class_linker.cc revision aafcfca5fe545365ef377fff2897b8a908f03e71
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 "base/casts.h" 30#include "base/logging.h" 31#include "base/scoped_flock.h" 32#include "base/stl_util.h" 33#include "base/unix_file/fd_file.h" 34#include "base/value_object.h" 35#include "class_linker-inl.h" 36#include "compiler_callbacks.h" 37#include "debugger.h" 38#include "dex_file-inl.h" 39#include "entrypoints/runtime_asm_entrypoints.h" 40#include "gc_root-inl.h" 41#include "gc/accounting/card_table-inl.h" 42#include "gc/accounting/heap_bitmap.h" 43#include "gc/heap.h" 44#include "gc/space/image_space.h" 45#include "handle_scope.h" 46#include "intern_table.h" 47#include "interpreter/interpreter.h" 48#include "jit/jit.h" 49#include "jit/jit_code_cache.h" 50#include "leb128.h" 51#include "linear_alloc.h" 52#include "oat.h" 53#include "oat_file.h" 54#include "oat_file_assistant.h" 55#include "object_lock.h" 56#include "mirror/art_method-inl.h" 57#include "mirror/class.h" 58#include "mirror/class-inl.h" 59#include "mirror/class_loader.h" 60#include "mirror/dex_cache-inl.h" 61#include "mirror/field.h" 62#include "mirror/iftable-inl.h" 63#include "mirror/method.h" 64#include "mirror/object-inl.h" 65#include "mirror/object_array-inl.h" 66#include "mirror/proxy.h" 67#include "mirror/reference-inl.h" 68#include "mirror/stack_trace_element.h" 69#include "mirror/string-inl.h" 70#include "os.h" 71#include "runtime.h" 72#include "entrypoints/entrypoint_utils.h" 73#include "ScopedLocalRef.h" 74#include "scoped_thread_state_change.h" 75#include "handle_scope-inl.h" 76#include "thread-inl.h" 77#include "utils.h" 78#include "verifier/method_verifier.h" 79#include "well_known_classes.h" 80 81namespace art { 82 83static constexpr bool kSanityCheckObjects = kIsDebugBuild; 84 85// For b/21333911. 86static constexpr bool kDuplicateClassesCheck = false; 87 88static void ThrowNoClassDefFoundError(const char* fmt, ...) 89 __attribute__((__format__(__printf__, 1, 2))) 90 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 91static void ThrowNoClassDefFoundError(const char* fmt, ...) { 92 va_list args; 93 va_start(args, fmt); 94 Thread* self = Thread::Current(); 95 self->ThrowNewExceptionV("Ljava/lang/NoClassDefFoundError;", fmt, args); 96 va_end(args); 97} 98 99static bool HasInitWithString(Thread* self, ClassLinker* class_linker, const char* descriptor) 100 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 101 mirror::ArtMethod* method = self->GetCurrentMethod(nullptr); 102 StackHandleScope<1> hs(self); 103 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(method != nullptr ? 104 method->GetDeclaringClass()->GetClassLoader() 105 : nullptr)); 106 mirror::Class* exception_class = class_linker->FindClass(self, descriptor, class_loader); 107 108 if (exception_class == nullptr) { 109 // No exc class ~ no <init>-with-string. 110 CHECK(self->IsExceptionPending()); 111 self->ClearException(); 112 return false; 113 } 114 115 mirror::ArtMethod* exception_init_method = 116 exception_class->FindDeclaredDirectMethod("<init>", "(Ljava/lang/String;)V"); 117 return exception_init_method != nullptr; 118} 119 120void ClassLinker::ThrowEarlierClassFailure(mirror::Class* c) { 121 // The class failed to initialize on a previous attempt, so we want to throw 122 // a NoClassDefFoundError (v2 2.17.5). The exception to this rule is if we 123 // failed in verification, in which case v2 5.4.1 says we need to re-throw 124 // the previous error. 125 Runtime* const runtime = Runtime::Current(); 126 if (!runtime->IsAotCompiler()) { // Give info if this occurs at runtime. 127 LOG(INFO) << "Rejecting re-init on previously-failed class " << PrettyClass(c); 128 } 129 130 CHECK(c->IsErroneous()) << PrettyClass(c) << " " << c->GetStatus(); 131 Thread* self = Thread::Current(); 132 if (runtime->IsAotCompiler()) { 133 // At compile time, accurate errors and NCDFE are disabled to speed compilation. 134 mirror::Throwable* pre_allocated = runtime->GetPreAllocatedNoClassDefFoundError(); 135 self->SetException(pre_allocated); 136 } else { 137 if (c->GetVerifyErrorClass() != nullptr) { 138 // TODO: change the verifier to store an _instance_, with a useful detail message? 139 // It's possible the exception doesn't have a <init>(String). 140 std::string temp; 141 const char* descriptor = c->GetVerifyErrorClass()->GetDescriptor(&temp); 142 143 if (HasInitWithString(self, this, descriptor)) { 144 self->ThrowNewException(descriptor, PrettyDescriptor(c).c_str()); 145 } else { 146 self->ThrowNewException(descriptor, nullptr); 147 } 148 } else { 149 self->ThrowNewException("Ljava/lang/NoClassDefFoundError;", 150 PrettyDescriptor(c).c_str()); 151 } 152 } 153} 154 155static void VlogClassInitializationFailure(Handle<mirror::Class> klass) 156 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 157 if (VLOG_IS_ON(class_linker)) { 158 std::string temp; 159 LOG(INFO) << "Failed to initialize class " << klass->GetDescriptor(&temp) << " from " 160 << klass->GetLocation() << "\n" << Thread::Current()->GetException()->Dump(); 161 } 162} 163 164static void WrapExceptionInInitializer(Handle<mirror::Class> klass) 165 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 166 Thread* self = Thread::Current(); 167 JNIEnv* env = self->GetJniEnv(); 168 169 ScopedLocalRef<jthrowable> cause(env, env->ExceptionOccurred()); 170 CHECK(cause.get() != nullptr); 171 172 env->ExceptionClear(); 173 bool is_error = env->IsInstanceOf(cause.get(), WellKnownClasses::java_lang_Error); 174 env->Throw(cause.get()); 175 176 // We only wrap non-Error exceptions; an Error can just be used as-is. 177 if (!is_error) { 178 self->ThrowNewWrappedException("Ljava/lang/ExceptionInInitializerError;", nullptr); 179 } 180 VlogClassInitializationFailure(klass); 181} 182 183// Gap between two fields in object layout. 184struct FieldGap { 185 uint32_t start_offset; // The offset from the start of the object. 186 uint32_t size; // The gap size of 1, 2, or 4 bytes. 187}; 188struct FieldGapsComparator { 189 explicit FieldGapsComparator() { 190 } 191 bool operator() (const FieldGap& lhs, const FieldGap& rhs) 192 NO_THREAD_SAFETY_ANALYSIS { 193 // Sort by gap size, largest first. Secondary sort by starting offset. 194 return lhs.size > rhs.size || (lhs.size == rhs.size && lhs.start_offset < rhs.start_offset); 195 } 196}; 197typedef std::priority_queue<FieldGap, std::vector<FieldGap>, FieldGapsComparator> FieldGaps; 198 199// Adds largest aligned gaps to queue of gaps. 200static void AddFieldGap(uint32_t gap_start, uint32_t gap_end, FieldGaps* gaps) { 201 DCHECK(gaps != nullptr); 202 203 uint32_t current_offset = gap_start; 204 while (current_offset != gap_end) { 205 size_t remaining = gap_end - current_offset; 206 if (remaining >= sizeof(uint32_t) && IsAligned<4>(current_offset)) { 207 gaps->push(FieldGap {current_offset, sizeof(uint32_t)}); 208 current_offset += sizeof(uint32_t); 209 } else if (remaining >= sizeof(uint16_t) && IsAligned<2>(current_offset)) { 210 gaps->push(FieldGap {current_offset, sizeof(uint16_t)}); 211 current_offset += sizeof(uint16_t); 212 } else { 213 gaps->push(FieldGap {current_offset, sizeof(uint8_t)}); 214 current_offset += sizeof(uint8_t); 215 } 216 DCHECK_LE(current_offset, gap_end) << "Overran gap"; 217 } 218} 219// Shuffle fields forward, making use of gaps whenever possible. 220template<int n> 221static void ShuffleForward(size_t* current_field_idx, 222 MemberOffset* field_offset, 223 std::deque<ArtField*>* grouped_and_sorted_fields, 224 FieldGaps* gaps) 225 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 226 DCHECK(current_field_idx != nullptr); 227 DCHECK(grouped_and_sorted_fields != nullptr); 228 DCHECK(gaps != nullptr); 229 DCHECK(field_offset != nullptr); 230 231 DCHECK(IsPowerOfTwo(n)); 232 while (!grouped_and_sorted_fields->empty()) { 233 ArtField* field = grouped_and_sorted_fields->front(); 234 Primitive::Type type = field->GetTypeAsPrimitiveType(); 235 if (Primitive::ComponentSize(type) < n) { 236 break; 237 } 238 if (!IsAligned<n>(field_offset->Uint32Value())) { 239 MemberOffset old_offset = *field_offset; 240 *field_offset = MemberOffset(RoundUp(field_offset->Uint32Value(), n)); 241 AddFieldGap(old_offset.Uint32Value(), field_offset->Uint32Value(), gaps); 242 } 243 CHECK(type != Primitive::kPrimNot) << PrettyField(field); // should be primitive types 244 grouped_and_sorted_fields->pop_front(); 245 if (!gaps->empty() && gaps->top().size >= n) { 246 FieldGap gap = gaps->top(); 247 gaps->pop(); 248 DCHECK(IsAligned<n>(gap.start_offset)); 249 field->SetOffset(MemberOffset(gap.start_offset)); 250 if (gap.size > n) { 251 AddFieldGap(gap.start_offset + n, gap.start_offset + gap.size, gaps); 252 } 253 } else { 254 DCHECK(IsAligned<n>(field_offset->Uint32Value())); 255 field->SetOffset(*field_offset); 256 *field_offset = MemberOffset(field_offset->Uint32Value() + n); 257 } 258 ++(*current_field_idx); 259 } 260} 261 262ClassLinker::ClassLinker(InternTable* intern_table) 263 // dex_lock_ is recursive as it may be used in stack dumping. 264 : dex_lock_("ClassLinker dex lock", kDefaultMutexLevel), 265 dex_cache_image_class_lookup_required_(false), 266 failed_dex_cache_class_lookups_(0), 267 class_roots_(nullptr), 268 array_iftable_(nullptr), 269 find_array_class_cache_next_victim_(0), 270 init_done_(false), 271 log_new_dex_caches_roots_(false), 272 log_new_class_table_roots_(false), 273 intern_table_(intern_table), 274 quick_resolution_trampoline_(nullptr), 275 quick_imt_conflict_trampoline_(nullptr), 276 quick_generic_jni_trampoline_(nullptr), 277 quick_to_interpreter_bridge_trampoline_(nullptr), 278 image_pointer_size_(sizeof(void*)) { 279 CHECK(intern_table_ != nullptr); 280 for (size_t i = 0; i < kFindArrayCacheSize; ++i) { 281 find_array_class_cache_[i] = GcRoot<mirror::Class>(nullptr); 282 } 283} 284 285void ClassLinker::InitWithoutImage(std::vector<std::unique_ptr<const DexFile>> boot_class_path) { 286 VLOG(startup) << "ClassLinker::Init"; 287 CHECK(!Runtime::Current()->GetHeap()->HasImageSpace()) << "Runtime has image. We should use it."; 288 289 CHECK(!init_done_); 290 291 // java_lang_Class comes first, it's needed for AllocClass 292 Thread* const self = Thread::Current(); 293 gc::Heap* const heap = Runtime::Current()->GetHeap(); 294 // The GC can't handle an object with a null class since we can't get the size of this object. 295 heap->IncrementDisableMovingGC(self); 296 StackHandleScope<64> hs(self); // 64 is picked arbitrarily. 297 Handle<mirror::Class> java_lang_Class(hs.NewHandle(down_cast<mirror::Class*>( 298 heap->AllocNonMovableObject<true>(self, nullptr, 299 mirror::Class::ClassClassSize(), 300 VoidFunctor())))); 301 CHECK(java_lang_Class.Get() != nullptr); 302 mirror::Class::SetClassClass(java_lang_Class.Get()); 303 java_lang_Class->SetClass(java_lang_Class.Get()); 304 if (kUseBakerOrBrooksReadBarrier) { 305 java_lang_Class->AssertReadBarrierPointer(); 306 } 307 java_lang_Class->SetClassSize(mirror::Class::ClassClassSize()); 308 java_lang_Class->SetPrimitiveType(Primitive::kPrimNot); 309 heap->DecrementDisableMovingGC(self); 310 // AllocClass(mirror::Class*) can now be used 311 312 // Class[] is used for reflection support. 313 Handle<mirror::Class> class_array_class(hs.NewHandle( 314 AllocClass(self, java_lang_Class.Get(), mirror::ObjectArray<mirror::Class>::ClassSize()))); 315 class_array_class->SetComponentType(java_lang_Class.Get()); 316 317 // java_lang_Object comes next so that object_array_class can be created. 318 Handle<mirror::Class> java_lang_Object(hs.NewHandle( 319 AllocClass(self, java_lang_Class.Get(), mirror::Object::ClassSize()))); 320 CHECK(java_lang_Object.Get() != nullptr); 321 // backfill Object as the super class of Class. 322 java_lang_Class->SetSuperClass(java_lang_Object.Get()); 323 mirror::Class::SetStatus(java_lang_Object, mirror::Class::kStatusLoaded, self); 324 325 // Object[] next to hold class roots. 326 Handle<mirror::Class> object_array_class(hs.NewHandle( 327 AllocClass(self, java_lang_Class.Get(), mirror::ObjectArray<mirror::Object>::ClassSize()))); 328 object_array_class->SetComponentType(java_lang_Object.Get()); 329 330 // Setup the char (primitive) class to be used for char[]. 331 Handle<mirror::Class> char_class(hs.NewHandle( 332 AllocClass(self, java_lang_Class.Get(), mirror::Class::PrimitiveClassSize()))); 333 // The primitive char class won't be initialized by 334 // InitializePrimitiveClass until line 459, but strings (and 335 // internal char arrays) will be allocated before that and the 336 // component size, which is computed from the primitive type, needs 337 // to be set here. 338 char_class->SetPrimitiveType(Primitive::kPrimChar); 339 340 // Setup the char[] class to be used for String. 341 Handle<mirror::Class> char_array_class(hs.NewHandle( 342 AllocClass(self, java_lang_Class.Get(), 343 mirror::Array::ClassSize()))); 344 char_array_class->SetComponentType(char_class.Get()); 345 mirror::CharArray::SetArrayClass(char_array_class.Get()); 346 347 // Setup String. 348 Handle<mirror::Class> java_lang_String(hs.NewHandle( 349 AllocClass(self, java_lang_Class.Get(), mirror::String::ClassSize()))); 350 mirror::String::SetClass(java_lang_String.Get()); 351 mirror::Class::SetStatus(java_lang_String, mirror::Class::kStatusResolved, self); 352 java_lang_String->SetStringClass(); 353 354 // Setup java.lang.ref.Reference. 355 Handle<mirror::Class> java_lang_ref_Reference(hs.NewHandle( 356 AllocClass(self, java_lang_Class.Get(), mirror::Reference::ClassSize()))); 357 mirror::Reference::SetClass(java_lang_ref_Reference.Get()); 358 java_lang_ref_Reference->SetObjectSize(mirror::Reference::InstanceSize()); 359 mirror::Class::SetStatus(java_lang_ref_Reference, mirror::Class::kStatusResolved, self); 360 361 // Create storage for root classes, save away our work so far (requires descriptors). 362 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class>>( 363 mirror::ObjectArray<mirror::Class>::Alloc(self, object_array_class.Get(), 364 kClassRootsMax)); 365 CHECK(!class_roots_.IsNull()); 366 SetClassRoot(kJavaLangClass, java_lang_Class.Get()); 367 SetClassRoot(kJavaLangObject, java_lang_Object.Get()); 368 SetClassRoot(kClassArrayClass, class_array_class.Get()); 369 SetClassRoot(kObjectArrayClass, object_array_class.Get()); 370 SetClassRoot(kCharArrayClass, char_array_class.Get()); 371 SetClassRoot(kJavaLangString, java_lang_String.Get()); 372 SetClassRoot(kJavaLangRefReference, java_lang_ref_Reference.Get()); 373 374 // Setup the primitive type classes. 375 SetClassRoot(kPrimitiveBoolean, CreatePrimitiveClass(self, Primitive::kPrimBoolean)); 376 SetClassRoot(kPrimitiveByte, CreatePrimitiveClass(self, Primitive::kPrimByte)); 377 SetClassRoot(kPrimitiveShort, CreatePrimitiveClass(self, Primitive::kPrimShort)); 378 SetClassRoot(kPrimitiveInt, CreatePrimitiveClass(self, Primitive::kPrimInt)); 379 SetClassRoot(kPrimitiveLong, CreatePrimitiveClass(self, Primitive::kPrimLong)); 380 SetClassRoot(kPrimitiveFloat, CreatePrimitiveClass(self, Primitive::kPrimFloat)); 381 SetClassRoot(kPrimitiveDouble, CreatePrimitiveClass(self, Primitive::kPrimDouble)); 382 SetClassRoot(kPrimitiveVoid, CreatePrimitiveClass(self, Primitive::kPrimVoid)); 383 384 // Create array interface entries to populate once we can load system classes. 385 array_iftable_ = GcRoot<mirror::IfTable>(AllocIfTable(self, 2)); 386 387 // Create int array type for AllocDexCache (done in AppendToBootClassPath). 388 Handle<mirror::Class> int_array_class(hs.NewHandle( 389 AllocClass(self, java_lang_Class.Get(), mirror::Array::ClassSize()))); 390 int_array_class->SetComponentType(GetClassRoot(kPrimitiveInt)); 391 mirror::IntArray::SetArrayClass(int_array_class.Get()); 392 SetClassRoot(kIntArrayClass, int_array_class.Get()); 393 394 // Create long array type for AllocDexCache (done in AppendToBootClassPath). 395 Handle<mirror::Class> long_array_class(hs.NewHandle( 396 AllocClass(self, java_lang_Class.Get(), mirror::Array::ClassSize()))); 397 long_array_class->SetComponentType(GetClassRoot(kPrimitiveLong)); 398 mirror::LongArray::SetArrayClass(long_array_class.Get()); 399 SetClassRoot(kLongArrayClass, long_array_class.Get()); 400 401 // now that these are registered, we can use AllocClass() and AllocObjectArray 402 403 // Set up DexCache. This cannot be done later since AppendToBootClassPath calls AllocDexCache. 404 Handle<mirror::Class> java_lang_DexCache(hs.NewHandle( 405 AllocClass(self, java_lang_Class.Get(), mirror::DexCache::ClassSize()))); 406 SetClassRoot(kJavaLangDexCache, java_lang_DexCache.Get()); 407 java_lang_DexCache->SetObjectSize(mirror::DexCache::InstanceSize()); 408 mirror::Class::SetStatus(java_lang_DexCache, mirror::Class::kStatusResolved, self); 409 410 // Constructor, Method, and AbstractMethod are necessary so 411 // that FindClass can link members. 412 413 Handle<mirror::Class> java_lang_reflect_ArtMethod(hs.NewHandle( 414 AllocClass(self, java_lang_Class.Get(), mirror::ArtMethod::ClassSize()))); 415 CHECK(java_lang_reflect_ArtMethod.Get() != nullptr); 416 size_t pointer_size = GetInstructionSetPointerSize(Runtime::Current()->GetInstructionSet()); 417 java_lang_reflect_ArtMethod->SetObjectSize(mirror::ArtMethod::InstanceSize(pointer_size)); 418 SetClassRoot(kJavaLangReflectArtMethod, java_lang_reflect_ArtMethod.Get()); 419 mirror::Class::SetStatus(java_lang_reflect_ArtMethod, mirror::Class::kStatusResolved, self); 420 mirror::ArtMethod::SetClass(java_lang_reflect_ArtMethod.Get()); 421 422 // Set up array classes for string, field, method 423 Handle<mirror::Class> object_array_string(hs.NewHandle( 424 AllocClass(self, java_lang_Class.Get(), 425 mirror::ObjectArray<mirror::String>::ClassSize()))); 426 object_array_string->SetComponentType(java_lang_String.Get()); 427 SetClassRoot(kJavaLangStringArrayClass, object_array_string.Get()); 428 429 Handle<mirror::Class> object_array_art_method(hs.NewHandle( 430 AllocClass(self, java_lang_Class.Get(), 431 mirror::ObjectArray<mirror::ArtMethod>::ClassSize()))); 432 object_array_art_method->SetComponentType(java_lang_reflect_ArtMethod.Get()); 433 SetClassRoot(kJavaLangReflectArtMethodArrayClass, object_array_art_method.Get()); 434 435 // Setup boot_class_path_ and register class_path now that we can use AllocObjectArray to create 436 // DexCache instances. Needs to be after String, Field, Method arrays since AllocDexCache uses 437 // these roots. 438 CHECK_NE(0U, boot_class_path.size()); 439 for (auto& dex_file : boot_class_path) { 440 CHECK(dex_file.get() != nullptr); 441 AppendToBootClassPath(self, *dex_file); 442 opened_dex_files_.push_back(std::move(dex_file)); 443 } 444 445 // now we can use FindSystemClass 446 447 // run char class through InitializePrimitiveClass to finish init 448 InitializePrimitiveClass(char_class.Get(), Primitive::kPrimChar); 449 SetClassRoot(kPrimitiveChar, char_class.Get()); // needs descriptor 450 451 // Create runtime resolution and imt conflict methods. Also setup the default imt. 452 Runtime* runtime = Runtime::Current(); 453 runtime->SetResolutionMethod(runtime->CreateResolutionMethod()); 454 runtime->SetImtConflictMethod(runtime->CreateImtConflictMethod()); 455 runtime->SetImtUnimplementedMethod(runtime->CreateImtConflictMethod()); 456 runtime->SetDefaultImt(runtime->CreateDefaultImt(this)); 457 458 // Set up GenericJNI entrypoint. That is mainly a hack for common_compiler_test.h so that 459 // we do not need friend classes or a publicly exposed setter. 460 quick_generic_jni_trampoline_ = GetQuickGenericJniStub(); 461 if (!runtime->IsAotCompiler()) { 462 // We need to set up the generic trampolines since we don't have an image. 463 quick_resolution_trampoline_ = GetQuickResolutionStub(); 464 quick_imt_conflict_trampoline_ = GetQuickImtConflictStub(); 465 quick_to_interpreter_bridge_trampoline_ = GetQuickToInterpreterBridge(); 466 } 467 468 // Object, String and DexCache need to be rerun through FindSystemClass to finish init 469 mirror::Class::SetStatus(java_lang_Object, mirror::Class::kStatusNotReady, self); 470 CHECK_EQ(java_lang_Object.Get(), FindSystemClass(self, "Ljava/lang/Object;")); 471 CHECK_EQ(java_lang_Object->GetObjectSize(), mirror::Object::InstanceSize()); 472 mirror::Class::SetStatus(java_lang_String, mirror::Class::kStatusNotReady, self); 473 mirror::Class* String_class = FindSystemClass(self, "Ljava/lang/String;"); 474 if (java_lang_String.Get() != String_class) { 475 std::ostringstream os1, os2; 476 java_lang_String->DumpClass(os1, mirror::Class::kDumpClassFullDetail); 477 String_class->DumpClass(os2, mirror::Class::kDumpClassFullDetail); 478 LOG(FATAL) << os1.str() << "\n\n" << os2.str(); 479 } 480 mirror::Class::SetStatus(java_lang_DexCache, mirror::Class::kStatusNotReady, self); 481 CHECK_EQ(java_lang_DexCache.Get(), FindSystemClass(self, "Ljava/lang/DexCache;")); 482 CHECK_EQ(java_lang_DexCache->GetObjectSize(), mirror::DexCache::InstanceSize()); 483 484 // Setup the primitive array type classes - can't be done until Object has a vtable. 485 SetClassRoot(kBooleanArrayClass, FindSystemClass(self, "[Z")); 486 mirror::BooleanArray::SetArrayClass(GetClassRoot(kBooleanArrayClass)); 487 488 SetClassRoot(kByteArrayClass, FindSystemClass(self, "[B")); 489 mirror::ByteArray::SetArrayClass(GetClassRoot(kByteArrayClass)); 490 491 CHECK_EQ(char_array_class.Get(), FindSystemClass(self, "[C")); 492 493 SetClassRoot(kShortArrayClass, FindSystemClass(self, "[S")); 494 mirror::ShortArray::SetArrayClass(GetClassRoot(kShortArrayClass)); 495 496 CHECK_EQ(int_array_class.Get(), FindSystemClass(self, "[I")); 497 498 CHECK_EQ(long_array_class.Get(), FindSystemClass(self, "[J")); 499 500 SetClassRoot(kFloatArrayClass, FindSystemClass(self, "[F")); 501 mirror::FloatArray::SetArrayClass(GetClassRoot(kFloatArrayClass)); 502 503 SetClassRoot(kDoubleArrayClass, FindSystemClass(self, "[D")); 504 mirror::DoubleArray::SetArrayClass(GetClassRoot(kDoubleArrayClass)); 505 506 CHECK_EQ(class_array_class.Get(), FindSystemClass(self, "[Ljava/lang/Class;")); 507 508 CHECK_EQ(object_array_class.Get(), FindSystemClass(self, "[Ljava/lang/Object;")); 509 510 // Setup the single, global copy of "iftable". 511 auto java_lang_Cloneable = hs.NewHandle(FindSystemClass(self, "Ljava/lang/Cloneable;")); 512 CHECK(java_lang_Cloneable.Get() != nullptr); 513 auto java_io_Serializable = hs.NewHandle(FindSystemClass(self, "Ljava/io/Serializable;")); 514 CHECK(java_io_Serializable.Get() != nullptr); 515 // We assume that Cloneable/Serializable don't have superinterfaces -- normally we'd have to 516 // crawl up and explicitly list all of the supers as well. 517 array_iftable_.Read()->SetInterface(0, java_lang_Cloneable.Get()); 518 array_iftable_.Read()->SetInterface(1, java_io_Serializable.Get()); 519 520 // Sanity check Class[] and Object[]'s interfaces. GetDirectInterface may cause thread 521 // suspension. 522 CHECK_EQ(java_lang_Cloneable.Get(), 523 mirror::Class::GetDirectInterface(self, class_array_class, 0)); 524 CHECK_EQ(java_io_Serializable.Get(), 525 mirror::Class::GetDirectInterface(self, class_array_class, 1)); 526 CHECK_EQ(java_lang_Cloneable.Get(), 527 mirror::Class::GetDirectInterface(self, object_array_class, 0)); 528 CHECK_EQ(java_io_Serializable.Get(), 529 mirror::Class::GetDirectInterface(self, object_array_class, 1)); 530 // Run Class, ArtField, and ArtMethod through FindSystemClass. This initializes their 531 // dex_cache_ fields and register them in class_table_. 532 CHECK_EQ(java_lang_Class.Get(), FindSystemClass(self, "Ljava/lang/Class;")); 533 534 mirror::Class::SetStatus(java_lang_reflect_ArtMethod, mirror::Class::kStatusNotReady, self); 535 CHECK_EQ(java_lang_reflect_ArtMethod.Get(), 536 FindSystemClass(self, "Ljava/lang/reflect/ArtMethod;")); 537 CHECK_EQ(object_array_string.Get(), 538 FindSystemClass(self, GetClassRootDescriptor(kJavaLangStringArrayClass))); 539 CHECK_EQ(object_array_art_method.Get(), 540 FindSystemClass(self, GetClassRootDescriptor(kJavaLangReflectArtMethodArrayClass))); 541 542 // End of special init trickery, subsequent classes may be loaded via FindSystemClass. 543 544 // Create java.lang.reflect.Proxy root. 545 SetClassRoot(kJavaLangReflectProxy, FindSystemClass(self, "Ljava/lang/reflect/Proxy;")); 546 547 // Create java.lang.reflect.Field.class root. 548 auto* class_root = FindSystemClass(self, "Ljava/lang/reflect/Field;"); 549 CHECK(class_root != nullptr); 550 SetClassRoot(kJavaLangReflectField, class_root); 551 mirror::Field::SetClass(class_root); 552 553 // Create java.lang.reflect.Field array root. 554 class_root = FindSystemClass(self, "[Ljava/lang/reflect/Field;"); 555 CHECK(class_root != nullptr); 556 SetClassRoot(kJavaLangReflectFieldArrayClass, class_root); 557 mirror::Field::SetArrayClass(class_root); 558 559 // Create java.lang.reflect.Constructor.class root and array root. 560 class_root = FindSystemClass(self, "Ljava/lang/reflect/Constructor;"); 561 CHECK(class_root != nullptr); 562 SetClassRoot(kJavaLangReflectConstructor, class_root); 563 mirror::Constructor::SetClass(class_root); 564 class_root = FindSystemClass(self, "[Ljava/lang/reflect/Constructor;"); 565 CHECK(class_root != nullptr); 566 SetClassRoot(kJavaLangReflectConstructorArrayClass, class_root); 567 mirror::Constructor::SetArrayClass(class_root); 568 569 // Create java.lang.reflect.Method.class root and array root. 570 class_root = FindSystemClass(self, "Ljava/lang/reflect/Method;"); 571 CHECK(class_root != nullptr); 572 SetClassRoot(kJavaLangReflectMethod, class_root); 573 mirror::Method::SetClass(class_root); 574 class_root = FindSystemClass(self, "[Ljava/lang/reflect/Method;"); 575 CHECK(class_root != nullptr); 576 SetClassRoot(kJavaLangReflectMethodArrayClass, class_root); 577 mirror::Method::SetArrayClass(class_root); 578 579 // java.lang.ref classes need to be specially flagged, but otherwise are normal classes 580 // finish initializing Reference class 581 mirror::Class::SetStatus(java_lang_ref_Reference, mirror::Class::kStatusNotReady, self); 582 CHECK_EQ(java_lang_ref_Reference.Get(), FindSystemClass(self, "Ljava/lang/ref/Reference;")); 583 CHECK_EQ(java_lang_ref_Reference->GetObjectSize(), mirror::Reference::InstanceSize()); 584 CHECK_EQ(java_lang_ref_Reference->GetClassSize(), mirror::Reference::ClassSize()); 585 class_root = FindSystemClass(self, "Ljava/lang/ref/FinalizerReference;"); 586 class_root->SetAccessFlags(class_root->GetAccessFlags() | 587 kAccClassIsReference | kAccClassIsFinalizerReference); 588 class_root = FindSystemClass(self, "Ljava/lang/ref/PhantomReference;"); 589 class_root->SetAccessFlags(class_root->GetAccessFlags() | kAccClassIsReference | 590 kAccClassIsPhantomReference); 591 class_root = FindSystemClass(self, "Ljava/lang/ref/SoftReference;"); 592 class_root->SetAccessFlags(class_root->GetAccessFlags() | kAccClassIsReference); 593 class_root = FindSystemClass(self, "Ljava/lang/ref/WeakReference;"); 594 class_root->SetAccessFlags(class_root->GetAccessFlags() | kAccClassIsReference | 595 kAccClassIsWeakReference); 596 597 // Setup the ClassLoader, verifying the object_size_. 598 class_root = FindSystemClass(self, "Ljava/lang/ClassLoader;"); 599 CHECK_EQ(class_root->GetObjectSize(), mirror::ClassLoader::InstanceSize()); 600 SetClassRoot(kJavaLangClassLoader, class_root); 601 602 // Set up java.lang.Throwable, java.lang.ClassNotFoundException, and 603 // java.lang.StackTraceElement as a convenience. 604 SetClassRoot(kJavaLangThrowable, FindSystemClass(self, "Ljava/lang/Throwable;")); 605 mirror::Throwable::SetClass(GetClassRoot(kJavaLangThrowable)); 606 SetClassRoot(kJavaLangClassNotFoundException, 607 FindSystemClass(self, "Ljava/lang/ClassNotFoundException;")); 608 SetClassRoot(kJavaLangStackTraceElement, FindSystemClass(self, "Ljava/lang/StackTraceElement;")); 609 SetClassRoot(kJavaLangStackTraceElementArrayClass, 610 FindSystemClass(self, "[Ljava/lang/StackTraceElement;")); 611 mirror::StackTraceElement::SetClass(GetClassRoot(kJavaLangStackTraceElement)); 612 613 // Ensure void type is resolved in the core's dex cache so java.lang.Void is correctly 614 // initialized. 615 { 616 const DexFile& dex_file = java_lang_Object->GetDexFile(); 617 const DexFile::StringId* void_string_id = dex_file.FindStringId("V"); 618 CHECK(void_string_id != nullptr); 619 uint32_t void_string_index = dex_file.GetIndexForStringId(*void_string_id); 620 const DexFile::TypeId* void_type_id = dex_file.FindTypeId(void_string_index); 621 CHECK(void_type_id != nullptr); 622 uint16_t void_type_idx = dex_file.GetIndexForTypeId(*void_type_id); 623 // Now we resolve void type so the dex cache contains it. We use java.lang.Object class 624 // as referrer so the used dex cache is core's one. 625 mirror::Class* resolved_type = ResolveType(dex_file, void_type_idx, java_lang_Object.Get()); 626 CHECK_EQ(resolved_type, GetClassRoot(kPrimitiveVoid)); 627 self->AssertNoPendingException(); 628 } 629 630 FinishInit(self); 631 632 VLOG(startup) << "ClassLinker::InitFromCompiler exiting"; 633} 634 635void ClassLinker::FinishInit(Thread* self) { 636 VLOG(startup) << "ClassLinker::FinishInit entering"; 637 638 // Let the heap know some key offsets into java.lang.ref instances 639 // Note: we hard code the field indexes here rather than using FindInstanceField 640 // as the types of the field can't be resolved prior to the runtime being 641 // fully initialized 642 mirror::Class* java_lang_ref_Reference = GetClassRoot(kJavaLangRefReference); 643 mirror::Class* java_lang_ref_FinalizerReference = 644 FindSystemClass(self, "Ljava/lang/ref/FinalizerReference;"); 645 646 ArtField* pendingNext = java_lang_ref_Reference->GetInstanceField(0); 647 CHECK_STREQ(pendingNext->GetName(), "pendingNext"); 648 CHECK_STREQ(pendingNext->GetTypeDescriptor(), "Ljava/lang/ref/Reference;"); 649 650 ArtField* queue = java_lang_ref_Reference->GetInstanceField(1); 651 CHECK_STREQ(queue->GetName(), "queue"); 652 CHECK_STREQ(queue->GetTypeDescriptor(), "Ljava/lang/ref/ReferenceQueue;"); 653 654 ArtField* queueNext = java_lang_ref_Reference->GetInstanceField(2); 655 CHECK_STREQ(queueNext->GetName(), "queueNext"); 656 CHECK_STREQ(queueNext->GetTypeDescriptor(), "Ljava/lang/ref/Reference;"); 657 658 ArtField* referent = java_lang_ref_Reference->GetInstanceField(3); 659 CHECK_STREQ(referent->GetName(), "referent"); 660 CHECK_STREQ(referent->GetTypeDescriptor(), "Ljava/lang/Object;"); 661 662 ArtField* zombie = java_lang_ref_FinalizerReference->GetInstanceField(2); 663 CHECK_STREQ(zombie->GetName(), "zombie"); 664 CHECK_STREQ(zombie->GetTypeDescriptor(), "Ljava/lang/Object;"); 665 666 // ensure all class_roots_ are initialized 667 for (size_t i = 0; i < kClassRootsMax; i++) { 668 ClassRoot class_root = static_cast<ClassRoot>(i); 669 mirror::Class* klass = GetClassRoot(class_root); 670 CHECK(klass != nullptr); 671 DCHECK(klass->IsArrayClass() || klass->IsPrimitive() || klass->GetDexCache() != nullptr); 672 // note SetClassRoot does additional validation. 