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 <algorithm> 20 #include <deque> 21 #include <iostream> 22 #include <map> 23 #include <memory> 24 #include <queue> 25 #include <string> 26 #include <tuple> 27 #include <unistd.h> 28 #include <unordered_map> 29 #include <utility> 30 #include <vector> 31 32 #include "android-base/stringprintf.h" 33 34 #include "art_field-inl.h" 35 #include "art_method-inl.h" 36 #include "base/arena_allocator.h" 37 #include "base/casts.h" 38 #include "base/logging.h" 39 #include "base/scoped_arena_containers.h" 40 #include "base/scoped_flock.h" 41 #include "base/stl_util.h" 42 #include "base/systrace.h" 43 #include "base/time_utils.h" 44 #include "base/unix_file/fd_file.h" 45 #include "base/value_object.h" 46 #include "cha.h" 47 #include "class_linker-inl.h" 48 #include "class_loader_utils.h" 49 #include "class_table-inl.h" 50 #include "compiler_callbacks.h" 51 #include "debugger.h" 52 #include "dex_file-inl.h" 53 #include "entrypoints/entrypoint_utils.h" 54 #include "entrypoints/runtime_asm_entrypoints.h" 55 #include "experimental_flags.h" 56 #include "gc/accounting/card_table-inl.h" 57 #include "gc/accounting/heap_bitmap-inl.h" 58 #include "gc/accounting/space_bitmap-inl.h" 59 #include "gc/heap-visit-objects-inl.h" 60 #include "gc/heap.h" 61 #include "gc/scoped_gc_critical_section.h" 62 #include "gc/space/image_space.h" 63 #include "gc/space/space-inl.h" 64 #include "gc_root-inl.h" 65 #include "handle_scope-inl.h" 66 #include "image-inl.h" 67 #include "imt_conflict_table.h" 68 #include "imtable-inl.h" 69 #include "intern_table.h" 70 #include "interpreter/interpreter.h" 71 #include "java_vm_ext.h" 72 #include "jit/jit.h" 73 #include "jit/jit_code_cache.h" 74 #include "jit/profile_compilation_info.h" 75 #include "jni_internal.h" 76 #include "leb128.h" 77 #include "linear_alloc.h" 78 #include "mirror/call_site.h" 79 #include "mirror/class-inl.h" 80 #include "mirror/class.h" 81 #include "mirror/class_ext.h" 82 #include "mirror/class_loader.h" 83 #include "mirror/dex_cache-inl.h" 84 #include "mirror/dex_cache.h" 85 #include "mirror/emulated_stack_frame.h" 86 #include "mirror/field.h" 87 #include "mirror/iftable-inl.h" 88 #include "mirror/method.h" 89 #include "mirror/method_handle_impl.h" 90 #include "mirror/method_handles_lookup.h" 91 #include "mirror/method_type.h" 92 #include "mirror/object-inl.h" 93 #include "mirror/object-refvisitor-inl.h" 94 #include "mirror/object_array-inl.h" 95 #include "mirror/proxy.h" 96 #include "mirror/reference-inl.h" 97 #include "mirror/stack_trace_element.h" 98 #include "mirror/string-inl.h" 99 #include "native/dalvik_system_DexFile.h" 100 #include "nativehelper/ScopedLocalRef.h" 101 #include "oat.h" 102 #include "oat_file-inl.h" 103 #include "oat_file.h" 104 #include "oat_file_assistant.h" 105 #include "oat_file_manager.h" 106 #include "object_lock.h" 107 #include "os.h" 108 #include "runtime.h" 109 #include "runtime_callbacks.h" 110 #include "scoped_thread_state_change-inl.h" 111 #include "thread-inl.h" 112 #include "thread_list.h" 113 #include "trace.h" 114 #include "utf.h" 115 #include "utils.h" 116 #include "utils/dex_cache_arrays_layout-inl.h" 117 #include "verifier/method_verifier.h" 118 #include "well_known_classes.h" 119 120 namespace art { 121 122 using android::base::StringPrintf; 123 124 static constexpr bool kSanityCheckObjects = kIsDebugBuild; 125 static constexpr bool kVerifyArtMethodDeclaringClasses = kIsDebugBuild; 126 127 static void ThrowNoClassDefFoundError(const char* fmt, ...) 128 __attribute__((__format__(__printf__, 1, 2))) 129 REQUIRES_SHARED(Locks::mutator_lock_); 130 static void ThrowNoClassDefFoundError(const char* fmt, ...) { 131 va_list args; 132 va_start(args, fmt); 133 Thread* self = Thread::Current(); 134 self->ThrowNewExceptionV("Ljava/lang/NoClassDefFoundError;", fmt, args); 135 va_end(args); 136 } 137 138 static bool HasInitWithString(Thread* self, ClassLinker* class_linker, const char* descriptor) 139 REQUIRES_SHARED(Locks::mutator_lock_) { 140 ArtMethod* method = self->GetCurrentMethod(nullptr); 141 StackHandleScope<1> hs(self); 142 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(method != nullptr ? 143 method->GetDeclaringClass()->GetClassLoader() : nullptr)); 144 ObjPtr<mirror::Class> exception_class = class_linker->FindClass(self, descriptor, class_loader); 145 146 if (exception_class == nullptr) { 147 // No exc class ~ no <init>-with-string. 148 CHECK(self->IsExceptionPending()); 149 self->ClearException(); 150 return false; 151 } 152 153 ArtMethod* exception_init_method = exception_class->FindConstructor( 154 "(Ljava/lang/String;)V", class_linker->GetImagePointerSize()); 155 return exception_init_method != nullptr; 156 } 157 158 static mirror::Object* GetVerifyError(ObjPtr<mirror::Class> c) 159 REQUIRES_SHARED(Locks::mutator_lock_) { 160 ObjPtr<mirror::ClassExt> ext(c->GetExtData()); 161 if (ext == nullptr) { 162 return nullptr; 163 } else { 164 return ext->GetVerifyError(); 165 } 166 } 167 168 // Helper for ThrowEarlierClassFailure. Throws the stored error. 169 static void HandleEarlierVerifyError(Thread* self, 170 ClassLinker* class_linker, 171 ObjPtr<mirror::Class> c) 172 REQUIRES_SHARED(Locks::mutator_lock_) { 173 ObjPtr<mirror::Object> obj = GetVerifyError(c); 174 DCHECK(obj != nullptr); 175 self->AssertNoPendingException(); 176 if (obj->IsClass()) { 177 // Previous error has been stored as class. Create a new exception of that type. 178 179 // It's possible the exception doesn't have a <init>(String). 180 std::string temp; 181 const char* descriptor = obj->AsClass()->GetDescriptor(&temp); 182 183 if (HasInitWithString(self, class_linker, descriptor)) { 184 self->ThrowNewException(descriptor, c->PrettyDescriptor().c_str()); 185 } else { 186 self->ThrowNewException(descriptor, nullptr); 187 } 188 } else { 189 // Previous error has been stored as an instance. Just rethrow. 190 ObjPtr<mirror::Class> throwable_class = 191 self->DecodeJObject(WellKnownClasses::java_lang_Throwable)->AsClass(); 192 ObjPtr<mirror::Class> error_class = obj->GetClass(); 193 CHECK(throwable_class->IsAssignableFrom(error_class)); 194 self->SetException(obj->AsThrowable()); 195 } 196 self->AssertPendingException(); 197 } 198 199 void ClassLinker::ThrowEarlierClassFailure(ObjPtr<mirror::Class> c, bool wrap_in_no_class_def) { 200 // The class failed to initialize on a previous attempt, so we want to throw 201 // a NoClassDefFoundError (v2 2.17.5). The exception to this rule is if we 202 // failed in verification, in which case v2 5.4.1 says we need to re-throw 203 // the previous error. 204 Runtime* const runtime = Runtime::Current(); 205 if (!runtime->IsAotCompiler()) { // Give info if this occurs at runtime. 206 std::string extra; 207 if (GetVerifyError(c) != nullptr) { 208 ObjPtr<mirror::Object> verify_error = GetVerifyError(c); 209 if (verify_error->IsClass()) { 210 extra = mirror::Class::PrettyDescriptor(verify_error->AsClass()); 211 } else { 212 extra = verify_error->AsThrowable()->Dump(); 213 } 214 } 215 LOG(INFO) << "Rejecting re-init on previously-failed class " << c->PrettyClass() 216 << ": " << extra; 217 } 218 219 CHECK(c->IsErroneous()) << c->PrettyClass() << " " << c->GetStatus(); 220 Thread* self = Thread::Current(); 221 if (runtime->IsAotCompiler()) { 222 // At compile time, accurate errors and NCDFE are disabled to speed compilation. 223 ObjPtr<mirror::Throwable> pre_allocated = runtime->GetPreAllocatedNoClassDefFoundError(); 224 self->SetException(pre_allocated); 225 } else { 226 if (GetVerifyError(c) != nullptr) { 227 // Rethrow stored error. 228 HandleEarlierVerifyError(self, this, c); 229 } 230 // TODO This might be wrong if we hit an OOME while allocating the ClassExt. In that case we 231 // might have meant to go down the earlier if statement with the original error but it got 232 // swallowed by the OOM so we end up here. 233 if (GetVerifyError(c) == nullptr || wrap_in_no_class_def) { 234 // If there isn't a recorded earlier error, or this is a repeat throw from initialization, 235 // the top-level exception must be a NoClassDefFoundError. The potentially already pending 236 // exception will be a cause. 237 self->ThrowNewWrappedException("Ljava/lang/NoClassDefFoundError;", 238 c->PrettyDescriptor().c_str()); 239 } 240 } 241 } 242 243 static void VlogClassInitializationFailure(Handle<mirror::Class> klass) 244 REQUIRES_SHARED(Locks::mutator_lock_) { 245 if (VLOG_IS_ON(class_linker)) { 246 std::string temp; 247 LOG(INFO) << "Failed to initialize class " << klass->GetDescriptor(&temp) << " from " 248 << klass->GetLocation() << "\n" << Thread::Current()->GetException()->Dump(); 249 } 250 } 251 252 static void WrapExceptionInInitializer(Handle<mirror::Class> klass) 253 REQUIRES_SHARED(Locks::mutator_lock_) { 254 Thread* self = Thread::Current(); 255 JNIEnv* env = self->GetJniEnv(); 256 257 ScopedLocalRef<jthrowable> cause(env, env->ExceptionOccurred()); 258 CHECK(cause.get() != nullptr); 259 260 // Boot classpath classes should not fail initialization. This is a sanity debug check. This 261 // cannot in general be guaranteed, but in all likelihood leads to breakage down the line. 262 if (klass->GetClassLoader() == nullptr && !Runtime::Current()->IsAotCompiler()) { 263 std::string tmp; 264 LOG(kIsDebugBuild ? FATAL : WARNING) << klass->GetDescriptor(&tmp) << " failed initialization"; 265 } 266 267 env->ExceptionClear(); 268 bool is_error = env->IsInstanceOf(cause.get(), WellKnownClasses::java_lang_Error); 269 env->Throw(cause.get()); 270 271 // We only wrap non-Error exceptions; an Error can just be used as-is. 272 if (!is_error) { 273 self->ThrowNewWrappedException("Ljava/lang/ExceptionInInitializerError;", nullptr); 274 } 275 VlogClassInitializationFailure(klass); 276 } 277 278 // Gap between two fields in object layout. 279 struct FieldGap { 280 uint32_t start_offset; // The offset from the start of the object. 281 uint32_t size; // The gap size of 1, 2, or 4 bytes. 282 }; 283 struct FieldGapsComparator { 284 explicit FieldGapsComparator() { 285 } 286 bool operator() (const FieldGap& lhs, const FieldGap& rhs) 287 NO_THREAD_SAFETY_ANALYSIS { 288 // Sort by gap size, largest first. Secondary sort by starting offset. 289 // Note that the priority queue returns the largest element, so operator() 290 // should return true if lhs is less than rhs. 291 return lhs.size < rhs.size || (lhs.size == rhs.size && lhs.start_offset > rhs.start_offset); 292 } 293 }; 294 typedef std::priority_queue<FieldGap, std::vector<FieldGap>, FieldGapsComparator> FieldGaps; 295 296 // Adds largest aligned gaps to queue of gaps. 297 static void AddFieldGap(uint32_t gap_start, uint32_t gap_end, FieldGaps* gaps) { 298 DCHECK(gaps != nullptr); 299 300 uint32_t current_offset = gap_start; 301 while (current_offset != gap_end) { 302 size_t remaining = gap_end - current_offset; 303 if (remaining >= sizeof(uint32_t) && IsAligned<4>(current_offset)) { 304 gaps->push(FieldGap {current_offset, sizeof(uint32_t)}); 305 current_offset += sizeof(uint32_t); 306 } else if (remaining >= sizeof(uint16_t) && IsAligned<2>(current_offset)) { 307 gaps->push(FieldGap {current_offset, sizeof(uint16_t)}); 308 current_offset += sizeof(uint16_t); 309 } else { 310 gaps->push(FieldGap {current_offset, sizeof(uint8_t)}); 311 current_offset += sizeof(uint8_t); 312 } 313 DCHECK_LE(current_offset, gap_end) << "Overran gap"; 314 } 315 } 316 // Shuffle fields forward, making use of gaps whenever possible. 317 template<int n> 318 static void ShuffleForward(size_t* current_field_idx, 319 MemberOffset* field_offset, 320 std::deque<ArtField*>* grouped_and_sorted_fields, 321 FieldGaps* gaps) 322 REQUIRES_SHARED(Locks::mutator_lock_) { 323 DCHECK(current_field_idx != nullptr); 324 DCHECK(grouped_and_sorted_fields != nullptr); 325 DCHECK(gaps != nullptr); 326 DCHECK(field_offset != nullptr); 327 328 DCHECK(IsPowerOfTwo(n)); 329 while (!grouped_and_sorted_fields->empty()) { 330 ArtField* field = grouped_and_sorted_fields->front(); 331 Primitive::Type type = field->GetTypeAsPrimitiveType(); 332 if (Primitive::ComponentSize(type) < n) { 333 break; 334 } 335 if (!IsAligned<n>(field_offset->Uint32Value())) { 336 MemberOffset old_offset = *field_offset; 337 *field_offset = MemberOffset(RoundUp(field_offset->Uint32Value(), n)); 338 AddFieldGap(old_offset.Uint32Value(), field_offset->Uint32Value(), gaps); 339 } 340 CHECK(type != Primitive::kPrimNot) << field->PrettyField(); // should be primitive types 341 grouped_and_sorted_fields->pop_front(); 342 if (!gaps->empty() && gaps->top().size >= n) { 343 FieldGap gap = gaps->top(); 344 gaps->pop(); 345 DCHECK_ALIGNED(gap.start_offset, n); 346 field->SetOffset(MemberOffset(gap.start_offset)); 347 if (gap.size > n) { 348 AddFieldGap(gap.start_offset + n, gap.start_offset + gap.size, gaps); 349 } 350 } else { 351 DCHECK_ALIGNED(field_offset->Uint32Value(), n); 352 field->SetOffset(*field_offset); 353 *field_offset = MemberOffset(field_offset->Uint32Value() + n); 354 } 355 ++(*current_field_idx); 356 } 357 } 358 359 ClassLinker::ClassLinker(InternTable* intern_table) 360 : boot_class_table_(new ClassTable()), 361 failed_dex_cache_class_lookups_(0), 362 class_roots_(nullptr), 363 array_iftable_(nullptr), 364 find_array_class_cache_next_victim_(0), 365 init_done_(false), 366 log_new_roots_(false), 367 intern_table_(intern_table), 368 quick_resolution_trampoline_(nullptr), 369 quick_imt_conflict_trampoline_(nullptr), 370 quick_generic_jni_trampoline_(nullptr), 371 quick_to_interpreter_bridge_trampoline_(nullptr), 372 image_pointer_size_(kRuntimePointerSize), 373 cha_(Runtime::Current()->IsAotCompiler() ? nullptr : new ClassHierarchyAnalysis()) { 374 // For CHA disabled during Aot, see b/34193647. 375 376 CHECK(intern_table_ != nullptr); 377 static_assert(kFindArrayCacheSize == arraysize(find_array_class_cache_), 378 "Array cache size wrong."); 379 std::fill_n(find_array_class_cache_, kFindArrayCacheSize, GcRoot<mirror::Class>(nullptr)); 380 } 381 382 void ClassLinker::CheckSystemClass(Thread* self, Handle<mirror::Class> c1, const char* descriptor) { 383 ObjPtr<mirror::Class> c2 = FindSystemClass(self, descriptor); 384 if (c2 == nullptr) { 385 LOG(FATAL) << "Could not find class " << descriptor; 386 UNREACHABLE(); 387 } 388 if (c1.Get() != c2) { 389 std::ostringstream os1, os2; 390 c1->DumpClass(os1, mirror::Class::kDumpClassFullDetail); 391 c2->DumpClass(os2, mirror::Class::kDumpClassFullDetail); 392 LOG(FATAL) << "InitWithoutImage: Class mismatch for " << descriptor 393 << ". This is most likely the result of a broken build. Make sure that " 394 << "libcore and art projects match.\n\n" 395 << os1.str() << "\n\n" << os2.str(); 396 UNREACHABLE(); 397 } 398 } 399 400 bool ClassLinker::InitWithoutImage(std::vector<std::unique_ptr<const DexFile>> boot_class_path, 401 std::string* error_msg) { 402 VLOG(startup) << "ClassLinker::Init"; 403 404 Thread* const self = Thread::Current(); 405 Runtime* const runtime = Runtime::Current(); 406 gc::Heap* const heap = runtime->GetHeap(); 407 408 CHECK(!heap->HasBootImageSpace()) << "Runtime has image. We should use it."; 409 CHECK(!init_done_); 410 411 // Use the pointer size from the runtime since we are probably creating the image. 412 image_pointer_size_ = InstructionSetPointerSize(runtime->GetInstructionSet()); 413 414 // java_lang_Class comes first, it's needed for AllocClass 415 // The GC can't handle an object with a null class since we can't get the size of this object. 416 heap->IncrementDisableMovingGC(self); 417 StackHandleScope<64> hs(self); // 64 is picked arbitrarily. 418 auto class_class_size = mirror::Class::ClassClassSize(image_pointer_size_); 419 Handle<mirror::Class> java_lang_Class(hs.NewHandle(down_cast<mirror::Class*>( 420 heap->AllocNonMovableObject<true>(self, nullptr, class_class_size, VoidFunctor())))); 421 CHECK(java_lang_Class != nullptr); 422 mirror::Class::SetClassClass(java_lang_Class.Get()); 423 java_lang_Class->SetClass(java_lang_Class.Get()); 424 if (kUseBakerReadBarrier) { 425 java_lang_Class->AssertReadBarrierState(); 426 } 427 java_lang_Class->SetClassSize(class_class_size); 428 java_lang_Class->SetPrimitiveType(Primitive::kPrimNot); 429 heap->DecrementDisableMovingGC(self); 430 // AllocClass(ObjPtr<mirror::Class>) can now be used 431 432 // Class[] is used for reflection support. 433 auto class_array_class_size = mirror::ObjectArray<mirror::Class>::ClassSize(image_pointer_size_); 434 Handle<mirror::Class> class_array_class(hs.NewHandle( 435 AllocClass(self, java_lang_Class.Get(), class_array_class_size))); 436 class_array_class->SetComponentType(java_lang_Class.Get()); 437 438 // java_lang_Object comes next so that object_array_class can be created. 439 Handle<mirror::Class> java_lang_Object(hs.NewHandle( 440 AllocClass(self, java_lang_Class.Get(), mirror::Object::ClassSize(image_pointer_size_)))); 441 CHECK(java_lang_Object != nullptr); 442 // backfill Object as the super class of Class. 443 java_lang_Class->SetSuperClass(java_lang_Object.Get()); 444 mirror::Class::SetStatus(java_lang_Object, mirror::Class::kStatusLoaded, self); 445 446 java_lang_Object->SetObjectSize(sizeof(mirror::Object)); 447 // Allocate in non-movable so that it's possible to check if a JNI weak global ref has been 448 // cleared without triggering the read barrier and unintentionally mark the sentinel alive. 449 runtime->SetSentinel(heap->AllocNonMovableObject<true>(self, 450 java_lang_Object.Get(), 451 java_lang_Object->GetObjectSize(), 452 VoidFunctor())); 453 454 // Object[] next to hold class roots. 455 Handle<mirror::Class> object_array_class(hs.NewHandle( 456 AllocClass(self, java_lang_Class.Get(), 457 mirror::ObjectArray<mirror::Object>::ClassSize(image_pointer_size_)))); 458 object_array_class->SetComponentType(java_lang_Object.Get()); 459 460 // Setup the char (primitive) class to be used for char[]. 461 Handle<mirror::Class> char_class(hs.NewHandle( 462 AllocClass(self, java_lang_Class.Get(), 463 mirror::Class::PrimitiveClassSize(image_pointer_size_)))); 464 // The primitive char class won't be initialized by 465 // InitializePrimitiveClass until line 459, but strings (and 466 // internal char arrays) will be allocated before that and the 467 // component size, which is computed from the primitive type, needs 468 // to be set here. 469 char_class->SetPrimitiveType(Primitive::kPrimChar); 470 471 // Setup the char[] class to be used for String. 472 Handle<mirror::Class> char_array_class(hs.NewHandle( 473 AllocClass(self, java_lang_Class.Get(), mirror::Array::ClassSize(image_pointer_size_)))); 474 char_array_class->SetComponentType(char_class.Get()); 475 mirror::CharArray::SetArrayClass(char_array_class.Get()); 476 477 // Setup String. 478 Handle<mirror::Class> java_lang_String(hs.NewHandle( 479 AllocClass(self, java_lang_Class.Get(), mirror::String::ClassSize(image_pointer_size_)))); 480 java_lang_String->SetStringClass(); 481 mirror::String::SetClass(java_lang_String.Get()); 482 mirror::Class::SetStatus(java_lang_String, mirror::Class::kStatusResolved, self); 483 484 // Setup java.lang.ref.Reference. 485 Handle<mirror::Class> java_lang_ref_Reference(hs.NewHandle( 486 AllocClass(self, java_lang_Class.Get(), mirror::Reference::ClassSize(image_pointer_size_)))); 487 mirror::Reference::SetClass(java_lang_ref_Reference.Get()); 488 java_lang_ref_Reference->SetObjectSize(mirror::Reference::InstanceSize()); 489 mirror::Class::SetStatus(java_lang_ref_Reference, mirror::Class::kStatusResolved, self); 490 491 // Create storage for root classes, save away our work so far (requires descriptors). 492 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class>>( 493 mirror::ObjectArray<mirror::Class>::Alloc(self, object_array_class.Get(), 494 kClassRootsMax)); 495 CHECK(!class_roots_.IsNull()); 496 SetClassRoot(kJavaLangClass, java_lang_Class.Get()); 497 SetClassRoot(kJavaLangObject, java_lang_Object.Get()); 498 SetClassRoot(kClassArrayClass, class_array_class.Get()); 499 SetClassRoot(kObjectArrayClass, object_array_class.Get()); 500 SetClassRoot(kCharArrayClass, char_array_class.Get()); 501 SetClassRoot(kJavaLangString, java_lang_String.Get()); 502 SetClassRoot(kJavaLangRefReference, java_lang_ref_Reference.Get()); 503 504 // Fill in the empty iftable. Needs to be done after the kObjectArrayClass root is set. 505 java_lang_Object->SetIfTable(AllocIfTable(self, 0)); 506 507 // Setup the primitive type classes. 508 SetClassRoot(kPrimitiveBoolean, CreatePrimitiveClass(self, Primitive::kPrimBoolean)); 509 SetClassRoot(kPrimitiveByte, CreatePrimitiveClass(self, Primitive::kPrimByte)); 510 SetClassRoot(kPrimitiveShort, CreatePrimitiveClass(self, Primitive::kPrimShort)); 511 SetClassRoot(kPrimitiveInt, CreatePrimitiveClass(self, Primitive::kPrimInt)); 512 SetClassRoot(kPrimitiveLong, CreatePrimitiveClass(self, Primitive::kPrimLong)); 513 SetClassRoot(kPrimitiveFloat, CreatePrimitiveClass(self, Primitive::kPrimFloat)); 514 SetClassRoot(kPrimitiveDouble, CreatePrimitiveClass(self, Primitive::kPrimDouble)); 515 SetClassRoot(kPrimitiveVoid, CreatePrimitiveClass(self, Primitive::kPrimVoid)); 516 517 // Create array interface entries to populate once we can load system classes. 518 array_iftable_ = GcRoot<mirror::IfTable>(AllocIfTable(self, 2)); 519 520 // Create int array type for AllocDexCache (done in AppendToBootClassPath). 521 Handle<mirror::Class> int_array_class(hs.NewHandle( 522 AllocClass(self, java_lang_Class.Get(), mirror::Array::ClassSize(image_pointer_size_)))); 523 int_array_class->SetComponentType(GetClassRoot(kPrimitiveInt)); 524 mirror::IntArray::SetArrayClass(int_array_class.Get()); 525 SetClassRoot(kIntArrayClass, int_array_class.Get()); 526 527 // Create long array type for AllocDexCache (done in AppendToBootClassPath). 528 Handle<mirror::Class> long_array_class(hs.NewHandle( 529 AllocClass(self, java_lang_Class.Get(), mirror::Array::ClassSize(image_pointer_size_)))); 530 long_array_class->SetComponentType(GetClassRoot(kPrimitiveLong)); 531 mirror::LongArray::SetArrayClass(long_array_class.Get()); 532 SetClassRoot(kLongArrayClass, long_array_class.Get()); 533 534 // now that these are registered, we can use AllocClass() and AllocObjectArray 535 536 // Set up DexCache. This cannot be done later since AppendToBootClassPath calls AllocDexCache. 537 Handle<mirror::Class> java_lang_DexCache(hs.NewHandle( 538 AllocClass(self, java_lang_Class.Get(), mirror::DexCache::ClassSize(image_pointer_size_)))); 539 SetClassRoot(kJavaLangDexCache, java_lang_DexCache.Get()); 540 java_lang_DexCache->SetDexCacheClass(); 541 java_lang_DexCache->SetObjectSize(mirror::DexCache::InstanceSize()); 542 mirror::Class::SetStatus(java_lang_DexCache, mirror::Class::kStatusResolved, self); 543 544 545 // Setup dalvik.system.ClassExt 546 Handle<mirror::Class> dalvik_system_ClassExt(hs.NewHandle( 547 AllocClass(self, java_lang_Class.Get(), mirror::ClassExt::ClassSize(image_pointer_size_)))); 548 SetClassRoot(kDalvikSystemClassExt, dalvik_system_ClassExt.Get()); 549 mirror::ClassExt::SetClass(dalvik_system_ClassExt.Get()); 550 mirror::Class::SetStatus(dalvik_system_ClassExt, mirror::Class::kStatusResolved, self); 551 552 // Set up array classes for string, field, method 553 Handle<mirror::Class> object_array_string(hs.NewHandle( 554 AllocClass(self, java_lang_Class.Get(), 555 mirror::ObjectArray<mirror::String>::ClassSize(image_pointer_size_)))); 556 object_array_string->SetComponentType(java_lang_String.Get()); 557 SetClassRoot(kJavaLangStringArrayClass, object_array_string.Get()); 558 559 LinearAlloc* linear_alloc = runtime->GetLinearAlloc(); 560 // Create runtime resolution and imt conflict methods. 561 runtime->SetResolutionMethod(runtime->CreateResolutionMethod()); 562 runtime->SetImtConflictMethod(runtime->CreateImtConflictMethod(linear_alloc)); 563 runtime->SetImtUnimplementedMethod(runtime->CreateImtConflictMethod(linear_alloc)); 564 565 // Setup boot_class_path_ and register class_path now that we can use AllocObjectArray to create 566 // DexCache instances. Needs to be after String, Field, Method arrays since AllocDexCache uses 567 // these roots. 568 if (boot_class_path.empty()) { 569 *error_msg = "Boot classpath is empty."; 570 return false; 571 } 572 for (auto& dex_file : boot_class_path) { 573 if (dex_file.get() == nullptr) { 574 *error_msg = "Null dex file."; 575 return false; 576 } 577 AppendToBootClassPath(self, *dex_file); 578 boot_dex_files_.push_back(std::move(dex_file)); 579 } 580 581 // now we can use FindSystemClass 582 583 // run char class through InitializePrimitiveClass to finish init 584 InitializePrimitiveClass(char_class.Get(), Primitive::kPrimChar); 585 SetClassRoot(kPrimitiveChar, char_class.Get()); // needs descriptor 586 587 // Set up GenericJNI entrypoint. That is mainly a hack for common_compiler_test.h so that 588 // we do not need friend classes or a publicly exposed setter. 589 quick_generic_jni_trampoline_ = GetQuickGenericJniStub(); 590 if (!runtime->IsAotCompiler()) { 591 // We need to set up the generic trampolines since we don't have an image. 592 quick_resolution_trampoline_ = GetQuickResolutionStub(); 593 quick_imt_conflict_trampoline_ = GetQuickImtConflictStub(); 594 quick_to_interpreter_bridge_trampoline_ = GetQuickToInterpreterBridge(); 595 } 596 597 // Object, String, ClassExt and DexCache need to be rerun through FindSystemClass to finish init 598 mirror::Class::SetStatus(java_lang_Object, mirror::Class::kStatusNotReady, self); 599 CheckSystemClass(self, java_lang_Object, "Ljava/lang/Object;"); 600 CHECK_EQ(java_lang_Object->GetObjectSize(), mirror::Object::InstanceSize()); 601 mirror::Class::SetStatus(java_lang_String, mirror::Class::kStatusNotReady, self); 602 CheckSystemClass(self, java_lang_String, "Ljava/lang/String;"); 603 mirror::Class::SetStatus(java_lang_DexCache, mirror::Class::kStatusNotReady, self); 604 CheckSystemClass(self, java_lang_DexCache, "Ljava/lang/DexCache;"); 605 CHECK_EQ(java_lang_DexCache->GetObjectSize(), mirror::DexCache::InstanceSize()); 606 mirror::Class::SetStatus(dalvik_system_ClassExt, mirror::Class::kStatusNotReady, self); 607 CheckSystemClass(self, dalvik_system_ClassExt, "Ldalvik/system/ClassExt;"); 608 CHECK_EQ(dalvik_system_ClassExt->GetObjectSize(), mirror::ClassExt::InstanceSize()); 609 610 // Setup the primitive array type classes - can't be done until Object has a vtable. 611 SetClassRoot(kBooleanArrayClass, FindSystemClass(self, "[Z")); 612 mirror::BooleanArray::SetArrayClass(GetClassRoot(kBooleanArrayClass)); 613 614 SetClassRoot(kByteArrayClass, FindSystemClass(self, "[B")); 615 mirror::ByteArray::SetArrayClass(GetClassRoot(kByteArrayClass)); 616 617 CheckSystemClass(self, char_array_class, "[C"); 618 619 SetClassRoot(kShortArrayClass, FindSystemClass(self, "[S")); 620 mirror::ShortArray::SetArrayClass(GetClassRoot(kShortArrayClass)); 621 622 CheckSystemClass(self, int_array_class, "[I"); 623 CheckSystemClass(self, long_array_class, "[J"); 624 625 SetClassRoot(kFloatArrayClass, FindSystemClass(self, "[F")); 626 mirror::FloatArray::SetArrayClass(GetClassRoot(kFloatArrayClass)); 627 628 SetClassRoot(kDoubleArrayClass, FindSystemClass(self, "[D")); 629 mirror::DoubleArray::SetArrayClass(GetClassRoot(kDoubleArrayClass)); 630 631 // Run Class through FindSystemClass. This initializes the dex_cache_ fields and register it 632 // in class_table_. 633 CheckSystemClass(self, java_lang_Class, "Ljava/lang/Class;"); 634 635 CheckSystemClass(self, class_array_class, "[Ljava/lang/Class;"); 636 CheckSystemClass(self, object_array_class, "[Ljava/lang/Object;"); 637 638 // Setup the single, global copy of "iftable". 639 auto java_lang_Cloneable = hs.NewHandle(FindSystemClass(self, "Ljava/lang/Cloneable;")); 640 CHECK(java_lang_Cloneable != nullptr); 641 auto java_io_Serializable = hs.NewHandle(FindSystemClass(self, "Ljava/io/Serializable;")); 642 CHECK(java_io_Serializable != nullptr); 643 // We assume that Cloneable/Serializable don't have superinterfaces -- normally we'd have to 644 // crawl up and explicitly list all of the supers as well. 645 array_iftable_.Read()->SetInterface(0, java_lang_Cloneable.Get()); 646 array_iftable_.Read()->SetInterface(1, java_io_Serializable.Get()); 647 648 // Sanity check Class[] and Object[]'s interfaces. GetDirectInterface may cause thread 649 // suspension. 650 CHECK_EQ(java_lang_Cloneable.Get(), 651 mirror::Class::GetDirectInterface(self, class_array_class.Get(), 0)); 652 CHECK_EQ(java_io_Serializable.Get(), 653 mirror::Class::GetDirectInterface(self, class_array_class.Get(), 1)); 654 CHECK_EQ(java_lang_Cloneable.Get(), 655 mirror::Class::GetDirectInterface(self, object_array_class.Get(), 0)); 656 CHECK_EQ(java_io_Serializable.Get(), 657 mirror::Class::GetDirectInterface(self, object_array_class.Get(), 1)); 658 659 CHECK_EQ(object_array_string.Get(), 660 FindSystemClass(self, GetClassRootDescriptor(kJavaLangStringArrayClass))); 661 662 // End of special init trickery, all subsequent classes may be loaded via FindSystemClass. 