class_linker.cc revision 41b175aba41c9365a1c53b8a1afbd17129c87c14
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/time_utils.h" 34#include "base/unix_file/fd_file.h" 35#include "base/value_object.h" 36#include "class_linker-inl.h" 37#include "compiler_callbacks.h" 38#include "debugger.h" 39#include "dex_file-inl.h" 40#include "entrypoints/runtime_asm_entrypoints.h" 41#include "gc_root-inl.h" 42#include "gc/accounting/card_table-inl.h" 43#include "gc/accounting/heap_bitmap.h" 44#include "gc/heap.h" 45#include "gc/space/image_space.h" 46#include "handle_scope.h" 47#include "intern_table.h" 48#include "interpreter/interpreter.h" 49#include "jit/jit.h" 50#include "jit/jit_code_cache.h" 51#include "leb128.h" 52#include "linear_alloc.h" 53#include "oat.h" 54#include "oat_file.h" 55#include "oat_file_assistant.h" 56#include "object_lock.h" 57#include "mirror/art_method-inl.h" 58#include "mirror/class.h" 59#include "mirror/class-inl.h" 60#include "mirror/class_loader.h" 61#include "mirror/dex_cache-inl.h" 62#include "mirror/field.h" 63#include "mirror/iftable-inl.h" 64#include "mirror/method.h" 65#include "mirror/object-inl.h" 66#include "mirror/object_array-inl.h" 67#include "mirror/proxy.h" 68#include "mirror/reference-inl.h" 69#include "mirror/stack_trace_element.h" 70#include "mirror/string-inl.h" 71#include "os.h" 72#include "runtime.h" 73#include "entrypoints/entrypoint_utils.h" 74#include "ScopedLocalRef.h" 75#include "scoped_thread_state_change.h" 76#include "handle_scope-inl.h" 77#include "thread-inl.h" 78#include "utils.h" 79#include "verifier/method_verifier.h" 80#include "well_known_classes.h" 81 82namespace art { 83 84static constexpr bool kSanityCheckObjects = kIsDebugBuild; 85 86static void ThrowNoClassDefFoundError(const char* fmt, ...) 87 __attribute__((__format__(__printf__, 1, 2))) 88 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 89static void ThrowNoClassDefFoundError(const char* fmt, ...) { 90 va_list args; 91 va_start(args, fmt); 92 Thread* self = Thread::Current(); 93 self->ThrowNewExceptionV("Ljava/lang/NoClassDefFoundError;", fmt, args); 94 va_end(args); 95} 96 97static bool HasInitWithString(Thread* self, ClassLinker* class_linker, const char* descriptor) 98 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 99 mirror::ArtMethod* method = self->GetCurrentMethod(nullptr); 100 StackHandleScope<1> hs(self); 101 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(method != nullptr ? 102 method->GetDeclaringClass()->GetClassLoader() 103 : nullptr)); 104 mirror::Class* exception_class = class_linker->FindClass(self, descriptor, class_loader); 105 106 if (exception_class == nullptr) { 107 // No exc class ~ no <init>-with-string. 108 CHECK(self->IsExceptionPending()); 109 self->ClearException(); 110 return false; 111 } 112 113 mirror::ArtMethod* exception_init_method = 114 exception_class->FindDeclaredDirectMethod("<init>", "(Ljava/lang/String;)V"); 115 return exception_init_method != nullptr; 116} 117 118void ClassLinker::ThrowEarlierClassFailure(mirror::Class* c) { 119 // The class failed to initialize on a previous attempt, so we want to throw 120 // a NoClassDefFoundError (v2 2.17.5). The exception to this rule is if we 121 // failed in verification, in which case v2 5.4.1 says we need to re-throw 122 // the previous error. 123 Runtime* const runtime = Runtime::Current(); 124 if (!runtime->IsAotCompiler()) { // Give info if this occurs at runtime. 125 LOG(INFO) << "Rejecting re-init on previously-failed class " << PrettyClass(c); 126 } 127 128 CHECK(c->IsErroneous()) << PrettyClass(c) << " " << c->GetStatus(); 129 Thread* self = Thread::Current(); 130 if (runtime->IsAotCompiler()) { 131 // At compile time, accurate errors and NCDFE are disabled to speed compilation. 132 mirror::Throwable* pre_allocated = runtime->GetPreAllocatedNoClassDefFoundError(); 133 self->SetException(pre_allocated); 134 } else { 135 if (c->GetVerifyErrorClass() != nullptr) { 136 // TODO: change the verifier to store an _instance_, with a useful detail message? 137 // It's possible the exception doesn't have a <init>(String). 138 std::string temp; 139 const char* descriptor = c->GetVerifyErrorClass()->GetDescriptor(&temp); 140 141 if (HasInitWithString(self, this, descriptor)) { 142 self->ThrowNewException(descriptor, PrettyDescriptor(c).c_str()); 143 } else { 144 self->ThrowNewException(descriptor, nullptr); 145 } 146 } else { 147 self->ThrowNewException("Ljava/lang/NoClassDefFoundError;", 148 PrettyDescriptor(c).c_str()); 149 } 150 } 151} 152 153static void VlogClassInitializationFailure(Handle<mirror::Class> klass) 154 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 155 if (VLOG_IS_ON(class_linker)) { 156 std::string temp; 157 LOG(INFO) << "Failed to initialize class " << klass->GetDescriptor(&temp) << " from " 158 << klass->GetLocation() << "\n" << Thread::Current()->GetException()->Dump(); 159 } 160} 161 162static void WrapExceptionInInitializer(Handle<mirror::Class> klass) 163 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 164 Thread* self = Thread::Current(); 165 JNIEnv* env = self->GetJniEnv(); 166 167 ScopedLocalRef<jthrowable> cause(env, env->ExceptionOccurred()); 168 CHECK(cause.get() != nullptr); 169 170 env->ExceptionClear(); 171 bool is_error = env->IsInstanceOf(cause.get(), WellKnownClasses::java_lang_Error); 172 env->Throw(cause.get()); 173 174 // We only wrap non-Error exceptions; an Error can just be used as-is. 175 if (!is_error) { 176 self->ThrowNewWrappedException("Ljava/lang/ExceptionInInitializerError;", nullptr); 177 } 178 VlogClassInitializationFailure(klass); 179} 180 181// Gap between two fields in object layout. 182struct FieldGap { 183 uint32_t start_offset; // The offset from the start of the object. 184 uint32_t size; // The gap size of 1, 2, or 4 bytes. 185}; 186struct FieldGapsComparator { 187 explicit FieldGapsComparator() { 188 } 189 bool operator() (const FieldGap& lhs, const FieldGap& rhs) 190 NO_THREAD_SAFETY_ANALYSIS { 191 // Sort by gap size, largest first. Secondary sort by starting offset. 192 return lhs.size > rhs.size || (lhs.size == rhs.size && lhs.start_offset < rhs.start_offset); 193 } 194}; 195typedef std::priority_queue<FieldGap, std::vector<FieldGap>, FieldGapsComparator> FieldGaps; 196 197// Adds largest aligned gaps to queue of gaps. 198static void AddFieldGap(uint32_t gap_start, uint32_t gap_end, FieldGaps* gaps) { 199 DCHECK(gaps != nullptr); 200 201 uint32_t current_offset = gap_start; 202 while (current_offset != gap_end) { 203 size_t remaining = gap_end - current_offset; 204 if (remaining >= sizeof(uint32_t) && IsAligned<4>(current_offset)) { 205 gaps->push(FieldGap {current_offset, sizeof(uint32_t)}); 206 current_offset += sizeof(uint32_t); 207 } else if (remaining >= sizeof(uint16_t) && IsAligned<2>(current_offset)) { 208 gaps->push(FieldGap {current_offset, sizeof(uint16_t)}); 209 current_offset += sizeof(uint16_t); 210 } else { 211 gaps->push(FieldGap {current_offset, sizeof(uint8_t)}); 212 current_offset += sizeof(uint8_t); 213 } 214 DCHECK_LE(current_offset, gap_end) << "Overran gap"; 215 } 216} 217// Shuffle fields forward, making use of gaps whenever possible. 218template<int n> 219static void ShuffleForward(size_t* current_field_idx, 220 MemberOffset* field_offset, 221 std::deque<ArtField*>* grouped_and_sorted_fields, 222 FieldGaps* gaps) 223 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 224 DCHECK(current_field_idx != nullptr); 225 DCHECK(grouped_and_sorted_fields != nullptr); 226 DCHECK(gaps != nullptr); 227 DCHECK(field_offset != nullptr); 228 229 DCHECK(IsPowerOfTwo(n)); 230 while (!grouped_and_sorted_fields->empty()) { 231 ArtField* field = grouped_and_sorted_fields->front(); 232 Primitive::Type type = field->GetTypeAsPrimitiveType(); 233 if (Primitive::ComponentSize(type) < n) { 234 break; 235 } 236 if (!IsAligned<n>(field_offset->Uint32Value())) { 237 MemberOffset old_offset = *field_offset; 238 *field_offset = MemberOffset(RoundUp(field_offset->Uint32Value(), n)); 239 AddFieldGap(old_offset.Uint32Value(), field_offset->Uint32Value(), gaps); 240 } 241 CHECK(type != Primitive::kPrimNot) << PrettyField(field); // should be primitive types 242 grouped_and_sorted_fields->pop_front(); 243 if (!gaps->empty() && gaps->top().size >= n) { 244 FieldGap gap = gaps->top(); 245 gaps->pop(); 246 DCHECK(IsAligned<n>(gap.start_offset)); 247 field->SetOffset(MemberOffset(gap.start_offset)); 248 if (gap.size > n) { 249 AddFieldGap(gap.start_offset + n, gap.start_offset + gap.size, gaps); 250 } 251 } else { 252 DCHECK(IsAligned<n>(field_offset->Uint32Value())); 253 field->SetOffset(*field_offset); 254 *field_offset = MemberOffset(field_offset->Uint32Value() + n); 255 } 256 ++(*current_field_idx); 257 } 258} 259 260ClassLinker::ClassLinker(InternTable* intern_table) 261 // dex_lock_ is recursive as it may be used in stack dumping. 262 : dex_lock_("ClassLinker dex lock", kDefaultMutexLevel), 263 dex_cache_image_class_lookup_required_(false), 264 failed_dex_cache_class_lookups_(0), 265 class_roots_(nullptr), 266 array_iftable_(nullptr), 267 find_array_class_cache_next_victim_(0), 268 init_done_(false), 269 log_new_dex_caches_roots_(false), 270 log_new_class_table_roots_(false), 271 intern_table_(intern_table), 272 quick_resolution_trampoline_(nullptr), 273 quick_imt_conflict_trampoline_(nullptr), 274 quick_generic_jni_trampoline_(nullptr), 275 quick_to_interpreter_bridge_trampoline_(nullptr), 276 image_pointer_size_(sizeof(void*)) { 277 CHECK(intern_table_ != nullptr); 278 for (size_t i = 0; i < kFindArrayCacheSize; ++i) { 279 find_array_class_cache_[i] = GcRoot<mirror::Class>(nullptr); 280 } 281} 282 283void ClassLinker::InitWithoutImage(std::vector<std::unique_ptr<const DexFile>> boot_class_path) { 284 VLOG(startup) << "ClassLinker::Init"; 285 CHECK(!Runtime::Current()->GetHeap()->HasImageSpace()) << "Runtime has image. We should use it."; 286 287 CHECK(!init_done_); 288 289 // java_lang_Class comes first, it's needed for AllocClass 290 Thread* const self = Thread::Current(); 291 gc::Heap* const heap = Runtime::Current()->GetHeap(); 292 // The GC can't handle an object with a null class since we can't get the size of this object. 293 heap->IncrementDisableMovingGC(self); 294 StackHandleScope<64> hs(self); // 64 is picked arbitrarily. 295 Handle<mirror::Class> java_lang_Class(hs.NewHandle(down_cast<mirror::Class*>( 296 heap->AllocNonMovableObject<true>(self, nullptr, 297 mirror::Class::ClassClassSize(), 298 VoidFunctor())))); 299 CHECK(java_lang_Class.Get() != nullptr); 300 mirror::Class::SetClassClass(java_lang_Class.Get()); 301 java_lang_Class->SetClass(java_lang_Class.Get()); 302 if (kUseBakerOrBrooksReadBarrier) { 303 java_lang_Class->AssertReadBarrierPointer(); 304 } 305 java_lang_Class->SetClassSize(mirror::Class::ClassClassSize()); 306 java_lang_Class->SetPrimitiveType(Primitive::kPrimNot); 307 heap->DecrementDisableMovingGC(self); 308 // AllocClass(mirror::Class*) can now be used 309 310 // Class[] is used for reflection support. 311 Handle<mirror::Class> class_array_class(hs.NewHandle( 312 AllocClass(self, java_lang_Class.Get(), mirror::ObjectArray<mirror::Class>::ClassSize()))); 313 class_array_class->SetComponentType(java_lang_Class.Get()); 314 315 // java_lang_Object comes next so that object_array_class can be created. 316 Handle<mirror::Class> java_lang_Object(hs.NewHandle( 317 AllocClass(self, java_lang_Class.Get(), mirror::Object::ClassSize()))); 318 CHECK(java_lang_Object.Get() != nullptr); 319 // backfill Object as the super class of Class. 320 java_lang_Class->SetSuperClass(java_lang_Object.Get()); 321 mirror::Class::SetStatus(java_lang_Object, mirror::Class::kStatusLoaded, self); 322 323 // Object[] next to hold class roots. 324 Handle<mirror::Class> object_array_class(hs.NewHandle( 325 AllocClass(self, java_lang_Class.Get(), mirror::ObjectArray<mirror::Object>::ClassSize()))); 326 object_array_class->SetComponentType(java_lang_Object.Get()); 327 328 // Setup the char (primitive) class to be used for char[]. 329 Handle<mirror::Class> char_class(hs.NewHandle( 330 AllocClass(self, java_lang_Class.Get(), mirror::Class::PrimitiveClassSize()))); 331 // The primitive char class won't be initialized by 332 // InitializePrimitiveClass until line 459, but strings (and 333 // internal char arrays) will be allocated before that and the 334 // component size, which is computed from the primitive type, needs 335 // to be set here. 336 char_class->SetPrimitiveType(Primitive::kPrimChar); 337 338 // Setup the char[] class to be used for String. 339 Handle<mirror::Class> char_array_class(hs.NewHandle( 340 AllocClass(self, java_lang_Class.Get(), 341 mirror::Array::ClassSize()))); 342 char_array_class->SetComponentType(char_class.Get()); 343 mirror::CharArray::SetArrayClass(char_array_class.Get()); 344 345 // Setup String. 346 Handle<mirror::Class> java_lang_String(hs.NewHandle( 347 AllocClass(self, java_lang_Class.Get(), mirror::String::ClassSize()))); 348 mirror::String::SetClass(java_lang_String.Get()); 349 mirror::Class::SetStatus(java_lang_String, mirror::Class::kStatusResolved, self); 350 java_lang_String->SetStringClass(); 351 352 // Setup java.lang.ref.Reference. 353 Handle<mirror::Class> java_lang_ref_Reference(hs.NewHandle( 354 AllocClass(self, java_lang_Class.Get(), mirror::Reference::ClassSize()))); 355 mirror::Reference::SetClass(java_lang_ref_Reference.Get()); 356 java_lang_ref_Reference->SetObjectSize(mirror::Reference::InstanceSize()); 357 mirror::Class::SetStatus(java_lang_ref_Reference, mirror::Class::kStatusResolved, self); 358 359 // Create storage for root classes, save away our work so far (requires descriptors). 360 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class>>( 361 mirror::ObjectArray<mirror::Class>::Alloc(self, object_array_class.Get(), 362 kClassRootsMax)); 363 CHECK(!class_roots_.IsNull()); 364 SetClassRoot(kJavaLangClass, java_lang_Class.Get()); 365 SetClassRoot(kJavaLangObject, java_lang_Object.Get()); 366 SetClassRoot(kClassArrayClass, class_array_class.Get()); 367 SetClassRoot(kObjectArrayClass, object_array_class.Get()); 368 SetClassRoot(kCharArrayClass, char_array_class.Get()); 369 SetClassRoot(kJavaLangString, java_lang_String.Get()); 370 SetClassRoot(kJavaLangRefReference, java_lang_ref_Reference.Get()); 371 372 // Setup the primitive type classes. 373 SetClassRoot(kPrimitiveBoolean, CreatePrimitiveClass(self, Primitive::kPrimBoolean)); 374 SetClassRoot(kPrimitiveByte, CreatePrimitiveClass(self, Primitive::kPrimByte)); 375 SetClassRoot(kPrimitiveShort, CreatePrimitiveClass(self, Primitive::kPrimShort)); 376 SetClassRoot(kPrimitiveInt, CreatePrimitiveClass(self, Primitive::kPrimInt)); 377 SetClassRoot(kPrimitiveLong, CreatePrimitiveClass(self, Primitive::kPrimLong)); 378 SetClassRoot(kPrimitiveFloat, CreatePrimitiveClass(self, Primitive::kPrimFloat)); 379 SetClassRoot(kPrimitiveDouble, CreatePrimitiveClass(self, Primitive::kPrimDouble)); 380 SetClassRoot(kPrimitiveVoid, CreatePrimitiveClass(self, Primitive::kPrimVoid)); 381 382 // Create array interface entries to populate once we can load system classes. 383 array_iftable_ = GcRoot<mirror::IfTable>(AllocIfTable(self, 2)); 384 385 // Create int array type for AllocDexCache (done in AppendToBootClassPath). 386 Handle<mirror::Class> int_array_class(hs.NewHandle( 387 AllocClass(self, java_lang_Class.Get(), mirror::Array::ClassSize()))); 388 int_array_class->SetComponentType(GetClassRoot(kPrimitiveInt)); 389 mirror::IntArray::SetArrayClass(int_array_class.Get()); 390 SetClassRoot(kIntArrayClass, int_array_class.Get()); 391 392 // Create long array type for AllocDexCache (done in AppendToBootClassPath). 393 Handle<mirror::Class> long_array_class(hs.NewHandle( 394 AllocClass(self, java_lang_Class.Get(), mirror::Array::ClassSize()))); 395 long_array_class->SetComponentType(GetClassRoot(kPrimitiveLong)); 396 mirror::LongArray::SetArrayClass(long_array_class.Get()); 397 SetClassRoot(kLongArrayClass, long_array_class.Get()); 398 399 // now that these are registered, we can use AllocClass() and AllocObjectArray 400 401 // Set up DexCache. This cannot be done later since AppendToBootClassPath calls AllocDexCache. 402 Handle<mirror::Class> java_lang_DexCache(hs.NewHandle( 403 AllocClass(self, java_lang_Class.Get(), mirror::DexCache::ClassSize()))); 404 SetClassRoot(kJavaLangDexCache, java_lang_DexCache.Get()); 405 java_lang_DexCache->SetObjectSize(mirror::DexCache::InstanceSize()); 406 mirror::Class::SetStatus(java_lang_DexCache, mirror::Class::kStatusResolved, self); 407 408 // Constructor, Method, and AbstractMethod are necessary so 409 // that FindClass can link members. 410 411 Handle<mirror::Class> java_lang_reflect_ArtMethod(hs.NewHandle( 412 AllocClass(self, java_lang_Class.Get(), mirror::ArtMethod::ClassSize()))); 413 CHECK(java_lang_reflect_ArtMethod.Get() != nullptr); 414 size_t pointer_size = GetInstructionSetPointerSize(Runtime::Current()->GetInstructionSet()); 415 java_lang_reflect_ArtMethod->SetObjectSize(mirror::ArtMethod::InstanceSize(pointer_size)); 416 SetClassRoot(kJavaLangReflectArtMethod, java_lang_reflect_ArtMethod.Get()); 417 mirror::Class::SetStatus(java_lang_reflect_ArtMethod, mirror::Class::kStatusResolved, self); 418 mirror::ArtMethod::SetClass(java_lang_reflect_ArtMethod.Get()); 419 420 // Set up array classes for string, field, method 421 Handle<mirror::Class> object_array_string(hs.NewHandle( 422 AllocClass(self, java_lang_Class.Get(), 423 mirror::ObjectArray<mirror::String>::ClassSize()))); 424 object_array_string->SetComponentType(java_lang_String.Get()); 425 SetClassRoot(kJavaLangStringArrayClass, object_array_string.Get()); 426 427 Handle<mirror::Class> object_array_art_method(hs.NewHandle( 428 AllocClass(self, java_lang_Class.Get(), 429 mirror::ObjectArray<mirror::ArtMethod>::ClassSize()))); 430 object_array_art_method->SetComponentType(java_lang_reflect_ArtMethod.Get()); 431 SetClassRoot(kJavaLangReflectArtMethodArrayClass, object_array_art_method.Get()); 432 433 // Setup boot_class_path_ and register class_path now that we can use AllocObjectArray to create 434 // DexCache instances. Needs to be after String, Field, Method arrays since AllocDexCache uses 435 // these roots. 436 CHECK_NE(0U, boot_class_path.size()); 437 for (auto& dex_file : boot_class_path) { 438 CHECK(dex_file.get() != nullptr); 439 AppendToBootClassPath(self, *dex_file); 440 opened_dex_files_.push_back(std::move(dex_file)); 441 } 442 443 // now we can use FindSystemClass 444 445 // run char class through InitializePrimitiveClass to finish init 446 InitializePrimitiveClass(char_class.Get(), Primitive::kPrimChar); 447 SetClassRoot(kPrimitiveChar, char_class.Get()); // needs descriptor 448 449 // Create runtime resolution and imt conflict methods. Also setup the default imt. 450 Runtime* runtime = Runtime::Current(); 451 runtime->SetResolutionMethod(runtime->CreateResolutionMethod()); 452 runtime->SetImtConflictMethod(runtime->CreateImtConflictMethod()); 453 runtime->SetImtUnimplementedMethod(runtime->CreateImtConflictMethod()); 454 runtime->SetDefaultImt(runtime->CreateDefaultImt(this)); 455 456 // Set up GenericJNI entrypoint. That is mainly a hack for common_compiler_test.h so that 457 // we do not need friend classes or a publicly exposed setter. 458 quick_generic_jni_trampoline_ = GetQuickGenericJniStub(); 459 if (!runtime->IsAotCompiler()) { 460 // We need to set up the generic trampolines since we don't have an image. 461 quick_resolution_trampoline_ = GetQuickResolutionStub(); 462 quick_imt_conflict_trampoline_ = GetQuickImtConflictStub(); 463 quick_to_interpreter_bridge_trampoline_ = GetQuickToInterpreterBridge(); 464 } 465 466 // Object, String and DexCache need to be rerun through FindSystemClass to finish init 467 mirror::Class::SetStatus(java_lang_Object, mirror::Class::kStatusNotReady, self); 468 CHECK_EQ(java_lang_Object.Get(), FindSystemClass(self, "Ljava/lang/Object;")); 469 CHECK_EQ(java_lang_Object->GetObjectSize(), mirror::Object::InstanceSize()); 470 mirror::Class::SetStatus(java_lang_String, mirror::Class::kStatusNotReady, self); 471 mirror::Class* String_class = FindSystemClass(self, "Ljava/lang/String;"); 472 if (java_lang_String.Get() != String_class) { 473 std::ostringstream os1, os2; 474 java_lang_String->DumpClass(os1, mirror::Class::kDumpClassFullDetail); 475 String_class->DumpClass(os2, mirror::Class::kDumpClassFullDetail); 476 LOG(FATAL) << os1.str() << "\n\n" << os2.str(); 477 } 478 mirror::Class::SetStatus(java_lang_DexCache, mirror::Class::kStatusNotReady, self); 479 CHECK_EQ(java_lang_DexCache.Get(), FindSystemClass(self, "Ljava/lang/DexCache;")); 480 CHECK_EQ(java_lang_DexCache->GetObjectSize(), mirror::DexCache::InstanceSize()); 481 482 // Setup the primitive array type classes - can't be done until Object has a vtable. 483 SetClassRoot(kBooleanArrayClass, FindSystemClass(self, "[Z")); 484 mirror::BooleanArray::SetArrayClass(GetClassRoot(kBooleanArrayClass)); 485 486 SetClassRoot(kByteArrayClass, FindSystemClass(self, "[B")); 487 mirror::ByteArray::SetArrayClass(GetClassRoot(kByteArrayClass)); 488 489 CHECK_EQ(char_array_class.Get(), FindSystemClass(self, "[C")); 490 491 SetClassRoot(kShortArrayClass, FindSystemClass(self, "[S")); 492 mirror::ShortArray::SetArrayClass(GetClassRoot(kShortArrayClass)); 493 494 CHECK_EQ(int_array_class.Get(), FindSystemClass(self, "[I")); 495 496 CHECK_EQ(long_array_class.Get(), FindSystemClass(self, "[J")); 497 498 SetClassRoot(kFloatArrayClass, FindSystemClass(self, "[F")); 499 mirror::FloatArray::SetArrayClass(GetClassRoot(kFloatArrayClass)); 500 501 SetClassRoot(kDoubleArrayClass, FindSystemClass(self, "[D")); 502 mirror::DoubleArray::SetArrayClass(GetClassRoot(kDoubleArrayClass)); 503 504 CHECK_EQ(class_array_class.Get(), FindSystemClass(self, "[Ljava/lang/Class;")); 505 506 CHECK_EQ(object_array_class.Get(), FindSystemClass(self, "[Ljava/lang/Object;")); 507 508 // Setup the single, global copy of "iftable". 509 auto java_lang_Cloneable = hs.NewHandle(FindSystemClass(self, "Ljava/lang/Cloneable;")); 510 CHECK(java_lang_Cloneable.Get() != nullptr); 511 auto java_io_Serializable = hs.NewHandle(FindSystemClass(self, "Ljava/io/Serializable;")); 512 CHECK(java_io_Serializable.Get() != nullptr); 513 // We assume that Cloneable/Serializable don't have superinterfaces -- normally we'd have to 514 // crawl up and explicitly list all of the supers as well. 515 array_iftable_.Read()->SetInterface(0, java_lang_Cloneable.Get()); 516 array_iftable_.Read()->SetInterface(1, java_io_Serializable.Get()); 517 518 // Sanity check Class[] and Object[]'s interfaces. GetDirectInterface may cause thread 519 // suspension. 520 CHECK_EQ(java_lang_Cloneable.Get(), 521 mirror::Class::GetDirectInterface(self, class_array_class, 0)); 522 CHECK_EQ(java_io_Serializable.Get(), 523 mirror::Class::GetDirectInterface(self, class_array_class, 1)); 524 CHECK_EQ(java_lang_Cloneable.Get(), 525 mirror::Class::GetDirectInterface(self, object_array_class, 0)); 526 CHECK_EQ(java_io_Serializable.Get(), 527 mirror::Class::GetDirectInterface(self, object_array_class, 1)); 528 // Run Class, ArtField, and ArtMethod through FindSystemClass. This initializes their 529 // dex_cache_ fields and register them in class_table_. 530 CHECK_EQ(java_lang_Class.Get(), FindSystemClass(self, "Ljava/lang/Class;")); 531 532 mirror::Class::SetStatus(java_lang_reflect_ArtMethod, mirror::Class::kStatusNotReady, self); 533 CHECK_EQ(java_lang_reflect_ArtMethod.Get(), 534 FindSystemClass(self, "Ljava/lang/reflect/ArtMethod;")); 535 CHECK_EQ(object_array_string.Get(), 536 FindSystemClass(self, GetClassRootDescriptor(kJavaLangStringArrayClass))); 537 CHECK_EQ(object_array_art_method.Get(), 538 FindSystemClass(self, GetClassRootDescriptor(kJavaLangReflectArtMethodArrayClass))); 539 540 // End of special init trickery, subsequent classes may be loaded via FindSystemClass. 541 542 // Create java.lang.reflect.Proxy root. 543 SetClassRoot(kJavaLangReflectProxy, FindSystemClass(self, "Ljava/lang/reflect/Proxy;")); 544 545 // Create java.lang.reflect.Field.class root. 546 auto* class_root = FindSystemClass(self, "Ljava/lang/reflect/Field;"); 547 CHECK(class_root != nullptr); 548 SetClassRoot(kJavaLangReflectField, class_root); 549 mirror::Field::SetClass(class_root); 550 551 // Create java.lang.reflect.Field array root. 552 class_root = FindSystemClass(self, "[Ljava/lang/reflect/Field;"); 553 CHECK(class_root != nullptr); 554 SetClassRoot(kJavaLangReflectFieldArrayClass, class_root); 555 mirror::Field::SetArrayClass(class_root); 556 557 // Create java.lang.reflect.Constructor.class root and array root. 558 class_root = FindSystemClass(self, "Ljava/lang/reflect/Constructor;"); 559 CHECK(class_root != nullptr); 560 SetClassRoot(kJavaLangReflectConstructor, class_root); 561 mirror::Constructor::SetClass(class_root); 562 class_root = FindSystemClass(self, "[Ljava/lang/reflect/Constructor;"); 563 CHECK(class_root != nullptr); 564 SetClassRoot(kJavaLangReflectConstructorArrayClass, class_root); 565 mirror::Constructor::SetArrayClass(class_root); 566 567 // Create java.lang.reflect.Method.class root and array root. 568 class_root = FindSystemClass(self, "Ljava/lang/reflect/Method;"); 569 CHECK(class_root != nullptr); 570 SetClassRoot(kJavaLangReflectMethod, class_root); 571 mirror::Method::SetClass(class_root); 572 class_root = FindSystemClass(self, "[Ljava/lang/reflect/Method;"); 573 CHECK(class_root != nullptr); 574 SetClassRoot(kJavaLangReflectMethodArrayClass, class_root); 575 mirror::Method::SetArrayClass(class_root); 576 577 // java.lang.ref classes need to be specially flagged, but otherwise are normal classes 578 // finish initializing Reference class 579 mirror::Class::SetStatus(java_lang_ref_Reference, mirror::Class::kStatusNotReady, self); 580 CHECK_EQ(java_lang_ref_Reference.Get(), FindSystemClass(self, "Ljava/lang/ref/Reference;")); 581 CHECK_EQ(java_lang_ref_Reference->GetObjectSize(), mirror::Reference::InstanceSize()); 582 CHECK_EQ(java_lang_ref_Reference->GetClassSize(), mirror::Reference::ClassSize()); 583 class_root = FindSystemClass(self, "Ljava/lang/ref/FinalizerReference;"); 584 class_root->SetAccessFlags(class_root->GetAccessFlags() | 585 kAccClassIsReference | kAccClassIsFinalizerReference); 586 class_root = FindSystemClass(self, "Ljava/lang/ref/PhantomReference;"); 587 class_root->SetAccessFlags(class_root->GetAccessFlags() | kAccClassIsReference | 588 kAccClassIsPhantomReference); 589 class_root = FindSystemClass(self, "Ljava/lang/ref/SoftReference;"); 590 class_root->SetAccessFlags(class_root->GetAccessFlags() | kAccClassIsReference); 591 class_root = FindSystemClass(self, "Ljava/lang/ref/WeakReference;"); 592 class_root->SetAccessFlags(class_root->GetAccessFlags() | kAccClassIsReference | 593 kAccClassIsWeakReference); 594 595 // Setup the ClassLoader, verifying the object_size_. 596 class_root = FindSystemClass(self, "Ljava/lang/ClassLoader;"); 597 CHECK_EQ(class_root->GetObjectSize(), mirror::ClassLoader::InstanceSize()); 598 SetClassRoot(kJavaLangClassLoader, class_root); 599 600 // Set up java.lang.Throwable, java.lang.ClassNotFoundException, and 601 // java.lang.StackTraceElement as a convenience. 602 SetClassRoot(kJavaLangThrowable, FindSystemClass(self, "Ljava/lang/Throwable;")); 603 mirror::Throwable::SetClass(GetClassRoot(kJavaLangThrowable)); 604 SetClassRoot(kJavaLangClassNotFoundException, 605 FindSystemClass(self, "Ljava/lang/ClassNotFoundException;")); 606 SetClassRoot(kJavaLangStackTraceElement, FindSystemClass(self, "Ljava/lang/StackTraceElement;")); 607 SetClassRoot(kJavaLangStackTraceElementArrayClass, 608 FindSystemClass(self, "[Ljava/lang/StackTraceElement;")); 609 mirror::StackTraceElement::SetClass(GetClassRoot(kJavaLangStackTraceElement)); 610 611 // Ensure void type is resolved in the core's dex cache so java.lang.Void is correctly 612 // initialized. 613 { 614 const DexFile& dex_file = java_lang_Object->GetDexFile(); 615 const DexFile::StringId* void_string_id = dex_file.FindStringId("V"); 616 CHECK(void_string_id != nullptr); 617 uint32_t void_string_index = dex_file.GetIndexForStringId(*void_string_id); 618 const DexFile::TypeId* void_type_id = dex_file.FindTypeId(void_string_index); 619 CHECK(void_type_id != nullptr); 620 uint16_t void_type_idx = dex_file.GetIndexForTypeId(*void_type_id); 621 // Now we resolve void type so the dex cache contains it. We use java.lang.Object class 622 // as referrer so the used dex cache is core's one. 623 mirror::Class* resolved_type = ResolveType(dex_file, void_type_idx, java_lang_Object.Get()); 624 CHECK_EQ(resolved_type, GetClassRoot(kPrimitiveVoid)); 625 self->AssertNoPendingException(); 626 } 627 628 FinishInit(self); 629 630 VLOG(startup) << "ClassLinker::InitFromCompiler exiting"; 631} 632 633void ClassLinker::FinishInit(Thread* self) { 634 VLOG(startup) << "ClassLinker::FinishInit entering"; 635 636 // Let the heap know some key offsets into java.lang.ref instances 637 // Note: we hard code the field indexes here rather than using FindInstanceField 638 // as the types of the field can't be resolved prior to the runtime being 639 // fully initialized 640 mirror::Class* java_lang_ref_Reference = GetClassRoot(kJavaLangRefReference); 641 mirror::Class* java_lang_ref_FinalizerReference = 642 FindSystemClass(self, "Ljava/lang/ref/FinalizerReference;"); 643 644 ArtField* pendingNext = java_lang_ref_Reference->GetInstanceField(0); 645 CHECK_STREQ(pendingNext->GetName(), "pendingNext"); 646 CHECK_STREQ(pendingNext->GetTypeDescriptor(), "Ljava/lang/ref/Reference;"); 647 648 ArtField* queue = java_lang_ref_Reference->GetInstanceField(1); 649 CHECK_STREQ(queue->GetName(), "queue"); 650 CHECK_STREQ(queue->GetTypeDescriptor(), "Ljava/lang/ref/ReferenceQueue;"); 651 652 ArtField* queueNext = java_lang_ref_Reference->GetInstanceField(2); 653 CHECK_STREQ(queueNext->GetName(), "queueNext"); 654 CHECK_STREQ(queueNext->GetTypeDescriptor(), "Ljava/lang/ref/Reference;"); 655 656 ArtField* referent = java_lang_ref_Reference->GetInstanceField(3); 657 CHECK_STREQ(referent->GetName(), "referent"); 658 CHECK_STREQ(referent->GetTypeDescriptor(), "Ljava/lang/Object;"); 659 660 ArtField* zombie = java_lang_ref_FinalizerReference->GetInstanceField(2); 661 CHECK_STREQ(zombie->GetName(), "zombie"); 662 CHECK_STREQ(zombie->GetTypeDescriptor(), "Ljava/lang/Object;"); 663 664 // ensure all class_roots_ are initialized 665 for (size_t i = 0; i < kClassRootsMax; i++) { 666 ClassRoot class_root = static_cast<ClassRoot>(i); 667 mirror::Class* klass = GetClassRoot(class_root); 668 CHECK(klass != nullptr); 669 DCHECK(klass->IsArrayClass() || klass->IsPrimitive() || klass->GetDexCache() != nullptr); 670 // note SetClassRoot does additional validation. 