class_linker.cc revision 0cba004b97245300d7f39318d5921ee8edbef1ac
1/* 2 * Copyright (C) 2011 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#include "class_linker.h" 18 19#include <deque> 20#include <iostream> 21#include <memory> 22#include <queue> 23#include <string> 24#include <unistd.h> 25#include <utility> 26#include <vector> 27 28#include "art_field-inl.h" 29#include "base/casts.h" 30#include "base/logging.h" 31#include "base/scoped_flock.h" 32#include "base/stl_util.h" 33#include "base/unix_file/fd_file.h" 34#include "base/value_object.h" 35#include "class_linker-inl.h" 36#include "compiler_callbacks.h" 37#include "debugger.h" 38#include "dex_file-inl.h" 39#include "entrypoints/runtime_asm_entrypoints.h" 40#include "gc_root-inl.h" 41#include "gc/accounting/card_table-inl.h" 42#include "gc/accounting/heap_bitmap.h" 43#include "gc/heap.h" 44#include "gc/space/image_space.h" 45#include "handle_scope.h" 46#include "intern_table.h" 47#include "interpreter/interpreter.h" 48#include "jit/jit.h" 49#include "jit/jit_code_cache.h" 50#include "leb128.h" 51#include "linear_alloc.h" 52#include "oat.h" 53#include "oat_file.h" 54#include "oat_file_assistant.h" 55#include "object_lock.h" 56#include "mirror/art_method-inl.h" 57#include "mirror/class.h" 58#include "mirror/class-inl.h" 59#include "mirror/class_loader.h" 60#include "mirror/dex_cache-inl.h" 61#include "mirror/field.h" 62#include "mirror/iftable-inl.h" 63#include "mirror/method.h" 64#include "mirror/object-inl.h" 65#include "mirror/object_array-inl.h" 66#include "mirror/proxy.h" 67#include "mirror/reference-inl.h" 68#include "mirror/stack_trace_element.h" 69#include "mirror/string-inl.h" 70#include "os.h" 71#include "runtime.h" 72#include "entrypoints/entrypoint_utils.h" 73#include "ScopedLocalRef.h" 74#include "scoped_thread_state_change.h" 75#include "handle_scope-inl.h" 76#include "thread-inl.h" 77#include "utils.h" 78#include "verifier/method_verifier.h" 79#include "well_known_classes.h" 80 81namespace art { 82 83static constexpr bool kSanityCheckObjects = kIsDebugBuild; 84 85static void ThrowNoClassDefFoundError(const char* fmt, ...) 86 __attribute__((__format__(__printf__, 1, 2))) 87 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 88static void ThrowNoClassDefFoundError(const char* fmt, ...) { 89 va_list args; 90 va_start(args, fmt); 91 Thread* self = Thread::Current(); 92 self->ThrowNewExceptionV("Ljava/lang/NoClassDefFoundError;", fmt, args); 93 va_end(args); 94} 95 96static bool HasInitWithString(Thread* self, ClassLinker* class_linker, const char* descriptor) 97 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 98 mirror::ArtMethod* method = self->GetCurrentMethod(nullptr); 99 StackHandleScope<1> hs(self); 100 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(method != nullptr ? 101 method->GetDeclaringClass()->GetClassLoader() 102 : nullptr)); 103 mirror::Class* exception_class = class_linker->FindClass(self, descriptor, class_loader); 104 105 if (exception_class == nullptr) { 106 // No exc class ~ no <init>-with-string. 107 CHECK(self->IsExceptionPending()); 108 self->ClearException(); 109 return false; 110 } 111 112 mirror::ArtMethod* exception_init_method = 113 exception_class->FindDeclaredDirectMethod("<init>", "(Ljava/lang/String;)V"); 114 return exception_init_method != nullptr; 115} 116 117void ClassLinker::ThrowEarlierClassFailure(mirror::Class* c) { 118 // The class failed to initialize on a previous attempt, so we want to throw 119 // a NoClassDefFoundError (v2 2.17.5). The exception to this rule is if we 120 // failed in verification, in which case v2 5.4.1 says we need to re-throw 121 // the previous error. 122 Runtime* const runtime = Runtime::Current(); 123 if (!runtime->IsAotCompiler()) { // Give info if this occurs at runtime. 124 LOG(INFO) << "Rejecting re-init on previously-failed class " << PrettyClass(c); 125 } 126 127 CHECK(c->IsErroneous()) << PrettyClass(c) << " " << c->GetStatus(); 128 Thread* self = Thread::Current(); 129 if (runtime->IsAotCompiler()) { 130 // At compile time, accurate errors and NCDFE are disabled to speed compilation. 131 mirror::Throwable* pre_allocated = runtime->GetPreAllocatedNoClassDefFoundError(); 132 self->SetException(pre_allocated); 133 } else { 134 if (c->GetVerifyErrorClass() != nullptr) { 135 // TODO: change the verifier to store an _instance_, with a useful detail message? 136 // It's possible the exception doesn't have a <init>(String). 137 std::string temp; 138 const char* descriptor = c->GetVerifyErrorClass()->GetDescriptor(&temp); 139 140 if (HasInitWithString(self, this, descriptor)) { 141 self->ThrowNewException(descriptor, PrettyDescriptor(c).c_str()); 142 } else { 143 self->ThrowNewException(descriptor, nullptr); 144 } 145 } else { 146 self->ThrowNewException("Ljava/lang/NoClassDefFoundError;", 147 PrettyDescriptor(c).c_str()); 148 } 149 } 150} 151 152static void VlogClassInitializationFailure(Handle<mirror::Class> klass) 153 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 154 if (VLOG_IS_ON(class_linker)) { 155 std::string temp; 156 LOG(INFO) << "Failed to initialize class " << klass->GetDescriptor(&temp) << " from " 157 << klass->GetLocation() << "\n" << Thread::Current()->GetException()->Dump(); 158 } 159} 160 161static void WrapExceptionInInitializer(Handle<mirror::Class> klass) 162 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 163 Thread* self = Thread::Current(); 164 JNIEnv* env = self->GetJniEnv(); 165 166 ScopedLocalRef<jthrowable> cause(env, env->ExceptionOccurred()); 167 CHECK(cause.get() != nullptr); 168 169 env->ExceptionClear(); 170 bool is_error = env->IsInstanceOf(cause.get(), WellKnownClasses::java_lang_Error); 171 env->Throw(cause.get()); 172 173 // We only wrap non-Error exceptions; an Error can just be used as-is. 174 if (!is_error) { 175 self->ThrowNewWrappedException("Ljava/lang/ExceptionInInitializerError;", nullptr); 176 } 177 VlogClassInitializationFailure(klass); 178} 179 180// Gap between two fields in object layout. 181struct FieldGap { 182 uint32_t start_offset; // The offset from the start of the object. 183 uint32_t size; // The gap size of 1, 2, or 4 bytes. 184}; 185struct FieldGapsComparator { 186 explicit FieldGapsComparator() { 187 } 188 bool operator() (const FieldGap& lhs, const FieldGap& rhs) 189 NO_THREAD_SAFETY_ANALYSIS { 190 // Sort by gap size, largest first. Secondary sort by starting offset. 191 return lhs.size > rhs.size || (lhs.size == rhs.size && lhs.start_offset < rhs.start_offset); 192 } 193}; 194typedef std::priority_queue<FieldGap, std::vector<FieldGap>, FieldGapsComparator> FieldGaps; 195 196// Adds largest aligned gaps to queue of gaps. 197static void AddFieldGap(uint32_t gap_start, uint32_t gap_end, FieldGaps* gaps) { 198 DCHECK(gaps != nullptr); 199 200 uint32_t current_offset = gap_start; 201 while (current_offset != gap_end) { 202 size_t remaining = gap_end - current_offset; 203 if (remaining >= sizeof(uint32_t) && IsAligned<4>(current_offset)) { 204 gaps->push(FieldGap {current_offset, sizeof(uint32_t)}); 205 current_offset += sizeof(uint32_t); 206 } else if (remaining >= sizeof(uint16_t) && IsAligned<2>(current_offset)) { 207 gaps->push(FieldGap {current_offset, sizeof(uint16_t)}); 208 current_offset += sizeof(uint16_t); 209 } else { 210 gaps->push(FieldGap {current_offset, sizeof(uint8_t)}); 211 current_offset += sizeof(uint8_t); 212 } 213 DCHECK_LE(current_offset, gap_end) << "Overran gap"; 214 } 215} 216// Shuffle fields forward, making use of gaps whenever possible. 217template<int n> 218static void ShuffleForward(size_t* current_field_idx, 219 MemberOffset* field_offset, 220 std::deque<ArtField*>* grouped_and_sorted_fields, 221 FieldGaps* gaps) 222 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 223 DCHECK(current_field_idx != nullptr); 224 DCHECK(grouped_and_sorted_fields != nullptr); 225 DCHECK(gaps != nullptr); 226 DCHECK(field_offset != nullptr); 227 228 DCHECK(IsPowerOfTwo(n)); 229 while (!grouped_and_sorted_fields->empty()) { 230 ArtField* field = grouped_and_sorted_fields->front(); 231 Primitive::Type type = field->GetTypeAsPrimitiveType(); 232 if (Primitive::ComponentSize(type) < n) { 233 break; 234 } 235 if (!IsAligned<n>(field_offset->Uint32Value())) { 236 MemberOffset old_offset = *field_offset; 237 *field_offset = MemberOffset(RoundUp(field_offset->Uint32Value(), n)); 238 AddFieldGap(old_offset.Uint32Value(), field_offset->Uint32Value(), gaps); 239 } 240 CHECK(type != Primitive::kPrimNot) << PrettyField(field); // should be primitive types 241 grouped_and_sorted_fields->pop_front(); 242 if (!gaps->empty() && gaps->top().size >= n) { 243 FieldGap gap = gaps->top(); 244 gaps->pop(); 245 DCHECK(IsAligned<n>(gap.start_offset)); 246 field->SetOffset(MemberOffset(gap.start_offset)); 247 if (gap.size > n) { 248 AddFieldGap(gap.start_offset + n, gap.start_offset + gap.size, gaps); 249 } 250 } else { 251 DCHECK(IsAligned<n>(field_offset->Uint32Value())); 252 field->SetOffset(*field_offset); 253 *field_offset = MemberOffset(field_offset->Uint32Value() + n); 254 } 255 ++(*current_field_idx); 256 } 257} 258 259ClassLinker::ClassLinker(InternTable* intern_table) 260 // dex_lock_ is recursive as it may be used in stack dumping. 261 : dex_lock_("ClassLinker dex lock", kDefaultMutexLevel), 262 dex_cache_image_class_lookup_required_(false), 263 failed_dex_cache_class_lookups_(0), 264 class_roots_(nullptr), 265 array_iftable_(nullptr), 266 find_array_class_cache_next_victim_(0), 267 init_done_(false), 268 log_new_dex_caches_roots_(false), 269 log_new_class_table_roots_(false), 270 intern_table_(intern_table), 271 quick_resolution_trampoline_(nullptr), 272 quick_imt_conflict_trampoline_(nullptr), 273 quick_generic_jni_trampoline_(nullptr), 274 quick_to_interpreter_bridge_trampoline_(nullptr), 275 image_pointer_size_(sizeof(void*)) { 276 CHECK(intern_table_ != nullptr); 277 for (size_t i = 0; i < kFindArrayCacheSize; ++i) { 278 find_array_class_cache_[i] = GcRoot<mirror::Class>(nullptr); 279 } 280} 281 282void ClassLinker::InitWithoutImage(std::vector<std::unique_ptr<const DexFile>> boot_class_path) { 283 VLOG(startup) << "ClassLinker::Init"; 284 CHECK(!Runtime::Current()->GetHeap()->HasImageSpace()) << "Runtime has image. We should use it."; 285 286 CHECK(!init_done_); 287 288 // java_lang_Class comes first, it's needed for AllocClass 289 Thread* const self = Thread::Current(); 290 gc::Heap* const heap = Runtime::Current()->GetHeap(); 291 // The GC can't handle an object with a null class since we can't get the size of this object. 292 heap->IncrementDisableMovingGC(self); 293 StackHandleScope<64> hs(self); // 64 is picked arbitrarily. 294 Handle<mirror::Class> java_lang_Class(hs.NewHandle(down_cast<mirror::Class*>( 295 heap->AllocNonMovableObject<true>(self, nullptr, 296 mirror::Class::ClassClassSize(), 297 VoidFunctor())))); 298 CHECK(java_lang_Class.Get() != nullptr); 299 mirror::Class::SetClassClass(java_lang_Class.Get()); 300 java_lang_Class->SetClass(java_lang_Class.Get()); 301 if (kUseBakerOrBrooksReadBarrier) { 302 java_lang_Class->AssertReadBarrierPointer(); 303 } 304 java_lang_Class->SetClassSize(mirror::Class::ClassClassSize()); 305 java_lang_Class->SetPrimitiveType(Primitive::kPrimNot); 306 heap->DecrementDisableMovingGC(self); 307 // AllocClass(mirror::Class*) can now be used 308 309 // Class[] is used for reflection support. 310 Handle<mirror::Class> class_array_class(hs.NewHandle( 311 AllocClass(self, java_lang_Class.Get(), mirror::ObjectArray<mirror::Class>::ClassSize()))); 312 class_array_class->SetComponentType(java_lang_Class.Get()); 313 314 // java_lang_Object comes next so that object_array_class can be created. 315 Handle<mirror::Class> java_lang_Object(hs.NewHandle( 316 AllocClass(self, java_lang_Class.Get(), mirror::Object::ClassSize()))); 317 CHECK(java_lang_Object.Get() != nullptr); 318 // backfill Object as the super class of Class. 319 java_lang_Class->SetSuperClass(java_lang_Object.Get()); 320 mirror::Class::SetStatus(java_lang_Object, mirror::Class::kStatusLoaded, self); 321 322 // Object[] next to hold class roots. 323 Handle<mirror::Class> object_array_class(hs.NewHandle( 324 AllocClass(self, java_lang_Class.Get(), mirror::ObjectArray<mirror::Object>::ClassSize()))); 325 object_array_class->SetComponentType(java_lang_Object.Get()); 326 327 // Setup the char (primitive) class to be used for char[]. 328 Handle<mirror::Class> char_class(hs.NewHandle( 329 AllocClass(self, java_lang_Class.Get(), mirror::Class::PrimitiveClassSize()))); 330 // The primitive char class won't be initialized by 331 // InitializePrimitiveClass until line 459, but strings (and 332 // internal char arrays) will be allocated before that and the 333 // component size, which is computed from the primitive type, needs 334 // to be set here. 335 char_class->SetPrimitiveType(Primitive::kPrimChar); 336 337 // Setup the char[] class to be used for String. 338 Handle<mirror::Class> char_array_class(hs.NewHandle( 339 AllocClass(self, java_lang_Class.Get(), 340 mirror::Array::ClassSize()))); 341 char_array_class->SetComponentType(char_class.Get()); 342 mirror::CharArray::SetArrayClass(char_array_class.Get()); 343 344 // Setup String. 345 Handle<mirror::Class> java_lang_String(hs.NewHandle( 346 AllocClass(self, java_lang_Class.Get(), mirror::String::ClassSize()))); 347 mirror::String::SetClass(java_lang_String.Get()); 348 mirror::Class::SetStatus(java_lang_String, mirror::Class::kStatusResolved, self); 349 java_lang_String->SetStringClass(); 350 351 // Setup java.lang.ref.Reference. 352 Handle<mirror::Class> java_lang_ref_Reference(hs.NewHandle( 353 AllocClass(self, java_lang_Class.Get(), mirror::Reference::ClassSize()))); 354 mirror::Reference::SetClass(java_lang_ref_Reference.Get()); 355 java_lang_ref_Reference->SetObjectSize(mirror::Reference::InstanceSize()); 356 mirror::Class::SetStatus(java_lang_ref_Reference, mirror::Class::kStatusResolved, self); 357 358 // Create storage for root classes, save away our work so far (requires descriptors). 359 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class>>( 360 mirror::ObjectArray<mirror::Class>::Alloc(self, object_array_class.Get(), 361 kClassRootsMax)); 362 CHECK(!class_roots_.IsNull()); 363 SetClassRoot(kJavaLangClass, java_lang_Class.Get()); 364 SetClassRoot(kJavaLangObject, java_lang_Object.Get()); 365 SetClassRoot(kClassArrayClass, class_array_class.Get()); 366 SetClassRoot(kObjectArrayClass, object_array_class.Get()); 367 SetClassRoot(kCharArrayClass, char_array_class.Get()); 368 SetClassRoot(kJavaLangString, java_lang_String.Get()); 369 SetClassRoot(kJavaLangRefReference, java_lang_ref_Reference.Get()); 370 371 // Setup the primitive type classes. 372 SetClassRoot(kPrimitiveBoolean, CreatePrimitiveClass(self, Primitive::kPrimBoolean)); 373 SetClassRoot(kPrimitiveByte, CreatePrimitiveClass(self, Primitive::kPrimByte)); 374 SetClassRoot(kPrimitiveShort, CreatePrimitiveClass(self, Primitive::kPrimShort)); 375 SetClassRoot(kPrimitiveInt, CreatePrimitiveClass(self, Primitive::kPrimInt)); 376 SetClassRoot(kPrimitiveLong, CreatePrimitiveClass(self, Primitive::kPrimLong)); 377 SetClassRoot(kPrimitiveFloat, CreatePrimitiveClass(self, Primitive::kPrimFloat)); 378 SetClassRoot(kPrimitiveDouble, CreatePrimitiveClass(self, Primitive::kPrimDouble)); 379 SetClassRoot(kPrimitiveVoid, CreatePrimitiveClass(self, Primitive::kPrimVoid)); 380 381 // Create array interface entries to populate once we can load system classes. 382 array_iftable_ = GcRoot<mirror::IfTable>(AllocIfTable(self, 2)); 383 384 // Create int array type for AllocDexCache (done in AppendToBootClassPath). 385 Handle<mirror::Class> int_array_class(hs.NewHandle( 386 AllocClass(self, java_lang_Class.Get(), mirror::Array::ClassSize()))); 387 int_array_class->SetComponentType(GetClassRoot(kPrimitiveInt)); 388 mirror::IntArray::SetArrayClass(int_array_class.Get()); 389 SetClassRoot(kIntArrayClass, int_array_class.Get()); 390 391 // Create long array type for AllocDexCache (done in AppendToBootClassPath). 392 Handle<mirror::Class> long_array_class(hs.NewHandle( 393 AllocClass(self, java_lang_Class.Get(), mirror::Array::ClassSize()))); 394 long_array_class->SetComponentType(GetClassRoot(kPrimitiveLong)); 395 mirror::LongArray::SetArrayClass(long_array_class.Get()); 396 SetClassRoot(kLongArrayClass, long_array_class.Get()); 397 398 // now that these are registered, we can use AllocClass() and AllocObjectArray 399 400 // Set up DexCache. This cannot be done later since AppendToBootClassPath calls AllocDexCache. 401 Handle<mirror::Class> java_lang_DexCache(hs.NewHandle( 402 AllocClass(self, java_lang_Class.Get(), mirror::DexCache::ClassSize()))); 403 SetClassRoot(kJavaLangDexCache, java_lang_DexCache.Get()); 404 java_lang_DexCache->SetObjectSize(mirror::DexCache::InstanceSize()); 405 mirror::Class::SetStatus(java_lang_DexCache, mirror::Class::kStatusResolved, self); 406 407 // Constructor, Method, and AbstractMethod are necessary so 408 // that FindClass can link members. 409 410 Handle<mirror::Class> java_lang_reflect_ArtMethod(hs.NewHandle( 411 AllocClass(self, java_lang_Class.Get(), mirror::ArtMethod::ClassSize()))); 412 CHECK(java_lang_reflect_ArtMethod.Get() != nullptr); 413 size_t pointer_size = GetInstructionSetPointerSize(Runtime::Current()->GetInstructionSet()); 414 java_lang_reflect_ArtMethod->SetObjectSize(mirror::ArtMethod::InstanceSize(pointer_size)); 415 SetClassRoot(kJavaLangReflectArtMethod, java_lang_reflect_ArtMethod.Get()); 416 mirror::Class::SetStatus(java_lang_reflect_ArtMethod, mirror::Class::kStatusResolved, self); 417 mirror::ArtMethod::SetClass(java_lang_reflect_ArtMethod.Get()); 418 419 // Set up array classes for string, field, method 420 Handle<mirror::Class> object_array_string(hs.NewHandle( 421 AllocClass(self, java_lang_Class.Get(), 422 mirror::ObjectArray<mirror::String>::ClassSize()))); 423 object_array_string->SetComponentType(java_lang_String.Get()); 424 SetClassRoot(kJavaLangStringArrayClass, object_array_string.Get()); 425 426 Handle<mirror::Class> object_array_art_method(hs.NewHandle( 427 AllocClass(self, java_lang_Class.Get(), 428 mirror::ObjectArray<mirror::ArtMethod>::ClassSize()))); 429 object_array_art_method->SetComponentType(java_lang_reflect_ArtMethod.Get()); 430 SetClassRoot(kJavaLangReflectArtMethodArrayClass, object_array_art_method.Get()); 431 432 // Setup boot_class_path_ and register class_path now that we can use AllocObjectArray to create 433 // DexCache instances. Needs to be after String, Field, Method arrays since AllocDexCache uses 434 // these roots. 435 CHECK_NE(0U, boot_class_path.size()); 436 for (auto& dex_file : boot_class_path) { 437 CHECK(dex_file.get() != nullptr); 438 AppendToBootClassPath(self, *dex_file); 439 opened_dex_files_.push_back(std::move(dex_file)); 440 } 441 442 // now we can use FindSystemClass 443 444 // run char class through InitializePrimitiveClass to finish init 445 InitializePrimitiveClass(char_class.Get(), Primitive::kPrimChar); 446 SetClassRoot(kPrimitiveChar, char_class.Get()); // needs descriptor 447 448 // Create runtime resolution and imt conflict methods. Also setup the default imt. 449 Runtime* runtime = Runtime::Current(); 450 runtime->SetResolutionMethod(runtime->CreateResolutionMethod()); 451 runtime->SetImtConflictMethod(runtime->CreateImtConflictMethod()); 452 runtime->SetImtUnimplementedMethod(runtime->CreateImtConflictMethod()); 453 runtime->SetDefaultImt(runtime->CreateDefaultImt(this)); 454 455 // Set up GenericJNI entrypoint. That is mainly a hack for common_compiler_test.h so that 456 // we do not need friend classes or a publicly exposed setter. 457 quick_generic_jni_trampoline_ = GetQuickGenericJniStub(); 458 if (!runtime->IsAotCompiler()) { 459 // We need to set up the generic trampolines since we don't have an image. 460 quick_resolution_trampoline_ = GetQuickResolutionStub(); 461 quick_imt_conflict_trampoline_ = GetQuickImtConflictStub(); 462 quick_to_interpreter_bridge_trampoline_ = GetQuickToInterpreterBridge(); 463 } 464 465 // Object, String and DexCache need to be rerun through FindSystemClass to finish init 466 mirror::Class::SetStatus(java_lang_Object, mirror::Class::kStatusNotReady, self); 467 CHECK_EQ(java_lang_Object.Get(), FindSystemClass(self, "Ljava/lang/Object;")); 468 CHECK_EQ(java_lang_Object->GetObjectSize(), mirror::Object::InstanceSize()); 469 mirror::Class::SetStatus(java_lang_String, mirror::Class::kStatusNotReady, self); 470 mirror::Class* String_class = FindSystemClass(self, "Ljava/lang/String;"); 471 if (java_lang_String.Get() != String_class) { 472 std::ostringstream os1, os2; 473 java_lang_String->DumpClass(os1, mirror::Class::kDumpClassFullDetail); 474 String_class->DumpClass(os2, mirror::Class::kDumpClassFullDetail); 475 LOG(FATAL) << os1.str() << "\n\n" << os2.str(); 476 } 477 mirror::Class::SetStatus(java_lang_DexCache, mirror::Class::kStatusNotReady, self); 478 CHECK_EQ(java_lang_DexCache.Get(), FindSystemClass(self, "Ljava/lang/DexCache;")); 479 CHECK_EQ(java_lang_DexCache->GetObjectSize(), mirror::DexCache::InstanceSize()); 480 481 // Setup the primitive array type classes - can't be done until Object has a vtable. 482 SetClassRoot(kBooleanArrayClass, FindSystemClass(self, "[Z")); 483 mirror::BooleanArray::SetArrayClass(GetClassRoot(kBooleanArrayClass)); 484 485 SetClassRoot(kByteArrayClass, FindSystemClass(self, "[B")); 486 mirror::ByteArray::SetArrayClass(GetClassRoot(kByteArrayClass)); 487 488 CHECK_EQ(char_array_class.Get(), FindSystemClass(self, "[C")); 489 490 SetClassRoot(kShortArrayClass, FindSystemClass(self, "[S")); 491 mirror::ShortArray::SetArrayClass(GetClassRoot(kShortArrayClass)); 492 493 CHECK_EQ(int_array_class.Get(), FindSystemClass(self, "[I")); 494 495 CHECK_EQ(long_array_class.Get(), FindSystemClass(self, "[J")); 496 497 SetClassRoot(kFloatArrayClass, FindSystemClass(self, "[F")); 498 mirror::FloatArray::SetArrayClass(GetClassRoot(kFloatArrayClass)); 499 500 SetClassRoot(kDoubleArrayClass, FindSystemClass(self, "[D")); 501 mirror::DoubleArray::SetArrayClass(GetClassRoot(kDoubleArrayClass)); 502 503 CHECK_EQ(class_array_class.Get(), FindSystemClass(self, "[Ljava/lang/Class;")); 504 505 CHECK_EQ(object_array_class.Get(), FindSystemClass(self, "[Ljava/lang/Object;")); 506 507 // Setup the single, global copy of "iftable". 508 auto java_lang_Cloneable = hs.NewHandle(FindSystemClass(self, "Ljava/lang/Cloneable;")); 509 CHECK(java_lang_Cloneable.Get() != nullptr); 510 auto java_io_Serializable = hs.NewHandle(FindSystemClass(self, "Ljava/io/Serializable;")); 511 CHECK(java_io_Serializable.Get() != nullptr); 512 // We assume that Cloneable/Serializable don't have superinterfaces -- normally we'd have to 513 // crawl up and explicitly list all of the supers as well. 514 array_iftable_.Read()->SetInterface(0, java_lang_Cloneable.Get()); 515 array_iftable_.Read()->SetInterface(1, java_io_Serializable.Get()); 516 517 // Sanity check Class[] and Object[]'s interfaces. GetDirectInterface may cause thread 518 // suspension. 519 CHECK_EQ(java_lang_Cloneable.Get(), 520 mirror::Class::GetDirectInterface(self, class_array_class, 0)); 521 CHECK_EQ(java_io_Serializable.Get(), 522 mirror::Class::GetDirectInterface(self, class_array_class, 1)); 523 CHECK_EQ(java_lang_Cloneable.Get(), 524 mirror::Class::GetDirectInterface(self, object_array_class, 0)); 525 CHECK_EQ(java_io_Serializable.Get(), 526 mirror::Class::GetDirectInterface(self, object_array_class, 1)); 527 // Run Class, ArtField, and ArtMethod through FindSystemClass. This initializes their 528 // dex_cache_ fields and register them in class_table_. 529 CHECK_EQ(java_lang_Class.Get(), FindSystemClass(self, "Ljava/lang/Class;")); 530 531 mirror::Class::SetStatus(java_lang_reflect_ArtMethod, mirror::Class::kStatusNotReady, self); 532 CHECK_EQ(java_lang_reflect_ArtMethod.Get(), 533 FindSystemClass(self, "Ljava/lang/reflect/ArtMethod;")); 534 CHECK_EQ(object_array_string.Get(), 535 FindSystemClass(self, GetClassRootDescriptor(kJavaLangStringArrayClass))); 536 CHECK_EQ(object_array_art_method.Get(), 537 FindSystemClass(self, GetClassRootDescriptor(kJavaLangReflectArtMethodArrayClass))); 538 539 // End of special init trickery, subsequent classes may be loaded via FindSystemClass. 540 541 // Create java.lang.reflect.Proxy root. 542 SetClassRoot(kJavaLangReflectProxy, FindSystemClass(self, "Ljava/lang/reflect/Proxy;")); 543 544 // Create java.lang.reflect.Field.class root. 545 auto* class_root = FindSystemClass(self, "Ljava/lang/reflect/Field;"); 546 CHECK(class_root != nullptr); 547 SetClassRoot(kJavaLangReflectField, class_root); 548 mirror::Field::SetClass(class_root); 549 550 // Create java.lang.reflect.Field array root. 551 class_root = FindSystemClass(self, "[Ljava/lang/reflect/Field;"); 552 CHECK(class_root != nullptr); 553 SetClassRoot(kJavaLangReflectFieldArrayClass, class_root); 554 mirror::Field::SetArrayClass(class_root); 555 556 // Create java.lang.reflect.Constructor.class root and array root. 557 class_root = FindSystemClass(self, "Ljava/lang/reflect/Constructor;"); 558 CHECK(class_root != nullptr); 559 SetClassRoot(kJavaLangReflectConstructor, class_root); 560 mirror::Constructor::SetClass(class_root); 561 class_root = FindSystemClass(self, "[Ljava/lang/reflect/Constructor;"); 562 CHECK(class_root != nullptr); 563 SetClassRoot(kJavaLangReflectConstructorArrayClass, class_root); 564 mirror::Constructor::SetArrayClass(class_root); 565 566 // Create java.lang.reflect.Method.class root and array root. 567 class_root = FindSystemClass(self, "Ljava/lang/reflect/Method;"); 568 CHECK(class_root != nullptr); 569 SetClassRoot(kJavaLangReflectMethod, class_root); 570 mirror::Method::SetClass(class_root); 571 class_root = FindSystemClass(self, "[Ljava/lang/reflect/Method;"); 572 CHECK(class_root != nullptr); 573 SetClassRoot(kJavaLangReflectMethodArrayClass, class_root); 574 mirror::Method::SetArrayClass(class_root); 575 576 // java.lang.ref classes need to be specially flagged, but otherwise are normal classes 577 // finish initializing Reference class 578 mirror::Class::SetStatus(java_lang_ref_Reference, mirror::Class::kStatusNotReady, self); 579 CHECK_EQ(java_lang_ref_Reference.Get(), FindSystemClass(self, "Ljava/lang/ref/Reference;")); 580 CHECK_EQ(java_lang_ref_Reference->GetObjectSize(), mirror::Reference::InstanceSize()); 581 CHECK_EQ(java_lang_ref_Reference->GetClassSize(), mirror::Reference::ClassSize()); 582 class_root = FindSystemClass(self, "Ljava/lang/ref/FinalizerReference;"); 583 class_root->SetAccessFlags(class_root->GetAccessFlags() | 584 kAccClassIsReference | kAccClassIsFinalizerReference); 585 class_root = FindSystemClass(self, "Ljava/lang/ref/PhantomReference;"); 586 class_root->SetAccessFlags(class_root->GetAccessFlags() | kAccClassIsReference | 587 kAccClassIsPhantomReference); 588 class_root = FindSystemClass(self, "Ljava/lang/ref/SoftReference;"); 589 class_root->SetAccessFlags(class_root->GetAccessFlags() | kAccClassIsReference); 590 class_root = FindSystemClass(self, "Ljava/lang/ref/WeakReference;"); 591 class_root->SetAccessFlags(class_root->GetAccessFlags() | kAccClassIsReference | 592 kAccClassIsWeakReference); 593 594 // Setup the ClassLoader, verifying the object_size_. 595 class_root = FindSystemClass(self, "Ljava/lang/ClassLoader;"); 596 CHECK_EQ(class_root->GetObjectSize(), mirror::ClassLoader::InstanceSize()); 597 SetClassRoot(kJavaLangClassLoader, class_root); 598 599 // Set up java.lang.Throwable, java.lang.ClassNotFoundException, and 600 // java.lang.StackTraceElement as a convenience. 601 SetClassRoot(kJavaLangThrowable, FindSystemClass(self, "Ljava/lang/Throwable;")); 602 mirror::Throwable::SetClass(GetClassRoot(kJavaLangThrowable)); 603 SetClassRoot(kJavaLangClassNotFoundException, 604 FindSystemClass(self, "Ljava/lang/ClassNotFoundException;")); 605 SetClassRoot(kJavaLangStackTraceElement, FindSystemClass(self, "Ljava/lang/StackTraceElement;")); 606 SetClassRoot(kJavaLangStackTraceElementArrayClass, 607 FindSystemClass(self, "[Ljava/lang/StackTraceElement;")); 608 mirror::StackTraceElement::SetClass(GetClassRoot(kJavaLangStackTraceElement)); 609 610 // Ensure void type is resolved in the core's dex cache so java.lang.Void is correctly 611 // initialized. 612 { 613 const DexFile& dex_file = java_lang_Object->GetDexFile(); 614 const DexFile::StringId* void_string_id = dex_file.FindStringId("V"); 615 CHECK(void_string_id != nullptr); 616 uint32_t void_string_index = dex_file.GetIndexForStringId(*void_string_id); 617 const DexFile::TypeId* void_type_id = dex_file.FindTypeId(void_string_index); 618 CHECK(void_type_id != nullptr); 619 uint16_t void_type_idx = dex_file.GetIndexForTypeId(*void_type_id); 620 // Now we resolve void type so the dex cache contains it. We use java.lang.Object class 621 // as referrer so the used dex cache is core's one. 622 mirror::Class* resolved_type = ResolveType(dex_file, void_type_idx, java_lang_Object.Get()); 623 CHECK_EQ(resolved_type, GetClassRoot(kPrimitiveVoid)); 624 self->AssertNoPendingException(); 625 } 626 627 FinishInit(self); 628 629 VLOG(startup) << "ClassLinker::InitFromCompiler exiting"; 630} 631 632void ClassLinker::FinishInit(Thread* self) { 633 VLOG(startup) << "ClassLinker::FinishInit entering"; 634 635 // Let the heap know some key offsets into java.lang.ref instances 636 // Note: we hard code the field indexes here rather than using FindInstanceField 637 // as the types of the field can't be resolved prior to the runtime being 638 // fully initialized 639 mirror::Class* java_lang_ref_Reference = GetClassRoot(kJavaLangRefReference); 640 mirror::Class* java_lang_ref_FinalizerReference = 641 FindSystemClass(self, "Ljava/lang/ref/FinalizerReference;"); 642 643 ArtField* pendingNext = java_lang_ref_Reference->GetInstanceField(0); 644 CHECK_STREQ(pendingNext->GetName(), "pendingNext"); 645 CHECK_STREQ(pendingNext->GetTypeDescriptor(), "Ljava/lang/ref/Reference;"); 646 647 ArtField* queue = java_lang_ref_Reference->GetInstanceField(1); 648 CHECK_STREQ(queue->GetName(), "queue"); 649 CHECK_STREQ(queue->GetTypeDescriptor(), "Ljava/lang/ref/ReferenceQueue;"); 650 651 ArtField* queueNext = java_lang_ref_Reference->GetInstanceField(2); 652 CHECK_STREQ(queueNext->GetName(), "queueNext"); 653 CHECK_STREQ(queueNext->GetTypeDescriptor(), "Ljava/lang/ref/Reference;"); 654 655 ArtField* referent = java_lang_ref_Reference->GetInstanceField(3); 656 CHECK_STREQ(referent->GetName(), "referent"); 657 CHECK_STREQ(referent->GetTypeDescriptor(), "Ljava/lang/Object;"); 658 659 ArtField* zombie = java_lang_ref_FinalizerReference->GetInstanceField(2); 660 CHECK_STREQ(zombie->GetName(), "zombie"); 661 CHECK_STREQ(zombie->GetTypeDescriptor(), "Ljava/lang/Object;"); 662 663 // ensure all class_roots_ are initialized 664 for (size_t i = 0; i < kClassRootsMax; i++) { 665 ClassRoot class_root = static_cast<ClassRoot>(i); 666 mirror::Class* klass = GetClassRoot(class_root); 667 CHECK(klass != nullptr); 668 DCHECK(klass->IsArrayClass() || klass->IsPrimitive() || klass->GetDexCache() != nullptr); 669 // note SetClassRoot does additional validation. 