class_linker.cc revision bad9c7b7f88689133cae59d9ccae231822a2020c
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 "art_field-inl.h" 29#include "art_method-inl.h" 30#include "base/arena_allocator.h" 31#include "base/casts.h" 32#include "base/logging.h" 33#include "base/scoped_arena_containers.h" 34#include "base/scoped_flock.h" 35#include "base/stl_util.h" 36#include "base/time_utils.h" 37#include "base/unix_file/fd_file.h" 38#include "base/value_object.h" 39#include "class_linker-inl.h" 40#include "compiler_callbacks.h" 41#include "debugger.h" 42#include "dex_file-inl.h" 43#include "entrypoints/runtime_asm_entrypoints.h" 44#include "gc_root-inl.h" 45#include "gc/accounting/card_table-inl.h" 46#include "gc/accounting/heap_bitmap.h" 47#include "gc/heap.h" 48#include "gc/space/image_space.h" 49#include "handle_scope.h" 50#include "intern_table.h" 51#include "interpreter/interpreter.h" 52#include "jit/jit.h" 53#include "jit/jit_code_cache.h" 54#include "leb128.h" 55#include "linear_alloc.h" 56#include "oat.h" 57#include "oat_file.h" 58#include "oat_file_assistant.h" 59#include "object_lock.h" 60#include "mirror/class.h" 61#include "mirror/class-inl.h" 62#include "mirror/class_loader.h" 63#include "mirror/dex_cache-inl.h" 64#include "mirror/field.h" 65#include "mirror/iftable-inl.h" 66#include "mirror/method.h" 67#include "mirror/object-inl.h" 68#include "mirror/object_array-inl.h" 69#include "mirror/proxy.h" 70#include "mirror/reference-inl.h" 71#include "mirror/stack_trace_element.h" 72#include "mirror/string-inl.h" 73#include "os.h" 74#include "runtime.h" 75#include "entrypoints/entrypoint_utils.h" 76#include "ScopedLocalRef.h" 77#include "scoped_thread_state_change.h" 78#include "handle_scope-inl.h" 79#include "thread-inl.h" 80#include "utils.h" 81#include "verifier/method_verifier.h" 82#include "well_known_classes.h" 83 84namespace art { 85 86static constexpr bool kSanityCheckObjects = kIsDebugBuild; 87 88// For b/21333911. 89static constexpr bool kDuplicateClassesCheck = false; 90 91static void ThrowNoClassDefFoundError(const char* fmt, ...) 92 __attribute__((__format__(__printf__, 1, 2))) 93 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 94static void ThrowNoClassDefFoundError(const char* fmt, ...) { 95 va_list args; 96 va_start(args, fmt); 97 Thread* self = Thread::Current(); 98 self->ThrowNewExceptionV("Ljava/lang/NoClassDefFoundError;", fmt, args); 99 va_end(args); 100} 101 102bool ClassLinker::HasInitWithString( 103 Thread* self, ClassLinker* class_linker, const char* descriptor) { 104 ArtMethod* method = self->GetCurrentMethod(nullptr); 105 StackHandleScope<1> hs(self); 106 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(method != nullptr ? 107 method->GetDeclaringClass()->GetClassLoader() 108 : nullptr)); 109 mirror::Class* exception_class = class_linker->FindClass(self, descriptor, class_loader); 110 111 if (exception_class == nullptr) { 112 // No exc class ~ no <init>-with-string. 113 CHECK(self->IsExceptionPending()); 114 self->ClearException(); 115 return false; 116 } 117 118 ArtMethod* exception_init_method = exception_class->FindDeclaredDirectMethod( 119 "<init>", "(Ljava/lang/String;)V", image_pointer_size_); 120 return exception_init_method != nullptr; 121} 122 123void ClassLinker::ThrowEarlierClassFailure(mirror::Class* c) { 124 // The class failed to initialize on a previous attempt, so we want to throw 125 // a NoClassDefFoundError (v2 2.17.5). The exception to this rule is if we 126 // failed in verification, in which case v2 5.4.1 says we need to re-throw 127 // the previous error. 128 Runtime* const runtime = Runtime::Current(); 129 if (!runtime->IsAotCompiler()) { // Give info if this occurs at runtime. 130 LOG(INFO) << "Rejecting re-init on previously-failed class " << PrettyClass(c); 131 } 132 133 CHECK(c->IsErroneous()) << PrettyClass(c) << " " << c->GetStatus(); 134 Thread* self = Thread::Current(); 135 if (runtime->IsAotCompiler()) { 136 // At compile time, accurate errors and NCDFE are disabled to speed compilation. 137 mirror::Throwable* pre_allocated = runtime->GetPreAllocatedNoClassDefFoundError(); 138 self->SetException(pre_allocated); 139 } else { 140 if (c->GetVerifyErrorClass() != nullptr) { 141 // TODO: change the verifier to store an _instance_, with a useful detail message? 142 // It's possible the exception doesn't have a <init>(String). 143 std::string temp; 144 const char* descriptor = c->GetVerifyErrorClass()->GetDescriptor(&temp); 145 146 if (HasInitWithString(self, this, descriptor)) { 147 self->ThrowNewException(descriptor, PrettyDescriptor(c).c_str()); 148 } else { 149 self->ThrowNewException(descriptor, nullptr); 150 } 151 } else { 152 self->ThrowNewException("Ljava/lang/NoClassDefFoundError;", 153 PrettyDescriptor(c).c_str()); 154 } 155 } 156} 157 158static void VlogClassInitializationFailure(Handle<mirror::Class> klass) 159 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 160 if (VLOG_IS_ON(class_linker)) { 161 std::string temp; 162 LOG(INFO) << "Failed to initialize class " << klass->GetDescriptor(&temp) << " from " 163 << klass->GetLocation() << "\n" << Thread::Current()->GetException()->Dump(); 164 } 165} 166 167static void WrapExceptionInInitializer(Handle<mirror::Class> klass) 168 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 169 Thread* self = Thread::Current(); 170 JNIEnv* env = self->GetJniEnv(); 171 172 ScopedLocalRef<jthrowable> cause(env, env->ExceptionOccurred()); 173 CHECK(cause.get() != nullptr); 174 175 env->ExceptionClear(); 176 bool is_error = env->IsInstanceOf(cause.get(), WellKnownClasses::java_lang_Error); 177 env->Throw(cause.get()); 178 179 // We only wrap non-Error exceptions; an Error can just be used as-is. 180 if (!is_error) { 181 self->ThrowNewWrappedException("Ljava/lang/ExceptionInInitializerError;", nullptr); 182 } 183 VlogClassInitializationFailure(klass); 184} 185 186// Gap between two fields in object layout. 187struct FieldGap { 188 uint32_t start_offset; // The offset from the start of the object. 189 uint32_t size; // The gap size of 1, 2, or 4 bytes. 190}; 191struct FieldGapsComparator { 192 explicit FieldGapsComparator() { 193 } 194 bool operator() (const FieldGap& lhs, const FieldGap& rhs) 195 NO_THREAD_SAFETY_ANALYSIS { 196 // Sort by gap size, largest first. Secondary sort by starting offset. 197 return lhs.size > rhs.size || (lhs.size == rhs.size && lhs.start_offset < rhs.start_offset); 198 } 199}; 200typedef std::priority_queue<FieldGap, std::vector<FieldGap>, FieldGapsComparator> FieldGaps; 201 202// Adds largest aligned gaps to queue of gaps. 203static void AddFieldGap(uint32_t gap_start, uint32_t gap_end, FieldGaps* gaps) { 204 DCHECK(gaps != nullptr); 205 206 uint32_t current_offset = gap_start; 207 while (current_offset != gap_end) { 208 size_t remaining = gap_end - current_offset; 209 if (remaining >= sizeof(uint32_t) && IsAligned<4>(current_offset)) { 210 gaps->push(FieldGap {current_offset, sizeof(uint32_t)}); 211 current_offset += sizeof(uint32_t); 212 } else if (remaining >= sizeof(uint16_t) && IsAligned<2>(current_offset)) { 213 gaps->push(FieldGap {current_offset, sizeof(uint16_t)}); 214 current_offset += sizeof(uint16_t); 215 } else { 216 gaps->push(FieldGap {current_offset, sizeof(uint8_t)}); 217 current_offset += sizeof(uint8_t); 218 } 219 DCHECK_LE(current_offset, gap_end) << "Overran gap"; 220 } 221} 222// Shuffle fields forward, making use of gaps whenever possible. 223template<int n> 224static void ShuffleForward(size_t* current_field_idx, 225 MemberOffset* field_offset, 226 std::deque<ArtField*>* grouped_and_sorted_fields, 227 FieldGaps* gaps) 228 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 229 DCHECK(current_field_idx != nullptr); 230 DCHECK(grouped_and_sorted_fields != nullptr); 231 DCHECK(gaps != nullptr); 232 DCHECK(field_offset != nullptr); 233 234 DCHECK(IsPowerOfTwo(n)); 235 while (!grouped_and_sorted_fields->empty()) { 236 ArtField* field = grouped_and_sorted_fields->front(); 237 Primitive::Type type = field->GetTypeAsPrimitiveType(); 238 if (Primitive::ComponentSize(type) < n) { 239 break; 240 } 241 if (!IsAligned<n>(field_offset->Uint32Value())) { 242 MemberOffset old_offset = *field_offset; 243 *field_offset = MemberOffset(RoundUp(field_offset->Uint32Value(), n)); 244 AddFieldGap(old_offset.Uint32Value(), field_offset->Uint32Value(), gaps); 245 } 246 CHECK(type != Primitive::kPrimNot) << PrettyField(field); // should be primitive types 247 grouped_and_sorted_fields->pop_front(); 248 if (!gaps->empty() && gaps->top().size >= n) { 249 FieldGap gap = gaps->top(); 250 gaps->pop(); 251 DCHECK(IsAligned<n>(gap.start_offset)); 252 field->SetOffset(MemberOffset(gap.start_offset)); 253 if (gap.size > n) { 254 AddFieldGap(gap.start_offset + n, gap.start_offset + gap.size, gaps); 255 } 256 } else { 257 DCHECK(IsAligned<n>(field_offset->Uint32Value())); 258 field->SetOffset(*field_offset); 259 *field_offset = MemberOffset(field_offset->Uint32Value() + n); 260 } 261 ++(*current_field_idx); 262 } 263} 264 265ClassLinker::ClassLinker(InternTable* intern_table) 266 // dex_lock_ is recursive as it may be used in stack dumping. 267 : dex_lock_("ClassLinker dex lock", kDefaultMutexLevel), 268 dex_cache_image_class_lookup_required_(false), 269 failed_dex_cache_class_lookups_(0), 270 class_roots_(nullptr), 271 array_iftable_(nullptr), 272 find_array_class_cache_next_victim_(0), 273 init_done_(false), 274 log_new_dex_caches_roots_(false), 275 log_new_class_table_roots_(false), 276 intern_table_(intern_table), 277 quick_resolution_trampoline_(nullptr), 278 quick_imt_conflict_trampoline_(nullptr), 279 quick_generic_jni_trampoline_(nullptr), 280 quick_to_interpreter_bridge_trampoline_(nullptr), 281 image_pointer_size_(sizeof(void*)) { 282 CHECK(intern_table_ != nullptr); 283 static_assert(kFindArrayCacheSize == arraysize(find_array_class_cache_), 284 "Array cache size wrong."); 285 std::fill_n(find_array_class_cache_, kFindArrayCacheSize, GcRoot<mirror::Class>(nullptr)); 286} 287 288void ClassLinker::InitWithoutImage(std::vector<std::unique_ptr<const DexFile>> boot_class_path) { 289 VLOG(startup) << "ClassLinker::Init"; 290 291 Thread* const self = Thread::Current(); 292 Runtime* const runtime = Runtime::Current(); 293 gc::Heap* const heap = runtime->GetHeap(); 294 295 CHECK(!heap->HasImageSpace()) << "Runtime has image. We should use it."; 296 CHECK(!init_done_); 297 298 // Use the pointer size from the runtime since we are probably creating the image. 299 image_pointer_size_ = InstructionSetPointerSize(runtime->GetInstructionSet()); 300 301 // java_lang_Class comes first, it's needed for AllocClass 302 // The GC can't handle an object with a null class since we can't get the size of this object. 303 heap->IncrementDisableMovingGC(self); 304 StackHandleScope<64> hs(self); // 64 is picked arbitrarily. 305 auto class_class_size = mirror::Class::ClassClassSize(image_pointer_size_); 306 Handle<mirror::Class> java_lang_Class(hs.NewHandle(down_cast<mirror::Class*>( 307 heap->AllocNonMovableObject<true>(self, nullptr, class_class_size, VoidFunctor())))); 308 CHECK(java_lang_Class.Get() != nullptr); 309 mirror::Class::SetClassClass(java_lang_Class.Get()); 310 java_lang_Class->SetClass(java_lang_Class.Get()); 311 if (kUseBakerOrBrooksReadBarrier) { 312 java_lang_Class->AssertReadBarrierPointer(); 313 } 314 java_lang_Class->SetClassSize(class_class_size); 315 java_lang_Class->SetPrimitiveType(Primitive::kPrimNot); 316 heap->DecrementDisableMovingGC(self); 317 // AllocClass(mirror::Class*) can now be used 318 319 // Class[] is used for reflection support. 320 auto class_array_class_size = mirror::ObjectArray<mirror::Class>::ClassSize(image_pointer_size_); 321 Handle<mirror::Class> class_array_class(hs.NewHandle( 322 AllocClass(self, java_lang_Class.Get(), class_array_class_size))); 323 class_array_class->SetComponentType(java_lang_Class.Get()); 324 325 // java_lang_Object comes next so that object_array_class can be created. 326 Handle<mirror::Class> java_lang_Object(hs.NewHandle( 327 AllocClass(self, java_lang_Class.Get(), mirror::Object::ClassSize(image_pointer_size_)))); 328 CHECK(java_lang_Object.Get() != nullptr); 329 // backfill Object as the super class of Class. 330 java_lang_Class->SetSuperClass(java_lang_Object.Get()); 331 mirror::Class::SetStatus(java_lang_Object, mirror::Class::kStatusLoaded, self); 332 333 // Object[] next to hold class roots. 334 Handle<mirror::Class> object_array_class(hs.NewHandle( 335 AllocClass(self, java_lang_Class.Get(), 336 mirror::ObjectArray<mirror::Object>::ClassSize(image_pointer_size_)))); 337 object_array_class->SetComponentType(java_lang_Object.Get()); 338 339 // Setup the char (primitive) class to be used for char[]. 340 Handle<mirror::Class> char_class(hs.NewHandle( 341 AllocClass(self, java_lang_Class.Get(), 342 mirror::Class::PrimitiveClassSize(image_pointer_size_)))); 343 // The primitive char class won't be initialized by 344 // InitializePrimitiveClass until line 459, but strings (and 345 // internal char arrays) will be allocated before that and the 346 // component size, which is computed from the primitive type, needs 347 // to be set here. 348 char_class->SetPrimitiveType(Primitive::kPrimChar); 349 350 // Setup the char[] class to be used for String. 351 Handle<mirror::Class> char_array_class(hs.NewHandle( 352 AllocClass(self, java_lang_Class.Get(), mirror::Array::ClassSize(image_pointer_size_)))); 353 char_array_class->SetComponentType(char_class.Get()); 354 mirror::CharArray::SetArrayClass(char_array_class.Get()); 355 356 // Setup String. 357 Handle<mirror::Class> java_lang_String(hs.NewHandle( 358 AllocClass(self, java_lang_Class.Get(), mirror::String::ClassSize(image_pointer_size_)))); 359 mirror::String::SetClass(java_lang_String.Get()); 360 mirror::Class::SetStatus(java_lang_String, mirror::Class::kStatusResolved, self); 361 java_lang_String->SetStringClass(); 362 363 // Setup java.lang.ref.Reference. 364 Handle<mirror::Class> java_lang_ref_Reference(hs.NewHandle( 365 AllocClass(self, java_lang_Class.Get(), mirror::Reference::ClassSize(image_pointer_size_)))); 366 mirror::Reference::SetClass(java_lang_ref_Reference.Get()); 367 java_lang_ref_Reference->SetObjectSize(mirror::Reference::InstanceSize()); 368 mirror::Class::SetStatus(java_lang_ref_Reference, mirror::Class::kStatusResolved, self); 369 370 // Create storage for root classes, save away our work so far (requires descriptors). 371 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class>>( 372 mirror::ObjectArray<mirror::Class>::Alloc(self, object_array_class.Get(), 373 kClassRootsMax)); 374 CHECK(!class_roots_.IsNull()); 375 SetClassRoot(kJavaLangClass, java_lang_Class.Get()); 376 SetClassRoot(kJavaLangObject, java_lang_Object.Get()); 377 SetClassRoot(kClassArrayClass, class_array_class.Get()); 378 SetClassRoot(kObjectArrayClass, object_array_class.Get()); 379 SetClassRoot(kCharArrayClass, char_array_class.Get()); 380 SetClassRoot(kJavaLangString, java_lang_String.Get()); 381 SetClassRoot(kJavaLangRefReference, java_lang_ref_Reference.Get()); 382 383 // Setup the primitive type classes. 384 SetClassRoot(kPrimitiveBoolean, CreatePrimitiveClass(self, Primitive::kPrimBoolean)); 385 SetClassRoot(kPrimitiveByte, CreatePrimitiveClass(self, Primitive::kPrimByte)); 386 SetClassRoot(kPrimitiveShort, CreatePrimitiveClass(self, Primitive::kPrimShort)); 387 SetClassRoot(kPrimitiveInt, CreatePrimitiveClass(self, Primitive::kPrimInt)); 388 SetClassRoot(kPrimitiveLong, CreatePrimitiveClass(self, Primitive::kPrimLong)); 389 SetClassRoot(kPrimitiveFloat, CreatePrimitiveClass(self, Primitive::kPrimFloat)); 390 SetClassRoot(kPrimitiveDouble, CreatePrimitiveClass(self, Primitive::kPrimDouble)); 391 SetClassRoot(kPrimitiveVoid, CreatePrimitiveClass(self, Primitive::kPrimVoid)); 392 393 // Create array interface entries to populate once we can load system classes. 394 array_iftable_ = GcRoot<mirror::IfTable>(AllocIfTable(self, 2)); 395 396 // Create int array type for AllocDexCache (done in AppendToBootClassPath). 397 Handle<mirror::Class> int_array_class(hs.NewHandle( 398 AllocClass(self, java_lang_Class.Get(), mirror::Array::ClassSize(image_pointer_size_)))); 399 int_array_class->SetComponentType(GetClassRoot(kPrimitiveInt)); 400 mirror::IntArray::SetArrayClass(int_array_class.Get()); 401 SetClassRoot(kIntArrayClass, int_array_class.Get()); 402 403 // Create long array type for AllocDexCache (done in AppendToBootClassPath). 404 Handle<mirror::Class> long_array_class(hs.NewHandle( 405 AllocClass(self, java_lang_Class.Get(), mirror::Array::ClassSize(image_pointer_size_)))); 406 long_array_class->SetComponentType(GetClassRoot(kPrimitiveLong)); 407 mirror::LongArray::SetArrayClass(long_array_class.Get()); 408 SetClassRoot(kLongArrayClass, long_array_class.Get()); 409 410 // now that these are registered, we can use AllocClass() and AllocObjectArray 411 412 // Set up DexCache. This cannot be done later since AppendToBootClassPath calls AllocDexCache. 413 Handle<mirror::Class> java_lang_DexCache(hs.NewHandle( 414 AllocClass(self, java_lang_Class.Get(), mirror::DexCache::ClassSize(image_pointer_size_)))); 415 SetClassRoot(kJavaLangDexCache, java_lang_DexCache.Get()); 416 java_lang_DexCache->SetObjectSize(mirror::DexCache::InstanceSize()); 417 mirror::Class::SetStatus(java_lang_DexCache, mirror::Class::kStatusResolved, self); 418 419 // Set up array classes for string, field, method 420 Handle<mirror::Class> object_array_string(hs.NewHandle( 421 AllocClass(self, java_lang_Class.Get(), 422 mirror::ObjectArray<mirror::String>::ClassSize(image_pointer_size_)))); 423 object_array_string->SetComponentType(java_lang_String.Get()); 424 SetClassRoot(kJavaLangStringArrayClass, object_array_string.Get()); 425 426 // Create runtime resolution and imt conflict methods. 427 runtime->SetResolutionMethod(runtime->CreateResolutionMethod()); 428 runtime->SetImtConflictMethod(runtime->CreateImtConflictMethod()); 429 runtime->SetImtUnimplementedMethod(runtime->CreateImtConflictMethod()); 430 431 // Setup boot_class_path_ and register class_path now that we can use AllocObjectArray to create 432 // DexCache instances. Needs to be after String, Field, Method arrays since AllocDexCache uses 433 // these roots. 434 CHECK_NE(0U, boot_class_path.size()); 435 for (auto& dex_file : boot_class_path) { 436 CHECK(dex_file.get() != nullptr); 437 AppendToBootClassPath(self, *dex_file); 438 opened_dex_files_.push_back(std::move(dex_file)); 439 } 440 441 // now we can use FindSystemClass 442 443 // run char class through InitializePrimitiveClass to finish init 444 InitializePrimitiveClass(char_class.Get(), Primitive::kPrimChar); 445 SetClassRoot(kPrimitiveChar, char_class.Get()); // needs descriptor 446 447 // Set up GenericJNI entrypoint. That is mainly a hack for common_compiler_test.h so that 448 // we do not need friend classes or a publicly exposed setter. 449 quick_generic_jni_trampoline_ = GetQuickGenericJniStub(); 450 if (!runtime->IsAotCompiler()) { 451 // We need to set up the generic trampolines since we don't have an image. 452 quick_resolution_trampoline_ = GetQuickResolutionStub(); 453 quick_imt_conflict_trampoline_ = GetQuickImtConflictStub(); 454 quick_to_interpreter_bridge_trampoline_ = GetQuickToInterpreterBridge(); 455 } 456 457 // Object, String and DexCache need to be rerun through FindSystemClass to finish init 458 mirror::Class::SetStatus(java_lang_Object, mirror::Class::kStatusNotReady, self); 459 CHECK_EQ(java_lang_Object.Get(), FindSystemClass(self, "Ljava/lang/Object;")); 460 CHECK_EQ(java_lang_Object->GetObjectSize(), mirror::Object::InstanceSize()); 461 mirror::Class::SetStatus(java_lang_String, mirror::Class::kStatusNotReady, self); 462 mirror::Class* String_class = FindSystemClass(self, "Ljava/lang/String;"); 463 if (java_lang_String.Get() != String_class) { 464 std::ostringstream os1, os2; 465 java_lang_String->DumpClass(os1, mirror::Class::kDumpClassFullDetail); 466 String_class->DumpClass(os2, mirror::Class::kDumpClassFullDetail); 467 LOG(FATAL) << os1.str() << "\n\n" << os2.str(); 468 } 469 mirror::Class::SetStatus(java_lang_DexCache, mirror::Class::kStatusNotReady, self); 470 CHECK_EQ(java_lang_DexCache.Get(), FindSystemClass(self, "Ljava/lang/DexCache;")); 471 CHECK_EQ(java_lang_DexCache->GetObjectSize(), mirror::DexCache::InstanceSize()); 472 473 // Setup the primitive array type classes - can't be done until Object has a vtable. 474 SetClassRoot(kBooleanArrayClass, FindSystemClass(self, "[Z")); 475 mirror::BooleanArray::SetArrayClass(GetClassRoot(kBooleanArrayClass)); 476 477 SetClassRoot(kByteArrayClass, FindSystemClass(self, "[B")); 478 mirror::ByteArray::SetArrayClass(GetClassRoot(kByteArrayClass)); 479 480 CHECK_EQ(char_array_class.Get(), FindSystemClass(self, "[C")); 481 482 SetClassRoot(kShortArrayClass, FindSystemClass(self, "[S")); 483 mirror::ShortArray::SetArrayClass(GetClassRoot(kShortArrayClass)); 484 485 CHECK_EQ(int_array_class.Get(), FindSystemClass(self, "[I")); 486 487 CHECK_EQ(long_array_class.Get(), FindSystemClass(self, "[J")); 488 489 SetClassRoot(kFloatArrayClass, FindSystemClass(self, "[F")); 490 mirror::FloatArray::SetArrayClass(GetClassRoot(kFloatArrayClass)); 491 492 SetClassRoot(kDoubleArrayClass, FindSystemClass(self, "[D")); 493 mirror::DoubleArray::SetArrayClass(GetClassRoot(kDoubleArrayClass)); 494 495 CHECK_EQ(class_array_class.Get(), FindSystemClass(self, "[Ljava/lang/Class;")); 496 497 CHECK_EQ(object_array_class.Get(), FindSystemClass(self, "[Ljava/lang/Object;")); 498 499 // Setup the single, global copy of "iftable". 500 auto java_lang_Cloneable = hs.NewHandle(FindSystemClass(self, "Ljava/lang/Cloneable;")); 501 CHECK(java_lang_Cloneable.Get() != nullptr); 502 auto java_io_Serializable = hs.NewHandle(FindSystemClass(self, "Ljava/io/Serializable;")); 503 CHECK(java_io_Serializable.Get() != nullptr); 504 // We assume that Cloneable/Serializable don't have superinterfaces -- normally we'd have to 505 // crawl up and explicitly list all of the supers as well. 506 array_iftable_.Read()->SetInterface(0, java_lang_Cloneable.Get()); 507 array_iftable_.Read()->SetInterface(1, java_io_Serializable.Get()); 508 509 // Sanity check Class[] and Object[]'s interfaces. GetDirectInterface may cause thread 510 // suspension. 511 CHECK_EQ(java_lang_Cloneable.Get(), 512 mirror::Class::GetDirectInterface(self, class_array_class, 0)); 513 CHECK_EQ(java_io_Serializable.Get(), 514 mirror::Class::GetDirectInterface(self, class_array_class, 1)); 515 CHECK_EQ(java_lang_Cloneable.Get(), 516 mirror::Class::GetDirectInterface(self, object_array_class, 0)); 517 CHECK_EQ(java_io_Serializable.Get(), 518 mirror::Class::GetDirectInterface(self, object_array_class, 1)); 519 // Run Class, ArtField, and ArtMethod through FindSystemClass. This initializes their 520 // dex_cache_ fields and register them in class_table_. 521 CHECK_EQ(java_lang_Class.Get(), FindSystemClass(self, "Ljava/lang/Class;")); 522 523 CHECK_EQ(object_array_string.Get(), 524 FindSystemClass(self, GetClassRootDescriptor(kJavaLangStringArrayClass))); 525 526 // End of special init trickery, subsequent classes may be loaded via FindSystemClass. 527 528 // Create java.lang.reflect.Proxy root. 529 SetClassRoot(kJavaLangReflectProxy, FindSystemClass(self, "Ljava/lang/reflect/Proxy;")); 530 531 // Create java.lang.reflect.Field.class root. 532 auto* class_root = FindSystemClass(self, "Ljava/lang/reflect/Field;"); 533 CHECK(class_root != nullptr); 534 SetClassRoot(kJavaLangReflectField, class_root); 535 mirror::Field::SetClass(class_root); 536 537 // Create java.lang.reflect.Field array root. 538 class_root = FindSystemClass(self, "[Ljava/lang/reflect/Field;"); 539 CHECK(class_root != nullptr); 540 SetClassRoot(kJavaLangReflectFieldArrayClass, class_root); 541 mirror::Field::SetArrayClass(class_root); 542 543 // Create java.lang.reflect.Constructor.class root and array root. 544 class_root = FindSystemClass(self, "Ljava/lang/reflect/Constructor;"); 545 CHECK(class_root != nullptr); 546 SetClassRoot(kJavaLangReflectConstructor, class_root); 547 mirror::Constructor::SetClass(class_root); 548 class_root = FindSystemClass(self, "[Ljava/lang/reflect/Constructor;"); 549 CHECK(class_root != nullptr); 550 SetClassRoot(kJavaLangReflectConstructorArrayClass, class_root); 551 mirror::Constructor::SetArrayClass(class_root); 552 553 // Create java.lang.reflect.Method.class root and array root. 554 class_root = FindSystemClass(self, "Ljava/lang/reflect/Method;"); 555 CHECK(class_root != nullptr); 556 SetClassRoot(kJavaLangReflectMethod, class_root); 557 mirror::Method::SetClass(class_root); 558 class_root = FindSystemClass(self, "[Ljava/lang/reflect/Method;"); 559 CHECK(class_root != nullptr); 560 SetClassRoot(kJavaLangReflectMethodArrayClass, class_root); 561 mirror::Method::SetArrayClass(class_root); 562 563 // java.lang.ref classes need to be specially flagged, but otherwise are normal classes 564 // finish initializing Reference class 565 mirror::Class::SetStatus(java_lang_ref_Reference, mirror::Class::kStatusNotReady, self); 566 CHECK_EQ(java_lang_ref_Reference.Get(), FindSystemClass(self, "Ljava/lang/ref/Reference;")); 567 CHECK_EQ(java_lang_ref_Reference->GetObjectSize(), mirror::Reference::InstanceSize()); 568 CHECK_EQ(java_lang_ref_Reference->GetClassSize(), 569 mirror::Reference::ClassSize(image_pointer_size_)); 570 class_root = FindSystemClass(self, "Ljava/lang/ref/FinalizerReference;"); 571 class_root->SetAccessFlags(class_root->GetAccessFlags() | 572 kAccClassIsReference | kAccClassIsFinalizerReference); 573 class_root = FindSystemClass(self, "Ljava/lang/ref/PhantomReference;"); 574 class_root->SetAccessFlags(class_root->GetAccessFlags() | kAccClassIsReference | 575 kAccClassIsPhantomReference); 576 class_root = FindSystemClass(self, "Ljava/lang/ref/SoftReference;"); 577 class_root->SetAccessFlags(class_root->GetAccessFlags() | kAccClassIsReference); 578 class_root = FindSystemClass(self, "Ljava/lang/ref/WeakReference;"); 579 class_root->SetAccessFlags(class_root->GetAccessFlags() | kAccClassIsReference | 580 kAccClassIsWeakReference); 581 582 // Setup the ClassLoader, verifying the object_size_. 583 class_root = FindSystemClass(self, "Ljava/lang/ClassLoader;"); 584 CHECK_EQ(class_root->GetObjectSize(), mirror::ClassLoader::InstanceSize()); 585 SetClassRoot(kJavaLangClassLoader, class_root); 586 587 // Set up java.lang.Throwable, java.lang.ClassNotFoundException, and 588 // java.lang.StackTraceElement as a convenience. 589 SetClassRoot(kJavaLangThrowable, FindSystemClass(self, "Ljava/lang/Throwable;")); 590 mirror::Throwable::SetClass(GetClassRoot(kJavaLangThrowable)); 591 SetClassRoot(kJavaLangClassNotFoundException, 592 FindSystemClass(self, "Ljava/lang/ClassNotFoundException;")); 593 SetClassRoot(kJavaLangStackTraceElement, FindSystemClass(self, "Ljava/lang/StackTraceElement;")); 594 SetClassRoot(kJavaLangStackTraceElementArrayClass, 595 FindSystemClass(self, "[Ljava/lang/StackTraceElement;")); 596 mirror::StackTraceElement::SetClass(GetClassRoot(kJavaLangStackTraceElement)); 597 598 // Ensure void type is resolved in the core's dex cache so java.lang.Void is correctly 599 // initialized. 600 { 601 const DexFile& dex_file = java_lang_Object->GetDexFile(); 602 const DexFile::StringId* void_string_id = dex_file.FindStringId("V"); 603 CHECK(void_string_id != nullptr); 604 uint32_t void_string_index = dex_file.GetIndexForStringId(*void_string_id); 605 const DexFile::TypeId* void_type_id = dex_file.FindTypeId(void_string_index); 606 CHECK(void_type_id != nullptr); 607 uint16_t void_type_idx = dex_file.GetIndexForTypeId(*void_type_id); 608 // Now we resolve void type so the dex cache contains it. We use java.lang.Object class 609 // as referrer so the used dex cache is core's one. 610 mirror::Class* resolved_type = ResolveType(dex_file, void_type_idx, java_lang_Object.Get()); 611 CHECK_EQ(resolved_type, GetClassRoot(kPrimitiveVoid)); 612 self->AssertNoPendingException(); 613 } 614 615 FinishInit(self); 616 617 VLOG(startup) << "ClassLinker::InitFromCompiler exiting"; 618} 619 620void ClassLinker::FinishInit(Thread* self) { 621 VLOG(startup) << "ClassLinker::FinishInit entering"; 622 623 // Let the heap know some key offsets into java.lang.ref instances 624 // Note: we hard code the field indexes here rather than using FindInstanceField 625 // as the types of the field can't be resolved prior to the runtime being 626 // fully initialized 627 mirror::Class* java_lang_ref_Reference = GetClassRoot(kJavaLangRefReference); 628 mirror::Class* java_lang_ref_FinalizerReference = 629 FindSystemClass(self, "Ljava/lang/ref/FinalizerReference;"); 630 631 ArtField* pendingNext = java_lang_ref_Reference->GetInstanceField(0); 632 CHECK_STREQ(pendingNext->GetName(), "pendingNext"); 633 CHECK_STREQ(pendingNext->GetTypeDescriptor(), "Ljava/lang/ref/Reference;"); 634 635 ArtField* queue = java_lang_ref_Reference->GetInstanceField(1); 636 CHECK_STREQ(queue->GetName(), "queue"); 637 CHECK_STREQ(queue->GetTypeDescriptor(), "Ljava/lang/ref/ReferenceQueue;"); 638 639 ArtField* queueNext = java_lang_ref_Reference->GetInstanceField(2); 640 CHECK_STREQ(queueNext->GetName(), "queueNext"); 641 CHECK_STREQ(queueNext->GetTypeDescriptor(), "Ljava/lang/ref/Reference;"); 642 643 ArtField* referent = java_lang_ref_Reference->GetInstanceField(3); 644 CHECK_STREQ(referent->GetName(), "referent"); 645 CHECK_STREQ(referent->GetTypeDescriptor(), "Ljava/lang/Object;"); 646 647 ArtField* zombie = java_lang_ref_FinalizerReference->GetInstanceField(2); 648 CHECK_STREQ(zombie->GetName(), "zombie"); 649 CHECK_STREQ(zombie->GetTypeDescriptor(), "Ljava/lang/Object;"); 650 651 // ensure all class_roots_ are initialized 652 for (size_t i = 0; i < kClassRootsMax; i++) { 653 ClassRoot class_root = static_cast<ClassRoot>(i); 654 mirror::Class* klass = GetClassRoot(class_root); 655 CHECK(klass != nullptr); 656 DCHECK(klass->IsArrayClass() || klass->IsPrimitive() || klass->GetDexCache() != nullptr); 657 // note SetClassRoot does additional validation. 