671 // if possible add new checks there to catch errors early 672 } 673 674 CHECK(!array_iftable_.IsNull()); 675 676 // disable the slow paths in FindClass and CreatePrimitiveClass now 677 // that Object, Class, and Object[] are setup 678 init_done_ = true; 679 680 VLOG(startup) << "ClassLinker::FinishInit exiting"; 681} 682 683void ClassLinker::RunRootClinits() { 684 Thread* self = Thread::Current(); 685 for (size_t i = 0; i < ClassLinker::kClassRootsMax; ++i) { 686 mirror::Class* c = GetClassRoot(ClassRoot(i)); 687 if (!c->IsArrayClass() && !c->IsPrimitive()) { 688 StackHandleScope<1> hs(self); 689 Handle<mirror::Class> h_class(hs.NewHandle(GetClassRoot(ClassRoot(i)))); 690 EnsureInitialized(self, h_class, true, true); 691 self->AssertNoPendingException(); 692 } 693 } 694} 695 696const OatFile* ClassLinker::RegisterOatFile(const OatFile* oat_file) { 697 WriterMutexLock mu(Thread::Current(), dex_lock_); 698 if (kIsDebugBuild) { 699 for (size_t i = 0; i < oat_files_.size(); ++i) { 700 CHECK_NE(oat_file, oat_files_[i]) << oat_file->GetLocation(); 701 } 702 } 703 VLOG(class_linker) << "Registering " << oat_file->GetLocation(); 704 oat_files_.push_back(oat_file); 705 return oat_file; 706} 707 708OatFile& ClassLinker::GetImageOatFile(gc::space::ImageSpace* space) { 709 VLOG(startup) << "ClassLinker::GetImageOatFile entering"; 710 OatFile* oat_file = space->ReleaseOatFile(); 711 CHECK_EQ(RegisterOatFile(oat_file), oat_file); 712 VLOG(startup) << "ClassLinker::GetImageOatFile exiting"; 713 return *oat_file; 714} 715 716class DexFileAndClassPair : ValueObject { 717 public: 718 DexFileAndClassPair(const DexFile* dex_file, size_t current_class_index, bool from_loaded_oat) 719 : cached_descriptor_(GetClassDescriptor(dex_file, current_class_index)), 720 dex_file_(dex_file), 721 current_class_index_(current_class_index), 722 from_loaded_oat_(from_loaded_oat) {} 723 724 DexFileAndClassPair(const DexFileAndClassPair&) = default; 725 726 DexFileAndClassPair& operator=(const DexFileAndClassPair& rhs) { 727 cached_descriptor_ = rhs.cached_descriptor_; 728 dex_file_ = rhs.dex_file_; 729 current_class_index_ = rhs.current_class_index_; 730 from_loaded_oat_ = rhs.from_loaded_oat_; 731 return *this; 732 } 733 734 const char* GetCachedDescriptor() const { 735 return cached_descriptor_; 736 } 737 738 bool operator<(const DexFileAndClassPair& rhs) const { 739 const char* lhsDescriptor = cached_descriptor_; 740 const char* rhsDescriptor = rhs.cached_descriptor_; 741 int cmp = strcmp(lhsDescriptor, rhsDescriptor); 742 if (cmp != 0) { 743 // Note that the order must be reversed. We want to iterate over the classes in dex files. 744 // They are sorted lexicographically. Thus, the priority-queue must be a min-queue. 745 return cmp > 0; 746 } 747 return dex_file_ < rhs.dex_file_; 748 } 749 750 bool DexFileHasMoreClasses() const { 751 return current_class_index_ + 1 < dex_file_->NumClassDefs(); 752 } 753 754 DexFileAndClassPair GetNext() const { 755 return DexFileAndClassPair(dex_file_, current_class_index_ + 1, from_loaded_oat_); 756 } 757 758 size_t GetCurrentClassIndex() const { 759 return current_class_index_; 760 } 761 762 bool FromLoadedOat() const { 763 return from_loaded_oat_; 764 } 765 766 const DexFile* GetDexFile() const { 767 return dex_file_; 768 } 769 770 void DeleteDexFile() { 771 delete dex_file_; 772 dex_file_ = nullptr; 773 } 774 775 private: 776 static const char* GetClassDescriptor(const DexFile* dex_file, size_t index) { 777 const DexFile::ClassDef& class_def = dex_file->GetClassDef(static_cast<uint16_t>(index)); 778 return dex_file->StringByTypeIdx(class_def.class_idx_); 779 } 780 781 const char* cached_descriptor_; 782 const DexFile* dex_file_; 783 size_t current_class_index_; 784 bool from_loaded_oat_; // We only need to compare mismatches between what we load now 785 // and what was loaded before. Any old duplicates must have been 786 // OK, and any new "internal" duplicates are as well (they must 787 // be from multidex, which resolves correctly). 788}; 789 790static void AddDexFilesFromOat(const OatFile* oat_file, bool already_loaded, 791 std::priority_queue<DexFileAndClassPair>* heap) { 792 const std::vector<const OatDexFile*>& oat_dex_files = oat_file->GetOatDexFiles(); 793 for (const OatDexFile* oat_dex_file : oat_dex_files) { 794 std::string error; 795 std::unique_ptr<const DexFile> dex_file = oat_dex_file->OpenDexFile(&error); 796 if (dex_file.get() == nullptr) { 797 LOG(WARNING) << "Could not create dex file from oat file: " << error; 798 } else { 799 if (dex_file->NumClassDefs() > 0U) { 800 heap->emplace(dex_file.release(), 0U, already_loaded); 801 } 802 } 803 } 804} 805 806static void AddNext(DexFileAndClassPair* original, 807 std::priority_queue<DexFileAndClassPair>* heap) { 808 if (original->DexFileHasMoreClasses()) { 809 heap->push(original->GetNext()); 810 } else { 811 // Need to delete the dex file. 812 original->DeleteDexFile(); 813 } 814} 815 816static void FreeDexFilesInHeap(std::priority_queue<DexFileAndClassPair>* heap) { 817 while (!heap->empty()) { 818 delete heap->top().GetDexFile(); 819 heap->pop(); 820 } 821} 822 823const OatFile* ClassLinker::GetBootOatFile() { 824 // To grab the boot oat, look at the dex files in the boot classpath. Any of those is fine, as 825 // they were all compiled into the same oat file. So grab the first one, which is guaranteed to 826 // exist if the boot class-path isn't empty. 827 if (boot_class_path_.empty()) { 828 return nullptr; 829 } 830 const DexFile* boot_dex_file = boot_class_path_[0]; 831 // Is it from an oat file? 832 if (boot_dex_file->GetOatDexFile() != nullptr) { 833 return boot_dex_file->GetOatDexFile()->GetOatFile(); 834 } 835 return nullptr; 836} 837 838const OatFile* ClassLinker::GetPrimaryOatFile() { 839 ReaderMutexLock mu(Thread::Current(), dex_lock_); 840 const OatFile* boot_oat_file = GetBootOatFile(); 841 if (boot_oat_file != nullptr) { 842 for (const OatFile* oat_file : oat_files_) { 843 if (oat_file != boot_oat_file) { 844 return oat_file; 845 } 846 } 847 } 848 return nullptr; 849} 850 851// Check for class-def collisions in dex files. 852// 853// This works by maintaining a heap with one class from each dex file, sorted by the class 854// descriptor. Then a dex-file/class pair is continually removed from the heap and compared 855// against the following top element. If the descriptor is the same, it is now checked whether 856// the two elements agree on whether their dex file was from an already-loaded oat-file or the 857// new oat file. Any disagreement indicates a collision. 858bool ClassLinker::HasCollisions(const OatFile* oat_file, std::string* error_msg) { 859 // Dex files are registered late - once a class is actually being loaded. We have to compare 860 // against the open oat files. Take the dex_lock_ that protects oat_files_ accesses. 861 ReaderMutexLock mu(Thread::Current(), dex_lock_); 862 863 std::priority_queue<DexFileAndClassPair> queue; 864 865 // Add dex files from already loaded oat files, but skip boot. 866 { 867 const OatFile* boot_oat = GetBootOatFile(); 868 for (const OatFile* loaded_oat_file : oat_files_) { 869 if (loaded_oat_file == boot_oat) { 870 continue; 871 } 872 AddDexFilesFromOat(loaded_oat_file, true, &queue); 873 } 874 } 875 876 if (queue.empty()) { 877 // No other oat files, return early. 878 return false; 879 } 880 881 // Add dex files from the oat file to check. 882 AddDexFilesFromOat(oat_file, false, &queue); 883 884 // Now drain the queue. 885 while (!queue.empty()) { 886 DexFileAndClassPair compare_pop = queue.top(); 887 queue.pop(); 888 889 // Compare against the following elements. 890 while (!queue.empty()) { 891 DexFileAndClassPair top = queue.top(); 892 893 if (strcmp(compare_pop.GetCachedDescriptor(), top.GetCachedDescriptor()) == 0) { 894 // Same descriptor. Check whether it's crossing old-oat-files to new-oat-files. 895 if (compare_pop.FromLoadedOat() != top.FromLoadedOat()) { 896 *error_msg = 897 StringPrintf("Found duplicated class when checking oat files: '%s' in %s and %s", 898 compare_pop.GetCachedDescriptor(), 899 compare_pop.GetDexFile()->GetLocation().c_str(), 900 top.GetDexFile()->GetLocation().c_str()); 901 FreeDexFilesInHeap(&queue); 902 return true; 903 } 904 // Pop it. 905 queue.pop(); 906 AddNext(&top, &queue); 907 } else { 908 // Something else. Done here. 909 break; 910 } 911 } 912 AddNext(&compare_pop, &queue); 913 } 914 915 return false; 916} 917 918std::vector<std::unique_ptr<const DexFile>> ClassLinker::OpenDexFilesFromOat( 919 const char* dex_location, const char* oat_location, 920 std::vector<std::string>* error_msgs) { 921 CHECK(error_msgs != nullptr); 922 923 // Verify we aren't holding the mutator lock, which could starve GC if we 924 // have to generate or relocate an oat file. 925 Locks::mutator_lock_->AssertNotHeld(Thread::Current()); 926 927 OatFileAssistant oat_file_assistant(dex_location, oat_location, kRuntimeISA, 928 !Runtime::Current()->IsAotCompiler()); 929 930 // Lock the target oat location to avoid races generating and loading the 931 // oat file. 932 std::string error_msg; 933 if (!oat_file_assistant.Lock(&error_msg)) { 934 // Don't worry too much if this fails. If it does fail, it's unlikely we 935 // can generate an oat file anyway. 936 VLOG(class_linker) << "OatFileAssistant::Lock: " << error_msg; 937 } 938 939 // Check if we already have an up-to-date oat file open. 940 const OatFile* source_oat_file = nullptr; 941 { 942 ReaderMutexLock mu(Thread::Current(), dex_lock_); 943 for (const OatFile* oat_file : oat_files_) { 944 CHECK(oat_file != nullptr); 945 if (oat_file_assistant.GivenOatFileIsUpToDate(*oat_file)) { 946 source_oat_file = oat_file; 947 break; 948 } 949 } 950 } 951 952 // If we didn't have an up-to-date oat file open, try to load one from disk. 953 if (source_oat_file == nullptr) { 954 // Update the oat file on disk if we can. This may fail, but that's okay. 955 // Best effort is all that matters here. 956 if (!oat_file_assistant.MakeUpToDate(&error_msg)) { 957 LOG(WARNING) << error_msg; 958 } 959 960 // Get the oat file on disk. 961 std::unique_ptr<OatFile> oat_file = oat_file_assistant.GetBestOatFile(); 962 if (oat_file.get() != nullptr) { 963 // Take the file only if it has no collisions, or we must take it because of preopting. 964 bool accept_oat_file = !HasCollisions(oat_file.get(), &error_msg); 965 if (!accept_oat_file) { 966 // Failed the collision check. Print warning. 967 if (Runtime::Current()->IsDexFileFallbackEnabled()) { 968 LOG(WARNING) << "Found duplicate classes, falling back to interpreter mode for " 969 << dex_location; 970 } else { 971 LOG(WARNING) << "Found duplicate classes, dex-file-fallback disabled, will be failing to " 972 " load classes for " << dex_location; 973 } 974 LOG(WARNING) << error_msg; 975 976 // However, if the app was part of /system and preopted, there is no original dex file 977 // available. In that case grudgingly accept the oat file. 978 if (!DexFile::MaybeDex(dex_location)) { 979 accept_oat_file = true; 980 LOG(WARNING) << "Dex location " << dex_location << " does not seem to include dex file. " 981 << "Allow oat file use. This is potentially dangerous."; 982 } 983 } 984 985 if (accept_oat_file) { 986 source_oat_file = oat_file.release(); 987 RegisterOatFile(source_oat_file); 988 } 989 } 990 } 991 992 std::vector<std::unique_ptr<const DexFile>> dex_files; 993 994 // Load the dex files from the oat file. 995 if (source_oat_file != nullptr) { 996 dex_files = oat_file_assistant.LoadDexFiles(*source_oat_file, dex_location); 997 if (dex_files.empty()) { 998 error_msgs->push_back("Failed to open dex files from " 999 + source_oat_file->GetLocation()); 1000 } 1001 } 1002 1003 // Fall back to running out of the original dex file if we couldn't load any 1004 // dex_files from the oat file. 1005 if (dex_files.empty()) { 1006 if (Runtime::Current()->IsDexFileFallbackEnabled()) { 1007 if (!DexFile::Open(dex_location, dex_location, &error_msg, &dex_files)) { 1008 LOG(WARNING) << error_msg; 1009 error_msgs->push_back("Failed to open dex files from " + std::string(dex_location)); 1010 } 1011 } else { 1012 error_msgs->push_back("Fallback mode disabled, skipping dex files."); 1013 } 1014 } 1015 return dex_files; 1016} 1017 1018const OatFile* ClassLinker::FindOpenedOatFileFromOatLocation(const std::string& oat_location) { 1019 ReaderMutexLock mu(Thread::Current(), dex_lock_); 1020 for (size_t i = 0; i < oat_files_.size(); i++) { 1021 const OatFile* oat_file = oat_files_[i]; 1022 DCHECK(oat_file != nullptr); 1023 if (oat_file->GetLocation() == oat_location) { 1024 return oat_file; 1025 } 1026 } 1027 return nullptr; 1028} 1029 1030void ClassLinker::InitFromImageInterpretOnlyCallback(mirror::Object* obj, void* arg) { 1031 ClassLinker* class_linker = reinterpret_cast<ClassLinker*>(arg); 1032 DCHECK(obj != nullptr); 1033 DCHECK(class_linker != nullptr); 1034 if (obj->IsArtMethod()) { 1035 mirror::ArtMethod* method = obj->AsArtMethod(); 1036 if (!method->IsNative()) { 1037 const size_t pointer_size = class_linker->image_pointer_size_; 1038 method->SetEntryPointFromInterpreterPtrSize(artInterpreterToInterpreterBridge, pointer_size); 1039 if (!method->IsRuntimeMethod() && method != Runtime::Current()->GetResolutionMethod()) { 1040 method->SetEntryPointFromQuickCompiledCodePtrSize(GetQuickToInterpreterBridge(), 1041 pointer_size); 1042 } 1043 } 1044 } 1045} 1046 1047void SanityCheckObjectsCallback(mirror::Object* obj, void* arg ATTRIBUTE_UNUSED) 1048 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1049 DCHECK(obj != nullptr); 1050 CHECK(obj->GetClass() != nullptr) << "Null class " << obj; 1051 CHECK(obj->GetClass()->GetClass() != nullptr) << "Null class class " << obj; 1052 if (obj->IsClass()) { 1053 auto klass = obj->AsClass(); 1054 ArtField* fields[2] = { klass->GetSFields(), klass->GetIFields() }; 1055 size_t num_fields[2] = { klass->NumStaticFields(), klass->NumInstanceFields() }; 1056 for (size_t i = 0; i < 2; ++i) { 1057 for (size_t j = 0; j < num_fields[i]; ++j) { 1058 CHECK_EQ(fields[i][j].GetDeclaringClass(), klass); 1059 } 1060 } 1061 } 1062} 1063 1064void ClassLinker::InitFromImage() { 1065 VLOG(startup) << "ClassLinker::InitFromImage entering"; 1066 CHECK(!init_done_); 1067 1068 Runtime* const runtime = Runtime::Current(); 1069 Thread* const self = Thread::Current(); 1070 gc::Heap* const heap = runtime->GetHeap(); 1071 gc::space::ImageSpace* const space = heap->GetImageSpace(); 1072 dex_cache_image_class_lookup_required_ = true; 1073 CHECK(space != nullptr); 1074 OatFile& oat_file = GetImageOatFile(space); 1075 CHECK_EQ(oat_file.GetOatHeader().GetImageFileLocationOatChecksum(), 0U); 1076 CHECK_EQ(oat_file.GetOatHeader().GetImageFileLocationOatDataBegin(), 0U); 1077 const char* image_file_location = oat_file.GetOatHeader(). 1078 GetStoreValueByKey(OatHeader::kImageLocationKey); 1079 CHECK(image_file_location == nullptr || *image_file_location == 0); 1080 quick_resolution_trampoline_ = oat_file.GetOatHeader().GetQuickResolutionTrampoline(); 1081 quick_imt_conflict_trampoline_ = oat_file.GetOatHeader().GetQuickImtConflictTrampoline(); 1082 quick_generic_jni_trampoline_ = oat_file.GetOatHeader().GetQuickGenericJniTrampoline(); 1083 quick_to_interpreter_bridge_trampoline_ = oat_file.GetOatHeader().GetQuickToInterpreterBridge(); 1084 mirror::Object* dex_caches_object = space->GetImageHeader().GetImageRoot(ImageHeader::kDexCaches); 1085 mirror::ObjectArray<mirror::DexCache>* dex_caches = 1086 dex_caches_object->AsObjectArray<mirror::DexCache>(); 1087 1088 StackHandleScope<1> hs(self); 1089 Handle<mirror::ObjectArray<mirror::Class>> class_roots(hs.NewHandle( 1090 space->GetImageHeader().GetImageRoot(ImageHeader::kClassRoots)-> 1091 AsObjectArray<mirror::Class>())); 1092 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class>>(class_roots.Get()); 1093 1094 // Special case of setting up the String class early so that we can test arbitrary objects 1095 // as being Strings or not 1096 mirror::String::SetClass(GetClassRoot(kJavaLangString)); 1097 1098 CHECK_EQ(oat_file.GetOatHeader().GetDexFileCount(), 1099 static_cast<uint32_t>(dex_caches->GetLength())); 1100 for (int32_t i = 0; i < dex_caches->GetLength(); i++) { 1101 StackHandleScope<1> hs2(self); 1102 Handle<mirror::DexCache> dex_cache(hs2.NewHandle(dex_caches->Get(i))); 1103 const std::string& dex_file_location(dex_cache->GetLocation()->ToModifiedUtf8()); 1104 const OatFile::OatDexFile* oat_dex_file = oat_file.GetOatDexFile(dex_file_location.c_str(), 1105 nullptr); 1106 CHECK(oat_dex_file != nullptr) << oat_file.GetLocation() << " " << dex_file_location; 1107 std::string error_msg; 1108 std::unique_ptr<const DexFile> dex_file = oat_dex_file->OpenDexFile(&error_msg); 1109 if (dex_file.get() == nullptr) { 1110 LOG(FATAL) << "Failed to open dex file " << dex_file_location 1111 << " from within oat file " << oat_file.GetLocation() 1112 << " error '" << error_msg << "'"; 1113 UNREACHABLE(); 1114 } 1115 1116 CHECK_EQ(dex_file->GetLocationChecksum(), oat_dex_file->GetDexFileLocationChecksum()); 1117 1118 AppendToBootClassPath(*dex_file.get(), dex_cache); 1119 opened_dex_files_.push_back(std::move(dex_file)); 1120 } 1121 1122 // Set classes on AbstractMethod early so that IsMethod tests can be performed during the live 1123 // bitmap walk. 1124 mirror::ArtMethod::SetClass(GetClassRoot(kJavaLangReflectArtMethod)); 1125 size_t art_method_object_size = mirror::ArtMethod::GetJavaLangReflectArtMethod()->GetObjectSize(); 1126 if (!runtime->IsAotCompiler()) { 1127 // Aot compiler supports having an image with a different pointer size than the runtime. This 1128 // happens on the host for compile 32 bit tests since we use a 64 bit libart compiler. We may 1129 // also use 32 bit dex2oat on a system with 64 bit apps. 1130 CHECK_EQ(art_method_object_size, mirror::ArtMethod::InstanceSize(sizeof(void*))) 1131 << sizeof(void*); 1132 } 1133 if (art_method_object_size == mirror::ArtMethod::InstanceSize(4)) { 1134 image_pointer_size_ = 4; 1135 } else { 1136 CHECK_EQ(art_method_object_size, mirror::ArtMethod::InstanceSize(8)); 1137 image_pointer_size_ = 8; 1138 } 1139 1140 // Set entry point to interpreter if in InterpretOnly mode. 1141 if (!runtime->IsAotCompiler() && runtime->GetInstrumentation()->InterpretOnly()) { 1142 heap->VisitObjects(InitFromImageInterpretOnlyCallback, this); 1143 } 1144 if (kSanityCheckObjects) { 1145 for (int32_t i = 0; i < dex_caches->GetLength(); i++) { 1146 auto* dex_cache = dex_caches->Get(i); 1147 for (size_t j = 0; j < dex_cache->NumResolvedFields(); ++j) { 1148 auto* field = dex_cache->GetResolvedField(j, image_pointer_size_); 1149 if (field != nullptr) { 1150 CHECK(field->GetDeclaringClass()->GetClass() != nullptr); 1151 } 1152 } 1153 } 1154 heap->VisitObjects(SanityCheckObjectsCallback, nullptr); 1155 } 1156 1157 // reinit class_roots_ 1158 mirror::Class::SetClassClass(class_roots->Get(kJavaLangClass)); 1159 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class>>(class_roots.Get()); 1160 1161 // reinit array_iftable_ from any array class instance, they should be == 1162 array_iftable_ = GcRoot<mirror::IfTable>(GetClassRoot(kObjectArrayClass)->GetIfTable()); 1163 DCHECK_EQ(array_iftable_.Read(), GetClassRoot(kBooleanArrayClass)->GetIfTable()); 1164 // String class root was set above 1165 mirror::Field::SetClass(GetClassRoot(kJavaLangReflectField)); 1166 mirror::Field::SetArrayClass(GetClassRoot(kJavaLangReflectFieldArrayClass)); 1167 mirror::Constructor::SetClass(GetClassRoot(kJavaLangReflectConstructor)); 1168 mirror::Constructor::SetArrayClass(GetClassRoot(kJavaLangReflectConstructorArrayClass)); 1169 mirror::Method::SetClass(GetClassRoot(kJavaLangReflectMethod)); 1170 mirror::Method::SetArrayClass(GetClassRoot(kJavaLangReflectMethodArrayClass)); 1171 mirror::Reference::SetClass(GetClassRoot(kJavaLangRefReference)); 1172 mirror::BooleanArray::SetArrayClass(GetClassRoot(kBooleanArrayClass)); 1173 mirror::ByteArray::SetArrayClass(GetClassRoot(kByteArrayClass)); 1174 mirror::CharArray::SetArrayClass(GetClassRoot(kCharArrayClass)); 1175 mirror::DoubleArray::SetArrayClass(GetClassRoot(kDoubleArrayClass)); 1176 mirror::FloatArray::SetArrayClass(GetClassRoot(kFloatArrayClass)); 1177 mirror::IntArray::SetArrayClass(GetClassRoot(kIntArrayClass)); 1178 mirror::LongArray::SetArrayClass(GetClassRoot(kLongArrayClass)); 1179 mirror::ShortArray::SetArrayClass(GetClassRoot(kShortArrayClass)); 1180 mirror::Throwable::SetClass(GetClassRoot(kJavaLangThrowable)); 1181 mirror::StackTraceElement::SetClass(GetClassRoot(kJavaLangStackTraceElement)); 1182 1183 FinishInit(self); 1184 1185 VLOG(startup) << "ClassLinker::InitFromImage exiting"; 1186} 1187 1188void ClassLinker::VisitClassRoots(RootVisitor* visitor, VisitRootFlags flags) { 1189 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 1190 BufferedRootVisitor<kDefaultBufferedRootCount> buffered_visitor( 1191 visitor, RootInfo(kRootStickyClass)); 1192 if ((flags & kVisitRootFlagAllRoots) != 0) { 1193 for (GcRoot<mirror::Class>& root : class_table_) { 1194 buffered_visitor.VisitRoot(root); 1195 root.Read()->VisitFieldRoots(buffered_visitor); 1196 } 1197 // PreZygote classes can't move so we won't need to update fields' declaring classes. 1198 for (GcRoot<mirror::Class>& root : pre_zygote_class_table_) { 1199 buffered_visitor.VisitRoot(root); 1200 root.Read()->VisitFieldRoots(buffered_visitor); 1201 } 1202 } else if ((flags & kVisitRootFlagNewRoots) != 0) { 1203 for (auto& root : new_class_roots_) { 1204 mirror::Class* old_ref = root.Read<kWithoutReadBarrier>(); 1205 old_ref->VisitFieldRoots(buffered_visitor); 1206 root.VisitRoot(visitor, RootInfo(kRootStickyClass)); 1207 mirror::Class* new_ref = root.Read<kWithoutReadBarrier>(); 1208 if (UNLIKELY(new_ref != old_ref)) { 1209 // Uh ohes, GC moved a root in the log. Need to search the class_table and update the 1210 // corresponding object. This is slow, but luckily for us, this may only happen with a 1211 // concurrent moving GC. 1212 auto it = class_table_.Find(GcRoot<mirror::Class>(old_ref)); 1213 DCHECK(it != class_table_.end()); 1214 *it = GcRoot<mirror::Class>(new_ref); 1215 } 1216 } 1217 } 1218 buffered_visitor.Flush(); // Flush before clearing new_class_roots_. 1219 if ((flags & kVisitRootFlagClearRootLog) != 0) { 1220 new_class_roots_.clear(); 1221 } 1222 if ((flags & kVisitRootFlagStartLoggingNewRoots) != 0) { 1223 log_new_class_table_roots_ = true; 1224 } else if ((flags & kVisitRootFlagStopLoggingNewRoots) != 0) { 1225 log_new_class_table_roots_ = false; 1226 } 1227 // We deliberately ignore the class roots in the image since we 1228 // handle image roots by using the MS/CMS rescanning of dirty cards. 1229} 1230 1231// Keep in sync with InitCallback. Anything we visit, we need to 1232// reinit references to when reinitializing a ClassLinker from a 1233// mapped image. 1234void ClassLinker::VisitRoots(RootVisitor* visitor, VisitRootFlags flags) { 1235 class_roots_.VisitRoot(visitor, RootInfo(kRootVMInternal)); 1236 Thread* const self = Thread::Current(); 1237 { 1238 ReaderMutexLock mu(self, dex_lock_); 1239 if ((flags & kVisitRootFlagAllRoots) != 0) { 1240 for (GcRoot<mirror::DexCache>& dex_cache : dex_caches_) { 1241 dex_cache.VisitRoot(visitor, RootInfo(kRootVMInternal)); 1242 } 1243 } else if ((flags & kVisitRootFlagNewRoots) != 0) { 1244 for (size_t index : new_dex_cache_roots_) { 1245 dex_caches_[index].VisitRoot(visitor, RootInfo(kRootVMInternal)); 1246 } 1247 } 1248 if ((flags & kVisitRootFlagClearRootLog) != 0) { 1249 new_dex_cache_roots_.clear(); 1250 } 1251 if ((flags & kVisitRootFlagStartLoggingNewRoots) != 0) { 1252 log_new_dex_caches_roots_ = true; 1253 } else if ((flags & kVisitRootFlagStopLoggingNewRoots) != 0) { 1254 log_new_dex_caches_roots_ = false; 1255 } 1256 } 1257 VisitClassRoots(visitor, flags); 1258 array_iftable_.VisitRoot(visitor, RootInfo(kRootVMInternal)); 1259 for (size_t i = 0; i < kFindArrayCacheSize; ++i) { 1260 find_array_class_cache_[i].VisitRootIfNonNull(visitor, RootInfo(kRootVMInternal)); 1261 } 1262} 1263 1264void ClassLinker::VisitClasses(ClassVisitor* visitor, void* arg) { 1265 if (dex_cache_image_class_lookup_required_) { 1266 MoveImageClassesToClassTable(); 1267 } 1268 // TODO: why isn't this a ReaderMutexLock? 1269 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 1270 for (GcRoot<mirror::Class>& root : class_table_) { 1271 if (!visitor(root.Read(), arg)) { 1272 return; 1273 } 1274 } 1275 for (GcRoot<mirror::Class>& root : pre_zygote_class_table_) { 1276 if (!visitor(root.Read(), arg)) { 1277 return; 1278 } 1279 } 1280} 1281 1282static bool GetClassesVisitorSet(mirror::Class* c, void* arg) { 1283 std::set<mirror::Class*>* classes = reinterpret_cast<std::set<mirror::Class*>*>(arg); 1284 classes->insert(c); 1285 return true; 1286} 1287 1288struct GetClassesVisitorArrayArg { 1289 Handle<mirror::ObjectArray<mirror::Class>>* classes; 1290 int32_t index; 1291 bool success; 1292}; 1293 1294static bool GetClassesVisitorArray(mirror::Class* c, void* varg) 1295 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1296 GetClassesVisitorArrayArg* arg = reinterpret_cast<GetClassesVisitorArrayArg*>(varg); 1297 if (arg->index < (*arg->classes)->GetLength()) { 1298 (*arg->classes)->Set(arg->index, c); 1299 arg->index++; 1300 return true; 1301 } else { 1302 arg->success = false; 1303 return false; 1304 } 1305} 1306 1307void ClassLinker::VisitClassesWithoutClassesLock(ClassVisitor* visitor, void* arg) { 1308 // TODO: it may be possible to avoid secondary storage if we iterate over dex caches. The problem 1309 // is avoiding duplicates. 1310 if (!kMovingClasses) { 1311 std::set<mirror::Class*> classes; 1312 VisitClasses(GetClassesVisitorSet, &classes); 1313 for (mirror::Class* klass : classes) { 1314 if (!visitor(klass, arg)) { 1315 return; 1316 } 1317 } 1318 } else { 1319 Thread* self = Thread::Current(); 1320 StackHandleScope<1> hs(self); 1321 MutableHandle<mirror::ObjectArray<mirror::Class>> classes = 1322 hs.NewHandle<mirror::ObjectArray<mirror::Class>>(nullptr); 1323 GetClassesVisitorArrayArg local_arg; 1324 local_arg.classes = &classes; 1325 local_arg.success = false; 1326 // We size the array assuming classes won't be added to the class table during the visit. 1327 // If this assumption fails we iterate again. 1328 while (!local_arg.success) { 1329 size_t class_table_size; 1330 { 1331 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 1332 class_table_size = class_table_.Size() + pre_zygote_class_table_.Size(); 1333 } 1334 mirror::Class* class_type = mirror::Class::GetJavaLangClass(); 1335 mirror::Class* array_of_class = FindArrayClass(self, &class_type); 1336 classes.Assign( 1337 mirror::ObjectArray<mirror::Class>::Alloc(self, array_of_class, class_table_size)); 1338 CHECK(classes.Get() != nullptr); // OOME. 1339 local_arg.index = 0; 1340 local_arg.success = true; 1341 VisitClasses(GetClassesVisitorArray, &local_arg); 1342 } 1343 for (int32_t i = 0; i < classes->GetLength(); ++i) { 1344 // If the class table shrank during creation of the clases array we expect null elements. If 1345 // the class table grew then the loop repeats. If classes are created after the loop has 1346 // finished then we don't visit. 1347 mirror::Class* klass = classes->Get(i); 1348 if (klass != nullptr && !visitor(klass, arg)) { 1349 return; 1350 } 1351 } 1352 } 1353} 1354 1355ClassLinker::~ClassLinker() { 1356 mirror::ArtMethod::ResetClass(); 1357 mirror::Class::ResetClass(); 1358 mirror::Constructor::ResetClass(); 1359 mirror::Field::ResetClass(); 1360 mirror::Method::ResetClass(); 1361 mirror::Reference::ResetClass(); 1362 mirror::StackTraceElement::ResetClass(); 1363 mirror::String::ResetClass(); 1364 mirror::Throwable::ResetClass(); 1365 mirror::BooleanArray::ResetArrayClass(); 1366 mirror::ByteArray::ResetArrayClass(); 1367 mirror::CharArray::ResetArrayClass(); 1368 mirror::Constructor::ResetArrayClass(); 1369 mirror::DoubleArray::ResetArrayClass(); 1370 mirror::Field::ResetArrayClass(); 1371 mirror::FloatArray::ResetArrayClass(); 1372 mirror::Method::ResetArrayClass(); 1373 mirror::IntArray::ResetArrayClass(); 1374 mirror::LongArray::ResetArrayClass(); 1375 mirror::ShortArray::ResetArrayClass(); 1376 STLDeleteElements(&oat_files_); 1377} 1378 1379mirror::DexCache* ClassLinker::AllocDexCache(Thread* self, const DexFile& dex_file) { 1380 gc::Heap* const heap = Runtime::Current()->GetHeap(); 1381 StackHandleScope<16> hs(self); 1382 Handle<mirror::Class> dex_cache_class(hs.NewHandle(GetClassRoot(kJavaLangDexCache))); 1383 Handle<mirror::DexCache> dex_cache( 1384 hs.NewHandle(down_cast<mirror::DexCache*>( 1385 heap->AllocObject<true>(self, dex_cache_class.Get(), dex_cache_class->GetObjectSize(), 1386 VoidFunctor())))); 1387 if (dex_cache.Get() == nullptr) { 1388 return nullptr; 1389 } 1390 Handle<mirror::String> 1391 location(hs.NewHandle(intern_table_->InternStrong(dex_file.GetLocation().c_str()))); 1392 if (location.Get() == nullptr) { 1393 return nullptr; 1394 } 1395 Handle<mirror::ObjectArray<mirror::String>> 1396 strings(hs.NewHandle(AllocStringArray(self, dex_file.NumStringIds()))); 1397 if (strings.Get() == nullptr) { 1398 return nullptr; 1399 } 1400 Handle<mirror::ObjectArray<mirror::Class>> 1401 types(hs.NewHandle(AllocClassArray(self, dex_file.NumTypeIds()))); 1402 if (types.Get() == nullptr) { 1403 return nullptr; 1404 } 1405 Handle<mirror::ObjectArray<mirror::ArtMethod>> 1406 methods(hs.NewHandle(AllocArtMethodArray(self, dex_file.NumMethodIds()))); 1407 if (methods.Get() == nullptr) { 1408 return nullptr; 1409 } 1410 Handle<mirror::Array> fields; 1411 if (image_pointer_size_ == 8) { 1412 fields = hs.NewHandle<mirror::Array>(mirror::LongArray::Alloc(self, dex_file.NumFieldIds())); 1413 } else { 1414 fields = hs.NewHandle<mirror::Array>(mirror::IntArray::Alloc(self, dex_file.NumFieldIds())); 1415 } 1416 if (fields.Get() == nullptr) { 1417 return nullptr; 1418 } 1419 dex_cache->Init(&dex_file, location.Get(), strings.Get(), types.Get(), methods.Get(), 1420 fields.Get()); 1421 return dex_cache.Get(); 1422} 1423 1424mirror::Class* ClassLinker::AllocClass(Thread* self, mirror::Class* java_lang_Class, 1425 uint32_t class_size) { 1426 DCHECK_GE(class_size, sizeof(mirror::Class)); 1427 gc::Heap* heap = Runtime::Current()->GetHeap(); 1428 mirror::Class::InitializeClassVisitor visitor(class_size); 1429 mirror::Object* k = kMovingClasses ? 