670 // if possible add new checks there to catch errors early 671 } 672 673 CHECK(!array_iftable_.IsNull()); 674 675 // disable the slow paths in FindClass and CreatePrimitiveClass now 676 // that Object, Class, and Object[] are setup 677 init_done_ = true; 678 679 VLOG(startup) << "ClassLinker::FinishInit exiting"; 680} 681 682void ClassLinker::RunRootClinits() { 683 Thread* self = Thread::Current(); 684 for (size_t i = 0; i < ClassLinker::kClassRootsMax; ++i) { 685 mirror::Class* c = GetClassRoot(ClassRoot(i)); 686 if (!c->IsArrayClass() && !c->IsPrimitive()) { 687 StackHandleScope<1> hs(self); 688 Handle<mirror::Class> h_class(hs.NewHandle(GetClassRoot(ClassRoot(i)))); 689 EnsureInitialized(self, h_class, true, true); 690 self->AssertNoPendingException(); 691 } 692 } 693} 694 695const OatFile* ClassLinker::RegisterOatFile(const OatFile* oat_file) { 696 WriterMutexLock mu(Thread::Current(), dex_lock_); 697 if (kIsDebugBuild) { 698 for (size_t i = 0; i < oat_files_.size(); ++i) { 699 CHECK_NE(oat_file, oat_files_[i]) << oat_file->GetLocation(); 700 } 701 } 702 VLOG(class_linker) << "Registering " << oat_file->GetLocation(); 703 oat_files_.push_back(oat_file); 704 return oat_file; 705} 706 707OatFile& ClassLinker::GetImageOatFile(gc::space::ImageSpace* space) { 708 VLOG(startup) << "ClassLinker::GetImageOatFile entering"; 709 OatFile* oat_file = space->ReleaseOatFile(); 710 CHECK_EQ(RegisterOatFile(oat_file), oat_file); 711 VLOG(startup) << "ClassLinker::GetImageOatFile exiting"; 712 return *oat_file; 713} 714 715class DexFileAndClassPair : ValueObject { 716 public: 717 DexFileAndClassPair(const DexFile* dex_file, size_t current_class_index, bool from_loaded_oat) 718 : cached_descriptor_(GetClassDescriptor(dex_file, current_class_index)), 719 dex_file_(dex_file), 720 current_class_index_(current_class_index), 721 from_loaded_oat_(from_loaded_oat) {} 722 723 DexFileAndClassPair(const DexFileAndClassPair&) = default; 724 725 DexFileAndClassPair& operator=(const DexFileAndClassPair& rhs) { 726 cached_descriptor_ = rhs.cached_descriptor_; 727 dex_file_ = rhs.dex_file_; 728 current_class_index_ = rhs.current_class_index_; 729 from_loaded_oat_ = rhs.from_loaded_oat_; 730 return *this; 731 } 732 733 const char* GetCachedDescriptor() const { 734 return cached_descriptor_; 735 } 736 737 bool operator<(const DexFileAndClassPair& rhs) const { 738 const char* lhsDescriptor = cached_descriptor_; 739 const char* rhsDescriptor = rhs.cached_descriptor_; 740 int cmp = strcmp(lhsDescriptor, rhsDescriptor); 741 if (cmp != 0) { 742 // Note that the order must be reversed. We want to iterate over the classes in dex files. 743 // They are sorted lexicographically. Thus, the priority-queue must be a min-queue. 744 return cmp > 0; 745 } 746 return dex_file_ < rhs.dex_file_; 747 } 748 749 bool DexFileHasMoreClasses() const { 750 return current_class_index_ + 1 < dex_file_->NumClassDefs(); 751 } 752 753 DexFileAndClassPair GetNext() const { 754 return DexFileAndClassPair(dex_file_, current_class_index_ + 1, from_loaded_oat_); 755 } 756 757 size_t GetCurrentClassIndex() const { 758 return current_class_index_; 759 } 760 761 bool FromLoadedOat() const { 762 return from_loaded_oat_; 763 } 764 765 const DexFile* GetDexFile() const { 766 return dex_file_; 767 } 768 769 void DeleteDexFile() { 770 delete dex_file_; 771 dex_file_ = nullptr; 772 } 773 774 private: 775 static const char* GetClassDescriptor(const DexFile* dex_file, size_t index) { 776 const DexFile::ClassDef& class_def = dex_file->GetClassDef(static_cast<uint16_t>(index)); 777 return dex_file->StringByTypeIdx(class_def.class_idx_); 778 } 779 780 const char* cached_descriptor_; 781 const DexFile* dex_file_; 782 size_t current_class_index_; 783 bool from_loaded_oat_; // We only need to compare mismatches between what we load now 784 // and what was loaded before. Any old duplicates must have been 785 // OK, and any new "internal" duplicates are as well (they must 786 // be from multidex, which resolves correctly). 787}; 788 789static void AddDexFilesFromOat(const OatFile* oat_file, bool already_loaded, 790 std::priority_queue<DexFileAndClassPair>* heap) { 791 const std::vector<const OatDexFile*>& oat_dex_files = oat_file->GetOatDexFiles(); 792 for (const OatDexFile* oat_dex_file : oat_dex_files) { 793 std::string error; 794 std::unique_ptr<const DexFile> dex_file = oat_dex_file->OpenDexFile(&error); 795 if (dex_file.get() == nullptr) { 796 LOG(WARNING) << "Could not create dex file from oat file: " << error; 797 } else { 798 if (dex_file->NumClassDefs() > 0U) { 799 heap->emplace(dex_file.release(), 0U, already_loaded); 800 } 801 } 802 } 803} 804 805static void AddNext(DexFileAndClassPair* original, 806 std::priority_queue<DexFileAndClassPair>* heap) { 807 if (original->DexFileHasMoreClasses()) { 808 heap->push(original->GetNext()); 809 } else { 810 // Need to delete the dex file. 811 original->DeleteDexFile(); 812 } 813} 814 815static void FreeDexFilesInHeap(std::priority_queue<DexFileAndClassPair>* heap) { 816 while (!heap->empty()) { 817 delete heap->top().GetDexFile(); 818 heap->pop(); 819 } 820} 821 822// Check for class-def collisions in dex files. 823// 824// This works by maintaining a heap with one class from each dex file, sorted by the class 825// descriptor. Then a dex-file/class pair is continually removed from the heap and compared 826// against the following top element. If the descriptor is the same, it is now checked whether 827// the two elements agree on whether their dex file was from an already-loaded oat-file or the 828// new oat file. Any disagreement indicates a collision. 829bool ClassLinker::HasCollisions(const OatFile* oat_file, std::string* error_msg) { 830 // Dex files are registered late - once a class is actually being loaded. We have to compare 831 // against the open oat files. Take the dex_lock_ that protects oat_files_ accesses. 832 ReaderMutexLock mu(Thread::Current(), dex_lock_); 833 834 std::priority_queue<DexFileAndClassPair> queue; 835 836 // Add dex files from already loaded oat files, but skip boot. 837 { 838 // To grab the boot oat, look at the dex files in the boot classpath. Any of those is fine, as 839 // they were all compiled into the same oat file. So grab the first one, which is guaranteed to 840 // exist if the boot class-path isn't empty. 841 const OatFile* boot_oat = nullptr; 842 if (!boot_class_path_.empty()) { 843 const DexFile* boot_dex_file = boot_class_path_[0]; 844 // Is it from an oat file? 845 if (boot_dex_file->GetOatDexFile() != nullptr) { 846 boot_oat = boot_dex_file->GetOatDexFile()->GetOatFile(); 847 } 848 } 849 850 for (const OatFile* loaded_oat_file : oat_files_) { 851 if (loaded_oat_file == boot_oat) { 852 continue; 853 } 854 AddDexFilesFromOat(loaded_oat_file, true, &queue); 855 } 856 } 857 858 if (queue.empty()) { 859 // No other oat files, return early. 860 return false; 861 } 862 863 // Add dex files from the oat file to check. 864 AddDexFilesFromOat(oat_file, false, &queue); 865 866 // Now drain the queue. 867 while (!queue.empty()) { 868 DexFileAndClassPair compare_pop = queue.top(); 869 queue.pop(); 870 871 // Compare against the following elements. 872 while (!queue.empty()) { 873 DexFileAndClassPair top = queue.top(); 874 875 if (strcmp(compare_pop.GetCachedDescriptor(), top.GetCachedDescriptor()) == 0) { 876 // Same descriptor. Check whether it's crossing old-oat-files to new-oat-files. 877 if (compare_pop.FromLoadedOat() != top.FromLoadedOat()) { 878 *error_msg = 879 StringPrintf("Found duplicated class when checking oat files: '%s' in %s and %s", 880 compare_pop.GetCachedDescriptor(), 881 compare_pop.GetDexFile()->GetLocation().c_str(), 882 top.GetDexFile()->GetLocation().c_str()); 883 FreeDexFilesInHeap(&queue); 884 return true; 885 } 886 // Pop it. 887 queue.pop(); 888 AddNext(&top, &queue); 889 } else { 890 // Something else. Done here. 891 break; 892 } 893 } 894 AddNext(&compare_pop, &queue); 895 } 896 897 return false; 898} 899 900std::vector<std::unique_ptr<const DexFile>> ClassLinker::OpenDexFilesFromOat( 901 const char* dex_location, const char* oat_location, 902 std::vector<std::string>* error_msgs) { 903 CHECK(error_msgs != nullptr); 904 905 // Verify we aren't holding the mutator lock, which could starve GC if we 906 // have to generate or relocate an oat file. 907 Locks::mutator_lock_->AssertNotHeld(Thread::Current()); 908 909 OatFileAssistant oat_file_assistant(dex_location, oat_location, kRuntimeISA, 910 !Runtime::Current()->IsAotCompiler()); 911 912 // Lock the target oat location to avoid races generating and loading the 913 // oat file. 914 std::string error_msg; 915 if (!oat_file_assistant.Lock(&error_msg)) { 916 // Don't worry too much if this fails. If it does fail, it's unlikely we 917 // can generate an oat file anyway. 918 VLOG(class_linker) << "OatFileAssistant::Lock: " << error_msg; 919 } 920 921 // Check if we already have an up-to-date oat file open. 922 const OatFile* source_oat_file = nullptr; 923 { 924 ReaderMutexLock mu(Thread::Current(), dex_lock_); 925 for (const OatFile* oat_file : oat_files_) { 926 CHECK(oat_file != nullptr); 927 if (oat_file_assistant.GivenOatFileIsUpToDate(*oat_file)) { 928 source_oat_file = oat_file; 929 break; 930 } 931 } 932 } 933 934 // If we didn't have an up-to-date oat file open, try to load one from disk. 935 if (source_oat_file == nullptr) { 936 // Update the oat file on disk if we can. This may fail, but that's okay. 937 // Best effort is all that matters here. 938 if (!oat_file_assistant.MakeUpToDate(&error_msg)) { 939 LOG(WARNING) << error_msg; 940 } 941 942 // Get the oat file on disk. 943 std::unique_ptr<OatFile> oat_file = oat_file_assistant.GetBestOatFile(); 944 if (oat_file.get() != nullptr) { 945 // Take the file only if it has no collisions, or we must take it because of preopting. 946 bool accept_oat_file = !HasCollisions(oat_file.get(), &error_msg); 947 if (!accept_oat_file) { 948 // Failed the collision check. Print warning. 949 if (Runtime::Current()->IsDexFileFallbackEnabled()) { 950 LOG(WARNING) << "Found duplicate classes, falling back to interpreter mode for " 951 << dex_location; 952 } else { 953 LOG(WARNING) << "Found duplicate classes, dex-file-fallback disabled, will be failing to " 954 " load classes for " << dex_location; 955 } 956 LOG(WARNING) << error_msg; 957 958 // However, if the app was part of /system and preopted, there is no original dex file 959 // available. In that case grudgingly accept the oat file. 960 if (!DexFile::MaybeDex(dex_location)) { 961 accept_oat_file = true; 962 LOG(WARNING) << "Dex location " << dex_location << " does not seem to include dex file. " 963 << "Allow oat file use. This is potentially dangerous."; 964 } 965 } 966 967 if (accept_oat_file) { 968 source_oat_file = oat_file.release(); 969 RegisterOatFile(source_oat_file); 970 } 971 } 972 } 973 974 std::vector<std::unique_ptr<const DexFile>> dex_files; 975 976 // Load the dex files from the oat file. 977 if (source_oat_file != nullptr) { 978 dex_files = oat_file_assistant.LoadDexFiles(*source_oat_file, dex_location); 979 if (dex_files.empty()) { 980 error_msgs->push_back("Failed to open dex files from " 981 + source_oat_file->GetLocation()); 982 } 983 } 984 985 // Fall back to running out of the original dex file if we couldn't load any 986 // dex_files from the oat file. 987 if (dex_files.empty()) { 988 if (Runtime::Current()->IsDexFileFallbackEnabled()) { 989 if (!DexFile::Open(dex_location, dex_location, &error_msg, &dex_files)) { 990 LOG(WARNING) << error_msg; 991 error_msgs->push_back("Failed to open dex files from " + std::string(dex_location)); 992 } 993 } else { 994 error_msgs->push_back("Fallback mode disabled, skipping dex files."); 995 } 996 } 997 return dex_files; 998} 999 1000const OatFile* ClassLinker::FindOpenedOatFileFromOatLocation(const std::string& oat_location) { 1001 ReaderMutexLock mu(Thread::Current(), dex_lock_); 1002 for (size_t i = 0; i < oat_files_.size(); i++) { 1003 const OatFile* oat_file = oat_files_[i]; 1004 DCHECK(oat_file != nullptr); 1005 if (oat_file->GetLocation() == oat_location) { 1006 return oat_file; 1007 } 1008 } 1009 return nullptr; 1010} 1011 1012void ClassLinker::InitFromImageInterpretOnlyCallback(mirror::Object* obj, void* arg) { 1013 ClassLinker* class_linker = reinterpret_cast<ClassLinker*>(arg); 1014 DCHECK(obj != nullptr); 1015 DCHECK(class_linker != nullptr); 1016 if (obj->IsArtMethod()) { 1017 mirror::ArtMethod* method = obj->AsArtMethod(); 1018 if (!method->IsNative()) { 1019 const size_t pointer_size = class_linker->image_pointer_size_; 1020 method->SetEntryPointFromInterpreterPtrSize(artInterpreterToInterpreterBridge, pointer_size); 1021 if (!method->IsRuntimeMethod() && method != Runtime::Current()->GetResolutionMethod()) { 1022 method->SetEntryPointFromQuickCompiledCodePtrSize(GetQuickToInterpreterBridge(), 1023 pointer_size); 1024 } 1025 } 1026 } 1027} 1028 1029void SanityCheckObjectsCallback(mirror::Object* obj, void* arg ATTRIBUTE_UNUSED) 1030 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1031 DCHECK(obj != nullptr); 1032 CHECK(obj->GetClass() != nullptr) << "Null class " << obj; 1033 CHECK(obj->GetClass()->GetClass() != nullptr) << "Null class class " << obj; 1034 if (obj->IsClass()) { 1035 auto klass = obj->AsClass(); 1036 ArtField* fields[2] = { klass->GetSFields(), klass->GetIFields() }; 1037 size_t num_fields[2] = { klass->NumStaticFields(), klass->NumInstanceFields() }; 1038 for (size_t i = 0; i < 2; ++i) { 1039 for (size_t j = 0; j < num_fields[i]; ++j) { 1040 CHECK_EQ(fields[i][j].GetDeclaringClass(), klass); 1041 } 1042 } 1043 } 1044} 1045 1046void ClassLinker::InitFromImage() { 1047 VLOG(startup) << "ClassLinker::InitFromImage entering"; 1048 CHECK(!init_done_); 1049 1050 Runtime* const runtime = Runtime::Current(); 1051 Thread* const self = Thread::Current(); 1052 gc::Heap* const heap = runtime->GetHeap(); 1053 gc::space::ImageSpace* const space = heap->GetImageSpace(); 1054 dex_cache_image_class_lookup_required_ = true; 1055 CHECK(space != nullptr); 1056 OatFile& oat_file = GetImageOatFile(space); 1057 CHECK_EQ(oat_file.GetOatHeader().GetImageFileLocationOatChecksum(), 0U); 1058 CHECK_EQ(oat_file.GetOatHeader().GetImageFileLocationOatDataBegin(), 0U); 1059 const char* image_file_location = oat_file.GetOatHeader(). 1060 GetStoreValueByKey(OatHeader::kImageLocationKey); 1061 CHECK(image_file_location == nullptr || *image_file_location == 0); 1062 quick_resolution_trampoline_ = oat_file.GetOatHeader().GetQuickResolutionTrampoline(); 1063 quick_imt_conflict_trampoline_ = oat_file.GetOatHeader().GetQuickImtConflictTrampoline(); 1064 quick_generic_jni_trampoline_ = oat_file.GetOatHeader().GetQuickGenericJniTrampoline(); 1065 quick_to_interpreter_bridge_trampoline_ = oat_file.GetOatHeader().GetQuickToInterpreterBridge(); 1066 mirror::Object* dex_caches_object = space->GetImageHeader().GetImageRoot(ImageHeader::kDexCaches); 1067 mirror::ObjectArray<mirror::DexCache>* dex_caches = 1068 dex_caches_object->AsObjectArray<mirror::DexCache>(); 1069 1070 StackHandleScope<1> hs(self); 1071 Handle<mirror::ObjectArray<mirror::Class>> class_roots(hs.NewHandle( 1072 space->GetImageHeader().GetImageRoot(ImageHeader::kClassRoots)-> 1073 AsObjectArray<mirror::Class>())); 1074 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class>>(class_roots.Get()); 1075 1076 // Special case of setting up the String class early so that we can test arbitrary objects 1077 // as being Strings or not 1078 mirror::String::SetClass(GetClassRoot(kJavaLangString)); 1079 1080 CHECK_EQ(oat_file.GetOatHeader().GetDexFileCount(), 1081 static_cast<uint32_t>(dex_caches->GetLength())); 1082 for (int32_t i = 0; i < dex_caches->GetLength(); i++) { 1083 StackHandleScope<1> hs2(self); 1084 Handle<mirror::DexCache> dex_cache(hs2.NewHandle(dex_caches->Get(i))); 1085 const std::string& dex_file_location(dex_cache->GetLocation()->ToModifiedUtf8()); 1086 const OatFile::OatDexFile* oat_dex_file = oat_file.GetOatDexFile(dex_file_location.c_str(), 1087 nullptr); 1088 CHECK(oat_dex_file != nullptr) << oat_file.GetLocation() << " " << dex_file_location; 1089 std::string error_msg; 1090 std::unique_ptr<const DexFile> dex_file = oat_dex_file->OpenDexFile(&error_msg); 1091 if (dex_file.get() == nullptr) { 1092 LOG(FATAL) << "Failed to open dex file " << dex_file_location 1093 << " from within oat file " << oat_file.GetLocation() 1094 << " error '" << error_msg << "'"; 1095 UNREACHABLE(); 1096 } 1097 1098 CHECK_EQ(dex_file->GetLocationChecksum(), oat_dex_file->GetDexFileLocationChecksum()); 1099 1100 AppendToBootClassPath(*dex_file.get(), dex_cache); 1101 opened_dex_files_.push_back(std::move(dex_file)); 1102 } 1103 1104 // Set classes on AbstractMethod early so that IsMethod tests can be performed during the live 1105 // bitmap walk. 1106 mirror::ArtMethod::SetClass(GetClassRoot(kJavaLangReflectArtMethod)); 1107 size_t art_method_object_size = mirror::ArtMethod::GetJavaLangReflectArtMethod()->GetObjectSize(); 1108 if (!runtime->IsAotCompiler()) { 1109 // Aot compiler supports having an image with a different pointer size than the runtime. This 1110 // happens on the host for compile 32 bit tests since we use a 64 bit libart compiler. We may 1111 // also use 32 bit dex2oat on a system with 64 bit apps. 1112 CHECK_EQ(art_method_object_size, mirror::ArtMethod::InstanceSize(sizeof(void*))) 1113 << sizeof(void*); 1114 } 1115 if (art_method_object_size == mirror::ArtMethod::InstanceSize(4)) { 1116 image_pointer_size_ = 4; 1117 } else { 1118 CHECK_EQ(art_method_object_size, mirror::ArtMethod::InstanceSize(8)); 1119 image_pointer_size_ = 8; 1120 } 1121 1122 // Set entry point to interpreter if in InterpretOnly mode. 1123 if (!runtime->IsAotCompiler() && runtime->GetInstrumentation()->InterpretOnly()) { 1124 heap->VisitObjects(InitFromImageInterpretOnlyCallback, this); 1125 } 1126 if (kSanityCheckObjects) { 1127 for (int32_t i = 0; i < dex_caches->GetLength(); i++) { 1128 auto* dex_cache = dex_caches->Get(i); 1129 for (size_t j = 0; j < dex_cache->NumResolvedFields(); ++j) { 1130 auto* field = dex_cache->GetResolvedField(j, image_pointer_size_); 1131 if (field != nullptr) { 1132 CHECK(field->GetDeclaringClass()->GetClass() != nullptr); 1133 } 1134 } 1135 } 1136 heap->VisitObjects(SanityCheckObjectsCallback, nullptr); 1137 } 1138 1139 // reinit class_roots_ 1140 mirror::Class::SetClassClass(class_roots->Get(kJavaLangClass)); 1141 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class>>(class_roots.Get()); 1142 1143 // reinit array_iftable_ from any array class instance, they should be == 1144 array_iftable_ = GcRoot<mirror::IfTable>(GetClassRoot(kObjectArrayClass)->GetIfTable()); 1145 DCHECK_EQ(array_iftable_.Read(), GetClassRoot(kBooleanArrayClass)->GetIfTable()); 1146 // String class root was set above 1147 mirror::Field::SetClass(GetClassRoot(kJavaLangReflectField)); 1148 mirror::Field::SetArrayClass(GetClassRoot(kJavaLangReflectFieldArrayClass)); 1149 mirror::Constructor::SetClass(GetClassRoot(kJavaLangReflectConstructor)); 1150 mirror::Constructor::SetArrayClass(GetClassRoot(kJavaLangReflectConstructorArrayClass)); 1151 mirror::Method::SetClass(GetClassRoot(kJavaLangReflectMethod)); 1152 mirror::Method::SetArrayClass(GetClassRoot(kJavaLangReflectMethodArrayClass)); 1153 mirror::Reference::SetClass(GetClassRoot(kJavaLangRefReference)); 1154 mirror::BooleanArray::SetArrayClass(GetClassRoot(kBooleanArrayClass)); 1155 mirror::ByteArray::SetArrayClass(GetClassRoot(kByteArrayClass)); 1156 mirror::CharArray::SetArrayClass(GetClassRoot(kCharArrayClass)); 1157 mirror::DoubleArray::SetArrayClass(GetClassRoot(kDoubleArrayClass)); 1158 mirror::FloatArray::SetArrayClass(GetClassRoot(kFloatArrayClass)); 1159 mirror::IntArray::SetArrayClass(GetClassRoot(kIntArrayClass)); 1160 mirror::LongArray::SetArrayClass(GetClassRoot(kLongArrayClass)); 1161 mirror::ShortArray::SetArrayClass(GetClassRoot(kShortArrayClass)); 1162 mirror::Throwable::SetClass(GetClassRoot(kJavaLangThrowable)); 1163 mirror::StackTraceElement::SetClass(GetClassRoot(kJavaLangStackTraceElement)); 1164 1165 FinishInit(self); 1166 1167 VLOG(startup) << "ClassLinker::InitFromImage exiting"; 1168} 1169 1170void ClassLinker::VisitClassRoots(RootVisitor* visitor, VisitRootFlags flags) { 1171 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 1172 BufferedRootVisitor<kDefaultBufferedRootCount> buffered_visitor( 1173 visitor, RootInfo(kRootStickyClass)); 1174 if ((flags & kVisitRootFlagAllRoots) != 0) { 1175 for (GcRoot<mirror::Class>& root : class_table_) { 1176 buffered_visitor.VisitRoot(root); 1177 root.Read()->VisitFieldRoots(buffered_visitor); 1178 } 1179 // PreZygote classes can't move so we won't need to update fields' declaring classes. 1180 for (GcRoot<mirror::Class>& root : pre_zygote_class_table_) { 1181 buffered_visitor.VisitRoot(root); 1182 root.Read()->VisitFieldRoots(buffered_visitor); 1183 } 1184 } else if ((flags & kVisitRootFlagNewRoots) != 0) { 1185 for (auto& root : new_class_roots_) { 1186 mirror::Class* old_ref = root.Read<kWithoutReadBarrier>(); 1187 old_ref->VisitFieldRoots(buffered_visitor); 1188 root.VisitRoot(visitor, RootInfo(kRootStickyClass)); 1189 mirror::Class* new_ref = root.Read<kWithoutReadBarrier>(); 1190 if (UNLIKELY(new_ref != old_ref)) { 1191 // Uh ohes, GC moved a root in the log. Need to search the class_table and update the 1192 // corresponding object. This is slow, but luckily for us, this may only happen with a 1193 // concurrent moving GC. 1194 auto it = class_table_.Find(GcRoot<mirror::Class>(old_ref)); 1195 DCHECK(it != class_table_.end()); 1196 *it = GcRoot<mirror::Class>(new_ref); 1197 } 1198 } 1199 } 1200 buffered_visitor.Flush(); // Flush before clearing new_class_roots_. 1201 if ((flags & kVisitRootFlagClearRootLog) != 0) { 1202 new_class_roots_.clear(); 1203 } 1204 if ((flags & kVisitRootFlagStartLoggingNewRoots) != 0) { 1205 log_new_class_table_roots_ = true; 1206 } else if ((flags & kVisitRootFlagStopLoggingNewRoots) != 0) { 1207 log_new_class_table_roots_ = false; 1208 } 1209 // We deliberately ignore the class roots in the image since we 1210 // handle image roots by using the MS/CMS rescanning of dirty cards. 1211} 1212 1213// Keep in sync with InitCallback. Anything we visit, we need to 1214// reinit references to when reinitializing a ClassLinker from a 1215// mapped image. 1216void ClassLinker::VisitRoots(RootVisitor* visitor, VisitRootFlags flags) { 1217 class_roots_.VisitRoot(visitor, RootInfo(kRootVMInternal)); 1218 Thread* const self = Thread::Current(); 1219 { 1220 ReaderMutexLock mu(self, dex_lock_); 1221 if ((flags & kVisitRootFlagAllRoots) != 0) { 1222 for (GcRoot<mirror::DexCache>& dex_cache : dex_caches_) { 1223 dex_cache.VisitRoot(visitor, RootInfo(kRootVMInternal)); 1224 } 1225 } else if ((flags & kVisitRootFlagNewRoots) != 0) { 1226 for (size_t index : new_dex_cache_roots_) { 1227 dex_caches_[index].VisitRoot(visitor, RootInfo(kRootVMInternal)); 1228 } 1229 } 1230 if ((flags & kVisitRootFlagClearRootLog) != 0) { 1231 new_dex_cache_roots_.clear(); 1232 } 1233 if ((flags & kVisitRootFlagStartLoggingNewRoots) != 0) { 1234 log_new_dex_caches_roots_ = true; 1235 } else if ((flags & kVisitRootFlagStopLoggingNewRoots) != 0) { 1236 log_new_dex_caches_roots_ = false; 1237 } 1238 } 1239 VisitClassRoots(visitor, flags); 1240 array_iftable_.VisitRoot(visitor, RootInfo(kRootVMInternal)); 1241 for (size_t i = 0; i < kFindArrayCacheSize; ++i) { 1242 find_array_class_cache_[i].VisitRootIfNonNull(visitor, RootInfo(kRootVMInternal)); 1243 } 1244} 1245 1246void ClassLinker::VisitClasses(ClassVisitor* visitor, void* arg) { 1247 if (dex_cache_image_class_lookup_required_) { 1248 MoveImageClassesToClassTable(); 1249 } 1250 // TODO: why isn't this a ReaderMutexLock? 1251 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 1252 for (GcRoot<mirror::Class>& root : class_table_) { 1253 if (!visitor(root.Read(), arg)) { 1254 return; 1255 } 1256 } 1257 for (GcRoot<mirror::Class>& root : pre_zygote_class_table_) { 1258 if (!visitor(root.Read(), arg)) { 1259 return; 1260 } 1261 } 1262} 1263 1264static bool GetClassesVisitorSet(mirror::Class* c, void* arg) { 1265 std::set<mirror::Class*>* classes = reinterpret_cast<std::set<mirror::Class*>*>(arg); 1266 classes->insert(c); 1267 return true; 1268} 1269 1270struct GetClassesVisitorArrayArg { 1271 Handle<mirror::ObjectArray<mirror::Class>>* classes; 1272 int32_t index; 1273 bool success; 1274}; 1275 1276static bool GetClassesVisitorArray(mirror::Class* c, void* varg) 1277 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1278 GetClassesVisitorArrayArg* arg = reinterpret_cast<GetClassesVisitorArrayArg*>(varg); 1279 if (arg->index < (*arg->classes)->GetLength()) { 1280 (*arg->classes)->Set(arg->index, c); 1281 arg->index++; 1282 return true; 1283 } else { 1284 arg->success = false; 1285 return false; 1286 } 1287} 1288 1289void ClassLinker::VisitClassesWithoutClassesLock(ClassVisitor* visitor, void* arg) { 1290 // TODO: it may be possible to avoid secondary storage if we iterate over dex caches. The problem 1291 // is avoiding duplicates. 1292 if (!kMovingClasses) { 1293 std::set<mirror::Class*> classes; 1294 VisitClasses(GetClassesVisitorSet, &classes); 1295 for (mirror::Class* klass : classes) { 1296 if (!visitor(klass, arg)) { 1297 return; 1298 } 1299 } 1300 } else { 1301 Thread* self = Thread::Current(); 1302 StackHandleScope<1> hs(self); 1303 MutableHandle<mirror::ObjectArray<mirror::Class>> classes = 1304 hs.NewHandle<mirror::ObjectArray<mirror::Class>>(nullptr); 1305 GetClassesVisitorArrayArg local_arg; 1306 local_arg.classes = &classes; 1307 local_arg.success = false; 1308 // We size the array assuming classes won't be added to the class table during the visit. 1309 // If this assumption fails we iterate again. 1310 while (!local_arg.success) { 1311 size_t class_table_size; 1312 { 1313 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 1314 class_table_size = class_table_.Size() + pre_zygote_class_table_.Size(); 1315 } 1316 mirror::Class* class_type = mirror::Class::GetJavaLangClass(); 1317 mirror::Class* array_of_class = FindArrayClass(self, &class_type); 1318 classes.Assign( 1319 mirror::ObjectArray<mirror::Class>::Alloc(self, array_of_class, class_table_size)); 1320 CHECK(classes.Get() != nullptr); // OOME. 1321 local_arg.index = 0; 1322 local_arg.success = true; 1323 VisitClasses(GetClassesVisitorArray, &local_arg); 1324 } 1325 for (int32_t i = 0; i < classes->GetLength(); ++i) { 1326 // If the class table shrank during creation of the clases array we expect null elements. If 1327 // the class table grew then the loop repeats. If classes are created after the loop has 1328 // finished then we don't visit. 1329 mirror::Class* klass = classes->Get(i); 1330 if (klass != nullptr && !visitor(klass, arg)) { 1331 return; 1332 } 1333 } 1334 } 1335} 1336 1337ClassLinker::~ClassLinker() { 1338 mirror::ArtMethod::ResetClass(); 1339 mirror::Class::ResetClass(); 1340 mirror::Constructor::ResetClass(); 1341 mirror::Field::ResetClass(); 1342 mirror::Method::ResetClass(); 1343 mirror::Reference::ResetClass(); 1344 mirror::StackTraceElement::ResetClass(); 1345 mirror::String::ResetClass(); 1346 mirror::Throwable::ResetClass(); 1347 mirror::BooleanArray::ResetArrayClass(); 1348 mirror::ByteArray::ResetArrayClass(); 1349 mirror::CharArray::ResetArrayClass(); 1350 mirror::Constructor::ResetArrayClass(); 1351 mirror::DoubleArray::ResetArrayClass(); 1352 mirror::Field::ResetArrayClass(); 1353 mirror::FloatArray::ResetArrayClass(); 1354 mirror::Method::ResetArrayClass(); 1355 mirror::IntArray::ResetArrayClass(); 1356 mirror::LongArray::ResetArrayClass(); 1357 mirror::ShortArray::ResetArrayClass(); 1358 STLDeleteElements(&oat_files_); 1359} 1360 1361mirror::DexCache* ClassLinker::AllocDexCache(Thread* self, const DexFile& dex_file) { 1362 gc::Heap* const heap = Runtime::Current()->GetHeap(); 1363 StackHandleScope<16> hs(self); 1364 Handle<mirror::Class> dex_cache_class(hs.NewHandle(GetClassRoot(kJavaLangDexCache))); 1365 Handle<mirror::DexCache> dex_cache( 1366 hs.NewHandle(down_cast<mirror::DexCache*>( 1367 heap->AllocObject<true>(self, dex_cache_class.Get(), dex_cache_class->GetObjectSize(), 1368 VoidFunctor())))); 1369 if (dex_cache.Get() == nullptr) { 1370 return nullptr; 1371 } 1372 Handle<mirror::String> 1373 location(hs.NewHandle(intern_table_->InternStrong(dex_file.GetLocation().c_str()))); 1374 if (location.Get() == nullptr) { 1375 return nullptr; 1376 } 1377 Handle<mirror::ObjectArray<mirror::String>> 1378 strings(hs.NewHandle(AllocStringArray(self, dex_file.NumStringIds()))); 1379 if (strings.Get() == nullptr) { 1380 return nullptr; 1381 } 1382 Handle<mirror::ObjectArray<mirror::Class>> 1383 types(hs.NewHandle(AllocClassArray(self, dex_file.NumTypeIds()))); 1384 if (types.Get() == nullptr) { 1385 return nullptr; 1386 } 1387 Handle<mirror::ObjectArray<mirror::ArtMethod>> 1388 methods(hs.NewHandle(AllocArtMethodArray(self, dex_file.NumMethodIds()))); 1389 if (methods.Get() == nullptr) { 1390 return nullptr; 1391 } 1392 Handle<mirror::Array> fields; 1393 if (image_pointer_size_ == 8) { 1394 fields = hs.NewHandle<mirror::Array>(mirror::LongArray::Alloc(self, dex_file.NumFieldIds())); 1395 } else { 1396 fields = hs.NewHandle<mirror::Array>(mirror::IntArray::Alloc(self, dex_file.NumFieldIds())); 1397 } 1398 if (fields.Get() == nullptr) { 1399 return nullptr; 1400 } 1401 dex_cache->Init(&dex_file, location.Get(), strings.Get(), types.Get(), methods.Get(), 1402 fields.Get()); 1403 return dex_cache.Get(); 1404} 1405 1406mirror::Class* ClassLinker::AllocClass(Thread* self, mirror::Class* java_lang_Class, 1407 uint32_t class_size) { 1408 DCHECK_GE(class_size, sizeof(mirror::Class)); 1409 gc::Heap* heap = Runtime::Current()->GetHeap(); 1410 mirror::Class::InitializeClassVisitor visitor(class_size); 1411 mirror::Object* k = kMovingClasses ? 