identify the underlying component type 2228 CHECK_EQ('[', descriptor[0]); 2229 StackHandleScope<2> hs(self); 2230 MutableHandle<mirror::Class> component_type(hs.NewHandle(FindClass(self, descriptor + 1, 2231 class_loader))); 2232 if (component_type.Get() == nullptr) { 2233 DCHECK(self->IsExceptionPending()); 2234 // We need to accept erroneous classes as component types. 2235 const size_t component_hash = ComputeModifiedUtf8Hash(descriptor + 1); 2236 component_type.Assign(LookupClass(self, descriptor + 1, component_hash, class_loader.Get())); 2237 if (component_type.Get() == nullptr) { 2238 DCHECK(self->IsExceptionPending()); 2239 return nullptr; 2240 } else { 2241 self->ClearException(); 2242 } 2243 } 2244 if (UNLIKELY(component_type->IsPrimitiveVoid())) { 2245 ThrowNoClassDefFoundError("Attempt to create array of void primitive type"); 2246 return nullptr; 2247 } 2248 // See if the component type is already loaded. Array classes are 2249 // always associated with the class loader of their underlying 2250 // element type -- an array of Strings goes with the loader for 2251 // java/lang/String -- so we need to look for it there. (The 2252 // caller should have checked for the existence of the class 2253 // before calling here, but they did so with *their* class loader, 2254 // not the component type's loader.) 2255 // 2256 // If we find it, the caller adds "loader" to the class' initiating 2257 // loader list, which should prevent us from going through this again. 2258 // 2259 // This call is unnecessary if "loader" and "component_type->GetClassLoader()" 2260 // are the same, because our caller (FindClass) just did the 2261 // lookup. (Even if we get this wrong we still have correct behavior, 2262 // because we effectively do this lookup again when we add the new 2263 // class to the hash table --- necessary because of possible races with 2264 // other threads.) 2265 if (class_loader.Get() != component_type->GetClassLoader()) { 2266 mirror::Class* new_class = LookupClass(self, descriptor, hash, component_type->GetClassLoader()); 2267 if (new_class != nullptr) { 2268 return new_class; 2269 } 2270 } 2271 2272 // Fill out the fields in the Class. 2273 // 2274 // It is possible to execute some methods against arrays, because 2275 // all arrays are subclasses of java_lang_Object_, so we need to set 2276 // up a vtable. We can just point at the one in java_lang_Object_. 2277 // 2278 // Array classes are simple enough that we don't need to do a full 2279 // link step. 2280 auto new_class = hs.NewHandle<mirror::Class>(nullptr); 2281 if (UNLIKELY(!init_done_)) { 2282 // Classes that were hand created, ie not by FindSystemClass 2283 if (strcmp(descriptor, "[Ljava/lang/Class;") == 0) { 2284 new_class.Assign(GetClassRoot(kClassArrayClass)); 2285 } else if (strcmp(descriptor, "[Ljava/lang/Object;") == 0) { 2286 new_class.Assign(GetClassRoot(kObjectArrayClass)); 2287 } else if (strcmp(descriptor, GetClassRootDescriptor(kJavaLangStringArrayClass)) == 0) { 2288 new_class.Assign(GetClassRoot(kJavaLangStringArrayClass)); 2289 } else if (strcmp(descriptor, 2290 GetClassRootDescriptor(kJavaLangReflectArtMethodArrayClass)) == 0) { 2291 new_class.Assign(GetClassRoot(kJavaLangReflectArtMethodArrayClass)); 2292 } else if (strcmp(descriptor, 2293 GetClassRootDescriptor(kJavaLangReflectArtFieldArrayClass)) == 0) { 2294 new_class.Assign(GetClassRoot(kJavaLangReflectArtFieldArrayClass)); 2295 } else if (strcmp(descriptor, "[C") == 0) { 2296 new_class.Assign(GetClassRoot(kCharArrayClass)); 2297 } else if (strcmp(descriptor, "[I") == 0) { 2298 new_class.Assign(GetClassRoot(kIntArrayClass)); 2299 } 2300 } 2301 if (new_class.Get() == nullptr) { 2302 new_class.Assign(AllocClass(self, mirror::Array::ClassSize())); 2303 if (new_class.Get() == nullptr) { 2304 return nullptr; 2305 } 2306 new_class->SetComponentType(component_type.Get()); 2307 } 2308 ObjectLock<mirror::Class> lock(self, new_class); // Must hold lock on object when initializing. 2309 DCHECK(new_class->GetComponentType() != nullptr); 2310 mirror::Class* java_lang_Object = GetClassRoot(kJavaLangObject); 2311 new_class->SetSuperClass(java_lang_Object); 2312 new_class->SetVTable(java_lang_Object->GetVTable()); 2313 new_class->SetPrimitiveType(Primitive::kPrimNot); 2314 new_class->SetClassLoader(component_type->GetClassLoader()); 2315 mirror::Class::SetStatus(new_class, mirror::Class::kStatusLoaded, self); 2316 { 2317 StackHandleScope<mirror::Class::kImtSize> hs2(self, 2318 Runtime::Current()->GetImtUnimplementedMethod()); 2319 new_class->PopulateEmbeddedImtAndVTable(&hs2); 2320 } 2321 mirror::Class::SetStatus(new_class, mirror::Class::kStatusInitialized, self); 2322 // don't need to set new_class->SetObjectSize(..) 2323 // because Object::SizeOf delegates to Array::SizeOf 2324 2325 2326 // All arrays have java/lang/Cloneable and java/io/Serializable as 2327 // interfaces. We need to set that up here, so that stuff like 2328 // "instanceof" works right. 2329 // 2330 // Note: The GC could run during the call to FindSystemClass, 2331 // so we need to make sure the class object is GC-valid while we're in 2332 // there. Do this by clearing the interface list so the GC will just 2333 // think that the entries are null. 2334 2335 2336 // Use the single, global copies of "interfaces" and "iftable" 2337 // (remember not to free them for arrays). 2338 { 2339 mirror::IfTable* array_iftable = array_iftable_.Read(); 2340 CHECK(array_iftable != nullptr); 2341 new_class->SetIfTable(array_iftable); 2342 } 2343 2344 // Inherit access flags from the component type. 2345 int access_flags = new_class->GetComponentType()->GetAccessFlags(); 2346 // Lose any implementation detail flags; in particular, arrays aren't finalizable. 2347 access_flags &= kAccJavaFlagsMask; 2348 // Arrays can't be used as a superclass or interface, so we want to add "abstract final" 2349 // and remove "interface". 2350 access_flags |= kAccAbstract | kAccFinal; 2351 access_flags &= ~kAccInterface; 2352 2353 new_class->SetAccessFlags(access_flags); 2354 2355 mirror::Class* existing = InsertClass(descriptor, new_class.Get(), hash); 2356 if (existing == nullptr) { 2357 return new_class.Get(); 2358 } 2359 // Another thread must have loaded the class after we 2360 // started but before we finished. Abandon what we've 2361 // done. 2362 // 2363 // (Yes, this happens.) 2364 2365 return existing; 2366} 2367 2368mirror::Class* ClassLinker::FindPrimitiveClass(char type) { 2369 switch (type) { 2370 case 'B': 2371 return GetClassRoot(kPrimitiveByte); 2372 case 'C': 2373 return GetClassRoot(kPrimitiveChar); 2374 case 'D': 2375 return GetClassRoot(kPrimitiveDouble); 2376 case 'F': 2377 return GetClassRoot(kPrimitiveFloat); 2378 case 'I': 2379 return GetClassRoot(kPrimitiveInt); 2380 case 'J': 2381 return GetClassRoot(kPrimitiveLong); 2382 case 'S': 2383 return GetClassRoot(kPrimitiveShort); 2384 case 'Z': 2385 return GetClassRoot(kPrimitiveBoolean); 2386 case 'V': 2387 return GetClassRoot(kPrimitiveVoid); 2388 default: 2389 break; 2390 } 2391 std::string printable_type(PrintableChar(type)); 2392 ThrowNoClassDefFoundError("Not a primitive type: %s", printable_type.c_str()); 2393 return nullptr; 2394} 2395 2396mirror::Class* ClassLinker::InsertClass(const char* descriptor, mirror::Class* klass, 2397 size_t hash) { 2398 if (VLOG_IS_ON(class_linker)) { 2399 mirror::DexCache* dex_cache = klass->GetDexCache(); 2400 std::string source; 2401 if (dex_cache != nullptr) { 2402 source += " from "; 2403 source += dex_cache->GetLocation()->ToModifiedUtf8(); 2404 } 2405 LOG(INFO) << "Loaded class " << descriptor << source; 2406 } 2407 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2408 mirror::Class* existing = LookupClassFromTableLocked(descriptor, klass->GetClassLoader(), hash); 2409 if (existing != nullptr) { 2410 return existing; 2411 } 2412 if (kIsDebugBuild && !klass->IsTemp() && klass->GetClassLoader() == nullptr && 2413 dex_cache_image_class_lookup_required_) { 2414 // Check a class loaded with the system class loader matches one in the image if the class 2415 // is in the image. 2416 existing = LookupClassFromImage(descriptor); 2417 if (existing != nullptr) { 2418 CHECK_EQ(klass, existing); 2419 } 2420 } 2421 VerifyObject(klass); 2422 class_table_.InsertWithHash(GcRoot<mirror::Class>(klass), hash); 2423 if (log_new_class_table_roots_) { 2424 new_class_roots_.push_back(GcRoot<mirror::Class>(klass)); 2425 } 2426 return nullptr; 2427} 2428 2429mirror::Class* ClassLinker::UpdateClass(const char* descriptor, mirror::Class* klass, 2430 size_t hash) { 2431 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2432 auto existing_it = class_table_.FindWithHash(std::make_pair(descriptor, klass->GetClassLoader()), 2433 hash); 2434 if (existing_it == class_table_.end()) { 2435 CHECK(klass->IsProxyClass()); 2436 return nullptr; 2437 } 2438 2439 mirror::Class* existing = existing_it->Read(); 2440 CHECK_NE(existing, klass) << descriptor; 2441 CHECK(!existing->IsResolved()) << descriptor; 2442 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusResolving) << descriptor; 2443 2444 CHECK(!klass->IsTemp()) << descriptor; 2445 if (kIsDebugBuild && klass->GetClassLoader() == nullptr && 2446 dex_cache_image_class_lookup_required_) { 2447 // Check a class loaded with the system class loader matches one in the image if the class 2448 // is in the image. 2449 existing = LookupClassFromImage(descriptor); 2450 if (existing != nullptr) { 2451 CHECK_EQ(klass, existing) << descriptor; 2452 } 2453 } 2454 VerifyObject(klass); 2455 2456 // Update the element in the hash set. 2457 *existing_it = GcRoot<mirror::Class>(klass); 2458 if (log_new_class_table_roots_) { 2459 new_class_roots_.push_back(GcRoot<mirror::Class>(klass)); 2460 } 2461 2462 return existing; 2463} 2464 2465bool ClassLinker::RemoveClass(const char* descriptor, mirror::ClassLoader* class_loader) { 2466 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2467 auto pair = std::make_pair(descriptor, class_loader); 2468 auto it = class_table_.Find(pair); 2469 if (it != class_table_.end()) { 2470 class_table_.Erase(it); 2471 return true; 2472 } 2473 it = pre_zygote_class_table_.Find(pair); 2474 if (it != pre_zygote_class_table_.end()) { 2475 pre_zygote_class_table_.Erase(it); 2476 return true; 2477 } 2478 return false; 2479} 2480 2481mirror::Class* ClassLinker::LookupClass(Thread* self, const char* descriptor, size_t hash, 2482 mirror::ClassLoader* class_loader) { 2483 { 2484 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 2485 mirror::Class* result = LookupClassFromTableLocked(descriptor, class_loader, hash); 2486 if (result != nullptr) { 2487 return result; 2488 } 2489 } 2490 if (class_loader != nullptr || !dex_cache_image_class_lookup_required_) { 2491 return nullptr; 2492 } else { 2493 // Lookup failed but need to search dex_caches_. 2494 mirror::Class* result = LookupClassFromImage(descriptor); 2495 if (result != nullptr) { 2496 InsertClass(descriptor, result, hash); 2497 } else { 2498 // Searching the image dex files/caches failed, we don't want to get into this situation 2499 // often as map searches are faster, so after kMaxFailedDexCacheLookups move all image 2500 // classes into the class table. 2501 constexpr uint32_t kMaxFailedDexCacheLookups = 1000; 2502 if (++failed_dex_cache_class_lookups_ > kMaxFailedDexCacheLookups) { 2503 MoveImageClassesToClassTable(); 2504 } 2505 } 2506 return result; 2507 } 2508} 2509 2510mirror::Class* ClassLinker::LookupClassFromTableLocked(const char* descriptor, 2511 mirror::ClassLoader* class_loader, 2512 size_t hash) { 2513 auto descriptor_pair = std::make_pair(descriptor, class_loader); 2514 auto it = pre_zygote_class_table_.FindWithHash(descriptor_pair, hash); 2515 if (it == pre_zygote_class_table_.end()) { 2516 it = class_table_.FindWithHash(descriptor_pair, hash); 2517 if (it == class_table_.end()) { 2518 return nullptr; 2519 } 2520 } 2521 return it->Read(); 2522} 2523 2524static mirror::ObjectArray<mirror::DexCache>* GetImageDexCaches() 2525 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 2526 gc::space::ImageSpace* image = Runtime::Current()->GetHeap()->GetImageSpace(); 2527 CHECK(image != nullptr); 2528 mirror::Object* root = image->GetImageHeader().GetImageRoot(ImageHeader::kDexCaches); 2529 return root->AsObjectArray<mirror::DexCache>(); 2530} 2531 2532void ClassLinker::MoveImageClassesToClassTable() { 2533 Thread* self = Thread::Current(); 2534 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_); 2535 if (!dex_cache_image_class_lookup_required_) { 2536 return; // All dex cache classes are already in the class table. 2537 } 2538 ScopedAssertNoThreadSuspension ants(self, "Moving image classes to class table"); 2539 mirror::ObjectArray<mirror::DexCache>* dex_caches = GetImageDexCaches(); 2540 std::string temp; 2541 for (int32_t i = 0; i < dex_caches->GetLength(); i++) { 2542 mirror::DexCache* dex_cache = dex_caches->Get(i); 2543 mirror::ObjectArray<mirror::Class>* types = dex_cache->GetResolvedTypes(); 2544 for (int32_t j = 0; j < types->GetLength(); j++) { 2545 mirror::Class* klass = types->Get(j); 2546 if (klass != nullptr) { 2547 DCHECK(klass->GetClassLoader() == nullptr); 2548 const char* descriptor = klass->GetDescriptor(&temp); 2549 size_t hash = ComputeModifiedUtf8Hash(descriptor); 2550 mirror::Class* existing = LookupClassFromTableLocked(descriptor, nullptr, hash); 2551 if (existing != nullptr) { 2552 CHECK_EQ(existing, klass) << PrettyClassAndClassLoader(existing) << " != " 2553 << PrettyClassAndClassLoader(klass); 2554 } else { 2555 class_table_.Insert(GcRoot<mirror::Class>(klass)); 2556 if (log_new_class_table_roots_) { 2557 new_class_roots_.push_back(GcRoot<mirror::Class>(klass)); 2558 } 2559 } 2560 } 2561 } 2562 } 2563 dex_cache_image_class_lookup_required_ = false; 2564} 2565 2566void ClassLinker::MoveClassTableToPreZygote() { 2567 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2568 DCHECK(pre_zygote_class_table_.Empty()); 2569 pre_zygote_class_table_ = std::move(class_table_); 2570 class_table_.Clear(); 2571} 2572 2573mirror::Class* ClassLinker::LookupClassFromImage(const char* descriptor) { 2574 ScopedAssertNoThreadSuspension ants(Thread::Current(), "Image class lookup"); 2575 mirror::ObjectArray<mirror::DexCache>* dex_caches = GetImageDexCaches(); 2576 for (int32_t i = 0; i < dex_caches->GetLength(); ++i) { 2577 mirror::DexCache* dex_cache = dex_caches->Get(i); 2578 const DexFile* dex_file = dex_cache->GetDexFile(); 2579 // Try binary searching the string/type index. 2580 const DexFile::StringId* string_id = dex_file->FindStringId(descriptor); 2581 if (string_id != nullptr) { 2582 const DexFile::TypeId* type_id = 2583 dex_file->FindTypeId(dex_file->GetIndexForStringId(*string_id)); 2584 if (type_id != nullptr) { 2585 uint16_t type_idx = dex_file->GetIndexForTypeId(*type_id); 2586 mirror::Class* klass = dex_cache->GetResolvedType(type_idx); 2587 if (klass != nullptr) { 2588 return klass; 2589 } 2590 } 2591 } 2592 } 2593 return nullptr; 2594} 2595 2596void ClassLinker::LookupClasses(const char* descriptor, std::vector<mirror::Class*>& result) { 2597 result.clear(); 2598 if (dex_cache_image_class_lookup_required_) { 2599 MoveImageClassesToClassTable(); 2600 } 2601 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2602 while (true) { 2603 auto it = class_table_.Find(descriptor); 2604 if (it == class_table_.end()) { 2605 break; 2606 } 2607 result.push_back(it->Read()); 2608 class_table_.Erase(it); 2609 } 2610 for (mirror::Class* k : result) { 2611 class_table_.Insert(GcRoot<mirror::Class>(k)); 2612 } 2613 size_t pre_zygote_start = result.size(); 2614 // Now handle the pre zygote table. 2615 // Note: This dirties the pre-zygote table but shouldn't be an issue since LookupClasses is only 2616 // called from the debugger. 2617 while (true) { 2618 auto it = pre_zygote_class_table_.Find(descriptor); 2619 if (it == pre_zygote_class_table_.end()) { 2620 break; 2621 } 2622 result.push_back(it->Read()); 2623 pre_zygote_class_table_.Erase(it); 2624 } 2625 for (size_t i = pre_zygote_start; i < result.size(); ++i) { 2626 pre_zygote_class_table_.Insert(GcRoot<mirror::Class>(result[i])); 2627 } 2628} 2629 2630void ClassLinker::VerifyClass(Thread* self, Handle<mirror::Class> klass) { 2631 // TODO: assert that the monitor on the Class is held 2632 ObjectLock<mirror::Class> lock(self, klass); 2633 2634 // Don't attempt to re-verify if already sufficiently verified. 2635 if (klass->IsVerified()) { 2636 EnsurePreverifiedMethods(klass); 2637 return; 2638 } 2639 if (klass->IsCompileTimeVerified() && Runtime::Current()->IsAotCompiler()) { 2640 return; 2641 } 2642 2643 // The class might already be erroneous, for example at compile time if we attempted to verify 2644 // this class as a parent to another. 