658 // if possible add new checks there to catch errors early 659 } 660 661 CHECK(!array_iftable_.IsNull()); 662 663 // disable the slow paths in FindClass and CreatePrimitiveClass now 664 // that Object, Class, and Object[] are setup 665 init_done_ = true; 666 667 VLOG(startup) << "ClassLinker::FinishInit exiting"; 668} 669 670void ClassLinker::RunRootClinits() { 671 Thread* self = Thread::Current(); 672 for (size_t i = 0; i < ClassLinker::kClassRootsMax; ++i) { 673 mirror::Class* c = GetClassRoot(ClassRoot(i)); 674 if (!c->IsArrayClass() && !c->IsPrimitive()) { 675 StackHandleScope<1> hs(self); 676 Handle<mirror::Class> h_class(hs.NewHandle(GetClassRoot(ClassRoot(i)))); 677 EnsureInitialized(self, h_class, true, true); 678 self->AssertNoPendingException(); 679 } 680 } 681} 682 683const OatFile* ClassLinker::RegisterOatFile(const OatFile* oat_file) { 684 WriterMutexLock mu(Thread::Current(), dex_lock_); 685 if (kIsDebugBuild) { 686 for (size_t i = 0; i < oat_files_.size(); ++i) { 687 CHECK_NE(oat_file, oat_files_[i]) << oat_file->GetLocation(); 688 } 689 } 690 VLOG(class_linker) << "Registering " << oat_file->GetLocation(); 691 oat_files_.push_back(oat_file); 692 return oat_file; 693} 694 695OatFile& ClassLinker::GetImageOatFile(gc::space::ImageSpace* space) { 696 VLOG(startup) << "ClassLinker::GetImageOatFile entering"; 697 OatFile* oat_file = space->ReleaseOatFile(); 698 CHECK_EQ(RegisterOatFile(oat_file), oat_file); 699 VLOG(startup) << "ClassLinker::GetImageOatFile exiting"; 700 return *oat_file; 701} 702 703class DexFileAndClassPair : ValueObject { 704 public: 705 DexFileAndClassPair(const DexFile* dex_file, size_t current_class_index, bool from_loaded_oat) 706 : cached_descriptor_(GetClassDescriptor(dex_file, current_class_index)), 707 dex_file_(dex_file), 708 current_class_index_(current_class_index), 709 from_loaded_oat_(from_loaded_oat) {} 710 711 DexFileAndClassPair(const DexFileAndClassPair&) = default; 712 713 DexFileAndClassPair& operator=(const DexFileAndClassPair& rhs) { 714 cached_descriptor_ = rhs.cached_descriptor_; 715 dex_file_ = rhs.dex_file_; 716 current_class_index_ = rhs.current_class_index_; 717 from_loaded_oat_ = rhs.from_loaded_oat_; 718 return *this; 719 } 720 721 const char* GetCachedDescriptor() const { 722 return cached_descriptor_; 723 } 724 725 bool operator<(const DexFileAndClassPair& rhs) const { 726 const char* lhsDescriptor = cached_descriptor_; 727 const char* rhsDescriptor = rhs.cached_descriptor_; 728 int cmp = strcmp(lhsDescriptor, rhsDescriptor); 729 if (cmp != 0) { 730 // Note that the order must be reversed. We want to iterate over the classes in dex files. 731 // They are sorted lexicographically. Thus, the priority-queue must be a min-queue. 732 return cmp > 0; 733 } 734 return dex_file_ < rhs.dex_file_; 735 } 736 737 bool DexFileHasMoreClasses() const { 738 return current_class_index_ + 1 < dex_file_->NumClassDefs(); 739 } 740 741 DexFileAndClassPair GetNext() const { 742 return DexFileAndClassPair(dex_file_, current_class_index_ + 1, from_loaded_oat_); 743 } 744 745 size_t GetCurrentClassIndex() const { 746 return current_class_index_; 747 } 748 749 bool FromLoadedOat() const { 750 return from_loaded_oat_; 751 } 752 753 const DexFile* GetDexFile() const { 754 return dex_file_; 755 } 756 757 void DeleteDexFile() { 758 delete dex_file_; 759 dex_file_ = nullptr; 760 } 761 762 private: 763 static const char* GetClassDescriptor(const DexFile* dex_file, size_t index) { 764 const DexFile::ClassDef& class_def = dex_file->GetClassDef(static_cast<uint16_t>(index)); 765 return dex_file->StringByTypeIdx(class_def.class_idx_); 766 } 767 768 const char* cached_descriptor_; 769 const DexFile* dex_file_; 770 size_t current_class_index_; 771 bool from_loaded_oat_; // We only need to compare mismatches between what we load now 772 // and what was loaded before. Any old duplicates must have been 773 // OK, and any new "internal" duplicates are as well (they must 774 // be from multidex, which resolves correctly). 775}; 776 777static void AddDexFilesFromOat(const OatFile* oat_file, bool already_loaded, 778 std::priority_queue<DexFileAndClassPair>* heap) { 779 const std::vector<const OatDexFile*>& oat_dex_files = oat_file->GetOatDexFiles(); 780 for (const OatDexFile* oat_dex_file : oat_dex_files) { 781 std::string error; 782 std::unique_ptr<const DexFile> dex_file = oat_dex_file->OpenDexFile(&error); 783 if (dex_file.get() == nullptr) { 784 LOG(WARNING) << "Could not create dex file from oat file: " << error; 785 } else { 786 if (dex_file->NumClassDefs() > 0U) { 787 heap->emplace(dex_file.release(), 0U, already_loaded); 788 } 789 } 790 } 791} 792 793static void AddNext(DexFileAndClassPair* original, 794 std::priority_queue<DexFileAndClassPair>* heap) { 795 if (original->DexFileHasMoreClasses()) { 796 heap->push(original->GetNext()); 797 } else { 798 // Need to delete the dex file. 799 original->DeleteDexFile(); 800 } 801} 802 803static void FreeDexFilesInHeap(std::priority_queue<DexFileAndClassPair>* heap) { 804 while (!heap->empty()) { 805 delete heap->top().GetDexFile(); 806 heap->pop(); 807 } 808} 809 810const OatFile* ClassLinker::GetBootOatFile() { 811 gc::space::ImageSpace* image_space = Runtime::Current()->GetHeap()->GetImageSpace(); 812 if (image_space == nullptr) { 813 return nullptr; 814 } 815 return image_space->GetOatFile(); 816} 817 818const OatFile* ClassLinker::GetPrimaryOatFile() { 819 ReaderMutexLock mu(Thread::Current(), dex_lock_); 820 const OatFile* boot_oat_file = GetBootOatFile(); 821 if (boot_oat_file != nullptr) { 822 for (const OatFile* oat_file : oat_files_) { 823 if (oat_file != boot_oat_file) { 824 return oat_file; 825 } 826 } 827 } 828 return nullptr; 829} 830 831// Check for class-def collisions in dex files. 832// 833// This works by maintaining a heap with one class from each dex file, sorted by the class 834// descriptor. Then a dex-file/class pair is continually removed from the heap and compared 835// against the following top element. If the descriptor is the same, it is now checked whether 836// the two elements agree on whether their dex file was from an already-loaded oat-file or the 837// new oat file. Any disagreement indicates a collision. 838bool ClassLinker::HasCollisions(const OatFile* oat_file, std::string* error_msg) { 839 if (!kDuplicateClassesCheck) { 840 return false; 841 } 842 843 // Dex files are registered late - once a class is actually being loaded. We have to compare 844 // against the open oat files. Take the dex_lock_ that protects oat_files_ accesses. 845 ReaderMutexLock mu(Thread::Current(), dex_lock_); 846 847 std::priority_queue<DexFileAndClassPair> queue; 848 849 // Add dex files from already loaded oat files, but skip boot. 850 { 851 const OatFile* boot_oat = GetBootOatFile(); 852 for (const OatFile* loaded_oat_file : oat_files_) { 853 if (loaded_oat_file == boot_oat) { 854 continue; 855 } 856 AddDexFilesFromOat(loaded_oat_file, true, &queue); 857 } 858 } 859 860 if (queue.empty()) { 861 // No other oat files, return early. 862 return false; 863 } 864 865 // Add dex files from the oat file to check. 866 AddDexFilesFromOat(oat_file, false, &queue); 867 868 // Now drain the queue. 869 while (!queue.empty()) { 870 DexFileAndClassPair compare_pop = queue.top(); 871 queue.pop(); 872 873 // Compare against the following elements. 874 while (!queue.empty()) { 875 DexFileAndClassPair top = queue.top(); 876 877 if (strcmp(compare_pop.GetCachedDescriptor(), top.GetCachedDescriptor()) == 0) { 878 // Same descriptor. Check whether it's crossing old-oat-files to new-oat-files. 879 if (compare_pop.FromLoadedOat() != top.FromLoadedOat()) { 880 *error_msg = 881 StringPrintf("Found duplicated class when checking oat files: '%s' in %s and %s", 882 compare_pop.GetCachedDescriptor(), 883 compare_pop.GetDexFile()->GetLocation().c_str(), 884 top.GetDexFile()->GetLocation().c_str()); 885 FreeDexFilesInHeap(&queue); 886 return true; 887 } 888 // Pop it. 889 queue.pop(); 890 AddNext(&top, &queue); 891 } else { 892 // Something else. Done here. 893 break; 894 } 895 } 896 AddNext(&compare_pop, &queue); 897 } 898 899 return false; 900} 901 902std::vector<std::unique_ptr<const DexFile>> ClassLinker::OpenDexFilesFromOat( 903 const char* dex_location, const char* oat_location, 904 std::vector<std::string>* error_msgs) { 905 CHECK(error_msgs != nullptr); 906 907 // Verify we aren't holding the mutator lock, which could starve GC if we 908 // have to generate or relocate an oat file. 909 Locks::mutator_lock_->AssertNotHeld(Thread::Current()); 910 911 OatFileAssistant oat_file_assistant(dex_location, oat_location, kRuntimeISA, 912 !Runtime::Current()->IsAotCompiler()); 913 914 // Lock the target oat location to avoid races generating and loading the 915 // oat file. 916 std::string error_msg; 917 if (!oat_file_assistant.Lock(&error_msg)) { 918 // Don't worry too much if this fails. If it does fail, it's unlikely we 919 // can generate an oat file anyway. 920 VLOG(class_linker) << "OatFileAssistant::Lock: " << error_msg; 921 } 922 923 // Check if we already have an up-to-date oat file open. 924 const OatFile* source_oat_file = nullptr; 925 { 926 ReaderMutexLock mu(Thread::Current(), dex_lock_); 927 for (const OatFile* oat_file : oat_files_) { 928 CHECK(oat_file != nullptr); 929 if (oat_file_assistant.GivenOatFileIsUpToDate(*oat_file)) { 930 source_oat_file = oat_file; 931 break; 932 } 933 } 934 } 935 936 // If we didn't have an up-to-date oat file open, try to load one from disk. 937 if (source_oat_file == nullptr) { 938 // Update the oat file on disk if we can. This may fail, but that's okay. 939 // Best effort is all that matters here. 940 if (!oat_file_assistant.MakeUpToDate(&error_msg)) { 941 LOG(WARNING) << error_msg; 942 } 943 944 // Get the oat file on disk. 945 std::unique_ptr<OatFile> oat_file = oat_file_assistant.GetBestOatFile(); 946 if (oat_file.get() != nullptr) { 947 // Take the file only if it has no collisions, or we must take it because of preopting. 948 bool accept_oat_file = !HasCollisions(oat_file.get(), &error_msg); 949 if (!accept_oat_file) { 950 // Failed the collision check. Print warning. 951 if (Runtime::Current()->IsDexFileFallbackEnabled()) { 952 LOG(WARNING) << "Found duplicate classes, falling back to interpreter mode for " 953 << dex_location; 954 } else { 955 LOG(WARNING) << "Found duplicate classes, dex-file-fallback disabled, will be failing to " 956 " load classes for " << dex_location; 957 } 958 LOG(WARNING) << error_msg; 959 960 // However, if the app was part of /system and preopted, there is no original dex file 961 // available. In that case grudgingly accept the oat file. 962 if (!DexFile::MaybeDex(dex_location)) { 963 accept_oat_file = true; 964 LOG(WARNING) << "Dex location " << dex_location << " does not seem to include dex file. " 965 << "Allow oat file use. This is potentially dangerous."; 966 } 967 } 968 969 if (accept_oat_file) { 970 source_oat_file = oat_file.release(); 971 RegisterOatFile(source_oat_file); 972 } 973 } 974 } 975 976 std::vector<std::unique_ptr<const DexFile>> dex_files; 977 978 // Load the dex files from the oat file. 979 if (source_oat_file != nullptr) { 980 dex_files = oat_file_assistant.LoadDexFiles(*source_oat_file, dex_location); 981 if (dex_files.empty()) { 982 error_msgs->push_back("Failed to open dex files from " 983 + source_oat_file->GetLocation()); 984 } 985 } 986 987 // Fall back to running out of the original dex file if we couldn't load any 988 // dex_files from the oat file. 989 if (dex_files.empty()) { 990 if (Runtime::Current()->IsDexFileFallbackEnabled()) { 991 if (!DexFile::Open(dex_location, dex_location, &error_msg, &dex_files)) { 992 LOG(WARNING) << error_msg; 993 error_msgs->push_back("Failed to open dex files from " + std::string(dex_location)); 994 } 995 } else { 996 error_msgs->push_back("Fallback mode disabled, skipping dex files."); 997 } 998 } 999 return dex_files; 1000} 1001 1002const OatFile* ClassLinker::FindOpenedOatFileFromOatLocation(const std::string& oat_location) { 1003 ReaderMutexLock mu(Thread::Current(), dex_lock_); 1004 for (size_t i = 0; i < oat_files_.size(); i++) { 1005 const OatFile* oat_file = oat_files_[i]; 1006 DCHECK(oat_file != nullptr); 1007 if (oat_file->GetLocation() == oat_location) { 1008 return oat_file; 1009 } 1010 } 1011 return nullptr; 1012} 1013 1014static void SanityCheckArtMethod(ArtMethod* m, mirror::Class* expected_class, 1015 gc::space::ImageSpace* space) 1016 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1017 if (m->IsRuntimeMethod()) { 1018 CHECK(m->GetDeclaringClass() == nullptr) << PrettyMethod(m); 1019 } else if (m->IsMiranda()) { 1020 CHECK(m->GetDeclaringClass() != nullptr) << PrettyMethod(m); 1021 } else if (expected_class != nullptr) { 1022 CHECK_EQ(m->GetDeclaringClassUnchecked(), expected_class) << PrettyMethod(m); 1023 } 1024 if (space != nullptr) { 1025 auto& header = space->GetImageHeader(); 1026 auto& methods = header.GetMethodsSection(); 1027 auto offset = reinterpret_cast<uint8_t*>(m) - space->Begin(); 1028 CHECK(methods.Contains(offset)) << m << " not in " << methods; 1029 } 1030} 1031 1032static void SanityCheckArtMethodPointerArray( 1033 mirror::PointerArray* arr, mirror::Class* expected_class, size_t pointer_size, 1034 gc::space::ImageSpace* space) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1035 CHECK(arr != nullptr); 1036 for (int32_t j = 0; j < arr->GetLength(); ++j) { 1037 auto* method = arr->GetElementPtrSize<ArtMethod*>(j, pointer_size); 1038 // expected_class == null means we are a dex cache. 1039 if (expected_class != nullptr) { 1040 CHECK(method != nullptr); 1041 } 1042 if (method != nullptr) { 1043 SanityCheckArtMethod(method, expected_class, space); 1044 } 1045 } 1046} 1047 1048static void SanityCheckObjectsCallback(mirror::Object* obj, void* arg ATTRIBUTE_UNUSED) 1049 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1050 DCHECK(obj != nullptr); 1051 CHECK(obj->GetClass() != nullptr) << "Null class in object " << obj; 1052 CHECK(obj->GetClass()->GetClass() != nullptr) << "Null class class " << obj; 1053 if (obj->IsClass()) { 1054 auto klass = obj->AsClass(); 1055 ArtField* fields[2] = { klass->GetSFields(), klass->GetIFields() }; 1056 size_t num_fields[2] = { klass->NumStaticFields(), klass->NumInstanceFields() }; 1057 for (size_t i = 0; i < 2; ++i) { 1058 for (size_t j = 0; j < num_fields[i]; ++j) { 1059 CHECK_EQ(fields[i][j].GetDeclaringClass(), klass); 1060 } 1061 } 1062 auto* runtime = Runtime::Current(); 1063 auto* image_space = runtime->GetHeap()->GetImageSpace(); 1064 auto pointer_size = runtime->GetClassLinker()->GetImagePointerSize(); 1065 for (auto& m : klass->GetDirectMethods(pointer_size)) { 1066 SanityCheckArtMethod(&m, klass, image_space); 1067 } 1068 for (auto& m : klass->GetVirtualMethods(pointer_size)) { 1069 SanityCheckArtMethod(&m, klass, image_space); 1070 } 1071 auto* vtable = klass->GetVTable(); 1072 if (vtable != nullptr) { 1073 SanityCheckArtMethodPointerArray(vtable, nullptr, pointer_size, image_space); 1074 } 1075 if (klass->ShouldHaveEmbeddedImtAndVTable()) { 1076 for (size_t i = 0; i < mirror::Class::kImtSize; ++i) { 1077 SanityCheckArtMethod(klass->GetEmbeddedImTableEntry(i, pointer_size), nullptr, image_space); 1078 } 1079 for (int32_t i = 0; i < klass->GetEmbeddedVTableLength(); ++i) { 1080 SanityCheckArtMethod(klass->GetEmbeddedVTableEntry(i, pointer_size), nullptr, image_space); 1081 } 1082 } 1083 auto* iftable = klass->GetIfTable(); 1084 if (iftable != nullptr) { 1085 for (int32_t i = 0; i < klass->GetIfTableCount(); ++i) { 1086 if (iftable->GetMethodArrayCount(i) > 0) { 1087 SanityCheckArtMethodPointerArray(iftable->GetMethodArray(i), nullptr, pointer_size, 1088 image_space); 1089 } 1090 } 1091 } 1092 } 1093} 1094 1095void ClassLinker::InitFromImage() { 1096 VLOG(startup) << "ClassLinker::InitFromImage entering"; 1097 CHECK(!init_done_); 1098 1099 Runtime* const runtime = Runtime::Current(); 1100 Thread* const self = Thread::Current(); 1101 gc::Heap* const heap = runtime->GetHeap(); 1102 gc::space::ImageSpace* const space = heap->GetImageSpace(); 1103 CHECK(space != nullptr); 1104 image_pointer_size_ = space->GetImageHeader().GetPointerSize(); 1105 dex_cache_image_class_lookup_required_ = true; 1106 OatFile& oat_file = GetImageOatFile(space); 1107 CHECK_EQ(oat_file.GetOatHeader().GetImageFileLocationOatChecksum(), 0U); 1108 CHECK_EQ(oat_file.GetOatHeader().GetImageFileLocationOatDataBegin(), 0U); 1109 const char* image_file_location = oat_file.GetOatHeader(). 1110 GetStoreValueByKey(OatHeader::kImageLocationKey); 1111 CHECK(image_file_location == nullptr || *image_file_location == 0); 1112 quick_resolution_trampoline_ = oat_file.GetOatHeader().GetQuickResolutionTrampoline(); 1113 quick_imt_conflict_trampoline_ = oat_file.GetOatHeader().GetQuickImtConflictTrampoline(); 1114 quick_generic_jni_trampoline_ = oat_file.GetOatHeader().GetQuickGenericJniTrampoline(); 1115 quick_to_interpreter_bridge_trampoline_ = oat_file.GetOatHeader().GetQuickToInterpreterBridge(); 1116 mirror::Object* dex_caches_object = space->GetImageHeader().GetImageRoot(ImageHeader::kDexCaches); 1117 mirror::ObjectArray<mirror::DexCache>* dex_caches = 1118 dex_caches_object->AsObjectArray<mirror::DexCache>(); 1119 1120 StackHandleScope<1> hs(self); 1121 Handle<mirror::ObjectArray<mirror::Class>> class_roots(hs.NewHandle( 1122 space->GetImageHeader().GetImageRoot(ImageHeader::kClassRoots)-> 1123 AsObjectArray<mirror::Class>())); 1124 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class>>(class_roots.Get()); 1125 1126 // Special case of setting up the String class early so that we can test arbitrary objects 1127 // as being Strings or not 1128 mirror::String::SetClass(GetClassRoot(kJavaLangString)); 1129 1130 CHECK_EQ(oat_file.GetOatHeader().GetDexFileCount(), 1131 static_cast<uint32_t>(dex_caches->GetLength())); 1132 for (int32_t i = 0; i < dex_caches->GetLength(); i++) { 1133 StackHandleScope<1> hs2(self); 1134 Handle<mirror::DexCache> dex_cache(hs2.NewHandle(dex_caches->Get(i))); 1135 const std::string& dex_file_location(dex_cache->GetLocation()->ToModifiedUtf8()); 1136 const OatFile::OatDexFile* oat_dex_file = oat_file.GetOatDexFile(dex_file_location.c_str(), 1137 nullptr); 1138 CHECK(oat_dex_file != nullptr) << oat_file.GetLocation() << " " << dex_file_location; 1139 std::string error_msg; 1140 std::unique_ptr<const DexFile> dex_file = oat_dex_file->OpenDexFile(&error_msg); 1141 if (dex_file.get() == nullptr) { 1142 LOG(FATAL) << "Failed to open dex file " << dex_file_location 1143 << " from within oat file " << oat_file.GetLocation() 1144 << " error '" << error_msg << "'"; 1145 UNREACHABLE(); 1146 } 1147 1148 if (kSanityCheckObjects) { 1149 SanityCheckArtMethodPointerArray(dex_cache->GetResolvedMethods(), nullptr, 1150 image_pointer_size_, space); 1151 } 1152 1153 CHECK_EQ(dex_file->GetLocationChecksum(), oat_dex_file->GetDexFileLocationChecksum()); 1154 1155 AppendToBootClassPath(*dex_file.get(), dex_cache); 1156 opened_dex_files_.push_back(std::move(dex_file)); 1157 } 1158 1159 CHECK(ValidPointerSize(image_pointer_size_)) << image_pointer_size_; 1160 1161 // Set classes on AbstractMethod early so that IsMethod tests can be performed during the live 1162 // bitmap walk. 1163 if (!runtime->IsAotCompiler()) { 1164 // Only the Aot compiler supports having an image with a different pointer size than the 1165 // runtime. This happens on the host for compile 32 bit tests since we use a 64 bit libart 1166 // compiler. We may also use 32 bit dex2oat on a system with 64 bit apps. 1167 CHECK_EQ(image_pointer_size_, sizeof(void*)); 1168 } 1169 1170 if (kSanityCheckObjects) { 1171 for (int32_t i = 0; i < dex_caches->GetLength(); i++) { 1172 auto* dex_cache = dex_caches->Get(i); 1173 for (size_t j = 0; j < dex_cache->NumResolvedFields(); ++j) { 1174 auto* field = dex_cache->GetResolvedField(j, image_pointer_size_); 1175 if (field != nullptr) { 1176 CHECK(field->GetDeclaringClass()->GetClass() != nullptr); 1177 } 1178 } 1179 } 1180 heap->VisitObjects(SanityCheckObjectsCallback, nullptr); 1181 } 1182 1183 // Set entry point to interpreter if in InterpretOnly mode. 1184 if (!runtime->IsAotCompiler() && runtime->GetInstrumentation()->InterpretOnly()) { 1185 const auto& header = space->GetImageHeader(); 1186 const auto& methods = header.GetMethodsSection(); 1187 const auto art_method_size = ArtMethod::ObjectSize(image_pointer_size_); 1188 for (uintptr_t pos = 0; pos < methods.Size(); pos += art_method_size) { 1189 auto* method = reinterpret_cast<ArtMethod*>(space->Begin() + pos + methods.Offset()); 1190 if (kIsDebugBuild && !method->IsRuntimeMethod()) { 1191 CHECK(method->GetDeclaringClass() != nullptr); 1192 } 1193 if (!method->IsNative()) { 1194 method->SetEntryPointFromInterpreterPtrSize( 1195 artInterpreterToInterpreterBridge, image_pointer_size_); 1196 if (!method->IsRuntimeMethod() && method != runtime->GetResolutionMethod()) { 1197 method->SetEntryPointFromQuickCompiledCodePtrSize(GetQuickToInterpreterBridge(), 1198 image_pointer_size_); 1199 } 1200 } 1201 } 1202 } 1203 1204 // reinit class_roots_ 1205 mirror::Class::SetClassClass(class_roots->Get(kJavaLangClass)); 1206 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class>>(class_roots.Get()); 1207 1208 // reinit array_iftable_ from any array class instance, they should be == 1209 array_iftable_ = GcRoot<mirror::IfTable>(GetClassRoot(kObjectArrayClass)->GetIfTable()); 1210 DCHECK_EQ(array_iftable_.Read(), GetClassRoot(kBooleanArrayClass)->GetIfTable()); 1211 // String class root was set above 1212 mirror::Field::SetClass(GetClassRoot(kJavaLangReflectField)); 1213 mirror::Field::SetArrayClass(GetClassRoot(kJavaLangReflectFieldArrayClass)); 1214 mirror::Constructor::SetClass(GetClassRoot(kJavaLangReflectConstructor)); 1215 mirror::Constructor::SetArrayClass(GetClassRoot(kJavaLangReflectConstructorArrayClass)); 1216 mirror::Method::SetClass(GetClassRoot(kJavaLangReflectMethod)); 1217 mirror::Method::SetArrayClass(GetClassRoot(kJavaLangReflectMethodArrayClass)); 1218 mirror::Reference::SetClass(GetClassRoot(kJavaLangRefReference)); 1219 mirror::BooleanArray::SetArrayClass(GetClassRoot(kBooleanArrayClass)); 1220 mirror::ByteArray::SetArrayClass(GetClassRoot(kByteArrayClass)); 1221 mirror::CharArray::SetArrayClass(GetClassRoot(kCharArrayClass)); 1222 mirror::DoubleArray::SetArrayClass(GetClassRoot(kDoubleArrayClass)); 1223 mirror::FloatArray::SetArrayClass(GetClassRoot(kFloatArrayClass)); 1224 mirror::IntArray::SetArrayClass(GetClassRoot(kIntArrayClass)); 1225 mirror::LongArray::SetArrayClass(GetClassRoot(kLongArrayClass)); 1226 mirror::ShortArray::SetArrayClass(GetClassRoot(kShortArrayClass)); 1227 mirror::Throwable::SetClass(GetClassRoot(kJavaLangThrowable)); 1228 mirror::StackTraceElement::SetClass(GetClassRoot(kJavaLangStackTraceElement)); 1229 1230 FinishInit(self); 1231 1232 VLOG(startup) << "ClassLinker::InitFromImage exiting"; 1233} 1234 1235bool ClassLinker::ClassInClassTable(mirror::Class* klass) { 1236 ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 1237 auto it = class_table_.Find(GcRoot<mirror::Class>(klass)); 1238 if (it == class_table_.end()) { 1239 return false; 1240 } 1241 return it->Read() == klass; 1242} 1243 1244void ClassLinker::VisitClassRoots(RootVisitor* visitor, VisitRootFlags flags) { 1245 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 1246 BufferedRootVisitor<kDefaultBufferedRootCount> buffered_visitor( 1247 visitor, RootInfo(kRootStickyClass)); 1248 if ((flags & kVisitRootFlagAllRoots) != 0) { 1249 // Argument for how root visiting deals with ArtField and ArtMethod roots. 1250 // There is 3 GC cases to handle: 1251 // Non moving concurrent: 1252 // This case is easy to handle since the reference members of ArtMethod and ArtFields are held 1253 // live by the class and class roots. In this case we probably don't even need to call 1254 // VisitNativeRoots. 1255 // 1256 // Moving non-concurrent: 1257 // This case needs to call visit VisitNativeRoots in case the classes or dex cache arrays move. 1258 // To prevent missing roots, this case needs to ensure that there is no 1259 // suspend points between the point which we allocate ArtMethod arrays and place them in a 1260 // class which is in the class table. 1261 // 1262 // Moving concurrent: 1263 // Need to make sure to not copy ArtMethods without doing read barriers since the roots are 1264 // marked concurrently and we don't hold the classlinker_classes_lock_ when we do the copy. 1265 for (GcRoot<mirror::Class>& root : class_table_) { 1266 buffered_visitor.VisitRoot(root); 1267 if ((flags & kVisitRootFlagNonMoving) == 0) { 1268 // Don't bother visiting ArtField and ArtMethod if kVisitRootFlagNonMoving is set since 1269 // these roots are all reachable from the class or dex cache. 1270 root.Read()->VisitNativeRoots(buffered_visitor, image_pointer_size_); 1271 } 1272 } 1273 // PreZygote classes can't move so we won't need to update fields' declaring classes. 1274 for (GcRoot<mirror::Class>& root : pre_zygote_class_table_) { 1275 buffered_visitor.VisitRoot(root); 1276 if ((flags & kVisitRootFlagNonMoving) == 0) { 1277 root.Read()->VisitNativeRoots(buffered_visitor, image_pointer_size_); 1278 } 1279 } 1280 } else if ((flags & kVisitRootFlagNewRoots) != 0) { 1281 for (auto& root : new_class_roots_) { 1282 mirror::Class* old_ref = root.Read<kWithoutReadBarrier>(); 1283 old_ref->VisitNativeRoots(buffered_visitor, image_pointer_size_); 1284 root.VisitRoot(visitor, RootInfo(kRootStickyClass)); 1285 mirror::Class* new_ref = root.Read<kWithoutReadBarrier>(); 1286 if (UNLIKELY(new_ref != old_ref)) { 1287 // Uh ohes, GC moved a root in the log. Need to search the class_table and update the 1288 // corresponding object. This is slow, but luckily for us, this may only happen with a 1289 // concurrent moving GC. 1290 auto it = class_table_.Find(GcRoot<mirror::Class>(old_ref)); 1291 DCHECK(it != class_table_.end()); 1292 *it = GcRoot<mirror::Class>(new_ref); 1293 } 1294 } 1295 } 1296 buffered_visitor.Flush(); // Flush before clearing new_class_roots_. 1297 if ((flags & kVisitRootFlagClearRootLog) != 0) { 1298 new_class_roots_.clear(); 1299 } 1300 if ((flags & kVisitRootFlagStartLoggingNewRoots) != 0) { 1301 log_new_class_table_roots_ = true; 1302 } else if ((flags & kVisitRootFlagStopLoggingNewRoots) != 0) { 1303 log_new_class_table_roots_ = false; 1304 } 1305 // We deliberately ignore the class roots in the image since we 1306 // handle image roots by using the MS/CMS rescanning of dirty cards. 1307} 1308 1309// Keep in sync with InitCallback. Anything we visit, we need to 1310// reinit references to when reinitializing a ClassLinker from a 1311// mapped image. 1312void ClassLinker::VisitRoots(RootVisitor* visitor, VisitRootFlags flags) { 1313 class_roots_.VisitRootIfNonNull(visitor, RootInfo(kRootVMInternal)); 1314 Thread* const self = Thread::Current(); 1315 { 1316 ReaderMutexLock mu(self, dex_lock_); 1317 if ((flags & kVisitRootFlagAllRoots) != 0) { 1318 for (GcRoot<mirror::DexCache>& dex_cache : dex_caches_) { 1319 dex_cache.VisitRoot(visitor, RootInfo(kRootVMInternal)); 1320 } 1321 } else if ((flags & kVisitRootFlagNewRoots) != 0) { 1322 for (size_t index : new_dex_cache_roots_) { 1323 dex_caches_[index].VisitRoot(visitor, RootInfo(kRootVMInternal)); 1324 } 1325 } 1326 if ((flags & kVisitRootFlagClearRootLog) != 0) { 1327 new_dex_cache_roots_.clear(); 1328 } 1329 if ((flags & kVisitRootFlagStartLoggingNewRoots) != 0) { 1330 log_new_dex_caches_roots_ = true; 1331 } else if ((flags & kVisitRootFlagStopLoggingNewRoots) != 0) { 1332 log_new_dex_caches_roots_ = false; 1333 } 1334 } 1335 VisitClassRoots(visitor, flags); 1336 array_iftable_.VisitRootIfNonNull(visitor, RootInfo(kRootVMInternal)); 1337 for (GcRoot<mirror::Class>& root : find_array_class_cache_) { 1338 root.VisitRootIfNonNull(visitor, RootInfo(kRootVMInternal)); 1339 } 1340} 1341 1342void ClassLinker::VisitClasses(ClassVisitor* visitor, void* arg) { 1343 if (dex_cache_image_class_lookup_required_) { 1344 MoveImageClassesToClassTable(); 1345 } 1346 // TODO: why isn't this a ReaderMutexLock? 1347 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 1348 for (GcRoot<mirror::Class>& root : class_table_) { 1349 if (!visitor(root.Read(), arg)) { 1350 return; 1351 } 1352 } 1353 for (GcRoot<mirror::Class>& root : pre_zygote_class_table_) { 1354 if (!visitor(root.Read(), arg)) { 1355 return; 1356 } 1357 } 1358} 1359 1360static bool GetClassesVisitorSet(mirror::Class* c, void* arg) { 1361 std::set<mirror::Class*>* classes = reinterpret_cast<std::set<mirror::Class*>*>(arg); 1362 classes->insert(c); 1363 return true; 1364} 1365 1366struct GetClassesVisitorArrayArg { 1367 Handle<mirror::ObjectArray<mirror::Class>>* classes; 1368 int32_t index; 1369 bool success; 1370}; 1371 1372static bool GetClassesVisitorArray(mirror::Class* c, void* varg) 1373 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1374 GetClassesVisitorArrayArg* arg = reinterpret_cast<GetClassesVisitorArrayArg*>(varg); 1375 if (arg->index < (*arg->classes)->GetLength()) { 1376 (*arg->classes)->Set(arg->index, c); 1377 arg->index++; 1378 return true; 1379 } else { 1380 arg->success = false; 1381 return false; 1382 } 1383} 1384 1385void ClassLinker::VisitClassesWithoutClassesLock(ClassVisitor* visitor, void* arg) { 1386 // TODO: it may be possible to avoid secondary storage if we iterate over dex caches. The problem 1387 // is avoiding duplicates. 1388 if (!kMovingClasses) { 1389 std::set<mirror::Class*> classes; 1390 VisitClasses(GetClassesVisitorSet, &classes); 1391 for (mirror::Class* klass : classes) { 1392 if (!visitor(klass, arg)) { 1393 return; 1394 } 1395 } 1396 } else { 1397 Thread* self = Thread::Current(); 1398 StackHandleScope<1> hs(self); 1399 MutableHandle<mirror::ObjectArray<mirror::Class>> classes = 1400 hs.NewHandle<mirror::ObjectArray<mirror::Class>>(nullptr); 1401 GetClassesVisitorArrayArg local_arg; 1402 local_arg.classes = &classes; 1403 local_arg.success = false; 1404 // We size the array assuming classes won't be added to the class table during the visit. 1405 // If this assumption fails we iterate again. 1406 while (!local_arg.success) { 1407 size_t class_table_size; 1408 { 1409 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 1410 class_table_size = class_table_.Size() + pre_zygote_class_table_.Size(); 1411 } 1412 mirror::Class* class_type = mirror::Class::GetJavaLangClass(); 1413 mirror::Class* array_of_class = FindArrayClass(self, &class_type); 1414 classes.Assign( 1415 mirror::ObjectArray<mirror::Class>::Alloc(self, array_of_class, class_table_size)); 1416 CHECK(classes.Get() != nullptr); // OOME. 1417 local_arg.index = 0; 1418 local_arg.success = true; 1419 VisitClasses(GetClassesVisitorArray, &local_arg); 1420 } 1421 for (int32_t i = 0; i < classes->GetLength(); ++i) { 1422 // If the class table shrank during creation of the clases array we expect null elements. If 1423 // the class table grew then the loop repeats. If classes are created after the loop has 1424 // finished then we don't visit. 1425 mirror::Class* klass = classes->Get(i); 1426 if (klass != nullptr && !visitor(klass, arg)) { 1427 return; 1428 } 1429 } 1430 } 1431} 1432 1433ClassLinker::~ClassLinker() { 1434 mirror::Class::ResetClass(); 1435 mirror::Constructor::ResetClass(); 1436 mirror::Field::ResetClass(); 1437 mirror::Method::ResetClass(); 1438 mirror::Reference::ResetClass(); 1439 mirror::StackTraceElement::ResetClass(); 1440 mirror::String::ResetClass(); 1441 mirror::Throwable::ResetClass(); 1442 mirror::BooleanArray::ResetArrayClass(); 1443 mirror::ByteArray::ResetArrayClass(); 1444 mirror::CharArray::ResetArrayClass(); 1445 mirror::Constructor::ResetArrayClass(); 1446 mirror::DoubleArray::ResetArrayClass(); 1447 mirror::Field::ResetArrayClass(); 1448 mirror::FloatArray::ResetArrayClass(); 1449 mirror::Method::ResetArrayClass(); 1450 mirror::IntArray::ResetArrayClass(); 1451 mirror::LongArray::ResetArrayClass(); 1452 mirror::ShortArray::ResetArrayClass(); 1453 STLDeleteElements(&oat_files_); 1454} 1455 1456mirror::PointerArray* ClassLinker::AllocPointerArray(Thread* self, size_t length) { 1457 return down_cast<mirror::PointerArray*>(image_pointer_size_ == 8u ? 