673 // if possible add new checks there to catch errors early 674 } 675 676 CHECK(!array_iftable_.IsNull()); 677 678 // disable the slow paths in FindClass and CreatePrimitiveClass now 679 // that Object, Class, and Object[] are setup 680 init_done_ = true; 681 682 VLOG(startup) << "ClassLinker::FinishInit exiting"; 683} 684 685void ClassLinker::RunRootClinits() { 686 Thread* self = Thread::Current(); 687 for (size_t i = 0; i < ClassLinker::kClassRootsMax; ++i) { 688 mirror::Class* c = GetClassRoot(ClassRoot(i)); 689 if (!c->IsArrayClass() && !c->IsPrimitive()) { 690 StackHandleScope<1> hs(self); 691 Handle<mirror::Class> h_class(hs.NewHandle(GetClassRoot(ClassRoot(i)))); 692 EnsureInitialized(self, h_class, true, true); 693 self->AssertNoPendingException(); 694 } 695 } 696} 697 698const OatFile* ClassLinker::RegisterOatFile(const OatFile* oat_file) { 699 WriterMutexLock mu(Thread::Current(), dex_lock_); 700 if (kIsDebugBuild) { 701 for (size_t i = 0; i < oat_files_.size(); ++i) { 702 CHECK_NE(oat_file, oat_files_[i]) << oat_file->GetLocation(); 703 } 704 } 705 VLOG(class_linker) << "Registering " << oat_file->GetLocation(); 706 oat_files_.push_back(oat_file); 707 return oat_file; 708} 709 710OatFile& ClassLinker::GetImageOatFile(gc::space::ImageSpace* space) { 711 VLOG(startup) << "ClassLinker::GetImageOatFile entering"; 712 OatFile* oat_file = space->ReleaseOatFile(); 713 CHECK_EQ(RegisterOatFile(oat_file), oat_file); 714 VLOG(startup) << "ClassLinker::GetImageOatFile exiting"; 715 return *oat_file; 716} 717 718class DexFileAndClassPair : ValueObject { 719 public: 720 DexFileAndClassPair(const DexFile* dex_file, size_t current_class_index, bool from_loaded_oat) 721 : cached_descriptor_(GetClassDescriptor(dex_file, current_class_index)), 722 dex_file_(dex_file), 723 current_class_index_(current_class_index), 724 from_loaded_oat_(from_loaded_oat) {} 725 726 DexFileAndClassPair(const DexFileAndClassPair&) = default; 727 728 DexFileAndClassPair& operator=(const DexFileAndClassPair& rhs) { 729 cached_descriptor_ = rhs.cached_descriptor_; 730 dex_file_ = rhs.dex_file_; 731 current_class_index_ = rhs.current_class_index_; 732 from_loaded_oat_ = rhs.from_loaded_oat_; 733 return *this; 734 } 735 736 const char* GetCachedDescriptor() const { 737 return cached_descriptor_; 738 } 739 740 bool operator<(const DexFileAndClassPair& rhs) const { 741 const char* lhsDescriptor = cached_descriptor_; 742 const char* rhsDescriptor = rhs.cached_descriptor_; 743 int cmp = strcmp(lhsDescriptor, rhsDescriptor); 744 if (cmp != 0) { 745 // Note that the order must be reversed. We want to iterate over the classes in dex files. 746 // They are sorted lexicographically. Thus, the priority-queue must be a min-queue. 747 return cmp > 0; 748 } 749 return dex_file_ < rhs.dex_file_; 750 } 751 752 bool DexFileHasMoreClasses() const { 753 return current_class_index_ + 1 < dex_file_->NumClassDefs(); 754 } 755 756 DexFileAndClassPair GetNext() const { 757 return DexFileAndClassPair(dex_file_, current_class_index_ + 1, from_loaded_oat_); 758 } 759 760 size_t GetCurrentClassIndex() const { 761 return current_class_index_; 762 } 763 764 bool FromLoadedOat() const { 765 return from_loaded_oat_; 766 } 767 768 const DexFile* GetDexFile() const { 769 return dex_file_; 770 } 771 772 void DeleteDexFile() { 773 delete dex_file_; 774 dex_file_ = nullptr; 775 } 776 777 private: 778 static const char* GetClassDescriptor(const DexFile* dex_file, size_t index) { 779 const DexFile::ClassDef& class_def = dex_file->GetClassDef(static_cast<uint16_t>(index)); 780 return dex_file->StringByTypeIdx(class_def.class_idx_); 781 } 782 783 const char* cached_descriptor_; 784 const DexFile* dex_file_; 785 size_t current_class_index_; 786 bool from_loaded_oat_; // We only need to compare mismatches between what we load now 787 // and what was loaded before. Any old duplicates must have been 788 // OK, and any new "internal" duplicates are as well (they must 789 // be from multidex, which resolves correctly). 790}; 791 792static void AddDexFilesFromOat(const OatFile* oat_file, bool already_loaded, 793 std::priority_queue<DexFileAndClassPair>* heap) { 794 const std::vector<const OatDexFile*>& oat_dex_files = oat_file->GetOatDexFiles(); 795 for (const OatDexFile* oat_dex_file : oat_dex_files) { 796 std::string error; 797 std::unique_ptr<const DexFile> dex_file = oat_dex_file->OpenDexFile(&error); 798 if (dex_file.get() == nullptr) { 799 LOG(WARNING) << "Could not create dex file from oat file: " << error; 800 } else { 801 if (dex_file->NumClassDefs() > 0U) { 802 heap->emplace(dex_file.release(), 0U, already_loaded); 803 } 804 } 805 } 806} 807 808static void AddNext(DexFileAndClassPair* original, 809 std::priority_queue<DexFileAndClassPair>* heap) { 810 if (original->DexFileHasMoreClasses()) { 811 heap->push(original->GetNext()); 812 } else { 813 // Need to delete the dex file. 814 original->DeleteDexFile(); 815 } 816} 817 818static void FreeDexFilesInHeap(std::priority_queue<DexFileAndClassPair>* heap) { 819 while (!heap->empty()) { 820 delete heap->top().GetDexFile(); 821 heap->pop(); 822 } 823} 824 825const OatFile* ClassLinker::GetBootOatFile() { 826 // To grab the boot oat, look at the dex files in the boot classpath. Any of those is fine, as 827 // they were all compiled into the same oat file. So grab the first one, which is guaranteed to 828 // exist if the boot class-path isn't empty. 829 if (boot_class_path_.empty()) { 830 return nullptr; 831 } 832 const DexFile* boot_dex_file = boot_class_path_[0]; 833 // Is it from an oat file? 834 if (boot_dex_file->GetOatDexFile() != nullptr) { 835 return boot_dex_file->GetOatDexFile()->GetOatFile(); 836 } 837 return nullptr; 838} 839 840const OatFile* ClassLinker::GetPrimaryOatFile() { 841 ReaderMutexLock mu(Thread::Current(), dex_lock_); 842 const OatFile* boot_oat_file = GetBootOatFile(); 843 if (boot_oat_file != nullptr) { 844 for (const OatFile* oat_file : oat_files_) { 845 if (oat_file != boot_oat_file) { 846 return oat_file; 847 } 848 } 849 } 850 return nullptr; 851} 852 853// Check for class-def collisions in dex files. 854// 855// This works by maintaining a heap with one class from each dex file, sorted by the class 856// descriptor. Then a dex-file/class pair is continually removed from the heap and compared 857// against the following top element. If the descriptor is the same, it is now checked whether 858// the two elements agree on whether their dex file was from an already-loaded oat-file or the 859// new oat file. Any disagreement indicates a collision. 860bool ClassLinker::HasCollisions(const OatFile* oat_file, std::string* error_msg) { 861 if (!kDuplicateClassesCheck) { 862 return false; 863 } 864 865 // Dex files are registered late - once a class is actually being loaded. We have to compare 866 // against the open oat files. Take the dex_lock_ that protects oat_files_ accesses. 867 ReaderMutexLock mu(Thread::Current(), dex_lock_); 868 869 std::priority_queue<DexFileAndClassPair> queue; 870 871 // Add dex files from already loaded oat files, but skip boot. 872 { 873 const OatFile* boot_oat = GetBootOatFile(); 874 for (const OatFile* loaded_oat_file : oat_files_) { 875 if (loaded_oat_file == boot_oat) { 876 continue; 877 } 878 AddDexFilesFromOat(loaded_oat_file, true, &queue); 879 } 880 } 881 882 if (queue.empty()) { 883 // No other oat files, return early. 884 return false; 885 } 886 887 // Add dex files from the oat file to check. 888 AddDexFilesFromOat(oat_file, false, &queue); 889 890 // Now drain the queue. 891 while (!queue.empty()) { 892 DexFileAndClassPair compare_pop = queue.top(); 893 queue.pop(); 894 895 // Compare against the following elements. 896 while (!queue.empty()) { 897 DexFileAndClassPair top = queue.top(); 898 899 if (strcmp(compare_pop.GetCachedDescriptor(), top.GetCachedDescriptor()) == 0) { 900 // Same descriptor. Check whether it's crossing old-oat-files to new-oat-files. 901 if (compare_pop.FromLoadedOat() != top.FromLoadedOat()) { 902 *error_msg = 903 StringPrintf("Found duplicated class when checking oat files: '%s' in %s and %s", 904 compare_pop.GetCachedDescriptor(), 905 compare_pop.GetDexFile()->GetLocation().c_str(), 906 top.GetDexFile()->GetLocation().c_str()); 907 FreeDexFilesInHeap(&queue); 908 return true; 909 } 910 // Pop it. 911 queue.pop(); 912 AddNext(&top, &queue); 913 } else { 914 // Something else. Done here. 915 break; 916 } 917 } 918 AddNext(&compare_pop, &queue); 919 } 920 921 return false; 922} 923 924std::vector<std::unique_ptr<const DexFile>> ClassLinker::OpenDexFilesFromOat( 925 const char* dex_location, const char* oat_location, 926 std::vector<std::string>* error_msgs) { 927 CHECK(error_msgs != nullptr); 928 929 // Verify we aren't holding the mutator lock, which could starve GC if we 930 // have to generate or relocate an oat file. 931 Locks::mutator_lock_->AssertNotHeld(Thread::Current()); 932 933 OatFileAssistant oat_file_assistant(dex_location, oat_location, kRuntimeISA, 934 !Runtime::Current()->IsAotCompiler()); 935 936 // Lock the target oat location to avoid races generating and loading the 937 // oat file. 938 std::string error_msg; 939 if (!oat_file_assistant.Lock(&error_msg)) { 940 // Don't worry too much if this fails. If it does fail, it's unlikely we 941 // can generate an oat file anyway. 942 VLOG(class_linker) << "OatFileAssistant::Lock: " << error_msg; 943 } 944 945 // Check if we already have an up-to-date oat file open. 946 const OatFile* source_oat_file = nullptr; 947 { 948 ReaderMutexLock mu(Thread::Current(), dex_lock_); 949 for (const OatFile* oat_file : oat_files_) { 950 CHECK(oat_file != nullptr); 951 if (oat_file_assistant.GivenOatFileIsUpToDate(*oat_file)) { 952 source_oat_file = oat_file; 953 break; 954 } 955 } 956 } 957 958 // If we didn't have an up-to-date oat file open, try to load one from disk. 959 if (source_oat_file == nullptr) { 960 // Update the oat file on disk if we can. This may fail, but that's okay. 961 // Best effort is all that matters here. 962 if (!oat_file_assistant.MakeUpToDate(&error_msg)) { 963 LOG(WARNING) << error_msg; 964 } 965 966 // Get the oat file on disk. 967 std::unique_ptr<OatFile> oat_file = oat_file_assistant.GetBestOatFile(); 968 if (oat_file.get() != nullptr) { 969 // Take the file only if it has no collisions, or we must take it because of preopting. 970 bool accept_oat_file = !HasCollisions(oat_file.get(), &error_msg); 971 if (!accept_oat_file) { 972 // Failed the collision check. Print warning. 973 if (Runtime::Current()->IsDexFileFallbackEnabled()) { 974 LOG(WARNING) << "Found duplicate classes, falling back to interpreter mode for " 975 << dex_location; 976 } else { 977 LOG(WARNING) << "Found duplicate classes, dex-file-fallback disabled, will be failing to " 978 " load classes for " << dex_location; 979 } 980 LOG(WARNING) << error_msg; 981 982 // However, if the app was part of /system and preopted, there is no original dex file 983 // available. In that case grudgingly accept the oat file. 984 if (!DexFile::MaybeDex(dex_location)) { 985 accept_oat_file = true; 986 LOG(WARNING) << "Dex location " << dex_location << " does not seem to include dex file. " 987 << "Allow oat file use. This is potentially dangerous."; 988 } 989 } 990 991 if (accept_oat_file) { 992 source_oat_file = oat_file.release(); 993 RegisterOatFile(source_oat_file); 994 } 995 } 996 } 997 998 std::vector<std::unique_ptr<const DexFile>> dex_files; 999 1000 // Load the dex files from the oat file. 1001 if (source_oat_file != nullptr) { 1002 dex_files = oat_file_assistant.LoadDexFiles(*source_oat_file, dex_location); 1003 if (dex_files.empty()) { 1004 error_msgs->push_back("Failed to open dex files from " 1005 + source_oat_file->GetLocation()); 1006 } 1007 } 1008 1009 // Fall back to running out of the original dex file if we couldn't load any 1010 // dex_files from the oat file. 1011 if (dex_files.empty()) { 1012 if (Runtime::Current()->IsDexFileFallbackEnabled()) { 1013 if (!DexFile::Open(dex_location, dex_location, &error_msg, &dex_files)) { 1014 LOG(WARNING) << error_msg; 1015 error_msgs->push_back("Failed to open dex files from " + std::string(dex_location)); 1016 } 1017 } else { 1018 error_msgs->push_back("Fallback mode disabled, skipping dex files."); 1019 } 1020 } 1021 return dex_files; 1022} 1023 1024const OatFile* ClassLinker::FindOpenedOatFileFromOatLocation(const std::string& oat_location) { 1025 ReaderMutexLock mu(Thread::Current(), dex_lock_); 1026 for (size_t i = 0; i < oat_files_.size(); i++) { 1027 const OatFile* oat_file = oat_files_[i]; 1028 DCHECK(oat_file != nullptr); 1029 if (oat_file->GetLocation() == oat_location) { 1030 return oat_file; 1031 } 1032 } 1033 return nullptr; 1034} 1035 1036void ClassLinker::InitFromImageInterpretOnlyCallback(mirror::Object* obj, void* arg) { 1037 ClassLinker* class_linker = reinterpret_cast<ClassLinker*>(arg); 1038 DCHECK(obj != nullptr); 1039 DCHECK(class_linker != nullptr); 1040 if (obj->IsArtMethod()) { 1041 mirror::ArtMethod* method = obj->AsArtMethod(); 1042 if (!method->IsNative()) { 1043 const size_t pointer_size = class_linker->image_pointer_size_; 1044 method->SetEntryPointFromInterpreterPtrSize(artInterpreterToInterpreterBridge, pointer_size); 1045 if (!method->IsRuntimeMethod() && method != Runtime::Current()->GetResolutionMethod()) { 1046 method->SetEntryPointFromQuickCompiledCodePtrSize(GetQuickToInterpreterBridge(), 1047 pointer_size); 1048 } 1049 } 1050 } 1051} 1052 1053void SanityCheckObjectsCallback(mirror::Object* obj, void* arg ATTRIBUTE_UNUSED) 1054 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1055 DCHECK(obj != nullptr); 1056 CHECK(obj->GetClass() != nullptr) << "Null class " << obj; 1057 CHECK(obj->GetClass()->GetClass() != nullptr) << "Null class class " << obj; 1058 if (obj->IsClass()) { 1059 auto klass = obj->AsClass(); 1060 ArtField* fields[2] = { klass->GetSFields(), klass->GetIFields() }; 1061 size_t num_fields[2] = { klass->NumStaticFields(), klass->NumInstanceFields() }; 1062 for (size_t i = 0; i < 2; ++i) { 1063 for (size_t j = 0; j < num_fields[i]; ++j) { 1064 CHECK_EQ(fields[i][j].GetDeclaringClass(), klass); 1065 } 1066 } 1067 } 1068} 1069 1070void ClassLinker::InitFromImage() { 1071 VLOG(startup) << "ClassLinker::InitFromImage entering"; 1072 CHECK(!init_done_); 1073 1074 Runtime* const runtime = Runtime::Current(); 1075 Thread* const self = Thread::Current(); 1076 gc::Heap* const heap = runtime->GetHeap(); 1077 gc::space::ImageSpace* const space = heap->GetImageSpace(); 1078 dex_cache_image_class_lookup_required_ = true; 1079 CHECK(space != nullptr); 1080 OatFile& oat_file = GetImageOatFile(space); 1081 CHECK_EQ(oat_file.GetOatHeader().GetImageFileLocationOatChecksum(), 0U); 1082 CHECK_EQ(oat_file.GetOatHeader().GetImageFileLocationOatDataBegin(), 0U); 1083 const char* image_file_location = oat_file.GetOatHeader(). 1084 GetStoreValueByKey(OatHeader::kImageLocationKey); 1085 CHECK(image_file_location == nullptr || *image_file_location == 0); 1086 quick_resolution_trampoline_ = oat_file.GetOatHeader().GetQuickResolutionTrampoline(); 1087 quick_imt_conflict_trampoline_ = oat_file.GetOatHeader().GetQuickImtConflictTrampoline(); 1088 quick_generic_jni_trampoline_ = oat_file.GetOatHeader().GetQuickGenericJniTrampoline(); 1089 quick_to_interpreter_bridge_trampoline_ = oat_file.GetOatHeader().GetQuickToInterpreterBridge(); 1090 mirror::Object* dex_caches_object = space->GetImageHeader().GetImageRoot(ImageHeader::kDexCaches); 1091 mirror::ObjectArray<mirror::DexCache>* dex_caches = 1092 dex_caches_object->AsObjectArray<mirror::DexCache>(); 1093 1094 StackHandleScope<1> hs(self); 1095 Handle<mirror::ObjectArray<mirror::Class>> class_roots(hs.NewHandle( 1096 space->GetImageHeader().GetImageRoot(ImageHeader::kClassRoots)-> 1097 AsObjectArray<mirror::Class>())); 1098 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class>>(class_roots.Get()); 1099 1100 // Special case of setting up the String class early so that we can test arbitrary objects 1101 // as being Strings or not 1102 mirror::String::SetClass(GetClassRoot(kJavaLangString)); 1103 1104 CHECK_EQ(oat_file.GetOatHeader().GetDexFileCount(), 1105 static_cast<uint32_t>(dex_caches->GetLength())); 1106 for (int32_t i = 0; i < dex_caches->GetLength(); i++) { 1107 StackHandleScope<1> hs2(self); 1108 Handle<mirror::DexCache> dex_cache(hs2.NewHandle(dex_caches->Get(i))); 1109 const std::string& dex_file_location(dex_cache->GetLocation()->ToModifiedUtf8()); 1110 const OatFile::OatDexFile* oat_dex_file = oat_file.GetOatDexFile(dex_file_location.c_str(), 1111 nullptr); 1112 CHECK(oat_dex_file != nullptr) << oat_file.GetLocation() << " " << dex_file_location; 1113 std::string error_msg; 1114 std::unique_ptr<const DexFile> dex_file = oat_dex_file->OpenDexFile(&error_msg); 1115 if (dex_file.get() == nullptr) { 1116 LOG(FATAL) << "Failed to open dex file " << dex_file_location 1117 << " from within oat file " << oat_file.GetLocation() 1118 << " error '" << error_msg << "'"; 1119 UNREACHABLE(); 1120 } 1121 1122 CHECK_EQ(dex_file->GetLocationChecksum(), oat_dex_file->GetDexFileLocationChecksum()); 1123 1124 AppendToBootClassPath(*dex_file.get(), dex_cache); 1125 opened_dex_files_.push_back(std::move(dex_file)); 1126 } 1127 1128 // Set classes on AbstractMethod early so that IsMethod tests can be performed during the live 1129 // bitmap walk. 1130 mirror::ArtMethod::SetClass(GetClassRoot(kJavaLangReflectArtMethod)); 1131 size_t art_method_object_size = mirror::ArtMethod::GetJavaLangReflectArtMethod()->GetObjectSize(); 1132 if (!runtime->IsAotCompiler()) { 1133 // Aot compiler supports having an image with a different pointer size than the runtime. This 1134 // happens on the host for compile 32 bit tests since we use a 64 bit libart compiler. We may 1135 // also use 32 bit dex2oat on a system with 64 bit apps. 1136 CHECK_EQ(art_method_object_size, mirror::ArtMethod::InstanceSize(sizeof(void*))) 1137 << sizeof(void*); 1138 } 1139 if (art_method_object_size == mirror::ArtMethod::InstanceSize(4)) { 1140 image_pointer_size_ = 4; 1141 } else { 1142 CHECK_EQ(art_method_object_size, mirror::ArtMethod::InstanceSize(8)); 1143 image_pointer_size_ = 8; 1144 } 1145 1146 // Set entry point to interpreter if in InterpretOnly mode. 1147 if (!runtime->IsAotCompiler() && runtime->GetInstrumentation()->InterpretOnly()) { 1148 heap->VisitObjects(InitFromImageInterpretOnlyCallback, this); 1149 } 1150 if (kSanityCheckObjects) { 1151 for (int32_t i = 0; i < dex_caches->GetLength(); i++) { 1152 auto* dex_cache = dex_caches->Get(i); 1153 for (size_t j = 0; j < dex_cache->NumResolvedFields(); ++j) { 1154 auto* field = dex_cache->GetResolvedField(j, image_pointer_size_); 1155 if (field != nullptr) { 1156 CHECK(field->GetDeclaringClass()->GetClass() != nullptr); 1157 } 1158 } 1159 } 1160 heap->VisitObjects(SanityCheckObjectsCallback, nullptr); 1161 } 1162 1163 // reinit class_roots_ 1164 mirror::Class::SetClassClass(class_roots->Get(kJavaLangClass)); 1165 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class>>(class_roots.Get()); 1166 1167 // reinit array_iftable_ from any array class instance, they should be == 1168 array_iftable_ = GcRoot<mirror::IfTable>(GetClassRoot(kObjectArrayClass)->GetIfTable()); 1169 DCHECK_EQ(array_iftable_.Read(), GetClassRoot(kBooleanArrayClass)->GetIfTable()); 1170 // String class root was set above 1171 mirror::Field::SetClass(GetClassRoot(kJavaLangReflectField)); 1172 mirror::Field::SetArrayClass(GetClassRoot(kJavaLangReflectFieldArrayClass)); 1173 mirror::Constructor::SetClass(GetClassRoot(kJavaLangReflectConstructor)); 1174 mirror::Constructor::SetArrayClass(GetClassRoot(kJavaLangReflectConstructorArrayClass)); 1175 mirror::Method::SetClass(GetClassRoot(kJavaLangReflectMethod)); 1176 mirror::Method::SetArrayClass(GetClassRoot(kJavaLangReflectMethodArrayClass)); 1177 mirror::Reference::SetClass(GetClassRoot(kJavaLangRefReference)); 1178 mirror::BooleanArray::SetArrayClass(GetClassRoot(kBooleanArrayClass)); 1179 mirror::ByteArray::SetArrayClass(GetClassRoot(kByteArrayClass)); 1180 mirror::CharArray::SetArrayClass(GetClassRoot(kCharArrayClass)); 1181 mirror::DoubleArray::SetArrayClass(GetClassRoot(kDoubleArrayClass)); 1182 mirror::FloatArray::SetArrayClass(GetClassRoot(kFloatArrayClass)); 1183 mirror::IntArray::SetArrayClass(GetClassRoot(kIntArrayClass)); 1184 mirror::LongArray::SetArrayClass(GetClassRoot(kLongArrayClass)); 1185 mirror::ShortArray::SetArrayClass(GetClassRoot(kShortArrayClass)); 1186 mirror::Throwable::SetClass(GetClassRoot(kJavaLangThrowable)); 1187 mirror::StackTraceElement::SetClass(GetClassRoot(kJavaLangStackTraceElement)); 1188 1189 FinishInit(self); 1190 1191 VLOG(startup) << "ClassLinker::InitFromImage exiting"; 1192} 1193 1194void ClassLinker::VisitClassRoots(RootVisitor* visitor, VisitRootFlags flags) { 1195 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 1196 BufferedRootVisitor<kDefaultBufferedRootCount> buffered_visitor( 1197 visitor, RootInfo(kRootStickyClass)); 1198 if ((flags & kVisitRootFlagAllRoots) != 0) { 1199 for (GcRoot<mirror::Class>& root : class_table_) { 1200 buffered_visitor.VisitRoot(root); 1201 root.Read()->VisitFieldRoots(buffered_visitor); 1202 } 1203 // PreZygote classes can't move so we won't need to update fields' declaring classes. 1204 for (GcRoot<mirror::Class>& root : pre_zygote_class_table_) { 1205 buffered_visitor.VisitRoot(root); 1206 root.Read()->VisitFieldRoots(buffered_visitor); 1207 } 1208 } else if ((flags & kVisitRootFlagNewRoots) != 0) { 1209 for (auto& root : new_class_roots_) { 1210 mirror::Class* old_ref = root.Read<kWithoutReadBarrier>(); 1211 old_ref->VisitFieldRoots(buffered_visitor); 1212 root.VisitRoot(visitor, RootInfo(kRootStickyClass)); 1213 mirror::Class* new_ref = root.Read<kWithoutReadBarrier>(); 1214 if (UNLIKELY(new_ref != old_ref)) { 1215 // Uh ohes, GC moved a root in the log. Need to search the class_table and update the 1216 // corresponding object. This is slow, but luckily for us, this may only happen with a 1217 // concurrent moving GC. 1218 auto it = class_table_.Find(GcRoot<mirror::Class>(old_ref)); 1219 DCHECK(it != class_table_.end()); 1220 *it = GcRoot<mirror::Class>(new_ref); 1221 } 1222 } 1223 } 1224 buffered_visitor.Flush(); // Flush before clearing new_class_roots_. 1225 if ((flags & kVisitRootFlagClearRootLog) != 0) { 1226 new_class_roots_.clear(); 1227 } 1228 if ((flags & kVisitRootFlagStartLoggingNewRoots) != 0) { 1229 log_new_class_table_roots_ = true; 1230 } else if ((flags & kVisitRootFlagStopLoggingNewRoots) != 0) { 1231 log_new_class_table_roots_ = false; 1232 } 1233 // We deliberately ignore the class roots in the image since we 1234 // handle image roots by using the MS/CMS rescanning of dirty cards. 1235} 1236 1237// Keep in sync with InitCallback. Anything we visit, we need to 1238// reinit references to when reinitializing a ClassLinker from a 1239// mapped image. 1240void ClassLinker::VisitRoots(RootVisitor* visitor, VisitRootFlags flags) { 1241 class_roots_.VisitRoot(visitor, RootInfo(kRootVMInternal)); 1242 Thread* const self = Thread::Current(); 1243 { 1244 ReaderMutexLock mu(self, dex_lock_); 1245 if ((flags & kVisitRootFlagAllRoots) != 0) { 1246 for (GcRoot<mirror::DexCache>& dex_cache : dex_caches_) { 1247 dex_cache.VisitRoot(visitor, RootInfo(kRootVMInternal)); 1248 } 1249 } else if ((flags & kVisitRootFlagNewRoots) != 0) { 1250 for (size_t index : new_dex_cache_roots_) { 1251 dex_caches_[index].VisitRoot(visitor, RootInfo(kRootVMInternal)); 1252 } 1253 } 1254 if ((flags & kVisitRootFlagClearRootLog) != 0) { 1255 new_dex_cache_roots_.clear(); 1256 } 1257 if ((flags & kVisitRootFlagStartLoggingNewRoots) != 0) { 1258 log_new_dex_caches_roots_ = true; 1259 } else if ((flags & kVisitRootFlagStopLoggingNewRoots) != 0) { 1260 log_new_dex_caches_roots_ = false; 1261 } 1262 } 1263 VisitClassRoots(visitor, flags); 1264 array_iftable_.VisitRoot(visitor, RootInfo(kRootVMInternal)); 1265 for (size_t i = 0; i < kFindArrayCacheSize; ++i) { 1266 find_array_class_cache_[i].VisitRootIfNonNull(visitor, RootInfo(kRootVMInternal)); 1267 } 1268} 1269 1270void ClassLinker::VisitClasses(ClassVisitor* visitor, void* arg) { 1271 if (dex_cache_image_class_lookup_required_) { 1272 MoveImageClassesToClassTable(); 1273 } 1274 // TODO: why isn't this a ReaderMutexLock? 1275 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 1276 for (GcRoot<mirror::Class>& root : class_table_) { 1277 if (!visitor(root.Read(), arg)) { 1278 return; 1279 } 1280 } 1281 for (GcRoot<mirror::Class>& root : pre_zygote_class_table_) { 1282 if (!visitor(root.Read(), arg)) { 1283 return; 1284 } 1285 } 1286} 1287 1288static bool GetClassesVisitorSet(mirror::Class* c, void* arg) { 1289 std::set<mirror::Class*>* classes = reinterpret_cast<std::set<mirror::Class*>*>(arg); 1290 classes->insert(c); 1291 return true; 1292} 1293 1294struct GetClassesVisitorArrayArg { 1295 Handle<mirror::ObjectArray<mirror::Class>>* classes; 1296 int32_t index; 1297 bool success; 1298}; 1299 1300static bool GetClassesVisitorArray(mirror::Class* c, void* varg) 1301 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1302 GetClassesVisitorArrayArg* arg = reinterpret_cast<GetClassesVisitorArrayArg*>(varg); 1303 if (arg->index < (*arg->classes)->GetLength()) { 1304 (*arg->classes)->Set(arg->index, c); 1305 arg->index++; 1306 return true; 1307 } else { 1308 arg->success = false; 1309 return false; 1310 } 1311} 1312 1313void ClassLinker::VisitClassesWithoutClassesLock(ClassVisitor* visitor, void* arg) { 1314 // TODO: it may be possible to avoid secondary storage if we iterate over dex caches. The problem 1315 // is avoiding duplicates. 1316 if (!kMovingClasses) { 1317 std::set<mirror::Class*> classes; 1318 VisitClasses(GetClassesVisitorSet, &classes); 1319 for (mirror::Class* klass : classes) { 1320 if (!visitor(klass, arg)) { 1321 return; 1322 } 1323 } 1324 } else { 1325 Thread* self = Thread::Current(); 1326 StackHandleScope<1> hs(self); 1327 MutableHandle<mirror::ObjectArray<mirror::Class>> classes = 1328 hs.NewHandle<mirror::ObjectArray<mirror::Class>>(nullptr); 1329 GetClassesVisitorArrayArg local_arg; 1330 local_arg.classes = &classes; 1331 local_arg.success = false; 1332 // We size the array assuming classes won't be added to the class table during the visit. 1333 // If this assumption fails we iterate again. 1334 while (!local_arg.success) { 1335 size_t class_table_size; 1336 { 1337 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 1338 class_table_size = class_table_.Size() + pre_zygote_class_table_.Size(); 1339 } 1340 mirror::Class* class_type = mirror::Class::GetJavaLangClass(); 1341 mirror::Class* array_of_class = FindArrayClass(self, &class_type); 1342 classes.Assign( 1343 mirror::ObjectArray<mirror::Class>::Alloc(self, array_of_class, class_table_size)); 1344 CHECK(classes.Get() != nullptr); // OOME. 1345 local_arg.index = 0; 1346 local_arg.success = true; 1347 VisitClasses(GetClassesVisitorArray, &local_arg); 1348 } 1349 for (int32_t i = 0; i < classes->GetLength(); ++i) { 1350 // If the class table shrank during creation of the clases array we expect null elements. If 1351 // the class table grew then the loop repeats. If classes are created after the loop has 1352 // finished then we don't visit. 