2645 if (klass->IsErroneous()) { 2646 ThrowEarlierClassFailure(klass.Get()); 2647 return; 2648 } 2649 2650 if (klass->GetStatus() == mirror::Class::kStatusResolved) { 2651 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerifying, self); 2652 } else { 2653 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime) 2654 << PrettyClass(klass.Get()); 2655 CHECK(!Runtime::Current()->IsAotCompiler()); 2656 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerifyingAtRuntime, self); 2657 } 2658 2659 // Skip verification if disabled. 2660 if (!Runtime::Current()->IsVerificationEnabled()) { 2661 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self); 2662 EnsurePreverifiedMethods(klass); 2663 return; 2664 } 2665 2666 // Verify super class. 2667 StackHandleScope<2> hs(self); 2668 Handle<mirror::Class> super(hs.NewHandle(klass->GetSuperClass())); 2669 if (super.Get() != nullptr) { 2670 // Acquire lock to prevent races on verifying the super class. 2671 ObjectLock<mirror::Class> super_lock(self, super); 2672 2673 if (!super->IsVerified() && !super->IsErroneous()) { 2674 VerifyClass(self, super); 2675 } 2676 if (!super->IsCompileTimeVerified()) { 2677 std::string error_msg( 2678 StringPrintf("Rejecting class %s that attempts to sub-class erroneous class %s", 2679 PrettyDescriptor(klass.Get()).c_str(), 2680 PrettyDescriptor(super.Get()).c_str())); 2681 LOG(WARNING) << error_msg << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8(); 2682 Handle<mirror::Throwable> cause(hs.NewHandle(self->GetException())); 2683 if (cause.Get() != nullptr) { 2684 self->ClearException(); 2685 } 2686 ThrowVerifyError(klass.Get(), "%s", error_msg.c_str()); 2687 if (cause.Get() != nullptr) { 2688 self->GetException()->SetCause(cause.Get()); 2689 } 2690 ClassReference ref(klass->GetDexCache()->GetDexFile(), klass->GetDexClassDefIndex()); 2691 if (Runtime::Current()->IsAotCompiler()) { 2692 Runtime::Current()->GetCompilerCallbacks()->ClassRejected(ref); 2693 } 2694 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 2695 return; 2696 } 2697 } 2698 2699 // Try to use verification information from the oat file, otherwise do runtime verification. 2700 const DexFile& dex_file = *klass->GetDexCache()->GetDexFile(); 2701 mirror::Class::Status oat_file_class_status(mirror::Class::kStatusNotReady); 2702 bool preverified = VerifyClassUsingOatFile(dex_file, klass.Get(), oat_file_class_status); 2703 if (oat_file_class_status == mirror::Class::kStatusError) { 2704 VLOG(class_linker) << "Skipping runtime verification of erroneous class " 2705 << PrettyDescriptor(klass.Get()) << " in " 2706 << klass->GetDexCache()->GetLocation()->ToModifiedUtf8(); 2707 ThrowVerifyError(klass.Get(), "Rejecting class %s because it failed compile-time verification", 2708 PrettyDescriptor(klass.Get()).c_str()); 2709 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 2710 return; 2711 } 2712 verifier::MethodVerifier::FailureKind verifier_failure = verifier::MethodVerifier::kNoFailure; 2713 std::string error_msg; 2714 if (!preverified) { 2715 verifier_failure = verifier::MethodVerifier::VerifyClass(self, klass.Get(), 2716 Runtime::Current()->IsAotCompiler(), 2717 &error_msg); 2718 } 2719 if (preverified || verifier_failure != verifier::MethodVerifier::kHardFailure) { 2720 if (!preverified && verifier_failure != verifier::MethodVerifier::kNoFailure) { 2721 VLOG(class_linker) << "Soft verification failure in class " << PrettyDescriptor(klass.Get()) 2722 << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8() 2723 << " because: " << error_msg; 2724 } 2725 self->AssertNoPendingException(); 2726 // Make sure all classes referenced by catch blocks are resolved. 2727 ResolveClassExceptionHandlerTypes(dex_file, klass); 2728 if (verifier_failure == verifier::MethodVerifier::kNoFailure) { 2729 // Even though there were no verifier failures we need to respect whether the super-class 2730 // was verified or requiring runtime reverification. 2731 if (super.Get() == nullptr || super->IsVerified()) { 2732 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self); 2733 } else { 2734 CHECK_EQ(super->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime); 2735 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetryVerificationAtRuntime, self); 2736 // Pretend a soft failure occured so that we don't consider the class verified below. 2737 verifier_failure = verifier::MethodVerifier::kSoftFailure; 2738 } 2739 } else { 2740 CHECK_EQ(verifier_failure, verifier::MethodVerifier::kSoftFailure); 2741 // Soft failures at compile time should be retried at runtime. Soft 2742 // failures at runtime will be handled by slow paths in the generated 2743 // code. Set status accordingly. 2744 if (Runtime::Current()->IsAotCompiler()) { 2745 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetryVerificationAtRuntime, self); 2746 } else { 2747 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self); 2748 // As this is a fake verified status, make sure the methods are _not_ marked preverified 2749 // later. 2750 klass->SetPreverified(); 2751 } 2752 } 2753 } else { 2754 LOG(WARNING) << "Verification failed on class " << PrettyDescriptor(klass.Get()) 2755 << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8() 2756 << " because: " << error_msg; 2757 self->AssertNoPendingException(); 2758 ThrowVerifyError(klass.Get(), "%s", error_msg.c_str()); 2759 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 2760 } 2761 if (preverified || verifier_failure == verifier::MethodVerifier::kNoFailure) { 2762 // Class is verified so we don't need to do any access check on its methods. 2763 // Let the interpreter know it by setting the kAccPreverified flag onto each 2764 // method. 2765 // Note: we're going here during compilation and at runtime. When we set the 2766 // kAccPreverified flag when compiling image classes, the flag is recorded 2767 // in the image and is set when loading the image. 2768 EnsurePreverifiedMethods(klass); 2769 } 2770} 2771 2772void ClassLinker::EnsurePreverifiedMethods(Handle<mirror::Class> klass) { 2773 if (!klass->IsPreverified()) { 2774 klass->SetPreverifiedFlagOnAllMethods(); 2775 klass->SetPreverified(); 2776 } 2777} 2778 2779bool ClassLinker::VerifyClassUsingOatFile(const DexFile& dex_file, mirror::Class* klass, 2780 mirror::Class::Status& oat_file_class_status) { 2781 // If we're compiling, we can only verify the class using the oat file if 2782 // we are not compiling the image or if the class we're verifying is not part of 2783 // the app. In other words, we will only check for preverification of bootclasspath 2784 // classes. 2785 if (Runtime::Current()->IsAotCompiler()) { 2786 // Are we compiling the bootclasspath? 2787 if (Runtime::Current()->GetCompilerCallbacks()->IsBootImage()) { 2788 return false; 2789 } 2790 // We are compiling an app (not the image). 2791 2792 // Is this an app class? (I.e. not a bootclasspath class) 2793 if (klass->GetClassLoader() != nullptr) { 2794 return false; 2795 } 2796 } 2797 2798 const OatFile::OatDexFile* oat_dex_file = FindOpenedOatDexFileForDexFile(dex_file); 2799 // In case we run without an image there won't be a backing oat file. 2800 if (oat_dex_file == nullptr) { 2801 return false; 2802 } 2803 2804 // We may be running with a preopted oat file but without image. In this case, 2805 // we don't skip verification of preverified classes to ensure we initialize 2806 // dex caches with all types resolved during verification. 2807 // We need to trust image classes, as these might be coming out of a pre-opted, quickened boot 2808 // image (that we just failed loading), and the verifier can't be run on quickened opcodes when 2809 // the runtime isn't started. On the other hand, app classes can be re-verified even if they are 2810 // already pre-opted, as then the runtime is started. 2811 if (!Runtime::Current()->IsAotCompiler() && 2812 !Runtime::Current()->GetHeap()->HasImageSpace() && 2813 klass->GetClassLoader() != nullptr) { 2814 return false; 2815 } 2816 2817 uint16_t class_def_index = klass->GetDexClassDefIndex(); 2818 oat_file_class_status = oat_dex_file->GetOatClass(class_def_index).GetStatus(); 2819 if (oat_file_class_status == mirror::Class::kStatusVerified || 2820 oat_file_class_status == mirror::Class::kStatusInitialized) { 2821 return true; 2822 } 2823 if (oat_file_class_status == mirror::Class::kStatusRetryVerificationAtRuntime) { 2824 // Compile time verification failed with a soft error. Compile time verification can fail 2825 // because we have incomplete type information. Consider the following: 2826 // class ... { 2827 // Foo x; 2828 // .... () { 2829 // if (...) { 2830 // v1 gets assigned a type of resolved class Foo 2831 // } else { 2832 // v1 gets assigned a type of unresolved class Bar 2833 // } 2834 // iput x = v1 2835 // } } 2836 // when we merge v1 following the if-the-else it results in Conflict 2837 // (see verifier::RegType::Merge) as we can't know the type of Bar and we could possibly be 2838 // allowing an unsafe assignment to the field x in the iput (javac may have compiled this as 2839 // it knew Bar was a sub-class of Foo, but for us this may have been moved into a separate apk 2840 // at compile time). 2841 return false; 2842 } 2843 if (oat_file_class_status == mirror::Class::kStatusError) { 2844 // Compile time verification failed with a hard error. This is caused by invalid instructions 2845 // in the class. These errors are unrecoverable. 2846 return false; 2847 } 2848 if (oat_file_class_status == mirror::Class::kStatusNotReady) { 2849 // Status is uninitialized if we couldn't determine the status at compile time, for example, 2850 // not loading the class. 2851 // TODO: when the verifier doesn't rely on Class-es failing to resolve/load the type hierarchy 2852 // isn't a problem and this case shouldn't occur 2853 return false; 2854 } 2855 std::string temp; 2856 LOG(FATAL) << "Unexpected class status: " << oat_file_class_status 2857 << " " << dex_file.GetLocation() << " " << PrettyClass(klass) << " " 2858 << klass->GetDescriptor(&temp); 2859 UNREACHABLE(); 2860} 2861 2862void ClassLinker::ResolveClassExceptionHandlerTypes(const DexFile& dex_file, 2863 Handle<mirror::Class> klass) { 2864 for (size_t i = 0; i < klass->NumDirectMethods(); i++) { 2865 ResolveMethodExceptionHandlerTypes(dex_file, klass->GetDirectMethod(i)); 2866 } 2867 for (size_t i = 0; i < klass->NumVirtualMethods(); i++) { 2868 ResolveMethodExceptionHandlerTypes(dex_file, klass->GetVirtualMethod(i)); 2869 } 2870} 2871 2872void ClassLinker::ResolveMethodExceptionHandlerTypes(const DexFile& dex_file, 2873 mirror::ArtMethod* method) { 2874 // similar to DexVerifier::ScanTryCatchBlocks and dex2oat's ResolveExceptionsForMethod. 2875 const DexFile::CodeItem* code_item = dex_file.GetCodeItem(method->GetCodeItemOffset()); 2876 if (code_item == nullptr) { 2877 return; // native or abstract method 2878 } 2879 if (code_item->tries_size_ == 0) { 2880 return; // nothing to process 2881 } 2882 const uint8_t* handlers_ptr = DexFile::GetCatchHandlerData(*code_item, 0); 2883 uint32_t handlers_size = DecodeUnsignedLeb128(&handlers_ptr); 2884 ClassLinker* linker = Runtime::Current()->GetClassLinker(); 2885 for (uint32_t idx = 0; idx < handlers_size; idx++) { 2886 CatchHandlerIterator iterator(handlers_ptr); 2887 for (; iterator.HasNext(); iterator.Next()) { 2888 // Ensure exception types are resolved so that they don't need resolution to be delivered, 2889 // unresolved exception types will be ignored by exception delivery 2890 if (iterator.GetHandlerTypeIndex() != DexFile::kDexNoIndex16) { 2891 mirror::Class* exception_type = linker->ResolveType(iterator.GetHandlerTypeIndex(), method); 2892 if (exception_type == nullptr) { 2893 DCHECK(Thread::Current()->IsExceptionPending()); 2894 Thread::Current()->ClearException(); 2895 } 2896 } 2897 } 2898 handlers_ptr = iterator.EndDataPointer(); 2899 } 2900} 2901 2902static void CheckProxyConstructor(mirror::ArtMethod* constructor); 2903static void CheckProxyMethod(Handle<mirror::ArtMethod> method, 2904 Handle<mirror::ArtMethod> prototype); 2905 2906mirror::Class* ClassLinker::CreateProxyClass(ScopedObjectAccessAlreadyRunnable& soa, jstring name, 2907 jobjectArray interfaces, jobject loader, 2908 jobjectArray methods, jobjectArray throws) { 2909 Thread* self = soa.Self(); 2910 StackHandleScope<8> hs(self); 2911 MutableHandle<mirror::Class> klass(hs.NewHandle( 2912 AllocClass(self, GetClassRoot(kJavaLangClass), sizeof(mirror::Class)))); 2913 if (klass.Get() == nullptr) { 2914 CHECK(self->IsExceptionPending()); // OOME. 2915 return nullptr; 2916 } 2917 DCHECK(klass->GetClass() != nullptr); 2918 klass->SetObjectSize(sizeof(mirror::Proxy)); 2919 // Set the class access flags incl. preverified, so we do not try to set the flag on the methods. 2920 klass->SetAccessFlags(kAccClassIsProxy | kAccPublic | kAccFinal | kAccPreverified); 2921 klass->SetClassLoader(soa.Decode<mirror::ClassLoader*>(loader)); 2922 DCHECK_EQ(klass->GetPrimitiveType(), Primitive::kPrimNot); 2923 klass->SetName(soa.Decode<mirror::String*>(name)); 2924 mirror::Class* proxy_class = GetClassRoot(kJavaLangReflectProxy); 2925 klass->SetDexCache(proxy_class->GetDexCache()); 2926 mirror::Class::SetStatus(klass, mirror::Class::kStatusIdx, self); 2927 2928 // Instance fields are inherited, but we add a couple of static fields... 2929 { 2930 mirror::ObjectArray<mirror::ArtField>* sfields = AllocArtFieldArray(self, 2); 2931 if (UNLIKELY(sfields == nullptr)) { 2932 CHECK(self->IsExceptionPending()); // OOME. 2933 return nullptr; 2934 } 2935 klass->SetSFields(sfields); 2936 } 2937 // 1. Create a static field 'interfaces' that holds the _declared_ interfaces implemented by 2938 // our proxy, so Class.getInterfaces doesn't return the flattened set. 2939 Handle<mirror::ArtField> interfaces_sfield(hs.NewHandle(AllocArtField(self))); 2940 if (UNLIKELY(interfaces_sfield.Get() == nullptr)) { 2941 CHECK(self->IsExceptionPending()); // OOME. 2942 return nullptr; 2943 } 2944 klass->SetStaticField(0, interfaces_sfield.Get()); 2945 interfaces_sfield->SetDexFieldIndex(0); 2946 interfaces_sfield->SetDeclaringClass(klass.Get()); 2947 interfaces_sfield->SetAccessFlags(kAccStatic | kAccPublic | kAccFinal); 2948 // 2. Create a static field 'throws' that holds exceptions thrown by our methods. 2949 Handle<mirror::ArtField> throws_sfield(hs.NewHandle(AllocArtField(self))); 2950 if (UNLIKELY(throws_sfield.Get() == nullptr)) { 2951 CHECK(self->IsExceptionPending()); // OOME. 2952 return nullptr; 2953 } 2954 klass->SetStaticField(1, throws_sfield.Get()); 2955 throws_sfield->SetDexFieldIndex(1); 2956 throws_sfield->SetDeclaringClass(klass.Get()); 2957 throws_sfield->SetAccessFlags(kAccStatic | kAccPublic | kAccFinal); 2958 2959 // Proxies have 1 direct method, the constructor 2960 { 2961 mirror::ObjectArray<mirror::ArtMethod>* directs = AllocArtMethodArray(self, 1); 2962 if (UNLIKELY(directs == nullptr)) { 2963 CHECK(self->IsExceptionPending()); // OOME. 2964 return nullptr; 2965 } 2966 klass->SetDirectMethods(directs); 2967 mirror::ArtMethod* constructor = CreateProxyConstructor(self, klass, proxy_class); 2968 if (UNLIKELY(constructor == nullptr)) { 2969 CHECK(self->IsExceptionPending()); // OOME. 2970 return nullptr; 2971 } 2972 klass->SetDirectMethod(0, constructor); 2973 } 2974 2975 // Create virtual method using specified prototypes. 2976 size_t num_virtual_methods = 2977 soa.Decode<mirror::ObjectArray<mirror::ArtMethod>*>(methods)->GetLength(); 2978 { 2979 mirror::ObjectArray<mirror::ArtMethod>* virtuals = AllocArtMethodArray(self, 2980 num_virtual_methods); 2981 if (UNLIKELY(virtuals == nullptr)) { 2982 CHECK(self->IsExceptionPending()); // OOME. 2983 return nullptr; 2984 } 2985 klass->SetVirtualMethods(virtuals); 2986 } 2987 for (size_t i = 0; i < num_virtual_methods; ++i) { 2988 StackHandleScope<1> hs2(self); 2989 mirror::ObjectArray<mirror::ArtMethod>* decoded_methods = 2990 soa.Decode<mirror::ObjectArray<mirror::ArtMethod>*>(methods); 2991 Handle<mirror::ArtMethod> prototype(hs2.NewHandle(decoded_methods->Get(i))); 2992 mirror::ArtMethod* clone = CreateProxyMethod(self, klass, prototype); 2993 if (UNLIKELY(clone == nullptr)) { 2994 CHECK(self->IsExceptionPending()); // OOME. 2995 return nullptr; 2996 } 2997 klass->SetVirtualMethod(i, clone); 2998 } 2999 3000 klass->SetSuperClass(proxy_class); // The super class is java.lang.reflect.Proxy 3001 mirror::Class::SetStatus(klass, mirror::Class::kStatusLoaded, self); // Now effectively in the loaded state. 