1430 heap->AllocObject<true>(self, java_lang_Class, class_size, visitor) : 1431 heap->AllocNonMovableObject<true>(self, java_lang_Class, class_size, visitor); 1432 if (UNLIKELY(k == nullptr)) { 1433 CHECK(self->IsExceptionPending()); // OOME. 1434 return nullptr; 1435 } 1436 return k->AsClass(); 1437} 1438 1439mirror::Class* ClassLinker::AllocClass(Thread* self, uint32_t class_size) { 1440 return AllocClass(self, GetClassRoot(kJavaLangClass), class_size); 1441} 1442 1443mirror::ArtMethod* ClassLinker::AllocArtMethod(Thread* self) { 1444 return down_cast<mirror::ArtMethod*>( 1445 GetClassRoot(kJavaLangReflectArtMethod)->AllocNonMovableObject(self)); 1446} 1447 1448mirror::ObjectArray<mirror::StackTraceElement>* ClassLinker::AllocStackTraceElementArray( 1449 Thread* self, size_t length) { 1450 return mirror::ObjectArray<mirror::StackTraceElement>::Alloc( 1451 self, GetClassRoot(kJavaLangStackTraceElementArrayClass), length); 1452} 1453 1454mirror::Class* ClassLinker::EnsureResolved(Thread* self, const char* descriptor, 1455 mirror::Class* klass) { 1456 DCHECK(klass != nullptr); 1457 1458 // For temporary classes we must wait for them to be retired. 1459 if (init_done_ && klass->IsTemp()) { 1460 CHECK(!klass->IsResolved()); 1461 if (klass->IsErroneous()) { 1462 ThrowEarlierClassFailure(klass); 1463 return nullptr; 1464 } 1465 StackHandleScope<1> hs(self); 1466 Handle<mirror::Class> h_class(hs.NewHandle(klass)); 1467 ObjectLock<mirror::Class> lock(self, h_class); 1468 // Loop and wait for the resolving thread to retire this class. 1469 while (!h_class->IsRetired() && !h_class->IsErroneous()) { 1470 lock.WaitIgnoringInterrupts(); 1471 } 1472 if (h_class->IsErroneous()) { 1473 ThrowEarlierClassFailure(h_class.Get()); 1474 return nullptr; 1475 } 1476 CHECK(h_class->IsRetired()); 1477 // Get the updated class from class table. 1478 klass = LookupClass(self, descriptor, ComputeModifiedUtf8Hash(descriptor), 1479 h_class.Get()->GetClassLoader()); 1480 } 1481 1482 // Wait for the class if it has not already been linked. 1483 if (!klass->IsResolved() && !klass->IsErroneous()) { 1484 StackHandleScope<1> hs(self); 1485 HandleWrapper<mirror::Class> h_class(hs.NewHandleWrapper(&klass)); 1486 ObjectLock<mirror::Class> lock(self, h_class); 1487 // Check for circular dependencies between classes. 1488 if (!h_class->IsResolved() && h_class->GetClinitThreadId() == self->GetTid()) { 1489 ThrowClassCircularityError(h_class.Get()); 1490 mirror::Class::SetStatus(h_class, mirror::Class::kStatusError, self); 1491 return nullptr; 1492 } 1493 // Wait for the pending initialization to complete. 1494 while (!h_class->IsResolved() && !h_class->IsErroneous()) { 1495 lock.WaitIgnoringInterrupts(); 1496 } 1497 } 1498 1499 if (klass->IsErroneous()) { 1500 ThrowEarlierClassFailure(klass); 1501 return nullptr; 1502 } 1503 // Return the loaded class. No exceptions should be pending. 1504 CHECK(klass->IsResolved()) << PrettyClass(klass); 1505 self->AssertNoPendingException(); 1506 return klass; 1507} 1508 1509typedef std::pair<const DexFile*, const DexFile::ClassDef*> ClassPathEntry; 1510 1511// Search a collection of DexFiles for a descriptor 1512ClassPathEntry FindInClassPath(const char* descriptor, 1513 size_t hash, const std::vector<const DexFile*>& class_path) { 1514 for (const DexFile* dex_file : class_path) { 1515 const DexFile::ClassDef* dex_class_def = dex_file->FindClassDef(descriptor, hash); 1516 if (dex_class_def != nullptr) { 1517 return ClassPathEntry(dex_file, dex_class_def); 1518 } 1519 } 1520 return ClassPathEntry(nullptr, nullptr); 1521} 1522 1523static bool IsBootClassLoader(ScopedObjectAccessAlreadyRunnable& soa, 1524 mirror::ClassLoader* class_loader) 1525 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1526 return class_loader == nullptr || 1527 class_loader->GetClass() == 1528 soa.Decode<mirror::Class*>(WellKnownClasses::java_lang_BootClassLoader); 1529} 1530 1531bool ClassLinker::FindClassInPathClassLoader(ScopedObjectAccessAlreadyRunnable& soa, 1532 Thread* self, const char* descriptor, 1533 size_t hash, 1534 Handle<mirror::ClassLoader> class_loader, 1535 mirror::Class** result) { 1536 // Termination case: boot class-loader. 1537 if (IsBootClassLoader(soa, class_loader.Get())) { 1538 // The boot class loader, search the boot class path. 1539 ClassPathEntry pair = FindInClassPath(descriptor, hash, boot_class_path_); 1540 if (pair.second != nullptr) { 1541 mirror::Class* klass = LookupClass(self, descriptor, hash, nullptr); 1542 if (klass != nullptr) { 1543 *result = EnsureResolved(self, descriptor, klass); 1544 } else { 1545 *result = DefineClass(self, descriptor, hash, NullHandle<mirror::ClassLoader>(), 1546 *pair.first, *pair.second); 1547 } 1548 if (*result == nullptr) { 1549 CHECK(self->IsExceptionPending()) << descriptor; 1550 self->ClearException(); 1551 } 1552 } else { 1553 *result = nullptr; 1554 } 1555 return true; 1556 } 1557 1558 // Unsupported class-loader? 1559 if (class_loader->GetClass() != 1560 soa.Decode<mirror::Class*>(WellKnownClasses::dalvik_system_PathClassLoader)) { 1561 *result = nullptr; 1562 return false; 1563 } 1564 1565 // Handles as RegisterDexFile may allocate dex caches (and cause thread suspension). 1566 StackHandleScope<4> hs(self); 1567 Handle<mirror::ClassLoader> h_parent(hs.NewHandle(class_loader->GetParent())); 1568 bool recursive_result = FindClassInPathClassLoader(soa, self, descriptor, hash, h_parent, result); 1569 1570 if (!recursive_result) { 1571 // Something wrong up the chain. 1572 return false; 1573 } 1574 1575 if (*result != nullptr) { 1576 // Found the class up the chain. 1577 return true; 1578 } 1579 1580 // Handle this step. 1581 // Handle as if this is the child PathClassLoader. 1582 // The class loader is a PathClassLoader which inherits from BaseDexClassLoader. 1583 // We need to get the DexPathList and loop through it. 1584 ArtField* const cookie_field = soa.DecodeField(WellKnownClasses::dalvik_system_DexFile_cookie); 1585 ArtField* const dex_file_field = 1586 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList__Element_dexFile); 1587 mirror::Object* dex_path_list = 1588 soa.DecodeField(WellKnownClasses::dalvik_system_PathClassLoader_pathList)-> 1589 GetObject(class_loader.Get()); 1590 if (dex_path_list != nullptr && dex_file_field != nullptr && cookie_field != nullptr) { 1591 // DexPathList has an array dexElements of Elements[] which each contain a dex file. 1592 mirror::Object* dex_elements_obj = 1593 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList_dexElements)-> 1594 GetObject(dex_path_list); 1595 // Loop through each dalvik.system.DexPathList$Element's dalvik.system.DexFile and look 1596 // at the mCookie which is a DexFile vector. 1597 if (dex_elements_obj != nullptr) { 1598 Handle<mirror::ObjectArray<mirror::Object>> dex_elements = 1599 hs.NewHandle(dex_elements_obj->AsObjectArray<mirror::Object>()); 1600 for (int32_t i = 0; i < dex_elements->GetLength(); ++i) { 1601 mirror::Object* element = dex_elements->GetWithoutChecks(i); 1602 if (element == nullptr) { 1603 // Should never happen, fall back to java code to throw a NPE. 1604 break; 1605 } 1606 mirror::Object* dex_file = dex_file_field->GetObject(element); 1607 if (dex_file != nullptr) { 1608 mirror::LongArray* long_array = cookie_field->GetObject(dex_file)->AsLongArray(); 1609 if (long_array == nullptr) { 1610 // This should never happen so log a warning. 1611 LOG(WARNING) << "Null DexFile::mCookie for " << descriptor; 1612 break; 1613 } 1614 int32_t long_array_size = long_array->GetLength(); 1615 for (int32_t j = 0; j < long_array_size; ++j) { 1616 const DexFile* cp_dex_file = reinterpret_cast<const DexFile*>(static_cast<uintptr_t>( 1617 long_array->GetWithoutChecks(j))); 1618 const DexFile::ClassDef* dex_class_def = cp_dex_file->FindClassDef(descriptor, hash); 1619 if (dex_class_def != nullptr) { 1620 RegisterDexFile(*cp_dex_file); 1621 mirror::Class* klass = DefineClass(self, descriptor, hash, class_loader, 1622 *cp_dex_file, *dex_class_def); 1623 if (klass == nullptr) { 1624 CHECK(self->IsExceptionPending()) << descriptor; 1625 self->ClearException(); 1626 // TODO: Is it really right to break here, and not check the other dex files? 1627 return true; 1628 } 1629 *result = klass; 1630 return true; 1631 } 1632 } 1633 } 1634 } 1635 } 1636 self->AssertNoPendingException(); 1637 } 1638 1639 // Result is still null from the parent call, no need to set it again... 1640 return true; 1641} 1642 1643mirror::Class* ClassLinker::FindClass(Thread* self, const char* descriptor, 1644 Handle<mirror::ClassLoader> class_loader) { 1645 DCHECK_NE(*descriptor, '\0') << "descriptor is empty string"; 1646 DCHECK(self != nullptr); 1647 self->AssertNoPendingException(); 1648 if (descriptor[1] == '\0') { 1649 // only the descriptors of primitive types should be 1 character long, also avoid class lookup 1650 // for primitive classes that aren't backed by dex files. 1651 return FindPrimitiveClass(descriptor[0]); 1652 } 1653 const size_t hash = ComputeModifiedUtf8Hash(descriptor); 1654 // Find the class in the loaded classes table. 1655 mirror::Class* klass = LookupClass(self, descriptor, hash, class_loader.Get()); 1656 if (klass != nullptr) { 1657 return EnsureResolved(self, descriptor, klass); 1658 } 1659 // Class is not yet loaded. 1660 if (descriptor[0] == '[') { 1661 return CreateArrayClass(self, descriptor, hash, class_loader); 1662 } else if (class_loader.Get() == nullptr) { 1663 // The boot class loader, search the boot class path. 1664 ClassPathEntry pair = FindInClassPath(descriptor, hash, boot_class_path_); 1665 if (pair.second != nullptr) { 1666 return DefineClass(self, descriptor, hash, NullHandle<mirror::ClassLoader>(), *pair.first, 1667 *pair.second); 1668 } else { 1669 // The boot class loader is searched ahead of the application class loader, failures are 1670 // expected and will be wrapped in a ClassNotFoundException. Use the pre-allocated error to 1671 // trigger the chaining with a proper stack trace. 1672 mirror::Throwable* pre_allocated = Runtime::Current()->GetPreAllocatedNoClassDefFoundError(); 1673 self->SetException(pre_allocated); 1674 return nullptr; 1675 } 1676 } else { 1677 ScopedObjectAccessUnchecked soa(self); 1678 mirror::Class* cp_klass; 1679 if (FindClassInPathClassLoader(soa, self, descriptor, hash, class_loader, &cp_klass)) { 1680 // The chain was understood. So the value in cp_klass is either the class we were looking 1681 // for, or not found. 1682 if (cp_klass != nullptr) { 1683 return cp_klass; 1684 } 1685 // TODO: We handle the boot classpath loader in FindClassInPathClassLoader. Try to unify this 1686 // and the branch above. TODO: throw the right exception here. 1687 1688 // We'll let the Java-side rediscover all this and throw the exception with the right stack 1689 // trace. 1690 } 1691 1692 if (Runtime::Current()->IsAotCompiler()) { 1693 // Oops, compile-time, can't run actual class-loader code. 1694 mirror::Throwable* pre_allocated = Runtime::Current()->GetPreAllocatedNoClassDefFoundError(); 1695 self->SetException(pre_allocated); 1696 return nullptr; 1697 } 1698 1699 ScopedLocalRef<jobject> class_loader_object(soa.Env(), 1700 soa.AddLocalReference<jobject>(class_loader.Get())); 1701 std::string class_name_string(DescriptorToDot(descriptor)); 1702 ScopedLocalRef<jobject> result(soa.Env(), nullptr); 1703 { 1704 ScopedThreadStateChange tsc(self, kNative); 1705 ScopedLocalRef<jobject> class_name_object(soa.Env(), 1706 soa.Env()->NewStringUTF(class_name_string.c_str())); 1707 if (class_name_object.get() == nullptr) { 1708 DCHECK(self->IsExceptionPending()); // OOME. 1709 return nullptr; 1710 } 1711 CHECK(class_loader_object.get() != nullptr); 1712 result.reset(soa.Env()->CallObjectMethod(class_loader_object.get(), 1713 WellKnownClasses::java_lang_ClassLoader_loadClass, 1714 class_name_object.get())); 1715 } 1716 if (self->IsExceptionPending()) { 1717 // If the ClassLoader threw, pass that exception up. 1718 return nullptr; 1719 } else if (result.get() == nullptr) { 1720 // broken loader - throw NPE to be compatible with Dalvik 1721 ThrowNullPointerException(StringPrintf("ClassLoader.loadClass returned null for %s", 1722 class_name_string.c_str()).c_str()); 1723 return nullptr; 1724 } else { 1725 // success, return mirror::Class* 1726 return soa.Decode<mirror::Class*>(result.get()); 1727 } 1728 } 1729 UNREACHABLE(); 1730} 1731 1732mirror::Class* ClassLinker::DefineClass(Thread* self, const char* descriptor, size_t hash, 1733 Handle<mirror::ClassLoader> class_loader, 1734 const DexFile& dex_file, 1735 const DexFile::ClassDef& dex_class_def) { 1736 StackHandleScope<3> hs(self); 1737 auto klass = hs.NewHandle<mirror::Class>(nullptr); 1738 1739 // Load the class from the dex file. 1740 if (UNLIKELY(!init_done_)) { 1741 // finish up init of hand crafted class_roots_ 1742 if (strcmp(descriptor, "Ljava/lang/Object;") == 0) { 1743 klass.Assign(GetClassRoot(kJavaLangObject)); 1744 } else if (strcmp(descriptor, "Ljava/lang/Class;") == 0) { 1745 klass.Assign(GetClassRoot(kJavaLangClass)); 1746 } else if (strcmp(descriptor, "Ljava/lang/String;") == 0) { 1747 klass.Assign(GetClassRoot(kJavaLangString)); 1748 } else if (strcmp(descriptor, "Ljava/lang/ref/Reference;") == 0) { 1749 klass.Assign(GetClassRoot(kJavaLangRefReference)); 1750 } else if (strcmp(descriptor, "Ljava/lang/DexCache;") == 0) { 1751 klass.Assign(GetClassRoot(kJavaLangDexCache)); 1752 } else if (strcmp(descriptor, "Ljava/lang/reflect/ArtMethod;") == 0) { 1753 klass.Assign(GetClassRoot(kJavaLangReflectArtMethod)); 1754 } 1755 } 1756 1757 if (klass.Get() == nullptr) { 1758 // Allocate a class with the status of not ready. 1759 // Interface object should get the right size here. Regular class will 1760 // figure out the right size later and be replaced with one of the right 1761 // size when the class becomes resolved. 1762 klass.Assign(AllocClass(self, SizeOfClassWithoutEmbeddedTables(dex_file, dex_class_def))); 1763 } 1764 if (UNLIKELY(klass.Get() == nullptr)) { 1765 CHECK(self->IsExceptionPending()); // Expect an OOME. 1766 return nullptr; 1767 } 1768 klass->SetDexCache(FindDexCache(dex_file)); 1769 1770 SetupClass(dex_file, dex_class_def, klass, class_loader.Get()); 1771 1772 // Mark the string class by setting its access flag. 1773 if (UNLIKELY(!init_done_)) { 1774 if (strcmp(descriptor, "Ljava/lang/String;") == 0) { 1775 klass->SetStringClass(); 1776 } 1777 } 1778 1779 ObjectLock<mirror::Class> lock(self, klass); 1780 klass->SetClinitThreadId(self->GetTid()); 1781 1782 // Add the newly loaded class to the loaded classes table. 1783 mirror::Class* existing = InsertClass(descriptor, klass.Get(), hash); 1784 if (existing != nullptr) { 1785 // We failed to insert because we raced with another thread. Calling EnsureResolved may cause 1786 // this thread to block. 1787 return EnsureResolved(self, descriptor, existing); 1788 } 1789 1790 // Load the fields and other things after we are inserted in the table. This is so that we don't 1791 // end up allocating unfree-able linear alloc resources and then lose the race condition. The 1792 // other reason is that the field roots are only visited from the class table. So we need to be 1793 // inserted before we allocate / fill in these fields. 1794 LoadClass(self, dex_file, dex_class_def, klass); 1795 if (self->IsExceptionPending()) { 1796 // An exception occured during load, set status to erroneous while holding klass' lock in case 1797 // notification is necessary. 1798 if (!klass->IsErroneous()) { 1799 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 1800 } 1801 return nullptr; 1802 } 1803 1804 // Finish loading (if necessary) by finding parents 1805 CHECK(!klass->IsLoaded()); 1806 if (!LoadSuperAndInterfaces(klass, dex_file)) { 1807 // Loading failed. 1808 if (!klass->IsErroneous()) { 1809 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 1810 } 1811 return nullptr; 1812 } 1813 CHECK(klass->IsLoaded()); 1814 // Link the class (if necessary) 1815 CHECK(!klass->IsResolved()); 1816 // TODO: Use fast jobjects? 1817 auto interfaces = hs.NewHandle<mirror::ObjectArray<mirror::Class>>(nullptr); 1818 1819 MutableHandle<mirror::Class> h_new_class = hs.NewHandle<mirror::Class>(nullptr); 1820 if (!LinkClass(self, descriptor, klass, interfaces, &h_new_class)) { 1821 // Linking failed. 1822 if (!klass->IsErroneous()) { 1823 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 1824 } 1825 return nullptr; 1826 } 1827 self->AssertNoPendingException(); 1828 CHECK(h_new_class.Get() != nullptr) << descriptor; 1829 CHECK(h_new_class->IsResolved()) << descriptor; 1830 1831 // Instrumentation may have updated entrypoints for all methods of all 1832 // classes. However it could not update methods of this class while we 1833 // were loading it. Now the class is resolved, we can update entrypoints 1834 // as required by instrumentation. 1835 if (Runtime::Current()->GetInstrumentation()->AreExitStubsInstalled()) { 1836 // We must be in the kRunnable state to prevent instrumentation from 1837 // suspending all threads to update entrypoints while we are doing it 1838 // for this class. 1839 DCHECK_EQ(self->GetState(), kRunnable); 1840 Runtime::Current()->GetInstrumentation()->InstallStubsForClass(h_new_class.Get()); 1841 } 1842 1843 /* 1844 * We send CLASS_PREPARE events to the debugger from here. The 1845 * definition of "preparation" is creating the static fields for a 1846 * class and initializing them to the standard default values, but not 1847 * executing any code (that comes later, during "initialization"). 1848 * 1849 * We did the static preparation in LinkClass. 1850 * 1851 * The class has been prepared and resolved but possibly not yet verified 1852 * at this point. 1853 */ 1854 Dbg::PostClassPrepare(h_new_class.Get()); 1855 1856 return h_new_class.Get(); 1857} 1858 1859uint32_t ClassLinker::SizeOfClassWithoutEmbeddedTables(const DexFile& dex_file, 1860 const DexFile::ClassDef& dex_class_def) { 1861 const uint8_t* class_data = dex_file.GetClassData(dex_class_def); 1862 size_t num_ref = 0; 1863 size_t num_8 = 0; 1864 size_t num_16 = 0; 1865 size_t num_32 = 0; 1866 size_t num_64 = 0; 1867 if (class_data != nullptr) { 1868 for (ClassDataItemIterator it(dex_file, class_data); it.HasNextStaticField(); it.Next()) { 1869 const DexFile::FieldId& field_id = dex_file.GetFieldId(it.GetMemberIndex()); 1870 const char* descriptor = dex_file.GetFieldTypeDescriptor(field_id); 1871 char c = descriptor[0]; 1872 switch (c) { 1873 case 'L': 1874 case '[': 1875 num_ref++; 1876 break; 1877 case 'J': 1878 case 'D': 1879 num_64++; 1880 break; 1881 case 'I': 1882 case 'F': 1883 num_32++; 1884 break; 1885 case 'S': 1886 case 'C': 1887 num_16++; 1888 break; 1889 case 'B': 1890 case 'Z': 1891 num_8++; 1892 break; 1893 default: 1894 LOG(FATAL) << "Unknown descriptor: " << c; 1895 UNREACHABLE(); 1896 } 1897 } 1898 } 1899 return mirror::Class::ComputeClassSize(false, 0, num_8, num_16, num_32, num_64, num_ref); 1900} 1901 1902OatFile::OatClass ClassLinker::FindOatClass(const DexFile& dex_file, uint16_t class_def_idx, 1903 bool* found) { 1904 DCHECK_NE(class_def_idx, DexFile::kDexNoIndex16); 1905 const OatFile::OatDexFile* oat_dex_file = dex_file.GetOatDexFile(); 1906 if (oat_dex_file == nullptr) { 1907 *found = false; 1908 return OatFile::OatClass::Invalid(); 1909 } 1910 *found = true; 1911 return oat_dex_file->GetOatClass(class_def_idx); 1912} 1913 1914static uint32_t GetOatMethodIndexFromMethodIndex(const DexFile& dex_file, uint16_t class_def_idx, 1915 uint32_t method_idx) { 1916 const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_idx); 1917 const uint8_t* class_data = dex_file.GetClassData(class_def); 1918 CHECK(class_data != nullptr); 1919 ClassDataItemIterator it(dex_file, class_data); 1920 // Skip fields 1921 while (it.HasNextStaticField()) { 1922 it.Next(); 1923 } 1924 while (it.HasNextInstanceField()) { 1925 it.Next(); 1926 } 1927 // Process methods 1928 size_t class_def_method_index = 0; 1929 while (it.HasNextDirectMethod()) { 1930 if (it.GetMemberIndex() == method_idx) { 1931 return class_def_method_index; 1932 } 1933 class_def_method_index++; 1934 it.Next(); 1935 } 1936 while (it.HasNextVirtualMethod()) { 1937 if (it.GetMemberIndex() == method_idx) { 1938 return class_def_method_index; 1939 } 1940 class_def_method_index++; 1941 it.Next(); 1942 } 1943 DCHECK(!it.HasNext()); 1944 LOG(FATAL) << "Failed to find method index " << method_idx << " in " << dex_file.GetLocation(); 1945 UNREACHABLE(); 1946} 1947 1948const OatFile::OatMethod ClassLinker::FindOatMethodFor(mirror::ArtMethod* method, bool* found) { 1949 // Although we overwrite the trampoline of non-static methods, we may get here via the resolution 1950 // method for direct methods (or virtual methods made direct). 1951 mirror::Class* declaring_class = method->GetDeclaringClass(); 1952 size_t oat_method_index; 1953 if (method->IsStatic() || method->IsDirect()) { 1954 // Simple case where the oat method index was stashed at load time. 1955 oat_method_index = method->GetMethodIndex(); 1956 } else { 1957 // We're invoking a virtual method directly (thanks to sharpening), compute the oat_method_index 1958 // by search for its position in the declared virtual methods. 1959 oat_method_index = declaring_class->NumDirectMethods(); 1960 size_t end = declaring_class->NumVirtualMethods(); 1961 bool found_virtual = false; 1962 for (size_t i = 0; i < end; i++) { 1963 // Check method index instead of identity in case of duplicate method definitions. 1964 if (method->GetDexMethodIndex() == 1965 declaring_class->GetVirtualMethod(i)->GetDexMethodIndex()) { 1966 found_virtual = true; 1967 break; 1968 } 1969 oat_method_index++; 1970 } 1971 CHECK(found_virtual) << "Didn't find oat method index for virtual method: " 1972 << PrettyMethod(method); 1973 } 1974 DCHECK_EQ(oat_method_index, 1975 GetOatMethodIndexFromMethodIndex(*declaring_class->GetDexCache()->GetDexFile(), 1976 method->GetDeclaringClass()->GetDexClassDefIndex(), 1977 method->GetDexMethodIndex())); 1978 OatFile::OatClass oat_class = FindOatClass(*declaring_class->GetDexCache()->GetDexFile(), 1979 declaring_class->GetDexClassDefIndex(), 1980 found); 1981 if (!(*found)) { 1982 return OatFile::OatMethod::Invalid(); 1983 } 1984 return oat_class.GetOatMethod(oat_method_index); 1985} 1986 1987// Special case to get oat code without overwriting a trampoline. 1988const void* ClassLinker::GetQuickOatCodeFor(mirror::ArtMethod* method) { 1989 CHECK(!method->IsAbstract()) << PrettyMethod(method); 1990 if (method->IsProxyMethod()) { 1991 return GetQuickProxyInvokeHandler(); 1992 } 1993 bool found; 1994 OatFile::OatMethod oat_method = FindOatMethodFor(method, &found); 1995 if (found) { 1996 auto* code = oat_method.GetQuickCode(); 1997 if (code != nullptr) { 1998 return code; 1999 } 2000 } 2001 jit::Jit* const jit = Runtime::Current()->GetJit(); 2002 if (jit != nullptr) { 2003 auto* code = jit->GetCodeCache()->GetCodeFor(method); 2004 if (code != nullptr) { 2005 return code; 2006 } 2007 } 2008 if (method->IsNative()) { 2009 // No code and native? Use generic trampoline. 2010 return GetQuickGenericJniStub(); 2011 } 2012 return GetQuickToInterpreterBridge(); 2013} 2014 2015const void* ClassLinker::GetOatMethodQuickCodeFor(mirror::ArtMethod* method) { 2016 if (method->IsNative() || method->IsAbstract() || method->IsProxyMethod()) { 2017 return nullptr; 2018 } 2019 bool found; 2020 OatFile::OatMethod oat_method = FindOatMethodFor(method, &found); 2021 if (found) { 2022 return oat_method.GetQuickCode(); 2023 } 2024 jit::Jit* jit = Runtime::Current()->GetJit(); 2025 if (jit != nullptr) { 2026 auto* code = jit->GetCodeCache()->GetCodeFor(method); 2027 if (code != nullptr) { 2028 return code; 2029 } 2030 } 2031 return nullptr; 2032} 2033 2034const void* ClassLinker::GetQuickOatCodeFor(const DexFile& dex_file, uint16_t class_def_idx, 2035 uint32_t method_idx) { 2036 bool found; 2037 OatFile::OatClass oat_class = FindOatClass(dex_file, class_def_idx, &found); 2038 if (!found) { 2039 return nullptr; 2040 } 2041 uint32_t oat_method_idx = GetOatMethodIndexFromMethodIndex(dex_file, class_def_idx, method_idx); 2042 return oat_class.GetOatMethod(oat_method_idx).GetQuickCode(); 2043} 2044 2045// Returns true if the method must run with interpreter, false otherwise. 2046static bool NeedsInterpreter(mirror::ArtMethod* method, const void* quick_code) 2047 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 2048 if (quick_code == nullptr) { 2049 // No code: need interpreter. 2050 // May return true for native code, in the case of generic JNI 2051 // DCHECK(!method->IsNative()); 2052 return true; 2053 } 2054 // If interpreter mode is enabled, every method (except native and proxy) must 2055 // be run with interpreter. 2056 return Runtime::Current()->GetInstrumentation()->InterpretOnly() && 2057 !method->IsNative() && !method->IsProxyMethod(); 2058} 2059 2060void ClassLinker::FixupStaticTrampolines(mirror::Class* klass) { 2061 DCHECK(klass->IsInitialized()) << PrettyDescriptor(klass); 2062 if (klass->NumDirectMethods() == 0) { 2063 return; // No direct methods => no static methods. 2064 } 2065 Runtime* runtime = Runtime::Current(); 2066 if (!runtime->IsStarted()) { 2067 if (runtime->IsAotCompiler() || runtime->GetHeap()->HasImageSpace()) { 2068 return; // OAT file unavailable. 2069 } 2070 } 2071 2072 const DexFile& dex_file = klass->GetDexFile(); 2073 const DexFile::ClassDef* dex_class_def = klass->GetClassDef(); 2074 CHECK(dex_class_def != nullptr); 2075 const uint8_t* class_data = dex_file.GetClassData(*dex_class_def); 2076 // There should always be class data if there were direct methods. 2077 CHECK(class_data != nullptr) << PrettyDescriptor(klass); 2078 ClassDataItemIterator it(dex_file, class_data); 2079 // Skip fields 2080 while (it.HasNextStaticField()) { 2081 it.Next(); 2082 } 2083 while (it.HasNextInstanceField()) { 2084 it.Next(); 2085 } 2086 bool has_oat_class; 2087 OatFile::OatClass oat_class = FindOatClass(dex_file, klass->GetDexClassDefIndex(), 2088 &has_oat_class); 2089 // Link the code of methods skipped by LinkCode. 2090 for (size_t method_index = 0; it.HasNextDirectMethod(); ++method_index, it.Next()) { 2091 mirror::ArtMethod* method = klass->GetDirectMethod(method_index); 2092 if (!method->IsStatic()) { 2093 // Only update static methods. 2094 continue; 2095 } 2096 const void* quick_code = nullptr; 2097 if (has_oat_class) { 2098 OatFile::OatMethod oat_method = oat_class.GetOatMethod(method_index); 2099 quick_code = oat_method.GetQuickCode(); 2100 } 2101 const bool enter_interpreter = NeedsInterpreter(method, quick_code); 2102 if (enter_interpreter) { 2103 // Use interpreter entry point. 2104 // Check whether the method is native, in which case it's generic JNI. 2105 if (quick_code == nullptr && method->IsNative()) { 2106 quick_code = GetQuickGenericJniStub(); 2107 } else { 2108 quick_code = GetQuickToInterpreterBridge(); 2109 } 2110 } 2111 runtime->GetInstrumentation()->UpdateMethodsCode(method, quick_code); 2112 } 2113 // Ignore virtual methods on the iterator. 2114} 2115 2116void ClassLinker::LinkCode(Handle<mirror::ArtMethod> method, 2117 const OatFile::OatClass* oat_class, 2118 uint32_t class_def_method_index) { 2119 Runtime* runtime = Runtime::Current(); 2120 if (runtime->IsAotCompiler()) { 2121 // The following code only applies to a non-compiler runtime. 2122 return; 2123 } 2124 // Method shouldn't have already been linked. 2125 DCHECK(method->GetEntryPointFromQuickCompiledCode() == nullptr); 2126 if (oat_class != nullptr) { 2127 // Every kind of method should at least get an invoke stub from the oat_method. 2128 // non-abstract methods also get their code pointers. 2129 const OatFile::OatMethod oat_method = oat_class->GetOatMethod(class_def_method_index); 2130 oat_method.LinkMethod(method.Get()); 2131 } 2132 2133 // Install entry point from interpreter. 2134 bool enter_interpreter = NeedsInterpreter(method.Get(), 2135 method->GetEntryPointFromQuickCompiledCode()); 2136 if (enter_interpreter && !method->IsNative()) { 2137 method->SetEntryPointFromInterpreter(artInterpreterToInterpreterBridge); 2138 } else { 2139 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 2140 } 2141 2142 if (method->IsAbstract()) { 2143 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge()); 2144 return; 2145 } 2146 2147 if (method->IsStatic() && !method->IsConstructor()) { 2148 // For static methods excluding the class initializer, install the trampoline. 