1353 mirror::Class* klass = classes->Get(i); 1354 if (klass != nullptr && !visitor(klass, arg)) { 1355 return; 1356 } 1357 } 1358 } 1359} 1360 1361ClassLinker::~ClassLinker() { 1362 mirror::ArtMethod::ResetClass(); 1363 mirror::Class::ResetClass(); 1364 mirror::Constructor::ResetClass(); 1365 mirror::Field::ResetClass(); 1366 mirror::Method::ResetClass(); 1367 mirror::Reference::ResetClass(); 1368 mirror::StackTraceElement::ResetClass(); 1369 mirror::String::ResetClass(); 1370 mirror::Throwable::ResetClass(); 1371 mirror::BooleanArray::ResetArrayClass(); 1372 mirror::ByteArray::ResetArrayClass(); 1373 mirror::CharArray::ResetArrayClass(); 1374 mirror::Constructor::ResetArrayClass(); 1375 mirror::DoubleArray::ResetArrayClass(); 1376 mirror::Field::ResetArrayClass(); 1377 mirror::FloatArray::ResetArrayClass(); 1378 mirror::Method::ResetArrayClass(); 1379 mirror::IntArray::ResetArrayClass(); 1380 mirror::LongArray::ResetArrayClass(); 1381 mirror::ShortArray::ResetArrayClass(); 1382 STLDeleteElements(&oat_files_); 1383} 1384 1385mirror::DexCache* ClassLinker::AllocDexCache(Thread* self, const DexFile& dex_file) { 1386 gc::Heap* const heap = Runtime::Current()->GetHeap(); 1387 StackHandleScope<16> hs(self); 1388 Handle<mirror::Class> dex_cache_class(hs.NewHandle(GetClassRoot(kJavaLangDexCache))); 1389 Handle<mirror::DexCache> dex_cache( 1390 hs.NewHandle(down_cast<mirror::DexCache*>( 1391 heap->AllocObject<true>(self, dex_cache_class.Get(), dex_cache_class->GetObjectSize(), 1392 VoidFunctor())))); 1393 if (dex_cache.Get() == nullptr) { 1394 return nullptr; 1395 } 1396 Handle<mirror::String> 1397 location(hs.NewHandle(intern_table_->InternStrong(dex_file.GetLocation().c_str()))); 1398 if (location.Get() == nullptr) { 1399 return nullptr; 1400 } 1401 Handle<mirror::ObjectArray<mirror::String>> 1402 strings(hs.NewHandle(AllocStringArray(self, dex_file.NumStringIds()))); 1403 if (strings.Get() == nullptr) { 1404 return nullptr; 1405 } 1406 Handle<mirror::ObjectArray<mirror::Class>> 1407 types(hs.NewHandle(AllocClassArray(self, dex_file.NumTypeIds()))); 1408 if (types.Get() == nullptr) { 1409 return nullptr; 1410 } 1411 Handle<mirror::ObjectArray<mirror::ArtMethod>> 1412 methods(hs.NewHandle(AllocArtMethodArray(self, dex_file.NumMethodIds()))); 1413 if (methods.Get() == nullptr) { 1414 return nullptr; 1415 } 1416 Handle<mirror::Array> fields; 1417 if (image_pointer_size_ == 8) { 1418 fields = hs.NewHandle<mirror::Array>(mirror::LongArray::Alloc(self, dex_file.NumFieldIds())); 1419 } else { 1420 fields = hs.NewHandle<mirror::Array>(mirror::IntArray::Alloc(self, dex_file.NumFieldIds())); 1421 } 1422 if (fields.Get() == nullptr) { 1423 return nullptr; 1424 } 1425 dex_cache->Init(&dex_file, location.Get(), strings.Get(), types.Get(), methods.Get(), 1426 fields.Get()); 1427 return dex_cache.Get(); 1428} 1429 1430mirror::Class* ClassLinker::AllocClass(Thread* self, mirror::Class* java_lang_Class, 1431 uint32_t class_size) { 1432 DCHECK_GE(class_size, sizeof(mirror::Class)); 1433 gc::Heap* heap = Runtime::Current()->GetHeap(); 1434 mirror::Class::InitializeClassVisitor visitor(class_size); 1435 mirror::Object* k = kMovingClasses ? 1436 heap->AllocObject<true>(self, java_lang_Class, class_size, visitor) : 1437 heap->AllocNonMovableObject<true>(self, java_lang_Class, class_size, visitor); 1438 if (UNLIKELY(k == nullptr)) { 1439 CHECK(self->IsExceptionPending()); // OOME. 1440 return nullptr; 1441 } 1442 return k->AsClass(); 1443} 1444 1445mirror::Class* ClassLinker::AllocClass(Thread* self, uint32_t class_size) { 1446 return AllocClass(self, GetClassRoot(kJavaLangClass), class_size); 1447} 1448 1449mirror::ArtMethod* ClassLinker::AllocArtMethod(Thread* self) { 1450 return down_cast<mirror::ArtMethod*>( 1451 GetClassRoot(kJavaLangReflectArtMethod)->AllocNonMovableObject(self)); 1452} 1453 1454mirror::ObjectArray<mirror::StackTraceElement>* ClassLinker::AllocStackTraceElementArray( 1455 Thread* self, size_t length) { 1456 return mirror::ObjectArray<mirror::StackTraceElement>::Alloc( 1457 self, GetClassRoot(kJavaLangStackTraceElementArrayClass), length); 1458} 1459 1460mirror::Class* ClassLinker::EnsureResolved(Thread* self, const char* descriptor, 1461 mirror::Class* klass) { 1462 DCHECK(klass != nullptr); 1463 1464 // For temporary classes we must wait for them to be retired. 1465 if (init_done_ && klass->IsTemp()) { 1466 CHECK(!klass->IsResolved()); 1467 if (klass->IsErroneous()) { 1468 ThrowEarlierClassFailure(klass); 1469 return nullptr; 1470 } 1471 StackHandleScope<1> hs(self); 1472 Handle<mirror::Class> h_class(hs.NewHandle(klass)); 1473 ObjectLock<mirror::Class> lock(self, h_class); 1474 // Loop and wait for the resolving thread to retire this class. 1475 while (!h_class->IsRetired() && !h_class->IsErroneous()) { 1476 lock.WaitIgnoringInterrupts(); 1477 } 1478 if (h_class->IsErroneous()) { 1479 ThrowEarlierClassFailure(h_class.Get()); 1480 return nullptr; 1481 } 1482 CHECK(h_class->IsRetired()); 1483 // Get the updated class from class table. 1484 klass = LookupClass(self, descriptor, ComputeModifiedUtf8Hash(descriptor), 1485 h_class.Get()->GetClassLoader()); 1486 } 1487 1488 // Wait for the class if it has not already been linked. 1489 if (!klass->IsResolved() && !klass->IsErroneous()) { 1490 StackHandleScope<1> hs(self); 1491 HandleWrapper<mirror::Class> h_class(hs.NewHandleWrapper(&klass)); 1492 ObjectLock<mirror::Class> lock(self, h_class); 1493 // Check for circular dependencies between classes. 1494 if (!h_class->IsResolved() && h_class->GetClinitThreadId() == self->GetTid()) { 1495 ThrowClassCircularityError(h_class.Get()); 1496 mirror::Class::SetStatus(h_class, mirror::Class::kStatusError, self); 1497 return nullptr; 1498 } 1499 // Wait for the pending initialization to complete. 1500 while (!h_class->IsResolved() && !h_class->IsErroneous()) { 1501 lock.WaitIgnoringInterrupts(); 1502 } 1503 } 1504 1505 if (klass->IsErroneous()) { 1506 ThrowEarlierClassFailure(klass); 1507 return nullptr; 1508 } 1509 // Return the loaded class. No exceptions should be pending. 1510 CHECK(klass->IsResolved()) << PrettyClass(klass); 1511 self->AssertNoPendingException(); 1512 return klass; 1513} 1514 1515typedef std::pair<const DexFile*, const DexFile::ClassDef*> ClassPathEntry; 1516 1517// Search a collection of DexFiles for a descriptor 1518ClassPathEntry FindInClassPath(const char* descriptor, 1519 size_t hash, const std::vector<const DexFile*>& class_path) { 1520 for (const DexFile* dex_file : class_path) { 1521 const DexFile::ClassDef* dex_class_def = dex_file->FindClassDef(descriptor, hash); 1522 if (dex_class_def != nullptr) { 1523 return ClassPathEntry(dex_file, dex_class_def); 1524 } 1525 } 1526 return ClassPathEntry(nullptr, nullptr); 1527} 1528 1529static bool IsBootClassLoader(ScopedObjectAccessAlreadyRunnable& soa, 1530 mirror::ClassLoader* class_loader) 1531 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1532 return class_loader == nullptr || 1533 class_loader->GetClass() == 1534 soa.Decode<mirror::Class*>(WellKnownClasses::java_lang_BootClassLoader); 1535} 1536 1537bool ClassLinker::FindClassInPathClassLoader(ScopedObjectAccessAlreadyRunnable& soa, 1538 Thread* self, const char* descriptor, 1539 size_t hash, 1540 Handle<mirror::ClassLoader> class_loader, 1541 mirror::Class** result) { 1542 // Termination case: boot class-loader. 1543 if (IsBootClassLoader(soa, class_loader.Get())) { 1544 // The boot class loader, search the boot class path. 1545 ClassPathEntry pair = FindInClassPath(descriptor, hash, boot_class_path_); 1546 if (pair.second != nullptr) { 1547 mirror::Class* klass = LookupClass(self, descriptor, hash, nullptr); 1548 if (klass != nullptr) { 1549 *result = EnsureResolved(self, descriptor, klass); 1550 } else { 1551 *result = DefineClass(self, descriptor, hash, NullHandle<mirror::ClassLoader>(), 1552 *pair.first, *pair.second); 1553 } 1554 if (*result == nullptr) { 1555 CHECK(self->IsExceptionPending()) << descriptor; 1556 self->ClearException(); 1557 } 1558 } else { 1559 *result = nullptr; 1560 } 1561 return true; 1562 } 1563 1564 // Unsupported class-loader? 1565 if (class_loader->GetClass() != 1566 soa.Decode<mirror::Class*>(WellKnownClasses::dalvik_system_PathClassLoader)) { 1567 *result = nullptr; 1568 return false; 1569 } 1570 1571 // Handles as RegisterDexFile may allocate dex caches (and cause thread suspension). 1572 StackHandleScope<4> hs(self); 1573 Handle<mirror::ClassLoader> h_parent(hs.NewHandle(class_loader->GetParent())); 1574 bool recursive_result = FindClassInPathClassLoader(soa, self, descriptor, hash, h_parent, result); 1575 1576 if (!recursive_result) { 1577 // Something wrong up the chain. 1578 return false; 1579 } 1580 1581 if (*result != nullptr) { 1582 // Found the class up the chain. 1583 return true; 1584 } 1585 1586 // Handle this step. 1587 // Handle as if this is the child PathClassLoader. 1588 // The class loader is a PathClassLoader which inherits from BaseDexClassLoader. 1589 // We need to get the DexPathList and loop through it. 1590 ArtField* const cookie_field = soa.DecodeField(WellKnownClasses::dalvik_system_DexFile_cookie); 1591 ArtField* const dex_file_field = 1592 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList__Element_dexFile); 1593 mirror::Object* dex_path_list = 1594 soa.DecodeField(WellKnownClasses::dalvik_system_PathClassLoader_pathList)-> 1595 GetObject(class_loader.Get()); 1596 if (dex_path_list != nullptr && dex_file_field != nullptr && cookie_field != nullptr) { 1597 // DexPathList has an array dexElements of Elements[] which each contain a dex file. 1598 mirror::Object* dex_elements_obj = 1599 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList_dexElements)-> 1600 GetObject(dex_path_list); 1601 // Loop through each dalvik.system.DexPathList$Element's dalvik.system.DexFile and look 1602 // at the mCookie which is a DexFile vector. 1603 if (dex_elements_obj != nullptr) { 1604 Handle<mirror::ObjectArray<mirror::Object>> dex_elements = 1605 hs.NewHandle(dex_elements_obj->AsObjectArray<mirror::Object>()); 1606 for (int32_t i = 0; i < dex_elements->GetLength(); ++i) { 1607 mirror::Object* element = dex_elements->GetWithoutChecks(i); 1608 if (element == nullptr) { 1609 // Should never happen, fall back to java code to throw a NPE. 1610 break; 1611 } 1612 mirror::Object* dex_file = dex_file_field->GetObject(element); 1613 if (dex_file != nullptr) { 1614 mirror::LongArray* long_array = cookie_field->GetObject(dex_file)->AsLongArray(); 1615 if (long_array == nullptr) { 1616 // This should never happen so log a warning. 1617 LOG(WARNING) << "Null DexFile::mCookie for " << descriptor; 1618 break; 1619 } 1620 int32_t long_array_size = long_array->GetLength(); 1621 for (int32_t j = 0; j < long_array_size; ++j) { 1622 const DexFile* cp_dex_file = reinterpret_cast<const DexFile*>(static_cast<uintptr_t>( 1623 long_array->GetWithoutChecks(j))); 1624 const DexFile::ClassDef* dex_class_def = cp_dex_file->FindClassDef(descriptor, hash); 1625 if (dex_class_def != nullptr) { 1626 RegisterDexFile(*cp_dex_file); 1627 mirror::Class* klass = DefineClass(self, descriptor, hash, class_loader, 1628 *cp_dex_file, *dex_class_def); 1629 if (klass == nullptr) { 1630 CHECK(self->IsExceptionPending()) << descriptor; 1631 self->ClearException(); 1632 // TODO: Is it really right to break here, and not check the other dex files? 1633 return true; 1634 } 1635 *result = klass; 1636 return true; 1637 } 1638 } 1639 } 1640 } 1641 } 1642 self->AssertNoPendingException(); 1643 } 1644 1645 // Result is still null from the parent call, no need to set it again... 1646 return true; 1647} 1648 1649mirror::Class* ClassLinker::FindClass(Thread* self, const char* descriptor, 1650 Handle<mirror::ClassLoader> class_loader) { 1651 DCHECK_NE(*descriptor, '\0') << "descriptor is empty string"; 1652 DCHECK(self != nullptr); 1653 self->AssertNoPendingException(); 1654 if (descriptor[1] == '\0') { 1655 // only the descriptors of primitive types should be 1 character long, also avoid class lookup 1656 // for primitive classes that aren't backed by dex files. 1657 return FindPrimitiveClass(descriptor[0]); 1658 } 1659 const size_t hash = ComputeModifiedUtf8Hash(descriptor); 1660 // Find the class in the loaded classes table. 1661 mirror::Class* klass = LookupClass(self, descriptor, hash, class_loader.Get()); 1662 if (klass != nullptr) { 1663 return EnsureResolved(self, descriptor, klass); 1664 } 1665 // Class is not yet loaded. 1666 if (descriptor[0] == '[') { 1667 return CreateArrayClass(self, descriptor, hash, class_loader); 1668 } else if (class_loader.Get() == nullptr) { 1669 // The boot class loader, search the boot class path. 1670 ClassPathEntry pair = FindInClassPath(descriptor, hash, boot_class_path_); 1671 if (pair.second != nullptr) { 1672 return DefineClass(self, descriptor, hash, NullHandle<mirror::ClassLoader>(), *pair.first, 1673 *pair.second); 1674 } else { 1675 // The boot class loader is searched ahead of the application class loader, failures are 1676 // expected and will be wrapped in a ClassNotFoundException. Use the pre-allocated error to 1677 // trigger the chaining with a proper stack trace. 1678 mirror::Throwable* pre_allocated = Runtime::Current()->GetPreAllocatedNoClassDefFoundError(); 1679 self->SetException(pre_allocated); 1680 return nullptr; 1681 } 1682 } else { 1683 ScopedObjectAccessUnchecked soa(self); 1684 mirror::Class* cp_klass; 1685 if (FindClassInPathClassLoader(soa, self, descriptor, hash, class_loader, &cp_klass)) { 1686 // The chain was understood. So the value in cp_klass is either the class we were looking 1687 // for, or not found. 1688 if (cp_klass != nullptr) { 1689 return cp_klass; 1690 } 1691 // TODO: We handle the boot classpath loader in FindClassInPathClassLoader. Try to unify this 1692 // and the branch above. TODO: throw the right exception here. 1693 1694 // We'll let the Java-side rediscover all this and throw the exception with the right stack 1695 // trace. 1696 } 1697 1698 if (Runtime::Current()->IsAotCompiler()) { 1699 // Oops, compile-time, can't run actual class-loader code. 1700 mirror::Throwable* pre_allocated = Runtime::Current()->GetPreAllocatedNoClassDefFoundError(); 1701 self->SetException(pre_allocated); 1702 return nullptr; 1703 } 1704 1705 ScopedLocalRef<jobject> class_loader_object(soa.Env(), 1706 soa.AddLocalReference<jobject>(class_loader.Get())); 1707 std::string class_name_string(DescriptorToDot(descriptor)); 1708 ScopedLocalRef<jobject> result(soa.Env(), nullptr); 1709 { 1710 ScopedThreadStateChange tsc(self, kNative); 1711 ScopedLocalRef<jobject> class_name_object(soa.Env(), 1712 soa.Env()->NewStringUTF(class_name_string.c_str())); 1713 if (class_name_object.get() == nullptr) { 1714 DCHECK(self->IsExceptionPending()); // OOME. 1715 return nullptr; 1716 } 1717 CHECK(class_loader_object.get() != nullptr); 1718 result.reset(soa.Env()->CallObjectMethod(class_loader_object.get(), 1719 WellKnownClasses::java_lang_ClassLoader_loadClass, 1720 class_name_object.get())); 1721 } 1722 if (self->IsExceptionPending()) { 1723 // If the ClassLoader threw, pass that exception up. 1724 return nullptr; 1725 } else if (result.get() == nullptr) { 1726 // broken loader - throw NPE to be compatible with Dalvik 1727 ThrowNullPointerException(StringPrintf("ClassLoader.loadClass returned null for %s", 1728 class_name_string.c_str()).c_str()); 1729 return nullptr; 1730 } else { 1731 // success, return mirror::Class* 1732 return soa.Decode<mirror::Class*>(result.get()); 1733 } 1734 } 1735 UNREACHABLE(); 1736} 1737 1738mirror::Class* ClassLinker::DefineClass(Thread* self, const char* descriptor, size_t hash, 1739 Handle<mirror::ClassLoader> class_loader, 1740 const DexFile& dex_file, 1741 const DexFile::ClassDef& dex_class_def) { 1742 StackHandleScope<3> hs(self); 1743 auto klass = hs.NewHandle<mirror::Class>(nullptr); 1744 1745 // Load the class from the dex file. 1746 if (UNLIKELY(!init_done_)) { 1747 // finish up init of hand crafted class_roots_ 1748 if (strcmp(descriptor, "Ljava/lang/Object;") == 0) { 1749 klass.Assign(GetClassRoot(kJavaLangObject)); 1750 } else if (strcmp(descriptor, "Ljava/lang/Class;") == 0) { 1751 klass.Assign(GetClassRoot(kJavaLangClass)); 1752 } else if (strcmp(descriptor, "Ljava/lang/String;") == 0) { 1753 klass.Assign(GetClassRoot(kJavaLangString)); 1754 } else if (strcmp(descriptor, "Ljava/lang/ref/Reference;") == 0) { 1755 klass.Assign(GetClassRoot(kJavaLangRefReference)); 1756 } else if (strcmp(descriptor, "Ljava/lang/DexCache;") == 0) { 1757 klass.Assign(GetClassRoot(kJavaLangDexCache)); 1758 } else if (strcmp(descriptor, "Ljava/lang/reflect/ArtMethod;") == 0) { 1759 klass.Assign(GetClassRoot(kJavaLangReflectArtMethod)); 1760 } 1761 } 1762 1763 if (klass.Get() == nullptr) { 1764 // Allocate a class with the status of not ready. 1765 // Interface object should get the right size here. Regular class will 1766 // figure out the right size later and be replaced with one of the right 1767 // size when the class becomes resolved. 1768 klass.Assign(AllocClass(self, SizeOfClassWithoutEmbeddedTables(dex_file, dex_class_def))); 1769 } 1770 if (UNLIKELY(klass.Get() == nullptr)) { 1771 CHECK(self->IsExceptionPending()); // Expect an OOME. 1772 return nullptr; 1773 } 1774 klass->SetDexCache(FindDexCache(dex_file)); 1775 1776 SetupClass(dex_file, dex_class_def, klass, class_loader.Get()); 1777 1778 // Mark the string class by setting its access flag. 1779 if (UNLIKELY(!init_done_)) { 1780 if (strcmp(descriptor, "Ljava/lang/String;") == 0) { 1781 klass->SetStringClass(); 1782 } 1783 } 1784 1785 ObjectLock<mirror::Class> lock(self, klass); 1786 klass->SetClinitThreadId(self->GetTid()); 1787 1788 // Add the newly loaded class to the loaded classes table. 1789 mirror::Class* existing = InsertClass(descriptor, klass.Get(), hash); 1790 if (existing != nullptr) { 1791 // We failed to insert because we raced with another thread. Calling EnsureResolved may cause 1792 // this thread to block. 1793 return EnsureResolved(self, descriptor, existing); 1794 } 1795 1796 // Load the fields and other things after we are inserted in the table. This is so that we don't 1797 // end up allocating unfree-able linear alloc resources and then lose the race condition. The 1798 // other reason is that the field roots are only visited from the class table. So we need to be 1799 // inserted before we allocate / fill in these fields. 1800 LoadClass(self, dex_file, dex_class_def, klass); 1801 if (self->IsExceptionPending()) { 1802 // An exception occured during load, set status to erroneous while holding klass' lock in case 1803 // notification is necessary. 1804 if (!klass->IsErroneous()) { 1805 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 1806 } 1807 return nullptr; 1808 } 1809 1810 // Finish loading (if necessary) by finding parents 1811 CHECK(!klass->IsLoaded()); 1812 if (!LoadSuperAndInterfaces(klass, dex_file)) { 1813 // Loading failed. 1814 if (!klass->IsErroneous()) { 1815 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 1816 } 1817 return nullptr; 1818 } 1819 CHECK(klass->IsLoaded()); 1820 // Link the class (if necessary) 1821 CHECK(!klass->IsResolved()); 1822 // TODO: Use fast jobjects? 1823 auto interfaces = hs.NewHandle<mirror::ObjectArray<mirror::Class>>(nullptr); 1824 1825 mirror::Class* new_class = nullptr; 1826 if (!LinkClass(self, descriptor, klass, interfaces, &new_class)) { 1827 // Linking failed. 1828 if (!klass->IsErroneous()) { 1829 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 1830 } 1831 return nullptr; 1832 } 1833 self->AssertNoPendingException(); 1834 CHECK(new_class != nullptr) << descriptor; 1835 CHECK(new_class->IsResolved()) << descriptor; 1836 1837 Handle<mirror::Class> new_class_h(hs.NewHandle(new_class)); 1838 1839 // Instrumentation may have updated entrypoints for all methods of all 1840 // classes. However it could not update methods of this class while we 1841 // were loading it. Now the class is resolved, we can update entrypoints 1842 // as required by instrumentation. 1843 if (Runtime::Current()->GetInstrumentation()->AreExitStubsInstalled()) { 1844 // We must be in the kRunnable state to prevent instrumentation from 1845 // suspending all threads to update entrypoints while we are doing it 1846 // for this class. 1847 DCHECK_EQ(self->GetState(), kRunnable); 1848 Runtime::Current()->GetInstrumentation()->InstallStubsForClass(new_class_h.Get()); 1849 } 1850 1851 /* 1852 * We send CLASS_PREPARE events to the debugger from here. The 1853 * definition of "preparation" is creating the static fields for a 1854 * class and initializing them to the standard default values, but not 1855 * executing any code (that comes later, during "initialization"). 1856 * 1857 * We did the static preparation in LinkClass. 1858 * 1859 * The class has been prepared and resolved but possibly not yet verified 1860 * at this point. 1861 */ 1862 Dbg::PostClassPrepare(new_class_h.Get()); 1863 1864 return new_class_h.Get(); 1865} 1866 1867uint32_t ClassLinker::SizeOfClassWithoutEmbeddedTables(const DexFile& dex_file, 1868 const DexFile::ClassDef& dex_class_def) { 1869 const uint8_t* class_data = dex_file.GetClassData(dex_class_def); 1870 size_t num_ref = 0; 1871 size_t num_8 = 0; 1872 size_t num_16 = 0; 1873 size_t num_32 = 0; 1874 size_t num_64 = 0; 1875 if (class_data != nullptr) { 1876 for (ClassDataItemIterator it(dex_file, class_data); it.HasNextStaticField(); it.Next()) { 1877 const DexFile::FieldId& field_id = dex_file.GetFieldId(it.GetMemberIndex()); 1878 const char* descriptor = dex_file.GetFieldTypeDescriptor(field_id); 1879 char c = descriptor[0]; 1880 switch (c) { 1881 case 'L': 1882 case '[': 1883 num_ref++; 1884 break; 1885 case 'J': 1886 case 'D': 1887 num_64++; 1888 break; 1889 case 'I': 1890 case 'F': 1891 num_32++; 1892 break; 1893 case 'S': 1894 case 'C': 1895 num_16++; 1896 break; 1897 case 'B': 1898 case 'Z': 1899 num_8++; 1900 break; 1901 default: 1902 LOG(FATAL) << "Unknown descriptor: " << c; 1903 UNREACHABLE(); 1904 } 1905 } 1906 } 1907 return mirror::Class::ComputeClassSize(false, 0, num_8, num_16, num_32, num_64, num_ref); 1908} 1909 1910OatFile::OatClass ClassLinker::FindOatClass(const DexFile& dex_file, uint16_t class_def_idx, 1911 bool* found) { 1912 DCHECK_NE(class_def_idx, DexFile::kDexNoIndex16); 1913 const OatFile::OatDexFile* oat_dex_file = dex_file.GetOatDexFile(); 1914 if (oat_dex_file == nullptr) { 1915 *found = false; 1916 return OatFile::OatClass::Invalid(); 1917 } 1918 *found = true; 1919 return oat_dex_file->GetOatClass(class_def_idx); 1920} 1921 1922static uint32_t GetOatMethodIndexFromMethodIndex(const DexFile& dex_file, uint16_t class_def_idx, 1923 uint32_t method_idx) { 1924 const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_idx); 1925 const uint8_t* class_data = dex_file.GetClassData(class_def); 1926 CHECK(class_data != nullptr); 1927 ClassDataItemIterator it(dex_file, class_data); 1928 // Skip fields 1929 while (it.HasNextStaticField()) { 1930 it.Next(); 1931 } 1932 while (it.HasNextInstanceField()) { 1933 it.Next(); 1934 } 1935 // Process methods 1936 size_t class_def_method_index = 0; 1937 while (it.HasNextDirectMethod()) { 1938 if (it.GetMemberIndex() == method_idx) { 1939 return class_def_method_index; 1940 } 1941 class_def_method_index++; 1942 it.Next(); 1943 } 1944 while (it.HasNextVirtualMethod()) { 1945 if (it.GetMemberIndex() == method_idx) { 1946 return class_def_method_index; 1947 } 1948 class_def_method_index++; 1949 it.Next(); 1950 } 1951 DCHECK(!it.HasNext()); 1952 LOG(FATAL) << "Failed to find method index " << method_idx << " in " << dex_file.GetLocation(); 1953 UNREACHABLE(); 1954} 1955 1956const OatFile::OatMethod ClassLinker::FindOatMethodFor(mirror::ArtMethod* method, bool* found) { 1957 // Although we overwrite the trampoline of non-static methods, we may get here via the resolution 1958 // method for direct methods (or virtual methods made direct). 1959 mirror::Class* declaring_class = method->GetDeclaringClass(); 1960 size_t oat_method_index; 1961 if (method->IsStatic() || method->IsDirect()) { 1962 // Simple case where the oat method index was stashed at load time. 1963 oat_method_index = method->GetMethodIndex(); 1964 } else { 1965 // We're invoking a virtual method directly (thanks to sharpening), compute the oat_method_index 1966 // by search for its position in the declared virtual methods. 1967 oat_method_index = declaring_class->NumDirectMethods(); 1968 size_t end = declaring_class->NumVirtualMethods(); 1969 bool found_virtual = false; 1970 for (size_t i = 0; i < end; i++) { 1971 // Check method index instead of identity in case of duplicate method definitions. 1972 if (method->GetDexMethodIndex() == 1973 declaring_class->GetVirtualMethod(i)->GetDexMethodIndex()) { 1974 found_virtual = true; 1975 break; 1976 } 1977 oat_method_index++; 1978 } 1979 CHECK(found_virtual) << "Didn't find oat method index for virtual method: " 1980 << PrettyMethod(method); 1981 } 1982 DCHECK_EQ(oat_method_index, 1983 GetOatMethodIndexFromMethodIndex(*declaring_class->GetDexCache()->GetDexFile(), 1984 method->GetDeclaringClass()->GetDexClassDefIndex(), 1985 method->GetDexMethodIndex())); 1986 OatFile::OatClass oat_class = FindOatClass(*declaring_class->GetDexCache()->GetDexFile(), 1987 declaring_class->GetDexClassDefIndex(), 1988 found); 1989 if (!(*found)) { 1990 return OatFile::OatMethod::Invalid(); 1991 } 1992 return oat_class.GetOatMethod(oat_method_index); 1993} 1994 1995// Special case to get oat code without overwriting a trampoline. 1996const void* ClassLinker::GetQuickOatCodeFor(mirror::ArtMethod* method) { 1997 CHECK(!method->IsAbstract()) << PrettyMethod(method); 1998 if (method->IsProxyMethod()) { 1999 return GetQuickProxyInvokeHandler(); 2000 } 2001 bool found; 2002 OatFile::OatMethod oat_method = FindOatMethodFor(method, &found); 2003 if (found) { 2004 auto* code = oat_method.GetQuickCode(); 2005 if (code != nullptr) { 2006 return code; 2007 } 2008 } 2009 jit::Jit* const jit = Runtime::Current()->GetJit(); 2010 if (jit != nullptr) { 2011 auto* code = jit->GetCodeCache()->GetCodeFor(method); 2012 if (code != nullptr) { 2013 return code; 2014 } 2015 } 2016 if (method->IsNative()) { 2017 // No code and native? Use generic trampoline. 2018 return GetQuickGenericJniStub(); 2019 } 2020 return GetQuickToInterpreterBridge(); 2021} 2022 2023const void* ClassLinker::GetOatMethodQuickCodeFor(mirror::ArtMethod* method) { 2024 if (method->IsNative() || method->IsAbstract() || method->IsProxyMethod()) { 2025 return nullptr; 2026 } 2027 bool found; 2028 OatFile::OatMethod oat_method = FindOatMethodFor(method, &found); 2029 if (found) { 2030 return oat_method.GetQuickCode(); 2031 } 2032 jit::Jit* jit = Runtime::Current()->GetJit(); 2033 if (jit != nullptr) { 2034 auto* code = jit->GetCodeCache()->GetCodeFor(method); 2035 if (code != nullptr) { 2036 return code; 2037 } 2038 } 2039 return nullptr; 2040} 2041 2042const void* ClassLinker::GetQuickOatCodeFor(const DexFile& dex_file, uint16_t class_def_idx, 2043 uint32_t method_idx) { 2044 bool found; 2045 OatFile::OatClass oat_class = FindOatClass(dex_file, class_def_idx, &found); 2046 if (!found) { 2047 return nullptr; 2048 } 2049 uint32_t oat_method_idx = GetOatMethodIndexFromMethodIndex(dex_file, class_def_idx, method_idx); 2050 return oat_class.GetOatMethod(oat_method_idx).GetQuickCode(); 2051} 2052 2053// Returns true if the method must run with interpreter, false otherwise. 2054static bool NeedsInterpreter(mirror::ArtMethod* method, const void* quick_code) 2055 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 2056 if (quick_code == nullptr) { 2057 // No code: need interpreter. 2058 // May return true for native code, in the case of generic JNI 2059 // DCHECK(!method->IsNative()); 2060 return true; 2061 } 2062 // If interpreter mode is enabled, every method (except native and proxy) must 2063 // be run with interpreter. 2064 return Runtime::Current()->GetInstrumentation()->InterpretOnly() && 2065 !method->IsNative() && !method->IsProxyMethod(); 2066} 2067 2068void ClassLinker::FixupStaticTrampolines(mirror::Class* klass) { 2069 DCHECK(klass->IsInitialized()) << PrettyDescriptor(klass); 2070 if (klass->NumDirectMethods() == 0) { 2071 return; // No direct methods => no static methods. 2072 } 2073 Runtime* runtime = Runtime::Current(); 2074 if (!runtime->IsStarted()) { 2075 if (runtime->IsAotCompiler() || runtime->GetHeap()->HasImageSpace()) { 2076 return; // OAT file unavailable. 2077 } 2078 } 2079 2080 const DexFile& dex_file = klass->GetDexFile(); 2081 const DexFile::ClassDef* dex_class_def = klass->GetClassDef(); 2082 CHECK(dex_class_def != nullptr); 2083 const uint8_t* class_data = dex_file.GetClassData(*dex_class_def); 2084 // There should always be class data if there were direct methods. 2085 CHECK(class_data != nullptr) << PrettyDescriptor(klass); 2086 ClassDataItemIterator it(dex_file, class_data); 2087 // Skip fields 2088 while (it.HasNextStaticField()) { 2089 it.Next(); 2090 } 2091 while (it.HasNextInstanceField()) { 2092 it.Next(); 2093 } 2094 bool has_oat_class; 2095 OatFile::OatClass oat_class = FindOatClass(dex_file, klass->GetDexClassDefIndex(), 2096 &has_oat_class); 2097 // Link the code of methods skipped by LinkCode. 2098 for (size_t method_index = 0; it.HasNextDirectMethod(); ++method_index, it.Next()) { 2099 mirror::ArtMethod* method = klass->GetDirectMethod(method_index); 2100 if (!method->IsStatic()) { 2101 // Only update static methods. 2102 continue; 2103 } 2104 const void* quick_code = nullptr; 2105 if (has_oat_class) { 2106 OatFile::OatMethod oat_method = oat_class.GetOatMethod(method_index); 2107 quick_code = oat_method.GetQuickCode(); 2108 } 2109 const bool enter_interpreter = NeedsInterpreter(method, quick_code); 2110 if (enter_interpreter) { 2111 // Use interpreter entry point. 2112 // Check whether the method is native, in which case it's generic JNI. 2113 if (quick_code == nullptr && method->IsNative()) { 2114 quick_code = GetQuickGenericJniStub(); 2115 } else { 2116 quick_code = GetQuickToInterpreterBridge(); 2117 } 2118 } 2119 runtime->GetInstrumentation()->UpdateMethodsCode(method, quick_code); 2120 } 2121 // Ignore virtual methods on the iterator. 2122} 2123 2124void ClassLinker::LinkCode(Handle<mirror::ArtMethod> method, 2125 const OatFile::OatClass* oat_class, 2126 uint32_t class_def_method_index) { 2127 Runtime* runtime = Runtime::Current(); 2128 if (runtime->IsAotCompiler()) { 2129 // The following code only applies to a non-compiler runtime. 2130 return; 2131 } 2132 // Method shouldn't have already been linked. 2133 DCHECK(method->GetEntryPointFromQuickCompiledCode() == nullptr); 2134 if (oat_class != nullptr) { 2135 // Every kind of method should at least get an invoke stub from the oat_method. 2136 // non-abstract methods also get their code pointers. 2137 const OatFile::OatMethod oat_method = oat_class->GetOatMethod(class_def_method_index); 2138 oat_method.LinkMethod(method.Get()); 2139 } 2140 2141 // Install entry point from interpreter. 