1458 static_cast<mirror::Array*>(mirror::LongArray::Alloc(self, length)) : 1459 static_cast<mirror::Array*>(mirror::IntArray::Alloc(self, length))); 1460} 1461 1462mirror::DexCache* ClassLinker::AllocDexCache(Thread* self, const DexFile& dex_file) { 1463 StackHandleScope<6> hs(self); 1464 auto dex_cache(hs.NewHandle(down_cast<mirror::DexCache*>( 1465 GetClassRoot(kJavaLangDexCache)->AllocObject(self)))); 1466 if (dex_cache.Get() == nullptr) { 1467 self->AssertPendingOOMException(); 1468 return nullptr; 1469 } 1470 auto location(hs.NewHandle(intern_table_->InternStrong(dex_file.GetLocation().c_str()))); 1471 if (location.Get() == nullptr) { 1472 self->AssertPendingOOMException(); 1473 return nullptr; 1474 } 1475 auto strings(hs.NewHandle(AllocStringArray(self, dex_file.NumStringIds()))); 1476 if (strings.Get() == nullptr) { 1477 self->AssertPendingOOMException(); 1478 return nullptr; 1479 } 1480 auto types(hs.NewHandle(AllocClassArray(self, dex_file.NumTypeIds()))); 1481 if (types.Get() == nullptr) { 1482 self->AssertPendingOOMException(); 1483 return nullptr; 1484 } 1485 auto methods(hs.NewHandle(AllocPointerArray(self, dex_file.NumMethodIds()))); 1486 if (methods.Get() == nullptr) { 1487 self->AssertPendingOOMException(); 1488 return nullptr; 1489 } 1490 auto fields(hs.NewHandle(AllocPointerArray(self, dex_file.NumFieldIds()))); 1491 if (fields.Get() == nullptr) { 1492 self->AssertPendingOOMException(); 1493 return nullptr; 1494 } 1495 dex_cache->Init(&dex_file, location.Get(), strings.Get(), types.Get(), methods.Get(), 1496 fields.Get(), image_pointer_size_); 1497 return dex_cache.Get(); 1498} 1499 1500mirror::Class* ClassLinker::AllocClass(Thread* self, mirror::Class* java_lang_Class, 1501 uint32_t class_size) { 1502 DCHECK_GE(class_size, sizeof(mirror::Class)); 1503 gc::Heap* heap = Runtime::Current()->GetHeap(); 1504 mirror::Class::InitializeClassVisitor visitor(class_size); 1505 mirror::Object* k = kMovingClasses ? 1506 heap->AllocObject<true>(self, java_lang_Class, class_size, visitor) : 1507 heap->AllocNonMovableObject<true>(self, java_lang_Class, class_size, visitor); 1508 if (UNLIKELY(k == nullptr)) { 1509 self->AssertPendingOOMException(); 1510 return nullptr; 1511 } 1512 return k->AsClass(); 1513} 1514 1515mirror::Class* ClassLinker::AllocClass(Thread* self, uint32_t class_size) { 1516 return AllocClass(self, GetClassRoot(kJavaLangClass), class_size); 1517} 1518 1519mirror::ObjectArray<mirror::StackTraceElement>* ClassLinker::AllocStackTraceElementArray( 1520 Thread* self, size_t length) { 1521 return mirror::ObjectArray<mirror::StackTraceElement>::Alloc( 1522 self, GetClassRoot(kJavaLangStackTraceElementArrayClass), length); 1523} 1524 1525mirror::Class* ClassLinker::EnsureResolved(Thread* self, const char* descriptor, 1526 mirror::Class* klass) { 1527 DCHECK(klass != nullptr); 1528 1529 // For temporary classes we must wait for them to be retired. 1530 if (init_done_ && klass->IsTemp()) { 1531 CHECK(!klass->IsResolved()); 1532 if (klass->IsErroneous()) { 1533 ThrowEarlierClassFailure(klass); 1534 return nullptr; 1535 } 1536 StackHandleScope<1> hs(self); 1537 Handle<mirror::Class> h_class(hs.NewHandle(klass)); 1538 ObjectLock<mirror::Class> lock(self, h_class); 1539 // Loop and wait for the resolving thread to retire this class. 1540 while (!h_class->IsRetired() && !h_class->IsErroneous()) { 1541 lock.WaitIgnoringInterrupts(); 1542 } 1543 if (h_class->IsErroneous()) { 1544 ThrowEarlierClassFailure(h_class.Get()); 1545 return nullptr; 1546 } 1547 CHECK(h_class->IsRetired()); 1548 // Get the updated class from class table. 1549 klass = LookupClass(self, descriptor, ComputeModifiedUtf8Hash(descriptor), 1550 h_class.Get()->GetClassLoader()); 1551 } 1552 1553 // Wait for the class if it has not already been linked. 1554 if (!klass->IsResolved() && !klass->IsErroneous()) { 1555 StackHandleScope<1> hs(self); 1556 HandleWrapper<mirror::Class> h_class(hs.NewHandleWrapper(&klass)); 1557 ObjectLock<mirror::Class> lock(self, h_class); 1558 // Check for circular dependencies between classes. 1559 if (!h_class->IsResolved() && h_class->GetClinitThreadId() == self->GetTid()) { 1560 ThrowClassCircularityError(h_class.Get()); 1561 mirror::Class::SetStatus(h_class, mirror::Class::kStatusError, self); 1562 return nullptr; 1563 } 1564 // Wait for the pending initialization to complete. 1565 while (!h_class->IsResolved() && !h_class->IsErroneous()) { 1566 lock.WaitIgnoringInterrupts(); 1567 } 1568 } 1569 1570 if (klass->IsErroneous()) { 1571 ThrowEarlierClassFailure(klass); 1572 return nullptr; 1573 } 1574 // Return the loaded class. No exceptions should be pending. 1575 CHECK(klass->IsResolved()) << PrettyClass(klass); 1576 self->AssertNoPendingException(); 1577 return klass; 1578} 1579 1580typedef std::pair<const DexFile*, const DexFile::ClassDef*> ClassPathEntry; 1581 1582// Search a collection of DexFiles for a descriptor 1583ClassPathEntry FindInClassPath(const char* descriptor, 1584 size_t hash, const std::vector<const DexFile*>& class_path) { 1585 for (const DexFile* dex_file : class_path) { 1586 const DexFile::ClassDef* dex_class_def = dex_file->FindClassDef(descriptor, hash); 1587 if (dex_class_def != nullptr) { 1588 return ClassPathEntry(dex_file, dex_class_def); 1589 } 1590 } 1591 return ClassPathEntry(nullptr, nullptr); 1592} 1593 1594static bool IsBootClassLoader(ScopedObjectAccessAlreadyRunnable& soa, 1595 mirror::ClassLoader* class_loader) 1596 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1597 return class_loader == nullptr || 1598 class_loader->GetClass() == 1599 soa.Decode<mirror::Class*>(WellKnownClasses::java_lang_BootClassLoader); 1600} 1601 1602bool ClassLinker::FindClassInPathClassLoader(ScopedObjectAccessAlreadyRunnable& soa, 1603 Thread* self, const char* descriptor, 1604 size_t hash, 1605 Handle<mirror::ClassLoader> class_loader, 1606 mirror::Class** result) { 1607 // Termination case: boot class-loader. 1608 if (IsBootClassLoader(soa, class_loader.Get())) { 1609 // The boot class loader, search the boot class path. 1610 ClassPathEntry pair = FindInClassPath(descriptor, hash, boot_class_path_); 1611 if (pair.second != nullptr) { 1612 mirror::Class* klass = LookupClass(self, descriptor, hash, nullptr); 1613 if (klass != nullptr) { 1614 *result = EnsureResolved(self, descriptor, klass); 1615 } else { 1616 *result = DefineClass(self, descriptor, hash, NullHandle<mirror::ClassLoader>(), 1617 *pair.first, *pair.second); 1618 } 1619 if (*result == nullptr) { 1620 CHECK(self->IsExceptionPending()) << descriptor; 1621 self->ClearException(); 1622 } 1623 } else { 1624 *result = nullptr; 1625 } 1626 return true; 1627 } 1628 1629 // Unsupported class-loader? 1630 if (class_loader->GetClass() != 1631 soa.Decode<mirror::Class*>(WellKnownClasses::dalvik_system_PathClassLoader)) { 1632 *result = nullptr; 1633 return false; 1634 } 1635 1636 // Handles as RegisterDexFile may allocate dex caches (and cause thread suspension). 1637 StackHandleScope<4> hs(self); 1638 Handle<mirror::ClassLoader> h_parent(hs.NewHandle(class_loader->GetParent())); 1639 bool recursive_result = FindClassInPathClassLoader(soa, self, descriptor, hash, h_parent, result); 1640 1641 if (!recursive_result) { 1642 // Something wrong up the chain. 1643 return false; 1644 } 1645 1646 if (*result != nullptr) { 1647 // Found the class up the chain. 1648 return true; 1649 } 1650 1651 // Handle this step. 1652 // Handle as if this is the child PathClassLoader. 1653 // The class loader is a PathClassLoader which inherits from BaseDexClassLoader. 1654 // We need to get the DexPathList and loop through it. 1655 ArtField* const cookie_field = soa.DecodeField(WellKnownClasses::dalvik_system_DexFile_cookie); 1656 ArtField* const dex_file_field = 1657 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList__Element_dexFile); 1658 mirror::Object* dex_path_list = 1659 soa.DecodeField(WellKnownClasses::dalvik_system_PathClassLoader_pathList)-> 1660 GetObject(class_loader.Get()); 1661 if (dex_path_list != nullptr && dex_file_field != nullptr && cookie_field != nullptr) { 1662 // DexPathList has an array dexElements of Elements[] which each contain a dex file. 1663 mirror::Object* dex_elements_obj = 1664 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList_dexElements)-> 1665 GetObject(dex_path_list); 1666 // Loop through each dalvik.system.DexPathList$Element's dalvik.system.DexFile and look 1667 // at the mCookie which is a DexFile vector. 1668 if (dex_elements_obj != nullptr) { 1669 Handle<mirror::ObjectArray<mirror::Object>> dex_elements = 1670 hs.NewHandle(dex_elements_obj->AsObjectArray<mirror::Object>()); 1671 for (int32_t i = 0; i < dex_elements->GetLength(); ++i) { 1672 mirror::Object* element = dex_elements->GetWithoutChecks(i); 1673 if (element == nullptr) { 1674 // Should never happen, fall back to java code to throw a NPE. 1675 break; 1676 } 1677 mirror::Object* dex_file = dex_file_field->GetObject(element); 1678 if (dex_file != nullptr) { 1679 mirror::LongArray* long_array = cookie_field->GetObject(dex_file)->AsLongArray(); 1680 if (long_array == nullptr) { 1681 // This should never happen so log a warning. 1682 LOG(WARNING) << "Null DexFile::mCookie for " << descriptor; 1683 break; 1684 } 1685 int32_t long_array_size = long_array->GetLength(); 1686 for (int32_t j = 0; j < long_array_size; ++j) { 1687 const DexFile* cp_dex_file = reinterpret_cast<const DexFile*>(static_cast<uintptr_t>( 1688 long_array->GetWithoutChecks(j))); 1689 const DexFile::ClassDef* dex_class_def = cp_dex_file->FindClassDef(descriptor, hash); 1690 if (dex_class_def != nullptr) { 1691 RegisterDexFile(*cp_dex_file); 1692 mirror::Class* klass = DefineClass(self, descriptor, hash, class_loader, 1693 *cp_dex_file, *dex_class_def); 1694 if (klass == nullptr) { 1695 CHECK(self->IsExceptionPending()) << descriptor; 1696 self->ClearException(); 1697 // TODO: Is it really right to break here, and not check the other dex files? 1698 return true; 1699 } 1700 *result = klass; 1701 return true; 1702 } 1703 } 1704 } 1705 } 1706 } 1707 self->AssertNoPendingException(); 1708 } 1709 1710 // Result is still null from the parent call, no need to set it again... 1711 return true; 1712} 1713 1714mirror::Class* ClassLinker::FindClass(Thread* self, const char* descriptor, 1715 Handle<mirror::ClassLoader> class_loader) { 1716 DCHECK_NE(*descriptor, '\0') << "descriptor is empty string"; 1717 DCHECK(self != nullptr); 1718 self->AssertNoPendingException(); 1719 if (descriptor[1] == '\0') { 1720 // only the descriptors of primitive types should be 1 character long, also avoid class lookup 1721 // for primitive classes that aren't backed by dex files. 1722 return FindPrimitiveClass(descriptor[0]); 1723 } 1724 const size_t hash = ComputeModifiedUtf8Hash(descriptor); 1725 // Find the class in the loaded classes table. 1726 mirror::Class* klass = LookupClass(self, descriptor, hash, class_loader.Get()); 1727 if (klass != nullptr) { 1728 return EnsureResolved(self, descriptor, klass); 1729 } 1730 // Class is not yet loaded. 1731 if (descriptor[0] == '[') { 1732 return CreateArrayClass(self, descriptor, hash, class_loader); 1733 } else if (class_loader.Get() == nullptr) { 1734 // The boot class loader, search the boot class path. 1735 ClassPathEntry pair = FindInClassPath(descriptor, hash, boot_class_path_); 1736 if (pair.second != nullptr) { 1737 return DefineClass(self, descriptor, hash, NullHandle<mirror::ClassLoader>(), *pair.first, 1738 *pair.second); 1739 } else { 1740 // The boot class loader is searched ahead of the application class loader, failures are 1741 // expected and will be wrapped in a ClassNotFoundException. Use the pre-allocated error to 1742 // trigger the chaining with a proper stack trace. 1743 mirror::Throwable* pre_allocated = Runtime::Current()->GetPreAllocatedNoClassDefFoundError(); 1744 self->SetException(pre_allocated); 1745 return nullptr; 1746 } 1747 } else { 1748 ScopedObjectAccessUnchecked soa(self); 1749 mirror::Class* cp_klass; 1750 if (FindClassInPathClassLoader(soa, self, descriptor, hash, class_loader, &cp_klass)) { 1751 // The chain was understood. So the value in cp_klass is either the class we were looking 1752 // for, or not found. 1753 if (cp_klass != nullptr) { 1754 return cp_klass; 1755 } 1756 // TODO: We handle the boot classpath loader in FindClassInPathClassLoader. Try to unify this 1757 // and the branch above. TODO: throw the right exception here. 1758 1759 // We'll let the Java-side rediscover all this and throw the exception with the right stack 1760 // trace. 1761 } 1762 1763 if (Runtime::Current()->IsAotCompiler()) { 1764 // Oops, compile-time, can't run actual class-loader code. 1765 mirror::Throwable* pre_allocated = Runtime::Current()->GetPreAllocatedNoClassDefFoundError(); 1766 self->SetException(pre_allocated); 1767 return nullptr; 1768 } 1769 1770 ScopedLocalRef<jobject> class_loader_object(soa.Env(), 1771 soa.AddLocalReference<jobject>(class_loader.Get())); 1772 std::string class_name_string(DescriptorToDot(descriptor)); 1773 ScopedLocalRef<jobject> result(soa.Env(), nullptr); 1774 { 1775 ScopedThreadStateChange tsc(self, kNative); 1776 ScopedLocalRef<jobject> class_name_object(soa.Env(), 1777 soa.Env()->NewStringUTF(class_name_string.c_str())); 1778 if (class_name_object.get() == nullptr) { 1779 DCHECK(self->IsExceptionPending()); // OOME. 1780 return nullptr; 1781 } 1782 CHECK(class_loader_object.get() != nullptr); 1783 result.reset(soa.Env()->CallObjectMethod(class_loader_object.get(), 1784 WellKnownClasses::java_lang_ClassLoader_loadClass, 1785 class_name_object.get())); 1786 } 1787 if (self->IsExceptionPending()) { 1788 // If the ClassLoader threw, pass that exception up. 1789 return nullptr; 1790 } else if (result.get() == nullptr) { 1791 // broken loader - throw NPE to be compatible with Dalvik 1792 ThrowNullPointerException(StringPrintf("ClassLoader.loadClass returned null for %s", 1793 class_name_string.c_str()).c_str()); 1794 return nullptr; 1795 } else { 1796 // success, return mirror::Class* 1797 return soa.Decode<mirror::Class*>(result.get()); 1798 } 1799 } 1800 UNREACHABLE(); 1801} 1802 1803mirror::Class* ClassLinker::DefineClass(Thread* self, const char* descriptor, size_t hash, 1804 Handle<mirror::ClassLoader> class_loader, 1805 const DexFile& dex_file, 1806 const DexFile::ClassDef& dex_class_def) { 1807 StackHandleScope<3> hs(self); 1808 auto klass = hs.NewHandle<mirror::Class>(nullptr); 1809 1810 // Load the class from the dex file. 1811 if (UNLIKELY(!init_done_)) { 1812 // finish up init of hand crafted class_roots_ 1813 if (strcmp(descriptor, "Ljava/lang/Object;") == 0) { 1814 klass.Assign(GetClassRoot(kJavaLangObject)); 1815 } else if (strcmp(descriptor, "Ljava/lang/Class;") == 0) { 1816 klass.Assign(GetClassRoot(kJavaLangClass)); 1817 } else if (strcmp(descriptor, "Ljava/lang/String;") == 0) { 1818 klass.Assign(GetClassRoot(kJavaLangString)); 1819 } else if (strcmp(descriptor, "Ljava/lang/ref/Reference;") == 0) { 1820 klass.Assign(GetClassRoot(kJavaLangRefReference)); 1821 } else if (strcmp(descriptor, "Ljava/lang/DexCache;") == 0) { 1822 klass.Assign(GetClassRoot(kJavaLangDexCache)); 1823 } 1824 } 1825 1826 if (klass.Get() == nullptr) { 1827 // Allocate a class with the status of not ready. 1828 // Interface object should get the right size here. Regular class will 1829 // figure out the right size later and be replaced with one of the right 1830 // size when the class becomes resolved. 1831 klass.Assign(AllocClass(self, SizeOfClassWithoutEmbeddedTables(dex_file, dex_class_def))); 1832 } 1833 if (UNLIKELY(klass.Get() == nullptr)) { 1834 CHECK(self->IsExceptionPending()); // Expect an OOME. 1835 return nullptr; 1836 } 1837 klass->SetDexCache(FindDexCache(dex_file)); 1838 1839 SetupClass(dex_file, dex_class_def, klass, class_loader.Get()); 1840 1841 // Mark the string class by setting its access flag. 1842 if (UNLIKELY(!init_done_)) { 1843 if (strcmp(descriptor, "Ljava/lang/String;") == 0) { 1844 klass->SetStringClass(); 1845 } 1846 } 1847 1848 ObjectLock<mirror::Class> lock(self, klass); 1849 klass->SetClinitThreadId(self->GetTid()); 1850 1851 // Add the newly loaded class to the loaded classes table. 1852 mirror::Class* existing = InsertClass(descriptor, klass.Get(), hash); 1853 if (existing != nullptr) { 1854 // We failed to insert because we raced with another thread. Calling EnsureResolved may cause 1855 // this thread to block. 1856 return EnsureResolved(self, descriptor, existing); 1857 } 1858 1859 // Load the fields and other things after we are inserted in the table. This is so that we don't 1860 // end up allocating unfree-able linear alloc resources and then lose the race condition. The 1861 // other reason is that the field roots are only visited from the class table. So we need to be 1862 // inserted before we allocate / fill in these fields. 1863 LoadClass(self, dex_file, dex_class_def, klass); 1864 if (self->IsExceptionPending()) { 1865 // An exception occured during load, set status to erroneous while holding klass' lock in case 1866 // notification is necessary. 1867 if (!klass->IsErroneous()) { 1868 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 1869 } 1870 return nullptr; 1871 } 1872 1873 // Finish loading (if necessary) by finding parents 1874 CHECK(!klass->IsLoaded()); 1875 if (!LoadSuperAndInterfaces(klass, dex_file)) { 1876 // Loading failed. 1877 if (!klass->IsErroneous()) { 1878 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 1879 } 1880 return nullptr; 1881 } 1882 CHECK(klass->IsLoaded()); 1883 // Link the class (if necessary) 1884 CHECK(!klass->IsResolved()); 1885 // TODO: Use fast jobjects? 1886 auto interfaces = hs.NewHandle<mirror::ObjectArray<mirror::Class>>(nullptr); 1887 1888 MutableHandle<mirror::Class> h_new_class = hs.NewHandle<mirror::Class>(nullptr); 1889 if (!LinkClass(self, descriptor, klass, interfaces, &h_new_class)) { 1890 // Linking failed. 1891 if (!klass->IsErroneous()) { 1892 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 1893 } 1894 return nullptr; 1895 } 1896 self->AssertNoPendingException(); 1897 CHECK(h_new_class.Get() != nullptr) << descriptor; 1898 CHECK(h_new_class->IsResolved()) << descriptor; 1899 1900 // Instrumentation may have updated entrypoints for all methods of all 1901 // classes. However it could not update methods of this class while we 1902 // were loading it. Now the class is resolved, we can update entrypoints 1903 // as required by instrumentation. 1904 if (Runtime::Current()->GetInstrumentation()->AreExitStubsInstalled()) { 1905 // We must be in the kRunnable state to prevent instrumentation from 1906 // suspending all threads to update entrypoints while we are doing it 1907 // for this class. 1908 DCHECK_EQ(self->GetState(), kRunnable); 1909 Runtime::Current()->GetInstrumentation()->InstallStubsForClass(h_new_class.Get()); 1910 } 1911 1912 /* 1913 * We send CLASS_PREPARE events to the debugger from here. The 1914 * definition of "preparation" is creating the static fields for a 1915 * class and initializing them to the standard default values, but not 1916 * executing any code (that comes later, during "initialization"). 1917 * 1918 * We did the static preparation in LinkClass. 1919 * 1920 * The class has been prepared and resolved but possibly not yet verified 1921 * at this point. 1922 */ 1923 Dbg::PostClassPrepare(h_new_class.Get()); 1924 1925 return h_new_class.Get(); 1926} 1927 1928uint32_t ClassLinker::SizeOfClassWithoutEmbeddedTables(const DexFile& dex_file, 1929 const DexFile::ClassDef& dex_class_def) { 1930 const uint8_t* class_data = dex_file.GetClassData(dex_class_def); 1931 size_t num_ref = 0; 1932 size_t num_8 = 0; 1933 size_t num_16 = 0; 1934 size_t num_32 = 0; 1935 size_t num_64 = 0; 1936 if (class_data != nullptr) { 1937 for (ClassDataItemIterator it(dex_file, class_data); it.HasNextStaticField(); it.Next()) { 1938 const DexFile::FieldId& field_id = dex_file.GetFieldId(it.GetMemberIndex()); 1939 const char* descriptor = dex_file.GetFieldTypeDescriptor(field_id); 1940 char c = descriptor[0]; 1941 switch (c) { 1942 case 'L': 1943 case '[': 1944 num_ref++; 1945 break; 1946 case 'J': 1947 case 'D': 1948 num_64++; 1949 break; 1950 case 'I': 1951 case 'F': 1952 num_32++; 1953 break; 1954 case 'S': 1955 case 'C': 1956 num_16++; 1957 break; 1958 case 'B': 1959 case 'Z': 1960 num_8++; 1961 break; 1962 default: 1963 LOG(FATAL) << "Unknown descriptor: " << c; 1964 UNREACHABLE(); 1965 } 1966 } 1967 } 1968 return mirror::Class::ComputeClassSize(false, 0, num_8, num_16, num_32, num_64, num_ref, 1969 image_pointer_size_); 1970} 1971 1972OatFile::OatClass ClassLinker::FindOatClass(const DexFile& dex_file, uint16_t class_def_idx, 1973 bool* found) { 1974 DCHECK_NE(class_def_idx, DexFile::kDexNoIndex16); 1975 const OatFile::OatDexFile* oat_dex_file = dex_file.GetOatDexFile(); 1976 if (oat_dex_file == nullptr) { 1977 *found = false; 1978 return OatFile::OatClass::Invalid(); 1979 } 1980 *found = true; 1981 return oat_dex_file->GetOatClass(class_def_idx); 1982} 1983 1984static uint32_t GetOatMethodIndexFromMethodIndex(const DexFile& dex_file, uint16_t class_def_idx, 1985 uint32_t method_idx) { 1986 const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_idx); 1987 const uint8_t* class_data = dex_file.GetClassData(class_def); 1988 CHECK(class_data != nullptr); 1989 ClassDataItemIterator it(dex_file, class_data); 1990 // Skip fields 1991 while (it.HasNextStaticField()) { 1992 it.Next(); 1993 } 1994 while (it.HasNextInstanceField()) { 1995 it.Next(); 1996 } 1997 // Process methods 1998 size_t class_def_method_index = 0; 1999 while (it.HasNextDirectMethod()) { 2000 if (it.GetMemberIndex() == method_idx) { 2001 return class_def_method_index; 2002 } 2003 class_def_method_index++; 2004 it.Next(); 2005 } 2006 while (it.HasNextVirtualMethod()) { 2007 if (it.GetMemberIndex() == method_idx) { 2008 return class_def_method_index; 2009 } 2010 class_def_method_index++; 2011 it.Next(); 2012 } 2013 DCHECK(!it.HasNext()); 2014 LOG(FATAL) << "Failed to find method index " << method_idx << " in " << dex_file.GetLocation(); 2015 UNREACHABLE(); 2016} 2017 2018const OatFile::OatMethod ClassLinker::FindOatMethodFor(ArtMethod* method, bool* found) { 2019 // Although we overwrite the trampoline of non-static methods, we may get here via the resolution 2020 // method for direct methods (or virtual methods made direct). 2021 mirror::Class* declaring_class = method->GetDeclaringClass(); 2022 size_t oat_method_index; 2023 if (method->IsStatic() || method->IsDirect()) { 2024 // Simple case where the oat method index was stashed at load time. 2025 oat_method_index = method->GetMethodIndex(); 2026 } else { 2027 // We're invoking a virtual method directly (thanks to sharpening), compute the oat_method_index 2028 // by search for its position in the declared virtual methods. 2029 oat_method_index = declaring_class->NumDirectMethods(); 2030 size_t end = declaring_class->NumVirtualMethods(); 2031 bool found_virtual = false; 2032 for (size_t i = 0; i < end; i++) { 2033 // Check method index instead of identity in case of duplicate method definitions. 2034 if (method->GetDexMethodIndex() == 2035 declaring_class->GetVirtualMethod(i, image_pointer_size_)->GetDexMethodIndex()) { 2036 found_virtual = true; 2037 break; 2038 } 2039 oat_method_index++; 2040 } 2041 CHECK(found_virtual) << "Didn't find oat method index for virtual method: " 2042 << PrettyMethod(method); 2043 } 2044 DCHECK_EQ(oat_method_index, 2045 GetOatMethodIndexFromMethodIndex(*declaring_class->GetDexCache()->GetDexFile(), 2046 method->GetDeclaringClass()->GetDexClassDefIndex(), 2047 method->GetDexMethodIndex())); 2048 OatFile::OatClass oat_class = FindOatClass(*declaring_class->GetDexCache()->GetDexFile(), 2049 declaring_class->GetDexClassDefIndex(), 2050 found); 2051 if (!(*found)) { 2052 return OatFile::OatMethod::Invalid(); 2053 } 2054 return oat_class.GetOatMethod(oat_method_index); 2055} 2056 2057// Special case to get oat code without overwriting a trampoline. 2058const void* ClassLinker::GetQuickOatCodeFor(ArtMethod* method) { 2059 CHECK(!method->IsAbstract()) << PrettyMethod(method); 2060 if (method->IsProxyMethod()) { 2061 return GetQuickProxyInvokeHandler(); 2062 } 2063 bool found; 2064 OatFile::OatMethod oat_method = FindOatMethodFor(method, &found); 2065 if (found) { 2066 auto* code = oat_method.GetQuickCode(); 2067 if (code != nullptr) { 2068 return code; 2069 } 2070 } 2071 jit::Jit* const jit = Runtime::Current()->GetJit(); 2072 if (jit != nullptr) { 2073 auto* code = jit->GetCodeCache()->GetCodeFor(method); 2074 if (code != nullptr) { 2075 return code; 2076 } 2077 } 2078 if (method->IsNative()) { 2079 // No code and native? Use generic trampoline. 2080 return GetQuickGenericJniStub(); 2081 } 2082 return GetQuickToInterpreterBridge(); 2083} 2084 2085const void* ClassLinker::GetOatMethodQuickCodeFor(ArtMethod* method) { 2086 if (method->IsNative() || method->IsAbstract() || method->IsProxyMethod()) { 2087 return nullptr; 2088 } 2089 bool found; 2090 OatFile::OatMethod oat_method = FindOatMethodFor(method, &found); 2091 if (found) { 2092 return oat_method.GetQuickCode(); 2093 } 2094 jit::Jit* jit = Runtime::Current()->GetJit(); 2095 if (jit != nullptr) { 2096 auto* code = jit->GetCodeCache()->GetCodeFor(method); 2097 if (code != nullptr) { 2098 return code; 2099 } 2100 } 2101 return nullptr; 2102} 2103 2104const void* ClassLinker::GetQuickOatCodeFor(const DexFile& dex_file, uint16_t class_def_idx, 2105 uint32_t method_idx) { 2106 bool found; 2107 OatFile::OatClass oat_class = FindOatClass(dex_file, class_def_idx, &found); 2108 if (!found) { 2109 return nullptr; 2110 } 2111 uint32_t oat_method_idx = GetOatMethodIndexFromMethodIndex(dex_file, class_def_idx, method_idx); 2112 return oat_class.GetOatMethod(oat_method_idx).GetQuickCode(); 2113} 2114 2115// Returns true if the method must run with interpreter, false otherwise. 2116static bool NeedsInterpreter(ArtMethod* method, const void* quick_code) 2117 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 2118 if (quick_code == nullptr) { 2119 // No code: need interpreter. 2120 // May return true for native code, in the case of generic JNI 2121 // DCHECK(!method->IsNative()); 2122 return true; 2123 } 2124 // If interpreter mode is enabled, every method (except native and proxy) must 2125 // be run with interpreter. 2126 return Runtime::Current()->GetInstrumentation()->InterpretOnly() && 2127 !method->IsNative() && !method->IsProxyMethod(); 2128} 2129 2130void ClassLinker::FixupStaticTrampolines(mirror::Class* klass) { 2131 DCHECK(klass->IsInitialized()) << PrettyDescriptor(klass); 2132 if (klass->NumDirectMethods() == 0) { 2133 return; // No direct methods => no static methods. 2134 } 2135 Runtime* runtime = Runtime::Current(); 2136 if (!runtime->IsStarted()) { 2137 if (runtime->IsAotCompiler() || runtime->GetHeap()->HasImageSpace()) { 2138 return; // OAT file unavailable. 2139 } 2140 } 2141 2142 const DexFile& dex_file = klass->GetDexFile(); 2143 const DexFile::ClassDef* dex_class_def = klass->GetClassDef(); 2144 CHECK(dex_class_def != nullptr); 2145 const uint8_t* class_data = dex_file.GetClassData(*dex_class_def); 2146 // There should always be class data if there were direct methods. 2147 CHECK(class_data != nullptr) << PrettyDescriptor(klass); 2148 ClassDataItemIterator it(dex_file, class_data); 2149 // Skip fields 2150 while (it.HasNextStaticField()) { 2151 it.Next(); 2152 } 2153 while (it.HasNextInstanceField()) { 2154 it.Next(); 2155 } 2156 bool has_oat_class; 2157 OatFile::OatClass oat_class = FindOatClass(dex_file, klass->GetDexClassDefIndex(), 2158 &has_oat_class); 2159 // Link the code of methods skipped by LinkCode. 2160 for (size_t method_index = 0; it.HasNextDirectMethod(); ++method_index, it.Next()) { 2161 ArtMethod* method = klass->GetDirectMethod(method_index, image_pointer_size_); 2162 if (!method->IsStatic()) { 2163 // Only update static methods. 2164 continue; 2165 } 2166 const void* quick_code = nullptr; 2167 if (has_oat_class) { 2168 OatFile::OatMethod oat_method = oat_class.GetOatMethod(method_index); 2169 quick_code = oat_method.GetQuickCode(); 2170 } 2171 const bool enter_interpreter = NeedsInterpreter(method, quick_code); 2172 if (enter_interpreter) { 2173 // Use interpreter entry point. 2174 // Check whether the method is native, in which case it's generic JNI. 2175 if (quick_code == nullptr && method->IsNative()) { 2176 quick_code = GetQuickGenericJniStub(); 2177 } else { 2178 quick_code = GetQuickToInterpreterBridge(); 2179 } 2180 } 2181 runtime->GetInstrumentation()->UpdateMethodsCode(method, quick_code); 2182 } 2183 // Ignore virtual methods on the iterator. 2184} 2185 2186void ClassLinker::LinkCode(ArtMethod* method, const OatFile::OatClass* oat_class, 2187 uint32_t class_def_method_index) { 2188 Runtime* const runtime = Runtime::Current(); 2189 if (runtime->IsAotCompiler()) { 2190 // The following code only applies to a non-compiler runtime. 2191 return; 2192 } 2193 // Method shouldn't have already been linked. 2194 DCHECK(method->GetEntryPointFromQuickCompiledCode() == nullptr); 2195 if (oat_class != nullptr) { 2196 // Every kind of method should at least get an invoke stub from the oat_method. 2197 // non-abstract methods also get their code pointers. 2198 const OatFile::OatMethod oat_method = oat_class->GetOatMethod(class_def_method_index); 2199 oat_method.LinkMethod(method); 2200 } 2201 2202 // Install entry point from interpreter. 2203 bool enter_interpreter = NeedsInterpreter(method, method->GetEntryPointFromQuickCompiledCode()); 2204 if (enter_interpreter && !method->IsNative()) { 2205 method->SetEntryPointFromInterpreter(artInterpreterToInterpreterBridge); 2206 } else { 2207 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 2208 } 2209 2210 if (method->IsAbstract()) { 2211 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge()); 2212 return; 2213 } 2214 2215 if (method->IsStatic() && !method->IsConstructor()) { 2216 // For static methods excluding the class initializer, install the trampoline. 2217 // It will be replaced by the proper entry point by ClassLinker::FixupStaticTrampolines 2218 // after initializing class (see ClassLinker::InitializeClass method). 2219 method->SetEntryPointFromQuickCompiledCode(GetQuickResolutionStub()); 2220 } else if (enter_interpreter) { 2221 if (!method->IsNative()) { 2222 // Set entry point from compiled code if there's no code or in interpreter only mode. 2223 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge()); 2224 } else { 2225 method->SetEntryPointFromQuickCompiledCode(GetQuickGenericJniStub()); 2226 } 2227 } 2228 2229 if (method->IsNative()) { 2230 // Unregistering restores the dlsym lookup stub. 2231 method->UnregisterNative(); 2232 2233 if (enter_interpreter) { 2234 // We have a native method here without code. Then it should have either the generic JNI 2235 // trampoline as entrypoint (non-static), or the resolution trampoline (static). 2236 // TODO: this doesn't handle all the cases where trampolines may be installed. 