1412 heap->AllocObject<true>(self, java_lang_Class, class_size, visitor) : 1413 heap->AllocNonMovableObject<true>(self, java_lang_Class, class_size, visitor); 1414 if (UNLIKELY(k == nullptr)) { 1415 CHECK(self->IsExceptionPending()); // OOME. 1416 return nullptr; 1417 } 1418 return k->AsClass(); 1419} 1420 1421mirror::Class* ClassLinker::AllocClass(Thread* self, uint32_t class_size) { 1422 return AllocClass(self, GetClassRoot(kJavaLangClass), class_size); 1423} 1424 1425mirror::ArtMethod* ClassLinker::AllocArtMethod(Thread* self) { 1426 return down_cast<mirror::ArtMethod*>( 1427 GetClassRoot(kJavaLangReflectArtMethod)->AllocNonMovableObject(self)); 1428} 1429 1430mirror::ObjectArray<mirror::StackTraceElement>* ClassLinker::AllocStackTraceElementArray( 1431 Thread* self, size_t length) { 1432 return mirror::ObjectArray<mirror::StackTraceElement>::Alloc( 1433 self, GetClassRoot(kJavaLangStackTraceElementArrayClass), length); 1434} 1435 1436mirror::Class* ClassLinker::EnsureResolved(Thread* self, const char* descriptor, 1437 mirror::Class* klass) { 1438 DCHECK(klass != nullptr); 1439 1440 // For temporary classes we must wait for them to be retired. 1441 if (init_done_ && klass->IsTemp()) { 1442 CHECK(!klass->IsResolved()); 1443 if (klass->IsErroneous()) { 1444 ThrowEarlierClassFailure(klass); 1445 return nullptr; 1446 } 1447 StackHandleScope<1> hs(self); 1448 Handle<mirror::Class> h_class(hs.NewHandle(klass)); 1449 ObjectLock<mirror::Class> lock(self, h_class); 1450 // Loop and wait for the resolving thread to retire this class. 1451 while (!h_class->IsRetired() && !h_class->IsErroneous()) { 1452 lock.WaitIgnoringInterrupts(); 1453 } 1454 if (h_class->IsErroneous()) { 1455 ThrowEarlierClassFailure(h_class.Get()); 1456 return nullptr; 1457 } 1458 CHECK(h_class->IsRetired()); 1459 // Get the updated class from class table. 1460 klass = LookupClass(self, descriptor, ComputeModifiedUtf8Hash(descriptor), 1461 h_class.Get()->GetClassLoader()); 1462 } 1463 1464 // Wait for the class if it has not already been linked. 1465 if (!klass->IsResolved() && !klass->IsErroneous()) { 1466 StackHandleScope<1> hs(self); 1467 HandleWrapper<mirror::Class> h_class(hs.NewHandleWrapper(&klass)); 1468 ObjectLock<mirror::Class> lock(self, h_class); 1469 // Check for circular dependencies between classes. 1470 if (!h_class->IsResolved() && h_class->GetClinitThreadId() == self->GetTid()) { 1471 ThrowClassCircularityError(h_class.Get()); 1472 mirror::Class::SetStatus(h_class, mirror::Class::kStatusError, self); 1473 return nullptr; 1474 } 1475 // Wait for the pending initialization to complete. 1476 while (!h_class->IsResolved() && !h_class->IsErroneous()) { 1477 lock.WaitIgnoringInterrupts(); 1478 } 1479 } 1480 1481 if (klass->IsErroneous()) { 1482 ThrowEarlierClassFailure(klass); 1483 return nullptr; 1484 } 1485 // Return the loaded class. No exceptions should be pending. 1486 CHECK(klass->IsResolved()) << PrettyClass(klass); 1487 self->AssertNoPendingException(); 1488 return klass; 1489} 1490 1491typedef std::pair<const DexFile*, const DexFile::ClassDef*> ClassPathEntry; 1492 1493// Search a collection of DexFiles for a descriptor 1494ClassPathEntry FindInClassPath(const char* descriptor, 1495 size_t hash, const std::vector<const DexFile*>& class_path) { 1496 for (const DexFile* dex_file : class_path) { 1497 const DexFile::ClassDef* dex_class_def = dex_file->FindClassDef(descriptor, hash); 1498 if (dex_class_def != nullptr) { 1499 return ClassPathEntry(dex_file, dex_class_def); 1500 } 1501 } 1502 return ClassPathEntry(nullptr, nullptr); 1503} 1504 1505static bool IsBootClassLoader(ScopedObjectAccessAlreadyRunnable& soa, 1506 mirror::ClassLoader* class_loader) 1507 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 1508 return class_loader == nullptr || 1509 class_loader->GetClass() == 1510 soa.Decode<mirror::Class*>(WellKnownClasses::java_lang_BootClassLoader); 1511} 1512 1513bool ClassLinker::FindClassInPathClassLoader(ScopedObjectAccessAlreadyRunnable& soa, 1514 Thread* self, const char* descriptor, 1515 size_t hash, 1516 Handle<mirror::ClassLoader> class_loader, 1517 mirror::Class** result) { 1518 // Termination case: boot class-loader. 1519 if (IsBootClassLoader(soa, class_loader.Get())) { 1520 // The boot class loader, search the boot class path. 1521 ClassPathEntry pair = FindInClassPath(descriptor, hash, boot_class_path_); 1522 if (pair.second != nullptr) { 1523 mirror::Class* klass = LookupClass(self, descriptor, hash, nullptr); 1524 if (klass != nullptr) { 1525 *result = EnsureResolved(self, descriptor, klass); 1526 } else { 1527 *result = DefineClass(self, descriptor, hash, NullHandle<mirror::ClassLoader>(), 1528 *pair.first, *pair.second); 1529 } 1530 if (*result == nullptr) { 1531 CHECK(self->IsExceptionPending()) << descriptor; 1532 self->ClearException(); 1533 } 1534 } else { 1535 *result = nullptr; 1536 } 1537 return true; 1538 } 1539 1540 // Unsupported class-loader? 1541 if (class_loader->GetClass() != 1542 soa.Decode<mirror::Class*>(WellKnownClasses::dalvik_system_PathClassLoader)) { 1543 *result = nullptr; 1544 return false; 1545 } 1546 1547 // Handles as RegisterDexFile may allocate dex caches (and cause thread suspension). 1548 StackHandleScope<4> hs(self); 1549 Handle<mirror::ClassLoader> h_parent(hs.NewHandle(class_loader->GetParent())); 1550 bool recursive_result = FindClassInPathClassLoader(soa, self, descriptor, hash, h_parent, result); 1551 1552 if (!recursive_result) { 1553 // Something wrong up the chain. 1554 return false; 1555 } 1556 1557 if (*result != nullptr) { 1558 // Found the class up the chain. 1559 return true; 1560 } 1561 1562 // Handle this step. 1563 // Handle as if this is the child PathClassLoader. 1564 // The class loader is a PathClassLoader which inherits from BaseDexClassLoader. 1565 // We need to get the DexPathList and loop through it. 1566 ArtField* const cookie_field = soa.DecodeField(WellKnownClasses::dalvik_system_DexFile_cookie); 1567 ArtField* const dex_file_field = 1568 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList__Element_dexFile); 1569 mirror::Object* dex_path_list = 1570 soa.DecodeField(WellKnownClasses::dalvik_system_PathClassLoader_pathList)-> 1571 GetObject(class_loader.Get()); 1572 if (dex_path_list != nullptr && dex_file_field != nullptr && cookie_field != nullptr) { 1573 // DexPathList has an array dexElements of Elements[] which each contain a dex file. 1574 mirror::Object* dex_elements_obj = 1575 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList_dexElements)-> 1576 GetObject(dex_path_list); 1577 // Loop through each dalvik.system.DexPathList$Element's dalvik.system.DexFile and look 1578 // at the mCookie which is a DexFile vector. 1579 if (dex_elements_obj != nullptr) { 1580 Handle<mirror::ObjectArray<mirror::Object>> dex_elements = 1581 hs.NewHandle(dex_elements_obj->AsObjectArray<mirror::Object>()); 1582 for (int32_t i = 0; i < dex_elements->GetLength(); ++i) { 1583 mirror::Object* element = dex_elements->GetWithoutChecks(i); 1584 if (element == nullptr) { 1585 // Should never happen, fall back to java code to throw a NPE. 1586 break; 1587 } 1588 mirror::Object* dex_file = dex_file_field->GetObject(element); 1589 if (dex_file != nullptr) { 1590 mirror::LongArray* long_array = cookie_field->GetObject(dex_file)->AsLongArray(); 1591 if (long_array == nullptr) { 1592 // This should never happen so log a warning. 1593 LOG(WARNING) << "Null DexFile::mCookie for " << descriptor; 1594 break; 1595 } 1596 int32_t long_array_size = long_array->GetLength(); 1597 for (int32_t j = 0; j < long_array_size; ++j) { 1598 const DexFile* cp_dex_file = reinterpret_cast<const DexFile*>(static_cast<uintptr_t>( 1599 long_array->GetWithoutChecks(j))); 1600 const DexFile::ClassDef* dex_class_def = cp_dex_file->FindClassDef(descriptor, hash); 1601 if (dex_class_def != nullptr) { 1602 RegisterDexFile(*cp_dex_file); 1603 mirror::Class* klass = DefineClass(self, descriptor, hash, class_loader, 1604 *cp_dex_file, *dex_class_def); 1605 if (klass == nullptr) { 1606 CHECK(self->IsExceptionPending()) << descriptor; 1607 self->ClearException(); 1608 // TODO: Is it really right to break here, and not check the other dex files? 1609 return true; 1610 } 1611 *result = klass; 1612 return true; 1613 } 1614 } 1615 } 1616 } 1617 } 1618 self->AssertNoPendingException(); 1619 } 1620 1621 // Result is still null from the parent call, no need to set it again... 1622 return true; 1623} 1624 1625mirror::Class* ClassLinker::FindClass(Thread* self, const char* descriptor, 1626 Handle<mirror::ClassLoader> class_loader) { 1627 DCHECK_NE(*descriptor, '\0') << "descriptor is empty string"; 1628 DCHECK(self != nullptr); 1629 self->AssertNoPendingException(); 1630 if (descriptor[1] == '\0') { 1631 // only the descriptors of primitive types should be 1 character long, also avoid class lookup 1632 // for primitive classes that aren't backed by dex files. 1633 return FindPrimitiveClass(descriptor[0]); 1634 } 1635 const size_t hash = ComputeModifiedUtf8Hash(descriptor); 1636 // Find the class in the loaded classes table. 1637 mirror::Class* klass = LookupClass(self, descriptor, hash, class_loader.Get()); 1638 if (klass != nullptr) { 1639 return EnsureResolved(self, descriptor, klass); 1640 } 1641 // Class is not yet loaded. 1642 if (descriptor[0] == '[') { 1643 return CreateArrayClass(self, descriptor, hash, class_loader); 1644 } else if (class_loader.Get() == nullptr) { 1645 // The boot class loader, search the boot class path. 1646 ClassPathEntry pair = FindInClassPath(descriptor, hash, boot_class_path_); 1647 if (pair.second != nullptr) { 1648 return DefineClass(self, descriptor, hash, NullHandle<mirror::ClassLoader>(), *pair.first, 1649 *pair.second); 1650 } else { 1651 // The boot class loader is searched ahead of the application class loader, failures are 1652 // expected and will be wrapped in a ClassNotFoundException. Use the pre-allocated error to 1653 // trigger the chaining with a proper stack trace. 1654 mirror::Throwable* pre_allocated = Runtime::Current()->GetPreAllocatedNoClassDefFoundError(); 1655 self->SetException(pre_allocated); 1656 return nullptr; 1657 } 1658 } else { 1659 ScopedObjectAccessUnchecked soa(self); 1660 mirror::Class* cp_klass; 1661 if (FindClassInPathClassLoader(soa, self, descriptor, hash, class_loader, &cp_klass)) { 1662 // The chain was understood. So the value in cp_klass is either the class we were looking 1663 // for, or not found. 1664 if (cp_klass != nullptr) { 1665 return cp_klass; 1666 } 1667 // TODO: We handle the boot classpath loader in FindClassInPathClassLoader. Try to unify this 1668 // and the branch above. TODO: throw the right exception here. 1669 1670 // We'll let the Java-side rediscover all this and throw the exception with the right stack 1671 // trace. 1672 } 1673 1674 if (Runtime::Current()->IsAotCompiler()) { 1675 // Oops, compile-time, can't run actual class-loader code. 1676 mirror::Throwable* pre_allocated = Runtime::Current()->GetPreAllocatedNoClassDefFoundError(); 1677 self->SetException(pre_allocated); 1678 return nullptr; 1679 } 1680 1681 ScopedLocalRef<jobject> class_loader_object(soa.Env(), 1682 soa.AddLocalReference<jobject>(class_loader.Get())); 1683 std::string class_name_string(DescriptorToDot(descriptor)); 1684 ScopedLocalRef<jobject> result(soa.Env(), nullptr); 1685 { 1686 ScopedThreadStateChange tsc(self, kNative); 1687 ScopedLocalRef<jobject> class_name_object(soa.Env(), 1688 soa.Env()->NewStringUTF(class_name_string.c_str())); 1689 if (class_name_object.get() == nullptr) { 1690 DCHECK(self->IsExceptionPending()); // OOME. 1691 return nullptr; 1692 } 1693 CHECK(class_loader_object.get() != nullptr); 1694 result.reset(soa.Env()->CallObjectMethod(class_loader_object.get(), 1695 WellKnownClasses::java_lang_ClassLoader_loadClass, 1696 class_name_object.get())); 1697 } 1698 if (self->IsExceptionPending()) { 1699 // If the ClassLoader threw, pass that exception up. 1700 return nullptr; 1701 } else if (result.get() == nullptr) { 1702 // broken loader - throw NPE to be compatible with Dalvik 1703 ThrowNullPointerException(StringPrintf("ClassLoader.loadClass returned null for %s", 1704 class_name_string.c_str()).c_str()); 1705 return nullptr; 1706 } else { 1707 // success, return mirror::Class* 1708 return soa.Decode<mirror::Class*>(result.get()); 1709 } 1710 } 1711 UNREACHABLE(); 1712} 1713 1714mirror::Class* ClassLinker::DefineClass(Thread* self, const char* descriptor, size_t hash, 1715 Handle<mirror::ClassLoader> class_loader, 1716 const DexFile& dex_file, 1717 const DexFile::ClassDef& dex_class_def) { 1718 StackHandleScope<3> hs(self); 1719 auto klass = hs.NewHandle<mirror::Class>(nullptr); 1720 1721 // Load the class from the dex file. 1722 if (UNLIKELY(!init_done_)) { 1723 // finish up init of hand crafted class_roots_ 1724 if (strcmp(descriptor, "Ljava/lang/Object;") == 0) { 1725 klass.Assign(GetClassRoot(kJavaLangObject)); 1726 } else if (strcmp(descriptor, "Ljava/lang/Class;") == 0) { 1727 klass.Assign(GetClassRoot(kJavaLangClass)); 1728 } else if (strcmp(descriptor, "Ljava/lang/String;") == 0) { 1729 klass.Assign(GetClassRoot(kJavaLangString)); 1730 } else if (strcmp(descriptor, "Ljava/lang/ref/Reference;") == 0) { 1731 klass.Assign(GetClassRoot(kJavaLangRefReference)); 1732 } else if (strcmp(descriptor, "Ljava/lang/DexCache;") == 0) { 1733 klass.Assign(GetClassRoot(kJavaLangDexCache)); 1734 } else if (strcmp(descriptor, "Ljava/lang/reflect/ArtMethod;") == 0) { 1735 klass.Assign(GetClassRoot(kJavaLangReflectArtMethod)); 1736 } 1737 } 1738 1739 if (klass.Get() == nullptr) { 1740 // Allocate a class with the status of not ready. 1741 // Interface object should get the right size here. Regular class will 1742 // figure out the right size later and be replaced with one of the right 1743 // size when the class becomes resolved. 1744 klass.Assign(AllocClass(self, SizeOfClassWithoutEmbeddedTables(dex_file, dex_class_def))); 1745 } 1746 if (UNLIKELY(klass.Get() == nullptr)) { 1747 CHECK(self->IsExceptionPending()); // Expect an OOME. 1748 return nullptr; 1749 } 1750 klass->SetDexCache(FindDexCache(dex_file)); 1751 1752 SetupClass(dex_file, dex_class_def, klass, class_loader.Get()); 1753 1754 // Mark the string class by setting its access flag. 1755 if (UNLIKELY(!init_done_)) { 1756 if (strcmp(descriptor, "Ljava/lang/String;") == 0) { 1757 klass->SetStringClass(); 1758 } 1759 } 1760 1761 ObjectLock<mirror::Class> lock(self, klass); 1762 klass->SetClinitThreadId(self->GetTid()); 1763 1764 // Add the newly loaded class to the loaded classes table. 1765 mirror::Class* existing = InsertClass(descriptor, klass.Get(), hash); 1766 if (existing != nullptr) { 1767 // We failed to insert because we raced with another thread. Calling EnsureResolved may cause 1768 // this thread to block. 1769 return EnsureResolved(self, descriptor, existing); 1770 } 1771 1772 // Load the fields and other things after we are inserted in the table. This is so that we don't 1773 // end up allocating unfree-able linear alloc resources and then lose the race condition. The 1774 // other reason is that the field roots are only visited from the class table. So we need to be 1775 // inserted before we allocate / fill in these fields. 1776 LoadClass(self, dex_file, dex_class_def, klass); 1777 if (self->IsExceptionPending()) { 1778 // An exception occured during load, set status to erroneous while holding klass' lock in case 1779 // notification is necessary. 1780 if (!klass->IsErroneous()) { 1781 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 1782 } 1783 return nullptr; 1784 } 1785 1786 // Finish loading (if necessary) by finding parents 1787 CHECK(!klass->IsLoaded()); 1788 if (!LoadSuperAndInterfaces(klass, dex_file)) { 1789 // Loading failed. 1790 if (!klass->IsErroneous()) { 1791 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 1792 } 1793 return nullptr; 1794 } 1795 CHECK(klass->IsLoaded()); 1796 // Link the class (if necessary) 1797 CHECK(!klass->IsResolved()); 1798 // TODO: Use fast jobjects? 1799 auto interfaces = hs.NewHandle<mirror::ObjectArray<mirror::Class>>(nullptr); 1800 1801 mirror::Class* new_class = nullptr; 1802 if (!LinkClass(self, descriptor, klass, interfaces, &new_class)) { 1803 // Linking failed. 1804 if (!klass->IsErroneous()) { 1805 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 1806 } 1807 return nullptr; 1808 } 1809 self->AssertNoPendingException(); 1810 CHECK(new_class != nullptr) << descriptor; 1811 CHECK(new_class->IsResolved()) << descriptor; 1812 1813 Handle<mirror::Class> new_class_h(hs.NewHandle(new_class)); 1814 1815 // Instrumentation may have updated entrypoints for all methods of all 1816 // classes. However it could not update methods of this class while we 1817 // were loading it. Now the class is resolved, we can update entrypoints 1818 // as required by instrumentation. 1819 if (Runtime::Current()->GetInstrumentation()->AreExitStubsInstalled()) { 1820 // We must be in the kRunnable state to prevent instrumentation from 1821 // suspending all threads to update entrypoints while we are doing it 1822 // for this class. 1823 DCHECK_EQ(self->GetState(), kRunnable); 1824 Runtime::Current()->GetInstrumentation()->InstallStubsForClass(new_class_h.Get()); 1825 } 1826 1827 /* 1828 * We send CLASS_PREPARE events to the debugger from here. The 1829 * definition of "preparation" is creating the static fields for a 1830 * class and initializing them to the standard default values, but not 1831 * executing any code (that comes later, during "initialization"). 1832 * 1833 * We did the static preparation in LinkClass. 1834 * 1835 * The class has been prepared and resolved but possibly not yet verified 1836 * at this point. 1837 */ 1838 Dbg::PostClassPrepare(new_class_h.Get()); 1839 1840 return new_class_h.Get(); 1841} 1842 1843uint32_t ClassLinker::SizeOfClassWithoutEmbeddedTables(const DexFile& dex_file, 1844 const DexFile::ClassDef& dex_class_def) { 1845 const uint8_t* class_data = dex_file.GetClassData(dex_class_def); 1846 size_t num_ref = 0; 1847 size_t num_8 = 0; 1848 size_t num_16 = 0; 1849 size_t num_32 = 0; 1850 size_t num_64 = 0; 1851 if (class_data != nullptr) { 1852 for (ClassDataItemIterator it(dex_file, class_data); it.HasNextStaticField(); it.Next()) { 1853 const DexFile::FieldId& field_id = dex_file.GetFieldId(it.GetMemberIndex()); 1854 const char* descriptor = dex_file.GetFieldTypeDescriptor(field_id); 1855 char c = descriptor[0]; 1856 switch (c) { 1857 case 'L': 1858 case '[': 1859 num_ref++; 1860 break; 1861 case 'J': 1862 case 'D': 1863 num_64++; 1864 break; 1865 case 'I': 1866 case 'F': 1867 num_32++; 1868 break; 1869 case 'S': 1870 case 'C': 1871 num_16++; 1872 break; 1873 case 'B': 1874 case 'Z': 1875 num_8++; 1876 break; 1877 default: 1878 LOG(FATAL) << "Unknown descriptor: " << c; 1879 UNREACHABLE(); 1880 } 1881 } 1882 } 1883 return mirror::Class::ComputeClassSize(false, 0, num_8, num_16, num_32, num_64, num_ref); 1884} 1885 1886OatFile::OatClass ClassLinker::FindOatClass(const DexFile& dex_file, uint16_t class_def_idx, 1887 bool* found) { 1888 DCHECK_NE(class_def_idx, DexFile::kDexNoIndex16); 1889 const OatFile::OatDexFile* oat_dex_file = dex_file.GetOatDexFile(); 1890 if (oat_dex_file == nullptr) { 1891 *found = false; 1892 return OatFile::OatClass::Invalid(); 1893 } 1894 *found = true; 1895 return oat_dex_file->GetOatClass(class_def_idx); 1896} 1897 1898static uint32_t GetOatMethodIndexFromMethodIndex(const DexFile& dex_file, uint16_t class_def_idx, 1899 uint32_t method_idx) { 1900 const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_idx); 1901 const uint8_t* class_data = dex_file.GetClassData(class_def); 1902 CHECK(class_data != nullptr); 1903 ClassDataItemIterator it(dex_file, class_data); 1904 // Skip fields 1905 while (it.HasNextStaticField()) { 1906 it.Next(); 1907 } 1908 while (it.HasNextInstanceField()) { 1909 it.Next(); 1910 } 1911 // Process methods 1912 size_t class_def_method_index = 0; 1913 while (it.HasNextDirectMethod()) { 1914 if (it.GetMemberIndex() == method_idx) { 1915 return class_def_method_index; 1916 } 1917 class_def_method_index++; 1918 it.Next(); 1919 } 1920 while (it.HasNextVirtualMethod()) { 1921 if (it.GetMemberIndex() == method_idx) { 1922 return class_def_method_index; 1923 } 1924 class_def_method_index++; 1925 it.Next(); 1926 } 1927 DCHECK(!it.HasNext()); 1928 LOG(FATAL) << "Failed to find method index " << method_idx << " in " << dex_file.GetLocation(); 1929 UNREACHABLE(); 1930} 1931 1932const OatFile::OatMethod ClassLinker::FindOatMethodFor(mirror::ArtMethod* method, bool* found) { 1933 // Although we overwrite the trampoline of non-static methods, we may get here via the resolution 1934 // method for direct methods (or virtual methods made direct). 1935 mirror::Class* declaring_class = method->GetDeclaringClass(); 1936 size_t oat_method_index; 1937 if (method->IsStatic() || method->IsDirect()) { 1938 // Simple case where the oat method index was stashed at load time. 1939 oat_method_index = method->GetMethodIndex(); 1940 } else { 1941 // We're invoking a virtual method directly (thanks to sharpening), compute the oat_method_index 1942 // by search for its position in the declared virtual methods. 1943 oat_method_index = declaring_class->NumDirectMethods(); 1944 size_t end = declaring_class->NumVirtualMethods(); 1945 bool found_virtual = false; 1946 for (size_t i = 0; i < end; i++) { 1947 // Check method index instead of identity in case of duplicate method definitions. 1948 if (method->GetDexMethodIndex() == 1949 declaring_class->GetVirtualMethod(i)->GetDexMethodIndex()) { 1950 found_virtual = true; 1951 break; 1952 } 1953 oat_method_index++; 1954 } 1955 CHECK(found_virtual) << "Didn't find oat method index for virtual method: " 1956 << PrettyMethod(method); 1957 } 1958 DCHECK_EQ(oat_method_index, 1959 GetOatMethodIndexFromMethodIndex(*declaring_class->GetDexCache()->GetDexFile(), 1960 method->GetDeclaringClass()->GetDexClassDefIndex(), 1961 method->GetDexMethodIndex())); 1962 OatFile::OatClass oat_class = FindOatClass(*declaring_class->GetDexCache()->GetDexFile(), 1963 declaring_class->GetDexClassDefIndex(), 1964 found); 1965 if (!(*found)) { 1966 return OatFile::OatMethod::Invalid(); 1967 } 1968 return oat_class.GetOatMethod(oat_method_index); 1969} 1970 1971// Special case to get oat code without overwriting a trampoline. 1972const void* ClassLinker::GetQuickOatCodeFor(mirror::ArtMethod* method) { 1973 CHECK(!method->IsAbstract()) << PrettyMethod(method); 1974 if (method->IsProxyMethod()) { 1975 return GetQuickProxyInvokeHandler(); 1976 } 1977 bool found; 1978 OatFile::OatMethod oat_method = FindOatMethodFor(method, &found); 1979 if (found) { 1980 auto* code = oat_method.GetQuickCode(); 1981 if (code != nullptr) { 1982 return code; 1983 } 1984 } 1985 jit::Jit* const jit = Runtime::Current()->GetJit(); 1986 if (jit != nullptr) { 1987 auto* code = jit->GetCodeCache()->GetCodeFor(method); 1988 if (code != nullptr) { 1989 return code; 1990 } 1991 } 1992 if (method->IsNative()) { 1993 // No code and native? Use generic trampoline. 1994 return GetQuickGenericJniStub(); 1995 } 1996 return GetQuickToInterpreterBridge(); 1997} 1998 1999const void* ClassLinker::GetOatMethodQuickCodeFor(mirror::ArtMethod* method) { 2000 if (method->IsNative() || method->IsAbstract() || method->IsProxyMethod()) { 2001 return nullptr; 2002 } 2003 bool found; 2004 OatFile::OatMethod oat_method = FindOatMethodFor(method, &found); 2005 if (found) { 2006 return oat_method.GetQuickCode(); 2007 } 2008 jit::Jit* jit = Runtime::Current()->GetJit(); 2009 if (jit != nullptr) { 2010 auto* code = jit->GetCodeCache()->GetCodeFor(method); 2011 if (code != nullptr) { 2012 return code; 2013 } 2014 } 2015 return nullptr; 2016} 2017 2018const void* ClassLinker::GetQuickOatCodeFor(const DexFile& dex_file, uint16_t class_def_idx, 2019 uint32_t method_idx) { 2020 bool found; 2021 OatFile::OatClass oat_class = FindOatClass(dex_file, class_def_idx, &found); 2022 if (!found) { 2023 return nullptr; 2024 } 2025 uint32_t oat_method_idx = GetOatMethodIndexFromMethodIndex(dex_file, class_def_idx, method_idx); 2026 return oat_class.GetOatMethod(oat_method_idx).GetQuickCode(); 2027} 2028 2029// Returns true if the method must run with interpreter, false otherwise. 2030static bool NeedsInterpreter(mirror::ArtMethod* method, const void* quick_code) 2031 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 2032 if (quick_code == nullptr) { 2033 // No code: need interpreter. 2034 // May return true for native code, in the case of generic JNI 2035 // DCHECK(!method->IsNative()); 2036 return true; 2037 } 2038 // If interpreter mode is enabled, every method (except native and proxy) must 2039 // be run with interpreter. 2040 return Runtime::Current()->GetInstrumentation()->InterpretOnly() && 2041 !method->IsNative() && !method->IsProxyMethod(); 2042} 2043 2044void ClassLinker::FixupStaticTrampolines(mirror::Class* klass) { 2045 DCHECK(klass->IsInitialized()) << PrettyDescriptor(klass); 2046 if (klass->NumDirectMethods() == 0) { 2047 return; // No direct methods => no static methods. 2048 } 2049 Runtime* runtime = Runtime::Current(); 2050 if (!runtime->IsStarted()) { 2051 if (runtime->IsAotCompiler() || runtime->GetHeap()->HasImageSpace()) { 2052 return; // OAT file unavailable. 2053 } 2054 } 2055 2056 const DexFile& dex_file = klass->GetDexFile(); 2057 const DexFile::ClassDef* dex_class_def = klass->GetClassDef(); 2058 CHECK(dex_class_def != nullptr); 2059 const uint8_t* class_data = dex_file.GetClassData(*dex_class_def); 2060 // There should always be class data if there were direct methods. 2061 CHECK(class_data != nullptr) << PrettyDescriptor(klass); 2062 ClassDataItemIterator it(dex_file, class_data); 2063 // Skip fields 2064 while (it.HasNextStaticField()) { 2065 it.Next(); 2066 } 2067 while (it.HasNextInstanceField()) { 2068 it.Next(); 2069 } 2070 bool has_oat_class; 2071 OatFile::OatClass oat_class = FindOatClass(dex_file, klass->GetDexClassDefIndex(), 2072 &has_oat_class); 2073 // Link the code of methods skipped by LinkCode. 2074 for (size_t method_index = 0; it.HasNextDirectMethod(); ++method_index, it.Next()) { 2075 mirror::ArtMethod* method = klass->GetDirectMethod(method_index); 2076 if (!method->IsStatic()) { 2077 // Only update static methods. 2078 continue; 2079 } 2080 const void* quick_code = nullptr; 2081 if (has_oat_class) { 2082 OatFile::OatMethod oat_method = oat_class.GetOatMethod(method_index); 2083 quick_code = oat_method.GetQuickCode(); 2084 } 2085 const bool enter_interpreter = NeedsInterpreter(method, quick_code); 2086 if (enter_interpreter) { 2087 // Use interpreter entry point. 2088 // Check whether the method is native, in which case it's generic JNI. 2089 if (quick_code == nullptr && method->IsNative()) { 2090 quick_code = GetQuickGenericJniStub(); 2091 } else { 2092 quick_code = GetQuickToInterpreterBridge(); 2093 } 2094 } 2095 runtime->GetInstrumentation()->UpdateMethodsCode(method, quick_code); 2096 } 2097 // Ignore virtual methods on the iterator. 2098} 2099 2100void ClassLinker::LinkCode(Handle<mirror::ArtMethod> method, 2101 const OatFile::OatClass* oat_class, 2102 uint32_t class_def_method_index) { 2103 Runtime* runtime = Runtime::Current(); 2104 if (runtime->IsAotCompiler()) { 2105 // The following code only applies to a non-compiler runtime. 2106 return; 2107 } 2108 // Method shouldn't have already been linked. 2109 DCHECK(method->GetEntryPointFromQuickCompiledCode() == nullptr); 2110 if (oat_class != nullptr) { 2111 // Every kind of method should at least get an invoke stub from the oat_method. 2112 // non-abstract methods also get their code pointers. 2113 const OatFile::OatMethod oat_method = oat_class->GetOatMethod(class_def_method_index); 2114 oat_method.LinkMethod(method.Get()); 2115 } 2116 2117 // Install entry point from interpreter. 2118 bool enter_interpreter = NeedsInterpreter(method.Get(), 2119 method->GetEntryPointFromQuickCompiledCode()); 2120 if (enter_interpreter && !method->IsNative()) { 2121 method->SetEntryPointFromInterpreter(artInterpreterToInterpreterBridge); 2122 } else { 2123 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 2124 } 2125 2126 if (method->IsAbstract()) { 2127 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge()); 2128 return; 2129 } 2130 2131 if (method->IsStatic() && !method->IsConstructor()) { 2132 // For static methods excluding the class initializer, install the trampoline. 