2142 bool enter_interpreter = NeedsInterpreter(method.Get(), 2143 method->GetEntryPointFromQuickCompiledCode()); 2144 if (enter_interpreter && !method->IsNative()) { 2145 method->SetEntryPointFromInterpreter(artInterpreterToInterpreterBridge); 2146 } else { 2147 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 2148 } 2149 2150 if (method->IsAbstract()) { 2151 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge()); 2152 return; 2153 } 2154 2155 if (method->IsStatic() && !method->IsConstructor()) { 2156 // For static methods excluding the class initializer, install the trampoline. 2157 // It will be replaced by the proper entry point by ClassLinker::FixupStaticTrampolines 2158 // after initializing class (see ClassLinker::InitializeClass method). 2159 method->SetEntryPointFromQuickCompiledCode(GetQuickResolutionStub()); 2160 } else if (enter_interpreter) { 2161 if (!method->IsNative()) { 2162 // Set entry point from compiled code if there's no code or in interpreter only mode. 2163 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge()); 2164 } else { 2165 method->SetEntryPointFromQuickCompiledCode(GetQuickGenericJniStub()); 2166 } 2167 } 2168 2169 if (method->IsNative()) { 2170 // Unregistering restores the dlsym lookup stub. 2171 method->UnregisterNative(); 2172 2173 if (enter_interpreter) { 2174 // We have a native method here without code. Then it should have either the generic JNI 2175 // trampoline as entrypoint (non-static), or the resolution trampoline (static). 2176 // TODO: this doesn't handle all the cases where trampolines may be installed. 2177 const void* entry_point = method->GetEntryPointFromQuickCompiledCode(); 2178 DCHECK(IsQuickGenericJniStub(entry_point) || IsQuickResolutionStub(entry_point)); 2179 } 2180 } 2181} 2182 2183void ClassLinker::SetupClass(const DexFile& dex_file, const DexFile::ClassDef& dex_class_def, 2184 Handle<mirror::Class> klass, mirror::ClassLoader* class_loader) { 2185 CHECK(klass.Get() != nullptr); 2186 CHECK(klass->GetDexCache() != nullptr); 2187 CHECK_EQ(mirror::Class::kStatusNotReady, klass->GetStatus()); 2188 const char* descriptor = dex_file.GetClassDescriptor(dex_class_def); 2189 CHECK(descriptor != nullptr); 2190 2191 klass->SetClass(GetClassRoot(kJavaLangClass)); 2192 uint32_t access_flags = dex_class_def.GetJavaAccessFlags(); 2193 CHECK_EQ(access_flags & ~kAccJavaFlagsMask, 0U); 2194 klass->SetAccessFlags(access_flags); 2195 klass->SetClassLoader(class_loader); 2196 DCHECK_EQ(klass->GetPrimitiveType(), Primitive::kPrimNot); 2197 mirror::Class::SetStatus(klass, mirror::Class::kStatusIdx, nullptr); 2198 2199 klass->SetDexClassDefIndex(dex_file.GetIndexForClassDef(dex_class_def)); 2200 klass->SetDexTypeIndex(dex_class_def.class_idx_); 2201 CHECK(klass->GetDexCacheStrings() != nullptr); 2202} 2203 2204void ClassLinker::LoadClass(Thread* self, const DexFile& dex_file, 2205 const DexFile::ClassDef& dex_class_def, 2206 Handle<mirror::Class> klass) { 2207 const uint8_t* class_data = dex_file.GetClassData(dex_class_def); 2208 if (class_data == nullptr) { 2209 return; // no fields or methods - for example a marker interface 2210 } 2211 bool has_oat_class = false; 2212 if (Runtime::Current()->IsStarted() && !Runtime::Current()->IsAotCompiler()) { 2213 OatFile::OatClass oat_class = FindOatClass(dex_file, klass->GetDexClassDefIndex(), 2214 &has_oat_class); 2215 if (has_oat_class) { 2216 LoadClassMembers(self, dex_file, class_data, klass, &oat_class); 2217 } 2218 } 2219 if (!has_oat_class) { 2220 LoadClassMembers(self, dex_file, class_data, klass, nullptr); 2221 } 2222} 2223 2224ArtField* ClassLinker::AllocArtFieldArray(Thread* self, size_t length) { 2225 auto* const la = Runtime::Current()->GetLinearAlloc(); 2226 auto* ptr = reinterpret_cast<ArtField*>(la->AllocArray<ArtField>(self, length)); 2227 CHECK(ptr!= nullptr); 2228 std::uninitialized_fill_n(ptr, length, ArtField()); 2229 return ptr; 2230} 2231 2232void ClassLinker::LoadClassMembers(Thread* self, const DexFile& dex_file, 2233 const uint8_t* class_data, 2234 Handle<mirror::Class> klass, 2235 const OatFile::OatClass* oat_class) { 2236 // Load static fields. 2237 ClassDataItemIterator it(dex_file, class_data); 2238 const size_t num_sfields = it.NumStaticFields(); 2239 ArtField* sfields = num_sfields != 0 ? AllocArtFieldArray(self, num_sfields) : nullptr; 2240 for (size_t i = 0; it.HasNextStaticField(); i++, it.Next()) { 2241 CHECK_LT(i, num_sfields); 2242 LoadField(it, klass, &sfields[i]); 2243 } 2244 klass->SetSFields(sfields); 2245 klass->SetNumStaticFields(num_sfields); 2246 DCHECK_EQ(klass->NumStaticFields(), num_sfields); 2247 // Load instance fields. 2248 const size_t num_ifields = it.NumInstanceFields(); 2249 ArtField* ifields = num_ifields != 0 ? AllocArtFieldArray(self, num_ifields) : nullptr; 2250 for (size_t i = 0; it.HasNextInstanceField(); i++, it.Next()) { 2251 CHECK_LT(i, num_ifields); 2252 LoadField(it, klass, &ifields[i]); 2253 } 2254 klass->SetIFields(ifields); 2255 klass->SetNumInstanceFields(num_ifields); 2256 DCHECK_EQ(klass->NumInstanceFields(), num_ifields); 2257 // Note: We cannot have thread suspension until the field arrays are setup or else 2258 // Class::VisitFieldRoots may miss some fields. 2259 self->AllowThreadSuspension(); 2260 // Load methods. 2261 if (it.NumDirectMethods() != 0) { 2262 // TODO: append direct methods to class object 2263 mirror::ObjectArray<mirror::ArtMethod>* directs = 2264 AllocArtMethodArray(self, it.NumDirectMethods()); 2265 if (UNLIKELY(directs == nullptr)) { 2266 CHECK(self->IsExceptionPending()); // OOME. 2267 return; 2268 } 2269 klass->SetDirectMethods(directs); 2270 } 2271 if (it.NumVirtualMethods() != 0) { 2272 // TODO: append direct methods to class object 2273 mirror::ObjectArray<mirror::ArtMethod>* virtuals = 2274 AllocArtMethodArray(self, it.NumVirtualMethods()); 2275 if (UNLIKELY(virtuals == nullptr)) { 2276 CHECK(self->IsExceptionPending()); // OOME. 2277 return; 2278 } 2279 klass->SetVirtualMethods(virtuals); 2280 } 2281 size_t class_def_method_index = 0; 2282 uint32_t last_dex_method_index = DexFile::kDexNoIndex; 2283 size_t last_class_def_method_index = 0; 2284 for (size_t i = 0; it.HasNextDirectMethod(); i++, it.Next()) { 2285 self->AllowThreadSuspension(); 2286 StackHandleScope<1> hs(self); 2287 Handle<mirror::ArtMethod> method(hs.NewHandle(LoadMethod(self, dex_file, it, klass))); 2288 if (UNLIKELY(method.Get() == nullptr)) { 2289 CHECK(self->IsExceptionPending()); // OOME. 2290 return; 2291 } 2292 klass->SetDirectMethod(i, method.Get()); 2293 LinkCode(method, oat_class, class_def_method_index); 2294 uint32_t it_method_index = it.GetMemberIndex(); 2295 if (last_dex_method_index == it_method_index) { 2296 // duplicate case 2297 method->SetMethodIndex(last_class_def_method_index); 2298 } else { 2299 method->SetMethodIndex(class_def_method_index); 2300 last_dex_method_index = it_method_index; 2301 last_class_def_method_index = class_def_method_index; 2302 } 2303 class_def_method_index++; 2304 } 2305 for (size_t i = 0; it.HasNextVirtualMethod(); i++, it.Next()) { 2306 self->AllowThreadSuspension(); 2307 StackHandleScope<1> hs(self); 2308 Handle<mirror::ArtMethod> method(hs.NewHandle(LoadMethod(self, dex_file, it, klass))); 2309 if (UNLIKELY(method.Get() == nullptr)) { 2310 CHECK(self->IsExceptionPending()); // OOME. 2311 return; 2312 } 2313 klass->SetVirtualMethod(i, method.Get()); 2314 DCHECK_EQ(class_def_method_index, it.NumDirectMethods() + i); 2315 LinkCode(method, oat_class, class_def_method_index); 2316 class_def_method_index++; 2317 } 2318 DCHECK(!it.HasNext()); 2319} 2320 2321void ClassLinker::LoadField(const ClassDataItemIterator& it, Handle<mirror::Class> klass, 2322 ArtField* dst) { 2323 const uint32_t field_idx = it.GetMemberIndex(); 2324 dst->SetDexFieldIndex(field_idx); 2325 dst->SetDeclaringClass(klass.Get()); 2326 dst->SetAccessFlags(it.GetFieldAccessFlags()); 2327} 2328 2329mirror::ArtMethod* ClassLinker::LoadMethod(Thread* self, const DexFile& dex_file, 2330 const ClassDataItemIterator& it, 2331 Handle<mirror::Class> klass) { 2332 uint32_t dex_method_idx = it.GetMemberIndex(); 2333 const DexFile::MethodId& method_id = dex_file.GetMethodId(dex_method_idx); 2334 const char* method_name = dex_file.StringDataByIdx(method_id.name_idx_); 2335 2336 mirror::ArtMethod* dst = AllocArtMethod(self); 2337 if (UNLIKELY(dst == nullptr)) { 2338 CHECK(self->IsExceptionPending()); // OOME. 2339 return nullptr; 2340 } 2341 DCHECK(dst->IsArtMethod()) << PrettyDescriptor(dst->GetClass()); 2342 2343 ScopedAssertNoThreadSuspension ants(self, "LoadMethod"); 2344 dst->SetDexMethodIndex(dex_method_idx); 2345 dst->SetDeclaringClass(klass.Get()); 2346 dst->SetCodeItemOffset(it.GetMethodCodeItemOffset()); 2347 2348 dst->SetDexCacheResolvedMethods(klass->GetDexCache()->GetResolvedMethods()); 2349 dst->SetDexCacheResolvedTypes(klass->GetDexCache()->GetResolvedTypes()); 2350 2351 uint32_t access_flags = it.GetMethodAccessFlags(); 2352 2353 if (UNLIKELY(strcmp("finalize", method_name) == 0)) { 2354 // Set finalizable flag on declaring class. 2355 if (strcmp("V", dex_file.GetShorty(method_id.proto_idx_)) == 0) { 2356 // Void return type. 2357 if (klass->GetClassLoader() != nullptr) { // All non-boot finalizer methods are flagged. 2358 klass->SetFinalizable(); 2359 } else { 2360 std::string temp; 2361 const char* klass_descriptor = klass->GetDescriptor(&temp); 2362 // The Enum class declares a "final" finalize() method to prevent subclasses from 2363 // introducing a finalizer. We don't want to set the finalizable flag for Enum or its 2364 // subclasses, so we exclude it here. 2365 // We also want to avoid setting the flag on Object, where we know that finalize() is 2366 // empty. 2367 if (strcmp(klass_descriptor, "Ljava/lang/Object;") != 0 && 2368 strcmp(klass_descriptor, "Ljava/lang/Enum;") != 0) { 2369 klass->SetFinalizable(); 2370 } 2371 } 2372 } 2373 } else if (method_name[0] == '<') { 2374 // Fix broken access flags for initializers. Bug 11157540. 2375 bool is_init = (strcmp("<init>", method_name) == 0); 2376 bool is_clinit = !is_init && (strcmp("<clinit>", method_name) == 0); 2377 if (UNLIKELY(!is_init && !is_clinit)) { 2378 LOG(WARNING) << "Unexpected '<' at start of method name " << method_name; 2379 } else { 2380 if (UNLIKELY((access_flags & kAccConstructor) == 0)) { 2381 LOG(WARNING) << method_name << " didn't have expected constructor access flag in class " 2382 << PrettyDescriptor(klass.Get()) << " in dex file " << dex_file.GetLocation(); 2383 access_flags |= kAccConstructor; 2384 } 2385 } 2386 } 2387 dst->SetAccessFlags(access_flags); 2388 2389 return dst; 2390} 2391 2392void ClassLinker::AppendToBootClassPath(Thread* self, const DexFile& dex_file) { 2393 StackHandleScope<1> hs(self); 2394 Handle<mirror::DexCache> dex_cache(hs.NewHandle(AllocDexCache(self, dex_file))); 2395 CHECK(dex_cache.Get() != nullptr) << "Failed to allocate dex cache for " 2396 << dex_file.GetLocation(); 2397 AppendToBootClassPath(dex_file, dex_cache); 2398} 2399 2400void ClassLinker::AppendToBootClassPath(const DexFile& dex_file, 2401 Handle<mirror::DexCache> dex_cache) { 2402 CHECK(dex_cache.Get() != nullptr) << dex_file.GetLocation(); 2403 boot_class_path_.push_back(&dex_file); 2404 RegisterDexFile(dex_file, dex_cache); 2405} 2406 2407bool ClassLinker::IsDexFileRegisteredLocked(const DexFile& dex_file) { 2408 dex_lock_.AssertSharedHeld(Thread::Current()); 2409 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2410 mirror::DexCache* dex_cache = GetDexCache(i); 2411 if (dex_cache->GetDexFile() == &dex_file) { 2412 return true; 2413 } 2414 } 2415 return false; 2416} 2417 2418bool ClassLinker::IsDexFileRegistered(const DexFile& dex_file) { 2419 ReaderMutexLock mu(Thread::Current(), dex_lock_); 2420 return IsDexFileRegisteredLocked(dex_file); 2421} 2422 2423void ClassLinker::RegisterDexFileLocked(const DexFile& dex_file, 2424 Handle<mirror::DexCache> dex_cache) { 2425 dex_lock_.AssertExclusiveHeld(Thread::Current()); 2426 CHECK(dex_cache.Get() != nullptr) << dex_file.GetLocation(); 2427 CHECK(dex_cache->GetLocation()->Equals(dex_file.GetLocation())) 2428 << dex_cache->GetLocation()->ToModifiedUtf8() << " " << dex_file.GetLocation(); 2429 dex_caches_.push_back(GcRoot<mirror::DexCache>(dex_cache.Get())); 2430 dex_cache->SetDexFile(&dex_file); 2431 if (log_new_dex_caches_roots_) { 2432 // TODO: This is not safe if we can remove dex caches. 2433 new_dex_cache_roots_.push_back(dex_caches_.size() - 1); 2434 } 2435} 2436 2437void ClassLinker::RegisterDexFile(const DexFile& dex_file) { 2438 Thread* self = Thread::Current(); 2439 { 2440 ReaderMutexLock mu(self, dex_lock_); 2441 if (IsDexFileRegisteredLocked(dex_file)) { 2442 return; 2443 } 2444 } 2445 // Don't alloc while holding the lock, since allocation may need to 2446 // suspend all threads and another thread may need the dex_lock_ to 2447 // get to a suspend point. 2448 StackHandleScope<1> hs(self); 2449 Handle<mirror::DexCache> dex_cache(hs.NewHandle(AllocDexCache(self, dex_file))); 2450 CHECK(dex_cache.Get() != nullptr) << "Failed to allocate dex cache for " 2451 << dex_file.GetLocation(); 2452 { 2453 WriterMutexLock mu(self, dex_lock_); 2454 if (IsDexFileRegisteredLocked(dex_file)) { 2455 return; 2456 } 2457 RegisterDexFileLocked(dex_file, dex_cache); 2458 } 2459} 2460 2461void ClassLinker::RegisterDexFile(const DexFile& dex_file, 2462 Handle<mirror::DexCache> dex_cache) { 2463 WriterMutexLock mu(Thread::Current(), dex_lock_); 2464 RegisterDexFileLocked(dex_file, dex_cache); 2465} 2466 2467mirror::DexCache* ClassLinker::FindDexCache(const DexFile& dex_file) { 2468 ReaderMutexLock mu(Thread::Current(), dex_lock_); 2469 // Search assuming unique-ness of dex file. 2470 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2471 mirror::DexCache* dex_cache = GetDexCache(i); 2472 if (dex_cache->GetDexFile() == &dex_file) { 2473 return dex_cache; 2474 } 2475 } 2476 // Search matching by location name. 2477 std::string location(dex_file.GetLocation()); 2478 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2479 mirror::DexCache* dex_cache = GetDexCache(i); 2480 if (dex_cache->GetDexFile()->GetLocation() == location) { 2481 return dex_cache; 2482 } 2483 } 2484 // Failure, dump diagnostic and abort. 2485 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2486 mirror::DexCache* dex_cache = GetDexCache(i); 2487 LOG(ERROR) << "Registered dex file " << i << " = " << dex_cache->GetDexFile()->GetLocation(); 2488 } 2489 LOG(FATAL) << "Failed to find DexCache for DexFile " << location; 2490 UNREACHABLE(); 2491} 2492 2493void ClassLinker::FixupDexCaches(mirror::ArtMethod* resolution_method) { 2494 ReaderMutexLock mu(Thread::Current(), dex_lock_); 2495 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2496 mirror::DexCache* dex_cache = GetDexCache(i); 2497 dex_cache->Fixup(resolution_method); 2498 } 2499} 2500 2501mirror::Class* ClassLinker::CreatePrimitiveClass(Thread* self, Primitive::Type type) { 2502 mirror::Class* klass = AllocClass(self, mirror::Class::PrimitiveClassSize()); 2503 if (UNLIKELY(klass == nullptr)) { 2504 return nullptr; 2505 } 2506 return InitializePrimitiveClass(klass, type); 2507} 2508 2509mirror::Class* ClassLinker::InitializePrimitiveClass(mirror::Class* primitive_class, 2510 Primitive::Type type) { 2511 CHECK(primitive_class != nullptr); 2512 // Must hold lock on object when initializing. 2513 Thread* self = Thread::Current(); 2514 StackHandleScope<1> hs(self); 2515 Handle<mirror::Class> h_class(hs.NewHandle(primitive_class)); 2516 ObjectLock<mirror::Class> lock(self, h_class); 2517 h_class->SetAccessFlags(kAccPublic | kAccFinal | kAccAbstract); 2518 h_class->SetPrimitiveType(type); 2519 mirror::Class::SetStatus(h_class, mirror::Class::kStatusInitialized, self); 2520 const char* descriptor = Primitive::Descriptor(type); 2521 mirror::Class* existing = InsertClass(descriptor, h_class.Get(), 2522 ComputeModifiedUtf8Hash(descriptor)); 2523 CHECK(existing == nullptr) << "InitPrimitiveClass(" << type << ") failed"; 2524 return h_class.Get(); 2525} 2526 2527// Create an array class (i.e. the class object for the array, not the 2528// array itself). "descriptor" looks like "[C" or "[[[[B" or 2529// "[Ljava/lang/String;". 2530// 2531// If "descriptor" refers to an array of primitives, look up the 2532// primitive type's internally-generated class object. 2533// 2534// "class_loader" is the class loader of the class that's referring to 2535// us. It's used to ensure that we're looking for the element type in 2536// the right context. It does NOT become the class loader for the 2537// array class; that always comes from the base element class. 2538// 2539// Returns null with an exception raised on failure. 2540mirror::Class* ClassLinker::CreateArrayClass(Thread* self, const char* descriptor, size_t hash, 2541 Handle<mirror::ClassLoader> class_loader) { 2542 // Identify the underlying component type 2543 CHECK_EQ('[', descriptor[0]); 2544 StackHandleScope<2> hs(self); 2545 MutableHandle<mirror::Class> component_type(hs.NewHandle(FindClass(self, descriptor + 1, 2546 class_loader))); 2547 if (component_type.Get() == nullptr) { 2548 DCHECK(self->IsExceptionPending()); 2549 // We need to accept erroneous classes as component types. 2550 const size_t component_hash = ComputeModifiedUtf8Hash(descriptor + 1); 2551 component_type.Assign(LookupClass(self, descriptor + 1, component_hash, class_loader.Get())); 2552 if (component_type.Get() == nullptr) { 2553 DCHECK(self->IsExceptionPending()); 2554 return nullptr; 2555 } else { 2556 self->ClearException(); 2557 } 2558 } 2559 if (UNLIKELY(component_type->IsPrimitiveVoid())) { 2560 ThrowNoClassDefFoundError("Attempt to create array of void primitive type"); 2561 return nullptr; 2562 } 2563 // See if the component type is already loaded. Array classes are 2564 // always associated with the class loader of their underlying 2565 // element type -- an array of Strings goes with the loader for 2566 // java/lang/String -- so we need to look for it there. (The 2567 // caller should have checked for the existence of the class 2568 // before calling here, but they did so with *their* class loader, 2569 // not the component type's loader.) 2570 // 2571 // If we find it, the caller adds "loader" to the class' initiating 2572 // loader list, which should prevent us from going through this again. 2573 // 2574 // This call is unnecessary if "loader" and "component_type->GetClassLoader()" 2575 // are the same, because our caller (FindClass) just did the 2576 // lookup. (Even if we get this wrong we still have correct behavior, 2577 // because we effectively do this lookup again when we add the new 2578 // class to the hash table --- necessary because of possible races with 2579 // other threads.) 2580 if (class_loader.Get() != component_type->GetClassLoader()) { 2581 mirror::Class* new_class = LookupClass(self, descriptor, hash, component_type->GetClassLoader()); 2582 if (new_class != nullptr) { 2583 return new_class; 2584 } 2585 } 2586 2587 // Fill out the fields in the Class. 2588 // 2589 // It is possible to execute some methods against arrays, because 2590 // all arrays are subclasses of java_lang_Object_, so we need to set 2591 // up a vtable. We can just point at the one in java_lang_Object_. 2592 // 2593 // Array classes are simple enough that we don't need to do a full 2594 // link step. 2595 auto new_class = hs.NewHandle<mirror::Class>(nullptr); 2596 if (UNLIKELY(!init_done_)) { 2597 // Classes that were hand created, ie not by FindSystemClass 2598 if (strcmp(descriptor, "[Ljava/lang/Class;") == 0) { 2599 new_class.Assign(GetClassRoot(kClassArrayClass)); 2600 } else if (strcmp(descriptor, "[Ljava/lang/Object;") == 0) { 2601 new_class.Assign(GetClassRoot(kObjectArrayClass)); 2602 } else if (strcmp(descriptor, GetClassRootDescriptor(kJavaLangStringArrayClass)) == 0) { 2603 new_class.Assign(GetClassRoot(kJavaLangStringArrayClass)); 2604 } else if (strcmp(descriptor, 2605 GetClassRootDescriptor(kJavaLangReflectArtMethodArrayClass)) == 0) { 2606 new_class.Assign(GetClassRoot(kJavaLangReflectArtMethodArrayClass)); 2607 } else if (strcmp(descriptor, "[C") == 0) { 2608 new_class.Assign(GetClassRoot(kCharArrayClass)); 2609 } else if (strcmp(descriptor, "[I") == 0) { 2610 new_class.Assign(GetClassRoot(kIntArrayClass)); 2611 } else if (strcmp(descriptor, "[J") == 0) { 2612 new_class.Assign(GetClassRoot(kLongArrayClass)); 2613 } 2614 } 2615 if (new_class.Get() == nullptr) { 2616 new_class.Assign(AllocClass(self, mirror::Array::ClassSize())); 2617 if (new_class.Get() == nullptr) { 2618 return nullptr; 2619 } 2620 new_class->SetComponentType(component_type.Get()); 2621 } 2622 ObjectLock<mirror::Class> lock(self, new_class); // Must hold lock on object when initializing. 2623 DCHECK(new_class->GetComponentType() != nullptr); 2624 mirror::Class* java_lang_Object = GetClassRoot(kJavaLangObject); 2625 new_class->SetSuperClass(java_lang_Object); 2626 new_class->SetVTable(java_lang_Object->GetVTable()); 2627 new_class->SetPrimitiveType(Primitive::kPrimNot); 2628 new_class->SetClassLoader(component_type->GetClassLoader()); 2629 mirror::Class::SetStatus(new_class, mirror::Class::kStatusLoaded, self); 2630 { 2631 StackHandleScope<mirror::Class::kImtSize> hs2(self, 2632 Runtime::Current()->GetImtUnimplementedMethod()); 2633 new_class->PopulateEmbeddedImtAndVTable(&hs2); 2634 } 2635 mirror::Class::SetStatus(new_class, mirror::Class::kStatusInitialized, self); 2636 // don't need to set new_class->SetObjectSize(..) 2637 // because Object::SizeOf delegates to Array::SizeOf 2638 2639 2640 // All arrays have java/lang/Cloneable and java/io/Serializable as 2641 // interfaces. We need to set that up here, so that stuff like 2642 // "instanceof" works right. 2643 // 2644 // Note: The GC could run during the call to FindSystemClass, 2645 // so we need to make sure the class object is GC-valid while we're in 2646 // there. Do this by clearing the interface list so the GC will just 2647 // think that the entries are null. 2648 2649 2650 // Use the single, global copies of "interfaces" and "iftable" 2651 // (remember not to free them for arrays). 2652 { 2653 mirror::IfTable* array_iftable = array_iftable_.Read(); 2654 CHECK(array_iftable != nullptr); 2655 new_class->SetIfTable(array_iftable); 2656 } 2657 2658 // Inherit access flags from the component type. 2659 int access_flags = new_class->GetComponentType()->GetAccessFlags(); 2660 // Lose any implementation detail flags; in particular, arrays aren't finalizable. 2661 access_flags &= kAccJavaFlagsMask; 2662 // Arrays can't be used as a superclass or interface, so we want to add "abstract final" 2663 // and remove "interface". 2664 access_flags |= kAccAbstract | kAccFinal; 2665 access_flags &= ~kAccInterface; 2666 2667 new_class->SetAccessFlags(access_flags); 2668 2669 mirror::Class* existing = InsertClass(descriptor, new_class.Get(), hash); 2670 if (existing == nullptr) { 2671 return new_class.Get(); 2672 } 2673 // Another thread must have loaded the class after we 2674 // started but before we finished. Abandon what we've 2675 // done. 2676 // 2677 // (Yes, this happens.) 2678 2679 return existing; 2680} 2681 2682mirror::Class* ClassLinker::FindPrimitiveClass(char type) { 2683 switch (type) { 2684 case 'B': 2685 return GetClassRoot(kPrimitiveByte); 2686 case 'C': 2687 return GetClassRoot(kPrimitiveChar); 2688 case 'D': 2689 return GetClassRoot(kPrimitiveDouble); 2690 case 'F': 2691 return GetClassRoot(kPrimitiveFloat); 2692 case 'I': 2693 return GetClassRoot(kPrimitiveInt); 2694 case 'J': 2695 return GetClassRoot(kPrimitiveLong); 2696 case 'S': 2697 return GetClassRoot(kPrimitiveShort); 2698 case 'Z': 2699 return GetClassRoot(kPrimitiveBoolean); 2700 case 'V': 2701 return GetClassRoot(kPrimitiveVoid); 2702 default: 2703 break; 2704 } 2705 std::string printable_type(PrintableChar(type)); 2706 ThrowNoClassDefFoundError("Not a primitive type: %s", printable_type.c_str()); 2707 return nullptr; 2708} 2709 2710mirror::Class* ClassLinker::InsertClass(const char* descriptor, mirror::Class* klass, 2711 size_t hash) { 2712 if (VLOG_IS_ON(class_linker)) { 2713 mirror::DexCache* dex_cache = klass->GetDexCache(); 2714 std::string source; 2715 if (dex_cache != nullptr) { 2716 source += " from "; 2717 source += dex_cache->GetLocation()->ToModifiedUtf8(); 2718 } 2719 LOG(INFO) << "Loaded class " << descriptor << source; 2720 } 2721 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2722 mirror::Class* existing = LookupClassFromTableLocked(descriptor, klass->GetClassLoader(), hash); 2723 if (existing != nullptr) { 2724 return existing; 2725 } 2726 if (kIsDebugBuild && !klass->IsTemp() && klass->GetClassLoader() == nullptr && 2727 dex_cache_image_class_lookup_required_) { 2728 // Check a class loaded with the system class loader matches one in the image if the class 2729 // is in the image. 2730 existing = LookupClassFromImage(descriptor); 2731 if (existing != nullptr) { 2732 CHECK_EQ(klass, existing); 2733 } 2734 } 2735 VerifyObject(klass); 2736 class_table_.InsertWithHash(GcRoot<mirror::Class>(klass), hash); 2737 if (log_new_class_table_roots_) { 2738 new_class_roots_.push_back(GcRoot<mirror::Class>(klass)); 2739 } 2740 return nullptr; 2741} 2742 2743mirror::Class* ClassLinker::UpdateClass(const char* descriptor, mirror::Class* klass, 2744 size_t hash) { 2745 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2746 auto existing_it = class_table_.FindWithHash(std::make_pair(descriptor, klass->GetClassLoader()), 2747 hash); 2748 if (existing_it == class_table_.end()) { 2749 CHECK(klass->IsProxyClass()); 2750 return nullptr; 2751 } 2752 2753 mirror::Class* existing = existing_it->Read(); 2754 CHECK_NE(existing, klass) << descriptor; 2755 CHECK(!existing->IsResolved()) << descriptor; 2756 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusResolving) << descriptor; 2757 2758 CHECK(!klass->IsTemp()) << descriptor; 2759 if (kIsDebugBuild && klass->GetClassLoader() == nullptr && 2760 dex_cache_image_class_lookup_required_) { 2761 // Check a class loaded with the system class loader matches one in the image if the class 2762 // is in the image. 2763 existing = LookupClassFromImage(descriptor); 2764 if (existing != nullptr) { 2765 CHECK_EQ(klass, existing) << descriptor; 2766 } 2767 } 2768 VerifyObject(klass); 2769 2770 // Update the element in the hash set. 2771 *existing_it = GcRoot<mirror::Class>(klass); 2772 if (log_new_class_table_roots_) { 2773 new_class_roots_.push_back(GcRoot<mirror::Class>(klass)); 2774 } 2775 2776 return existing; 2777} 2778 2779bool ClassLinker::RemoveClass(const char* descriptor, mirror::ClassLoader* class_loader) { 2780 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2781 auto pair = std::make_pair(descriptor, class_loader); 2782 auto it = class_table_.Find(pair); 2783 if (it != class_table_.end()) { 2784 class_table_.Erase(it); 2785 return true; 2786 } 2787 it = pre_zygote_class_table_.Find(pair); 2788 if (it != pre_zygote_class_table_.end()) { 2789 pre_zygote_class_table_.Erase(it); 2790 return true; 2791 } 2792 return false; 2793} 2794 2795mirror::Class* ClassLinker::LookupClass(Thread* self, const char* descriptor, size_t hash, 2796 mirror::ClassLoader* class_loader) { 2797 { 2798 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 2799 mirror::Class* result = LookupClassFromTableLocked(descriptor, class_loader, hash); 2800 if (result != nullptr) { 2801 return result; 2802 } 2803 } 2804 if (class_loader != nullptr || !dex_cache_image_class_lookup_required_) { 2805 return nullptr; 2806 } else { 2807 // Lookup failed but need to search dex_caches_. 2808 mirror::Class* result = LookupClassFromImage(descriptor); 2809 if (result != nullptr) { 2810 InsertClass(descriptor, result, hash); 2811 } else { 2812 // Searching the image dex files/caches failed, we don't want to get into this situation 2813 // often as map searches are faster, so after kMaxFailedDexCacheLookups move all image 2814 // classes into the class table. 2815 constexpr uint32_t kMaxFailedDexCacheLookups = 1000; 2816 if (++failed_dex_cache_class_lookups_ > kMaxFailedDexCacheLookups) { 2817 MoveImageClassesToClassTable(); 2818 } 2819 } 2820 return result; 2821 } 2822} 2823 2824mirror::Class* ClassLinker::LookupClassFromTableLocked(const char* descriptor, 2825 mirror::ClassLoader* class_loader, 2826 size_t hash) { 2827 auto descriptor_pair = std::make_pair(descriptor, class_loader); 2828 auto it = pre_zygote_class_table_.FindWithHash(descriptor_pair, hash); 2829 if (it == pre_zygote_class_table_.end()) { 2830 it = class_table_.FindWithHash(descriptor_pair, hash); 2831 if (it == class_table_.end()) { 2832 return nullptr; 2833 } 2834 } 2835 return it->Read(); 2836} 2837 2838static mirror::ObjectArray<mirror::DexCache>* GetImageDexCaches() 2839 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 2840 gc::space::ImageSpace* image = Runtime::Current()->GetHeap()->GetImageSpace(); 2841 CHECK(image != nullptr); 2842 mirror::Object* root = image->GetImageHeader().GetImageRoot(ImageHeader::kDexCaches); 2843 return root->AsObjectArray<mirror::DexCache>(); 2844} 2845 2846void ClassLinker::MoveImageClassesToClassTable() { 2847 Thread* self = Thread::Current(); 2848 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_); 2849 if (!dex_cache_image_class_lookup_required_) { 2850 return; // All dex cache classes are already in the class table. 