2237 const void* entry_point = method->GetEntryPointFromQuickCompiledCode(); 2238 DCHECK(IsQuickGenericJniStub(entry_point) || IsQuickResolutionStub(entry_point)); 2239 } 2240 } 2241} 2242 2243void ClassLinker::SetupClass(const DexFile& dex_file, const DexFile::ClassDef& dex_class_def, 2244 Handle<mirror::Class> klass, mirror::ClassLoader* class_loader) { 2245 CHECK(klass.Get() != nullptr); 2246 CHECK(klass->GetDexCache() != nullptr); 2247 CHECK_EQ(mirror::Class::kStatusNotReady, klass->GetStatus()); 2248 const char* descriptor = dex_file.GetClassDescriptor(dex_class_def); 2249 CHECK(descriptor != nullptr); 2250 2251 klass->SetClass(GetClassRoot(kJavaLangClass)); 2252 uint32_t access_flags = dex_class_def.GetJavaAccessFlags(); 2253 CHECK_EQ(access_flags & ~kAccJavaFlagsMask, 0U); 2254 klass->SetAccessFlags(access_flags); 2255 klass->SetClassLoader(class_loader); 2256 DCHECK_EQ(klass->GetPrimitiveType(), Primitive::kPrimNot); 2257 mirror::Class::SetStatus(klass, mirror::Class::kStatusIdx, nullptr); 2258 2259 klass->SetDexClassDefIndex(dex_file.GetIndexForClassDef(dex_class_def)); 2260 klass->SetDexTypeIndex(dex_class_def.class_idx_); 2261 CHECK(klass->GetDexCacheStrings() != nullptr); 2262} 2263 2264void ClassLinker::LoadClass(Thread* self, const DexFile& dex_file, 2265 const DexFile::ClassDef& dex_class_def, 2266 Handle<mirror::Class> klass) { 2267 const uint8_t* class_data = dex_file.GetClassData(dex_class_def); 2268 if (class_data == nullptr) { 2269 return; // no fields or methods - for example a marker interface 2270 } 2271 bool has_oat_class = false; 2272 if (Runtime::Current()->IsStarted() && !Runtime::Current()->IsAotCompiler()) { 2273 OatFile::OatClass oat_class = FindOatClass(dex_file, klass->GetDexClassDefIndex(), 2274 &has_oat_class); 2275 if (has_oat_class) { 2276 LoadClassMembers(self, dex_file, class_data, klass, &oat_class); 2277 } 2278 } 2279 if (!has_oat_class) { 2280 LoadClassMembers(self, dex_file, class_data, klass, nullptr); 2281 } 2282} 2283 2284ArtField* ClassLinker::AllocArtFieldArray(Thread* self, size_t length) { 2285 auto* const la = Runtime::Current()->GetLinearAlloc(); 2286 auto* ptr = reinterpret_cast<ArtField*>(la->AllocArray<ArtField>(self, length)); 2287 CHECK(ptr!= nullptr); 2288 std::uninitialized_fill_n(ptr, length, ArtField()); 2289 return ptr; 2290} 2291 2292ArtMethod* ClassLinker::AllocArtMethodArray(Thread* self, size_t length) { 2293 const size_t method_size = ArtMethod::ObjectSize(image_pointer_size_); 2294 uintptr_t ptr = reinterpret_cast<uintptr_t>( 2295 Runtime::Current()->GetLinearAlloc()->Alloc(self, method_size * length)); 2296 CHECK_NE(ptr, 0u); 2297 for (size_t i = 0; i < length; ++i) { 2298 new(reinterpret_cast<void*>(ptr + i * method_size)) ArtMethod; 2299 } 2300 return reinterpret_cast<ArtMethod*>(ptr); 2301} 2302 2303void ClassLinker::LoadClassMembers(Thread* self, const DexFile& dex_file, 2304 const uint8_t* class_data, 2305 Handle<mirror::Class> klass, 2306 const OatFile::OatClass* oat_class) { 2307 { 2308 // Note: We cannot have thread suspension until the field and method arrays are setup or else 2309 // Class::VisitFieldRoots may miss some fields or methods. 2310 ScopedAssertNoThreadSuspension nts(self, __FUNCTION__); 2311 // Load static fields. 2312 ClassDataItemIterator it(dex_file, class_data); 2313 const size_t num_sfields = it.NumStaticFields(); 2314 ArtField* sfields = num_sfields != 0 ? AllocArtFieldArray(self, num_sfields) : nullptr; 2315 for (size_t i = 0; it.HasNextStaticField(); i++, it.Next()) { 2316 CHECK_LT(i, num_sfields); 2317 LoadField(it, klass, &sfields[i]); 2318 } 2319 klass->SetSFields(sfields); 2320 klass->SetNumStaticFields(num_sfields); 2321 DCHECK_EQ(klass->NumStaticFields(), num_sfields); 2322 // Load instance fields. 2323 const size_t num_ifields = it.NumInstanceFields(); 2324 ArtField* ifields = num_ifields != 0 ? AllocArtFieldArray(self, num_ifields) : nullptr; 2325 for (size_t i = 0; it.HasNextInstanceField(); i++, it.Next()) { 2326 CHECK_LT(i, num_ifields); 2327 LoadField(it, klass, &ifields[i]); 2328 } 2329 klass->SetIFields(ifields); 2330 klass->SetNumInstanceFields(num_ifields); 2331 DCHECK_EQ(klass->NumInstanceFields(), num_ifields); 2332 // Load methods. 2333 if (it.NumDirectMethods() != 0) { 2334 klass->SetDirectMethodsPtr(AllocArtMethodArray(self, it.NumDirectMethods())); 2335 } 2336 klass->SetNumDirectMethods(it.NumDirectMethods()); 2337 if (it.NumVirtualMethods() != 0) { 2338 klass->SetVirtualMethodsPtr(AllocArtMethodArray(self, it.NumVirtualMethods())); 2339 } 2340 klass->SetNumVirtualMethods(it.NumVirtualMethods()); 2341 size_t class_def_method_index = 0; 2342 uint32_t last_dex_method_index = DexFile::kDexNoIndex; 2343 size_t last_class_def_method_index = 0; 2344 for (size_t i = 0; it.HasNextDirectMethod(); i++, it.Next()) { 2345 ArtMethod* method = klass->GetDirectMethodUnchecked(i, image_pointer_size_); 2346 LoadMethod(self, dex_file, it, klass, method); 2347 LinkCode(method, oat_class, class_def_method_index); 2348 uint32_t it_method_index = it.GetMemberIndex(); 2349 if (last_dex_method_index == it_method_index) { 2350 // duplicate case 2351 method->SetMethodIndex(last_class_def_method_index); 2352 } else { 2353 method->SetMethodIndex(class_def_method_index); 2354 last_dex_method_index = it_method_index; 2355 last_class_def_method_index = class_def_method_index; 2356 } 2357 class_def_method_index++; 2358 } 2359 for (size_t i = 0; it.HasNextVirtualMethod(); i++, it.Next()) { 2360 ArtMethod* method = klass->GetVirtualMethodUnchecked(i, image_pointer_size_); 2361 LoadMethod(self, dex_file, it, klass, method); 2362 DCHECK_EQ(class_def_method_index, it.NumDirectMethods() + i); 2363 LinkCode(method, oat_class, class_def_method_index); 2364 class_def_method_index++; 2365 } 2366 DCHECK(!it.HasNext()); 2367 } 2368 self->AllowThreadSuspension(); 2369} 2370 2371void ClassLinker::LoadField(const ClassDataItemIterator& it, Handle<mirror::Class> klass, 2372 ArtField* dst) { 2373 const uint32_t field_idx = it.GetMemberIndex(); 2374 dst->SetDexFieldIndex(field_idx); 2375 dst->SetDeclaringClass(klass.Get()); 2376 dst->SetAccessFlags(it.GetFieldAccessFlags()); 2377} 2378 2379void ClassLinker::LoadMethod(Thread* self, const DexFile& dex_file, const ClassDataItemIterator& it, 2380 Handle<mirror::Class> klass, ArtMethod* dst) { 2381 uint32_t dex_method_idx = it.GetMemberIndex(); 2382 const DexFile::MethodId& method_id = dex_file.GetMethodId(dex_method_idx); 2383 const char* method_name = dex_file.StringDataByIdx(method_id.name_idx_); 2384 2385 ScopedAssertNoThreadSuspension ants(self, "LoadMethod"); 2386 dst->SetDexMethodIndex(dex_method_idx); 2387 dst->SetDeclaringClass(klass.Get()); 2388 dst->SetCodeItemOffset(it.GetMethodCodeItemOffset()); 2389 2390 dst->SetDexCacheResolvedMethods(klass->GetDexCache()->GetResolvedMethods()); 2391 dst->SetDexCacheResolvedTypes(klass->GetDexCache()->GetResolvedTypes()); 2392 2393 uint32_t access_flags = it.GetMethodAccessFlags(); 2394 2395 if (UNLIKELY(strcmp("finalize", method_name) == 0)) { 2396 // Set finalizable flag on declaring class. 2397 if (strcmp("V", dex_file.GetShorty(method_id.proto_idx_)) == 0) { 2398 // Void return type. 2399 if (klass->GetClassLoader() != nullptr) { // All non-boot finalizer methods are flagged. 2400 klass->SetFinalizable(); 2401 } else { 2402 std::string temp; 2403 const char* klass_descriptor = klass->GetDescriptor(&temp); 2404 // The Enum class declares a "final" finalize() method to prevent subclasses from 2405 // introducing a finalizer. We don't want to set the finalizable flag for Enum or its 2406 // subclasses, so we exclude it here. 2407 // We also want to avoid setting the flag on Object, where we know that finalize() is 2408 // empty. 2409 if (strcmp(klass_descriptor, "Ljava/lang/Object;") != 0 && 2410 strcmp(klass_descriptor, "Ljava/lang/Enum;") != 0) { 2411 klass->SetFinalizable(); 2412 } 2413 } 2414 } 2415 } else if (method_name[0] == '<') { 2416 // Fix broken access flags for initializers. Bug 11157540. 2417 bool is_init = (strcmp("<init>", method_name) == 0); 2418 bool is_clinit = !is_init && (strcmp("<clinit>", method_name) == 0); 2419 if (UNLIKELY(!is_init && !is_clinit)) { 2420 LOG(WARNING) << "Unexpected '<' at start of method name " << method_name; 2421 } else { 2422 if (UNLIKELY((access_flags & kAccConstructor) == 0)) { 2423 LOG(WARNING) << method_name << " didn't have expected constructor access flag in class " 2424 << PrettyDescriptor(klass.Get()) << " in dex file " << dex_file.GetLocation(); 2425 access_flags |= kAccConstructor; 2426 } 2427 } 2428 } 2429 dst->SetAccessFlags(access_flags); 2430} 2431 2432void ClassLinker::AppendToBootClassPath(Thread* self, const DexFile& dex_file) { 2433 StackHandleScope<1> hs(self); 2434 Handle<mirror::DexCache> dex_cache(hs.NewHandle(AllocDexCache(self, dex_file))); 2435 CHECK(dex_cache.Get() != nullptr) << "Failed to allocate dex cache for " 2436 << dex_file.GetLocation(); 2437 AppendToBootClassPath(dex_file, dex_cache); 2438} 2439 2440void ClassLinker::AppendToBootClassPath(const DexFile& dex_file, 2441 Handle<mirror::DexCache> dex_cache) { 2442 CHECK(dex_cache.Get() != nullptr) << dex_file.GetLocation(); 2443 boot_class_path_.push_back(&dex_file); 2444 RegisterDexFile(dex_file, dex_cache); 2445} 2446 2447bool ClassLinker::IsDexFileRegisteredLocked(const DexFile& dex_file) { 2448 dex_lock_.AssertSharedHeld(Thread::Current()); 2449 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2450 mirror::DexCache* dex_cache = GetDexCache(i); 2451 if (dex_cache->GetDexFile() == &dex_file) { 2452 return true; 2453 } 2454 } 2455 return false; 2456} 2457 2458bool ClassLinker::IsDexFileRegistered(const DexFile& dex_file) { 2459 ReaderMutexLock mu(Thread::Current(), dex_lock_); 2460 return IsDexFileRegisteredLocked(dex_file); 2461} 2462 2463void ClassLinker::RegisterDexFileLocked(const DexFile& dex_file, 2464 Handle<mirror::DexCache> dex_cache) { 2465 dex_lock_.AssertExclusiveHeld(Thread::Current()); 2466 CHECK(dex_cache.Get() != nullptr) << dex_file.GetLocation(); 2467 CHECK(dex_cache->GetLocation()->Equals(dex_file.GetLocation())) 2468 << dex_cache->GetLocation()->ToModifiedUtf8() << " " << dex_file.GetLocation(); 2469 dex_caches_.push_back(GcRoot<mirror::DexCache>(dex_cache.Get())); 2470 dex_cache->SetDexFile(&dex_file); 2471 if (log_new_dex_caches_roots_) { 2472 // TODO: This is not safe if we can remove dex caches. 2473 new_dex_cache_roots_.push_back(dex_caches_.size() - 1); 2474 } 2475} 2476 2477void ClassLinker::RegisterDexFile(const DexFile& dex_file) { 2478 Thread* self = Thread::Current(); 2479 { 2480 ReaderMutexLock mu(self, dex_lock_); 2481 if (IsDexFileRegisteredLocked(dex_file)) { 2482 return; 2483 } 2484 } 2485 // Don't alloc while holding the lock, since allocation may need to 2486 // suspend all threads and another thread may need the dex_lock_ to 2487 // get to a suspend point. 2488 StackHandleScope<1> hs(self); 2489 Handle<mirror::DexCache> dex_cache(hs.NewHandle(AllocDexCache(self, dex_file))); 2490 CHECK(dex_cache.Get() != nullptr) << "Failed to allocate dex cache for " 2491 << dex_file.GetLocation(); 2492 { 2493 WriterMutexLock mu(self, dex_lock_); 2494 if (IsDexFileRegisteredLocked(dex_file)) { 2495 return; 2496 } 2497 RegisterDexFileLocked(dex_file, dex_cache); 2498 } 2499} 2500 2501void ClassLinker::RegisterDexFile(const DexFile& dex_file, 2502 Handle<mirror::DexCache> dex_cache) { 2503 WriterMutexLock mu(Thread::Current(), dex_lock_); 2504 RegisterDexFileLocked(dex_file, dex_cache); 2505} 2506 2507mirror::DexCache* ClassLinker::FindDexCache(const DexFile& dex_file) { 2508 ReaderMutexLock mu(Thread::Current(), dex_lock_); 2509 // Search assuming unique-ness of dex file. 2510 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2511 mirror::DexCache* dex_cache = GetDexCache(i); 2512 if (dex_cache->GetDexFile() == &dex_file) { 2513 return dex_cache; 2514 } 2515 } 2516 // Search matching by location name. 2517 std::string location(dex_file.GetLocation()); 2518 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2519 mirror::DexCache* dex_cache = GetDexCache(i); 2520 if (dex_cache->GetDexFile()->GetLocation() == location) { 2521 return dex_cache; 2522 } 2523 } 2524 // Failure, dump diagnostic and abort. 2525 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2526 mirror::DexCache* dex_cache = GetDexCache(i); 2527 LOG(ERROR) << "Registered dex file " << i << " = " << dex_cache->GetDexFile()->GetLocation(); 2528 } 2529 LOG(FATAL) << "Failed to find DexCache for DexFile " << location; 2530 UNREACHABLE(); 2531} 2532 2533void ClassLinker::FixupDexCaches(ArtMethod* resolution_method) { 2534 ReaderMutexLock mu(Thread::Current(), dex_lock_); 2535 for (auto& dex_cache : dex_caches_) { 2536 dex_cache.Read()->Fixup(resolution_method, image_pointer_size_); 2537 } 2538} 2539 2540mirror::Class* ClassLinker::CreatePrimitiveClass(Thread* self, Primitive::Type type) { 2541 mirror::Class* klass = AllocClass(self, mirror::Class::PrimitiveClassSize(image_pointer_size_)); 2542 if (UNLIKELY(klass == nullptr)) { 2543 self->AssertPendingOOMException(); 2544 return nullptr; 2545 } 2546 return InitializePrimitiveClass(klass, type); 2547} 2548 2549mirror::Class* ClassLinker::InitializePrimitiveClass(mirror::Class* primitive_class, 2550 Primitive::Type type) { 2551 CHECK(primitive_class != nullptr); 2552 // Must hold lock on object when initializing. 2553 Thread* self = Thread::Current(); 2554 StackHandleScope<1> hs(self); 2555 Handle<mirror::Class> h_class(hs.NewHandle(primitive_class)); 2556 ObjectLock<mirror::Class> lock(self, h_class); 2557 h_class->SetAccessFlags(kAccPublic | kAccFinal | kAccAbstract); 2558 h_class->SetPrimitiveType(type); 2559 mirror::Class::SetStatus(h_class, mirror::Class::kStatusInitialized, self); 2560 const char* descriptor = Primitive::Descriptor(type); 2561 mirror::Class* existing = InsertClass(descriptor, h_class.Get(), 2562 ComputeModifiedUtf8Hash(descriptor)); 2563 CHECK(existing == nullptr) << "InitPrimitiveClass(" << type << ") failed"; 2564 return h_class.Get(); 2565} 2566 2567// Create an array class (i.e. the class object for the array, not the 2568// array itself). "descriptor" looks like "[C" or "[[[[B" or 2569// "[Ljava/lang/String;". 2570// 2571// If "descriptor" refers to an array of primitives, look up the 2572// primitive type's internally-generated class object. 2573// 2574// "class_loader" is the class loader of the class that's referring to 2575// us. It's used to ensure that we're looking for the element type in 2576// the right context. It does NOT become the class loader for the 2577// array class; that always comes from the base element class. 2578// 2579// Returns null with an exception raised on failure. 2580mirror::Class* ClassLinker::CreateArrayClass(Thread* self, const char* descriptor, size_t hash, 2581 Handle<mirror::ClassLoader> class_loader) { 2582 // Identify the underlying component type 2583 CHECK_EQ('[', descriptor[0]); 2584 StackHandleScope<2> hs(self); 2585 MutableHandle<mirror::Class> component_type(hs.NewHandle(FindClass(self, descriptor + 1, 2586 class_loader))); 2587 if (component_type.Get() == nullptr) { 2588 DCHECK(self->IsExceptionPending()); 2589 // We need to accept erroneous classes as component types. 2590 const size_t component_hash = ComputeModifiedUtf8Hash(descriptor + 1); 2591 component_type.Assign(LookupClass(self, descriptor + 1, component_hash, class_loader.Get())); 2592 if (component_type.Get() == nullptr) { 2593 DCHECK(self->IsExceptionPending()); 2594 return nullptr; 2595 } else { 2596 self->ClearException(); 2597 } 2598 } 2599 if (UNLIKELY(component_type->IsPrimitiveVoid())) { 2600 ThrowNoClassDefFoundError("Attempt to create array of void primitive type"); 2601 return nullptr; 2602 } 2603 // See if the component type is already loaded. Array classes are 2604 // always associated with the class loader of their underlying 2605 // element type -- an array of Strings goes with the loader for 2606 // java/lang/String -- so we need to look for it there. (The 2607 // caller should have checked for the existence of the class 2608 // before calling here, but they did so with *their* class loader, 2609 // not the component type's loader.) 2610 // 2611 // If we find it, the caller adds "loader" to the class' initiating 2612 // loader list, which should prevent us from going through this again. 2613 // 2614 // This call is unnecessary if "loader" and "component_type->GetClassLoader()" 2615 // are the same, because our caller (FindClass) just did the 2616 // lookup. (Even if we get this wrong we still have correct behavior, 2617 // because we effectively do this lookup again when we add the new 2618 // class to the hash table --- necessary because of possible races with 2619 // other threads.) 2620 if (class_loader.Get() != component_type->GetClassLoader()) { 2621 mirror::Class* new_class = LookupClass(self, descriptor, hash, component_type->GetClassLoader()); 2622 if (new_class != nullptr) { 2623 return new_class; 2624 } 2625 } 2626 2627 // Fill out the fields in the Class. 2628 // 2629 // It is possible to execute some methods against arrays, because 2630 // all arrays are subclasses of java_lang_Object_, so we need to set 2631 // up a vtable. We can just point at the one in java_lang_Object_. 2632 // 2633 // Array classes are simple enough that we don't need to do a full 2634 // link step. 2635 auto new_class = hs.NewHandle<mirror::Class>(nullptr); 2636 if (UNLIKELY(!init_done_)) { 2637 // Classes that were hand created, ie not by FindSystemClass 2638 if (strcmp(descriptor, "[Ljava/lang/Class;") == 0) { 2639 new_class.Assign(GetClassRoot(kClassArrayClass)); 2640 } else if (strcmp(descriptor, "[Ljava/lang/Object;") == 0) { 2641 new_class.Assign(GetClassRoot(kObjectArrayClass)); 2642 } else if (strcmp(descriptor, GetClassRootDescriptor(kJavaLangStringArrayClass)) == 0) { 2643 new_class.Assign(GetClassRoot(kJavaLangStringArrayClass)); 2644 } else if (strcmp(descriptor, "[C") == 0) { 2645 new_class.Assign(GetClassRoot(kCharArrayClass)); 2646 } else if (strcmp(descriptor, "[I") == 0) { 2647 new_class.Assign(GetClassRoot(kIntArrayClass)); 2648 } else if (strcmp(descriptor, "[J") == 0) { 2649 new_class.Assign(GetClassRoot(kLongArrayClass)); 2650 } 2651 } 2652 if (new_class.Get() == nullptr) { 2653 new_class.Assign(AllocClass(self, mirror::Array::ClassSize(image_pointer_size_))); 2654 if (new_class.Get() == nullptr) { 2655 self->AssertPendingOOMException(); 2656 return nullptr; 2657 } 2658 new_class->SetComponentType(component_type.Get()); 2659 } 2660 ObjectLock<mirror::Class> lock(self, new_class); // Must hold lock on object when initializing. 2661 DCHECK(new_class->GetComponentType() != nullptr); 2662 mirror::Class* java_lang_Object = GetClassRoot(kJavaLangObject); 2663 new_class->SetSuperClass(java_lang_Object); 2664 new_class->SetVTable(java_lang_Object->GetVTable()); 2665 new_class->SetPrimitiveType(Primitive::kPrimNot); 2666 new_class->SetClassLoader(component_type->GetClassLoader()); 2667 mirror::Class::SetStatus(new_class, mirror::Class::kStatusLoaded, self); 2668 { 2669 ArtMethod* imt[mirror::Class::kImtSize]; 2670 std::fill_n(imt, arraysize(imt), Runtime::Current()->GetImtUnimplementedMethod()); 2671 new_class->PopulateEmbeddedImtAndVTable(imt, image_pointer_size_); 2672 } 2673 mirror::Class::SetStatus(new_class, mirror::Class::kStatusInitialized, self); 2674 // don't need to set new_class->SetObjectSize(..) 2675 // because Object::SizeOf delegates to Array::SizeOf 2676 2677 2678 // All arrays have java/lang/Cloneable and java/io/Serializable as 2679 // interfaces. We need to set that up here, so that stuff like 2680 // "instanceof" works right. 2681 // 2682 // Note: The GC could run during the call to FindSystemClass, 2683 // so we need to make sure the class object is GC-valid while we're in 2684 // there. Do this by clearing the interface list so the GC will just 2685 // think that the entries are null. 2686 2687 2688 // Use the single, global copies of "interfaces" and "iftable" 2689 // (remember not to free them for arrays). 2690 { 2691 mirror::IfTable* array_iftable = array_iftable_.Read(); 2692 CHECK(array_iftable != nullptr); 2693 new_class->SetIfTable(array_iftable); 2694 } 2695 2696 // Inherit access flags from the component type. 2697 int access_flags = new_class->GetComponentType()->GetAccessFlags(); 2698 // Lose any implementation detail flags; in particular, arrays aren't finalizable. 2699 access_flags &= kAccJavaFlagsMask; 2700 // Arrays can't be used as a superclass or interface, so we want to add "abstract final" 2701 // and remove "interface". 2702 access_flags |= kAccAbstract | kAccFinal; 2703 access_flags &= ~kAccInterface; 2704 2705 new_class->SetAccessFlags(access_flags); 2706 2707 mirror::Class* existing = InsertClass(descriptor, new_class.Get(), hash); 2708 if (existing == nullptr) { 2709 return new_class.Get(); 2710 } 2711 // Another thread must have loaded the class after we 2712 // started but before we finished. Abandon what we've 2713 // done. 2714 // 2715 // (Yes, this happens.) 2716 2717 return existing; 2718} 2719 2720mirror::Class* ClassLinker::FindPrimitiveClass(char type) { 2721 switch (type) { 2722 case 'B': 2723 return GetClassRoot(kPrimitiveByte); 2724 case 'C': 2725 return GetClassRoot(kPrimitiveChar); 2726 case 'D': 2727 return GetClassRoot(kPrimitiveDouble); 2728 case 'F': 2729 return GetClassRoot(kPrimitiveFloat); 2730 case 'I': 2731 return GetClassRoot(kPrimitiveInt); 2732 case 'J': 2733 return GetClassRoot(kPrimitiveLong); 2734 case 'S': 2735 return GetClassRoot(kPrimitiveShort); 2736 case 'Z': 2737 return GetClassRoot(kPrimitiveBoolean); 2738 case 'V': 2739 return GetClassRoot(kPrimitiveVoid); 2740 default: 2741 break; 2742 } 2743 std::string printable_type(PrintableChar(type)); 2744 ThrowNoClassDefFoundError("Not a primitive type: %s", printable_type.c_str()); 2745 return nullptr; 2746} 2747 2748mirror::Class* ClassLinker::InsertClass(const char* descriptor, mirror::Class* klass, 2749 size_t hash) { 2750 if (VLOG_IS_ON(class_linker)) { 2751 mirror::DexCache* dex_cache = klass->GetDexCache(); 2752 std::string source; 2753 if (dex_cache != nullptr) { 2754 source += " from "; 2755 source += dex_cache->GetLocation()->ToModifiedUtf8(); 2756 } 2757 LOG(INFO) << "Loaded class " << descriptor << source; 2758 } 2759 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2760 mirror::Class* existing = LookupClassFromTableLocked(descriptor, klass->GetClassLoader(), hash); 2761 if (existing != nullptr) { 2762 return existing; 2763 } 2764 if (kIsDebugBuild && !klass->IsTemp() && klass->GetClassLoader() == nullptr && 2765 dex_cache_image_class_lookup_required_) { 2766 // Check a class loaded with the system class loader matches one in the image if the class 2767 // is in the image. 2768 existing = LookupClassFromImage(descriptor); 2769 if (existing != nullptr) { 2770 CHECK_EQ(klass, existing); 2771 } 2772 } 2773 VerifyObject(klass); 2774 class_table_.InsertWithHash(GcRoot<mirror::Class>(klass), hash); 2775 if (log_new_class_table_roots_) { 2776 new_class_roots_.push_back(GcRoot<mirror::Class>(klass)); 2777 } 2778 return nullptr; 2779} 2780 2781void ClassLinker::UpdateClassVirtualMethods(mirror::Class* klass, ArtMethod* new_methods, 2782 size_t new_num_methods) { 2783 // classlinker_classes_lock_ is used to guard against races between root marking and changing the 2784 // direct and virtual method pointers. 2785 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2786 klass->SetNumVirtualMethods(new_num_methods); 2787 klass->SetVirtualMethodsPtr(new_methods); 2788 if (log_new_class_table_roots_) { 2789 new_class_roots_.push_back(GcRoot<mirror::Class>(klass)); 2790 } 2791} 2792 2793mirror::Class* ClassLinker::UpdateClass(const char* descriptor, mirror::Class* klass, 2794 size_t hash) { 2795 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2796 auto existing_it = class_table_.FindWithHash(std::make_pair(descriptor, klass->GetClassLoader()), 2797 hash); 2798 CHECK(existing_it != class_table_.end()); 2799 mirror::Class* existing = existing_it->Read(); 2800 CHECK_NE(existing, klass) << descriptor; 2801 CHECK(!existing->IsResolved()) << descriptor; 2802 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusResolving) << descriptor; 2803 2804 CHECK(!klass->IsTemp()) << descriptor; 2805 if (kIsDebugBuild && klass->GetClassLoader() == nullptr && 2806 dex_cache_image_class_lookup_required_) { 2807 // Check a class loaded with the system class loader matches one in the image if the class 2808 // is in the image. 2809 existing = LookupClassFromImage(descriptor); 2810 if (existing != nullptr) { 2811 CHECK_EQ(klass, existing) << descriptor; 2812 } 2813 } 2814 VerifyObject(klass); 2815 2816 // Update the element in the hash set. 2817 *existing_it = GcRoot<mirror::Class>(klass); 2818 if (log_new_class_table_roots_) { 2819 new_class_roots_.push_back(GcRoot<mirror::Class>(klass)); 2820 } 2821 2822 return existing; 2823} 2824 2825bool ClassLinker::RemoveClass(const char* descriptor, mirror::ClassLoader* class_loader) { 2826 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2827 auto pair = std::make_pair(descriptor, class_loader); 2828 auto it = class_table_.Find(pair); 2829 if (it != class_table_.end()) { 2830 class_table_.Erase(it); 2831 return true; 2832 } 2833 it = pre_zygote_class_table_.Find(pair); 2834 if (it != pre_zygote_class_table_.end()) { 2835 pre_zygote_class_table_.Erase(it); 2836 return true; 2837 } 2838 return false; 2839} 2840 2841mirror::Class* ClassLinker::LookupClass(Thread* self, const char* descriptor, size_t hash, 2842 mirror::ClassLoader* class_loader) { 2843 { 2844 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 2845 mirror::Class* result = LookupClassFromTableLocked(descriptor, class_loader, hash); 2846 if (result != nullptr) { 2847 return result; 2848 } 2849 } 2850 if (class_loader != nullptr || !dex_cache_image_class_lookup_required_) { 2851 return nullptr; 2852 } else { 2853 // Lookup failed but need to search dex_caches_. 2854 mirror::Class* result = LookupClassFromImage(descriptor); 2855 if (result != nullptr) { 2856 InsertClass(descriptor, result, hash); 2857 } else { 2858 // Searching the image dex files/caches failed, we don't want to get into this situation 2859 // often as map searches are faster, so after kMaxFailedDexCacheLookups move all image 2860 // classes into the class table. 2861 constexpr uint32_t kMaxFailedDexCacheLookups = 1000; 2862 if (++failed_dex_cache_class_lookups_ > kMaxFailedDexCacheLookups) { 2863 MoveImageClassesToClassTable(); 2864 } 2865 } 2866 return result; 2867 } 2868} 2869 2870mirror::Class* ClassLinker::LookupClassFromTableLocked(const char* descriptor, 2871 mirror::ClassLoader* class_loader, 2872 size_t hash) { 2873 auto descriptor_pair = std::make_pair(descriptor, class_loader); 2874 auto it = pre_zygote_class_table_.FindWithHash(descriptor_pair, hash); 2875 if (it == pre_zygote_class_table_.end()) { 2876 it = class_table_.FindWithHash(descriptor_pair, hash); 2877 if (it == class_table_.end()) { 2878 return nullptr; 2879 } 2880 } 2881 return it->Read(); 2882} 2883 2884static mirror::ObjectArray<mirror::DexCache>* GetImageDexCaches() 2885 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 2886 gc::space::ImageSpace* image = Runtime::Current()->GetHeap()->GetImageSpace(); 2887 CHECK(image != nullptr); 2888 mirror::Object* root = image->GetImageHeader().GetImageRoot(ImageHeader::kDexCaches); 2889 return root->AsObjectArray<mirror::DexCache>(); 2890} 2891 2892void ClassLinker::MoveImageClassesToClassTable() { 2893 Thread* self = Thread::Current(); 2894 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_); 2895 if (!dex_cache_image_class_lookup_required_) { 2896 return; // All dex cache classes are already in the class table. 2897 } 2898 ScopedAssertNoThreadSuspension ants(self, "Moving image classes to class table"); 2899 mirror::ObjectArray<mirror::DexCache>* dex_caches = GetImageDexCaches(); 2900 std::string temp; 2901 for (int32_t i = 0; i < dex_caches->GetLength(); i++) { 2902 mirror::DexCache* dex_cache = dex_caches->Get(i); 2903 mirror::ObjectArray<mirror::Class>* types = dex_cache->GetResolvedTypes(); 2904 for (int32_t j = 0; j < types->GetLength(); j++) { 2905 mirror::Class* klass = types->Get(j); 2906 if (klass != nullptr) { 2907 DCHECK(klass->GetClassLoader() == nullptr); 2908 const char* descriptor = klass->GetDescriptor(&temp); 2909 size_t hash = ComputeModifiedUtf8Hash(descriptor); 2910 mirror::Class* existing = LookupClassFromTableLocked(descriptor, nullptr, hash); 2911 if (existing != nullptr) { 2912 CHECK_EQ(existing, klass) << PrettyClassAndClassLoader(existing) << " != " 2913 << PrettyClassAndClassLoader(klass); 2914 } else { 2915 class_table_.Insert(GcRoot<mirror::Class>(klass)); 2916 if (log_new_class_table_roots_) { 2917 new_class_roots_.push_back(GcRoot<mirror::Class>(klass)); 2918 } 2919 } 2920 } 2921 } 2922 } 2923 dex_cache_image_class_lookup_required_ = false; 2924} 2925 2926void ClassLinker::MoveClassTableToPreZygote() { 2927 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2928 DCHECK(pre_zygote_class_table_.Empty()); 2929 pre_zygote_class_table_ = std::move(class_table_); 2930 class_table_.Clear(); 2931} 2932 2933mirror::Class* ClassLinker::LookupClassFromImage(const char* descriptor) { 2934 ScopedAssertNoThreadSuspension ants(Thread::Current(), "Image class lookup"); 2935 mirror::ObjectArray<mirror::DexCache>* dex_caches = GetImageDexCaches(); 2936 for (int32_t i = 0; i < dex_caches->GetLength(); ++i) { 2937 mirror::DexCache* dex_cache = dex_caches->Get(i); 2938 const DexFile* dex_file = dex_cache->GetDexFile(); 2939 // Try binary searching the string/type index. 2940 const DexFile::StringId* string_id = dex_file->FindStringId(descriptor); 2941 if (string_id != nullptr) { 2942 const DexFile::TypeId* type_id = 2943 dex_file->FindTypeId(dex_file->GetIndexForStringId(*string_id)); 2944 if (type_id != nullptr) { 2945 uint16_t type_idx = dex_file->GetIndexForTypeId(*type_id); 2946 mirror::Class* klass = dex_cache->GetResolvedType(type_idx); 2947 if (klass != nullptr) { 2948 return klass; 2949 } 2950 } 2951 } 2952 } 2953 return nullptr; 2954} 2955 2956void ClassLinker::LookupClasses(const char* descriptor, std::vector<mirror::Class*>& result) { 2957 result.clear(); 2958 if (dex_cache_image_class_lookup_required_) { 2959 MoveImageClassesToClassTable(); 2960 } 2961 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2962 while (true) { 2963 auto it = class_table_.Find(descriptor); 2964 if (it == class_table_.end()) { 2965 break; 2966 } 2967 result.push_back(it->Read()); 2968 class_table_.Erase(it); 2969 } 2970 for (mirror::Class* k : result) { 2971 class_table_.Insert(GcRoot<mirror::Class>(k)); 2972 } 2973 size_t pre_zygote_start = result.size(); 2974 // Now handle the pre zygote table. 2975 // Note: This dirties the pre-zygote table but shouldn't be an issue since LookupClasses is only 2976 // called from the debugger. 2977 while (true) { 2978 auto it = pre_zygote_class_table_.Find(descriptor); 2979 if (it == pre_zygote_class_table_.end()) { 2980 break; 2981 } 2982 result.push_back(it->Read()); 2983 pre_zygote_class_table_.Erase(it); 2984 } 2985 for (size_t i = pre_zygote_start; i < result.size(); ++i) { 2986 pre_zygote_class_table_.Insert(GcRoot<mirror::Class>(result[i])); 2987 } 2988} 2989 2990void ClassLinker::VerifyClass(Thread* self, Handle<mirror::Class> klass) { 2991 // TODO: assert that the monitor on the Class is held 2992 ObjectLock<mirror::Class> lock(self, klass); 2993 2994 // Don't attempt to re-verify if already sufficiently verified. 