2133 // It will be replaced by the proper entry point by ClassLinker::FixupStaticTrampolines 2134 // after initializing class (see ClassLinker::InitializeClass method). 2135 method->SetEntryPointFromQuickCompiledCode(GetQuickResolutionStub()); 2136 } else if (enter_interpreter) { 2137 if (!method->IsNative()) { 2138 // Set entry point from compiled code if there's no code or in interpreter only mode. 2139 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge()); 2140 } else { 2141 method->SetEntryPointFromQuickCompiledCode(GetQuickGenericJniStub()); 2142 } 2143 } 2144 2145 if (method->IsNative()) { 2146 // Unregistering restores the dlsym lookup stub. 2147 method->UnregisterNative(); 2148 2149 if (enter_interpreter) { 2150 // We have a native method here without code. Then it should have either the generic JNI 2151 // trampoline as entrypoint (non-static), or the resolution trampoline (static). 2152 // TODO: this doesn't handle all the cases where trampolines may be installed. 2153 const void* entry_point = method->GetEntryPointFromQuickCompiledCode(); 2154 DCHECK(IsQuickGenericJniStub(entry_point) || IsQuickResolutionStub(entry_point)); 2155 } 2156 } 2157} 2158 2159void ClassLinker::SetupClass(const DexFile& dex_file, const DexFile::ClassDef& dex_class_def, 2160 Handle<mirror::Class> klass, mirror::ClassLoader* class_loader) { 2161 CHECK(klass.Get() != nullptr); 2162 CHECK(klass->GetDexCache() != nullptr); 2163 CHECK_EQ(mirror::Class::kStatusNotReady, klass->GetStatus()); 2164 const char* descriptor = dex_file.GetClassDescriptor(dex_class_def); 2165 CHECK(descriptor != nullptr); 2166 2167 klass->SetClass(GetClassRoot(kJavaLangClass)); 2168 uint32_t access_flags = dex_class_def.GetJavaAccessFlags(); 2169 CHECK_EQ(access_flags & ~kAccJavaFlagsMask, 0U); 2170 klass->SetAccessFlags(access_flags); 2171 klass->SetClassLoader(class_loader); 2172 DCHECK_EQ(klass->GetPrimitiveType(), Primitive::kPrimNot); 2173 mirror::Class::SetStatus(klass, mirror::Class::kStatusIdx, nullptr); 2174 2175 klass->SetDexClassDefIndex(dex_file.GetIndexForClassDef(dex_class_def)); 2176 klass->SetDexTypeIndex(dex_class_def.class_idx_); 2177 CHECK(klass->GetDexCacheStrings() != nullptr); 2178} 2179 2180void ClassLinker::LoadClass(Thread* self, const DexFile& dex_file, 2181 const DexFile::ClassDef& dex_class_def, 2182 Handle<mirror::Class> klass) { 2183 const uint8_t* class_data = dex_file.GetClassData(dex_class_def); 2184 if (class_data == nullptr) { 2185 return; // no fields or methods - for example a marker interface 2186 } 2187 bool has_oat_class = false; 2188 if (Runtime::Current()->IsStarted() && !Runtime::Current()->IsAotCompiler()) { 2189 OatFile::OatClass oat_class = FindOatClass(dex_file, klass->GetDexClassDefIndex(), 2190 &has_oat_class); 2191 if (has_oat_class) { 2192 LoadClassMembers(self, dex_file, class_data, klass, &oat_class); 2193 } 2194 } 2195 if (!has_oat_class) { 2196 LoadClassMembers(self, dex_file, class_data, klass, nullptr); 2197 } 2198} 2199 2200ArtField* ClassLinker::AllocArtFieldArray(Thread* self, size_t length) { 2201 auto* const la = Runtime::Current()->GetLinearAlloc(); 2202 auto* ptr = reinterpret_cast<ArtField*>(la->AllocArray<ArtField>(self, length)); 2203 CHECK(ptr!= nullptr); 2204 std::uninitialized_fill_n(ptr, length, ArtField()); 2205 return ptr; 2206} 2207 2208void ClassLinker::LoadClassMembers(Thread* self, const DexFile& dex_file, 2209 const uint8_t* class_data, 2210 Handle<mirror::Class> klass, 2211 const OatFile::OatClass* oat_class) { 2212 // Load static fields. 2213 ClassDataItemIterator it(dex_file, class_data); 2214 const size_t num_sfields = it.NumStaticFields(); 2215 ArtField* sfields = num_sfields != 0 ? AllocArtFieldArray(self, num_sfields) : nullptr; 2216 for (size_t i = 0; it.HasNextStaticField(); i++, it.Next()) { 2217 CHECK_LT(i, num_sfields); 2218 LoadField(it, klass, &sfields[i]); 2219 } 2220 klass->SetSFields(sfields); 2221 klass->SetNumStaticFields(num_sfields); 2222 DCHECK_EQ(klass->NumStaticFields(), num_sfields); 2223 // Load instance fields. 2224 const size_t num_ifields = it.NumInstanceFields(); 2225 ArtField* ifields = num_ifields != 0 ? AllocArtFieldArray(self, num_ifields) : nullptr; 2226 for (size_t i = 0; it.HasNextInstanceField(); i++, it.Next()) { 2227 CHECK_LT(i, num_ifields); 2228 LoadField(it, klass, &ifields[i]); 2229 } 2230 klass->SetIFields(ifields); 2231 klass->SetNumInstanceFields(num_ifields); 2232 DCHECK_EQ(klass->NumInstanceFields(), num_ifields); 2233 // Note: We cannot have thread suspension until the field arrays are setup or else 2234 // Class::VisitFieldRoots may miss some fields. 2235 self->AllowThreadSuspension(); 2236 // Load methods. 2237 if (it.NumDirectMethods() != 0) { 2238 // TODO: append direct methods to class object 2239 mirror::ObjectArray<mirror::ArtMethod>* directs = 2240 AllocArtMethodArray(self, it.NumDirectMethods()); 2241 if (UNLIKELY(directs == nullptr)) { 2242 CHECK(self->IsExceptionPending()); // OOME. 2243 return; 2244 } 2245 klass->SetDirectMethods(directs); 2246 } 2247 if (it.NumVirtualMethods() != 0) { 2248 // TODO: append direct methods to class object 2249 mirror::ObjectArray<mirror::ArtMethod>* virtuals = 2250 AllocArtMethodArray(self, it.NumVirtualMethods()); 2251 if (UNLIKELY(virtuals == nullptr)) { 2252 CHECK(self->IsExceptionPending()); // OOME. 2253 return; 2254 } 2255 klass->SetVirtualMethods(virtuals); 2256 } 2257 size_t class_def_method_index = 0; 2258 uint32_t last_dex_method_index = DexFile::kDexNoIndex; 2259 size_t last_class_def_method_index = 0; 2260 for (size_t i = 0; it.HasNextDirectMethod(); i++, it.Next()) { 2261 self->AllowThreadSuspension(); 2262 StackHandleScope<1> hs(self); 2263 Handle<mirror::ArtMethod> method(hs.NewHandle(LoadMethod(self, dex_file, it, klass))); 2264 if (UNLIKELY(method.Get() == nullptr)) { 2265 CHECK(self->IsExceptionPending()); // OOME. 2266 return; 2267 } 2268 klass->SetDirectMethod(i, method.Get()); 2269 LinkCode(method, oat_class, class_def_method_index); 2270 uint32_t it_method_index = it.GetMemberIndex(); 2271 if (last_dex_method_index == it_method_index) { 2272 // duplicate case 2273 method->SetMethodIndex(last_class_def_method_index); 2274 } else { 2275 method->SetMethodIndex(class_def_method_index); 2276 last_dex_method_index = it_method_index; 2277 last_class_def_method_index = class_def_method_index; 2278 } 2279 class_def_method_index++; 2280 } 2281 for (size_t i = 0; it.HasNextVirtualMethod(); i++, it.Next()) { 2282 self->AllowThreadSuspension(); 2283 StackHandleScope<1> hs(self); 2284 Handle<mirror::ArtMethod> method(hs.NewHandle(LoadMethod(self, dex_file, it, klass))); 2285 if (UNLIKELY(method.Get() == nullptr)) { 2286 CHECK(self->IsExceptionPending()); // OOME. 2287 return; 2288 } 2289 klass->SetVirtualMethod(i, method.Get()); 2290 DCHECK_EQ(class_def_method_index, it.NumDirectMethods() + i); 2291 LinkCode(method, oat_class, class_def_method_index); 2292 class_def_method_index++; 2293 } 2294 DCHECK(!it.HasNext()); 2295} 2296 2297void ClassLinker::LoadField(const ClassDataItemIterator& it, Handle<mirror::Class> klass, 2298 ArtField* dst) { 2299 const uint32_t field_idx = it.GetMemberIndex(); 2300 dst->SetDexFieldIndex(field_idx); 2301 dst->SetDeclaringClass(klass.Get()); 2302 dst->SetAccessFlags(it.GetFieldAccessFlags()); 2303} 2304 2305mirror::ArtMethod* ClassLinker::LoadMethod(Thread* self, const DexFile& dex_file, 2306 const ClassDataItemIterator& it, 2307 Handle<mirror::Class> klass) { 2308 uint32_t dex_method_idx = it.GetMemberIndex(); 2309 const DexFile::MethodId& method_id = dex_file.GetMethodId(dex_method_idx); 2310 const char* method_name = dex_file.StringDataByIdx(method_id.name_idx_); 2311 2312 mirror::ArtMethod* dst = AllocArtMethod(self); 2313 if (UNLIKELY(dst == nullptr)) { 2314 CHECK(self->IsExceptionPending()); // OOME. 2315 return nullptr; 2316 } 2317 DCHECK(dst->IsArtMethod()) << PrettyDescriptor(dst->GetClass()); 2318 2319 ScopedAssertNoThreadSuspension ants(self, "LoadMethod"); 2320 dst->SetDexMethodIndex(dex_method_idx); 2321 dst->SetDeclaringClass(klass.Get()); 2322 dst->SetCodeItemOffset(it.GetMethodCodeItemOffset()); 2323 2324 dst->SetDexCacheResolvedMethods(klass->GetDexCache()->GetResolvedMethods()); 2325 dst->SetDexCacheResolvedTypes(klass->GetDexCache()->GetResolvedTypes()); 2326 2327 uint32_t access_flags = it.GetMethodAccessFlags(); 2328 2329 if (UNLIKELY(strcmp("finalize", method_name) == 0)) { 2330 // Set finalizable flag on declaring class. 2331 if (strcmp("V", dex_file.GetShorty(method_id.proto_idx_)) == 0) { 2332 // Void return type. 2333 if (klass->GetClassLoader() != nullptr) { // All non-boot finalizer methods are flagged. 2334 klass->SetFinalizable(); 2335 } else { 2336 std::string temp; 2337 const char* klass_descriptor = klass->GetDescriptor(&temp); 2338 // The Enum class declares a "final" finalize() method to prevent subclasses from 2339 // introducing a finalizer. We don't want to set the finalizable flag for Enum or its 2340 // subclasses, so we exclude it here. 2341 // We also want to avoid setting the flag on Object, where we know that finalize() is 2342 // empty. 2343 if (strcmp(klass_descriptor, "Ljava/lang/Object;") != 0 && 2344 strcmp(klass_descriptor, "Ljava/lang/Enum;") != 0) { 2345 klass->SetFinalizable(); 2346 } 2347 } 2348 } 2349 } else if (method_name[0] == '<') { 2350 // Fix broken access flags for initializers. Bug 11157540. 2351 bool is_init = (strcmp("<init>", method_name) == 0); 2352 bool is_clinit = !is_init && (strcmp("<clinit>", method_name) == 0); 2353 if (UNLIKELY(!is_init && !is_clinit)) { 2354 LOG(WARNING) << "Unexpected '<' at start of method name " << method_name; 2355 } else { 2356 if (UNLIKELY((access_flags & kAccConstructor) == 0)) { 2357 LOG(WARNING) << method_name << " didn't have expected constructor access flag in class " 2358 << PrettyDescriptor(klass.Get()) << " in dex file " << dex_file.GetLocation(); 2359 access_flags |= kAccConstructor; 2360 } 2361 } 2362 } 2363 dst->SetAccessFlags(access_flags); 2364 2365 return dst; 2366} 2367 2368void ClassLinker::AppendToBootClassPath(Thread* self, const DexFile& dex_file) { 2369 StackHandleScope<1> hs(self); 2370 Handle<mirror::DexCache> dex_cache(hs.NewHandle(AllocDexCache(self, dex_file))); 2371 CHECK(dex_cache.Get() != nullptr) << "Failed to allocate dex cache for " 2372 << dex_file.GetLocation(); 2373 AppendToBootClassPath(dex_file, dex_cache); 2374} 2375 2376void ClassLinker::AppendToBootClassPath(const DexFile& dex_file, 2377 Handle<mirror::DexCache> dex_cache) { 2378 CHECK(dex_cache.Get() != nullptr) << dex_file.GetLocation(); 2379 boot_class_path_.push_back(&dex_file); 2380 RegisterDexFile(dex_file, dex_cache); 2381} 2382 2383bool ClassLinker::IsDexFileRegisteredLocked(const DexFile& dex_file) { 2384 dex_lock_.AssertSharedHeld(Thread::Current()); 2385 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2386 mirror::DexCache* dex_cache = GetDexCache(i); 2387 if (dex_cache->GetDexFile() == &dex_file) { 2388 return true; 2389 } 2390 } 2391 return false; 2392} 2393 2394bool ClassLinker::IsDexFileRegistered(const DexFile& dex_file) { 2395 ReaderMutexLock mu(Thread::Current(), dex_lock_); 2396 return IsDexFileRegisteredLocked(dex_file); 2397} 2398 2399void ClassLinker::RegisterDexFileLocked(const DexFile& dex_file, 2400 Handle<mirror::DexCache> dex_cache) { 2401 dex_lock_.AssertExclusiveHeld(Thread::Current()); 2402 CHECK(dex_cache.Get() != nullptr) << dex_file.GetLocation(); 2403 CHECK(dex_cache->GetLocation()->Equals(dex_file.GetLocation())) 2404 << dex_cache->GetLocation()->ToModifiedUtf8() << " " << dex_file.GetLocation(); 2405 dex_caches_.push_back(GcRoot<mirror::DexCache>(dex_cache.Get())); 2406 dex_cache->SetDexFile(&dex_file); 2407 if (log_new_dex_caches_roots_) { 2408 // TODO: This is not safe if we can remove dex caches. 2409 new_dex_cache_roots_.push_back(dex_caches_.size() - 1); 2410 } 2411} 2412 2413void ClassLinker::RegisterDexFile(const DexFile& dex_file) { 2414 Thread* self = Thread::Current(); 2415 { 2416 ReaderMutexLock mu(self, dex_lock_); 2417 if (IsDexFileRegisteredLocked(dex_file)) { 2418 return; 2419 } 2420 } 2421 // Don't alloc while holding the lock, since allocation may need to 2422 // suspend all threads and another thread may need the dex_lock_ to 2423 // get to a suspend point. 2424 StackHandleScope<1> hs(self); 2425 Handle<mirror::DexCache> dex_cache(hs.NewHandle(AllocDexCache(self, dex_file))); 2426 CHECK(dex_cache.Get() != nullptr) << "Failed to allocate dex cache for " 2427 << dex_file.GetLocation(); 2428 { 2429 WriterMutexLock mu(self, dex_lock_); 2430 if (IsDexFileRegisteredLocked(dex_file)) { 2431 return; 2432 } 2433 RegisterDexFileLocked(dex_file, dex_cache); 2434 } 2435} 2436 2437void ClassLinker::RegisterDexFile(const DexFile& dex_file, 2438 Handle<mirror::DexCache> dex_cache) { 2439 WriterMutexLock mu(Thread::Current(), dex_lock_); 2440 RegisterDexFileLocked(dex_file, dex_cache); 2441} 2442 2443mirror::DexCache* ClassLinker::FindDexCache(const DexFile& dex_file) { 2444 ReaderMutexLock mu(Thread::Current(), dex_lock_); 2445 // Search assuming unique-ness of dex file. 2446 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2447 mirror::DexCache* dex_cache = GetDexCache(i); 2448 if (dex_cache->GetDexFile() == &dex_file) { 2449 return dex_cache; 2450 } 2451 } 2452 // Search matching by location name. 2453 std::string location(dex_file.GetLocation()); 2454 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2455 mirror::DexCache* dex_cache = GetDexCache(i); 2456 if (dex_cache->GetDexFile()->GetLocation() == location) { 2457 return dex_cache; 2458 } 2459 } 2460 // Failure, dump diagnostic and abort. 2461 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2462 mirror::DexCache* dex_cache = GetDexCache(i); 2463 LOG(ERROR) << "Registered dex file " << i << " = " << dex_cache->GetDexFile()->GetLocation(); 2464 } 2465 LOG(FATAL) << "Failed to find DexCache for DexFile " << location; 2466 UNREACHABLE(); 2467} 2468 2469void ClassLinker::FixupDexCaches(mirror::ArtMethod* resolution_method) { 2470 ReaderMutexLock mu(Thread::Current(), dex_lock_); 2471 for (size_t i = 0; i != dex_caches_.size(); ++i) { 2472 mirror::DexCache* dex_cache = GetDexCache(i); 2473 dex_cache->Fixup(resolution_method); 2474 } 2475} 2476 2477mirror::Class* ClassLinker::CreatePrimitiveClass(Thread* self, Primitive::Type type) { 2478 mirror::Class* klass = AllocClass(self, mirror::Class::PrimitiveClassSize()); 2479 if (UNLIKELY(klass == nullptr)) { 2480 return nullptr; 2481 } 2482 return InitializePrimitiveClass(klass, type); 2483} 2484 2485mirror::Class* ClassLinker::InitializePrimitiveClass(mirror::Class* primitive_class, 2486 Primitive::Type type) { 2487 CHECK(primitive_class != nullptr); 2488 // Must hold lock on object when initializing. 2489 Thread* self = Thread::Current(); 2490 StackHandleScope<1> hs(self); 2491 Handle<mirror::Class> h_class(hs.NewHandle(primitive_class)); 2492 ObjectLock<mirror::Class> lock(self, h_class); 2493 h_class->SetAccessFlags(kAccPublic | kAccFinal | kAccAbstract); 2494 h_class->SetPrimitiveType(type); 2495 mirror::Class::SetStatus(h_class, mirror::Class::kStatusInitialized, self); 2496 const char* descriptor = Primitive::Descriptor(type); 2497 mirror::Class* existing = InsertClass(descriptor, h_class.Get(), 2498 ComputeModifiedUtf8Hash(descriptor)); 2499 CHECK(existing == nullptr) << "InitPrimitiveClass(" << type << ") failed"; 2500 return h_class.Get(); 2501} 2502 2503// Create an array class (i.e. the class object for the array, not the 2504// array itself). "descriptor" looks like "[C" or "[[[[B" or 2505// "[Ljava/lang/String;". 2506// 2507// If "descriptor" refers to an array of primitives, look up the 2508// primitive type's internally-generated class object. 2509// 2510// "class_loader" is the class loader of the class that's referring to 2511// us. It's used to ensure that we're looking for the element type in 2512// the right context. It does NOT become the class loader for the 2513// array class; that always comes from the base element class. 2514// 2515// Returns null with an exception raised on failure. 2516mirror::Class* ClassLinker::CreateArrayClass(Thread* self, const char* descriptor, size_t hash, 2517 Handle<mirror::ClassLoader> class_loader) { 2518 // Identify the underlying component type 2519 CHECK_EQ('[', descriptor[0]); 2520 StackHandleScope<2> hs(self); 2521 MutableHandle<mirror::Class> component_type(hs.NewHandle(FindClass(self, descriptor + 1, 2522 class_loader))); 2523 if (component_type.Get() == nullptr) { 2524 DCHECK(self->IsExceptionPending()); 2525 // We need to accept erroneous classes as component types. 2526 const size_t component_hash = ComputeModifiedUtf8Hash(descriptor + 1); 2527 component_type.Assign(LookupClass(self, descriptor + 1, component_hash, class_loader.Get())); 2528 if (component_type.Get() == nullptr) { 2529 DCHECK(self->IsExceptionPending()); 2530 return nullptr; 2531 } else { 2532 self->ClearException(); 2533 } 2534 } 2535 if (UNLIKELY(component_type->IsPrimitiveVoid())) { 2536 ThrowNoClassDefFoundError("Attempt to create array of void primitive type"); 2537 return nullptr; 2538 } 2539 // See if the component type is already loaded. Array classes are 2540 // always associated with the class loader of their underlying 2541 // element type -- an array of Strings goes with the loader for 2542 // java/lang/String -- so we need to look for it there. (The 2543 // caller should have checked for the existence of the class 2544 // before calling here, but they did so with *their* class loader, 2545 // not the component type's loader.) 2546 // 2547 // If we find it, the caller adds "loader" to the class' initiating 2548 // loader list, which should prevent us from going through this again. 2549 // 2550 // This call is unnecessary if "loader" and "component_type->GetClassLoader()" 2551 // are the same, because our caller (FindClass) just did the 2552 // lookup. (Even if we get this wrong we still have correct behavior, 2553 // because we effectively do this lookup again when we add the new 2554 // class to the hash table --- necessary because of possible races with 2555 // other threads.) 2556 if (class_loader.Get() != component_type->GetClassLoader()) { 2557 mirror::Class* new_class = LookupClass(self, descriptor, hash, component_type->GetClassLoader()); 2558 if (new_class != nullptr) { 2559 return new_class; 2560 } 2561 } 2562 2563 // Fill out the fields in the Class. 2564 // 2565 // It is possible to execute some methods against arrays, because 2566 // all arrays are subclasses of java_lang_Object_, so we need to set 2567 // up a vtable. We can just point at the one in java_lang_Object_. 2568 // 2569 // Array classes are simple enough that we don't need to do a full 2570 // link step. 2571 auto new_class = hs.NewHandle<mirror::Class>(nullptr); 2572 if (UNLIKELY(!init_done_)) { 2573 // Classes that were hand created, ie not by FindSystemClass 2574 if (strcmp(descriptor, "[Ljava/lang/Class;") == 0) { 2575 new_class.Assign(GetClassRoot(kClassArrayClass)); 2576 } else if (strcmp(descriptor, "[Ljava/lang/Object;") == 0) { 2577 new_class.Assign(GetClassRoot(kObjectArrayClass)); 2578 } else if (strcmp(descriptor, GetClassRootDescriptor(kJavaLangStringArrayClass)) == 0) { 2579 new_class.Assign(GetClassRoot(kJavaLangStringArrayClass)); 2580 } else if (strcmp(descriptor, 2581 GetClassRootDescriptor(kJavaLangReflectArtMethodArrayClass)) == 0) { 2582 new_class.Assign(GetClassRoot(kJavaLangReflectArtMethodArrayClass)); 2583 } else if (strcmp(descriptor, "[C") == 0) { 2584 new_class.Assign(GetClassRoot(kCharArrayClass)); 2585 } else if (strcmp(descriptor, "[I") == 0) { 2586 new_class.Assign(GetClassRoot(kIntArrayClass)); 2587 } else if (strcmp(descriptor, "[J") == 0) { 2588 new_class.Assign(GetClassRoot(kLongArrayClass)); 2589 } 2590 } 2591 if (new_class.Get() == nullptr) { 2592 new_class.Assign(AllocClass(self, mirror::Array::ClassSize())); 2593 if (new_class.Get() == nullptr) { 2594 return nullptr; 2595 } 2596 new_class->SetComponentType(component_type.Get()); 2597 } 2598 ObjectLock<mirror::Class> lock(self, new_class); // Must hold lock on object when initializing. 2599 DCHECK(new_class->GetComponentType() != nullptr); 2600 mirror::Class* java_lang_Object = GetClassRoot(kJavaLangObject); 2601 new_class->SetSuperClass(java_lang_Object); 2602 new_class->SetVTable(java_lang_Object->GetVTable()); 2603 new_class->SetPrimitiveType(Primitive::kPrimNot); 2604 new_class->SetClassLoader(component_type->GetClassLoader()); 2605 mirror::Class::SetStatus(new_class, mirror::Class::kStatusLoaded, self); 2606 { 2607 StackHandleScope<mirror::Class::kImtSize> hs2(self, 2608 Runtime::Current()->GetImtUnimplementedMethod()); 2609 new_class->PopulateEmbeddedImtAndVTable(&hs2); 2610 } 2611 mirror::Class::SetStatus(new_class, mirror::Class::kStatusInitialized, self); 2612 // don't need to set new_class->SetObjectSize(..) 2613 // because Object::SizeOf delegates to Array::SizeOf 2614 2615 2616 // All arrays have java/lang/Cloneable and java/io/Serializable as 2617 // interfaces. We need to set that up here, so that stuff like 2618 // "instanceof" works right. 2619 // 2620 // Note: The GC could run during the call to FindSystemClass, 2621 // so we need to make sure the class object is GC-valid while we're in 2622 // there. Do this by clearing the interface list so the GC will just 2623 // think that the entries are null. 2624 2625 2626 // Use the single, global copies of "interfaces" and "iftable" 2627 // (remember not to free them for arrays). 2628 { 2629 mirror::IfTable* array_iftable = array_iftable_.Read(); 2630 CHECK(array_iftable != nullptr); 2631 new_class->SetIfTable(array_iftable); 2632 } 2633 2634 // Inherit access flags from the component type. 2635 int access_flags = new_class->GetComponentType()->GetAccessFlags(); 2636 // Lose any implementation detail flags; in particular, arrays aren't finalizable. 2637 access_flags &= kAccJavaFlagsMask; 2638 // Arrays can't be used as a superclass or interface, so we want to add "abstract final" 2639 // and remove "interface". 2640 access_flags |= kAccAbstract | kAccFinal; 2641 access_flags &= ~kAccInterface; 2642 2643 new_class->SetAccessFlags(access_flags); 2644 2645 mirror::Class* existing = InsertClass(descriptor, new_class.Get(), hash); 2646 if (existing == nullptr) { 2647 return new_class.Get(); 2648 } 2649 // Another thread must have loaded the class after we 2650 // started but before we finished. Abandon what we've 2651 // done. 2652 // 2653 // (Yes, this happens.) 2654 2655 return existing; 2656} 2657 2658mirror::Class* ClassLinker::FindPrimitiveClass(char type) { 2659 switch (type) { 2660 case 'B': 2661 return GetClassRoot(kPrimitiveByte); 2662 case 'C': 2663 return GetClassRoot(kPrimitiveChar); 2664 case 'D': 2665 return GetClassRoot(kPrimitiveDouble); 2666 case 'F': 2667 return GetClassRoot(kPrimitiveFloat); 2668 case 'I': 2669 return GetClassRoot(kPrimitiveInt); 2670 case 'J': 2671 return GetClassRoot(kPrimitiveLong); 2672 case 'S': 2673 return GetClassRoot(kPrimitiveShort); 2674 case 'Z': 2675 return GetClassRoot(kPrimitiveBoolean); 2676 case 'V': 2677 return GetClassRoot(kPrimitiveVoid); 2678 default: 2679 break; 2680 } 2681 std::string printable_type(PrintableChar(type)); 2682 ThrowNoClassDefFoundError("Not a primitive type: %s", printable_type.c_str()); 2683 return nullptr; 2684} 2685 2686mirror::Class* ClassLinker::InsertClass(const char* descriptor, mirror::Class* klass, 2687 size_t hash) { 2688 if (VLOG_IS_ON(class_linker)) { 2689 mirror::DexCache* dex_cache = klass->GetDexCache(); 2690 std::string source; 2691 if (dex_cache != nullptr) { 2692 source += " from "; 2693 source += dex_cache->GetLocation()->ToModifiedUtf8(); 2694 } 2695 LOG(INFO) << "Loaded class " << descriptor << source; 2696 } 2697 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2698 mirror::Class* existing = LookupClassFromTableLocked(descriptor, klass->GetClassLoader(), hash); 2699 if (existing != nullptr) { 2700 return existing; 2701 } 2702 if (kIsDebugBuild && !klass->IsTemp() && klass->GetClassLoader() == nullptr && 2703 dex_cache_image_class_lookup_required_) { 2704 // Check a class loaded with the system class loader matches one in the image if the class 2705 // is in the image. 2706 existing = LookupClassFromImage(descriptor); 2707 if (existing != nullptr) { 2708 CHECK_EQ(klass, existing); 2709 } 2710 } 2711 VerifyObject(klass); 2712 class_table_.InsertWithHash(GcRoot<mirror::Class>(klass), hash); 2713 if (log_new_class_table_roots_) { 2714 new_class_roots_.push_back(GcRoot<mirror::Class>(klass)); 2715 } 2716 return nullptr; 2717} 2718 2719mirror::Class* ClassLinker::UpdateClass(const char* descriptor, mirror::Class* klass, 2720 size_t hash) { 2721 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2722 auto existing_it = class_table_.FindWithHash(std::make_pair(descriptor, klass->GetClassLoader()), 2723 hash); 2724 if (existing_it == class_table_.end()) { 2725 CHECK(klass->IsProxyClass()); 2726 return nullptr; 2727 } 2728 2729 mirror::Class* existing = existing_it->Read(); 2730 CHECK_NE(existing, klass) << descriptor; 2731 CHECK(!existing->IsResolved()) << descriptor; 2732 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusResolving) << descriptor; 2733 2734 CHECK(!klass->IsTemp()) << descriptor; 2735 if (kIsDebugBuild && klass->GetClassLoader() == nullptr && 2736 dex_cache_image_class_lookup_required_) { 2737 // Check a class loaded with the system class loader matches one in the image if the class 2738 // is in the image. 2739 existing = LookupClassFromImage(descriptor); 2740 if (existing != nullptr) { 2741 CHECK_EQ(klass, existing) << descriptor; 2742 } 2743 } 2744 VerifyObject(klass); 2745 2746 // Update the element in the hash set. 2747 *existing_it = GcRoot<mirror::Class>(klass); 2748 if (log_new_class_table_roots_) { 2749 new_class_roots_.push_back(GcRoot<mirror::Class>(klass)); 2750 } 2751 2752 return existing; 2753} 2754 2755bool ClassLinker::RemoveClass(const char* descriptor, mirror::ClassLoader* class_loader) { 2756 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2757 auto pair = std::make_pair(descriptor, class_loader); 2758 auto it = class_table_.Find(pair); 2759 if (it != class_table_.end()) { 2760 class_table_.Erase(it); 2761 return true; 2762 } 2763 it = pre_zygote_class_table_.Find(pair); 2764 if (it != pre_zygote_class_table_.end()) { 2765 pre_zygote_class_table_.Erase(it); 2766 return true; 2767 } 2768 return false; 2769} 2770 2771mirror::Class* ClassLinker::LookupClass(Thread* self, const char* descriptor, size_t hash, 2772 mirror::ClassLoader* class_loader) { 2773 { 2774 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 2775 mirror::Class* result = LookupClassFromTableLocked(descriptor, class_loader, hash); 2776 if (result != nullptr) { 2777 return result; 2778 } 2779 } 2780 if (class_loader != nullptr || !dex_cache_image_class_lookup_required_) { 2781 return nullptr; 2782 } else { 2783 // Lookup failed but need to search dex_caches_. 2784 mirror::Class* result = LookupClassFromImage(descriptor); 2785 if (result != nullptr) { 2786 InsertClass(descriptor, result, hash); 2787 } else { 2788 // Searching the image dex files/caches failed, we don't want to get into this situation 2789 // often as map searches are faster, so after kMaxFailedDexCacheLookups move all image 2790 // classes into the class table. 2791 constexpr uint32_t kMaxFailedDexCacheLookups = 1000; 2792 if (++failed_dex_cache_class_lookups_ > kMaxFailedDexCacheLookups) { 2793 MoveImageClassesToClassTable(); 2794 } 2795 } 2796 return result; 2797 } 2798} 2799 2800mirror::Class* ClassLinker::LookupClassFromTableLocked(const char* descriptor, 2801 mirror::ClassLoader* class_loader, 2802 size_t hash) { 2803 auto descriptor_pair = std::make_pair(descriptor, class_loader); 2804 auto it = pre_zygote_class_table_.FindWithHash(descriptor_pair, hash); 2805 if (it == pre_zygote_class_table_.end()) { 2806 it = class_table_.FindWithHash(descriptor_pair, hash); 2807 if (it == class_table_.end()) { 2808 return nullptr; 2809 } 2810 } 2811 return it->Read(); 2812} 2813 2814static mirror::ObjectArray<mirror::DexCache>* GetImageDexCaches() 2815 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 2816 gc::space::ImageSpace* image = Runtime::Current()->GetHeap()->GetImageSpace(); 2817 CHECK(image != nullptr); 2818 mirror::Object* root = image->GetImageHeader().GetImageRoot(ImageHeader::kDexCaches); 2819 return root->AsObjectArray<mirror::DexCache>(); 2820} 2821 2822void ClassLinker::MoveImageClassesToClassTable() { 2823 Thread* self = Thread::Current(); 2824 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_); 2825 if (!dex_cache_image_class_lookup_required_) { 2826 return; // All dex cache classes are already in the class table. 