2851 } 2852 ScopedAssertNoThreadSuspension ants(self, "Moving image classes to class table"); 2853 mirror::ObjectArray<mirror::DexCache>* dex_caches = GetImageDexCaches(); 2854 std::string temp; 2855 for (int32_t i = 0; i < dex_caches->GetLength(); i++) { 2856 mirror::DexCache* dex_cache = dex_caches->Get(i); 2857 mirror::ObjectArray<mirror::Class>* types = dex_cache->GetResolvedTypes(); 2858 for (int32_t j = 0; j < types->GetLength(); j++) { 2859 mirror::Class* klass = types->Get(j); 2860 if (klass != nullptr) { 2861 DCHECK(klass->GetClassLoader() == nullptr); 2862 const char* descriptor = klass->GetDescriptor(&temp); 2863 size_t hash = ComputeModifiedUtf8Hash(descriptor); 2864 mirror::Class* existing = LookupClassFromTableLocked(descriptor, nullptr, hash); 2865 if (existing != nullptr) { 2866 CHECK_EQ(existing, klass) << PrettyClassAndClassLoader(existing) << " != " 2867 << PrettyClassAndClassLoader(klass); 2868 } else { 2869 class_table_.Insert(GcRoot<mirror::Class>(klass)); 2870 if (log_new_class_table_roots_) { 2871 new_class_roots_.push_back(GcRoot<mirror::Class>(klass)); 2872 } 2873 } 2874 } 2875 } 2876 } 2877 dex_cache_image_class_lookup_required_ = false; 2878} 2879 2880void ClassLinker::MoveClassTableToPreZygote() { 2881 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2882 DCHECK(pre_zygote_class_table_.Empty()); 2883 pre_zygote_class_table_ = std::move(class_table_); 2884 class_table_.Clear(); 2885} 2886 2887mirror::Class* ClassLinker::LookupClassFromImage(const char* descriptor) { 2888 ScopedAssertNoThreadSuspension ants(Thread::Current(), "Image class lookup"); 2889 mirror::ObjectArray<mirror::DexCache>* dex_caches = GetImageDexCaches(); 2890 for (int32_t i = 0; i < dex_caches->GetLength(); ++i) { 2891 mirror::DexCache* dex_cache = dex_caches->Get(i); 2892 const DexFile* dex_file = dex_cache->GetDexFile(); 2893 // Try binary searching the string/type index. 2894 const DexFile::StringId* string_id = dex_file->FindStringId(descriptor); 2895 if (string_id != nullptr) { 2896 const DexFile::TypeId* type_id = 2897 dex_file->FindTypeId(dex_file->GetIndexForStringId(*string_id)); 2898 if (type_id != nullptr) { 2899 uint16_t type_idx = dex_file->GetIndexForTypeId(*type_id); 2900 mirror::Class* klass = dex_cache->GetResolvedType(type_idx); 2901 if (klass != nullptr) { 2902 return klass; 2903 } 2904 } 2905 } 2906 } 2907 return nullptr; 2908} 2909 2910void ClassLinker::LookupClasses(const char* descriptor, std::vector<mirror::Class*>& result) { 2911 result.clear(); 2912 if (dex_cache_image_class_lookup_required_) { 2913 MoveImageClassesToClassTable(); 2914 } 2915 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2916 while (true) { 2917 auto it = class_table_.Find(descriptor); 2918 if (it == class_table_.end()) { 2919 break; 2920 } 2921 result.push_back(it->Read()); 2922 class_table_.Erase(it); 2923 } 2924 for (mirror::Class* k : result) { 2925 class_table_.Insert(GcRoot<mirror::Class>(k)); 2926 } 2927 size_t pre_zygote_start = result.size(); 2928 // Now handle the pre zygote table. 2929 // Note: This dirties the pre-zygote table but shouldn't be an issue since LookupClasses is only 2930 // called from the debugger. 2931 while (true) { 2932 auto it = pre_zygote_class_table_.Find(descriptor); 2933 if (it == pre_zygote_class_table_.end()) { 2934 break; 2935 } 2936 result.push_back(it->Read()); 2937 pre_zygote_class_table_.Erase(it); 2938 } 2939 for (size_t i = pre_zygote_start; i < result.size(); ++i) { 2940 pre_zygote_class_table_.Insert(GcRoot<mirror::Class>(result[i])); 2941 } 2942} 2943 2944void ClassLinker::VerifyClass(Thread* self, Handle<mirror::Class> klass) { 2945 // TODO: assert that the monitor on the Class is held 2946 ObjectLock<mirror::Class> lock(self, klass); 2947 2948 // Don't attempt to re-verify if already sufficiently verified. 2949 if (klass->IsVerified()) { 2950 EnsurePreverifiedMethods(klass); 2951 return; 2952 } 2953 if (klass->IsCompileTimeVerified() && Runtime::Current()->IsAotCompiler()) { 2954 return; 2955 } 2956 2957 // The class might already be erroneous, for example at compile time if we attempted to verify 2958 // this class as a parent to another. 2959 if (klass->IsErroneous()) { 2960 ThrowEarlierClassFailure(klass.Get()); 2961 return; 2962 } 2963 2964 if (klass->GetStatus() == mirror::Class::kStatusResolved) { 2965 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerifying, self); 2966 } else { 2967 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime) 2968 << PrettyClass(klass.Get()); 2969 CHECK(!Runtime::Current()->IsAotCompiler()); 2970 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerifyingAtRuntime, self); 2971 } 2972 2973 // Skip verification if disabled. 2974 if (!Runtime::Current()->IsVerificationEnabled()) { 2975 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self); 2976 EnsurePreverifiedMethods(klass); 2977 return; 2978 } 2979 2980 // Verify super class. 2981 StackHandleScope<2> hs(self); 2982 Handle<mirror::Class> super(hs.NewHandle(klass->GetSuperClass())); 2983 if (super.Get() != nullptr) { 2984 // Acquire lock to prevent races on verifying the super class. 2985 ObjectLock<mirror::Class> super_lock(self, super); 2986 2987 if (!super->IsVerified() && !super->IsErroneous()) { 2988 VerifyClass(self, super); 2989 } 2990 if (!super->IsCompileTimeVerified()) { 2991 std::string error_msg( 2992 StringPrintf("Rejecting class %s that attempts to sub-class erroneous class %s", 2993 PrettyDescriptor(klass.Get()).c_str(), 2994 PrettyDescriptor(super.Get()).c_str())); 2995 LOG(WARNING) << error_msg << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8(); 2996 Handle<mirror::Throwable> cause(hs.NewHandle(self->GetException())); 2997 if (cause.Get() != nullptr) { 2998 self->ClearException(); 2999 } 3000 ThrowVerifyError(klass.Get(), "%s", error_msg.c_str()); 3001 if (cause.Get() != nullptr) { 3002 self->GetException()->SetCause(cause.Get()); 3003 } 3004 ClassReference ref(klass->GetDexCache()->GetDexFile(), klass->GetDexClassDefIndex()); 3005 if (Runtime::Current()->IsAotCompiler()) { 3006 Runtime::Current()->GetCompilerCallbacks()->ClassRejected(ref); 3007 } 3008 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3009 return; 3010 } 3011 } 3012 3013 // Try to use verification information from the oat file, otherwise do runtime verification. 3014 const DexFile& dex_file = *klass->GetDexCache()->GetDexFile(); 3015 mirror::Class::Status oat_file_class_status(mirror::Class::kStatusNotReady); 3016 bool preverified = VerifyClassUsingOatFile(dex_file, klass.Get(), oat_file_class_status); 3017 if (oat_file_class_status == mirror::Class::kStatusError) { 3018 VLOG(class_linker) << "Skipping runtime verification of erroneous class " 3019 << PrettyDescriptor(klass.Get()) << " in " 3020 << klass->GetDexCache()->GetLocation()->ToModifiedUtf8(); 3021 ThrowVerifyError(klass.Get(), "Rejecting class %s because it failed compile-time verification", 3022 PrettyDescriptor(klass.Get()).c_str()); 3023 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3024 return; 3025 } 3026 verifier::MethodVerifier::FailureKind verifier_failure = verifier::MethodVerifier::kNoFailure; 3027 std::string error_msg; 3028 if (!preverified) { 3029 verifier_failure = verifier::MethodVerifier::VerifyClass(self, klass.Get(), 3030 Runtime::Current()->IsAotCompiler(), 3031 &error_msg); 3032 } 3033 if (preverified || verifier_failure != verifier::MethodVerifier::kHardFailure) { 3034 if (!preverified && verifier_failure != verifier::MethodVerifier::kNoFailure) { 3035 VLOG(class_linker) << "Soft verification failure in class " << PrettyDescriptor(klass.Get()) 3036 << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8() 3037 << " because: " << error_msg; 3038 } 3039 self->AssertNoPendingException(); 3040 // Make sure all classes referenced by catch blocks are resolved. 3041 ResolveClassExceptionHandlerTypes(dex_file, klass); 3042 if (verifier_failure == verifier::MethodVerifier::kNoFailure) { 3043 // Even though there were no verifier failures we need to respect whether the super-class 3044 // was verified or requiring runtime reverification. 3045 if (super.Get() == nullptr || super->IsVerified()) { 3046 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self); 3047 } else { 3048 CHECK_EQ(super->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime); 3049 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetryVerificationAtRuntime, self); 3050 // Pretend a soft failure occured so that we don't consider the class verified below. 3051 verifier_failure = verifier::MethodVerifier::kSoftFailure; 3052 } 3053 } else { 3054 CHECK_EQ(verifier_failure, verifier::MethodVerifier::kSoftFailure); 3055 // Soft failures at compile time should be retried at runtime. Soft 3056 // failures at runtime will be handled by slow paths in the generated 3057 // code. Set status accordingly. 3058 if (Runtime::Current()->IsAotCompiler()) { 3059 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetryVerificationAtRuntime, self); 3060 } else { 3061 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self); 3062 // As this is a fake verified status, make sure the methods are _not_ marked preverified 3063 // later. 3064 klass->SetPreverified(); 3065 } 3066 } 3067 } else { 3068 LOG(WARNING) << "Verification failed on class " << PrettyDescriptor(klass.Get()) 3069 << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8() 3070 << " because: " << error_msg; 3071 self->AssertNoPendingException(); 3072 ThrowVerifyError(klass.Get(), "%s", error_msg.c_str()); 3073 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3074 } 3075 if (preverified || verifier_failure == verifier::MethodVerifier::kNoFailure) { 3076 // Class is verified so we don't need to do any access check on its methods. 3077 // Let the interpreter know it by setting the kAccPreverified flag onto each 3078 // method. 3079 // Note: we're going here during compilation and at runtime. When we set the 3080 // kAccPreverified flag when compiling image classes, the flag is recorded 3081 // in the image and is set when loading the image. 3082 EnsurePreverifiedMethods(klass); 3083 } 3084} 3085 3086void ClassLinker::EnsurePreverifiedMethods(Handle<mirror::Class> klass) { 3087 if (!klass->IsPreverified()) { 3088 klass->SetPreverifiedFlagOnAllMethods(); 3089 klass->SetPreverified(); 3090 } 3091} 3092 3093bool ClassLinker::VerifyClassUsingOatFile(const DexFile& dex_file, mirror::Class* klass, 3094 mirror::Class::Status& oat_file_class_status) { 3095 // If we're compiling, we can only verify the class using the oat file if 3096 // we are not compiling the image or if the class we're verifying is not part of 3097 // the app. In other words, we will only check for preverification of bootclasspath 3098 // classes. 3099 if (Runtime::Current()->IsAotCompiler()) { 3100 // Are we compiling the bootclasspath? 3101 if (Runtime::Current()->GetCompilerCallbacks()->IsBootImage()) { 3102 return false; 3103 } 3104 // We are compiling an app (not the image). 3105 3106 // Is this an app class? (I.e. not a bootclasspath class) 3107 if (klass->GetClassLoader() != nullptr) { 3108 return false; 3109 } 3110 } 3111 3112 const OatFile::OatDexFile* oat_dex_file = dex_file.GetOatDexFile(); 3113 // In case we run without an image there won't be a backing oat file. 3114 if (oat_dex_file == nullptr) { 3115 return false; 3116 } 3117 3118 // We may be running with a preopted oat file but without image. In this case, 3119 // we don't skip verification of preverified classes to ensure we initialize 3120 // dex caches with all types resolved during verification. 3121 // We need to trust image classes, as these might be coming out of a pre-opted, quickened boot 3122 // image (that we just failed loading), and the verifier can't be run on quickened opcodes when 3123 // the runtime isn't started. On the other hand, app classes can be re-verified even if they are 3124 // already pre-opted, as then the runtime is started. 3125 if (!Runtime::Current()->IsAotCompiler() && 3126 !Runtime::Current()->GetHeap()->HasImageSpace() && 3127 klass->GetClassLoader() != nullptr) { 3128 return false; 3129 } 3130 3131 uint16_t class_def_index = klass->GetDexClassDefIndex(); 3132 oat_file_class_status = oat_dex_file->GetOatClass(class_def_index).GetStatus(); 3133 if (oat_file_class_status == mirror::Class::kStatusVerified || 3134 oat_file_class_status == mirror::Class::kStatusInitialized) { 3135 return true; 3136 } 3137 if (oat_file_class_status == mirror::Class::kStatusRetryVerificationAtRuntime) { 3138 // Compile time verification failed with a soft error. Compile time verification can fail 3139 // because we have incomplete type information. Consider the following: 3140 // class ... { 3141 // Foo x; 3142 // .... () { 3143 // if (...) { 3144 // v1 gets assigned a type of resolved class Foo 3145 // } else { 3146 // v1 gets assigned a type of unresolved class Bar 3147 // } 3148 // iput x = v1 3149 // } } 3150 // when we merge v1 following the if-the-else it results in Conflict 3151 // (see verifier::RegType::Merge) as we can't know the type of Bar and we could possibly be 3152 // allowing an unsafe assignment to the field x in the iput (javac may have compiled this as 3153 // it knew Bar was a sub-class of Foo, but for us this may have been moved into a separate apk 3154 // at compile time). 3155 return false; 3156 } 3157 if (oat_file_class_status == mirror::Class::kStatusError) { 3158 // Compile time verification failed with a hard error. This is caused by invalid instructions 3159 // in the class. These errors are unrecoverable. 3160 return false; 3161 } 3162 if (oat_file_class_status == mirror::Class::kStatusNotReady) { 3163 // Status is uninitialized if we couldn't determine the status at compile time, for example, 3164 // not loading the class. 3165 // TODO: when the verifier doesn't rely on Class-es failing to resolve/load the type hierarchy 3166 // isn't a problem and this case shouldn't occur 3167 return false; 3168 } 3169 std::string temp; 3170 LOG(FATAL) << "Unexpected class status: " << oat_file_class_status 3171 << " " << dex_file.GetLocation() << " " << PrettyClass(klass) << " " 3172 << klass->GetDescriptor(&temp); 3173 UNREACHABLE(); 3174} 3175 3176void ClassLinker::ResolveClassExceptionHandlerTypes(const DexFile& dex_file, 3177 Handle<mirror::Class> klass) { 3178 for (size_t i = 0; i < klass->NumDirectMethods(); i++) { 3179 ResolveMethodExceptionHandlerTypes(dex_file, klass->GetDirectMethod(i)); 3180 } 3181 for (size_t i = 0; i < klass->NumVirtualMethods(); i++) { 3182 ResolveMethodExceptionHandlerTypes(dex_file, klass->GetVirtualMethod(i)); 3183 } 3184} 3185 3186void ClassLinker::ResolveMethodExceptionHandlerTypes(const DexFile& dex_file, 3187 mirror::ArtMethod* method) { 3188 // similar to DexVerifier::ScanTryCatchBlocks and dex2oat's ResolveExceptionsForMethod. 3189 const DexFile::CodeItem* code_item = dex_file.GetCodeItem(method->GetCodeItemOffset()); 3190 if (code_item == nullptr) { 3191 return; // native or abstract method 3192 } 3193 if (code_item->tries_size_ == 0) { 3194 return; // nothing to process 3195 } 3196 const uint8_t* handlers_ptr = DexFile::GetCatchHandlerData(*code_item, 0); 3197 uint32_t handlers_size = DecodeUnsignedLeb128(&handlers_ptr); 3198 ClassLinker* linker = Runtime::Current()->GetClassLinker(); 3199 for (uint32_t idx = 0; idx < handlers_size; idx++) { 3200 CatchHandlerIterator iterator(handlers_ptr); 3201 for (; iterator.HasNext(); iterator.Next()) { 3202 // Ensure exception types are resolved so that they don't need resolution to be delivered, 3203 // unresolved exception types will be ignored by exception delivery 3204 if (iterator.GetHandlerTypeIndex() != DexFile::kDexNoIndex16) { 3205 mirror::Class* exception_type = linker->ResolveType(iterator.GetHandlerTypeIndex(), method); 3206 if (exception_type == nullptr) { 3207 DCHECK(Thread::Current()->IsExceptionPending()); 3208 Thread::Current()->ClearException(); 3209 } 3210 } 3211 } 3212 handlers_ptr = iterator.EndDataPointer(); 3213 } 3214} 3215 3216static void CheckProxyConstructor(mirror::ArtMethod* constructor); 3217static void CheckProxyMethod(Handle<mirror::ArtMethod> method, 3218 Handle<mirror::ArtMethod> prototype); 3219 3220mirror::Class* ClassLinker::CreateProxyClass(ScopedObjectAccessAlreadyRunnable& soa, jstring name, 3221 jobjectArray interfaces, jobject loader, 3222 jobjectArray methods, jobjectArray throws) { 3223 Thread* self = soa.Self(); 3224 StackHandleScope<9> hs(self); 3225 MutableHandle<mirror::Class> klass(hs.NewHandle( 3226 AllocClass(self, GetClassRoot(kJavaLangClass), sizeof(mirror::Class)))); 3227 if (klass.Get() == nullptr) { 3228 CHECK(self->IsExceptionPending()); // OOME. 3229 return nullptr; 3230 } 3231 DCHECK(klass->GetClass() != nullptr); 3232 klass->SetObjectSize(sizeof(mirror::Proxy)); 3233 // Set the class access flags incl. preverified, so we do not try to set the flag on the methods. 3234 klass->SetAccessFlags(kAccClassIsProxy | kAccPublic | kAccFinal | kAccPreverified); 3235 klass->SetClassLoader(soa.Decode<mirror::ClassLoader*>(loader)); 3236 DCHECK_EQ(klass->GetPrimitiveType(), Primitive::kPrimNot); 3237 klass->SetName(soa.Decode<mirror::String*>(name)); 3238 mirror::Class* proxy_class = GetClassRoot(kJavaLangReflectProxy); 3239 klass->SetDexCache(proxy_class->GetDexCache()); 3240 mirror::Class::SetStatus(klass, mirror::Class::kStatusIdx, self); 3241 3242 // Instance fields are inherited, but we add a couple of static fields... 3243 const size_t num_fields = 2; 3244 ArtField* sfields = AllocArtFieldArray(self, num_fields); 3245 klass->SetSFields(sfields); 3246 klass->SetNumStaticFields(num_fields); 3247 3248 // 1. Create a static field 'interfaces' that holds the _declared_ interfaces implemented by 3249 // our proxy, so Class.getInterfaces doesn't return the flattened set. 3250 ArtField* interfaces_sfield = &sfields[0]; 3251 interfaces_sfield->SetDexFieldIndex(0); 3252 interfaces_sfield->SetDeclaringClass(klass.Get()); 3253 interfaces_sfield->SetAccessFlags(kAccStatic | kAccPublic | kAccFinal); 3254 3255 // 2. Create a static field 'throws' that holds exceptions thrown by our methods. 3256 ArtField* throws_sfield = &sfields[1]; 3257 throws_sfield->SetDexFieldIndex(1); 3258 throws_sfield->SetDeclaringClass(klass.Get()); 3259 throws_sfield->SetAccessFlags(kAccStatic | kAccPublic | kAccFinal); 3260 3261 // Proxies have 1 direct method, the constructor 3262 { 3263 mirror::ObjectArray<mirror::ArtMethod>* directs = AllocArtMethodArray(self, 1); 3264 if (UNLIKELY(directs == nullptr)) { 3265 CHECK(self->IsExceptionPending()); // OOME. 3266 return nullptr; 3267 } 3268 klass->SetDirectMethods(directs); 3269 mirror::ArtMethod* constructor = CreateProxyConstructor(self, klass, proxy_class); 3270 if (UNLIKELY(constructor == nullptr)) { 3271 CHECK(self->IsExceptionPending()); // OOME. 3272 return nullptr; 3273 } 3274 klass->SetDirectMethod(0, constructor); 3275 } 3276 3277 // Create virtual method using specified prototypes. 3278 auto h_methods = hs.NewHandle(soa.Decode<mirror::ObjectArray<mirror::Method>*>(methods)); 3279 DCHECK_EQ(h_methods->GetClass(), mirror::Method::ArrayClass()) 3280 << PrettyClass(h_methods->GetClass()); 3281 const size_t num_virtual_methods = h_methods->GetLength(); 3282 { 3283 mirror::ObjectArray<mirror::ArtMethod>* virtuals = AllocArtMethodArray(self, 3284 num_virtual_methods); 3285 if (UNLIKELY(virtuals == nullptr)) { 3286 CHECK(self->IsExceptionPending()); // OOME. 3287 return nullptr; 3288 } 3289 klass->SetVirtualMethods(virtuals); 3290 } 3291 for (size_t i = 0; i < num_virtual_methods; ++i) { 3292 StackHandleScope<1> hs2(self); 3293 Handle<mirror::ArtMethod> prototype(hs2.NewHandle(h_methods->Get(i)->GetArtMethod())); 3294 mirror::ArtMethod* clone = CreateProxyMethod(self, klass, prototype); 3295 if (UNLIKELY(clone == nullptr)) { 3296 CHECK(self->IsExceptionPending()); // OOME. 3297 return nullptr; 3298 } 3299 klass->SetVirtualMethod(i, clone); 3300 } 3301 3302 klass->SetSuperClass(proxy_class); // The super class is java.lang.reflect.Proxy 3303 mirror::Class::SetStatus(klass, mirror::Class::kStatusLoaded, self); // Now effectively in the loaded state. 3304 self->AssertNoPendingException(); 3305 3306 std::string descriptor(GetDescriptorForProxy(klass.Get())); 3307 mirror::Class* new_class = nullptr; 3308 { 3309 // Must hold lock on object when resolved. 3310 ObjectLock<mirror::Class> resolution_lock(self, klass); 3311 // Link the fields and virtual methods, creating vtable and iftables 3312 Handle<mirror::ObjectArray<mirror::Class> > h_interfaces( 3313 hs.NewHandle(soa.Decode<mirror::ObjectArray<mirror::Class>*>(interfaces))); 3314 if (!LinkClass(self, descriptor.c_str(), klass, h_interfaces, &new_class)) { 3315 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3316 return nullptr; 3317 } 3318 } 3319 3320 CHECK(klass->IsRetired()); 3321 CHECK_NE(klass.Get(), new_class); 3322 klass.Assign(new_class); 3323 3324 CHECK_EQ(interfaces_sfield->GetDeclaringClass(), new_class); 3325 interfaces_sfield->SetObject<false>(klass.Get(), 3326 soa.Decode<mirror::ObjectArray<mirror::Class>*>(interfaces)); 3327 CHECK_EQ(throws_sfield->GetDeclaringClass(), new_class); 3328 throws_sfield->SetObject<false>(klass.Get(), 3329 soa.Decode<mirror::ObjectArray<mirror::ObjectArray<mirror::Class> >*>(throws)); 3330 3331 { 3332 // Lock on klass is released. Lock new class object. 3333 ObjectLock<mirror::Class> initialization_lock(self, klass); 3334 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitialized, self); 3335 } 3336 3337 // sanity checks 3338 if (kIsDebugBuild) { 3339 CHECK(klass->GetIFields() == nullptr); 3340 CheckProxyConstructor(klass->GetDirectMethod(0)); 3341 for (size_t i = 0; i < num_virtual_methods; ++i) { 3342 StackHandleScope<2> hs2(self); 3343 Handle<mirror::ArtMethod> prototype(hs2.NewHandle(h_methods->Get(i)->GetArtMethod())); 3344 Handle<mirror::ArtMethod> virtual_method(hs2.NewHandle(klass->GetVirtualMethod(i))); 3345 CheckProxyMethod(virtual_method, prototype); 3346 } 3347 3348 mirror::String* decoded_name = soa.Decode<mirror::String*>(name); 3349 std::string interfaces_field_name(StringPrintf("java.lang.Class[] %s.interfaces", 3350 decoded_name->ToModifiedUtf8().c_str())); 3351 CHECK_EQ(PrettyField(klass->GetStaticField(0)), interfaces_field_name); 3352 3353 std::string throws_field_name(StringPrintf("java.lang.Class[][] %s.throws", 3354 decoded_name->ToModifiedUtf8().c_str())); 3355 CHECK_EQ(PrettyField(klass->GetStaticField(1)), throws_field_name); 3356 3357 CHECK_EQ(klass.Get()->GetInterfaces(), 3358 soa.Decode<mirror::ObjectArray<mirror::Class>*>(interfaces)); 3359 CHECK_EQ(klass.Get()->GetThrows(), 3360 soa.Decode<mirror::ObjectArray<mirror::ObjectArray<mirror::Class>>*>(throws)); 3361 } 3362 mirror::Class* existing = InsertClass(descriptor.c_str(), klass.Get(), 3363 ComputeModifiedUtf8Hash(descriptor.c_str())); 3364 CHECK(existing == nullptr); 3365 return klass.Get(); 3366} 3367 3368std::string ClassLinker::GetDescriptorForProxy(mirror::Class* proxy_class) { 3369 DCHECK(proxy_class->IsProxyClass()); 3370 mirror::String* name = proxy_class->GetName(); 3371 DCHECK(name != nullptr); 3372 return DotToDescriptor(name->ToModifiedUtf8().c_str()); 3373} 3374 3375mirror::ArtMethod* ClassLinker::FindMethodForProxy(mirror::Class* proxy_class, 3376 mirror::ArtMethod* proxy_method) { 3377 DCHECK(proxy_class->IsProxyClass()); 3378 DCHECK(proxy_method->IsProxyMethod()); 3379 { 3380 ReaderMutexLock mu(Thread::Current(), dex_lock_); 3381 // Locate the dex cache of the original interface/Object 3382 for (const GcRoot<mirror::DexCache>& root : dex_caches_) { 3383 auto* dex_cache = root.Read(); 3384 if (proxy_method->HasSameDexCacheResolvedTypes(dex_cache->GetResolvedTypes())) { 3385 mirror::ArtMethod* resolved_method = dex_cache->GetResolvedMethod( 3386 proxy_method->GetDexMethodIndex()); 3387 CHECK(resolved_method != nullptr); 3388 return resolved_method; 3389 } 3390 } 3391 } 3392 LOG(FATAL) << "Didn't find dex cache for " << PrettyClass(proxy_class) << " " 3393 << PrettyMethod(proxy_method); 3394 UNREACHABLE(); 3395} 3396 3397 3398mirror::ArtMethod* ClassLinker::CreateProxyConstructor(Thread* self, 3399 Handle<mirror::Class> klass, 3400 mirror::Class* proxy_class) { 3401 // Create constructor for Proxy that must initialize h 3402 mirror::ObjectArray<mirror::ArtMethod>* proxy_direct_methods = 3403 proxy_class->GetDirectMethods(); 3404 CHECK_EQ(proxy_direct_methods->GetLength(), 16); 3405 mirror::ArtMethod* proxy_constructor = proxy_direct_methods->Get(2); 3406 // Ensure constructor is in dex cache so that we can use the dex cache to look up the overridden 3407 // constructor method. 3408 proxy_class->GetDexCache()->SetResolvedMethod(proxy_constructor->GetDexMethodIndex(), 3409 proxy_constructor); 3410 // Clone the existing constructor of Proxy (our constructor would just invoke it so steal its 3411 // code_ too) 3412 mirror::ArtMethod* constructor = down_cast<mirror::ArtMethod*>(proxy_constructor->Clone(self)); 3413 if (constructor == nullptr) { 3414 CHECK(self->IsExceptionPending()); // OOME. 3415 return nullptr; 3416 } 3417 // Make this constructor public and fix the class to be our Proxy version 3418 constructor->SetAccessFlags((constructor->GetAccessFlags() & ~kAccProtected) | kAccPublic); 3419 constructor->SetDeclaringClass(klass.Get()); 3420 return constructor; 3421} 3422 3423static void CheckProxyConstructor(mirror::ArtMethod* constructor) 3424 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3425 CHECK(constructor->IsConstructor()); 3426 CHECK_STREQ(constructor->GetName(), "<init>"); 3427 CHECK_STREQ(constructor->GetSignature().ToString().c_str(), 3428 "(Ljava/lang/reflect/InvocationHandler;)V"); 3429 DCHECK(constructor->IsPublic()); 3430} 3431 3432mirror::ArtMethod* ClassLinker::CreateProxyMethod(Thread* self, 3433 Handle<mirror::Class> klass, 3434 Handle<mirror::ArtMethod> prototype) { 3435 // Ensure prototype is in dex cache so that we can use the dex cache to look up the overridden 3436 // prototype method 3437 auto* dex_cache = prototype->GetDeclaringClass()->GetDexCache(); 3438 // Avoid dirtying the dex cache unless we need to. 3439 if (dex_cache->GetResolvedMethod(prototype->GetDexMethodIndex()) != prototype.Get()) { 3440 dex_cache->SetResolvedMethod(prototype->GetDexMethodIndex(), prototype.Get()); 3441 } 3442 // We steal everything from the prototype (such as DexCache, invoke stub, etc.) then specialize 3443 // as necessary 3444 mirror::ArtMethod* method = down_cast<mirror::ArtMethod*>(prototype->Clone(self)); 3445 if (UNLIKELY(method == nullptr)) { 3446 CHECK(self->IsExceptionPending()); // OOME. 3447 return nullptr; 3448 } 3449 3450 // Set class to be the concrete proxy class and clear the abstract flag, modify exceptions to 3451 // the intersection of throw exceptions as defined in Proxy 3452 method->SetDeclaringClass(klass.Get()); 3453 method->SetAccessFlags((method->GetAccessFlags() & ~kAccAbstract) | kAccFinal); 3454 3455 // At runtime the method looks like a reference and argument saving method, clone the code 3456 // related parameters from this method. 3457 method->SetEntryPointFromQuickCompiledCode(GetQuickProxyInvokeHandler()); 3458 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 3459 3460 return method; 3461} 3462 3463static void CheckProxyMethod(Handle<mirror::ArtMethod> method, 3464 Handle<mirror::ArtMethod> prototype) 3465 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3466 // Basic sanity 3467 CHECK(!prototype->IsFinal()); 3468 CHECK(method->IsFinal()); 3469 CHECK(!method->IsAbstract()); 3470 3471 // The proxy method doesn't have its own dex cache or dex file and so it steals those of its 3472 // interface prototype. The exception to this are Constructors and the Class of the Proxy itself. 3473 CHECK(prototype->HasSameDexCacheResolvedMethods(method.Get())); 3474 CHECK(prototype->HasSameDexCacheResolvedTypes(method.Get())); 3475 CHECK_EQ(prototype->GetDeclaringClass()->GetDexCache(), method->GetDexCache()); 3476 CHECK_EQ(prototype->GetDexMethodIndex(), method->GetDexMethodIndex()); 3477 3478 CHECK_STREQ(method->GetName(), prototype->GetName()); 3479 CHECK_STREQ(method->GetShorty(), prototype->GetShorty()); 3480 // More complex sanity - via dex cache 3481 CHECK_EQ(method->GetInterfaceMethodIfProxy()->GetReturnType(), prototype->GetReturnType()); 3482} 3483 3484static bool CanWeInitializeClass(mirror::Class* klass, bool can_init_statics, 3485 bool can_init_parents) 3486 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3487 if (can_init_statics && can_init_parents) { 3488 return true; 3489 } 3490 if (!can_init_statics) { 3491 // Check if there's a class initializer. 3492 mirror::ArtMethod* clinit = klass->FindClassInitializer(); 3493 if (clinit != nullptr) { 3494 return false; 3495 } 3496 // Check if there are encoded static values needing initialization. 3497 if (klass->NumStaticFields() != 0) { 3498 const DexFile::ClassDef* dex_class_def = klass->GetClassDef(); 3499 DCHECK(dex_class_def != nullptr); 3500 if (dex_class_def->static_values_off_ != 0) { 3501 return false; 3502 } 3503 } 3504 } 3505 if (!klass->IsInterface() && klass->HasSuperClass()) { 3506 mirror::Class* super_class = klass->GetSuperClass(); 3507 if (!can_init_parents && !super_class->IsInitialized()) { 3508 return false; 3509 } else { 3510 if (!CanWeInitializeClass(super_class, can_init_statics, can_init_parents)) { 3511 return false; 3512 } 3513 } 3514 } 3515 return true; 3516} 3517 3518bool ClassLinker::InitializeClass(Thread* self, Handle<mirror::Class> klass, 3519 bool can_init_statics, bool can_init_parents) { 3520 // see JLS 3rd edition, 12.4.2 "Detailed Initialization Procedure" for the locking protocol 3521 3522 // Are we already initialized and therefore done? 3523 // Note: we differ from the JLS here as we don't do this under the lock, this is benign as 3524 // an initialized class will never change its state. 