3002 self->AssertNoPendingException(); 3003 3004 std::string descriptor(GetDescriptorForProxy(klass.Get())); 3005 mirror::Class* new_class = nullptr; 3006 { 3007 // Must hold lock on object when resolved. 3008 ObjectLock<mirror::Class> resolution_lock(self, klass); 3009 // Link the fields and virtual methods, creating vtable and iftables 3010 Handle<mirror::ObjectArray<mirror::Class> > h_interfaces( 3011 hs.NewHandle(soa.Decode<mirror::ObjectArray<mirror::Class>*>(interfaces))); 3012 if (!LinkClass(self, descriptor.c_str(), klass, h_interfaces, &new_class)) { 3013 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3014 return nullptr; 3015 } 3016 } 3017 3018 CHECK(klass->IsRetired()); 3019 CHECK_NE(klass.Get(), new_class); 3020 klass.Assign(new_class); 3021 3022 CHECK_EQ(interfaces_sfield->GetDeclaringClass(), new_class); 3023 interfaces_sfield->SetObject<false>(klass.Get(), 3024 soa.Decode<mirror::ObjectArray<mirror::Class>*>(interfaces)); 3025 CHECK_EQ(throws_sfield->GetDeclaringClass(), new_class); 3026 throws_sfield->SetObject<false>(klass.Get(), 3027 soa.Decode<mirror::ObjectArray<mirror::ObjectArray<mirror::Class> >*>(throws)); 3028 3029 { 3030 // Lock on klass is released. Lock new class object. 3031 ObjectLock<mirror::Class> initialization_lock(self, klass); 3032 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitialized, self); 3033 } 3034 3035 // sanity checks 3036 if (kIsDebugBuild) { 3037 CHECK(klass->GetIFields() == nullptr); 3038 CheckProxyConstructor(klass->GetDirectMethod(0)); 3039 for (size_t i = 0; i < num_virtual_methods; ++i) { 3040 StackHandleScope<2> hs2(self); 3041 mirror::ObjectArray<mirror::ArtMethod>* decoded_methods = 3042 soa.Decode<mirror::ObjectArray<mirror::ArtMethod>*>(methods); 3043 Handle<mirror::ArtMethod> prototype(hs2.NewHandle(decoded_methods->Get(i))); 3044 Handle<mirror::ArtMethod> virtual_method(hs2.NewHandle(klass->GetVirtualMethod(i))); 3045 CheckProxyMethod(virtual_method, prototype); 3046 } 3047 3048 mirror::String* decoded_name = soa.Decode<mirror::String*>(name); 3049 std::string interfaces_field_name(StringPrintf("java.lang.Class[] %s.interfaces", 3050 decoded_name->ToModifiedUtf8().c_str())); 3051 CHECK_EQ(PrettyField(klass->GetStaticField(0)), interfaces_field_name); 3052 3053 std::string throws_field_name(StringPrintf("java.lang.Class[][] %s.throws", 3054 decoded_name->ToModifiedUtf8().c_str())); 3055 CHECK_EQ(PrettyField(klass->GetStaticField(1)), throws_field_name); 3056 3057 CHECK_EQ(klass.Get()->GetInterfaces(), 3058 soa.Decode<mirror::ObjectArray<mirror::Class>*>(interfaces)); 3059 CHECK_EQ(klass.Get()->GetThrows(), 3060 soa.Decode<mirror::ObjectArray<mirror::ObjectArray<mirror::Class>>*>(throws)); 3061 } 3062 mirror::Class* existing = InsertClass(descriptor.c_str(), klass.Get(), 3063 ComputeModifiedUtf8Hash(descriptor.c_str())); 3064 CHECK(existing == nullptr); 3065 return klass.Get(); 3066} 3067 3068std::string ClassLinker::GetDescriptorForProxy(mirror::Class* proxy_class) { 3069 DCHECK(proxy_class->IsProxyClass()); 3070 mirror::String* name = proxy_class->GetName(); 3071 DCHECK(name != nullptr); 3072 return DotToDescriptor(name->ToModifiedUtf8().c_str()); 3073} 3074 3075mirror::ArtMethod* ClassLinker::FindMethodForProxy(mirror::Class* proxy_class, 3076 mirror::ArtMethod* proxy_method) { 3077 DCHECK(proxy_class->IsProxyClass()); 3078 DCHECK(proxy_method->IsProxyMethod()); 3079 // Locate the dex cache of the original interface/Object 3080 mirror::DexCache* dex_cache = nullptr; 3081 { 3082 ReaderMutexLock mu(Thread::Current(), dex_lock_); 3083 for (size_t i = 0; i != dex_caches_.size(); ++i) { 3084 mirror::DexCache* a_dex_cache = GetDexCache(i); 3085 if (proxy_method->HasSameDexCacheResolvedTypes(a_dex_cache->GetResolvedTypes())) { 3086 dex_cache = a_dex_cache; 3087 break; 3088 } 3089 } 3090 } 3091 CHECK(dex_cache != nullptr); 3092 uint32_t method_idx = proxy_method->GetDexMethodIndex(); 3093 mirror::ArtMethod* resolved_method = dex_cache->GetResolvedMethod(method_idx); 3094 CHECK(resolved_method != nullptr); 3095 return resolved_method; 3096} 3097 3098 3099mirror::ArtMethod* ClassLinker::CreateProxyConstructor(Thread* self, 3100 Handle<mirror::Class> klass, 3101 mirror::Class* proxy_class) { 3102 // Create constructor for Proxy that must initialize h 3103 mirror::ObjectArray<mirror::ArtMethod>* proxy_direct_methods = 3104 proxy_class->GetDirectMethods(); 3105 CHECK_EQ(proxy_direct_methods->GetLength(), 16); 3106 mirror::ArtMethod* proxy_constructor = proxy_direct_methods->Get(2); 3107 // Ensure constructor is in dex cache so that we can use the dex cache to look up the overridden 3108 // constructor method. 3109 proxy_class->GetDexCache()->SetResolvedMethod(proxy_constructor->GetDexMethodIndex(), 3110 proxy_constructor); 3111 // Clone the existing constructor of Proxy (our constructor would just invoke it so steal its 3112 // code_ too) 3113 mirror::ArtMethod* constructor = down_cast<mirror::ArtMethod*>(proxy_constructor->Clone(self)); 3114 if (constructor == nullptr) { 3115 CHECK(self->IsExceptionPending()); // OOME. 3116 return nullptr; 3117 } 3118 // Make this constructor public and fix the class to be our Proxy version 3119 constructor->SetAccessFlags((constructor->GetAccessFlags() & ~kAccProtected) | kAccPublic); 3120 constructor->SetDeclaringClass(klass.Get()); 3121 return constructor; 3122} 3123 3124static void CheckProxyConstructor(mirror::ArtMethod* constructor) 3125 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3126 CHECK(constructor->IsConstructor()); 3127 CHECK_STREQ(constructor->GetName(), "<init>"); 3128 CHECK_STREQ(constructor->GetSignature().ToString().c_str(), 3129 "(Ljava/lang/reflect/InvocationHandler;)V"); 3130 DCHECK(constructor->IsPublic()); 3131} 3132 3133mirror::ArtMethod* ClassLinker::CreateProxyMethod(Thread* self, 3134 Handle<mirror::Class> klass, 3135 Handle<mirror::ArtMethod> prototype) { 3136 // Ensure prototype is in dex cache so that we can use the dex cache to look up the overridden 3137 // prototype method 3138 prototype->GetDeclaringClass()->GetDexCache()->SetResolvedMethod(prototype->GetDexMethodIndex(), 3139 prototype.Get()); 3140 // We steal everything from the prototype (such as DexCache, invoke stub, etc.) then specialize 3141 // as necessary 3142 mirror::ArtMethod* method = down_cast<mirror::ArtMethod*>(prototype->Clone(self)); 3143 if (UNLIKELY(method == nullptr)) { 3144 CHECK(self->IsExceptionPending()); // OOME. 3145 return nullptr; 3146 } 3147 3148 // Set class to be the concrete proxy class and clear the abstract flag, modify exceptions to 3149 // the intersection of throw exceptions as defined in Proxy 3150 method->SetDeclaringClass(klass.Get()); 3151 method->SetAccessFlags((method->GetAccessFlags() & ~kAccAbstract) | kAccFinal); 3152 3153 // At runtime the method looks like a reference and argument saving method, clone the code 3154 // related parameters from this method. 3155 method->SetEntryPointFromQuickCompiledCode(GetQuickProxyInvokeHandler()); 3156 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 3157 3158 return method; 3159} 3160 3161static void CheckProxyMethod(Handle<mirror::ArtMethod> method, 3162 Handle<mirror::ArtMethod> prototype) 3163 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3164 // Basic sanity 3165 CHECK(!prototype->IsFinal()); 3166 CHECK(method->IsFinal()); 3167 CHECK(!method->IsAbstract()); 3168 3169 // The proxy method doesn't have its own dex cache or dex file and so it steals those of its 3170 // interface prototype. The exception to this are Constructors and the Class of the Proxy itself. 3171 CHECK(prototype->HasSameDexCacheResolvedMethods(method.Get())); 3172 CHECK(prototype->HasSameDexCacheResolvedTypes(method.Get())); 3173 CHECK_EQ(prototype->GetDexMethodIndex(), method->GetDexMethodIndex()); 3174 3175 CHECK_STREQ(method->GetName(), prototype->GetName()); 3176 CHECK_STREQ(method->GetShorty(), prototype->GetShorty()); 3177 // More complex sanity - via dex cache 3178 CHECK_EQ(method->GetInterfaceMethodIfProxy()->GetReturnType(), prototype->GetReturnType()); 3179} 3180 3181static bool CanWeInitializeClass(mirror::Class* klass, bool can_init_statics, 3182 bool can_init_parents) 3183 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3184 if (can_init_statics && can_init_parents) { 3185 return true; 3186 } 3187 if (!can_init_statics) { 3188 // Check if there's a class initializer. 3189 mirror::ArtMethod* clinit = klass->FindClassInitializer(); 3190 if (clinit != nullptr) { 3191 return false; 3192 } 3193 // Check if there are encoded static values needing initialization. 3194 if (klass->NumStaticFields() != 0) { 3195 const DexFile::ClassDef* dex_class_def = klass->GetClassDef(); 3196 DCHECK(dex_class_def != nullptr); 3197 if (dex_class_def->static_values_off_ != 0) { 3198 return false; 3199 } 3200 } 3201 } 3202 if (!klass->IsInterface() && klass->HasSuperClass()) { 3203 mirror::Class* super_class = klass->GetSuperClass(); 3204 if (!can_init_parents && !super_class->IsInitialized()) { 3205 return false; 3206 } else { 3207 if (!CanWeInitializeClass(super_class, can_init_statics, can_init_parents)) { 3208 return false; 3209 } 3210 } 3211 } 3212 return true; 3213} 3214 3215bool ClassLinker::InitializeClass(Thread* self, Handle<mirror::Class> klass, 3216 bool can_init_statics, bool can_init_parents) { 3217 // see JLS 3rd edition, 12.4.2 "Detailed Initialization Procedure" for the locking protocol 3218 3219 // Are we already initialized and therefore done? 3220 // Note: we differ from the JLS here as we don't do this under the lock, this is benign as 3221 // an initialized class will never change its state. 3222 if (klass->IsInitialized()) { 3223 return true; 3224 } 3225 3226 // Fast fail if initialization requires a full runtime. Not part of the JLS. 3227 if (!CanWeInitializeClass(klass.Get(), can_init_statics, can_init_parents)) { 3228 return false; 3229 } 3230 3231 self->AllowThreadSuspension(); 3232 uint64_t t0; 3233 { 3234 ObjectLock<mirror::Class> lock(self, klass); 3235 3236 // Re-check under the lock in case another thread initialized ahead of us. 3237 if (klass->IsInitialized()) { 3238 return true; 3239 } 3240 3241 // Was the class already found to be erroneous? Done under the lock to match the JLS. 3242 if (klass->IsErroneous()) { 3243 ThrowEarlierClassFailure(klass.Get()); 3244 VlogClassInitializationFailure(klass); 3245 return false; 3246 } 3247 3248 CHECK(klass->IsResolved()) << PrettyClass(klass.Get()) << ": state=" << klass->GetStatus(); 3249 3250 if (!klass->IsVerified()) { 3251 VerifyClass(self, klass); 3252 if (!klass->IsVerified()) { 3253 // We failed to verify, expect either the klass to be erroneous or verification failed at 3254 // compile time. 3255 if (klass->IsErroneous()) { 3256 CHECK(self->IsExceptionPending()); 3257 VlogClassInitializationFailure(klass); 3258 } else { 3259 CHECK(Runtime::Current()->IsAotCompiler()); 3260 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime); 3261 } 3262 return false; 3263 } else { 3264 self->AssertNoPendingException(); 3265 } 3266 } 3267 3268 // If the class is kStatusInitializing, either this thread is 3269 // initializing higher up the stack or another thread has beat us 3270 // to initializing and we need to wait. Either way, this 3271 // invocation of InitializeClass will not be responsible for 3272 // running <clinit> and will return. 3273 if (klass->GetStatus() == mirror::Class::kStatusInitializing) { 3274 // Could have got an exception during verification. 3275 if (self->IsExceptionPending()) { 3276 VlogClassInitializationFailure(klass); 3277 return false; 3278 } 3279 // We caught somebody else in the act; was it us? 3280 if (klass->GetClinitThreadId() == self->GetTid()) { 3281 // Yes. That's fine. Return so we can continue initializing. 3282 return true; 3283 } 3284 // No. That's fine. Wait for another thread to finish initializing. 3285 return WaitForInitializeClass(klass, self, lock); 3286 } 3287 3288 if (!ValidateSuperClassDescriptors(klass)) { 3289 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3290 return false; 3291 } 3292 self->AllowThreadSuspension(); 3293 3294 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusVerified) << PrettyClass(klass.Get()); 3295 3296 // From here out other threads may observe that we're initializing and so changes of state 3297 // require the a notification. 3298 klass->SetClinitThreadId(self->GetTid()); 3299 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitializing, self); 3300 3301 t0 = NanoTime(); 3302 } 3303 3304 // Initialize super classes, must be done while initializing for the JLS. 3305 if (!klass->IsInterface() && klass->HasSuperClass()) { 3306 mirror::Class* super_class = klass->GetSuperClass(); 3307 if (!super_class->IsInitialized()) { 3308 CHECK(!super_class->IsInterface()); 3309 CHECK(can_init_parents); 3310 StackHandleScope<1> hs(self); 3311 Handle<mirror::Class> handle_scope_super(hs.NewHandle(super_class)); 3312 bool super_initialized = InitializeClass(self, handle_scope_super, can_init_statics, true); 3313 if (!super_initialized) { 3314 // The super class was verified ahead of entering initializing, we should only be here if 3315 // the super class became erroneous due to initialization. 3316 CHECK(handle_scope_super->IsErroneous() && self->IsExceptionPending()) 3317 << "Super class initialization failed for " 3318 << PrettyDescriptor(handle_scope_super.Get()) 3319 << " that has unexpected status " << handle_scope_super->GetStatus() 3320 << "\nPending exception:\n" 3321 << (self->GetException() != nullptr ? self->GetException()->Dump() : ""); 3322 ObjectLock<mirror::Class> lock(self, klass); 3323 // Initialization failed because the super-class is erroneous. 3324 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3325 return false; 3326 } 3327 } 3328 } 3329 3330 const size_t num_static_fields = klass->NumStaticFields(); 3331 if (num_static_fields > 0) { 3332 const DexFile::ClassDef* dex_class_def = klass->GetClassDef(); 3333 CHECK(dex_class_def != nullptr); 3334 const DexFile& dex_file = klass->GetDexFile(); 3335 StackHandleScope<3> hs(self); 3336 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(klass->GetClassLoader())); 3337 Handle<mirror::DexCache> dex_cache(hs.NewHandle(klass->GetDexCache())); 3338 3339 // Eagerly fill in static fields so that the we don't have to do as many expensive 3340 // Class::FindStaticField in ResolveField. 3341 for (size_t i = 0; i < num_static_fields; ++i) { 3342 mirror::ArtField* field = klass->GetStaticField(i); 3343 const uint32_t field_idx = field->GetDexFieldIndex(); 3344 mirror::ArtField* resolved_field = dex_cache->GetResolvedField(field_idx); 3345 if (resolved_field == nullptr) { 3346 dex_cache->SetResolvedField(field_idx, field); 3347 } else { 3348 DCHECK_EQ(field, resolved_field); 3349 } 3350 } 3351 3352 EncodedStaticFieldValueIterator value_it(dex_file, &dex_cache, &class_loader, 3353 this, *dex_class_def); 3354 const uint8_t* class_data = dex_file.GetClassData(*dex_class_def); 3355 ClassDataItemIterator field_it(dex_file, class_data); 3356 if (value_it.HasNext()) { 3357 DCHECK(field_it.HasNextStaticField()); 3358 CHECK(can_init_statics); 3359 for ( ; value_it.HasNext(); value_it.Next(), field_it.Next()) { 3360 StackHandleScope<1> hs2(self); 3361 Handle<mirror::ArtField> field(hs2.NewHandle( 3362 ResolveField(dex_file, field_it.GetMemberIndex(), dex_cache, class_loader, true))); 3363 if (Runtime::Current()->IsActiveTransaction()) { 3364 value_it.ReadValueToField<true>(field); 3365 } else { 3366 value_it.ReadValueToField<false>(field); 3367 } 3368 DCHECK(!value_it.HasNext() || field_it.HasNextStaticField()); 3369 } 3370 } 3371 } 3372 3373 mirror::ArtMethod* clinit = klass->FindClassInitializer(); 3374 if (clinit != nullptr) { 3375 CHECK(can_init_statics); 3376 JValue result; 3377 clinit->Invoke(self, nullptr, 0, &result, "V"); 3378 } 3379 3380 self->AllowThreadSuspension(); 3381 uint64_t t1 = NanoTime(); 3382 3383 bool success = true; 3384 { 3385 ObjectLock<mirror::Class> lock(self, klass); 3386 3387 if (self->IsExceptionPending()) { 3388 WrapExceptionInInitializer(klass); 3389 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3390 success = false; 3391 } else if (Runtime::Current()->IsTransactionAborted()) { 3392 // The exception thrown when the transaction aborted has been caught and cleared 3393 // so we need to throw it again now. 3394 VLOG(compiler) << "Return from class initializer of " << PrettyDescriptor(klass.Get()) 3395 << " without exception while transaction was aborted: re-throw it now."; 3396 Runtime::Current()->ThrowInternalErrorForAbortedTransaction(self); 3397 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3398 success = false; 3399 } else { 3400 RuntimeStats* global_stats = Runtime::Current()->GetStats(); 3401 RuntimeStats* thread_stats = self->GetStats(); 3402 ++global_stats->class_init_count; 3403 ++thread_stats->class_init_count; 3404 global_stats->class_init_time_ns += (t1 - t0); 3405 thread_stats->class_init_time_ns += (t1 - t0); 3406 // Set the class as initialized except if failed to initialize static fields. 