2149 // It will be replaced by the proper entry point by ClassLinker::FixupStaticTrampolines 2150 // after initializing class (see ClassLinker::InitializeClass method). 2151 method->SetEntryPointFromQuickCompiledCode(GetQuickResolutionStub()); 2152 } else if (enter_interpreter) { 2153 if (!method->IsNative()) { 2154 // Set entry point from compiled code if there's no code or in interpreter only mode. 2155 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge()); 2156 } else { 2157 method->SetEntryPointFromQuickCompiledCode(GetQuickGenericJniStub()); 2158 } 2159 } 2160 2161 if (method->IsNative()) { 2162 // Unregistering restores the dlsym lookup stub. 2163 method->UnregisterNative(); 2164 2165 if (enter_interpreter) { 2166 // We have a native method here without code. Then it should have either the generic JNI 2167 // trampoline as entrypoint (non-static), or the resolution trampoline (static). 2168 // TODO: this doesn't handle all the cases where trampolines may be installed. 2169 const void* entry_point = method->GetEntryPointFromQuickCompiledCode(); 2170 DCHECK(IsQuickGenericJniStub(entry_point) || IsQuickResolutionStub(entry_point)); 2171 } 2172 } 2173} 2174 2175void ClassLinker::SetupClass(const DexFile& dex_file, const DexFile::ClassDef& dex_class_def, 2176 Handle<mirror::Class> klass, mirror::ClassLoader* class_loader) { 2177 CHECK(klass.Get() != nullptr); 2178 CHECK(klass->GetDexCache() != nullptr); 2179 CHECK_EQ(mirror::Class::kStatusNotReady, klass->GetStatus()); 2180 const char* descriptor = dex_file.GetClassDescriptor(dex_class_def); 2181 CHECK(descriptor != nullptr); 2182 2183 klass->SetClass(GetClassRoot(kJavaLangClass)); 2184 uint32_t access_flags = dex_class_def.GetJavaAccessFlags(); 2185 CHECK_EQ(access_flags & ~kAccJavaFlagsMask, 0U); 2186 klass->SetAccessFlags(access_flags); 2187 klass->SetClassLoader(class_loader); 2188 DCHECK_EQ(klass->GetPrimitiveType(), Primitive::kPrimNot); 2189 mirror::Class::SetStatus(klass, mirror::Class::kStatusIdx, nullptr); 2190 2191 klass->SetDexClassDefIndex(dex_file.GetIndexForClassDef(dex_class_def)); 2192 klass->SetDexTypeIndex(dex_class_def.class_idx_); 2193 CHECK(klass->GetDexCacheStrings() != nullptr); 2194} 2195 2196void ClassLinker::LoadClass(Thread* self, const DexFile& dex_file, 2197 const DexFile::ClassDef& dex_class_def, 2198 Handle<mirror::Class> klass) { 2199 const uint8_t* class_data = dex_file.GetClassData(dex_class_def); 2200 if (class_data == nullptr) { 2201 return; // no fields or methods - for example a marker interface 2202 } 2203 bool has_oat_class = false; 2204 if (Runtime::Current()->IsStarted() && !Runtime::Current()->IsAotCompiler()) { 2205 OatFile::OatClass oat_class = FindOatClass(dex_file, klass->GetDexClassDefIndex(), 2206 &has_oat_class); 2207 if (has_oat_class) { 2208 LoadClassMembers(self, dex_file, class_data, klass, &oat_class); 2209 } 2210 } 2211 if (!has_oat_class) { 2212 LoadClassMembers(self, dex_file, class_data, klass, nullptr); 2213 } 2214} 2215 2216ArtField* ClassLinker::AllocArtFieldArray(Thread* self, size_t length) { 2217 auto* const la = Runtime::Current()->GetLinearAlloc(); 2218 auto* ptr = reinterpret_cast<ArtField*>(la->AllocArray<ArtField>(self, length)); 2219 CHECK(ptr!= nullptr); 2220 std::uninitialized_fill_n(ptr, length, ArtField()); 2221 return ptr; 2222} 2223 2224void ClassLinker::LoadClassMembers(Thread* self, const DexFile& dex_file, 2225 const uint8_t* class_data, 2226 Handle<mirror::Class> klass, 2227 const OatFile::OatClass* oat_class) { 2228 // Load static fields. 2229 ClassDataItemIterator it(dex_file, class_data); 2230 const size_t num_sfields = it.NumStaticFields(); 2231 ArtField* sfields = num_sfields != 0 ? AllocArtFieldArray(self, num_sfields) : nullptr; 2232 for (size_t i = 0; it.HasNextStaticField(); i++, it.Next()) { 2233 CHECK_LT(i, num_sfields); 2234 LoadField(it, klass, &sfields[i]); 2235 } 2236 klass->SetSFields(sfields); 2237 klass->SetNumStaticFields(num_sfields); 2238 DCHECK_EQ(klass->NumStaticFields(), num_sfields); 2239 // Load instance fields. 2240 const size_t num_ifields = it.NumInstanceFields(); 2241 ArtField* ifields = num_ifields != 0 ? AllocArtFieldArray(self, num_ifields) : nullptr; 2242 for (size_t i = 0; it.HasNextInstanceField(); i++, it.Next()) { 2243 CHECK_LT(i, num_ifields); 2244 LoadField(it, klass, &ifields[i]); 2245 } 2246 klass->SetIFields(ifields); 2247 klass->SetNumInstanceFields(num_ifields); 2248 DCHECK_EQ(klass->NumInstanceFields(), num_ifields); 2249 // Note: We cannot have thread suspension until the field arrays are setup or else 2250 // Class::VisitFieldRoots may miss some fields. 2251 self->AllowThreadSuspension(); 2252 // Load methods. 2253 if (it.NumDirectMethods() != 0) { 2254 // TODO: append direct methods to class object 2255 mirror::ObjectArray<mirror::ArtMethod>* directs = 2256 AllocArtMethodArray(self, it.NumDirectMethods()); 2257 if (UNLIKELY(directs == nullptr)) { 2258 CHECK(self->IsExceptionPending()); // OOME. 2259 return; 2260 } 2261 klass->SetDirectMethods(directs); 2262 } 2263 if (it.NumVirtualMethods() != 0) { 2264 // TODO: append direct methods to class object 2265 mirror::ObjectArray<mirror::ArtMethod>* virtuals = 2266 AllocArtMethodArray(self, it.NumVirtualMethods()); 2267 if (UNLIKELY(virtuals == nullptr)) { 2268 CHECK(self->IsExceptionPending()); // OOME. 2269 return; 2270 } 2271 klass->SetVirtualMethods(virtuals); 2272 } 2273 size_t class_def_method_index = 0; 2274 uint32_t last_dex_method_index = DexFile::kDexNoIndex; 2275 size_t last_class_def_method_index = 0; 2276 for (size_t i = 0; it.HasNextDirectMethod(); i++, it.Next()) { 2277 self->AllowThreadSuspension(); 2278 StackHandleScope<1> hs(self); 2279 Handle<mirror::ArtMethod> method(hs.NewHandle(LoadMethod(self, dex_file, it, klass))); 2280 if (UNLIKELY(method.Get() == nullptr)) { 2281 CHECK(self->IsExceptionPending()); // OOME. 2282 return; 2283 } 2284 klass->SetDirectMethod(i, method.Get()); 2285 LinkCode(method, oat_class, class_def_method_index); 2286 uint32_t it_method_index = it.GetMemberIndex(); 2287 if (last_dex_method_index == it_method_index) { 2288 // duplicate case 2289 method->SetMethodIndex(last_class_def_method_index); 2290 } else { 2291 method->SetMethodIndex(class_def_method_index); 2292 last_dex_method_index = it_method_index; 2293 last_class_def_method_index = class_def_method_index; 2294 } 2295 class_def_method_index++; 2296 } 2297 for (size_t i = 0; it.HasNextVirtualMethod(); i++, it.Next()) { 2298 self->AllowThreadSuspension(); 2299 StackHandleScope<1> hs(self); 2300 Handle<mirror::ArtMethod> method(hs.NewHandle(LoadMethod(self, dex_file, it, klass))); 2301 if (UNLIKELY(method.Get() == nullptr)) { 2302 CHECK(self->IsExceptionPending()); // OOME. 2303 return; 2304 } 2305 klass->SetVirtualMethod(i, method.Get()); 2306 DCHECK_EQ(class_def_method_index, it.NumDirectMethods() + i); 2307 LinkCode(method, oat_class, class_def_method_index); 2308 class_def_method_index++; 2309 } 2310 DCHECK(!it.HasNext()); 2311} 2312 2313void ClassLinker::LoadField(const ClassDataItemIterator& it, Handle<mirror::Class> klass, 2314 ArtField* dst) { 2315 const uint32_t field_idx = it.GetMemberIndex(); 2316 dst->SetDexFieldIndex(field_idx); 2317 dst->SetDeclaringClass(klass.Get()); 2318 dst->SetAccessFlags(it.GetFieldAccessFlags()); 2319} 2320 2321mirror::ArtMethod* ClassLinker::LoadMethod(Thread* self, const DexFile& dex_file, 2322 const ClassDataItemIterator& it, 2323 Handle<mirror::Class> klass) { 2324 uint32_t dex_method_idx = it.GetMemberIndex(); 2325 const DexFile::MethodId& method_id = dex_file.GetMethodId(dex_method_idx); 2326 const char* method_name = dex_file.StringDataByIdx(method_id.name_idx_); 2327 2328 mirror::ArtMethod* dst = AllocArtMethod(self); 2329 if (UNLIKELY(dst == nullptr)) { 2330 CHECK(self->IsExceptionPending()); // OOME. 2331 return nullptr; 2332 } 2333 DCHECK(dst->IsArtMethod()) << PrettyDescriptor(dst->GetClass()); 2334 2335 ScopedAssertNoThreadSuspension ants(self, "LoadMethod"); 2336 dst->SetDexMethodIndex(dex_method_idx); 2337 dst->SetDeclaringClass(klass.Get()); 2338 dst->SetCodeItemOffset(it.GetMethodCodeItemOffset()); 2339 2340 dst->SetDexCacheResolvedMethods(klass->GetDexCache()->GetResolvedMethods()); 2341 dst->SetDexCacheResolvedTypes(klass->GetDexCache()->GetResolvedTypes()); 2342 2343 uint32_t access_flags = it.GetMethodAccessFlags(); 2344 2345 if (UNLIKELY(strcmp("finalize", method_name) == 0)) { 2346 // Set finalizable flag on declaring class. 2347 if (strcmp("V", dex_file.GetShorty(method_id.proto_idx_)) == 0) { 2348 // Void return type. 2349 if (klass->GetClassLoader() != nullptr) { // All non-boot finalizer methods are flagged. 2350 klass->SetFinalizable(); 2351 } else { 2352 std::string temp; 2353 const char* klass_descriptor = klass->GetDescriptor(&temp); 2354 // The Enum class declares a "final" finalize() method to prevent subclasses from 2355 // introducing a finalizer. We don't want to set the finalizable flag for Enum or its 2356 // subclasses, so we exclude it here. 2357 // We also want to avoid setting the flag on Object, where we know that finalize() is 2358 // empty. 2359 if (strcmp(klass_descriptor, "Ljava/lang/Object;") != 0 && 2360 strcmp(klass_descriptor, "Ljava/lang/Enum;") != 0) { 2361 klass->SetFinalizable(); 2362 } 2363 } 2364 } 2365 } else if (method_name[0] == '<') { 2366 // Fix broken access flags for initializers. Bug 11157540. 2367 bool is_init = (strcmp("<init>", method_name) == 0); 2368 bool is_clinit = !is_init && (strcmp("<clinit>", method_name) == 0); 2369 if (UNLIKELY(!is_init && !is_clinit)) { 2370 LOG(WARNING) << "Unexpected '<' at start of method name " << method_name; 2371 } else { 2372 if (UNLIKELY((access_flags & kAccConstructor) == 0)) { 2373 LOG(WARNING) << method_name << " didn't have expected constructor access flag in class " 2374 << PrettyDescriptor(klass.Get()) << " in dex file " << dex_file.GetLocation(); 2375 access_flags |= kAccConstructor; 2376 } 2377 } 2378 } 2379 dst->SetAccessFlags(access_flags); 2380 2381 return dst; 2382} 2383 2384void ClassLinker::AppendToBootClassPath(Thread* self, const DexFile& dex_file) { 2385 StackHandleScope<1> hs(self); 2386 Handle<mirror::DexCache> dex_cache(hs.NewHandle(AllocDexCache(self, dex_file))); 2387 CHECK(dex_cache.Get() != nullptr) << "Failed to allocate dex cache for " 2388 << dex_file.GetLocation(); 2389 AppendToBootClassPath(dex_file, dex_cache); 2390} 2391 2392void ClassLinker::AppendToBootClassPath(const DexFile& dex_file, 2393 Handle<mirror::DexCache> dex_cache) { 2394 CHECK(dex_cache.Get() != nullptr) << dex_file.GetLocation(); 2395 boot_class_path_.push_back(&dex_file); 2396 RegisterDexFile(dex_file, dex_cache); 2397} 2398 2399bool ClassLinker::IsDexFileRegisteredLocked(const DexFile& dex_file) { 2400 dex_lock_.AssertSharedHeld(Thread::Current()); 2401 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2402 mirror::DexCache* dex_cache = GetDexCache(i); 2403 if (dex_cache->GetDexFile() == &dex_file) { 2404 return true; 2405 } 2406 } 2407 return false; 2408} 2409 2410bool ClassLinker::IsDexFileRegistered(const DexFile& dex_file) { 2411 ReaderMutexLock mu(Thread::Current(), dex_lock_); 2412 return IsDexFileRegisteredLocked(dex_file); 2413} 2414 2415void ClassLinker::RegisterDexFileLocked(const DexFile& dex_file, 2416 Handle<mirror::DexCache> dex_cache) { 2417 dex_lock_.AssertExclusiveHeld(Thread::Current()); 2418 CHECK(dex_cache.Get() != nullptr) << dex_file.GetLocation(); 2419 CHECK(dex_cache->GetLocation()->Equals(dex_file.GetLocation())) 2420 << dex_cache->GetLocation()->ToModifiedUtf8() << " " << dex_file.GetLocation(); 2421 dex_caches_.push_back(GcRoot<mirror::DexCache>(dex_cache.Get())); 2422 dex_cache->SetDexFile(&dex_file); 2423 if (log_new_dex_caches_roots_) { 2424 // TODO: This is not safe if we can remove dex caches. 2425 new_dex_cache_roots_.push_back(dex_caches_.size() - 1); 2426 } 2427} 2428 2429void ClassLinker::RegisterDexFile(const DexFile& dex_file) { 2430 Thread* self = Thread::Current(); 2431 { 2432 ReaderMutexLock mu(self, dex_lock_); 2433 if (IsDexFileRegisteredLocked(dex_file)) { 2434 return; 2435 } 2436 } 2437 // Don't alloc while holding the lock, since allocation may need to 2438 // suspend all threads and another thread may need the dex_lock_ to 2439 // get to a suspend point. 2440 StackHandleScope<1> hs(self); 2441 Handle<mirror::DexCache> dex_cache(hs.NewHandle(AllocDexCache(self, dex_file))); 2442 CHECK(dex_cache.Get() != nullptr) << "Failed to allocate dex cache for " 2443 << dex_file.GetLocation(); 2444 { 2445 WriterMutexLock mu(self, dex_lock_); 2446 if (IsDexFileRegisteredLocked(dex_file)) { 2447 return; 2448 } 2449 RegisterDexFileLocked(dex_file, dex_cache); 2450 } 2451} 2452 2453void ClassLinker::RegisterDexFile(const DexFile& dex_file, 2454 Handle<mirror::DexCache> dex_cache) { 2455 WriterMutexLock mu(Thread::Current(), dex_lock_); 2456 RegisterDexFileLocked(dex_file, dex_cache); 2457} 2458 2459mirror::DexCache* ClassLinker::FindDexCache(const DexFile& dex_file) { 2460 ReaderMutexLock mu(Thread::Current(), dex_lock_); 2461 // Search assuming unique-ness of dex file. 2462 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2463 mirror::DexCache* dex_cache = GetDexCache(i); 2464 if (dex_cache->GetDexFile() == &dex_file) { 2465 return dex_cache; 2466 } 2467 } 2468 // Search matching by location name. 2469 std::string location(dex_file.GetLocation()); 2470 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2471 mirror::DexCache* dex_cache = GetDexCache(i); 2472 if (dex_cache->GetDexFile()->GetLocation() == location) { 2473 return dex_cache; 2474 } 2475 } 2476 // Failure, dump diagnostic and abort. 2477 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2478 mirror::DexCache* dex_cache = GetDexCache(i); 2479 LOG(ERROR) << "Registered dex file " << i << " = " << dex_cache->GetDexFile()->GetLocation(); 2480 } 2481 LOG(FATAL) << "Failed to find DexCache for DexFile " << location; 2482 UNREACHABLE(); 2483} 2484 2485void ClassLinker::FixupDexCaches(mirror::ArtMethod* resolution_method) { 2486 ReaderMutexLock mu(Thread::Current(), dex_lock_); 2487 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2488 mirror::DexCache* dex_cache = GetDexCache(i); 2489 dex_cache->Fixup(resolution_method); 2490 } 2491} 2492 2493mirror::Class* ClassLinker::CreatePrimitiveClass(Thread* self, Primitive::Type type) { 2494 mirror::Class* klass = AllocClass(self, mirror::Class::PrimitiveClassSize()); 2495 if (UNLIKELY(klass == nullptr)) { 2496 return nullptr; 2497 } 2498 return InitializePrimitiveClass(klass, type); 2499} 2500 2501mirror::Class* ClassLinker::InitializePrimitiveClass(mirror::Class* primitive_class, 2502 Primitive::Type type) { 2503 CHECK(primitive_class != nullptr); 2504 // Must hold lock on object when initializing. 2505 Thread* self = Thread::Current(); 2506 StackHandleScope<1> hs(self); 2507 Handle<mirror::Class> h_class(hs.NewHandle(primitive_class)); 2508 ObjectLock<mirror::Class> lock(self, h_class); 2509 h_class->SetAccessFlags(kAccPublic | kAccFinal | kAccAbstract); 2510 h_class->SetPrimitiveType(type); 2511 mirror::Class::SetStatus(h_class, mirror::Class::kStatusInitialized, self); 2512 const char* descriptor = Primitive::Descriptor(type); 2513 mirror::Class* existing = InsertClass(descriptor, h_class.Get(), 2514 ComputeModifiedUtf8Hash(descriptor)); 2515 CHECK(existing == nullptr) << "InitPrimitiveClass(" << type << ") failed"; 2516 return h_class.Get(); 2517} 2518 2519// Create an array class (i.e. the class object for the array, not the 2520// array itself). "descriptor" looks like "[C" or "[[[[B" or 2521// "[Ljava/lang/String;". 2522// 2523// If "descriptor" refers to an array of primitives, look up the 2524// primitive type's internally-generated class object. 2525// 2526// "class_loader" is the class loader of the class that's referring to 2527// us. It's used to ensure that we're looking for the element type in 2528// the right context. It does NOT become the class loader for the 2529// array class; that always comes from the base element class. 2530// 2531// Returns null with an exception raised on failure. 2532mirror::Class* ClassLinker::CreateArrayClass(Thread* self, const char* descriptor, size_t hash, 2533 Handle<mirror::ClassLoader> class_loader) { 2534 // Identify the underlying component type 2535 CHECK_EQ('[', descriptor[0]); 2536 StackHandleScope<2> hs(self); 2537 MutableHandle<mirror::Class> component_type(hs.NewHandle(FindClass(self, descriptor + 1, 2538 class_loader))); 2539 if (component_type.Get() == nullptr) { 2540 DCHECK(self->IsExceptionPending()); 2541 // We need to accept erroneous classes as component types. 2542 const size_t component_hash = ComputeModifiedUtf8Hash(descriptor + 1); 2543 component_type.Assign(LookupClass(self, descriptor + 1, component_hash, class_loader.Get())); 2544 if (component_type.Get() == nullptr) { 2545 DCHECK(self->IsExceptionPending()); 2546 return nullptr; 2547 } else { 2548 self->ClearException(); 2549 } 2550 } 2551 if (UNLIKELY(component_type->IsPrimitiveVoid())) { 2552 ThrowNoClassDefFoundError("Attempt to create array of void primitive type"); 2553 return nullptr; 2554 } 2555 // See if the component type is already loaded. Array classes are 2556 // always associated with the class loader of their underlying 2557 // element type -- an array of Strings goes with the loader for 2558 // java/lang/String -- so we need to look for it there. (The 2559 // caller should have checked for the existence of the class 2560 // before calling here, but they did so with *their* class loader, 2561 // not the component type's loader.) 2562 // 2563 // If we find it, the caller adds "loader" to the class' initiating 2564 // loader list, which should prevent us from going through this again. 2565 // 2566 // This call is unnecessary if "loader" and "component_type->GetClassLoader()" 2567 // are the same, because our caller (FindClass) just did the 2568 // lookup. (Even if we get this wrong we still have correct behavior, 2569 // because we effectively do this lookup again when we add the new 2570 // class to the hash table --- necessary because of possible races with 2571 // other threads.) 2572 if (class_loader.Get() != component_type->GetClassLoader()) { 2573 mirror::Class* new_class = LookupClass(self, descriptor, hash, component_type->GetClassLoader()); 2574 if (new_class != nullptr) { 2575 return new_class; 2576 } 2577 } 2578 2579 // Fill out the fields in the Class. 2580 // 2581 // It is possible to execute some methods against arrays, because 2582 // all arrays are subclasses of java_lang_Object_, so we need to set 2583 // up a vtable. We can just point at the one in java_lang_Object_. 2584 // 2585 // Array classes are simple enough that we don't need to do a full 2586 // link step. 2587 auto new_class = hs.NewHandle<mirror::Class>(nullptr); 2588 if (UNLIKELY(!init_done_)) { 2589 // Classes that were hand created, ie not by FindSystemClass 2590 if (strcmp(descriptor, "[Ljava/lang/Class;") == 0) { 2591 new_class.Assign(GetClassRoot(kClassArrayClass)); 2592 } else if (strcmp(descriptor, "[Ljava/lang/Object;") == 0) { 2593 new_class.Assign(GetClassRoot(kObjectArrayClass)); 2594 } else if (strcmp(descriptor, GetClassRootDescriptor(kJavaLangStringArrayClass)) == 0) { 2595 new_class.Assign(GetClassRoot(kJavaLangStringArrayClass)); 2596 } else if (strcmp(descriptor, 2597 GetClassRootDescriptor(kJavaLangReflectArtMethodArrayClass)) == 0) { 2598 new_class.Assign(GetClassRoot(kJavaLangReflectArtMethodArrayClass)); 2599 } else if (strcmp(descriptor, "[C") == 0) { 2600 new_class.Assign(GetClassRoot(kCharArrayClass)); 2601 } else if (strcmp(descriptor, "[I") == 0) { 2602 new_class.Assign(GetClassRoot(kIntArrayClass)); 2603 } else if (strcmp(descriptor, "[J") == 0) { 2604 new_class.Assign(GetClassRoot(kLongArrayClass)); 2605 } 2606 } 2607 if (new_class.Get() == nullptr) { 2608 new_class.Assign(AllocClass(self, mirror::Array::ClassSize())); 2609 if (new_class.Get() == nullptr) { 2610 return nullptr; 2611 } 2612 new_class->SetComponentType(component_type.Get()); 2613 } 2614 ObjectLock<mirror::Class> lock(self, new_class); // Must hold lock on object when initializing. 2615 DCHECK(new_class->GetComponentType() != nullptr); 2616 mirror::Class* java_lang_Object = GetClassRoot(kJavaLangObject); 2617 new_class->SetSuperClass(java_lang_Object); 2618 new_class->SetVTable(java_lang_Object->GetVTable()); 2619 new_class->SetPrimitiveType(Primitive::kPrimNot); 2620 new_class->SetClassLoader(component_type->GetClassLoader()); 2621 mirror::Class::SetStatus(new_class, mirror::Class::kStatusLoaded, self); 2622 { 2623 StackHandleScope<mirror::Class::kImtSize> hs2(self, 2624 Runtime::Current()->GetImtUnimplementedMethod()); 2625 new_class->PopulateEmbeddedImtAndVTable(&hs2); 2626 } 2627 mirror::Class::SetStatus(new_class, mirror::Class::kStatusInitialized, self); 2628 // don't need to set new_class->SetObjectSize(..) 2629 // because Object::SizeOf delegates to Array::SizeOf 2630 2631 2632 // All arrays have java/lang/Cloneable and java/io/Serializable as 2633 // interfaces. We need to set that up here, so that stuff like 2634 // "instanceof" works right. 2635 // 2636 // Note: The GC could run during the call to FindSystemClass, 2637 // so we need to make sure the class object is GC-valid while we're in 2638 // there. Do this by clearing the interface list so the GC will just 2639 // think that the entries are null. 2640 2641 2642 // Use the single, global copies of "interfaces" and "iftable" 2643 // (remember not to free them for arrays). 2644 { 2645 mirror::IfTable* array_iftable = array_iftable_.Read(); 2646 CHECK(array_iftable != nullptr); 2647 new_class->SetIfTable(array_iftable); 2648 } 2649 2650 // Inherit access flags from the component type. 2651 int access_flags = new_class->GetComponentType()->GetAccessFlags(); 2652 // Lose any implementation detail flags; in particular, arrays aren't finalizable. 2653 access_flags &= kAccJavaFlagsMask; 2654 // Arrays can't be used as a superclass or interface, so we want to add "abstract final" 2655 // and remove "interface". 2656 access_flags |= kAccAbstract | kAccFinal; 2657 access_flags &= ~kAccInterface; 2658 2659 new_class->SetAccessFlags(access_flags); 2660 2661 mirror::Class* existing = InsertClass(descriptor, new_class.Get(), hash); 2662 if (existing == nullptr) { 2663 return new_class.Get(); 2664 } 2665 // Another thread must have loaded the class after we 2666 // started but before we finished. Abandon what we've 2667 // done. 2668 // 2669 // (Yes, this happens.) 2670 2671 return existing; 2672} 2673 2674mirror::Class* ClassLinker::FindPrimitiveClass(char type) { 2675 switch (type) { 2676 case 'B': 2677 return GetClassRoot(kPrimitiveByte); 2678 case 'C': 2679 return GetClassRoot(kPrimitiveChar); 2680 case 'D': 2681 return GetClassRoot(kPrimitiveDouble); 2682 case 'F': 2683 return GetClassRoot(kPrimitiveFloat); 2684 case 'I': 2685 return GetClassRoot(kPrimitiveInt); 2686 case 'J': 2687 return GetClassRoot(kPrimitiveLong); 2688 case 'S': 2689 return GetClassRoot(kPrimitiveShort); 2690 case 'Z': 2691 return GetClassRoot(kPrimitiveBoolean); 2692 case 'V': 2693 return GetClassRoot(kPrimitiveVoid); 2694 default: 2695 break; 2696 } 2697 std::string printable_type(PrintableChar(type)); 2698 ThrowNoClassDefFoundError("Not a primitive type: %s", printable_type.c_str()); 2699 return nullptr; 2700} 2701 2702mirror::Class* ClassLinker::InsertClass(const char* descriptor, mirror::Class* klass, 2703 size_t hash) { 2704 if (VLOG_IS_ON(class_linker)) { 2705 mirror::DexCache* dex_cache = klass->GetDexCache(); 2706 std::string source; 2707 if (dex_cache != nullptr) { 2708 source += " from "; 2709 source += dex_cache->GetLocation()->ToModifiedUtf8(); 2710 } 2711 LOG(INFO) << "Loaded class " << descriptor << source; 2712 } 2713 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2714 mirror::Class* existing = LookupClassFromTableLocked(descriptor, klass->GetClassLoader(), hash); 2715 if (existing != nullptr) { 2716 return existing; 2717 } 2718 if (kIsDebugBuild && !klass->IsTemp() && klass->GetClassLoader() == nullptr && 2719 dex_cache_image_class_lookup_required_) { 2720 // Check a class loaded with the system class loader matches one in the image if the class 2721 // is in the image. 2722 existing = LookupClassFromImage(descriptor); 2723 if (existing != nullptr) { 2724 CHECK_EQ(klass, existing); 2725 } 2726 } 2727 VerifyObject(klass); 2728 class_table_.InsertWithHash(GcRoot<mirror::Class>(klass), hash); 2729 if (log_new_class_table_roots_) { 2730 new_class_roots_.push_back(GcRoot<mirror::Class>(klass)); 2731 } 2732 return nullptr; 2733} 2734 2735mirror::Class* ClassLinker::UpdateClass(const char* descriptor, mirror::Class* klass, 2736 size_t hash) { 2737 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2738 auto existing_it = class_table_.FindWithHash(std::make_pair(descriptor, klass->GetClassLoader()), 2739 hash); 2740 CHECK(existing_it != class_table_.end()); 2741 mirror::Class* existing = existing_it->Read(); 2742 CHECK_NE(existing, klass) << descriptor; 2743 CHECK(!existing->IsResolved()) << descriptor; 2744 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusResolving) << descriptor; 2745 2746 CHECK(!klass->IsTemp()) << descriptor; 2747 if (kIsDebugBuild && klass->GetClassLoader() == nullptr && 2748 dex_cache_image_class_lookup_required_) { 2749 // Check a class loaded with the system class loader matches one in the image if the class 2750 // is in the image. 2751 existing = LookupClassFromImage(descriptor); 2752 if (existing != nullptr) { 2753 CHECK_EQ(klass, existing) << descriptor; 2754 } 2755 } 2756 VerifyObject(klass); 2757 2758 // Update the element in the hash set. 2759 *existing_it = GcRoot<mirror::Class>(klass); 2760 if (log_new_class_table_roots_) { 2761 new_class_roots_.push_back(GcRoot<mirror::Class>(klass)); 2762 } 2763 2764 return existing; 2765} 2766 2767bool ClassLinker::RemoveClass(const char* descriptor, mirror::ClassLoader* class_loader) { 2768 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2769 auto pair = std::make_pair(descriptor, class_loader); 2770 auto it = class_table_.Find(pair); 2771 if (it != class_table_.end()) { 2772 class_table_.Erase(it); 2773 return true; 2774 } 2775 it = pre_zygote_class_table_.Find(pair); 2776 if (it != pre_zygote_class_table_.end()) { 2777 pre_zygote_class_table_.Erase(it); 2778 return true; 2779 } 2780 return false; 2781} 2782 2783mirror::Class* ClassLinker::LookupClass(Thread* self, const char* descriptor, size_t hash, 2784 mirror::ClassLoader* class_loader) { 2785 { 2786 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 2787 mirror::Class* result = LookupClassFromTableLocked(descriptor, class_loader, hash); 2788 if (result != nullptr) { 2789 return result; 2790 } 2791 } 2792 if (class_loader != nullptr || !dex_cache_image_class_lookup_required_) { 2793 return nullptr; 2794 } else { 2795 // Lookup failed but need to search dex_caches_. 2796 mirror::Class* result = LookupClassFromImage(descriptor); 2797 if (result != nullptr) { 2798 InsertClass(descriptor, result, hash); 2799 } else { 2800 // Searching the image dex files/caches failed, we don't want to get into this situation 2801 // often as map searches are faster, so after kMaxFailedDexCacheLookups move all image 2802 // classes into the class table. 2803 constexpr uint32_t kMaxFailedDexCacheLookups = 1000; 2804 if (++failed_dex_cache_class_lookups_ > kMaxFailedDexCacheLookups) { 2805 MoveImageClassesToClassTable(); 2806 } 2807 } 2808 return result; 2809 } 2810} 2811 2812mirror::Class* ClassLinker::LookupClassFromTableLocked(const char* descriptor, 2813 mirror::ClassLoader* class_loader, 2814 size_t hash) { 2815 auto descriptor_pair = std::make_pair(descriptor, class_loader); 2816 auto it = pre_zygote_class_table_.FindWithHash(descriptor_pair, hash); 2817 if (it == pre_zygote_class_table_.end()) { 2818 it = class_table_.FindWithHash(descriptor_pair, hash); 2819 if (it == class_table_.end()) { 2820 return nullptr; 2821 } 2822 } 2823 return it->Read(); 2824} 2825 2826static mirror::ObjectArray<mirror::DexCache>* GetImageDexCaches() 2827 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 2828 gc::space::ImageSpace* image = Runtime::Current()->GetHeap()->GetImageSpace(); 2829 CHECK(image != nullptr); 2830 mirror::Object* root = image->GetImageHeader().GetImageRoot(ImageHeader::kDexCaches); 2831 return root->AsObjectArray<mirror::DexCache>(); 2832} 2833 2834void ClassLinker::MoveImageClassesToClassTable() { 2835 Thread* self = Thread::Current(); 2836 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_); 2837 if (!dex_cache_image_class_lookup_required_) { 2838 return; // All dex cache classes are already in the class table. 2839 } 2840 ScopedAssertNoThreadSuspension ants(self, "Moving image classes to class table"); 2841 mirror::ObjectArray<mirror::DexCache>* dex_caches = GetImageDexCaches(); 2842 std::string temp; 2843 for (int32_t i = 0; i < dex_caches->GetLength(); i++) { 2844 mirror::DexCache* dex_cache = dex_caches->Get(i); 2845 mirror::ObjectArray<mirror::Class>* types = dex_cache->GetResolvedTypes(); 2846 for (int32_t j = 0; j < types->GetLength(); j++) { 2847 mirror::Class* klass = types->Get(j); 2848 if (klass != nullptr) { 2849 DCHECK(klass->GetClassLoader() == nullptr); 2850 const char* descriptor = klass->GetDescriptor(&temp); 2851 size_t hash = ComputeModifiedUtf8Hash(descriptor); 2852 mirror::Class* existing = LookupClassFromTableLocked(descriptor, nullptr, hash); 2853 if (existing != nullptr) { 2854 CHECK_EQ(existing, klass) << PrettyClassAndClassLoader(existing) << " != " 2855 << PrettyClassAndClassLoader(klass); 2856 } else { 2857 class_table_.Insert(GcRoot<mirror::Class>(klass)); 2858 if (log_new_class_table_roots_) { 2859 new_class_roots_.push_back(GcRoot<mirror::Class>(klass)); 2860 } 2861 } 2862 } 2863 } 2864 } 2865 dex_cache_image_class_lookup_required_ = false; 2866} 2867 2868void ClassLinker::MoveClassTableToPreZygote() { 2869 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2870 DCHECK(pre_zygote_class_table_.Empty()); 2871 pre_zygote_class_table_ = std::move(class_table_); 2872 class_table_.Clear(); 2873} 2874 2875mirror::Class* ClassLinker::LookupClassFromImage(const char* descriptor) { 2876 ScopedAssertNoThreadSuspension ants(Thread::Current(), "Image class lookup"); 2877 mirror::ObjectArray<mirror::DexCache>* dex_caches = GetImageDexCaches(); 2878 for (int32_t i = 0; i < dex_caches->GetLength(); ++i) { 2879 mirror::DexCache* dex_cache = dex_caches->Get(i); 2880 const DexFile* dex_file = dex_cache->GetDexFile(); 2881 // Try binary searching the string/type index. 