3525 if (klass->IsInitialized()) { 3526 return true; 3527 } 3528 3529 // Fast fail if initialization requires a full runtime. Not part of the JLS. 3530 if (!CanWeInitializeClass(klass.Get(), can_init_statics, can_init_parents)) { 3531 return false; 3532 } 3533 3534 self->AllowThreadSuspension(); 3535 uint64_t t0; 3536 { 3537 ObjectLock<mirror::Class> lock(self, klass); 3538 3539 // Re-check under the lock in case another thread initialized ahead of us. 3540 if (klass->IsInitialized()) { 3541 return true; 3542 } 3543 3544 // Was the class already found to be erroneous? Done under the lock to match the JLS. 3545 if (klass->IsErroneous()) { 3546 ThrowEarlierClassFailure(klass.Get()); 3547 VlogClassInitializationFailure(klass); 3548 return false; 3549 } 3550 3551 CHECK(klass->IsResolved()) << PrettyClass(klass.Get()) << ": state=" << klass->GetStatus(); 3552 3553 if (!klass->IsVerified()) { 3554 VerifyClass(self, klass); 3555 if (!klass->IsVerified()) { 3556 // We failed to verify, expect either the klass to be erroneous or verification failed at 3557 // compile time. 3558 if (klass->IsErroneous()) { 3559 CHECK(self->IsExceptionPending()); 3560 VlogClassInitializationFailure(klass); 3561 } else { 3562 CHECK(Runtime::Current()->IsAotCompiler()); 3563 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime); 3564 } 3565 return false; 3566 } else { 3567 self->AssertNoPendingException(); 3568 } 3569 } 3570 3571 // If the class is kStatusInitializing, either this thread is 3572 // initializing higher up the stack or another thread has beat us 3573 // to initializing and we need to wait. Either way, this 3574 // invocation of InitializeClass will not be responsible for 3575 // running <clinit> and will return. 3576 if (klass->GetStatus() == mirror::Class::kStatusInitializing) { 3577 // Could have got an exception during verification. 3578 if (self->IsExceptionPending()) { 3579 VlogClassInitializationFailure(klass); 3580 return false; 3581 } 3582 // We caught somebody else in the act; was it us? 3583 if (klass->GetClinitThreadId() == self->GetTid()) { 3584 // Yes. That's fine. Return so we can continue initializing. 3585 return true; 3586 } 3587 // No. That's fine. Wait for another thread to finish initializing. 3588 return WaitForInitializeClass(klass, self, lock); 3589 } 3590 3591 if (!ValidateSuperClassDescriptors(klass)) { 3592 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3593 return false; 3594 } 3595 self->AllowThreadSuspension(); 3596 3597 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusVerified) << PrettyClass(klass.Get()); 3598 3599 // From here out other threads may observe that we're initializing and so changes of state 3600 // require the a notification. 3601 klass->SetClinitThreadId(self->GetTid()); 3602 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitializing, self); 3603 3604 t0 = NanoTime(); 3605 } 3606 3607 // Initialize super classes, must be done while initializing for the JLS. 3608 if (!klass->IsInterface() && klass->HasSuperClass()) { 3609 mirror::Class* super_class = klass->GetSuperClass(); 3610 if (!super_class->IsInitialized()) { 3611 CHECK(!super_class->IsInterface()); 3612 CHECK(can_init_parents); 3613 StackHandleScope<1> hs(self); 3614 Handle<mirror::Class> handle_scope_super(hs.NewHandle(super_class)); 3615 bool super_initialized = InitializeClass(self, handle_scope_super, can_init_statics, true); 3616 if (!super_initialized) { 3617 // The super class was verified ahead of entering initializing, we should only be here if 3618 // the super class became erroneous due to initialization. 3619 CHECK(handle_scope_super->IsErroneous() && self->IsExceptionPending()) 3620 << "Super class initialization failed for " 3621 << PrettyDescriptor(handle_scope_super.Get()) 3622 << " that has unexpected status " << handle_scope_super->GetStatus() 3623 << "\nPending exception:\n" 3624 << (self->GetException() != nullptr ? self->GetException()->Dump() : ""); 3625 ObjectLock<mirror::Class> lock(self, klass); 3626 // Initialization failed because the super-class is erroneous. 3627 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3628 return false; 3629 } 3630 } 3631 } 3632 3633 const size_t num_static_fields = klass->NumStaticFields(); 3634 if (num_static_fields > 0) { 3635 const DexFile::ClassDef* dex_class_def = klass->GetClassDef(); 3636 CHECK(dex_class_def != nullptr); 3637 const DexFile& dex_file = klass->GetDexFile(); 3638 StackHandleScope<3> hs(self); 3639 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(klass->GetClassLoader())); 3640 Handle<mirror::DexCache> dex_cache(hs.NewHandle(klass->GetDexCache())); 3641 3642 // Eagerly fill in static fields so that the we don't have to do as many expensive 3643 // Class::FindStaticField in ResolveField. 3644 for (size_t i = 0; i < num_static_fields; ++i) { 3645 ArtField* field = klass->GetStaticField(i); 3646 const uint32_t field_idx = field->GetDexFieldIndex(); 3647 ArtField* resolved_field = dex_cache->GetResolvedField(field_idx, image_pointer_size_); 3648 if (resolved_field == nullptr) { 3649 dex_cache->SetResolvedField(field_idx, field, image_pointer_size_); 3650 } else { 3651 DCHECK_EQ(field, resolved_field); 3652 } 3653 } 3654 3655 EncodedStaticFieldValueIterator value_it(dex_file, &dex_cache, &class_loader, 3656 this, *dex_class_def); 3657 const uint8_t* class_data = dex_file.GetClassData(*dex_class_def); 3658 ClassDataItemIterator field_it(dex_file, class_data); 3659 if (value_it.HasNext()) { 3660 DCHECK(field_it.HasNextStaticField()); 3661 CHECK(can_init_statics); 3662 for ( ; value_it.HasNext(); value_it.Next(), field_it.Next()) { 3663 ArtField* field = ResolveField( 3664 dex_file, field_it.GetMemberIndex(), dex_cache, class_loader, true); 3665 if (Runtime::Current()->IsActiveTransaction()) { 3666 value_it.ReadValueToField<true>(field); 3667 } else { 3668 value_it.ReadValueToField<false>(field); 3669 } 3670 DCHECK(!value_it.HasNext() || field_it.HasNextStaticField()); 3671 } 3672 } 3673 } 3674 3675 mirror::ArtMethod* clinit = klass->FindClassInitializer(); 3676 if (clinit != nullptr) { 3677 CHECK(can_init_statics); 3678 JValue result; 3679 clinit->Invoke(self, nullptr, 0, &result, "V"); 3680 } 3681 3682 self->AllowThreadSuspension(); 3683 uint64_t t1 = NanoTime(); 3684 3685 bool success = true; 3686 { 3687 ObjectLock<mirror::Class> lock(self, klass); 3688 3689 if (self->IsExceptionPending()) { 3690 WrapExceptionInInitializer(klass); 3691 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3692 success = false; 3693 } else if (Runtime::Current()->IsTransactionAborted()) { 3694 // The exception thrown when the transaction aborted has been caught and cleared 3695 // so we need to throw it again now. 3696 VLOG(compiler) << "Return from class initializer of " << PrettyDescriptor(klass.Get()) 3697 << " without exception while transaction was aborted: re-throw it now."; 3698 Runtime::Current()->ThrowTransactionAbortError(self); 3699 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3700 success = false; 3701 } else { 3702 RuntimeStats* global_stats = Runtime::Current()->GetStats(); 3703 RuntimeStats* thread_stats = self->GetStats(); 3704 ++global_stats->class_init_count; 3705 ++thread_stats->class_init_count; 3706 global_stats->class_init_time_ns += (t1 - t0); 3707 thread_stats->class_init_time_ns += (t1 - t0); 3708 // Set the class as initialized except if failed to initialize static fields. 3709 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitialized, self); 3710 if (VLOG_IS_ON(class_linker)) { 3711 std::string temp; 3712 LOG(INFO) << "Initialized class " << klass->GetDescriptor(&temp) << " from " << 3713 klass->GetLocation(); 3714 } 3715 // Opportunistically set static method trampolines to their destination. 3716 FixupStaticTrampolines(klass.Get()); 3717 } 3718 } 3719 return success; 3720} 3721 3722bool ClassLinker::WaitForInitializeClass(Handle<mirror::Class> klass, Thread* self, 3723 ObjectLock<mirror::Class>& lock) 3724 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3725 while (true) { 3726 self->AssertNoPendingException(); 3727 CHECK(!klass->IsInitialized()); 3728 lock.WaitIgnoringInterrupts(); 3729 3730 // When we wake up, repeat the test for init-in-progress. If 3731 // there's an exception pending (only possible if 3732 // we were not using WaitIgnoringInterrupts), bail out. 3733 if (self->IsExceptionPending()) { 3734 WrapExceptionInInitializer(klass); 3735 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3736 return false; 3737 } 3738 // Spurious wakeup? Go back to waiting. 3739 if (klass->GetStatus() == mirror::Class::kStatusInitializing) { 3740 continue; 3741 } 3742 if (klass->GetStatus() == mirror::Class::kStatusVerified && 3743 Runtime::Current()->IsAotCompiler()) { 3744 // Compile time initialization failed. 3745 return false; 3746 } 3747 if (klass->IsErroneous()) { 3748 // The caller wants an exception, but it was thrown in a 3749 // different thread. Synthesize one here. 3750 ThrowNoClassDefFoundError("<clinit> failed for class %s; see exception in other thread", 3751 PrettyDescriptor(klass.Get()).c_str()); 3752 VlogClassInitializationFailure(klass); 3753 return false; 3754 } 3755 if (klass->IsInitialized()) { 3756 return true; 3757 } 3758 LOG(FATAL) << "Unexpected class status. " << PrettyClass(klass.Get()) << " is " 3759 << klass->GetStatus(); 3760 } 3761 UNREACHABLE(); 3762} 3763 3764static bool HasSameSignatureWithDifferentClassLoaders(Thread* self, 3765 Handle<mirror::ArtMethod> method1, 3766 Handle<mirror::ArtMethod> method2, 3767 std::string* error_msg) 3768 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3769 { 3770 StackHandleScope<1> hs(self); 3771 Handle<mirror::Class> return_type(hs.NewHandle(method1->GetReturnType())); 3772 mirror::Class* other_return_type = method2->GetReturnType(); 3773 // NOTE: return_type.Get() must be sequenced after method2->GetReturnType(). 3774 if (UNLIKELY(other_return_type != return_type.Get())) { 3775 *error_msg = StringPrintf("Return types mismatch: %s(%p) vs %s(%p)", 3776 PrettyClassAndClassLoader(return_type.Get()).c_str(), 3777 return_type.Get(), 3778 PrettyClassAndClassLoader(other_return_type).c_str(), 3779 other_return_type); 3780 return false; 3781 } 3782 } 3783 const DexFile::TypeList* types1 = method1->GetParameterTypeList(); 3784 const DexFile::TypeList* types2 = method2->GetParameterTypeList(); 3785 if (types1 == nullptr) { 3786 if (types2 != nullptr && types2->Size() != 0) { 3787 *error_msg = StringPrintf("Type list mismatch with %s", 3788 PrettyMethod(method2.Get(), true).c_str()); 3789 return false; 3790 } 3791 return true; 3792 } else if (UNLIKELY(types2 == nullptr)) { 3793 if (types1->Size() != 0) { 3794 *error_msg = StringPrintf("Type list mismatch with %s", 3795 PrettyMethod(method2.Get(), true).c_str()); 3796 return false; 3797 } 3798 return true; 3799 } 3800 uint32_t num_types = types1->Size(); 3801 if (UNLIKELY(num_types != types2->Size())) { 3802 *error_msg = StringPrintf("Type list mismatch with %s", 3803 PrettyMethod(method2.Get(), true).c_str()); 3804 return false; 3805 } 3806 for (uint32_t i = 0; i < num_types; ++i) { 3807 StackHandleScope<1> hs(self); 3808 Handle<mirror::Class> param_type(hs.NewHandle( 3809 method1->GetClassFromTypeIndex(types1->GetTypeItem(i).type_idx_, true))); 3810 mirror::Class* other_param_type = 3811 method2->GetClassFromTypeIndex(types2->GetTypeItem(i).type_idx_, true); 3812 // NOTE: param_type.Get() must be sequenced after method2->GetClassFromTypeIndex(...). 3813 if (UNLIKELY(param_type.Get() != other_param_type)) { 3814 *error_msg = StringPrintf("Parameter %u type mismatch: %s(%p) vs %s(%p)", 3815 i, 3816 PrettyClassAndClassLoader(param_type.Get()).c_str(), 3817 param_type.Get(), 3818 PrettyClassAndClassLoader(other_param_type).c_str(), 3819 other_param_type); 3820 return false; 3821 } 3822 } 3823 return true; 3824} 3825 3826 3827bool ClassLinker::ValidateSuperClassDescriptors(Handle<mirror::Class> klass) { 3828 if (klass->IsInterface()) { 3829 return true; 3830 } 3831 // Begin with the methods local to the superclass. 3832 Thread* self = Thread::Current(); 3833 StackHandleScope<2> hs(self); 3834 MutableHandle<mirror::ArtMethod> h_m(hs.NewHandle<mirror::ArtMethod>(nullptr)); 3835 MutableHandle<mirror::ArtMethod> super_h_m(hs.NewHandle<mirror::ArtMethod>(nullptr)); 3836 if (klass->HasSuperClass() && 3837 klass->GetClassLoader() != klass->GetSuperClass()->GetClassLoader()) { 3838 for (int i = klass->GetSuperClass()->GetVTableLength() - 1; i >= 0; --i) { 3839 h_m.Assign(klass->GetVTableEntry(i)); 3840 super_h_m.Assign(klass->GetSuperClass()->GetVTableEntry(i)); 3841 if (h_m.Get() != super_h_m.Get()) { 3842 std::string error_msg; 3843 if (!HasSameSignatureWithDifferentClassLoaders(self, h_m, super_h_m, &error_msg)) { 3844 ThrowLinkageError(klass.Get(), 3845 "Class %s method %s resolves differently in superclass %s: %s", 3846 PrettyDescriptor(klass.Get()).c_str(), 3847 PrettyMethod(h_m.Get()).c_str(), 3848 PrettyDescriptor(klass->GetSuperClass()).c_str(), 3849 error_msg.c_str()); 3850 return false; 3851 } 3852 } 3853 } 3854 } 3855 for (int32_t i = 0; i < klass->GetIfTableCount(); ++i) { 3856 if (klass->GetClassLoader() != klass->GetIfTable()->GetInterface(i)->GetClassLoader()) { 3857 uint32_t num_methods = klass->GetIfTable()->GetInterface(i)->NumVirtualMethods(); 3858 for (uint32_t j = 0; j < num_methods; ++j) { 3859 h_m.Assign(klass->GetIfTable()->GetMethodArray(i)->GetWithoutChecks(j)); 3860 super_h_m.Assign(klass->GetIfTable()->GetInterface(i)->GetVirtualMethod(j)); 3861 if (h_m.Get() != super_h_m.Get()) { 3862 std::string error_msg; 3863 if (!HasSameSignatureWithDifferentClassLoaders(self, h_m, super_h_m, &error_msg)) { 3864 ThrowLinkageError(klass.Get(), 3865 "Class %s method %s resolves differently in interface %s: %s", 3866 PrettyDescriptor(klass.Get()).c_str(), 3867 PrettyMethod(h_m.Get()).c_str(), 3868 PrettyDescriptor(klass->GetIfTable()->GetInterface(i)).c_str(), 3869 error_msg.c_str()); 3870 return false; 3871 } 3872 } 3873 } 3874 } 3875 } 3876 return true; 3877} 3878 3879bool ClassLinker::EnsureInitialized(Thread* self, Handle<mirror::Class> c, bool can_init_fields, 3880 bool can_init_parents) { 3881 DCHECK(c.Get() != nullptr); 3882 if (c->IsInitialized()) { 3883 EnsurePreverifiedMethods(c); 3884 return true; 3885 } 3886 const bool success = InitializeClass(self, c, can_init_fields, can_init_parents); 3887 if (!success) { 3888 if (can_init_fields && can_init_parents) { 3889 CHECK(self->IsExceptionPending()) << PrettyClass(c.Get()); 3890 } 3891 } else { 3892 self->AssertNoPendingException(); 3893 } 3894 return success; 3895} 3896 3897void ClassLinker::FixupTemporaryDeclaringClass(mirror::Class* temp_class, mirror::Class* new_class) { 3898 ArtField* fields = new_class->GetIFields(); 3899 for (size_t i = 0, count = new_class->NumInstanceFields(); i < count; i++) { 3900 if (fields[i].GetDeclaringClass() == temp_class) { 3901 fields[i].SetDeclaringClass(new_class); 3902 } 3903 } 3904 3905 fields = new_class->GetSFields(); 3906 for (size_t i = 0, count = new_class->NumStaticFields(); i < count; i++) { 3907 if (fields[i].GetDeclaringClass() == temp_class) { 3908 fields[i].SetDeclaringClass(new_class); 3909 } 3910 } 3911 3912 mirror::ObjectArray<mirror::ArtMethod>* methods = new_class->GetDirectMethods(); 3913 if (methods != nullptr) { 3914 for (int index = 0; index < methods->GetLength(); index ++) { 3915 if (methods->Get(index)->GetDeclaringClass() == temp_class) { 3916 methods->Get(index)->SetDeclaringClass(new_class); 3917 } 3918 } 3919 } 3920 3921 methods = new_class->GetVirtualMethods(); 3922 if (methods != nullptr) { 3923 for (int index = 0; index < methods->GetLength(); index ++) { 3924 if (methods->Get(index)->GetDeclaringClass() == temp_class) { 3925 methods->Get(index)->SetDeclaringClass(new_class); 3926 } 3927 } 3928 } 3929} 3930 3931bool ClassLinker::LinkClass(Thread* self, const char* descriptor, Handle<mirror::Class> klass, 3932 Handle<mirror::ObjectArray<mirror::Class>> interfaces, 3933 mirror::Class** new_class) { 3934 CHECK_EQ(mirror::Class::kStatusLoaded, klass->GetStatus()); 3935 3936 if (!LinkSuperClass(klass)) { 3937 return false; 3938 } 3939 StackHandleScope<mirror::Class::kImtSize> imt_handle_scope( 3940 self, Runtime::Current()->GetImtUnimplementedMethod()); 3941 if (!LinkMethods(self, klass, interfaces, &imt_handle_scope)) { 3942 return false; 3943 } 3944 if (!LinkInstanceFields(self, klass)) { 3945 return false; 3946 } 3947 size_t class_size; 3948 if (!LinkStaticFields(self, klass, &class_size)) { 3949 return false; 3950 } 3951 CreateReferenceInstanceOffsets(klass); 3952 CHECK_EQ(mirror::Class::kStatusLoaded, klass->GetStatus()); 3953 3954 if (!klass->IsTemp() || (!init_done_ && klass->GetClassSize() == class_size)) { 3955 // We don't need to retire this class as it has no embedded tables or it was created the 3956 // correct size during class linker initialization. 3957 CHECK_EQ(klass->GetClassSize(), class_size) << PrettyDescriptor(klass.Get()); 3958 3959 if (klass->ShouldHaveEmbeddedImtAndVTable()) { 3960 klass->PopulateEmbeddedImtAndVTable(&imt_handle_scope); 3961 } 3962 3963 // This will notify waiters on klass that saw the not yet resolved 3964 // class in the class_table_ during EnsureResolved. 3965 mirror::Class::SetStatus(klass, mirror::Class::kStatusResolved, self); 3966 *new_class = klass.Get(); 3967 } else { 3968 CHECK(!klass->IsResolved()); 3969 // Retire the temporary class and create the correctly sized resolved class. 3970 *new_class = klass->CopyOf(self, class_size, &imt_handle_scope); 3971 if (UNLIKELY(*new_class == nullptr)) { 3972 CHECK(self->IsExceptionPending()); // Expect an OOME. 3973 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3974 return false; 3975 } 3976 3977 CHECK_EQ((*new_class)->GetClassSize(), class_size); 3978 StackHandleScope<1> hs(self); 3979 auto new_class_h = hs.NewHandleWrapper<mirror::Class>(new_class); 3980 ObjectLock<mirror::Class> lock(self, new_class_h); 3981 3982 FixupTemporaryDeclaringClass(klass.Get(), new_class_h.Get()); 3983 3984 mirror::Class* existing = UpdateClass(descriptor, new_class_h.Get(), 3985 ComputeModifiedUtf8Hash(descriptor)); 3986 CHECK(existing == nullptr || existing == klass.Get()); 3987 3988 // This will notify waiters on temp class that saw the not yet resolved class in the 3989 // class_table_ during EnsureResolved. 3990 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetired, self); 3991 3992 CHECK_EQ(new_class_h->GetStatus(), mirror::Class::kStatusResolving); 3993 // This will notify waiters on new_class that saw the not yet resolved 3994 // class in the class_table_ during EnsureResolved. 3995 mirror::Class::SetStatus(new_class_h, mirror::Class::kStatusResolved, self); 3996 } 3997 return true; 3998} 3999 4000static void CountMethodsAndFields(ClassDataItemIterator& dex_data, 4001 size_t* virtual_methods, 4002 size_t* direct_methods, 4003 size_t* static_fields, 4004 size_t* instance_fields) { 4005 *virtual_methods = *direct_methods = *static_fields = *instance_fields = 0; 4006 4007 while (dex_data.HasNextStaticField()) { 4008 dex_data.Next(); 4009 (*static_fields)++; 4010 } 4011 while (dex_data.HasNextInstanceField()) { 4012 dex_data.Next(); 4013 (*instance_fields)++; 4014 } 4015 while (dex_data.HasNextDirectMethod()) { 4016 (*direct_methods)++; 4017 dex_data.Next(); 4018 } 4019 while (dex_data.HasNextVirtualMethod()) { 4020 (*virtual_methods)++; 4021 dex_data.Next(); 4022 } 4023 DCHECK(!dex_data.HasNext()); 4024} 4025 4026static void DumpClass(std::ostream& os, 4027 const DexFile& dex_file, const DexFile::ClassDef& dex_class_def, 4028 const char* suffix) { 4029 ClassDataItemIterator dex_data(dex_file, dex_file.GetClassData(dex_class_def)); 4030 os << dex_file.GetClassDescriptor(dex_class_def) << suffix << ":\n"; 4031 os << " Static fields:\n"; 4032 while (dex_data.HasNextStaticField()) { 4033 const DexFile::FieldId& id = dex_file.GetFieldId(dex_data.GetMemberIndex()); 4034 os << " " << dex_file.GetFieldTypeDescriptor(id) << " " << dex_file.GetFieldName(id) << "\n"; 4035 dex_data.Next(); 4036 } 4037 os << " Instance fields:\n"; 4038 while (dex_data.HasNextInstanceField()) { 4039 const DexFile::FieldId& id = dex_file.GetFieldId(dex_data.GetMemberIndex()); 4040 os << " " << dex_file.GetFieldTypeDescriptor(id) << " " << dex_file.GetFieldName(id) << "\n"; 4041 dex_data.Next(); 4042 } 4043 os << " Direct methods:\n"; 4044 while (dex_data.HasNextDirectMethod()) { 4045 const DexFile::MethodId& id = dex_file.GetMethodId(dex_data.GetMemberIndex()); 4046 os << " " << dex_file.GetMethodName(id) << dex_file.GetMethodSignature(id).ToString() << "\n"; 4047 dex_data.Next(); 4048 } 4049 os << " Virtual methods:\n"; 4050 while (dex_data.HasNextVirtualMethod()) { 4051 const DexFile::MethodId& id = dex_file.GetMethodId(dex_data.GetMemberIndex()); 4052 os << " " << dex_file.GetMethodName(id) << dex_file.GetMethodSignature(id).ToString() << "\n"; 4053 dex_data.Next(); 4054 } 4055} 4056 4057static std::string DumpClasses(const DexFile& dex_file1, const DexFile::ClassDef& dex_class_def1, 4058 const DexFile& dex_file2, const DexFile::ClassDef& dex_class_def2) { 4059 std::ostringstream os; 4060 DumpClass(os, dex_file1, dex_class_def1, " (Compile time)"); 4061 DumpClass(os, dex_file2, dex_class_def2, " (Runtime)"); 4062 return os.str(); 4063} 4064 4065 4066// Very simple structural check on whether the classes match. Only compares the number of 4067// methods and fields. 4068static bool SimpleStructuralCheck(const DexFile& dex_file1, const DexFile::ClassDef& dex_class_def1, 4069 const DexFile& dex_file2, const DexFile::ClassDef& dex_class_def2, 4070 std::string* error_msg) { 4071 ClassDataItemIterator dex_data1(dex_file1, dex_file1.GetClassData(dex_class_def1)); 4072 ClassDataItemIterator dex_data2(dex_file2, dex_file2.GetClassData(dex_class_def2)); 4073 4074 // Counters for current dex file. 4075 size_t dex_virtual_methods1, dex_direct_methods1, dex_static_fields1, dex_instance_fields1; 4076 CountMethodsAndFields(dex_data1, &dex_virtual_methods1, &dex_direct_methods1, &dex_static_fields1, 4077 &dex_instance_fields1); 4078 // Counters for compile-time dex file. 4079 size_t dex_virtual_methods2, dex_direct_methods2, dex_static_fields2, dex_instance_fields2; 4080 CountMethodsAndFields(dex_data2, &dex_virtual_methods2, &dex_direct_methods2, &dex_static_fields2, 4081 &dex_instance_fields2); 4082 4083 if (dex_virtual_methods1 != dex_virtual_methods2) { 4084 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 4085 *error_msg = StringPrintf("Virtual method count off: %zu vs %zu\n%s", dex_virtual_methods1, 4086 dex_virtual_methods2, class_dump.c_str()); 4087 return false; 4088 } 4089 if (dex_direct_methods1 != dex_direct_methods2) { 4090 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 4091 *error_msg = StringPrintf("Direct method count off: %zu vs %zu\n%s", dex_direct_methods1, 4092 dex_direct_methods2, class_dump.c_str()); 4093 return false; 4094 } 4095 if (dex_static_fields1 != dex_static_fields2) { 4096 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 4097 *error_msg = StringPrintf("Static field count off: %zu vs %zu\n%s", dex_static_fields1, 4098 dex_static_fields2, class_dump.c_str()); 4099 return false; 4100 } 4101 if (dex_instance_fields1 != dex_instance_fields2) { 4102 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 4103 *error_msg = StringPrintf("Instance field count off: %zu vs %zu\n%s", dex_instance_fields1, 4104 dex_instance_fields2, class_dump.c_str()); 4105 return false; 4106 } 4107 4108 return true; 4109} 4110 4111// Checks whether a the super-class changed from what we had at compile-time. This would 4112// invalidate quickening. 4113static bool CheckSuperClassChange(Handle<mirror::Class> klass, 4114 const DexFile& dex_file, 4115 const DexFile::ClassDef& class_def, 4116 mirror::Class* super_class) 4117 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4118 // Check for unexpected changes in the superclass. 4119 // Quick check 1) is the super_class class-loader the boot class loader? This always has 4120 // precedence. 4121 if (super_class->GetClassLoader() != nullptr && 4122 // Quick check 2) different dex cache? Breaks can only occur for different dex files, 4123 // which is implied by different dex cache. 4124 klass->GetDexCache() != super_class->GetDexCache()) { 4125 // Now comes the expensive part: things can be broken if (a) the klass' dex file has a 4126 // definition for the super-class, and (b) the files are in separate oat files. The oat files 4127 // are referenced from the dex file, so do (b) first. Only relevant if we have oat files. 4128 const OatDexFile* class_oat_dex_file = dex_file.GetOatDexFile(); 4129 const OatFile* class_oat_file = nullptr; 4130 if (class_oat_dex_file != nullptr) { 4131 class_oat_file = class_oat_dex_file->GetOatFile(); 4132 } 4133 4134 if (class_oat_file != nullptr) { 4135 const OatDexFile* loaded_super_oat_dex_file = super_class->GetDexFile().GetOatDexFile(); 4136 const OatFile* loaded_super_oat_file = nullptr; 4137 if (loaded_super_oat_dex_file != nullptr) { 4138 loaded_super_oat_file = loaded_super_oat_dex_file->GetOatFile(); 4139 } 4140 4141 if (loaded_super_oat_file != nullptr && class_oat_file != loaded_super_oat_file) { 4142 // Now check (a). 4143 const DexFile::ClassDef* super_class_def = dex_file.FindClassDef(class_def.superclass_idx_); 4144 if (super_class_def != nullptr) { 4145 // Uh-oh, we found something. Do our check. 4146 std::string error_msg; 4147 if (!SimpleStructuralCheck(dex_file, *super_class_def, 4148 super_class->GetDexFile(), *super_class->GetClassDef(), 4149 &error_msg)) { 4150 // Print a warning to the log. This exception might be caught, e.g., as common in test 4151 // drivers. When the class is later tried to be used, we re-throw a new instance, as we 4152 // only save the type of the exception. 4153 LOG(WARNING) << "Incompatible structural change detected: " << 4154 StringPrintf( 4155 "Structural change of %s is hazardous (%s at compile time, %s at runtime): %s", 4156 PrettyType(super_class_def->class_idx_, dex_file).c_str(), 4157 class_oat_file->GetLocation().c_str(), 4158 loaded_super_oat_file->GetLocation().c_str(), 4159 error_msg.c_str()); 4160 ThrowIncompatibleClassChangeError(klass.Get(), 4161 "Structural change of %s is hazardous (%s at compile time, %s at runtime): %s", 4162 PrettyType(super_class_def->class_idx_, dex_file).c_str(), 4163 class_oat_file->GetLocation().c_str(), 4164 loaded_super_oat_file->GetLocation().c_str(), 4165 error_msg.c_str()); 4166 return false; 4167 } 4168 } 4169 } 4170 } 4171 } 4172 return true; 4173} 4174 4175bool ClassLinker::LoadSuperAndInterfaces(Handle<mirror::Class> klass, const DexFile& dex_file) { 4176 CHECK_EQ(mirror::Class::kStatusIdx, klass->GetStatus()); 4177 const DexFile::ClassDef& class_def = dex_file.GetClassDef(klass->GetDexClassDefIndex()); 4178 uint16_t super_class_idx = class_def.superclass_idx_; 4179 if (super_class_idx != DexFile::kDexNoIndex16) { 4180 mirror::Class* super_class = ResolveType(dex_file, super_class_idx, klass.Get()); 4181 if (super_class == nullptr) { 4182 DCHECK(Thread::Current()->IsExceptionPending()); 4183 return false; 4184 } 4185 // Verify 4186 if (!klass->CanAccess(super_class)) { 4187 ThrowIllegalAccessError(klass.Get(), "Class %s extended by class %s is inaccessible", 4188 PrettyDescriptor(super_class).c_str(), 4189 PrettyDescriptor(klass.Get()).c_str()); 4190 return false; 4191 } 4192 CHECK(super_class->IsResolved()); 4193 klass->SetSuperClass(super_class); 4194 4195 if (!CheckSuperClassChange(klass, dex_file, class_def, super_class)) { 4196 DCHECK(Thread::Current()->IsExceptionPending()); 4197 return false; 4198 } 4199 } 4200 const DexFile::TypeList* interfaces = dex_file.GetInterfacesList(class_def); 4201 if (interfaces != nullptr) { 4202 for (size_t i = 0; i < interfaces->Size(); i++) { 4203 uint16_t idx = interfaces->GetTypeItem(i).type_idx_; 4204 mirror::Class* interface = ResolveType(dex_file, idx, klass.Get()); 4205 if (interface == nullptr) { 4206 DCHECK(Thread::Current()->IsExceptionPending()); 4207 return false; 4208 } 4209 // Verify 4210 if (!klass->CanAccess(interface)) { 4211 // TODO: the RI seemed to ignore this in my testing. 4212 ThrowIllegalAccessError(klass.Get(), "Interface %s implemented by class %s is inaccessible", 4213 PrettyDescriptor(interface).c_str(), 4214 PrettyDescriptor(klass.Get()).c_str()); 4215 return false; 4216 } 4217 } 4218 } 4219 // Mark the class as loaded. 4220 mirror::Class::SetStatus(klass, mirror::Class::kStatusLoaded, nullptr); 4221 return true; 4222} 4223 4224bool ClassLinker::LinkSuperClass(Handle<mirror::Class> klass) { 4225 CHECK(!klass->IsPrimitive()); 4226 mirror::Class* super = klass->GetSuperClass(); 4227 if (klass.Get() == GetClassRoot(kJavaLangObject)) { 4228 if (super != nullptr) { 4229 ThrowClassFormatError(klass.Get(), "java.lang.Object must not have a superclass"); 4230 return false; 4231 } 4232 return true; 4233 } 4234 if (super == nullptr) { 4235 ThrowLinkageError(klass.Get(), "No superclass defined for class %s", 4236 PrettyDescriptor(klass.Get()).c_str()); 4237 return false; 4238 } 4239 // Verify 4240 if (super->IsFinal() || super->IsInterface()) { 4241 ThrowIncompatibleClassChangeError(klass.Get(), "Superclass %s of %s is %s", 4242 PrettyDescriptor(super).c_str(), 4243 PrettyDescriptor(klass.Get()).c_str(), 4244 super->IsFinal() ? "declared final" : "an interface"); 4245 return false; 4246 } 4247 if (!klass->CanAccess(super)) { 4248 ThrowIllegalAccessError(klass.Get(), "Superclass %s is inaccessible to class %s", 4249 PrettyDescriptor(super).c_str(), 4250 PrettyDescriptor(klass.Get()).c_str()); 4251 return false; 4252 } 4253 4254 // Inherit kAccClassIsFinalizable from the superclass in case this 4255 // class doesn't override finalize. 4256 if (super->IsFinalizable()) { 4257 klass->SetFinalizable(); 4258 } 4259 4260 // Inherit reference flags (if any) from the superclass. 4261 int reference_flags = (super->GetAccessFlags() & kAccReferenceFlagsMask); 4262 if (reference_flags != 0) { 4263 klass->SetAccessFlags(klass->GetAccessFlags() | reference_flags); 4264 } 4265 // Disallow custom direct subclasses of java.lang.ref.Reference. 4266 if (init_done_ && super == GetClassRoot(kJavaLangRefReference)) { 4267 ThrowLinkageError(klass.Get(), 4268 "Class %s attempts to subclass java.lang.ref.Reference, which is not allowed", 4269 PrettyDescriptor(klass.Get()).c_str()); 4270 return false; 4271 } 4272 4273 if (kIsDebugBuild) { 4274 // Ensure super classes are fully resolved prior to resolving fields.. 