2827 } 2828 ScopedAssertNoThreadSuspension ants(self, "Moving image classes to class table"); 2829 mirror::ObjectArray<mirror::DexCache>* dex_caches = GetImageDexCaches(); 2830 std::string temp; 2831 for (int32_t i = 0; i < dex_caches->GetLength(); i++) { 2832 mirror::DexCache* dex_cache = dex_caches->Get(i); 2833 mirror::ObjectArray<mirror::Class>* types = dex_cache->GetResolvedTypes(); 2834 for (int32_t j = 0; j < types->GetLength(); j++) { 2835 mirror::Class* klass = types->Get(j); 2836 if (klass != nullptr) { 2837 DCHECK(klass->GetClassLoader() == nullptr); 2838 const char* descriptor = klass->GetDescriptor(&temp); 2839 size_t hash = ComputeModifiedUtf8Hash(descriptor); 2840 mirror::Class* existing = LookupClassFromTableLocked(descriptor, nullptr, hash); 2841 if (existing != nullptr) { 2842 CHECK_EQ(existing, klass) << PrettyClassAndClassLoader(existing) << " != " 2843 << PrettyClassAndClassLoader(klass); 2844 } else { 2845 class_table_.Insert(GcRoot<mirror::Class>(klass)); 2846 if (log_new_class_table_roots_) { 2847 new_class_roots_.push_back(GcRoot<mirror::Class>(klass)); 2848 } 2849 } 2850 } 2851 } 2852 } 2853 dex_cache_image_class_lookup_required_ = false; 2854} 2855 2856void ClassLinker::MoveClassTableToPreZygote() { 2857 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2858 DCHECK(pre_zygote_class_table_.Empty()); 2859 pre_zygote_class_table_ = std::move(class_table_); 2860 class_table_.Clear(); 2861} 2862 2863mirror::Class* ClassLinker::LookupClassFromImage(const char* descriptor) { 2864 ScopedAssertNoThreadSuspension ants(Thread::Current(), "Image class lookup"); 2865 mirror::ObjectArray<mirror::DexCache>* dex_caches = GetImageDexCaches(); 2866 for (int32_t i = 0; i < dex_caches->GetLength(); ++i) { 2867 mirror::DexCache* dex_cache = dex_caches->Get(i); 2868 const DexFile* dex_file = dex_cache->GetDexFile(); 2869 // Try binary searching the string/type index. 2870 const DexFile::StringId* string_id = dex_file->FindStringId(descriptor); 2871 if (string_id != nullptr) { 2872 const DexFile::TypeId* type_id = 2873 dex_file->FindTypeId(dex_file->GetIndexForStringId(*string_id)); 2874 if (type_id != nullptr) { 2875 uint16_t type_idx = dex_file->GetIndexForTypeId(*type_id); 2876 mirror::Class* klass = dex_cache->GetResolvedType(type_idx); 2877 if (klass != nullptr) { 2878 return klass; 2879 } 2880 } 2881 } 2882 } 2883 return nullptr; 2884} 2885 2886void ClassLinker::LookupClasses(const char* descriptor, std::vector<mirror::Class*>& result) { 2887 result.clear(); 2888 if (dex_cache_image_class_lookup_required_) { 2889 MoveImageClassesToClassTable(); 2890 } 2891 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 2892 while (true) { 2893 auto it = class_table_.Find(descriptor); 2894 if (it == class_table_.end()) { 2895 break; 2896 } 2897 result.push_back(it->Read()); 2898 class_table_.Erase(it); 2899 } 2900 for (mirror::Class* k : result) { 2901 class_table_.Insert(GcRoot<mirror::Class>(k)); 2902 } 2903 size_t pre_zygote_start = result.size(); 2904 // Now handle the pre zygote table. 2905 // Note: This dirties the pre-zygote table but shouldn't be an issue since LookupClasses is only 2906 // called from the debugger. 2907 while (true) { 2908 auto it = pre_zygote_class_table_.Find(descriptor); 2909 if (it == pre_zygote_class_table_.end()) { 2910 break; 2911 } 2912 result.push_back(it->Read()); 2913 pre_zygote_class_table_.Erase(it); 2914 } 2915 for (size_t i = pre_zygote_start; i < result.size(); ++i) { 2916 pre_zygote_class_table_.Insert(GcRoot<mirror::Class>(result[i])); 2917 } 2918} 2919 2920void ClassLinker::VerifyClass(Thread* self, Handle<mirror::Class> klass) { 2921 // TODO: assert that the monitor on the Class is held 2922 ObjectLock<mirror::Class> lock(self, klass); 2923 2924 // Don't attempt to re-verify if already sufficiently verified. 2925 if (klass->IsVerified()) { 2926 EnsurePreverifiedMethods(klass); 2927 return; 2928 } 2929 if (klass->IsCompileTimeVerified() && Runtime::Current()->IsAotCompiler()) { 2930 return; 2931 } 2932 2933 // The class might already be erroneous, for example at compile time if we attempted to verify 2934 // this class as a parent to another. 2935 if (klass->IsErroneous()) { 2936 ThrowEarlierClassFailure(klass.Get()); 2937 return; 2938 } 2939 2940 if (klass->GetStatus() == mirror::Class::kStatusResolved) { 2941 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerifying, self); 2942 } else { 2943 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime) 2944 << PrettyClass(klass.Get()); 2945 CHECK(!Runtime::Current()->IsAotCompiler()); 2946 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerifyingAtRuntime, self); 2947 } 2948 2949 // Skip verification if disabled. 2950 if (!Runtime::Current()->IsVerificationEnabled()) { 2951 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self); 2952 EnsurePreverifiedMethods(klass); 2953 return; 2954 } 2955 2956 // Verify super class. 2957 StackHandleScope<2> hs(self); 2958 Handle<mirror::Class> super(hs.NewHandle(klass->GetSuperClass())); 2959 if (super.Get() != nullptr) { 2960 // Acquire lock to prevent races on verifying the super class. 2961 ObjectLock<mirror::Class> super_lock(self, super); 2962 2963 if (!super->IsVerified() && !super->IsErroneous()) { 2964 VerifyClass(self, super); 2965 } 2966 if (!super->IsCompileTimeVerified()) { 2967 std::string error_msg( 2968 StringPrintf("Rejecting class %s that attempts to sub-class erroneous class %s", 2969 PrettyDescriptor(klass.Get()).c_str(), 2970 PrettyDescriptor(super.Get()).c_str())); 2971 LOG(WARNING) << error_msg << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8(); 2972 Handle<mirror::Throwable> cause(hs.NewHandle(self->GetException())); 2973 if (cause.Get() != nullptr) { 2974 self->ClearException(); 2975 } 2976 ThrowVerifyError(klass.Get(), "%s", error_msg.c_str()); 2977 if (cause.Get() != nullptr) { 2978 self->GetException()->SetCause(cause.Get()); 2979 } 2980 ClassReference ref(klass->GetDexCache()->GetDexFile(), klass->GetDexClassDefIndex()); 2981 if (Runtime::Current()->IsAotCompiler()) { 2982 Runtime::Current()->GetCompilerCallbacks()->ClassRejected(ref); 2983 } 2984 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 2985 return; 2986 } 2987 } 2988 2989 // Try to use verification information from the oat file, otherwise do runtime verification. 2990 const DexFile& dex_file = *klass->GetDexCache()->GetDexFile(); 2991 mirror::Class::Status oat_file_class_status(mirror::Class::kStatusNotReady); 2992 bool preverified = VerifyClassUsingOatFile(dex_file, klass.Get(), oat_file_class_status); 2993 if (oat_file_class_status == mirror::Class::kStatusError) { 2994 VLOG(class_linker) << "Skipping runtime verification of erroneous class " 2995 << PrettyDescriptor(klass.Get()) << " in " 2996 << klass->GetDexCache()->GetLocation()->ToModifiedUtf8(); 2997 ThrowVerifyError(klass.Get(), "Rejecting class %s because it failed compile-time verification", 2998 PrettyDescriptor(klass.Get()).c_str()); 2999 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3000 return; 3001 } 3002 verifier::MethodVerifier::FailureKind verifier_failure = verifier::MethodVerifier::kNoFailure; 3003 std::string error_msg; 3004 if (!preverified) { 3005 verifier_failure = verifier::MethodVerifier::VerifyClass(self, klass.Get(), 3006 Runtime::Current()->IsAotCompiler(), 3007 &error_msg); 3008 } 3009 if (preverified || verifier_failure != verifier::MethodVerifier::kHardFailure) { 3010 if (!preverified && verifier_failure != verifier::MethodVerifier::kNoFailure) { 3011 VLOG(class_linker) << "Soft verification failure in class " << PrettyDescriptor(klass.Get()) 3012 << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8() 3013 << " because: " << error_msg; 3014 } 3015 self->AssertNoPendingException(); 3016 // Make sure all classes referenced by catch blocks are resolved. 3017 ResolveClassExceptionHandlerTypes(dex_file, klass); 3018 if (verifier_failure == verifier::MethodVerifier::kNoFailure) { 3019 // Even though there were no verifier failures we need to respect whether the super-class 3020 // was verified or requiring runtime reverification. 3021 if (super.Get() == nullptr || super->IsVerified()) { 3022 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self); 3023 } else { 3024 CHECK_EQ(super->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime); 3025 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetryVerificationAtRuntime, self); 3026 // Pretend a soft failure occured so that we don't consider the class verified below. 3027 verifier_failure = verifier::MethodVerifier::kSoftFailure; 3028 } 3029 } else { 3030 CHECK_EQ(verifier_failure, verifier::MethodVerifier::kSoftFailure); 3031 // Soft failures at compile time should be retried at runtime. Soft 3032 // failures at runtime will be handled by slow paths in the generated 3033 // code. Set status accordingly. 3034 if (Runtime::Current()->IsAotCompiler()) { 3035 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetryVerificationAtRuntime, self); 3036 } else { 3037 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self); 3038 // As this is a fake verified status, make sure the methods are _not_ marked preverified 3039 // later. 3040 klass->SetPreverified(); 3041 } 3042 } 3043 } else { 3044 LOG(WARNING) << "Verification failed on class " << PrettyDescriptor(klass.Get()) 3045 << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8() 3046 << " because: " << error_msg; 3047 self->AssertNoPendingException(); 3048 ThrowVerifyError(klass.Get(), "%s", error_msg.c_str()); 3049 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3050 } 3051 if (preverified || verifier_failure == verifier::MethodVerifier::kNoFailure) { 3052 // Class is verified so we don't need to do any access check on its methods. 3053 // Let the interpreter know it by setting the kAccPreverified flag onto each 3054 // method. 3055 // Note: we're going here during compilation and at runtime. When we set the 3056 // kAccPreverified flag when compiling image classes, the flag is recorded 3057 // in the image and is set when loading the image. 3058 EnsurePreverifiedMethods(klass); 3059 } 3060} 3061 3062void ClassLinker::EnsurePreverifiedMethods(Handle<mirror::Class> klass) { 3063 if (!klass->IsPreverified()) { 3064 klass->SetPreverifiedFlagOnAllMethods(); 3065 klass->SetPreverified(); 3066 } 3067} 3068 3069bool ClassLinker::VerifyClassUsingOatFile(const DexFile& dex_file, mirror::Class* klass, 3070 mirror::Class::Status& oat_file_class_status) { 3071 // If we're compiling, we can only verify the class using the oat file if 3072 // we are not compiling the image or if the class we're verifying is not part of 3073 // the app. In other words, we will only check for preverification of bootclasspath 3074 // classes. 3075 if (Runtime::Current()->IsAotCompiler()) { 3076 // Are we compiling the bootclasspath? 3077 if (Runtime::Current()->GetCompilerCallbacks()->IsBootImage()) { 3078 return false; 3079 } 3080 // We are compiling an app (not the image). 3081 3082 // Is this an app class? (I.e. not a bootclasspath class) 3083 if (klass->GetClassLoader() != nullptr) { 3084 return false; 3085 } 3086 } 3087 3088 const OatFile::OatDexFile* oat_dex_file = dex_file.GetOatDexFile(); 3089 // In case we run without an image there won't be a backing oat file. 3090 if (oat_dex_file == nullptr) { 3091 return false; 3092 } 3093 3094 // We may be running with a preopted oat file but without image. In this case, 3095 // we don't skip verification of preverified classes to ensure we initialize 3096 // dex caches with all types resolved during verification. 3097 // We need to trust image classes, as these might be coming out of a pre-opted, quickened boot 3098 // image (that we just failed loading), and the verifier can't be run on quickened opcodes when 3099 // the runtime isn't started. On the other hand, app classes can be re-verified even if they are 3100 // already pre-opted, as then the runtime is started. 3101 if (!Runtime::Current()->IsAotCompiler() && 3102 !Runtime::Current()->GetHeap()->HasImageSpace() && 3103 klass->GetClassLoader() != nullptr) { 3104 return false; 3105 } 3106 3107 uint16_t class_def_index = klass->GetDexClassDefIndex(); 3108 oat_file_class_status = oat_dex_file->GetOatClass(class_def_index).GetStatus(); 3109 if (oat_file_class_status == mirror::Class::kStatusVerified || 3110 oat_file_class_status == mirror::Class::kStatusInitialized) { 3111 return true; 3112 } 3113 if (oat_file_class_status == mirror::Class::kStatusRetryVerificationAtRuntime) { 3114 // Compile time verification failed with a soft error. Compile time verification can fail 3115 // because we have incomplete type information. Consider the following: 3116 // class ... { 3117 // Foo x; 3118 // .... () { 3119 // if (...) { 3120 // v1 gets assigned a type of resolved class Foo 3121 // } else { 3122 // v1 gets assigned a type of unresolved class Bar 3123 // } 3124 // iput x = v1 3125 // } } 3126 // when we merge v1 following the if-the-else it results in Conflict 3127 // (see verifier::RegType::Merge) as we can't know the type of Bar and we could possibly be 3128 // allowing an unsafe assignment to the field x in the iput (javac may have compiled this as 3129 // it knew Bar was a sub-class of Foo, but for us this may have been moved into a separate apk 3130 // at compile time). 3131 return false; 3132 } 3133 if (oat_file_class_status == mirror::Class::kStatusError) { 3134 // Compile time verification failed with a hard error. This is caused by invalid instructions 3135 // in the class. These errors are unrecoverable. 3136 return false; 3137 } 3138 if (oat_file_class_status == mirror::Class::kStatusNotReady) { 3139 // Status is uninitialized if we couldn't determine the status at compile time, for example, 3140 // not loading the class. 3141 // TODO: when the verifier doesn't rely on Class-es failing to resolve/load the type hierarchy 3142 // isn't a problem and this case shouldn't occur 3143 return false; 3144 } 3145 std::string temp; 3146 LOG(FATAL) << "Unexpected class status: " << oat_file_class_status 3147 << " " << dex_file.GetLocation() << " " << PrettyClass(klass) << " " 3148 << klass->GetDescriptor(&temp); 3149 UNREACHABLE(); 3150} 3151 3152void ClassLinker::ResolveClassExceptionHandlerTypes(const DexFile& dex_file, 3153 Handle<mirror::Class> klass) { 3154 for (size_t i = 0; i < klass->NumDirectMethods(); i++) { 3155 ResolveMethodExceptionHandlerTypes(dex_file, klass->GetDirectMethod(i)); 3156 } 3157 for (size_t i = 0; i < klass->NumVirtualMethods(); i++) { 3158 ResolveMethodExceptionHandlerTypes(dex_file, klass->GetVirtualMethod(i)); 3159 } 3160} 3161 3162void ClassLinker::ResolveMethodExceptionHandlerTypes(const DexFile& dex_file, 3163 mirror::ArtMethod* method) { 3164 // similar to DexVerifier::ScanTryCatchBlocks and dex2oat's ResolveExceptionsForMethod. 3165 const DexFile::CodeItem* code_item = dex_file.GetCodeItem(method->GetCodeItemOffset()); 3166 if (code_item == nullptr) { 3167 return; // native or abstract method 3168 } 3169 if (code_item->tries_size_ == 0) { 3170 return; // nothing to process 3171 } 3172 const uint8_t* handlers_ptr = DexFile::GetCatchHandlerData(*code_item, 0); 3173 uint32_t handlers_size = DecodeUnsignedLeb128(&handlers_ptr); 3174 ClassLinker* linker = Runtime::Current()->GetClassLinker(); 3175 for (uint32_t idx = 0; idx < handlers_size; idx++) { 3176 CatchHandlerIterator iterator(handlers_ptr); 3177 for (; iterator.HasNext(); iterator.Next()) { 3178 // Ensure exception types are resolved so that they don't need resolution to be delivered, 3179 // unresolved exception types will be ignored by exception delivery 3180 if (iterator.GetHandlerTypeIndex() != DexFile::kDexNoIndex16) { 3181 mirror::Class* exception_type = linker->ResolveType(iterator.GetHandlerTypeIndex(), method); 3182 if (exception_type == nullptr) { 3183 DCHECK(Thread::Current()->IsExceptionPending()); 3184 Thread::Current()->ClearException(); 3185 } 3186 } 3187 } 3188 handlers_ptr = iterator.EndDataPointer(); 3189 } 3190} 3191 3192static void CheckProxyConstructor(mirror::ArtMethod* constructor); 3193static void CheckProxyMethod(Handle<mirror::ArtMethod> method, 3194 Handle<mirror::ArtMethod> prototype); 3195 3196mirror::Class* ClassLinker::CreateProxyClass(ScopedObjectAccessAlreadyRunnable& soa, jstring name, 3197 jobjectArray interfaces, jobject loader, 3198 jobjectArray methods, jobjectArray throws) { 3199 Thread* self = soa.Self(); 3200 StackHandleScope<9> hs(self); 3201 MutableHandle<mirror::Class> klass(hs.NewHandle( 3202 AllocClass(self, GetClassRoot(kJavaLangClass), sizeof(mirror::Class)))); 3203 if (klass.Get() == nullptr) { 3204 CHECK(self->IsExceptionPending()); // OOME. 3205 return nullptr; 3206 } 3207 DCHECK(klass->GetClass() != nullptr); 3208 klass->SetObjectSize(sizeof(mirror::Proxy)); 3209 // Set the class access flags incl. preverified, so we do not try to set the flag on the methods. 3210 klass->SetAccessFlags(kAccClassIsProxy | kAccPublic | kAccFinal | kAccPreverified); 3211 klass->SetClassLoader(soa.Decode<mirror::ClassLoader*>(loader)); 3212 DCHECK_EQ(klass->GetPrimitiveType(), Primitive::kPrimNot); 3213 klass->SetName(soa.Decode<mirror::String*>(name)); 3214 mirror::Class* proxy_class = GetClassRoot(kJavaLangReflectProxy); 3215 klass->SetDexCache(proxy_class->GetDexCache()); 3216 mirror::Class::SetStatus(klass, mirror::Class::kStatusIdx, self); 3217 3218 // Instance fields are inherited, but we add a couple of static fields... 3219 const size_t num_fields = 2; 3220 ArtField* sfields = AllocArtFieldArray(self, num_fields); 3221 klass->SetSFields(sfields); 3222 klass->SetNumStaticFields(num_fields); 3223 3224 // 1. Create a static field 'interfaces' that holds the _declared_ interfaces implemented by 3225 // our proxy, so Class.getInterfaces doesn't return the flattened set. 3226 ArtField* interfaces_sfield = &sfields[0]; 3227 interfaces_sfield->SetDexFieldIndex(0); 3228 interfaces_sfield->SetDeclaringClass(klass.Get()); 3229 interfaces_sfield->SetAccessFlags(kAccStatic | kAccPublic | kAccFinal); 3230 3231 // 2. Create a static field 'throws' that holds exceptions thrown by our methods. 3232 ArtField* throws_sfield = &sfields[1]; 3233 throws_sfield->SetDexFieldIndex(1); 3234 throws_sfield->SetDeclaringClass(klass.Get()); 3235 throws_sfield->SetAccessFlags(kAccStatic | kAccPublic | kAccFinal); 3236 3237 // Proxies have 1 direct method, the constructor 3238 { 3239 mirror::ObjectArray<mirror::ArtMethod>* directs = AllocArtMethodArray(self, 1); 3240 if (UNLIKELY(directs == nullptr)) { 3241 CHECK(self->IsExceptionPending()); // OOME. 3242 return nullptr; 3243 } 3244 klass->SetDirectMethods(directs); 3245 mirror::ArtMethod* constructor = CreateProxyConstructor(self, klass, proxy_class); 3246 if (UNLIKELY(constructor == nullptr)) { 3247 CHECK(self->IsExceptionPending()); // OOME. 3248 return nullptr; 3249 } 3250 klass->SetDirectMethod(0, constructor); 3251 } 3252 3253 // Create virtual method using specified prototypes. 3254 auto h_methods = hs.NewHandle(soa.Decode<mirror::ObjectArray<mirror::Method>*>(methods)); 3255 DCHECK_EQ(h_methods->GetClass(), mirror::Method::ArrayClass()) 3256 << PrettyClass(h_methods->GetClass()); 3257 const size_t num_virtual_methods = h_methods->GetLength(); 3258 { 3259 mirror::ObjectArray<mirror::ArtMethod>* virtuals = AllocArtMethodArray(self, 3260 num_virtual_methods); 3261 if (UNLIKELY(virtuals == nullptr)) { 3262 CHECK(self->IsExceptionPending()); // OOME. 3263 return nullptr; 3264 } 3265 klass->SetVirtualMethods(virtuals); 3266 } 3267 for (size_t i = 0; i < num_virtual_methods; ++i) { 3268 StackHandleScope<1> hs2(self); 3269 Handle<mirror::ArtMethod> prototype(hs2.NewHandle(h_methods->Get(i)->GetArtMethod())); 3270 mirror::ArtMethod* clone = CreateProxyMethod(self, klass, prototype); 3271 if (UNLIKELY(clone == nullptr)) { 3272 CHECK(self->IsExceptionPending()); // OOME. 3273 return nullptr; 3274 } 3275 klass->SetVirtualMethod(i, clone); 3276 } 3277 3278 klass->SetSuperClass(proxy_class); // The super class is java.lang.reflect.Proxy 3279 mirror::Class::SetStatus(klass, mirror::Class::kStatusLoaded, self); // Now effectively in the loaded state. 3280 self->AssertNoPendingException(); 3281 3282 std::string descriptor(GetDescriptorForProxy(klass.Get())); 3283 mirror::Class* new_class = nullptr; 3284 { 3285 // Must hold lock on object when resolved. 3286 ObjectLock<mirror::Class> resolution_lock(self, klass); 3287 // Link the fields and virtual methods, creating vtable and iftables 3288 Handle<mirror::ObjectArray<mirror::Class> > h_interfaces( 3289 hs.NewHandle(soa.Decode<mirror::ObjectArray<mirror::Class>*>(interfaces))); 3290 if (!LinkClass(self, descriptor.c_str(), klass, h_interfaces, &new_class)) { 3291 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3292 return nullptr; 3293 } 3294 } 3295 3296 CHECK(klass->IsRetired()); 3297 CHECK_NE(klass.Get(), new_class); 3298 klass.Assign(new_class); 3299 3300 CHECK_EQ(interfaces_sfield->GetDeclaringClass(), new_class); 3301 interfaces_sfield->SetObject<false>(klass.Get(), 3302 soa.Decode<mirror::ObjectArray<mirror::Class>*>(interfaces)); 3303 CHECK_EQ(throws_sfield->GetDeclaringClass(), new_class); 3304 throws_sfield->SetObject<false>(klass.Get(), 3305 soa.Decode<mirror::ObjectArray<mirror::ObjectArray<mirror::Class> >*>(throws)); 3306 3307 { 3308 // Lock on klass is released. Lock new class object. 3309 ObjectLock<mirror::Class> initialization_lock(self, klass); 3310 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitialized, self); 3311 } 3312 3313 // sanity checks 3314 if (kIsDebugBuild) { 3315 CHECK(klass->GetIFields() == nullptr); 3316 CheckProxyConstructor(klass->GetDirectMethod(0)); 3317 for (size_t i = 0; i < num_virtual_methods; ++i) { 3318 StackHandleScope<2> hs2(self); 3319 Handle<mirror::ArtMethod> prototype(hs2.NewHandle(h_methods->Get(i)->GetArtMethod())); 3320 Handle<mirror::ArtMethod> virtual_method(hs2.NewHandle(klass->GetVirtualMethod(i))); 3321 CheckProxyMethod(virtual_method, prototype); 3322 } 3323 3324 mirror::String* decoded_name = soa.Decode<mirror::String*>(name); 3325 std::string interfaces_field_name(StringPrintf("java.lang.Class[] %s.interfaces", 3326 decoded_name->ToModifiedUtf8().c_str())); 3327 CHECK_EQ(PrettyField(klass->GetStaticField(0)), interfaces_field_name); 3328 3329 std::string throws_field_name(StringPrintf("java.lang.Class[][] %s.throws", 3330 decoded_name->ToModifiedUtf8().c_str())); 3331 CHECK_EQ(PrettyField(klass->GetStaticField(1)), throws_field_name); 3332 3333 CHECK_EQ(klass.Get()->GetInterfaces(), 3334 soa.Decode<mirror::ObjectArray<mirror::Class>*>(interfaces)); 3335 CHECK_EQ(klass.Get()->GetThrows(), 3336 soa.Decode<mirror::ObjectArray<mirror::ObjectArray<mirror::Class>>*>(throws)); 3337 } 3338 mirror::Class* existing = InsertClass(descriptor.c_str(), klass.Get(), 3339 ComputeModifiedUtf8Hash(descriptor.c_str())); 3340 CHECK(existing == nullptr); 3341 return klass.Get(); 3342} 3343 3344std::string ClassLinker::GetDescriptorForProxy(mirror::Class* proxy_class) { 3345 DCHECK(proxy_class->IsProxyClass()); 3346 mirror::String* name = proxy_class->GetName(); 3347 DCHECK(name != nullptr); 3348 return DotToDescriptor(name->ToModifiedUtf8().c_str()); 3349} 3350 3351mirror::ArtMethod* ClassLinker::FindMethodForProxy(mirror::Class* proxy_class, 3352 mirror::ArtMethod* proxy_method) { 3353 DCHECK(proxy_class->IsProxyClass()); 3354 DCHECK(proxy_method->IsProxyMethod()); 3355 { 3356 ReaderMutexLock mu(Thread::Current(), dex_lock_); 3357 // Locate the dex cache of the original interface/Object 3358 for (const GcRoot<mirror::DexCache>& root : dex_caches_) { 3359 auto* dex_cache = root.Read(); 3360 if (proxy_method->HasSameDexCacheResolvedTypes(dex_cache->GetResolvedTypes())) { 3361 mirror::ArtMethod* resolved_method = dex_cache->GetResolvedMethod( 3362 proxy_method->GetDexMethodIndex()); 3363 CHECK(resolved_method != nullptr); 3364 return resolved_method; 3365 } 3366 } 3367 } 3368 LOG(FATAL) << "Didn't find dex cache for " << PrettyClass(proxy_class) << " " 3369 << PrettyMethod(proxy_method); 3370 UNREACHABLE(); 3371} 3372 3373 3374mirror::ArtMethod* ClassLinker::CreateProxyConstructor(Thread* self, 3375 Handle<mirror::Class> klass, 3376 mirror::Class* proxy_class) { 3377 // Create constructor for Proxy that must initialize h 3378 mirror::ObjectArray<mirror::ArtMethod>* proxy_direct_methods = 3379 proxy_class->GetDirectMethods(); 3380 CHECK_EQ(proxy_direct_methods->GetLength(), 16); 3381 mirror::ArtMethod* proxy_constructor = proxy_direct_methods->Get(2); 3382 // Ensure constructor is in dex cache so that we can use the dex cache to look up the overridden 3383 // constructor method. 3384 proxy_class->GetDexCache()->SetResolvedMethod(proxy_constructor->GetDexMethodIndex(), 3385 proxy_constructor); 3386 // Clone the existing constructor of Proxy (our constructor would just invoke it so steal its 3387 // code_ too) 3388 mirror::ArtMethod* constructor = down_cast<mirror::ArtMethod*>(proxy_constructor->Clone(self)); 3389 if (constructor == nullptr) { 3390 CHECK(self->IsExceptionPending()); // OOME. 3391 return nullptr; 3392 } 3393 // Make this constructor public and fix the class to be our Proxy version 3394 constructor->SetAccessFlags((constructor->GetAccessFlags() & ~kAccProtected) | kAccPublic); 3395 constructor->SetDeclaringClass(klass.Get()); 3396 return constructor; 3397} 3398 3399static void CheckProxyConstructor(mirror::ArtMethod* constructor) 3400 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3401 CHECK(constructor->IsConstructor()); 3402 CHECK_STREQ(constructor->GetName(), "<init>"); 3403 CHECK_STREQ(constructor->GetSignature().ToString().c_str(), 3404 "(Ljava/lang/reflect/InvocationHandler;)V"); 3405 DCHECK(constructor->IsPublic()); 3406} 3407 3408mirror::ArtMethod* ClassLinker::CreateProxyMethod(Thread* self, 3409 Handle<mirror::Class> klass, 3410 Handle<mirror::ArtMethod> prototype) { 3411 // Ensure prototype is in dex cache so that we can use the dex cache to look up the overridden 3412 // prototype method 3413 auto* dex_cache = prototype->GetDeclaringClass()->GetDexCache(); 3414 // Avoid dirtying the dex cache unless we need to. 3415 if (dex_cache->GetResolvedMethod(prototype->GetDexMethodIndex()) != prototype.Get()) { 3416 dex_cache->SetResolvedMethod(prototype->GetDexMethodIndex(), prototype.Get()); 3417 } 3418 // We steal everything from the prototype (such as DexCache, invoke stub, etc.) then specialize 3419 // as necessary 3420 mirror::ArtMethod* method = down_cast<mirror::ArtMethod*>(prototype->Clone(self)); 3421 if (UNLIKELY(method == nullptr)) { 3422 CHECK(self->IsExceptionPending()); // OOME. 3423 return nullptr; 3424 } 3425 3426 // Set class to be the concrete proxy class and clear the abstract flag, modify exceptions to 3427 // the intersection of throw exceptions as defined in Proxy 3428 method->SetDeclaringClass(klass.Get()); 3429 method->SetAccessFlags((method->GetAccessFlags() & ~kAccAbstract) | kAccFinal); 3430 3431 // At runtime the method looks like a reference and argument saving method, clone the code 3432 // related parameters from this method. 3433 method->SetEntryPointFromQuickCompiledCode(GetQuickProxyInvokeHandler()); 3434 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 3435 3436 return method; 3437} 3438 3439static void CheckProxyMethod(Handle<mirror::ArtMethod> method, 3440 Handle<mirror::ArtMethod> prototype) 3441 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3442 // Basic sanity 3443 CHECK(!prototype->IsFinal()); 3444 CHECK(method->IsFinal()); 3445 CHECK(!method->IsAbstract()); 3446 3447 // The proxy method doesn't have its own dex cache or dex file and so it steals those of its 3448 // interface prototype. The exception to this are Constructors and the Class of the Proxy itself. 3449 CHECK(prototype->HasSameDexCacheResolvedMethods(method.Get())); 3450 CHECK(prototype->HasSameDexCacheResolvedTypes(method.Get())); 3451 CHECK_EQ(prototype->GetDeclaringClass()->GetDexCache(), method->GetDexCache()); 3452 CHECK_EQ(prototype->GetDexMethodIndex(), method->GetDexMethodIndex()); 3453 3454 CHECK_STREQ(method->GetName(), prototype->GetName()); 3455 CHECK_STREQ(method->GetShorty(), prototype->GetShorty()); 3456 // More complex sanity - via dex cache 3457 CHECK_EQ(method->GetInterfaceMethodIfProxy()->GetReturnType(), prototype->GetReturnType()); 3458} 3459 3460static bool CanWeInitializeClass(mirror::Class* klass, bool can_init_statics, 3461 bool can_init_parents) 3462 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3463 if (can_init_statics && can_init_parents) { 3464 return true; 3465 } 3466 if (!can_init_statics) { 3467 // Check if there's a class initializer. 3468 mirror::ArtMethod* clinit = klass->FindClassInitializer(); 3469 if (clinit != nullptr) { 3470 return false; 3471 } 3472 // Check if there are encoded static values needing initialization. 3473 if (klass->NumStaticFields() != 0) { 3474 const DexFile::ClassDef* dex_class_def = klass->GetClassDef(); 3475 DCHECK(dex_class_def != nullptr); 3476 if (dex_class_def->static_values_off_ != 0) { 3477 return false; 3478 } 3479 } 3480 } 3481 if (!klass->IsInterface() && klass->HasSuperClass()) { 3482 mirror::Class* super_class = klass->GetSuperClass(); 3483 if (!can_init_parents && !super_class->IsInitialized()) { 3484 return false; 3485 } else { 3486 if (!CanWeInitializeClass(super_class, can_init_statics, can_init_parents)) { 3487 return false; 3488 } 3489 } 3490 } 3491 return true; 3492} 3493 3494bool ClassLinker::InitializeClass(Thread* self, Handle<mirror::Class> klass, 3495 bool can_init_statics, bool can_init_parents) { 3496 // see JLS 3rd edition, 12.4.2 "Detailed Initialization Procedure" for the locking protocol 3497 3498 // Are we already initialized and therefore done? 3499 // Note: we differ from the JLS here as we don't do this under the lock, this is benign as 3500 // an initialized class will never change its state. 