2995 if (klass->IsVerified()) { 2996 EnsurePreverifiedMethods(klass); 2997 return; 2998 } 2999 if (klass->IsCompileTimeVerified() && Runtime::Current()->IsAotCompiler()) { 3000 return; 3001 } 3002 3003 // The class might already be erroneous, for example at compile time if we attempted to verify 3004 // this class as a parent to another. 3005 if (klass->IsErroneous()) { 3006 ThrowEarlierClassFailure(klass.Get()); 3007 return; 3008 } 3009 3010 if (klass->GetStatus() == mirror::Class::kStatusResolved) { 3011 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerifying, self); 3012 } else { 3013 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime) 3014 << PrettyClass(klass.Get()); 3015 CHECK(!Runtime::Current()->IsAotCompiler()); 3016 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerifyingAtRuntime, self); 3017 } 3018 3019 // Skip verification if disabled. 3020 if (!Runtime::Current()->IsVerificationEnabled()) { 3021 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self); 3022 EnsurePreverifiedMethods(klass); 3023 return; 3024 } 3025 3026 // Verify super class. 3027 StackHandleScope<2> hs(self); 3028 Handle<mirror::Class> super(hs.NewHandle(klass->GetSuperClass())); 3029 if (super.Get() != nullptr) { 3030 // Acquire lock to prevent races on verifying the super class. 3031 ObjectLock<mirror::Class> super_lock(self, super); 3032 3033 if (!super->IsVerified() && !super->IsErroneous()) { 3034 VerifyClass(self, super); 3035 } 3036 if (!super->IsCompileTimeVerified()) { 3037 std::string error_msg( 3038 StringPrintf("Rejecting class %s that attempts to sub-class erroneous class %s", 3039 PrettyDescriptor(klass.Get()).c_str(), 3040 PrettyDescriptor(super.Get()).c_str())); 3041 LOG(WARNING) << error_msg << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8(); 3042 Handle<mirror::Throwable> cause(hs.NewHandle(self->GetException())); 3043 if (cause.Get() != nullptr) { 3044 self->ClearException(); 3045 } 3046 ThrowVerifyError(klass.Get(), "%s", error_msg.c_str()); 3047 if (cause.Get() != nullptr) { 3048 self->GetException()->SetCause(cause.Get()); 3049 } 3050 ClassReference ref(klass->GetDexCache()->GetDexFile(), klass->GetDexClassDefIndex()); 3051 if (Runtime::Current()->IsAotCompiler()) { 3052 Runtime::Current()->GetCompilerCallbacks()->ClassRejected(ref); 3053 } 3054 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3055 return; 3056 } 3057 } 3058 3059 // Try to use verification information from the oat file, otherwise do runtime verification. 3060 const DexFile& dex_file = *klass->GetDexCache()->GetDexFile(); 3061 mirror::Class::Status oat_file_class_status(mirror::Class::kStatusNotReady); 3062 bool preverified = VerifyClassUsingOatFile(dex_file, klass.Get(), oat_file_class_status); 3063 if (oat_file_class_status == mirror::Class::kStatusError) { 3064 VLOG(class_linker) << "Skipping runtime verification of erroneous class " 3065 << PrettyDescriptor(klass.Get()) << " in " 3066 << klass->GetDexCache()->GetLocation()->ToModifiedUtf8(); 3067 ThrowVerifyError(klass.Get(), "Rejecting class %s because it failed compile-time verification", 3068 PrettyDescriptor(klass.Get()).c_str()); 3069 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3070 return; 3071 } 3072 verifier::MethodVerifier::FailureKind verifier_failure = verifier::MethodVerifier::kNoFailure; 3073 std::string error_msg; 3074 if (!preverified) { 3075 verifier_failure = verifier::MethodVerifier::VerifyClass(self, klass.Get(), 3076 Runtime::Current()->IsAotCompiler(), 3077 &error_msg); 3078 } 3079 if (preverified || verifier_failure != verifier::MethodVerifier::kHardFailure) { 3080 if (!preverified && verifier_failure != verifier::MethodVerifier::kNoFailure) { 3081 VLOG(class_linker) << "Soft verification failure in class " << PrettyDescriptor(klass.Get()) 3082 << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8() 3083 << " because: " << error_msg; 3084 } 3085 self->AssertNoPendingException(); 3086 // Make sure all classes referenced by catch blocks are resolved. 3087 ResolveClassExceptionHandlerTypes(dex_file, klass); 3088 if (verifier_failure == verifier::MethodVerifier::kNoFailure) { 3089 // Even though there were no verifier failures we need to respect whether the super-class 3090 // was verified or requiring runtime reverification. 3091 if (super.Get() == nullptr || super->IsVerified()) { 3092 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self); 3093 } else { 3094 CHECK_EQ(super->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime); 3095 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetryVerificationAtRuntime, self); 3096 // Pretend a soft failure occured so that we don't consider the class verified below. 3097 verifier_failure = verifier::MethodVerifier::kSoftFailure; 3098 } 3099 } else { 3100 CHECK_EQ(verifier_failure, verifier::MethodVerifier::kSoftFailure); 3101 // Soft failures at compile time should be retried at runtime. Soft 3102 // failures at runtime will be handled by slow paths in the generated 3103 // code. Set status accordingly. 3104 if (Runtime::Current()->IsAotCompiler()) { 3105 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetryVerificationAtRuntime, self); 3106 } else { 3107 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self); 3108 // As this is a fake verified status, make sure the methods are _not_ marked preverified 3109 // later. 3110 klass->SetPreverified(); 3111 } 3112 } 3113 } else { 3114 LOG(WARNING) << "Verification failed on class " << PrettyDescriptor(klass.Get()) 3115 << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8() 3116 << " because: " << error_msg; 3117 self->AssertNoPendingException(); 3118 ThrowVerifyError(klass.Get(), "%s", error_msg.c_str()); 3119 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3120 } 3121 if (preverified || verifier_failure == verifier::MethodVerifier::kNoFailure) { 3122 // Class is verified so we don't need to do any access check on its methods. 3123 // Let the interpreter know it by setting the kAccPreverified flag onto each 3124 // method. 3125 // Note: we're going here during compilation and at runtime. When we set the 3126 // kAccPreverified flag when compiling image classes, the flag is recorded 3127 // in the image and is set when loading the image. 3128 EnsurePreverifiedMethods(klass); 3129 } 3130} 3131 3132void ClassLinker::EnsurePreverifiedMethods(Handle<mirror::Class> klass) { 3133 if (!klass->IsPreverified()) { 3134 klass->SetPreverifiedFlagOnAllMethods(image_pointer_size_); 3135 klass->SetPreverified(); 3136 } 3137} 3138 3139bool ClassLinker::VerifyClassUsingOatFile(const DexFile& dex_file, mirror::Class* klass, 3140 mirror::Class::Status& oat_file_class_status) { 3141 // If we're compiling, we can only verify the class using the oat file if 3142 // we are not compiling the image or if the class we're verifying is not part of 3143 // the app. In other words, we will only check for preverification of bootclasspath 3144 // classes. 3145 if (Runtime::Current()->IsAotCompiler()) { 3146 // Are we compiling the bootclasspath? 3147 if (Runtime::Current()->GetCompilerCallbacks()->IsBootImage()) { 3148 return false; 3149 } 3150 // We are compiling an app (not the image). 3151 3152 // Is this an app class? (I.e. not a bootclasspath class) 3153 if (klass->GetClassLoader() != nullptr) { 3154 return false; 3155 } 3156 } 3157 3158 const OatFile::OatDexFile* oat_dex_file = dex_file.GetOatDexFile(); 3159 // In case we run without an image there won't be a backing oat file. 3160 if (oat_dex_file == nullptr) { 3161 return false; 3162 } 3163 3164 // We may be running with a preopted oat file but without image. In this case, 3165 // we don't skip verification of preverified classes to ensure we initialize 3166 // dex caches with all types resolved during verification. 3167 // We need to trust image classes, as these might be coming out of a pre-opted, quickened boot 3168 // image (that we just failed loading), and the verifier can't be run on quickened opcodes when 3169 // the runtime isn't started. On the other hand, app classes can be re-verified even if they are 3170 // already pre-opted, as then the runtime is started. 3171 if (!Runtime::Current()->IsAotCompiler() && 3172 !Runtime::Current()->GetHeap()->HasImageSpace() && 3173 klass->GetClassLoader() != nullptr) { 3174 return false; 3175 } 3176 3177 uint16_t class_def_index = klass->GetDexClassDefIndex(); 3178 oat_file_class_status = oat_dex_file->GetOatClass(class_def_index).GetStatus(); 3179 if (oat_file_class_status == mirror::Class::kStatusVerified || 3180 oat_file_class_status == mirror::Class::kStatusInitialized) { 3181 return true; 3182 } 3183 if (oat_file_class_status == mirror::Class::kStatusRetryVerificationAtRuntime) { 3184 // Compile time verification failed with a soft error. Compile time verification can fail 3185 // because we have incomplete type information. Consider the following: 3186 // class ... { 3187 // Foo x; 3188 // .... () { 3189 // if (...) { 3190 // v1 gets assigned a type of resolved class Foo 3191 // } else { 3192 // v1 gets assigned a type of unresolved class Bar 3193 // } 3194 // iput x = v1 3195 // } } 3196 // when we merge v1 following the if-the-else it results in Conflict 3197 // (see verifier::RegType::Merge) as we can't know the type of Bar and we could possibly be 3198 // allowing an unsafe assignment to the field x in the iput (javac may have compiled this as 3199 // it knew Bar was a sub-class of Foo, but for us this may have been moved into a separate apk 3200 // at compile time). 3201 return false; 3202 } 3203 if (oat_file_class_status == mirror::Class::kStatusError) { 3204 // Compile time verification failed with a hard error. This is caused by invalid instructions 3205 // in the class. These errors are unrecoverable. 3206 return false; 3207 } 3208 if (oat_file_class_status == mirror::Class::kStatusNotReady) { 3209 // Status is uninitialized if we couldn't determine the status at compile time, for example, 3210 // not loading the class. 3211 // TODO: when the verifier doesn't rely on Class-es failing to resolve/load the type hierarchy 3212 // isn't a problem and this case shouldn't occur 3213 return false; 3214 } 3215 std::string temp; 3216 LOG(FATAL) << "Unexpected class status: " << oat_file_class_status 3217 << " " << dex_file.GetLocation() << " " << PrettyClass(klass) << " " 3218 << klass->GetDescriptor(&temp); 3219 UNREACHABLE(); 3220} 3221 3222void ClassLinker::ResolveClassExceptionHandlerTypes(const DexFile& dex_file, 3223 Handle<mirror::Class> klass) { 3224 for (size_t i = 0; i < klass->NumDirectMethods(); i++) { 3225 ResolveMethodExceptionHandlerTypes(dex_file, klass->GetDirectMethod(i, image_pointer_size_)); 3226 } 3227 for (size_t i = 0; i < klass->NumVirtualMethods(); i++) { 3228 ResolveMethodExceptionHandlerTypes(dex_file, klass->GetVirtualMethod(i, image_pointer_size_)); 3229 } 3230} 3231 3232void ClassLinker::ResolveMethodExceptionHandlerTypes(const DexFile& dex_file, 3233 ArtMethod* method) { 3234 // similar to DexVerifier::ScanTryCatchBlocks and dex2oat's ResolveExceptionsForMethod. 3235 const DexFile::CodeItem* code_item = dex_file.GetCodeItem(method->GetCodeItemOffset()); 3236 if (code_item == nullptr) { 3237 return; // native or abstract method 3238 } 3239 if (code_item->tries_size_ == 0) { 3240 return; // nothing to process 3241 } 3242 const uint8_t* handlers_ptr = DexFile::GetCatchHandlerData(*code_item, 0); 3243 uint32_t handlers_size = DecodeUnsignedLeb128(&handlers_ptr); 3244 ClassLinker* linker = Runtime::Current()->GetClassLinker(); 3245 for (uint32_t idx = 0; idx < handlers_size; idx++) { 3246 CatchHandlerIterator iterator(handlers_ptr); 3247 for (; iterator.HasNext(); iterator.Next()) { 3248 // Ensure exception types are resolved so that they don't need resolution to be delivered, 3249 // unresolved exception types will be ignored by exception delivery 3250 if (iterator.GetHandlerTypeIndex() != DexFile::kDexNoIndex16) { 3251 mirror::Class* exception_type = linker->ResolveType(iterator.GetHandlerTypeIndex(), method); 3252 if (exception_type == nullptr) { 3253 DCHECK(Thread::Current()->IsExceptionPending()); 3254 Thread::Current()->ClearException(); 3255 } 3256 } 3257 } 3258 handlers_ptr = iterator.EndDataPointer(); 3259 } 3260} 3261 3262mirror::Class* ClassLinker::CreateProxyClass(ScopedObjectAccessAlreadyRunnable& soa, jstring name, 3263 jobjectArray interfaces, jobject loader, 3264 jobjectArray methods, jobjectArray throws) { 3265 Thread* self = soa.Self(); 3266 StackHandleScope<10> hs(self); 3267 MutableHandle<mirror::Class> klass(hs.NewHandle( 3268 AllocClass(self, GetClassRoot(kJavaLangClass), sizeof(mirror::Class)))); 3269 if (klass.Get() == nullptr) { 3270 CHECK(self->IsExceptionPending()); // OOME. 3271 return nullptr; 3272 } 3273 DCHECK(klass->GetClass() != nullptr); 3274 klass->SetObjectSize(sizeof(mirror::Proxy)); 3275 // Set the class access flags incl. preverified, so we do not try to set the flag on the methods. 3276 klass->SetAccessFlags(kAccClassIsProxy | kAccPublic | kAccFinal | kAccPreverified); 3277 klass->SetClassLoader(soa.Decode<mirror::ClassLoader*>(loader)); 3278 DCHECK_EQ(klass->GetPrimitiveType(), Primitive::kPrimNot); 3279 klass->SetName(soa.Decode<mirror::String*>(name)); 3280 klass->SetDexCache(GetClassRoot(kJavaLangReflectProxy)->GetDexCache()); 3281 mirror::Class::SetStatus(klass, mirror::Class::kStatusIdx, self); 3282 std::string descriptor(GetDescriptorForProxy(klass.Get())); 3283 size_t hash = ComputeModifiedUtf8Hash(descriptor.c_str()); 3284 3285 // Insert the class before loading the fields as the field roots 3286 // (ArtField::declaring_class_) are only visited from the class 3287 // table. There can't be any suspend points between inserting the 3288 // class and setting the field arrays below. 3289 mirror::Class* existing = InsertClass(descriptor.c_str(), klass.Get(), hash); 3290 CHECK(existing == nullptr); 3291 3292 // Instance fields are inherited, but we add a couple of static fields... 3293 const size_t num_fields = 2; 3294 ArtField* sfields = AllocArtFieldArray(self, num_fields); 3295 klass->SetSFields(sfields); 3296 klass->SetNumStaticFields(num_fields); 3297 3298 // 1. Create a static field 'interfaces' that holds the _declared_ interfaces implemented by 3299 // our proxy, so Class.getInterfaces doesn't return the flattened set. 3300 ArtField* interfaces_sfield = &sfields[0]; 3301 interfaces_sfield->SetDexFieldIndex(0); 3302 interfaces_sfield->SetDeclaringClass(klass.Get()); 3303 interfaces_sfield->SetAccessFlags(kAccStatic | kAccPublic | kAccFinal); 3304 3305 // 2. Create a static field 'throws' that holds exceptions thrown by our methods. 3306 ArtField* throws_sfield = &sfields[1]; 3307 throws_sfield->SetDexFieldIndex(1); 3308 throws_sfield->SetDeclaringClass(klass.Get()); 3309 throws_sfield->SetAccessFlags(kAccStatic | kAccPublic | kAccFinal); 3310 3311 // Proxies have 1 direct method, the constructor 3312 auto* directs = AllocArtMethodArray(self, 1); 3313 // Currently AllocArtMethodArray cannot return null, but the OOM logic is left there in case we 3314 // want to throw OOM in the future. 3315 if (UNLIKELY(directs == nullptr)) { 3316 self->AssertPendingOOMException(); 3317 return nullptr; 3318 } 3319 klass->SetDirectMethodsPtr(directs); 3320 klass->SetNumDirectMethods(1u); 3321 CreateProxyConstructor(klass, klass->GetDirectMethodUnchecked(0, image_pointer_size_)); 3322 3323 // Create virtual method using specified prototypes. 3324 auto h_methods = hs.NewHandle(soa.Decode<mirror::ObjectArray<mirror::Method>*>(methods)); 3325 DCHECK_EQ(h_methods->GetClass(), mirror::Method::ArrayClass()) 3326 << PrettyClass(h_methods->GetClass()); 3327 const size_t num_virtual_methods = h_methods->GetLength(); 3328 auto* virtuals = AllocArtMethodArray(self, num_virtual_methods); 3329 // Currently AllocArtMethodArray cannot return null, but the OOM logic is left there in case we 3330 // want to throw OOM in the future. 3331 if (UNLIKELY(virtuals == nullptr)) { 3332 self->AssertPendingOOMException(); 3333 return nullptr; 3334 } 3335 klass->SetVirtualMethodsPtr(virtuals); 3336 klass->SetNumVirtualMethods(num_virtual_methods); 3337 for (size_t i = 0; i < num_virtual_methods; ++i) { 3338 auto* virtual_method = klass->GetVirtualMethodUnchecked(i, image_pointer_size_); 3339 auto* prototype = h_methods->Get(i)->GetArtMethod(); 3340 CreateProxyMethod(klass, prototype, virtual_method); 3341 DCHECK(virtual_method->GetDeclaringClass() != nullptr); 3342 DCHECK(prototype->GetDeclaringClass() != nullptr); 3343 } 3344 3345 // The super class is java.lang.reflect.Proxy 3346 klass->SetSuperClass(GetClassRoot(kJavaLangReflectProxy)); 3347 // Now effectively in the loaded state. 3348 mirror::Class::SetStatus(klass, mirror::Class::kStatusLoaded, self); 3349 self->AssertNoPendingException(); 3350 3351 MutableHandle<mirror::Class> new_class = hs.NewHandle<mirror::Class>(nullptr); 3352 { 3353 // Must hold lock on object when resolved. 3354 ObjectLock<mirror::Class> resolution_lock(self, klass); 3355 // Link the fields and virtual methods, creating vtable and iftables. 3356 // The new class will replace the old one in the class table. 3357 Handle<mirror::ObjectArray<mirror::Class>> h_interfaces( 3358 hs.NewHandle(soa.Decode<mirror::ObjectArray<mirror::Class>*>(interfaces))); 3359 if (!LinkClass(self, descriptor.c_str(), klass, h_interfaces, &new_class)) { 3360 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3361 return nullptr; 3362 } 3363 } 3364 CHECK(klass->IsRetired()); 3365 CHECK_NE(klass.Get(), new_class.Get()); 3366 klass.Assign(new_class.Get()); 3367 3368 CHECK_EQ(interfaces_sfield->GetDeclaringClass(), klass.Get()); 3369 interfaces_sfield->SetObject<false>(klass.Get(), 3370 soa.Decode<mirror::ObjectArray<mirror::Class>*>(interfaces)); 3371 CHECK_EQ(throws_sfield->GetDeclaringClass(), klass.Get()); 3372 throws_sfield->SetObject<false>(klass.Get(), 3373 soa.Decode<mirror::ObjectArray<mirror::ObjectArray<mirror::Class> >*>(throws)); 3374 3375 { 3376 // Lock on klass is released. Lock new class object. 3377 ObjectLock<mirror::Class> initialization_lock(self, klass); 3378 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitialized, self); 3379 } 3380 3381 // sanity checks 3382 if (kIsDebugBuild) { 3383 CHECK(klass->GetIFields() == nullptr); 3384 CheckProxyConstructor(klass->GetDirectMethod(0, image_pointer_size_)); 3385 3386 for (size_t i = 0; i < num_virtual_methods; ++i) { 3387 auto* virtual_method = klass->GetVirtualMethodUnchecked(i, image_pointer_size_); 3388 auto* prototype = h_methods->Get(i++)->GetArtMethod(); 3389 CheckProxyMethod(virtual_method, prototype); 3390 } 3391 3392 StackHandleScope<1> hs2(self); 3393 Handle<mirror::String> decoded_name = hs2.NewHandle(soa.Decode<mirror::String*>(name)); 3394 std::string interfaces_field_name(StringPrintf("java.lang.Class[] %s.interfaces", 3395 decoded_name->ToModifiedUtf8().c_str())); 3396 CHECK_EQ(PrettyField(klass->GetStaticField(0)), interfaces_field_name); 3397 3398 std::string throws_field_name(StringPrintf("java.lang.Class[][] %s.throws", 3399 decoded_name->ToModifiedUtf8().c_str())); 3400 CHECK_EQ(PrettyField(klass->GetStaticField(1)), throws_field_name); 3401 3402 CHECK_EQ(klass.Get()->GetInterfaces(), 3403 soa.Decode<mirror::ObjectArray<mirror::Class>*>(interfaces)); 3404 CHECK_EQ(klass.Get()->GetThrows(), 3405 soa.Decode<mirror::ObjectArray<mirror::ObjectArray<mirror::Class>>*>(throws)); 3406 } 3407 return klass.Get(); 3408} 3409 3410std::string ClassLinker::GetDescriptorForProxy(mirror::Class* proxy_class) { 3411 DCHECK(proxy_class->IsProxyClass()); 3412 mirror::String* name = proxy_class->GetName(); 3413 DCHECK(name != nullptr); 3414 return DotToDescriptor(name->ToModifiedUtf8().c_str()); 3415} 3416 3417ArtMethod* ClassLinker::FindMethodForProxy(mirror::Class* proxy_class, 3418 ArtMethod* proxy_method) { 3419 DCHECK(proxy_class->IsProxyClass()); 3420 DCHECK(proxy_method->IsProxyMethod()); 3421 { 3422 ReaderMutexLock mu(Thread::Current(), dex_lock_); 3423 // Locate the dex cache of the original interface/Object 3424 for (const GcRoot<mirror::DexCache>& root : dex_caches_) { 3425 auto* dex_cache = root.Read(); 3426 if (proxy_method->HasSameDexCacheResolvedTypes(dex_cache->GetResolvedTypes())) { 3427 ArtMethod* resolved_method = dex_cache->GetResolvedMethod( 3428 proxy_method->GetDexMethodIndex(), image_pointer_size_); 3429 CHECK(resolved_method != nullptr); 3430 return resolved_method; 3431 } 3432 } 3433 } 3434 LOG(FATAL) << "Didn't find dex cache for " << PrettyClass(proxy_class) << " " 3435 << PrettyMethod(proxy_method); 3436 UNREACHABLE(); 3437} 3438 3439void ClassLinker::CreateProxyConstructor(Handle<mirror::Class> klass, ArtMethod* out) { 3440 // Create constructor for Proxy that must initialize the method. 3441 CHECK_EQ(GetClassRoot(kJavaLangReflectProxy)->NumDirectMethods(), 16u); 3442 ArtMethod* proxy_constructor = GetClassRoot(kJavaLangReflectProxy)->GetDirectMethodUnchecked( 3443 2, image_pointer_size_); 3444 // Ensure constructor is in dex cache so that we can use the dex cache to look up the overridden 3445 // constructor method. 3446 GetClassRoot(kJavaLangReflectProxy)->GetDexCache()->SetResolvedMethod( 3447 proxy_constructor->GetDexMethodIndex(), proxy_constructor, image_pointer_size_); 3448 // Clone the existing constructor of Proxy (our constructor would just invoke it so steal its 3449 // code_ too) 3450 DCHECK(out != nullptr); 3451 out->CopyFrom(proxy_constructor, image_pointer_size_); 3452 // Make this constructor public and fix the class to be our Proxy version 3453 out->SetAccessFlags((out->GetAccessFlags() & ~kAccProtected) | kAccPublic); 3454 out->SetDeclaringClass(klass.Get()); 3455} 3456 3457void ClassLinker::CheckProxyConstructor(ArtMethod* constructor) const { 3458 CHECK(constructor->IsConstructor()); 3459 auto* np = constructor->GetInterfaceMethodIfProxy(image_pointer_size_); 3460 CHECK_STREQ(np->GetName(), "<init>"); 3461 CHECK_STREQ(np->GetSignature().ToString().c_str(), "(Ljava/lang/reflect/InvocationHandler;)V"); 3462 DCHECK(constructor->IsPublic()); 3463} 3464 3465void ClassLinker::CreateProxyMethod(Handle<mirror::Class> klass, ArtMethod* prototype, 3466 ArtMethod* out) { 3467 // Ensure prototype is in dex cache so that we can use the dex cache to look up the overridden 3468 // prototype method 3469 auto* dex_cache = prototype->GetDeclaringClass()->GetDexCache(); 3470 // Avoid dirtying the dex cache unless we need to. 3471 if (dex_cache->GetResolvedMethod(prototype->GetDexMethodIndex(), image_pointer_size_) != 3472 prototype) { 3473 dex_cache->SetResolvedMethod( 3474 prototype->GetDexMethodIndex(), prototype, image_pointer_size_); 3475 } 3476 // We steal everything from the prototype (such as DexCache, invoke stub, etc.) then specialize 3477 // as necessary 3478 DCHECK(out != nullptr); 3479 out->CopyFrom(prototype, image_pointer_size_); 3480 3481 // Set class to be the concrete proxy class and clear the abstract flag, modify exceptions to 3482 // the intersection of throw exceptions as defined in Proxy 3483 out->SetDeclaringClass(klass.Get()); 3484 out->SetAccessFlags((out->GetAccessFlags() & ~kAccAbstract) | kAccFinal); 3485 3486 // At runtime the method looks like a reference and argument saving method, clone the code 3487 // related parameters from this method. 3488 out->SetEntryPointFromQuickCompiledCode(GetQuickProxyInvokeHandler()); 3489 out->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 3490} 3491 3492void ClassLinker::CheckProxyMethod(ArtMethod* method, ArtMethod* prototype) const { 3493 // Basic sanity 3494 CHECK(!prototype->IsFinal()); 3495 CHECK(method->IsFinal()); 3496 CHECK(!method->IsAbstract()); 3497 3498 // The proxy method doesn't have its own dex cache or dex file and so it steals those of its 3499 // interface prototype. The exception to this are Constructors and the Class of the Proxy itself. 3500 CHECK(prototype->HasSameDexCacheResolvedMethods(method)); 3501 CHECK(prototype->HasSameDexCacheResolvedTypes(method)); 3502 auto* np = method->GetInterfaceMethodIfProxy(image_pointer_size_); 3503 CHECK_EQ(prototype->GetDeclaringClass()->GetDexCache(), np->GetDexCache()); 3504 CHECK_EQ(prototype->GetDexMethodIndex(), method->GetDexMethodIndex()); 3505 3506 CHECK_STREQ(np->GetName(), prototype->GetName()); 3507 CHECK_STREQ(np->GetShorty(), prototype->GetShorty()); 3508 // More complex sanity - via dex cache 3509 CHECK_EQ(np->GetReturnType(), prototype->GetReturnType()); 3510} 3511 3512bool ClassLinker::CanWeInitializeClass(mirror::Class* klass, bool can_init_statics, 3513 bool can_init_parents) { 3514 if (can_init_statics && can_init_parents) { 3515 return true; 3516 } 3517 if (!can_init_statics) { 3518 // Check if there's a class initializer. 3519 ArtMethod* clinit = klass->FindClassInitializer(image_pointer_size_); 3520 if (clinit != nullptr) { 3521 return false; 3522 } 3523 // Check if there are encoded static values needing initialization. 3524 if (klass->NumStaticFields() != 0) { 3525 const DexFile::ClassDef* dex_class_def = klass->GetClassDef(); 3526 DCHECK(dex_class_def != nullptr); 3527 if (dex_class_def->static_values_off_ != 0) { 3528 return false; 3529 } 3530 } 3531 } 3532 if (klass->IsInterface() || !klass->HasSuperClass()) { 3533 return true; 3534 } 3535 mirror::Class* super_class = klass->GetSuperClass(); 3536 if (!can_init_parents && !super_class->IsInitialized()) { 3537 return false; 3538 } 3539 return CanWeInitializeClass(super_class, can_init_statics, can_init_parents); 3540} 3541 3542bool ClassLinker::InitializeClass(Thread* self, Handle<mirror::Class> klass, 3543 bool can_init_statics, bool can_init_parents) { 3544 // see JLS 3rd edition, 12.4.2 "Detailed Initialization Procedure" for the locking protocol 3545 3546 // Are we already initialized and therefore done? 3547 // Note: we differ from the JLS here as we don't do this under the lock, this is benign as 3548 // an initialized class will never change its state. 3549 if (klass->IsInitialized()) { 3550 return true; 3551 } 3552 3553 // Fast fail if initialization requires a full runtime. Not part of the JLS. 3554 if (!CanWeInitializeClass(klass.Get(), can_init_statics, can_init_parents)) { 3555 return false; 3556 } 3557 3558 self->AllowThreadSuspension(); 3559 uint64_t t0; 3560 { 3561 ObjectLock<mirror::Class> lock(self, klass); 3562 3563 // Re-check under the lock in case another thread initialized ahead of us. 3564 if (klass->IsInitialized()) { 3565 return true; 3566 } 3567 3568 // Was the class already found to be erroneous? Done under the lock to match the JLS. 3569 if (klass->IsErroneous()) { 3570 ThrowEarlierClassFailure(klass.Get()); 3571 VlogClassInitializationFailure(klass); 3572 return false; 3573 } 3574 3575 CHECK(klass->IsResolved()) << PrettyClass(klass.Get()) << ": state=" << klass->GetStatus(); 3576 3577 if (!klass->IsVerified()) { 3578 VerifyClass(self, klass); 3579 if (!klass->IsVerified()) { 3580 // We failed to verify, expect either the klass to be erroneous or verification failed at 3581 // compile time. 3582 if (klass->IsErroneous()) { 3583 CHECK(self->IsExceptionPending()); 3584 VlogClassInitializationFailure(klass); 3585 } else { 3586 CHECK(Runtime::Current()->IsAotCompiler()); 3587 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime); 3588 } 3589 return false; 3590 } else { 3591 self->AssertNoPendingException(); 3592 } 3593 } 3594 3595 // If the class is kStatusInitializing, either this thread is 3596 // initializing higher up the stack or another thread has beat us 3597 // to initializing and we need to wait. Either way, this 3598 // invocation of InitializeClass will not be responsible for 3599 // running <clinit> and will return. 3600 if (klass->GetStatus() == mirror::Class::kStatusInitializing) { 3601 // Could have got an exception during verification. 3602 if (self->IsExceptionPending()) { 3603 VlogClassInitializationFailure(klass); 3604 return false; 3605 } 3606 // We caught somebody else in the act; was it us? 3607 if (klass->GetClinitThreadId() == self->GetTid()) { 3608 // Yes. That's fine. Return so we can continue initializing. 3609 return true; 3610 } 3611 // No. That's fine. Wait for another thread to finish initializing. 3612 return WaitForInitializeClass(klass, self, lock); 3613 } 3614 3615 if (!ValidateSuperClassDescriptors(klass)) { 3616 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3617 return false; 3618 } 3619 self->AllowThreadSuspension(); 3620 3621 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusVerified) << PrettyClass(klass.Get()); 3622 3623 // From here out other threads may observe that we're initializing and so changes of state 3624 // require the a notification. 3625 klass->SetClinitThreadId(self->GetTid()); 3626 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitializing, self); 3627 3628 t0 = NanoTime(); 3629 } 3630 3631 // Initialize super classes, must be done while initializing for the JLS. 3632 if (!klass->IsInterface() && klass->HasSuperClass()) { 3633 mirror::Class* super_class = klass->GetSuperClass(); 3634 if (!super_class->IsInitialized()) { 3635 CHECK(!super_class->IsInterface()); 3636 CHECK(can_init_parents); 3637 StackHandleScope<1> hs(self); 3638 Handle<mirror::Class> handle_scope_super(hs.NewHandle(super_class)); 3639 bool super_initialized = InitializeClass(self, handle_scope_super, can_init_statics, true); 3640 if (!super_initialized) { 3641 // The super class was verified ahead of entering initializing, we should only be here if 3642 // the super class became erroneous due to initialization. 3643 CHECK(handle_scope_super->IsErroneous() && self->IsExceptionPending()) 3644 << "Super class initialization failed for " 3645 << PrettyDescriptor(handle_scope_super.Get()) 3646 << " that has unexpected status " << handle_scope_super->GetStatus() 3647 << "\nPending exception:\n" 3648 << (self->GetException() != nullptr ? self->GetException()->Dump() : ""); 3649 ObjectLock<mirror::Class> lock(self, klass); 3650 // Initialization failed because the super-class is erroneous. 3651 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3652 return false; 3653 } 3654 } 3655 } 3656 3657 const size_t num_static_fields = klass->NumStaticFields(); 3658 if (num_static_fields > 0) { 3659 const DexFile::ClassDef* dex_class_def = klass->GetClassDef(); 3660 CHECK(dex_class_def != nullptr); 3661 const DexFile& dex_file = klass->GetDexFile(); 3662 StackHandleScope<3> hs(self); 3663 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(klass->GetClassLoader())); 3664 Handle<mirror::DexCache> dex_cache(hs.NewHandle(klass->GetDexCache())); 3665 3666 // Eagerly fill in static fields so that the we don't have to do as many expensive 3667 // Class::FindStaticField in ResolveField. 