4275 while (super != nullptr) { 4276 CHECK(super->IsResolved()); 4277 super = super->GetSuperClass(); 4278 } 4279 } 4280 return true; 4281} 4282 4283// Populate the class vtable and itable. Compute return type indices. 4284bool ClassLinker::LinkMethods(Thread* self, Handle<mirror::Class> klass, 4285 Handle<mirror::ObjectArray<mirror::Class>> interfaces, 4286 StackHandleScope<mirror::Class::kImtSize>* out_imt) { 4287 self->AllowThreadSuspension(); 4288 if (klass->IsInterface()) { 4289 // No vtable. 4290 size_t count = klass->NumVirtualMethods(); 4291 if (!IsUint<16>(count)) { 4292 ThrowClassFormatError(klass.Get(), "Too many methods on interface: %zd", count); 4293 return false; 4294 } 4295 for (size_t i = 0; i < count; ++i) { 4296 klass->GetVirtualMethodDuringLinking(i)->SetMethodIndex(i); 4297 } 4298 } else if (!LinkVirtualMethods(self, klass)) { // Link virtual methods first. 4299 return false; 4300 } 4301 return LinkInterfaceMethods(self, klass, interfaces, out_imt); // Link interface method last. 4302} 4303 4304// Comparator for name and signature of a method, used in finding overriding methods. Implementation 4305// avoids the use of handles, if it didn't then rather than compare dex files we could compare dex 4306// caches in the implementation below. 4307class MethodNameAndSignatureComparator FINAL : public ValueObject { 4308 public: 4309 explicit MethodNameAndSignatureComparator(mirror::ArtMethod* method) 4310 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) : 4311 dex_file_(method->GetDexFile()), mid_(&dex_file_->GetMethodId(method->GetDexMethodIndex())), 4312 name_(nullptr), name_len_(0) { 4313 DCHECK(!method->IsProxyMethod()) << PrettyMethod(method); 4314 } 4315 4316 const char* GetName() { 4317 if (name_ == nullptr) { 4318 name_ = dex_file_->StringDataAndUtf16LengthByIdx(mid_->name_idx_, &name_len_); 4319 } 4320 return name_; 4321 } 4322 4323 bool HasSameNameAndSignature(mirror::ArtMethod* other) 4324 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4325 DCHECK(!other->IsProxyMethod()) << PrettyMethod(other); 4326 const DexFile* other_dex_file = other->GetDexFile(); 4327 const DexFile::MethodId& other_mid = other_dex_file->GetMethodId(other->GetDexMethodIndex()); 4328 if (dex_file_ == other_dex_file) { 4329 return mid_->name_idx_ == other_mid.name_idx_ && mid_->proto_idx_ == other_mid.proto_idx_; 4330 } 4331 GetName(); // Only used to make sure its calculated. 4332 uint32_t other_name_len; 4333 const char* other_name = other_dex_file->StringDataAndUtf16LengthByIdx(other_mid.name_idx_, 4334 &other_name_len); 4335 if (name_len_ != other_name_len || strcmp(name_, other_name) != 0) { 4336 return false; 4337 } 4338 return dex_file_->GetMethodSignature(*mid_) == other_dex_file->GetMethodSignature(other_mid); 4339 } 4340 4341 private: 4342 // Dex file for the method to compare against. 4343 const DexFile* const dex_file_; 4344 // MethodId for the method to compare against. 4345 const DexFile::MethodId* const mid_; 4346 // Lazily computed name from the dex file's strings. 4347 const char* name_; 4348 // Lazily computed name length. 4349 uint32_t name_len_; 4350}; 4351 4352class LinkVirtualHashTable { 4353 public: 4354 LinkVirtualHashTable(Handle<mirror::Class> klass, size_t hash_size, uint32_t* hash_table) 4355 : klass_(klass), hash_size_(hash_size), hash_table_(hash_table) { 4356 std::fill(hash_table_, hash_table_ + hash_size_, invalid_index_); 4357 } 4358 void Add(uint32_t virtual_method_index) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4359 mirror::ArtMethod* local_method = klass_->GetVirtualMethodDuringLinking(virtual_method_index); 4360 const char* name = local_method->GetName(); 4361 uint32_t hash = ComputeModifiedUtf8Hash(name); 4362 uint32_t index = hash % hash_size_; 4363 // Linear probe until we have an empty slot. 4364 while (hash_table_[index] != invalid_index_) { 4365 if (++index == hash_size_) { 4366 index = 0; 4367 } 4368 } 4369 hash_table_[index] = virtual_method_index; 4370 } 4371 uint32_t FindAndRemove(MethodNameAndSignatureComparator* comparator) 4372 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4373 const char* name = comparator->GetName(); 4374 uint32_t hash = ComputeModifiedUtf8Hash(name); 4375 size_t index = hash % hash_size_; 4376 while (true) { 4377 const uint32_t value = hash_table_[index]; 4378 // Since linear probe makes continuous blocks, hitting an invalid index means we are done 4379 // the block and can safely assume not found. 4380 if (value == invalid_index_) { 4381 break; 4382 } 4383 if (value != removed_index_) { // This signifies not already overriden. 4384 mirror::ArtMethod* virtual_method = 4385 klass_->GetVirtualMethodDuringLinking(value); 4386 if (comparator->HasSameNameAndSignature(virtual_method->GetInterfaceMethodIfProxy())) { 4387 hash_table_[index] = removed_index_; 4388 return value; 4389 } 4390 } 4391 if (++index == hash_size_) { 4392 index = 0; 4393 } 4394 } 4395 return GetNotFoundIndex(); 4396 } 4397 static uint32_t GetNotFoundIndex() { 4398 return invalid_index_; 4399 } 4400 4401 private: 4402 static const uint32_t invalid_index_; 4403 static const uint32_t removed_index_; 4404 4405 Handle<mirror::Class> klass_; 4406 const size_t hash_size_; 4407 uint32_t* const hash_table_; 4408}; 4409 4410const uint32_t LinkVirtualHashTable::invalid_index_ = std::numeric_limits<uint32_t>::max(); 4411const uint32_t LinkVirtualHashTable::removed_index_ = std::numeric_limits<uint32_t>::max() - 1; 4412 4413bool ClassLinker::LinkVirtualMethods(Thread* self, Handle<mirror::Class> klass) { 4414 const size_t num_virtual_methods = klass->NumVirtualMethods(); 4415 if (klass->HasSuperClass()) { 4416 const size_t super_vtable_length = klass->GetSuperClass()->GetVTableLength(); 4417 const size_t max_count = num_virtual_methods + super_vtable_length; 4418 StackHandleScope<2> hs(self); 4419 Handle<mirror::Class> super_class(hs.NewHandle(klass->GetSuperClass())); 4420 MutableHandle<mirror::ObjectArray<mirror::ArtMethod>> vtable; 4421 if (super_class->ShouldHaveEmbeddedImtAndVTable()) { 4422 vtable = hs.NewHandle(AllocArtMethodArray(self, max_count)); 4423 if (UNLIKELY(vtable.Get() == nullptr)) { 4424 CHECK(self->IsExceptionPending()); // OOME. 4425 return false; 4426 } 4427 for (size_t i = 0; i < super_vtable_length; i++) { 4428 vtable->SetWithoutChecks<false>(i, super_class->GetEmbeddedVTableEntry(i)); 4429 } 4430 if (num_virtual_methods == 0) { 4431 klass->SetVTable(vtable.Get()); 4432 return true; 4433 } 4434 } else { 4435 mirror::ObjectArray<mirror::ArtMethod>* super_vtable = super_class->GetVTable(); 4436 CHECK(super_vtable != nullptr) << PrettyClass(super_class.Get()); 4437 if (num_virtual_methods == 0) { 4438 klass->SetVTable(super_vtable); 4439 return true; 4440 } 4441 vtable = hs.NewHandle(super_vtable->CopyOf(self, max_count)); 4442 if (UNLIKELY(vtable.Get() == nullptr)) { 4443 CHECK(self->IsExceptionPending()); // OOME. 4444 return false; 4445 } 4446 } 4447 // How the algorithm works: 4448 // 1. Populate hash table by adding num_virtual_methods from klass. The values in the hash 4449 // table are: invalid_index for unused slots, index super_vtable_length + i for a virtual 4450 // method which has not been matched to a vtable method, and j if the virtual method at the 4451 // index overrode the super virtual method at index j. 4452 // 2. Loop through super virtual methods, if they overwrite, update hash table to j 4453 // (j < super_vtable_length) to avoid redundant checks. (TODO maybe use this info for reducing 4454 // the need for the initial vtable which we later shrink back down). 4455 // 3. Add non overridden methods to the end of the vtable. 4456 static constexpr size_t kMaxStackHash = 250; 4457 const size_t hash_table_size = num_virtual_methods * 3; 4458 uint32_t* hash_table_ptr; 4459 std::unique_ptr<uint32_t[]> hash_heap_storage; 4460 if (hash_table_size <= kMaxStackHash) { 4461 hash_table_ptr = reinterpret_cast<uint32_t*>( 4462 alloca(hash_table_size * sizeof(*hash_table_ptr))); 4463 } else { 4464 hash_heap_storage.reset(new uint32_t[hash_table_size]); 4465 hash_table_ptr = hash_heap_storage.get(); 4466 } 4467 LinkVirtualHashTable hash_table(klass, hash_table_size, hash_table_ptr); 4468 // Add virtual methods to the hash table. 4469 for (size_t i = 0; i < num_virtual_methods; ++i) { 4470 hash_table.Add(i); 4471 } 4472 // Loop through each super vtable method and see if they are overriden by a method we added to 4473 // the hash table. 4474 for (size_t j = 0; j < super_vtable_length; ++j) { 4475 // Search the hash table to see if we are overidden by any method. 4476 mirror::ArtMethod* super_method = vtable->GetWithoutChecks(j); 4477 MethodNameAndSignatureComparator super_method_name_comparator( 4478 super_method->GetInterfaceMethodIfProxy()); 4479 uint32_t hash_index = hash_table.FindAndRemove(&super_method_name_comparator); 4480 if (hash_index != hash_table.GetNotFoundIndex()) { 4481 mirror::ArtMethod* virtual_method = klass->GetVirtualMethodDuringLinking(hash_index); 4482 if (klass->CanAccessMember(super_method->GetDeclaringClass(), 4483 super_method->GetAccessFlags())) { 4484 if (super_method->IsFinal()) { 4485 ThrowLinkageError(klass.Get(), "Method %s overrides final method in class %s", 4486 PrettyMethod(virtual_method).c_str(), 4487 super_method->GetDeclaringClassDescriptor()); 4488 return false; 4489 } 4490 vtable->SetWithoutChecks<false>(j, virtual_method); 4491 virtual_method->SetMethodIndex(j); 4492 } else { 4493 LOG(WARNING) << "Before Android 4.1, method " << PrettyMethod(virtual_method) 4494 << " would have incorrectly overridden the package-private method in " 4495 << PrettyDescriptor(super_method->GetDeclaringClassDescriptor()); 4496 } 4497 } 4498 } 4499 // Add the non overridden methods at the end. 4500 size_t actual_count = super_vtable_length; 4501 for (size_t i = 0; i < num_virtual_methods; ++i) { 4502 mirror::ArtMethod* local_method = klass->GetVirtualMethodDuringLinking(i); 4503 size_t method_idx = local_method->GetMethodIndexDuringLinking(); 4504 if (method_idx < super_vtable_length && 4505 local_method == vtable->GetWithoutChecks(method_idx)) { 4506 continue; 4507 } 4508 vtable->SetWithoutChecks<false>(actual_count, local_method); 4509 local_method->SetMethodIndex(actual_count); 4510 ++actual_count; 4511 } 4512 if (!IsUint<16>(actual_count)) { 4513 ThrowClassFormatError(klass.Get(), "Too many methods defined on class: %zd", actual_count); 4514 return false; 4515 } 4516 // Shrink vtable if possible 4517 CHECK_LE(actual_count, max_count); 4518 if (actual_count < max_count) { 4519 vtable.Assign(vtable->CopyOf(self, actual_count)); 4520 if (UNLIKELY(vtable.Get() == nullptr)) { 4521 CHECK(self->IsExceptionPending()); // OOME. 4522 return false; 4523 } 4524 } 4525 klass->SetVTable(vtable.Get()); 4526 } else { 4527 CHECK_EQ(klass.Get(), GetClassRoot(kJavaLangObject)); 4528 if (!IsUint<16>(num_virtual_methods)) { 4529 ThrowClassFormatError(klass.Get(), "Too many methods: %d", 4530 static_cast<int>(num_virtual_methods)); 4531 return false; 4532 } 4533 mirror::ObjectArray<mirror::ArtMethod>* vtable = AllocArtMethodArray(self, num_virtual_methods); 4534 if (UNLIKELY(vtable == nullptr)) { 4535 CHECK(self->IsExceptionPending()); // OOME. 4536 return false; 4537 } 4538 for (size_t i = 0; i < num_virtual_methods; ++i) { 4539 mirror::ArtMethod* virtual_method = klass->GetVirtualMethodDuringLinking(i); 4540 vtable->SetWithoutChecks<false>(i, virtual_method); 4541 virtual_method->SetMethodIndex(i & 0xFFFF); 4542 } 4543 klass->SetVTable(vtable); 4544 } 4545 return true; 4546} 4547 4548bool ClassLinker::LinkInterfaceMethods(Thread* self, Handle<mirror::Class> klass, 4549 Handle<mirror::ObjectArray<mirror::Class>> interfaces, 4550 StackHandleScope<mirror::Class::kImtSize>* out_imt) { 4551 StackHandleScope<3> hs(self); 4552 Runtime* const runtime = Runtime::Current(); 4553 const bool has_superclass = klass->HasSuperClass(); 4554 const size_t super_ifcount = has_superclass ? klass->GetSuperClass()->GetIfTableCount() : 0U; 4555 const bool have_interfaces = interfaces.Get() != nullptr; 4556 const size_t num_interfaces = 4557 have_interfaces ? interfaces->GetLength() : klass->NumDirectInterfaces(); 4558 if (num_interfaces == 0) { 4559 if (super_ifcount == 0) { 4560 // Class implements no interfaces. 4561 DCHECK_EQ(klass->GetIfTableCount(), 0); 4562 DCHECK(klass->GetIfTable() == nullptr); 4563 return true; 4564 } 4565 // Class implements same interfaces as parent, are any of these not marker interfaces? 4566 bool has_non_marker_interface = false; 4567 mirror::IfTable* super_iftable = klass->GetSuperClass()->GetIfTable(); 4568 for (size_t i = 0; i < super_ifcount; ++i) { 4569 if (super_iftable->GetMethodArrayCount(i) > 0) { 4570 has_non_marker_interface = true; 4571 break; 4572 } 4573 } 4574 // Class just inherits marker interfaces from parent so recycle parent's iftable. 4575 if (!has_non_marker_interface) { 4576 klass->SetIfTable(super_iftable); 4577 return true; 4578 } 4579 } 4580 size_t ifcount = super_ifcount + num_interfaces; 4581 for (size_t i = 0; i < num_interfaces; i++) { 4582 mirror::Class* interface = have_interfaces ? 4583 interfaces->GetWithoutChecks(i) : mirror::Class::GetDirectInterface(self, klass, i); 4584 DCHECK(interface != nullptr); 4585 if (UNLIKELY(!interface->IsInterface())) { 4586 std::string temp; 4587 ThrowIncompatibleClassChangeError(klass.Get(), "Class %s implements non-interface class %s", 4588 PrettyDescriptor(klass.Get()).c_str(), 4589 PrettyDescriptor(interface->GetDescriptor(&temp)).c_str()); 4590 return false; 4591 } 4592 ifcount += interface->GetIfTableCount(); 4593 } 4594 MutableHandle<mirror::IfTable> iftable(hs.NewHandle(AllocIfTable(self, ifcount))); 4595 if (UNLIKELY(iftable.Get() == nullptr)) { 4596 CHECK(self->IsExceptionPending()); // OOME. 4597 return false; 4598 } 4599 if (super_ifcount != 0) { 4600 mirror::IfTable* super_iftable = klass->GetSuperClass()->GetIfTable(); 4601 for (size_t i = 0; i < super_ifcount; i++) { 4602 mirror::Class* super_interface = super_iftable->GetInterface(i); 4603 iftable->SetInterface(i, super_interface); 4604 } 4605 } 4606 self->AllowThreadSuspension(); 4607 // Flatten the interface inheritance hierarchy. 4608 size_t idx = super_ifcount; 4609 for (size_t i = 0; i < num_interfaces; i++) { 4610 mirror::Class* interface = have_interfaces ? interfaces->Get(i) : 4611 mirror::Class::GetDirectInterface(self, klass, i); 4612 // Check if interface is already in iftable 4613 bool duplicate = false; 4614 for (size_t j = 0; j < idx; j++) { 4615 mirror::Class* existing_interface = iftable->GetInterface(j); 4616 if (existing_interface == interface) { 4617 duplicate = true; 4618 break; 4619 } 4620 } 4621 if (!duplicate) { 4622 // Add this non-duplicate interface. 4623 iftable->SetInterface(idx++, interface); 4624 // Add this interface's non-duplicate super-interfaces. 4625 for (int32_t j = 0; j < interface->GetIfTableCount(); j++) { 4626 mirror::Class* super_interface = interface->GetIfTable()->GetInterface(j); 4627 bool super_duplicate = false; 4628 for (size_t k = 0; k < idx; k++) { 4629 mirror::Class* existing_interface = iftable->GetInterface(k); 4630 if (existing_interface == super_interface) { 4631 super_duplicate = true; 4632 break; 4633 } 4634 } 4635 if (!super_duplicate) { 4636 iftable->SetInterface(idx++, super_interface); 4637 } 4638 } 4639 } 4640 } 4641 self->AllowThreadSuspension(); 4642 // Shrink iftable in case duplicates were found 4643 if (idx < ifcount) { 4644 DCHECK_NE(num_interfaces, 0U); 4645 iftable.Assign(down_cast<mirror::IfTable*>(iftable->CopyOf(self, idx * mirror::IfTable::kMax))); 4646 if (UNLIKELY(iftable.Get() == nullptr)) { 4647 CHECK(self->IsExceptionPending()); // OOME. 4648 return false; 4649 } 4650 ifcount = idx; 4651 } else { 4652 DCHECK_EQ(idx, ifcount); 4653 } 4654 klass->SetIfTable(iftable.Get()); 4655 // If we're an interface, we don't need the vtable pointers, so we're done. 4656 if (klass->IsInterface()) { 4657 return true; 4658 } 4659 size_t miranda_list_size = 0; 4660 size_t max_miranda_methods = 0; // The max size of miranda_list. 4661 for (size_t i = 0; i < ifcount; ++i) { 4662 max_miranda_methods += iftable->GetInterface(i)->NumVirtualMethods(); 4663 } 4664 MutableHandle<mirror::ObjectArray<mirror::ArtMethod>> 4665 miranda_list(hs.NewHandle(AllocArtMethodArray(self, max_miranda_methods))); 4666 MutableHandle<mirror::ObjectArray<mirror::ArtMethod>> vtable( 4667 hs.NewHandle(klass->GetVTableDuringLinking())); 4668 // Copy the IMT from the super class if possible. 4669 bool extend_super_iftable = false; 4670 if (has_superclass) { 4671 mirror::Class* super_class = klass->GetSuperClass(); 4672 extend_super_iftable = true; 4673 if (super_class->ShouldHaveEmbeddedImtAndVTable()) { 4674 for (size_t i = 0; i < mirror::Class::kImtSize; ++i) { 4675 out_imt->SetReference(i, super_class->GetEmbeddedImTableEntry(i)); 4676 } 4677 } else { 4678 // No imt in the super class, need to reconstruct from the iftable. 4679 mirror::IfTable* if_table = super_class->GetIfTable(); 4680 mirror::ArtMethod* conflict_method = runtime->GetImtConflictMethod(); 4681 const size_t length = super_class->GetIfTableCount(); 4682 for (size_t i = 0; i < length; ++i) { 4683 mirror::Class* interface = iftable->GetInterface(i); 4684 const size_t num_virtuals = interface->NumVirtualMethods(); 4685 const size_t method_array_count = if_table->GetMethodArrayCount(i); 4686 DCHECK_EQ(num_virtuals, method_array_count); 4687 if (method_array_count == 0) { 4688 continue; 4689 } 4690 mirror::ObjectArray<mirror::ArtMethod>* method_array = if_table->GetMethodArray(i); 4691 for (size_t j = 0; j < num_virtuals; ++j) { 4692 mirror::ArtMethod* method = method_array->GetWithoutChecks(j); 4693 if (method->IsMiranda()) { 4694 continue; 4695 } 4696 mirror::ArtMethod* interface_method = interface->GetVirtualMethod(j); 4697 uint32_t imt_index = interface_method->GetDexMethodIndex() % mirror::Class::kImtSize; 4698 mirror::ArtMethod* imt_ref = out_imt->GetReference(imt_index)->AsArtMethod(); 4699 if (imt_ref == runtime->GetImtUnimplementedMethod()) { 4700 out_imt->SetReference(imt_index, method); 4701 } else if (imt_ref != conflict_method) { 4702 out_imt->SetReference(imt_index, conflict_method); 4703 } 4704 } 4705 } 4706 } 4707 } 4708 for (size_t i = 0; i < ifcount; ++i) { 4709 self->AllowThreadSuspension(); 4710 size_t num_methods = iftable->GetInterface(i)->NumVirtualMethods(); 4711 if (num_methods > 0) { 4712 StackHandleScope<2> hs2(self); 4713 const bool is_super = i < super_ifcount; 4714 const bool super_interface = is_super && extend_super_iftable; 4715 Handle<mirror::ObjectArray<mirror::ArtMethod>> method_array; 4716 Handle<mirror::ObjectArray<mirror::ArtMethod>> input_array; 4717 if (super_interface) { 4718 mirror::IfTable* if_table = klass->GetSuperClass()->GetIfTable(); 4719 DCHECK(if_table != nullptr); 4720 DCHECK(if_table->GetMethodArray(i) != nullptr); 4721 // If we are working on a super interface, try extending the existing method array. 4722 method_array = hs2.NewHandle(if_table->GetMethodArray(i)->Clone(self)-> 4723 AsObjectArray<mirror::ArtMethod>()); 4724 // We are overwriting a super class interface, try to only virtual methods instead of the 4725 // whole vtable. 4726 input_array = hs2.NewHandle(klass->GetVirtualMethods()); 4727 } else { 4728 method_array = hs2.NewHandle(AllocArtMethodArray(self, num_methods)); 4729 // A new interface, we need the whole vtable incase a new interface method is implemented 4730 // in the whole superclass. 4731 input_array = vtable; 4732 } 4733 if (UNLIKELY(method_array.Get() == nullptr)) { 4734 CHECK(self->IsExceptionPending()); // OOME. 4735 return false; 4736 } 4737 iftable->SetMethodArray(i, method_array.Get()); 4738 if (input_array.Get() == nullptr) { 4739 // If the added virtual methods is empty, do nothing. 4740 DCHECK(super_interface); 4741 continue; 4742 } 4743 for (size_t j = 0; j < num_methods; ++j) { 4744 mirror::ArtMethod* interface_method = iftable->GetInterface(i)->GetVirtualMethod(j); 4745 MethodNameAndSignatureComparator interface_name_comparator( 4746 interface_method->GetInterfaceMethodIfProxy()); 4747 int32_t k; 4748 // For each method listed in the interface's method list, find the 4749 // matching method in our class's method list. We want to favor the 4750 // subclass over the superclass, which just requires walking 4751 // back from the end of the vtable. (This only matters if the 4752 // superclass defines a private method and this class redefines 4753 // it -- otherwise it would use the same vtable slot. In .dex files 4754 // those don't end up in the virtual method table, so it shouldn't 4755 // matter which direction we go. We walk it backward anyway.) 4756 for (k = input_array->GetLength() - 1; k >= 0; --k) { 4757 mirror::ArtMethod* vtable_method = input_array->GetWithoutChecks(k); 4758 mirror::ArtMethod* vtable_method_for_name_comparison = 4759 vtable_method->GetInterfaceMethodIfProxy(); 4760 if (interface_name_comparator.HasSameNameAndSignature( 4761 vtable_method_for_name_comparison)) { 4762 if (!vtable_method->IsAbstract() && !vtable_method->IsPublic()) { 4763 ThrowIllegalAccessError( 4764 klass.Get(), 4765 "Method '%s' implementing interface method '%s' is not public", 4766 PrettyMethod(vtable_method).c_str(), 4767 PrettyMethod(interface_method).c_str()); 4768 return false; 4769 } 4770 method_array->SetWithoutChecks<false>(j, vtable_method); 4771 // Place method in imt if entry is empty, place conflict otherwise. 4772 uint32_t imt_index = interface_method->GetDexMethodIndex() % mirror::Class::kImtSize; 4773 mirror::ArtMethod* imt_ref = out_imt->GetReference(imt_index)->AsArtMethod(); 4774 mirror::ArtMethod* conflict_method = runtime->GetImtConflictMethod(); 4775 if (imt_ref == runtime->GetImtUnimplementedMethod()) { 4776 out_imt->SetReference(imt_index, vtable_method); 4777 } else if (imt_ref != conflict_method) { 4778 // If we are not a conflict and we have the same signature and name as the imt entry, 4779 // it must be that we overwrote a superclass vtable entry. 4780 MethodNameAndSignatureComparator imt_ref_name_comparator( 4781 imt_ref->GetInterfaceMethodIfProxy()); 4782 if (imt_ref_name_comparator.HasSameNameAndSignature( 4783 vtable_method_for_name_comparison)) { 4784 out_imt->SetReference(imt_index, vtable_method); 4785 } else { 4786 out_imt->SetReference(imt_index, conflict_method); 4787 } 4788 } 4789 break; 4790 } 4791 } 4792 if (k < 0 && !super_interface) { 4793 mirror::ArtMethod* miranda_method = nullptr; 4794 for (size_t l = 0; l < miranda_list_size; ++l) { 4795 mirror::ArtMethod* mir_method = miranda_list->Get(l); 4796 if (interface_name_comparator.HasSameNameAndSignature(mir_method)) { 4797 miranda_method = mir_method; 4798 break; 4799 } 4800 } 4801 if (miranda_method == nullptr) { 4802 // Point the interface table at a phantom slot. 4803 miranda_method = interface_method->Clone(self)->AsArtMethod(); 4804 if (UNLIKELY(miranda_method == nullptr)) { 4805 CHECK(self->IsExceptionPending()); // OOME. 4806 return false; 4807 } 4808 DCHECK_LT(miranda_list_size, max_miranda_methods); 4809 miranda_list->Set<false>(miranda_list_size++, miranda_method); 4810 } 4811 method_array->SetWithoutChecks<false>(j, miranda_method); 4812 } 4813 } 4814 } 4815 } 4816 if (miranda_list_size > 0) { 4817 int old_method_count = klass->NumVirtualMethods(); 4818 int new_method_count = old_method_count + miranda_list_size; 4819 mirror::ObjectArray<mirror::ArtMethod>* virtuals; 4820 if (old_method_count == 0) { 4821 virtuals = AllocArtMethodArray(self, new_method_count); 4822 } else { 4823 virtuals = klass->GetVirtualMethods()->CopyOf(self, new_method_count); 4824 } 4825 if (UNLIKELY(virtuals == nullptr)) { 4826 CHECK(self->IsExceptionPending()); // OOME. 4827 return false; 4828 } 4829 klass->SetVirtualMethods(virtuals); 4830 4831 int old_vtable_count = vtable->GetLength(); 4832 int new_vtable_count = old_vtable_count + miranda_list_size; 4833 vtable.Assign(vtable->CopyOf(self, new_vtable_count)); 4834 if (UNLIKELY(vtable.Get() == nullptr)) { 4835 CHECK(self->IsExceptionPending()); // OOME. 4836 return false; 4837 } 4838 for (size_t i = 0; i < miranda_list_size; ++i) { 4839 mirror::ArtMethod* method = miranda_list->Get(i); 4840 // Leave the declaring class alone as type indices are relative to it 4841 method->SetAccessFlags(method->GetAccessFlags() | kAccMiranda); 4842 method->SetMethodIndex(0xFFFF & (old_vtable_count + i)); 4843 klass->SetVirtualMethod(old_method_count + i, method); 4844 vtable->SetWithoutChecks<false>(old_vtable_count + i, method); 4845 } 4846 // TODO: do not assign to the vtable field until it is fully constructed. 4847 klass->SetVTable(vtable.Get()); 4848 } 4849 4850 if (kIsDebugBuild) { 4851 mirror::ObjectArray<mirror::ArtMethod>* check_vtable = klass->GetVTableDuringLinking(); 4852 for (int i = 0; i < check_vtable->GetLength(); ++i) { 4853 CHECK(check_vtable->GetWithoutChecks(i) != nullptr); 4854 } 4855 } 4856 4857 self->AllowThreadSuspension(); 4858 return true; 4859} 4860 4861bool ClassLinker::LinkInstanceFields(Thread* self, Handle<mirror::Class> klass) { 4862 CHECK(klass.Get() != nullptr); 4863 return LinkFields(self, klass, false, nullptr); 4864} 4865 4866bool ClassLinker::LinkStaticFields(Thread* self, Handle<mirror::Class> klass, size_t* class_size) { 4867 CHECK(klass.Get() != nullptr); 4868 return LinkFields(self, klass, true, class_size); 4869} 4870 4871struct LinkFieldsComparator { 4872 explicit LinkFieldsComparator() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4873 } 4874 // No thread safety analysis as will be called from STL. Checked lock held in constructor. 4875 bool operator()(ArtField* field1, ArtField* field2) 4876 NO_THREAD_SAFETY_ANALYSIS { 4877 // First come reference fields, then 64-bit, then 32-bit, and then 16-bit, then finally 8-bit. 4878 Primitive::Type type1 = field1->GetTypeAsPrimitiveType(); 4879 Primitive::Type type2 = field2->GetTypeAsPrimitiveType(); 4880 if (type1 != type2) { 4881 if (type1 == Primitive::kPrimNot) { 4882 // Reference always goes first. 4883 return true; 4884 } 4885 if (type2 == Primitive::kPrimNot) { 4886 // Reference always goes first. 4887 return false; 4888 } 4889 size_t size1 = Primitive::ComponentSize(type1); 4890 size_t size2 = Primitive::ComponentSize(type2); 4891 if (size1 != size2) { 4892 // Larger primitive types go first. 4893 return size1 > size2; 4894 } 4895 // Primitive types differ but sizes match. Arbitrarily order by primitive type. 4896 return type1 < type2; 4897 } 4898 // Same basic group? Then sort by dex field index. This is guaranteed to be sorted 4899 // by name and for equal names by type id index. 4900 // NOTE: This works also for proxies. Their static fields are assigned appropriate indexes. 4901 return field1->GetDexFieldIndex() < field2->GetDexFieldIndex(); 4902 } 4903}; 4904 4905bool ClassLinker::LinkFields(Thread* self, Handle<mirror::Class> klass, bool is_static, 4906 size_t* class_size) { 4907 self->AllowThreadSuspension(); 4908 const size_t num_fields = is_static ? klass->NumStaticFields() : klass->NumInstanceFields(); 4909 ArtField* const fields = is_static ? klass->GetSFields() : klass->GetIFields(); 4910 4911 // Initialize field_offset 4912 MemberOffset field_offset(0); 4913 if (is_static) { 4914 field_offset = klass->GetFirstReferenceStaticFieldOffsetDuringLinking(); 4915 } else { 4916 mirror::Class* super_class = klass->GetSuperClass(); 4917 if (super_class != nullptr) { 4918 CHECK(super_class->IsResolved()) 4919 << PrettyClass(klass.Get()) << " " << PrettyClass(super_class); 4920 field_offset = MemberOffset(super_class->GetObjectSize()); 4921 } 4922 } 4923 4924 CHECK_EQ(num_fields == 0, fields == nullptr) << PrettyClass(klass.Get()); 4925 4926 // we want a relatively stable order so that adding new fields 4927 // minimizes disruption of C++ version such as Class and Method. 4928 std::deque<ArtField*> grouped_and_sorted_fields; 4929 const char* old_no_suspend_cause = self->StartAssertNoThreadSuspension( 4930 "Naked ArtField references in deque"); 4931 for (size_t i = 0; i < num_fields; i++) { 4932 grouped_and_sorted_fields.push_back(&fields[i]); 4933 } 4934 std::sort(grouped_and_sorted_fields.begin(), grouped_and_sorted_fields.end(), 4935 LinkFieldsComparator()); 4936 4937 // References should be at the front. 4938 size_t current_field = 0; 4939 size_t num_reference_fields = 0; 4940 FieldGaps gaps; 4941 4942 for (; current_field < num_fields; current_field++) { 4943 ArtField* field = grouped_and_sorted_fields.front(); 4944 Primitive::Type type = field->GetTypeAsPrimitiveType(); 4945 bool isPrimitive = type != Primitive::kPrimNot; 4946 if (isPrimitive) { 4947 break; // past last reference, move on to the next phase 4948 } 4949 if (UNLIKELY(!IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>( 4950 field_offset.Uint32Value()))) { 4951 MemberOffset old_offset = field_offset; 4952 field_offset = MemberOffset(RoundUp(field_offset.Uint32Value(), 4)); 4953 AddFieldGap(old_offset.Uint32Value(), field_offset.Uint32Value(), &gaps); 4954 } 4955 DCHECK(IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>(field_offset.Uint32Value())); 4956 grouped_and_sorted_fields.pop_front(); 4957 num_reference_fields++; 4958 field->SetOffset(field_offset); 4959 field_offset = MemberOffset(field_offset.Uint32Value() + 4960 sizeof(mirror::HeapReference<mirror::Object>)); 4961 } 4962 // Gaps are stored as a max heap which means that we must shuffle from largest to smallest 4963 // otherwise we could end up with suboptimal gap fills. 