3407 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitialized, self); 3408 if (VLOG_IS_ON(class_linker)) { 3409 std::string temp; 3410 LOG(INFO) << "Initialized class " << klass->GetDescriptor(&temp) << " from " << 3411 klass->GetLocation(); 3412 } 3413 // Opportunistically set static method trampolines to their destination. 3414 FixupStaticTrampolines(klass.Get()); 3415 } 3416 } 3417 return success; 3418} 3419 3420bool ClassLinker::WaitForInitializeClass(Handle<mirror::Class> klass, Thread* self, 3421 ObjectLock<mirror::Class>& lock) 3422 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3423 while (true) { 3424 self->AssertNoPendingException(); 3425 CHECK(!klass->IsInitialized()); 3426 lock.WaitIgnoringInterrupts(); 3427 3428 // When we wake up, repeat the test for init-in-progress. If 3429 // there's an exception pending (only possible if 3430 // we were not using WaitIgnoringInterrupts), bail out. 3431 if (self->IsExceptionPending()) { 3432 WrapExceptionInInitializer(klass); 3433 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3434 return false; 3435 } 3436 // Spurious wakeup? Go back to waiting. 3437 if (klass->GetStatus() == mirror::Class::kStatusInitializing) { 3438 continue; 3439 } 3440 if (klass->GetStatus() == mirror::Class::kStatusVerified && 3441 Runtime::Current()->IsAotCompiler()) { 3442 // Compile time initialization failed. 3443 return false; 3444 } 3445 if (klass->IsErroneous()) { 3446 // The caller wants an exception, but it was thrown in a 3447 // different thread. Synthesize one here. 3448 ThrowNoClassDefFoundError("<clinit> failed for class %s; see exception in other thread", 3449 PrettyDescriptor(klass.Get()).c_str()); 3450 VlogClassInitializationFailure(klass); 3451 return false; 3452 } 3453 if (klass->IsInitialized()) { 3454 return true; 3455 } 3456 LOG(FATAL) << "Unexpected class status. " << PrettyClass(klass.Get()) << " is " 3457 << klass->GetStatus(); 3458 } 3459 UNREACHABLE(); 3460} 3461 3462static bool HasSameSignatureWithDifferentClassLoaders(Thread* self, 3463 Handle<mirror::ArtMethod> method1, 3464 Handle<mirror::ArtMethod> method2, 3465 std::string* error_msg) 3466 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3467 { 3468 StackHandleScope<1> hs(self); 3469 Handle<mirror::Class> return_type(hs.NewHandle(method1->GetReturnType())); 3470 mirror::Class* other_return_type = method2->GetReturnType(); 3471 // NOTE: return_type.Get() must be sequenced after method2->GetReturnType(). 3472 if (UNLIKELY(other_return_type != return_type.Get())) { 3473 *error_msg = StringPrintf("Return types mismatch: %s(%p) vs %s(%p)", 3474 PrettyClassAndClassLoader(return_type.Get()).c_str(), 3475 return_type.Get(), 3476 PrettyClassAndClassLoader(other_return_type).c_str(), 3477 other_return_type); 3478 return false; 3479 } 3480 } 3481 const DexFile::TypeList* types1 = method1->GetParameterTypeList(); 3482 const DexFile::TypeList* types2 = method2->GetParameterTypeList(); 3483 if (types1 == nullptr) { 3484 if (types2 != nullptr && types2->Size() != 0) { 3485 *error_msg = StringPrintf("Type list mismatch with %s", 3486 PrettyMethod(method2.Get(), true).c_str()); 3487 return false; 3488 } 3489 return true; 3490 } else if (UNLIKELY(types2 == nullptr)) { 3491 if (types1->Size() != 0) { 3492 *error_msg = StringPrintf("Type list mismatch with %s", 3493 PrettyMethod(method2.Get(), true).c_str()); 3494 return false; 3495 } 3496 return true; 3497 } 3498 uint32_t num_types = types1->Size(); 3499 if (UNLIKELY(num_types != types2->Size())) { 3500 *error_msg = StringPrintf("Type list mismatch with %s", 3501 PrettyMethod(method2.Get(), true).c_str()); 3502 return false; 3503 } 3504 for (uint32_t i = 0; i < num_types; ++i) { 3505 StackHandleScope<1> hs(self); 3506 Handle<mirror::Class> param_type(hs.NewHandle( 3507 method1->GetClassFromTypeIndex(types1->GetTypeItem(i).type_idx_, true))); 3508 mirror::Class* other_param_type = 3509 method2->GetClassFromTypeIndex(types2->GetTypeItem(i).type_idx_, true); 3510 // NOTE: param_type.Get() must be sequenced after method2->GetClassFromTypeIndex(...). 3511 if (UNLIKELY(param_type.Get() != other_param_type)) { 3512 *error_msg = StringPrintf("Parameter %u type mismatch: %s(%p) vs %s(%p)", 3513 i, 3514 PrettyClassAndClassLoader(param_type.Get()).c_str(), 3515 param_type.Get(), 3516 PrettyClassAndClassLoader(other_param_type).c_str(), 3517 other_param_type); 3518 return false; 3519 } 3520 } 3521 return true; 3522} 3523 3524 3525bool ClassLinker::ValidateSuperClassDescriptors(Handle<mirror::Class> klass) { 3526 if (klass->IsInterface()) { 3527 return true; 3528 } 3529 // Begin with the methods local to the superclass. 3530 Thread* self = Thread::Current(); 3531 StackHandleScope<2> hs(self); 3532 MutableHandle<mirror::ArtMethod> h_m(hs.NewHandle<mirror::ArtMethod>(nullptr)); 3533 MutableHandle<mirror::ArtMethod> super_h_m(hs.NewHandle<mirror::ArtMethod>(nullptr)); 3534 if (klass->HasSuperClass() && 3535 klass->GetClassLoader() != klass->GetSuperClass()->GetClassLoader()) { 3536 for (int i = klass->GetSuperClass()->GetVTableLength() - 1; i >= 0; --i) { 3537 h_m.Assign(klass->GetVTableEntry(i)); 3538 super_h_m.Assign(klass->GetSuperClass()->GetVTableEntry(i)); 3539 if (h_m.Get() != super_h_m.Get()) { 3540 std::string error_msg; 3541 if (!HasSameSignatureWithDifferentClassLoaders(self, h_m, super_h_m, &error_msg)) { 3542 ThrowLinkageError(klass.Get(), 3543 "Class %s method %s resolves differently in superclass %s: %s", 3544 PrettyDescriptor(klass.Get()).c_str(), 3545 PrettyMethod(h_m.Get()).c_str(), 3546 PrettyDescriptor(klass->GetSuperClass()).c_str(), 3547 error_msg.c_str()); 3548 return false; 3549 } 3550 } 3551 } 3552 } 3553 for (int32_t i = 0; i < klass->GetIfTableCount(); ++i) { 3554 if (klass->GetClassLoader() != klass->GetIfTable()->GetInterface(i)->GetClassLoader()) { 3555 uint32_t num_methods = klass->GetIfTable()->GetInterface(i)->NumVirtualMethods(); 3556 for (uint32_t j = 0; j < num_methods; ++j) { 3557 h_m.Assign(klass->GetIfTable()->GetMethodArray(i)->GetWithoutChecks(j)); 3558 super_h_m.Assign(klass->GetIfTable()->GetInterface(i)->GetVirtualMethod(j)); 3559 if (h_m.Get() != super_h_m.Get()) { 3560 std::string error_msg; 3561 if (!HasSameSignatureWithDifferentClassLoaders(self, h_m, super_h_m, &error_msg)) { 3562 ThrowLinkageError(klass.Get(), 3563 "Class %s method %s resolves differently in interface %s: %s", 3564 PrettyDescriptor(klass.Get()).c_str(), 3565 PrettyMethod(h_m.Get()).c_str(), 3566 PrettyDescriptor(klass->GetIfTable()->GetInterface(i)).c_str(), 3567 error_msg.c_str()); 3568 return false; 3569 } 3570 } 3571 } 3572 } 3573 } 3574 return true; 3575} 3576 3577bool ClassLinker::EnsureInitialized(Thread* self, Handle<mirror::Class> c, bool can_init_fields, 3578 bool can_init_parents) { 3579 DCHECK(c.Get() != nullptr); 3580 if (c->IsInitialized()) { 3581 EnsurePreverifiedMethods(c); 3582 return true; 3583 } 3584 const bool success = InitializeClass(self, c, can_init_fields, can_init_parents); 3585 if (!success) { 3586 if (can_init_fields && can_init_parents) { 3587 CHECK(self->IsExceptionPending()) << PrettyClass(c.Get()); 3588 } 3589 } else { 3590 self->AssertNoPendingException(); 3591 } 3592 return success; 3593} 3594 3595void ClassLinker::FixupTemporaryDeclaringClass(mirror::Class* temp_class, mirror::Class* new_class) { 3596 mirror::ObjectArray<mirror::ArtField>* fields = new_class->GetIFields(); 3597 if (fields != nullptr) { 3598 for (int index = 0; index < fields->GetLength(); index ++) { 3599 if (fields->Get(index)->GetDeclaringClass() == temp_class) { 3600 fields->Get(index)->SetDeclaringClass(new_class); 3601 } 3602 } 3603 } 3604 3605 fields = new_class->GetSFields(); 3606 if (fields != nullptr) { 3607 for (int index = 0; index < fields->GetLength(); index ++) { 3608 if (fields->Get(index)->GetDeclaringClass() == temp_class) { 3609 fields->Get(index)->SetDeclaringClass(new_class); 3610 } 3611 } 3612 } 3613 3614 mirror::ObjectArray<mirror::ArtMethod>* methods = new_class->GetDirectMethods(); 3615 if (methods != nullptr) { 3616 for (int index = 0; index < methods->GetLength(); index ++) { 3617 if (methods->Get(index)->GetDeclaringClass() == temp_class) { 3618 methods->Get(index)->SetDeclaringClass(new_class); 3619 } 3620 } 3621 } 3622 3623 methods = new_class->GetVirtualMethods(); 3624 if (methods != nullptr) { 3625 for (int index = 0; index < methods->GetLength(); index ++) { 3626 if (methods->Get(index)->GetDeclaringClass() == temp_class) { 3627 methods->Get(index)->SetDeclaringClass(new_class); 3628 } 3629 } 3630 } 3631} 3632 3633bool ClassLinker::LinkClass(Thread* self, const char* descriptor, Handle<mirror::Class> klass, 3634 Handle<mirror::ObjectArray<mirror::Class>> interfaces, 3635 mirror::Class** new_class) { 3636 CHECK_EQ(mirror::Class::kStatusLoaded, klass->GetStatus()); 3637 3638 if (!LinkSuperClass(klass)) { 3639 return false; 3640 } 3641 StackHandleScope<mirror::Class::kImtSize> imt_handle_scope( 3642 self, Runtime::Current()->GetImtUnimplementedMethod()); 3643 if (!LinkMethods(self, klass, interfaces, &imt_handle_scope)) { 3644 return false; 3645 } 3646 if (!LinkInstanceFields(self, klass)) { 3647 return false; 3648 } 3649 size_t class_size; 3650 if (!LinkStaticFields(self, klass, &class_size)) { 3651 return false; 3652 } 3653 CreateReferenceInstanceOffsets(klass); 3654 CHECK_EQ(mirror::Class::kStatusLoaded, klass->GetStatus()); 3655 3656 if (!klass->IsTemp() || (!init_done_ && klass->GetClassSize() == class_size)) { 3657 // We don't need to retire this class as it has no embedded tables or it was created the 3658 // correct size during class linker initialization. 3659 CHECK_EQ(klass->GetClassSize(), class_size) << PrettyDescriptor(klass.Get()); 3660 3661 if (klass->ShouldHaveEmbeddedImtAndVTable()) { 3662 klass->PopulateEmbeddedImtAndVTable(&imt_handle_scope); 3663 } 3664 3665 // This will notify waiters on klass that saw the not yet resolved 3666 // class in the class_table_ during EnsureResolved. 3667 mirror::Class::SetStatus(klass, mirror::Class::kStatusResolved, self); 3668 *new_class = klass.Get(); 3669 } else { 3670 CHECK(!klass->IsResolved()); 3671 // Retire the temporary class and create the correctly sized resolved class. 3672 *new_class = klass->CopyOf(self, class_size, &imt_handle_scope); 3673 if (UNLIKELY(*new_class == nullptr)) { 3674 CHECK(self->IsExceptionPending()); // Expect an OOME. 3675 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3676 return false; 3677 } 3678 3679 CHECK_EQ((*new_class)->GetClassSize(), class_size); 3680 StackHandleScope<1> hs(self); 3681 auto new_class_h = hs.NewHandleWrapper<mirror::Class>(new_class); 3682 ObjectLock<mirror::Class> lock(self, new_class_h); 3683 3684 FixupTemporaryDeclaringClass(klass.Get(), new_class_h.Get()); 3685 3686 mirror::Class* existing = UpdateClass(descriptor, new_class_h.Get(), 3687 ComputeModifiedUtf8Hash(descriptor)); 3688 CHECK(existing == nullptr || existing == klass.Get()); 3689 3690 // This will notify waiters on temp class that saw the not yet resolved class in the 3691 // class_table_ during EnsureResolved. 3692 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetired, self); 3693 3694 CHECK_EQ(new_class_h->GetStatus(), mirror::Class::kStatusResolving); 3695 // This will notify waiters on new_class that saw the not yet resolved 3696 // class in the class_table_ during EnsureResolved. 3697 mirror::Class::SetStatus(new_class_h, mirror::Class::kStatusResolved, self); 3698 } 3699 return true; 3700} 3701 3702static void CountMethodsAndFields(ClassDataItemIterator& dex_data, 3703 size_t* virtual_methods, 3704 size_t* direct_methods, 3705 size_t* static_fields, 3706 size_t* instance_fields) { 3707 *virtual_methods = *direct_methods = *static_fields = *instance_fields = 0; 3708 3709 while (dex_data.HasNextStaticField()) { 3710 dex_data.Next(); 3711 (*static_fields)++; 3712 } 3713 while (dex_data.HasNextInstanceField()) { 3714 dex_data.Next(); 3715 (*instance_fields)++; 3716 } 3717 while (dex_data.HasNextDirectMethod()) { 3718 (*direct_methods)++; 3719 dex_data.Next(); 3720 } 3721 while (dex_data.HasNextVirtualMethod()) { 3722 (*virtual_methods)++; 3723 dex_data.Next(); 3724 } 3725 DCHECK(!dex_data.HasNext()); 3726} 3727 3728static void DumpClass(std::ostream& os, 3729 const DexFile& dex_file, const DexFile::ClassDef& dex_class_def, 3730 const char* suffix) { 3731 ClassDataItemIterator dex_data(dex_file, dex_file.GetClassData(dex_class_def)); 3732 os << dex_file.GetClassDescriptor(dex_class_def) << suffix << ":\n"; 3733 os << " Static fields:\n"; 3734 while (dex_data.HasNextStaticField()) { 3735 const DexFile::FieldId& id = dex_file.GetFieldId(dex_data.GetMemberIndex()); 3736 os << " " << dex_file.GetFieldTypeDescriptor(id) << " " << dex_file.GetFieldName(id) << "\n"; 3737 dex_data.Next(); 3738 } 3739 os << " Instance fields:\n"; 3740 while (dex_data.HasNextInstanceField()) { 3741 const DexFile::FieldId& id = dex_file.GetFieldId(dex_data.GetMemberIndex()); 3742 os << " " << dex_file.GetFieldTypeDescriptor(id) << " " << dex_file.GetFieldName(id) << "\n"; 3743 dex_data.Next(); 3744 } 3745 os << " Direct methods:\n"; 3746 while (dex_data.HasNextDirectMethod()) { 3747 const DexFile::MethodId& id = dex_file.GetMethodId(dex_data.GetMemberIndex()); 3748 os << " " << dex_file.GetMethodName(id) << dex_file.GetMethodSignature(id).ToString() << "\n"; 3749 dex_data.Next(); 3750 } 3751 os << " Virtual methods:\n"; 3752 while (dex_data.HasNextVirtualMethod()) { 3753 const DexFile::MethodId& id = dex_file.GetMethodId(dex_data.GetMemberIndex()); 3754 os << " " << dex_file.GetMethodName(id) << dex_file.GetMethodSignature(id).ToString() << "\n"; 3755 dex_data.Next(); 3756 } 3757} 3758 3759static std::string DumpClasses(const DexFile& dex_file1, const DexFile::ClassDef& dex_class_def1, 3760 const DexFile& dex_file2, const DexFile::ClassDef& dex_class_def2) { 3761 std::ostringstream os; 3762 DumpClass(os, dex_file1, dex_class_def1, " (Compile time)"); 3763 DumpClass(os, dex_file2, dex_class_def2, " (Runtime)"); 3764 return os.str(); 3765} 3766 3767 3768// Very simple structural check on whether the classes match. Only compares the number of 3769// methods and fields. 3770static bool SimpleStructuralCheck(const DexFile& dex_file1, const DexFile::ClassDef& dex_class_def1, 3771 const DexFile& dex_file2, const DexFile::ClassDef& dex_class_def2, 3772 std::string* error_msg) { 3773 ClassDataItemIterator dex_data1(dex_file1, dex_file1.GetClassData(dex_class_def1)); 3774 ClassDataItemIterator dex_data2(dex_file2, dex_file2.GetClassData(dex_class_def2)); 3775 3776 // Counters for current dex file. 3777 size_t dex_virtual_methods1, dex_direct_methods1, dex_static_fields1, dex_instance_fields1; 3778 CountMethodsAndFields(dex_data1, &dex_virtual_methods1, &dex_direct_methods1, &dex_static_fields1, 3779 &dex_instance_fields1); 3780 // Counters for compile-time dex file. 3781 size_t dex_virtual_methods2, dex_direct_methods2, dex_static_fields2, dex_instance_fields2; 3782 CountMethodsAndFields(dex_data2, &dex_virtual_methods2, &dex_direct_methods2, &dex_static_fields2, 3783 &dex_instance_fields2); 3784 3785 if (dex_virtual_methods1 != dex_virtual_methods2) { 3786 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 3787 *error_msg = StringPrintf("Virtual method count off: %zu vs %zu\n%s", dex_virtual_methods1, 3788 dex_virtual_methods2, class_dump.c_str()); 3789 return false; 3790 } 3791 if (dex_direct_methods1 != dex_direct_methods2) { 3792 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 3793 *error_msg = StringPrintf("Direct method count off: %zu vs %zu\n%s", dex_direct_methods1, 3794 dex_direct_methods2, class_dump.c_str()); 3795 return false; 3796 } 3797 if (dex_static_fields1 != dex_static_fields2) { 3798 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 3799 *error_msg = StringPrintf("Static field count off: %zu vs %zu\n%s", dex_static_fields1, 3800 dex_static_fields2, class_dump.c_str()); 3801 return false; 3802 } 3803 if (dex_instance_fields1 != dex_instance_fields2) { 3804 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 3805 *error_msg = StringPrintf("Instance field count off: %zu vs %zu\n%s", dex_instance_fields1, 3806 dex_instance_fields2, class_dump.c_str()); 3807 return false; 3808 } 3809 3810 return true; 3811} 3812 3813// Checks whether a the super-class changed from what we had at compile-time. This would 3814// invalidate quickening. 