3668 for (size_t i = 0; i < num_static_fields; ++i) { 3669 ArtField* field = klass->GetStaticField(i); 3670 const uint32_t field_idx = field->GetDexFieldIndex(); 3671 ArtField* resolved_field = dex_cache->GetResolvedField(field_idx, image_pointer_size_); 3672 if (resolved_field == nullptr) { 3673 dex_cache->SetResolvedField(field_idx, field, image_pointer_size_); 3674 } else { 3675 DCHECK_EQ(field, resolved_field); 3676 } 3677 } 3678 3679 EncodedStaticFieldValueIterator value_it(dex_file, &dex_cache, &class_loader, 3680 this, *dex_class_def); 3681 const uint8_t* class_data = dex_file.GetClassData(*dex_class_def); 3682 ClassDataItemIterator field_it(dex_file, class_data); 3683 if (value_it.HasNext()) { 3684 DCHECK(field_it.HasNextStaticField()); 3685 CHECK(can_init_statics); 3686 for ( ; value_it.HasNext(); value_it.Next(), field_it.Next()) { 3687 ArtField* field = ResolveField( 3688 dex_file, field_it.GetMemberIndex(), dex_cache, class_loader, true); 3689 if (Runtime::Current()->IsActiveTransaction()) { 3690 value_it.ReadValueToField<true>(field); 3691 } else { 3692 value_it.ReadValueToField<false>(field); 3693 } 3694 DCHECK(!value_it.HasNext() || field_it.HasNextStaticField()); 3695 } 3696 } 3697 } 3698 3699 ArtMethod* clinit = klass->FindClassInitializer(image_pointer_size_); 3700 if (clinit != nullptr) { 3701 CHECK(can_init_statics); 3702 JValue result; 3703 clinit->Invoke(self, nullptr, 0, &result, "V"); 3704 } 3705 3706 self->AllowThreadSuspension(); 3707 uint64_t t1 = NanoTime(); 3708 3709 bool success = true; 3710 { 3711 ObjectLock<mirror::Class> lock(self, klass); 3712 3713 if (self->IsExceptionPending()) { 3714 WrapExceptionInInitializer(klass); 3715 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3716 success = false; 3717 } else if (Runtime::Current()->IsTransactionAborted()) { 3718 // The exception thrown when the transaction aborted has been caught and cleared 3719 // so we need to throw it again now. 3720 VLOG(compiler) << "Return from class initializer of " << PrettyDescriptor(klass.Get()) 3721 << " without exception while transaction was aborted: re-throw it now."; 3722 Runtime::Current()->ThrowTransactionAbortError(self); 3723 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3724 success = false; 3725 } else { 3726 RuntimeStats* global_stats = Runtime::Current()->GetStats(); 3727 RuntimeStats* thread_stats = self->GetStats(); 3728 ++global_stats->class_init_count; 3729 ++thread_stats->class_init_count; 3730 global_stats->class_init_time_ns += (t1 - t0); 3731 thread_stats->class_init_time_ns += (t1 - t0); 3732 // Set the class as initialized except if failed to initialize static fields. 3733 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitialized, self); 3734 if (VLOG_IS_ON(class_linker)) { 3735 std::string temp; 3736 LOG(INFO) << "Initialized class " << klass->GetDescriptor(&temp) << " from " << 3737 klass->GetLocation(); 3738 } 3739 // Opportunistically set static method trampolines to their destination. 3740 FixupStaticTrampolines(klass.Get()); 3741 } 3742 } 3743 return success; 3744} 3745 3746bool ClassLinker::WaitForInitializeClass(Handle<mirror::Class> klass, Thread* self, 3747 ObjectLock<mirror::Class>& lock) 3748 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3749 while (true) { 3750 self->AssertNoPendingException(); 3751 CHECK(!klass->IsInitialized()); 3752 lock.WaitIgnoringInterrupts(); 3753 3754 // When we wake up, repeat the test for init-in-progress. If 3755 // there's an exception pending (only possible if 3756 // we were not using WaitIgnoringInterrupts), bail out. 3757 if (self->IsExceptionPending()) { 3758 WrapExceptionInInitializer(klass); 3759 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3760 return false; 3761 } 3762 // Spurious wakeup? Go back to waiting. 3763 if (klass->GetStatus() == mirror::Class::kStatusInitializing) { 3764 continue; 3765 } 3766 if (klass->GetStatus() == mirror::Class::kStatusVerified && 3767 Runtime::Current()->IsAotCompiler()) { 3768 // Compile time initialization failed. 3769 return false; 3770 } 3771 if (klass->IsErroneous()) { 3772 // The caller wants an exception, but it was thrown in a 3773 // different thread. Synthesize one here. 3774 ThrowNoClassDefFoundError("<clinit> failed for class %s; see exception in other thread", 3775 PrettyDescriptor(klass.Get()).c_str()); 3776 VlogClassInitializationFailure(klass); 3777 return false; 3778 } 3779 if (klass->IsInitialized()) { 3780 return true; 3781 } 3782 LOG(FATAL) << "Unexpected class status. " << PrettyClass(klass.Get()) << " is " 3783 << klass->GetStatus(); 3784 } 3785 UNREACHABLE(); 3786} 3787 3788static void ThrowSignatureCheckResolveReturnTypeException(Handle<mirror::Class> klass, 3789 Handle<mirror::Class> super_klass, 3790 ArtMethod* method, 3791 ArtMethod* m) 3792 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3793 DCHECK(Thread::Current()->IsExceptionPending()); 3794 DCHECK(!m->IsProxyMethod()); 3795 const DexFile* dex_file = m->GetDexFile(); 3796 const DexFile::MethodId& method_id = dex_file->GetMethodId(m->GetDexMethodIndex()); 3797 const DexFile::ProtoId& proto_id = dex_file->GetMethodPrototype(method_id); 3798 uint16_t return_type_idx = proto_id.return_type_idx_; 3799 std::string return_type = PrettyType(return_type_idx, *dex_file); 3800 std::string class_loader = PrettyTypeOf(m->GetDeclaringClass()->GetClassLoader()); 3801 ThrowWrappedLinkageError(klass.Get(), 3802 "While checking class %s method %s signature against %s %s: " 3803 "Failed to resolve return type %s with %s", 3804 PrettyDescriptor(klass.Get()).c_str(), 3805 PrettyMethod(method).c_str(), 3806 super_klass->IsInterface() ? "interface" : "superclass", 3807 PrettyDescriptor(super_klass.Get()).c_str(), 3808 return_type.c_str(), class_loader.c_str()); 3809} 3810 3811static void ThrowSignatureCheckResolveArgException(Handle<mirror::Class> klass, 3812 Handle<mirror::Class> super_klass, 3813 ArtMethod* method, 3814 ArtMethod* m, 3815 uint32_t index, uint32_t arg_type_idx) 3816 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3817 DCHECK(Thread::Current()->IsExceptionPending()); 3818 DCHECK(!m->IsProxyMethod()); 3819 const DexFile* dex_file = m->GetDexFile(); 3820 std::string arg_type = PrettyType(arg_type_idx, *dex_file); 3821 std::string class_loader = PrettyTypeOf(m->GetDeclaringClass()->GetClassLoader()); 3822 ThrowWrappedLinkageError(klass.Get(), 3823 "While checking class %s method %s signature against %s %s: " 3824 "Failed to resolve arg %u type %s with %s", 3825 PrettyDescriptor(klass.Get()).c_str(), 3826 PrettyMethod(method).c_str(), 3827 super_klass->IsInterface() ? "interface" : "superclass", 3828 PrettyDescriptor(super_klass.Get()).c_str(), 3829 index, arg_type.c_str(), class_loader.c_str()); 3830} 3831 3832static void ThrowSignatureMismatch(Handle<mirror::Class> klass, 3833 Handle<mirror::Class> super_klass, 3834 ArtMethod* method, 3835 const std::string& error_msg) 3836 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3837 ThrowLinkageError(klass.Get(), 3838 "Class %s method %s resolves differently in %s %s: %s", 3839 PrettyDescriptor(klass.Get()).c_str(), 3840 PrettyMethod(method).c_str(), 3841 super_klass->IsInterface() ? "interface" : "superclass", 3842 PrettyDescriptor(super_klass.Get()).c_str(), 3843 error_msg.c_str()); 3844} 3845 3846static bool HasSameSignatureWithDifferentClassLoaders(Thread* self, 3847 Handle<mirror::Class> klass, 3848 Handle<mirror::Class> super_klass, 3849 ArtMethod* method1, 3850 ArtMethod* method2) 3851 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3852 { 3853 StackHandleScope<1> hs(self); 3854 Handle<mirror::Class> return_type(hs.NewHandle(method1->GetReturnType())); 3855 if (UNLIKELY(return_type.Get() == nullptr)) { 3856 ThrowSignatureCheckResolveReturnTypeException(klass, super_klass, method1, method1); 3857 return false; 3858 } 3859 mirror::Class* other_return_type = method2->GetReturnType(); 3860 if (UNLIKELY(other_return_type == nullptr)) { 3861 ThrowSignatureCheckResolveReturnTypeException(klass, super_klass, method1, method2); 3862 return false; 3863 } 3864 if (UNLIKELY(other_return_type != return_type.Get())) { 3865 ThrowSignatureMismatch(klass, super_klass, method1, 3866 StringPrintf("Return types mismatch: %s(%p) vs %s(%p)", 3867 PrettyClassAndClassLoader(return_type.Get()).c_str(), 3868 return_type.Get(), 3869 PrettyClassAndClassLoader(other_return_type).c_str(), 3870 other_return_type)); 3871 return false; 3872 } 3873 } 3874 const DexFile::TypeList* types1 = method1->GetParameterTypeList(); 3875 const DexFile::TypeList* types2 = method2->GetParameterTypeList(); 3876 if (types1 == nullptr) { 3877 if (types2 != nullptr && types2->Size() != 0) { 3878 ThrowSignatureMismatch(klass, super_klass, method1, 3879 StringPrintf("Type list mismatch with %s", 3880 PrettyMethod(method2, true).c_str())); 3881 return false; 3882 } 3883 return true; 3884 } else if (UNLIKELY(types2 == nullptr)) { 3885 if (types1->Size() != 0) { 3886 ThrowSignatureMismatch(klass, super_klass, method1, 3887 StringPrintf("Type list mismatch with %s", 3888 PrettyMethod(method2, true).c_str())); 3889 return false; 3890 } 3891 return true; 3892 } 3893 uint32_t num_types = types1->Size(); 3894 if (UNLIKELY(num_types != types2->Size())) { 3895 ThrowSignatureMismatch(klass, super_klass, method1, 3896 StringPrintf("Type list mismatch with %s", 3897 PrettyMethod(method2, true).c_str())); 3898 return false; 3899 } 3900 for (uint32_t i = 0; i < num_types; ++i) { 3901 StackHandleScope<1> hs(self); 3902 uint32_t param_type_idx = types1->GetTypeItem(i).type_idx_; 3903 Handle<mirror::Class> param_type(hs.NewHandle( 3904 method1->GetClassFromTypeIndex(param_type_idx, true))); 3905 if (UNLIKELY(param_type.Get() == nullptr)) { 3906 ThrowSignatureCheckResolveArgException(klass, super_klass, method1, 3907 method1, i, param_type_idx); 3908 return false; 3909 } 3910 uint32_t other_param_type_idx = types2->GetTypeItem(i).type_idx_; 3911 mirror::Class* other_param_type = 3912 method2->GetClassFromTypeIndex(other_param_type_idx, true); 3913 if (UNLIKELY(other_param_type == nullptr)) { 3914 ThrowSignatureCheckResolveArgException(klass, super_klass, method1, 3915 method2, i, other_param_type_idx); 3916 return false; 3917 } 3918 if (UNLIKELY(param_type.Get() != other_param_type)) { 3919 ThrowSignatureMismatch(klass, super_klass, method1, 3920 StringPrintf("Parameter %u type mismatch: %s(%p) vs %s(%p)", 3921 i, 3922 PrettyClassAndClassLoader(param_type.Get()).c_str(), 3923 param_type.Get(), 3924 PrettyClassAndClassLoader(other_param_type).c_str(), 3925 other_param_type)); 3926 return false; 3927 } 3928 } 3929 return true; 3930} 3931 3932 3933bool ClassLinker::ValidateSuperClassDescriptors(Handle<mirror::Class> klass) { 3934 if (klass->IsInterface()) { 3935 return true; 3936 } 3937 // Begin with the methods local to the superclass. 3938 Thread* self = Thread::Current(); 3939 StackHandleScope<1> hs(self); 3940 MutableHandle<mirror::Class> super_klass(hs.NewHandle<mirror::Class>(nullptr)); 3941 if (klass->HasSuperClass() && 3942 klass->GetClassLoader() != klass->GetSuperClass()->GetClassLoader()) { 3943 super_klass.Assign(klass->GetSuperClass()); 3944 for (int i = klass->GetSuperClass()->GetVTableLength() - 1; i >= 0; --i) { 3945 auto* m = klass->GetVTableEntry(i, image_pointer_size_); 3946 auto* super_m = klass->GetSuperClass()->GetVTableEntry(i, image_pointer_size_); 3947 if (m != super_m) { 3948 if (UNLIKELY(!HasSameSignatureWithDifferentClassLoaders(self, klass, super_klass, 3949 m, super_m))) { 3950 self->AssertPendingException(); 3951 return false; 3952 } 3953 } 3954 } 3955 } 3956 for (int32_t i = 0; i < klass->GetIfTableCount(); ++i) { 3957 super_klass.Assign(klass->GetIfTable()->GetInterface(i)); 3958 if (klass->GetClassLoader() != super_klass->GetClassLoader()) { 3959 uint32_t num_methods = super_klass->NumVirtualMethods(); 3960 for (uint32_t j = 0; j < num_methods; ++j) { 3961 auto* m = klass->GetIfTable()->GetMethodArray(i)->GetElementPtrSize<ArtMethod*>( 3962 j, image_pointer_size_); 3963 auto* super_m = super_klass->GetVirtualMethod(j, image_pointer_size_); 3964 if (m != super_m) { 3965 if (UNLIKELY(!HasSameSignatureWithDifferentClassLoaders(self, klass, super_klass, 3966 m, super_m))) { 3967 self->AssertPendingException(); 3968 return false; 3969 } 3970 } 3971 } 3972 } 3973 } 3974 return true; 3975} 3976 3977bool ClassLinker::EnsureInitialized(Thread* self, Handle<mirror::Class> c, bool can_init_fields, 3978 bool can_init_parents) { 3979 DCHECK(c.Get() != nullptr); 3980 if (c->IsInitialized()) { 3981 EnsurePreverifiedMethods(c); 3982 return true; 3983 } 3984 const bool success = InitializeClass(self, c, can_init_fields, can_init_parents); 3985 if (!success) { 3986 if (can_init_fields && can_init_parents) { 3987 CHECK(self->IsExceptionPending()) << PrettyClass(c.Get()); 3988 } 3989 } else { 3990 self->AssertNoPendingException(); 3991 } 3992 return success; 3993} 3994 3995void ClassLinker::FixupTemporaryDeclaringClass(mirror::Class* temp_class, 3996 mirror::Class* new_class) { 3997 ArtField* fields = new_class->GetIFields(); 3998 DCHECK_EQ(temp_class->NumInstanceFields(), new_class->NumInstanceFields()); 3999 for (size_t i = 0, count = new_class->NumInstanceFields(); i < count; i++) { 4000 if (fields[i].GetDeclaringClass() == temp_class) { 4001 fields[i].SetDeclaringClass(new_class); 4002 } 4003 } 4004 4005 fields = new_class->GetSFields(); 4006 DCHECK_EQ(temp_class->NumStaticFields(), new_class->NumStaticFields()); 4007 for (size_t i = 0, count = new_class->NumStaticFields(); i < count; i++) { 4008 if (fields[i].GetDeclaringClass() == temp_class) { 4009 fields[i].SetDeclaringClass(new_class); 4010 } 4011 } 4012 4013 DCHECK_EQ(temp_class->NumDirectMethods(), new_class->NumDirectMethods()); 4014 for (auto& method : new_class->GetDirectMethods(image_pointer_size_)) { 4015 if (method.GetDeclaringClass() == temp_class) { 4016 method.SetDeclaringClass(new_class); 4017 } 4018 } 4019 4020 DCHECK_EQ(temp_class->NumVirtualMethods(), new_class->NumVirtualMethods()); 4021 for (auto& method : new_class->GetVirtualMethods(image_pointer_size_)) { 4022 if (method.GetDeclaringClass() == temp_class) { 4023 method.SetDeclaringClass(new_class); 4024 } 4025 } 4026} 4027 4028bool ClassLinker::LinkClass(Thread* self, const char* descriptor, Handle<mirror::Class> klass, 4029 Handle<mirror::ObjectArray<mirror::Class>> interfaces, 4030 MutableHandle<mirror::Class>* h_new_class_out) { 4031 CHECK_EQ(mirror::Class::kStatusLoaded, klass->GetStatus()); 4032 4033 if (!LinkSuperClass(klass)) { 4034 return false; 4035 } 4036 ArtMethod* imt[mirror::Class::kImtSize]; 4037 std::fill_n(imt, arraysize(imt), Runtime::Current()->GetImtUnimplementedMethod()); 4038 if (!LinkMethods(self, klass, interfaces, imt)) { 4039 return false; 4040 } 4041 if (!LinkInstanceFields(self, klass)) { 4042 return false; 4043 } 4044 size_t class_size; 4045 if (!LinkStaticFields(self, klass, &class_size)) { 4046 return false; 4047 } 4048 CreateReferenceInstanceOffsets(klass); 4049 CHECK_EQ(mirror::Class::kStatusLoaded, klass->GetStatus()); 4050 4051 if (!klass->IsTemp() || (!init_done_ && klass->GetClassSize() == class_size)) { 4052 // We don't need to retire this class as it has no embedded tables or it was created the 4053 // correct size during class linker initialization. 4054 CHECK_EQ(klass->GetClassSize(), class_size) << PrettyDescriptor(klass.Get()); 4055 4056 if (klass->ShouldHaveEmbeddedImtAndVTable()) { 4057 klass->PopulateEmbeddedImtAndVTable(imt, image_pointer_size_); 4058 } 4059 4060 // This will notify waiters on klass that saw the not yet resolved 4061 // class in the class_table_ during EnsureResolved. 4062 mirror::Class::SetStatus(klass, mirror::Class::kStatusResolved, self); 4063 h_new_class_out->Assign(klass.Get()); 4064 } else { 4065 CHECK(!klass->IsResolved()); 4066 // Retire the temporary class and create the correctly sized resolved class. 4067 StackHandleScope<1> hs(self); 4068 auto h_new_class = hs.NewHandle(klass->CopyOf(self, class_size, imt, image_pointer_size_)); 4069 if (UNLIKELY(h_new_class.Get() == nullptr)) { 4070 self->AssertPendingOOMException(); 4071 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 4072 return false; 4073 } 4074 4075 CHECK_EQ(h_new_class->GetClassSize(), class_size); 4076 ObjectLock<mirror::Class> lock(self, h_new_class); 4077 FixupTemporaryDeclaringClass(klass.Get(), h_new_class.Get()); 4078 mirror::Class* existing = UpdateClass(descriptor, h_new_class.Get(), 4079 ComputeModifiedUtf8Hash(descriptor)); 4080 CHECK(existing == nullptr || existing == klass.Get()); 4081 4082 // This will notify waiters on temp class that saw the not yet resolved class in the 4083 // class_table_ during EnsureResolved. 4084 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetired, self); 4085 4086 CHECK_EQ(h_new_class->GetStatus(), mirror::Class::kStatusResolving); 4087 // This will notify waiters on new_class that saw the not yet resolved 4088 // class in the class_table_ during EnsureResolved. 4089 mirror::Class::SetStatus(h_new_class, mirror::Class::kStatusResolved, self); 4090 // Return the new class. 4091 h_new_class_out->Assign(h_new_class.Get()); 4092 } 4093 return true; 4094} 4095 4096static void CountMethodsAndFields(ClassDataItemIterator& dex_data, 4097 size_t* virtual_methods, 4098 size_t* direct_methods, 4099 size_t* static_fields, 4100 size_t* instance_fields) { 4101 *virtual_methods = *direct_methods = *static_fields = *instance_fields = 0; 4102 4103 while (dex_data.HasNextStaticField()) { 4104 dex_data.Next(); 4105 (*static_fields)++; 4106 } 4107 while (dex_data.HasNextInstanceField()) { 4108 dex_data.Next(); 4109 (*instance_fields)++; 4110 } 4111 while (dex_data.HasNextDirectMethod()) { 4112 (*direct_methods)++; 4113 dex_data.Next(); 4114 } 4115 while (dex_data.HasNextVirtualMethod()) { 4116 (*virtual_methods)++; 4117 dex_data.Next(); 4118 } 4119 DCHECK(!dex_data.HasNext()); 4120} 4121 4122static void DumpClass(std::ostream& os, 4123 const DexFile& dex_file, const DexFile::ClassDef& dex_class_def, 4124 const char* suffix) { 4125 ClassDataItemIterator dex_data(dex_file, dex_file.GetClassData(dex_class_def)); 4126 os << dex_file.GetClassDescriptor(dex_class_def) << suffix << ":\n"; 4127 os << " Static fields:\n"; 4128 while (dex_data.HasNextStaticField()) { 4129 const DexFile::FieldId& id = dex_file.GetFieldId(dex_data.GetMemberIndex()); 4130 os << " " << dex_file.GetFieldTypeDescriptor(id) << " " << dex_file.GetFieldName(id) << "\n"; 4131 dex_data.Next(); 4132 } 4133 os << " Instance fields:\n"; 4134 while (dex_data.HasNextInstanceField()) { 4135 const DexFile::FieldId& id = dex_file.GetFieldId(dex_data.GetMemberIndex()); 4136 os << " " << dex_file.GetFieldTypeDescriptor(id) << " " << dex_file.GetFieldName(id) << "\n"; 4137 dex_data.Next(); 4138 } 4139 os << " Direct methods:\n"; 4140 while (dex_data.HasNextDirectMethod()) { 4141 const DexFile::MethodId& id = dex_file.GetMethodId(dex_data.GetMemberIndex()); 4142 os << " " << dex_file.GetMethodName(id) << dex_file.GetMethodSignature(id).ToString() << "\n"; 4143 dex_data.Next(); 4144 } 4145 os << " Virtual methods:\n"; 4146 while (dex_data.HasNextVirtualMethod()) { 4147 const DexFile::MethodId& id = dex_file.GetMethodId(dex_data.GetMemberIndex()); 4148 os << " " << dex_file.GetMethodName(id) << dex_file.GetMethodSignature(id).ToString() << "\n"; 4149 dex_data.Next(); 4150 } 4151} 4152 4153static std::string DumpClasses(const DexFile& dex_file1, const DexFile::ClassDef& dex_class_def1, 4154 const DexFile& dex_file2, const DexFile::ClassDef& dex_class_def2) { 4155 std::ostringstream os; 4156 DumpClass(os, dex_file1, dex_class_def1, " (Compile time)"); 4157 DumpClass(os, dex_file2, dex_class_def2, " (Runtime)"); 4158 return os.str(); 4159} 4160 4161 4162// Very simple structural check on whether the classes match. Only compares the number of 4163// methods and fields. 4164static bool SimpleStructuralCheck(const DexFile& dex_file1, const DexFile::ClassDef& dex_class_def1, 4165 const DexFile& dex_file2, const DexFile::ClassDef& dex_class_def2, 4166 std::string* error_msg) { 4167 ClassDataItemIterator dex_data1(dex_file1, dex_file1.GetClassData(dex_class_def1)); 4168 ClassDataItemIterator dex_data2(dex_file2, dex_file2.GetClassData(dex_class_def2)); 4169 4170 // Counters for current dex file. 4171 size_t dex_virtual_methods1, dex_direct_methods1, dex_static_fields1, dex_instance_fields1; 4172 CountMethodsAndFields(dex_data1, &dex_virtual_methods1, &dex_direct_methods1, &dex_static_fields1, 4173 &dex_instance_fields1); 4174 // Counters for compile-time dex file. 4175 size_t dex_virtual_methods2, dex_direct_methods2, dex_static_fields2, dex_instance_fields2; 4176 CountMethodsAndFields(dex_data2, &dex_virtual_methods2, &dex_direct_methods2, &dex_static_fields2, 4177 &dex_instance_fields2); 4178 4179 if (dex_virtual_methods1 != dex_virtual_methods2) { 4180 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 4181 *error_msg = StringPrintf("Virtual method count off: %zu vs %zu\n%s", dex_virtual_methods1, 4182 dex_virtual_methods2, class_dump.c_str()); 4183 return false; 4184 } 4185 if (dex_direct_methods1 != dex_direct_methods2) { 4186 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 4187 *error_msg = StringPrintf("Direct method count off: %zu vs %zu\n%s", dex_direct_methods1, 4188 dex_direct_methods2, class_dump.c_str()); 4189 return false; 4190 } 4191 if (dex_static_fields1 != dex_static_fields2) { 4192 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 4193 *error_msg = StringPrintf("Static field count off: %zu vs %zu\n%s", dex_static_fields1, 4194 dex_static_fields2, class_dump.c_str()); 4195 return false; 4196 } 4197 if (dex_instance_fields1 != dex_instance_fields2) { 4198 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 4199 *error_msg = StringPrintf("Instance field count off: %zu vs %zu\n%s", dex_instance_fields1, 4200 dex_instance_fields2, class_dump.c_str()); 4201 return false; 4202 } 4203 4204 return true; 4205} 4206 4207// Checks whether a the super-class changed from what we had at compile-time. This would 4208// invalidate quickening. 4209static bool CheckSuperClassChange(Handle<mirror::Class> klass, 4210 const DexFile& dex_file, 4211 const DexFile::ClassDef& class_def, 4212 mirror::Class* super_class) 4213 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4214 // Check for unexpected changes in the superclass. 4215 // Quick check 1) is the super_class class-loader the boot class loader? This always has 4216 // precedence. 4217 if (super_class->GetClassLoader() != nullptr && 4218 // Quick check 2) different dex cache? Breaks can only occur for different dex files, 4219 // which is implied by different dex cache. 4220 klass->GetDexCache() != super_class->GetDexCache()) { 4221 // Now comes the expensive part: things can be broken if (a) the klass' dex file has a 4222 // definition for the super-class, and (b) the files are in separate oat files. The oat files 4223 // are referenced from the dex file, so do (b) first. Only relevant if we have oat files. 4224 const OatDexFile* class_oat_dex_file = dex_file.GetOatDexFile(); 4225 const OatFile* class_oat_file = nullptr; 4226 if (class_oat_dex_file != nullptr) { 4227 class_oat_file = class_oat_dex_file->GetOatFile(); 4228 } 4229 4230 if (class_oat_file != nullptr) { 4231 const OatDexFile* loaded_super_oat_dex_file = super_class->GetDexFile().GetOatDexFile(); 4232 const OatFile* loaded_super_oat_file = nullptr; 4233 if (loaded_super_oat_dex_file != nullptr) { 4234 loaded_super_oat_file = loaded_super_oat_dex_file->GetOatFile(); 4235 } 4236 4237 if (loaded_super_oat_file != nullptr && class_oat_file != loaded_super_oat_file) { 4238 // Now check (a). 4239 const DexFile::ClassDef* super_class_def = dex_file.FindClassDef(class_def.superclass_idx_); 4240 if (super_class_def != nullptr) { 4241 // Uh-oh, we found something. Do our check. 4242 std::string error_msg; 4243 if (!SimpleStructuralCheck(dex_file, *super_class_def, 4244 super_class->GetDexFile(), *super_class->GetClassDef(), 4245 &error_msg)) { 4246 // Print a warning to the log. This exception might be caught, e.g., as common in test 4247 // drivers. When the class is later tried to be used, we re-throw a new instance, as we 4248 // only save the type of the exception. 4249 LOG(WARNING) << "Incompatible structural change detected: " << 4250 StringPrintf( 4251 "Structural change of %s is hazardous (%s at compile time, %s at runtime): %s", 4252 PrettyType(super_class_def->class_idx_, dex_file).c_str(), 4253 class_oat_file->GetLocation().c_str(), 4254 loaded_super_oat_file->GetLocation().c_str(), 4255 error_msg.c_str()); 4256 ThrowIncompatibleClassChangeError(klass.Get(), 4257 "Structural change of %s is hazardous (%s at compile time, %s at runtime): %s", 4258 PrettyType(super_class_def->class_idx_, dex_file).c_str(), 4259 class_oat_file->GetLocation().c_str(), 4260 loaded_super_oat_file->GetLocation().c_str(), 4261 error_msg.c_str()); 4262 return false; 4263 } 4264 } 4265 } 4266 } 4267 } 4268 return true; 4269} 4270 4271bool ClassLinker::LoadSuperAndInterfaces(Handle<mirror::Class> klass, const DexFile& dex_file) { 4272 CHECK_EQ(mirror::Class::kStatusIdx, klass->GetStatus()); 4273 const DexFile::ClassDef& class_def = dex_file.GetClassDef(klass->GetDexClassDefIndex()); 4274 uint16_t super_class_idx = class_def.superclass_idx_; 4275 if (super_class_idx != DexFile::kDexNoIndex16) { 4276 mirror::Class* super_class = ResolveType(dex_file, super_class_idx, klass.Get()); 4277 if (super_class == nullptr) { 4278 DCHECK(Thread::Current()->IsExceptionPending()); 4279 return false; 4280 } 4281 // Verify 4282 if (!klass->CanAccess(super_class)) { 4283 ThrowIllegalAccessError(klass.Get(), "Class %s extended by class %s is inaccessible", 4284 PrettyDescriptor(super_class).c_str(), 4285 PrettyDescriptor(klass.Get()).c_str()); 4286 return false; 4287 } 4288 CHECK(super_class->IsResolved()); 4289 klass->SetSuperClass(super_class); 4290 4291 if (!CheckSuperClassChange(klass, dex_file, class_def, super_class)) { 4292 DCHECK(Thread::Current()->IsExceptionPending()); 4293 return false; 4294 } 4295 } 4296 const DexFile::TypeList* interfaces = dex_file.GetInterfacesList(class_def); 4297 if (interfaces != nullptr) { 4298 for (size_t i = 0; i < interfaces->Size(); i++) { 4299 uint16_t idx = interfaces->GetTypeItem(i).type_idx_; 4300 mirror::Class* interface = ResolveType(dex_file, idx, klass.Get()); 4301 if (interface == nullptr) { 4302 DCHECK(Thread::Current()->IsExceptionPending()); 4303 return false; 4304 } 4305 // Verify 4306 if (!klass->CanAccess(interface)) { 4307 // TODO: the RI seemed to ignore this in my testing. 4308 ThrowIllegalAccessError(klass.Get(), "Interface %s implemented by class %s is inaccessible", 4309 PrettyDescriptor(interface).c_str(), 4310 PrettyDescriptor(klass.Get()).c_str()); 4311 return false; 4312 } 4313 } 4314 } 4315 // Mark the class as loaded. 4316 mirror::Class::SetStatus(klass, mirror::Class::kStatusLoaded, nullptr); 4317 return true; 4318} 4319 4320bool ClassLinker::LinkSuperClass(Handle<mirror::Class> klass) { 4321 CHECK(!klass->IsPrimitive()); 4322 mirror::Class* super = klass->GetSuperClass(); 4323 if (klass.Get() == GetClassRoot(kJavaLangObject)) { 4324 if (super != nullptr) { 4325 ThrowClassFormatError(klass.Get(), "java.lang.Object must not have a superclass"); 4326 return false; 4327 } 4328 return true; 4329 } 4330 if (super == nullptr) { 4331 ThrowLinkageError(klass.Get(), "No superclass defined for class %s", 4332 PrettyDescriptor(klass.Get()).c_str()); 4333 return false; 4334 } 4335 // Verify 4336 if (super->IsFinal() || super->IsInterface()) { 4337 ThrowIncompatibleClassChangeError(klass.Get(), "Superclass %s of %s is %s", 4338 PrettyDescriptor(super).c_str(), 4339 PrettyDescriptor(klass.Get()).c_str(), 4340 super->IsFinal() ? "declared final" : "an interface"); 4341 return false; 4342 } 4343 if (!klass->CanAccess(super)) { 4344 ThrowIllegalAccessError(klass.Get(), "Superclass %s is inaccessible to class %s", 4345 PrettyDescriptor(super).c_str(), 4346 PrettyDescriptor(klass.Get()).c_str()); 4347 return false; 4348 } 4349 4350 // Inherit kAccClassIsFinalizable from the superclass in case this 4351 // class doesn't override finalize. 4352 if (super->IsFinalizable()) { 4353 klass->SetFinalizable(); 4354 } 4355 4356 // Inherit reference flags (if any) from the superclass. 4357 int reference_flags = (super->GetAccessFlags() & kAccReferenceFlagsMask); 4358 if (reference_flags != 0) { 4359 klass->SetAccessFlags(klass->GetAccessFlags() | reference_flags); 4360 } 4361 // Disallow custom direct subclasses of java.lang.ref.Reference. 4362 if (init_done_ && super == GetClassRoot(kJavaLangRefReference)) { 4363 ThrowLinkageError(klass.Get(), 4364 "Class %s attempts to subclass java.lang.ref.Reference, which is not allowed", 4365 PrettyDescriptor(klass.Get()).c_str()); 4366 return false; 4367 } 4368 4369 if (kIsDebugBuild) { 4370 // Ensure super classes are fully resolved prior to resolving fields.. 4371 while (super != nullptr) { 4372 CHECK(super->IsResolved()); 4373 super = super->GetSuperClass(); 4374 } 4375 } 4376 return true; 4377} 4378 4379// Populate the class vtable and itable. Compute return type indices. 4380bool ClassLinker::LinkMethods(Thread* self, Handle<mirror::Class> klass, 4381 Handle<mirror::ObjectArray<mirror::Class>> interfaces, 4382 ArtMethod** out_imt) { 4383 self->AllowThreadSuspension(); 4384 if (klass->IsInterface()) { 4385 // No vtable. 4386 size_t count = klass->NumVirtualMethods(); 4387 if (!IsUint<16>(count)) { 4388 ThrowClassFormatError(klass.Get(), "Too many methods on interface: %zd", count); 4389 return false; 4390 } 4391 for (size_t i = 0; i < count; ++i) { 4392 klass->GetVirtualMethodDuringLinking(i, image_pointer_size_)->SetMethodIndex(i); 4393 } 4394 } else if (!LinkVirtualMethods(self, klass)) { // Link virtual methods first. 4395 return false; 4396 } 4397 return LinkInterfaceMethods(self, klass, interfaces, out_imt); // Link interface method last. 4398} 4399 4400// Comparator for name and signature of a method, used in finding overriding methods. Implementation 4401// avoids the use of handles, if it didn't then rather than compare dex files we could compare dex 4402// caches in the implementation below. 4403class MethodNameAndSignatureComparator FINAL : public ValueObject { 4404 public: 4405 explicit MethodNameAndSignatureComparator(ArtMethod* method) 4406 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) : 4407 dex_file_(method->GetDexFile()), mid_(&dex_file_->GetMethodId(method->GetDexMethodIndex())), 4408 name_(nullptr), name_len_(0) { 4409 DCHECK(!method->IsProxyMethod()) << PrettyMethod(method); 4410 } 4411 4412 const char* GetName() { 4413 if (name_ == nullptr) { 4414 name_ = dex_file_->StringDataAndUtf16LengthByIdx(mid_->name_idx_, &name_len_); 4415 } 4416 return name_; 4417 } 4418 4419 bool HasSameNameAndSignature(ArtMethod* other) 4420 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4421 DCHECK(!other->IsProxyMethod()) << PrettyMethod(other); 4422 const DexFile* other_dex_file = other->GetDexFile(); 4423 const DexFile::MethodId& other_mid = other_dex_file->GetMethodId(other->GetDexMethodIndex()); 4424 if (dex_file_ == other_dex_file) { 4425 return mid_->name_idx_ == other_mid.name_idx_ && mid_->proto_idx_ == other_mid.proto_idx_; 4426 } 4427 GetName(); // Only used to make sure its calculated. 4428 uint32_t other_name_len; 4429 const char* other_name = other_dex_file->StringDataAndUtf16LengthByIdx(other_mid.name_idx_, 4430 &other_name_len); 4431 if (name_len_ != other_name_len || strcmp(name_, other_name) != 0) { 4432 return false; 4433 } 4434 return dex_file_->GetMethodSignature(*mid_) == other_dex_file->GetMethodSignature(other_mid); 4435 } 4436 4437 private: 4438 // Dex file for the method to compare against. 