2882 const DexFile::StringId* string_id = dex_file->FindStringId(descriptor); 2883 if (string_id != nullptr) { 2884 const DexFile::TypeId* type_id = 2885 dex_file->FindTypeId(dex_file->GetIndexForStringId(*string_id)); 2886 if (type_id != nullptr) { 2887 uint16_t type_idx = dex_file->GetIndexForTypeId(*type_id); 2888 mirror::Class* klass = dex_cache->GetResolvedType(type_idx); 2889 if (klass != nullptr) { 2890 return klass; 2891 } 2892 } 2893 } 2894 } 2895 return nullptr; 2896} 2897 2898void ClassLinker::LookupClasses(const char* descriptor, std::vector<mirror::Class*>& result) { 2899 result.clear(); 2900 if (dex_cache_image_class_lookup_required_) { 2901 MoveImageClassesToClassTable(); 2902 } 2903 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2904 while (true) { 2905 auto it = class_table_.Find(descriptor); 2906 if (it == class_table_.end()) { 2907 break; 2908 } 2909 result.push_back(it->Read()); 2910 class_table_.Erase(it); 2911 } 2912 for (mirror::Class* k : result) { 2913 class_table_.Insert(GcRoot<mirror::Class>(k)); 2914 } 2915 size_t pre_zygote_start = result.size(); 2916 // Now handle the pre zygote table. 2917 // Note: This dirties the pre-zygote table but shouldn't be an issue since LookupClasses is only 2918 // called from the debugger. 2919 while (true) { 2920 auto it = pre_zygote_class_table_.Find(descriptor); 2921 if (it == pre_zygote_class_table_.end()) { 2922 break; 2923 } 2924 result.push_back(it->Read()); 2925 pre_zygote_class_table_.Erase(it); 2926 } 2927 for (size_t i = pre_zygote_start; i < result.size(); ++i) { 2928 pre_zygote_class_table_.Insert(GcRoot<mirror::Class>(result[i])); 2929 } 2930} 2931 2932void ClassLinker::VerifyClass(Thread* self, Handle<mirror::Class> klass) { 2933 // TODO: assert that the monitor on the Class is held 2934 ObjectLock<mirror::Class> lock(self, klass); 2935 2936 // Don't attempt to re-verify if already sufficiently verified. 2937 if (klass->IsVerified()) { 2938 EnsurePreverifiedMethods(klass); 2939 return; 2940 } 2941 if (klass->IsCompileTimeVerified() && Runtime::Current()->IsAotCompiler()) { 2942 return; 2943 } 2944 2945 // The class might already be erroneous, for example at compile time if we attempted to verify 2946 // this class as a parent to another. 2947 if (klass->IsErroneous()) { 2948 ThrowEarlierClassFailure(klass.Get()); 2949 return; 2950 } 2951 2952 if (klass->GetStatus() == mirror::Class::kStatusResolved) { 2953 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerifying, self); 2954 } else { 2955 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime) 2956 << PrettyClass(klass.Get()); 2957 CHECK(!Runtime::Current()->IsAotCompiler()); 2958 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerifyingAtRuntime, self); 2959 } 2960 2961 // Skip verification if disabled. 2962 if (!Runtime::Current()->IsVerificationEnabled()) { 2963 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self); 2964 EnsurePreverifiedMethods(klass); 2965 return; 2966 } 2967 2968 // Verify super class. 2969 StackHandleScope<2> hs(self); 2970 Handle<mirror::Class> super(hs.NewHandle(klass->GetSuperClass())); 2971 if (super.Get() != nullptr) { 2972 // Acquire lock to prevent races on verifying the super class. 2973 ObjectLock<mirror::Class> super_lock(self, super); 2974 2975 if (!super->IsVerified() && !super->IsErroneous()) { 2976 VerifyClass(self, super); 2977 } 2978 if (!super->IsCompileTimeVerified()) { 2979 std::string error_msg( 2980 StringPrintf("Rejecting class %s that attempts to sub-class erroneous class %s", 2981 PrettyDescriptor(klass.Get()).c_str(), 2982 PrettyDescriptor(super.Get()).c_str())); 2983 LOG(WARNING) << error_msg << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8(); 2984 Handle<mirror::Throwable> cause(hs.NewHandle(self->GetException())); 2985 if (cause.Get() != nullptr) { 2986 self->ClearException(); 2987 } 2988 ThrowVerifyError(klass.Get(), "%s", error_msg.c_str()); 2989 if (cause.Get() != nullptr) { 2990 self->GetException()->SetCause(cause.Get()); 2991 } 2992 ClassReference ref(klass->GetDexCache()->GetDexFile(), klass->GetDexClassDefIndex()); 2993 if (Runtime::Current()->IsAotCompiler()) { 2994 Runtime::Current()->GetCompilerCallbacks()->ClassRejected(ref); 2995 } 2996 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 2997 return; 2998 } 2999 } 3000 3001 // Try to use verification information from the oat file, otherwise do runtime verification. 3002 const DexFile& dex_file = *klass->GetDexCache()->GetDexFile(); 3003 mirror::Class::Status oat_file_class_status(mirror::Class::kStatusNotReady); 3004 bool preverified = VerifyClassUsingOatFile(dex_file, klass.Get(), oat_file_class_status); 3005 if (oat_file_class_status == mirror::Class::kStatusError) { 3006 VLOG(class_linker) << "Skipping runtime verification of erroneous class " 3007 << PrettyDescriptor(klass.Get()) << " in " 3008 << klass->GetDexCache()->GetLocation()->ToModifiedUtf8(); 3009 ThrowVerifyError(klass.Get(), "Rejecting class %s because it failed compile-time verification", 3010 PrettyDescriptor(klass.Get()).c_str()); 3011 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3012 return; 3013 } 3014 verifier::MethodVerifier::FailureKind verifier_failure = verifier::MethodVerifier::kNoFailure; 3015 std::string error_msg; 3016 if (!preverified) { 3017 verifier_failure = verifier::MethodVerifier::VerifyClass(self, klass.Get(), 3018 Runtime::Current()->IsAotCompiler(), 3019 &error_msg); 3020 } 3021 if (preverified || verifier_failure != verifier::MethodVerifier::kHardFailure) { 3022 if (!preverified && verifier_failure != verifier::MethodVerifier::kNoFailure) { 3023 VLOG(class_linker) << "Soft verification failure in class " << PrettyDescriptor(klass.Get()) 3024 << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8() 3025 << " because: " << error_msg; 3026 } 3027 self->AssertNoPendingException(); 3028 // Make sure all classes referenced by catch blocks are resolved. 3029 ResolveClassExceptionHandlerTypes(dex_file, klass); 3030 if (verifier_failure == verifier::MethodVerifier::kNoFailure) { 3031 // Even though there were no verifier failures we need to respect whether the super-class 3032 // was verified or requiring runtime reverification. 3033 if (super.Get() == nullptr || super->IsVerified()) { 3034 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self); 3035 } else { 3036 CHECK_EQ(super->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime); 3037 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetryVerificationAtRuntime, self); 3038 // Pretend a soft failure occured so that we don't consider the class verified below. 3039 verifier_failure = verifier::MethodVerifier::kSoftFailure; 3040 } 3041 } else { 3042 CHECK_EQ(verifier_failure, verifier::MethodVerifier::kSoftFailure); 3043 // Soft failures at compile time should be retried at runtime. Soft 3044 // failures at runtime will be handled by slow paths in the generated 3045 // code. Set status accordingly. 3046 if (Runtime::Current()->IsAotCompiler()) { 3047 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetryVerificationAtRuntime, self); 3048 } else { 3049 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self); 3050 // As this is a fake verified status, make sure the methods are _not_ marked preverified 3051 // later. 3052 klass->SetPreverified(); 3053 } 3054 } 3055 } else { 3056 LOG(WARNING) << "Verification failed on class " << PrettyDescriptor(klass.Get()) 3057 << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8() 3058 << " because: " << error_msg; 3059 self->AssertNoPendingException(); 3060 ThrowVerifyError(klass.Get(), "%s", error_msg.c_str()); 3061 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3062 } 3063 if (preverified || verifier_failure == verifier::MethodVerifier::kNoFailure) { 3064 // Class is verified so we don't need to do any access check on its methods. 3065 // Let the interpreter know it by setting the kAccPreverified flag onto each 3066 // method. 3067 // Note: we're going here during compilation and at runtime. When we set the 3068 // kAccPreverified flag when compiling image classes, the flag is recorded 3069 // in the image and is set when loading the image. 3070 EnsurePreverifiedMethods(klass); 3071 } 3072} 3073 3074void ClassLinker::EnsurePreverifiedMethods(Handle<mirror::Class> klass) { 3075 if (!klass->IsPreverified()) { 3076 klass->SetPreverifiedFlagOnAllMethods(); 3077 klass->SetPreverified(); 3078 } 3079} 3080 3081bool ClassLinker::VerifyClassUsingOatFile(const DexFile& dex_file, mirror::Class* klass, 3082 mirror::Class::Status& oat_file_class_status) { 3083 // If we're compiling, we can only verify the class using the oat file if 3084 // we are not compiling the image or if the class we're verifying is not part of 3085 // the app. In other words, we will only check for preverification of bootclasspath 3086 // classes. 3087 if (Runtime::Current()->IsAotCompiler()) { 3088 // Are we compiling the bootclasspath? 3089 if (Runtime::Current()->GetCompilerCallbacks()->IsBootImage()) { 3090 return false; 3091 } 3092 // We are compiling an app (not the image). 3093 3094 // Is this an app class? (I.e. not a bootclasspath class) 3095 if (klass->GetClassLoader() != nullptr) { 3096 return false; 3097 } 3098 } 3099 3100 const OatFile::OatDexFile* oat_dex_file = dex_file.GetOatDexFile(); 3101 // In case we run without an image there won't be a backing oat file. 3102 if (oat_dex_file == nullptr) { 3103 return false; 3104 } 3105 3106 // We may be running with a preopted oat file but without image. In this case, 3107 // we don't skip verification of preverified classes to ensure we initialize 3108 // dex caches with all types resolved during verification. 3109 // We need to trust image classes, as these might be coming out of a pre-opted, quickened boot 3110 // image (that we just failed loading), and the verifier can't be run on quickened opcodes when 3111 // the runtime isn't started. On the other hand, app classes can be re-verified even if they are 3112 // already pre-opted, as then the runtime is started. 3113 if (!Runtime::Current()->IsAotCompiler() && 3114 !Runtime::Current()->GetHeap()->HasImageSpace() && 3115 klass->GetClassLoader() != nullptr) { 3116 return false; 3117 } 3118 3119 uint16_t class_def_index = klass->GetDexClassDefIndex(); 3120 oat_file_class_status = oat_dex_file->GetOatClass(class_def_index).GetStatus(); 3121 if (oat_file_class_status == mirror::Class::kStatusVerified || 3122 oat_file_class_status == mirror::Class::kStatusInitialized) { 3123 return true; 3124 } 3125 if (oat_file_class_status == mirror::Class::kStatusRetryVerificationAtRuntime) { 3126 // Compile time verification failed with a soft error. Compile time verification can fail 3127 // because we have incomplete type information. Consider the following: 3128 // class ... { 3129 // Foo x; 3130 // .... () { 3131 // if (...) { 3132 // v1 gets assigned a type of resolved class Foo 3133 // } else { 3134 // v1 gets assigned a type of unresolved class Bar 3135 // } 3136 // iput x = v1 3137 // } } 3138 // when we merge v1 following the if-the-else it results in Conflict 3139 // (see verifier::RegType::Merge) as we can't know the type of Bar and we could possibly be 3140 // allowing an unsafe assignment to the field x in the iput (javac may have compiled this as 3141 // it knew Bar was a sub-class of Foo, but for us this may have been moved into a separate apk 3142 // at compile time). 3143 return false; 3144 } 3145 if (oat_file_class_status == mirror::Class::kStatusError) { 3146 // Compile time verification failed with a hard error. This is caused by invalid instructions 3147 // in the class. These errors are unrecoverable. 3148 return false; 3149 } 3150 if (oat_file_class_status == mirror::Class::kStatusNotReady) { 3151 // Status is uninitialized if we couldn't determine the status at compile time, for example, 3152 // not loading the class. 3153 // TODO: when the verifier doesn't rely on Class-es failing to resolve/load the type hierarchy 3154 // isn't a problem and this case shouldn't occur 3155 return false; 3156 } 3157 std::string temp; 3158 LOG(FATAL) << "Unexpected class status: " << oat_file_class_status 3159 << " " << dex_file.GetLocation() << " " << PrettyClass(klass) << " " 3160 << klass->GetDescriptor(&temp); 3161 UNREACHABLE(); 3162} 3163 3164void ClassLinker::ResolveClassExceptionHandlerTypes(const DexFile& dex_file, 3165 Handle<mirror::Class> klass) { 3166 for (size_t i = 0; i < klass->NumDirectMethods(); i++) { 3167 ResolveMethodExceptionHandlerTypes(dex_file, klass->GetDirectMethod(i)); 3168 } 3169 for (size_t i = 0; i < klass->NumVirtualMethods(); i++) { 3170 ResolveMethodExceptionHandlerTypes(dex_file, klass->GetVirtualMethod(i)); 3171 } 3172} 3173 3174void ClassLinker::ResolveMethodExceptionHandlerTypes(const DexFile& dex_file, 3175 mirror::ArtMethod* method) { 3176 // similar to DexVerifier::ScanTryCatchBlocks and dex2oat's ResolveExceptionsForMethod. 3177 const DexFile::CodeItem* code_item = dex_file.GetCodeItem(method->GetCodeItemOffset()); 3178 if (code_item == nullptr) { 3179 return; // native or abstract method 3180 } 3181 if (code_item->tries_size_ == 0) { 3182 return; // nothing to process 3183 } 3184 const uint8_t* handlers_ptr = DexFile::GetCatchHandlerData(*code_item, 0); 3185 uint32_t handlers_size = DecodeUnsignedLeb128(&handlers_ptr); 3186 ClassLinker* linker = Runtime::Current()->GetClassLinker(); 3187 for (uint32_t idx = 0; idx < handlers_size; idx++) { 3188 CatchHandlerIterator iterator(handlers_ptr); 3189 for (; iterator.HasNext(); iterator.Next()) { 3190 // Ensure exception types are resolved so that they don't need resolution to be delivered, 3191 // unresolved exception types will be ignored by exception delivery 3192 if (iterator.GetHandlerTypeIndex() != DexFile::kDexNoIndex16) { 3193 mirror::Class* exception_type = linker->ResolveType(iterator.GetHandlerTypeIndex(), method); 3194 if (exception_type == nullptr) { 3195 DCHECK(Thread::Current()->IsExceptionPending()); 3196 Thread::Current()->ClearException(); 3197 } 3198 } 3199 } 3200 handlers_ptr = iterator.EndDataPointer(); 3201 } 3202} 3203 3204static void CheckProxyConstructor(mirror::ArtMethod* constructor); 3205static void CheckProxyMethod(Handle<mirror::ArtMethod> method, 3206 Handle<mirror::ArtMethod> prototype); 3207 3208mirror::Class* ClassLinker::CreateProxyClass(ScopedObjectAccessAlreadyRunnable& soa, jstring name, 3209 jobjectArray interfaces, jobject loader, 3210 jobjectArray methods, jobjectArray throws) { 3211 Thread* self = soa.Self(); 3212 StackHandleScope<10> hs(self); 3213 MutableHandle<mirror::Class> klass(hs.NewHandle( 3214 AllocClass(self, GetClassRoot(kJavaLangClass), sizeof(mirror::Class)))); 3215 if (klass.Get() == nullptr) { 3216 CHECK(self->IsExceptionPending()); // OOME. 3217 return nullptr; 3218 } 3219 DCHECK(klass->GetClass() != nullptr); 3220 klass->SetObjectSize(sizeof(mirror::Proxy)); 3221 // Set the class access flags incl. preverified, so we do not try to set the flag on the methods. 3222 klass->SetAccessFlags(kAccClassIsProxy | kAccPublic | kAccFinal | kAccPreverified); 3223 klass->SetClassLoader(soa.Decode<mirror::ClassLoader*>(loader)); 3224 DCHECK_EQ(klass->GetPrimitiveType(), Primitive::kPrimNot); 3225 klass->SetName(soa.Decode<mirror::String*>(name)); 3226 klass->SetDexCache(GetClassRoot(kJavaLangReflectProxy)->GetDexCache()); 3227 mirror::Class::SetStatus(klass, mirror::Class::kStatusIdx, self); 3228 std::string descriptor(GetDescriptorForProxy(klass.Get())); 3229 size_t hash = ComputeModifiedUtf8Hash(descriptor.c_str()); 3230 3231 // Insert the class before loading the fields as the field roots 3232 // (ArtField::declaring_class_) are only visited from the class 3233 // table. There can't be any suspend points between inserting the 3234 // class and setting the field arrays below. 3235 mirror::Class* existing = InsertClass(descriptor.c_str(), klass.Get(), hash); 3236 CHECK(existing == nullptr); 3237 3238 // Instance fields are inherited, but we add a couple of static fields... 3239 const size_t num_fields = 2; 3240 ArtField* sfields = AllocArtFieldArray(self, num_fields); 3241 klass->SetSFields(sfields); 3242 klass->SetNumStaticFields(num_fields); 3243 3244 // 1. Create a static field 'interfaces' that holds the _declared_ interfaces implemented by 3245 // our proxy, so Class.getInterfaces doesn't return the flattened set. 3246 ArtField* interfaces_sfield = &sfields[0]; 3247 interfaces_sfield->SetDexFieldIndex(0); 3248 interfaces_sfield->SetDeclaringClass(klass.Get()); 3249 interfaces_sfield->SetAccessFlags(kAccStatic | kAccPublic | kAccFinal); 3250 3251 // 2. Create a static field 'throws' that holds exceptions thrown by our methods. 3252 ArtField* throws_sfield = &sfields[1]; 3253 throws_sfield->SetDexFieldIndex(1); 3254 throws_sfield->SetDeclaringClass(klass.Get()); 3255 throws_sfield->SetAccessFlags(kAccStatic | kAccPublic | kAccFinal); 3256 3257 // Proxies have 1 direct method, the constructor 3258 { 3259 StackHandleScope<2> hs2(self); 3260 Handle<mirror::ObjectArray<mirror::ArtMethod>> directs = 3261 hs2.NewHandle(AllocArtMethodArray(self, 1)); 3262 if (UNLIKELY(directs.Get() == nullptr)) { 3263 CHECK(self->IsExceptionPending()); // OOME. 3264 return nullptr; 3265 } 3266 klass->SetDirectMethods(directs.Get()); 3267 Handle<mirror::ArtMethod> constructor = 3268 hs2.NewHandle(CreateProxyConstructor(self, klass)); 3269 if (UNLIKELY(constructor.Get() == nullptr)) { 3270 CHECK(self->IsExceptionPending()); // OOME. 3271 return nullptr; 3272 } 3273 klass->SetDirectMethod(0, constructor.Get()); 3274 } 3275 3276 // Create virtual method using specified prototypes. 3277 auto h_methods = hs.NewHandle(soa.Decode<mirror::ObjectArray<mirror::Method>*>(methods)); 3278 DCHECK_EQ(h_methods->GetClass(), mirror::Method::ArrayClass()) 3279 << PrettyClass(h_methods->GetClass()); 3280 const size_t num_virtual_methods = h_methods->GetLength(); 3281 { 3282 StackHandleScope<1> hs2(self); 3283 Handle<mirror::ObjectArray<mirror::ArtMethod>> virtuals = 3284 hs2.NewHandle(AllocArtMethodArray(self, num_virtual_methods)); 3285 if (UNLIKELY(virtuals.Get() == nullptr)) { 3286 CHECK(self->IsExceptionPending()); // OOME. 3287 return nullptr; 3288 } 3289 klass->SetVirtualMethods(virtuals.Get()); 3290 } 3291 for (size_t i = 0; i < num_virtual_methods; ++i) { 3292 StackHandleScope<2> hs2(self); 3293 Handle<mirror::ArtMethod> prototype(hs2.NewHandle(h_methods->Get(i)->GetArtMethod())); 3294 Handle<mirror::ArtMethod> clone(hs2.NewHandle(CreateProxyMethod(self, klass, prototype))); 3295 if (UNLIKELY(clone.Get() == nullptr)) { 3296 CHECK(self->IsExceptionPending()); // OOME. 3297 return nullptr; 3298 } 3299 klass->SetVirtualMethod(i, clone.Get()); 3300 } 3301 3302 // The super class is java.lang.reflect.Proxy 3303 klass->SetSuperClass(GetClassRoot(kJavaLangReflectProxy)); 3304 // Now effectively in the loaded state. 3305 mirror::Class::SetStatus(klass, mirror::Class::kStatusLoaded, self); 3306 self->AssertNoPendingException(); 3307 3308 MutableHandle<mirror::Class> new_class = hs.NewHandle<mirror::Class>(nullptr); 3309 { 3310 // Must hold lock on object when resolved. 3311 ObjectLock<mirror::Class> resolution_lock(self, klass); 3312 // Link the fields and virtual methods, creating vtable and iftables. 3313 // The new class will replace the old one in the class table. 3314 Handle<mirror::ObjectArray<mirror::Class> > h_interfaces( 3315 hs.NewHandle(soa.Decode<mirror::ObjectArray<mirror::Class>*>(interfaces))); 3316 if (!LinkClass(self, descriptor.c_str(), klass, h_interfaces, &new_class)) { 3317 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3318 return nullptr; 3319 } 3320 } 3321 CHECK(klass->IsRetired()); 3322 CHECK_NE(klass.Get(), new_class.Get()); 3323 klass.Assign(new_class.Get()); 3324 3325 CHECK_EQ(interfaces_sfield->GetDeclaringClass(), klass.Get()); 3326 interfaces_sfield->SetObject<false>(klass.Get(), 3327 soa.Decode<mirror::ObjectArray<mirror::Class>*>(interfaces)); 3328 CHECK_EQ(throws_sfield->GetDeclaringClass(), klass.Get()); 3329 throws_sfield->SetObject<false>(klass.Get(), 3330 soa.Decode<mirror::ObjectArray<mirror::ObjectArray<mirror::Class> >*>(throws)); 3331 3332 { 3333 // Lock on klass is released. Lock new class object. 3334 ObjectLock<mirror::Class> initialization_lock(self, klass); 3335 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitialized, self); 3336 } 3337 3338 // sanity checks 3339 if (kIsDebugBuild) { 3340 CHECK(klass->GetIFields() == nullptr); 3341 CheckProxyConstructor(klass->GetDirectMethod(0)); 3342 for (size_t i = 0; i < num_virtual_methods; ++i) { 3343 StackHandleScope<2> hs2(self); 3344 Handle<mirror::ArtMethod> prototype(hs2.NewHandle(h_methods->Get(i)->GetArtMethod())); 3345 Handle<mirror::ArtMethod> virtual_method(hs2.NewHandle(klass->GetVirtualMethod(i))); 3346 CheckProxyMethod(virtual_method, prototype); 3347 } 3348 3349 StackHandleScope<1> hs2(self); 3350 Handle<mirror::String> decoded_name = hs2.NewHandle(soa.Decode<mirror::String*>(name)); 3351 std::string interfaces_field_name(StringPrintf("java.lang.Class[] %s.interfaces", 3352 decoded_name->ToModifiedUtf8().c_str())); 3353 CHECK_EQ(PrettyField(klass->GetStaticField(0)), interfaces_field_name); 3354 3355 std::string throws_field_name(StringPrintf("java.lang.Class[][] %s.throws", 3356 decoded_name->ToModifiedUtf8().c_str())); 3357 CHECK_EQ(PrettyField(klass->GetStaticField(1)), throws_field_name); 3358 3359 CHECK_EQ(klass.Get()->GetInterfaces(), 3360 soa.Decode<mirror::ObjectArray<mirror::Class>*>(interfaces)); 3361 CHECK_EQ(klass.Get()->GetThrows(), 3362 soa.Decode<mirror::ObjectArray<mirror::ObjectArray<mirror::Class>>*>(throws)); 3363 } 3364 return klass.Get(); 3365} 3366 3367std::string ClassLinker::GetDescriptorForProxy(mirror::Class* proxy_class) { 3368 DCHECK(proxy_class->IsProxyClass()); 3369 mirror::String* name = proxy_class->GetName(); 3370 DCHECK(name != nullptr); 3371 return DotToDescriptor(name->ToModifiedUtf8().c_str()); 3372} 3373 3374mirror::ArtMethod* ClassLinker::FindMethodForProxy(mirror::Class* proxy_class, 3375 mirror::ArtMethod* proxy_method) { 3376 DCHECK(proxy_class->IsProxyClass()); 3377 DCHECK(proxy_method->IsProxyMethod()); 3378 { 3379 ReaderMutexLock mu(Thread::Current(), dex_lock_); 3380 // Locate the dex cache of the original interface/Object 3381 for (const GcRoot<mirror::DexCache>& root : dex_caches_) { 3382 auto* dex_cache = root.Read(); 3383 if (proxy_method->HasSameDexCacheResolvedTypes(dex_cache->GetResolvedTypes())) { 3384 mirror::ArtMethod* resolved_method = dex_cache->GetResolvedMethod( 3385 proxy_method->GetDexMethodIndex()); 3386 CHECK(resolved_method != nullptr); 3387 return resolved_method; 3388 } 3389 } 3390 } 3391 LOG(FATAL) << "Didn't find dex cache for " << PrettyClass(proxy_class) << " " 3392 << PrettyMethod(proxy_method); 3393 UNREACHABLE(); 3394} 3395 3396 3397mirror::ArtMethod* ClassLinker::CreateProxyConstructor(Thread* self, 3398 Handle<mirror::Class> klass) { 3399 // Create constructor for Proxy that must initialize h 3400 mirror::ObjectArray<mirror::ArtMethod>* proxy_direct_methods = 3401 GetClassRoot(kJavaLangReflectProxy)->GetDirectMethods(); 3402 CHECK_EQ(proxy_direct_methods->GetLength(), 16); 3403 mirror::ArtMethod* proxy_constructor = proxy_direct_methods->Get(2); 3404 // Ensure constructor is in dex cache so that we can use the dex cache to look up the overridden 3405 // constructor method. 3406 GetClassRoot(kJavaLangReflectProxy)->GetDexCache()->SetResolvedMethod( 3407 proxy_constructor->GetDexMethodIndex(), proxy_constructor); 3408 // Clone the existing constructor of Proxy (our constructor would just invoke it so steal its 3409 // code_ too) 3410 mirror::ArtMethod* constructor = down_cast<mirror::ArtMethod*>(proxy_constructor->Clone(self)); 3411 if (constructor == nullptr) { 3412 CHECK(self->IsExceptionPending()); // OOME. 3413 return nullptr; 3414 } 3415 // Make this constructor public and fix the class to be our Proxy version 3416 constructor->SetAccessFlags((constructor->GetAccessFlags() & ~kAccProtected) | kAccPublic); 3417 constructor->SetDeclaringClass(klass.Get()); 3418 return constructor; 3419} 3420 3421static void CheckProxyConstructor(mirror::ArtMethod* constructor) 3422 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3423 CHECK(constructor->IsConstructor()); 3424 CHECK_STREQ(constructor->GetName(), "<init>"); 3425 CHECK_STREQ(constructor->GetSignature().ToString().c_str(), 3426 "(Ljava/lang/reflect/InvocationHandler;)V"); 3427 DCHECK(constructor->IsPublic()); 3428} 3429 3430mirror::ArtMethod* ClassLinker::CreateProxyMethod(Thread* self, 3431 Handle<mirror::Class> klass, 3432 Handle<mirror::ArtMethod> prototype) { 3433 // Ensure prototype is in dex cache so that we can use the dex cache to look up the overridden 3434 // prototype method 3435 auto* dex_cache = prototype->GetDeclaringClass()->GetDexCache(); 3436 // Avoid dirtying the dex cache unless we need to. 3437 if (dex_cache->GetResolvedMethod(prototype->GetDexMethodIndex()) != prototype.Get()) { 3438 dex_cache->SetResolvedMethod(prototype->GetDexMethodIndex(), prototype.Get()); 3439 } 3440 // We steal everything from the prototype (such as DexCache, invoke stub, etc.) then specialize 3441 // as necessary 3442 mirror::ArtMethod* method = down_cast<mirror::ArtMethod*>(prototype->Clone(self)); 3443 if (UNLIKELY(method == nullptr)) { 3444 CHECK(self->IsExceptionPending()); // OOME. 3445 return nullptr; 3446 } 3447 3448 // Set class to be the concrete proxy class and clear the abstract flag, modify exceptions to 3449 // the intersection of throw exceptions as defined in Proxy 3450 method->SetDeclaringClass(klass.Get()); 3451 method->SetAccessFlags((method->GetAccessFlags() & ~kAccAbstract) | kAccFinal); 3452 3453 // At runtime the method looks like a reference and argument saving method, clone the code 3454 // related parameters from this method. 3455 method->SetEntryPointFromQuickCompiledCode(GetQuickProxyInvokeHandler()); 3456 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 3457 3458 return method; 3459} 3460 3461static void CheckProxyMethod(Handle<mirror::ArtMethod> method, 3462 Handle<mirror::ArtMethod> prototype) 3463 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3464 // Basic sanity 3465 CHECK(!prototype->IsFinal()); 3466 CHECK(method->IsFinal()); 3467 CHECK(!method->IsAbstract()); 3468 3469 // The proxy method doesn't have its own dex cache or dex file and so it steals those of its 3470 // interface prototype. The exception to this are Constructors and the Class of the Proxy itself. 3471 CHECK(prototype->HasSameDexCacheResolvedMethods(method.Get())); 3472 CHECK(prototype->HasSameDexCacheResolvedTypes(method.Get())); 3473 CHECK_EQ(prototype->GetDeclaringClass()->GetDexCache(), method->GetDexCache()); 3474 CHECK_EQ(prototype->GetDexMethodIndex(), method->GetDexMethodIndex()); 3475 3476 CHECK_STREQ(method->GetName(), prototype->GetName()); 3477 CHECK_STREQ(method->GetShorty(), prototype->GetShorty()); 3478 // More complex sanity - via dex cache 3479 CHECK_EQ(method->GetInterfaceMethodIfProxy()->GetReturnType(), prototype->GetReturnType()); 3480} 3481 3482static bool CanWeInitializeClass(mirror::Class* klass, bool can_init_statics, 3483 bool can_init_parents) 3484 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3485 if (can_init_statics && can_init_parents) { 3486 return true; 3487 } 3488 if (!can_init_statics) { 3489 // Check if there's a class initializer. 3490 mirror::ArtMethod* clinit = klass->FindClassInitializer(); 3491 if (clinit != nullptr) { 3492 return false; 3493 } 3494 // Check if there are encoded static values needing initialization. 3495 if (klass->NumStaticFields() != 0) { 3496 const DexFile::ClassDef* dex_class_def = klass->GetClassDef(); 3497 DCHECK(dex_class_def != nullptr); 3498 if (dex_class_def->static_values_off_ != 0) { 3499 return false; 3500 } 3501 } 3502 } 3503 if (!klass->IsInterface() && klass->HasSuperClass()) { 3504 mirror::Class* super_class = klass->GetSuperClass(); 3505 if (!can_init_parents && !super_class->IsInitialized()) { 3506 return false; 3507 } else { 3508 if (!CanWeInitializeClass(super_class, can_init_statics, can_init_parents)) { 3509 return false; 3510 } 3511 } 3512 } 3513 return true; 3514} 3515 3516bool ClassLinker::InitializeClass(Thread* self, Handle<mirror::Class> klass, 3517 bool can_init_statics, bool can_init_parents) { 3518 // see JLS 3rd edition, 12.4.2 "Detailed Initialization Procedure" for the locking protocol 3519 3520 // Are we already initialized and therefore done? 3521 // Note: we differ from the JLS here as we don't do this under the lock, this is benign as 3522 // an initialized class will never change its state. 