3501 if (klass->IsInitialized()) { 3502 return true; 3503 } 3504 3505 // Fast fail if initialization requires a full runtime. Not part of the JLS. 3506 if (!CanWeInitializeClass(klass.Get(), can_init_statics, can_init_parents)) { 3507 return false; 3508 } 3509 3510 self->AllowThreadSuspension(); 3511 uint64_t t0; 3512 { 3513 ObjectLock<mirror::Class> lock(self, klass); 3514 3515 // Re-check under the lock in case another thread initialized ahead of us. 3516 if (klass->IsInitialized()) { 3517 return true; 3518 } 3519 3520 // Was the class already found to be erroneous? Done under the lock to match the JLS. 3521 if (klass->IsErroneous()) { 3522 ThrowEarlierClassFailure(klass.Get()); 3523 VlogClassInitializationFailure(klass); 3524 return false; 3525 } 3526 3527 CHECK(klass->IsResolved()) << PrettyClass(klass.Get()) << ": state=" << klass->GetStatus(); 3528 3529 if (!klass->IsVerified()) { 3530 VerifyClass(self, klass); 3531 if (!klass->IsVerified()) { 3532 // We failed to verify, expect either the klass to be erroneous or verification failed at 3533 // compile time. 3534 if (klass->IsErroneous()) { 3535 CHECK(self->IsExceptionPending()); 3536 VlogClassInitializationFailure(klass); 3537 } else { 3538 CHECK(Runtime::Current()->IsAotCompiler()); 3539 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime); 3540 } 3541 return false; 3542 } else { 3543 self->AssertNoPendingException(); 3544 } 3545 } 3546 3547 // If the class is kStatusInitializing, either this thread is 3548 // initializing higher up the stack or another thread has beat us 3549 // to initializing and we need to wait. Either way, this 3550 // invocation of InitializeClass will not be responsible for 3551 // running <clinit> and will return. 3552 if (klass->GetStatus() == mirror::Class::kStatusInitializing) { 3553 // Could have got an exception during verification. 3554 if (self->IsExceptionPending()) { 3555 VlogClassInitializationFailure(klass); 3556 return false; 3557 } 3558 // We caught somebody else in the act; was it us? 3559 if (klass->GetClinitThreadId() == self->GetTid()) { 3560 // Yes. That's fine. Return so we can continue initializing. 3561 return true; 3562 } 3563 // No. That's fine. Wait for another thread to finish initializing. 3564 return WaitForInitializeClass(klass, self, lock); 3565 } 3566 3567 if (!ValidateSuperClassDescriptors(klass)) { 3568 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3569 return false; 3570 } 3571 self->AllowThreadSuspension(); 3572 3573 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusVerified) << PrettyClass(klass.Get()); 3574 3575 // From here out other threads may observe that we're initializing and so changes of state 3576 // require the a notification. 3577 klass->SetClinitThreadId(self->GetTid()); 3578 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitializing, self); 3579 3580 t0 = NanoTime(); 3581 } 3582 3583 // Initialize super classes, must be done while initializing for the JLS. 3584 if (!klass->IsInterface() && klass->HasSuperClass()) { 3585 mirror::Class* super_class = klass->GetSuperClass(); 3586 if (!super_class->IsInitialized()) { 3587 CHECK(!super_class->IsInterface()); 3588 CHECK(can_init_parents); 3589 StackHandleScope<1> hs(self); 3590 Handle<mirror::Class> handle_scope_super(hs.NewHandle(super_class)); 3591 bool super_initialized = InitializeClass(self, handle_scope_super, can_init_statics, true); 3592 if (!super_initialized) { 3593 // The super class was verified ahead of entering initializing, we should only be here if 3594 // the super class became erroneous due to initialization. 3595 CHECK(handle_scope_super->IsErroneous() && self->IsExceptionPending()) 3596 << "Super class initialization failed for " 3597 << PrettyDescriptor(handle_scope_super.Get()) 3598 << " that has unexpected status " << handle_scope_super->GetStatus() 3599 << "\nPending exception:\n" 3600 << (self->GetException() != nullptr ? self->GetException()->Dump() : ""); 3601 ObjectLock<mirror::Class> lock(self, klass); 3602 // Initialization failed because the super-class is erroneous. 3603 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3604 return false; 3605 } 3606 } 3607 } 3608 3609 const size_t num_static_fields = klass->NumStaticFields(); 3610 if (num_static_fields > 0) { 3611 const DexFile::ClassDef* dex_class_def = klass->GetClassDef(); 3612 CHECK(dex_class_def != nullptr); 3613 const DexFile& dex_file = klass->GetDexFile(); 3614 StackHandleScope<3> hs(self); 3615 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(klass->GetClassLoader())); 3616 Handle<mirror::DexCache> dex_cache(hs.NewHandle(klass->GetDexCache())); 3617 3618 // Eagerly fill in static fields so that the we don't have to do as many expensive 3619 // Class::FindStaticField in ResolveField. 3620 for (size_t i = 0; i < num_static_fields; ++i) { 3621 ArtField* field = klass->GetStaticField(i); 3622 const uint32_t field_idx = field->GetDexFieldIndex(); 3623 ArtField* resolved_field = dex_cache->GetResolvedField(field_idx, image_pointer_size_); 3624 if (resolved_field == nullptr) { 3625 dex_cache->SetResolvedField(field_idx, field, image_pointer_size_); 3626 } else { 3627 DCHECK_EQ(field, resolved_field); 3628 } 3629 } 3630 3631 EncodedStaticFieldValueIterator value_it(dex_file, &dex_cache, &class_loader, 3632 this, *dex_class_def); 3633 const uint8_t* class_data = dex_file.GetClassData(*dex_class_def); 3634 ClassDataItemIterator field_it(dex_file, class_data); 3635 if (value_it.HasNext()) { 3636 DCHECK(field_it.HasNextStaticField()); 3637 CHECK(can_init_statics); 3638 for ( ; value_it.HasNext(); value_it.Next(), field_it.Next()) { 3639 ArtField* field = ResolveField( 3640 dex_file, field_it.GetMemberIndex(), dex_cache, class_loader, true); 3641 if (Runtime::Current()->IsActiveTransaction()) { 3642 value_it.ReadValueToField<true>(field); 3643 } else { 3644 value_it.ReadValueToField<false>(field); 3645 } 3646 DCHECK(!value_it.HasNext() || field_it.HasNextStaticField()); 3647 } 3648 } 3649 } 3650 3651 mirror::ArtMethod* clinit = klass->FindClassInitializer(); 3652 if (clinit != nullptr) { 3653 CHECK(can_init_statics); 3654 JValue result; 3655 clinit->Invoke(self, nullptr, 0, &result, "V"); 3656 } 3657 3658 self->AllowThreadSuspension(); 3659 uint64_t t1 = NanoTime(); 3660 3661 bool success = true; 3662 { 3663 ObjectLock<mirror::Class> lock(self, klass); 3664 3665 if (self->IsExceptionPending()) { 3666 WrapExceptionInInitializer(klass); 3667 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3668 success = false; 3669 } else if (Runtime::Current()->IsTransactionAborted()) { 3670 // The exception thrown when the transaction aborted has been caught and cleared 3671 // so we need to throw it again now. 3672 VLOG(compiler) << "Return from class initializer of " << PrettyDescriptor(klass.Get()) 3673 << " without exception while transaction was aborted: re-throw it now."; 3674 Runtime::Current()->ThrowTransactionAbortError(self); 3675 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3676 success = false; 3677 } else { 3678 RuntimeStats* global_stats = Runtime::Current()->GetStats(); 3679 RuntimeStats* thread_stats = self->GetStats(); 3680 ++global_stats->class_init_count; 3681 ++thread_stats->class_init_count; 3682 global_stats->class_init_time_ns += (t1 - t0); 3683 thread_stats->class_init_time_ns += (t1 - t0); 3684 // Set the class as initialized except if failed to initialize static fields. 3685 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitialized, self); 3686 if (VLOG_IS_ON(class_linker)) { 3687 std::string temp; 3688 LOG(INFO) << "Initialized class " << klass->GetDescriptor(&temp) << " from " << 3689 klass->GetLocation(); 3690 } 3691 // Opportunistically set static method trampolines to their destination. 3692 FixupStaticTrampolines(klass.Get()); 3693 } 3694 } 3695 return success; 3696} 3697 3698bool ClassLinker::WaitForInitializeClass(Handle<mirror::Class> klass, Thread* self, 3699 ObjectLock<mirror::Class>& lock) 3700 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3701 while (true) { 3702 self->AssertNoPendingException(); 3703 CHECK(!klass->IsInitialized()); 3704 lock.WaitIgnoringInterrupts(); 3705 3706 // When we wake up, repeat the test for init-in-progress. If 3707 // there's an exception pending (only possible if 3708 // we were not using WaitIgnoringInterrupts), bail out. 3709 if (self->IsExceptionPending()) { 3710 WrapExceptionInInitializer(klass); 3711 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3712 return false; 3713 } 3714 // Spurious wakeup? Go back to waiting. 3715 if (klass->GetStatus() == mirror::Class::kStatusInitializing) { 3716 continue; 3717 } 3718 if (klass->GetStatus() == mirror::Class::kStatusVerified && 3719 Runtime::Current()->IsAotCompiler()) { 3720 // Compile time initialization failed. 3721 return false; 3722 } 3723 if (klass->IsErroneous()) { 3724 // The caller wants an exception, but it was thrown in a 3725 // different thread. Synthesize one here. 3726 ThrowNoClassDefFoundError("<clinit> failed for class %s; see exception in other thread", 3727 PrettyDescriptor(klass.Get()).c_str()); 3728 VlogClassInitializationFailure(klass); 3729 return false; 3730 } 3731 if (klass->IsInitialized()) { 3732 return true; 3733 } 3734 LOG(FATAL) << "Unexpected class status. " << PrettyClass(klass.Get()) << " is " 3735 << klass->GetStatus(); 3736 } 3737 UNREACHABLE(); 3738} 3739 3740static bool HasSameSignatureWithDifferentClassLoaders(Thread* self, 3741 Handle<mirror::ArtMethod> method1, 3742 Handle<mirror::ArtMethod> method2, 3743 std::string* error_msg) 3744 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 3745 { 3746 StackHandleScope<1> hs(self); 3747 Handle<mirror::Class> return_type(hs.NewHandle(method1->GetReturnType())); 3748 mirror::Class* other_return_type = method2->GetReturnType(); 3749 // NOTE: return_type.Get() must be sequenced after method2->GetReturnType(). 3750 if (UNLIKELY(other_return_type != return_type.Get())) { 3751 *error_msg = StringPrintf("Return types mismatch: %s(%p) vs %s(%p)", 3752 PrettyClassAndClassLoader(return_type.Get()).c_str(), 3753 return_type.Get(), 3754 PrettyClassAndClassLoader(other_return_type).c_str(), 3755 other_return_type); 3756 return false; 3757 } 3758 } 3759 const DexFile::TypeList* types1 = method1->GetParameterTypeList(); 3760 const DexFile::TypeList* types2 = method2->GetParameterTypeList(); 3761 if (types1 == nullptr) { 3762 if (types2 != nullptr && types2->Size() != 0) { 3763 *error_msg = StringPrintf("Type list mismatch with %s", 3764 PrettyMethod(method2.Get(), true).c_str()); 3765 return false; 3766 } 3767 return true; 3768 } else if (UNLIKELY(types2 == nullptr)) { 3769 if (types1->Size() != 0) { 3770 *error_msg = StringPrintf("Type list mismatch with %s", 3771 PrettyMethod(method2.Get(), true).c_str()); 3772 return false; 3773 } 3774 return true; 3775 } 3776 uint32_t num_types = types1->Size(); 3777 if (UNLIKELY(num_types != types2->Size())) { 3778 *error_msg = StringPrintf("Type list mismatch with %s", 3779 PrettyMethod(method2.Get(), true).c_str()); 3780 return false; 3781 } 3782 for (uint32_t i = 0; i < num_types; ++i) { 3783 StackHandleScope<1> hs(self); 3784 Handle<mirror::Class> param_type(hs.NewHandle( 3785 method1->GetClassFromTypeIndex(types1->GetTypeItem(i).type_idx_, true))); 3786 mirror::Class* other_param_type = 3787 method2->GetClassFromTypeIndex(types2->GetTypeItem(i).type_idx_, true); 3788 // NOTE: param_type.Get() must be sequenced after method2->GetClassFromTypeIndex(...). 3789 if (UNLIKELY(param_type.Get() != other_param_type)) { 3790 *error_msg = StringPrintf("Parameter %u type mismatch: %s(%p) vs %s(%p)", 3791 i, 3792 PrettyClassAndClassLoader(param_type.Get()).c_str(), 3793 param_type.Get(), 3794 PrettyClassAndClassLoader(other_param_type).c_str(), 3795 other_param_type); 3796 return false; 3797 } 3798 } 3799 return true; 3800} 3801 3802 3803bool ClassLinker::ValidateSuperClassDescriptors(Handle<mirror::Class> klass) { 3804 if (klass->IsInterface()) { 3805 return true; 3806 } 3807 // Begin with the methods local to the superclass. 3808 Thread* self = Thread::Current(); 3809 StackHandleScope<2> hs(self); 3810 MutableHandle<mirror::ArtMethod> h_m(hs.NewHandle<mirror::ArtMethod>(nullptr)); 3811 MutableHandle<mirror::ArtMethod> super_h_m(hs.NewHandle<mirror::ArtMethod>(nullptr)); 3812 if (klass->HasSuperClass() && 3813 klass->GetClassLoader() != klass->GetSuperClass()->GetClassLoader()) { 3814 for (int i = klass->GetSuperClass()->GetVTableLength() - 1; i >= 0; --i) { 3815 h_m.Assign(klass->GetVTableEntry(i)); 3816 super_h_m.Assign(klass->GetSuperClass()->GetVTableEntry(i)); 3817 if (h_m.Get() != super_h_m.Get()) { 3818 std::string error_msg; 3819 if (!HasSameSignatureWithDifferentClassLoaders(self, h_m, super_h_m, &error_msg)) { 3820 ThrowLinkageError(klass.Get(), 3821 "Class %s method %s resolves differently in superclass %s: %s", 3822 PrettyDescriptor(klass.Get()).c_str(), 3823 PrettyMethod(h_m.Get()).c_str(), 3824 PrettyDescriptor(klass->GetSuperClass()).c_str(), 3825 error_msg.c_str()); 3826 return false; 3827 } 3828 } 3829 } 3830 } 3831 for (int32_t i = 0; i < klass->GetIfTableCount(); ++i) { 3832 if (klass->GetClassLoader() != klass->GetIfTable()->GetInterface(i)->GetClassLoader()) { 3833 uint32_t num_methods = klass->GetIfTable()->GetInterface(i)->NumVirtualMethods(); 3834 for (uint32_t j = 0; j < num_methods; ++j) { 3835 h_m.Assign(klass->GetIfTable()->GetMethodArray(i)->GetWithoutChecks(j)); 3836 super_h_m.Assign(klass->GetIfTable()->GetInterface(i)->GetVirtualMethod(j)); 3837 if (h_m.Get() != super_h_m.Get()) { 3838 std::string error_msg; 3839 if (!HasSameSignatureWithDifferentClassLoaders(self, h_m, super_h_m, &error_msg)) { 3840 ThrowLinkageError(klass.Get(), 3841 "Class %s method %s resolves differently in interface %s: %s", 3842 PrettyDescriptor(klass.Get()).c_str(), 3843 PrettyMethod(h_m.Get()).c_str(), 3844 PrettyDescriptor(klass->GetIfTable()->GetInterface(i)).c_str(), 3845 error_msg.c_str()); 3846 return false; 3847 } 3848 } 3849 } 3850 } 3851 } 3852 return true; 3853} 3854 3855bool ClassLinker::EnsureInitialized(Thread* self, Handle<mirror::Class> c, bool can_init_fields, 3856 bool can_init_parents) { 3857 DCHECK(c.Get() != nullptr); 3858 if (c->IsInitialized()) { 3859 EnsurePreverifiedMethods(c); 3860 return true; 3861 } 3862 const bool success = InitializeClass(self, c, can_init_fields, can_init_parents); 3863 if (!success) { 3864 if (can_init_fields && can_init_parents) { 3865 CHECK(self->IsExceptionPending()) << PrettyClass(c.Get()); 3866 } 3867 } else { 3868 self->AssertNoPendingException(); 3869 } 3870 return success; 3871} 3872 3873void ClassLinker::FixupTemporaryDeclaringClass(mirror::Class* temp_class, mirror::Class* new_class) { 3874 ArtField* fields = new_class->GetIFields(); 3875 for (size_t i = 0, count = new_class->NumInstanceFields(); i < count; i++) { 3876 if (fields[i].GetDeclaringClass() == temp_class) { 3877 fields[i].SetDeclaringClass(new_class); 3878 } 3879 } 3880 3881 fields = new_class->GetSFields(); 3882 for (size_t i = 0, count = new_class->NumStaticFields(); i < count; i++) { 3883 if (fields[i].GetDeclaringClass() == temp_class) { 3884 fields[i].SetDeclaringClass(new_class); 3885 } 3886 } 3887 3888 mirror::ObjectArray<mirror::ArtMethod>* methods = new_class->GetDirectMethods(); 3889 if (methods != nullptr) { 3890 for (int index = 0; index < methods->GetLength(); index ++) { 3891 if (methods->Get(index)->GetDeclaringClass() == temp_class) { 3892 methods->Get(index)->SetDeclaringClass(new_class); 3893 } 3894 } 3895 } 3896 3897 methods = new_class->GetVirtualMethods(); 3898 if (methods != nullptr) { 3899 for (int index = 0; index < methods->GetLength(); index ++) { 3900 if (methods->Get(index)->GetDeclaringClass() == temp_class) { 3901 methods->Get(index)->SetDeclaringClass(new_class); 3902 } 3903 } 3904 } 3905} 3906 3907bool ClassLinker::LinkClass(Thread* self, const char* descriptor, Handle<mirror::Class> klass, 3908 Handle<mirror::ObjectArray<mirror::Class>> interfaces, 3909 mirror::Class** new_class) { 3910 CHECK_EQ(mirror::Class::kStatusLoaded, klass->GetStatus()); 3911 3912 if (!LinkSuperClass(klass)) { 3913 return false; 3914 } 3915 StackHandleScope<mirror::Class::kImtSize> imt_handle_scope( 3916 self, Runtime::Current()->GetImtUnimplementedMethod()); 3917 if (!LinkMethods(self, klass, interfaces, &imt_handle_scope)) { 3918 return false; 3919 } 3920 if (!LinkInstanceFields(self, klass)) { 3921 return false; 3922 } 3923 size_t class_size; 3924 if (!LinkStaticFields(self, klass, &class_size)) { 3925 return false; 3926 } 3927 CreateReferenceInstanceOffsets(klass); 3928 CHECK_EQ(mirror::Class::kStatusLoaded, klass->GetStatus()); 3929 3930 if (!klass->IsTemp() || (!init_done_ && klass->GetClassSize() == class_size)) { 3931 // We don't need to retire this class as it has no embedded tables or it was created the 3932 // correct size during class linker initialization. 3933 CHECK_EQ(klass->GetClassSize(), class_size) << PrettyDescriptor(klass.Get()); 3934 3935 if (klass->ShouldHaveEmbeddedImtAndVTable()) { 3936 klass->PopulateEmbeddedImtAndVTable(&imt_handle_scope); 3937 } 3938 3939 // This will notify waiters on klass that saw the not yet resolved 3940 // class in the class_table_ during EnsureResolved. 3941 mirror::Class::SetStatus(klass, mirror::Class::kStatusResolved, self); 3942 *new_class = klass.Get(); 3943 } else { 3944 CHECK(!klass->IsResolved()); 3945 // Retire the temporary class and create the correctly sized resolved class. 3946 *new_class = klass->CopyOf(self, class_size, &imt_handle_scope); 3947 if (UNLIKELY(*new_class == nullptr)) { 3948 CHECK(self->IsExceptionPending()); // Expect an OOME. 3949 mirror::Class::SetStatus(klass, mirror::Class::kStatusError, self); 3950 return false; 3951 } 3952 3953 CHECK_EQ((*new_class)->GetClassSize(), class_size); 3954 StackHandleScope<1> hs(self); 3955 auto new_class_h = hs.NewHandleWrapper<mirror::Class>(new_class); 3956 ObjectLock<mirror::Class> lock(self, new_class_h); 3957 3958 FixupTemporaryDeclaringClass(klass.Get(), new_class_h.Get()); 3959 3960 mirror::Class* existing = UpdateClass(descriptor, new_class_h.Get(), 3961 ComputeModifiedUtf8Hash(descriptor)); 3962 CHECK(existing == nullptr || existing == klass.Get()); 3963 3964 // This will notify waiters on temp class that saw the not yet resolved class in the 3965 // class_table_ during EnsureResolved. 3966 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetired, self); 3967 3968 CHECK_EQ(new_class_h->GetStatus(), mirror::Class::kStatusResolving); 3969 // This will notify waiters on new_class that saw the not yet resolved 3970 // class in the class_table_ during EnsureResolved. 3971 mirror::Class::SetStatus(new_class_h, mirror::Class::kStatusResolved, self); 3972 } 3973 return true; 3974} 3975 3976static void CountMethodsAndFields(ClassDataItemIterator& dex_data, 3977 size_t* virtual_methods, 3978 size_t* direct_methods, 3979 size_t* static_fields, 3980 size_t* instance_fields) { 3981 *virtual_methods = *direct_methods = *static_fields = *instance_fields = 0; 3982 3983 while (dex_data.HasNextStaticField()) { 3984 dex_data.Next(); 3985 (*static_fields)++; 3986 } 3987 while (dex_data.HasNextInstanceField()) { 3988 dex_data.Next(); 3989 (*instance_fields)++; 3990 } 3991 while (dex_data.HasNextDirectMethod()) { 3992 (*direct_methods)++; 3993 dex_data.Next(); 3994 } 3995 while (dex_data.HasNextVirtualMethod()) { 3996 (*virtual_methods)++; 3997 dex_data.Next(); 3998 } 3999 DCHECK(!dex_data.HasNext()); 4000} 4001 4002static void DumpClass(std::ostream& os, 4003 const DexFile& dex_file, const DexFile::ClassDef& dex_class_def, 4004 const char* suffix) { 4005 ClassDataItemIterator dex_data(dex_file, dex_file.GetClassData(dex_class_def)); 4006 os << dex_file.GetClassDescriptor(dex_class_def) << suffix << ":\n"; 4007 os << " Static fields:\n"; 4008 while (dex_data.HasNextStaticField()) { 4009 const DexFile::FieldId& id = dex_file.GetFieldId(dex_data.GetMemberIndex()); 4010 os << " " << dex_file.GetFieldTypeDescriptor(id) << " " << dex_file.GetFieldName(id) << "\n"; 4011 dex_data.Next(); 4012 } 4013 os << " Instance fields:\n"; 4014 while (dex_data.HasNextInstanceField()) { 4015 const DexFile::FieldId& id = dex_file.GetFieldId(dex_data.GetMemberIndex()); 4016 os << " " << dex_file.GetFieldTypeDescriptor(id) << " " << dex_file.GetFieldName(id) << "\n"; 4017 dex_data.Next(); 4018 } 4019 os << " Direct methods:\n"; 4020 while (dex_data.HasNextDirectMethod()) { 4021 const DexFile::MethodId& id = dex_file.GetMethodId(dex_data.GetMemberIndex()); 4022 os << " " << dex_file.GetMethodName(id) << dex_file.GetMethodSignature(id).ToString() << "\n"; 4023 dex_data.Next(); 4024 } 4025 os << " Virtual methods:\n"; 4026 while (dex_data.HasNextVirtualMethod()) { 4027 const DexFile::MethodId& id = dex_file.GetMethodId(dex_data.GetMemberIndex()); 4028 os << " " << dex_file.GetMethodName(id) << dex_file.GetMethodSignature(id).ToString() << "\n"; 4029 dex_data.Next(); 4030 } 4031} 4032 4033static std::string DumpClasses(const DexFile& dex_file1, const DexFile::ClassDef& dex_class_def1, 4034 const DexFile& dex_file2, const DexFile::ClassDef& dex_class_def2) { 4035 std::ostringstream os; 4036 DumpClass(os, dex_file1, dex_class_def1, " (Compile time)"); 4037 DumpClass(os, dex_file2, dex_class_def2, " (Runtime)"); 4038 return os.str(); 4039} 4040 4041 4042// Very simple structural check on whether the classes match. Only compares the number of 4043// methods and fields. 4044static bool SimpleStructuralCheck(const DexFile& dex_file1, const DexFile::ClassDef& dex_class_def1, 4045 const DexFile& dex_file2, const DexFile::ClassDef& dex_class_def2, 4046 std::string* error_msg) { 4047 ClassDataItemIterator dex_data1(dex_file1, dex_file1.GetClassData(dex_class_def1)); 4048 ClassDataItemIterator dex_data2(dex_file2, dex_file2.GetClassData(dex_class_def2)); 4049 4050 // Counters for current dex file. 4051 size_t dex_virtual_methods1, dex_direct_methods1, dex_static_fields1, dex_instance_fields1; 4052 CountMethodsAndFields(dex_data1, &dex_virtual_methods1, &dex_direct_methods1, &dex_static_fields1, 4053 &dex_instance_fields1); 4054 // Counters for compile-time dex file. 4055 size_t dex_virtual_methods2, dex_direct_methods2, dex_static_fields2, dex_instance_fields2; 4056 CountMethodsAndFields(dex_data2, &dex_virtual_methods2, &dex_direct_methods2, &dex_static_fields2, 4057 &dex_instance_fields2); 4058 4059 if (dex_virtual_methods1 != dex_virtual_methods2) { 4060 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 4061 *error_msg = StringPrintf("Virtual method count off: %zu vs %zu\n%s", dex_virtual_methods1, 4062 dex_virtual_methods2, class_dump.c_str()); 4063 return false; 4064 } 4065 if (dex_direct_methods1 != dex_direct_methods2) { 4066 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 4067 *error_msg = StringPrintf("Direct method count off: %zu vs %zu\n%s", dex_direct_methods1, 4068 dex_direct_methods2, class_dump.c_str()); 4069 return false; 4070 } 4071 if (dex_static_fields1 != dex_static_fields2) { 4072 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 4073 *error_msg = StringPrintf("Static field count off: %zu vs %zu\n%s", dex_static_fields1, 4074 dex_static_fields2, class_dump.c_str()); 4075 return false; 4076 } 4077 if (dex_instance_fields1 != dex_instance_fields2) { 4078 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2); 4079 *error_msg = StringPrintf("Instance field count off: %zu vs %zu\n%s", dex_instance_fields1, 4080 dex_instance_fields2, class_dump.c_str()); 4081 return false; 4082 } 4083 4084 return true; 4085} 4086 4087// Checks whether a the super-class changed from what we had at compile-time. This would 4088// invalidate quickening. 4089static bool CheckSuperClassChange(Handle<mirror::Class> klass, 4090 const DexFile& dex_file, 4091 const DexFile::ClassDef& class_def, 4092 mirror::Class* super_class) 4093 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4094 // Check for unexpected changes in the superclass. 4095 // Quick check 1) is the super_class class-loader the boot class loader? This always has 4096 // precedence. 4097 if (super_class->GetClassLoader() != nullptr && 4098 // Quick check 2) different dex cache? Breaks can only occur for different dex files, 4099 // which is implied by different dex cache. 4100 klass->GetDexCache() != super_class->GetDexCache()) { 4101 // Now comes the expensive part: things can be broken if (a) the klass' dex file has a 4102 // definition for the super-class, and (b) the files are in separate oat files. The oat files 4103 // are referenced from the dex file, so do (b) first. Only relevant if we have oat files. 4104 const OatDexFile* class_oat_dex_file = dex_file.GetOatDexFile(); 4105 const OatFile* class_oat_file = nullptr; 4106 if (class_oat_dex_file != nullptr) { 4107 class_oat_file = class_oat_dex_file->GetOatFile(); 4108 } 4109 4110 if (class_oat_file != nullptr) { 4111 const OatDexFile* loaded_super_oat_dex_file = super_class->GetDexFile().GetOatDexFile(); 4112 const OatFile* loaded_super_oat_file = nullptr; 4113 if (loaded_super_oat_dex_file != nullptr) { 4114 loaded_super_oat_file = loaded_super_oat_dex_file->GetOatFile(); 4115 } 4116 4117 if (loaded_super_oat_file != nullptr && class_oat_file != loaded_super_oat_file) { 4118 // Now check (a). 4119 const DexFile::ClassDef* super_class_def = dex_file.FindClassDef(class_def.superclass_idx_); 4120 if (super_class_def != nullptr) { 4121 // Uh-oh, we found something. Do our check. 4122 std::string error_msg; 4123 if (!SimpleStructuralCheck(dex_file, *super_class_def, 4124 super_class->GetDexFile(), *super_class->GetClassDef(), 4125 &error_msg)) { 4126 // Print a warning to the log. This exception might be caught, e.g., as common in test 4127 // drivers. When the class is later tried to be used, we re-throw a new instance, as we 4128 // only save the type of the exception. 4129 LOG(WARNING) << "Incompatible structural change detected: " << 4130 StringPrintf( 4131 "Structural change of %s is hazardous (%s at compile time, %s at runtime): %s", 4132 PrettyType(super_class_def->class_idx_, dex_file).c_str(), 4133 class_oat_file->GetLocation().c_str(), 4134 loaded_super_oat_file->GetLocation().c_str(), 4135 error_msg.c_str()); 4136 ThrowIncompatibleClassChangeError(klass.Get(), 4137 "Structural change of %s is hazardous (%s at compile time, %s at runtime): %s", 4138 PrettyType(super_class_def->class_idx_, dex_file).c_str(), 4139 class_oat_file->GetLocation().c_str(), 4140 loaded_super_oat_file->GetLocation().c_str(), 4141 error_msg.c_str()); 4142 return false; 4143 } 4144 } 4145 } 4146 } 4147 } 4148 return true; 4149} 4150 4151bool ClassLinker::LoadSuperAndInterfaces(Handle<mirror::Class> klass, const DexFile& dex_file) { 4152 CHECK_EQ(mirror::Class::kStatusIdx, klass->GetStatus()); 4153 const DexFile::ClassDef& class_def = dex_file.GetClassDef(klass->GetDexClassDefIndex()); 4154 uint16_t super_class_idx = class_def.superclass_idx_; 4155 if (super_class_idx != DexFile::kDexNoIndex16) { 4156 mirror::Class* super_class = ResolveType(dex_file, super_class_idx, klass.Get()); 4157 if (super_class == nullptr) { 4158 DCHECK(Thread::Current()->IsExceptionPending()); 4159 return false; 4160 } 4161 // Verify 4162 if (!klass->CanAccess(super_class)) { 4163 ThrowIllegalAccessError(klass.Get(), "Class %s extended by class %s is inaccessible", 4164 PrettyDescriptor(super_class).c_str(), 4165 PrettyDescriptor(klass.Get()).c_str()); 4166 return false; 4167 } 4168 CHECK(super_class->IsResolved()); 4169 klass->SetSuperClass(super_class); 4170 4171 if (!CheckSuperClassChange(klass, dex_file, class_def, super_class)) { 4172 DCHECK(Thread::Current()->IsExceptionPending()); 4173 return false; 4174 } 4175 } 4176 const DexFile::TypeList* interfaces = dex_file.GetInterfacesList(class_def); 4177 if (interfaces != nullptr) { 4178 for (size_t i = 0; i < interfaces->Size(); i++) { 4179 uint16_t idx = interfaces->GetTypeItem(i).type_idx_; 4180 mirror::Class* interface = ResolveType(dex_file, idx, klass.Get()); 4181 if (interface == nullptr) { 4182 DCHECK(Thread::Current()->IsExceptionPending()); 4183 return false; 4184 } 4185 // Verify 4186 if (!klass->CanAccess(interface)) { 4187 // TODO: the RI seemed to ignore this in my testing. 4188 ThrowIllegalAccessError(klass.Get(), "Interface %s implemented by class %s is inaccessible", 4189 PrettyDescriptor(interface).c_str(), 4190 PrettyDescriptor(klass.Get()).c_str()); 4191 return false; 4192 } 4193 } 4194 } 4195 // Mark the class as loaded. 4196 mirror::Class::SetStatus(klass, mirror::Class::kStatusLoaded, nullptr); 4197 return true; 4198} 4199 4200bool ClassLinker::LinkSuperClass(Handle<mirror::Class> klass) { 4201 CHECK(!klass->IsPrimitive()); 4202 mirror::Class* super = klass->GetSuperClass(); 4203 if (klass.Get() == GetClassRoot(kJavaLangObject)) { 4204 if (super != nullptr) { 4205 ThrowClassFormatError(klass.Get(), "java.lang.Object must not have a superclass"); 4206 return false; 4207 } 4208 return true; 4209 } 4210 if (super == nullptr) { 4211 ThrowLinkageError(klass.Get(), "No superclass defined for class %s", 4212 PrettyDescriptor(klass.Get()).c_str()); 4213 return false; 4214 } 4215 // Verify 4216 if (super->IsFinal() || super->IsInterface()) { 4217 ThrowIncompatibleClassChangeError(klass.Get(), "Superclass %s of %s is %s", 4218 PrettyDescriptor(super).c_str(), 4219 PrettyDescriptor(klass.Get()).c_str(), 4220 super->IsFinal() ? "declared final" : "an interface"); 4221 return false; 4222 } 4223 if (!klass->CanAccess(super)) { 4224 ThrowIllegalAccessError(klass.Get(), "Superclass %s is inaccessible to class %s", 4225 PrettyDescriptor(super).c_str(), 4226 PrettyDescriptor(klass.Get()).c_str()); 4227 return false; 4228 } 4229 4230 // Inherit kAccClassIsFinalizable from the superclass in case this 4231 // class doesn't override finalize. 4232 if (super->IsFinalizable()) { 4233 klass->SetFinalizable(); 4234 } 4235 4236 // Inherit reference flags (if any) from the superclass. 4237 int reference_flags = (super->GetAccessFlags() & kAccReferenceFlagsMask); 4238 if (reference_flags != 0) { 4239 klass->SetAccessFlags(klass->GetAccessFlags() | reference_flags); 4240 } 4241 // Disallow custom direct subclasses of java.lang.ref.Reference. 4242 if (init_done_ && super == GetClassRoot(kJavaLangRefReference)) { 4243 ThrowLinkageError(klass.Get(), 4244 "Class %s attempts to subclass java.lang.ref.Reference, which is not allowed", 4245 PrettyDescriptor(klass.Get()).c_str()); 4246 return false; 4247 } 4248 4249 if (kIsDebugBuild) { 4250 // Ensure super classes are fully resolved prior to resolving fields.. 