3815static bool CheckSuperClassChange(Handle<mirror::Class> klass, 3816 const DexFile& dex_file, 3817 const DexFile::ClassDef& class_def, 3818 mirror::Class* super_class) 3819 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3820 // Check for unexpected changes in the superclass. 3821 // Quick check 1) is the super_class class-loader the boot class loader? This always has 3822 // precedence. 3823 if (super_class->GetClassLoader() != nullptr && 3824 // Quick check 2) different dex cache? Breaks can only occur for different dex files, 3825 // which is implied by different dex cache. 3826 klass->GetDexCache() != super_class->GetDexCache()) { 3827 // Now comes the expensive part: things can be broken if (a) the klass' dex file has a 3828 // definition for the super-class, and (b) the files are in separate oat files. The oat files 3829 // are referenced from the dex file, so do (b) first. Only relevant if we have oat files. 3830 const OatFile* class_oat_file = dex_file.GetOatFile(); 3831 if (class_oat_file != nullptr) { 3832 const OatFile* loaded_super_oat_file = super_class->GetDexFile().GetOatFile(); 3833 if (loaded_super_oat_file != nullptr && class_oat_file != loaded_super_oat_file) { 3834 // Now check (a). 3835 const DexFile::ClassDef* super_class_def = dex_file.FindClassDef(class_def.superclass_idx_); 3836 if (super_class_def != nullptr) { 3837 // Uh-oh, we found something. Do our check. 3838 std::string error_msg; 3839 if (!SimpleStructuralCheck(dex_file, *super_class_def, 3840 super_class->GetDexFile(), *super_class->GetClassDef(), 3841 &error_msg)) { 3842 // Print a warning to the log. This exception might be caught, e.g., as common in test 3843 // drivers. When the class is later tried to be used, we re-throw a new instance, as we 3844 // only save the type of the exception. 3845 LOG(WARNING) << "Incompatible structural change detected: " << 3846 StringPrintf( 3847 "Structural change of %s is hazardous (%s at compile time, %s at runtime): %s", 3848 PrettyType(super_class_def->class_idx_, dex_file).c_str(), 3849 class_oat_file->GetLocation().c_str(), 3850 loaded_super_oat_file->GetLocation().c_str(), 3851 error_msg.c_str()); 3852 ThrowIncompatibleClassChangeError(klass.Get(), 3853 "Structural change of %s is hazardous (%s at compile time, %s at runtime): %s", 3854 PrettyType(super_class_def->class_idx_, dex_file).c_str(), 3855 class_oat_file->GetLocation().c_str(), 3856 loaded_super_oat_file->GetLocation().c_str(), 3857 error_msg.c_str()); 3858 return false; 3859 } 3860 } 3861 } 3862 } 3863 } 3864 return true; 3865} 3866 3867bool ClassLinker::LoadSuperAndInterfaces(Handle<mirror::Class> klass, const DexFile& dex_file) { 3868 CHECK_EQ(mirror::Class::kStatusIdx, klass->GetStatus()); 3869 const DexFile::ClassDef& class_def = dex_file.GetClassDef(klass->GetDexClassDefIndex()); 3870 uint16_t super_class_idx = class_def.superclass_idx_; 3871 if (super_class_idx != DexFile::kDexNoIndex16) { 3872 mirror::Class* super_class = ResolveType(dex_file, super_class_idx, klass.Get()); 3873 if (super_class == nullptr) { 3874 DCHECK(Thread::Current()->IsExceptionPending()); 3875 return false; 3876 } 3877 // Verify 3878 if (!klass->CanAccess(super_class)) { 3879 ThrowIllegalAccessError(klass.Get(), "Class %s extended by class %s is inaccessible", 3880 PrettyDescriptor(super_class).c_str(), 3881 PrettyDescriptor(klass.Get()).c_str()); 3882 return false; 3883 } 3884 CHECK(super_class->IsResolved()); 3885 klass->SetSuperClass(super_class); 3886 3887 if (!CheckSuperClassChange(klass, dex_file, class_def, super_class)) { 3888 DCHECK(Thread::Current()->IsExceptionPending()); 3889 return false; 3890 } 3891 } 3892 const DexFile::TypeList* interfaces = dex_file.GetInterfacesList(class_def); 3893 if (interfaces != nullptr) { 3894 for (size_t i = 0; i < interfaces->Size(); i++) { 3895 uint16_t idx = interfaces->GetTypeItem(i).type_idx_; 3896 mirror::Class* interface = ResolveType(dex_file, idx, klass.Get()); 3897 if (interface == nullptr) { 3898 DCHECK(Thread::Current()->IsExceptionPending()); 3899 return false; 3900 } 3901 // Verify 3902 if (!klass->CanAccess(interface)) { 3903 // TODO: the RI seemed to ignore this in my testing. 3904 ThrowIllegalAccessError(klass.Get(), "Interface %s implemented by class %s is inaccessible", 3905 PrettyDescriptor(interface).c_str(), 3906 PrettyDescriptor(klass.Get()).c_str()); 3907 return false; 3908 } 3909 } 3910 } 3911 // Mark the class as loaded. 3912 mirror::Class::SetStatus(klass, mirror::Class::kStatusLoaded, nullptr); 3913 return true; 3914} 3915 3916bool ClassLinker::LinkSuperClass(Handle<mirror::Class> klass) { 3917 CHECK(!klass->IsPrimitive()); 3918 mirror::Class* super = klass->GetSuperClass(); 3919 if (klass.Get() == GetClassRoot(kJavaLangObject)) { 3920 if (super != nullptr) { 3921 ThrowClassFormatError(klass.Get(), "java.lang.Object must not have a superclass"); 3922 return false; 3923 } 3924 return true; 3925 } 3926 if (super == nullptr) { 3927 ThrowLinkageError(klass.Get(), "No superclass defined for class %s", 3928 PrettyDescriptor(klass.Get()).c_str()); 3929 return false; 3930 } 3931 // Verify 3932 if (super->IsFinal() || super->IsInterface()) { 3933 ThrowIncompatibleClassChangeError(klass.Get(), "Superclass %s of %s is %s", 3934 PrettyDescriptor(super).c_str(), 3935 PrettyDescriptor(klass.Get()).c_str(), 3936 super->IsFinal() ? "declared final" : "an interface"); 3937 return false; 3938 } 3939 if (!klass->CanAccess(super)) { 3940 ThrowIllegalAccessError(klass.Get(), "Superclass %s is inaccessible to class %s", 3941 PrettyDescriptor(super).c_str(), 3942 PrettyDescriptor(klass.Get()).c_str()); 3943 return false; 3944 } 3945 3946 // Inherit kAccClassIsFinalizable from the superclass in case this 3947 // class doesn't override finalize. 3948 if (super->IsFinalizable()) { 3949 klass->SetFinalizable(); 3950 } 3951 3952 // Inherit reference flags (if any) from the superclass. 3953 int reference_flags = (super->GetAccessFlags() & kAccReferenceFlagsMask); 3954 if (reference_flags != 0) { 3955 klass->SetAccessFlags(klass->GetAccessFlags() | reference_flags); 3956 } 3957 // Disallow custom direct subclasses of java.lang.ref.Reference. 3958 if (init_done_ && super == GetClassRoot(kJavaLangRefReference)) { 3959 ThrowLinkageError(klass.Get(), 3960 "Class %s attempts to subclass java.lang.ref.Reference, which is not allowed", 3961 PrettyDescriptor(klass.Get()).c_str()); 3962 return false; 3963 } 3964 3965 if (kIsDebugBuild) { 3966 // Ensure super classes are fully resolved prior to resolving fields.. 3967 while (super != nullptr) { 3968 CHECK(super->IsResolved()); 3969 super = super->GetSuperClass(); 3970 } 3971 } 3972 return true; 3973} 3974 3975// Populate the class vtable and itable. Compute return type indices. 3976bool ClassLinker::LinkMethods(Thread* self, Handle<mirror::Class> klass, 3977 Handle<mirror::ObjectArray<mirror::Class>> interfaces, 3978 StackHandleScope<mirror::Class::kImtSize>* out_imt) { 3979 self->AllowThreadSuspension(); 3980 if (klass->IsInterface()) { 3981 // No vtable. 3982 size_t count = klass->NumVirtualMethods(); 3983 if (!IsUint<16>(count)) { 3984 ThrowClassFormatError(klass.Get(), "Too many methods on interface: %zd", count); 3985 return false; 3986 } 3987 for (size_t i = 0; i < count; ++i) { 3988 klass->GetVirtualMethodDuringLinking(i)->SetMethodIndex(i); 3989 } 3990 } else if (!LinkVirtualMethods(self, klass)) { // Link virtual methods first. 3991 return false; 3992 } 3993 return LinkInterfaceMethods(self, klass, interfaces, out_imt); // Link interface method last. 3994} 3995 3996// Comparator for name and signature of a method, used in finding overriding methods. Implementation 3997// avoids the use of handles, if it didn't then rather than compare dex files we could compare dex 3998// caches in the implementation below. 3999class MethodNameAndSignatureComparator FINAL : public ValueObject { 4000 public: 4001 explicit MethodNameAndSignatureComparator(mirror::ArtMethod* method) 4002 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) : 4003 dex_file_(method->GetDexFile()), mid_(&dex_file_->GetMethodId(method->GetDexMethodIndex())), 4004 name_(nullptr), name_len_(0) { 4005 DCHECK(!method->IsProxyMethod()) << PrettyMethod(method); 4006 } 4007 4008 const char* GetName() { 4009 if (name_ == nullptr) { 4010 name_ = dex_file_->StringDataAndUtf16LengthByIdx(mid_->name_idx_, &name_len_); 4011 } 4012 return name_; 4013 } 4014 4015 bool HasSameNameAndSignature(mirror::ArtMethod* other) 4016 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4017 DCHECK(!other->IsProxyMethod()) << PrettyMethod(other); 4018 const DexFile* other_dex_file = other->GetDexFile(); 4019 const DexFile::MethodId& other_mid = other_dex_file->GetMethodId(other->GetDexMethodIndex()); 4020 if (dex_file_ == other_dex_file) { 4021 return mid_->name_idx_ == other_mid.name_idx_ && mid_->proto_idx_ == other_mid.proto_idx_; 4022 } 4023 GetName(); // Only used to make sure its calculated. 4024 uint32_t other_name_len; 4025 const char* other_name = other_dex_file->StringDataAndUtf16LengthByIdx(other_mid.name_idx_, 4026 &other_name_len); 4027 if (name_len_ != other_name_len || strcmp(name_, other_name) != 0) { 4028 return false; 4029 } 4030 return dex_file_->GetMethodSignature(*mid_) == other_dex_file->GetMethodSignature(other_mid); 4031 } 4032 4033 private: 4034 // Dex file for the method to compare against. 4035 const DexFile* const dex_file_; 4036 // MethodId for the method to compare against. 4037 const DexFile::MethodId* const mid_; 4038 // Lazily computed name from the dex file's strings. 4039 const char* name_; 4040 // Lazily computed name length. 4041 uint32_t name_len_; 4042}; 4043 4044class LinkVirtualHashTable { 4045 public: 4046 LinkVirtualHashTable(Handle<mirror::Class> klass, size_t hash_size, uint32_t* hash_table) 4047 : klass_(klass), hash_size_(hash_size), hash_table_(hash_table) { 4048 std::fill(hash_table_, hash_table_ + hash_size_, invalid_index_); 4049 } 4050 void Add(uint32_t virtual_method_index) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4051 mirror::ArtMethod* local_method = klass_->GetVirtualMethodDuringLinking(virtual_method_index); 4052 const char* name = local_method->GetName(); 4053 uint32_t hash = ComputeModifiedUtf8Hash(name); 4054 uint32_t index = hash % hash_size_; 4055 // Linear probe until we have an empty slot. 4056 while (hash_table_[index] != invalid_index_) { 4057 if (++index == hash_size_) { 4058 index = 0; 4059 } 4060 } 4061 hash_table_[index] = virtual_method_index; 4062 } 4063 uint32_t FindAndRemove(MethodNameAndSignatureComparator* comparator) 4064 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4065 const char* name = comparator->GetName(); 4066 uint32_t hash = ComputeModifiedUtf8Hash(name); 4067 size_t index = hash % hash_size_; 4068 while (true) { 4069 const uint32_t value = hash_table_[index]; 4070 // Since linear probe makes continuous blocks, hitting an invalid index means we are done 4071 // the block and can safely assume not found. 4072 if (value == invalid_index_) { 4073 break; 4074 } 4075 if (value != removed_index_) { // This signifies not already overriden. 4076 mirror::ArtMethod* virtual_method = 4077 klass_->GetVirtualMethodDuringLinking(value); 4078 if (comparator->HasSameNameAndSignature(virtual_method->GetInterfaceMethodIfProxy())) { 4079 hash_table_[index] = removed_index_; 4080 return value; 4081 } 4082 } 4083 if (++index == hash_size_) { 4084 index = 0; 4085 } 4086 } 4087 return GetNotFoundIndex(); 4088 } 4089 static uint32_t GetNotFoundIndex() { 4090 return invalid_index_; 4091 } 4092 4093 private: 4094 static const uint32_t invalid_index_; 4095 static const uint32_t removed_index_; 4096 4097 Handle<mirror::Class> klass_; 4098 const size_t hash_size_; 4099 uint32_t* const hash_table_; 4100}; 4101 4102const uint32_t LinkVirtualHashTable::invalid_index_ = std::numeric_limits<uint32_t>::max(); 4103const uint32_t LinkVirtualHashTable::removed_index_ = std::numeric_limits<uint32_t>::max() - 1; 4104 4105bool ClassLinker::LinkVirtualMethods(Thread* self, Handle<mirror::Class> klass) { 4106 const size_t num_virtual_methods = klass->NumVirtualMethods(); 4107 if (klass->HasSuperClass()) { 4108 const size_t super_vtable_length = klass->GetSuperClass()->GetVTableLength(); 4109 const size_t max_count = num_virtual_methods + super_vtable_length; 4110 StackHandleScope<2> hs(self); 4111 Handle<mirror::Class> super_class(hs.NewHandle(klass->GetSuperClass())); 4112 MutableHandle<mirror::ObjectArray<mirror::ArtMethod>> vtable; 4113 if (super_class->ShouldHaveEmbeddedImtAndVTable()) { 4114 vtable = hs.NewHandle(AllocArtMethodArray(self, max_count)); 4115 if (UNLIKELY(vtable.Get() == nullptr)) { 4116 CHECK(self->IsExceptionPending()); // OOME. 4117 return false; 4118 } 4119 for (size_t i = 0; i < super_vtable_length; i++) { 4120 vtable->SetWithoutChecks<false>(i, super_class->GetEmbeddedVTableEntry(i)); 4121 } 4122 if (num_virtual_methods == 0) { 4123 klass->SetVTable(vtable.Get()); 4124 return true; 4125 } 4126 } else { 4127 mirror::ObjectArray<mirror::ArtMethod>* super_vtable = super_class->GetVTable(); 4128 CHECK(super_vtable != nullptr) << PrettyClass(super_class.Get()); 4129 if (num_virtual_methods == 0) { 4130 klass->SetVTable(super_vtable); 4131 return true; 4132 } 4133 vtable = hs.NewHandle(super_vtable->CopyOf(self, max_count)); 4134 if (UNLIKELY(vtable.Get() == nullptr)) { 4135 CHECK(self->IsExceptionPending()); // OOME. 4136 return false; 4137 } 4138 } 4139 // How the algorithm works: 4140 // 1. Populate hash table by adding num_virtual_methods from klass. The values in the hash 4141 // table are: invalid_index for unused slots, index super_vtable_length + i for a virtual 4142 // method which has not been matched to a vtable method, and j if the virtual method at the 4143 // index overrode the super virtual method at index j. 4144 // 2. Loop through super virtual methods, if they overwrite, update hash table to j 4145 // (j < super_vtable_length) to avoid redundant checks. (TODO maybe use this info for reducing 4146 // the need for the initial vtable which we later shrink back down). 4147 // 3. Add non overridden methods to the end of the vtable. 4148 static constexpr size_t kMaxStackHash = 250; 4149 const size_t hash_table_size = num_virtual_methods * 3; 4150 uint32_t* hash_table_ptr; 4151 std::unique_ptr<uint32_t[]> hash_heap_storage; 4152 if (hash_table_size <= kMaxStackHash) { 4153 hash_table_ptr = reinterpret_cast<uint32_t*>( 4154 alloca(hash_table_size * sizeof(*hash_table_ptr))); 4155 } else { 4156 hash_heap_storage.reset(new uint32_t[hash_table_size]); 4157 hash_table_ptr = hash_heap_storage.get(); 4158 } 4159 LinkVirtualHashTable hash_table(klass, hash_table_size, hash_table_ptr); 4160 // Add virtual methods to the hash table. 4161 for (size_t i = 0; i < num_virtual_methods; ++i) { 4162 hash_table.Add(i); 4163 } 4164 // Loop through each super vtable method and see if they are overriden by a method we added to 4165 // the hash table. 4166 for (size_t j = 0; j < super_vtable_length; ++j) { 4167 // Search the hash table to see if we are overidden by any method. 