663 664 // Create java.lang.reflect.Proxy root. 665 SetClassRoot(kJavaLangReflectProxy, FindSystemClass(self, "Ljava/lang/reflect/Proxy;")); 666 667 // Create java.lang.reflect.Field.class root. 668 auto* class_root = FindSystemClass(self, "Ljava/lang/reflect/Field;"); 669 CHECK(class_root != nullptr); 670 SetClassRoot(kJavaLangReflectField, class_root); 671 mirror::Field::SetClass(class_root); 672 673 // Create java.lang.reflect.Field array root. 674 class_root = FindSystemClass(self, "[Ljava/lang/reflect/Field;"); 675 CHECK(class_root != nullptr); 676 SetClassRoot(kJavaLangReflectFieldArrayClass, class_root); 677 mirror::Field::SetArrayClass(class_root); 678 679 // Create java.lang.reflect.Constructor.class root and array root. 680 class_root = FindSystemClass(self, "Ljava/lang/reflect/Constructor;"); 681 CHECK(class_root != nullptr); 682 SetClassRoot(kJavaLangReflectConstructor, class_root); 683 mirror::Constructor::SetClass(class_root); 684 class_root = FindSystemClass(self, "[Ljava/lang/reflect/Constructor;"); 685 CHECK(class_root != nullptr); 686 SetClassRoot(kJavaLangReflectConstructorArrayClass, class_root); 687 mirror::Constructor::SetArrayClass(class_root); 688 689 // Create java.lang.reflect.Method.class root and array root. 690 class_root = FindSystemClass(self, "Ljava/lang/reflect/Method;"); 691 CHECK(class_root != nullptr); 692 SetClassRoot(kJavaLangReflectMethod, class_root); 693 mirror::Method::SetClass(class_root); 694 class_root = FindSystemClass(self, "[Ljava/lang/reflect/Method;"); 695 CHECK(class_root != nullptr); 696 SetClassRoot(kJavaLangReflectMethodArrayClass, class_root); 697 mirror::Method::SetArrayClass(class_root); 698 699 // Create java.lang.invoke.MethodType.class root 700 class_root = FindSystemClass(self, "Ljava/lang/invoke/MethodType;"); 701 CHECK(class_root != nullptr); 702 SetClassRoot(kJavaLangInvokeMethodType, class_root); 703 mirror::MethodType::SetClass(class_root); 704 705 // Create java.lang.invoke.MethodHandleImpl.class root 706 class_root = FindSystemClass(self, "Ljava/lang/invoke/MethodHandleImpl;"); 707 CHECK(class_root != nullptr); 708 SetClassRoot(kJavaLangInvokeMethodHandleImpl, class_root); 709 mirror::MethodHandleImpl::SetClass(class_root); 710 711 // Create java.lang.invoke.MethodHandles.Lookup.class root 712 class_root = FindSystemClass(self, "Ljava/lang/invoke/MethodHandles$Lookup;"); 713 CHECK(class_root != nullptr); 714 SetClassRoot(kJavaLangInvokeMethodHandlesLookup, class_root); 715 mirror::MethodHandlesLookup::SetClass(class_root); 716 717 // Create java.lang.invoke.CallSite.class root 718 class_root = FindSystemClass(self, "Ljava/lang/invoke/CallSite;"); 719 CHECK(class_root != nullptr); 720 SetClassRoot(kJavaLangInvokeCallSite, class_root); 721 mirror::CallSite::SetClass(class_root); 722 723 class_root = FindSystemClass(self, "Ldalvik/system/EmulatedStackFrame;"); 724 CHECK(class_root != nullptr); 725 SetClassRoot(kDalvikSystemEmulatedStackFrame, class_root); 726 mirror::EmulatedStackFrame::SetClass(class_root); 727 728 // java.lang.ref classes need to be specially flagged, but otherwise are normal classes 729 // finish initializing Reference class 730 mirror::Class::SetStatus(java_lang_ref_Reference, mirror::Class::kStatusNotReady, self); 731 CheckSystemClass(self, java_lang_ref_Reference, "Ljava/lang/ref/Reference;"); 732 CHECK_EQ(java_lang_ref_Reference->GetObjectSize(), mirror::Reference::InstanceSize()); 733 CHECK_EQ(java_lang_ref_Reference->GetClassSize(), 734 mirror::Reference::ClassSize(image_pointer_size_)); 735 class_root = FindSystemClass(self, "Ljava/lang/ref/FinalizerReference;"); 736 CHECK_EQ(class_root->GetClassFlags(), mirror::kClassFlagNormal); 737 class_root->SetClassFlags(class_root->GetClassFlags() | mirror::kClassFlagFinalizerReference); 738 class_root = FindSystemClass(self, "Ljava/lang/ref/PhantomReference;"); 739 CHECK_EQ(class_root->GetClassFlags(), mirror::kClassFlagNormal); 740 class_root->SetClassFlags(class_root->GetClassFlags() | mirror::kClassFlagPhantomReference); 741 class_root = FindSystemClass(self, "Ljava/lang/ref/SoftReference;"); 742 CHECK_EQ(class_root->GetClassFlags(), mirror::kClassFlagNormal); 743 class_root->SetClassFlags(class_root->GetClassFlags() | mirror::kClassFlagSoftReference); 744 class_root = FindSystemClass(self, "Ljava/lang/ref/WeakReference;"); 745 CHECK_EQ(class_root->GetClassFlags(), mirror::kClassFlagNormal); 746 class_root->SetClassFlags(class_root->GetClassFlags() | mirror::kClassFlagWeakReference); 747 748 // Setup the ClassLoader, verifying the object_size_. 749 class_root = FindSystemClass(self, "Ljava/lang/ClassLoader;"); 750 class_root->SetClassLoaderClass(); 751 CHECK_EQ(class_root->GetObjectSize(), mirror::ClassLoader::InstanceSize()); 752 SetClassRoot(kJavaLangClassLoader, class_root); 753 754 // Set up java.lang.Throwable, java.lang.ClassNotFoundException, and 755 // java.lang.StackTraceElement as a convenience. 756 SetClassRoot(kJavaLangThrowable, FindSystemClass(self, "Ljava/lang/Throwable;")); 757 mirror::Throwable::SetClass(GetClassRoot(kJavaLangThrowable)); 758 SetClassRoot(kJavaLangClassNotFoundException, 759 FindSystemClass(self, "Ljava/lang/ClassNotFoundException;")); 760 SetClassRoot(kJavaLangStackTraceElement, FindSystemClass(self, "Ljava/lang/StackTraceElement;")); 761 SetClassRoot(kJavaLangStackTraceElementArrayClass, 762 FindSystemClass(self, "[Ljava/lang/StackTraceElement;")); 763 mirror::StackTraceElement::SetClass(GetClassRoot(kJavaLangStackTraceElement)); 764 765 // Create conflict tables that depend on the class linker. 766 runtime->FixupConflictTables(); 767 768 FinishInit(self); 769 770 VLOG(startup) << "ClassLinker::InitFromCompiler exiting"; 771 772 return true; 773 } 774 775 void ClassLinker::FinishInit(Thread* self) { 776 VLOG(startup) << "ClassLinker::FinishInit entering"; 777 778 // Let the heap know some key offsets into java.lang.ref instances 779 // Note: we hard code the field indexes here rather than using FindInstanceField 780 // as the types of the field can't be resolved prior to the runtime being 781 // fully initialized 782 StackHandleScope<2> hs(self); 783 Handle<mirror::Class> java_lang_ref_Reference = hs.NewHandle(GetClassRoot(kJavaLangRefReference)); 784 Handle<mirror::Class> java_lang_ref_FinalizerReference = 785 hs.NewHandle(FindSystemClass(self, "Ljava/lang/ref/FinalizerReference;")); 786 787 ArtField* pendingNext = java_lang_ref_Reference->GetInstanceField(0); 788 CHECK_STREQ(pendingNext->GetName(), "pendingNext"); 789 CHECK_STREQ(pendingNext->GetTypeDescriptor(), "Ljava/lang/ref/Reference;"); 790 791 ArtField* queue = java_lang_ref_Reference->GetInstanceField(1); 792 CHECK_STREQ(queue->GetName(), "queue"); 793 CHECK_STREQ(queue->GetTypeDescriptor(), "Ljava/lang/ref/ReferenceQueue;"); 794 795 ArtField* queueNext = java_lang_ref_Reference->GetInstanceField(2); 796 CHECK_STREQ(queueNext->GetName(), "queueNext"); 797 CHECK_STREQ(queueNext->GetTypeDescriptor(), "Ljava/lang/ref/Reference;"); 798 799 ArtField* referent = java_lang_ref_Reference->GetInstanceField(3); 800 CHECK_STREQ(referent->GetName(), "referent"); 801 CHECK_STREQ(referent->GetTypeDescriptor(), "Ljava/lang/Object;"); 802 803 ArtField* zombie = java_lang_ref_FinalizerReference->GetInstanceField(2); 804 CHECK_STREQ(zombie->GetName(), "zombie"); 805 CHECK_STREQ(zombie->GetTypeDescriptor(), "Ljava/lang/Object;"); 806 807 // ensure all class_roots_ are initialized 808 for (size_t i = 0; i < kClassRootsMax; i++) { 809 ClassRoot class_root = static_cast<ClassRoot>(i); 810 ObjPtr<mirror::Class> klass = GetClassRoot(class_root); 811 CHECK(klass != nullptr); 812 DCHECK(klass->IsArrayClass() || klass->IsPrimitive() || klass->GetDexCache() != nullptr); 813 // note SetClassRoot does additional validation. 814 // if possible add new checks there to catch errors early 815 } 816 817 CHECK(!array_iftable_.IsNull()); 818 819 // disable the slow paths in FindClass and CreatePrimitiveClass now 820 // that Object, Class, and Object[] are setup 821 init_done_ = true; 822 823 VLOG(startup) << "ClassLinker::FinishInit exiting"; 824 } 825 826 void ClassLinker::RunRootClinits() { 827 Thread* self = Thread::Current(); 828 for (size_t i = 0; i < ClassLinker::kClassRootsMax; ++i) { 829 ObjPtr<mirror::Class> c = GetClassRoot(ClassRoot(i)); 830 if (!c->IsArrayClass() && !c->IsPrimitive()) { 831 StackHandleScope<1> hs(self); 832 Handle<mirror::Class> h_class(hs.NewHandle(GetClassRoot(ClassRoot(i)))); 833 EnsureInitialized(self, h_class, true, true); 834 self->AssertNoPendingException(); 835 } 836 } 837 } 838 839 // Set image methods' entry point to interpreter. 840 class SetInterpreterEntrypointArtMethodVisitor : public ArtMethodVisitor { 841 public: 842 explicit SetInterpreterEntrypointArtMethodVisitor(PointerSize image_pointer_size) 843 : image_pointer_size_(image_pointer_size) {} 844 845 void Visit(ArtMethod* method) OVERRIDE REQUIRES_SHARED(Locks::mutator_lock_) { 846 if (kIsDebugBuild && !method->IsRuntimeMethod()) { 847 CHECK(method->GetDeclaringClass() != nullptr); 848 } 849 if (!method->IsNative() && !method->IsRuntimeMethod() && !method->IsResolutionMethod()) { 850 method->SetEntryPointFromQuickCompiledCodePtrSize(GetQuickToInterpreterBridge(), 851 image_pointer_size_); 852 } 853 } 854 855 private: 856 const PointerSize image_pointer_size_; 857 858 DISALLOW_COPY_AND_ASSIGN(SetInterpreterEntrypointArtMethodVisitor); 859 }; 860 861 struct TrampolineCheckData { 862 const void* quick_resolution_trampoline; 863 const void* quick_imt_conflict_trampoline; 864 const void* quick_generic_jni_trampoline; 865 const void* quick_to_interpreter_bridge_trampoline; 866 PointerSize pointer_size; 867 ArtMethod* m; 868 bool error; 869 }; 870 871 bool ClassLinker::InitFromBootImage(std::string* error_msg) { 872 VLOG(startup) << __FUNCTION__ << " entering"; 873 CHECK(!init_done_); 874 875 Runtime* const runtime = Runtime::Current(); 876 Thread* const self = Thread::Current(); 877 gc::Heap* const heap = runtime->GetHeap(); 878 std::vector<gc::space::ImageSpace*> spaces = heap->GetBootImageSpaces(); 879 CHECK(!spaces.empty()); 880 uint32_t pointer_size_unchecked = spaces[0]->GetImageHeader().GetPointerSizeUnchecked(); 881 if (!ValidPointerSize(pointer_size_unchecked)) { 882 *error_msg = StringPrintf("Invalid image pointer size: %u", pointer_size_unchecked); 883 return false; 884 } 885 image_pointer_size_ = spaces[0]->GetImageHeader().GetPointerSize(); 886 if (!runtime->IsAotCompiler()) { 887 // Only the Aot compiler supports having an image with a different pointer size than the 888 // runtime. This happens on the host for compiling 32 bit tests since we use a 64 bit libart 889 // compiler. We may also use 32 bit dex2oat on a system with 64 bit apps. 890 if (image_pointer_size_ != kRuntimePointerSize) { 891 *error_msg = StringPrintf("Runtime must use current image pointer size: %zu vs %zu", 892 static_cast<size_t>(image_pointer_size_), 893 sizeof(void*)); 894 return false; 895 } 896 } 897 std::vector<const OatFile*> oat_files = 898 runtime->GetOatFileManager().RegisterImageOatFiles(spaces); 899 DCHECK(!oat_files.empty()); 900 const OatHeader& default_oat_header = oat_files[0]->GetOatHeader(); 901 CHECK_EQ(default_oat_header.GetImageFileLocationOatDataBegin(), 0U); 902 const char* image_file_location = oat_files[0]->GetOatHeader(). 903 GetStoreValueByKey(OatHeader::kImageLocationKey); 904 CHECK(image_file_location == nullptr || *image_file_location == 0); 905 quick_resolution_trampoline_ = default_oat_header.GetQuickResolutionTrampoline(); 906 quick_imt_conflict_trampoline_ = default_oat_header.GetQuickImtConflictTrampoline(); 907 quick_generic_jni_trampoline_ = default_oat_header.GetQuickGenericJniTrampoline(); 908 quick_to_interpreter_bridge_trampoline_ = default_oat_header.GetQuickToInterpreterBridge(); 909 if (kIsDebugBuild) { 910 // Check that the other images use the same trampoline. 911 for (size_t i = 1; i < oat_files.size(); ++i) { 912 const OatHeader& ith_oat_header = oat_files[i]->GetOatHeader(); 913 const void* ith_quick_resolution_trampoline = 914 ith_oat_header.GetQuickResolutionTrampoline(); 915 const void* ith_quick_imt_conflict_trampoline = 916 ith_oat_header.GetQuickImtConflictTrampoline(); 917 const void* ith_quick_generic_jni_trampoline = 918 ith_oat_header.GetQuickGenericJniTrampoline(); 919 const void* ith_quick_to_interpreter_bridge_trampoline = 920 ith_oat_header.GetQuickToInterpreterBridge(); 921 if (ith_quick_resolution_trampoline != quick_resolution_trampoline_ || 922 ith_quick_imt_conflict_trampoline != quick_imt_conflict_trampoline_ || 923 ith_quick_generic_jni_trampoline != quick_generic_jni_trampoline_ || 924 ith_quick_to_interpreter_bridge_trampoline != quick_to_interpreter_bridge_trampoline_) { 925 // Make sure that all methods in this image do not contain those trampolines as 926 // entrypoints. Otherwise the class-linker won't be able to work with a single set. 927 TrampolineCheckData data; 928 data.error = false; 929 data.pointer_size = GetImagePointerSize(); 930 data.quick_resolution_trampoline = ith_quick_resolution_trampoline; 931 data.quick_imt_conflict_trampoline = ith_quick_imt_conflict_trampoline; 932 data.quick_generic_jni_trampoline = ith_quick_generic_jni_trampoline; 933 data.quick_to_interpreter_bridge_trampoline = ith_quick_to_interpreter_bridge_trampoline; 934 ReaderMutexLock mu(self, *Locks::heap_bitmap_lock_); 935 auto visitor = [&](mirror::Object* obj) REQUIRES_SHARED(Locks::mutator_lock_) { 936 if (obj->IsClass()) { 937 ObjPtr<mirror::Class> klass = obj->AsClass(); 938 for (ArtMethod& m : klass->GetMethods(data.pointer_size)) { 939 const void* entrypoint = 940 m.GetEntryPointFromQuickCompiledCodePtrSize(data.pointer_size); 941 if (entrypoint == data.quick_resolution_trampoline || 942 entrypoint == data.quick_imt_conflict_trampoline || 943 entrypoint == data.quick_generic_jni_trampoline || 944 entrypoint == data.quick_to_interpreter_bridge_trampoline) { 945 data.m = &m; 946 data.error = true; 947 return; 948 } 949 } 950 } 951 }; 952 spaces[i]->GetLiveBitmap()->Walk(visitor); 953 if (data.error) { 954 ArtMethod* m = data.m; 955 LOG(ERROR) << "Found a broken ArtMethod: " << ArtMethod::PrettyMethod(m); 956 *error_msg = "Found an ArtMethod with a bad entrypoint"; 957 return false; 958 } 959 } 960 } 961 } 962 963 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class>>( 964 down_cast<mirror::ObjectArray<mirror::Class>*>( 965 spaces[0]->GetImageHeader().GetImageRoot(ImageHeader::kClassRoots))); 966 mirror::Class::SetClassClass(class_roots_.Read()->Get(kJavaLangClass)); 967 968 // Special case of setting up the String class early so that we can test arbitrary objects 969 // as being Strings or not 970 mirror::String::SetClass(GetClassRoot(kJavaLangString)); 971 972 ObjPtr<mirror::Class> java_lang_Object = GetClassRoot(kJavaLangObject); 973 java_lang_Object->SetObjectSize(sizeof(mirror::Object)); 974 // Allocate in non-movable so that it's possible to check if a JNI weak global ref has been 975 // cleared without triggering the read barrier and unintentionally mark the sentinel alive. 976 runtime->SetSentinel(heap->AllocNonMovableObject<true>( 977 self, java_lang_Object, java_lang_Object->GetObjectSize(), VoidFunctor())); 978 979 // reinit array_iftable_ from any array class instance, they should be == 980 array_iftable_ = GcRoot<mirror::IfTable>(GetClassRoot(kObjectArrayClass)->GetIfTable()); 981 DCHECK_EQ(array_iftable_.Read(), GetClassRoot(kBooleanArrayClass)->GetIfTable()); 982 // String class root was set above 983 mirror::Field::SetClass(GetClassRoot(kJavaLangReflectField)); 984 mirror::Field::SetArrayClass(GetClassRoot(kJavaLangReflectFieldArrayClass)); 985 mirror::Constructor::SetClass(GetClassRoot(kJavaLangReflectConstructor)); 986 mirror::Constructor::SetArrayClass(GetClassRoot(kJavaLangReflectConstructorArrayClass)); 987 mirror::Method::SetClass(GetClassRoot(kJavaLangReflectMethod)); 988 mirror::Method::SetArrayClass(GetClassRoot(kJavaLangReflectMethodArrayClass)); 989 mirror::MethodType::SetClass(GetClassRoot(kJavaLangInvokeMethodType)); 990 mirror::MethodHandleImpl::SetClass(GetClassRoot(kJavaLangInvokeMethodHandleImpl)); 991 mirror::MethodHandlesLookup::SetClass(GetClassRoot(kJavaLangInvokeMethodHandlesLookup)); 992 mirror::CallSite::SetClass(GetClassRoot(kJavaLangInvokeCallSite)); 993 mirror::Reference::SetClass(GetClassRoot(kJavaLangRefReference)); 994 mirror::BooleanArray::SetArrayClass(GetClassRoot(kBooleanArrayClass)); 995 mirror::ByteArray::SetArrayClass(GetClassRoot(kByteArrayClass)); 996 mirror::CharArray::SetArrayClass(GetClassRoot(kCharArrayClass)); 997 mirror::DoubleArray::SetArrayClass(GetClassRoot(kDoubleArrayClass)); 998 mirror::FloatArray::SetArrayClass(GetClassRoot(kFloatArrayClass)); 999 mirror::IntArray::SetArrayClass(GetClassRoot(kIntArrayClass)); 1000 mirror::LongArray::SetArrayClass(GetClassRoot(kLongArrayClass)); 1001 mirror::ShortArray::SetArrayClass(GetClassRoot(kShortArrayClass)); 1002 mirror::Throwable::SetClass(GetClassRoot(kJavaLangThrowable)); 1003 mirror::StackTraceElement::SetClass(GetClassRoot(kJavaLangStackTraceElement)); 1004 mirror::EmulatedStackFrame::SetClass(GetClassRoot(kDalvikSystemEmulatedStackFrame)); 1005 mirror::ClassExt::SetClass(GetClassRoot(kDalvikSystemClassExt)); 1006 1007 for (gc::space::ImageSpace* image_space : spaces) { 1008 // Boot class loader, use a null handle. 1009 std::vector<std::unique_ptr<const DexFile>> dex_files; 1010 if (!AddImageSpace(image_space, 1011 ScopedNullHandle<mirror::ClassLoader>(), 1012 /*dex_elements*/nullptr, 1013 /*dex_location*/nullptr, 1014 /*out*/&dex_files, 1015 error_msg)) { 1016 return false; 1017 } 1018 // Append opened dex files at the end. 1019 boot_dex_files_.insert(boot_dex_files_.end(), 1020 std::make_move_iterator(dex_files.begin()), 1021 std::make_move_iterator(dex_files.end())); 1022 } 1023 for (const std::unique_ptr<const DexFile>& dex_file : boot_dex_files_) { 1024 OatDexFile::MadviseDexFile(*dex_file, MadviseState::kMadviseStateAtLoad); 1025 } 1026 FinishInit(self); 1027 1028 VLOG(startup) << __FUNCTION__ << " exiting"; 1029 return true; 1030 } 1031 1032 bool ClassLinker::IsBootClassLoader(ScopedObjectAccessAlreadyRunnable& soa, 1033 ObjPtr<mirror::ClassLoader> class_loader) { 1034 return class_loader == nullptr || 1035 soa.Decode<mirror::Class>(WellKnownClasses::java_lang_BootClassLoader) == 1036 class_loader->GetClass(); 1037 } 1038 1039 static bool GetDexPathListElementName(ObjPtr<mirror::Object> element, 1040 ObjPtr<mirror::String>* out_name) 1041 REQUIRES_SHARED(Locks::mutator_lock_) { 1042 ArtField* const dex_file_field = 1043 jni::DecodeArtField(WellKnownClasses::dalvik_system_DexPathList__Element_dexFile); 1044 ArtField* const dex_file_name_field = 1045 jni::DecodeArtField(WellKnownClasses::dalvik_system_DexFile_fileName); 1046 DCHECK(dex_file_field != nullptr); 1047 DCHECK(dex_file_name_field != nullptr); 1048 DCHECK(element != nullptr); 1049 CHECK_EQ(dex_file_field->GetDeclaringClass(), element->GetClass()) << element->PrettyTypeOf(); 1050 ObjPtr<mirror::Object> dex_file = dex_file_field->GetObject(element); 1051 if (dex_file == nullptr) { 1052 // Null dex file means it was probably a jar with no dex files, return a null string. 1053 *out_name = nullptr; 1054 return true; 1055 } 1056 ObjPtr<mirror::Object> name_object = dex_file_name_field->GetObject(dex_file); 1057 if (name_object != nullptr) { 1058 *out_name = name_object->AsString(); 1059 return true; 1060 } 1061 return false; 1062 } 1063 1064 static bool FlattenPathClassLoader(ObjPtr<mirror::ClassLoader> class_loader, 1065 std::list<ObjPtr<mirror::String>>* out_dex_file_names, 1066 std::string* error_msg) 1067 REQUIRES_SHARED(Locks::mutator_lock_) { 1068 DCHECK(out_dex_file_names != nullptr); 1069 DCHECK(error_msg != nullptr); 1070 ScopedObjectAccessUnchecked soa(Thread::Current()); 1071 ArtField* const dex_path_list_field = 1072 jni::DecodeArtField(WellKnownClasses::dalvik_system_BaseDexClassLoader_pathList); 1073 ArtField* const dex_elements_field = 1074 jni::DecodeArtField(WellKnownClasses::dalvik_system_DexPathList_dexElements); 1075 CHECK(dex_path_list_field != nullptr); 1076 CHECK(dex_elements_field != nullptr); 1077 while (!ClassLinker::IsBootClassLoader(soa, class_loader)) { 1078 if (soa.Decode<mirror::Class>(WellKnownClasses::dalvik_system_PathClassLoader) != 1079 class_loader->GetClass()) { 1080 *error_msg = StringPrintf("Unknown class loader type %s", 1081 class_loader->PrettyTypeOf().c_str()); 1082 // Unsupported class loader. 1083 return false; 1084 } 1085 ObjPtr<mirror::Object> dex_path_list = dex_path_list_field->GetObject(class_loader); 1086 if (dex_path_list != nullptr) { 1087 // DexPathList has an array dexElements of Elements[] which each contain a dex file. 1088 ObjPtr<mirror::Object> dex_elements_obj = dex_elements_field->GetObject(dex_path_list); 1089 // Loop through each dalvik.system.DexPathList$Element's dalvik.system.DexFile and look 1090 // at the mCookie which is a DexFile vector. 1091 if (dex_elements_obj != nullptr) { 1092 ObjPtr<mirror::ObjectArray<mirror::Object>> dex_elements = 1093 dex_elements_obj->AsObjectArray<mirror::Object>(); 1094 // Reverse order since we insert the parent at the front. 1095 for (int32_t i = dex_elements->GetLength() - 1; i >= 0; --i) { 1096 ObjPtr<mirror::Object> element = dex_elements->GetWithoutChecks(i); 1097 if (element == nullptr) { 1098 *error_msg = StringPrintf("Null dex element at index %d", i); 1099 return false; 1100 } 1101 ObjPtr<mirror::String> name; 1102 if (!GetDexPathListElementName(element, &name)) { 1103 *error_msg = StringPrintf("Invalid dex path list element at index %d", i); 1104 return false; 1105 } 1106 if (name != nullptr) { 1107 out_dex_file_names->push_front(name.Ptr()); 1108 } 1109 } 1110 } 1111 } 1112 class_loader = class_loader->GetParent(); 1113 } 1114 return true; 1115 } 1116 1117 class FixupArtMethodArrayVisitor : public ArtMethodVisitor { 1118 public: 1119 explicit FixupArtMethodArrayVisitor(const ImageHeader& header) : header_(header) {} 1120 1121 virtual void Visit(ArtMethod* method) REQUIRES_SHARED(Locks::mutator_lock_) { 1122 const bool is_copied = method->IsCopied(); 1123 mirror::MethodDexCacheType* resolved_methods = 1124 method->GetDexCacheResolvedMethods(kRuntimePointerSize); 1125 if (resolved_methods != nullptr) { 1126 bool in_image_space = false; 1127 if (kIsDebugBuild || is_copied) { 1128 in_image_space = header_.GetImageSection(ImageHeader::kSectionDexCacheArrays).Contains( 1129 reinterpret_cast<const uint8_t*>(resolved_methods) - header_.GetImageBegin()); 1130 } 1131 // Must be in image space for non-miranda method. 1132 DCHECK(is_copied || in_image_space) 1133 << resolved_methods << " is not in image starting at " 1134 << reinterpret_cast<void*>(header_.GetImageBegin()); 1135 if (!is_copied || in_image_space) { 1136 method->SetDexCacheResolvedMethods(method->GetDexCache()->GetResolvedMethods(), 1137 kRuntimePointerSize); 1138 } 1139 } 1140 } 1141 1142 private: 1143 const ImageHeader& header_; 1144 }; 1145 1146 class VerifyClassInTableArtMethodVisitor : public ArtMethodVisitor { 1147 public: 1148 explicit VerifyClassInTableArtMethodVisitor(ClassTable* table) : table_(table) {} 1149 1150 virtual void Visit(ArtMethod* method) 1151 REQUIRES_SHARED(Locks::mutator_lock_, Locks::classlinker_classes_lock_) { 1152 ObjPtr<mirror::Class> klass = method->GetDeclaringClass(); 1153 if (klass != nullptr && !Runtime::Current()->GetHeap()->ObjectIsInBootImageSpace(klass)) { 1154 CHECK_EQ(table_->LookupByDescriptor(klass), klass) << mirror::Class::PrettyClass(klass); 1155 } 1156 } 1157 1158 private: 1159 ClassTable* const table_; 1160 }; 1161 1162 class VerifyDirectInterfacesInTableClassVisitor { 1163 public: 1164 explicit VerifyDirectInterfacesInTableClassVisitor(ObjPtr<mirror::ClassLoader> class_loader) 1165 : class_loader_(class_loader), self_(Thread::Current()) { } 1166 1167 bool operator()(ObjPtr<mirror::Class> klass) REQUIRES_SHARED(Locks::mutator_lock_) { 1168 if (!klass->IsPrimitive() && klass->GetClassLoader() == class_loader_) { 1169 classes_.push_back(klass); 1170 } 1171 return true; 1172 } 1173 1174 void Check() const REQUIRES_SHARED(Locks::mutator_lock_) { 1175 for (ObjPtr<mirror::Class> klass : classes_) { 1176 for (uint32_t i = 0, num = klass->NumDirectInterfaces(); i != num; ++i) { 1177 CHECK(klass->GetDirectInterface(self_, klass, i) != nullptr) 1178 << klass->PrettyDescriptor() << " iface #" << i; 1179 } 1180 } 1181 } 1182 1183 private: 1184 ObjPtr<mirror::ClassLoader> class_loader_; 1185 Thread* self_; 1186 std::vector<ObjPtr<mirror::Class>> classes_; 1187 }; 1188 1189 class VerifyDeclaringClassVisitor : public ArtMethodVisitor { 1190 public: 1191 VerifyDeclaringClassVisitor() REQUIRES_SHARED(Locks::mutator_lock_, Locks::heap_bitmap_lock_) 1192 : live_bitmap_(Runtime::Current()->GetHeap()->GetLiveBitmap()) {} 1193 1194 virtual void Visit(ArtMethod* method) 1195 REQUIRES_SHARED(Locks::mutator_lock_, Locks::heap_bitmap_lock_) { 1196 ObjPtr<mirror::Class> klass = method->GetDeclaringClassUnchecked(); 1197 if (klass != nullptr) { 1198 CHECK(live_bitmap_->Test(klass.Ptr())) << "Image method has unmarked declaring class"; 1199 } 1200 } 1201 1202 private: 1203 gc::accounting::HeapBitmap* const live_bitmap_; 1204 }; 1205 1206 class FixupInternVisitor { 1207 public: 1208 ALWAYS_INLINE ObjPtr<mirror::Object> TryInsertIntern(mirror::Object* obj) const 1209 REQUIRES_SHARED(Locks::mutator_lock_) { 1210 if (obj != nullptr && obj->IsString()) { 1211 const auto intern = Runtime::Current()->GetInternTable()->InternStrong(obj->AsString()); 1212 return intern; 1213 } 1214 return obj; 1215 } 1216 1217 ALWAYS_INLINE void VisitRootIfNonNull( 1218 mirror::CompressedReference<mirror::Object>* root) const 1219 REQUIRES_SHARED(Locks::mutator_lock_) { 1220 if (!root->IsNull()) { 1221 VisitRoot(root); 1222 } 1223 } 1224 1225 ALWAYS_INLINE void VisitRoot(mirror::CompressedReference<mirror::Object>* root) const 1226 REQUIRES_SHARED(Locks::mutator_lock_) { 1227 root->Assign(TryInsertIntern(root->AsMirrorPtr())); 1228 } 1229 1230 // Visit Class Fields 1231 ALWAYS_INLINE void operator()(ObjPtr<mirror::Object> obj, 1232 MemberOffset offset, 1233 bool is_static ATTRIBUTE_UNUSED) const 1234 REQUIRES_SHARED(Locks::mutator_lock_) { 1235 // There could be overlap between ranges, we must avoid visiting the same reference twice. 1236 // Avoid the class field since we already fixed it up in FixupClassVisitor. 1237 if (offset.Uint32Value() != mirror::Object::ClassOffset().Uint32Value()) { 1238 // Updating images, don't do a read barrier. 1239 // Only string fields are fixed, don't do a verify. 1240 mirror::Object* ref = obj->GetFieldObject<mirror::Object, kVerifyNone, kWithoutReadBarrier>( 1241 offset); 1242 obj->SetFieldObject<false, false>(offset, TryInsertIntern(ref)); 1243 } 1244 } 1245 1246 void operator()(ObjPtr<mirror::Class> klass ATTRIBUTE_UNUSED, 1247 ObjPtr<mirror::Reference> ref) const 1248 REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(Locks::heap_bitmap_lock_) { 1249 this->operator()(ref, mirror::Reference::ReferentOffset(), false); 1250 } 1251 1252 void operator()(mirror::Object* obj) const 1253 REQUIRES_SHARED(Locks::mutator_lock_) { 1254 if (obj->IsDexCache()) { 1255 obj->VisitReferences<true, kVerifyNone, kWithoutReadBarrier>(*this, *this); 1256 } else { 1257 // Don't visit native roots for non-dex-cache 1258 obj->VisitReferences<false, kVerifyNone, kWithoutReadBarrier>(*this, *this); 1259 } 1260 } 1261 }; 1262 1263 // Copies data from one array to another array at the same position 1264 // if pred returns false. If there is a page of continuous data in 1265 // the src array for which pred consistently returns true then 1266 // corresponding page in the dst array will not be touched. 1267 // This should reduce number of allocated physical pages. 1268 template <class T, class NullPred> 1269 static void CopyNonNull(const T* src, size_t count, T* dst, const NullPred& pred) { 1270 for (size_t i = 0; i < count; ++i) { 1271 if (!pred(src[i])) { 1272 dst[i] = src[i]; 1273 } 1274 } 1275 } 1276 1277 template <typename T> 1278 static void CopyDexCachePairs(const std::atomic<mirror::DexCachePair<T>>* src, 1279 size_t count, 1280 std::atomic<mirror::DexCachePair<T>>* dst) { 1281 DCHECK_NE(count, 0u); 1282 DCHECK(!src[0].load(std::memory_order_relaxed).object.IsNull() || 1283 src[0].load(std::memory_order_relaxed).index != 0u); 1284 for (size_t i = 0; i < count; ++i) { 1285 DCHECK_EQ(dst[i].load(std::memory_order_relaxed).index, 0u); 1286 DCHECK(dst[i].load(std::memory_order_relaxed).object.IsNull()); 1287 mirror::DexCachePair<T> source = src[i].load(std::memory_order_relaxed); 1288 if (source.index != 0u || !source.object.IsNull()) { 1289 dst[i].store(source, std::memory_order_relaxed); 1290 } 1291 } 1292 } 1293 1294 template <typename T> 1295 static void CopyNativeDexCachePairs(std::atomic<mirror::NativeDexCachePair<T>>* src, 1296 size_t count, 1297 std::atomic<mirror::NativeDexCachePair<T>>* dst, 1298 PointerSize pointer_size) { 1299 DCHECK_NE(count, 0u); 1300 DCHECK(mirror::DexCache::GetNativePairPtrSize(src, 0, pointer_size).object != nullptr || 1301 mirror::DexCache::GetNativePairPtrSize(src, 0, pointer_size).index != 0u); 1302 for (size_t i = 0; i < count; ++i) { 1303 DCHECK_EQ(mirror::DexCache::GetNativePairPtrSize(dst, i, pointer_size).index, 0u); 1304 DCHECK(mirror::DexCache::GetNativePairPtrSize(dst, i, pointer_size).object == nullptr); 1305 mirror::NativeDexCachePair<T> source = 1306 mirror::DexCache::GetNativePairPtrSize(src, i, pointer_size); 1307 if (source.index != 0u || source.object != nullptr) { 1308 mirror::DexCache::SetNativePairPtrSize(dst, i, source, pointer_size); 1309 } 1310 } 1311 } 1312 1313 // new_class_set is the set of classes that were read from the class table section in the image. 1314 // If there was no class table section, it is null. 1315 // Note: using a class here to avoid having to make ClassLinker internals public. 1316 class AppImageClassLoadersAndDexCachesHelper { 1317 public: 1318 static bool Update( 1319 ClassLinker* class_linker, 1320 gc::space::ImageSpace* space, 1321 Handle<mirror::ClassLoader> class_loader, 1322 Handle<mirror::ObjectArray<mirror::DexCache>> dex_caches, 1323 ClassTable::ClassSet* new_class_set, 1324 bool* out_forward_dex_cache_array, 1325 std::string* out_error_msg) 1326 REQUIRES(!Locks::dex_lock_) 1327 REQUIRES_SHARED(Locks::mutator_lock_); 1328 }; 1329 1330 bool AppImageClassLoadersAndDexCachesHelper::Update( 1331 ClassLinker* class_linker, 1332 gc::space::ImageSpace* space, 1333 Handle<mirror::ClassLoader> class_loader, 1334 Handle<mirror::ObjectArray<mirror::DexCache>> dex_caches, 1335 ClassTable::ClassSet* new_class_set, 1336 bool* out_forward_dex_cache_array, 1337 std::string* out_error_msg) 1338 REQUIRES(!Locks::dex_lock_) 1339 REQUIRES_SHARED(Locks::mutator_lock_) { 1340 DCHECK(out_forward_dex_cache_array != nullptr); 1341 DCHECK(out_error_msg != nullptr); 1342 PointerSize image_pointer_size = class_linker->GetImagePointerSize(); 1343 Thread* const self = Thread::Current(); 1344 gc::Heap* const heap = Runtime::Current()->GetHeap(); 1345 const ImageHeader& header = space->GetImageHeader(); 1346 { 1347 // Add image classes into the class table for the class loader, and fixup the dex caches and 1348 // class loader fields. 