4439 const DexFile* const dex_file_; 4440 // MethodId for the method to compare against. 4441 const DexFile::MethodId* const mid_; 4442 // Lazily computed name from the dex file's strings. 4443 const char* name_; 4444 // Lazily computed name length. 4445 uint32_t name_len_; 4446}; 4447 4448class LinkVirtualHashTable { 4449 public: 4450 LinkVirtualHashTable(Handle<mirror::Class> klass, size_t hash_size, uint32_t* hash_table, 4451 size_t image_pointer_size) 4452 : klass_(klass), hash_size_(hash_size), hash_table_(hash_table), 4453 image_pointer_size_(image_pointer_size) { 4454 std::fill(hash_table_, hash_table_ + hash_size_, invalid_index_); 4455 } 4456 void Add(uint32_t virtual_method_index) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4457 ArtMethod* local_method = klass_->GetVirtualMethodDuringLinking( 4458 virtual_method_index, image_pointer_size_); 4459 const char* name = local_method->GetInterfaceMethodIfProxy(image_pointer_size_)->GetName(); 4460 uint32_t hash = ComputeModifiedUtf8Hash(name); 4461 uint32_t index = hash % hash_size_; 4462 // Linear probe until we have an empty slot. 4463 while (hash_table_[index] != invalid_index_) { 4464 if (++index == hash_size_) { 4465 index = 0; 4466 } 4467 } 4468 hash_table_[index] = virtual_method_index; 4469 } 4470 uint32_t FindAndRemove(MethodNameAndSignatureComparator* comparator) 4471 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4472 const char* name = comparator->GetName(); 4473 uint32_t hash = ComputeModifiedUtf8Hash(name); 4474 size_t index = hash % hash_size_; 4475 while (true) { 4476 const uint32_t value = hash_table_[index]; 4477 // Since linear probe makes continuous blocks, hitting an invalid index means we are done 4478 // the block and can safely assume not found. 4479 if (value == invalid_index_) { 4480 break; 4481 } 4482 if (value != removed_index_) { // This signifies not already overriden. 4483 ArtMethod* virtual_method = 4484 klass_->GetVirtualMethodDuringLinking(value, image_pointer_size_); 4485 if (comparator->HasSameNameAndSignature( 4486 virtual_method->GetInterfaceMethodIfProxy(image_pointer_size_))) { 4487 hash_table_[index] = removed_index_; 4488 return value; 4489 } 4490 } 4491 if (++index == hash_size_) { 4492 index = 0; 4493 } 4494 } 4495 return GetNotFoundIndex(); 4496 } 4497 static uint32_t GetNotFoundIndex() { 4498 return invalid_index_; 4499 } 4500 4501 private: 4502 static const uint32_t invalid_index_; 4503 static const uint32_t removed_index_; 4504 4505 Handle<mirror::Class> klass_; 4506 const size_t hash_size_; 4507 uint32_t* const hash_table_; 4508 const size_t image_pointer_size_; 4509}; 4510 4511const uint32_t LinkVirtualHashTable::invalid_index_ = std::numeric_limits<uint32_t>::max(); 4512const uint32_t LinkVirtualHashTable::removed_index_ = std::numeric_limits<uint32_t>::max() - 1; 4513 4514bool ClassLinker::LinkVirtualMethods(Thread* self, Handle<mirror::Class> klass) { 4515 const size_t num_virtual_methods = klass->NumVirtualMethods(); 4516 if (klass->HasSuperClass()) { 4517 const size_t super_vtable_length = klass->GetSuperClass()->GetVTableLength(); 4518 const size_t max_count = num_virtual_methods + super_vtable_length; 4519 StackHandleScope<2> hs(self); 4520 Handle<mirror::Class> super_class(hs.NewHandle(klass->GetSuperClass())); 4521 MutableHandle<mirror::PointerArray> vtable; 4522 if (super_class->ShouldHaveEmbeddedImtAndVTable()) { 4523 vtable = hs.NewHandle(AllocPointerArray(self, max_count)); 4524 if (UNLIKELY(vtable.Get() == nullptr)) { 4525 self->AssertPendingOOMException(); 4526 return false; 4527 } 4528 for (size_t i = 0; i < super_vtable_length; i++) { 4529 vtable->SetElementPtrSize( 4530 i, super_class->GetEmbeddedVTableEntry(i, image_pointer_size_), image_pointer_size_); 4531 } 4532 if (num_virtual_methods == 0) { 4533 klass->SetVTable(vtable.Get()); 4534 return true; 4535 } 4536 } else { 4537 auto* super_vtable = super_class->GetVTable(); 4538 CHECK(super_vtable != nullptr) << PrettyClass(super_class.Get()); 4539 if (num_virtual_methods == 0) { 4540 klass->SetVTable(super_vtable); 4541 return true; 4542 } 4543 vtable = hs.NewHandle(down_cast<mirror::PointerArray*>( 4544 super_vtable->CopyOf(self, max_count))); 4545 if (UNLIKELY(vtable.Get() == nullptr)) { 4546 self->AssertPendingOOMException(); 4547 return false; 4548 } 4549 } 4550 // How the algorithm works: 4551 // 1. Populate hash table by adding num_virtual_methods from klass. The values in the hash 4552 // table are: invalid_index for unused slots, index super_vtable_length + i for a virtual 4553 // method which has not been matched to a vtable method, and j if the virtual method at the 4554 // index overrode the super virtual method at index j. 4555 // 2. Loop through super virtual methods, if they overwrite, update hash table to j 4556 // (j < super_vtable_length) to avoid redundant checks. (TODO maybe use this info for reducing 4557 // the need for the initial vtable which we later shrink back down). 4558 // 3. Add non overridden methods to the end of the vtable. 4559 static constexpr size_t kMaxStackHash = 250; 4560 const size_t hash_table_size = num_virtual_methods * 3; 4561 uint32_t* hash_table_ptr; 4562 std::unique_ptr<uint32_t[]> hash_heap_storage; 4563 if (hash_table_size <= kMaxStackHash) { 4564 hash_table_ptr = reinterpret_cast<uint32_t*>( 4565 alloca(hash_table_size * sizeof(*hash_table_ptr))); 4566 } else { 4567 hash_heap_storage.reset(new uint32_t[hash_table_size]); 4568 hash_table_ptr = hash_heap_storage.get(); 4569 } 4570 LinkVirtualHashTable hash_table(klass, hash_table_size, hash_table_ptr, image_pointer_size_); 4571 // Add virtual methods to the hash table. 4572 for (size_t i = 0; i < num_virtual_methods; ++i) { 4573 DCHECK(klass->GetVirtualMethodDuringLinking( 4574 i, image_pointer_size_)->GetDeclaringClass() != nullptr); 4575 hash_table.Add(i); 4576 } 4577 // Loop through each super vtable method and see if they are overriden by a method we added to 4578 // the hash table. 4579 for (size_t j = 0; j < super_vtable_length; ++j) { 4580 // Search the hash table to see if we are overidden by any method. 4581 ArtMethod* super_method = vtable->GetElementPtrSize<ArtMethod*>(j, image_pointer_size_); 4582 MethodNameAndSignatureComparator super_method_name_comparator( 4583 super_method->GetInterfaceMethodIfProxy(image_pointer_size_)); 4584 uint32_t hash_index = hash_table.FindAndRemove(&super_method_name_comparator); 4585 if (hash_index != hash_table.GetNotFoundIndex()) { 4586 ArtMethod* virtual_method = klass->GetVirtualMethodDuringLinking( 4587 hash_index, image_pointer_size_); 4588 if (klass->CanAccessMember(super_method->GetDeclaringClass(), 4589 super_method->GetAccessFlags())) { 4590 if (super_method->IsFinal()) { 4591 ThrowLinkageError(klass.Get(), "Method %s overrides final method in class %s", 4592 PrettyMethod(virtual_method).c_str(), 4593 super_method->GetDeclaringClassDescriptor()); 4594 return false; 4595 } 4596 vtable->SetElementPtrSize(j, virtual_method, image_pointer_size_); 4597 virtual_method->SetMethodIndex(j); 4598 } else { 4599 LOG(WARNING) << "Before Android 4.1, method " << PrettyMethod(virtual_method) 4600 << " would have incorrectly overridden the package-private method in " 4601 << PrettyDescriptor(super_method->GetDeclaringClassDescriptor()); 4602 } 4603 } 4604 } 4605 // Add the non overridden methods at the end. 4606 size_t actual_count = super_vtable_length; 4607 for (size_t i = 0; i < num_virtual_methods; ++i) { 4608 ArtMethod* local_method = klass->GetVirtualMethodDuringLinking(i, image_pointer_size_); 4609 size_t method_idx = local_method->GetMethodIndexDuringLinking(); 4610 if (method_idx < super_vtable_length && 4611 local_method == vtable->GetElementPtrSize<ArtMethod*>(method_idx, image_pointer_size_)) { 4612 continue; 4613 } 4614 vtable->SetElementPtrSize(actual_count, local_method, image_pointer_size_); 4615 local_method->SetMethodIndex(actual_count); 4616 ++actual_count; 4617 } 4618 if (!IsUint<16>(actual_count)) { 4619 ThrowClassFormatError(klass.Get(), "Too many methods defined on class: %zd", actual_count); 4620 return false; 4621 } 4622 // Shrink vtable if possible 4623 CHECK_LE(actual_count, max_count); 4624 if (actual_count < max_count) { 4625 vtable.Assign(down_cast<mirror::PointerArray*>(vtable->CopyOf(self, actual_count))); 4626 if (UNLIKELY(vtable.Get() == nullptr)) { 4627 self->AssertPendingOOMException(); 4628 return false; 4629 } 4630 } 4631 klass->SetVTable(vtable.Get()); 4632 } else { 4633 CHECK_EQ(klass.Get(), GetClassRoot(kJavaLangObject)); 4634 if (!IsUint<16>(num_virtual_methods)) { 4635 ThrowClassFormatError(klass.Get(), "Too many methods: %d", 4636 static_cast<int>(num_virtual_methods)); 4637 return false; 4638 } 4639 auto* vtable = AllocPointerArray(self, num_virtual_methods); 4640 if (UNLIKELY(vtable == nullptr)) { 4641 self->AssertPendingOOMException(); 4642 return false; 4643 } 4644 for (size_t i = 0; i < num_virtual_methods; ++i) { 4645 ArtMethod* virtual_method = klass->GetVirtualMethodDuringLinking(i, image_pointer_size_); 4646 vtable->SetElementPtrSize(i, virtual_method, image_pointer_size_); 4647 virtual_method->SetMethodIndex(i & 0xFFFF); 4648 } 4649 klass->SetVTable(vtable); 4650 } 4651 return true; 4652} 4653 4654bool ClassLinker::LinkInterfaceMethods(Thread* self, Handle<mirror::Class> klass, 4655 Handle<mirror::ObjectArray<mirror::Class>> interfaces, 4656 ArtMethod** out_imt) { 4657 StackHandleScope<3> hs(self); 4658 Runtime* const runtime = Runtime::Current(); 4659 const bool has_superclass = klass->HasSuperClass(); 4660 const size_t super_ifcount = has_superclass ? klass->GetSuperClass()->GetIfTableCount() : 0U; 4661 const bool have_interfaces = interfaces.Get() != nullptr; 4662 const size_t num_interfaces = 4663 have_interfaces ? interfaces->GetLength() : klass->NumDirectInterfaces(); 4664 const size_t method_size = ArtMethod::ObjectSize(image_pointer_size_); 4665 if (num_interfaces == 0) { 4666 if (super_ifcount == 0) { 4667 // Class implements no interfaces. 4668 DCHECK_EQ(klass->GetIfTableCount(), 0); 4669 DCHECK(klass->GetIfTable() == nullptr); 4670 return true; 4671 } 4672 // Class implements same interfaces as parent, are any of these not marker interfaces? 4673 bool has_non_marker_interface = false; 4674 mirror::IfTable* super_iftable = klass->GetSuperClass()->GetIfTable(); 4675 for (size_t i = 0; i < super_ifcount; ++i) { 4676 if (super_iftable->GetMethodArrayCount(i) > 0) { 4677 has_non_marker_interface = true; 4678 break; 4679 } 4680 } 4681 // Class just inherits marker interfaces from parent so recycle parent's iftable. 4682 if (!has_non_marker_interface) { 4683 klass->SetIfTable(super_iftable); 4684 return true; 4685 } 4686 } 4687 size_t ifcount = super_ifcount + num_interfaces; 4688 for (size_t i = 0; i < num_interfaces; i++) { 4689 mirror::Class* interface = have_interfaces ? 4690 interfaces->GetWithoutChecks(i) : mirror::Class::GetDirectInterface(self, klass, i); 4691 DCHECK(interface != nullptr); 4692 if (UNLIKELY(!interface->IsInterface())) { 4693 std::string temp; 4694 ThrowIncompatibleClassChangeError(klass.Get(), "Class %s implements non-interface class %s", 4695 PrettyDescriptor(klass.Get()).c_str(), 4696 PrettyDescriptor(interface->GetDescriptor(&temp)).c_str()); 4697 return false; 4698 } 4699 ifcount += interface->GetIfTableCount(); 4700 } 4701 MutableHandle<mirror::IfTable> iftable(hs.NewHandle(AllocIfTable(self, ifcount))); 4702 if (UNLIKELY(iftable.Get() == nullptr)) { 4703 self->AssertPendingOOMException(); 4704 return false; 4705 } 4706 if (super_ifcount != 0) { 4707 mirror::IfTable* super_iftable = klass->GetSuperClass()->GetIfTable(); 4708 for (size_t i = 0; i < super_ifcount; i++) { 4709 mirror::Class* super_interface = super_iftable->GetInterface(i); 4710 iftable->SetInterface(i, super_interface); 4711 } 4712 } 4713 self->AllowThreadSuspension(); 4714 // Flatten the interface inheritance hierarchy. 4715 size_t idx = super_ifcount; 4716 for (size_t i = 0; i < num_interfaces; i++) { 4717 mirror::Class* interface = have_interfaces ? interfaces->Get(i) : 4718 mirror::Class::GetDirectInterface(self, klass, i); 4719 // Check if interface is already in iftable 4720 bool duplicate = false; 4721 for (size_t j = 0; j < idx; j++) { 4722 mirror::Class* existing_interface = iftable->GetInterface(j); 4723 if (existing_interface == interface) { 4724 duplicate = true; 4725 break; 4726 } 4727 } 4728 if (!duplicate) { 4729 // Add this non-duplicate interface. 4730 iftable->SetInterface(idx++, interface); 4731 // Add this interface's non-duplicate super-interfaces. 4732 for (int32_t j = 0; j < interface->GetIfTableCount(); j++) { 4733 mirror::Class* super_interface = interface->GetIfTable()->GetInterface(j); 4734 bool super_duplicate = false; 4735 for (size_t k = 0; k < idx; k++) { 4736 mirror::Class* existing_interface = iftable->GetInterface(k); 4737 if (existing_interface == super_interface) { 4738 super_duplicate = true; 4739 break; 4740 } 4741 } 4742 if (!super_duplicate) { 4743 iftable->SetInterface(idx++, super_interface); 4744 } 4745 } 4746 } 4747 } 4748 self->AllowThreadSuspension(); 4749 // Shrink iftable in case duplicates were found 4750 if (idx < ifcount) { 4751 DCHECK_NE(num_interfaces, 0U); 4752 iftable.Assign(down_cast<mirror::IfTable*>( 4753 iftable->CopyOf(self, idx * mirror::IfTable::kMax))); 4754 if (UNLIKELY(iftable.Get() == nullptr)) { 4755 self->AssertPendingOOMException(); 4756 return false; 4757 } 4758 ifcount = idx; 4759 } else { 4760 DCHECK_EQ(idx, ifcount); 4761 } 4762 klass->SetIfTable(iftable.Get()); 4763 // If we're an interface, we don't need the vtable pointers, so we're done. 4764 if (klass->IsInterface()) { 4765 return true; 4766 } 4767 // These are allocated on the heap to begin, we then transfer to linear alloc when we re-create 4768 // the virtual methods array. 4769 // Need to use low 4GB arenas for compiler or else the pointers wont fit in 32 bit method array 4770 // during cross compilation. 4771 // Use the linear alloc pool since this one is in the low 4gb for the compiler. 4772 ArenaStack stack(runtime->GetLinearAlloc()->GetArenaPool()); 4773 ScopedArenaAllocator allocator(&stack); 4774 ScopedArenaVector<ArtMethod*> miranda_methods(allocator.Adapter()); 4775 4776 MutableHandle<mirror::PointerArray> vtable(hs.NewHandle(klass->GetVTableDuringLinking())); 4777 ArtMethod* const unimplemented_method = runtime->GetImtUnimplementedMethod(); 4778 ArtMethod* const conflict_method = runtime->GetImtConflictMethod(); 4779 // Copy the IMT from the super class if possible. 4780 bool extend_super_iftable = false; 4781 if (has_superclass) { 4782 mirror::Class* super_class = klass->GetSuperClass(); 4783 extend_super_iftable = true; 4784 if (super_class->ShouldHaveEmbeddedImtAndVTable()) { 4785 for (size_t i = 0; i < mirror::Class::kImtSize; ++i) { 4786 out_imt[i] = super_class->GetEmbeddedImTableEntry(i, image_pointer_size_); 4787 } 4788 } else { 4789 // No imt in the super class, need to reconstruct from the iftable. 4790 mirror::IfTable* if_table = super_class->GetIfTable(); 4791 const size_t length = super_class->GetIfTableCount(); 4792 for (size_t i = 0; i < length; ++i) { 4793 mirror::Class* interface = iftable->GetInterface(i); 4794 const size_t num_virtuals = interface->NumVirtualMethods(); 4795 const size_t method_array_count = if_table->GetMethodArrayCount(i); 4796 DCHECK_EQ(num_virtuals, method_array_count); 4797 if (method_array_count == 0) { 4798 continue; 4799 } 4800 auto* method_array = if_table->GetMethodArray(i); 4801 for (size_t j = 0; j < num_virtuals; ++j) { 4802 auto method = method_array->GetElementPtrSize<ArtMethod*>(j, image_pointer_size_); 4803 DCHECK(method != nullptr) << PrettyClass(super_class); 4804 if (method->IsMiranda()) { 4805 continue; 4806 } 4807 ArtMethod* interface_method = interface->GetVirtualMethod(j, image_pointer_size_); 4808 uint32_t imt_index = interface_method->GetDexMethodIndex() % mirror::Class::kImtSize; 4809 auto*& imt_ref = out_imt[imt_index]; 4810 if (imt_ref == unimplemented_method) { 4811 imt_ref = method; 4812 } else if (imt_ref != conflict_method) { 4813 imt_ref = conflict_method; 4814 } 4815 } 4816 } 4817 } 4818 } 4819 // Allocate method arrays before since we don't want miss visiting miranda method roots due to 4820 // thread suspension. 4821 for (size_t i = 0; i < ifcount; ++i) { 4822 size_t num_methods = iftable->GetInterface(i)->NumVirtualMethods(); 4823 if (num_methods > 0) { 4824 const bool is_super = i < super_ifcount; 4825 const bool super_interface = is_super && extend_super_iftable; 4826 mirror::PointerArray* method_array; 4827 if (super_interface) { 4828 mirror::IfTable* if_table = klass->GetSuperClass()->GetIfTable(); 4829 DCHECK(if_table != nullptr); 4830 DCHECK(if_table->GetMethodArray(i) != nullptr); 4831 // If we are working on a super interface, try extending the existing method array. 4832 method_array = down_cast<mirror::PointerArray*>(if_table->GetMethodArray(i)->Clone(self)); 4833 } else { 4834 method_array = AllocPointerArray(self, num_methods); 4835 } 4836 if (UNLIKELY(method_array == nullptr)) { 4837 self->AssertPendingOOMException(); 4838 return false; 4839 } 4840 iftable->SetMethodArray(i, method_array); 4841 } 4842 } 4843 4844 auto* old_cause = self->StartAssertNoThreadSuspension( 4845 "Copying ArtMethods for LinkInterfaceMethods"); 4846 for (size_t i = 0; i < ifcount; ++i) { 4847 size_t num_methods = iftable->GetInterface(i)->NumVirtualMethods(); 4848 if (num_methods > 0) { 4849 StackHandleScope<2> hs2(self); 4850 const bool is_super = i < super_ifcount; 4851 const bool super_interface = is_super && extend_super_iftable; 4852 auto method_array(hs2.NewHandle(iftable->GetMethodArray(i))); 4853 4854 ArtMethod* input_virtual_methods = nullptr; 4855 Handle<mirror::PointerArray> input_vtable_array = NullHandle<mirror::PointerArray>(); 4856 int32_t input_array_length = 0; 4857 if (super_interface) { 4858 // We are overwriting a super class interface, try to only virtual methods instead of the 4859 // whole vtable. 4860 input_virtual_methods = klass->GetVirtualMethodsPtr(); 4861 input_array_length = klass->NumVirtualMethods(); 4862 } else { 4863 // A new interface, we need the whole vtable in case a new interface method is implemented 4864 // in the whole superclass. 4865 input_vtable_array = vtable; 4866 input_array_length = input_vtable_array->GetLength(); 4867 } 4868 if (input_array_length == 0) { 4869 // If the added virtual methods is empty, do nothing. 4870 DCHECK(super_interface); 4871 continue; 4872 } 4873 for (size_t j = 0; j < num_methods; ++j) { 4874 auto* interface_method = iftable->GetInterface(i)->GetVirtualMethod( 4875 j, image_pointer_size_); 4876 MethodNameAndSignatureComparator interface_name_comparator( 4877 interface_method->GetInterfaceMethodIfProxy(image_pointer_size_)); 4878 int32_t k; 4879 // For each method listed in the interface's method list, find the 4880 // matching method in our class's method list. We want to favor the 4881 // subclass over the superclass, which just requires walking 4882 // back from the end of the vtable. (This only matters if the 4883 // superclass defines a private method and this class redefines 4884 // it -- otherwise it would use the same vtable slot. In .dex files 4885 // those don't end up in the virtual method table, so it shouldn't 4886 // matter which direction we go. We walk it backward anyway.) 4887 for (k = input_array_length - 1; k >= 0; --k) { 4888 ArtMethod* vtable_method = input_virtual_methods != nullptr ? 4889 reinterpret_cast<ArtMethod*>( 4890 reinterpret_cast<uintptr_t>(input_virtual_methods) + method_size * k) : 4891 input_vtable_array->GetElementPtrSize<ArtMethod*>(k, image_pointer_size_); 4892 ArtMethod* vtable_method_for_name_comparison = 4893 vtable_method->GetInterfaceMethodIfProxy(image_pointer_size_); 4894 if (interface_name_comparator.HasSameNameAndSignature( 4895 vtable_method_for_name_comparison)) { 4896 if (!vtable_method->IsAbstract() && !vtable_method->IsPublic()) { 4897 // Must do EndAssertNoThreadSuspension before throw since the throw can cause 4898 // allocations. 4899 self->EndAssertNoThreadSuspension(old_cause); 4900 ThrowIllegalAccessError(klass.Get(), 4901 "Method '%s' implementing interface method '%s' is not public", 4902 PrettyMethod(vtable_method).c_str(), PrettyMethod(interface_method).c_str()); 4903 return false; 4904 } 4905 method_array->SetElementPtrSize(j, vtable_method, image_pointer_size_); 4906 // Place method in imt if entry is empty, place conflict otherwise. 4907 uint32_t imt_index = interface_method->GetDexMethodIndex() % mirror::Class::kImtSize; 4908 auto** imt_ref = &out_imt[imt_index]; 4909 if (*imt_ref == unimplemented_method) { 4910 *imt_ref = vtable_method; 4911 } else if (*imt_ref != conflict_method) { 4912 // If we are not a conflict and we have the same signature and name as the imt entry, 4913 // it must be that we overwrote a superclass vtable entry. 4914 MethodNameAndSignatureComparator imt_comparator( 4915 (*imt_ref)->GetInterfaceMethodIfProxy(image_pointer_size_)); 4916 *imt_ref = imt_comparator.HasSameNameAndSignature(vtable_method_for_name_comparison) ? 4917 vtable_method : conflict_method; 4918 } 4919 break; 4920 } 4921 } 4922 if (k < 0 && !super_interface) { 4923 ArtMethod* miranda_method = nullptr; 4924 for (auto& mir_method : miranda_methods) { 4925 if (interface_name_comparator.HasSameNameAndSignature(mir_method)) { 4926 miranda_method = mir_method; 4927 break; 4928 } 4929 } 4930 if (miranda_method == nullptr) { 4931 size_t size = ArtMethod::ObjectSize(image_pointer_size_); 4932 miranda_method = reinterpret_cast<ArtMethod*>(allocator.Alloc(size)); 4933 CHECK(miranda_method != nullptr); 4934 // Point the interface table at a phantom slot. 4935 new(miranda_method) ArtMethod(*interface_method, image_pointer_size_); 4936 miranda_methods.push_back(miranda_method); 4937 } 4938 method_array->SetElementPtrSize(j, miranda_method, image_pointer_size_); 4939 } 4940 } 4941 } 4942 } 4943 if (!miranda_methods.empty()) { 4944 const size_t old_method_count = klass->NumVirtualMethods(); 4945 const size_t new_method_count = old_method_count + miranda_methods.size(); 4946 // Attempt to realloc to save RAM if possible. 4947 ArtMethod* old_virtuals = klass->GetVirtualMethodsPtr(); 4948 // The Realloced virtual methods aren't visiblef from the class roots, so there is no issue 4949 // where GCs could attempt to mark stale pointers due to memcpy. And since we overwrite the 4950 // realloced memory with out->CopyFrom, we are guaranteed to have objects in the to space since 4951 // CopyFrom has internal read barriers. 4952 auto* virtuals = reinterpret_cast<ArtMethod*>(runtime->GetLinearAlloc()->Realloc( 4953 self, old_virtuals, old_method_count * method_size, new_method_count * method_size)); 4954 if (UNLIKELY(virtuals == nullptr)) { 4955 self->AssertPendingOOMException(); 4956 return false; 4957 } 4958 ScopedArenaUnorderedMap<ArtMethod*, ArtMethod*> move_table(allocator.Adapter()); 4959 if (virtuals != old_virtuals) { 4960 // Maps from heap allocated miranda method to linear alloc miranda method. 4961 StrideIterator<ArtMethod> out(reinterpret_cast<uintptr_t>(virtuals), method_size); 4962 // Copy over the old methods + miranda methods. 4963 for (auto& m : klass->GetVirtualMethods(image_pointer_size_)) { 4964 move_table.emplace(&m, &*out); 4965 // The CopyFrom is only necessary to not miss read barriers since Realloc won't do read 4966 // barriers when it copies. 4967 out->CopyFrom(&m, image_pointer_size_); 4968 ++out; 4969 } 4970 } 4971 UpdateClassVirtualMethods(klass.Get(), virtuals, new_method_count); 4972 // Done copying methods, they are all reachable from the class now, so we can end the no thread 4973 // suspension assert. 4974 self->EndAssertNoThreadSuspension(old_cause); 4975 4976 size_t old_vtable_count = vtable->GetLength(); 4977 const size_t new_vtable_count = old_vtable_count + miranda_methods.size(); 4978 vtable.Assign(down_cast<mirror::PointerArray*>(vtable->CopyOf(self, new_vtable_count))); 4979 if (UNLIKELY(vtable.Get() == nullptr)) { 4980 self->AssertPendingOOMException(); 4981 return false; 4982 } 4983 StrideIterator<ArtMethod> out( 4984 reinterpret_cast<uintptr_t>(virtuals) + old_method_count * method_size, method_size); 4985 for (auto* mir_method : miranda_methods) { 4986 ArtMethod* out_method = &*out; 4987 out->CopyFrom(mir_method, image_pointer_size_); 4988 // Leave the declaring class alone as type indices are relative to it 4989 out_method->SetAccessFlags(out_method->GetAccessFlags() | kAccMiranda); 4990 out_method->SetMethodIndex(0xFFFF & old_vtable_count); 4991 vtable->SetElementPtrSize(old_vtable_count, out_method, image_pointer_size_); 4992 move_table.emplace(mir_method, out_method); 4993 ++out; 4994 ++old_vtable_count; 4995 } 4996 4997 // Update old vtable methods. 4998 for (size_t i = 0; i < old_vtable_count - miranda_methods.size(); ++i) { 4999 auto* m = vtable->GetElementPtrSize<ArtMethod*>(i, image_pointer_size_); 5000 DCHECK(m != nullptr) << PrettyClass(klass.Get()); 5001 auto it = move_table.find(m); 5002 if (it != move_table.end()) { 5003 auto* new_m = it->second; 5004 DCHECK(new_m != nullptr) << PrettyClass(klass.Get()); 5005 vtable->SetElementPtrSize(i, new_m, image_pointer_size_); 5006 } 5007 } 5008 klass->SetVTable(vtable.Get()); 5009 CHECK_EQ(old_vtable_count, new_vtable_count); 5010 // Go fix up all the stale miranda pointers. 5011 for (size_t i = 0; i < ifcount; ++i) { 5012 for (size_t j = 0, count = iftable->GetMethodArrayCount(i); j < count; ++j) { 5013 auto* method_array = iftable->GetMethodArray(i); 5014 auto* m = method_array->GetElementPtrSize<ArtMethod*>(j, image_pointer_size_); 5015 DCHECK(m != nullptr) << PrettyClass(klass.Get()); 5016 auto it = move_table.find(m); 5017 if (it != move_table.end()) { 5018 auto* new_m = it->second; 5019 DCHECK(new_m != nullptr) << PrettyClass(klass.Get()); 5020 method_array->SetElementPtrSize(j, new_m, image_pointer_size_); 5021 } 5022 } 5023 } 5024 // Fix up IMT in case it has any miranda methods in it. 5025 for (size_t i = 0; i < mirror::Class::kImtSize; ++i) { 5026 auto it = move_table.find(out_imt[i]); 5027 if (it != move_table.end()) { 5028 out_imt[i] = it->second; 5029 } 5030 } 5031 // Check that there are no stale methods are in the dex cache array. 5032 if (kIsDebugBuild) { 5033 auto* resolved_methods = klass->GetDexCache()->GetResolvedMethods(); 5034 for (size_t i = 0, count = resolved_methods->GetLength(); i < count; ++i) { 5035 auto* m = resolved_methods->GetElementPtrSize<ArtMethod*>(i, image_pointer_size_); 5036 CHECK(move_table.find(m) == move_table.end()) << PrettyMethod(m); 5037 } 5038 } 5039 // Put some random garbage in old virtuals to help find stale pointers. 5040 if (virtuals != old_virtuals) { 5041 memset(old_virtuals, 0xFEu, ArtMethod::ObjectSize(image_pointer_size_) * old_method_count); 5042 } 5043 } else { 5044 self->EndAssertNoThreadSuspension(old_cause); 5045 } 5046 if (kIsDebugBuild) { 5047 auto* check_vtable = klass->GetVTableDuringLinking(); 5048 for (int i = 0; i < check_vtable->GetLength(); ++i) { 5049 CHECK(check_vtable->GetElementPtrSize<ArtMethod*>(i, image_pointer_size_) != nullptr); 5050 } 5051 } 5052 return true; 5053} 5054 5055bool ClassLinker::LinkInstanceFields(Thread* self, Handle<mirror::Class> klass) { 5056 CHECK(klass.Get() != nullptr); 5057 return LinkFields(self, klass, false, nullptr); 5058} 5059 5060bool ClassLinker::LinkStaticFields(Thread* self, Handle<mirror::Class> klass, size_t* class_size) { 5061 CHECK(klass.Get() != nullptr); 5062 return LinkFields(self, klass, true, class_size); 5063} 5064 5065struct LinkFieldsComparator { 5066 explicit LinkFieldsComparator() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 5067 } 5068 // No thread safety analysis as will be called from STL. Checked lock held in constructor. 5069 bool operator()(ArtField* field1, ArtField* field2) 5070 NO_THREAD_SAFETY_ANALYSIS { 5071 // First come reference fields, then 64-bit, then 32-bit, and then 16-bit, then finally 8-bit. 5072 Primitive::Type type1 = field1->GetTypeAsPrimitiveType(); 5073 Primitive::Type type2 = field2->GetTypeAsPrimitiveType(); 5074 if (type1 != type2) { 5075 if (type1 == Primitive::kPrimNot) { 5076 // Reference always goes first. 5077 return true; 5078 } 5079 if (type2 == Primitive::kPrimNot) { 5080 // Reference always goes first. 5081 return false; 5082 } 5083 size_t size1 = Primitive::ComponentSize(type1); 5084 size_t size2 = Primitive::ComponentSize(type2); 5085 if (size1 != size2) { 5086 // Larger primitive types go first. 5087 return size1 > size2; 5088 } 5089 // Primitive types differ but sizes match. Arbitrarily order by primitive type. 5090 return type1 < type2; 5091 } 5092 // Same basic group? Then sort by dex field index. This is guaranteed to be sorted 5093 // by name and for equal names by type id index. 5094 // NOTE: This works also for proxies. Their static fields are assigned appropriate indexes. 5095 return field1->GetDexFieldIndex() < field2->GetDexFieldIndex(); 5096 } 5097}; 5098 5099bool ClassLinker::LinkFields(Thread* self, Handle<mirror::Class> klass, bool is_static, 5100 size_t* class_size) { 5101 self->AllowThreadSuspension(); 5102 const size_t num_fields = is_static ? klass->NumStaticFields() : klass->NumInstanceFields(); 5103 ArtField* const fields = is_static ? klass->GetSFields() : klass->GetIFields(); 5104 5105 // Initialize field_offset 5106 MemberOffset field_offset(0); 5107 if (is_static) { 5108 field_offset = klass->GetFirstReferenceStaticFieldOffsetDuringLinking(image_pointer_size_); 5109 } else { 5110 mirror::Class* super_class = klass->GetSuperClass(); 5111 if (super_class != nullptr) { 5112 CHECK(super_class->IsResolved()) 5113 << PrettyClass(klass.Get()) << " " << PrettyClass(super_class); 5114 field_offset = MemberOffset(super_class->GetObjectSize()); 5115 } 5116 } 5117 5118 CHECK_EQ(num_fields == 0, fields == nullptr) << PrettyClass(klass.Get()); 5119 5120 // we want a relatively stable order so that adding new fields 5121 // minimizes disruption of C++ version such as Class and Method. 5122 std::deque<ArtField*> grouped_and_sorted_fields; 5123 const char* old_no_suspend_cause = self->StartAssertNoThreadSuspension( 5124 "Naked ArtField references in deque"); 5125 for (size_t i = 0; i < num_fields; i++) { 5126 grouped_and_sorted_fields.push_back(&fields[i]); 5127 } 5128 std::sort(grouped_and_sorted_fields.begin(), grouped_and_sorted_fields.end(), 5129 LinkFieldsComparator()); 5130 5131 // References should be at the front. 