3523 if (klass->IsInitialized()) { 3524 return true; 3525 } 3526 3527 // Fast fail if initialization requires a full runtime. Not part of the JLS. 3528 if (!CanWeInitializeClass(klass.Get(), can_init_statics, can_init_parents)) { 3529 return false; 3530 } 3531 3532 self->AllowThreadSuspension(); 3533 uint64_t t0; 3534 { 3535 ObjectLock<mirror::Class> lock(self, klass); 3536 3537 // Re-check under the lock in case another thread initialized ahead of us. 3538 if (klass->IsInitialized()) { 3539 return true; 3540 } 3541 3542 // Was the class already found to be erroneous? Done under the lock to match the JLS. 3543 if (klass->IsErroneous()) { 3544 ThrowEarlierClassFailure(klass.Get()); 3545 VlogClassInitializationFailure(klass); 3546 return false; 3547 } 3548 3549 CHECK(klass->IsResolved()) << PrettyClass(klass.Get()) << ": state=" << klass->GetStatus(); 3550 3551 if (!klass->IsVerified()) { 3552 VerifyClass(self, klass); 3553 if (!klass->IsVerified()) { 3554 // We failed to verify, expect either the klass to be erroneous or verification failed at 3555 // compile time. 3556 if (klass->IsErroneous()) { 3557 CHECK(self->IsExceptionPending()); 3558 VlogClassInitializationFailure(klass); 3559 } else { 3560 CHECK(Runtime::Current()->IsAotCompiler()); 3561 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime); 3562 } 3563 return false; 3564 } else { 3565 self->AssertNoPendingException(); 3566 } 3567 } 3568 3569 // If the class is kStatusInitializing, either this thread is 3570 // initializing higher up the stack or another thread has beat us 3571 // to initializing and we need to wait. Either way, this 3572 // invocation of InitializeClass will not be responsible for 3573 // running <clinit> and will return. 3574 if (klass->GetStatus() == mirror::Class::kStatusInitializing) { 3575 // Could have got an exception during verification. 3576 if (self->IsExceptionPending()) { 3577 VlogClassInitializationFailure(klass); 3578 return false; 3579 } 3580 // We caught somebody else in the act; was it us? 3581 if (klass->GetClinitThreadId() == self->GetTid()) { 3582 // Yes. That's fine. Return so we can continue initializing. 3583 return true; 3584 } 3585 // No. That's fine. Wait for another thread to finish initializing. 3586 return WaitForInitializeClass(klass, self, lock); 3587 } 3588 3589 if (!ValidateSuperClassDescriptors(klass)) { 3590 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3591 return false; 3592 } 3593 self->AllowThreadSuspension(); 3594 3595 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusVerified) << PrettyClass(klass.Get()); 3596 3597 // From here out other threads may observe that we're initializing and so changes of state 3598 // require the a notification. 3599 klass->SetClinitThreadId(self->GetTid()); 3600 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitializing, self); 3601 3602 t0 = NanoTime(); 3603 } 3604 3605 // Initialize super classes, must be done while initializing for the JLS. 3606 if (!klass->IsInterface() && klass->HasSuperClass()) { 3607 mirror::Class* super_class = klass->GetSuperClass(); 3608 if (!super_class->IsInitialized()) { 3609 CHECK(!super_class->IsInterface()); 3610 CHECK(can_init_parents); 3611 StackHandleScope<1> hs(self); 3612 Handle<mirror::Class> handle_scope_super(hs.NewHandle(super_class)); 3613 bool super_initialized = InitializeClass(self, handle_scope_super, can_init_statics, true); 3614 if (!super_initialized) { 3615 // The super class was verified ahead of entering initializing, we should only be here if 3616 // the super class became erroneous due to initialization. 3617 CHECK(handle_scope_super->IsErroneous() && self->IsExceptionPending()) 3618 << "Super class initialization failed for " 3619 << PrettyDescriptor(handle_scope_super.Get()) 3620 << " that has unexpected status " << handle_scope_super->GetStatus() 3621 << "\nPending exception:\n" 3622 << (self->GetException() != nullptr ? self->GetException()->Dump() : ""); 3623 ObjectLock<mirror::Class> lock(self, klass); 3624 // Initialization failed because the super-class is erroneous. 3625 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3626 return false; 3627 } 3628 } 3629 } 3630 3631 const size_t num_static_fields = klass->NumStaticFields(); 3632 if (num_static_fields > 0) { 3633 const DexFile::ClassDef* dex_class_def = klass->GetClassDef(); 3634 CHECK(dex_class_def != nullptr); 3635 const DexFile& dex_file = klass->GetDexFile(); 3636 StackHandleScope<3> hs(self); 3637 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(klass->GetClassLoader())); 3638 Handle<mirror::DexCache> dex_cache(hs.NewHandle(klass->GetDexCache())); 3639 3640 // Eagerly fill in static fields so that the we don't have to do as many expensive 3641 // Class::FindStaticField in ResolveField. 3642 for (size_t i = 0; i < num_static_fields; ++i) { 3643 ArtField* field = klass->GetStaticField(i); 3644 const uint32_t field_idx = field->GetDexFieldIndex(); 3645 ArtField* resolved_field = dex_cache->GetResolvedField(field_idx, image_pointer_size_); 3646 if (resolved_field == nullptr) { 3647 dex_cache->SetResolvedField(field_idx, field, image_pointer_size_); 3648 } else { 3649 DCHECK_EQ(field, resolved_field); 3650 } 3651 } 3652 3653 EncodedStaticFieldValueIterator value_it(dex_file, &dex_cache, &class_loader, 3654 this, *dex_class_def); 3655 const uint8_t* class_data = dex_file.GetClassData(*dex_class_def); 3656 ClassDataItemIterator field_it(dex_file, class_data); 3657 if (value_it.HasNext()) { 3658 DCHECK(field_it.HasNextStaticField()); 3659 CHECK(can_init_statics); 3660 for ( ; value_it.HasNext(); value_it.Next(), field_it.Next()) { 3661 ArtField* field = ResolveField( 3662 dex_file, field_it.GetMemberIndex(), dex_cache, class_loader, true); 3663 if (Runtime::Current()->IsActiveTransaction()) { 3664 value_it.ReadValueToField<true>(field); 3665 } else { 3666 value_it.ReadValueToField<false>(field); 3667 } 3668 DCHECK(!value_it.HasNext() || field_it.HasNextStaticField()); 3669 } 3670 } 3671 } 3672 3673 mirror::ArtMethod* clinit = klass->FindClassInitializer(); 3674 if (clinit != nullptr) { 3675 CHECK(can_init_statics); 3676 JValue result; 3677 clinit->Invoke(self, nullptr, 0, &result, "V"); 3678 } 3679 3680 self->AllowThreadSuspension(); 3681 uint64_t t1 = NanoTime(); 3682 3683 bool success = true; 3684 { 3685 ObjectLock<mirror::Class> lock(self, klass); 3686 3687 if (self->IsExceptionPending()) { 3688 WrapExceptionInInitializer(klass); 3689 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3690 success = false; 3691 } else if (Runtime::Current()->IsTransactionAborted()) { 3692 // The exception thrown when the transaction aborted has been caught and cleared 3693 // so we need to throw it again now. 3694 VLOG(compiler) << "Return from class initializer of " << PrettyDescriptor(klass.Get()) 3695 << " without exception while transaction was aborted: re-throw it now."; 3696 Runtime::Current()->ThrowTransactionAbortError(self); 3697 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3698 success = false; 3699 } else { 3700 RuntimeStats* global_stats = Runtime::Current()->GetStats(); 3701 RuntimeStats* thread_stats = self->GetStats(); 3702 ++global_stats->class_init_count; 3703 ++thread_stats->class_init_count; 3704 global_stats->class_init_time_ns += (t1 - t0); 3705 thread_stats->class_init_time_ns += (t1 - t0); 3706 // Set the class as initialized except if failed to initialize static fields. 3707 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitialized, self); 3708 if (VLOG_IS_ON(class_linker)) { 3709 std::string temp; 3710 LOG(INFO) << "Initialized class " << klass->GetDescriptor(&temp) << " from " << 3711 klass->GetLocation(); 3712 } 3713 // Opportunistically set static method trampolines to their destination. 3714 FixupStaticTrampolines(klass.Get()); 3715 } 3716 } 3717 return success; 3718} 3719 3720bool ClassLinker::WaitForInitializeClass(Handle<mirror::Class> klass, Thread* self, 3721 ObjectLock<mirror::Class>& lock) 3722 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3723 while (true) { 3724 self->AssertNoPendingException(); 3725 CHECK(!klass->IsInitialized()); 3726 lock.WaitIgnoringInterrupts(); 3727 3728 // When we wake up, repeat the test for init-in-progress. If 3729 // there's an exception pending (only possible if 3730 // we were not using WaitIgnoringInterrupts), bail out. 3731 if (self->IsExceptionPending()) { 3732 WrapExceptionInInitializer(klass); 3733 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3734 return false; 3735 } 3736 // Spurious wakeup? Go back to waiting. 3737 if (klass->GetStatus() == mirror::Class::kStatusInitializing) { 3738 continue; 3739 } 3740 if (klass->GetStatus() == mirror::Class::kStatusVerified && 3741 Runtime::Current()->IsAotCompiler()) { 3742 // Compile time initialization failed. 3743 return false; 3744 } 3745 if (klass->IsErroneous()) { 3746 // The caller wants an exception, but it was thrown in a 3747 // different thread. Synthesize one here. 3748 ThrowNoClassDefFoundError("<clinit> failed for class %s; see exception in other thread", 3749 PrettyDescriptor(klass.Get()).c_str()); 3750 VlogClassInitializationFailure(klass); 3751 return false; 3752 } 3753 if (klass->IsInitialized()) { 3754 return true; 3755 } 3756 LOG(FATAL) << "Unexpected class status. " << PrettyClass(klass.Get()) << " is " 3757 << klass->GetStatus(); 3758 } 3759 UNREACHABLE(); 3760} 3761 3762static bool HasSameSignatureWithDifferentClassLoaders(Thread* self, 3763 Handle<mirror::ArtMethod> method1, 3764 Handle<mirror::ArtMethod> method2, 3765 std::string* error_msg) 3766 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3767 { 3768 StackHandleScope<1> hs(self); 3769 Handle<mirror::Class> return_type(hs.NewHandle(method1->GetReturnType())); 3770 mirror::Class* other_return_type = method2->GetReturnType(); 3771 // NOTE: return_type.Get() must be sequenced after method2->GetReturnType(). 3772 if (UNLIKELY(other_return_type != return_type.Get())) { 3773 *error_msg = StringPrintf("Return types mismatch: %s(%p) vs %s(%p)", 3774 PrettyClassAndClassLoader(return_type.Get()).c_str(), 3775 return_type.Get(), 3776 PrettyClassAndClassLoader(other_return_type).c_str(), 3777 other_return_type); 3778 return false; 3779 } 3780 } 3781 const DexFile::TypeList* types1 = method1->GetParameterTypeList(); 3782 const DexFile::TypeList* types2 = method2->GetParameterTypeList(); 3783 if (types1 == nullptr) { 3784 if (types2 != nullptr && types2->Size() != 0) { 3785 *error_msg = StringPrintf("Type list mismatch with %s", 3786 PrettyMethod(method2.Get(), true).c_str()); 3787 return false; 3788 } 3789 return true; 3790 } else if (UNLIKELY(types2 == nullptr)) { 3791 if (types1->Size() != 0) { 3792 *error_msg = StringPrintf("Type list mismatch with %s", 3793 PrettyMethod(method2.Get(), true).c_str()); 3794 return false; 3795 } 3796 return true; 3797 } 3798 uint32_t num_types = types1->Size(); 3799 if (UNLIKELY(num_types != types2->Size())) { 3800 *error_msg = StringPrintf("Type list mismatch with %s", 3801 PrettyMethod(method2.Get(), true).c_str()); 3802 return false; 3803 } 3804 for (uint32_t i = 0; i < num_types; ++i) { 3805 StackHandleScope<1> hs(self); 3806 Handle<mirror::Class> param_type(hs.NewHandle( 3807 method1->GetClassFromTypeIndex(types1->GetTypeItem(i).type_idx_, true))); 3808 mirror::Class* other_param_type = 3809 method2->GetClassFromTypeIndex(types2->GetTypeItem(i).type_idx_, true); 3810 // NOTE: param_type.Get() must be sequenced after method2->GetClassFromTypeIndex(...). 3811 if (UNLIKELY(param_type.Get() != other_param_type)) { 3812 *error_msg = StringPrintf("Parameter %u type mismatch: %s(%p) vs %s(%p)", 3813 i, 3814 PrettyClassAndClassLoader(param_type.Get()).c_str(), 3815 param_type.Get(), 3816 PrettyClassAndClassLoader(other_param_type).c_str(), 3817 other_param_type); 3818 return false; 3819 } 3820 } 3821 return true; 3822} 3823 3824 3825bool ClassLinker::ValidateSuperClassDescriptors(Handle<mirror::Class> klass) { 3826 if (klass->IsInterface()) { 3827 return true; 3828 } 3829 // Begin with the methods local to the superclass. 3830 Thread* self = Thread::Current(); 3831 StackHandleScope<2> hs(self); 3832 MutableHandle<mirror::ArtMethod> h_m(hs.NewHandle<mirror::ArtMethod>(nullptr)); 3833 MutableHandle<mirror::ArtMethod> super_h_m(hs.NewHandle<mirror::ArtMethod>(nullptr)); 3834 if (klass->HasSuperClass() && 3835 klass->GetClassLoader() != klass->GetSuperClass()->GetClassLoader()) { 3836 for (int i = klass->GetSuperClass()->GetVTableLength() - 1; i >= 0; --i) { 3837 h_m.Assign(klass->GetVTableEntry(i)); 3838 super_h_m.Assign(klass->GetSuperClass()->GetVTableEntry(i)); 3839 if (h_m.Get() != super_h_m.Get()) { 3840 std::string error_msg; 3841 if (!HasSameSignatureWithDifferentClassLoaders(self, h_m, super_h_m, &error_msg)) { 3842 ThrowLinkageError(klass.Get(), 3843 "Class %s method %s resolves differently in superclass %s: %s", 3844 PrettyDescriptor(klass.Get()).c_str(), 3845 PrettyMethod(h_m.Get()).c_str(), 3846 PrettyDescriptor(klass->GetSuperClass()).c_str(), 3847 error_msg.c_str()); 3848 return false; 3849 } 3850 } 3851 } 3852 } 3853 for (int32_t i = 0; i < klass->GetIfTableCount(); ++i) { 3854 if (klass->GetClassLoader() != klass->GetIfTable()->GetInterface(i)->GetClassLoader()) { 3855 uint32_t num_methods = klass->GetIfTable()->GetInterface(i)->NumVirtualMethods(); 3856 for (uint32_t j = 0; j < num_methods; ++j) { 3857 h_m.Assign(klass->GetIfTable()->GetMethodArray(i)->GetWithoutChecks(j)); 3858 super_h_m.Assign(klass->GetIfTable()->GetInterface(i)->GetVirtualMethod(j)); 3859 if (h_m.Get() != super_h_m.Get()) { 3860 std::string error_msg; 3861 if (!HasSameSignatureWithDifferentClassLoaders(self, h_m, super_h_m, &error_msg)) { 3862 ThrowLinkageError(klass.Get(), 3863 "Class %s method %s resolves differently in interface %s: %s", 3864 PrettyDescriptor(klass.Get()).c_str(), 3865 PrettyMethod(h_m.Get()).c_str(), 3866 PrettyDescriptor(klass->GetIfTable()->GetInterface(i)).c_str(), 3867 error_msg.c_str()); 3868 return false; 3869 } 3870 } 3871 } 3872 } 3873 } 3874 return true; 3875} 3876 3877bool ClassLinker::EnsureInitialized(Thread* self, Handle<mirror::Class> c, bool can_init_fields, 3878 bool can_init_parents) { 3879 DCHECK(c.Get() != nullptr); 3880 if (c->IsInitialized()) { 3881 EnsurePreverifiedMethods(c); 3882 return true; 3883 } 3884 const bool success = InitializeClass(self, c, can_init_fields, can_init_parents); 3885 if (!success) { 3886 if (can_init_fields && can_init_parents) { 3887 CHECK(self->IsExceptionPending()) << PrettyClass(c.Get()); 3888 } 3889 } else { 3890 self->AssertNoPendingException(); 3891 } 3892 return success; 3893} 3894 3895void ClassLinker::FixupTemporaryDeclaringClass(mirror::Class* temp_class, mirror::Class* new_class) { 3896 ArtField* fields = new_class->GetIFields(); 3897 for (size_t i = 0, count = new_class->NumInstanceFields(); i < count; i++) { 3898 if (fields[i].GetDeclaringClass() == temp_class) { 3899 fields[i].SetDeclaringClass(new_class); 3900 } 3901 } 3902 3903 fields = new_class->GetSFields(); 3904 for (size_t i = 0, count = new_class->NumStaticFields(); i < count; i++) { 3905 if (fields[i].GetDeclaringClass() == temp_class) { 3906 fields[i].SetDeclaringClass(new_class); 3907 } 3908 } 3909 3910 mirror::ObjectArray<mirror::ArtMethod>* methods = new_class->GetDirectMethods(); 3911 if (methods != nullptr) { 3912 for (int index = 0; index < methods->GetLength(); index ++) { 3913 if (methods->Get(index)->GetDeclaringClass() == temp_class) { 3914 methods->Get(index)->SetDeclaringClass(new_class); 3915 } 3916 } 3917 } 3918 3919 methods = new_class->GetVirtualMethods(); 3920 if (methods != nullptr) { 3921 for (int index = 0; index < methods->GetLength(); index ++) { 3922 if (methods->Get(index)->GetDeclaringClass() == temp_class) { 3923 methods->Get(index)->SetDeclaringClass(new_class); 3924 } 3925 } 3926 } 3927} 3928 3929bool ClassLinker::LinkClass(Thread* self, const char* descriptor, Handle<mirror::Class> klass, 3930 Handle<mirror::ObjectArray<mirror::Class>> interfaces, 3931 MutableHandle<mirror::Class>* h_new_class_out) { 3932 CHECK_EQ(mirror::Class::kStatusLoaded, klass->GetStatus()); 3933 3934 if (!LinkSuperClass(klass)) { 3935 return false; 3936 } 3937 StackHandleScope<mirror::Class::kImtSize> imt_handle_scope( 3938 self, Runtime::Current()->GetImtUnimplementedMethod()); 3939 if (!LinkMethods(self, klass, interfaces, &imt_handle_scope)) { 3940 return false; 3941 } 3942 if (!LinkInstanceFields(self, klass)) { 3943 return false; 3944 } 3945 size_t class_size; 3946 if (!LinkStaticFields(self, klass, &class_size)) { 3947 return false; 3948 } 3949 CreateReferenceInstanceOffsets(klass); 3950 CHECK_EQ(mirror::Class::kStatusLoaded, klass->GetStatus()); 3951 3952 if (!klass->IsTemp() || (!init_done_ && klass->GetClassSize() == class_size)) { 3953 // We don't need to retire this class as it has no embedded tables or it was created the 3954 // correct size during class linker initialization. 3955 CHECK_EQ(klass->GetClassSize(), class_size) << PrettyDescriptor(klass.Get()); 3956 3957 if (klass->ShouldHaveEmbeddedImtAndVTable()) { 3958 klass->PopulateEmbeddedImtAndVTable(&imt_handle_scope); 3959 } 3960 3961 // This will notify waiters on klass that saw the not yet resolved 3962 // class in the class_table_ during EnsureResolved. 3963 mirror::Class::SetStatus(klass, mirror::Class::kStatusResolved, self); 3964 h_new_class_out->Assign(klass.Get()); 3965 } else { 3966 CHECK(!klass->IsResolved()); 3967 // Retire the temporary class and create the correctly sized resolved class. 3968 StackHandleScope<1> hs(self); 3969 auto h_new_class = hs.NewHandle<mirror::Class>( 3970 klass->CopyOf(self, class_size, &imt_handle_scope)); 3971 if (UNLIKELY(h_new_class.Get() == 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(h_new_class->GetClassSize(), class_size); 3978 ObjectLock<mirror::Class> lock(self, h_new_class); 3979 FixupTemporaryDeclaringClass(klass.Get(), h_new_class.Get()); 3980 mirror::Class* existing = UpdateClass(descriptor, h_new_class.Get(), 3981 ComputeModifiedUtf8Hash(descriptor)); 3982 CHECK(existing == nullptr || existing == klass.Get()); 3983 3984 // This will notify waiters on temp class that saw the not yet resolved class in the 3985 // class_table_ during EnsureResolved. 3986 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetired, self); 3987 3988 CHECK_EQ(h_new_class->GetStatus(), mirror::Class::kStatusResolving); 3989 // This will notify waiters on new_class that saw the not yet resolved 3990 // class in the class_table_ during EnsureResolved. 3991 mirror::Class::SetStatus(h_new_class, mirror::Class::kStatusResolved, self); 3992 // Return the new class. 3993 h_new_class_out->Assign(h_new_class.Get()); 3994 } 3995 return true; 3996} 3997 3998static void CountMethodsAndFields(ClassDataItemIterator& dex_data, 3999 size_t* virtual_methods, 4000 size_t* direct_methods, 4001 size_t* static_fields, 4002 size_t* instance_fields) { 4003 *virtual_methods = *direct_methods = *static_fields = *instance_fields = 0; 4004 4005 while (dex_data.HasNextStaticField()) { 4006 dex_data.Next(); 4007 (*static_fields)++; 4008 } 4009 while (dex_data.HasNextInstanceField()) { 4010 dex_data.Next(); 4011 (*instance_fields)++; 4012 } 4013 while (dex_data.HasNextDirectMethod()) { 4014 (*direct_methods)++; 4015 dex_data.Next(); 4016 } 4017 while (dex_data.HasNextVirtualMethod()) { 4018 (*virtual_methods)++; 4019 dex_data.Next(); 4020 } 4021 DCHECK(!dex_data.HasNext()); 4022} 4023 4024static void DumpClass(std::ostream& os, 4025 const DexFile& dex_file, const DexFile::ClassDef& dex_class_def, 4026 const char* suffix) { 4027 ClassDataItemIterator dex_data(dex_file, dex_file.GetClassData(dex_class_def)); 4028 os << dex_file.GetClassDescriptor(dex_class_def) << suffix << ":\n"; 4029 os << " Static fields:\n"; 4030 while (dex_data.HasNextStaticField()) { 4031 const DexFile::FieldId& id = dex_file.GetFieldId(dex_data.GetMemberIndex()); 4032 os << " " << dex_file.GetFieldTypeDescriptor(id) << " " << dex_file.GetFieldName(id) << "\n"; 4033 dex_data.Next(); 4034 } 4035 os << " Instance fields:\n"; 4036 while (dex_data.HasNextInstanceField()) { 4037 const DexFile::FieldId& id = dex_file.GetFieldId(dex_data.GetMemberIndex()); 4038 os << " " << dex_file.GetFieldTypeDescriptor(id) << " " << dex_file.GetFieldName(id) << "\n"; 4039 dex_data.Next(); 4040 } 4041 os << " Direct methods:\n"; 4042 while (dex_data.HasNextDirectMethod()) { 4043 const DexFile::MethodId& id = dex_file.GetMethodId(dex_data.GetMemberIndex()); 4044 os << " " << dex_file.GetMethodName(id) << dex_file.GetMethodSignature(id).ToString() << "\n"; 4045 dex_data.Next(); 4046 } 4047 os << " Virtual methods:\n"; 4048 while (dex_data.HasNextVirtualMethod()) { 4049 const DexFile::MethodId& id = dex_file.GetMethodId(dex_data.GetMemberIndex()); 4050 os << " " << dex_file.GetMethodName(id) << dex_file.GetMethodSignature(id).ToString() << "\n"; 4051 dex_data.Next(); 4052 } 4053} 4054 4055static std::string DumpClasses(const DexFile& dex_file1, const DexFile::ClassDef& dex_class_def1, 4056 const DexFile& dex_file2, const DexFile::ClassDef& dex_class_def2) { 4057 std::ostringstream os; 4058 DumpClass(os, dex_file1, dex_class_def1, " (Compile time)"); 4059 DumpClass(os, dex_file2, dex_class_def2, " (Runtime)"); 4060 return os.str(); 4061} 4062 4063 4064// Very simple structural check on whether the classes match. Only compares the number of 4065// methods and fields. 4066static bool SimpleStructuralCheck(const DexFile& dex_file1, const DexFile::ClassDef& dex_class_def1, 4067 const DexFile& dex_file2, const DexFile::ClassDef& dex_class_def2, 4068 std::string* error_msg) { 4069 ClassDataItemIterator dex_data1(dex_file1, dex_file1.GetClassData(dex_class_def1)); 4070 ClassDataItemIterator dex_data2(dex_file2, dex_file2.GetClassData(dex_class_def2)); 4071 4072 // Counters for current dex file. 4073 size_t dex_virtual_methods1, dex_direct_methods1, dex_static_fields1, dex_instance_fields1; 4074 CountMethodsAndFields(dex_data1, &dex_virtual_methods1, &dex_direct_methods1, &dex_static_fields1, 4075 &dex_instance_fields1); 4076 // Counters for compile-time dex file. 4077 size_t dex_virtual_methods2, dex_direct_methods2, dex_static_fields2, dex_instance_fields2; 4078 CountMethodsAndFields(dex_data2, &dex_virtual_methods2, &dex_direct_methods2, &dex_static_fields2, 4079 &dex_instance_fields2); 4080 4081 if (dex_virtual_methods1 != dex_virtual_methods2) { 4082 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 4083 *error_msg = StringPrintf("Virtual method count off: %zu vs %zu\n%s", dex_virtual_methods1, 4084 dex_virtual_methods2, class_dump.c_str()); 4085 return false; 4086 } 4087 if (dex_direct_methods1 != dex_direct_methods2) { 4088 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 4089 *error_msg = StringPrintf("Direct method count off: %zu vs %zu\n%s", dex_direct_methods1, 4090 dex_direct_methods2, class_dump.c_str()); 4091 return false; 4092 } 4093 if (dex_static_fields1 != dex_static_fields2) { 4094 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 4095 *error_msg = StringPrintf("Static field count off: %zu vs %zu\n%s", dex_static_fields1, 4096 dex_static_fields2, class_dump.c_str()); 4097 return false; 4098 } 4099 if (dex_instance_fields1 != dex_instance_fields2) { 4100 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 4101 *error_msg = StringPrintf("Instance field count off: %zu vs %zu\n%s", dex_instance_fields1, 4102 dex_instance_fields2, class_dump.c_str()); 4103 return false; 4104 } 4105 4106 return true; 4107} 4108 4109// Checks whether a the super-class changed from what we had at compile-time. This would 4110// invalidate quickening. 4111static bool CheckSuperClassChange(Handle<mirror::Class> klass, 4112 const DexFile& dex_file, 4113 const DexFile::ClassDef& class_def, 4114 mirror::Class* super_class) 4115 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4116 // Check for unexpected changes in the superclass. 4117 // Quick check 1) is the super_class class-loader the boot class loader? This always has 4118 // precedence. 4119 if (super_class->GetClassLoader() != nullptr && 4120 // Quick check 2) different dex cache? Breaks can only occur for different dex files, 4121 // which is implied by different dex cache. 4122 klass->GetDexCache() != super_class->GetDexCache()) { 4123 // Now comes the expensive part: things can be broken if (a) the klass' dex file has a 4124 // definition for the super-class, and (b) the files are in separate oat files. The oat files 4125 // are referenced from the dex file, so do (b) first. Only relevant if we have oat files. 4126 const OatDexFile* class_oat_dex_file = dex_file.GetOatDexFile(); 4127 const OatFile* class_oat_file = nullptr; 4128 if (class_oat_dex_file != nullptr) { 4129 class_oat_file = class_oat_dex_file->GetOatFile(); 4130 } 4131 4132 if (class_oat_file != nullptr) { 4133 const OatDexFile* loaded_super_oat_dex_file = super_class->GetDexFile().GetOatDexFile(); 4134 const OatFile* loaded_super_oat_file = nullptr; 4135 if (loaded_super_oat_dex_file != nullptr) { 4136 loaded_super_oat_file = loaded_super_oat_dex_file->GetOatFile(); 4137 } 4138 4139 if (loaded_super_oat_file != nullptr && class_oat_file != loaded_super_oat_file) { 4140 // Now check (a). 4141 const DexFile::ClassDef* super_class_def = dex_file.FindClassDef(class_def.superclass_idx_); 4142 if (super_class_def != nullptr) { 4143 // Uh-oh, we found something. Do our check. 4144 std::string error_msg; 4145 if (!SimpleStructuralCheck(dex_file, *super_class_def, 4146 super_class->GetDexFile(), *super_class->GetClassDef(), 4147 &error_msg)) { 4148 // Print a warning to the log. This exception might be caught, e.g., as common in test 4149 // drivers. When the class is later tried to be used, we re-throw a new instance, as we 4150 // only save the type of the exception. 4151 LOG(WARNING) << "Incompatible structural change detected: " << 4152 StringPrintf( 4153 "Structural change of %s is hazardous (%s at compile time, %s at runtime): %s", 4154 PrettyType(super_class_def->class_idx_, dex_file).c_str(), 4155 class_oat_file->GetLocation().c_str(), 4156 loaded_super_oat_file->GetLocation().c_str(), 4157 error_msg.c_str()); 4158 ThrowIncompatibleClassChangeError(klass.Get(), 4159 "Structural change of %s is hazardous (%s at compile time, %s at runtime): %s", 4160 PrettyType(super_class_def->class_idx_, dex_file).c_str(), 4161 class_oat_file->GetLocation().c_str(), 4162 loaded_super_oat_file->GetLocation().c_str(), 4163 error_msg.c_str()); 4164 return false; 4165 } 4166 } 4167 } 4168 } 4169 } 4170 return true; 4171} 4172 4173bool ClassLinker::LoadSuperAndInterfaces(Handle<mirror::Class> klass, const DexFile& dex_file) { 4174 CHECK_EQ(mirror::Class::kStatusIdx, klass->GetStatus()); 4175 const DexFile::ClassDef& class_def = dex_file.GetClassDef(klass->GetDexClassDefIndex()); 4176 uint16_t super_class_idx = class_def.superclass_idx_; 4177 if (super_class_idx != DexFile::kDexNoIndex16) { 4178 mirror::Class* super_class = ResolveType(dex_file, super_class_idx, klass.Get()); 4179 if (super_class == nullptr) { 4180 DCHECK(Thread::Current()->IsExceptionPending()); 4181 return false; 4182 } 4183 // Verify 4184 if (!klass->CanAccess(super_class)) { 4185 ThrowIllegalAccessError(klass.Get(), "Class %s extended by class %s is inaccessible", 4186 PrettyDescriptor(super_class).c_str(), 4187 PrettyDescriptor(klass.Get()).c_str()); 4188 return false; 4189 } 4190 CHECK(super_class->IsResolved()); 4191 klass->SetSuperClass(super_class); 4192 4193 if (!CheckSuperClassChange(klass, dex_file, class_def, super_class)) { 4194 DCHECK(Thread::Current()->IsExceptionPending()); 4195 return false; 4196 } 4197 } 4198 const DexFile::TypeList* interfaces = dex_file.GetInterfacesList(class_def); 4199 if (interfaces != nullptr) { 4200 for (size_t i = 0; i < interfaces->Size(); i++) { 4201 uint16_t idx = interfaces->GetTypeItem(i).type_idx_; 4202 mirror::Class* interface = ResolveType(dex_file, idx, klass.Get()); 4203 if (interface == nullptr) { 4204 DCHECK(Thread::Current()->IsExceptionPending()); 4205 return false; 4206 } 4207 // Verify 4208 if (!klass->CanAccess(interface)) { 4209 // TODO: the RI seemed to ignore this in my testing. 4210 ThrowIllegalAccessError(klass.Get(), "Interface %s implemented by class %s is inaccessible", 4211 PrettyDescriptor(interface).c_str(), 4212 PrettyDescriptor(klass.Get()).c_str()); 4213 return false; 4214 } 4215 } 4216 } 4217 // Mark the class as loaded. 4218 mirror::Class::SetStatus(klass, mirror::Class::kStatusLoaded, nullptr); 4219 return true; 4220} 4221 4222bool ClassLinker::LinkSuperClass(Handle<mirror::Class> klass) { 4223 CHECK(!klass->IsPrimitive()); 4224 mirror::Class* super = klass->GetSuperClass(); 4225 if (klass.Get() == GetClassRoot(kJavaLangObject)) { 4226 if (super != nullptr) { 4227 ThrowClassFormatError(klass.Get(), "java.lang.Object must not have a superclass"); 4228 return false; 4229 } 4230 return true; 4231 } 4232 if (super == nullptr) { 4233 ThrowLinkageError(klass.Get(), "No superclass defined for class %s", 4234 PrettyDescriptor(klass.Get()).c_str()); 4235 return false; 4236 } 4237 // Verify 4238 if (super->IsFinal() || super->IsInterface()) { 4239 ThrowIncompatibleClassChangeError(klass.Get(), "Superclass %s of %s is %s", 4240 PrettyDescriptor(super).c_str(), 4241 PrettyDescriptor(klass.Get()).c_str(), 4242 super->IsFinal() ? "declared final" : "an interface"); 4243 return false; 4244 } 4245 if (!klass->CanAccess(super)) { 4246 ThrowIllegalAccessError(klass.Get(), "Superclass %s is inaccessible to class %s", 4247 PrettyDescriptor(super).c_str(), 4248 PrettyDescriptor(klass.Get()).c_str()); 4249 return false; 4250 } 4251 4252 // Inherit kAccClassIsFinalizable from the superclass in case this 4253 // class doesn't override finalize. 4254 if (super->IsFinalizable()) { 4255 klass->SetFinalizable(); 4256 } 4257 4258 // Inherit reference flags (if any) from the superclass. 4259 int reference_flags = (super->GetAccessFlags() & kAccReferenceFlagsMask); 4260 if (reference_flags != 0) { 4261 klass->SetAccessFlags(klass->GetAccessFlags() | reference_flags); 4262 } 4263 // Disallow custom direct subclasses of java.lang.ref.Reference. 4264 if (init_done_ && super == GetClassRoot(kJavaLangRefReference)) { 4265 ThrowLinkageError(klass.Get(), 4266 "Class %s attempts to subclass java.lang.ref.Reference, which is not allowed", 4267 PrettyDescriptor(klass.Get()).c_str()); 4268 return false; 4269 } 4270 4271 if (kIsDebugBuild) { 4272 // Ensure super classes are fully resolved prior to resolving fields.. 