1349 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_); 1350 // Dex cache array fixup is all or nothing, we must reject app images that have mixed since we 1351 // rely on clobering the dex cache arrays in the image to forward to bss. 1352 size_t num_dex_caches_with_bss_arrays = 0; 1353 const size_t num_dex_caches = dex_caches->GetLength(); 1354 for (size_t i = 0; i < num_dex_caches; i++) { 1355 ObjPtr<mirror::DexCache> const dex_cache = dex_caches->Get(i); 1356 const DexFile* const dex_file = dex_cache->GetDexFile(); 1357 const OatFile::OatDexFile* oat_dex_file = dex_file->GetOatDexFile(); 1358 if (oat_dex_file != nullptr && oat_dex_file->GetDexCacheArrays() != nullptr) { 1359 ++num_dex_caches_with_bss_arrays; 1360 } 1361 } 1362 *out_forward_dex_cache_array = num_dex_caches_with_bss_arrays != 0; 1363 if (*out_forward_dex_cache_array) { 1364 if (num_dex_caches_with_bss_arrays != num_dex_caches) { 1365 // Reject application image since we cannot forward only some of the dex cache arrays. 1366 // TODO: We could get around this by having a dedicated forwarding slot. It should be an 1367 // uncommon case. 1368 *out_error_msg = StringPrintf("Dex caches in bss does not match total: %zu vs %zu", 1369 num_dex_caches_with_bss_arrays, 1370 num_dex_caches); 1371 return false; 1372 } 1373 } 1374 1375 // Only add the classes to the class loader after the points where we can return false. 1376 for (size_t i = 0; i < num_dex_caches; i++) { 1377 ObjPtr<mirror::DexCache> dex_cache = dex_caches->Get(i); 1378 const DexFile* const dex_file = dex_cache->GetDexFile(); 1379 const OatFile::OatDexFile* oat_dex_file = dex_file->GetOatDexFile(); 1380 if (oat_dex_file != nullptr && oat_dex_file->GetDexCacheArrays() != nullptr) { 1381 // If the oat file expects the dex cache arrays to be in the BSS, then allocate there and 1382 // copy over the arrays. 1383 DCHECK(dex_file != nullptr); 1384 size_t num_strings = mirror::DexCache::kDexCacheStringCacheSize; 1385 if (dex_file->NumStringIds() < num_strings) { 1386 num_strings = dex_file->NumStringIds(); 1387 } 1388 size_t num_types = mirror::DexCache::kDexCacheTypeCacheSize; 1389 if (dex_file->NumTypeIds() < num_types) { 1390 num_types = dex_file->NumTypeIds(); 1391 } 1392 size_t num_methods = mirror::DexCache::kDexCacheMethodCacheSize; 1393 if (dex_file->NumMethodIds() < num_methods) { 1394 num_methods = dex_file->NumMethodIds(); 1395 } 1396 size_t num_fields = mirror::DexCache::kDexCacheFieldCacheSize; 1397 if (dex_file->NumFieldIds() < num_fields) { 1398 num_fields = dex_file->NumFieldIds(); 1399 } 1400 size_t num_method_types = mirror::DexCache::kDexCacheMethodTypeCacheSize; 1401 if (dex_file->NumProtoIds() < num_method_types) { 1402 num_method_types = dex_file->NumProtoIds(); 1403 } 1404 const size_t num_call_sites = dex_file->NumCallSiteIds(); 1405 CHECK_EQ(num_strings, dex_cache->NumStrings()); 1406 CHECK_EQ(num_types, dex_cache->NumResolvedTypes()); 1407 CHECK_EQ(num_methods, dex_cache->NumResolvedMethods()); 1408 CHECK_EQ(num_fields, dex_cache->NumResolvedFields()); 1409 CHECK_EQ(num_method_types, dex_cache->NumResolvedMethodTypes()); 1410 CHECK_EQ(num_call_sites, dex_cache->NumResolvedCallSites()); 1411 DexCacheArraysLayout layout(image_pointer_size, dex_file); 1412 uint8_t* const raw_arrays = oat_dex_file->GetDexCacheArrays(); 1413 if (num_strings != 0u) { 1414 mirror::StringDexCacheType* const image_resolved_strings = dex_cache->GetStrings(); 1415 mirror::StringDexCacheType* const strings = 1416 reinterpret_cast<mirror::StringDexCacheType*>(raw_arrays + layout.StringsOffset()); 1417 CopyDexCachePairs(image_resolved_strings, num_strings, strings); 1418 dex_cache->SetStrings(strings); 1419 } 1420 if (num_types != 0u) { 1421 mirror::TypeDexCacheType* const image_resolved_types = dex_cache->GetResolvedTypes(); 1422 mirror::TypeDexCacheType* const types = 1423 reinterpret_cast<mirror::TypeDexCacheType*>(raw_arrays + layout.TypesOffset()); 1424 CopyDexCachePairs(image_resolved_types, num_types, types); 1425 dex_cache->SetResolvedTypes(types); 1426 } 1427 if (num_methods != 0u) { 1428 mirror::MethodDexCacheType* const image_resolved_methods = 1429 dex_cache->GetResolvedMethods(); 1430 mirror::MethodDexCacheType* const methods = 1431 reinterpret_cast<mirror::MethodDexCacheType*>(raw_arrays + layout.MethodsOffset()); 1432 CopyNativeDexCachePairs(image_resolved_methods, num_methods, methods, image_pointer_size); 1433 dex_cache->SetResolvedMethods(methods); 1434 } 1435 if (num_fields != 0u) { 1436 mirror::FieldDexCacheType* const image_resolved_fields = dex_cache->GetResolvedFields(); 1437 mirror::FieldDexCacheType* const fields = 1438 reinterpret_cast<mirror::FieldDexCacheType*>(raw_arrays + layout.FieldsOffset()); 1439 CopyNativeDexCachePairs(image_resolved_fields, num_fields, fields, image_pointer_size); 1440 dex_cache->SetResolvedFields(fields); 1441 } 1442 if (num_method_types != 0u) { 1443 // NOTE: We currently (Sep 2016) do not resolve any method types at 1444 // compile time, but plan to in the future. This code exists for the 1445 // sake of completeness. 1446 mirror::MethodTypeDexCacheType* const image_resolved_method_types = 1447 dex_cache->GetResolvedMethodTypes(); 1448 mirror::MethodTypeDexCacheType* const method_types = 1449 reinterpret_cast<mirror::MethodTypeDexCacheType*>( 1450 raw_arrays + layout.MethodTypesOffset()); 1451 CopyDexCachePairs(image_resolved_method_types, num_method_types, method_types); 1452 dex_cache->SetResolvedMethodTypes(method_types); 1453 } 1454 if (num_call_sites != 0u) { 1455 GcRoot<mirror::CallSite>* const image_resolved_call_sites = 1456 dex_cache->GetResolvedCallSites(); 1457 GcRoot<mirror::CallSite>* const call_sites = 1458 reinterpret_cast<GcRoot<mirror::CallSite>*>(raw_arrays + layout.CallSitesOffset()); 1459 for (size_t j = 0; kIsDebugBuild && j < num_call_sites; ++j) { 1460 DCHECK(call_sites[j].IsNull()); 1461 } 1462 CopyNonNull(image_resolved_call_sites, 1463 num_call_sites, 1464 call_sites, 1465 [](const GcRoot<mirror::CallSite>& elem) { 1466 return elem.IsNull(); 1467 }); 1468 dex_cache->SetResolvedCallSites(call_sites); 1469 } 1470 } 1471 { 1472 WriterMutexLock mu2(self, *Locks::dex_lock_); 1473 // Make sure to do this after we update the arrays since we store the resolved types array 1474 // in DexCacheData in RegisterDexFileLocked. We need the array pointer to be the one in the 1475 // BSS. 1476 CHECK(!class_linker->FindDexCacheDataLocked(*dex_file).IsValid()); 1477 class_linker->RegisterDexFileLocked(*dex_file, dex_cache, class_loader.Get()); 1478 } 1479 if (kIsDebugBuild) { 1480 CHECK(new_class_set != nullptr); 1481 mirror::TypeDexCacheType* const types = dex_cache->GetResolvedTypes(); 1482 const size_t num_types = dex_cache->NumResolvedTypes(); 1483 for (size_t j = 0; j != num_types; ++j) { 1484 // The image space is not yet added to the heap, avoid read barriers. 1485 ObjPtr<mirror::Class> klass = types[j].load(std::memory_order_relaxed).object.Read(); 1486 if (space->HasAddress(klass.Ptr())) { 1487 DCHECK(!klass->IsErroneous()) << klass->GetStatus(); 1488 auto it = new_class_set->Find(ClassTable::TableSlot(klass)); 1489 DCHECK(it != new_class_set->end()); 1490 DCHECK_EQ(it->Read(), klass); 1491 ObjPtr<mirror::Class> super_class = klass->GetSuperClass(); 1492 if (super_class != nullptr && !heap->ObjectIsInBootImageSpace(super_class)) { 1493 auto it2 = new_class_set->Find(ClassTable::TableSlot(super_class)); 1494 DCHECK(it2 != new_class_set->end()); 1495 DCHECK_EQ(it2->Read(), super_class); 1496 } 1497 for (ArtMethod& m : klass->GetDirectMethods(kRuntimePointerSize)) { 1498 const void* code = m.GetEntryPointFromQuickCompiledCode(); 1499 const void* oat_code = m.IsInvokable() ? class_linker->GetQuickOatCodeFor(&m) : code; 1500 if (!class_linker->IsQuickResolutionStub(code) && 1501 !class_linker->IsQuickGenericJniStub(code) && 1502 !class_linker->IsQuickToInterpreterBridge(code) && 1503 !m.IsNative()) { 1504 DCHECK_EQ(code, oat_code) << m.PrettyMethod(); 1505 } 1506 } 1507 for (ArtMethod& m : klass->GetVirtualMethods(kRuntimePointerSize)) { 1508 const void* code = m.GetEntryPointFromQuickCompiledCode(); 1509 const void* oat_code = m.IsInvokable() ? class_linker->GetQuickOatCodeFor(&m) : code; 1510 if (!class_linker->IsQuickResolutionStub(code) && 1511 !class_linker->IsQuickGenericJniStub(code) && 1512 !class_linker->IsQuickToInterpreterBridge(code) && 1513 !m.IsNative()) { 1514 DCHECK_EQ(code, oat_code) << m.PrettyMethod(); 1515 } 1516 } 1517 } 1518 } 1519 } 1520 } 1521 } 1522 { 1523 // Fixup all the literal strings happens at app images which are supposed to be interned. 1524 ScopedTrace timing("Fixup String Intern in image and dex_cache"); 1525 const auto& image_header = space->GetImageHeader(); 1526 const auto bitmap = space->GetMarkBitmap(); // bitmap of objects 1527 const uint8_t* target_base = space->GetMemMap()->Begin(); 1528 const ImageSection& objects_section = 1529 image_header.GetImageSection(ImageHeader::kSectionObjects); 1530 1531 uintptr_t objects_begin = reinterpret_cast<uintptr_t>(target_base + objects_section.Offset()); 1532 uintptr_t objects_end = reinterpret_cast<uintptr_t>(target_base + objects_section.End()); 1533 1534 FixupInternVisitor fixup_intern_visitor; 1535 bitmap->VisitMarkedRange(objects_begin, objects_end, fixup_intern_visitor); 1536 } 1537 if (*out_forward_dex_cache_array) { 1538 ScopedTrace timing("Fixup ArtMethod dex cache arrays"); 1539 FixupArtMethodArrayVisitor visitor(header); 1540 header.VisitPackedArtMethods(&visitor, space->Begin(), kRuntimePointerSize); 1541 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(class_loader.Get()); 1542 } 1543 if (kVerifyArtMethodDeclaringClasses) { 1544 ScopedTrace timing("Verify declaring classes"); 1545 ReaderMutexLock rmu(self, *Locks::heap_bitmap_lock_); 1546 VerifyDeclaringClassVisitor visitor; 1547 header.VisitPackedArtMethods(&visitor, space->Begin(), kRuntimePointerSize); 1548 } 1549 return true; 1550 } 1551 1552 // Update the class loader. Should only be used on classes in the image space. 1553 class UpdateClassLoaderVisitor { 1554 public: 1555 UpdateClassLoaderVisitor(gc::space::ImageSpace* space, ObjPtr<mirror::ClassLoader> class_loader) 1556 : space_(space), 1557 class_loader_(class_loader) {} 1558 1559 bool operator()(ObjPtr<mirror::Class> klass) const REQUIRES_SHARED(Locks::mutator_lock_) { 1560 // Do not update class loader for boot image classes where the app image 1561 // class loader is only the initiating loader but not the defining loader. 1562 if (klass->GetClassLoader() != nullptr) { 1563 klass->SetClassLoader(class_loader_); 1564 } 1565 return true; 1566 } 1567 1568 gc::space::ImageSpace* const space_; 1569 ObjPtr<mirror::ClassLoader> const class_loader_; 1570 }; 1571 1572 static std::unique_ptr<const DexFile> OpenOatDexFile(const OatFile* oat_file, 1573 const char* location, 1574 std::string* error_msg) 1575 REQUIRES_SHARED(Locks::mutator_lock_) { 1576 DCHECK(error_msg != nullptr); 1577 std::unique_ptr<const DexFile> dex_file; 1578 const OatFile::OatDexFile* oat_dex_file = oat_file->GetOatDexFile(location, nullptr, error_msg); 1579 if (oat_dex_file == nullptr) { 1580 return std::unique_ptr<const DexFile>(); 1581 } 1582 std::string inner_error_msg; 1583 dex_file = oat_dex_file->OpenDexFile(&inner_error_msg); 1584 if (dex_file == nullptr) { 1585 *error_msg = StringPrintf("Failed to open dex file %s from within oat file %s error '%s'", 1586 location, 1587 oat_file->GetLocation().c_str(), 1588 inner_error_msg.c_str()); 1589 return std::unique_ptr<const DexFile>(); 1590 } 1591 1592 if (dex_file->GetLocationChecksum() != oat_dex_file->GetDexFileLocationChecksum()) { 1593 *error_msg = StringPrintf("Checksums do not match for %s: %x vs %x", 1594 location, 1595 dex_file->GetLocationChecksum(), 1596 oat_dex_file->GetDexFileLocationChecksum()); 1597 return std::unique_ptr<const DexFile>(); 1598 } 1599 return dex_file; 1600 } 1601 1602 bool ClassLinker::OpenImageDexFiles(gc::space::ImageSpace* space, 1603 std::vector<std::unique_ptr<const DexFile>>* out_dex_files, 1604 std::string* error_msg) { 1605 ScopedAssertNoThreadSuspension nts(__FUNCTION__); 1606 const ImageHeader& header = space->GetImageHeader(); 1607 ObjPtr<mirror::Object> dex_caches_object = header.GetImageRoot(ImageHeader::kDexCaches); 1608 DCHECK(dex_caches_object != nullptr); 1609 mirror::ObjectArray<mirror::DexCache>* dex_caches = 1610 dex_caches_object->AsObjectArray<mirror::DexCache>(); 1611 const OatFile* oat_file = space->GetOatFile(); 1612 for (int32_t i = 0; i < dex_caches->GetLength(); i++) { 1613 ObjPtr<mirror::DexCache> dex_cache = dex_caches->Get(i); 1614 std::string dex_file_location(dex_cache->GetLocation()->ToModifiedUtf8()); 1615 std::unique_ptr<const DexFile> dex_file = OpenOatDexFile(oat_file, 1616 dex_file_location.c_str(), 1617 error_msg); 1618 if (dex_file == nullptr) { 1619 return false; 1620 } 1621 dex_cache->SetDexFile(dex_file.get()); 1622 out_dex_files->push_back(std::move(dex_file)); 1623 } 1624 return true; 1625 } 1626 1627 // Helper class for ArtMethod checks when adding an image. Keeps all required functionality 1628 // together and caches some intermediate results. 1629 class ImageSanityChecks FINAL { 1630 public: 1631 static void CheckObjects(gc::Heap* heap, ClassLinker* class_linker) 1632 REQUIRES_SHARED(Locks::mutator_lock_) { 1633 ImageSanityChecks isc(heap, class_linker); 1634 auto visitor = [&](mirror::Object* obj) REQUIRES_SHARED(Locks::mutator_lock_) { 1635 DCHECK(obj != nullptr); 1636 CHECK(obj->GetClass() != nullptr) << "Null class in object " << obj; 1637 CHECK(obj->GetClass()->GetClass() != nullptr) << "Null class class " << obj; 1638 if (obj->IsClass()) { 1639 auto klass = obj->AsClass(); 1640 for (ArtField& field : klass->GetIFields()) { 1641 CHECK_EQ(field.GetDeclaringClass(), klass); 1642 } 1643 for (ArtField& field : klass->GetSFields()) { 1644 CHECK_EQ(field.GetDeclaringClass(), klass); 1645 } 1646 const auto pointer_size = isc.pointer_size_; 1647 for (auto& m : klass->GetMethods(pointer_size)) { 1648 isc.SanityCheckArtMethod(&m, klass); 1649 } 1650 auto* vtable = klass->GetVTable(); 1651 if (vtable != nullptr) { 1652 isc.SanityCheckArtMethodPointerArray(vtable, nullptr); 1653 } 1654 if (klass->ShouldHaveImt()) { 1655 ImTable* imt = klass->GetImt(pointer_size); 1656 for (size_t i = 0; i < ImTable::kSize; ++i) { 1657 isc.SanityCheckArtMethod(imt->Get(i, pointer_size), nullptr); 1658 } 1659 } 1660 if (klass->ShouldHaveEmbeddedVTable()) { 1661 for (int32_t i = 0; i < klass->GetEmbeddedVTableLength(); ++i) { 1662 isc.SanityCheckArtMethod(klass->GetEmbeddedVTableEntry(i, pointer_size), nullptr); 1663 } 1664 } 1665 mirror::IfTable* iftable = klass->GetIfTable(); 1666 for (int32_t i = 0; i < klass->GetIfTableCount(); ++i) { 1667 if (iftable->GetMethodArrayCount(i) > 0) { 1668 isc.SanityCheckArtMethodPointerArray(iftable->GetMethodArray(i), nullptr); 1669 } 1670 } 1671 } 1672 }; 1673 heap->VisitObjects(visitor); 1674 } 1675 1676 static void CheckArtMethodDexCacheArray(gc::Heap* heap, 1677 ClassLinker* class_linker, 1678 mirror::MethodDexCacheType* arr, 1679 size_t size) 1680 REQUIRES_SHARED(Locks::mutator_lock_) { 1681 ImageSanityChecks isc(heap, class_linker); 1682 isc.SanityCheckArtMethodDexCacheArray(arr, size); 1683 } 1684 1685 private: 1686 ImageSanityChecks(gc::Heap* heap, ClassLinker* class_linker) 1687 : spaces_(heap->GetBootImageSpaces()), 1688 pointer_size_(class_linker->GetImagePointerSize()) { 1689 space_begin_.reserve(spaces_.size()); 1690 method_sections_.reserve(spaces_.size()); 1691 runtime_method_sections_.reserve(spaces_.size()); 1692 for (gc::space::ImageSpace* space : spaces_) { 1693 space_begin_.push_back(space->Begin()); 1694 auto& header = space->GetImageHeader(); 1695 method_sections_.push_back(&header.GetMethodsSection()); 1696 runtime_method_sections_.push_back(&header.GetRuntimeMethodsSection()); 1697 } 1698 } 1699 1700 void SanityCheckArtMethod(ArtMethod* m, ObjPtr<mirror::Class> expected_class) 1701 REQUIRES_SHARED(Locks::mutator_lock_) { 1702 if (m->IsRuntimeMethod()) { 1703 ObjPtr<mirror::Class> declaring_class = m->GetDeclaringClassUnchecked(); 1704 CHECK(declaring_class == nullptr) << declaring_class << " " << m->PrettyMethod(); 1705 } else if (m->IsCopied()) { 1706 CHECK(m->GetDeclaringClass() != nullptr) << m->PrettyMethod(); 1707 } else if (expected_class != nullptr) { 1708 CHECK_EQ(m->GetDeclaringClassUnchecked(), expected_class) << m->PrettyMethod(); 1709 } 1710 if (!spaces_.empty()) { 1711 bool contains = false; 1712 for (size_t i = 0; !contains && i != space_begin_.size(); ++i) { 1713 const size_t offset = reinterpret_cast<uint8_t*>(m) - space_begin_[i]; 1714 contains = method_sections_[i]->Contains(offset) || 1715 runtime_method_sections_[i]->Contains(offset); 1716 } 1717 CHECK(contains) << m << " not found"; 1718 } 1719 } 1720 1721 void SanityCheckArtMethodPointerArray(ObjPtr<mirror::PointerArray> arr, 1722 ObjPtr<mirror::Class> expected_class) 1723 REQUIRES_SHARED(Locks::mutator_lock_) { 1724 CHECK(arr != nullptr); 1725 for (int32_t j = 0; j < arr->GetLength(); ++j) { 1726 auto* method = arr->GetElementPtrSize<ArtMethod*>(j, pointer_size_); 1727 // expected_class == null means we are a dex cache. 1728 if (expected_class != nullptr) { 1729 CHECK(method != nullptr); 1730 } 1731 if (method != nullptr) { 1732 SanityCheckArtMethod(method, expected_class); 1733 } 1734 } 1735 } 1736 1737 void SanityCheckArtMethodDexCacheArray(mirror::MethodDexCacheType* arr, size_t size) 1738 REQUIRES_SHARED(Locks::mutator_lock_) { 1739 CHECK_EQ(arr != nullptr, size != 0u); 1740 if (arr != nullptr) { 1741 bool contains = false; 1742 for (auto space : spaces_) { 1743 auto offset = reinterpret_cast<uint8_t*>(arr) - space->Begin(); 1744 if (space->GetImageHeader().GetImageSection( 1745 ImageHeader::kSectionDexCacheArrays).Contains(offset)) { 1746 contains = true; 1747 break; 1748 } 1749 } 1750 CHECK(contains); 1751 } 1752 for (size_t j = 0; j < size; ++j) { 1753 auto pair = mirror::DexCache::GetNativePairPtrSize(arr, j, pointer_size_); 1754 ArtMethod* method = pair.object; 1755 // expected_class == null means we are a dex cache. 1756 if (method != nullptr) { 1757 SanityCheckArtMethod(method, nullptr); 1758 } 1759 } 1760 } 1761 1762 const std::vector<gc::space::ImageSpace*>& spaces_; 1763 const PointerSize pointer_size_; 1764 1765 // Cached sections from the spaces. 1766 std::vector<const uint8_t*> space_begin_; 1767 std::vector<const ImageSection*> method_sections_; 1768 std::vector<const ImageSection*> runtime_method_sections_; 1769 }; 1770 1771 bool ClassLinker::AddImageSpace( 1772 gc::space::ImageSpace* space, 1773 Handle<mirror::ClassLoader> class_loader, 1774 jobjectArray dex_elements, 1775 const char* dex_location, 1776 std::vector<std::unique_ptr<const DexFile>>* out_dex_files, 1777 std::string* error_msg) { 1778 DCHECK(out_dex_files != nullptr); 1779 DCHECK(error_msg != nullptr); 1780 const uint64_t start_time = NanoTime(); 1781 const bool app_image = class_loader != nullptr; 1782 const ImageHeader& header = space->GetImageHeader(); 1783 ObjPtr<mirror::Object> dex_caches_object = header.GetImageRoot(ImageHeader::kDexCaches); 1784 DCHECK(dex_caches_object != nullptr); 1785 Runtime* const runtime = Runtime::Current(); 1786 gc::Heap* const heap = runtime->GetHeap(); 1787 Thread* const self = Thread::Current(); 1788 // Check that the image is what we are expecting. 1789 if (image_pointer_size_ != space->GetImageHeader().GetPointerSize()) { 1790 *error_msg = StringPrintf("Application image pointer size does not match runtime: %zu vs %zu", 1791 static_cast<size_t>(space->GetImageHeader().GetPointerSize()), 1792 image_pointer_size_); 1793 return false; 1794 } 1795 size_t expected_image_roots = ImageHeader::NumberOfImageRoots(app_image); 1796 if (static_cast<size_t>(header.GetImageRoots()->GetLength()) != expected_image_roots) { 1797 *error_msg = StringPrintf("Expected %zu image roots but got %d", 1798 expected_image_roots, 1799 header.GetImageRoots()->GetLength()); 1800 return false; 1801 } 1802 StackHandleScope<3> hs(self); 1803 Handle<mirror::ObjectArray<mirror::DexCache>> dex_caches( 1804 hs.NewHandle(dex_caches_object->AsObjectArray<mirror::DexCache>())); 1805 Handle<mirror::ObjectArray<mirror::Class>> class_roots(hs.NewHandle( 1806 header.GetImageRoot(ImageHeader::kClassRoots)->AsObjectArray<mirror::Class>())); 1807 static_assert(ImageHeader::kClassLoader + 1u == ImageHeader::kImageRootsMax, 1808 "Class loader should be the last image root."); 1809 MutableHandle<mirror::ClassLoader> image_class_loader(hs.NewHandle( 1810 app_image ? header.GetImageRoot(ImageHeader::kClassLoader)->AsClassLoader() : nullptr)); 1811 DCHECK(class_roots != nullptr); 1812 if (class_roots->GetLength() != static_cast<int32_t>(kClassRootsMax)) { 1813 *error_msg = StringPrintf("Expected %d class roots but got %d", 1814 class_roots->GetLength(), 1815 static_cast<int32_t>(kClassRootsMax)); 1816 return false; 1817 } 1818 // Check against existing class roots to make sure they match the ones in the boot image. 1819 for (size_t i = 0; i < kClassRootsMax; i++) { 1820 if (class_roots->Get(i) != GetClassRoot(static_cast<ClassRoot>(i))) { 1821 *error_msg = "App image class roots must have pointer equality with runtime ones."; 1822 return false; 1823 } 1824 } 1825 const OatFile* oat_file = space->GetOatFile(); 1826 if (oat_file->GetOatHeader().GetDexFileCount() != 1827 static_cast<uint32_t>(dex_caches->GetLength())) { 1828 *error_msg = "Dex cache count and dex file count mismatch while trying to initialize from " 1829 "image"; 1830 return false; 1831 } 1832 1833 for (int32_t i = 0; i < dex_caches->GetLength(); i++) { 1834 ObjPtr<mirror::DexCache> dex_cache = dex_caches->Get(i); 1835 std::string dex_file_location(dex_cache->GetLocation()->ToModifiedUtf8()); 1836 // TODO: Only store qualified paths. 1837 // If non qualified, qualify it. 1838 if (dex_file_location.find('/') == std::string::npos) { 1839 std::string dex_location_path = dex_location; 1840 const size_t pos = dex_location_path.find_last_of('/'); 1841 CHECK_NE(pos, std::string::npos); 1842 dex_location_path = dex_location_path.substr(0, pos + 1); // Keep trailing '/' 1843 dex_file_location = dex_location_path + dex_file_location; 1844 } 1845 std::unique_ptr<const DexFile> dex_file = OpenOatDexFile(oat_file, 1846 dex_file_location.c_str(), 1847 error_msg); 1848 if (dex_file == nullptr) { 1849 return false; 1850 } 1851 1852 if (app_image) { 1853 // The current dex file field is bogus, overwrite it so that we can get the dex file in the 1854 // loop below. 1855 dex_cache->SetDexFile(dex_file.get()); 1856 mirror::TypeDexCacheType* const types = dex_cache->GetResolvedTypes(); 1857 for (int32_t j = 0, num_types = dex_cache->NumResolvedTypes(); j < num_types; j++) { 1858 ObjPtr<mirror::Class> klass = types[j].load(std::memory_order_relaxed).object.Read(); 1859 if (klass != nullptr) { 1860 DCHECK(!klass->IsErroneous()) << klass->GetStatus(); 1861 } 1862 } 1863 } else { 1864 if (kSanityCheckObjects) { 1865 ImageSanityChecks::CheckArtMethodDexCacheArray(heap, 1866 this, 1867 dex_cache->GetResolvedMethods(), 1868 dex_cache->NumResolvedMethods()); 1869 } 1870 // Register dex files, keep track of existing ones that are conflicts. 1871 AppendToBootClassPath(*dex_file.get(), dex_cache); 1872 } 1873 out_dex_files->push_back(std::move(dex_file)); 1874 } 1875 1876 if (app_image) { 1877 ScopedObjectAccessUnchecked soa(Thread::Current()); 1878 // Check that the class loader resolves the same way as the ones in the image. 1879 // Image class loader [A][B][C][image dex files] 1880 // Class loader = [???][dex_elements][image dex files] 1881 // Need to ensure that [???][dex_elements] == [A][B][C]. 1882 // For each class loader, PathClassLoader, the laoder checks the parent first. Also the logic 1883 // for PathClassLoader does this by looping through the array of dex files. To ensure they 1884 // resolve the same way, simply flatten the hierarchy in the way the resolution order would be, 1885 // and check that the dex file names are the same. 1886 if (IsBootClassLoader(soa, image_class_loader.Get())) { 1887 *error_msg = "Unexpected BootClassLoader in app image"; 1888 return false; 1889 } 1890 std::list<ObjPtr<mirror::String>> image_dex_file_names; 1891 std::string temp_error_msg; 1892 if (!FlattenPathClassLoader(image_class_loader.Get(), &image_dex_file_names, &temp_error_msg)) { 1893 *error_msg = StringPrintf("Failed to flatten image class loader hierarchy '%s'", 1894 temp_error_msg.c_str()); 1895 return false; 1896 } 1897 std::list<ObjPtr<mirror::String>> loader_dex_file_names; 1898 if (!FlattenPathClassLoader(class_loader.Get(), &loader_dex_file_names, &temp_error_msg)) { 1899 *error_msg = StringPrintf("Failed to flatten class loader hierarchy '%s'", 1900 temp_error_msg.c_str()); 1901 return false; 1902 } 1903 // Add the temporary dex path list elements at the end. 1904 auto elements = soa.Decode<mirror::ObjectArray<mirror::Object>>(dex_elements); 1905 for (size_t i = 0, num_elems = elements->GetLength(); i < num_elems; ++i) { 1906 ObjPtr<mirror::Object> element = elements->GetWithoutChecks(i); 1907 if (element != nullptr) { 1908 // If we are somewhere in the middle of the array, there may be nulls at the end. 1909 ObjPtr<mirror::String> name; 1910 if (GetDexPathListElementName(element, &name) && name != nullptr) { 1911 loader_dex_file_names.push_back(name); 1912 } 1913 } 1914 } 1915 // Ignore the number of image dex files since we are adding those to the class loader anyways. 1916 CHECK_GE(static_cast<size_t>(image_dex_file_names.size()), 1917 static_cast<size_t>(dex_caches->GetLength())); 1918 size_t image_count = image_dex_file_names.size() - dex_caches->GetLength(); 1919 // Check that the dex file names match. 1920 bool equal = image_count == loader_dex_file_names.size(); 1921 if (equal) { 1922 auto it1 = image_dex_file_names.begin(); 1923 auto it2 = loader_dex_file_names.begin(); 1924 for (size_t i = 0; equal && i < image_count; ++i, ++it1, ++it2) { 1925 equal = equal && (*it1)->Equals(*it2); 1926 } 1927 } 1928 if (!equal) { 1929 VLOG(image) << "Image dex files " << image_dex_file_names.size(); 1930 for (ObjPtr<mirror::String> name : image_dex_file_names) { 1931 VLOG(image) << name->ToModifiedUtf8(); 1932 } 1933 VLOG(image) << "Loader dex files " << loader_dex_file_names.size(); 1934 for (ObjPtr<mirror::String> name : loader_dex_file_names) { 1935 VLOG(image) << name->ToModifiedUtf8(); 1936 } 1937 *error_msg = "Rejecting application image due to class loader mismatch"; 1938 // Ignore class loader mismatch for now since these would just use possibly incorrect 1939 // oat code anyways. The structural class check should be done in the parent. 1940 } 1941 } 1942 1943 if (kSanityCheckObjects) { 1944 for (int32_t i = 0; i < dex_caches->GetLength(); i++) { 1945 auto* dex_cache = dex_caches->Get(i); 1946 for (size_t j = 0; j < dex_cache->NumResolvedFields(); ++j) { 1947 auto* field = dex_cache->GetResolvedField(j, image_pointer_size_); 1948 if (field != nullptr) { 1949 CHECK(field->GetDeclaringClass()->GetClass() != nullptr); 1950 } 1951 } 1952 } 1953 if (!app_image) { 1954 ImageSanityChecks::CheckObjects(heap, this); 1955 } 1956 } 1957 1958 // Set entry point to interpreter if in InterpretOnly mode. 1959 if (!runtime->IsAotCompiler() && runtime->GetInstrumentation()->InterpretOnly()) { 1960 SetInterpreterEntrypointArtMethodVisitor visitor(image_pointer_size_); 1961 header.VisitPackedArtMethods(&visitor, space->Begin(), image_pointer_size_); 1962 } 1963 1964 ClassTable* class_table = nullptr; 1965 { 1966 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_); 1967 class_table = InsertClassTableForClassLoader(class_loader.Get()); 1968 } 1969 // If we have a class table section, read it and use it for verification in 1970 // UpdateAppImageClassLoadersAndDexCaches. 1971 ClassTable::ClassSet temp_set; 1972 const ImageSection& class_table_section = header.GetImageSection(ImageHeader::kSectionClassTable); 1973 const bool added_class_table = class_table_section.Size() > 0u; 1974 if (added_class_table) { 1975 const uint64_t start_time2 = NanoTime(); 1976 size_t read_count = 0; 1977 temp_set = ClassTable::ClassSet(space->Begin() + class_table_section.Offset(), 1978 /*make copy*/false, 1979 &read_count); 1980 VLOG(image) << "Adding class table classes took " << PrettyDuration(NanoTime() - start_time2); 1981 } 1982 if (app_image) { 1983 bool forward_dex_cache_arrays = false; 1984 if (!AppImageClassLoadersAndDexCachesHelper::Update(this, 1985 space, 1986 class_loader, 1987 dex_caches, 1988 &temp_set, 1989 /*out*/&forward_dex_cache_arrays, 1990 /*out*/error_msg)) { 1991 return false; 1992 } 1993 // Update class loader and resolved strings. If added_class_table is false, the resolved 1994 // strings were forwarded UpdateAppImageClassLoadersAndDexCaches. 1995 UpdateClassLoaderVisitor visitor(space, class_loader.Get()); 1996 for (const ClassTable::TableSlot& root : temp_set) { 1997 visitor(root.Read()); 1998 } 1999 // forward_dex_cache_arrays is true iff we copied all of the dex cache arrays into the .bss. 2000 // In this case, madvise away the dex cache arrays section of the image to reduce RAM usage and 2001 // mark as PROT_NONE to catch any invalid accesses. 