5132 size_t current_field = 0; 5133 size_t num_reference_fields = 0; 5134 FieldGaps gaps; 5135 5136 for (; current_field < num_fields; current_field++) { 5137 ArtField* field = grouped_and_sorted_fields.front(); 5138 Primitive::Type type = field->GetTypeAsPrimitiveType(); 5139 bool isPrimitive = type != Primitive::kPrimNot; 5140 if (isPrimitive) { 5141 break; // past last reference, move on to the next phase 5142 } 5143 if (UNLIKELY(!IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>( 5144 field_offset.Uint32Value()))) { 5145 MemberOffset old_offset = field_offset; 5146 field_offset = MemberOffset(RoundUp(field_offset.Uint32Value(), 4)); 5147 AddFieldGap(old_offset.Uint32Value(), field_offset.Uint32Value(), &gaps); 5148 } 5149 DCHECK(IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>(field_offset.Uint32Value())); 5150 grouped_and_sorted_fields.pop_front(); 5151 num_reference_fields++; 5152 field->SetOffset(field_offset); 5153 field_offset = MemberOffset(field_offset.Uint32Value() + 5154 sizeof(mirror::HeapReference<mirror::Object>)); 5155 } 5156 // Gaps are stored as a max heap which means that we must shuffle from largest to smallest 5157 // otherwise we could end up with suboptimal gap fills. 5158 ShuffleForward<8>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 5159 ShuffleForward<4>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 5160 ShuffleForward<2>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 5161 ShuffleForward<1>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 5162 CHECK(grouped_and_sorted_fields.empty()) << "Missed " << grouped_and_sorted_fields.size() << 5163 " fields."; 5164 self->EndAssertNoThreadSuspension(old_no_suspend_cause); 5165 5166 // We lie to the GC about the java.lang.ref.Reference.referent field, so it doesn't scan it. 5167 if (!is_static && klass->DescriptorEquals("Ljava/lang/ref/Reference;")) { 5168 // We know there are no non-reference fields in the Reference classes, and we know 5169 // that 'referent' is alphabetically last, so this is easy... 5170 CHECK_EQ(num_reference_fields, num_fields) << PrettyClass(klass.Get()); 5171 CHECK_STREQ(fields[num_fields - 1].GetName(), "referent") << PrettyClass(klass.Get()); 5172 --num_reference_fields; 5173 } 5174 5175 size_t size = field_offset.Uint32Value(); 5176 // Update klass 5177 if (is_static) { 5178 klass->SetNumReferenceStaticFields(num_reference_fields); 5179 *class_size = size; 5180 } else { 5181 klass->SetNumReferenceInstanceFields(num_reference_fields); 5182 if (!klass->IsVariableSize()) { 5183 std::string temp; 5184 DCHECK_GE(size, sizeof(mirror::Object)) << klass->GetDescriptor(&temp); 5185 size_t previous_size = klass->GetObjectSize(); 5186 if (previous_size != 0) { 5187 // Make sure that we didn't originally have an incorrect size. 5188 CHECK_EQ(previous_size, size) << klass->GetDescriptor(&temp); 5189 } 5190 klass->SetObjectSize(size); 5191 } 5192 } 5193 5194 if (kIsDebugBuild) { 5195 // Make sure that the fields array is ordered by name but all reference 5196 // offsets are at the beginning as far as alignment allows. 5197 MemberOffset start_ref_offset = is_static 5198 ? klass->GetFirstReferenceStaticFieldOffsetDuringLinking(image_pointer_size_) 5199 : klass->GetFirstReferenceInstanceFieldOffset(); 5200 MemberOffset end_ref_offset(start_ref_offset.Uint32Value() + 5201 num_reference_fields * 5202 sizeof(mirror::HeapReference<mirror::Object>)); 5203 MemberOffset current_ref_offset = start_ref_offset; 5204 for (size_t i = 0; i < num_fields; i++) { 5205 ArtField* field = &fields[i]; 5206 VLOG(class_linker) << "LinkFields: " << (is_static ? "static" : "instance") 5207 << " class=" << PrettyClass(klass.Get()) << " field=" << PrettyField(field) << " offset=" 5208 << field->GetOffset(); 5209 if (i != 0) { 5210 ArtField* const prev_field = &fields[i - 1]; 5211 // NOTE: The field names can be the same. This is not possible in the Java language 5212 // but it's valid Java/dex bytecode and for example proguard can generate such bytecode. 5213 CHECK_LE(strcmp(prev_field->GetName(), field->GetName()), 0); 5214 } 5215 Primitive::Type type = field->GetTypeAsPrimitiveType(); 5216 bool is_primitive = type != Primitive::kPrimNot; 5217 if (klass->DescriptorEquals("Ljava/lang/ref/Reference;") && 5218 strcmp("referent", field->GetName()) == 0) { 5219 is_primitive = true; // We lied above, so we have to expect a lie here. 5220 } 5221 MemberOffset offset = field->GetOffsetDuringLinking(); 5222 if (is_primitive) { 5223 if (offset.Uint32Value() < end_ref_offset.Uint32Value()) { 5224 // Shuffled before references. 5225 size_t type_size = Primitive::ComponentSize(type); 5226 CHECK_LT(type_size, sizeof(mirror::HeapReference<mirror::Object>)); 5227 CHECK_LT(offset.Uint32Value(), start_ref_offset.Uint32Value()); 5228 CHECK_LE(offset.Uint32Value() + type_size, start_ref_offset.Uint32Value()); 5229 CHECK(!IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>(offset.Uint32Value())); 5230 } 5231 } else { 5232 CHECK_EQ(current_ref_offset.Uint32Value(), offset.Uint32Value()); 5233 current_ref_offset = MemberOffset(current_ref_offset.Uint32Value() + 5234 sizeof(mirror::HeapReference<mirror::Object>)); 5235 } 5236 } 5237 CHECK_EQ(current_ref_offset.Uint32Value(), end_ref_offset.Uint32Value()); 5238 } 5239 return true; 5240} 5241 5242// Set the bitmap of reference instance field offsets. 5243void ClassLinker::CreateReferenceInstanceOffsets(Handle<mirror::Class> klass) { 5244 uint32_t reference_offsets = 0; 5245 mirror::Class* super_class = klass->GetSuperClass(); 5246 // Leave the reference offsets as 0 for mirror::Object (the class field is handled specially). 5247 if (super_class != nullptr) { 5248 reference_offsets = super_class->GetReferenceInstanceOffsets(); 5249 // Compute reference offsets unless our superclass overflowed. 5250 if (reference_offsets != mirror::Class::kClassWalkSuper) { 5251 size_t num_reference_fields = klass->NumReferenceInstanceFieldsDuringLinking(); 5252 if (num_reference_fields != 0u) { 5253 // All of the fields that contain object references are guaranteed be grouped in memory 5254 // starting at an appropriately aligned address after super class object data. 5255 uint32_t start_offset = RoundUp(super_class->GetObjectSize(), 5256 sizeof(mirror::HeapReference<mirror::Object>)); 5257 uint32_t start_bit = (start_offset - mirror::kObjectHeaderSize) / 5258 sizeof(mirror::HeapReference<mirror::Object>); 5259 if (start_bit + num_reference_fields > 32) { 5260 reference_offsets = mirror::Class::kClassWalkSuper; 5261 } else { 5262 reference_offsets |= (0xffffffffu << start_bit) & 5263 (0xffffffffu >> (32 - (start_bit + num_reference_fields))); 5264 } 5265 } 5266 } 5267 } 5268 klass->SetReferenceInstanceOffsets(reference_offsets); 5269} 5270 5271mirror::String* ClassLinker::ResolveString(const DexFile& dex_file, uint32_t string_idx, 5272 Handle<mirror::DexCache> dex_cache) { 5273 DCHECK(dex_cache.Get() != nullptr); 5274 mirror::String* resolved = dex_cache->GetResolvedString(string_idx); 5275 if (resolved != nullptr) { 5276 return resolved; 5277 } 5278 uint32_t utf16_length; 5279 const char* utf8_data = dex_file.StringDataAndUtf16LengthByIdx(string_idx, &utf16_length); 5280 mirror::String* string = intern_table_->InternStrong(utf16_length, utf8_data); 5281 dex_cache->SetResolvedString(string_idx, string); 5282 return string; 5283} 5284 5285mirror::Class* ClassLinker::ResolveType(const DexFile& dex_file, uint16_t type_idx, 5286 mirror::Class* referrer) { 5287 StackHandleScope<2> hs(Thread::Current()); 5288 Handle<mirror::DexCache> dex_cache(hs.NewHandle(referrer->GetDexCache())); 5289 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(referrer->GetClassLoader())); 5290 return ResolveType(dex_file, type_idx, dex_cache, class_loader); 5291} 5292 5293mirror::Class* ClassLinker::ResolveType(const DexFile& dex_file, uint16_t type_idx, 5294 Handle<mirror::DexCache> dex_cache, 5295 Handle<mirror::ClassLoader> class_loader) { 5296 DCHECK(dex_cache.Get() != nullptr); 5297 mirror::Class* resolved = dex_cache->GetResolvedType(type_idx); 5298 if (resolved == nullptr) { 5299 Thread* self = Thread::Current(); 5300 const char* descriptor = dex_file.StringByTypeIdx(type_idx); 5301 resolved = FindClass(self, descriptor, class_loader); 5302 if (resolved != nullptr) { 5303 // TODO: we used to throw here if resolved's class loader was not the 5304 // boot class loader. This was to permit different classes with the 5305 // same name to be loaded simultaneously by different loaders 5306 dex_cache->SetResolvedType(type_idx, resolved); 5307 } else { 5308 CHECK(self->IsExceptionPending()) 5309 << "Expected pending exception for failed resolution of: " << descriptor; 5310 // Convert a ClassNotFoundException to a NoClassDefFoundError. 5311 StackHandleScope<1> hs(self); 5312 Handle<mirror::Throwable> cause(hs.NewHandle(self->GetException())); 5313 if (cause->InstanceOf(GetClassRoot(kJavaLangClassNotFoundException))) { 5314 DCHECK(resolved == nullptr); // No Handle needed to preserve resolved. 5315 self->ClearException(); 5316 ThrowNoClassDefFoundError("Failed resolution of: %s", descriptor); 5317 self->GetException()->SetCause(cause.Get()); 5318 } 5319 } 5320 } 5321 DCHECK((resolved == nullptr) || resolved->IsResolved() || resolved->IsErroneous()) 5322 << PrettyDescriptor(resolved) << " " << resolved->GetStatus(); 5323 return resolved; 5324} 5325 5326ArtMethod* ClassLinker::ResolveMethod(const DexFile& dex_file, uint32_t method_idx, 5327 Handle<mirror::DexCache> dex_cache, 5328 Handle<mirror::ClassLoader> class_loader, 5329 ArtMethod* referrer, InvokeType type) { 5330 DCHECK(dex_cache.Get() != nullptr); 5331 // Check for hit in the dex cache. 5332 ArtMethod* resolved = dex_cache->GetResolvedMethod(method_idx, image_pointer_size_); 5333 if (resolved != nullptr && !resolved->IsRuntimeMethod()) { 5334 DCHECK(resolved->GetDeclaringClassUnchecked() != nullptr) << resolved->GetDexMethodIndex(); 5335 return resolved; 5336 } 5337 // Fail, get the declaring class. 5338 const DexFile::MethodId& method_id = dex_file.GetMethodId(method_idx); 5339 mirror::Class* klass = ResolveType(dex_file, method_id.class_idx_, dex_cache, class_loader); 5340 if (klass == nullptr) { 5341 DCHECK(Thread::Current()->IsExceptionPending()); 5342 return nullptr; 5343 } 5344 // Scan using method_idx, this saves string compares but will only hit for matching dex 5345 // caches/files. 5346 switch (type) { 5347 case kDirect: // Fall-through. 5348 case kStatic: 5349 resolved = klass->FindDirectMethod(dex_cache.Get(), method_idx, image_pointer_size_); 5350 DCHECK(resolved == nullptr || resolved->GetDeclaringClassUnchecked() != nullptr); 5351 break; 5352 case kInterface: 5353 resolved = klass->FindInterfaceMethod(dex_cache.Get(), method_idx, image_pointer_size_); 5354 DCHECK(resolved == nullptr || resolved->GetDeclaringClass()->IsInterface()); 5355 break; 5356 case kSuper: // Fall-through. 5357 case kVirtual: 5358 resolved = klass->FindVirtualMethod(dex_cache.Get(), method_idx, image_pointer_size_); 5359 break; 5360 default: 5361 LOG(FATAL) << "Unreachable - invocation type: " << type; 5362 UNREACHABLE(); 5363 } 5364 if (resolved == nullptr) { 5365 // Search by name, which works across dex files. 5366 const char* name = dex_file.StringDataByIdx(method_id.name_idx_); 5367 const Signature signature = dex_file.GetMethodSignature(method_id); 5368 switch (type) { 5369 case kDirect: // Fall-through. 5370 case kStatic: 5371 resolved = klass->FindDirectMethod(name, signature, image_pointer_size_); 5372 DCHECK(resolved == nullptr || resolved->GetDeclaringClassUnchecked() != nullptr); 5373 break; 5374 case kInterface: 5375 resolved = klass->FindInterfaceMethod(name, signature, image_pointer_size_); 5376 DCHECK(resolved == nullptr || resolved->GetDeclaringClass()->IsInterface()); 5377 break; 5378 case kSuper: // Fall-through. 5379 case kVirtual: 5380 resolved = klass->FindVirtualMethod(name, signature, image_pointer_size_); 5381 break; 5382 } 5383 } 5384 // If we found a method, check for incompatible class changes. 5385 if (LIKELY(resolved != nullptr && !resolved->CheckIncompatibleClassChange(type))) { 5386 // Be a good citizen and update the dex cache to speed subsequent calls. 5387 dex_cache->SetResolvedMethod(method_idx, resolved, image_pointer_size_); 5388 return resolved; 5389 } else { 5390 // If we had a method, it's an incompatible-class-change error. 5391 if (resolved != nullptr) { 5392 ThrowIncompatibleClassChangeError(type, resolved->GetInvokeType(), resolved, referrer); 5393 } else { 5394 // We failed to find the method which means either an access error, an incompatible class 5395 // change, or no such method. First try to find the method among direct and virtual methods. 5396 const char* name = dex_file.StringDataByIdx(method_id.name_idx_); 5397 const Signature signature = dex_file.GetMethodSignature(method_id); 5398 switch (type) { 5399 case kDirect: 5400 case kStatic: 5401 resolved = klass->FindVirtualMethod(name, signature, image_pointer_size_); 5402 // Note: kDirect and kStatic are also mutually exclusive, but in that case we would 5403 // have had a resolved method before, which triggers the "true" branch above. 5404 break; 5405 case kInterface: 5406 case kVirtual: 5407 case kSuper: 5408 resolved = klass->FindDirectMethod(name, signature, image_pointer_size_); 5409 break; 5410 } 5411 5412 // If we found something, check that it can be accessed by the referrer. 5413 bool exception_generated = false; 5414 if (resolved != nullptr && referrer != nullptr) { 5415 mirror::Class* methods_class = resolved->GetDeclaringClass(); 5416 mirror::Class* referring_class = referrer->GetDeclaringClass(); 5417 if (!referring_class->CanAccess(methods_class)) { 5418 ThrowIllegalAccessErrorClassForMethodDispatch(referring_class, methods_class, resolved, 5419 type); 5420 exception_generated = true; 5421 } else if (!referring_class->CanAccessMember(methods_class, resolved->GetAccessFlags())) { 5422 ThrowIllegalAccessErrorMethod(referring_class, resolved); 5423 exception_generated = true; 5424 } 5425 } 5426 if (!exception_generated) { 5427 // Otherwise, throw an IncompatibleClassChangeError if we found something, and check 5428 // interface methods and throw if we find the method there. If we find nothing, throw a 5429 // NoSuchMethodError. 5430 switch (type) { 5431 case kDirect: 5432 case kStatic: 5433 if (resolved != nullptr) { 5434 ThrowIncompatibleClassChangeError(type, kVirtual, resolved, referrer); 5435 } else { 5436 resolved = klass->FindInterfaceMethod(name, signature, image_pointer_size_); 5437 if (resolved != nullptr) { 5438 ThrowIncompatibleClassChangeError(type, kInterface, resolved, referrer); 5439 } else { 5440 ThrowNoSuchMethodError(type, klass, name, signature); 5441 } 5442 } 5443 break; 5444 case kInterface: 5445 if (resolved != nullptr) { 5446 ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer); 5447 } else { 5448 resolved = klass->FindVirtualMethod(name, signature, image_pointer_size_); 5449 if (resolved != nullptr) { 5450 ThrowIncompatibleClassChangeError(type, kVirtual, resolved, referrer); 5451 } else { 5452 ThrowNoSuchMethodError(type, klass, name, signature); 5453 } 5454 } 5455 break; 5456 case kSuper: 5457 if (resolved != nullptr) { 5458 ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer); 5459 } else { 5460 ThrowNoSuchMethodError(type, klass, name, signature); 5461 } 5462 break; 5463 case kVirtual: 5464 if (resolved != nullptr) { 5465 ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer); 5466 } else { 5467 resolved = klass->FindInterfaceMethod(name, signature, image_pointer_size_); 5468 if (resolved != nullptr) { 5469 ThrowIncompatibleClassChangeError(type, kInterface, resolved, referrer); 5470 } else { 5471 ThrowNoSuchMethodError(type, klass, name, signature); 5472 } 5473 } 5474 break; 5475 } 5476 } 5477 } 5478 Thread::Current()->AssertPendingException(); 5479 return nullptr; 5480 } 5481} 5482 5483ArtField* ClassLinker::ResolveField(const DexFile& dex_file, uint32_t field_idx, 5484 Handle<mirror::DexCache> dex_cache, 5485 Handle<mirror::ClassLoader> class_loader, bool is_static) { 5486 DCHECK(dex_cache.Get() != nullptr); 5487 ArtField* resolved = dex_cache->GetResolvedField(field_idx, image_pointer_size_); 5488 if (resolved != nullptr) { 5489 return resolved; 5490 } 5491 const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx); 5492 Thread* const self = Thread::Current(); 5493 StackHandleScope<1> hs(self); 5494 Handle<mirror::Class> klass( 5495 hs.NewHandle(ResolveType(dex_file, field_id.class_idx_, dex_cache, class_loader))); 5496 if (klass.Get() == nullptr) { 5497 DCHECK(Thread::Current()->IsExceptionPending()); 5498 return nullptr; 5499 } 5500 5501 if (is_static) { 5502 resolved = mirror::Class::FindStaticField(self, klass, dex_cache.Get(), field_idx); 5503 } else { 5504 resolved = klass->FindInstanceField(dex_cache.Get(), field_idx); 5505 } 5506 5507 if (resolved == nullptr) { 5508 const char* name = dex_file.GetFieldName(field_id); 5509 const char* type = dex_file.GetFieldTypeDescriptor(field_id); 5510 if (is_static) { 5511 resolved = mirror::Class::FindStaticField(self, klass, name, type); 5512 } else { 5513 resolved = klass->FindInstanceField(name, type); 5514 } 5515 if (resolved == nullptr) { 5516 ThrowNoSuchFieldError(is_static ? "static " : "instance ", klass.Get(), type, name); 5517 return nullptr; 5518 } 5519 } 5520 dex_cache->SetResolvedField(field_idx, resolved, image_pointer_size_); 5521 return resolved; 5522} 5523 5524ArtField* ClassLinker::ResolveFieldJLS(const DexFile& dex_file, uint32_t field_idx, 5525 Handle<mirror::DexCache> dex_cache, 5526 Handle<mirror::ClassLoader> class_loader) { 5527 DCHECK(dex_cache.Get() != nullptr); 5528 ArtField* resolved = dex_cache->GetResolvedField(field_idx, image_pointer_size_); 5529 if (resolved != nullptr) { 5530 return resolved; 5531 } 5532 const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx); 5533 Thread* self = Thread::Current(); 5534 StackHandleScope<1> hs(self); 5535 Handle<mirror::Class> klass( 5536 hs.NewHandle(ResolveType(dex_file, field_id.class_idx_, dex_cache, class_loader))); 5537 if (klass.Get() == nullptr) { 5538 DCHECK(Thread::Current()->IsExceptionPending()); 5539 return nullptr; 5540 } 5541 5542 StringPiece name(dex_file.StringDataByIdx(field_id.name_idx_)); 5543 StringPiece type(dex_file.StringDataByIdx( 5544 dex_file.GetTypeId(field_id.type_idx_).descriptor_idx_)); 5545 resolved = mirror::Class::FindField(self, klass, name, type); 5546 if (resolved != nullptr) { 5547 dex_cache->SetResolvedField(field_idx, resolved, image_pointer_size_); 5548 } else { 5549 ThrowNoSuchFieldError("", klass.Get(), type, name); 5550 } 5551 return resolved; 5552} 5553 5554const char* ClassLinker::MethodShorty(uint32_t method_idx, ArtMethod* referrer, 5555 uint32_t* length) { 5556 mirror::Class* declaring_class = referrer->GetDeclaringClass(); 5557 mirror::DexCache* dex_cache = declaring_class->GetDexCache(); 5558 const DexFile& dex_file = *dex_cache->GetDexFile(); 5559 const DexFile::MethodId& method_id = dex_file.GetMethodId(method_idx); 5560 return dex_file.GetMethodShorty(method_id, length); 5561} 5562 5563void ClassLinker::DumpAllClasses(int flags) { 5564 if (dex_cache_image_class_lookup_required_) { 5565 MoveImageClassesToClassTable(); 5566 } 5567 // TODO: at the time this was written, it wasn't safe to call PrettyField with the ClassLinker 5568 // lock held, because it might need to resolve a field's type, which would try to take the lock. 5569 std::vector<mirror::Class*> all_classes; 5570 { 5571 ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 5572 for (GcRoot<mirror::Class>& it : class_table_) { 5573 all_classes.push_back(it.Read()); 5574 } 5575 } 5576 5577 for (size_t i = 0; i < all_classes.size(); ++i) { 5578 all_classes[i]->DumpClass(std::cerr, flags); 5579 } 5580} 5581 5582static OatFile::OatMethod CreateOatMethod(const void* code) { 5583 CHECK(code != nullptr); 5584 const uint8_t* base = reinterpret_cast<const uint8_t*>(code); // Base of data points at code. 5585 base -= sizeof(void*); // Move backward so that code_offset != 0. 5586 const uint32_t code_offset = sizeof(void*); 5587 return OatFile::OatMethod(base, code_offset); 5588} 5589 5590bool ClassLinker::IsQuickResolutionStub(const void* entry_point) const { 5591 return (entry_point == GetQuickResolutionStub()) || 5592 (quick_resolution_trampoline_ == entry_point); 5593} 5594 5595bool ClassLinker::IsQuickToInterpreterBridge(const void* entry_point) const { 5596 return (entry_point == GetQuickToInterpreterBridge()) || 5597 (quick_to_interpreter_bridge_trampoline_ == entry_point); 5598} 5599 5600bool ClassLinker::IsQuickGenericJniStub(const void* entry_point) const { 5601 return (entry_point == GetQuickGenericJniStub()) || 5602 (quick_generic_jni_trampoline_ == entry_point); 5603} 5604 5605const void* ClassLinker::GetRuntimeQuickGenericJniStub() const { 5606 return GetQuickGenericJniStub(); 5607} 5608 5609void ClassLinker::SetEntryPointsToCompiledCode(ArtMethod* method, 5610 const void* method_code) const { 5611 OatFile::OatMethod oat_method = CreateOatMethod(method_code); 5612 oat_method.LinkMethod(method); 5613 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 5614} 5615 5616void ClassLinker::SetEntryPointsToInterpreter(ArtMethod* method) const { 5617 if (!method->IsNative()) { 5618 method->SetEntryPointFromInterpreter(artInterpreterToInterpreterBridge); 5619 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge()); 5620 } else { 5621 const void* quick_method_code = GetQuickGenericJniStub(); 5622 OatFile::OatMethod oat_method = CreateOatMethod(quick_method_code); 5623 oat_method.LinkMethod(method); 5624 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 5625 } 5626} 5627 5628void ClassLinker::DumpForSigQuit(std::ostream& os) { 5629 Thread* self = Thread::Current(); 5630 if (dex_cache_image_class_lookup_required_) { 5631 ScopedObjectAccess soa(self); 5632 MoveImageClassesToClassTable(); 5633 } 5634 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 5635 os << "Zygote loaded classes=" << pre_zygote_class_table_.Size() << " post zygote classes=" 5636 << class_table_.Size() << "\n"; 5637} 5638 5639size_t ClassLinker::NumLoadedClasses() { 5640 if (dex_cache_image_class_lookup_required_) { 5641 MoveImageClassesToClassTable(); 5642 } 5643 ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 5644 // Only return non zygote classes since these are the ones which apps which care about. 5645 return class_table_.Size(); 5646} 5647 5648pid_t ClassLinker::GetClassesLockOwner() { 5649 return Locks::classlinker_classes_lock_->GetExclusiveOwnerTid(); 5650} 5651 5652pid_t ClassLinker::GetDexLockOwner() { 5653 return dex_lock_.GetExclusiveOwnerTid(); 5654} 5655 5656void ClassLinker::SetClassRoot(ClassRoot class_root, mirror::Class* klass) { 5657 DCHECK(!init_done_); 5658 5659 DCHECK(klass != nullptr); 5660 DCHECK(klass->GetClassLoader() == nullptr); 5661 5662 mirror::ObjectArray<mirror::Class>* class_roots = class_roots_.Read(); 5663 DCHECK(class_roots != nullptr); 5664 DCHECK(class_roots->Get(class_root) == nullptr); 5665 class_roots->Set<false>(class_root, klass); 5666} 5667 5668const char* ClassLinker::GetClassRootDescriptor(ClassRoot class_root) { 5669 static const char* class_roots_descriptors[] = { 5670 "Ljava/lang/Class;", 5671 "Ljava/lang/Object;", 5672 "[Ljava/lang/Class;", 5673 "[Ljava/lang/Object;", 5674 "Ljava/lang/String;", 5675 "Ljava/lang/DexCache;", 5676 "Ljava/lang/ref/Reference;", 5677 "Ljava/lang/reflect/Constructor;", 5678 "Ljava/lang/reflect/Field;", 5679 "Ljava/lang/reflect/Method;", 5680 "Ljava/lang/reflect/Proxy;", 5681 "[Ljava/lang/String;", 5682 "[Ljava/lang/reflect/Constructor;", 5683 "[Ljava/lang/reflect/Field;", 5684 "[Ljava/lang/reflect/Method;", 5685 "Ljava/lang/ClassLoader;", 5686 "Ljava/lang/Throwable;", 5687 "Ljava/lang/ClassNotFoundException;", 5688 "Ljava/lang/StackTraceElement;", 5689 "Z", 5690 "B", 5691 "C", 5692 "D", 5693 "F", 5694 "I", 5695 "J", 5696 "S", 5697 "V", 5698 "[Z", 5699 "[B", 5700 "[C", 5701 "[D", 5702 "[F", 5703 "[I", 5704 "[J", 5705 "[S", 5706 "[Ljava/lang/StackTraceElement;", 5707 }; 5708 static_assert(arraysize(class_roots_descriptors) == size_t(kClassRootsMax), 5709 "Mismatch between class descriptors and class-root enum"); 5710 5711 const char* descriptor = class_roots_descriptors[class_root]; 5712 CHECK(descriptor != nullptr); 5713 return descriptor; 5714} 5715 5716std::size_t ClassLinker::ClassDescriptorHashEquals::operator()(const GcRoot<mirror::Class>& root) 5717 const { 5718 std::string temp; 5719 return ComputeModifiedUtf8Hash(root.Read()->GetDescriptor(&temp)); 5720} 5721 5722bool ClassLinker::ClassDescriptorHashEquals::operator()(const GcRoot<mirror::Class>& a, 5723 const GcRoot<mirror::Class>& b) const { 5724 if (a.Read()->GetClassLoader() != b.Read()->GetClassLoader()) { 5725 return false; 5726 } 5727 std::string temp; 5728 return a.Read()->DescriptorEquals(b.Read()->GetDescriptor(&temp)); 5729} 5730 5731std::size_t ClassLinker::ClassDescriptorHashEquals::operator()( 5732 const std::pair<const char*, mirror::ClassLoader*>& element) const { 5733 return ComputeModifiedUtf8Hash(element.first); 5734} 5735 5736bool ClassLinker::ClassDescriptorHashEquals::operator()( 5737 const GcRoot<mirror::Class>& a, const std::pair<const char*, mirror::ClassLoader*>& b) const { 5738 if (a.Read()->GetClassLoader() != b.second) { 5739 return false; 5740 } 5741 return a.Read()->DescriptorEquals(b.first); 5742} 5743 5744bool ClassLinker::ClassDescriptorHashEquals::operator()(const GcRoot<mirror::Class>& a, 5745 const char* descriptor) const { 5746 return a.Read()->DescriptorEquals(descriptor); 5747} 5748 5749std::size_t ClassLinker::ClassDescriptorHashEquals::operator()(const char* descriptor) const { 5750 return ComputeModifiedUtf8Hash(descriptor); 5751} 5752 5753bool ClassLinker::MayBeCalledWithDirectCodePointer(ArtMethod* m) { 5754 if (Runtime::Current()->UseJit()) { 5755 // JIT can have direct code pointers from any method to any other method. 5756 return true; 5757 } 5758 // Non-image methods don't use direct code pointer. 5759 if (!m->GetDeclaringClass()->IsBootStrapClassLoaded()) { 5760 return false; 5761 } 5762 if (m->IsPrivate()) { 5763 // The method can only be called inside its own oat file. Therefore it won't be called using 5764 // its direct code if the oat file has been compiled in PIC mode. 5765 const DexFile& dex_file = m->GetDeclaringClass()->GetDexFile(); 5766 const OatFile::OatDexFile* oat_dex_file = dex_file.GetOatDexFile(); 5767 if (oat_dex_file == nullptr) { 5768 // No oat file: the method has not been compiled. 5769 return false; 5770 } 5771 const OatFile* oat_file = oat_dex_file->GetOatFile(); 5772 return oat_file != nullptr && !oat_file->IsPic(); 5773 } else { 5774 // The method can be called outside its own oat file. Therefore it won't be called using its 5775 // direct code pointer only if all loaded oat files have been compiled in PIC mode. 5776 ReaderMutexLock mu(Thread::Current(), dex_lock_); 5777 for (const OatFile* oat_file : oat_files_) { 5778 if (!oat_file->IsPic()) { 5779 return true; 5780 } 5781 } 5782 return false; 5783 } 5784} 5785 5786jobject ClassLinker::CreatePathClassLoader(Thread* self, std::vector<const DexFile*>& dex_files) { 5787 // SOAAlreadyRunnable is protected, and we need something to add a global reference. 5788 // We could move the jobject to the callers, but all call-sites do this... 5789 ScopedObjectAccessUnchecked soa(self); 5790 5791 // Register the dex files. 5792 for (const DexFile* dex_file : dex_files) { 5793 RegisterDexFile(*dex_file); 5794 } 5795 5796 // For now, create a libcore-level DexFile for each ART DexFile. This "explodes" multidex. 5797 StackHandleScope<10> hs(self); 5798 5799 ArtField* dex_elements_field = 5800 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList_dexElements); 5801 5802 mirror::Class* dex_elements_class = dex_elements_field->GetType<true>(); 5803 DCHECK(dex_elements_class != nullptr); 5804 DCHECK(dex_elements_class->IsArrayClass()); 5805 Handle<mirror::ObjectArray<mirror::Object>> h_dex_elements(hs.NewHandle( 5806 mirror::ObjectArray<mirror::Object>::Alloc(self, dex_elements_class, dex_files.size()))); 5807 Handle<mirror::Class> h_dex_element_class = 5808 hs.NewHandle(dex_elements_class->GetComponentType()); 5809 5810 ArtField* element_file_field = 5811 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList__Element_dexFile); 5812 DCHECK_EQ(h_dex_element_class.Get(), element_file_field->GetDeclaringClass()); 5813 5814 ArtField* cookie_field = soa.DecodeField(WellKnownClasses::dalvik_system_DexFile_cookie); 5815 DCHECK_EQ(cookie_field->GetDeclaringClass(), element_file_field->GetType<false>()); 5816 5817 // Fill the elements array. 5818 int32_t index = 0; 5819 for (const DexFile* dex_file : dex_files) { 5820 StackHandleScope<3> hs2(self); 5821 5822 Handle<mirror::LongArray> h_long_array = hs2.NewHandle(mirror::LongArray::Alloc(self, 1)); 5823 DCHECK(h_long_array.Get() != nullptr); 5824 h_long_array->Set(0, reinterpret_cast<intptr_t>(dex_file)); 5825 5826 Handle<mirror::Object> h_dex_file = hs2.NewHandle( 5827 cookie_field->GetDeclaringClass()->AllocObject(self)); 5828 DCHECK(h_dex_file.Get() != nullptr); 5829 cookie_field->SetObject<false>(h_dex_file.Get(), h_long_array.Get()); 5830 5831 Handle<mirror::Object> h_element = hs2.NewHandle(h_dex_element_class->AllocObject(self)); 5832 DCHECK(h_element.Get() != nullptr); 5833 element_file_field->SetObject<false>(h_element.Get(), h_dex_file.Get()); 5834 5835 h_dex_elements->Set(index, h_element.Get()); 5836 index++; 5837 } 5838 DCHECK_EQ(index, h_dex_elements->GetLength()); 5839 5840 // Create DexPathList. 5841 Handle<mirror::Object> h_dex_path_list = hs.NewHandle( 5842 dex_elements_field->GetDeclaringClass()->AllocObject(self)); 5843 DCHECK(h_dex_path_list.Get() != nullptr); 5844 // Set elements. 5845 dex_elements_field->SetObject<false>(h_dex_path_list.Get(), h_dex_elements.Get()); 5846 5847 // Create PathClassLoader. 5848 Handle<mirror::Class> h_path_class_class = hs.NewHandle( 5849 soa.Decode<mirror::Class*>(WellKnownClasses::dalvik_system_PathClassLoader)); 5850 Handle<mirror::Object> h_path_class_loader = hs.NewHandle( 5851 h_path_class_class->AllocObject(self)); 5852 DCHECK(h_path_class_loader.Get() != nullptr); 5853 // Set DexPathList. 5854 ArtField* path_list_field = 5855 soa.DecodeField(WellKnownClasses::dalvik_system_PathClassLoader_pathList); 5856 DCHECK(path_list_field != nullptr); 5857 path_list_field->SetObject<false>(h_path_class_loader.Get(), h_dex_path_list.Get()); 5858 5859 // Make a pretend boot-classpath. 5860 // TODO: Should we scan the image? 5861 ArtField* const parent_field = 5862 mirror::Class::FindField(self, hs.NewHandle(h_path_class_loader->GetClass()), "parent", 5863 "Ljava/lang/ClassLoader;"); 5864 DCHECK(parent_field!= nullptr); 5865 mirror::Object* boot_cl = 5866 soa.Decode<mirror::Class*>(WellKnownClasses::java_lang_BootClassLoader)->AllocObject(self); 5867 parent_field->SetObject<false>(h_path_class_loader.Get(), boot_cl); 5868 5869 // Make it a global ref and return. 5870 ScopedLocalRef<jobject> local_ref( 5871 soa.Env(), soa.Env()->AddLocalReference<jobject>(h_path_class_loader.Get())); 5872 return soa.Env()->NewGlobalRef(local_ref.get()); 5873} 5874 5875ArtMethod* ClassLinker::CreateRuntimeMethod() { 5876 ArtMethod* method = AllocArtMethodArray(Thread::Current(), 1); 5877 CHECK(method != nullptr); 5878 method->SetDexMethodIndex(DexFile::kDexNoIndex); 5879 CHECK(method->IsRuntimeMethod()); 5880 return method; 5881} 5882 5883void ClassLinker::DropFindArrayClassCache() { 5884 std::fill_n(find_array_class_cache_, kFindArrayCacheSize, GcRoot<mirror::Class>(nullptr)); 5885 find_array_class_cache_next_victim_ = 0; 5886} 5887 5888} // namespace art 5889