4251 while (super != nullptr) { 4252 CHECK(super->IsResolved()); 4253 super = super->GetSuperClass(); 4254 } 4255 } 4256 return true; 4257} 4258 4259// Populate the class vtable and itable. Compute return type indices. 4260bool ClassLinker::LinkMethods(Thread* self, Handle<mirror::Class> klass, 4261 Handle<mirror::ObjectArray<mirror::Class>> interfaces, 4262 StackHandleScope<mirror::Class::kImtSize>* out_imt) { 4263 self->AllowThreadSuspension(); 4264 if (klass->IsInterface()) { 4265 // No vtable. 4266 size_t count = klass->NumVirtualMethods(); 4267 if (!IsUint<16>(count)) { 4268 ThrowClassFormatError(klass.Get(), "Too many methods on interface: %zd", count); 4269 return false; 4270 } 4271 for (size_t i = 0; i < count; ++i) { 4272 klass->GetVirtualMethodDuringLinking(i)->SetMethodIndex(i); 4273 } 4274 } else if (!LinkVirtualMethods(self, klass)) { // Link virtual methods first. 4275 return false; 4276 } 4277 return LinkInterfaceMethods(self, klass, interfaces, out_imt); // Link interface method last. 4278} 4279 4280// Comparator for name and signature of a method, used in finding overriding methods. Implementation 4281// avoids the use of handles, if it didn't then rather than compare dex files we could compare dex 4282// caches in the implementation below. 4283class MethodNameAndSignatureComparator FINAL : public ValueObject { 4284 public: 4285 explicit MethodNameAndSignatureComparator(mirror::ArtMethod* method) 4286 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) : 4287 dex_file_(method->GetDexFile()), mid_(&dex_file_->GetMethodId(method->GetDexMethodIndex())), 4288 name_(nullptr), name_len_(0) { 4289 DCHECK(!method->IsProxyMethod()) << PrettyMethod(method); 4290 } 4291 4292 const char* GetName() { 4293 if (name_ == nullptr) { 4294 name_ = dex_file_->StringDataAndUtf16LengthByIdx(mid_->name_idx_, &name_len_); 4295 } 4296 return name_; 4297 } 4298 4299 bool HasSameNameAndSignature(mirror::ArtMethod* other) 4300 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4301 DCHECK(!other->IsProxyMethod()) << PrettyMethod(other); 4302 const DexFile* other_dex_file = other->GetDexFile(); 4303 const DexFile::MethodId& other_mid = other_dex_file->GetMethodId(other->GetDexMethodIndex()); 4304 if (dex_file_ == other_dex_file) { 4305 return mid_->name_idx_ == other_mid.name_idx_ && mid_->proto_idx_ == other_mid.proto_idx_; 4306 } 4307 GetName(); // Only used to make sure its calculated. 4308 uint32_t other_name_len; 4309 const char* other_name = other_dex_file->StringDataAndUtf16LengthByIdx(other_mid.name_idx_, 4310 &other_name_len); 4311 if (name_len_ != other_name_len || strcmp(name_, other_name) != 0) { 4312 return false; 4313 } 4314 return dex_file_->GetMethodSignature(*mid_) == other_dex_file->GetMethodSignature(other_mid); 4315 } 4316 4317 private: 4318 // Dex file for the method to compare against. 4319 const DexFile* const dex_file_; 4320 // MethodId for the method to compare against. 4321 const DexFile::MethodId* const mid_; 4322 // Lazily computed name from the dex file's strings. 4323 const char* name_; 4324 // Lazily computed name length. 4325 uint32_t name_len_; 4326}; 4327 4328class LinkVirtualHashTable { 4329 public: 4330 LinkVirtualHashTable(Handle<mirror::Class> klass, size_t hash_size, uint32_t* hash_table) 4331 : klass_(klass), hash_size_(hash_size), hash_table_(hash_table) { 4332 std::fill(hash_table_, hash_table_ + hash_size_, invalid_index_); 4333 } 4334 void Add(uint32_t virtual_method_index) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4335 mirror::ArtMethod* local_method = klass_->GetVirtualMethodDuringLinking(virtual_method_index); 4336 const char* name = local_method->GetName(); 4337 uint32_t hash = ComputeModifiedUtf8Hash(name); 4338 uint32_t index = hash % hash_size_; 4339 // Linear probe until we have an empty slot. 4340 while (hash_table_[index] != invalid_index_) { 4341 if (++index == hash_size_) { 4342 index = 0; 4343 } 4344 } 4345 hash_table_[index] = virtual_method_index; 4346 } 4347 uint32_t FindAndRemove(MethodNameAndSignatureComparator* comparator) 4348 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4349 const char* name = comparator->GetName(); 4350 uint32_t hash = ComputeModifiedUtf8Hash(name); 4351 size_t index = hash % hash_size_; 4352 while (true) { 4353 const uint32_t value = hash_table_[index]; 4354 // Since linear probe makes continuous blocks, hitting an invalid index means we are done 4355 // the block and can safely assume not found. 4356 if (value == invalid_index_) { 4357 break; 4358 } 4359 if (value != removed_index_) { // This signifies not already overriden. 4360 mirror::ArtMethod* virtual_method = 4361 klass_->GetVirtualMethodDuringLinking(value); 4362 if (comparator->HasSameNameAndSignature(virtual_method->GetInterfaceMethodIfProxy())) { 4363 hash_table_[index] = removed_index_; 4364 return value; 4365 } 4366 } 4367 if (++index == hash_size_) { 4368 index = 0; 4369 } 4370 } 4371 return GetNotFoundIndex(); 4372 } 4373 static uint32_t GetNotFoundIndex() { 4374 return invalid_index_; 4375 } 4376 4377 private: 4378 static const uint32_t invalid_index_; 4379 static const uint32_t removed_index_; 4380 4381 Handle<mirror::Class> klass_; 4382 const size_t hash_size_; 4383 uint32_t* const hash_table_; 4384}; 4385 4386const uint32_t LinkVirtualHashTable::invalid_index_ = std::numeric_limits<uint32_t>::max(); 4387const uint32_t LinkVirtualHashTable::removed_index_ = std::numeric_limits<uint32_t>::max() - 1; 4388 4389bool ClassLinker::LinkVirtualMethods(Thread* self, Handle<mirror::Class> klass) { 4390 const size_t num_virtual_methods = klass->NumVirtualMethods(); 4391 if (klass->HasSuperClass()) { 4392 const size_t super_vtable_length = klass->GetSuperClass()->GetVTableLength(); 4393 const size_t max_count = num_virtual_methods + super_vtable_length; 4394 StackHandleScope<2> hs(self); 4395 Handle<mirror::Class> super_class(hs.NewHandle(klass->GetSuperClass())); 4396 MutableHandle<mirror::ObjectArray<mirror::ArtMethod>> vtable; 4397 if (super_class->ShouldHaveEmbeddedImtAndVTable()) { 4398 vtable = hs.NewHandle(AllocArtMethodArray(self, max_count)); 4399 if (UNLIKELY(vtable.Get() == nullptr)) { 4400 CHECK(self->IsExceptionPending()); // OOME. 4401 return false; 4402 } 4403 for (size_t i = 0; i < super_vtable_length; i++) { 4404 vtable->SetWithoutChecks<false>(i, super_class->GetEmbeddedVTableEntry(i)); 4405 } 4406 if (num_virtual_methods == 0) { 4407 klass->SetVTable(vtable.Get()); 4408 return true; 4409 } 4410 } else { 4411 mirror::ObjectArray<mirror::ArtMethod>* super_vtable = super_class->GetVTable(); 4412 CHECK(super_vtable != nullptr) << PrettyClass(super_class.Get()); 4413 if (num_virtual_methods == 0) { 4414 klass->SetVTable(super_vtable); 4415 return true; 4416 } 4417 vtable = hs.NewHandle(super_vtable->CopyOf(self, max_count)); 4418 if (UNLIKELY(vtable.Get() == nullptr)) { 4419 CHECK(self->IsExceptionPending()); // OOME. 4420 return false; 4421 } 4422 } 4423 // How the algorithm works: 4424 // 1. Populate hash table by adding num_virtual_methods from klass. The values in the hash 4425 // table are: invalid_index for unused slots, index super_vtable_length + i for a virtual 4426 // method which has not been matched to a vtable method, and j if the virtual method at the 4427 // index overrode the super virtual method at index j. 4428 // 2. Loop through super virtual methods, if they overwrite, update hash table to j 4429 // (j < super_vtable_length) to avoid redundant checks. (TODO maybe use this info for reducing 4430 // the need for the initial vtable which we later shrink back down). 4431 // 3. Add non overridden methods to the end of the vtable. 4432 static constexpr size_t kMaxStackHash = 250; 4433 const size_t hash_table_size = num_virtual_methods * 3; 4434 uint32_t* hash_table_ptr; 4435 std::unique_ptr<uint32_t[]> hash_heap_storage; 4436 if (hash_table_size <= kMaxStackHash) { 4437 hash_table_ptr = reinterpret_cast<uint32_t*>( 4438 alloca(hash_table_size * sizeof(*hash_table_ptr))); 4439 } else { 4440 hash_heap_storage.reset(new uint32_t[hash_table_size]); 4441 hash_table_ptr = hash_heap_storage.get(); 4442 } 4443 LinkVirtualHashTable hash_table(klass, hash_table_size, hash_table_ptr); 4444 // Add virtual methods to the hash table. 4445 for (size_t i = 0; i < num_virtual_methods; ++i) { 4446 hash_table.Add(i); 4447 } 4448 // Loop through each super vtable method and see if they are overriden by a method we added to 4449 // the hash table. 4450 for (size_t j = 0; j < super_vtable_length; ++j) { 4451 // Search the hash table to see if we are overidden by any method. 4452 mirror::ArtMethod* super_method = vtable->GetWithoutChecks(j); 4453 MethodNameAndSignatureComparator super_method_name_comparator( 4454 super_method->GetInterfaceMethodIfProxy()); 4455 uint32_t hash_index = hash_table.FindAndRemove(&super_method_name_comparator); 4456 if (hash_index != hash_table.GetNotFoundIndex()) { 4457 mirror::ArtMethod* virtual_method = klass->GetVirtualMethodDuringLinking(hash_index); 4458 if (klass->CanAccessMember(super_method->GetDeclaringClass(), 4459 super_method->GetAccessFlags())) { 4460 if (super_method->IsFinal()) { 4461 ThrowLinkageError(klass.Get(), "Method %s overrides final method in class %s", 4462 PrettyMethod(virtual_method).c_str(), 4463 super_method->GetDeclaringClassDescriptor()); 4464 return false; 4465 } 4466 vtable->SetWithoutChecks<false>(j, virtual_method); 4467 virtual_method->SetMethodIndex(j); 4468 } else { 4469 LOG(WARNING) << "Before Android 4.1, method " << PrettyMethod(virtual_method) 4470 << " would have incorrectly overridden the package-private method in " 4471 << PrettyDescriptor(super_method->GetDeclaringClassDescriptor()); 4472 } 4473 } 4474 } 4475 // Add the non overridden methods at the end. 4476 size_t actual_count = super_vtable_length; 4477 for (size_t i = 0; i < num_virtual_methods; ++i) { 4478 mirror::ArtMethod* local_method = klass->GetVirtualMethodDuringLinking(i); 4479 size_t method_idx = local_method->GetMethodIndexDuringLinking(); 4480 if (method_idx < super_vtable_length && 4481 local_method == vtable->GetWithoutChecks(method_idx)) { 4482 continue; 4483 } 4484 vtable->SetWithoutChecks<false>(actual_count, local_method); 4485 local_method->SetMethodIndex(actual_count); 4486 ++actual_count; 4487 } 4488 if (!IsUint<16>(actual_count)) { 4489 ThrowClassFormatError(klass.Get(), "Too many methods defined on class: %zd", actual_count); 4490 return false; 4491 } 4492 // Shrink vtable if possible 4493 CHECK_LE(actual_count, max_count); 4494 if (actual_count < max_count) { 4495 vtable.Assign(vtable->CopyOf(self, actual_count)); 4496 if (UNLIKELY(vtable.Get() == nullptr)) { 4497 CHECK(self->IsExceptionPending()); // OOME. 4498 return false; 4499 } 4500 } 4501 klass->SetVTable(vtable.Get()); 4502 } else { 4503 CHECK_EQ(klass.Get(), GetClassRoot(kJavaLangObject)); 4504 if (!IsUint<16>(num_virtual_methods)) { 4505 ThrowClassFormatError(klass.Get(), "Too many methods: %d", 4506 static_cast<int>(num_virtual_methods)); 4507 return false; 4508 } 4509 mirror::ObjectArray<mirror::ArtMethod>* vtable = AllocArtMethodArray(self, num_virtual_methods); 4510 if (UNLIKELY(vtable == nullptr)) { 4511 CHECK(self->IsExceptionPending()); // OOME. 4512 return false; 4513 } 4514 for (size_t i = 0; i < num_virtual_methods; ++i) { 4515 mirror::ArtMethod* virtual_method = klass->GetVirtualMethodDuringLinking(i); 4516 vtable->SetWithoutChecks<false>(i, virtual_method); 4517 virtual_method->SetMethodIndex(i & 0xFFFF); 4518 } 4519 klass->SetVTable(vtable); 4520 } 4521 return true; 4522} 4523 4524bool ClassLinker::LinkInterfaceMethods(Thread* self, Handle<mirror::Class> klass, 4525 Handle<mirror::ObjectArray<mirror::Class>> interfaces, 4526 StackHandleScope<mirror::Class::kImtSize>* out_imt) { 4527 StackHandleScope<3> hs(self); 4528 Runtime* const runtime = Runtime::Current(); 4529 const bool has_superclass = klass->HasSuperClass(); 4530 const size_t super_ifcount = has_superclass ? klass->GetSuperClass()->GetIfTableCount() : 0U; 4531 const bool have_interfaces = interfaces.Get() != nullptr; 4532 const size_t num_interfaces = 4533 have_interfaces ? interfaces->GetLength() : klass->NumDirectInterfaces(); 4534 if (num_interfaces == 0) { 4535 if (super_ifcount == 0) { 4536 // Class implements no interfaces. 4537 DCHECK_EQ(klass->GetIfTableCount(), 0); 4538 DCHECK(klass->GetIfTable() == nullptr); 4539 return true; 4540 } 4541 // Class implements same interfaces as parent, are any of these not marker interfaces? 4542 bool has_non_marker_interface = false; 4543 mirror::IfTable* super_iftable = klass->GetSuperClass()->GetIfTable(); 4544 for (size_t i = 0; i < super_ifcount; ++i) { 4545 if (super_iftable->GetMethodArrayCount(i) > 0) { 4546 has_non_marker_interface = true; 4547 break; 4548 } 4549 } 4550 // Class just inherits marker interfaces from parent so recycle parent's iftable. 4551 if (!has_non_marker_interface) { 4552 klass->SetIfTable(super_iftable); 4553 return true; 4554 } 4555 } 4556 size_t ifcount = super_ifcount + num_interfaces; 4557 for (size_t i = 0; i < num_interfaces; i++) { 4558 mirror::Class* interface = have_interfaces ? 4559 interfaces->GetWithoutChecks(i) : mirror::Class::GetDirectInterface(self, klass, i); 4560 DCHECK(interface != nullptr); 4561 if (UNLIKELY(!interface->IsInterface())) { 4562 std::string temp; 4563 ThrowIncompatibleClassChangeError(klass.Get(), "Class %s implements non-interface class %s", 4564 PrettyDescriptor(klass.Get()).c_str(), 4565 PrettyDescriptor(interface->GetDescriptor(&temp)).c_str()); 4566 return false; 4567 } 4568 ifcount += interface->GetIfTableCount(); 4569 } 4570 MutableHandle<mirror::IfTable> iftable(hs.NewHandle(AllocIfTable(self, ifcount))); 4571 if (UNLIKELY(iftable.Get() == nullptr)) { 4572 CHECK(self->IsExceptionPending()); // OOME. 4573 return false; 4574 } 4575 if (super_ifcount != 0) { 4576 mirror::IfTable* super_iftable = klass->GetSuperClass()->GetIfTable(); 4577 for (size_t i = 0; i < super_ifcount; i++) { 4578 mirror::Class* super_interface = super_iftable->GetInterface(i); 4579 iftable->SetInterface(i, super_interface); 4580 } 4581 } 4582 self->AllowThreadSuspension(); 4583 // Flatten the interface inheritance hierarchy. 4584 size_t idx = super_ifcount; 4585 for (size_t i = 0; i < num_interfaces; i++) { 4586 mirror::Class* interface = have_interfaces ? interfaces->Get(i) : 4587 mirror::Class::GetDirectInterface(self, klass, i); 4588 // Check if interface is already in iftable 4589 bool duplicate = false; 4590 for (size_t j = 0; j < idx; j++) { 4591 mirror::Class* existing_interface = iftable->GetInterface(j); 4592 if (existing_interface == interface) { 4593 duplicate = true; 4594 break; 4595 } 4596 } 4597 if (!duplicate) { 4598 // Add this non-duplicate interface. 4599 iftable->SetInterface(idx++, interface); 4600 // Add this interface's non-duplicate super-interfaces. 4601 for (int32_t j = 0; j < interface->GetIfTableCount(); j++) { 4602 mirror::Class* super_interface = interface->GetIfTable()->GetInterface(j); 4603 bool super_duplicate = false; 4604 for (size_t k = 0; k < idx; k++) { 4605 mirror::Class* existing_interface = iftable->GetInterface(k); 4606 if (existing_interface == super_interface) { 4607 super_duplicate = true; 4608 break; 4609 } 4610 } 4611 if (!super_duplicate) { 4612 iftable->SetInterface(idx++, super_interface); 4613 } 4614 } 4615 } 4616 } 4617 self->AllowThreadSuspension(); 4618 // Shrink iftable in case duplicates were found 4619 if (idx < ifcount) { 4620 DCHECK_NE(num_interfaces, 0U); 4621 iftable.Assign(down_cast<mirror::IfTable*>(iftable->CopyOf(self, idx * mirror::IfTable::kMax))); 4622 if (UNLIKELY(iftable.Get() == nullptr)) { 4623 CHECK(self->IsExceptionPending()); // OOME. 4624 return false; 4625 } 4626 ifcount = idx; 4627 } else { 4628 DCHECK_EQ(idx, ifcount); 4629 } 4630 klass->SetIfTable(iftable.Get()); 4631 // If we're an interface, we don't need the vtable pointers, so we're done. 4632 if (klass->IsInterface()) { 4633 return true; 4634 } 4635 size_t miranda_list_size = 0; 4636 size_t max_miranda_methods = 0; // The max size of miranda_list. 4637 for (size_t i = 0; i < ifcount; ++i) { 4638 max_miranda_methods += iftable->GetInterface(i)->NumVirtualMethods(); 4639 } 4640 MutableHandle<mirror::ObjectArray<mirror::ArtMethod>> 4641 miranda_list(hs.NewHandle(AllocArtMethodArray(self, max_miranda_methods))); 4642 MutableHandle<mirror::ObjectArray<mirror::ArtMethod>> vtable( 4643 hs.NewHandle(klass->GetVTableDuringLinking())); 4644 // Copy the IMT from the super class if possible. 4645 bool extend_super_iftable = false; 4646 if (has_superclass) { 4647 mirror::Class* super_class = klass->GetSuperClass(); 4648 extend_super_iftable = true; 4649 if (super_class->ShouldHaveEmbeddedImtAndVTable()) { 4650 for (size_t i = 0; i < mirror::Class::kImtSize; ++i) { 4651 out_imt->SetReference(i, super_class->GetEmbeddedImTableEntry(i)); 4652 } 4653 } else { 4654 // No imt in the super class, need to reconstruct from the iftable. 4655 mirror::IfTable* if_table = super_class->GetIfTable(); 4656 mirror::ArtMethod* conflict_method = runtime->GetImtConflictMethod(); 4657 const size_t length = super_class->GetIfTableCount(); 4658 for (size_t i = 0; i < length; ++i) { 4659 mirror::Class* interface = iftable->GetInterface(i); 4660 const size_t num_virtuals = interface->NumVirtualMethods(); 4661 const size_t method_array_count = if_table->GetMethodArrayCount(i); 4662 DCHECK_EQ(num_virtuals, method_array_count); 4663 if (method_array_count == 0) { 4664 continue; 4665 } 4666 mirror::ObjectArray<mirror::ArtMethod>* method_array = if_table->GetMethodArray(i); 4667 for (size_t j = 0; j < num_virtuals; ++j) { 4668 mirror::ArtMethod* method = method_array->GetWithoutChecks(j); 4669 if (method->IsMiranda()) { 4670 continue; 4671 } 4672 mirror::ArtMethod* interface_method = interface->GetVirtualMethod(j); 4673 uint32_t imt_index = interface_method->GetDexMethodIndex() % mirror::Class::kImtSize; 4674 mirror::ArtMethod* imt_ref = out_imt->GetReference(imt_index)->AsArtMethod(); 4675 if (imt_ref == runtime->GetImtUnimplementedMethod()) { 4676 out_imt->SetReference(imt_index, method); 4677 } else if (imt_ref != conflict_method) { 4678 out_imt->SetReference(imt_index, conflict_method); 4679 } 4680 } 4681 } 4682 } 4683 } 4684 for (size_t i = 0; i < ifcount; ++i) { 4685 self->AllowThreadSuspension(); 4686 size_t num_methods = iftable->GetInterface(i)->NumVirtualMethods(); 4687 if (num_methods > 0) { 4688 StackHandleScope<2> hs2(self); 4689 const bool is_super = i < super_ifcount; 4690 const bool super_interface = is_super && extend_super_iftable; 4691 Handle<mirror::ObjectArray<mirror::ArtMethod>> method_array; 4692 Handle<mirror::ObjectArray<mirror::ArtMethod>> input_array; 4693 if (super_interface) { 4694 mirror::IfTable* if_table = klass->GetSuperClass()->GetIfTable(); 4695 DCHECK(if_table != nullptr); 4696 DCHECK(if_table->GetMethodArray(i) != nullptr); 4697 // If we are working on a super interface, try extending the existing method array. 4698 method_array = hs2.NewHandle(if_table->GetMethodArray(i)->Clone(self)-> 4699 AsObjectArray<mirror::ArtMethod>()); 4700 // We are overwriting a super class interface, try to only virtual methods instead of the 4701 // whole vtable. 4702 input_array = hs2.NewHandle(klass->GetVirtualMethods()); 4703 } else { 4704 method_array = hs2.NewHandle(AllocArtMethodArray(self, num_methods)); 4705 // A new interface, we need the whole vtable incase a new interface method is implemented 4706 // in the whole superclass. 4707 input_array = vtable; 4708 } 4709 if (UNLIKELY(method_array.Get() == nullptr)) { 4710 CHECK(self->IsExceptionPending()); // OOME. 4711 return false; 4712 } 4713 iftable->SetMethodArray(i, method_array.Get()); 4714 if (input_array.Get() == nullptr) { 4715 // If the added virtual methods is empty, do nothing. 4716 DCHECK(super_interface); 4717 continue; 4718 } 4719 for (size_t j = 0; j < num_methods; ++j) { 4720 mirror::ArtMethod* interface_method = iftable->GetInterface(i)->GetVirtualMethod(j); 4721 MethodNameAndSignatureComparator interface_name_comparator( 4722 interface_method->GetInterfaceMethodIfProxy()); 4723 int32_t k; 4724 // For each method listed in the interface's method list, find the 4725 // matching method in our class's method list. We want to favor the 4726 // subclass over the superclass, which just requires walking 4727 // back from the end of the vtable. (This only matters if the 4728 // superclass defines a private method and this class redefines 4729 // it -- otherwise it would use the same vtable slot. In .dex files 4730 // those don't end up in the virtual method table, so it shouldn't 4731 // matter which direction we go. We walk it backward anyway.) 4732 for (k = input_array->GetLength() - 1; k >= 0; --k) { 4733 mirror::ArtMethod* vtable_method = input_array->GetWithoutChecks(k); 4734 mirror::ArtMethod* vtable_method_for_name_comparison = 4735 vtable_method->GetInterfaceMethodIfProxy(); 4736 if (interface_name_comparator.HasSameNameAndSignature( 4737 vtable_method_for_name_comparison)) { 4738 if (!vtable_method->IsAbstract() && !vtable_method->IsPublic()) { 4739 ThrowIllegalAccessError( 4740 klass.Get(), 4741 "Method '%s' implementing interface method '%s' is not public", 4742 PrettyMethod(vtable_method).c_str(), 4743 PrettyMethod(interface_method).c_str()); 4744 return false; 4745 } 4746 method_array->SetWithoutChecks<false>(j, vtable_method); 4747 // Place method in imt if entry is empty, place conflict otherwise. 4748 uint32_t imt_index = interface_method->GetDexMethodIndex() % mirror::Class::kImtSize; 4749 mirror::ArtMethod* imt_ref = out_imt->GetReference(imt_index)->AsArtMethod(); 4750 mirror::ArtMethod* conflict_method = runtime->GetImtConflictMethod(); 4751 if (imt_ref == runtime->GetImtUnimplementedMethod()) { 4752 out_imt->SetReference(imt_index, vtable_method); 4753 } else if (imt_ref != conflict_method) { 4754 // If we are not a conflict and we have the same signature and name as the imt entry, 4755 // it must be that we overwrote a superclass vtable entry. 4756 MethodNameAndSignatureComparator imt_ref_name_comparator( 4757 imt_ref->GetInterfaceMethodIfProxy()); 4758 if (imt_ref_name_comparator.HasSameNameAndSignature( 4759 vtable_method_for_name_comparison)) { 4760 out_imt->SetReference(imt_index, vtable_method); 4761 } else { 4762 out_imt->SetReference(imt_index, conflict_method); 4763 } 4764 } 4765 break; 4766 } 4767 } 4768 if (k < 0 && !super_interface) { 4769 mirror::ArtMethod* miranda_method = nullptr; 4770 for (size_t l = 0; l < miranda_list_size; ++l) { 4771 mirror::ArtMethod* mir_method = miranda_list->Get(l); 4772 if (interface_name_comparator.HasSameNameAndSignature(mir_method)) { 4773 miranda_method = mir_method; 4774 break; 4775 } 4776 } 4777 if (miranda_method == nullptr) { 4778 // Point the interface table at a phantom slot. 4779 miranda_method = interface_method->Clone(self)->AsArtMethod(); 4780 if (UNLIKELY(miranda_method == nullptr)) { 4781 CHECK(self->IsExceptionPending()); // OOME. 4782 return false; 4783 } 4784 DCHECK_LT(miranda_list_size, max_miranda_methods); 4785 miranda_list->Set<false>(miranda_list_size++, miranda_method); 4786 } 4787 method_array->SetWithoutChecks<false>(j, miranda_method); 4788 } 4789 } 4790 } 4791 } 4792 if (miranda_list_size > 0) { 4793 int old_method_count = klass->NumVirtualMethods(); 4794 int new_method_count = old_method_count + miranda_list_size; 4795 mirror::ObjectArray<mirror::ArtMethod>* virtuals; 4796 if (old_method_count == 0) { 4797 virtuals = AllocArtMethodArray(self, new_method_count); 4798 } else { 4799 virtuals = klass->GetVirtualMethods()->CopyOf(self, new_method_count); 4800 } 4801 if (UNLIKELY(virtuals == nullptr)) { 4802 CHECK(self->IsExceptionPending()); // OOME. 4803 return false; 4804 } 4805 klass->SetVirtualMethods(virtuals); 4806 4807 int old_vtable_count = vtable->GetLength(); 4808 int new_vtable_count = old_vtable_count + miranda_list_size; 4809 vtable.Assign(vtable->CopyOf(self, new_vtable_count)); 4810 if (UNLIKELY(vtable.Get() == nullptr)) { 4811 CHECK(self->IsExceptionPending()); // OOME. 4812 return false; 4813 } 4814 for (size_t i = 0; i < miranda_list_size; ++i) { 4815 mirror::ArtMethod* method = miranda_list->Get(i); 4816 // Leave the declaring class alone as type indices are relative to it 4817 method->SetAccessFlags(method->GetAccessFlags() | kAccMiranda); 4818 method->SetMethodIndex(0xFFFF & (old_vtable_count + i)); 4819 klass->SetVirtualMethod(old_method_count + i, method); 4820 vtable->SetWithoutChecks<false>(old_vtable_count + i, method); 4821 } 4822 // TODO: do not assign to the vtable field until it is fully constructed. 4823 klass->SetVTable(vtable.Get()); 4824 } 4825 4826 if (kIsDebugBuild) { 4827 mirror::ObjectArray<mirror::ArtMethod>* check_vtable = klass->GetVTableDuringLinking(); 4828 for (int i = 0; i < check_vtable->GetLength(); ++i) { 4829 CHECK(check_vtable->GetWithoutChecks(i) != nullptr); 4830 } 4831 } 4832 4833 self->AllowThreadSuspension(); 4834 return true; 4835} 4836 4837bool ClassLinker::LinkInstanceFields(Thread* self, Handle<mirror::Class> klass) { 4838 CHECK(klass.Get() != nullptr); 4839 return LinkFields(self, klass, false, nullptr); 4840} 4841 4842bool ClassLinker::LinkStaticFields(Thread* self, Handle<mirror::Class> klass, size_t* class_size) { 4843 CHECK(klass.Get() != nullptr); 4844 return LinkFields(self, klass, true, class_size); 4845} 4846 4847struct LinkFieldsComparator { 4848 explicit LinkFieldsComparator() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 4849 } 4850 // No thread safety analysis as will be called from STL. Checked lock held in constructor. 4851 bool operator()(ArtField* field1, ArtField* field2) 4852 NO_THREAD_SAFETY_ANALYSIS { 4853 // First come reference fields, then 64-bit, then 32-bit, and then 16-bit, then finally 8-bit. 4854 Primitive::Type type1 = field1->GetTypeAsPrimitiveType(); 4855 Primitive::Type type2 = field2->GetTypeAsPrimitiveType(); 4856 if (type1 != type2) { 4857 if (type1 == Primitive::kPrimNot) { 4858 // Reference always goes first. 4859 return true; 4860 } 4861 if (type2 == Primitive::kPrimNot) { 4862 // Reference always goes first. 4863 return false; 4864 } 4865 size_t size1 = Primitive::ComponentSize(type1); 4866 size_t size2 = Primitive::ComponentSize(type2); 4867 if (size1 != size2) { 4868 // Larger primitive types go first. 4869 return size1 > size2; 4870 } 4871 // Primitive types differ but sizes match. Arbitrarily order by primitive type. 4872 return type1 < type2; 4873 } 4874 // Same basic group? Then sort by dex field index. This is guaranteed to be sorted 4875 // by name and for equal names by type id index. 4876 // NOTE: This works also for proxies. Their static fields are assigned appropriate indexes. 4877 return field1->GetDexFieldIndex() < field2->GetDexFieldIndex(); 4878 } 4879}; 4880 4881bool ClassLinker::LinkFields(Thread* self, Handle<mirror::Class> klass, bool is_static, 4882 size_t* class_size) { 4883 self->AllowThreadSuspension(); 4884 const size_t num_fields = is_static ? klass->NumStaticFields() : klass->NumInstanceFields(); 4885 ArtField* const fields = is_static ? klass->GetSFields() : klass->GetIFields(); 4886 4887 // Initialize field_offset 4888 MemberOffset field_offset(0); 4889 if (is_static) { 4890 field_offset = klass->GetFirstReferenceStaticFieldOffsetDuringLinking(); 4891 } else { 4892 mirror::Class* super_class = klass->GetSuperClass(); 4893 if (super_class != nullptr) { 4894 CHECK(super_class->IsResolved()) 4895 << PrettyClass(klass.Get()) << " " << PrettyClass(super_class); 4896 field_offset = MemberOffset(super_class->GetObjectSize()); 4897 } 4898 } 4899 4900 CHECK_EQ(num_fields == 0, fields == nullptr) << PrettyClass(klass.Get()); 4901 4902 // we want a relatively stable order so that adding new fields 4903 // minimizes disruption of C++ version such as Class and Method. 4904 std::deque<ArtField*> grouped_and_sorted_fields; 4905 const char* old_no_suspend_cause = self->StartAssertNoThreadSuspension( 4906 "Naked ArtField references in deque"); 4907 for (size_t i = 0; i < num_fields; i++) { 4908 grouped_and_sorted_fields.push_back(&fields[i]); 4909 } 4910 std::sort(grouped_and_sorted_fields.begin(), grouped_and_sorted_fields.end(), 4911 LinkFieldsComparator()); 4912 4913 // References should be at the front. 4914 size_t current_field = 0; 4915 size_t num_reference_fields = 0; 4916 FieldGaps gaps; 4917 4918 for (; current_field < num_fields; current_field++) { 4919 ArtField* field = grouped_and_sorted_fields.front(); 4920 Primitive::Type type = field->GetTypeAsPrimitiveType(); 4921 bool isPrimitive = type != Primitive::kPrimNot; 4922 if (isPrimitive) { 4923 break; // past last reference, move on to the next phase 4924 } 4925 if (UNLIKELY(!IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>( 4926 field_offset.Uint32Value()))) { 4927 MemberOffset old_offset = field_offset; 4928 field_offset = MemberOffset(RoundUp(field_offset.Uint32Value(), 4)); 4929 AddFieldGap(old_offset.Uint32Value(), field_offset.Uint32Value(), &gaps); 4930 } 4931 DCHECK(IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>(field_offset.Uint32Value())); 4932 grouped_and_sorted_fields.pop_front(); 4933 num_reference_fields++; 4934 field->SetOffset(field_offset); 4935 field_offset = MemberOffset(field_offset.Uint32Value() + 4936 sizeof(mirror::HeapReference<mirror::Object>)); 4937 } 4938 // Gaps are stored as a max heap which means that we must shuffle from largest to smallest 4939 // otherwise we could end up with suboptimal gap fills. 