2002 if (forward_dex_cache_arrays) { 2003 const ImageSection& dex_cache_section = header.GetImageSection( 2004 ImageHeader::kSectionDexCacheArrays); 2005 uint8_t* section_begin = AlignUp(space->Begin() + dex_cache_section.Offset(), kPageSize); 2006 uint8_t* section_end = AlignDown(space->Begin() + dex_cache_section.End(), kPageSize); 2007 if (section_begin < section_end) { 2008 madvise(section_begin, section_end - section_begin, MADV_DONTNEED); 2009 mprotect(section_begin, section_end - section_begin, PROT_NONE); 2010 VLOG(image) << "Released and protected dex cache array image section from " 2011 << reinterpret_cast<const void*>(section_begin) << "-" 2012 << reinterpret_cast<const void*>(section_end); 2013 } 2014 } 2015 } 2016 if (!oat_file->GetBssGcRoots().empty()) { 2017 // Insert oat file to class table for visiting .bss GC roots. 2018 class_table->InsertOatFile(oat_file); 2019 } 2020 if (added_class_table) { 2021 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_); 2022 class_table->AddClassSet(std::move(temp_set)); 2023 } 2024 if (kIsDebugBuild && app_image) { 2025 // This verification needs to happen after the classes have been added to the class loader. 2026 // Since it ensures classes are in the class table. 2027 VerifyClassInTableArtMethodVisitor visitor2(class_table); 2028 header.VisitPackedArtMethods(&visitor2, space->Begin(), kRuntimePointerSize); 2029 // Verify that all direct interfaces of classes in the class table are also resolved. 2030 VerifyDirectInterfacesInTableClassVisitor visitor(class_loader.Get()); 2031 class_table->Visit(visitor); 2032 visitor.Check(); 2033 // Check that all non-primitive classes in dex caches are also in the class table. 2034 for (int32_t i = 0; i < dex_caches->GetLength(); i++) { 2035 ObjPtr<mirror::DexCache> dex_cache = dex_caches->Get(i); 2036 mirror::TypeDexCacheType* const types = dex_cache->GetResolvedTypes(); 2037 for (int32_t j = 0, num_types = dex_cache->NumResolvedTypes(); j < num_types; j++) { 2038 ObjPtr<mirror::Class> klass = types[j].load(std::memory_order_relaxed).object.Read(); 2039 if (klass != nullptr && !klass->IsPrimitive()) { 2040 CHECK(class_table->Contains(klass)) << klass->PrettyDescriptor() 2041 << " " << dex_cache->GetDexFile()->GetLocation(); 2042 } 2043 } 2044 } 2045 } 2046 VLOG(class_linker) << "Adding image space took " << PrettyDuration(NanoTime() - start_time); 2047 return true; 2048 } 2049 2050 bool ClassLinker::ClassInClassTable(ObjPtr<mirror::Class> klass) { 2051 ClassTable* const class_table = ClassTableForClassLoader(klass->GetClassLoader()); 2052 return class_table != nullptr && class_table->Contains(klass); 2053 } 2054 2055 void ClassLinker::VisitClassRoots(RootVisitor* visitor, VisitRootFlags flags) { 2056 // Acquire tracing_enabled before locking class linker lock to prevent lock order violation. Since 2057 // enabling tracing requires the mutator lock, there are no race conditions here. 2058 const bool tracing_enabled = Trace::IsTracingEnabled(); 2059 Thread* const self = Thread::Current(); 2060 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_); 2061 if (kUseReadBarrier) { 2062 // We do not track new roots for CC. 2063 DCHECK_EQ(0, flags & (kVisitRootFlagNewRoots | 2064 kVisitRootFlagClearRootLog | 2065 kVisitRootFlagStartLoggingNewRoots | 2066 kVisitRootFlagStopLoggingNewRoots)); 2067 } 2068 if ((flags & kVisitRootFlagAllRoots) != 0) { 2069 // Argument for how root visiting deals with ArtField and ArtMethod roots. 2070 // There is 3 GC cases to handle: 2071 // Non moving concurrent: 2072 // This case is easy to handle since the reference members of ArtMethod and ArtFields are held 2073 // live by the class and class roots. 2074 // 2075 // Moving non-concurrent: 2076 // This case needs to call visit VisitNativeRoots in case the classes or dex cache arrays move. 2077 // To prevent missing roots, this case needs to ensure that there is no 2078 // suspend points between the point which we allocate ArtMethod arrays and place them in a 2079 // class which is in the class table. 2080 // 2081 // Moving concurrent: 2082 // Need to make sure to not copy ArtMethods without doing read barriers since the roots are 2083 // marked concurrently and we don't hold the classlinker_classes_lock_ when we do the copy. 2084 // 2085 // Use an unbuffered visitor since the class table uses a temporary GcRoot for holding decoded 2086 // ClassTable::TableSlot. The buffered root visiting would access a stale stack location for 2087 // these objects. 2088 UnbufferedRootVisitor root_visitor(visitor, RootInfo(kRootStickyClass)); 2089 boot_class_table_->VisitRoots(root_visitor); 2090 // If tracing is enabled, then mark all the class loaders to prevent unloading. 2091 if ((flags & kVisitRootFlagClassLoader) != 0 || tracing_enabled) { 2092 for (const ClassLoaderData& data : class_loaders_) { 2093 GcRoot<mirror::Object> root(GcRoot<mirror::Object>(self->DecodeJObject(data.weak_root))); 2094 root.VisitRoot(visitor, RootInfo(kRootVMInternal)); 2095 } 2096 } 2097 } else if (!kUseReadBarrier && (flags & kVisitRootFlagNewRoots) != 0) { 2098 for (auto& root : new_class_roots_) { 2099 ObjPtr<mirror::Class> old_ref = root.Read<kWithoutReadBarrier>(); 2100 root.VisitRoot(visitor, RootInfo(kRootStickyClass)); 2101 ObjPtr<mirror::Class> new_ref = root.Read<kWithoutReadBarrier>(); 2102 // Concurrent moving GC marked new roots through the to-space invariant. 2103 CHECK_EQ(new_ref, old_ref); 2104 } 2105 for (const OatFile* oat_file : new_bss_roots_boot_oat_files_) { 2106 for (GcRoot<mirror::Object>& root : oat_file->GetBssGcRoots()) { 2107 ObjPtr<mirror::Object> old_ref = root.Read<kWithoutReadBarrier>(); 2108 if (old_ref != nullptr) { 2109 DCHECK(old_ref->IsClass()); 2110 root.VisitRoot(visitor, RootInfo(kRootStickyClass)); 2111 ObjPtr<mirror::Object> new_ref = root.Read<kWithoutReadBarrier>(); 2112 // Concurrent moving GC marked new roots through the to-space invariant. 2113 CHECK_EQ(new_ref, old_ref); 2114 } 2115 } 2116 } 2117 } 2118 if (!kUseReadBarrier && (flags & kVisitRootFlagClearRootLog) != 0) { 2119 new_class_roots_.clear(); 2120 new_bss_roots_boot_oat_files_.clear(); 2121 } 2122 if (!kUseReadBarrier && (flags & kVisitRootFlagStartLoggingNewRoots) != 0) { 2123 log_new_roots_ = true; 2124 } else if (!kUseReadBarrier && (flags & kVisitRootFlagStopLoggingNewRoots) != 0) { 2125 log_new_roots_ = false; 2126 } 2127 // We deliberately ignore the class roots in the image since we 2128 // handle image roots by using the MS/CMS rescanning of dirty cards. 2129 } 2130 2131 // Keep in sync with InitCallback. Anything we visit, we need to 2132 // reinit references to when reinitializing a ClassLinker from a 2133 // mapped image. 2134 void ClassLinker::VisitRoots(RootVisitor* visitor, VisitRootFlags flags) { 2135 class_roots_.VisitRootIfNonNull(visitor, RootInfo(kRootVMInternal)); 2136 VisitClassRoots(visitor, flags); 2137 array_iftable_.VisitRootIfNonNull(visitor, RootInfo(kRootVMInternal)); 2138 // Instead of visiting the find_array_class_cache_ drop it so that it doesn't prevent class 2139 // unloading if we are marking roots. 2140 DropFindArrayClassCache(); 2141 } 2142 2143 class VisitClassLoaderClassesVisitor : public ClassLoaderVisitor { 2144 public: 2145 explicit VisitClassLoaderClassesVisitor(ClassVisitor* visitor) 2146 : visitor_(visitor), 2147 done_(false) {} 2148 2149 void Visit(ObjPtr<mirror::ClassLoader> class_loader) 2150 REQUIRES_SHARED(Locks::classlinker_classes_lock_, Locks::mutator_lock_) OVERRIDE { 2151 ClassTable* const class_table = class_loader->GetClassTable(); 2152 if (!done_ && class_table != nullptr) { 2153 DefiningClassLoaderFilterVisitor visitor(class_loader, visitor_); 2154 if (!class_table->Visit(visitor)) { 2155 // If the visitor ClassTable returns false it means that we don't need to continue. 2156 done_ = true; 2157 } 2158 } 2159 } 2160 2161 private: 2162 // Class visitor that limits the class visits from a ClassTable to the classes with 2163 // the provided defining class loader. This filter is used to avoid multiple visits 2164 // of the same class which can be recorded for multiple initiating class loaders. 2165 class DefiningClassLoaderFilterVisitor : public ClassVisitor { 2166 public: 2167 DefiningClassLoaderFilterVisitor(ObjPtr<mirror::ClassLoader> defining_class_loader, 2168 ClassVisitor* visitor) 2169 : defining_class_loader_(defining_class_loader), visitor_(visitor) { } 2170 2171 bool operator()(ObjPtr<mirror::Class> klass) OVERRIDE REQUIRES_SHARED(Locks::mutator_lock_) { 2172 if (klass->GetClassLoader() != defining_class_loader_) { 2173 return true; 2174 } 2175 return (*visitor_)(klass); 2176 } 2177 2178 ObjPtr<mirror::ClassLoader> const defining_class_loader_; 2179 ClassVisitor* const visitor_; 2180 }; 2181 2182 ClassVisitor* const visitor_; 2183 // If done is true then we don't need to do any more visiting. 2184 bool done_; 2185 }; 2186 2187 void ClassLinker::VisitClassesInternal(ClassVisitor* visitor) { 2188 if (boot_class_table_->Visit(*visitor)) { 2189 VisitClassLoaderClassesVisitor loader_visitor(visitor); 2190 VisitClassLoaders(&loader_visitor); 2191 } 2192 } 2193 2194 void ClassLinker::VisitClasses(ClassVisitor* visitor) { 2195 Thread* const self = Thread::Current(); 2196 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 2197 // Not safe to have thread suspension when we are holding a lock. 2198 if (self != nullptr) { 2199 ScopedAssertNoThreadSuspension nts(__FUNCTION__); 2200 VisitClassesInternal(visitor); 2201 } else { 2202 VisitClassesInternal(visitor); 2203 } 2204 } 2205 2206 class GetClassesInToVector : public ClassVisitor { 2207 public: 2208 bool operator()(ObjPtr<mirror::Class> klass) OVERRIDE { 2209 classes_.push_back(klass); 2210 return true; 2211 } 2212 std::vector<ObjPtr<mirror::Class>> classes_; 2213 }; 2214 2215 class GetClassInToObjectArray : public ClassVisitor { 2216 public: 2217 explicit GetClassInToObjectArray(mirror::ObjectArray<mirror::Class>* arr) 2218 : arr_(arr), index_(0) {} 2219 2220 bool operator()(ObjPtr<mirror::Class> klass) OVERRIDE REQUIRES_SHARED(Locks::mutator_lock_) { 2221 ++index_; 2222 if (index_ <= arr_->GetLength()) { 2223 arr_->Set(index_ - 1, klass); 2224 return true; 2225 } 2226 return false; 2227 } 2228 2229 bool Succeeded() const REQUIRES_SHARED(Locks::mutator_lock_) { 2230 return index_ <= arr_->GetLength(); 2231 } 2232 2233 private: 2234 mirror::ObjectArray<mirror::Class>* const arr_; 2235 int32_t index_; 2236 }; 2237 2238 void ClassLinker::VisitClassesWithoutClassesLock(ClassVisitor* visitor) { 2239 // TODO: it may be possible to avoid secondary storage if we iterate over dex caches. The problem 2240 // is avoiding duplicates. 2241 if (!kMovingClasses) { 2242 ScopedAssertNoThreadSuspension nts(__FUNCTION__); 2243 GetClassesInToVector accumulator; 2244 VisitClasses(&accumulator); 2245 for (ObjPtr<mirror::Class> klass : accumulator.classes_) { 2246 if (!visitor->operator()(klass)) { 2247 return; 2248 } 2249 } 2250 } else { 2251 Thread* const self = Thread::Current(); 2252 StackHandleScope<1> hs(self); 2253 auto classes = hs.NewHandle<mirror::ObjectArray<mirror::Class>>(nullptr); 2254 // We size the array assuming classes won't be added to the class table during the visit. 2255 // If this assumption fails we iterate again. 2256 while (true) { 2257 size_t class_table_size; 2258 { 2259 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 2260 // Add 100 in case new classes get loaded when we are filling in the object array. 2261 class_table_size = NumZygoteClasses() + NumNonZygoteClasses() + 100; 2262 } 2263 ObjPtr<mirror::Class> class_type = mirror::Class::GetJavaLangClass(); 2264 ObjPtr<mirror::Class> array_of_class = FindArrayClass(self, &class_type); 2265 classes.Assign( 2266 mirror::ObjectArray<mirror::Class>::Alloc(self, array_of_class, class_table_size)); 2267 CHECK(classes != nullptr); // OOME. 2268 GetClassInToObjectArray accumulator(classes.Get()); 2269 VisitClasses(&accumulator); 2270 if (accumulator.Succeeded()) { 2271 break; 2272 } 2273 } 2274 for (int32_t i = 0; i < classes->GetLength(); ++i) { 2275 // If the class table shrank during creation of the clases array we expect null elements. If 2276 // the class table grew then the loop repeats. If classes are created after the loop has 2277 // finished then we don't visit. 2278 ObjPtr<mirror::Class> klass = classes->Get(i); 2279 if (klass != nullptr && !visitor->operator()(klass)) { 2280 return; 2281 } 2282 } 2283 } 2284 } 2285 2286 ClassLinker::~ClassLinker() { 2287 mirror::Class::ResetClass(); 2288 mirror::Constructor::ResetClass(); 2289 mirror::Field::ResetClass(); 2290 mirror::Method::ResetClass(); 2291 mirror::Reference::ResetClass(); 2292 mirror::StackTraceElement::ResetClass(); 2293 mirror::String::ResetClass(); 2294 mirror::Throwable::ResetClass(); 2295 mirror::BooleanArray::ResetArrayClass(); 2296 mirror::ByteArray::ResetArrayClass(); 2297 mirror::CharArray::ResetArrayClass(); 2298 mirror::Constructor::ResetArrayClass(); 2299 mirror::DoubleArray::ResetArrayClass(); 2300 mirror::Field::ResetArrayClass(); 2301 mirror::FloatArray::ResetArrayClass(); 2302 mirror::Method::ResetArrayClass(); 2303 mirror::IntArray::ResetArrayClass(); 2304 mirror::LongArray::ResetArrayClass(); 2305 mirror::ShortArray::ResetArrayClass(); 2306 mirror::MethodType::ResetClass(); 2307 mirror::MethodHandleImpl::ResetClass(); 2308 mirror::MethodHandlesLookup::ResetClass(); 2309 mirror::CallSite::ResetClass(); 2310 mirror::EmulatedStackFrame::ResetClass(); 2311 Thread* const self = Thread::Current(); 2312 for (const ClassLoaderData& data : class_loaders_) { 2313 DeleteClassLoader(self, data); 2314 } 2315 class_loaders_.clear(); 2316 } 2317 2318 void ClassLinker::DeleteClassLoader(Thread* self, const ClassLoaderData& data) { 2319 Runtime* const runtime = Runtime::Current(); 2320 JavaVMExt* const vm = runtime->GetJavaVM(); 2321 vm->DeleteWeakGlobalRef(self, data.weak_root); 2322 // Notify the JIT that we need to remove the methods and/or profiling info. 2323 if (runtime->GetJit() != nullptr) { 2324 jit::JitCodeCache* code_cache = runtime->GetJit()->GetCodeCache(); 2325 if (code_cache != nullptr) { 2326 // For the JIT case, RemoveMethodsIn removes the CHA dependencies. 2327 code_cache->RemoveMethodsIn(self, *data.allocator); 2328 } 2329 } else if (cha_ != nullptr) { 2330 // If we don't have a JIT, we need to manually remove the CHA dependencies manually. 2331 cha_->RemoveDependenciesForLinearAlloc(data.allocator); 2332 } 2333 delete data.allocator; 2334 delete data.class_table; 2335 } 2336 2337 mirror::PointerArray* ClassLinker::AllocPointerArray(Thread* self, size_t length) { 2338 return down_cast<mirror::PointerArray*>( 2339 image_pointer_size_ == PointerSize::k64 2340 ? static_cast<mirror::Array*>(mirror::LongArray::Alloc(self, length)) 2341 : static_cast<mirror::Array*>(mirror::IntArray::Alloc(self, length))); 2342 } 2343 2344 mirror::DexCache* ClassLinker::AllocDexCache(ObjPtr<mirror::String>* out_location, 2345 Thread* self, 2346 const DexFile& dex_file) { 2347 StackHandleScope<1> hs(self); 2348 DCHECK(out_location != nullptr); 2349 auto dex_cache(hs.NewHandle(ObjPtr<mirror::DexCache>::DownCast( 2350 GetClassRoot(kJavaLangDexCache)->AllocObject(self)))); 2351 if (dex_cache == nullptr) { 2352 self->AssertPendingOOMException(); 2353 return nullptr; 2354 } 2355 ObjPtr<mirror::String> location = intern_table_->InternStrong(dex_file.GetLocation().c_str()); 2356 if (location == nullptr) { 2357 self->AssertPendingOOMException(); 2358 return nullptr; 2359 } 2360 *out_location = location; 2361 return dex_cache.Get(); 2362 } 2363 2364 mirror::DexCache* ClassLinker::AllocAndInitializeDexCache(Thread* self, 2365 const DexFile& dex_file, 2366 LinearAlloc* linear_alloc) { 2367 ObjPtr<mirror::String> location = nullptr; 2368 ObjPtr<mirror::DexCache> dex_cache = AllocDexCache(&location, self, dex_file); 2369 if (dex_cache != nullptr) { 2370 WriterMutexLock mu(self, *Locks::dex_lock_); 2371 DCHECK(location != nullptr); 2372 mirror::DexCache::InitializeDexCache(self, 2373 dex_cache, 2374 location, 2375 &dex_file, 2376 linear_alloc, 2377 image_pointer_size_); 2378 } 2379 return dex_cache.Ptr(); 2380 } 2381 2382 mirror::Class* ClassLinker::AllocClass(Thread* self, 2383 ObjPtr<mirror::Class> java_lang_Class, 2384 uint32_t class_size) { 2385 DCHECK_GE(class_size, sizeof(mirror::Class)); 2386 gc::Heap* heap = Runtime::Current()->GetHeap(); 2387 mirror::Class::InitializeClassVisitor visitor(class_size); 2388 ObjPtr<mirror::Object> k = kMovingClasses ? 2389 heap->AllocObject<true>(self, java_lang_Class, class_size, visitor) : 2390 heap->AllocNonMovableObject<true>(self, java_lang_Class, class_size, visitor); 2391 if (UNLIKELY(k == nullptr)) { 2392 self->AssertPendingOOMException(); 2393 return nullptr; 2394 } 2395 return k->AsClass(); 2396 } 2397 2398 mirror::Class* ClassLinker::AllocClass(Thread* self, uint32_t class_size) { 2399 return AllocClass(self, GetClassRoot(kJavaLangClass), class_size); 2400 } 2401 2402 mirror::ObjectArray<mirror::StackTraceElement>* ClassLinker::AllocStackTraceElementArray( 2403 Thread* self, 2404 size_t length) { 2405 return mirror::ObjectArray<mirror::StackTraceElement>::Alloc( 2406 self, GetClassRoot(kJavaLangStackTraceElementArrayClass), length); 2407 } 2408 2409 mirror::Class* ClassLinker::EnsureResolved(Thread* self, 2410 const char* descriptor, 2411 ObjPtr<mirror::Class> klass) { 2412 DCHECK(klass != nullptr); 2413 if (kIsDebugBuild) { 2414 StackHandleScope<1> hs(self); 2415 HandleWrapperObjPtr<mirror::Class> h = hs.NewHandleWrapper(&klass); 2416 Thread::PoisonObjectPointersIfDebug(); 2417 } 2418 2419 // For temporary classes we must wait for them to be retired. 2420 if (init_done_ && klass->IsTemp()) { 2421 CHECK(!klass->IsResolved()); 2422 if (klass->IsErroneousUnresolved()) { 2423 ThrowEarlierClassFailure(klass); 2424 return nullptr; 2425 } 2426 StackHandleScope<1> hs(self); 2427 Handle<mirror::Class> h_class(hs.NewHandle(klass)); 2428 ObjectLock<mirror::Class> lock(self, h_class); 2429 // Loop and wait for the resolving thread to retire this class. 2430 while (!h_class->IsRetired() && !h_class->IsErroneousUnresolved()) { 2431 lock.WaitIgnoringInterrupts(); 2432 } 2433 if (h_class->IsErroneousUnresolved()) { 2434 ThrowEarlierClassFailure(h_class.Get()); 2435 return nullptr; 2436 } 2437 CHECK(h_class->IsRetired()); 2438 // Get the updated class from class table. 2439 klass = LookupClass(self, descriptor, h_class.Get()->GetClassLoader()); 2440 } 2441 2442 // Wait for the class if it has not already been linked. 2443 size_t index = 0; 2444 // Maximum number of yield iterations until we start sleeping. 2445 static const size_t kNumYieldIterations = 1000; 2446 // How long each sleep is in us. 2447 static const size_t kSleepDurationUS = 1000; // 1 ms. 2448 while (!klass->IsResolved() && !klass->IsErroneousUnresolved()) { 2449 StackHandleScope<1> hs(self); 2450 HandleWrapperObjPtr<mirror::Class> h_class(hs.NewHandleWrapper(&klass)); 2451 { 2452 ObjectTryLock<mirror::Class> lock(self, h_class); 2453 // Can not use a monitor wait here since it may block when returning and deadlock if another 2454 // thread has locked klass. 2455 if (lock.Acquired()) { 2456 // Check for circular dependencies between classes, the lock is required for SetStatus. 2457 if (!h_class->IsResolved() && h_class->GetClinitThreadId() == self->GetTid()) { 2458 ThrowClassCircularityError(h_class.Get()); 2459 mirror::Class::SetStatus(h_class, mirror::Class::kStatusErrorUnresolved, self); 2460 return nullptr; 2461 } 2462 } 2463 } 2464 { 2465 // Handle wrapper deals with klass moving. 2466 ScopedThreadSuspension sts(self, kSuspended); 2467 if (index < kNumYieldIterations) { 2468 sched_yield(); 2469 } else { 2470 usleep(kSleepDurationUS); 2471 } 2472 } 2473 ++index; 2474 } 2475 2476 if (klass->IsErroneousUnresolved()) { 2477 ThrowEarlierClassFailure(klass); 2478 return nullptr; 2479 } 2480 // Return the loaded class. No exceptions should be pending. 2481 CHECK(klass->IsResolved()) << klass->PrettyClass(); 2482 self->AssertNoPendingException(); 2483 return klass.Ptr(); 2484 } 2485 2486 typedef std::pair<const DexFile*, const DexFile::ClassDef*> ClassPathEntry; 2487 2488 // Search a collection of DexFiles for a descriptor 2489 ClassPathEntry FindInClassPath(const char* descriptor, 2490 size_t hash, const std::vector<const DexFile*>& class_path) { 2491 for (const DexFile* dex_file : class_path) { 2492 const DexFile::ClassDef* dex_class_def = OatDexFile::FindClassDef(*dex_file, descriptor, hash); 2493 if (dex_class_def != nullptr) { 2494 return ClassPathEntry(dex_file, dex_class_def); 2495 } 2496 } 2497 return ClassPathEntry(nullptr, nullptr); 2498 } 2499 2500 bool ClassLinker::FindClassInBaseDexClassLoader(ScopedObjectAccessAlreadyRunnable& soa, 2501 Thread* self, 2502 const char* descriptor, 2503 size_t hash, 2504 Handle<mirror::ClassLoader> class_loader, 2505 ObjPtr<mirror::Class>* result) { 2506 // Termination case: boot class loader. 2507 if (IsBootClassLoader(soa, class_loader.Get())) { 2508 *result = FindClassInBootClassLoaderClassPath(self, descriptor, hash); 2509 return true; 2510 } 2511 2512 if (IsPathOrDexClassLoader(soa, class_loader)) { 2513 // For regular path or dex class loader the search order is: 2514 // - parent 2515 // - class loader dex files 2516 2517 // Handles as RegisterDexFile may allocate dex caches (and cause thread suspension). 2518 StackHandleScope<1> hs(self); 2519 Handle<mirror::ClassLoader> h_parent(hs.NewHandle(class_loader->GetParent())); 2520 if (!FindClassInBaseDexClassLoader(soa, self, descriptor, hash, h_parent, result)) { 2521 return false; // One of the parents is not supported. 2522 } 2523 if (*result != nullptr) { 2524 return true; // Found the class up the chain. 2525 } 2526 2527 // Search the current class loader classpath. 2528 *result = FindClassInBaseDexClassLoaderClassPath(soa, descriptor, hash, class_loader); 2529 return true; 2530 } 2531 2532 if (IsDelegateLastClassLoader(soa, class_loader)) { 2533 // For delegate last, the search order is: 2534 // - boot class path 2535 // - class loader dex files 2536 // - parent 2537 *result = FindClassInBootClassLoaderClassPath(self, descriptor, hash); 2538 if (*result != nullptr) { 2539 return true; // The class is part of the boot class path. 2540 } 2541 2542 *result = FindClassInBaseDexClassLoaderClassPath(soa, descriptor, hash, class_loader); 2543 if (*result != nullptr) { 2544 return true; // Found the class in the current class loader 2545 } 2546 2547 // Handles as RegisterDexFile may allocate dex caches (and cause thread suspension). 2548 StackHandleScope<1> hs(self); 2549 Handle<mirror::ClassLoader> h_parent(hs.NewHandle(class_loader->GetParent())); 2550 return FindClassInBaseDexClassLoader(soa, self, descriptor, hash, h_parent, result); 2551 } 2552 2553 // Unsupported class loader. 2554 *result = nullptr; 2555 return false; 2556 } 2557 2558 // Finds the class in the boot class loader. 2559 // If the class is found the method returns the resolved class. Otherwise it returns null. 2560 ObjPtr<mirror::Class> ClassLinker::FindClassInBootClassLoaderClassPath(Thread* self, 2561 const char* descriptor, 2562 size_t hash) { 2563 ObjPtr<mirror::Class> result = nullptr; 2564 ClassPathEntry pair = FindInClassPath(descriptor, hash, boot_class_path_); 2565 if (pair.second != nullptr) { 2566 ObjPtr<mirror::Class> klass = LookupClass(self, descriptor, hash, nullptr); 2567 if (klass != nullptr) { 2568 result = EnsureResolved(self, descriptor, klass); 2569 } else { 2570 result = DefineClass(self, 2571 descriptor, 2572 hash, 2573 ScopedNullHandle<mirror::ClassLoader>(), 2574 *pair.first, 2575 *pair.second); 2576 } 2577 if (result == nullptr) { 2578 CHECK(self->IsExceptionPending()) << descriptor; 2579 self->ClearException(); 2580 } 2581 } 2582 return result; 2583 } 2584 2585 ObjPtr<mirror::Class> ClassLinker::FindClassInBaseDexClassLoaderClassPath( 2586 ScopedObjectAccessAlreadyRunnable& soa, 2587 const char* descriptor, 2588 size_t hash, 2589 Handle<mirror::ClassLoader> class_loader) { 2590 CHECK(IsPathOrDexClassLoader(soa, class_loader) || IsDelegateLastClassLoader(soa, class_loader)) 2591 << "Unexpected class loader for descriptor " << descriptor; 2592 2593 Thread* self = soa.Self(); 2594 ArtField* const cookie_field = 2595 jni::DecodeArtField(WellKnownClasses::dalvik_system_DexFile_cookie); 2596 ArtField* const dex_file_field = 2597 jni::DecodeArtField(WellKnownClasses::dalvik_system_DexPathList__Element_dexFile); 2598 ObjPtr<mirror::Object> dex_path_list = 2599 jni::DecodeArtField(WellKnownClasses::dalvik_system_BaseDexClassLoader_pathList)-> 2600 GetObject(class_loader.Get()); 2601 if (dex_path_list != nullptr && dex_file_field != nullptr && cookie_field != nullptr) { 2602 // DexPathList has an array dexElements of Elements[] which each contain a dex file. 2603 ObjPtr<mirror::Object> dex_elements_obj = 2604 jni::DecodeArtField(WellKnownClasses::dalvik_system_DexPathList_dexElements)-> 2605 GetObject(dex_path_list); 2606 // Loop through each dalvik.system.DexPathList$Element's dalvik.system.DexFile and look 2607 // at the mCookie which is a DexFile vector. 2608 if (dex_elements_obj != nullptr) { 2609 StackHandleScope<1> hs(self); 2610 Handle<mirror::ObjectArray<mirror::Object>> dex_elements = 2611 hs.NewHandle(dex_elements_obj->AsObjectArray<mirror::Object>()); 2612 for (int32_t i = 0; i < dex_elements->GetLength(); ++i) { 2613 ObjPtr<mirror::Object> element = dex_elements->GetWithoutChecks(i); 2614 if (element == nullptr) { 2615 // Should never happen, fall back to java code to throw a NPE. 2616 break; 2617 } 2618 ObjPtr<mirror::Object> dex_file = dex_file_field->GetObject(element); 2619 if (dex_file != nullptr) { 2620 ObjPtr<mirror::LongArray> long_array = cookie_field->GetObject(dex_file)->AsLongArray(); 2621 if (long_array == nullptr) { 2622 // This should never happen so log a warning. 2623 LOG(WARNING) << "Null DexFile::mCookie for " << descriptor; 2624 break; 2625 } 2626 int32_t long_array_size = long_array->GetLength(); 2627 // First element is the oat file. 2628 for (int32_t j = kDexFileIndexStart; j < long_array_size; ++j) { 2629 const DexFile* cp_dex_file = reinterpret_cast<const DexFile*>(static_cast<uintptr_t>( 2630 long_array->GetWithoutChecks(j))); 2631 const DexFile::ClassDef* dex_class_def = 2632 OatDexFile::FindClassDef(*cp_dex_file, descriptor, hash); 2633 if (dex_class_def != nullptr) { 2634 ObjPtr<mirror::Class> klass = DefineClass(self, 2635 descriptor, 2636 hash, 2637 class_loader, 2638 *cp_dex_file, 2639 *dex_class_def); 2640 if (klass == nullptr) { 2641 CHECK(self->IsExceptionPending()) << descriptor; 2642 self->ClearException(); 2643 // TODO: Is it really right to break here, and not check the other dex files? 2644 return nullptr; 2645 } 2646 return klass; 2647 } 2648 } 2649 } 2650 } 2651 } 2652 self->AssertNoPendingException(); 2653 } 2654 return nullptr; 2655 } 2656 2657 mirror::Class* ClassLinker::FindClass(Thread* self, 2658 const char* descriptor, 2659 Handle<mirror::ClassLoader> class_loader) { 2660 DCHECK_NE(*descriptor, '\0') << "descriptor is empty string"; 2661 DCHECK(self != nullptr); 2662 self->AssertNoPendingException(); 2663 self->PoisonObjectPointers(); // For DefineClass, CreateArrayClass, etc... 2664 if (descriptor[1] == '\0') { 2665 // only the descriptors of primitive types should be 1 character long, also avoid class lookup 2666 // for primitive classes that aren't backed by dex files. 2667 return FindPrimitiveClass(descriptor[0]); 2668 } 2669 const size_t hash = ComputeModifiedUtf8Hash(descriptor); 2670 // Find the class in the loaded classes table. 2671 ObjPtr<mirror::Class> klass = LookupClass(self, descriptor, hash, class_loader.Get()); 2672 if (klass != nullptr) { 2673 return EnsureResolved(self, descriptor, klass); 2674 } 2675 // Class is not yet loaded. 2676 if (descriptor[0] != '[' && class_loader == nullptr) { 2677 // Non-array class and the boot class loader, search the boot class path. 2678 ClassPathEntry pair = FindInClassPath(descriptor, hash, boot_class_path_); 2679 if (pair.second != nullptr) { 2680 return DefineClass(self, 2681 descriptor, 2682 hash, 2683 ScopedNullHandle<mirror::ClassLoader>(), 2684 *pair.first, 2685 *pair.second); 2686 } else { 2687 // The boot class loader is searched ahead of the application class loader, failures are 2688 // expected and will be wrapped in a ClassNotFoundException. Use the pre-allocated error to 2689 // trigger the chaining with a proper stack trace. 2690 ObjPtr<mirror::Throwable> pre_allocated = 2691 Runtime::Current()->GetPreAllocatedNoClassDefFoundError(); 2692 self->SetException(pre_allocated); 2693 return nullptr; 2694 } 2695 } 2696 ObjPtr<mirror::Class> result_ptr; 2697 bool descriptor_equals; 2698 if (descriptor[0] == '[') { 2699 result_ptr = CreateArrayClass(self, descriptor, hash, class_loader); 2700 DCHECK_EQ(result_ptr == nullptr, self->IsExceptionPending()); 2701 DCHECK(result_ptr == nullptr || result_ptr->DescriptorEquals(descriptor)); 2702 descriptor_equals = true; 2703 } else { 2704 ScopedObjectAccessUnchecked soa(self); 2705 bool known_hierarchy = 2706 FindClassInBaseDexClassLoader(soa, self, descriptor, hash, class_loader, &result_ptr); 2707 if (result_ptr != nullptr) { 2708 // The chain was understood and we found the class. We still need to add the class to 2709 // the class table to protect from racy programs that can try and redefine the path list 2710 // which would change the Class<?> returned for subsequent evaluation of const-class. 2711 DCHECK(known_hierarchy); 2712 DCHECK(result_ptr->DescriptorEquals(descriptor)); 2713 descriptor_equals = true; 2714 } else { 2715 // Either the chain wasn't understood or the class wasn't found. 