4168 mirror::ArtMethod* super_method = vtable->GetWithoutChecks(j); 4169 MethodNameAndSignatureComparator super_method_name_comparator( 4170 super_method->GetInterfaceMethodIfProxy()); 4171 uint32_t hash_index = hash_table.FindAndRemove(&super_method_name_comparator); 4172 if (hash_index != hash_table.GetNotFoundIndex()) { 4173 mirror::ArtMethod* virtual_method = klass->GetVirtualMethodDuringLinking(hash_index); 4174 if (klass->CanAccessMember(super_method->GetDeclaringClass(), 4175 super_method->GetAccessFlags())) { 4176 if (super_method->IsFinal()) { 4177 ThrowLinkageError(klass.Get(), "Method %s overrides final method in class %s", 4178 PrettyMethod(virtual_method).c_str(), 4179 super_method->GetDeclaringClassDescriptor()); 4180 return false; 4181 } 4182 vtable->SetWithoutChecks<false>(j, virtual_method); 4183 virtual_method->SetMethodIndex(j); 4184 } else { 4185 LOG(WARNING) << "Before Android 4.1, method " << PrettyMethod(virtual_method) 4186 << " would have incorrectly overridden the package-private method in " 4187 << PrettyDescriptor(super_method->GetDeclaringClassDescriptor()); 4188 } 4189 } 4190 } 4191 // Add the non overridden methods at the end. 4192 size_t actual_count = super_vtable_length; 4193 for (size_t i = 0; i < num_virtual_methods; ++i) { 4194 mirror::ArtMethod* local_method = klass->GetVirtualMethodDuringLinking(i); 4195 size_t method_idx = local_method->GetMethodIndexDuringLinking(); 4196 if (method_idx < super_vtable_length && 4197 local_method == vtable->GetWithoutChecks(method_idx)) { 4198 continue; 4199 } 4200 vtable->SetWithoutChecks<false>(actual_count, local_method); 4201 local_method->SetMethodIndex(actual_count); 4202 ++actual_count; 4203 } 4204 if (!IsUint<16>(actual_count)) { 4205 ThrowClassFormatError(klass.Get(), "Too many methods defined on class: %zd", actual_count); 4206 return false; 4207 } 4208 // Shrink vtable if possible 4209 CHECK_LE(actual_count, max_count); 4210 if (actual_count < max_count) { 4211 vtable.Assign(vtable->CopyOf(self, actual_count)); 4212 if (UNLIKELY(vtable.Get() == nullptr)) { 4213 CHECK(self->IsExceptionPending()); // OOME. 4214 return false; 4215 } 4216 } 4217 klass->SetVTable(vtable.Get()); 4218 } else { 4219 CHECK_EQ(klass.Get(), GetClassRoot(kJavaLangObject)); 4220 if (!IsUint<16>(num_virtual_methods)) { 4221 ThrowClassFormatError(klass.Get(), "Too many methods: %d", 4222 static_cast<int>(num_virtual_methods)); 4223 return false; 4224 } 4225 mirror::ObjectArray<mirror::ArtMethod>* vtable = AllocArtMethodArray(self, num_virtual_methods); 4226 if (UNLIKELY(vtable == nullptr)) { 4227 CHECK(self->IsExceptionPending()); // OOME. 4228 return false; 4229 } 4230 for (size_t i = 0; i < num_virtual_methods; ++i) { 4231 mirror::ArtMethod* virtual_method = klass->GetVirtualMethodDuringLinking(i); 4232 vtable->SetWithoutChecks<false>(i, virtual_method); 4233 virtual_method->SetMethodIndex(i & 0xFFFF); 4234 } 4235 klass->SetVTable(vtable); 4236 } 4237 return true; 4238} 4239 4240bool ClassLinker::LinkInterfaceMethods(Thread* self, Handle<mirror::Class> klass, 4241 Handle<mirror::ObjectArray<mirror::Class>> interfaces, 4242 StackHandleScope<mirror::Class::kImtSize>* out_imt) { 4243 StackHandleScope<3> hs(self); 4244 Runtime* const runtime = Runtime::Current(); 4245 const bool has_superclass = klass->HasSuperClass(); 4246 const size_t super_ifcount = has_superclass ? klass->GetSuperClass()->GetIfTableCount() : 0U; 4247 const bool have_interfaces = interfaces.Get() != nullptr; 4248 const size_t num_interfaces = 4249 have_interfaces ? interfaces->GetLength() : klass->NumDirectInterfaces(); 4250 if (num_interfaces == 0) { 4251 if (super_ifcount == 0) { 4252 // Class implements no interfaces. 4253 DCHECK_EQ(klass->GetIfTableCount(), 0); 4254 DCHECK(klass->GetIfTable() == nullptr); 4255 return true; 4256 } 4257 // Class implements same interfaces as parent, are any of these not marker interfaces? 4258 bool has_non_marker_interface = false; 4259 mirror::IfTable* super_iftable = klass->GetSuperClass()->GetIfTable(); 4260 for (size_t i = 0; i < super_ifcount; ++i) { 4261 if (super_iftable->GetMethodArrayCount(i) > 0) { 4262 has_non_marker_interface = true; 4263 break; 4264 } 4265 } 4266 // Class just inherits marker interfaces from parent so recycle parent's iftable. 4267 if (!has_non_marker_interface) { 4268 klass->SetIfTable(super_iftable); 4269 return true; 4270 } 4271 } 4272 size_t ifcount = super_ifcount + num_interfaces; 4273 for (size_t i = 0; i < num_interfaces; i++) { 4274 mirror::Class* interface = have_interfaces ? 4275 interfaces->GetWithoutChecks(i) : mirror::Class::GetDirectInterface(self, klass, i); 4276 DCHECK(interface != nullptr); 4277 if (UNLIKELY(!interface->IsInterface())) { 4278 std::string temp; 4279 ThrowIncompatibleClassChangeError(klass.Get(), "Class %s implements non-interface class %s", 4280 PrettyDescriptor(klass.Get()).c_str(), 4281 PrettyDescriptor(interface->GetDescriptor(&temp)).c_str()); 4282 return false; 4283 } 4284 ifcount += interface->GetIfTableCount(); 4285 } 4286 MutableHandle<mirror::IfTable> iftable(hs.NewHandle(AllocIfTable(self, ifcount))); 4287 if (UNLIKELY(iftable.Get() == nullptr)) { 4288 CHECK(self->IsExceptionPending()); // OOME. 4289 return false; 4290 } 4291 if (super_ifcount != 0) { 4292 mirror::IfTable* super_iftable = klass->GetSuperClass()->GetIfTable(); 4293 for (size_t i = 0; i < super_ifcount; i++) { 4294 mirror::Class* super_interface = super_iftable->GetInterface(i); 4295 iftable->SetInterface(i, super_interface); 4296 } 4297 } 4298 self->AllowThreadSuspension(); 4299 // Flatten the interface inheritance hierarchy. 4300 size_t idx = super_ifcount; 4301 for (size_t i = 0; i < num_interfaces; i++) { 4302 mirror::Class* interface = have_interfaces ? interfaces->Get(i) : 4303 mirror::Class::GetDirectInterface(self, klass, i); 4304 // Check if interface is already in iftable 4305 bool duplicate = false; 4306 for (size_t j = 0; j < idx; j++) { 4307 mirror::Class* existing_interface = iftable->GetInterface(j); 4308 if (existing_interface == interface) { 4309 duplicate = true; 4310 break; 4311 } 4312 } 4313 if (!duplicate) { 4314 // Add this non-duplicate interface. 4315 iftable->SetInterface(idx++, interface); 4316 // Add this interface's non-duplicate super-interfaces. 4317 for (int32_t j = 0; j < interface->GetIfTableCount(); j++) { 4318 mirror::Class* super_interface = interface->GetIfTable()->GetInterface(j); 4319 bool super_duplicate = false; 4320 for (size_t k = 0; k < idx; k++) { 4321 mirror::Class* existing_interface = iftable->GetInterface(k); 4322 if (existing_interface == super_interface) { 4323 super_duplicate = true; 4324 break; 4325 } 4326 } 4327 if (!super_duplicate) { 4328 iftable->SetInterface(idx++, super_interface); 4329 } 4330 } 4331 } 4332 } 4333 self->AllowThreadSuspension(); 4334 // Shrink iftable in case duplicates were found 4335 if (idx < ifcount) { 4336 DCHECK_NE(num_interfaces, 0U); 4337 iftable.Assign(down_cast<mirror::IfTable*>(iftable->CopyOf(self, idx * mirror::IfTable::kMax))); 4338 if (UNLIKELY(iftable.Get() == nullptr)) { 4339 CHECK(self->IsExceptionPending()); // OOME. 4340 return false; 4341 } 4342 ifcount = idx; 4343 } else { 4344 DCHECK_EQ(idx, ifcount); 4345 } 4346 klass->SetIfTable(iftable.Get()); 4347 // If we're an interface, we don't need the vtable pointers, so we're done. 4348 if (klass->IsInterface()) { 4349 return true; 4350 } 4351 size_t miranda_list_size = 0; 4352 size_t max_miranda_methods = 0; // The max size of miranda_list. 4353 for (size_t i = 0; i < ifcount; ++i) { 4354 max_miranda_methods += iftable->GetInterface(i)->NumVirtualMethods(); 4355 } 4356 MutableHandle<mirror::ObjectArray<mirror::ArtMethod>> 4357 miranda_list(hs.NewHandle(AllocArtMethodArray(self, max_miranda_methods))); 4358 MutableHandle<mirror::ObjectArray<mirror::ArtMethod>> vtable( 4359 hs.NewHandle(klass->GetVTableDuringLinking())); 4360 // Copy the IMT from the super class if possible. 4361 bool extend_super_iftable = false; 4362 if (has_superclass) { 4363 mirror::Class* super_class = klass->GetSuperClass(); 4364 extend_super_iftable = true; 4365 if (super_class->ShouldHaveEmbeddedImtAndVTable()) { 4366 for (size_t i = 0; i < mirror::Class::kImtSize; ++i) { 4367 out_imt->SetReference(i, super_class->GetEmbeddedImTableEntry(i)); 4368 } 4369 } else { 4370 // No imt in the super class, need to reconstruct from the iftable. 4371 mirror::IfTable* if_table = super_class->GetIfTable(); 4372 mirror::ArtMethod* conflict_method = runtime->GetImtConflictMethod(); 4373 const size_t length = super_class->GetIfTableCount(); 4374 for (size_t i = 0; i < length; ++i) { 4375 mirror::Class* interface = iftable->GetInterface(i); 4376 const size_t num_virtuals = interface->NumVirtualMethods(); 4377 const size_t method_array_count = if_table->GetMethodArrayCount(i); 4378 DCHECK_EQ(num_virtuals, method_array_count); 4379 if (method_array_count == 0) { 4380 continue; 4381 } 4382 mirror::ObjectArray<mirror::ArtMethod>* method_array = if_table->GetMethodArray(i); 4383 for (size_t j = 0; j < num_virtuals; ++j) { 4384 mirror::ArtMethod* method = method_array->GetWithoutChecks(j); 4385 if (method->IsMiranda()) { 4386 continue; 4387 } 4388 mirror::ArtMethod* interface_method = interface->GetVirtualMethod(j); 4389 uint32_t imt_index = interface_method->GetDexMethodIndex() % mirror::Class::kImtSize; 4390 mirror::ArtMethod* imt_ref = out_imt->GetReference(imt_index)->AsArtMethod(); 4391 if (imt_ref == runtime->GetImtUnimplementedMethod()) { 4392 out_imt->SetReference(imt_index, method); 4393 } else if (imt_ref != conflict_method) { 4394 out_imt->SetReference(imt_index, conflict_method); 4395 } 4396 } 4397 } 4398 } 4399 } 4400 for (size_t i = 0; i < ifcount; ++i) { 4401 self->AllowThreadSuspension(); 4402 size_t num_methods = iftable->GetInterface(i)->NumVirtualMethods(); 4403 if (num_methods > 0) { 4404 StackHandleScope<2> hs2(self); 4405 const bool is_super = i < super_ifcount; 4406 const bool super_interface = is_super && extend_super_iftable; 4407 Handle<mirror::ObjectArray<mirror::ArtMethod>> method_array; 4408 Handle<mirror::ObjectArray<mirror::ArtMethod>> input_array; 4409 if (super_interface) { 4410 mirror::IfTable* if_table = klass->GetSuperClass()->GetIfTable(); 4411 DCHECK(if_table != nullptr); 4412 DCHECK(if_table->GetMethodArray(i) != nullptr); 4413 // If we are working on a super interface, try extending the existing method array. 4414 method_array = hs2.NewHandle(if_table->GetMethodArray(i)->Clone(self)-> 4415 AsObjectArray<mirror::ArtMethod>()); 4416 // We are overwriting a super class interface, try to only virtual methods instead of the 4417 // whole vtable. 4418 input_array = hs2.NewHandle(klass->GetVirtualMethods()); 4419 } else { 4420 method_array = hs2.NewHandle(AllocArtMethodArray(self, num_methods)); 4421 // A new interface, we need the whole vtable incase a new interface method is implemented 4422 // in the whole superclass. 4423 input_array = vtable; 4424 } 4425 if (UNLIKELY(method_array.Get() == nullptr)) { 4426 CHECK(self->IsExceptionPending()); // OOME. 4427 return false; 4428 } 4429 iftable->SetMethodArray(i, method_array.Get()); 4430 if (input_array.Get() == nullptr) { 4431 // If the added virtual methods is empty, do nothing. 4432 DCHECK(super_interface); 4433 continue; 4434 } 4435 for (size_t j = 0; j < num_methods; ++j) { 4436 mirror::ArtMethod* interface_method = iftable->GetInterface(i)->GetVirtualMethod(j); 4437 MethodNameAndSignatureComparator interface_name_comparator( 4438 interface_method->GetInterfaceMethodIfProxy()); 4439 int32_t k; 4440 // For each method listed in the interface's method list, find the 4441 // matching method in our class's method list. We want to favor the 4442 // subclass over the superclass, which just requires walking 4443 // back from the end of the vtable. (This only matters if the 4444 // superclass defines a private method and this class redefines 4445 // it -- otherwise it would use the same vtable slot. In .dex files 4446 // those don't end up in the virtual method table, so it shouldn't 4447 // matter which direction we go. We walk it backward anyway.) 4448 for (k = input_array->GetLength() - 1; k >= 0; --k) { 4449 mirror::ArtMethod* vtable_method = input_array->GetWithoutChecks(k); 4450 mirror::ArtMethod* vtable_method_for_name_comparison = 4451 vtable_method->GetInterfaceMethodIfProxy(); 4452 if (interface_name_comparator.HasSameNameAndSignature( 4453 vtable_method_for_name_comparison)) { 4454 if (!vtable_method->IsAbstract() && !vtable_method->IsPublic()) { 4455 ThrowIllegalAccessError( 4456 klass.Get(), 4457 "Method '%s' implementing interface method '%s' is not public", 4458 PrettyMethod(vtable_method).c_str(), 4459 PrettyMethod(interface_method).c_str()); 4460 return false; 4461 } 4462 method_array->SetWithoutChecks<false>(j, vtable_method); 4463 // Place method in imt if entry is empty, place conflict otherwise. 4464 uint32_t imt_index = interface_method->GetDexMethodIndex() % mirror::Class::kImtSize; 4465 mirror::ArtMethod* imt_ref = out_imt->GetReference(imt_index)->AsArtMethod(); 4466 mirror::ArtMethod* conflict_method = runtime->GetImtConflictMethod(); 4467 if (imt_ref == runtime->GetImtUnimplementedMethod()) { 4468 out_imt->SetReference(imt_index, vtable_method); 4469 } else if (imt_ref != conflict_method) { 4470 // If we are not a conflict and we have the same signature and name as the imt entry, 4471 // it must be that we overwrote a superclass vtable entry. 4472 MethodNameAndSignatureComparator imt_ref_name_comparator( 4473 imt_ref->GetInterfaceMethodIfProxy()); 4474 if (imt_ref_name_comparator.HasSameNameAndSignature( 4475 vtable_method_for_name_comparison)) { 4476 out_imt->SetReference(imt_index, vtable_method); 4477 } else { 4478 out_imt->SetReference(imt_index, conflict_method); 4479 } 4480 } 4481 break; 4482 } 4483 } 4484 if (k < 0 && !super_interface) { 4485 mirror::ArtMethod* miranda_method = nullptr; 4486 for (size_t l = 0; l < miranda_list_size; ++l) { 4487 mirror::ArtMethod* mir_method = miranda_list->Get(l); 4488 if (interface_name_comparator.HasSameNameAndSignature(mir_method)) { 4489 miranda_method = mir_method; 4490 break; 4491 } 4492 } 4493 if (miranda_method == nullptr) { 4494 // Point the interface table at a phantom slot. 4495 miranda_method = interface_method->Clone(self)->AsArtMethod(); 4496 if (UNLIKELY(miranda_method == nullptr)) { 4497 CHECK(self->IsExceptionPending()); // OOME. 4498 return false; 4499 } 4500 DCHECK_LT(miranda_list_size, max_miranda_methods); 4501 miranda_list->Set<false>(miranda_list_size++, miranda_method); 4502 } 4503 method_array->SetWithoutChecks<false>(j, miranda_method); 4504 } 4505 } 4506 } 4507 } 4508 if (miranda_list_size > 0) { 4509 int old_method_count = klass->NumVirtualMethods(); 4510 int new_method_count = old_method_count + miranda_list_size; 4511 mirror::ObjectArray<mirror::ArtMethod>* virtuals; 4512 if (old_method_count == 0) { 4513 virtuals = AllocArtMethodArray(self, new_method_count); 4514 } else { 4515 virtuals = klass->GetVirtualMethods()->CopyOf(self, new_method_count); 4516 } 4517 if (UNLIKELY(virtuals == nullptr)) { 4518 CHECK(self->IsExceptionPending()); // OOME. 4519 return false; 4520 } 4521 klass->SetVirtualMethods(virtuals); 4522 4523 int old_vtable_count = vtable->GetLength(); 4524 int new_vtable_count = old_vtable_count + miranda_list_size; 4525 vtable.Assign(vtable->CopyOf(self, new_vtable_count)); 4526 if (UNLIKELY(vtable.Get() == nullptr)) { 4527 CHECK(self->IsExceptionPending()); // OOME. 4528 return false; 4529 } 4530 for (size_t i = 0; i < miranda_list_size; ++i) { 4531 mirror::ArtMethod* method = miranda_list->Get(i); 4532 // Leave the declaring class alone as type indices are relative to it 4533 method->SetAccessFlags(method->GetAccessFlags() | kAccMiranda); 4534 method->SetMethodIndex(0xFFFF & (old_vtable_count + i)); 4535 klass->SetVirtualMethod(old_method_count + i, method); 4536 vtable->SetWithoutChecks<false>(old_vtable_count + i, method); 4537 } 4538 // TODO: do not assign to the vtable field until it is fully constructed. 4539 klass->SetVTable(vtable.Get()); 4540 } 4541 4542 if (kIsDebugBuild) { 4543 mirror::ObjectArray<mirror::ArtMethod>* check_vtable = klass->GetVTableDuringLinking(); 4544 for (int i = 0; i < check_vtable->GetLength(); ++i) { 4545 CHECK(check_vtable->GetWithoutChecks(i) != nullptr); 4546 } 4547 } 4548 4549 self->AllowThreadSuspension(); 4550 return true; 4551} 4552 4553bool ClassLinker::LinkInstanceFields(Thread* self, Handle<mirror::Class> klass) { 4554 CHECK(klass.Get() != nullptr); 4555 return LinkFields(self, klass, false, nullptr); 4556} 4557 4558bool ClassLinker::LinkStaticFields(Thread* self, Handle<mirror::Class> klass, size_t* class_size) { 4559 CHECK(klass.Get() != nullptr); 4560 return LinkFields(self, klass, true, class_size); 4561} 4562 4563struct LinkFieldsComparator { 4564 explicit LinkFieldsComparator() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4565 } 4566 // No thread safety analysis as will be called from STL. Checked lock held in constructor. 4567 bool operator()(mirror::ArtField* field1, mirror::ArtField* field2) 4568 NO_THREAD_SAFETY_ANALYSIS { 4569 // First come reference fields, then 64-bit, then 32-bit, and then 16-bit, then finally 8-bit. 4570 Primitive::Type type1 = field1->GetTypeAsPrimitiveType(); 4571 Primitive::Type type2 = field2->GetTypeAsPrimitiveType(); 4572 if (type1 != type2) { 4573 if (type1 == Primitive::kPrimNot) { 4574 // Reference always goes first. 4575 return true; 4576 } 4577 if (type2 == Primitive::kPrimNot) { 4578 // Reference always goes first. 4579 return false; 4580 } 4581 size_t size1 = Primitive::ComponentSize(type1); 4582 size_t size2 = Primitive::ComponentSize(type2); 4583 if (size1 != size2) { 4584 // Larger primitive types go first. 4585 return size1 > size2; 4586 } 4587 // Primitive types differ but sizes match. Arbitrarily order by primitive type. 4588 return type1 < type2; 4589 } 4590 // Same basic group? Then sort by dex field index. This is guaranteed to be sorted 4591 // by name and for equal names by type id index. 4592 // NOTE: This works also for proxies. Their static fields are assigned appropriate indexes. 