4273 while (super != nullptr) { 4274 CHECK(super->IsResolved()); 4275 super = super->GetSuperClass(); 4276 } 4277 } 4278 return true; 4279} 4280 4281// Populate the class vtable and itable. Compute return type indices. 4282bool ClassLinker::LinkMethods(Thread* self, Handle<mirror::Class> klass, 4283 Handle<mirror::ObjectArray<mirror::Class>> interfaces, 4284 StackHandleScope<mirror::Class::kImtSize>* out_imt) { 4285 self->AllowThreadSuspension(); 4286 if (klass->IsInterface()) { 4287 // No vtable. 4288 size_t count = klass->NumVirtualMethods(); 4289 if (!IsUint<16>(count)) { 4290 ThrowClassFormatError(klass.Get(), "Too many methods on interface: %zd", count); 4291 return false; 4292 } 4293 for (size_t i = 0; i < count; ++i) { 4294 klass->GetVirtualMethodDuringLinking(i)->SetMethodIndex(i); 4295 } 4296 } else if (!LinkVirtualMethods(self, klass)) { // Link virtual methods first. 4297 return false; 4298 } 4299 return LinkInterfaceMethods(self, klass, interfaces, out_imt); // Link interface method last. 4300} 4301 4302// Comparator for name and signature of a method, used in finding overriding methods. Implementation 4303// avoids the use of handles, if it didn't then rather than compare dex files we could compare dex 4304// caches in the implementation below. 4305class MethodNameAndSignatureComparator FINAL : public ValueObject { 4306 public: 4307 explicit MethodNameAndSignatureComparator(mirror::ArtMethod* method) 4308 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) : 4309 dex_file_(method->GetDexFile()), mid_(&dex_file_->GetMethodId(method->GetDexMethodIndex())), 4310 name_(nullptr), name_len_(0) { 4311 DCHECK(!method->IsProxyMethod()) << PrettyMethod(method); 4312 } 4313 4314 const char* GetName() { 4315 if (name_ == nullptr) { 4316 name_ = dex_file_->StringDataAndUtf16LengthByIdx(mid_->name_idx_, &name_len_); 4317 } 4318 return name_; 4319 } 4320 4321 bool HasSameNameAndSignature(mirror::ArtMethod* other) 4322 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4323 DCHECK(!other->IsProxyMethod()) << PrettyMethod(other); 4324 const DexFile* other_dex_file = other->GetDexFile(); 4325 const DexFile::MethodId& other_mid = other_dex_file->GetMethodId(other->GetDexMethodIndex()); 4326 if (dex_file_ == other_dex_file) { 4327 return mid_->name_idx_ == other_mid.name_idx_ && mid_->proto_idx_ == other_mid.proto_idx_; 4328 } 4329 GetName(); // Only used to make sure its calculated. 4330 uint32_t other_name_len; 4331 const char* other_name = other_dex_file->StringDataAndUtf16LengthByIdx(other_mid.name_idx_, 4332 &other_name_len); 4333 if (name_len_ != other_name_len || strcmp(name_, other_name) != 0) { 4334 return false; 4335 } 4336 return dex_file_->GetMethodSignature(*mid_) == other_dex_file->GetMethodSignature(other_mid); 4337 } 4338 4339 private: 4340 // Dex file for the method to compare against. 4341 const DexFile* const dex_file_; 4342 // MethodId for the method to compare against. 4343 const DexFile::MethodId* const mid_; 4344 // Lazily computed name from the dex file's strings. 4345 const char* name_; 4346 // Lazily computed name length. 4347 uint32_t name_len_; 4348}; 4349 4350class LinkVirtualHashTable { 4351 public: 4352 LinkVirtualHashTable(Handle<mirror::Class> klass, size_t hash_size, uint32_t* hash_table) 4353 : klass_(klass), hash_size_(hash_size), hash_table_(hash_table) { 4354 std::fill(hash_table_, hash_table_ + hash_size_, invalid_index_); 4355 } 4356 void Add(uint32_t virtual_method_index) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4357 mirror::ArtMethod* local_method = klass_->GetVirtualMethodDuringLinking(virtual_method_index); 4358 const char* name = local_method->GetName(); 4359 uint32_t hash = ComputeModifiedUtf8Hash(name); 4360 uint32_t index = hash % hash_size_; 4361 // Linear probe until we have an empty slot. 4362 while (hash_table_[index] != invalid_index_) { 4363 if (++index == hash_size_) { 4364 index = 0; 4365 } 4366 } 4367 hash_table_[index] = virtual_method_index; 4368 } 4369 uint32_t FindAndRemove(MethodNameAndSignatureComparator* comparator) 4370 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4371 const char* name = comparator->GetName(); 4372 uint32_t hash = ComputeModifiedUtf8Hash(name); 4373 size_t index = hash % hash_size_; 4374 while (true) { 4375 const uint32_t value = hash_table_[index]; 4376 // Since linear probe makes continuous blocks, hitting an invalid index means we are done 4377 // the block and can safely assume not found. 4378 if (value == invalid_index_) { 4379 break; 4380 } 4381 if (value != removed_index_) { // This signifies not already overriden. 4382 mirror::ArtMethod* virtual_method = 4383 klass_->GetVirtualMethodDuringLinking(value); 4384 if (comparator->HasSameNameAndSignature(virtual_method->GetInterfaceMethodIfProxy())) { 4385 hash_table_[index] = removed_index_; 4386 return value; 4387 } 4388 } 4389 if (++index == hash_size_) { 4390 index = 0; 4391 } 4392 } 4393 return GetNotFoundIndex(); 4394 } 4395 static uint32_t GetNotFoundIndex() { 4396 return invalid_index_; 4397 } 4398 4399 private: 4400 static const uint32_t invalid_index_; 4401 static const uint32_t removed_index_; 4402 4403 Handle<mirror::Class> klass_; 4404 const size_t hash_size_; 4405 uint32_t* const hash_table_; 4406}; 4407 4408const uint32_t LinkVirtualHashTable::invalid_index_ = std::numeric_limits<uint32_t>::max(); 4409const uint32_t LinkVirtualHashTable::removed_index_ = std::numeric_limits<uint32_t>::max() - 1; 4410 4411bool ClassLinker::LinkVirtualMethods(Thread* self, Handle<mirror::Class> klass) { 4412 const size_t num_virtual_methods = klass->NumVirtualMethods(); 4413 if (klass->HasSuperClass()) { 4414 const size_t super_vtable_length = klass->GetSuperClass()->GetVTableLength(); 4415 const size_t max_count = num_virtual_methods + super_vtable_length; 4416 StackHandleScope<2> hs(self); 4417 Handle<mirror::Class> super_class(hs.NewHandle(klass->GetSuperClass())); 4418 MutableHandle<mirror::ObjectArray<mirror::ArtMethod>> vtable; 4419 if (super_class->ShouldHaveEmbeddedImtAndVTable()) { 4420 vtable = hs.NewHandle(AllocArtMethodArray(self, max_count)); 4421 if (UNLIKELY(vtable.Get() == nullptr)) { 4422 CHECK(self->IsExceptionPending()); // OOME. 4423 return false; 4424 } 4425 for (size_t i = 0; i < super_vtable_length; i++) { 4426 vtable->SetWithoutChecks<false>(i, super_class->GetEmbeddedVTableEntry(i)); 4427 } 4428 if (num_virtual_methods == 0) { 4429 klass->SetVTable(vtable.Get()); 4430 return true; 4431 } 4432 } else { 4433 mirror::ObjectArray<mirror::ArtMethod>* super_vtable = super_class->GetVTable(); 4434 CHECK(super_vtable != nullptr) << PrettyClass(super_class.Get()); 4435 if (num_virtual_methods == 0) { 4436 klass->SetVTable(super_vtable); 4437 return true; 4438 } 4439 vtable = hs.NewHandle(super_vtable->CopyOf(self, max_count)); 4440 if (UNLIKELY(vtable.Get() == nullptr)) { 4441 CHECK(self->IsExceptionPending()); // OOME. 4442 return false; 4443 } 4444 } 4445 // How the algorithm works: 4446 // 1. Populate hash table by adding num_virtual_methods from klass. The values in the hash 4447 // table are: invalid_index for unused slots, index super_vtable_length + i for a virtual 4448 // method which has not been matched to a vtable method, and j if the virtual method at the 4449 // index overrode the super virtual method at index j. 4450 // 2. Loop through super virtual methods, if they overwrite, update hash table to j 4451 // (j < super_vtable_length) to avoid redundant checks. (TODO maybe use this info for reducing 4452 // the need for the initial vtable which we later shrink back down). 4453 // 3. Add non overridden methods to the end of the vtable. 4454 static constexpr size_t kMaxStackHash = 250; 4455 const size_t hash_table_size = num_virtual_methods * 3; 4456 uint32_t* hash_table_ptr; 4457 std::unique_ptr<uint32_t[]> hash_heap_storage; 4458 if (hash_table_size <= kMaxStackHash) { 4459 hash_table_ptr = reinterpret_cast<uint32_t*>( 4460 alloca(hash_table_size * sizeof(*hash_table_ptr))); 4461 } else { 4462 hash_heap_storage.reset(new uint32_t[hash_table_size]); 4463 hash_table_ptr = hash_heap_storage.get(); 4464 } 4465 LinkVirtualHashTable hash_table(klass, hash_table_size, hash_table_ptr); 4466 // Add virtual methods to the hash table. 4467 for (size_t i = 0; i < num_virtual_methods; ++i) { 4468 hash_table.Add(i); 4469 } 4470 // Loop through each super vtable method and see if they are overriden by a method we added to 4471 // the hash table. 4472 for (size_t j = 0; j < super_vtable_length; ++j) { 4473 // Search the hash table to see if we are overidden by any method. 4474 mirror::ArtMethod* super_method = vtable->GetWithoutChecks(j); 4475 MethodNameAndSignatureComparator super_method_name_comparator( 4476 super_method->GetInterfaceMethodIfProxy()); 4477 uint32_t hash_index = hash_table.FindAndRemove(&super_method_name_comparator); 4478 if (hash_index != hash_table.GetNotFoundIndex()) { 4479 mirror::ArtMethod* virtual_method = klass->GetVirtualMethodDuringLinking(hash_index); 4480 if (klass->CanAccessMember(super_method->GetDeclaringClass(), 4481 super_method->GetAccessFlags())) { 4482 if (super_method->IsFinal()) { 4483 ThrowLinkageError(klass.Get(), "Method %s overrides final method in class %s", 4484 PrettyMethod(virtual_method).c_str(), 4485 super_method->GetDeclaringClassDescriptor()); 4486 return false; 4487 } 4488 vtable->SetWithoutChecks<false>(j, virtual_method); 4489 virtual_method->SetMethodIndex(j); 4490 } else { 4491 LOG(WARNING) << "Before Android 4.1, method " << PrettyMethod(virtual_method) 4492 << " would have incorrectly overridden the package-private method in " 4493 << PrettyDescriptor(super_method->GetDeclaringClassDescriptor()); 4494 } 4495 } 4496 } 4497 // Add the non overridden methods at the end. 4498 size_t actual_count = super_vtable_length; 4499 for (size_t i = 0; i < num_virtual_methods; ++i) { 4500 mirror::ArtMethod* local_method = klass->GetVirtualMethodDuringLinking(i); 4501 size_t method_idx = local_method->GetMethodIndexDuringLinking(); 4502 if (method_idx < super_vtable_length && 4503 local_method == vtable->GetWithoutChecks(method_idx)) { 4504 continue; 4505 } 4506 vtable->SetWithoutChecks<false>(actual_count, local_method); 4507 local_method->SetMethodIndex(actual_count); 4508 ++actual_count; 4509 } 4510 if (!IsUint<16>(actual_count)) { 4511 ThrowClassFormatError(klass.Get(), "Too many methods defined on class: %zd", actual_count); 4512 return false; 4513 } 4514 // Shrink vtable if possible 4515 CHECK_LE(actual_count, max_count); 4516 if (actual_count < max_count) { 4517 vtable.Assign(vtable->CopyOf(self, actual_count)); 4518 if (UNLIKELY(vtable.Get() == nullptr)) { 4519 CHECK(self->IsExceptionPending()); // OOME. 4520 return false; 4521 } 4522 } 4523 klass->SetVTable(vtable.Get()); 4524 } else { 4525 CHECK_EQ(klass.Get(), GetClassRoot(kJavaLangObject)); 4526 if (!IsUint<16>(num_virtual_methods)) { 4527 ThrowClassFormatError(klass.Get(), "Too many methods: %d", 4528 static_cast<int>(num_virtual_methods)); 4529 return false; 4530 } 4531 mirror::ObjectArray<mirror::ArtMethod>* vtable = AllocArtMethodArray(self, num_virtual_methods); 4532 if (UNLIKELY(vtable == nullptr)) { 4533 CHECK(self->IsExceptionPending()); // OOME. 4534 return false; 4535 } 4536 for (size_t i = 0; i < num_virtual_methods; ++i) { 4537 mirror::ArtMethod* virtual_method = klass->GetVirtualMethodDuringLinking(i); 4538 vtable->SetWithoutChecks<false>(i, virtual_method); 4539 virtual_method->SetMethodIndex(i & 0xFFFF); 4540 } 4541 klass->SetVTable(vtable); 4542 } 4543 return true; 4544} 4545 4546bool ClassLinker::LinkInterfaceMethods(Thread* self, Handle<mirror::Class> klass, 4547 Handle<mirror::ObjectArray<mirror::Class>> interfaces, 4548 StackHandleScope<mirror::Class::kImtSize>* out_imt) { 4549 StackHandleScope<3> hs(self); 4550 Runtime* const runtime = Runtime::Current(); 4551 const bool has_superclass = klass->HasSuperClass(); 4552 const size_t super_ifcount = has_superclass ? klass->GetSuperClass()->GetIfTableCount() : 0U; 4553 const bool have_interfaces = interfaces.Get() != nullptr; 4554 const size_t num_interfaces = 4555 have_interfaces ? interfaces->GetLength() : klass->NumDirectInterfaces(); 4556 if (num_interfaces == 0) { 4557 if (super_ifcount == 0) { 4558 // Class implements no interfaces. 4559 DCHECK_EQ(klass->GetIfTableCount(), 0); 4560 DCHECK(klass->GetIfTable() == nullptr); 4561 return true; 4562 } 4563 // Class implements same interfaces as parent, are any of these not marker interfaces? 4564 bool has_non_marker_interface = false; 4565 mirror::IfTable* super_iftable = klass->GetSuperClass()->GetIfTable(); 4566 for (size_t i = 0; i < super_ifcount; ++i) { 4567 if (super_iftable->GetMethodArrayCount(i) > 0) { 4568 has_non_marker_interface = true; 4569 break; 4570 } 4571 } 4572 // Class just inherits marker interfaces from parent so recycle parent's iftable. 4573 if (!has_non_marker_interface) { 4574 klass->SetIfTable(super_iftable); 4575 return true; 4576 } 4577 } 4578 size_t ifcount = super_ifcount + num_interfaces; 4579 for (size_t i = 0; i < num_interfaces; i++) { 4580 mirror::Class* interface = have_interfaces ? 4581 interfaces->GetWithoutChecks(i) : mirror::Class::GetDirectInterface(self, klass, i); 4582 DCHECK(interface != nullptr); 4583 if (UNLIKELY(!interface->IsInterface())) { 4584 std::string temp; 4585 ThrowIncompatibleClassChangeError(klass.Get(), "Class %s implements non-interface class %s", 4586 PrettyDescriptor(klass.Get()).c_str(), 4587 PrettyDescriptor(interface->GetDescriptor(&temp)).c_str()); 4588 return false; 4589 } 4590 ifcount += interface->GetIfTableCount(); 4591 } 4592 MutableHandle<mirror::IfTable> iftable(hs.NewHandle(AllocIfTable(self, ifcount))); 4593 if (UNLIKELY(iftable.Get() == nullptr)) { 4594 CHECK(self->IsExceptionPending()); // OOME. 4595 return false; 4596 } 4597 if (super_ifcount != 0) { 4598 mirror::IfTable* super_iftable = klass->GetSuperClass()->GetIfTable(); 4599 for (size_t i = 0; i < super_ifcount; i++) { 4600 mirror::Class* super_interface = super_iftable->GetInterface(i); 4601 iftable->SetInterface(i, super_interface); 4602 } 4603 } 4604 self->AllowThreadSuspension(); 4605 // Flatten the interface inheritance hierarchy. 4606 size_t idx = super_ifcount; 4607 for (size_t i = 0; i < num_interfaces; i++) { 4608 mirror::Class* interface = have_interfaces ? interfaces->Get(i) : 4609 mirror::Class::GetDirectInterface(self, klass, i); 4610 // Check if interface is already in iftable 4611 bool duplicate = false; 4612 for (size_t j = 0; j < idx; j++) { 4613 mirror::Class* existing_interface = iftable->GetInterface(j); 4614 if (existing_interface == interface) { 4615 duplicate = true; 4616 break; 4617 } 4618 } 4619 if (!duplicate) { 4620 // Add this non-duplicate interface. 4621 iftable->SetInterface(idx++, interface); 4622 // Add this interface's non-duplicate super-interfaces. 4623 for (int32_t j = 0; j < interface->GetIfTableCount(); j++) { 4624 mirror::Class* super_interface = interface->GetIfTable()->GetInterface(j); 4625 bool super_duplicate = false; 4626 for (size_t k = 0; k < idx; k++) { 4627 mirror::Class* existing_interface = iftable->GetInterface(k); 4628 if (existing_interface == super_interface) { 4629 super_duplicate = true; 4630 break; 4631 } 4632 } 4633 if (!super_duplicate) { 4634 iftable->SetInterface(idx++, super_interface); 4635 } 4636 } 4637 } 4638 } 4639 self->AllowThreadSuspension(); 4640 // Shrink iftable in case duplicates were found 4641 if (idx < ifcount) { 4642 DCHECK_NE(num_interfaces, 0U); 4643 iftable.Assign(down_cast<mirror::IfTable*>(iftable->CopyOf(self, idx * mirror::IfTable::kMax))); 4644 if (UNLIKELY(iftable.Get() == nullptr)) { 4645 CHECK(self->IsExceptionPending()); // OOME. 4646 return false; 4647 } 4648 ifcount = idx; 4649 } else { 4650 DCHECK_EQ(idx, ifcount); 4651 } 4652 klass->SetIfTable(iftable.Get()); 4653 // If we're an interface, we don't need the vtable pointers, so we're done. 4654 if (klass->IsInterface()) { 4655 return true; 4656 } 4657 size_t miranda_list_size = 0; 4658 size_t max_miranda_methods = 0; // The max size of miranda_list. 4659 for (size_t i = 0; i < ifcount; ++i) { 4660 max_miranda_methods += iftable->GetInterface(i)->NumVirtualMethods(); 4661 } 4662 MutableHandle<mirror::ObjectArray<mirror::ArtMethod>> 4663 miranda_list(hs.NewHandle(AllocArtMethodArray(self, max_miranda_methods))); 4664 MutableHandle<mirror::ObjectArray<mirror::ArtMethod>> vtable( 4665 hs.NewHandle(klass->GetVTableDuringLinking())); 4666 // Copy the IMT from the super class if possible. 4667 bool extend_super_iftable = false; 4668 if (has_superclass) { 4669 mirror::Class* super_class = klass->GetSuperClass(); 4670 extend_super_iftable = true; 4671 if (super_class->ShouldHaveEmbeddedImtAndVTable()) { 4672 for (size_t i = 0; i < mirror::Class::kImtSize; ++i) { 4673 out_imt->SetReference(i, super_class->GetEmbeddedImTableEntry(i)); 4674 } 4675 } else { 4676 // No imt in the super class, need to reconstruct from the iftable. 4677 mirror::IfTable* if_table = super_class->GetIfTable(); 4678 mirror::ArtMethod* conflict_method = runtime->GetImtConflictMethod(); 4679 const size_t length = super_class->GetIfTableCount(); 4680 for (size_t i = 0; i < length; ++i) { 4681 mirror::Class* interface = iftable->GetInterface(i); 4682 const size_t num_virtuals = interface->NumVirtualMethods(); 4683 const size_t method_array_count = if_table->GetMethodArrayCount(i); 4684 DCHECK_EQ(num_virtuals, method_array_count); 4685 if (method_array_count == 0) { 4686 continue; 4687 } 4688 mirror::ObjectArray<mirror::ArtMethod>* method_array = if_table->GetMethodArray(i); 4689 for (size_t j = 0; j < num_virtuals; ++j) { 4690 mirror::ArtMethod* method = method_array->GetWithoutChecks(j); 4691 if (method->IsMiranda()) { 4692 continue; 4693 } 4694 mirror::ArtMethod* interface_method = interface->GetVirtualMethod(j); 4695 uint32_t imt_index = interface_method->GetDexMethodIndex() % mirror::Class::kImtSize; 4696 mirror::ArtMethod* imt_ref = out_imt->GetReference(imt_index)->AsArtMethod(); 4697 if (imt_ref == runtime->GetImtUnimplementedMethod()) { 4698 out_imt->SetReference(imt_index, method); 4699 } else if (imt_ref != conflict_method) { 4700 out_imt->SetReference(imt_index, conflict_method); 4701 } 4702 } 4703 } 4704 } 4705 } 4706 for (size_t i = 0; i < ifcount; ++i) { 4707 self->AllowThreadSuspension(); 4708 size_t num_methods = iftable->GetInterface(i)->NumVirtualMethods(); 4709 if (num_methods > 0) { 4710 StackHandleScope<2> hs2(self); 4711 const bool is_super = i < super_ifcount; 4712 const bool super_interface = is_super && extend_super_iftable; 4713 Handle<mirror::ObjectArray<mirror::ArtMethod>> method_array; 4714 Handle<mirror::ObjectArray<mirror::ArtMethod>> input_array; 4715 if (super_interface) { 4716 mirror::IfTable* if_table = klass->GetSuperClass()->GetIfTable(); 4717 DCHECK(if_table != nullptr); 4718 DCHECK(if_table->GetMethodArray(i) != nullptr); 4719 // If we are working on a super interface, try extending the existing method array. 4720 method_array = hs2.NewHandle(if_table->GetMethodArray(i)->Clone(self)-> 4721 AsObjectArray<mirror::ArtMethod>()); 4722 // We are overwriting a super class interface, try to only virtual methods instead of the 4723 // whole vtable. 4724 input_array = hs2.NewHandle(klass->GetVirtualMethods()); 4725 } else { 4726 method_array = hs2.NewHandle(AllocArtMethodArray(self, num_methods)); 4727 // A new interface, we need the whole vtable incase a new interface method is implemented 4728 // in the whole superclass. 4729 input_array = vtable; 4730 } 4731 if (UNLIKELY(method_array.Get() == nullptr)) { 4732 CHECK(self->IsExceptionPending()); // OOME. 4733 return false; 4734 } 4735 iftable->SetMethodArray(i, method_array.Get()); 4736 if (input_array.Get() == nullptr) { 4737 // If the added virtual methods is empty, do nothing. 4738 DCHECK(super_interface); 4739 continue; 4740 } 4741 for (size_t j = 0; j < num_methods; ++j) { 4742 mirror::ArtMethod* interface_method = iftable->GetInterface(i)->GetVirtualMethod(j); 4743 MethodNameAndSignatureComparator interface_name_comparator( 4744 interface_method->GetInterfaceMethodIfProxy()); 4745 int32_t k; 4746 // For each method listed in the interface's method list, find the 4747 // matching method in our class's method list. We want to favor the 4748 // subclass over the superclass, which just requires walking 4749 // back from the end of the vtable. (This only matters if the 4750 // superclass defines a private method and this class redefines 4751 // it -- otherwise it would use the same vtable slot. In .dex files 4752 // those don't end up in the virtual method table, so it shouldn't 4753 // matter which direction we go. We walk it backward anyway.) 4754 for (k = input_array->GetLength() - 1; k >= 0; --k) { 4755 mirror::ArtMethod* vtable_method = input_array->GetWithoutChecks(k); 4756 mirror::ArtMethod* vtable_method_for_name_comparison = 4757 vtable_method->GetInterfaceMethodIfProxy(); 4758 if (interface_name_comparator.HasSameNameAndSignature( 4759 vtable_method_for_name_comparison)) { 4760 if (!vtable_method->IsAbstract() && !vtable_method->IsPublic()) { 4761 ThrowIllegalAccessError( 4762 klass.Get(), 4763 "Method '%s' implementing interface method '%s' is not public", 4764 PrettyMethod(vtable_method).c_str(), 4765 PrettyMethod(interface_method).c_str()); 4766 return false; 4767 } 4768 method_array->SetWithoutChecks<false>(j, vtable_method); 4769 // Place method in imt if entry is empty, place conflict otherwise. 4770 uint32_t imt_index = interface_method->GetDexMethodIndex() % mirror::Class::kImtSize; 4771 mirror::ArtMethod* imt_ref = out_imt->GetReference(imt_index)->AsArtMethod(); 4772 mirror::ArtMethod* conflict_method = runtime->GetImtConflictMethod(); 4773 if (imt_ref == runtime->GetImtUnimplementedMethod()) { 4774 out_imt->SetReference(imt_index, vtable_method); 4775 } else if (imt_ref != conflict_method) { 4776 // If we are not a conflict and we have the same signature and name as the imt entry, 4777 // it must be that we overwrote a superclass vtable entry. 4778 MethodNameAndSignatureComparator imt_ref_name_comparator( 4779 imt_ref->GetInterfaceMethodIfProxy()); 4780 if (imt_ref_name_comparator.HasSameNameAndSignature( 4781 vtable_method_for_name_comparison)) { 4782 out_imt->SetReference(imt_index, vtable_method); 4783 } else { 4784 out_imt->SetReference(imt_index, conflict_method); 4785 } 4786 } 4787 break; 4788 } 4789 } 4790 if (k < 0 && !super_interface) { 4791 mirror::ArtMethod* miranda_method = nullptr; 4792 for (size_t l = 0; l < miranda_list_size; ++l) { 4793 mirror::ArtMethod* mir_method = miranda_list->Get(l); 4794 if (interface_name_comparator.HasSameNameAndSignature(mir_method)) { 4795 miranda_method = mir_method; 4796 break; 4797 } 4798 } 4799 if (miranda_method == nullptr) { 4800 // Point the interface table at a phantom slot. 4801 miranda_method = interface_method->Clone(self)->AsArtMethod(); 4802 if (UNLIKELY(miranda_method == nullptr)) { 4803 CHECK(self->IsExceptionPending()); // OOME. 4804 return false; 4805 } 4806 DCHECK_LT(miranda_list_size, max_miranda_methods); 4807 miranda_list->Set<false>(miranda_list_size++, miranda_method); 4808 } 4809 method_array->SetWithoutChecks<false>(j, miranda_method); 4810 } 4811 } 4812 } 4813 } 4814 if (miranda_list_size > 0) { 4815 int old_method_count = klass->NumVirtualMethods(); 4816 int new_method_count = old_method_count + miranda_list_size; 4817 mirror::ObjectArray<mirror::ArtMethod>* virtuals; 4818 if (old_method_count == 0) { 4819 virtuals = AllocArtMethodArray(self, new_method_count); 4820 } else { 4821 virtuals = klass->GetVirtualMethods()->CopyOf(self, new_method_count); 4822 } 4823 if (UNLIKELY(virtuals == nullptr)) { 4824 CHECK(self->IsExceptionPending()); // OOME. 4825 return false; 4826 } 4827 klass->SetVirtualMethods(virtuals); 4828 4829 int old_vtable_count = vtable->GetLength(); 4830 int new_vtable_count = old_vtable_count + miranda_list_size; 4831 vtable.Assign(vtable->CopyOf(self, new_vtable_count)); 4832 if (UNLIKELY(vtable.Get() == nullptr)) { 4833 CHECK(self->IsExceptionPending()); // OOME. 4834 return false; 4835 } 4836 for (size_t i = 0; i < miranda_list_size; ++i) { 4837 mirror::ArtMethod* method = miranda_list->Get(i); 4838 // Leave the declaring class alone as type indices are relative to it 4839 method->SetAccessFlags(method->GetAccessFlags() | kAccMiranda); 4840 method->SetMethodIndex(0xFFFF & (old_vtable_count + i)); 4841 klass->SetVirtualMethod(old_method_count + i, method); 4842 vtable->SetWithoutChecks<false>(old_vtable_count + i, method); 4843 } 4844 // TODO: do not assign to the vtable field until it is fully constructed. 4845 klass->SetVTable(vtable.Get()); 4846 } 4847 4848 if (kIsDebugBuild) { 4849 mirror::ObjectArray<mirror::ArtMethod>* check_vtable = klass->GetVTableDuringLinking(); 4850 for (int i = 0; i < check_vtable->GetLength(); ++i) { 4851 CHECK(check_vtable->GetWithoutChecks(i) != nullptr); 4852 } 4853 } 4854 4855 self->AllowThreadSuspension(); 4856 return true; 4857} 4858 4859bool ClassLinker::LinkInstanceFields(Thread* self, Handle<mirror::Class> klass) { 4860 CHECK(klass.Get() != nullptr); 4861 return LinkFields(self, klass, false, nullptr); 4862} 4863 4864bool ClassLinker::LinkStaticFields(Thread* self, Handle<mirror::Class> klass, size_t* class_size) { 4865 CHECK(klass.Get() != nullptr); 4866 return LinkFields(self, klass, true, class_size); 4867} 4868 4869struct LinkFieldsComparator { 4870 explicit LinkFieldsComparator() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4871 } 4872 // No thread safety analysis as will be called from STL. Checked lock held in constructor. 4873 bool operator()(ArtField* field1, ArtField* field2) 4874 NO_THREAD_SAFETY_ANALYSIS { 4875 // First come reference fields, then 64-bit, then 32-bit, and then 16-bit, then finally 8-bit. 4876 Primitive::Type type1 = field1->GetTypeAsPrimitiveType(); 4877 Primitive::Type type2 = field2->GetTypeAsPrimitiveType(); 4878 if (type1 != type2) { 4879 if (type1 == Primitive::kPrimNot) { 4880 // Reference always goes first. 4881 return true; 4882 } 4883 if (type2 == Primitive::kPrimNot) { 4884 // Reference always goes first. 4885 return false; 4886 } 4887 size_t size1 = Primitive::ComponentSize(type1); 4888 size_t size2 = Primitive::ComponentSize(type2); 4889 if (size1 != size2) { 4890 // Larger primitive types go first. 4891 return size1 > size2; 4892 } 4893 // Primitive types differ but sizes match. Arbitrarily order by primitive type. 4894 return type1 < type2; 4895 } 4896 // Same basic group? Then sort by dex field index. This is guaranteed to be sorted 4897 // by name and for equal names by type id index. 4898 // NOTE: This works also for proxies. Their static fields are assigned appropriate indexes. 4899 return field1->GetDexFieldIndex() < field2->GetDexFieldIndex(); 4900 } 4901}; 4902 4903bool ClassLinker::LinkFields(Thread* self, Handle<mirror::Class> klass, bool is_static, 4904 size_t* class_size) { 4905 self->AllowThreadSuspension(); 4906 const size_t num_fields = is_static ? klass->NumStaticFields() : klass->NumInstanceFields(); 4907 ArtField* const fields = is_static ? klass->GetSFields() : klass->GetIFields(); 4908 4909 // Initialize field_offset 4910 MemberOffset field_offset(0); 4911 if (is_static) { 4912 field_offset = klass->GetFirstReferenceStaticFieldOffsetDuringLinking(); 4913 } else { 4914 mirror::Class* super_class = klass->GetSuperClass(); 4915 if (super_class != nullptr) { 4916 CHECK(super_class->IsResolved()) 4917 << PrettyClass(klass.Get()) << " " << PrettyClass(super_class); 4918 field_offset = MemberOffset(super_class->GetObjectSize()); 4919 } 4920 } 4921 4922 CHECK_EQ(num_fields == 0, fields == nullptr) << PrettyClass(klass.Get()); 4923 4924 // we want a relatively stable order so that adding new fields 4925 // minimizes disruption of C++ version such as Class and Method. 4926 std::deque<ArtField*> grouped_and_sorted_fields; 4927 const char* old_no_suspend_cause = self->StartAssertNoThreadSuspension( 4928 "Naked ArtField references in deque"); 4929 for (size_t i = 0; i < num_fields; i++) { 4930 grouped_and_sorted_fields.push_back(&fields[i]); 4931 } 4932 std::sort(grouped_and_sorted_fields.begin(), grouped_and_sorted_fields.end(), 4933 LinkFieldsComparator()); 4934 4935 // References should be at the front. 4936 size_t current_field = 0; 4937 size_t num_reference_fields = 0; 4938 FieldGaps gaps; 4939 4940 for (; current_field < num_fields; current_field++) { 4941 ArtField* field = grouped_and_sorted_fields.front(); 4942 Primitive::Type type = field->GetTypeAsPrimitiveType(); 4943 bool isPrimitive = type != Primitive::kPrimNot; 4944 if (isPrimitive) { 4945 break; // past last reference, move on to the next phase 4946 } 4947 if (UNLIKELY(!IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>( 4948 field_offset.Uint32Value()))) { 4949 MemberOffset old_offset = field_offset; 4950 field_offset = MemberOffset(RoundUp(field_offset.Uint32Value(), 4)); 4951 AddFieldGap(old_offset.Uint32Value(), field_offset.Uint32Value(), &gaps); 4952 } 4953 DCHECK(IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>(field_offset.Uint32Value())); 4954 grouped_and_sorted_fields.pop_front(); 4955 num_reference_fields++; 4956 field->SetOffset(field_offset); 4957 field_offset = MemberOffset(field_offset.Uint32Value() + 4958 sizeof(mirror::HeapReference<mirror::Object>)); 4959 } 4960 // Gaps are stored as a max heap which means that we must shuffle from largest to smallest 4961 // otherwise we could end up with suboptimal gap fills. 