2716 // 2717 // If the chain was understood but we did not find the class, let the Java-side 2718 // rediscover all this and throw the exception with the right stack trace. Note that 2719 // the Java-side could still succeed for racy programs if another thread is actively 2720 // modifying the class loader's path list. 2721 2722 if (!self->CanCallIntoJava()) { 2723 // Oops, we can't call into java so we can't run actual class-loader code. 2724 // This is true for e.g. for the compiler (jit or aot). 2725 ObjPtr<mirror::Throwable> pre_allocated = 2726 Runtime::Current()->GetPreAllocatedNoClassDefFoundError(); 2727 self->SetException(pre_allocated); 2728 return nullptr; 2729 } 2730 2731 // Inlined DescriptorToDot(descriptor) with extra validation. 2732 // 2733 // Throw NoClassDefFoundError early rather than potentially load a class only to fail 2734 // the DescriptorEquals() check below and give a confusing error message. For example, 2735 // when native code erroneously calls JNI GetFieldId() with signature "java/lang/String" 2736 // instead of "Ljava/lang/String;", the message below using the "dot" names would be 2737 // "class loader [...] returned class java.lang.String instead of java.lang.String". 2738 size_t descriptor_length = strlen(descriptor); 2739 if (UNLIKELY(descriptor[0] != 'L') || 2740 UNLIKELY(descriptor[descriptor_length - 1] != ';') || 2741 UNLIKELY(memchr(descriptor + 1, '.', descriptor_length - 2) != nullptr)) { 2742 ThrowNoClassDefFoundError("Invalid descriptor: %s.", descriptor); 2743 return nullptr; 2744 } 2745 std::string class_name_string(descriptor + 1, descriptor_length - 2); 2746 std::replace(class_name_string.begin(), class_name_string.end(), '/', '.'); 2747 2748 ScopedLocalRef<jobject> class_loader_object( 2749 soa.Env(), soa.AddLocalReference<jobject>(class_loader.Get())); 2750 ScopedLocalRef<jobject> result(soa.Env(), nullptr); 2751 { 2752 ScopedThreadStateChange tsc(self, kNative); 2753 ScopedLocalRef<jobject> class_name_object( 2754 soa.Env(), soa.Env()->NewStringUTF(class_name_string.c_str())); 2755 if (class_name_object.get() == nullptr) { 2756 DCHECK(self->IsExceptionPending()); // OOME. 2757 return nullptr; 2758 } 2759 CHECK(class_loader_object.get() != nullptr); 2760 result.reset(soa.Env()->CallObjectMethod(class_loader_object.get(), 2761 WellKnownClasses::java_lang_ClassLoader_loadClass, 2762 class_name_object.get())); 2763 } 2764 if (result.get() == nullptr && !self->IsExceptionPending()) { 2765 // broken loader - throw NPE to be compatible with Dalvik 2766 ThrowNullPointerException(StringPrintf("ClassLoader.loadClass returned null for %s", 2767 class_name_string.c_str()).c_str()); 2768 return nullptr; 2769 } 2770 result_ptr = soa.Decode<mirror::Class>(result.get()); 2771 // Check the name of the returned class. 2772 descriptor_equals = (result_ptr != nullptr) && result_ptr->DescriptorEquals(descriptor); 2773 } 2774 } 2775 2776 if (self->IsExceptionPending()) { 2777 // If the ClassLoader threw or array class allocation failed, pass that exception up. 2778 // However, to comply with the RI behavior, first check if another thread succeeded. 2779 result_ptr = LookupClass(self, descriptor, hash, class_loader.Get()); 2780 if (result_ptr != nullptr && !result_ptr->IsErroneous()) { 2781 self->ClearException(); 2782 return EnsureResolved(self, descriptor, result_ptr); 2783 } 2784 return nullptr; 2785 } 2786 2787 // Try to insert the class to the class table, checking for mismatch. 2788 ObjPtr<mirror::Class> old; 2789 { 2790 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_); 2791 ClassTable* const class_table = InsertClassTableForClassLoader(class_loader.Get()); 2792 old = class_table->Lookup(descriptor, hash); 2793 if (old == nullptr) { 2794 old = result_ptr; // For the comparison below, after releasing the lock. 2795 if (descriptor_equals) { 2796 class_table->InsertWithHash(result_ptr.Ptr(), hash); 2797 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(class_loader.Get()); 2798 } // else throw below, after releasing the lock. 2799 } 2800 } 2801 if (UNLIKELY(old != result_ptr)) { 2802 // Return `old` (even if `!descriptor_equals`) to mimic the RI behavior for parallel 2803 // capable class loaders. (All class loaders are considered parallel capable on Android.) 2804 mirror::Class* loader_class = class_loader->GetClass(); 2805 const char* loader_class_name = 2806 loader_class->GetDexFile().StringByTypeIdx(loader_class->GetDexTypeIndex()); 2807 LOG(WARNING) << "Initiating class loader of type " << DescriptorToDot(loader_class_name) 2808 << " is not well-behaved; it returned a different Class for racing loadClass(\"" 2809 << DescriptorToDot(descriptor) << "\")."; 2810 return EnsureResolved(self, descriptor, old); 2811 } 2812 if (UNLIKELY(!descriptor_equals)) { 2813 std::string result_storage; 2814 const char* result_name = result_ptr->GetDescriptor(&result_storage); 2815 std::string loader_storage; 2816 const char* loader_class_name = class_loader->GetClass()->GetDescriptor(&loader_storage); 2817 ThrowNoClassDefFoundError( 2818 "Initiating class loader of type %s returned class %s instead of %s.", 2819 DescriptorToDot(loader_class_name).c_str(), 2820 DescriptorToDot(result_name).c_str(), 2821 DescriptorToDot(descriptor).c_str()); 2822 return nullptr; 2823 } 2824 // success, return mirror::Class* 2825 return result_ptr.Ptr(); 2826 } 2827 2828 mirror::Class* ClassLinker::DefineClass(Thread* self, 2829 const char* descriptor, 2830 size_t hash, 2831 Handle<mirror::ClassLoader> class_loader, 2832 const DexFile& dex_file, 2833 const DexFile::ClassDef& dex_class_def) { 2834 StackHandleScope<3> hs(self); 2835 auto klass = hs.NewHandle<mirror::Class>(nullptr); 2836 2837 // Load the class from the dex file. 2838 if (UNLIKELY(!init_done_)) { 2839 // finish up init of hand crafted class_roots_ 2840 if (strcmp(descriptor, "Ljava/lang/Object;") == 0) { 2841 klass.Assign(GetClassRoot(kJavaLangObject)); 2842 } else if (strcmp(descriptor, "Ljava/lang/Class;") == 0) { 2843 klass.Assign(GetClassRoot(kJavaLangClass)); 2844 } else if (strcmp(descriptor, "Ljava/lang/String;") == 0) { 2845 klass.Assign(GetClassRoot(kJavaLangString)); 2846 } else if (strcmp(descriptor, "Ljava/lang/ref/Reference;") == 0) { 2847 klass.Assign(GetClassRoot(kJavaLangRefReference)); 2848 } else if (strcmp(descriptor, "Ljava/lang/DexCache;") == 0) { 2849 klass.Assign(GetClassRoot(kJavaLangDexCache)); 2850 } else if (strcmp(descriptor, "Ldalvik/system/ClassExt;") == 0) { 2851 klass.Assign(GetClassRoot(kDalvikSystemClassExt)); 2852 } 2853 } 2854 2855 if (klass == nullptr) { 2856 // Allocate a class with the status of not ready. 2857 // Interface object should get the right size here. Regular class will 2858 // figure out the right size later and be replaced with one of the right 2859 // size when the class becomes resolved. 2860 klass.Assign(AllocClass(self, SizeOfClassWithoutEmbeddedTables(dex_file, dex_class_def))); 2861 } 2862 if (UNLIKELY(klass == nullptr)) { 2863 self->AssertPendingOOMException(); 2864 return nullptr; 2865 } 2866 // Get the real dex file. This will return the input if there aren't any callbacks or they do 2867 // nothing. 2868 DexFile const* new_dex_file = nullptr; 2869 DexFile::ClassDef const* new_class_def = nullptr; 2870 // TODO We should ideally figure out some way to move this after we get a lock on the klass so it 2871 // will only be called once. 2872 Runtime::Current()->GetRuntimeCallbacks()->ClassPreDefine(descriptor, 2873 klass, 2874 class_loader, 2875 dex_file, 2876 dex_class_def, 2877 &new_dex_file, 2878 &new_class_def); 2879 // Check to see if an exception happened during runtime callbacks. Return if so. 2880 if (self->IsExceptionPending()) { 2881 return nullptr; 2882 } 2883 ObjPtr<mirror::DexCache> dex_cache = RegisterDexFile(*new_dex_file, class_loader.Get()); 2884 if (dex_cache == nullptr) { 2885 self->AssertPendingException(); 2886 return nullptr; 2887 } 2888 klass->SetDexCache(dex_cache); 2889 SetupClass(*new_dex_file, *new_class_def, klass, class_loader.Get()); 2890 2891 // Mark the string class by setting its access flag. 2892 if (UNLIKELY(!init_done_)) { 2893 if (strcmp(descriptor, "Ljava/lang/String;") == 0) { 2894 klass->SetStringClass(); 2895 } 2896 } 2897 2898 ObjectLock<mirror::Class> lock(self, klass); 2899 klass->SetClinitThreadId(self->GetTid()); 2900 // Make sure we have a valid empty iftable even if there are errors. 2901 klass->SetIfTable(GetClassRoot(kJavaLangObject)->GetIfTable()); 2902 2903 // Add the newly loaded class to the loaded classes table. 2904 ObjPtr<mirror::Class> existing = InsertClass(descriptor, klass.Get(), hash); 2905 if (existing != nullptr) { 2906 // We failed to insert because we raced with another thread. Calling EnsureResolved may cause 2907 // this thread to block. 2908 return EnsureResolved(self, descriptor, existing); 2909 } 2910 2911 // Load the fields and other things after we are inserted in the table. This is so that we don't 2912 // end up allocating unfree-able linear alloc resources and then lose the race condition. The 2913 // other reason is that the field roots are only visited from the class table. So we need to be 2914 // inserted before we allocate / fill in these fields. 2915 LoadClass(self, *new_dex_file, *new_class_def, klass); 2916 if (self->IsExceptionPending()) { 2917 VLOG(class_linker) << self->GetException()->Dump(); 2918 // An exception occured during load, set status to erroneous while holding klass' lock in case 2919 // notification is necessary. 2920 if (!klass->IsErroneous()) { 2921 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorUnresolved, self); 2922 } 2923 return nullptr; 2924 } 2925 2926 // Finish loading (if necessary) by finding parents 2927 CHECK(!klass->IsLoaded()); 2928 if (!LoadSuperAndInterfaces(klass, *new_dex_file)) { 2929 // Loading failed. 2930 if (!klass->IsErroneous()) { 2931 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorUnresolved, self); 2932 } 2933 return nullptr; 2934 } 2935 CHECK(klass->IsLoaded()); 2936 2937 // At this point the class is loaded. Publish a ClassLoad event. 2938 // Note: this may be a temporary class. It is a listener's responsibility to handle this. 2939 Runtime::Current()->GetRuntimeCallbacks()->ClassLoad(klass); 2940 2941 // Link the class (if necessary) 2942 CHECK(!klass->IsResolved()); 2943 // TODO: Use fast jobjects? 2944 auto interfaces = hs.NewHandle<mirror::ObjectArray<mirror::Class>>(nullptr); 2945 2946 MutableHandle<mirror::Class> h_new_class = hs.NewHandle<mirror::Class>(nullptr); 2947 if (!LinkClass(self, descriptor, klass, interfaces, &h_new_class)) { 2948 // Linking failed. 2949 if (!klass->IsErroneous()) { 2950 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorUnresolved, self); 2951 } 2952 return nullptr; 2953 } 2954 self->AssertNoPendingException(); 2955 CHECK(h_new_class != nullptr) << descriptor; 2956 CHECK(h_new_class->IsResolved() && !h_new_class->IsErroneousResolved()) << descriptor; 2957 2958 // Instrumentation may have updated entrypoints for all methods of all 2959 // classes. However it could not update methods of this class while we 2960 // were loading it. Now the class is resolved, we can update entrypoints 2961 // as required by instrumentation. 2962 if (Runtime::Current()->GetInstrumentation()->AreExitStubsInstalled()) { 2963 // We must be in the kRunnable state to prevent instrumentation from 2964 // suspending all threads to update entrypoints while we are doing it 2965 // for this class. 2966 DCHECK_EQ(self->GetState(), kRunnable); 2967 Runtime::Current()->GetInstrumentation()->InstallStubsForClass(h_new_class.Get()); 2968 } 2969 2970 /* 2971 * We send CLASS_PREPARE events to the debugger from here. The 2972 * definition of "preparation" is creating the static fields for a 2973 * class and initializing them to the standard default values, but not 2974 * executing any code (that comes later, during "initialization"). 2975 * 2976 * We did the static preparation in LinkClass. 2977 * 2978 * The class has been prepared and resolved but possibly not yet verified 2979 * at this point. 2980 */ 2981 Runtime::Current()->GetRuntimeCallbacks()->ClassPrepare(klass, h_new_class); 2982 2983 // Notify native debugger of the new class and its layout. 2984 jit::Jit::NewTypeLoadedIfUsingJit(h_new_class.Get()); 2985 2986 return h_new_class.Get(); 2987 } 2988 2989 uint32_t ClassLinker::SizeOfClassWithoutEmbeddedTables(const DexFile& dex_file, 2990 const DexFile::ClassDef& dex_class_def) { 2991 const uint8_t* class_data = dex_file.GetClassData(dex_class_def); 2992 size_t num_ref = 0; 2993 size_t num_8 = 0; 2994 size_t num_16 = 0; 2995 size_t num_32 = 0; 2996 size_t num_64 = 0; 2997 if (class_data != nullptr) { 2998 // We allow duplicate definitions of the same field in a class_data_item 2999 // but ignore the repeated indexes here, b/21868015. 3000 uint32_t last_field_idx = DexFile::kDexNoIndex; 3001 for (ClassDataItemIterator it(dex_file, class_data); it.HasNextStaticField(); it.Next()) { 3002 uint32_t field_idx = it.GetMemberIndex(); 3003 // Ordering enforced by DexFileVerifier. 3004 DCHECK(last_field_idx == DexFile::kDexNoIndex || last_field_idx <= field_idx); 3005 if (UNLIKELY(field_idx == last_field_idx)) { 3006 continue; 3007 } 3008 last_field_idx = field_idx; 3009 const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx); 3010 const char* descriptor = dex_file.GetFieldTypeDescriptor(field_id); 3011 char c = descriptor[0]; 3012 switch (c) { 3013 case 'L': 3014 case '[': 3015 num_ref++; 3016 break; 3017 case 'J': 3018 case 'D': 3019 num_64++; 3020 break; 3021 case 'I': 3022 case 'F': 3023 num_32++; 3024 break; 3025 case 'S': 3026 case 'C': 3027 num_16++; 3028 break; 3029 case 'B': 3030 case 'Z': 3031 num_8++; 3032 break; 3033 default: 3034 LOG(FATAL) << "Unknown descriptor: " << c; 3035 UNREACHABLE(); 3036 } 3037 } 3038 } 3039 return mirror::Class::ComputeClassSize(false, 3040 0, 3041 num_8, 3042 num_16, 3043 num_32, 3044 num_64, 3045 num_ref, 3046 image_pointer_size_); 3047 } 3048 3049 // Special case to get oat code without overwriting a trampoline. 3050 const void* ClassLinker::GetQuickOatCodeFor(ArtMethod* method) { 3051 CHECK(method->IsInvokable()) << method->PrettyMethod(); 3052 if (method->IsProxyMethod()) { 3053 return GetQuickProxyInvokeHandler(); 3054 } 3055 auto* code = method->GetOatMethodQuickCode(GetImagePointerSize()); 3056 if (code != nullptr) { 3057 return code; 3058 } 3059 if (method->IsNative()) { 3060 // No code and native? Use generic trampoline. 3061 return GetQuickGenericJniStub(); 3062 } 3063 return GetQuickToInterpreterBridge(); 3064 } 3065 3066 bool ClassLinker::ShouldUseInterpreterEntrypoint(ArtMethod* method, const void* quick_code) { 3067 if (UNLIKELY(method->IsNative() || method->IsProxyMethod())) { 3068 return false; 3069 } 3070 3071 if (quick_code == nullptr) { 3072 return true; 3073 } 3074 3075 Runtime* runtime = Runtime::Current(); 3076 instrumentation::Instrumentation* instr = runtime->GetInstrumentation(); 3077 if (instr->InterpretOnly()) { 3078 return true; 3079 } 3080 3081 if (runtime->GetClassLinker()->IsQuickToInterpreterBridge(quick_code)) { 3082 // Doing this check avoids doing compiled/interpreter transitions. 3083 return true; 3084 } 3085 3086 if (Dbg::IsForcedInterpreterNeededForCalling(Thread::Current(), method)) { 3087 // Force the use of interpreter when it is required by the debugger. 3088 return true; 3089 } 3090 3091 if (runtime->IsJavaDebuggable()) { 3092 // For simplicity, we ignore precompiled code and go to the interpreter 3093 // assuming we don't already have jitted code. 3094 // We could look at the oat file where `quick_code` is being defined, 3095 // and check whether it's been compiled debuggable, but we decided to 3096 // only rely on the JIT for debuggable apps. 3097 jit::Jit* jit = Runtime::Current()->GetJit(); 3098 return (jit == nullptr) || !jit->GetCodeCache()->ContainsPc(quick_code); 3099 } 3100 3101 if (runtime->IsNativeDebuggable()) { 3102 DCHECK(runtime->UseJitCompilation() && runtime->GetJit()->JitAtFirstUse()); 3103 // If we are doing native debugging, ignore application's AOT code, 3104 // since we want to JIT it (at first use) with extra stackmaps for native 3105 // debugging. We keep however all AOT code from the boot image, 3106 // since the JIT-at-first-use is blocking and would result in non-negligible 3107 // startup performance impact. 3108 return !runtime->GetHeap()->IsInBootImageOatFile(quick_code); 3109 } 3110 3111 return false; 3112 } 3113 3114 void ClassLinker::FixupStaticTrampolines(ObjPtr<mirror::Class> klass) { 3115 DCHECK(klass->IsInitialized()) << klass->PrettyDescriptor(); 3116 if (klass->NumDirectMethods() == 0) { 3117 return; // No direct methods => no static methods. 3118 } 3119 Runtime* runtime = Runtime::Current(); 3120 if (!runtime->IsStarted()) { 3121 if (runtime->IsAotCompiler() || runtime->GetHeap()->HasBootImageSpace()) { 3122 return; // OAT file unavailable. 3123 } 3124 } 3125 3126 const DexFile& dex_file = klass->GetDexFile(); 3127 const DexFile::ClassDef* dex_class_def = klass->GetClassDef(); 3128 CHECK(dex_class_def != nullptr); 3129 const uint8_t* class_data = dex_file.GetClassData(*dex_class_def); 3130 // There should always be class data if there were direct methods. 3131 CHECK(class_data != nullptr) << klass->PrettyDescriptor(); 3132 ClassDataItemIterator it(dex_file, class_data); 3133 it.SkipAllFields(); 3134 bool has_oat_class; 3135 OatFile::OatClass oat_class = OatFile::FindOatClass(dex_file, 3136 klass->GetDexClassDefIndex(), 3137 &has_oat_class); 3138 // Link the code of methods skipped by LinkCode. 3139 for (size_t method_index = 0; it.HasNextDirectMethod(); ++method_index, it.Next()) { 3140 ArtMethod* method = klass->GetDirectMethod(method_index, image_pointer_size_); 3141 if (!method->IsStatic()) { 3142 // Only update static methods. 3143 continue; 3144 } 3145 const void* quick_code = nullptr; 3146 if (has_oat_class) { 3147 OatFile::OatMethod oat_method = oat_class.GetOatMethod(method_index); 3148 quick_code = oat_method.GetQuickCode(); 3149 } 3150 // Check whether the method is native, in which case it's generic JNI. 3151 if (quick_code == nullptr && method->IsNative()) { 3152 quick_code = GetQuickGenericJniStub(); 3153 } else if (ShouldUseInterpreterEntrypoint(method, quick_code)) { 3154 // Use interpreter entry point. 3155 quick_code = GetQuickToInterpreterBridge(); 3156 } 3157 runtime->GetInstrumentation()->UpdateMethodsCode(method, quick_code); 3158 } 3159 // Ignore virtual methods on the iterator. 3160 } 3161 3162 // Does anything needed to make sure that the compiler will not generate a direct invoke to this 3163 // method. Should only be called on non-invokable methods. 3164 inline void EnsureThrowsInvocationError(ClassLinker* class_linker, ArtMethod* method) { 3165 DCHECK(method != nullptr); 3166 DCHECK(!method->IsInvokable()); 3167 method->SetEntryPointFromQuickCompiledCodePtrSize( 3168 class_linker->GetQuickToInterpreterBridgeTrampoline(), 3169 class_linker->GetImagePointerSize()); 3170 } 3171 3172 static void LinkCode(ClassLinker* class_linker, 3173 ArtMethod* method, 3174 const OatFile::OatClass* oat_class, 3175 uint32_t class_def_method_index) REQUIRES_SHARED(Locks::mutator_lock_) { 3176 Runtime* const runtime = Runtime::Current(); 3177 if (runtime->IsAotCompiler()) { 3178 // The following code only applies to a non-compiler runtime. 3179 return; 3180 } 3181 // Method shouldn't have already been linked. 3182 DCHECK(method->GetEntryPointFromQuickCompiledCode() == nullptr); 3183 if (oat_class != nullptr) { 3184 // Every kind of method should at least get an invoke stub from the oat_method. 3185 // non-abstract methods also get their code pointers. 3186 const OatFile::OatMethod oat_method = oat_class->GetOatMethod(class_def_method_index); 3187 oat_method.LinkMethod(method); 3188 } 3189 3190 // Install entry point from interpreter. 3191 const void* quick_code = method->GetEntryPointFromQuickCompiledCode(); 3192 bool enter_interpreter = class_linker->ShouldUseInterpreterEntrypoint(method, quick_code); 3193 3194 if (!method->IsInvokable()) { 3195 EnsureThrowsInvocationError(class_linker, method); 3196 return; 3197 } 3198 3199 if (method->IsStatic() && !method->IsConstructor()) { 3200 // For static methods excluding the class initializer, install the trampoline. 3201 // It will be replaced by the proper entry point by ClassLinker::FixupStaticTrampolines 3202 // after initializing class (see ClassLinker::InitializeClass method). 3203 method->SetEntryPointFromQuickCompiledCode(GetQuickResolutionStub()); 3204 } else if (quick_code == nullptr && method->IsNative()) { 3205 method->SetEntryPointFromQuickCompiledCode(GetQuickGenericJniStub()); 3206 } else if (enter_interpreter) { 3207 // Set entry point from compiled code if there's no code or in interpreter only mode. 3208 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge()); 3209 } 3210 3211 if (method->IsNative()) { 3212 // Unregistering restores the dlsym lookup stub. 3213 method->UnregisterNative(); 3214 3215 if (enter_interpreter || quick_code == nullptr) { 3216 // We have a native method here without code. Then it should have either the generic JNI 3217 // trampoline as entrypoint (non-static), or the resolution trampoline (static). 3218 // TODO: this doesn't handle all the cases where trampolines may be installed. 3219 const void* entry_point = method->GetEntryPointFromQuickCompiledCode(); 3220 DCHECK(class_linker->IsQuickGenericJniStub(entry_point) || 3221 class_linker->IsQuickResolutionStub(entry_point)); 3222 } 3223 } 3224 } 3225 3226 void ClassLinker::SetupClass(const DexFile& dex_file, 3227 const DexFile::ClassDef& dex_class_def, 3228 Handle<mirror::Class> klass, 3229 ObjPtr<mirror::ClassLoader> class_loader) { 3230 CHECK(klass != nullptr); 3231 CHECK(klass->GetDexCache() != nullptr); 3232 CHECK_EQ(mirror::Class::kStatusNotReady, klass->GetStatus()); 3233 const char* descriptor = dex_file.GetClassDescriptor(dex_class_def); 3234 CHECK(descriptor != nullptr); 3235 3236 klass->SetClass(GetClassRoot(kJavaLangClass)); 3237 uint32_t access_flags = dex_class_def.GetJavaAccessFlags(); 3238 CHECK_EQ(access_flags & ~kAccJavaFlagsMask, 0U); 3239 klass->SetAccessFlags(access_flags); 3240 klass->SetClassLoader(class_loader); 3241 DCHECK_EQ(klass->GetPrimitiveType(), Primitive::kPrimNot); 3242 mirror::Class::SetStatus(klass, mirror::Class::kStatusIdx, nullptr); 3243 3244 klass->SetDexClassDefIndex(dex_file.GetIndexForClassDef(dex_class_def)); 3245 klass->SetDexTypeIndex(dex_class_def.class_idx_); 3246 } 3247 3248 void ClassLinker::LoadClass(Thread* self, 3249 const DexFile& dex_file, 3250 const DexFile::ClassDef& dex_class_def, 3251 Handle<mirror::Class> klass) { 3252 const uint8_t* class_data = dex_file.GetClassData(dex_class_def); 3253 if (class_data == nullptr) { 3254 return; // no fields or methods - for example a marker interface 3255 } 3256 LoadClassMembers(self, dex_file, class_data, klass); 3257 } 3258 3259 LengthPrefixedArray<ArtField>* ClassLinker::AllocArtFieldArray(Thread* self, 3260 LinearAlloc* allocator, 3261 size_t length) { 3262 if (length == 0) { 3263 return nullptr; 3264 } 3265 // If the ArtField alignment changes, review all uses of LengthPrefixedArray<ArtField>. 3266 static_assert(alignof(ArtField) == 4, "ArtField alignment is expected to be 4."); 3267 size_t storage_size = LengthPrefixedArray<ArtField>::ComputeSize(length); 3268 void* array_storage = allocator->Alloc(self, storage_size); 3269 auto* ret = new(array_storage) LengthPrefixedArray<ArtField>(length); 3270 CHECK(ret != nullptr); 3271 std::uninitialized_fill_n(&ret->At(0), length, ArtField()); 3272 return ret; 3273 } 3274 3275 LengthPrefixedArray<ArtMethod>* ClassLinker::AllocArtMethodArray(Thread* self, 3276 LinearAlloc* allocator, 3277 size_t length) { 3278 if (length == 0) { 3279 return nullptr; 3280 } 3281 const size_t method_alignment = ArtMethod::Alignment(image_pointer_size_); 3282 const size_t method_size = ArtMethod::Size(image_pointer_size_); 3283 const size_t storage_size = 3284 LengthPrefixedArray<ArtMethod>::ComputeSize(length, method_size, method_alignment); 3285 void* array_storage = allocator->Alloc(self, storage_size); 3286 auto* ret = new (array_storage) LengthPrefixedArray<ArtMethod>(length); 3287 CHECK(ret != nullptr); 3288 for (size_t i = 0; i < length; ++i) { 3289 new(reinterpret_cast<void*>(&ret->At(i, method_size, method_alignment))) ArtMethod; 3290 } 3291 return ret; 3292 } 3293 3294 LinearAlloc* ClassLinker::GetAllocatorForClassLoader(ObjPtr<mirror::ClassLoader> class_loader) { 3295 if (class_loader == nullptr) { 3296 return Runtime::Current()->GetLinearAlloc(); 3297 } 3298 LinearAlloc* allocator = class_loader->GetAllocator(); 3299 DCHECK(allocator != nullptr); 3300 return allocator; 3301 } 3302 3303 LinearAlloc* ClassLinker::GetOrCreateAllocatorForClassLoader(ObjPtr<mirror::ClassLoader> class_loader) { 3304 if (class_loader == nullptr) { 3305 return Runtime::Current()->GetLinearAlloc(); 3306 } 3307 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 3308 LinearAlloc* allocator = class_loader->GetAllocator(); 3309 if (allocator == nullptr) { 3310 RegisterClassLoader(class_loader); 3311 allocator = class_loader->GetAllocator(); 3312 CHECK(allocator != nullptr); 3313 } 3314 return allocator; 3315 } 3316 3317 void ClassLinker::LoadClassMembers(Thread* self, 3318 const DexFile& dex_file, 3319 const uint8_t* class_data, 3320 Handle<mirror::Class> klass) { 3321 { 3322 // Note: We cannot have thread suspension until the field and method arrays are setup or else 3323 // Class::VisitFieldRoots may miss some fields or methods. 3324 ScopedAssertNoThreadSuspension nts(__FUNCTION__); 3325 // Load static fields. 3326 // We allow duplicate definitions of the same field in a class_data_item 3327 // but ignore the repeated indexes here, b/21868015. 3328 LinearAlloc* const allocator = GetAllocatorForClassLoader(klass->GetClassLoader()); 3329 ClassDataItemIterator it(dex_file, class_data); 3330 LengthPrefixedArray<ArtField>* sfields = AllocArtFieldArray(self, 3331 allocator, 3332 it.NumStaticFields()); 3333 size_t num_sfields = 0; 3334 uint32_t last_field_idx = 0u; 3335 for (; it.HasNextStaticField(); it.Next()) { 3336 uint32_t field_idx = it.GetMemberIndex(); 3337 DCHECK_GE(field_idx, last_field_idx); // Ordering enforced by DexFileVerifier. 3338 if (num_sfields == 0 || LIKELY(field_idx > last_field_idx)) { 3339 DCHECK_LT(num_sfields, it.NumStaticFields()); 3340 LoadField(it, klass, &sfields->At(num_sfields)); 3341 ++num_sfields; 3342 last_field_idx = field_idx; 3343 } 3344 } 3345 3346 // Load instance fields. 3347 LengthPrefixedArray<ArtField>* ifields = AllocArtFieldArray(self, 3348 allocator, 3349 it.NumInstanceFields()); 3350 size_t num_ifields = 0u; 3351 last_field_idx = 0u; 3352 for (; it.HasNextInstanceField(); it.Next()) { 3353 uint32_t field_idx = it.GetMemberIndex(); 3354 DCHECK_GE(field_idx, last_field_idx); // Ordering enforced by DexFileVerifier. 3355 if (num_ifields == 0 || LIKELY(field_idx > last_field_idx)) { 3356 DCHECK_LT(num_ifields, it.NumInstanceFields()); 3357 LoadField(it, klass, &ifields->At(num_ifields)); 3358 ++num_ifields; 3359 last_field_idx = field_idx; 3360 } 3361 } 3362 3363 if (UNLIKELY(num_sfields != it.NumStaticFields()) || 3364 UNLIKELY(num_ifields != it.NumInstanceFields())) { 3365 LOG(WARNING) << "Duplicate fields in class " << klass->PrettyDescriptor() 3366 << " (unique static fields: " << num_sfields << "/" << it.NumStaticFields() 3367 << ", unique instance fields: " << num_ifields << "/" << it.NumInstanceFields() << ")"; 3368 // NOTE: Not shrinking the over-allocated sfields/ifields, just setting size. 3369 if (sfields != nullptr) { 3370 sfields->SetSize(num_sfields); 3371 } 3372 if (ifields != nullptr) { 3373 ifields->SetSize(num_ifields); 3374 } 3375 } 3376 // Set the field arrays. 3377 klass->SetSFieldsPtr(sfields); 3378 DCHECK_EQ(klass->NumStaticFields(), num_sfields); 3379 klass->SetIFieldsPtr(ifields); 3380 DCHECK_EQ(klass->NumInstanceFields(), num_ifields); 3381 // Load methods. 3382 bool has_oat_class = false; 3383 const OatFile::OatClass oat_class = 3384 (Runtime::Current()->IsStarted() && !Runtime::Current()->IsAotCompiler()) 3385 ? OatFile::FindOatClass(dex_file, klass->GetDexClassDefIndex(), &has_oat_class) 3386 : OatFile::OatClass::Invalid(); 3387 const OatFile::OatClass* oat_class_ptr = has_oat_class ? &oat_class : nullptr; 3388 klass->SetMethodsPtr( 3389 AllocArtMethodArray(self, allocator, it.NumDirectMethods() + it.NumVirtualMethods()), 3390 it.NumDirectMethods(), 3391 it.NumVirtualMethods()); 3392 size_t class_def_method_index = 0; 3393 uint32_t last_dex_method_index = DexFile::kDexNoIndex; 3394 size_t last_class_def_method_index = 0; 3395 // TODO These should really use the iterators. 3396 for (size_t i = 0; it.HasNextDirectMethod(); i++, it.Next()) { 3397 ArtMethod* method = klass->GetDirectMethodUnchecked(i, image_pointer_size_); 3398 LoadMethod(dex_file, it, klass, method); 3399 LinkCode(this, method, oat_class_ptr, class_def_method_index); 3400 uint32_t it_method_index = it.GetMemberIndex(); 3401 if (last_dex_method_index == it_method_index) { 3402 // duplicate case 3403 method->SetMethodIndex(last_class_def_method_index); 3404 } else { 3405 method->SetMethodIndex(class_def_method_index); 3406 last_dex_method_index = it_method_index; 3407 last_class_def_method_index = class_def_method_index; 3408 } 3409 class_def_method_index++; 3410 } 3411 for (size_t i = 0; it.HasNextVirtualMethod(); i++, it.Next()) { 3412 ArtMethod* method = klass->GetVirtualMethodUnchecked(i, image_pointer_size_); 3413 LoadMethod(dex_file, it, klass, method); 3414 DCHECK_EQ(class_def_method_index, it.NumDirectMethods() + i); 3415 LinkCode(this, method, oat_class_ptr, class_def_method_index); 3416 class_def_method_index++; 3417 } 3418 DCHECK(!it.HasNext()); 3419 } 3420 // Ensure that the card is marked so that remembered sets pick up native roots. 