4593 return field1->GetDexFieldIndex() < field2->GetDexFieldIndex(); 4594 } 4595}; 4596 4597bool ClassLinker::LinkFields(Thread* self, Handle<mirror::Class> klass, bool is_static, 4598 size_t* class_size) { 4599 self->AllowThreadSuspension(); 4600 size_t num_fields = 4601 is_static ? klass->NumStaticFields() : klass->NumInstanceFields(); 4602 4603 mirror::ObjectArray<mirror::ArtField>* fields = 4604 is_static ? klass->GetSFields() : klass->GetIFields(); 4605 4606 // Initialize field_offset 4607 MemberOffset field_offset(0); 4608 if (is_static) { 4609 field_offset = klass->GetFirstReferenceStaticFieldOffsetDuringLinking(); 4610 } else { 4611 mirror::Class* super_class = klass->GetSuperClass(); 4612 if (super_class != nullptr) { 4613 CHECK(super_class->IsResolved()) 4614 << PrettyClass(klass.Get()) << " " << PrettyClass(super_class); 4615 field_offset = MemberOffset(super_class->GetObjectSize()); 4616 } 4617 } 4618 4619 CHECK_EQ(num_fields == 0, fields == nullptr) << PrettyClass(klass.Get()); 4620 4621 // we want a relatively stable order so that adding new fields 4622 // minimizes disruption of C++ version such as Class and Method. 4623 std::deque<mirror::ArtField*> grouped_and_sorted_fields; 4624 const char* old_no_suspend_cause = self->StartAssertNoThreadSuspension( 4625 "Naked ArtField references in deque"); 4626 for (size_t i = 0; i < num_fields; i++) { 4627 mirror::ArtField* f = fields->Get(i); 4628 CHECK(f != nullptr) << PrettyClass(klass.Get()); 4629 grouped_and_sorted_fields.push_back(f); 4630 } 4631 std::sort(grouped_and_sorted_fields.begin(), grouped_and_sorted_fields.end(), 4632 LinkFieldsComparator()); 4633 4634 // References should be at the front. 4635 size_t current_field = 0; 4636 size_t num_reference_fields = 0; 4637 FieldGaps gaps; 4638 4639 for (; current_field < num_fields; current_field++) { 4640 mirror::ArtField* field = grouped_and_sorted_fields.front(); 4641 Primitive::Type type = field->GetTypeAsPrimitiveType(); 4642 bool isPrimitive = type != Primitive::kPrimNot; 4643 if (isPrimitive) { 4644 break; // past last reference, move on to the next phase 4645 } 4646 if (UNLIKELY(!IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>( 4647 field_offset.Uint32Value()))) { 4648 MemberOffset old_offset = field_offset; 4649 field_offset = MemberOffset(RoundUp(field_offset.Uint32Value(), 4)); 4650 AddFieldGap(old_offset.Uint32Value(), field_offset.Uint32Value(), &gaps); 4651 } 4652 DCHECK(IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>(field_offset.Uint32Value())); 4653 grouped_and_sorted_fields.pop_front(); 4654 num_reference_fields++; 4655 field->SetOffset(field_offset); 4656 field_offset = MemberOffset(field_offset.Uint32Value() + 4657 sizeof(mirror::HeapReference<mirror::Object>)); 4658 } 4659 // Gaps are stored as a max heap which means that we must shuffle from largest to smallest 4660 // otherwise we could end up with suboptimal gap fills. 4661 ShuffleForward<8>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 4662 ShuffleForward<4>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 4663 ShuffleForward<2>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 4664 ShuffleForward<1>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 4665 CHECK(grouped_and_sorted_fields.empty()) << "Missed " << grouped_and_sorted_fields.size() << 4666 " fields."; 4667 self->EndAssertNoThreadSuspension(old_no_suspend_cause); 4668 4669 // We lie to the GC about the java.lang.ref.Reference.referent field, so it doesn't scan it. 4670 if (!is_static && klass->DescriptorEquals("Ljava/lang/ref/Reference;")) { 4671 // We know there are no non-reference fields in the Reference classes, and we know 4672 // that 'referent' is alphabetically last, so this is easy... 4673 CHECK_EQ(num_reference_fields, num_fields) << PrettyClass(klass.Get()); 4674 CHECK_STREQ(fields->Get(num_fields - 1)->GetName(), "referent") << PrettyClass(klass.Get()); 4675 --num_reference_fields; 4676 } 4677 4678 size_t size = field_offset.Uint32Value(); 4679 // Update klass 4680 if (is_static) { 4681 klass->SetNumReferenceStaticFields(num_reference_fields); 4682 *class_size = size; 4683 } else { 4684 klass->SetNumReferenceInstanceFields(num_reference_fields); 4685 if (!klass->IsVariableSize()) { 4686 if (klass->DescriptorEquals("Ljava/lang/reflect/ArtMethod;")) { 4687 size_t pointer_size = GetInstructionSetPointerSize(Runtime::Current()->GetInstructionSet()); 4688 klass->SetObjectSize(mirror::ArtMethod::InstanceSize(pointer_size)); 4689 } else { 4690 std::string temp; 4691 DCHECK_GE(size, sizeof(mirror::Object)) << klass->GetDescriptor(&temp); 4692 size_t previous_size = klass->GetObjectSize(); 4693 if (previous_size != 0) { 4694 // Make sure that we didn't originally have an incorrect size. 4695 CHECK_EQ(previous_size, size) << klass->GetDescriptor(&temp); 4696 } 4697 klass->SetObjectSize(size); 4698 } 4699 } 4700 } 4701 4702 if (kIsDebugBuild) { 4703 // Make sure that the fields array is ordered by name but all reference 4704 // offsets are at the beginning as far as alignment allows. 4705 MemberOffset start_ref_offset = is_static 4706 ? klass->GetFirstReferenceStaticFieldOffsetDuringLinking() 4707 : klass->GetFirstReferenceInstanceFieldOffset(); 4708 MemberOffset end_ref_offset(start_ref_offset.Uint32Value() + 4709 num_reference_fields * 4710 sizeof(mirror::HeapReference<mirror::Object>)); 4711 MemberOffset current_ref_offset = start_ref_offset; 4712 for (size_t i = 0; i < num_fields; i++) { 4713 mirror::ArtField* field = fields->Get(i); 4714 if ((false)) { // enable to debug field layout 4715 LOG(INFO) << "LinkFields: " << (is_static ? "static" : "instance") 4716 << " class=" << PrettyClass(klass.Get()) 4717 << " field=" << PrettyField(field) 4718 << " offset=" 4719 << field->GetField32(mirror::ArtField::OffsetOffset()); 4720 } 4721 if (i != 0) { 4722 mirror::ArtField* prev_field = fields->Get(i - 1u); 4723 // NOTE: The field names can be the same. This is not possible in the Java language 4724 // but it's valid Java/dex bytecode and for example proguard can generate such bytecode. 4725 CHECK_LE(strcmp(prev_field->GetName(), field->GetName()), 0); 4726 } 4727 Primitive::Type type = field->GetTypeAsPrimitiveType(); 4728 bool is_primitive = type != Primitive::kPrimNot; 4729 if (klass->DescriptorEquals("Ljava/lang/ref/Reference;") && 4730 strcmp("referent", field->GetName()) == 0) { 4731 is_primitive = true; // We lied above, so we have to expect a lie here. 4732 } 4733 MemberOffset offset = field->GetOffsetDuringLinking(); 4734 if (is_primitive) { 4735 if (offset.Uint32Value() < end_ref_offset.Uint32Value()) { 4736 // Shuffled before references. 4737 size_t type_size = Primitive::ComponentSize(type); 4738 CHECK_LT(type_size, sizeof(mirror::HeapReference<mirror::Object>)); 4739 CHECK_LT(offset.Uint32Value(), start_ref_offset.Uint32Value()); 4740 CHECK_LE(offset.Uint32Value() + type_size, start_ref_offset.Uint32Value()); 4741 CHECK(!IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>(offset.Uint32Value())); 4742 } 4743 } else { 4744 CHECK_EQ(current_ref_offset.Uint32Value(), offset.Uint32Value()); 4745 current_ref_offset = MemberOffset(current_ref_offset.Uint32Value() + 4746 sizeof(mirror::HeapReference<mirror::Object>)); 4747 } 4748 } 4749 CHECK_EQ(current_ref_offset.Uint32Value(), end_ref_offset.Uint32Value()); 4750 } 4751 return true; 4752} 4753 4754// Set the bitmap of reference instance field offsets. 4755void ClassLinker::CreateReferenceInstanceOffsets(Handle<mirror::Class> klass) { 4756 uint32_t reference_offsets = 0; 4757 mirror::Class* super_class = klass->GetSuperClass(); 4758 // Leave the reference offsets as 0 for mirror::Object (the class field is handled specially). 4759 if (super_class != nullptr) { 4760 reference_offsets = super_class->GetReferenceInstanceOffsets(); 4761 // Compute reference offsets unless our superclass overflowed. 4762 if (reference_offsets != mirror::Class::kClassWalkSuper) { 4763 size_t num_reference_fields = klass->NumReferenceInstanceFieldsDuringLinking(); 4764 if (num_reference_fields != 0u) { 4765 // All of the fields that contain object references are guaranteed be grouped in memory 4766 // starting at an appropriately aligned address after super class object data. 4767 uint32_t start_offset = RoundUp(super_class->GetObjectSize(), 4768 sizeof(mirror::HeapReference<mirror::Object>)); 4769 uint32_t start_bit = (start_offset - mirror::kObjectHeaderSize) / 4770 sizeof(mirror::HeapReference<mirror::Object>); 4771 if (start_bit + num_reference_fields > 32) { 4772 reference_offsets = mirror::Class::kClassWalkSuper; 4773 } else { 4774 reference_offsets |= (0xffffffffu << start_bit) & 4775 (0xffffffffu >> (32 - (start_bit + num_reference_fields))); 4776 } 4777 } 4778 } 4779 } 4780 klass->SetReferenceInstanceOffsets(reference_offsets); 4781} 4782 4783mirror::String* ClassLinker::ResolveString(const DexFile& dex_file, uint32_t string_idx, 4784 Handle<mirror::DexCache> dex_cache) { 4785 DCHECK(dex_cache.Get() != nullptr); 4786 mirror::String* resolved = dex_cache->GetResolvedString(string_idx); 4787 if (resolved != nullptr) { 4788 return resolved; 4789 } 4790 uint32_t utf16_length; 4791 const char* utf8_data = dex_file.StringDataAndUtf16LengthByIdx(string_idx, &utf16_length); 4792 mirror::String* string = intern_table_->InternStrong(utf16_length, utf8_data); 4793 dex_cache->SetResolvedString(string_idx, string); 4794 return string; 4795} 4796 4797mirror::Class* ClassLinker::ResolveType(const DexFile& dex_file, uint16_t type_idx, 4798 mirror::Class* referrer) { 4799 StackHandleScope<2> hs(Thread::Current()); 4800 Handle<mirror::DexCache> dex_cache(hs.NewHandle(referrer->GetDexCache())); 4801 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(referrer->GetClassLoader())); 4802 return ResolveType(dex_file, type_idx, dex_cache, class_loader); 4803} 4804 4805mirror::Class* ClassLinker::ResolveType(const DexFile& dex_file, uint16_t type_idx, 4806 Handle<mirror::DexCache> dex_cache, 4807 Handle<mirror::ClassLoader> class_loader) { 4808 DCHECK(dex_cache.Get() != nullptr); 4809 mirror::Class* resolved = dex_cache->GetResolvedType(type_idx); 4810 if (resolved == nullptr) { 4811 Thread* self = Thread::Current(); 4812 const char* descriptor = dex_file.StringByTypeIdx(type_idx); 4813 resolved = FindClass(self, descriptor, class_loader); 4814 if (resolved != nullptr) { 4815 // TODO: we used to throw here if resolved's class loader was not the 4816 // boot class loader. This was to permit different classes with the 4817 // same name to be loaded simultaneously by different loaders 4818 dex_cache->SetResolvedType(type_idx, resolved); 4819 } else { 4820 CHECK(self->IsExceptionPending()) 4821 << "Expected pending exception for failed resolution of: " << descriptor; 4822 // Convert a ClassNotFoundException to a NoClassDefFoundError. 4823 StackHandleScope<1> hs(self); 4824 Handle<mirror::Throwable> cause(hs.NewHandle(self->GetException())); 4825 if (cause->InstanceOf(GetClassRoot(kJavaLangClassNotFoundException))) { 4826 DCHECK(resolved == nullptr); // No Handle needed to preserve resolved. 4827 self->ClearException(); 4828 ThrowNoClassDefFoundError("Failed resolution of: %s", descriptor); 4829 self->GetException()->SetCause(cause.Get()); 4830 } 4831 } 4832 } 4833 DCHECK((resolved == nullptr) || resolved->IsResolved() || resolved->IsErroneous()) 4834 << PrettyDescriptor(resolved) << " " << resolved->GetStatus(); 4835 return resolved; 4836} 4837 4838mirror::ArtMethod* ClassLinker::ResolveMethod(const DexFile& dex_file, uint32_t method_idx, 4839 Handle<mirror::DexCache> dex_cache, 4840 Handle<mirror::ClassLoader> class_loader, 4841 Handle<mirror::ArtMethod> referrer, 4842 InvokeType type) { 4843 DCHECK(dex_cache.Get() != nullptr); 4844 // Check for hit in the dex cache. 4845 mirror::ArtMethod* resolved = dex_cache->GetResolvedMethod(method_idx); 4846 if (resolved != nullptr && !resolved->IsRuntimeMethod()) { 4847 return resolved; 4848 } 4849 // Fail, get the declaring class. 4850 const DexFile::MethodId& method_id = dex_file.GetMethodId(method_idx); 4851 mirror::Class* klass = ResolveType(dex_file, method_id.class_idx_, dex_cache, class_loader); 4852 if (klass == nullptr) { 4853 DCHECK(Thread::Current()->IsExceptionPending()); 4854 return nullptr; 4855 } 4856 // Scan using method_idx, this saves string compares but will only hit for matching dex 4857 // caches/files. 4858 switch (type) { 4859 case kDirect: // Fall-through. 4860 case kStatic: 4861 resolved = klass->FindDirectMethod(dex_cache.Get(), method_idx); 4862 break; 4863 case kInterface: 4864 resolved = klass->FindInterfaceMethod(dex_cache.Get(), method_idx); 4865 DCHECK(resolved == nullptr || resolved->GetDeclaringClass()->IsInterface()); 4866 break; 4867 case kSuper: // Fall-through. 4868 case kVirtual: 4869 resolved = klass->FindVirtualMethod(dex_cache.Get(), method_idx); 4870 break; 4871 default: 4872 LOG(FATAL) << "Unreachable - invocation type: " << type; 4873 UNREACHABLE(); 4874 } 4875 if (resolved == nullptr) { 4876 // Search by name, which works across dex files. 4877 const char* name = dex_file.StringDataByIdx(method_id.name_idx_); 4878 const Signature signature = dex_file.GetMethodSignature(method_id); 4879 switch (type) { 4880 case kDirect: // Fall-through. 4881 case kStatic: 4882 resolved = klass->FindDirectMethod(name, signature); 4883 break; 4884 case kInterface: 4885 resolved = klass->FindInterfaceMethod(name, signature); 4886 DCHECK(resolved == nullptr || resolved->GetDeclaringClass()->IsInterface()); 4887 break; 4888 case kSuper: // Fall-through. 4889 case kVirtual: 4890 resolved = klass->FindVirtualMethod(name, signature); 4891 break; 4892 } 4893 } 4894 // If we found a method, check for incompatible class changes. 4895 if (LIKELY(resolved != nullptr && !resolved->CheckIncompatibleClassChange(type))) { 4896 // Be a good citizen and update the dex cache to speed subsequent calls. 4897 dex_cache->SetResolvedMethod(method_idx, resolved); 4898 return resolved; 4899 } else { 4900 // If we had a method, it's an incompatible-class-change error. 4901 if (resolved != nullptr) { 4902 ThrowIncompatibleClassChangeError(type, resolved->GetInvokeType(), resolved, referrer.Get()); 4903 } else { 4904 // We failed to find the method which means either an access error, an incompatible class 4905 // change, or no such method. First try to find the method among direct and virtual methods. 4906 const char* name = dex_file.StringDataByIdx(method_id.name_idx_); 4907 const Signature signature = dex_file.GetMethodSignature(method_id); 4908 switch (type) { 4909 case kDirect: 4910 case kStatic: 4911 resolved = klass->FindVirtualMethod(name, signature); 4912 // Note: kDirect and kStatic are also mutually exclusive, but in that case we would 4913 // have had a resolved method before, which triggers the "true" branch above. 4914 break; 4915 case kInterface: 4916 case kVirtual: 4917 case kSuper: 4918 resolved = klass->FindDirectMethod(name, signature); 4919 break; 4920 } 4921 4922 // If we found something, check that it can be accessed by the referrer. 4923 bool exception_generated = false; 4924 if (resolved != nullptr && referrer.Get() != nullptr) { 4925 mirror::Class* methods_class = resolved->GetDeclaringClass(); 4926 mirror::Class* referring_class = referrer->GetDeclaringClass(); 4927 if (!referring_class->CanAccess(methods_class)) { 4928 ThrowIllegalAccessErrorClassForMethodDispatch(referring_class, methods_class, 4929 resolved, type); 4930 exception_generated = true; 4931 } else if (!referring_class->CanAccessMember(methods_class, 4932 resolved->GetAccessFlags())) { 4933 ThrowIllegalAccessErrorMethod(referring_class, resolved); 4934 exception_generated = true; 4935 } 4936 } 4937 if (!exception_generated) { 4938 // Otherwise, throw an IncompatibleClassChangeError if we found something, and check 4939 // interface methods and throw if we find the method there. If we find nothing, throw a 4940 // NoSuchMethodError. 