4940 ShuffleForward<8>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 4941 ShuffleForward<4>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 4942 ShuffleForward<2>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 4943 ShuffleForward<1>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 4944 CHECK(grouped_and_sorted_fields.empty()) << "Missed " << grouped_and_sorted_fields.size() << 4945 " fields."; 4946 self->EndAssertNoThreadSuspension(old_no_suspend_cause); 4947 4948 // We lie to the GC about the java.lang.ref.Reference.referent field, so it doesn't scan it. 4949 if (!is_static && klass->DescriptorEquals("Ljava/lang/ref/Reference;")) { 4950 // We know there are no non-reference fields in the Reference classes, and we know 4951 // that 'referent' is alphabetically last, so this is easy... 4952 CHECK_EQ(num_reference_fields, num_fields) << PrettyClass(klass.Get()); 4953 CHECK_STREQ(fields[num_fields - 1].GetName(), "referent") << PrettyClass(klass.Get()); 4954 --num_reference_fields; 4955 } 4956 4957 size_t size = field_offset.Uint32Value(); 4958 // Update klass 4959 if (is_static) { 4960 klass->SetNumReferenceStaticFields(num_reference_fields); 4961 *class_size = size; 4962 } else { 4963 klass->SetNumReferenceInstanceFields(num_reference_fields); 4964 if (!klass->IsVariableSize()) { 4965 if (klass->DescriptorEquals("Ljava/lang/reflect/ArtMethod;")) { 4966 size_t pointer_size = GetInstructionSetPointerSize(Runtime::Current()->GetInstructionSet()); 4967 klass->SetObjectSize(mirror::ArtMethod::InstanceSize(pointer_size)); 4968 } else { 4969 std::string temp; 4970 DCHECK_GE(size, sizeof(mirror::Object)) << klass->GetDescriptor(&temp); 4971 size_t previous_size = klass->GetObjectSize(); 4972 if (previous_size != 0) { 4973 // Make sure that we didn't originally have an incorrect size. 4974 CHECK_EQ(previous_size, size) << klass->GetDescriptor(&temp); 4975 } 4976 klass->SetObjectSize(size); 4977 } 4978 } 4979 } 4980 4981 if (kIsDebugBuild) { 4982 // Make sure that the fields array is ordered by name but all reference 4983 // offsets are at the beginning as far as alignment allows. 4984 MemberOffset start_ref_offset = is_static 4985 ? klass->GetFirstReferenceStaticFieldOffsetDuringLinking() 4986 : klass->GetFirstReferenceInstanceFieldOffset(); 4987 MemberOffset end_ref_offset(start_ref_offset.Uint32Value() + 4988 num_reference_fields * 4989 sizeof(mirror::HeapReference<mirror::Object>)); 4990 MemberOffset current_ref_offset = start_ref_offset; 4991 for (size_t i = 0; i < num_fields; i++) { 4992 ArtField* field = &fields[i]; 4993 VLOG(class_linker) << "LinkFields: " << (is_static ? "static" : "instance") 4994 << " class=" << PrettyClass(klass.Get()) << " field=" << PrettyField(field) << " offset=" 4995 << field->GetOffset(); 4996 if (i != 0) { 4997 ArtField* const prev_field = &fields[i - 1]; 4998 // NOTE: The field names can be the same. This is not possible in the Java language 4999 // but it's valid Java/dex bytecode and for example proguard can generate such bytecode. 5000 CHECK_LE(strcmp(prev_field->GetName(), field->GetName()), 0); 5001 } 5002 Primitive::Type type = field->GetTypeAsPrimitiveType(); 5003 bool is_primitive = type != Primitive::kPrimNot; 5004 if (klass->DescriptorEquals("Ljava/lang/ref/Reference;") && 5005 strcmp("referent", field->GetName()) == 0) { 5006 is_primitive = true; // We lied above, so we have to expect a lie here. 5007 } 5008 MemberOffset offset = field->GetOffsetDuringLinking(); 5009 if (is_primitive) { 5010 if (offset.Uint32Value() < end_ref_offset.Uint32Value()) { 5011 // Shuffled before references. 5012 size_t type_size = Primitive::ComponentSize(type); 5013 CHECK_LT(type_size, sizeof(mirror::HeapReference<mirror::Object>)); 5014 CHECK_LT(offset.Uint32Value(), start_ref_offset.Uint32Value()); 5015 CHECK_LE(offset.Uint32Value() + type_size, start_ref_offset.Uint32Value()); 5016 CHECK(!IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>(offset.Uint32Value())); 5017 } 5018 } else { 5019 CHECK_EQ(current_ref_offset.Uint32Value(), offset.Uint32Value()); 5020 current_ref_offset = MemberOffset(current_ref_offset.Uint32Value() + 5021 sizeof(mirror::HeapReference<mirror::Object>)); 5022 } 5023 } 5024 CHECK_EQ(current_ref_offset.Uint32Value(), end_ref_offset.Uint32Value()); 5025 } 5026 return true; 5027} 5028 5029// Set the bitmap of reference instance field offsets. 5030void ClassLinker::CreateReferenceInstanceOffsets(Handle<mirror::Class> klass) { 5031 uint32_t reference_offsets = 0; 5032 mirror::Class* super_class = klass->GetSuperClass(); 5033 // Leave the reference offsets as 0 for mirror::Object (the class field is handled specially). 5034 if (super_class != nullptr) { 5035 reference_offsets = super_class->GetReferenceInstanceOffsets(); 5036 // Compute reference offsets unless our superclass overflowed. 5037 if (reference_offsets != mirror::Class::kClassWalkSuper) { 5038 size_t num_reference_fields = klass->NumReferenceInstanceFieldsDuringLinking(); 5039 if (num_reference_fields != 0u) { 5040 // All of the fields that contain object references are guaranteed be grouped in memory 5041 // starting at an appropriately aligned address after super class object data. 5042 uint32_t start_offset = RoundUp(super_class->GetObjectSize(), 5043 sizeof(mirror::HeapReference<mirror::Object>)); 5044 uint32_t start_bit = (start_offset - mirror::kObjectHeaderSize) / 5045 sizeof(mirror::HeapReference<mirror::Object>); 5046 if (start_bit + num_reference_fields > 32) { 5047 reference_offsets = mirror::Class::kClassWalkSuper; 5048 } else { 5049 reference_offsets |= (0xffffffffu << start_bit) & 5050 (0xffffffffu >> (32 - (start_bit + num_reference_fields))); 5051 } 5052 } 5053 } 5054 } 5055 klass->SetReferenceInstanceOffsets(reference_offsets); 5056} 5057 5058mirror::String* ClassLinker::ResolveString(const DexFile& dex_file, uint32_t string_idx, 5059 Handle<mirror::DexCache> dex_cache) { 5060 DCHECK(dex_cache.Get() != nullptr); 5061 mirror::String* resolved = dex_cache->GetResolvedString(string_idx); 5062 if (resolved != nullptr) { 5063 return resolved; 5064 } 5065 uint32_t utf16_length; 5066 const char* utf8_data = dex_file.StringDataAndUtf16LengthByIdx(string_idx, &utf16_length); 5067 mirror::String* string = intern_table_->InternStrong(utf16_length, utf8_data); 5068 dex_cache->SetResolvedString(string_idx, string); 5069 return string; 5070} 5071 5072mirror::Class* ClassLinker::ResolveType(const DexFile& dex_file, uint16_t type_idx, 5073 mirror::Class* referrer) { 5074 StackHandleScope<2> hs(Thread::Current()); 5075 Handle<mirror::DexCache> dex_cache(hs.NewHandle(referrer->GetDexCache())); 5076 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(referrer->GetClassLoader())); 5077 return ResolveType(dex_file, type_idx, dex_cache, class_loader); 5078} 5079 5080mirror::Class* ClassLinker::ResolveType(const DexFile& dex_file, uint16_t type_idx, 5081 Handle<mirror::DexCache> dex_cache, 5082 Handle<mirror::ClassLoader> class_loader) { 5083 DCHECK(dex_cache.Get() != nullptr); 5084 mirror::Class* resolved = dex_cache->GetResolvedType(type_idx); 5085 if (resolved == nullptr) { 5086 Thread* self = Thread::Current(); 5087 const char* descriptor = dex_file.StringByTypeIdx(type_idx); 5088 resolved = FindClass(self, descriptor, class_loader); 5089 if (resolved != nullptr) { 5090 // TODO: we used to throw here if resolved's class loader was not the 5091 // boot class loader. This was to permit different classes with the 5092 // same name to be loaded simultaneously by different loaders 5093 dex_cache->SetResolvedType(type_idx, resolved); 5094 } else { 5095 CHECK(self->IsExceptionPending()) 5096 << "Expected pending exception for failed resolution of: " << descriptor; 5097 // Convert a ClassNotFoundException to a NoClassDefFoundError. 5098 StackHandleScope<1> hs(self); 5099 Handle<mirror::Throwable> cause(hs.NewHandle(self->GetException())); 5100 if (cause->InstanceOf(GetClassRoot(kJavaLangClassNotFoundException))) { 5101 DCHECK(resolved == nullptr); // No Handle needed to preserve resolved. 5102 self->ClearException(); 5103 ThrowNoClassDefFoundError("Failed resolution of: %s", descriptor); 5104 self->GetException()->SetCause(cause.Get()); 5105 } 5106 } 5107 } 5108 DCHECK((resolved == nullptr) || resolved->IsResolved() || resolved->IsErroneous()) 5109 << PrettyDescriptor(resolved) << " " << resolved->GetStatus(); 5110 return resolved; 5111} 5112 5113mirror::ArtMethod* ClassLinker::ResolveMethod(const DexFile& dex_file, uint32_t method_idx, 5114 Handle<mirror::DexCache> dex_cache, 5115 Handle<mirror::ClassLoader> class_loader, 5116 Handle<mirror::ArtMethod> referrer, 5117 InvokeType type) { 5118 DCHECK(dex_cache.Get() != nullptr); 5119 // Check for hit in the dex cache. 5120 mirror::ArtMethod* resolved = dex_cache->GetResolvedMethod(method_idx); 5121 if (resolved != nullptr && !resolved->IsRuntimeMethod()) { 5122 return resolved; 5123 } 5124 // Fail, get the declaring class. 5125 const DexFile::MethodId& method_id = dex_file.GetMethodId(method_idx); 5126 mirror::Class* klass = ResolveType(dex_file, method_id.class_idx_, dex_cache, class_loader); 5127 if (klass == nullptr) { 5128 DCHECK(Thread::Current()->IsExceptionPending()); 5129 return nullptr; 5130 } 5131 // Scan using method_idx, this saves string compares but will only hit for matching dex 5132 // caches/files. 5133 switch (type) { 5134 case kDirect: // Fall-through. 5135 case kStatic: 5136 resolved = klass->FindDirectMethod(dex_cache.Get(), method_idx); 5137 break; 5138 case kInterface: 5139 resolved = klass->FindInterfaceMethod(dex_cache.Get(), method_idx); 5140 DCHECK(resolved == nullptr || resolved->GetDeclaringClass()->IsInterface()); 5141 break; 5142 case kSuper: // Fall-through. 5143 case kVirtual: 5144 resolved = klass->FindVirtualMethod(dex_cache.Get(), method_idx); 5145 break; 5146 default: 5147 LOG(FATAL) << "Unreachable - invocation type: " << type; 5148 UNREACHABLE(); 5149 } 5150 if (resolved == nullptr) { 5151 // Search by name, which works across dex files. 5152 const char* name = dex_file.StringDataByIdx(method_id.name_idx_); 5153 const Signature signature = dex_file.GetMethodSignature(method_id); 5154 switch (type) { 5155 case kDirect: // Fall-through. 5156 case kStatic: 5157 resolved = klass->FindDirectMethod(name, signature); 5158 break; 5159 case kInterface: 5160 resolved = klass->FindInterfaceMethod(name, signature); 5161 DCHECK(resolved == nullptr || resolved->GetDeclaringClass()->IsInterface()); 5162 break; 5163 case kSuper: // Fall-through. 5164 case kVirtual: 5165 resolved = klass->FindVirtualMethod(name, signature); 5166 break; 5167 } 5168 } 5169 // If we found a method, check for incompatible class changes. 5170 if (LIKELY(resolved != nullptr && !resolved->CheckIncompatibleClassChange(type))) { 5171 // Be a good citizen and update the dex cache to speed subsequent calls. 5172 dex_cache->SetResolvedMethod(method_idx, resolved); 5173 return resolved; 5174 } else { 5175 // If we had a method, it's an incompatible-class-change error. 5176 if (resolved != nullptr) { 5177 ThrowIncompatibleClassChangeError(type, resolved->GetInvokeType(), resolved, referrer.Get()); 5178 } else { 5179 // We failed to find the method which means either an access error, an incompatible class 5180 // change, or no such method. First try to find the method among direct and virtual methods. 5181 const char* name = dex_file.StringDataByIdx(method_id.name_idx_); 5182 const Signature signature = dex_file.GetMethodSignature(method_id); 5183 switch (type) { 5184 case kDirect: 5185 case kStatic: 5186 resolved = klass->FindVirtualMethod(name, signature); 5187 // Note: kDirect and kStatic are also mutually exclusive, but in that case we would 5188 // have had a resolved method before, which triggers the "true" branch above. 5189 break; 5190 case kInterface: 5191 case kVirtual: 5192 case kSuper: 5193 resolved = klass->FindDirectMethod(name, signature); 5194 break; 5195 } 5196 5197 // If we found something, check that it can be accessed by the referrer. 5198 bool exception_generated = false; 5199 if (resolved != nullptr && referrer.Get() != nullptr) { 5200 mirror::Class* methods_class = resolved->GetDeclaringClass(); 5201 mirror::Class* referring_class = referrer->GetDeclaringClass(); 5202 if (!referring_class->CanAccess(methods_class)) { 5203 ThrowIllegalAccessErrorClassForMethodDispatch(referring_class, methods_class, 5204 resolved, type); 5205 exception_generated = true; 5206 } else if (!referring_class->CanAccessMember(methods_class, 5207 resolved->GetAccessFlags())) { 5208 ThrowIllegalAccessErrorMethod(referring_class, resolved); 5209 exception_generated = true; 5210 } 5211 } 5212 if (!exception_generated) { 5213 // Otherwise, throw an IncompatibleClassChangeError if we found something, and check 5214 // interface methods and throw if we find the method there. If we find nothing, throw a 5215 // NoSuchMethodError. 5216 switch (type) { 5217 case kDirect: 5218 case kStatic: 5219 if (resolved != nullptr) { 5220 ThrowIncompatibleClassChangeError(type, kVirtual, resolved, referrer.Get()); 5221 } else { 5222 resolved = klass->FindInterfaceMethod(name, signature); 5223 if (resolved != nullptr) { 5224 ThrowIncompatibleClassChangeError(type, kInterface, resolved, referrer.Get()); 5225 } else { 5226 ThrowNoSuchMethodError(type, klass, name, signature); 5227 } 5228 } 5229 break; 5230 case kInterface: 5231 if (resolved != nullptr) { 5232 ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer.Get()); 5233 } else { 5234 resolved = klass->FindVirtualMethod(name, signature); 5235 if (resolved != nullptr) { 5236 ThrowIncompatibleClassChangeError(type, kVirtual, resolved, referrer.Get()); 5237 } else { 5238 ThrowNoSuchMethodError(type, klass, name, signature); 5239 } 5240 } 5241 break; 5242 case kSuper: 5243 if (resolved != nullptr) { 5244 ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer.Get()); 5245 } else { 5246 ThrowNoSuchMethodError(type, klass, name, signature); 5247 } 5248 break; 5249 case kVirtual: 5250 if (resolved != nullptr) { 5251 ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer.Get()); 5252 } else { 5253 resolved = klass->FindInterfaceMethod(name, signature); 5254 if (resolved != nullptr) { 5255 ThrowIncompatibleClassChangeError(type, kInterface, resolved, referrer.Get()); 5256 } else { 5257 ThrowNoSuchMethodError(type, klass, name, signature); 5258 } 5259 } 5260 break; 5261 } 5262 } 5263 } 5264 Thread::Current()->AssertPendingException(); 5265 return nullptr; 5266 } 5267} 5268 5269ArtField* ClassLinker::ResolveField(const DexFile& dex_file, uint32_t field_idx, 5270 Handle<mirror::DexCache> dex_cache, 5271 Handle<mirror::ClassLoader> class_loader, bool is_static) { 5272 DCHECK(dex_cache.Get() != nullptr); 5273 ArtField* resolved = dex_cache->GetResolvedField(field_idx, image_pointer_size_); 5274 if (resolved != nullptr) { 5275 return resolved; 5276 } 5277 const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx); 5278 Thread* const self = Thread::Current(); 5279 StackHandleScope<1> hs(self); 5280 Handle<mirror::Class> klass( 5281 hs.NewHandle(ResolveType(dex_file, field_id.class_idx_, dex_cache, class_loader))); 5282 if (klass.Get() == nullptr) { 5283 DCHECK(Thread::Current()->IsExceptionPending()); 5284 return nullptr; 5285 } 5286 5287 if (is_static) { 5288 resolved = mirror::Class::FindStaticField(self, klass, dex_cache.Get(), field_idx); 5289 } else { 5290 resolved = klass->FindInstanceField(dex_cache.Get(), field_idx); 5291 } 5292 5293 if (resolved == nullptr) { 5294 const char* name = dex_file.GetFieldName(field_id); 5295 const char* type = dex_file.GetFieldTypeDescriptor(field_id); 5296 if (is_static) { 5297 resolved = mirror::Class::FindStaticField(self, klass, name, type); 5298 } else { 5299 resolved = klass->FindInstanceField(name, type); 5300 } 5301 if (resolved == nullptr) { 5302 ThrowNoSuchFieldError(is_static ? "static " : "instance ", klass.Get(), type, name); 5303 return nullptr; 5304 } 5305 } 5306 dex_cache->SetResolvedField(field_idx, resolved, image_pointer_size_); 5307 return resolved; 5308} 5309 5310ArtField* ClassLinker::ResolveFieldJLS(const DexFile& dex_file, uint32_t field_idx, 5311 Handle<mirror::DexCache> dex_cache, 5312 Handle<mirror::ClassLoader> class_loader) { 5313 DCHECK(dex_cache.Get() != nullptr); 5314 ArtField* resolved = dex_cache->GetResolvedField(field_idx, image_pointer_size_); 5315 if (resolved != nullptr) { 5316 return resolved; 5317 } 5318 const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx); 5319 Thread* self = Thread::Current(); 5320 StackHandleScope<1> hs(self); 5321 Handle<mirror::Class> klass( 5322 hs.NewHandle(ResolveType(dex_file, field_id.class_idx_, dex_cache, class_loader))); 5323 if (klass.Get() == nullptr) { 5324 DCHECK(Thread::Current()->IsExceptionPending()); 5325 return nullptr; 5326 } 5327 5328 StringPiece name(dex_file.StringDataByIdx(field_id.name_idx_)); 5329 StringPiece type(dex_file.StringDataByIdx( 5330 dex_file.GetTypeId(field_id.type_idx_).descriptor_idx_)); 5331 resolved = mirror::Class::FindField(self, klass, name, type); 5332 if (resolved != nullptr) { 5333 dex_cache->SetResolvedField(field_idx, resolved, image_pointer_size_); 5334 } else { 5335 ThrowNoSuchFieldError("", klass.Get(), type, name); 5336 } 5337 return resolved; 5338} 5339 5340const char* ClassLinker::MethodShorty(uint32_t method_idx, mirror::ArtMethod* referrer, 5341 uint32_t* length) { 5342 mirror::Class* declaring_class = referrer->GetDeclaringClass(); 5343 mirror::DexCache* dex_cache = declaring_class->GetDexCache(); 5344 const DexFile& dex_file = *dex_cache->GetDexFile(); 5345 const DexFile::MethodId& method_id = dex_file.GetMethodId(method_idx); 5346 return dex_file.GetMethodShorty(method_id, length); 5347} 5348 5349void ClassLinker::DumpAllClasses(int flags) { 5350 if (dex_cache_image_class_lookup_required_) { 5351 MoveImageClassesToClassTable(); 5352 } 5353 // TODO: at the time this was written, it wasn't safe to call PrettyField with the ClassLinker 5354 // lock held, because it might need to resolve a field's type, which would try to take the lock. 5355 std::vector<mirror::Class*> all_classes; 5356 { 5357 ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 5358 for (GcRoot<mirror::Class>& it : class_table_) { 5359 all_classes.push_back(it.Read()); 5360 } 5361 } 5362 5363 for (size_t i = 0; i < all_classes.size(); ++i) { 5364 all_classes[i]->DumpClass(std::cerr, flags); 5365 } 5366} 5367 5368static OatFile::OatMethod CreateOatMethod(const void* code) { 5369 CHECK(code != nullptr); 5370 const uint8_t* base = reinterpret_cast<const uint8_t*>(code); // Base of data points at code. 5371 base -= sizeof(void*); // Move backward so that code_offset != 0. 5372 const uint32_t code_offset = sizeof(void*); 5373 return OatFile::OatMethod(base, code_offset); 5374} 5375 5376bool ClassLinker::IsQuickResolutionStub(const void* entry_point) const { 5377 return (entry_point == GetQuickResolutionStub()) || 5378 (quick_resolution_trampoline_ == entry_point); 5379} 5380 5381bool ClassLinker::IsQuickToInterpreterBridge(const void* entry_point) const { 5382 return (entry_point == GetQuickToInterpreterBridge()) || 5383 (quick_to_interpreter_bridge_trampoline_ == entry_point); 5384} 5385 5386bool ClassLinker::IsQuickGenericJniStub(const void* entry_point) const { 5387 return (entry_point == GetQuickGenericJniStub()) || 5388 (quick_generic_jni_trampoline_ == entry_point); 5389} 5390 5391const void* ClassLinker::GetRuntimeQuickGenericJniStub() const { 5392 return GetQuickGenericJniStub(); 5393} 5394 5395void ClassLinker::SetEntryPointsToCompiledCode(mirror::ArtMethod* method, 5396 const void* method_code) const { 5397 OatFile::OatMethod oat_method = CreateOatMethod(method_code); 5398 oat_method.LinkMethod(method); 5399 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 5400} 5401 5402void ClassLinker::SetEntryPointsToInterpreter(mirror::ArtMethod* method) const { 5403 if (!method->IsNative()) { 5404 method->SetEntryPointFromInterpreter(artInterpreterToInterpreterBridge); 5405 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge()); 5406 } else { 5407 const void* quick_method_code = GetQuickGenericJniStub(); 5408 OatFile::OatMethod oat_method = CreateOatMethod(quick_method_code); 5409 oat_method.LinkMethod(method); 5410 method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge); 5411 } 5412} 5413 5414void ClassLinker::DumpForSigQuit(std::ostream& os) { 5415 Thread* self = Thread::Current(); 5416 if (dex_cache_image_class_lookup_required_) { 5417 ScopedObjectAccess soa(self); 5418 MoveImageClassesToClassTable(); 5419 } 5420 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 5421 os << "Zygote loaded classes=" << pre_zygote_class_table_.Size() << " post zygote classes=" 5422 << class_table_.Size() << "\n"; 5423} 5424 5425size_t ClassLinker::NumLoadedClasses() { 5426 if (dex_cache_image_class_lookup_required_) { 5427 MoveImageClassesToClassTable(); 5428 } 5429 ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 5430 // Only return non zygote classes since these are the ones which apps which care about. 5431 return class_table_.Size(); 5432} 5433 5434pid_t ClassLinker::GetClassesLockOwner() { 5435 return Locks::classlinker_classes_lock_->GetExclusiveOwnerTid(); 5436} 5437 5438pid_t ClassLinker::GetDexLockOwner() { 5439 return dex_lock_.GetExclusiveOwnerTid(); 5440} 5441 5442void ClassLinker::SetClassRoot(ClassRoot class_root, mirror::Class* klass) { 5443 DCHECK(!init_done_); 5444 5445 DCHECK(klass != nullptr); 5446 DCHECK(klass->GetClassLoader() == nullptr); 5447 5448 mirror::ObjectArray<mirror::Class>* class_roots = class_roots_.Read(); 5449 DCHECK(class_roots != nullptr); 5450 DCHECK(class_roots->Get(class_root) == nullptr); 5451 class_roots->Set<false>(class_root, klass); 5452} 5453 5454const char* ClassLinker::GetClassRootDescriptor(ClassRoot class_root) { 5455 static const char* class_roots_descriptors[] = { 5456 "Ljava/lang/Class;", 5457 "Ljava/lang/Object;", 5458 "[Ljava/lang/Class;", 5459 "[Ljava/lang/Object;", 5460 "Ljava/lang/String;", 5461 "Ljava/lang/DexCache;", 5462 "Ljava/lang/ref/Reference;", 5463 "Ljava/lang/reflect/ArtMethod;", 5464 "Ljava/lang/reflect/Constructor;", 5465 "Ljava/lang/reflect/Field;", 5466 "Ljava/lang/reflect/Method;", 5467 "Ljava/lang/reflect/Proxy;", 5468 "[Ljava/lang/String;", 5469 "[Ljava/lang/reflect/ArtMethod;", 5470 "[Ljava/lang/reflect/Constructor;", 5471 "[Ljava/lang/reflect/Field;", 5472 "[Ljava/lang/reflect/Method;", 5473 "Ljava/lang/ClassLoader;", 5474 "Ljava/lang/Throwable;", 5475 "Ljava/lang/ClassNotFoundException;", 5476 "Ljava/lang/StackTraceElement;", 5477 "Z", 5478 "B", 5479 "C", 5480 "D", 5481 "F", 5482 "I", 5483 "J", 5484 "S", 5485 "V", 5486 "[Z", 5487 "[B", 5488 "[C", 5489 "[D", 5490 "[F", 5491 "[I", 5492 "[J", 5493 "[S", 5494 "[Ljava/lang/StackTraceElement;", 5495 }; 5496 static_assert(arraysize(class_roots_descriptors) == size_t(kClassRootsMax), 5497 "Mismatch between class descriptors and class-root enum"); 5498 5499 const char* descriptor = class_roots_descriptors[class_root]; 5500 CHECK(descriptor != nullptr); 5501 return descriptor; 5502} 5503 5504std::size_t ClassLinker::ClassDescriptorHashEquals::operator()(const GcRoot<mirror::Class>& root) 5505 const { 5506 std::string temp; 5507 return ComputeModifiedUtf8Hash(root.Read()->GetDescriptor(&temp)); 5508} 5509 5510bool ClassLinker::ClassDescriptorHashEquals::operator()(const GcRoot<mirror::Class>& a, 5511 const GcRoot<mirror::Class>& b) const { 5512 if (a.Read()->GetClassLoader() != b.Read()->GetClassLoader()) { 5513 return false; 5514 } 5515 std::string temp; 5516 return a.Read()->DescriptorEquals(b.Read()->GetDescriptor(&temp)); 5517} 5518 5519std::size_t ClassLinker::ClassDescriptorHashEquals::operator()( 5520 const std::pair<const char*, mirror::ClassLoader*>& element) const { 5521 return ComputeModifiedUtf8Hash(element.first); 5522} 5523 5524bool ClassLinker::ClassDescriptorHashEquals::operator()( 5525 const GcRoot<mirror::Class>& a, const std::pair<const char*, mirror::ClassLoader*>& b) const { 5526 if (a.Read()->GetClassLoader() != b.second) { 5527 return false; 5528 } 5529 return a.Read()->DescriptorEquals(b.first); 5530} 5531 5532bool ClassLinker::ClassDescriptorHashEquals::operator()(const GcRoot<mirror::Class>& a, 5533 const char* descriptor) const { 5534 return a.Read()->DescriptorEquals(descriptor); 5535} 5536 5537std::size_t ClassLinker::ClassDescriptorHashEquals::operator()(const char* descriptor) const { 5538 return ComputeModifiedUtf8Hash(descriptor); 5539} 5540 5541bool ClassLinker::MayBeCalledWithDirectCodePointer(mirror::ArtMethod* m) { 5542 if (Runtime::Current()->UseJit()) { 5543 // JIT can have direct code pointers from any method to any other method. 5544 return true; 5545 } 5546 // Non-image methods don't use direct code pointer. 5547 if (!m->GetDeclaringClass()->IsBootStrapClassLoaded()) { 5548 return false; 5549 } 5550 if (m->IsPrivate()) { 5551 // The method can only be called inside its own oat file. Therefore it won't be called using 5552 // its direct code if the oat file has been compiled in PIC mode. 5553 const DexFile& dex_file = m->GetDeclaringClass()->GetDexFile(); 5554 const OatFile::OatDexFile* oat_dex_file = dex_file.GetOatDexFile(); 5555 if (oat_dex_file == nullptr) { 5556 // No oat file: the method has not been compiled. 5557 return false; 5558 } 5559 const OatFile* oat_file = oat_dex_file->GetOatFile(); 5560 return oat_file != nullptr && !oat_file->IsPic(); 5561 } else { 5562 // The method can be called outside its own oat file. Therefore it won't be called using its 5563 // direct code pointer only if all loaded oat files have been compiled in PIC mode. 5564 ReaderMutexLock mu(Thread::Current(), dex_lock_); 5565 for (const OatFile* oat_file : oat_files_) { 5566 if (!oat_file->IsPic()) { 5567 return true; 5568 } 5569 } 5570 return false; 5571 } 5572} 5573 5574jobject ClassLinker::CreatePathClassLoader(Thread* self, std::vector<const DexFile*>& dex_files) { 5575 // SOAAlreadyRunnable is protected, and we need something to add a global reference. 5576 // We could move the jobject to the callers, but all call-sites do this... 5577 ScopedObjectAccessUnchecked soa(self); 5578 5579 // Register the dex files. 5580 for (const DexFile* dex_file : dex_files) { 5581 RegisterDexFile(*dex_file); 5582 } 5583 5584 // For now, create a libcore-level DexFile for each ART DexFile. This "explodes" multidex. 5585 StackHandleScope<10> hs(self); 5586 5587 ArtField* dex_elements_field = 5588 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList_dexElements); 5589 5590 mirror::Class* dex_elements_class = dex_elements_field->GetType<true>(); 5591 DCHECK(dex_elements_class != nullptr); 5592 DCHECK(dex_elements_class->IsArrayClass()); 5593 Handle<mirror::ObjectArray<mirror::Object>> h_dex_elements(hs.NewHandle( 5594 mirror::ObjectArray<mirror::Object>::Alloc(self, dex_elements_class, dex_files.size()))); 5595 Handle<mirror::Class> h_dex_element_class = 5596 hs.NewHandle(dex_elements_class->GetComponentType()); 5597 5598 ArtField* element_file_field = 5599 soa.DecodeField(WellKnownClasses::dalvik_system_DexPathList__Element_dexFile); 5600 DCHECK_EQ(h_dex_element_class.Get(), element_file_field->GetDeclaringClass()); 5601 5602 ArtField* cookie_field = soa.DecodeField(WellKnownClasses::dalvik_system_DexFile_cookie); 5603 DCHECK_EQ(cookie_field->GetDeclaringClass(), element_file_field->GetType<false>()); 5604 5605 // Fill the elements array. 5606 int32_t index = 0; 5607 for (const DexFile* dex_file : dex_files) { 5608 StackHandleScope<3> hs2(self); 5609 5610 Handle<mirror::LongArray> h_long_array = hs2.NewHandle(mirror::LongArray::Alloc(self, 1)); 5611 DCHECK(h_long_array.Get() != nullptr); 5612 h_long_array->Set(0, reinterpret_cast<intptr_t>(dex_file)); 5613 5614 Handle<mirror::Object> h_dex_file = hs2.NewHandle( 5615 cookie_field->GetDeclaringClass()->AllocObject(self)); 5616 DCHECK(h_dex_file.Get() != nullptr); 5617 cookie_field->SetObject<false>(h_dex_file.Get(), h_long_array.Get()); 5618 5619 Handle<mirror::Object> h_element = hs2.NewHandle(h_dex_element_class->AllocObject(self)); 5620 DCHECK(h_element.Get() != nullptr); 5621 element_file_field->SetObject<false>(h_element.Get(), h_dex_file.Get()); 5622 5623 h_dex_elements->Set(index, h_element.Get()); 5624 index++; 5625 } 5626 DCHECK_EQ(index, h_dex_elements->GetLength()); 5627 5628 // Create DexPathList. 5629 Handle<mirror::Object> h_dex_path_list = hs.NewHandle( 5630 dex_elements_field->GetDeclaringClass()->AllocObject(self)); 5631 DCHECK(h_dex_path_list.Get() != nullptr); 5632 // Set elements. 5633 dex_elements_field->SetObject<false>(h_dex_path_list.Get(), h_dex_elements.Get()); 5634 5635 // Create PathClassLoader. 5636 Handle<mirror::Class> h_path_class_class = hs.NewHandle( 5637 soa.Decode<mirror::Class*>(WellKnownClasses::dalvik_system_PathClassLoader)); 5638 Handle<mirror::Object> h_path_class_loader = hs.NewHandle( 5639 h_path_class_class->AllocObject(self)); 5640 DCHECK(h_path_class_loader.Get() != nullptr); 5641 // Set DexPathList. 5642 ArtField* path_list_field = 5643 soa.DecodeField(WellKnownClasses::dalvik_system_PathClassLoader_pathList); 5644 DCHECK(path_list_field != nullptr); 5645 path_list_field->SetObject<false>(h_path_class_loader.Get(), h_dex_path_list.Get()); 5646 5647 // Make a pretend boot-classpath. 5648 // TODO: Should we scan the image? 5649 ArtField* const parent_field = 5650 mirror::Class::FindField(self, hs.NewHandle(h_path_class_loader->GetClass()), "parent", 5651 "Ljava/lang/ClassLoader;"); 5652 DCHECK(parent_field!= nullptr); 5653 mirror::Object* boot_cl = 5654 soa.Decode<mirror::Class*>(WellKnownClasses::java_lang_BootClassLoader)->AllocObject(self); 5655 parent_field->SetObject<false>(h_path_class_loader.Get(), boot_cl); 5656 5657 // Make it a global ref and return. 5658 ScopedLocalRef<jobject> local_ref( 5659 soa.Env(), soa.Env()->AddLocalReference<jobject>(h_path_class_loader.Get())); 5660 return soa.Env()->NewGlobalRef(local_ref.get()); 5661} 5662 5663} // namespace art 5664