3421 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(klass.Get()); 3422 self->AllowThreadSuspension(); 3423 } 3424 3425 void ClassLinker::LoadField(const ClassDataItemIterator& it, 3426 Handle<mirror::Class> klass, 3427 ArtField* dst) { 3428 const uint32_t field_idx = it.GetMemberIndex(); 3429 dst->SetDexFieldIndex(field_idx); 3430 dst->SetDeclaringClass(klass.Get()); 3431 dst->SetAccessFlags(it.GetFieldAccessFlags()); 3432 } 3433 3434 void ClassLinker::LoadMethod(const DexFile& dex_file, 3435 const ClassDataItemIterator& it, 3436 Handle<mirror::Class> klass, 3437 ArtMethod* dst) { 3438 uint32_t dex_method_idx = it.GetMemberIndex(); 3439 const DexFile::MethodId& method_id = dex_file.GetMethodId(dex_method_idx); 3440 const char* method_name = dex_file.StringDataByIdx(method_id.name_idx_); 3441 3442 ScopedAssertNoThreadSuspension ants("LoadMethod"); 3443 dst->SetDexMethodIndex(dex_method_idx); 3444 dst->SetDeclaringClass(klass.Get()); 3445 dst->SetCodeItemOffset(it.GetMethodCodeItemOffset()); 3446 3447 dst->SetDexCacheResolvedMethods(klass->GetDexCache()->GetResolvedMethods(), image_pointer_size_); 3448 3449 uint32_t access_flags = it.GetMethodAccessFlags(); 3450 3451 if (UNLIKELY(strcmp("finalize", method_name) == 0)) { 3452 // Set finalizable flag on declaring class. 3453 if (strcmp("V", dex_file.GetShorty(method_id.proto_idx_)) == 0) { 3454 // Void return type. 3455 if (klass->GetClassLoader() != nullptr) { // All non-boot finalizer methods are flagged. 3456 klass->SetFinalizable(); 3457 } else { 3458 std::string temp; 3459 const char* klass_descriptor = klass->GetDescriptor(&temp); 3460 // The Enum class declares a "final" finalize() method to prevent subclasses from 3461 // introducing a finalizer. We don't want to set the finalizable flag for Enum or its 3462 // subclasses, so we exclude it here. 3463 // We also want to avoid setting the flag on Object, where we know that finalize() is 3464 // empty. 3465 if (strcmp(klass_descriptor, "Ljava/lang/Object;") != 0 && 3466 strcmp(klass_descriptor, "Ljava/lang/Enum;") != 0) { 3467 klass->SetFinalizable(); 3468 } 3469 } 3470 } 3471 } else if (method_name[0] == '<') { 3472 // Fix broken access flags for initializers. Bug 11157540. 3473 bool is_init = (strcmp("<init>", method_name) == 0); 3474 bool is_clinit = !is_init && (strcmp("<clinit>", method_name) == 0); 3475 if (UNLIKELY(!is_init && !is_clinit)) { 3476 LOG(WARNING) << "Unexpected '<' at start of method name " << method_name; 3477 } else { 3478 if (UNLIKELY((access_flags & kAccConstructor) == 0)) { 3479 LOG(WARNING) << method_name << " didn't have expected constructor access flag in class " 3480 << klass->PrettyDescriptor() << " in dex file " << dex_file.GetLocation(); 3481 access_flags |= kAccConstructor; 3482 } 3483 } 3484 } 3485 dst->SetAccessFlags(access_flags); 3486 } 3487 3488 void ClassLinker::AppendToBootClassPath(Thread* self, const DexFile& dex_file) { 3489 ObjPtr<mirror::DexCache> dex_cache = AllocAndInitializeDexCache( 3490 self, 3491 dex_file, 3492 Runtime::Current()->GetLinearAlloc()); 3493 CHECK(dex_cache != nullptr) << "Failed to allocate dex cache for " << dex_file.GetLocation(); 3494 AppendToBootClassPath(dex_file, dex_cache); 3495 } 3496 3497 void ClassLinker::AppendToBootClassPath(const DexFile& dex_file, 3498 ObjPtr<mirror::DexCache> dex_cache) { 3499 CHECK(dex_cache != nullptr) << dex_file.GetLocation(); 3500 boot_class_path_.push_back(&dex_file); 3501 RegisterBootClassPathDexFile(dex_file, dex_cache); 3502 } 3503 3504 void ClassLinker::RegisterDexFileLocked(const DexFile& dex_file, 3505 ObjPtr<mirror::DexCache> dex_cache, 3506 ObjPtr<mirror::ClassLoader> class_loader) { 3507 Thread* const self = Thread::Current(); 3508 Locks::dex_lock_->AssertExclusiveHeld(self); 3509 CHECK(dex_cache != nullptr) << dex_file.GetLocation(); 3510 // For app images, the dex cache location may be a suffix of the dex file location since the 3511 // dex file location is an absolute path. 3512 const std::string dex_cache_location = dex_cache->GetLocation()->ToModifiedUtf8(); 3513 const size_t dex_cache_length = dex_cache_location.length(); 3514 CHECK_GT(dex_cache_length, 0u) << dex_file.GetLocation(); 3515 std::string dex_file_location = dex_file.GetLocation(); 3516 CHECK_GE(dex_file_location.length(), dex_cache_length) 3517 << dex_cache_location << " " << dex_file.GetLocation(); 3518 // Take suffix. 3519 const std::string dex_file_suffix = dex_file_location.substr( 3520 dex_file_location.length() - dex_cache_length, 3521 dex_cache_length); 3522 // Example dex_cache location is SettingsProvider.apk and 3523 // dex file location is /system/priv-app/SettingsProvider/SettingsProvider.apk 3524 CHECK_EQ(dex_cache_location, dex_file_suffix); 3525 const OatFile* oat_file = 3526 (dex_file.GetOatDexFile() != nullptr) ? dex_file.GetOatDexFile()->GetOatFile() : nullptr; 3527 // Clean up pass to remove null dex caches. Also check if we need to initialize OatFile .bss. 3528 // Null dex caches can occur due to class unloading and we are lazily removing null entries. 3529 bool initialize_oat_file_bss = (oat_file != nullptr); 3530 JavaVMExt* const vm = self->GetJniEnv()->vm; 3531 for (auto it = dex_caches_.begin(); it != dex_caches_.end(); ) { 3532 DexCacheData data = *it; 3533 if (self->IsJWeakCleared(data.weak_root)) { 3534 vm->DeleteWeakGlobalRef(self, data.weak_root); 3535 it = dex_caches_.erase(it); 3536 } else { 3537 if (initialize_oat_file_bss && 3538 it->dex_file->GetOatDexFile() != nullptr && 3539 it->dex_file->GetOatDexFile()->GetOatFile() == oat_file) { 3540 initialize_oat_file_bss = false; // Already initialized. 3541 } 3542 ++it; 3543 } 3544 } 3545 if (initialize_oat_file_bss) { 3546 // TODO: Pre-initialize from boot/app image? 3547 ArtMethod* resolution_method = Runtime::Current()->GetResolutionMethod(); 3548 for (ArtMethod*& entry : oat_file->GetBssMethods()) { 3549 entry = resolution_method; 3550 } 3551 } 3552 jweak dex_cache_jweak = vm->AddWeakGlobalRef(self, dex_cache); 3553 dex_cache->SetDexFile(&dex_file); 3554 DexCacheData data; 3555 data.weak_root = dex_cache_jweak; 3556 data.dex_file = dex_cache->GetDexFile(); 3557 data.resolved_methods = dex_cache->GetResolvedMethods(); 3558 data.class_table = ClassTableForClassLoader(class_loader); 3559 DCHECK(data.class_table != nullptr); 3560 // Make sure to hold the dex cache live in the class table. This case happens for the boot class 3561 // path dex caches without an image. 3562 data.class_table->InsertStrongRoot(dex_cache); 3563 if (class_loader != nullptr) { 3564 // Since we added a strong root to the class table, do the write barrier as required for 3565 // remembered sets and generational GCs. 3566 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(class_loader); 3567 } 3568 dex_caches_.push_back(data); 3569 } 3570 3571 ObjPtr<mirror::DexCache> ClassLinker::DecodeDexCache(Thread* self, const DexCacheData& data) { 3572 return data.IsValid() 3573 ? ObjPtr<mirror::DexCache>::DownCast(self->DecodeJObject(data.weak_root)) 3574 : nullptr; 3575 } 3576 3577 ObjPtr<mirror::DexCache> ClassLinker::EnsureSameClassLoader( 3578 Thread* self, 3579 ObjPtr<mirror::DexCache> dex_cache, 3580 const DexCacheData& data, 3581 ObjPtr<mirror::ClassLoader> class_loader) { 3582 DCHECK_EQ(dex_cache->GetDexFile(), data.dex_file); 3583 if (data.class_table != ClassTableForClassLoader(class_loader)) { 3584 self->ThrowNewExceptionF("Ljava/lang/InternalError;", 3585 "Attempt to register dex file %s with multiple class loaders", 3586 data.dex_file->GetLocation().c_str()); 3587 return nullptr; 3588 } 3589 return dex_cache; 3590 } 3591 3592 void ClassLinker::RegisterExistingDexCache(ObjPtr<mirror::DexCache> dex_cache, 3593 ObjPtr<mirror::ClassLoader> class_loader) { 3594 Thread* self = Thread::Current(); 3595 StackHandleScope<2> hs(self); 3596 Handle<mirror::DexCache> h_dex_cache(hs.NewHandle(dex_cache)); 3597 Handle<mirror::ClassLoader> h_class_loader(hs.NewHandle(class_loader)); 3598 const DexFile* dex_file = dex_cache->GetDexFile(); 3599 DCHECK(dex_file != nullptr) << "Attempt to register uninitialized dex_cache object!"; 3600 if (kIsDebugBuild) { 3601 DexCacheData old_data; 3602 { 3603 ReaderMutexLock mu(self, *Locks::dex_lock_); 3604 old_data = FindDexCacheDataLocked(*dex_file); 3605 } 3606 ObjPtr<mirror::DexCache> old_dex_cache = DecodeDexCache(self, old_data); 3607 DCHECK(old_dex_cache.IsNull()) << "Attempt to manually register a dex cache thats already " 3608 << "been registered on dex file " << dex_file->GetLocation(); 3609 } 3610 ClassTable* table; 3611 { 3612 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_); 3613 table = InsertClassTableForClassLoader(h_class_loader.Get()); 3614 } 3615 WriterMutexLock mu(self, *Locks::dex_lock_); 3616 RegisterDexFileLocked(*dex_file, h_dex_cache.Get(), h_class_loader.Get()); 3617 table->InsertStrongRoot(h_dex_cache.Get()); 3618 if (h_class_loader.Get() != nullptr) { 3619 // Since we added a strong root to the class table, do the write barrier as required for 3620 // remembered sets and generational GCs. 3621 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(h_class_loader.Get()); 3622 } 3623 } 3624 3625 ObjPtr<mirror::DexCache> ClassLinker::RegisterDexFile(const DexFile& dex_file, 3626 ObjPtr<mirror::ClassLoader> class_loader) { 3627 Thread* self = Thread::Current(); 3628 DexCacheData old_data; 3629 { 3630 ReaderMutexLock mu(self, *Locks::dex_lock_); 3631 old_data = FindDexCacheDataLocked(dex_file); 3632 } 3633 ObjPtr<mirror::DexCache> old_dex_cache = DecodeDexCache(self, old_data); 3634 if (old_dex_cache != nullptr) { 3635 return EnsureSameClassLoader(self, old_dex_cache, old_data, class_loader); 3636 } 3637 LinearAlloc* const linear_alloc = GetOrCreateAllocatorForClassLoader(class_loader); 3638 DCHECK(linear_alloc != nullptr); 3639 ClassTable* table; 3640 { 3641 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_); 3642 table = InsertClassTableForClassLoader(class_loader); 3643 } 3644 // Don't alloc while holding the lock, since allocation may need to 3645 // suspend all threads and another thread may need the dex_lock_ to 3646 // get to a suspend point. 3647 StackHandleScope<3> hs(self); 3648 Handle<mirror::ClassLoader> h_class_loader(hs.NewHandle(class_loader)); 3649 ObjPtr<mirror::String> location; 3650 Handle<mirror::DexCache> h_dex_cache(hs.NewHandle(AllocDexCache(/*out*/&location, 3651 self, 3652 dex_file))); 3653 Handle<mirror::String> h_location(hs.NewHandle(location)); 3654 { 3655 WriterMutexLock mu(self, *Locks::dex_lock_); 3656 old_data = FindDexCacheDataLocked(dex_file); 3657 old_dex_cache = DecodeDexCache(self, old_data); 3658 if (old_dex_cache == nullptr && h_dex_cache != nullptr) { 3659 // Do InitializeDexCache while holding dex lock to make sure two threads don't call it at the 3660 // same time with the same dex cache. Since the .bss is shared this can cause failing DCHECK 3661 // that the arrays are null. 3662 mirror::DexCache::InitializeDexCache(self, 3663 h_dex_cache.Get(), 3664 h_location.Get(), 3665 &dex_file, 3666 linear_alloc, 3667 image_pointer_size_); 3668 RegisterDexFileLocked(dex_file, h_dex_cache.Get(), h_class_loader.Get()); 3669 } 3670 } 3671 if (old_dex_cache != nullptr) { 3672 // Another thread managed to initialize the dex cache faster, so use that DexCache. 3673 // If this thread encountered OOME, ignore it. 3674 DCHECK_EQ(h_dex_cache == nullptr, self->IsExceptionPending()); 3675 self->ClearException(); 3676 // We cannot call EnsureSameClassLoader() while holding the dex_lock_. 3677 return EnsureSameClassLoader(self, old_dex_cache, old_data, h_class_loader.Get()); 3678 } 3679 if (h_dex_cache == nullptr) { 3680 self->AssertPendingOOMException(); 3681 return nullptr; 3682 } 3683 table->InsertStrongRoot(h_dex_cache.Get()); 3684 if (h_class_loader.Get() != nullptr) { 3685 // Since we added a strong root to the class table, do the write barrier as required for 3686 // remembered sets and generational GCs. 3687 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(h_class_loader.Get()); 3688 } 3689 return h_dex_cache.Get(); 3690 } 3691 3692 void ClassLinker::RegisterBootClassPathDexFile(const DexFile& dex_file, 3693 ObjPtr<mirror::DexCache> dex_cache) { 3694 WriterMutexLock mu(Thread::Current(), *Locks::dex_lock_); 3695 RegisterDexFileLocked(dex_file, dex_cache, /* class_loader */ nullptr); 3696 } 3697 3698 bool ClassLinker::IsDexFileRegistered(Thread* self, const DexFile& dex_file) { 3699 ReaderMutexLock mu(self, *Locks::dex_lock_); 3700 return DecodeDexCache(self, FindDexCacheDataLocked(dex_file)) != nullptr; 3701 } 3702 3703 ObjPtr<mirror::DexCache> ClassLinker::FindDexCache(Thread* self, const DexFile& dex_file) { 3704 ReaderMutexLock mu(self, *Locks::dex_lock_); 3705 DexCacheData dex_cache_data = FindDexCacheDataLocked(dex_file); 3706 ObjPtr<mirror::DexCache> dex_cache = DecodeDexCache(self, dex_cache_data); 3707 if (dex_cache != nullptr) { 3708 return dex_cache; 3709 } 3710 // Failure, dump diagnostic and abort. 3711 for (const DexCacheData& data : dex_caches_) { 3712 if (DecodeDexCache(self, data) != nullptr) { 3713 LOG(FATAL_WITHOUT_ABORT) << "Registered dex file " << data.dex_file->GetLocation(); 3714 } 3715 } 3716 LOG(FATAL) << "Failed to find DexCache for DexFile " << dex_file.GetLocation() 3717 << " " << &dex_file << " " << dex_cache_data.dex_file; 3718 UNREACHABLE(); 3719 } 3720 3721 ClassTable* ClassLinker::FindClassTable(Thread* self, ObjPtr<mirror::DexCache> dex_cache) { 3722 const DexFile* dex_file = dex_cache->GetDexFile(); 3723 DCHECK(dex_file != nullptr); 3724 ReaderMutexLock mu(self, *Locks::dex_lock_); 3725 // Search assuming unique-ness of dex file. 3726 for (const DexCacheData& data : dex_caches_) { 3727 // Avoid decoding (and read barriers) other unrelated dex caches. 3728 if (data.dex_file == dex_file) { 3729 ObjPtr<mirror::DexCache> registered_dex_cache = DecodeDexCache(self, data); 3730 if (registered_dex_cache != nullptr) { 3731 CHECK_EQ(registered_dex_cache, dex_cache) << dex_file->GetLocation(); 3732 return data.class_table; 3733 } 3734 } 3735 } 3736 return nullptr; 3737 } 3738 3739 ClassLinker::DexCacheData ClassLinker::FindDexCacheDataLocked(const DexFile& dex_file) { 3740 // Search assuming unique-ness of dex file. 3741 for (const DexCacheData& data : dex_caches_) { 3742 // Avoid decoding (and read barriers) other unrelated dex caches. 3743 if (data.dex_file == &dex_file) { 3744 return data; 3745 } 3746 } 3747 return DexCacheData(); 3748 } 3749 3750 mirror::Class* ClassLinker::CreatePrimitiveClass(Thread* self, Primitive::Type type) { 3751 ObjPtr<mirror::Class> klass = 3752 AllocClass(self, mirror::Class::PrimitiveClassSize(image_pointer_size_)); 3753 if (UNLIKELY(klass == nullptr)) { 3754 self->AssertPendingOOMException(); 3755 return nullptr; 3756 } 3757 return InitializePrimitiveClass(klass, type); 3758 } 3759 3760 mirror::Class* ClassLinker::InitializePrimitiveClass(ObjPtr<mirror::Class> primitive_class, 3761 Primitive::Type type) { 3762 CHECK(primitive_class != nullptr); 3763 // Must hold lock on object when initializing. 3764 Thread* self = Thread::Current(); 3765 StackHandleScope<1> hs(self); 3766 Handle<mirror::Class> h_class(hs.NewHandle(primitive_class)); 3767 ObjectLock<mirror::Class> lock(self, h_class); 3768 h_class->SetAccessFlags(kAccPublic | kAccFinal | kAccAbstract); 3769 h_class->SetPrimitiveType(type); 3770 h_class->SetIfTable(GetClassRoot(kJavaLangObject)->GetIfTable()); 3771 mirror::Class::SetStatus(h_class, mirror::Class::kStatusInitialized, self); 3772 const char* descriptor = Primitive::Descriptor(type); 3773 ObjPtr<mirror::Class> existing = InsertClass(descriptor, 3774 h_class.Get(), 3775 ComputeModifiedUtf8Hash(descriptor)); 3776 CHECK(existing == nullptr) << "InitPrimitiveClass(" << type << ") failed"; 3777 return h_class.Get(); 3778 } 3779 3780 // Create an array class (i.e. the class object for the array, not the 3781 // array itself). "descriptor" looks like "[C" or "[[[[B" or 3782 // "[Ljava/lang/String;". 3783 // 3784 // If "descriptor" refers to an array of primitives, look up the 3785 // primitive type's internally-generated class object. 3786 // 3787 // "class_loader" is the class loader of the class that's referring to 3788 // us. It's used to ensure that we're looking for the element type in 3789 // the right context. It does NOT become the class loader for the 3790 // array class; that always comes from the base element class. 3791 // 3792 // Returns null with an exception raised on failure. 3793 mirror::Class* ClassLinker::CreateArrayClass(Thread* self, const char* descriptor, size_t hash, 3794 Handle<mirror::ClassLoader> class_loader) { 3795 // Identify the underlying component type 3796 CHECK_EQ('[', descriptor[0]); 3797 StackHandleScope<2> hs(self); 3798 MutableHandle<mirror::Class> component_type(hs.NewHandle(FindClass(self, descriptor + 1, 3799 class_loader))); 3800 if (component_type == nullptr) { 3801 DCHECK(self->IsExceptionPending()); 3802 // We need to accept erroneous classes as component types. 3803 const size_t component_hash = ComputeModifiedUtf8Hash(descriptor + 1); 3804 component_type.Assign(LookupClass(self, descriptor + 1, component_hash, class_loader.Get())); 3805 if (component_type == nullptr) { 3806 DCHECK(self->IsExceptionPending()); 3807 return nullptr; 3808 } else { 3809 self->ClearException(); 3810 } 3811 } 3812 if (UNLIKELY(component_type->IsPrimitiveVoid())) { 3813 ThrowNoClassDefFoundError("Attempt to create array of void primitive type"); 3814 return nullptr; 3815 } 3816 // See if the component type is already loaded. Array classes are 3817 // always associated with the class loader of their underlying 3818 // element type -- an array of Strings goes with the loader for 3819 // java/lang/String -- so we need to look for it there. (The 3820 // caller should have checked for the existence of the class 3821 // before calling here, but they did so with *their* class loader, 3822 // not the component type's loader.) 3823 // 3824 // If we find it, the caller adds "loader" to the class' initiating 3825 // loader list, which should prevent us from going through this again. 3826 // 3827 // This call is unnecessary if "loader" and "component_type->GetClassLoader()" 3828 // are the same, because our caller (FindClass) just did the 3829 // lookup. (Even if we get this wrong we still have correct behavior, 3830 // because we effectively do this lookup again when we add the new 3831 // class to the hash table --- necessary because of possible races with 3832 // other threads.) 3833 if (class_loader.Get() != component_type->GetClassLoader()) { 3834 ObjPtr<mirror::Class> new_class = 3835 LookupClass(self, descriptor, hash, component_type->GetClassLoader()); 3836 if (new_class != nullptr) { 3837 return new_class.Ptr(); 3838 } 3839 } 3840 3841 // Fill out the fields in the Class. 3842 // 3843 // It is possible to execute some methods against arrays, because 3844 // all arrays are subclasses of java_lang_Object_, so we need to set 3845 // up a vtable. We can just point at the one in java_lang_Object_. 3846 // 3847 // Array classes are simple enough that we don't need to do a full 3848 // link step. 3849 auto new_class = hs.NewHandle<mirror::Class>(nullptr); 3850 if (UNLIKELY(!init_done_)) { 3851 // Classes that were hand created, ie not by FindSystemClass 3852 if (strcmp(descriptor, "[Ljava/lang/Class;") == 0) { 3853 new_class.Assign(GetClassRoot(kClassArrayClass)); 3854 } else if (strcmp(descriptor, "[Ljava/lang/Object;") == 0) { 3855 new_class.Assign(GetClassRoot(kObjectArrayClass)); 3856 } else if (strcmp(descriptor, GetClassRootDescriptor(kJavaLangStringArrayClass)) == 0) { 3857 new_class.Assign(GetClassRoot(kJavaLangStringArrayClass)); 3858 } else if (strcmp(descriptor, "[C") == 0) { 3859 new_class.Assign(GetClassRoot(kCharArrayClass)); 3860 } else if (strcmp(descriptor, "[I") == 0) { 3861 new_class.Assign(GetClassRoot(kIntArrayClass)); 3862 } else if (strcmp(descriptor, "[J") == 0) { 3863 new_class.Assign(GetClassRoot(kLongArrayClass)); 3864 } 3865 } 3866 if (new_class == nullptr) { 3867 new_class.Assign(AllocClass(self, mirror::Array::ClassSize(image_pointer_size_))); 3868 if (new_class == nullptr) { 3869 self->AssertPendingOOMException(); 3870 return nullptr; 3871 } 3872 new_class->SetComponentType(component_type.Get()); 3873 } 3874 ObjectLock<mirror::Class> lock(self, new_class); // Must hold lock on object when initializing. 3875 DCHECK(new_class->GetComponentType() != nullptr); 3876 ObjPtr<mirror::Class> java_lang_Object = GetClassRoot(kJavaLangObject); 3877 new_class->SetSuperClass(java_lang_Object); 3878 new_class->SetVTable(java_lang_Object->GetVTable()); 3879 new_class->SetPrimitiveType(Primitive::kPrimNot); 3880 new_class->SetClassLoader(component_type->GetClassLoader()); 3881 if (component_type->IsPrimitive()) { 3882 new_class->SetClassFlags(mirror::kClassFlagNoReferenceFields); 3883 } else { 3884 new_class->SetClassFlags(mirror::kClassFlagObjectArray); 3885 } 3886 mirror::Class::SetStatus(new_class, mirror::Class::kStatusLoaded, self); 3887 new_class->PopulateEmbeddedVTable(image_pointer_size_); 3888 ImTable* object_imt = java_lang_Object->GetImt(image_pointer_size_); 3889 new_class->SetImt(object_imt, image_pointer_size_); 3890 mirror::Class::SetStatus(new_class, mirror::Class::kStatusInitialized, self); 3891 // don't need to set new_class->SetObjectSize(..) 3892 // because Object::SizeOf delegates to Array::SizeOf 3893 3894 // All arrays have java/lang/Cloneable and java/io/Serializable as 3895 // interfaces. We need to set that up here, so that stuff like 3896 // "instanceof" works right. 3897 // 3898 // Note: The GC could run during the call to FindSystemClass, 3899 // so we need to make sure the class object is GC-valid while we're in 3900 // there. Do this by clearing the interface list so the GC will just 3901 // think that the entries are null. 3902 3903 3904 // Use the single, global copies of "interfaces" and "iftable" 3905 // (remember not to free them for arrays). 3906 { 3907 ObjPtr<mirror::IfTable> array_iftable = array_iftable_.Read(); 3908 CHECK(array_iftable != nullptr); 3909 new_class->SetIfTable(array_iftable); 3910 } 3911 3912 // Inherit access flags from the component type. 3913 int access_flags = new_class->GetComponentType()->GetAccessFlags(); 3914 // Lose any implementation detail flags; in particular, arrays aren't finalizable. 3915 access_flags &= kAccJavaFlagsMask; 3916 // Arrays can't be used as a superclass or interface, so we want to add "abstract final" 3917 // and remove "interface". 3918 access_flags |= kAccAbstract | kAccFinal; 3919 access_flags &= ~kAccInterface; 3920 3921 new_class->SetAccessFlags(access_flags); 3922 3923 ObjPtr<mirror::Class> existing = InsertClass(descriptor, new_class.Get(), hash); 3924 if (existing == nullptr) { 3925 // We postpone ClassLoad and ClassPrepare events to this point in time to avoid 3926 // duplicate events in case of races. Array classes don't really follow dedicated 3927 // load and prepare, anyways. 3928 Runtime::Current()->GetRuntimeCallbacks()->ClassLoad(new_class); 3929 Runtime::Current()->GetRuntimeCallbacks()->ClassPrepare(new_class, new_class); 3930 3931 jit::Jit::NewTypeLoadedIfUsingJit(new_class.Get()); 3932 return new_class.Get(); 3933 } 3934 // Another thread must have loaded the class after we 3935 // started but before we finished. Abandon what we've 3936 // done. 3937 // 3938 // (Yes, this happens.) 3939 3940 return existing.Ptr(); 3941 } 3942 3943 mirror::Class* ClassLinker::FindPrimitiveClass(char type) { 3944 switch (type) { 3945 case 'B': 3946 return GetClassRoot(kPrimitiveByte); 3947 case 'C': 3948 return GetClassRoot(kPrimitiveChar); 3949 case 'D': 3950 return GetClassRoot(kPrimitiveDouble); 3951 case 'F': 3952 return GetClassRoot(kPrimitiveFloat); 3953 case 'I': 3954 return GetClassRoot(kPrimitiveInt); 3955 case 'J': 3956 return GetClassRoot(kPrimitiveLong); 3957 case 'S': 3958 return GetClassRoot(kPrimitiveShort); 3959 case 'Z': 3960 return GetClassRoot(kPrimitiveBoolean); 3961 case 'V': 3962 return GetClassRoot(kPrimitiveVoid); 3963 default: 3964 break; 3965 } 3966 std::string printable_type(PrintableChar(type)); 3967 ThrowNoClassDefFoundError("Not a primitive type: %s", printable_type.c_str()); 3968 return nullptr; 3969 } 3970 3971 mirror::Class* ClassLinker::InsertClass(const char* descriptor, ObjPtr<mirror::Class> klass, size_t hash) { 3972 if (VLOG_IS_ON(class_linker)) { 3973 ObjPtr<mirror::DexCache> dex_cache = klass->GetDexCache(); 3974 std::string source; 3975 if (dex_cache != nullptr) { 3976 source += " from "; 3977 source += dex_cache->GetLocation()->ToModifiedUtf8(); 3978 } 3979 LOG(INFO) << "Loaded class " << descriptor << source; 3980 } 3981 { 3982 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 3983 ObjPtr<mirror::ClassLoader> const class_loader = klass->GetClassLoader(); 3984 ClassTable* const class_table = InsertClassTableForClassLoader(class_loader); 3985 ObjPtr<mirror::Class> existing = class_table->Lookup(descriptor, hash); 3986 if (existing != nullptr) { 3987 return existing.Ptr(); 3988 } 3989 VerifyObject(klass); 3990 class_table->InsertWithHash(klass, hash); 3991 if (class_loader != nullptr) { 3992 // This is necessary because we need to have the card dirtied for remembered sets. 3993 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(class_loader); 3994 } 3995 if (log_new_roots_) { 3996 new_class_roots_.push_back(GcRoot<mirror::Class>(klass)); 3997 } 3998 } 3999 if (kIsDebugBuild) { 4000 // Test that copied methods correctly can find their holder. 4001 for (ArtMethod& method : klass->GetCopiedMethods(image_pointer_size_)) { 4002 CHECK_EQ(GetHoldingClassOfCopiedMethod(&method), klass); 4003 } 4004 } 4005 return nullptr; 4006 } 4007 4008 void ClassLinker::WriteBarrierForBootOatFileBssRoots(const OatFile* oat_file) { 4009 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 4010 DCHECK(!oat_file->GetBssGcRoots().empty()) << oat_file->GetLocation(); 4011 if (log_new_roots_ && !ContainsElement(new_bss_roots_boot_oat_files_, oat_file)) { 4012 new_bss_roots_boot_oat_files_.push_back(oat_file); 4013 } 4014 } 4015 4016 // TODO This should really be in mirror::Class. 4017 void ClassLinker::UpdateClassMethods(ObjPtr<mirror::Class> klass, 4018 LengthPrefixedArray<ArtMethod>* new_methods) { 4019 klass->SetMethodsPtrUnchecked(new_methods, 4020 klass->NumDirectMethods(), 4021 klass->NumDeclaredVirtualMethods()); 4022 // Need to mark the card so that the remembered sets and mod union tables get updated. 4023 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(klass); 4024 } 4025 4026 mirror::Class* ClassLinker::LookupClass(Thread* self, 4027 const char* descriptor, 4028 ObjPtr<mirror::ClassLoader> class_loader) { 4029 return LookupClass(self, descriptor, ComputeModifiedUtf8Hash(descriptor), class_loader); 4030 } 4031 4032 mirror::Class* ClassLinker::LookupClass(Thread* self, 4033 const char* descriptor, 4034 size_t hash, 4035 ObjPtr<mirror::ClassLoader> class_loader) { 4036 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 4037 ClassTable* const class_table = ClassTableForClassLoader(class_loader); 4038 if (class_table != nullptr) { 4039 ObjPtr<mirror::Class> result = class_table->Lookup(descriptor, hash); 4040 if (result != nullptr) { 4041 return result.Ptr(); 4042 } 4043 } 4044 return nullptr; 4045 } 4046 4047 class MoveClassTableToPreZygoteVisitor : public ClassLoaderVisitor { 4048 public: 4049 explicit MoveClassTableToPreZygoteVisitor() {} 4050 4051 void Visit(ObjPtr<mirror::ClassLoader> class_loader) 4052 REQUIRES(Locks::classlinker_classes_lock_) 4053 REQUIRES_SHARED(Locks::mutator_lock_) OVERRIDE { 4054 ClassTable* const class_table = class_loader->GetClassTable(); 4055 if (class_table != nullptr) { 4056 class_table->FreezeSnapshot(); 4057 } 4058 } 4059 }; 4060 4061 void ClassLinker::MoveClassTableToPreZygote() { 4062 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 4063 boot_class_table_->FreezeSnapshot(); 4064 MoveClassTableToPreZygoteVisitor visitor; 4065 VisitClassLoaders(&visitor); 4066 } 4067 4068 // Look up classes by hash and descriptor and put all matching ones in the result array. 4069 class LookupClassesVisitor : public ClassLoaderVisitor { 4070 public: 4071 LookupClassesVisitor(const char* descriptor, 4072 size_t hash, 4073 std::vector<ObjPtr<mirror::Class>>* result) 4074 : descriptor_(descriptor), 4075 hash_(hash), 4076 result_(result) {} 4077 4078 void Visit(ObjPtr<mirror::ClassLoader> class_loader) 4079 REQUIRES_SHARED(Locks::classlinker_classes_lock_, Locks::mutator_lock_) OVERRIDE { 4080 ClassTable* const class_table = class_loader->GetClassTable(); 4081 ObjPtr<mirror::Class> klass = class_table->Lookup(descriptor_, hash_); 4082 // Add `klass` only if `class_loader` is its defining (not just initiating) class loader. 4083 if (klass != nullptr && klass->GetClassLoader() == class_loader) { 4084 result_->push_back(klass); 4085 } 4086 } 4087 4088 private: 4089 const char* const descriptor_; 4090 const size_t hash_; 4091 std::vector<ObjPtr<mirror::Class>>* const result_; 4092 }; 4093 4094 void ClassLinker::LookupClasses(const char* descriptor, 4095 std::vector<ObjPtr<mirror::Class>>& result) { 4096 result.clear(); 4097 Thread* const self = Thread::Current(); 4098 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); 4099 const size_t hash = ComputeModifiedUtf8Hash(descriptor); 4100 ObjPtr<mirror::Class> klass = boot_class_table_->Lookup(descriptor, hash); 4101 if (klass != nullptr) { 4102 DCHECK(klass->GetClassLoader() == nullptr); 4103 result.push_back(klass); 4104 } 4105 LookupClassesVisitor visitor(descriptor, hash, &result); 4106 VisitClassLoaders(&visitor); 4107 } 4108 4109 bool ClassLinker::AttemptSupertypeVerification(Thread* self, 4110 Handle<mirror::Class> klass, 4111 Handle<mirror::Class> supertype) { 4112 DCHECK(self != nullptr); 4113 DCHECK(klass != nullptr); 4114 DCHECK(supertype != nullptr); 4115 4116 if (!supertype->IsVerified() && !supertype->IsErroneous()) { 4117 VerifyClass(self, supertype); 4118 } 4119 4120 if (supertype->IsVerified() || supertype->ShouldVerifyAtRuntime()) { 4121 // The supertype is either verified, or we soft failed at AOT time. 4122 DCHECK(supertype->IsVerified() || Runtime::Current()->IsAotCompiler()); 4123 return true; 4124 } 4125 // If we got this far then we have a hard failure. 