4962 ShuffleForward<8>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 4963 ShuffleForward<4>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 4964 ShuffleForward<2>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 4965 ShuffleForward<1>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 4966 CHECK(grouped_and_sorted_fields.empty()) << "Missed " << grouped_and_sorted_fields.size() << 4967 " fields."; 4968 self->EndAssertNoThreadSuspension(old_no_suspend_cause); 4969 4970 // We lie to the GC about the java.lang.ref.Reference.referent field, so it doesn't scan it. 4971 if (!is_static && klass->DescriptorEquals("Ljava/lang/ref/Reference;")) { 4972 // We know there are no non-reference fields in the Reference classes, and we know 4973 // that 'referent' is alphabetically last, so this is easy... 4974 CHECK_EQ(num_reference_fields, num_fields) << PrettyClass(klass.Get()); 4975 CHECK_STREQ(fields[num_fields - 1].GetName(), "referent") << PrettyClass(klass.Get()); 4976 --num_reference_fields; 4977 } 4978 4979 size_t size = field_offset.Uint32Value(); 4980 // Update klass 4981 if (is_static) { 4982 klass->SetNumReferenceStaticFields(num_reference_fields); 4983 *class_size = size; 4984 } else { 4985 klass->SetNumReferenceInstanceFields(num_reference_fields); 4986 if (!klass->IsVariableSize()) { 4987 if (klass->DescriptorEquals("Ljava/lang/reflect/ArtMethod;")) { 4988 size_t pointer_size = GetInstructionSetPointerSize(Runtime::Current()->GetInstructionSet()); 4989 klass->SetObjectSize(mirror::ArtMethod::InstanceSize(pointer_size)); 4990 } else { 4991 std::string temp; 4992 DCHECK_GE(size, sizeof(mirror::Object)) << klass->GetDescriptor(&temp); 4993 size_t previous_size = klass->GetObjectSize(); 4994 if (previous_size != 0) { 4995 // Make sure that we didn't originally have an incorrect size. 4996 CHECK_EQ(previous_size, size) << klass->GetDescriptor(&temp); 4997 } 4998 klass->SetObjectSize(size); 4999 } 5000 } 5001 } 5002 5003 if (kIsDebugBuild) { 5004 // Make sure that the fields array is ordered by name but all reference 5005 // offsets are at the beginning as far as alignment allows. 5006 MemberOffset start_ref_offset = is_static 5007 ? klass->GetFirstReferenceStaticFieldOffsetDuringLinking() 5008 : klass->GetFirstReferenceInstanceFieldOffset(); 5009 MemberOffset end_ref_offset(start_ref_offset.Uint32Value() + 5010 num_reference_fields * 5011 sizeof(mirror::HeapReference<mirror::Object>)); 5012 MemberOffset current_ref_offset = start_ref_offset; 5013 for (size_t i = 0; i < num_fields; i++) { 5014 ArtField* field = &fields[i]; 5015 VLOG(class_linker) << "LinkFields: " << (is_static ? "static" : "instance") 5016 << " class=" << PrettyClass(klass.Get()) << " field=" << PrettyField(field) << " offset=" 5017 << field->GetOffset(); 5018 if (i != 0) { 5019 ArtField* const prev_field = &fields[i - 1]; 5020 // NOTE: The field names can be the same. This is not possible in the Java language 5021 // but it's valid Java/dex bytecode and for example proguard can generate such bytecode. 5022 CHECK_LE(strcmp(prev_field->GetName(), field->GetName()), 0); 5023 } 5024 Primitive::Type type = field->GetTypeAsPrimitiveType(); 5025 bool is_primitive = type != Primitive::kPrimNot; 5026 if (klass->DescriptorEquals("Ljava/lang/ref/Reference;") && 5027 strcmp("referent", field->GetName()) == 0) { 5028 is_primitive = true; // We lied above, so we have to expect a lie here. 5029 } 5030 MemberOffset offset = field->GetOffsetDuringLinking(); 5031 if (is_primitive) { 5032 if (offset.Uint32Value() < end_ref_offset.Uint32Value()) { 5033 // Shuffled before references. 5034 size_t type_size = Primitive::ComponentSize(type); 5035 CHECK_LT(type_size, sizeof(mirror::HeapReference<mirror::Object>)); 5036 CHECK_LT(offset.Uint32Value(), start_ref_offset.Uint32Value()); 5037 CHECK_LE(offset.Uint32Value() + type_size, start_ref_offset.Uint32Value()); 5038 CHECK(!IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>(offset.Uint32Value())); 5039 } 5040 } else { 5041 CHECK_EQ(current_ref_offset.Uint32Value(), offset.Uint32Value()); 5042 current_ref_offset = MemberOffset(current_ref_offset.Uint32Value() + 5043 sizeof(mirror::HeapReference<mirror::Object>)); 5044 } 5045 } 5046 CHECK_EQ(current_ref_offset.Uint32Value(), end_ref_offset.Uint32Value()); 5047 } 5048 return true; 5049} 5050 5051// Set the bitmap of reference instance field offsets. 5052void ClassLinker::CreateReferenceInstanceOffsets(Handle<mirror::Class> klass) { 5053 uint32_t reference_offsets = 0; 5054 mirror::Class* super_class = klass->GetSuperClass(); 5055 // Leave the reference offsets as 0 for mirror::Object (the class field is handled specially). 5056 if (super_class != nullptr) { 5057 reference_offsets = super_class->GetReferenceInstanceOffsets(); 5058 // Compute reference offsets unless our superclass overflowed. 5059 if (reference_offsets != mirror::Class::kClassWalkSuper) { 5060 size_t num_reference_fields = klass->NumReferenceInstanceFieldsDuringLinking(); 5061 if (num_reference_fields != 0u) { 5062 // All of the fields that contain object references are guaranteed be grouped in memory 5063 // starting at an appropriately aligned address after super class object data. 5064 uint32_t start_offset = RoundUp(super_class->GetObjectSize(), 5065 sizeof(mirror::HeapReference<mirror::Object>)); 5066 uint32_t start_bit = (start_offset - mirror::kObjectHeaderSize) / 5067 sizeof(mirror::HeapReference<mirror::Object>); 5068 if (start_bit + num_reference_fields > 32) { 5069 reference_offsets = mirror::Class::kClassWalkSuper; 5070 } else { 5071 reference_offsets |= (0xffffffffu << start_bit) & 5072 (0xffffffffu >> (32 - (start_bit + num_reference_fields))); 5073 } 5074 } 5075 } 5076 } 5077 klass->SetReferenceInstanceOffsets(reference_offsets); 5078} 5079 5080mirror::String* ClassLinker::ResolveString(const DexFile& dex_file, uint32_t string_idx, 5081 Handle<mirror::DexCache> dex_cache) { 5082 DCHECK(dex_cache.Get() != nullptr); 5083 mirror::String* resolved = dex_cache->GetResolvedString(string_idx); 5084 if (resolved != nullptr) { 5085 return resolved; 5086 } 5087 uint32_t utf16_length; 5088 const char* utf8_data = dex_file.StringDataAndUtf16LengthByIdx(string_idx, &utf16_length); 5089 mirror::String* string = intern_table_->InternStrong(utf16_length, utf8_data); 5090 dex_cache->SetResolvedString(string_idx, string); 5091 return string; 5092} 5093 5094mirror::Class* ClassLinker::ResolveType(const DexFile& dex_file, uint16_t type_idx, 5095 mirror::Class* referrer) { 5096 StackHandleScope<2> hs(Thread::Current()); 5097 Handle<mirror::DexCache> dex_cache(hs.NewHandle(referrer->GetDexCache())); 5098 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(referrer->GetClassLoader())); 5099 return ResolveType(dex_file, type_idx, dex_cache, class_loader); 5100} 5101 5102mirror::Class* ClassLinker::ResolveType(const DexFile& dex_file, uint16_t type_idx, 5103 Handle<mirror::DexCache> dex_cache, 5104 Handle<mirror::ClassLoader> class_loader) { 5105 DCHECK(dex_cache.Get() != nullptr); 5106 mirror::Class* resolved = dex_cache->GetResolvedType(type_idx); 5107 if (resolved == nullptr) { 5108 Thread* self = Thread::Current(); 5109 const char* descriptor = dex_file.StringByTypeIdx(type_idx); 5110 resolved = FindClass(self, descriptor, class_loader); 5111 if (resolved != nullptr) { 5112 // TODO: we used to throw here if resolved's class loader was not the 5113 // boot class loader. This was to permit different classes with the 5114 // same name to be loaded simultaneously by different loaders 5115 dex_cache->SetResolvedType(type_idx, resolved); 5116 } else { 5117 CHECK(self->IsExceptionPending()) 5118 << "Expected pending exception for failed resolution of: " << descriptor; 5119 // Convert a ClassNotFoundException to a NoClassDefFoundError. 5120 StackHandleScope<1> hs(self); 5121 Handle<mirror::Throwable> cause(hs.NewHandle(self->GetException())); 5122 if (cause->InstanceOf(GetClassRoot(kJavaLangClassNotFoundException))) { 5123 DCHECK(resolved == nullptr); // No Handle needed to preserve resolved. 5124 self->ClearException(); 5125 ThrowNoClassDefFoundError("Failed resolution of: %s", descriptor); 5126 self->GetException()->SetCause(cause.Get()); 5127 } 5128 } 5129 } 5130 DCHECK((resolved == nullptr) || resolved->IsResolved() || resolved->IsErroneous()) 5131 << PrettyDescriptor(resolved) << " " << resolved->GetStatus(); 5132 return resolved; 5133} 5134 5135mirror::ArtMethod* ClassLinker::ResolveMethod(const DexFile& dex_file, uint32_t method_idx, 5136 Handle<mirror::DexCache> dex_cache, 5137 Handle<mirror::ClassLoader> class_loader, 5138 Handle<mirror::ArtMethod> referrer, 5139 InvokeType type) { 5140 DCHECK(dex_cache.Get() != nullptr); 5141 // Check for hit in the dex cache. 5142 mirror::ArtMethod* resolved = dex_cache->GetResolvedMethod(method_idx); 5143 if (resolved != nullptr && !resolved->IsRuntimeMethod()) { 5144 return resolved; 5145 } 5146 // Fail, get the declaring class. 5147 const DexFile::MethodId& method_id = dex_file.GetMethodId(method_idx); 5148 mirror::Class* klass = ResolveType(dex_file, method_id.class_idx_, dex_cache, class_loader); 5149 if (klass == nullptr) { 5150 DCHECK(Thread::Current()->IsExceptionPending()); 5151 return nullptr; 5152 } 5153 // Scan using method_idx, this saves string compares but will only hit for matching dex 5154 // caches/files. 5155 switch (type) { 5156 case kDirect: // Fall-through. 5157 case kStatic: 5158 resolved = klass->FindDirectMethod(dex_cache.Get(), method_idx); 5159 break; 5160 case kInterface: 5161 resolved = klass->FindInterfaceMethod(dex_cache.Get(), method_idx); 5162 DCHECK(resolved == nullptr || resolved->GetDeclaringClass()->IsInterface()); 5163 break; 5164 case kSuper: // Fall-through. 5165 case kVirtual: 5166 resolved = klass->FindVirtualMethod(dex_cache.Get(), method_idx); 5167 break; 5168 default: 5169 LOG(FATAL) << "Unreachable - invocation type: " << type; 5170 UNREACHABLE(); 5171 } 5172 if (resolved == nullptr) { 5173 // Search by name, which works across dex files. 5174 const char* name = dex_file.StringDataByIdx(method_id.name_idx_); 5175 const Signature signature = dex_file.GetMethodSignature(method_id); 5176 switch (type) { 5177 case kDirect: // Fall-through. 5178 case kStatic: 5179 resolved = klass->FindDirectMethod(name, signature); 5180 break; 5181 case kInterface: 5182 resolved = klass->FindInterfaceMethod(name, signature); 5183 DCHECK(resolved == nullptr || resolved->GetDeclaringClass()->IsInterface()); 5184 break; 5185 case kSuper: // Fall-through. 5186 case kVirtual: 5187 resolved = klass->FindVirtualMethod(name, signature); 5188 break; 5189 } 5190 } 5191 // If we found a method, check for incompatible class changes. 5192 if (LIKELY(resolved != nullptr && !resolved->CheckIncompatibleClassChange(type))) { 5193 // Be a good citizen and update the dex cache to speed subsequent calls. 5194 dex_cache->SetResolvedMethod(method_idx, resolved); 5195 return resolved; 5196 } else { 5197 // If we had a method, it's an incompatible-class-change error. 5198 if (resolved != nullptr) { 5199 ThrowIncompatibleClassChangeError(type, resolved->GetInvokeType(), resolved, referrer.Get()); 5200 } else { 5201 // We failed to find the method which means either an access error, an incompatible class 5202 // change, or no such method. First try to find the method among direct and virtual methods. 5203 const char* name = dex_file.StringDataByIdx(method_id.name_idx_); 5204 const Signature signature = dex_file.GetMethodSignature(method_id); 5205 switch (type) { 5206 case kDirect: 5207 case kStatic: 5208 resolved = klass->FindVirtualMethod(name, signature); 5209 // Note: kDirect and kStatic are also mutually exclusive, but in that case we would 5210 // have had a resolved method before, which triggers the "true" branch above. 5211 break; 5212 case kInterface: 5213 case kVirtual: 5214 case kSuper: 5215 resolved = klass->FindDirectMethod(name, signature); 5216 break; 5217 } 5218 5219 // If we found something, check that it can be accessed by the referrer. 5220 bool exception_generated = false; 5221 if (resolved != nullptr && referrer.Get() != nullptr) { 5222 mirror::Class* methods_class = resolved->GetDeclaringClass(); 5223 mirror::Class* referring_class = referrer->GetDeclaringClass(); 5224 if (!referring_class->CanAccess(methods_class)) { 5225 ThrowIllegalAccessErrorClassForMethodDispatch(referring_class, methods_class, 5226 resolved, type); 5227 exception_generated = true; 5228 } else if (!referring_class->CanAccessMember(methods_class, 5229 resolved->GetAccessFlags())) { 5230 ThrowIllegalAccessErrorMethod(referring_class, resolved); 5231 exception_generated = true; 5232 } 5233 } 5234 if (!exception_generated) { 5235 // Otherwise, throw an IncompatibleClassChangeError if we found something, and check 5236 // interface methods and throw if we find the method there. If we find nothing, throw a 5237 // NoSuchMethodError. 5238 switch (type) { 5239 case kDirect: 5240 case kStatic: 5241 if (resolved != nullptr) { 5242 ThrowIncompatibleClassChangeError(type, kVirtual, resolved, referrer.Get()); 5243 } else { 5244 resolved = klass->FindInterfaceMethod(name, signature); 5245 if (resolved != nullptr) { 5246 ThrowIncompatibleClassChangeError(type, kInterface, resolved, referrer.Get()); 5247 } else { 5248 ThrowNoSuchMethodError(type, klass, name, signature); 5249 } 5250 } 5251 break; 5252 case kInterface: 5253 if (resolved != nullptr) { 5254 ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer.Get()); 5255 } else { 5256 resolved = klass->FindVirtualMethod(name, signature); 5257 if (resolved != nullptr) { 5258 ThrowIncompatibleClassChangeError(type, kVirtual, resolved, referrer.Get()); 5259 } else { 5260 ThrowNoSuchMethodError(type, klass, name, signature); 5261 } 5262 } 5263 break; 5264 case kSuper: 5265 if (resolved != nullptr) { 5266 ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer.Get()); 5267 } else { 5268 ThrowNoSuchMethodError(type, klass, name, signature); 5269 } 5270 break; 5271 case kVirtual: 5272 if (resolved != nullptr) { 5273 ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer.Get()); 5274 } else { 5275 resolved = klass->FindInterfaceMethod(name, signature); 5276 if (resolved != nullptr) { 5277 ThrowIncompatibleClassChangeError(type, kInterface, resolved, referrer.Get()); 5278 } else { 5279 ThrowNoSuchMethodError(type, klass, name, signature); 5280 } 5281 } 5282 break; 5283 } 5284 } 5285 } 5286 Thread::Current()->AssertPendingException(); 5287 return nullptr; 5288 } 5289} 5290 5291ArtField* ClassLinker::ResolveField(const DexFile& dex_file, uint32_t field_idx, 5292 Handle<mirror::DexCache> dex_cache, 5293 Handle<mirror::ClassLoader> class_loader, bool is_static) { 5294 DCHECK(dex_cache.Get() != nullptr); 5295 ArtField* resolved = dex_cache->GetResolvedField(field_idx, image_pointer_size_); 5296 if (resolved != nullptr) { 5297 return resolved; 5298 } 5299 const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx); 5300 Thread* const self = Thread::Current(); 5301 StackHandleScope<1> hs(self); 5302 Handle<mirror::Class> klass( 5303 hs.NewHandle(ResolveType(dex_file, field_id.class_idx_, dex_cache, class_loader))); 5304 if (klass.Get() == nullptr) { 5305 DCHECK(Thread::Current()->IsExceptionPending()); 5306 return nullptr; 5307 } 5308 5309 if (is_static) { 5310 resolved = mirror::Class::FindStaticField(self, klass, dex_cache.Get(), field_idx); 5311 } else { 5312 resolved = klass->FindInstanceField(dex_cache.Get(), field_idx); 5313 } 5314 5315 if (resolved == nullptr) { 5316 const char* name = dex_file.GetFieldName(field_id); 5317 const char* type = dex_file.GetFieldTypeDescriptor(field_id); 5318 if (is_static) { 5319 resolved = mirror::Class::FindStaticField(self, klass, name, type); 5320 } else { 5321 resolved = klass->FindInstanceField(name, type); 5322 } 5323 if (resolved == nullptr) { 5324 ThrowNoSuchFieldError(is_static ? "static " : "instance ", klass.Get(), type, name); 5325 return nullptr; 5326 } 5327 } 5328 dex_cache->SetResolvedField(field_idx, resolved, image_pointer_size_); 5329 return resolved; 5330} 5331 5332ArtField* ClassLinker::ResolveFieldJLS(const DexFile& dex_file, uint32_t field_idx, 5333 Handle<mirror::DexCache> dex_cache, 5334 Handle<mirror::ClassLoader> class_loader) { 5335 DCHECK(dex_cache.Get() != nullptr); 5336 ArtField* resolved = dex_cache->GetResolvedField(field_idx, image_pointer_size_); 5337 if (resolved != nullptr) { 5338 return resolved; 5339 } 5340 const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx); 5341 Thread* self = Thread::Current(); 5342 StackHandleScope<1> hs(self); 5343 Handle<mirror::Class> klass( 5344 hs.NewHandle(ResolveType(dex_file, field_id.class_idx_, dex_cache, class_loader))); 5345 if (klass.Get() == nullptr) { 5346 DCHECK(Thread::Current()->IsExceptionPending()); 5347 return nullptr; 5348 } 5349 5350 StringPiece name(dex_file.StringDataByIdx(field_id.name_idx_)); 5351 StringPiece type(dex_file.StringDataByIdx( 5352 dex_file.GetTypeId(field_id.type_idx_).descriptor_idx_)); 5353 resolved = mirror::Class::FindField(self, klass, name, type); 5354 if (resolved != nullptr) { 5355 dex_cache->SetResolvedField(field_idx, resolved, image_pointer_size_); 5356 } else { 5357 ThrowNoSuchFieldError("", klass.Get(), type, name); 5358 } 5359 return resolved; 5360} 5361 5362const char* ClassLinker::MethodShorty(uint32_t method_idx, mirror::ArtMethod* referrer, 5363 uint32_t* length) { 5364 mirror::Class* declaring_class = referrer->GetDeclaringClass(); 5365 mirror::DexCache* dex_cache = declaring_class->GetDexCache(); 5366 const DexFile& dex_file = *dex_cache->GetDexFile(); 5367 const DexFile::MethodId& method_id = dex_file.GetMethodId(method_idx); 5368 return dex_file.GetMethodShorty(method_id, length); 5369} 5370 5371void ClassLinker::DumpAllClasses(int flags) { 5372 if (dex_cache_image_class_lookup_required_) { 5373 MoveImageClassesToClassTable(); 5374 } 5375 // TODO: at the time this was written, it wasn't safe to call PrettyField with the ClassLinker 5376 // lock held, because it might need to resolve a field's type, which would try to take the lock. 5377 std::vector<mirror::Class*> all_classes; 5378 { 5379 ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 5380 for (GcRoot<mirror::Class>& it : class_table_) { 5381 all_classes.push_back(it.Read()); 5382 } 5383 } 5384 5385 for (size_t i = 0; i < all_classes.size(); ++i) { 5386 all_classes[i]->DumpClass(std::cerr, flags); 5387 } 5388} 5389 5390static OatFile::OatMethod CreateOatMethod(const void* code) { 5391 CHECK(code != nullptr); 5392 const uint8_t* base = reinterpret_cast<const uint8_t*>(code); // Base of data points at code. 5393 base -= sizeof(void*); // Move backward so that code_offset != 0. 5394 const uint32_t code_offset = sizeof(void*); 5395 return OatFile::OatMethod(base, code_offset); 5396} 5397 5398bool ClassLinker::IsQuickResolutionStub(const void* entry_point) const { 5399 return (entry_point == GetQuickResolutionStub()) || 5400 (quick_resolution_trampoline_ == entry_point); 5401} 5402 5403bool ClassLinker::IsQuickToInterpreterBridge(const void* entry_point) const { 5404 return (entry_point == GetQuickToInterpreterBridge()) || 5405 (quick_to_interpreter_bridge_trampoline_ == entry_point); 5406} 5407 5408bool ClassLinker::IsQuickGenericJniStub(const void* entry_point) const { 5409 return (entry_point == GetQuickGenericJniStub()) || 5410 (quick_generic_jni_trampoline_ == entry_point); 5411} 5412 5413const void* ClassLinker::GetRuntimeQuickGenericJniStub() const { 5414 return GetQuickGenericJniStub(); 5415} 5416 5417void ClassLinker::SetEntryPointsToCompiledCode(mirror::ArtMethod* method, 5418 const void* method_code) const { 5419 OatFile::OatMethod oat_method = CreateOatMethod(method_code); 5420 oat_method.LinkMethod(method); 5421 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 5422} 5423 5424void ClassLinker::SetEntryPointsToInterpreter(mirror::ArtMethod* method) const { 5425 if (!method->IsNative()) { 5426 method->SetEntryPointFromInterpreter(artInterpreterToInterpreterBridge); 5427 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge()); 5428 } else { 5429 const void* quick_method_code = GetQuickGenericJniStub(); 5430 OatFile::OatMethod oat_method = CreateOatMethod(quick_method_code); 5431 oat_method.LinkMethod(method); 5432 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 5433 } 5434} 5435 5436void ClassLinker::DumpForSigQuit(std::ostream& os) { 5437 Thread* self = Thread::Current(); 5438 if (dex_cache_image_class_lookup_required_) { 5439 ScopedObjectAccess soa(self); 5440 MoveImageClassesToClassTable(); 5441 } 5442 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 5443 os << "Zygote loaded classes=" << pre_zygote_class_table_.Size() << " post zygote classes=" 5444 << class_table_.Size() << "\n"; 5445} 5446 5447size_t ClassLinker::NumLoadedClasses() { 5448 if (dex_cache_image_class_lookup_required_) { 5449 MoveImageClassesToClassTable(); 5450 } 5451 ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 5452 // Only return non zygote classes since these are the ones which apps which care about. 5453 return class_table_.Size(); 5454} 5455 5456pid_t ClassLinker::GetClassesLockOwner() { 5457 return Locks::classlinker_classes_lock_->GetExclusiveOwnerTid(); 5458} 5459 5460pid_t ClassLinker::GetDexLockOwner() { 5461 return dex_lock_.GetExclusiveOwnerTid(); 5462} 5463 5464void ClassLinker::SetClassRoot(ClassRoot class_root, mirror::Class* klass) { 5465 DCHECK(!init_done_); 5466 5467 DCHECK(klass != nullptr); 5468 DCHECK(klass->GetClassLoader() == nullptr); 5469 5470 mirror::ObjectArray<mirror::Class>* class_roots = class_roots_.Read(); 5471 DCHECK(class_roots != nullptr); 5472 DCHECK(class_roots->Get(class_root) == nullptr); 5473 class_roots->Set<false>(class_root, klass); 5474} 5475 5476const char* ClassLinker::GetClassRootDescriptor(ClassRoot class_root) { 5477 static const char* class_roots_descriptors[] = { 5478 "Ljava/lang/Class;", 5479 "Ljava/lang/Object;", 5480 "[Ljava/lang/Class;", 5481 "[Ljava/lang/Object;", 5482 "Ljava/lang/String;", 5483 "Ljava/lang/DexCache;", 5484 "Ljava/lang/ref/Reference;", 5485 "Ljava/lang/reflect/ArtMethod;", 5486 "Ljava/lang/reflect/Constructor;", 5487 "Ljava/lang/reflect/Field;", 5488 "Ljava/lang/reflect/Method;", 5489 "Ljava/lang/reflect/Proxy;", 5490 "[Ljava/lang/String;", 5491 "[Ljava/lang/reflect/ArtMethod;", 5492 "[Ljava/lang/reflect/Constructor;", 5493 "[Ljava/lang/reflect/Field;", 5494 "[Ljava/lang/reflect/Method;", 5495 "Ljava/lang/ClassLoader;", 5496 "Ljava/lang/Throwable;", 5497 "Ljava/lang/ClassNotFoundException;", 5498 "Ljava/lang/StackTraceElement;", 5499 "Z", 5500 "B", 5501 "C", 5502 "D", 5503 "F", 5504 "I", 5505 "J", 5506 "S", 5507 "V", 5508 "[Z", 5509 "[B", 5510 "[C", 5511 "[D", 5512 "[F", 5513 "[I", 5514 "[J", 5515 "[S", 5516 "[Ljava/lang/StackTraceElement;", 5517 }; 5518 static_assert(arraysize(class_roots_descriptors) == size_t(kClassRootsMax), 5519 "Mismatch between class descriptors and class-root enum"); 5520 5521 const char* descriptor = class_roots_descriptors[class_root]; 5522 CHECK(descriptor != nullptr); 5523 return descriptor; 5524} 5525 5526std::size_t ClassLinker::ClassDescriptorHashEquals::operator()(const GcRoot<mirror::Class>& root) 5527 const { 5528 std::string temp; 5529 return ComputeModifiedUtf8Hash(root.Read()->GetDescriptor(&temp)); 5530} 5531 5532bool ClassLinker::ClassDescriptorHashEquals::operator()(const GcRoot<mirror::Class>& a, 5533 const GcRoot<mirror::Class>& b) const { 5534 if (a.Read()->GetClassLoader() != b.Read()->GetClassLoader()) { 5535 return false; 5536 } 5537 std::string temp; 5538 return a.Read()->DescriptorEquals(b.Read()->GetDescriptor(&temp)); 5539} 5540 5541std::size_t ClassLinker::ClassDescriptorHashEquals::operator()( 5542 const std::pair<const char*, mirror::ClassLoader*>& element) const { 5543 return ComputeModifiedUtf8Hash(element.first); 5544} 5545 5546bool ClassLinker::ClassDescriptorHashEquals::operator()( 5547 const GcRoot<mirror::Class>& a, const std::pair<const char*, mirror::ClassLoader*>& b) const { 5548 if (a.Read()->GetClassLoader() != b.second) { 5549 return false; 5550 } 5551 return a.Read()->DescriptorEquals(b.first); 5552} 5553 5554bool ClassLinker::ClassDescriptorHashEquals::operator()(const GcRoot<mirror::Class>& a, 5555 const char* descriptor) const { 5556 return a.Read()->DescriptorEquals(descriptor); 5557} 5558 5559std::size_t ClassLinker::ClassDescriptorHashEquals::operator()(const char* descriptor) const { 5560 return ComputeModifiedUtf8Hash(descriptor); 5561} 5562 5563bool ClassLinker::MayBeCalledWithDirectCodePointer(mirror::ArtMethod* m) { 5564 if (Runtime::Current()->UseJit()) { 5565 // JIT can have direct code pointers from any method to any other method. 5566 return true; 5567 } 5568 // Non-image methods don't use direct code pointer. 5569 if (!m->GetDeclaringClass()->IsBootStrapClassLoaded()) { 5570 return false; 5571 } 5572 if (m->IsPrivate()) { 5573 // The method can only be called inside its own oat file. Therefore it won't be called using 5574 // its direct code if the oat file has been compiled in PIC mode. 5575 const DexFile& dex_file = m->GetDeclaringClass()->GetDexFile(); 5576 const OatFile::OatDexFile* oat_dex_file = dex_file.GetOatDexFile(); 5577 if (oat_dex_file == nullptr) { 5578 // No oat file: the method has not been compiled. 5579 return false; 5580 } 5581 const OatFile* oat_file = oat_dex_file->GetOatFile(); 5582 return oat_file != nullptr && !oat_file->IsPic(); 5583 } else { 5584 // The method can be called outside its own oat file. Therefore it won't be called using its 5585 // direct code pointer only if all loaded oat files have been compiled in PIC mode. 5586 ReaderMutexLock mu(Thread::Current(), dex_lock_); 5587 for (const OatFile* oat_file : oat_files_) { 5588 if (!oat_file->IsPic()) { 5589 return true; 5590 } 5591 } 5592 return false; 5593 } 5594} 5595 5596jobject ClassLinker::CreatePathClassLoader(Thread* self, std::vector<const DexFile*>& dex_files) { 5597 // SOAAlreadyRunnable is protected, and we need something to add a global reference. 5598 // We could move the jobject to the callers, but all call-sites do this... 5599 ScopedObjectAccessUnchecked soa(self); 5600 5601 // Register the dex files. 5602 for (const DexFile* dex_file : dex_files) { 5603 RegisterDexFile(*dex_file); 5604 } 5605 5606 // For now, create a libcore-level DexFile for each ART DexFile. This "explodes" multidex. 5607 StackHandleScope<10> hs(self); 5608 5609 ArtField* dex_elements_field = 5610 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList_dexElements); 5611 5612 mirror::Class* dex_elements_class = dex_elements_field->GetType<true>(); 5613 DCHECK(dex_elements_class != nullptr); 5614 DCHECK(dex_elements_class->IsArrayClass()); 5615 Handle<mirror::ObjectArray<mirror::Object>> h_dex_elements(hs.NewHandle( 5616 mirror::ObjectArray<mirror::Object>::Alloc(self, dex_elements_class, dex_files.size()))); 5617 Handle<mirror::Class> h_dex_element_class = 5618 hs.NewHandle(dex_elements_class->GetComponentType()); 5619 5620 ArtField* element_file_field = 5621 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList__Element_dexFile); 5622 DCHECK_EQ(h_dex_element_class.Get(), element_file_field->GetDeclaringClass()); 5623 5624 ArtField* cookie_field = soa.DecodeField(WellKnownClasses::dalvik_system_DexFile_cookie); 5625 DCHECK_EQ(cookie_field->GetDeclaringClass(), element_file_field->GetType<false>()); 5626 5627 // Fill the elements array. 5628 int32_t index = 0; 5629 for (const DexFile* dex_file : dex_files) { 5630 StackHandleScope<3> hs2(self); 5631 5632 Handle<mirror::LongArray> h_long_array = hs2.NewHandle(mirror::LongArray::Alloc(self, 1)); 5633 DCHECK(h_long_array.Get() != nullptr); 5634 h_long_array->Set(0, reinterpret_cast<intptr_t>(dex_file)); 5635 5636 Handle<mirror::Object> h_dex_file = hs2.NewHandle( 5637 cookie_field->GetDeclaringClass()->AllocObject(self)); 5638 DCHECK(h_dex_file.Get() != nullptr); 5639 cookie_field->SetObject<false>(h_dex_file.Get(), h_long_array.Get()); 5640 5641 Handle<mirror::Object> h_element = hs2.NewHandle(h_dex_element_class->AllocObject(self)); 5642 DCHECK(h_element.Get() != nullptr); 5643 element_file_field->SetObject<false>(h_element.Get(), h_dex_file.Get()); 5644 5645 h_dex_elements->Set(index, h_element.Get()); 5646 index++; 5647 } 5648 DCHECK_EQ(index, h_dex_elements->GetLength()); 5649 5650 // Create DexPathList. 5651 Handle<mirror::Object> h_dex_path_list = hs.NewHandle( 5652 dex_elements_field->GetDeclaringClass()->AllocObject(self)); 5653 DCHECK(h_dex_path_list.Get() != nullptr); 5654 // Set elements. 5655 dex_elements_field->SetObject<false>(h_dex_path_list.Get(), h_dex_elements.Get()); 5656 5657 // Create PathClassLoader. 5658 Handle<mirror::Class> h_path_class_class = hs.NewHandle( 5659 soa.Decode<mirror::Class*>(WellKnownClasses::dalvik_system_PathClassLoader)); 5660 Handle<mirror::Object> h_path_class_loader = hs.NewHandle( 5661 h_path_class_class->AllocObject(self)); 5662 DCHECK(h_path_class_loader.Get() != nullptr); 5663 // Set DexPathList. 5664 ArtField* path_list_field = 5665 soa.DecodeField(WellKnownClasses::dalvik_system_PathClassLoader_pathList); 5666 DCHECK(path_list_field != nullptr); 5667 path_list_field->SetObject<false>(h_path_class_loader.Get(), h_dex_path_list.Get()); 5668 5669 // Make a pretend boot-classpath. 5670 // TODO: Should we scan the image? 5671 ArtField* const parent_field = 5672 mirror::Class::FindField(self, hs.NewHandle(h_path_class_loader->GetClass()), "parent", 5673 "Ljava/lang/ClassLoader;"); 5674 DCHECK(parent_field!= nullptr); 5675 mirror::Object* boot_cl = 5676 soa.Decode<mirror::Class*>(WellKnownClasses::java_lang_BootClassLoader)->AllocObject(self); 5677 parent_field->SetObject<false>(h_path_class_loader.Get(), boot_cl); 5678 5679 // Make it a global ref and return. 5680 ScopedLocalRef<jobject> local_ref( 5681 soa.Env(), soa.Env()->AddLocalReference<jobject>(h_path_class_loader.Get())); 5682 return soa.Env()->NewGlobalRef(local_ref.get()); 5683} 5684 5685} // namespace art 5686