4964 ShuffleForward<8>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 4965 ShuffleForward<4>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 4966 ShuffleForward<2>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 4967 ShuffleForward<1>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 4968 CHECK(grouped_and_sorted_fields.empty()) << "Missed " << grouped_and_sorted_fields.size() << 4969 " fields."; 4970 self->EndAssertNoThreadSuspension(old_no_suspend_cause); 4971 4972 // We lie to the GC about the java.lang.ref.Reference.referent field, so it doesn't scan it. 4973 if (!is_static && klass->DescriptorEquals("Ljava/lang/ref/Reference;")) { 4974 // We know there are no non-reference fields in the Reference classes, and we know 4975 // that 'referent' is alphabetically last, so this is easy... 4976 CHECK_EQ(num_reference_fields, num_fields) << PrettyClass(klass.Get()); 4977 CHECK_STREQ(fields[num_fields - 1].GetName(), "referent") << PrettyClass(klass.Get()); 4978 --num_reference_fields; 4979 } 4980 4981 size_t size = field_offset.Uint32Value(); 4982 // Update klass 4983 if (is_static) { 4984 klass->SetNumReferenceStaticFields(num_reference_fields); 4985 *class_size = size; 4986 } else { 4987 klass->SetNumReferenceInstanceFields(num_reference_fields); 4988 if (!klass->IsVariableSize()) { 4989 if (klass->DescriptorEquals("Ljava/lang/reflect/ArtMethod;")) { 4990 size_t pointer_size = GetInstructionSetPointerSize(Runtime::Current()->GetInstructionSet()); 4991 klass->SetObjectSize(mirror::ArtMethod::InstanceSize(pointer_size)); 4992 } else { 4993 std::string temp; 4994 DCHECK_GE(size, sizeof(mirror::Object)) << klass->GetDescriptor(&temp); 4995 size_t previous_size = klass->GetObjectSize(); 4996 if (previous_size != 0) { 4997 // Make sure that we didn't originally have an incorrect size. 4998 CHECK_EQ(previous_size, size) << klass->GetDescriptor(&temp); 4999 } 5000 klass->SetObjectSize(size); 5001 } 5002 } 5003 } 5004 5005 if (kIsDebugBuild) { 5006 // Make sure that the fields array is ordered by name but all reference 5007 // offsets are at the beginning as far as alignment allows. 5008 MemberOffset start_ref_offset = is_static 5009 ? klass->GetFirstReferenceStaticFieldOffsetDuringLinking() 5010 : klass->GetFirstReferenceInstanceFieldOffset(); 5011 MemberOffset end_ref_offset(start_ref_offset.Uint32Value() + 5012 num_reference_fields * 5013 sizeof(mirror::HeapReference<mirror::Object>)); 5014 MemberOffset current_ref_offset = start_ref_offset; 5015 for (size_t i = 0; i < num_fields; i++) { 5016 ArtField* field = &fields[i]; 5017 VLOG(class_linker) << "LinkFields: " << (is_static ? "static" : "instance") 5018 << " class=" << PrettyClass(klass.Get()) << " field=" << PrettyField(field) << " offset=" 5019 << field->GetOffset(); 5020 if (i != 0) { 5021 ArtField* const prev_field = &fields[i - 1]; 5022 // NOTE: The field names can be the same. This is not possible in the Java language 5023 // but it's valid Java/dex bytecode and for example proguard can generate such bytecode. 5024 CHECK_LE(strcmp(prev_field->GetName(), field->GetName()), 0); 5025 } 5026 Primitive::Type type = field->GetTypeAsPrimitiveType(); 5027 bool is_primitive = type != Primitive::kPrimNot; 5028 if (klass->DescriptorEquals("Ljava/lang/ref/Reference;") && 5029 strcmp("referent", field->GetName()) == 0) { 5030 is_primitive = true; // We lied above, so we have to expect a lie here. 5031 } 5032 MemberOffset offset = field->GetOffsetDuringLinking(); 5033 if (is_primitive) { 5034 if (offset.Uint32Value() < end_ref_offset.Uint32Value()) { 5035 // Shuffled before references. 5036 size_t type_size = Primitive::ComponentSize(type); 5037 CHECK_LT(type_size, sizeof(mirror::HeapReference<mirror::Object>)); 5038 CHECK_LT(offset.Uint32Value(), start_ref_offset.Uint32Value()); 5039 CHECK_LE(offset.Uint32Value() + type_size, start_ref_offset.Uint32Value()); 5040 CHECK(!IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>(offset.Uint32Value())); 5041 } 5042 } else { 5043 CHECK_EQ(current_ref_offset.Uint32Value(), offset.Uint32Value()); 5044 current_ref_offset = MemberOffset(current_ref_offset.Uint32Value() + 5045 sizeof(mirror::HeapReference<mirror::Object>)); 5046 } 5047 } 5048 CHECK_EQ(current_ref_offset.Uint32Value(), end_ref_offset.Uint32Value()); 5049 } 5050 return true; 5051} 5052 5053// Set the bitmap of reference instance field offsets. 5054void ClassLinker::CreateReferenceInstanceOffsets(Handle<mirror::Class> klass) { 5055 uint32_t reference_offsets = 0; 5056 mirror::Class* super_class = klass->GetSuperClass(); 5057 // Leave the reference offsets as 0 for mirror::Object (the class field is handled specially). 5058 if (super_class != nullptr) { 5059 reference_offsets = super_class->GetReferenceInstanceOffsets(); 5060 // Compute reference offsets unless our superclass overflowed. 5061 if (reference_offsets != mirror::Class::kClassWalkSuper) { 5062 size_t num_reference_fields = klass->NumReferenceInstanceFieldsDuringLinking(); 5063 if (num_reference_fields != 0u) { 5064 // All of the fields that contain object references are guaranteed be grouped in memory 5065 // starting at an appropriately aligned address after super class object data. 5066 uint32_t start_offset = RoundUp(super_class->GetObjectSize(), 5067 sizeof(mirror::HeapReference<mirror::Object>)); 5068 uint32_t start_bit = (start_offset - mirror::kObjectHeaderSize) / 5069 sizeof(mirror::HeapReference<mirror::Object>); 5070 if (start_bit + num_reference_fields > 32) { 5071 reference_offsets = mirror::Class::kClassWalkSuper; 5072 } else { 5073 reference_offsets |= (0xffffffffu << start_bit) & 5074 (0xffffffffu >> (32 - (start_bit + num_reference_fields))); 5075 } 5076 } 5077 } 5078 } 5079 klass->SetReferenceInstanceOffsets(reference_offsets); 5080} 5081 5082mirror::String* ClassLinker::ResolveString(const DexFile& dex_file, uint32_t string_idx, 5083 Handle<mirror::DexCache> dex_cache) { 5084 DCHECK(dex_cache.Get() != nullptr); 5085 mirror::String* resolved = dex_cache->GetResolvedString(string_idx); 5086 if (resolved != nullptr) { 5087 return resolved; 5088 } 5089 uint32_t utf16_length; 5090 const char* utf8_data = dex_file.StringDataAndUtf16LengthByIdx(string_idx, &utf16_length); 5091 mirror::String* string = intern_table_->InternStrong(utf16_length, utf8_data); 5092 dex_cache->SetResolvedString(string_idx, string); 5093 return string; 5094} 5095 5096mirror::Class* ClassLinker::ResolveType(const DexFile& dex_file, uint16_t type_idx, 5097 mirror::Class* referrer) { 5098 StackHandleScope<2> hs(Thread::Current()); 5099 Handle<mirror::DexCache> dex_cache(hs.NewHandle(referrer->GetDexCache())); 5100 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(referrer->GetClassLoader())); 5101 return ResolveType(dex_file, type_idx, dex_cache, class_loader); 5102} 5103 5104mirror::Class* ClassLinker::ResolveType(const DexFile& dex_file, uint16_t type_idx, 5105 Handle<mirror::DexCache> dex_cache, 5106 Handle<mirror::ClassLoader> class_loader) { 5107 DCHECK(dex_cache.Get() != nullptr); 5108 mirror::Class* resolved = dex_cache->GetResolvedType(type_idx); 5109 if (resolved == nullptr) { 5110 Thread* self = Thread::Current(); 5111 const char* descriptor = dex_file.StringByTypeIdx(type_idx); 5112 resolved = FindClass(self, descriptor, class_loader); 5113 if (resolved != nullptr) { 5114 // TODO: we used to throw here if resolved's class loader was not the 5115 // boot class loader. This was to permit different classes with the 5116 // same name to be loaded simultaneously by different loaders 5117 dex_cache->SetResolvedType(type_idx, resolved); 5118 } else { 5119 CHECK(self->IsExceptionPending()) 5120 << "Expected pending exception for failed resolution of: " << descriptor; 5121 // Convert a ClassNotFoundException to a NoClassDefFoundError. 5122 StackHandleScope<1> hs(self); 5123 Handle<mirror::Throwable> cause(hs.NewHandle(self->GetException())); 5124 if (cause->InstanceOf(GetClassRoot(kJavaLangClassNotFoundException))) { 5125 DCHECK(resolved == nullptr); // No Handle needed to preserve resolved. 5126 self->ClearException(); 5127 ThrowNoClassDefFoundError("Failed resolution of: %s", descriptor); 5128 self->GetException()->SetCause(cause.Get()); 5129 } 5130 } 5131 } 5132 DCHECK((resolved == nullptr) || resolved->IsResolved() || resolved->IsErroneous()) 5133 << PrettyDescriptor(resolved) << " " << resolved->GetStatus(); 5134 return resolved; 5135} 5136 5137mirror::ArtMethod* ClassLinker::ResolveMethod(const DexFile& dex_file, uint32_t method_idx, 5138 Handle<mirror::DexCache> dex_cache, 5139 Handle<mirror::ClassLoader> class_loader, 5140 Handle<mirror::ArtMethod> referrer, 5141 InvokeType type) { 5142 DCHECK(dex_cache.Get() != nullptr); 5143 // Check for hit in the dex cache. 5144 mirror::ArtMethod* resolved = dex_cache->GetResolvedMethod(method_idx); 5145 if (resolved != nullptr && !resolved->IsRuntimeMethod()) { 5146 return resolved; 5147 } 5148 // Fail, get the declaring class. 5149 const DexFile::MethodId& method_id = dex_file.GetMethodId(method_idx); 5150 mirror::Class* klass = ResolveType(dex_file, method_id.class_idx_, dex_cache, class_loader); 5151 if (klass == nullptr) { 5152 DCHECK(Thread::Current()->IsExceptionPending()); 5153 return nullptr; 5154 } 5155 // Scan using method_idx, this saves string compares but will only hit for matching dex 5156 // caches/files. 5157 switch (type) { 5158 case kDirect: // Fall-through. 5159 case kStatic: 5160 resolved = klass->FindDirectMethod(dex_cache.Get(), method_idx); 5161 break; 5162 case kInterface: 5163 resolved = klass->FindInterfaceMethod(dex_cache.Get(), method_idx); 5164 DCHECK(resolved == nullptr || resolved->GetDeclaringClass()->IsInterface()); 5165 break; 5166 case kSuper: // Fall-through. 5167 case kVirtual: 5168 resolved = klass->FindVirtualMethod(dex_cache.Get(), method_idx); 5169 break; 5170 default: 5171 LOG(FATAL) << "Unreachable - invocation type: " << type; 5172 UNREACHABLE(); 5173 } 5174 if (resolved == nullptr) { 5175 // Search by name, which works across dex files. 5176 const char* name = dex_file.StringDataByIdx(method_id.name_idx_); 5177 const Signature signature = dex_file.GetMethodSignature(method_id); 5178 switch (type) { 5179 case kDirect: // Fall-through. 5180 case kStatic: 5181 resolved = klass->FindDirectMethod(name, signature); 5182 break; 5183 case kInterface: 5184 resolved = klass->FindInterfaceMethod(name, signature); 5185 DCHECK(resolved == nullptr || resolved->GetDeclaringClass()->IsInterface()); 5186 break; 5187 case kSuper: // Fall-through. 5188 case kVirtual: 5189 resolved = klass->FindVirtualMethod(name, signature); 5190 break; 5191 } 5192 } 5193 // If we found a method, check for incompatible class changes. 5194 if (LIKELY(resolved != nullptr && !resolved->CheckIncompatibleClassChange(type))) { 5195 // Be a good citizen and update the dex cache to speed subsequent calls. 5196 dex_cache->SetResolvedMethod(method_idx, resolved); 5197 return resolved; 5198 } else { 5199 // If we had a method, it's an incompatible-class-change error. 5200 if (resolved != nullptr) { 5201 ThrowIncompatibleClassChangeError(type, resolved->GetInvokeType(), resolved, referrer.Get()); 5202 } else { 5203 // We failed to find the method which means either an access error, an incompatible class 5204 // change, or no such method. First try to find the method among direct and virtual methods. 5205 const char* name = dex_file.StringDataByIdx(method_id.name_idx_); 5206 const Signature signature = dex_file.GetMethodSignature(method_id); 5207 switch (type) { 5208 case kDirect: 5209 case kStatic: 5210 resolved = klass->FindVirtualMethod(name, signature); 5211 // Note: kDirect and kStatic are also mutually exclusive, but in that case we would 5212 // have had a resolved method before, which triggers the "true" branch above. 5213 break; 5214 case kInterface: 5215 case kVirtual: 5216 case kSuper: 5217 resolved = klass->FindDirectMethod(name, signature); 5218 break; 5219 } 5220 5221 // If we found something, check that it can be accessed by the referrer. 5222 bool exception_generated = false; 5223 if (resolved != nullptr && referrer.Get() != nullptr) { 5224 mirror::Class* methods_class = resolved->GetDeclaringClass(); 5225 mirror::Class* referring_class = referrer->GetDeclaringClass(); 5226 if (!referring_class->CanAccess(methods_class)) { 5227 ThrowIllegalAccessErrorClassForMethodDispatch(referring_class, methods_class, 5228 resolved, type); 5229 exception_generated = true; 5230 } else if (!referring_class->CanAccessMember(methods_class, 5231 resolved->GetAccessFlags())) { 5232 ThrowIllegalAccessErrorMethod(referring_class, resolved); 5233 exception_generated = true; 5234 } 5235 } 5236 if (!exception_generated) { 5237 // Otherwise, throw an IncompatibleClassChangeError if we found something, and check 5238 // interface methods and throw if we find the method there. If we find nothing, throw a 5239 // NoSuchMethodError. 5240 switch (type) { 5241 case kDirect: 5242 case kStatic: 5243 if (resolved != nullptr) { 5244 ThrowIncompatibleClassChangeError(type, kVirtual, resolved, referrer.Get()); 5245 } else { 5246 resolved = klass->FindInterfaceMethod(name, signature); 5247 if (resolved != nullptr) { 5248 ThrowIncompatibleClassChangeError(type, kInterface, resolved, referrer.Get()); 5249 } else { 5250 ThrowNoSuchMethodError(type, klass, name, signature); 5251 } 5252 } 5253 break; 5254 case kInterface: 5255 if (resolved != nullptr) { 5256 ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer.Get()); 5257 } else { 5258 resolved = klass->FindVirtualMethod(name, signature); 5259 if (resolved != nullptr) { 5260 ThrowIncompatibleClassChangeError(type, kVirtual, resolved, referrer.Get()); 5261 } else { 5262 ThrowNoSuchMethodError(type, klass, name, signature); 5263 } 5264 } 5265 break; 5266 case kSuper: 5267 if (resolved != nullptr) { 5268 ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer.Get()); 5269 } else { 5270 ThrowNoSuchMethodError(type, klass, name, signature); 5271 } 5272 break; 5273 case kVirtual: 5274 if (resolved != nullptr) { 5275 ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer.Get()); 5276 } else { 5277 resolved = klass->FindInterfaceMethod(name, signature); 5278 if (resolved != nullptr) { 5279 ThrowIncompatibleClassChangeError(type, kInterface, resolved, referrer.Get()); 5280 } else { 5281 ThrowNoSuchMethodError(type, klass, name, signature); 5282 } 5283 } 5284 break; 5285 } 5286 } 5287 } 5288 Thread::Current()->AssertPendingException(); 5289 return nullptr; 5290 } 5291} 5292 5293ArtField* ClassLinker::ResolveField(const DexFile& dex_file, uint32_t field_idx, 5294 Handle<mirror::DexCache> dex_cache, 5295 Handle<mirror::ClassLoader> class_loader, bool is_static) { 5296 DCHECK(dex_cache.Get() != nullptr); 5297 ArtField* resolved = dex_cache->GetResolvedField(field_idx, image_pointer_size_); 5298 if (resolved != nullptr) { 5299 return resolved; 5300 } 5301 const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx); 5302 Thread* const self = Thread::Current(); 5303 StackHandleScope<1> hs(self); 5304 Handle<mirror::Class> klass( 5305 hs.NewHandle(ResolveType(dex_file, field_id.class_idx_, dex_cache, class_loader))); 5306 if (klass.Get() == nullptr) { 5307 DCHECK(Thread::Current()->IsExceptionPending()); 5308 return nullptr; 5309 } 5310 5311 if (is_static) { 5312 resolved = mirror::Class::FindStaticField(self, klass, dex_cache.Get(), field_idx); 5313 } else { 5314 resolved = klass->FindInstanceField(dex_cache.Get(), field_idx); 5315 } 5316 5317 if (resolved == nullptr) { 5318 const char* name = dex_file.GetFieldName(field_id); 5319 const char* type = dex_file.GetFieldTypeDescriptor(field_id); 5320 if (is_static) { 5321 resolved = mirror::Class::FindStaticField(self, klass, name, type); 5322 } else { 5323 resolved = klass->FindInstanceField(name, type); 5324 } 5325 if (resolved == nullptr) { 5326 ThrowNoSuchFieldError(is_static ? "static " : "instance ", klass.Get(), type, name); 5327 return nullptr; 5328 } 5329 } 5330 dex_cache->SetResolvedField(field_idx, resolved, image_pointer_size_); 5331 return resolved; 5332} 5333 5334ArtField* ClassLinker::ResolveFieldJLS(const DexFile& dex_file, uint32_t field_idx, 5335 Handle<mirror::DexCache> dex_cache, 5336 Handle<mirror::ClassLoader> class_loader) { 5337 DCHECK(dex_cache.Get() != nullptr); 5338 ArtField* resolved = dex_cache->GetResolvedField(field_idx, image_pointer_size_); 5339 if (resolved != nullptr) { 5340 return resolved; 5341 } 5342 const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx); 5343 Thread* self = Thread::Current(); 5344 StackHandleScope<1> hs(self); 5345 Handle<mirror::Class> klass( 5346 hs.NewHandle(ResolveType(dex_file, field_id.class_idx_, dex_cache, class_loader))); 5347 if (klass.Get() == nullptr) { 5348 DCHECK(Thread::Current()->IsExceptionPending()); 5349 return nullptr; 5350 } 5351 5352 StringPiece name(dex_file.StringDataByIdx(field_id.name_idx_)); 5353 StringPiece type(dex_file.StringDataByIdx( 5354 dex_file.GetTypeId(field_id.type_idx_).descriptor_idx_)); 5355 resolved = mirror::Class::FindField(self, klass, name, type); 5356 if (resolved != nullptr) { 5357 dex_cache->SetResolvedField(field_idx, resolved, image_pointer_size_); 5358 } else { 5359 ThrowNoSuchFieldError("", klass.Get(), type, name); 5360 } 5361 return resolved; 5362} 5363 5364const char* ClassLinker::MethodShorty(uint32_t method_idx, mirror::ArtMethod* referrer, 5365 uint32_t* length) { 5366 mirror::Class* declaring_class = referrer->GetDeclaringClass(); 5367 mirror::DexCache* dex_cache = declaring_class->GetDexCache(); 5368 const DexFile& dex_file = *dex_cache->GetDexFile(); 5369 const DexFile::MethodId& method_id = dex_file.GetMethodId(method_idx); 5370 return dex_file.GetMethodShorty(method_id, length); 5371} 5372 5373void ClassLinker::DumpAllClasses(int flags) { 5374 if (dex_cache_image_class_lookup_required_) { 5375 MoveImageClassesToClassTable(); 5376 } 5377 // TODO: at the time this was written, it wasn't safe to call PrettyField with the ClassLinker 5378 // lock held, because it might need to resolve a field's type, which would try to take the lock. 5379 std::vector<mirror::Class*> all_classes; 5380 { 5381 ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 5382 for (GcRoot<mirror::Class>& it : class_table_) { 5383 all_classes.push_back(it.Read()); 5384 } 5385 } 5386 5387 for (size_t i = 0; i < all_classes.size(); ++i) { 5388 all_classes[i]->DumpClass(std::cerr, flags); 5389 } 5390} 5391 5392static OatFile::OatMethod CreateOatMethod(const void* code) { 5393 CHECK(code != nullptr); 5394 const uint8_t* base = reinterpret_cast<const uint8_t*>(code); // Base of data points at code. 5395 base -= sizeof(void*); // Move backward so that code_offset != 0. 5396 const uint32_t code_offset = sizeof(void*); 5397 return OatFile::OatMethod(base, code_offset); 5398} 5399 5400bool ClassLinker::IsQuickResolutionStub(const void* entry_point) const { 5401 return (entry_point == GetQuickResolutionStub()) || 5402 (quick_resolution_trampoline_ == entry_point); 5403} 5404 5405bool ClassLinker::IsQuickToInterpreterBridge(const void* entry_point) const { 5406 return (entry_point == GetQuickToInterpreterBridge()) || 5407 (quick_to_interpreter_bridge_trampoline_ == entry_point); 5408} 5409 5410bool ClassLinker::IsQuickGenericJniStub(const void* entry_point) const { 5411 return (entry_point == GetQuickGenericJniStub()) || 5412 (quick_generic_jni_trampoline_ == entry_point); 5413} 5414 5415const void* ClassLinker::GetRuntimeQuickGenericJniStub() const { 5416 return GetQuickGenericJniStub(); 5417} 5418 5419void ClassLinker::SetEntryPointsToCompiledCode(mirror::ArtMethod* method, 5420 const void* method_code) const { 5421 OatFile::OatMethod oat_method = CreateOatMethod(method_code); 5422 oat_method.LinkMethod(method); 5423 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 5424} 5425 5426void ClassLinker::SetEntryPointsToInterpreter(mirror::ArtMethod* method) const { 5427 if (!method->IsNative()) { 5428 method->SetEntryPointFromInterpreter(artInterpreterToInterpreterBridge); 5429 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge()); 5430 } else { 5431 const void* quick_method_code = GetQuickGenericJniStub(); 5432 OatFile::OatMethod oat_method = CreateOatMethod(quick_method_code); 5433 oat_method.LinkMethod(method); 5434 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 5435 } 5436} 5437 5438void ClassLinker::DumpForSigQuit(std::ostream& os) { 5439 Thread* self = Thread::Current(); 5440 if (dex_cache_image_class_lookup_required_) { 5441 ScopedObjectAccess soa(self); 5442 MoveImageClassesToClassTable(); 5443 } 5444 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 5445 os << "Zygote loaded classes=" << pre_zygote_class_table_.Size() << " post zygote classes=" 5446 << class_table_.Size() << "\n"; 5447} 5448 5449size_t ClassLinker::NumLoadedClasses() { 5450 if (dex_cache_image_class_lookup_required_) { 5451 MoveImageClassesToClassTable(); 5452 } 5453 ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 5454 // Only return non zygote classes since these are the ones which apps which care about. 5455 return class_table_.Size(); 5456} 5457 5458pid_t ClassLinker::GetClassesLockOwner() { 5459 return Locks::classlinker_classes_lock_->GetExclusiveOwnerTid(); 5460} 5461 5462pid_t ClassLinker::GetDexLockOwner() { 5463 return dex_lock_.GetExclusiveOwnerTid(); 5464} 5465 5466void ClassLinker::SetClassRoot(ClassRoot class_root, mirror::Class* klass) { 5467 DCHECK(!init_done_); 5468 5469 DCHECK(klass != nullptr); 5470 DCHECK(klass->GetClassLoader() == nullptr); 5471 5472 mirror::ObjectArray<mirror::Class>* class_roots = class_roots_.Read(); 5473 DCHECK(class_roots != nullptr); 5474 DCHECK(class_roots->Get(class_root) == nullptr); 5475 class_roots->Set<false>(class_root, klass); 5476} 5477 5478const char* ClassLinker::GetClassRootDescriptor(ClassRoot class_root) { 5479 static const char* class_roots_descriptors[] = { 5480 "Ljava/lang/Class;", 5481 "Ljava/lang/Object;", 5482 "[Ljava/lang/Class;", 5483 "[Ljava/lang/Object;", 5484 "Ljava/lang/String;", 5485 "Ljava/lang/DexCache;", 5486 "Ljava/lang/ref/Reference;", 5487 "Ljava/lang/reflect/ArtMethod;", 5488 "Ljava/lang/reflect/Constructor;", 5489 "Ljava/lang/reflect/Field;", 5490 "Ljava/lang/reflect/Method;", 5491 "Ljava/lang/reflect/Proxy;", 5492 "[Ljava/lang/String;", 5493 "[Ljava/lang/reflect/ArtMethod;", 5494 "[Ljava/lang/reflect/Constructor;", 5495 "[Ljava/lang/reflect/Field;", 5496 "[Ljava/lang/reflect/Method;", 5497 "Ljava/lang/ClassLoader;", 5498 "Ljava/lang/Throwable;", 5499 "Ljava/lang/ClassNotFoundException;", 5500 "Ljava/lang/StackTraceElement;", 5501 "Z", 5502 "B", 5503 "C", 5504 "D", 5505 "F", 5506 "I", 5507 "J", 5508 "S", 5509 "V", 5510 "[Z", 5511 "[B", 5512 "[C", 5513 "[D", 5514 "[F", 5515 "[I", 5516 "[J", 5517 "[S", 5518 "[Ljava/lang/StackTraceElement;", 5519 }; 5520 static_assert(arraysize(class_roots_descriptors) == size_t(kClassRootsMax), 5521 "Mismatch between class descriptors and class-root enum"); 5522 5523 const char* descriptor = class_roots_descriptors[class_root]; 5524 CHECK(descriptor != nullptr); 5525 return descriptor; 5526} 5527 5528std::size_t ClassLinker::ClassDescriptorHashEquals::operator()(const GcRoot<mirror::Class>& root) 5529 const { 5530 std::string temp; 5531 return ComputeModifiedUtf8Hash(root.Read()->GetDescriptor(&temp)); 5532} 5533 5534bool ClassLinker::ClassDescriptorHashEquals::operator()(const GcRoot<mirror::Class>& a, 5535 const GcRoot<mirror::Class>& b) const { 5536 if (a.Read()->GetClassLoader() != b.Read()->GetClassLoader()) { 5537 return false; 5538 } 5539 std::string temp; 5540 return a.Read()->DescriptorEquals(b.Read()->GetDescriptor(&temp)); 5541} 5542 5543std::size_t ClassLinker::ClassDescriptorHashEquals::operator()( 5544 const std::pair<const char*, mirror::ClassLoader*>& element) const { 5545 return ComputeModifiedUtf8Hash(element.first); 5546} 5547 5548bool ClassLinker::ClassDescriptorHashEquals::operator()( 5549 const GcRoot<mirror::Class>& a, const std::pair<const char*, mirror::ClassLoader*>& b) const { 5550 if (a.Read()->GetClassLoader() != b.second) { 5551 return false; 5552 } 5553 return a.Read()->DescriptorEquals(b.first); 5554} 5555 5556bool ClassLinker::ClassDescriptorHashEquals::operator()(const GcRoot<mirror::Class>& a, 5557 const char* descriptor) const { 5558 return a.Read()->DescriptorEquals(descriptor); 5559} 5560 5561std::size_t ClassLinker::ClassDescriptorHashEquals::operator()(const char* descriptor) const { 5562 return ComputeModifiedUtf8Hash(descriptor); 5563} 5564 5565bool ClassLinker::MayBeCalledWithDirectCodePointer(mirror::ArtMethod* m) { 5566 if (Runtime::Current()->UseJit()) { 5567 // JIT can have direct code pointers from any method to any other method. 5568 return true; 5569 } 5570 // Non-image methods don't use direct code pointer. 5571 if (!m->GetDeclaringClass()->IsBootStrapClassLoaded()) { 5572 return false; 5573 } 5574 if (m->IsPrivate()) { 5575 // The method can only be called inside its own oat file. Therefore it won't be called using 5576 // its direct code if the oat file has been compiled in PIC mode. 5577 const DexFile& dex_file = m->GetDeclaringClass()->GetDexFile(); 5578 const OatFile::OatDexFile* oat_dex_file = dex_file.GetOatDexFile(); 5579 if (oat_dex_file == nullptr) { 5580 // No oat file: the method has not been compiled. 5581 return false; 5582 } 5583 const OatFile* oat_file = oat_dex_file->GetOatFile(); 5584 return oat_file != nullptr && !oat_file->IsPic(); 5585 } else { 5586 // The method can be called outside its own oat file. Therefore it won't be called using its 5587 // direct code pointer only if all loaded oat files have been compiled in PIC mode. 5588 ReaderMutexLock mu(Thread::Current(), dex_lock_); 5589 for (const OatFile* oat_file : oat_files_) { 5590 if (!oat_file->IsPic()) { 5591 return true; 5592 } 5593 } 5594 return false; 5595 } 5596} 5597 5598jobject ClassLinker::CreatePathClassLoader(Thread* self, std::vector<const DexFile*>& dex_files) { 5599 // SOAAlreadyRunnable is protected, and we need something to add a global reference. 5600 // We could move the jobject to the callers, but all call-sites do this... 5601 ScopedObjectAccessUnchecked soa(self); 5602 5603 // Register the dex files. 5604 for (const DexFile* dex_file : dex_files) { 5605 RegisterDexFile(*dex_file); 5606 } 5607 5608 // For now, create a libcore-level DexFile for each ART DexFile. This "explodes" multidex. 5609 StackHandleScope<10> hs(self); 5610 5611 ArtField* dex_elements_field = 5612 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList_dexElements); 5613 5614 mirror::Class* dex_elements_class = dex_elements_field->GetType<true>(); 5615 DCHECK(dex_elements_class != nullptr); 5616 DCHECK(dex_elements_class->IsArrayClass()); 5617 Handle<mirror::ObjectArray<mirror::Object>> h_dex_elements(hs.NewHandle( 5618 mirror::ObjectArray<mirror::Object>::Alloc(self, dex_elements_class, dex_files.size()))); 5619 Handle<mirror::Class> h_dex_element_class = 5620 hs.NewHandle(dex_elements_class->GetComponentType()); 5621 5622 ArtField* element_file_field = 5623 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList__Element_dexFile); 5624 DCHECK_EQ(h_dex_element_class.Get(), element_file_field->GetDeclaringClass()); 5625 5626 ArtField* cookie_field = soa.DecodeField(WellKnownClasses::dalvik_system_DexFile_cookie); 5627 DCHECK_EQ(cookie_field->GetDeclaringClass(), element_file_field->GetType<false>()); 5628 5629 // Fill the elements array. 5630 int32_t index = 0; 5631 for (const DexFile* dex_file : dex_files) { 5632 StackHandleScope<3> hs2(self); 5633 5634 Handle<mirror::LongArray> h_long_array = hs2.NewHandle(mirror::LongArray::Alloc(self, 1)); 5635 DCHECK(h_long_array.Get() != nullptr); 5636 h_long_array->Set(0, reinterpret_cast<intptr_t>(dex_file)); 5637 5638 Handle<mirror::Object> h_dex_file = hs2.NewHandle( 5639 cookie_field->GetDeclaringClass()->AllocObject(self)); 5640 DCHECK(h_dex_file.Get() != nullptr); 5641 cookie_field->SetObject<false>(h_dex_file.Get(), h_long_array.Get()); 5642 5643 Handle<mirror::Object> h_element = hs2.NewHandle(h_dex_element_class->AllocObject(self)); 5644 DCHECK(h_element.Get() != nullptr); 5645 element_file_field->SetObject<false>(h_element.Get(), h_dex_file.Get()); 5646 5647 h_dex_elements->Set(index, h_element.Get()); 5648 index++; 5649 } 5650 DCHECK_EQ(index, h_dex_elements->GetLength()); 5651 5652 // Create DexPathList. 5653 Handle<mirror::Object> h_dex_path_list = hs.NewHandle( 5654 dex_elements_field->GetDeclaringClass()->AllocObject(self)); 5655 DCHECK(h_dex_path_list.Get() != nullptr); 5656 // Set elements. 5657 dex_elements_field->SetObject<false>(h_dex_path_list.Get(), h_dex_elements.Get()); 5658 5659 // Create PathClassLoader. 5660 Handle<mirror::Class> h_path_class_class = hs.NewHandle( 5661 soa.Decode<mirror::Class*>(WellKnownClasses::dalvik_system_PathClassLoader)); 5662 Handle<mirror::Object> h_path_class_loader = hs.NewHandle( 5663 h_path_class_class->AllocObject(self)); 5664 DCHECK(h_path_class_loader.Get() != nullptr); 5665 // Set DexPathList. 5666 ArtField* path_list_field = 5667 soa.DecodeField(WellKnownClasses::dalvik_system_PathClassLoader_pathList); 5668 DCHECK(path_list_field != nullptr); 5669 path_list_field->SetObject<false>(h_path_class_loader.Get(), h_dex_path_list.Get()); 5670 5671 // Make a pretend boot-classpath. 5672 // TODO: Should we scan the image? 5673 ArtField* const parent_field = 5674 mirror::Class::FindField(self, hs.NewHandle(h_path_class_loader->GetClass()), "parent", 5675 "Ljava/lang/ClassLoader;"); 5676 DCHECK(parent_field!= nullptr); 5677 mirror::Object* boot_cl = 5678 soa.Decode<mirror::Class*>(WellKnownClasses::java_lang_BootClassLoader)->AllocObject(self); 5679 parent_field->SetObject<false>(h_path_class_loader.Get(), boot_cl); 5680 5681 // Make it a global ref and return. 5682 ScopedLocalRef<jobject> local_ref( 5683 soa.Env(), soa.Env()->AddLocalReference<jobject>(h_path_class_loader.Get())); 5684 return soa.Env()->NewGlobalRef(local_ref.get()); 5685} 5686 5687} // namespace art 5688