4941 switch (type) { 4942 case kDirect: 4943 case kStatic: 4944 if (resolved != nullptr) { 4945 ThrowIncompatibleClassChangeError(type, kVirtual, resolved, referrer.Get()); 4946 } else { 4947 resolved = klass->FindInterfaceMethod(name, signature); 4948 if (resolved != nullptr) { 4949 ThrowIncompatibleClassChangeError(type, kInterface, resolved, referrer.Get()); 4950 } else { 4951 ThrowNoSuchMethodError(type, klass, name, signature); 4952 } 4953 } 4954 break; 4955 case kInterface: 4956 if (resolved != nullptr) { 4957 ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer.Get()); 4958 } else { 4959 resolved = klass->FindVirtualMethod(name, signature); 4960 if (resolved != nullptr) { 4961 ThrowIncompatibleClassChangeError(type, kVirtual, resolved, referrer.Get()); 4962 } else { 4963 ThrowNoSuchMethodError(type, klass, name, signature); 4964 } 4965 } 4966 break; 4967 case kSuper: 4968 if (resolved != nullptr) { 4969 ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer.Get()); 4970 } else { 4971 ThrowNoSuchMethodError(type, klass, name, signature); 4972 } 4973 break; 4974 case kVirtual: 4975 if (resolved != nullptr) { 4976 ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer.Get()); 4977 } else { 4978 resolved = klass->FindInterfaceMethod(name, signature); 4979 if (resolved != nullptr) { 4980 ThrowIncompatibleClassChangeError(type, kInterface, resolved, referrer.Get()); 4981 } else { 4982 ThrowNoSuchMethodError(type, klass, name, signature); 4983 } 4984 } 4985 break; 4986 } 4987 } 4988 } 4989 Thread::Current()->AssertPendingException(); 4990 return nullptr; 4991 } 4992} 4993 4994mirror::ArtField* ClassLinker::ResolveField(const DexFile& dex_file, uint32_t field_idx, 4995 Handle<mirror::DexCache> dex_cache, 4996 Handle<mirror::ClassLoader> class_loader, 4997 bool is_static) { 4998 DCHECK(dex_cache.Get() != nullptr); 4999 mirror::ArtField* resolved = dex_cache->GetResolvedField(field_idx); 5000 if (resolved != nullptr) { 5001 return resolved; 5002 } 5003 const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx); 5004 Thread* const self = Thread::Current(); 5005 StackHandleScope<1> hs(self); 5006 Handle<mirror::Class> klass( 5007 hs.NewHandle(ResolveType(dex_file, field_id.class_idx_, dex_cache, class_loader))); 5008 if (klass.Get() == nullptr) { 5009 DCHECK(Thread::Current()->IsExceptionPending()); 5010 return nullptr; 5011 } 5012 5013 if (is_static) { 5014 resolved = mirror::Class::FindStaticField(self, klass, dex_cache.Get(), field_idx); 5015 } else { 5016 resolved = klass->FindInstanceField(dex_cache.Get(), field_idx); 5017 } 5018 5019 if (resolved == nullptr) { 5020 const char* name = dex_file.GetFieldName(field_id); 5021 const char* type = dex_file.GetFieldTypeDescriptor(field_id); 5022 if (is_static) { 5023 resolved = mirror::Class::FindStaticField(self, klass, name, type); 5024 } else { 5025 resolved = klass->FindInstanceField(name, type); 5026 } 5027 if (resolved == nullptr) { 5028 ThrowNoSuchFieldError(is_static ? "static " : "instance ", klass.Get(), type, name); 5029 return nullptr; 5030 } 5031 } 5032 dex_cache->SetResolvedField(field_idx, resolved); 5033 return resolved; 5034} 5035 5036mirror::ArtField* ClassLinker::ResolveFieldJLS(const DexFile& dex_file, 5037 uint32_t field_idx, 5038 Handle<mirror::DexCache> dex_cache, 5039 Handle<mirror::ClassLoader> class_loader) { 5040 DCHECK(dex_cache.Get() != nullptr); 5041 mirror::ArtField* resolved = dex_cache->GetResolvedField(field_idx); 5042 if (resolved != nullptr) { 5043 return resolved; 5044 } 5045 const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx); 5046 Thread* self = Thread::Current(); 5047 StackHandleScope<1> hs(self); 5048 Handle<mirror::Class> klass( 5049 hs.NewHandle(ResolveType(dex_file, field_id.class_idx_, dex_cache, class_loader))); 5050 if (klass.Get() == nullptr) { 5051 DCHECK(Thread::Current()->IsExceptionPending()); 5052 return nullptr; 5053 } 5054 5055 StringPiece name(dex_file.StringDataByIdx(field_id.name_idx_)); 5056 StringPiece type(dex_file.StringDataByIdx( 5057 dex_file.GetTypeId(field_id.type_idx_).descriptor_idx_)); 5058 resolved = mirror::Class::FindField(self, klass, name, type); 5059 if (resolved != nullptr) { 5060 dex_cache->SetResolvedField(field_idx, resolved); 5061 } else { 5062 ThrowNoSuchFieldError("", klass.Get(), type, name); 5063 } 5064 return resolved; 5065} 5066 5067const char* ClassLinker::MethodShorty(uint32_t method_idx, mirror::ArtMethod* referrer, 5068 uint32_t* length) { 5069 mirror::Class* declaring_class = referrer->GetDeclaringClass(); 5070 mirror::DexCache* dex_cache = declaring_class->GetDexCache(); 5071 const DexFile& dex_file = *dex_cache->GetDexFile(); 5072 const DexFile::MethodId& method_id = dex_file.GetMethodId(method_idx); 5073 return dex_file.GetMethodShorty(method_id, length); 5074} 5075 5076void ClassLinker::DumpAllClasses(int flags) { 5077 if (dex_cache_image_class_lookup_required_) { 5078 MoveImageClassesToClassTable(); 5079 } 5080 // TODO: at the time this was written, it wasn't safe to call PrettyField with the ClassLinker 5081 // lock held, because it might need to resolve a field's type, which would try to take the lock. 5082 std::vector<mirror::Class*> all_classes; 5083 { 5084 ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 5085 for (GcRoot<mirror::Class>& it : class_table_) { 5086 all_classes.push_back(it.Read()); 5087 } 5088 } 5089 5090 for (size_t i = 0; i < all_classes.size(); ++i) { 5091 all_classes[i]->DumpClass(std::cerr, flags); 5092 } 5093} 5094 5095static OatFile::OatMethod CreateOatMethod(const void* code) { 5096 CHECK(code != nullptr); 5097 const uint8_t* base = reinterpret_cast<const uint8_t*>(code); // Base of data points at code. 5098 base -= sizeof(void*); // Move backward so that code_offset != 0. 5099 const uint32_t code_offset = sizeof(void*); 5100 return OatFile::OatMethod(base, code_offset); 5101} 5102 5103bool ClassLinker::IsQuickResolutionStub(const void* entry_point) const { 5104 return (entry_point == GetQuickResolutionStub()) || 5105 (quick_resolution_trampoline_ == entry_point); 5106} 5107 5108bool ClassLinker::IsQuickToInterpreterBridge(const void* entry_point) const { 5109 return (entry_point == GetQuickToInterpreterBridge()) || 5110 (quick_to_interpreter_bridge_trampoline_ == entry_point); 5111} 5112 5113bool ClassLinker::IsQuickGenericJniStub(const void* entry_point) const { 5114 return (entry_point == GetQuickGenericJniStub()) || 5115 (quick_generic_jni_trampoline_ == entry_point); 5116} 5117 5118const void* ClassLinker::GetRuntimeQuickGenericJniStub() const { 5119 return GetQuickGenericJniStub(); 5120} 5121 5122void ClassLinker::SetEntryPointsToCompiledCode(mirror::ArtMethod* method, 5123 const void* method_code) const { 5124 OatFile::OatMethod oat_method = CreateOatMethod(method_code); 5125 oat_method.LinkMethod(method); 5126 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 5127} 5128 5129void ClassLinker::SetEntryPointsToInterpreter(mirror::ArtMethod* method) const { 5130 if (!method->IsNative()) { 5131 method->SetEntryPointFromInterpreter(artInterpreterToInterpreterBridge); 5132 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge()); 5133 } else { 5134 const void* quick_method_code = GetQuickGenericJniStub(); 5135 OatFile::OatMethod oat_method = CreateOatMethod(quick_method_code); 5136 oat_method.LinkMethod(method); 5137 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 5138 } 5139} 5140 5141void ClassLinker::DumpForSigQuit(std::ostream& os) { 5142 Thread* self = Thread::Current(); 5143 if (dex_cache_image_class_lookup_required_) { 5144 ScopedObjectAccess soa(self); 5145 MoveImageClassesToClassTable(); 5146 } 5147 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 5148 os << "Zygote loaded classes=" << pre_zygote_class_table_.Size() << " post zygote classes=" 5149 << class_table_.Size() << "\n"; 5150} 5151 5152size_t ClassLinker::NumLoadedClasses() { 5153 if (dex_cache_image_class_lookup_required_) { 5154 MoveImageClassesToClassTable(); 5155 } 5156 ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 5157 // Only return non zygote classes since these are the ones which apps which care about. 5158 return class_table_.Size(); 5159} 5160 5161pid_t ClassLinker::GetClassesLockOwner() { 5162 return Locks::classlinker_classes_lock_->GetExclusiveOwnerTid(); 5163} 5164 5165pid_t ClassLinker::GetDexLockOwner() { 5166 return dex_lock_.GetExclusiveOwnerTid(); 5167} 5168 5169void ClassLinker::SetClassRoot(ClassRoot class_root, mirror::Class* klass) { 5170 DCHECK(!init_done_); 5171 5172 DCHECK(klass != nullptr); 5173 DCHECK(klass->GetClassLoader() == nullptr); 5174 5175 mirror::ObjectArray<mirror::Class>* class_roots = class_roots_.Read(); 5176 DCHECK(class_roots != nullptr); 5177 DCHECK(class_roots->Get(class_root) == nullptr); 5178 class_roots->Set<false>(class_root, klass); 5179} 5180 5181const char* ClassLinker::GetClassRootDescriptor(ClassRoot class_root) { 5182 static const char* class_roots_descriptors[] = { 5183 "Ljava/lang/Class;", 5184 "Ljava/lang/Object;", 5185 "[Ljava/lang/Class;", 5186 "[Ljava/lang/Object;", 5187 "Ljava/lang/String;", 5188 "Ljava/lang/DexCache;", 5189 "Ljava/lang/ref/Reference;", 5190 "Ljava/lang/reflect/ArtField;", 5191 "Ljava/lang/reflect/ArtMethod;", 5192 "Ljava/lang/reflect/Proxy;", 5193 "[Ljava/lang/String;", 5194 "[Ljava/lang/reflect/ArtField;", 5195 "[Ljava/lang/reflect/ArtMethod;", 5196 "Ljava/lang/ClassLoader;", 5197 "Ljava/lang/Throwable;", 5198 "Ljava/lang/ClassNotFoundException;", 5199 "Ljava/lang/StackTraceElement;", 5200 "Z", 5201 "B", 5202 "C", 5203 "D", 5204 "F", 5205 "I", 5206 "J", 5207 "S", 5208 "V", 5209 "[Z", 5210 "[B", 5211 "[C", 5212 "[D", 5213 "[F", 5214 "[I", 5215 "[J", 5216 "[S", 5217 "[Ljava/lang/StackTraceElement;", 5218 }; 5219 static_assert(arraysize(class_roots_descriptors) == size_t(kClassRootsMax), 5220 "Mismatch between class descriptors and class-root enum"); 5221 5222 const char* descriptor = class_roots_descriptors[class_root]; 5223 CHECK(descriptor != nullptr); 5224 return descriptor; 5225} 5226 5227std::size_t ClassLinker::ClassDescriptorHashEquals::operator()(const GcRoot<mirror::Class>& root) 5228 const { 5229 std::string temp; 5230 return ComputeModifiedUtf8Hash(root.Read()->GetDescriptor(&temp)); 5231} 5232 5233bool ClassLinker::ClassDescriptorHashEquals::operator()(const GcRoot<mirror::Class>& a, 5234 const GcRoot<mirror::Class>& b) const { 5235 if (a.Read()->GetClassLoader() != b.Read()->GetClassLoader()) { 5236 return false; 5237 } 5238 std::string temp; 5239 return a.Read()->DescriptorEquals(b.Read()->GetDescriptor(&temp)); 5240} 5241 5242std::size_t ClassLinker::ClassDescriptorHashEquals::operator()( 5243 const std::pair<const char*, mirror::ClassLoader*>& element) const { 5244 return ComputeModifiedUtf8Hash(element.first); 5245} 5246 5247bool ClassLinker::ClassDescriptorHashEquals::operator()( 5248 const GcRoot<mirror::Class>& a, const std::pair<const char*, mirror::ClassLoader*>& b) const { 5249 if (a.Read()->GetClassLoader() != b.second) { 5250 return false; 5251 } 5252 return a.Read()->DescriptorEquals(b.first); 5253} 5254 5255bool ClassLinker::ClassDescriptorHashEquals::operator()(const GcRoot<mirror::Class>& a, 5256 const char* descriptor) const { 5257 return a.Read()->DescriptorEquals(descriptor); 5258} 5259 5260std::size_t ClassLinker::ClassDescriptorHashEquals::operator()(const char* descriptor) const { 5261 return ComputeModifiedUtf8Hash(descriptor); 5262} 5263 5264bool ClassLinker::MayBeCalledWithDirectCodePointer(mirror::ArtMethod* m) { 5265 if (Runtime::Current()->UseJit()) { 5266 // JIT can have direct code pointers from any method to any other method. 5267 return true; 5268 } 5269 // Non-image methods don't use direct code pointer. 5270 if (!m->GetDeclaringClass()->IsBootStrapClassLoaded()) { 5271 return false; 5272 } 5273 if (m->IsPrivate()) { 5274 // The method can only be called inside its own oat file. Therefore it won't be called using 5275 // its direct code if the oat file has been compiled in PIC mode. 5276 ClassLinker* class_linker = Runtime::Current()->GetClassLinker(); 5277 const DexFile& dex_file = m->GetDeclaringClass()->GetDexFile(); 5278 const OatFile::OatDexFile* oat_dex_file = class_linker->FindOpenedOatDexFileForDexFile(dex_file); 5279 if (oat_dex_file == nullptr) { 5280 // No oat file: the method has not been compiled. 5281 return false; 5282 } 5283 const OatFile* oat_file = oat_dex_file->GetOatFile(); 5284 return oat_file != nullptr && !oat_file->IsPic(); 5285 } else { 5286 // The method can be called outside its own oat file. Therefore it won't be called using its 5287 // direct code pointer only if all loaded oat files have been compiled in PIC mode. 5288 ReaderMutexLock mu(Thread::Current(), dex_lock_); 5289 for (const OatFile* oat_file : oat_files_) { 5290 if (!oat_file->IsPic()) { 5291 return true; 5292 } 5293 } 5294 return false; 5295 } 5296} 5297 5298jobject ClassLinker::CreatePathClassLoader(Thread* self, std::vector<const DexFile*>& dex_files) { 5299 // SOAAlreadyRunnable is protected, and we need something to add a global reference. 5300 // We could move the jobject to the callers, but all call-sites do this... 5301 ScopedObjectAccessUnchecked soa(self); 5302 5303 // Register the dex files. 5304 for (const DexFile* dex_file : dex_files) { 5305 RegisterDexFile(*dex_file); 5306 } 5307 5308 // For now, create a libcore-level DexFile for each ART DexFile. This "explodes" multidex. 5309 StackHandleScope<11> hs(self); 5310 5311 Handle<mirror::ArtField> h_dex_elements_field = 5312 hs.NewHandle(soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList_dexElements)); 5313 5314 mirror::Class* dex_elements_class = h_dex_elements_field->GetType(true); 5315 DCHECK(dex_elements_class != nullptr); 5316 DCHECK(dex_elements_class->IsArrayClass()); 5317 Handle<mirror::ObjectArray<mirror::Object>> h_dex_elements = 5318 hs.NewHandle(reinterpret_cast<mirror::ObjectArray<mirror::Object>*>( 5319 mirror::Array::Alloc<true>(self, dex_elements_class, dex_files.size(), 5320 dex_elements_class->GetComponentSizeShift(), 5321 Runtime::Current()->GetHeap()->GetCurrentAllocator()))); 5322 Handle<mirror::Class> h_dex_element_class = 5323 hs.NewHandle(dex_elements_class->GetComponentType()); 5324 5325 Handle<mirror::ArtField> h_element_file_field = 5326 hs.NewHandle( 5327 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList__Element_dexFile)); 5328 DCHECK_EQ(h_dex_element_class.Get(), h_element_file_field->GetDeclaringClass()); 5329 5330 Handle<mirror::ArtField> h_cookie_field = 5331 hs.NewHandle(soa.DecodeField(WellKnownClasses::dalvik_system_DexFile_cookie)); 5332 DCHECK_EQ(h_cookie_field->GetDeclaringClass(), h_element_file_field->GetType(false)); 5333 5334 // Fill the elements array. 5335 int32_t index = 0; 5336 for (const DexFile* dex_file : dex_files) { 5337 StackHandleScope<3> hs2(self); 5338 5339 Handle<mirror::LongArray> h_long_array = hs2.NewHandle(mirror::LongArray::Alloc(self, 1)); 5340 DCHECK(h_long_array.Get() != nullptr); 5341 h_long_array->Set(0, reinterpret_cast<intptr_t>(dex_file)); 5342 5343 Handle<mirror::Object> h_dex_file = hs2.NewHandle( 5344 h_cookie_field->GetDeclaringClass()->AllocObject(self)); 5345 DCHECK(h_dex_file.Get() != nullptr); 5346 h_cookie_field->SetObject<false>(h_dex_file.Get(), h_long_array.Get()); 5347 5348 Handle<mirror::Object> h_element = hs2.NewHandle(h_dex_element_class->AllocObject(self)); 5349 DCHECK(h_element.Get() != nullptr); 5350 h_element_file_field->SetObject<false>(h_element.Get(), h_dex_file.Get()); 5351 5352 h_dex_elements->Set(index, h_element.Get()); 5353 index++; 5354 } 5355 DCHECK_EQ(index, h_dex_elements->GetLength()); 5356 5357 // Create DexPathList. 5358 Handle<mirror::Object> h_dex_path_list = hs.NewHandle( 5359 h_dex_elements_field->GetDeclaringClass()->AllocObject(self)); 5360 DCHECK(h_dex_path_list.Get() != nullptr); 5361 // Set elements. 5362 h_dex_elements_field->SetObject<false>(h_dex_path_list.Get(), h_dex_elements.Get()); 5363 5364 // Create PathClassLoader. 5365 Handle<mirror::Class> h_path_class_class = hs.NewHandle( 5366 soa.Decode<mirror::Class*>(WellKnownClasses::dalvik_system_PathClassLoader)); 5367 Handle<mirror::Object> h_path_class_loader = hs.NewHandle( 5368 h_path_class_class->AllocObject(self)); 5369 DCHECK(h_path_class_loader.Get() != nullptr); 5370 // Set DexPathList. 5371 Handle<mirror::ArtField> h_path_list_field = hs.NewHandle( 5372 soa.DecodeField(WellKnownClasses::dalvik_system_PathClassLoader_pathList)); 5373 DCHECK(h_path_list_field.Get() != nullptr); 5374 h_path_list_field->SetObject<false>(h_path_class_loader.Get(), h_dex_path_list.Get()); 5375 5376 // Make a pretend boot-classpath. 5377 // TODO: Should we scan the image? 5378 Handle<mirror::ArtField> h_parent_field = hs.NewHandle( 5379 mirror::Class::FindField(self, hs.NewHandle(h_path_class_loader->GetClass()), "parent", 5380 "Ljava/lang/ClassLoader;")); 5381 DCHECK(h_parent_field.Get() != nullptr); 5382 mirror::Object* boot_cl = 5383 soa.Decode<mirror::Class*>(WellKnownClasses::java_lang_BootClassLoader)->AllocObject(self); 5384 h_parent_field->SetObject<false>(h_path_class_loader.Get(), boot_cl); 5385 5386 // Make it a global ref and return. 5387 ScopedLocalRef<jobject> local_ref( 5388 soa.Env(), soa.Env()->AddLocalReference<jobject>(h_path_class_loader.Get())); 5389 return soa.Env()->NewGlobalRef(local_ref.get()); 5390} 5391 5392} // namespace art 5393