4126 std::string error_msg = 4127 StringPrintf("Rejecting class %s that attempts to sub-type erroneous class %s", 4128 klass->PrettyDescriptor().c_str(), 4129 supertype->PrettyDescriptor().c_str()); 4130 LOG(WARNING) << error_msg << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8(); 4131 StackHandleScope<1> hs(self); 4132 Handle<mirror::Throwable> cause(hs.NewHandle(self->GetException())); 4133 if (cause != nullptr) { 4134 // Set during VerifyClass call (if at all). 4135 self->ClearException(); 4136 } 4137 // Change into a verify error. 4138 ThrowVerifyError(klass.Get(), "%s", error_msg.c_str()); 4139 if (cause != nullptr) { 4140 self->GetException()->SetCause(cause.Get()); 4141 } 4142 ClassReference ref(klass->GetDexCache()->GetDexFile(), klass->GetDexClassDefIndex()); 4143 if (Runtime::Current()->IsAotCompiler()) { 4144 Runtime::Current()->GetCompilerCallbacks()->ClassRejected(ref); 4145 } 4146 // Need to grab the lock to change status. 4147 ObjectLock<mirror::Class> super_lock(self, klass); 4148 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorResolved, self); 4149 return false; 4150 } 4151 4152 // Ensures that methods have the kAccSkipAccessChecks bit set. We use the 4153 // kAccVerificationAttempted bit on the class access flags to determine whether this has been done 4154 // before. 4155 static void EnsureSkipAccessChecksMethods(Handle<mirror::Class> klass, PointerSize pointer_size) 4156 REQUIRES_SHARED(Locks::mutator_lock_) { 4157 if (!klass->WasVerificationAttempted()) { 4158 klass->SetSkipAccessChecksFlagOnAllMethods(pointer_size); 4159 klass->SetVerificationAttempted(); 4160 } 4161 } 4162 4163 verifier::FailureKind ClassLinker::VerifyClass( 4164 Thread* self, Handle<mirror::Class> klass, verifier::HardFailLogMode log_level) { 4165 { 4166 // TODO: assert that the monitor on the Class is held 4167 ObjectLock<mirror::Class> lock(self, klass); 4168 4169 // Is somebody verifying this now? 4170 mirror::Class::Status old_status = klass->GetStatus(); 4171 while (old_status == mirror::Class::kStatusVerifying || 4172 old_status == mirror::Class::kStatusVerifyingAtRuntime) { 4173 lock.WaitIgnoringInterrupts(); 4174 // WaitIgnoringInterrupts can still receive an interrupt and return early, in this 4175 // case we may see the same status again. b/62912904. This is why the check is 4176 // greater or equal. 4177 CHECK(klass->IsErroneous() || (klass->GetStatus() >= old_status)) 4178 << "Class '" << klass->PrettyClass() 4179 << "' performed an illegal verification state transition from " << old_status 4180 << " to " << klass->GetStatus(); 4181 old_status = klass->GetStatus(); 4182 } 4183 4184 // The class might already be erroneous, for example at compile time if we attempted to verify 4185 // this class as a parent to another. 4186 if (klass->IsErroneous()) { 4187 ThrowEarlierClassFailure(klass.Get()); 4188 return verifier::FailureKind::kHardFailure; 4189 } 4190 4191 // Don't attempt to re-verify if already verified. 4192 if (klass->IsVerified()) { 4193 EnsureSkipAccessChecksMethods(klass, image_pointer_size_); 4194 return verifier::FailureKind::kNoFailure; 4195 } 4196 4197 // For AOT, don't attempt to re-verify if we have already found we should 4198 // verify at runtime. 4199 if (Runtime::Current()->IsAotCompiler() && klass->ShouldVerifyAtRuntime()) { 4200 return verifier::FailureKind::kSoftFailure; 4201 } 4202 4203 if (klass->GetStatus() == mirror::Class::kStatusResolved) { 4204 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerifying, self); 4205 } else { 4206 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime) 4207 << klass->PrettyClass(); 4208 CHECK(!Runtime::Current()->IsAotCompiler()); 4209 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerifyingAtRuntime, self); 4210 } 4211 4212 // Skip verification if disabled. 4213 if (!Runtime::Current()->IsVerificationEnabled()) { 4214 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self); 4215 EnsureSkipAccessChecksMethods(klass, image_pointer_size_); 4216 return verifier::FailureKind::kNoFailure; 4217 } 4218 } 4219 4220 VLOG(class_linker) << "Beginning verification for class: " 4221 << klass->PrettyDescriptor() 4222 << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8(); 4223 4224 // Verify super class. 4225 StackHandleScope<2> hs(self); 4226 MutableHandle<mirror::Class> supertype(hs.NewHandle(klass->GetSuperClass())); 4227 // If we have a superclass and we get a hard verification failure we can return immediately. 4228 if (supertype != nullptr && !AttemptSupertypeVerification(self, klass, supertype)) { 4229 CHECK(self->IsExceptionPending()) << "Verification error should be pending."; 4230 return verifier::FailureKind::kHardFailure; 4231 } 4232 4233 // Verify all default super-interfaces. 4234 // 4235 // (1) Don't bother if the superclass has already had a soft verification failure. 4236 // 4237 // (2) Interfaces shouldn't bother to do this recursive verification because they cannot cause 4238 // recursive initialization by themselves. This is because when an interface is initialized 4239 // directly it must not initialize its superinterfaces. We are allowed to verify regardless 4240 // but choose not to for an optimization. If the interfaces is being verified due to a class 4241 // initialization (which would need all the default interfaces to be verified) the class code 4242 // will trigger the recursive verification anyway. 4243 if ((supertype == nullptr || supertype->IsVerified()) // See (1) 4244 && !klass->IsInterface()) { // See (2) 4245 int32_t iftable_count = klass->GetIfTableCount(); 4246 MutableHandle<mirror::Class> iface(hs.NewHandle<mirror::Class>(nullptr)); 4247 // Loop through all interfaces this class has defined. It doesn't matter the order. 4248 for (int32_t i = 0; i < iftable_count; i++) { 4249 iface.Assign(klass->GetIfTable()->GetInterface(i)); 4250 DCHECK(iface != nullptr); 4251 // We only care if we have default interfaces and can skip if we are already verified... 4252 if (LIKELY(!iface->HasDefaultMethods() || iface->IsVerified())) { 4253 continue; 4254 } else if (UNLIKELY(!AttemptSupertypeVerification(self, klass, iface))) { 4255 // We had a hard failure while verifying this interface. Just return immediately. 4256 CHECK(self->IsExceptionPending()) << "Verification error should be pending."; 4257 return verifier::FailureKind::kHardFailure; 4258 } else if (UNLIKELY(!iface->IsVerified())) { 4259 // We softly failed to verify the iface. Stop checking and clean up. 4260 // Put the iface into the supertype handle so we know what caused us to fail. 4261 supertype.Assign(iface.Get()); 4262 break; 4263 } 4264 } 4265 } 4266 4267 // At this point if verification failed, then supertype is the "first" supertype that failed 4268 // verification (without a specific order). If verification succeeded, then supertype is either 4269 // null or the original superclass of klass and is verified. 4270 DCHECK(supertype == nullptr || 4271 supertype.Get() == klass->GetSuperClass() || 4272 !supertype->IsVerified()); 4273 4274 // Try to use verification information from the oat file, otherwise do runtime verification. 4275 const DexFile& dex_file = *klass->GetDexCache()->GetDexFile(); 4276 mirror::Class::Status oat_file_class_status(mirror::Class::kStatusNotReady); 4277 bool preverified = VerifyClassUsingOatFile(dex_file, klass.Get(), oat_file_class_status); 4278 4279 VLOG(class_linker) << "Class preverified status for class " 4280 << klass->PrettyDescriptor() 4281 << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8() 4282 << ": " 4283 << preverified; 4284 4285 // If the oat file says the class had an error, re-run the verifier. That way we will get a 4286 // precise error message. To ensure a rerun, test: 4287 // mirror::Class::IsErroneous(oat_file_class_status) => !preverified 4288 DCHECK(!mirror::Class::IsErroneous(oat_file_class_status) || !preverified); 4289 4290 std::string error_msg; 4291 verifier::FailureKind verifier_failure = verifier::FailureKind::kNoFailure; 4292 if (!preverified) { 4293 verifier_failure = PerformClassVerification(self, klass, log_level, &error_msg); 4294 } 4295 4296 // Verification is done, grab the lock again. 4297 ObjectLock<mirror::Class> lock(self, klass); 4298 4299 if (preverified || verifier_failure != verifier::FailureKind::kHardFailure) { 4300 if (!preverified && verifier_failure != verifier::FailureKind::kNoFailure) { 4301 VLOG(class_linker) << "Soft verification failure in class " 4302 << klass->PrettyDescriptor() 4303 << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8() 4304 << " because: " << error_msg; 4305 } 4306 self->AssertNoPendingException(); 4307 // Make sure all classes referenced by catch blocks are resolved. 4308 ResolveClassExceptionHandlerTypes(klass); 4309 if (verifier_failure == verifier::FailureKind::kNoFailure) { 4310 // Even though there were no verifier failures we need to respect whether the super-class and 4311 // super-default-interfaces were verified or requiring runtime reverification. 4312 if (supertype == nullptr || supertype->IsVerified()) { 4313 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self); 4314 } else { 4315 CHECK_EQ(supertype->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime); 4316 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetryVerificationAtRuntime, self); 4317 // Pretend a soft failure occurred so that we don't consider the class verified below. 4318 verifier_failure = verifier::FailureKind::kSoftFailure; 4319 } 4320 } else { 4321 CHECK_EQ(verifier_failure, verifier::FailureKind::kSoftFailure); 4322 // Soft failures at compile time should be retried at runtime. Soft 4323 // failures at runtime will be handled by slow paths in the generated 4324 // code. Set status accordingly. 4325 if (Runtime::Current()->IsAotCompiler()) { 4326 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetryVerificationAtRuntime, self); 4327 } else { 4328 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self); 4329 // As this is a fake verified status, make sure the methods are _not_ marked 4330 // kAccSkipAccessChecks later. 4331 klass->SetVerificationAttempted(); 4332 } 4333 } 4334 } else { 4335 VLOG(verifier) << "Verification failed on class " << klass->PrettyDescriptor() 4336 << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8() 4337 << " because: " << error_msg; 4338 self->AssertNoPendingException(); 4339 ThrowVerifyError(klass.Get(), "%s", error_msg.c_str()); 4340 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorResolved, self); 4341 } 4342 if (preverified || verifier_failure == verifier::FailureKind::kNoFailure) { 4343 // Class is verified so we don't need to do any access check on its methods. 4344 // Let the interpreter know it by setting the kAccSkipAccessChecks flag onto each 4345 // method. 4346 // Note: we're going here during compilation and at runtime. When we set the 4347 // kAccSkipAccessChecks flag when compiling image classes, the flag is recorded 4348 // in the image and is set when loading the image. 4349 4350 if (UNLIKELY(Runtime::Current()->IsVerificationSoftFail())) { 4351 // Never skip access checks if the verification soft fail is forced. 4352 // Mark the class as having a verification attempt to avoid re-running the verifier. 4353 klass->SetVerificationAttempted(); 4354 } else { 4355 EnsureSkipAccessChecksMethods(klass, image_pointer_size_); 4356 } 4357 } 4358 return verifier_failure; 4359 } 4360 4361 verifier::FailureKind ClassLinker::PerformClassVerification(Thread* self, 4362 Handle<mirror::Class> klass, 4363 verifier::HardFailLogMode log_level, 4364 std::string* error_msg) { 4365 Runtime* const runtime = Runtime::Current(); 4366 return verifier::MethodVerifier::VerifyClass(self, 4367 klass.Get(), 4368 runtime->GetCompilerCallbacks(), 4369 runtime->IsAotCompiler(), 4370 log_level, 4371 error_msg); 4372 } 4373 4374 bool ClassLinker::VerifyClassUsingOatFile(const DexFile& dex_file, 4375 ObjPtr<mirror::Class> klass, 4376 mirror::Class::Status& oat_file_class_status) { 4377 // If we're compiling, we can only verify the class using the oat file if 4378 // we are not compiling the image or if the class we're verifying is not part of 4379 // the app. In other words, we will only check for preverification of bootclasspath 4380 // classes. 4381 if (Runtime::Current()->IsAotCompiler()) { 4382 // Are we compiling the bootclasspath? 4383 if (Runtime::Current()->GetCompilerCallbacks()->IsBootImage()) { 4384 return false; 4385 } 4386 // We are compiling an app (not the image). 4387 4388 // Is this an app class? (I.e. not a bootclasspath class) 4389 if (klass->GetClassLoader() != nullptr) { 4390 return false; 4391 } 4392 } 4393 4394 const OatFile::OatDexFile* oat_dex_file = dex_file.GetOatDexFile(); 4395 // In case we run without an image there won't be a backing oat file. 4396 if (oat_dex_file == nullptr || oat_dex_file->GetOatFile() == nullptr) { 4397 return false; 4398 } 4399 4400 uint16_t class_def_index = klass->GetDexClassDefIndex(); 4401 oat_file_class_status = oat_dex_file->GetOatClass(class_def_index).GetStatus(); 4402 if (oat_file_class_status >= mirror::Class::kStatusVerified) { 4403 return true; 4404 } 4405 // If we only verified a subset of the classes at compile time, we can end up with classes that 4406 // were resolved by the verifier. 4407 if (oat_file_class_status == mirror::Class::kStatusResolved) { 4408 return false; 4409 } 4410 if (oat_file_class_status == mirror::Class::kStatusRetryVerificationAtRuntime) { 4411 // Compile time verification failed with a soft error. Compile time verification can fail 4412 // because we have incomplete type information. Consider the following: 4413 // class ... { 4414 // Foo x; 4415 // .... () { 4416 // if (...) { 4417 // v1 gets assigned a type of resolved class Foo 4418 // } else { 4419 // v1 gets assigned a type of unresolved class Bar 4420 // } 4421 // iput x = v1 4422 // } } 4423 // when we merge v1 following the if-the-else it results in Conflict 4424 // (see verifier::RegType::Merge) as we can't know the type of Bar and we could possibly be 4425 // allowing an unsafe assignment to the field x in the iput (javac may have compiled this as 4426 // it knew Bar was a sub-class of Foo, but for us this may have been moved into a separate apk 4427 // at compile time). 4428 return false; 4429 } 4430 if (mirror::Class::IsErroneous(oat_file_class_status)) { 4431 // Compile time verification failed with a hard error. This is caused by invalid instructions 4432 // in the class. These errors are unrecoverable. 4433 return false; 4434 } 4435 if (oat_file_class_status == mirror::Class::kStatusNotReady) { 4436 // Status is uninitialized if we couldn't determine the status at compile time, for example, 4437 // not loading the class. 4438 // TODO: when the verifier doesn't rely on Class-es failing to resolve/load the type hierarchy 4439 // isn't a problem and this case shouldn't occur 4440 return false; 4441 } 4442 std::string temp; 4443 LOG(FATAL) << "Unexpected class status: " << oat_file_class_status 4444 << " " << dex_file.GetLocation() << " " << klass->PrettyClass() << " " 4445 << klass->GetDescriptor(&temp); 4446 UNREACHABLE(); 4447 } 4448 4449 void ClassLinker::ResolveClassExceptionHandlerTypes(Handle<mirror::Class> klass) { 4450 for (ArtMethod& method : klass->GetMethods(image_pointer_size_)) { 4451 ResolveMethodExceptionHandlerTypes(&method); 4452 } 4453 } 4454 4455 void ClassLinker::ResolveMethodExceptionHandlerTypes(ArtMethod* method) { 4456 // similar to DexVerifier::ScanTryCatchBlocks and dex2oat's ResolveExceptionsForMethod. 4457 const DexFile::CodeItem* code_item = 4458 method->GetDexFile()->GetCodeItem(method->GetCodeItemOffset()); 4459 if (code_item == nullptr) { 4460 return; // native or abstract method 4461 } 4462 if (code_item->tries_size_ == 0) { 4463 return; // nothing to process 4464 } 4465 const uint8_t* handlers_ptr = DexFile::GetCatchHandlerData(*code_item, 0); 4466 uint32_t handlers_size = DecodeUnsignedLeb128(&handlers_ptr); 4467 for (uint32_t idx = 0; idx < handlers_size; idx++) { 4468 CatchHandlerIterator iterator(handlers_ptr); 4469 for (; iterator.HasNext(); iterator.Next()) { 4470 // Ensure exception types are resolved so that they don't need resolution to be delivered, 4471 // unresolved exception types will be ignored by exception delivery 4472 if (iterator.GetHandlerTypeIndex().IsValid()) { 4473 ObjPtr<mirror::Class> exception_type = ResolveType(iterator.GetHandlerTypeIndex(), method); 4474 if (exception_type == nullptr) { 4475 DCHECK(Thread::Current()->IsExceptionPending()); 4476 Thread::Current()->ClearException(); 4477 } 4478 } 4479 } 4480 handlers_ptr = iterator.EndDataPointer(); 4481 } 4482 } 4483 4484 mirror::Class* ClassLinker::CreateProxyClass(ScopedObjectAccessAlreadyRunnable& soa, 4485 jstring name, 4486 jobjectArray interfaces, 4487 jobject loader, 4488 jobjectArray methods, 4489 jobjectArray throws) { 4490 Thread* self = soa.Self(); 4491 StackHandleScope<10> hs(self); 4492 MutableHandle<mirror::Class> temp_klass(hs.NewHandle( 4493 AllocClass(self, GetClassRoot(kJavaLangClass), sizeof(mirror::Class)))); 4494 if (temp_klass == nullptr) { 4495 CHECK(self->IsExceptionPending()); // OOME. 4496 return nullptr; 4497 } 4498 DCHECK(temp_klass->GetClass() != nullptr); 4499 temp_klass->SetObjectSize(sizeof(mirror::Proxy)); 4500 // Set the class access flags incl. VerificationAttempted, so we do not try to set the flag on 4501 // the methods. 4502 temp_klass->SetAccessFlags(kAccClassIsProxy | kAccPublic | kAccFinal | kAccVerificationAttempted); 4503 temp_klass->SetClassLoader(soa.Decode<mirror::ClassLoader>(loader)); 4504 DCHECK_EQ(temp_klass->GetPrimitiveType(), Primitive::kPrimNot); 4505 temp_klass->SetName(soa.Decode<mirror::String>(name)); 4506 temp_klass->SetDexCache(GetClassRoot(kJavaLangReflectProxy)->GetDexCache()); 4507 // Object has an empty iftable, copy it for that reason. 4508 temp_klass->SetIfTable(GetClassRoot(kJavaLangObject)->GetIfTable()); 4509 mirror::Class::SetStatus(temp_klass, mirror::Class::kStatusIdx, self); 4510 std::string descriptor(GetDescriptorForProxy(temp_klass.Get())); 4511 const size_t hash = ComputeModifiedUtf8Hash(descriptor.c_str()); 4512 4513 // Needs to be before we insert the class so that the allocator field is set. 4514 LinearAlloc* const allocator = GetOrCreateAllocatorForClassLoader(temp_klass->GetClassLoader()); 4515 4516 // Insert the class before loading the fields as the field roots 4517 // (ArtField::declaring_class_) are only visited from the class 4518 // table. There can't be any suspend points between inserting the 4519 // class and setting the field arrays below. 4520 ObjPtr<mirror::Class> existing = InsertClass(descriptor.c_str(), temp_klass.Get(), hash); 4521 CHECK(existing == nullptr); 4522 4523 // Instance fields are inherited, but we add a couple of static fields... 4524 const size_t num_fields = 2; 4525 LengthPrefixedArray<ArtField>* sfields = AllocArtFieldArray(self, allocator, num_fields); 4526 temp_klass->SetSFieldsPtr(sfields); 4527 4528 // 1. Create a static field 'interfaces' that holds the _declared_ interfaces implemented by 4529 // our proxy, so Class.getInterfaces doesn't return the flattened set. 4530 ArtField& interfaces_sfield = sfields->At(0); 4531 interfaces_sfield.SetDexFieldIndex(0); 4532 interfaces_sfield.SetDeclaringClass(temp_klass.Get()); 4533 interfaces_sfield.SetAccessFlags(kAccStatic | kAccPublic | kAccFinal); 4534 4535 // 2. Create a static field 'throws' that holds exceptions thrown by our methods. 4536 ArtField& throws_sfield = sfields->At(1); 4537 throws_sfield.SetDexFieldIndex(1); 4538 throws_sfield.SetDeclaringClass(temp_klass.Get()); 4539 throws_sfield.SetAccessFlags(kAccStatic | kAccPublic | kAccFinal); 4540 4541 // Proxies have 1 direct method, the constructor 4542 const size_t num_direct_methods = 1; 4543 4544 // They have as many virtual methods as the array 4545 auto h_methods = hs.NewHandle(soa.Decode<mirror::ObjectArray<mirror::Method>>(methods)); 4546 DCHECK_EQ(h_methods->GetClass(), mirror::Method::ArrayClass()) 4547 << mirror::Class::PrettyClass(h_methods->GetClass()); 4548 const size_t num_virtual_methods = h_methods->GetLength(); 4549 4550 // Create the methods array. 4551 LengthPrefixedArray<ArtMethod>* proxy_class_methods = AllocArtMethodArray( 4552 self, allocator, num_direct_methods + num_virtual_methods); 4553 // Currently AllocArtMethodArray cannot return null, but the OOM logic is left there in case we 4554 // want to throw OOM in the future. 4555 if (UNLIKELY(proxy_class_methods == nullptr)) { 4556 self->AssertPendingOOMException(); 4557 return nullptr; 4558 } 4559 temp_klass->SetMethodsPtr(proxy_class_methods, num_direct_methods, num_virtual_methods); 4560 4561 // Create the single direct method. 4562 CreateProxyConstructor(temp_klass, temp_klass->GetDirectMethodUnchecked(0, image_pointer_size_)); 4563 4564 // Create virtual method using specified prototypes. 4565 // TODO These should really use the iterators. 4566 for (size_t i = 0; i < num_virtual_methods; ++i) { 4567 auto* virtual_method = temp_klass->GetVirtualMethodUnchecked(i, image_pointer_size_); 4568 auto* prototype = h_methods->Get(i)->GetArtMethod(); 4569 CreateProxyMethod(temp_klass, prototype, virtual_method); 4570 DCHECK(virtual_method->GetDeclaringClass() != nullptr); 4571 DCHECK(prototype->GetDeclaringClass() != nullptr); 4572 } 4573 4574 // The super class is java.lang.reflect.Proxy 4575 temp_klass->SetSuperClass(GetClassRoot(kJavaLangReflectProxy)); 4576 // Now effectively in the loaded state. 4577 mirror::Class::SetStatus(temp_klass, mirror::Class::kStatusLoaded, self); 4578 self->AssertNoPendingException(); 4579 4580 // At this point the class is loaded. Publish a ClassLoad event. 4581 // Note: this may be a temporary class. It is a listener's responsibility to handle this. 4582 Runtime::Current()->GetRuntimeCallbacks()->ClassLoad(temp_klass); 4583 4584 MutableHandle<mirror::Class> klass = hs.NewHandle<mirror::Class>(nullptr); 4585 { 4586 // Must hold lock on object when resolved. 4587 ObjectLock<mirror::Class> resolution_lock(self, temp_klass); 4588 // Link the fields and virtual methods, creating vtable and iftables. 4589 // The new class will replace the old one in the class table. 4590 Handle<mirror::ObjectArray<mirror::Class>> h_interfaces( 4591 hs.NewHandle(soa.Decode<mirror::ObjectArray<mirror::Class>>(interfaces))); 4592 if (!LinkClass(self, descriptor.c_str(), temp_klass, h_interfaces, &klass)) { 4593 mirror::Class::SetStatus(temp_klass, mirror::Class::kStatusErrorUnresolved, self); 4594 return nullptr; 4595 } 4596 } 4597 CHECK(temp_klass->IsRetired()); 4598 CHECK_NE(temp_klass.Get(), klass.Get()); 4599 4600 CHECK_EQ(interfaces_sfield.GetDeclaringClass(), klass.Get()); 4601 interfaces_sfield.SetObject<false>( 4602 klass.Get(), 4603 soa.Decode<mirror::ObjectArray<mirror::Class>>(interfaces)); 4604 CHECK_EQ(throws_sfield.GetDeclaringClass(), klass.Get()); 4605 throws_sfield.SetObject<false>( 4606 klass.Get(), 4607 soa.Decode<mirror::ObjectArray<mirror::ObjectArray<mirror::Class>>>(throws)); 4608 4609 Runtime::Current()->GetRuntimeCallbacks()->ClassPrepare(temp_klass, klass); 4610 4611 { 4612 // Lock on klass is released. Lock new class object. 4613 ObjectLock<mirror::Class> initialization_lock(self, klass); 4614 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitialized, self); 4615 } 4616 4617 // sanity checks 4618 if (kIsDebugBuild) { 4619 CHECK(klass->GetIFieldsPtr() == nullptr); 4620 CheckProxyConstructor(klass->GetDirectMethod(0, image_pointer_size_)); 4621 4622 for (size_t i = 0; i < num_virtual_methods; ++i) { 4623 auto* virtual_method = klass->GetVirtualMethodUnchecked(i, image_pointer_size_); 4624 auto* prototype = h_methods->Get(i++)->GetArtMethod(); 4625 CheckProxyMethod(virtual_method, prototype); 4626 } 4627 4628 StackHandleScope<1> hs2(self); 4629 Handle<mirror::String> decoded_name = hs2.NewHandle(soa.Decode<mirror::String>(name)); 4630 std::string interfaces_field_name(StringPrintf("java.lang.Class[] %s.interfaces", 4631 decoded_name->ToModifiedUtf8().c_str())); 4632 CHECK_EQ(ArtField::PrettyField(klass->GetStaticField(0)), interfaces_field_name); 4633 4634 std::string throws_field_name(StringPrintf("java.lang.Class[][] %s.throws", 4635 decoded_name->ToModifiedUtf8().c_str())); 4636 CHECK_EQ(ArtField::PrettyField(klass->GetStaticField(1)), throws_field_name); 4637 4638 CHECK_EQ(klass.Get()->GetProxyInterfaces(), 4639 soa.Decode<mirror::ObjectArray<mirror::Class>>(interfaces)); 4640 CHECK_EQ(klass.Get()->GetProxyThrows(), 4641 soa.Decode<mirror::ObjectArray<mirror::ObjectArray<mirror::Class>>>(throws)); 4642 } 4643 return klass.Get(); 4644 } 4645 4646 std::string ClassLinker::GetDescriptorForProxy(ObjPtr<mirror::Class> proxy_class) { 4647 DCHECK(proxy_class->IsProxyClass()); 4648 ObjPtr<mirror::String> name = proxy_class->GetName(); 4649 DCHECK(name != nullptr); 4650 return DotToDescriptor(name->ToModifiedUtf8().c_str()); 4651 } 4652 4653 void ClassLinker::CreateProxyConstructor(Handle<mirror::Class> klass, ArtMethod* out) { 4654 // Create constructor for Proxy that must initialize the method. 4655 CHECK_EQ(GetClassRoot(kJavaLangReflectProxy)->NumDirectMethods(), 23u); 4656 4657 // Find the <init>(InvocationHandler)V method. The exact method offset varies depending 4658 // on which front-end compiler was used to build the libcore DEX files. 4659 ArtMethod* proxy_constructor = GetClassRoot(kJavaLangReflectProxy)->FindConstructor( 4660 "(Ljava/lang/reflect/InvocationHandler;)V", image_pointer_size_); 4661 DCHECK(proxy_constructor != nullptr) 4662 << "Could not find <init> method in java.lang.reflect.Proxy"; 4663 4664 // Ensure constructor is in dex cache so that we can use the dex cache to look up the overridden 4665 // constructor method. 4666 GetClassRoot(kJavaLangReflectProxy)->GetDexCache()->SetResolvedMethod( 4667 proxy_constructor->GetDexMethodIndex(), proxy_constructor, image_pointer_size_); 4668 // Clone the existing constructor of Proxy (our constructor would just invoke it so steal its 4669 // code_ too) 4670 DCHECK(out != nullptr); 4671 out->CopyFrom(proxy_constructor, image_pointer_size_); 4672 // Make this constructor public and fix the class to be our Proxy version. 4673 // Mark kAccCompileDontBother so that we don't take JIT samples for the method. b/62349349 4674 // Note that the compiler calls a ResolveMethod() overload that does not handle a Proxy referrer. 4675 out->SetAccessFlags((out->GetAccessFlags() & ~kAccProtected) | 4676 kAccPublic | 4677 kAccCompileDontBother); 4678 out->SetDeclaringClass(klass.Get()); 4679 } 4680 4681 void ClassLinker::CheckProxyConstructor(ArtMethod* constructor) const { 4682 CHECK(constructor->IsConstructor()); 4683 auto* np = constructor->GetInterfaceMethodIfProxy(image_pointer_size_); 4684 CHECK_STREQ(np->GetName(), "<init>"); 4685 CHECK_STREQ(np->GetSignature().ToString().c_str(), "(Ljava/lang/reflect/InvocationHandler;)V"); 4686 DCHECK(constructor->IsPublic()); 4687 } 4688 4689 void ClassLinker::CreateProxyMethod(Handle<mirror::Class> klass, ArtMethod* prototype, 4690 ArtMethod* out) { 4691 // Ensure prototype is in dex cache so that we can use the dex cache to look up the overridden 4692 // prototype method 4693 auto* dex_cache = prototype->GetDeclaringClass()->GetDexCache(); 4694 // Avoid dirtying the dex cache unless we need to. 4695 if (dex_cache->GetResolvedMethod(prototype->GetDexMethodIndex(), image_pointer_size_) != 4696 prototype) { 4697 dex_cache->SetResolvedMethod( 4698 prototype->GetDexMethodIndex(), prototype, image_pointer_size_); 4699 } 4700 // We steal everything from the prototype (such as DexCache, invoke stub, etc.) then specialize 4701 // as necessary 4702 DCHECK(out != nullptr); 4703 out->CopyFrom(prototype, image_pointer_size_); 4704 4705 // Set class to be the concrete proxy class. 4706 out->SetDeclaringClass(klass.Get()); 4707 // Clear the abstract, default and conflict flags to ensure that defaults aren't picked in 4708 // preference to the invocation handler. 4709 const uint32_t kRemoveFlags = kAccAbstract | kAccDefault | kAccDefaultConflict; 4710 // Make the method final. 4711 // Mark kAccCompileDontBother so that we don't take JIT samples for the method. b/62349349 4712 const uint32_t kAddFlags = kAccFinal | kAccCompileDontBother; 4713 out->SetAccessFlags((out->GetAccessFlags() & ~kRemoveFlags) | kAddFlags); 4714 4715 // Clear the dex_code_item_offset_. It needs to be 0 since proxy methods have no CodeItems but the 4716 // method they copy might (if it's a default method). 4717 out->SetCodeItemOffset(0); 4718 4719 // At runtime the method looks like a reference and argument saving method, clone the code 4720 // related parameters from this method. 4721 out->SetEntryPointFromQuickCompiledCode(GetQuickProxyInvokeHandler()); 4722 } 4723 4724 void ClassLinker::CheckProxyMethod(ArtMethod* method, ArtMethod* prototype) const { 4725 // Basic sanity 4726 CHECK(!prototype->IsFinal()); 4727 CHECK(method->IsFinal()); 4728 CHECK(method->IsInvokable()); 4729 4730 // The proxy method doesn't have its own dex cache or dex file and so it steals those of its 4731 // interface prototype. The exception to this are Constructors and the Class of the Proxy itself. 4732 CHECK(prototype->HasSameDexCacheResolvedMethods(method, image_pointer_size_)); 4733 auto* np = method->GetInterfaceMethodIfProxy(image_pointer_size_); 4734 CHECK_EQ(prototype->GetDeclaringClass()->GetDexCache(), np->GetDexCache()); 4735 CHECK_EQ(prototype->GetDexMethodIndex(), method->GetDexMethodIndex()); 4736 4737 CHECK_STREQ(np->GetName(), prototype->GetName()); 4738 CHECK_STREQ(np->GetShorty(), prototype->GetShorty()); 4739 // More complex sanity - via dex cache 4740 CHECK_EQ(np->GetReturnType(true /* resolve */), prototype->GetReturnType(true /* resolve */)); 4741 } 4742 4743 bool ClassLinker::CanWeInitializeClass(ObjPtr<mirror::Class> klass, bool can_init_statics, 4744 bool can_init_parents) { 4745 if (can_init_statics && can_init_parents) { 4746 return true; 4747 } 4748 if (!can_init_statics) { 4749 // Check if there's a class initializer. 4750 ArtMethod* clinit = klass->FindClassInitializer(image_pointer_size_); 4751 if (clinit != nullptr) { 4752 return false; 4753 } 4754 // Check if there are encoded static values needing initialization. 4755 if (klass->NumStaticFields() != 0) { 4756 const DexFile::ClassDef* dex_class_def = klass->GetClassDef(); 4757 DCHECK(dex_class_def != nullptr); 4758 if (dex_class_def->static_values_off_ != 0) { 4759 return false; 4760 } 4761 } 4762 // If we are a class we need to initialize all interfaces with default methods when we are 4763 // initialized. Check all of them. 4764 if (!klass->IsInterface()) { 4765 size_t num_interfaces = klass->GetIfTableCount(); 4766 for (size_t i = 0; i < num_interfaces; i++) { 4767 ObjPtr<mirror::Class> iface = klass->GetIfTable()->GetInterface(i); 4768 if (iface->HasDefaultMethods() && 4769 !CanWeInitializeClass(iface, can_init_statics, can_init_parents)) { 4770 return false; 4771 } 4772 } 4773 } 4774 } 4775 if (klass->IsInterface() || !klass->HasSuperClass()) { 4776 return true; 4777 } 4778 ObjPtr<mirror::Class> super_class = klass->GetSuperClass(); 4779 if (!can_init_parents && !super_class->IsInitialized()) { 4780 return false; 4781 } 4782 return CanWeInitializeClass(super_class, can_init_statics, can_init_parents); 4783 } 4784 4785 bool ClassLinker::InitializeClass(Thread* self, Handle<mirror::Class> klass, 4786 bool can_init_statics, bool can_init_parents) { 4787 // see JLS 3rd edition, 12.4.2 "Detailed Initialization Procedure" for the locking protocol 4788 4789 // Are we already initialized and therefore done? 4790 // Note: we differ from the JLS here as we don't do this under the lock, this is benign as 4791 // an initialized class will never change its state. 4792 if (klass->IsInitialized()) { 4793 return true; 4794 } 4795 4796 // Fast fail if initialization requires a full runtime. Not part of the JLS. 4797 if (!CanWeInitializeClass(klass.Get(), can_init_statics, can_init_parents)) { 4798 return false; 4799 } 4800 4801 self->AllowThreadSuspension(); 4802 uint64_t t0; 4803 { 4804 ObjectLock<mirror::Class> lock(self, klass); 4805 4806 // Re-check under the lock in case another thread initialized ahead of us. 4807 if (klass->IsInitialized()) { 4808 return true; 4809 } 4810 4811 // Was the class already found to be erroneous? Done under the lock to match the JLS. 4812 if (klass->IsErroneous()) { 4813 ThrowEarlierClassFailure(klass.Get(), true); 4814 VlogClassInitializationFailure(klass); 4815 return false; 4816 } 4817 4818 CHECK(klass->IsResolved() && !klass->IsErroneousResolved()) 4819 << klass->PrettyClass() << ": state=" << klass->GetStatus(); 4820 4821 if (!klass->IsVerified()) { 4822 VerifyClass(self, klass); 4823 if (!klass->IsVerified()) { 4824 // We failed to verify, expect either the klass to be erroneous or verification failed at 4825 // compile time. 4826 if (klass->IsErroneous()) { 4827 // The class is erroneous. This may be a verifier error, or another thread attempted 4828 // verification and/or initialization and failed. We can distinguish those cases by 4829 // whether an exception is already pending. 4830 if (self->IsExceptionPending()) { 4831 // Check that it's a VerifyError. 4832 DCHECK_EQ("java.lang.Class<java.lang.VerifyError>", 4833 mirror::Class::PrettyClass(self->GetException()->GetClass())); 4834 } else { 4835 // Check that another thread attempted initialization. 4836 DCHECK_NE(0, klass->GetClinitThreadId()); 4837 DCHECK_NE(self->GetTid(), klass->GetClinitThreadId()); 4838 // Need to rethrow the previous failure now. 4839 ThrowEarlierClassFailure(klass.Get(), true); 4840 } 4841 VlogClassInitializationFailure(klass); 4842 } else { 4843 CHECK(Runtime::Current()->IsAotCompiler()); 4844 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime); 4845 } 4846 return false; 4847 } else { 4848 self->AssertNoPendingException(); 4849 } 4850 4851 // A separate thread could have moved us all the way to initialized. A "simple" example 4852 // involves a subclass of the current class being initialized at the same time (which 4853 // will implicitly initialize the superclass, if scheduled that way). b/28254258 4854 DCHECK(!klass->IsErroneous()) << klass->GetStatus(); 4855 if (klass->IsInitialized()) { 4856 return true; 4857 } 4858 } 4859 4860 // If the class is kStatusInitializing, either this thread is 4861 // initializing higher up the stack or another thread has beat us 4862 // to initializing and we need to wait. Either way, this 4863 // invocation of InitializeClass will not be responsible for 4864 // running <clinit> and will return. 4865 if (klass->GetStatus() == mirror::Class::kStatusInitializing) { 4866 // Could have got an exception during verification. 4867 if (self->IsExceptionPending()) { 4868 VlogClassInitializationFailure(klass); 4869 return false; 4870 } 4871 // We caught somebody else in the act; was it us? 4872 if (klass->GetClinitThreadId() == self->GetTid()) { 4873 // Yes. That's fine. Return so we can continue initializing. 4874 return true; 4875 } 4876 // No. That's fine. Wait for another thread to finish initializing. 4877 return WaitForInitializeClass(klass, self, lock); 4878 } 4879 4880 bool has_oat_class = false; 4881 const OatFile::OatClass oat_class = 4882 (Runtime::Current()->IsStarted() && !Runtime::Current()->IsAotCompiler()) 4883 ? OatFile::FindOatClass(klass->GetDexFile(), klass->GetDexClassDefIndex(), &has_oat_class) 4884 : OatFile::OatClass::Invalid(); 4885 if (oat_class.GetStatus() < mirror::Class::kStatusSuperclassValidated && 4886 !ValidateSuperClassDescriptors(klass)) { 4887 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorResolved, self); 4888 return false; 4889 } 4890 self->AllowThreadSuspension(); 4891 4892 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusVerified) << klass->PrettyClass() 4893 << " self.tid=" << self->GetTid() << " clinit.tid=" << klass->GetClinitThreadId(); 4894 4895 // From here out other threads may observe that we're initializing and so changes of state 4896 // require the a notification. 4897 klass->SetClinitThreadId(self->GetTid()); 4898 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitializing, self); 4899 4900 t0 = NanoTime(); 4901 } 4902 4903 // Initialize super classes, must be done while initializing for the JLS. 4904 if (!klass->IsInterface() && klass->HasSuperClass()) { 4905 ObjPtr<mirror::Class> super_class = klass->GetSuperClass(); 4906 if (!super_class->IsInitialized()) { 4907 CHECK(!super_class->IsInterface()); 4908 CHECK(can_init_parents); 4909 StackHandleScope<1> hs(self); 4910 Handle<mirror::Class> handle_scope_super(hs.NewHandle(super_class)); 4911 bool super_initialized = InitializeClass(self, handle_scope_super, can_init_statics, true); 4912 if (!super_initialized) { 4913 // The super class was verified ahead of entering initializing, we should only be here if 4914 // the super class became erroneous due to initialization. 4915 CHECK(handle_scope_super->IsErroneous() && self->IsExceptionPending()) 4916 << "Super class initialization failed for " 4917 << handle_scope_super->PrettyDescriptor() 4918 << " that has unexpected status " << handle_scope_super->GetStatus() 4919 << "\nPending exception:\n" 4920 << (self->GetException() != nullptr ? self->GetException()->Dump() : ""); 4921 ObjectLock<mirror::Class> lock(self, klass); 4922 // Initialization failed because the super-class is erroneous. 4923 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorResolved, self); 4924 return false; 4925 } 4926 } 4927 } 4928 4929 if (!klass->IsInterface()) { 4930 // Initialize interfaces with default methods for the JLS. 4931 size_t num_direct_interfaces = klass->NumDirectInterfaces(); 4932 // Only setup the (expensive) handle scope if we actually need to. 4933 if (UNLIKELY(num_direct_interfaces > 0)) { 4934 StackHandleScope<1> hs_iface(self); 4935 MutableHandle<mirror::Class> handle_scope_iface(hs_iface.NewHandle<mirror::Class>(nullptr)); 4936 for (size_t i = 0; i < num_direct_interfaces; i++) { 4937 handle_scope_iface.Assign(mirror::Class::GetDirectInterface(self, klass.Get(), i)); 4938 CHECK(handle_scope_iface != nullptr) << klass->PrettyDescriptor() << " iface #" << i; 4939 CHECK(handle_scope_iface->IsInterface()); 4940 if (handle_scope_iface->HasBeenRecursivelyInitialized()) { 4941 // We have already done this for this interface. Skip it. 4942 continue; 4943 } 4944 // We cannot just call initialize class directly because we need to ensure that ALL 4945 // interfaces with default methods are initialized. Non-default interface initialization 4946 // will not affect other non-default super-interfaces. 4947 bool iface_initialized = InitializeDefaultInterfaceRecursive(self, 4948 handle_scope_iface, 4949 can_init_statics, 4950 can_init_parents); 4951 if (!iface_initialized) { 4952 ObjectLock<mirror::Class> lock(self, klass); 4953 // Initialization failed because one of our interfaces with default methods is erroneous. 4954 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorResolved, self); 4955 return false; 4956 } 4957 } 4958 } 4959 } 4960 4961 const size_t num_static_fields = klass->NumStaticFields(); 4962 if (num_static_fields > 0) { 4963 const DexFile::ClassDef* dex_class_def = klass->GetClassDef(); 4964 CHECK(dex_class_def != nullptr); 4965 const DexFile& dex_file = klass->GetDexFile(); 4966 StackHandleScope<3> hs(self); 4967 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(klass->GetClassLoader())); 4968 Handle<mirror::DexCache> dex_cache(hs.NewHandle(klass->GetDexCache())); 4969 4970 // Eagerly fill in static fields so that the we don't have to do as many expensive 4971 // Class::FindStaticField in ResolveField. 4972 for (size_t i = 0; i < num_static_fields; ++i) { 4973 ArtField* field = klass->GetStaticField(i); 4974 const uint32_t field_idx = field->GetDexFieldIndex(); 4975 ArtField* resolved_field = dex_cache->GetResolvedField(field_idx, image_pointer_size_); 4976 if (resolved_field == nullptr) { 4977 dex_cache->SetResolvedField(field_idx, field, image_pointer_size_); 4978 } else { 4979 DCHECK_EQ(field, resolved_field); 4980 } 4981 } 4982 4983 annotations::RuntimeEncodedStaticFieldValueIterator value_it(dex_file, 4984 &dex_cache, 4985 &class_loader, 4986 this, 4987 *dex_class_def); 4988 const uint8_t* class_data = dex_file.GetClassData(*dex_class_def); 4989 ClassDataItemIterator field_it(dex_file, class_data); 4990 if (value_it.HasNext()) { 4991 DCHECK(field_it.HasNextStaticField()); 4992 CHECK(can_init_statics); 4993 for ( ; value_it.HasNext(); value_it.Next(), field_it.Next()) { 4994 ArtField* field = ResolveField( 4995 dex_file, field_it.GetMemberIndex(), dex_cache, class_loader, true); 4996 if (Runtime::Current()->IsActiveTransaction()) { 4997 value_it.ReadValueToField<true>(field); 4998 } else { 4999 value_it.ReadValueToField<false>(field); 5000 } 5001 if (self->IsExceptionPending()) { 5002 break; 5003 } 5004 DCHECK(!value_it.HasNext() || field_it.HasNextStaticField()); 5005 } 5006 } 5007 } 5008 5009 5010 if (!self->IsExceptionPending()) { 5011 ArtMethod* clinit = klass->FindClassInitializer(image_pointer_size_); 5012 if (clinit != nullptr) { 5013 CHECK(can_init_statics); 5014 JValue result; 5015 clinit->Invoke(self, nullptr, 0, &result, "V"); 5016 } 5017 } 5018 self->AllowThreadSuspension(); 5019 uint64_t t1 = NanoTime(); 5020 5021 bool success = true; 5022 { 5023 ObjectLock<mirror::Class> lock(self, klass); 5024 5025 if (self->IsExceptionPending()) { 5026 WrapExceptionInInitializer(klass); 5027 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorResolved, self); 5028 success = false; 5029 } else if (Runtime::Current()->IsTransactionAborted()) { 5030 // The exception thrown when the transaction aborted has been caught and cleared 5031 // so we need to throw it again now. 5032 VLOG(compiler) << "Return from class initializer of " 5033 << mirror::Class::PrettyDescriptor(klass.Get()) 5034 << " without exception while transaction was aborted: re-throw it now."; 5035 Runtime::Current()->ThrowTransactionAbortError(self); 5036 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorResolved, self); 5037 success = false; 5038 } else { 5039 RuntimeStats* global_stats = Runtime::Current()->GetStats(); 5040 RuntimeStats* thread_stats = self->GetStats(); 5041 ++global_stats->class_init_count; 5042 ++thread_stats->class_init_count; 5043 global_stats->class_init_time_ns += (t1 - t0); 5044 thread_stats->class_init_time_ns += (t1 - t0); 5045 // Set the class as initialized except if failed to initialize static fields. 5046 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitialized, self); 5047 if (VLOG_IS_ON(class_linker)) { 5048 std::string temp; 5049 LOG(INFO) << "Initialized class " << klass->GetDescriptor(&temp) << " from " << 5050 klass->GetLocation(); 5051 } 5052 // Opportunistically set static method trampolines to their destination. 5053 FixupStaticTrampolines(klass.Get()); 5054 } 5055 } 5056 return success; 5057 } 5058 5059 // We recursively run down the tree of interfaces. We need to do this in the order they are declared 5060 // and perform the initialization only on those interfaces that contain default methods. 5061 bool ClassLinker::InitializeDefaultInterfaceRecursive(Thread* self, 5062 Handle<mirror::Class> iface, 5063 bool can_init_statics, 5064 bool can_init_parents) { 5065 CHECK(iface->IsInterface()); 5066 size_t num_direct_ifaces = iface->NumDirectInterfaces(); 5067 // Only create the (expensive) handle scope if we need it. 5068 if (UNLIKELY(num_direct_ifaces > 0)) { 5069 StackHandleScope<1> hs(self); 5070 MutableHandle<mirror::Class> handle_super_iface(hs.NewHandle<mirror::Class>(nullptr)); 5071 // First we initialize all of iface's super-interfaces recursively. 5072 for (size_t i = 0; i < num_direct_ifaces; i++) { 5073 ObjPtr<mirror::Class> super_iface = mirror::Class::GetDirectInterface(self, iface.Get(), i); 5074 CHECK(super_iface != nullptr) << iface->PrettyDescriptor() << " iface #" << i; 5075 if (!super_iface->HasBeenRecursivelyInitialized()) { 5076 // Recursive step 5077 handle_super_iface.Assign(super_iface); 5078 if (!InitializeDefaultInterfaceRecursive(self, 5079 handle_super_iface, 5080 can_init_statics, 5081 can_init_parents)) { 5082 return false; 5083 } 5084 } 5085 } 5086 } 5087 5088 bool result = true; 5089 // Then we initialize 'iface' if it has default methods. We do not need to (and in fact must not) 5090 // initialize if we don't have default methods. 5091 if (iface->HasDefaultMethods()) { 5092 result = EnsureInitialized(self, iface, can_init_statics, can_init_parents); 5093 } 5094 5095 // Mark that this interface has undergone recursive default interface initialization so we know we 5096 // can skip it on any later class initializations. We do this even if we are not a default 5097 // interface since we can still avoid the traversal. This is purely a performance optimization. 5098 if (result) { 5099 // TODO This should be done in a better way 5100 ObjectLock<mirror::Class> lock(self, iface); 5101 iface->SetRecursivelyInitialized(); 5102 } 5103 return result; 5104 } 5105 5106 bool ClassLinker::WaitForInitializeClass(Handle<mirror::Class> klass, 5107 Thread* self, 5108 ObjectLock<mirror::Class>& lock) 5109 REQUIRES_SHARED(Locks::mutator_lock_) { 5110 while (true) { 5111 self->AssertNoPendingException(); 5112 CHECK(!klass->IsInitialized()); 5113 lock.WaitIgnoringInterrupts(); 5114 5115 // When we wake up, repeat the test for init-in-progress. If 5116 // there's an exception pending (only possible if 5117 // we were not using WaitIgnoringInterrupts), bail out. 5118 if (self->IsExceptionPending()) { 5119 WrapExceptionInInitializer(klass); 5120 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorResolved, self); 5121 return false; 5122 } 5123 // Spurious wakeup? Go back to waiting. 5124 if (klass->GetStatus() == mirror::Class::kStatusInitializing) { 5125 continue; 5126 } 5127 if (klass->GetStatus() == mirror::Class::kStatusVerified && 5128 Runtime::Current()->IsAotCompiler()) { 5129 // Compile time initialization failed. 5130 return false; 5131 } 5132 if (klass->IsErroneous()) { 5133 // The caller wants an exception, but it was thrown in a 5134 // different thread. Synthesize one here. 5135 ThrowNoClassDefFoundError("<clinit> failed for class %s; see exception in other thread", 5136 klass->PrettyDescriptor().c_str()); 5137 VlogClassInitializationFailure(klass); 5138 return false; 5139 } 5140 if (klass->IsInitialized()) { 5141 return true; 5142 } 5143 LOG(FATAL) << "Unexpected class status. " << klass->PrettyClass() << " is " 5144 << klass->GetStatus(); 5145 } 5146 UNREACHABLE(); 5147 } 5148 5149 static void ThrowSignatureCheckResolveReturnTypeException(Handle<mirror::Class> klass, 5150 Handle<mirror::Class> super_klass, 5151 ArtMethod* method, 5152 ArtMethod* m) 5153 REQUIRES_SHARED(Locks::mutator_lock_) { 5154 DCHECK(Thread::Current()->IsExceptionPending()); 5155 DCHECK(!m->IsProxyMethod()); 5156 const DexFile* dex_file = m->GetDexFile(); 5157 const DexFile::MethodId& method_id = dex_file->GetMethodId(m->GetDexMethodIndex()); 5158 const DexFile::ProtoId& proto_id = dex_file->GetMethodPrototype(method_id); 5159 dex::TypeIndex return_type_idx = proto_id.return_type_idx_; 5160 std::string return_type = dex_file->PrettyType(return_type_idx); 5161 std::string class_loader = mirror::Object::PrettyTypeOf(m->GetDeclaringClass()->GetClassLoader()); 5162 ThrowWrappedLinkageError(klass.Get(), 5163 "While checking class %s method %s signature against %s %s: " 5164 "Failed to resolve return type %s with %s", 5165 mirror::Class::PrettyDescriptor(klass.Get()).c_str(), 5166 ArtMethod::PrettyMethod(method).c_str(), 5167 super_klass->IsInterface() ? "interface" : "superclass", 5168 mirror::Class::PrettyDescriptor(super_klass.Get()).c_str(), 5169 return_type.c_str(), class_loader.c_str()); 5170 } 5171 5172 static void ThrowSignatureCheckResolveArgException(Handle<mirror::Class> klass, 5173 Handle<mirror::Class> super_klass, 5174 ArtMethod* method, 5175 ArtMethod* m, 5176 uint32_t index, 5177 dex::TypeIndex arg_type_idx) 5178 REQUIRES_SHARED(Locks::mutator_lock_) { 5179 DCHECK(Thread::Current()->IsExceptionPending()); 5180 DCHECK(!m->IsProxyMethod()); 5181 const DexFile* dex_file = m->GetDexFile(); 5182 std::string arg_type = dex_file->PrettyType(arg_type_idx); 5183 std::string class_loader = mirror::Object::PrettyTypeOf(m->GetDeclaringClass()->GetClassLoader()); 5184 ThrowWrappedLinkageError(klass.Get(), 5185 "While checking class %s method %s signature against %s %s: " 5186 "Failed to resolve arg %u type %s with %s", 5187 mirror::Class::PrettyDescriptor(klass.Get()).c_str(), 5188 ArtMethod::PrettyMethod(method).c_str(), 5189 super_klass->IsInterface() ? "interface" : "superclass", 5190 mirror::Class::PrettyDescriptor(super_klass.Get()).c_str(), 5191 index, arg_type.c_str(), class_loader.c_str()); 5192 } 5193 5194 static void ThrowSignatureMismatch(Handle<mirror::Class> klass, 5195 Handle<mirror::Class> super_klass, 5196 ArtMethod* method, 5197 const std::string& error_msg) 5198 REQUIRES_SHARED(Locks::mutator_lock_) { 5199 ThrowLinkageError(klass.Get(), 5200 "Class %s method %s resolves differently in %s %s: %s", 5201 mirror::Class::PrettyDescriptor(klass.Get()).c_str(), 5202 ArtMethod::PrettyMethod(method).c_str(), 5203 super_klass->IsInterface() ? "interface" : "superclass", 5204 mirror::Class::PrettyDescriptor(super_klass.Get()).c_str(), 5205 error_msg.c_str()); 5206 } 5207 5208 static bool HasSameSignatureWithDifferentClassLoaders(Thread* self, 5209 Handle<mirror::Class> klass, 5210 Handle<mirror::Class> super_klass, 5211 ArtMethod* method1, 5212 ArtMethod* method2) 5213 REQUIRES_SHARED(Locks::mutator_lock_) { 5214 { 5215 StackHandleScope<1> hs(self); 5216 Handle<mirror::Class> return_type(hs.NewHandle(method1->GetReturnType(true /* resolve */))); 5217 if (UNLIKELY(return_type == nullptr)) { 5218 ThrowSignatureCheckResolveReturnTypeException(klass, super_klass, method1, method1); 5219 return false; 5220 } 5221 ObjPtr<mirror::Class> other_return_type = method2->GetReturnType(true /* resolve */); 5222 if (UNLIKELY(other_return_type == nullptr)) { 5223 ThrowSignatureCheckResolveReturnTypeException(klass, super_klass, method1, method2); 5224 return false; 5225 } 5226 if (UNLIKELY(other_return_type != return_type.Get())) { 5227 ThrowSignatureMismatch(klass, super_klass, method1, 5228 StringPrintf("Return types mismatch: %s(%p) vs %s(%p)", 5229 return_type->PrettyClassAndClassLoader().c_str(), 5230 return_type.Get(), 5231 other_return_type->PrettyClassAndClassLoader().c_str(), 5232 other_return_type.Ptr())); 5233 return false; 5234 } 5235 } 5236 const DexFile::TypeList* types1 = method1->GetParameterTypeList(); 5237 const DexFile::TypeList* types2 = method2->GetParameterTypeList(); 5238 if (types1 == nullptr) { 5239 if (types2 != nullptr && types2->Size() != 0) { 5240 ThrowSignatureMismatch(klass, super_klass, method1, 5241 StringPrintf("Type list mismatch with %s", 5242 method2->PrettyMethod(true).c_str())); 5243 return false; 5244 } 5245 return true; 5246 } else if (UNLIKELY(types2 == nullptr)) { 5247 if (types1->Size() != 0) { 5248 ThrowSignatureMismatch(klass, super_klass, method1, 5249 StringPrintf("Type list mismatch with %s", 5250 method2->PrettyMethod(true).c_str())); 5251 return false; 5252 } 5253 return true; 5254 } 5255 uint32_t num_types = types1->Size(); 5256 if (UNLIKELY(num_types != types2->Size())) { 5257 ThrowSignatureMismatch(klass, super_klass, method1, 5258 StringPrintf("Type list mismatch with %s", 5259 method2->PrettyMethod(true).c_str())); 5260 return false; 5261 } 5262 for (uint32_t i = 0; i < num_types; ++i) { 5263 StackHandleScope<1> hs(self); 5264 dex::TypeIndex param_type_idx = types1->GetTypeItem(i).type_idx_; 5265 Handle<mirror::Class> param_type(hs.NewHandle( 5266 method1->GetClassFromTypeIndex(param_type_idx, true /* resolve */))); 5267 if (UNLIKELY(param_type == nullptr)) { 5268 ThrowSignatureCheckResolveArgException(klass, super_klass, method1, 5269 method1, i, param_type_idx); 5270 return false; 5271 } 5272 dex::TypeIndex other_param_type_idx = types2->GetTypeItem(i).type_idx_; 5273 ObjPtr<mirror::Class> other_param_type = 5274 method2->GetClassFromTypeIndex(other_param_type_idx, true /* resolve */); 5275 if (UNLIKELY(other_param_type == nullptr)) { 5276 ThrowSignatureCheckResolveArgException(klass, super_klass, method1, 5277 method2, i, other_param_type_idx); 5278 return false; 5279 } 5280 if (UNLIKELY(param_type.Get() != other_param_type)) { 5281 ThrowSignatureMismatch(klass, super_klass, method1, 5282 StringPrintf("Parameter %u type mismatch: %s(%p) vs %s(%p)", 5283 i, 5284 param_type->PrettyClassAndClassLoader().c_str(), 5285 param_type.Get(), 5286 other_param_type->PrettyClassAndClassLoader().c_str(), 5287 other_param_type.Ptr())); 5288 return false; 5289 } 5290 } 5291 return true; 5292 } 5293 5294 5295 bool ClassLinker::ValidateSuperClassDescriptors(Handle<mirror::Class> klass) { 5296 if (klass->IsInterface()) { 5297 return true; 5298 } 5299 // Begin with the methods local to the superclass. 5300 Thread* self = Thread::Current(); 5301 StackHandleScope<1> hs(self); 5302 MutableHandle<mirror::Class> super_klass(hs.NewHandle<mirror::Class>(nullptr)); 5303 if (klass->HasSuperClass() && 5304 klass->GetClassLoader() != klass->GetSuperClass()->GetClassLoader()) { 5305 super_klass.Assign(klass->GetSuperClass()); 5306 for (int i = klass->GetSuperClass()->GetVTableLength() - 1; i >= 0; --i) { 5307 auto* m = klass->GetVTableEntry(i, image_pointer_size_); 5308 auto* super_m = klass->GetSuperClass()->GetVTableEntry(i, image_pointer_size_); 5309 if (m != super_m) { 5310 if (UNLIKELY(!HasSameSignatureWithDifferentClassLoaders(self, 5311 klass, 5312 super_klass, 5313 m, 5314 super_m))) { 5315 self->AssertPendingException(); 5316 return false; 5317 } 5318 } 5319 } 5320 } 5321 for (int32_t i = 0; i < klass->GetIfTableCount(); ++i) { 5322 super_klass.Assign(klass->GetIfTable()->GetInterface(i)); 5323 if (klass->GetClassLoader() != super_klass->GetClassLoader()) { 5324 uint32_t num_methods = super_klass->NumVirtualMethods(); 5325 for (uint32_t j = 0; j < num_methods; ++j) { 5326 auto* m = klass->GetIfTable()->GetMethodArray(i)->GetElementPtrSize<ArtMethod*>( 5327 j, image_pointer_size_); 5328 auto* super_m = super_klass->GetVirtualMethod(j, image_pointer_size_); 5329 if (m != super_m) { 5330 if (UNLIKELY(!HasSameSignatureWithDifferentClassLoaders(self, 5331 klass, 5332 super_klass, 5333 m, 5334 super_m))) { 5335 self->AssertPendingException(); 5336 return false; 5337 } 5338 } 5339 } 5340 } 5341 } 5342 return true; 5343 } 5344 5345 bool ClassLinker::EnsureInitialized(Thread* self, 5346 Handle<mirror::Class> c, 5347 bool can_init_fields, 5348 bool can_init_parents) { 5349 DCHECK(c != nullptr); 5350 if (c->IsInitialized()) { 5351 EnsureSkipAccessChecksMethods(c, image_pointer_size_); 5352 self->AssertNoPendingException(); 5353 return true; 5354 } 5355 const bool success = InitializeClass(self, c, can_init_fields, can_init_parents); 5356 if (!success) { 5357 if (can_init_fields && can_init_parents) { 5358 CHECK(self->IsExceptionPending()) << c->PrettyClass(); 5359 } 5360 } else { 5361 self->AssertNoPendingException(); 5362 } 5363 return success; 5364 } 5365 5366 void ClassLinker::FixupTemporaryDeclaringClass(ObjPtr<mirror::Class> temp_class, 5367 ObjPtr<mirror::Class> new_class) { 5368 DCHECK_EQ(temp_class->NumInstanceFields(), 0u); 5369 for (ArtField& field : new_class->GetIFields()) { 5370 if (field.GetDeclaringClass() == temp_class) { 5371 field.SetDeclaringClass(new_class); 5372 } 5373 } 5374 5375 DCHECK_EQ(temp_class->NumStaticFields(), 0u); 5376 for (ArtField& field : new_class->GetSFields()) { 5377 if (field.GetDeclaringClass() == temp_class) { 5378 field.SetDeclaringClass(new_class); 5379 } 5380 } 5381 5382 DCHECK_EQ(temp_class->NumDirectMethods(), 0u); 5383 DCHECK_EQ(temp_class->NumVirtualMethods(), 0u); 5384 for (auto& method : new_class->GetMethods(image_pointer_size_)) { 5385 if (method.GetDeclaringClass() == temp_class) { 5386 method.SetDeclaringClass(new_class); 5387 } 5388 } 5389 5390 // Make sure the remembered set and mod-union tables know that we updated some of the native 5391 // roots. 5392 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(new_class); 5393 } 5394 5395 void ClassLinker::RegisterClassLoader(ObjPtr<mirror::ClassLoader> class_loader) { 5396 CHECK(class_loader->GetAllocator() == nullptr); 5397 CHECK(class_loader->GetClassTable() == nullptr); 5398 Thread* const self = Thread::Current(); 5399 ClassLoaderData data; 5400 data.weak_root = self->GetJniEnv()->vm->AddWeakGlobalRef(self, class_loader); 5401 // Create and set the class table. 5402 data.class_table = new ClassTable; 5403 class_loader->SetClassTable(data.class_table); 5404 // Create and set the linear allocator. 5405 data.allocator = Runtime::Current()->CreateLinearAlloc(); 5406 class_loader->SetAllocator(data.allocator); 5407 // Add to the list so that we know to free the data later. 5408 class_loaders_.push_back(data); 5409 } 5410 5411 ClassTable* ClassLinker::InsertClassTableForClassLoader(ObjPtr<mirror::ClassLoader> class_loader) { 5412 if (class_loader == nullptr) { 5413 return boot_class_table_.get(); 5414 } 5415 ClassTable* class_table = class_loader->GetClassTable(); 5416 if (class_table == nullptr) { 5417 RegisterClassLoader(class_loader); 5418 class_table = class_loader->GetClassTable(); 5419 DCHECK(class_table != nullptr); 5420 } 5421 return class_table; 5422 } 5423 5424 ClassTable* ClassLinker::ClassTableForClassLoader(ObjPtr<mirror::ClassLoader> class_loader) { 5425 return class_loader == nullptr ? boot_class_table_.get() : class_loader->GetClassTable(); 5426 } 5427 5428 static ImTable* FindSuperImt(ObjPtr<mirror::Class> klass, PointerSize pointer_size) 5429 REQUIRES_SHARED(Locks::mutator_lock_) { 5430 while (klass->HasSuperClass()) { 5431 klass = klass->GetSuperClass(); 5432 if (klass->ShouldHaveImt()) { 5433 return klass->GetImt(pointer_size); 5434 } 5435 } 5436 return nullptr; 5437 } 5438 5439 bool ClassLinker::LinkClass(Thread* self, 5440 const char* descriptor, 5441 Handle<mirror::Class> klass, 5442 Handle<mirror::ObjectArray<mirror::Class>> interfaces, 5443 MutableHandle<mirror::Class>* h_new_class_out) { 5444 CHECK_EQ(mirror::Class::kStatusLoaded, klass->GetStatus()); 5445 5446 if (!LinkSuperClass(klass)) { 5447 return false; 5448 } 5449 ArtMethod* imt_data[ImTable::kSize]; 5450 // If there are any new conflicts compared to super class. 5451 bool new_conflict = false; 5452 std::fill_n(imt_data, arraysize(imt_data), Runtime::Current()->GetImtUnimplementedMethod()); 5453 if (!LinkMethods(self, klass, interfaces, &new_conflict, imt_data)) { 5454 return false; 5455 } 5456 if (!LinkInstanceFields(self, klass)) { 5457 return false; 5458 } 5459 size_t class_size; 5460 if (!LinkStaticFields(self, klass, &class_size)) { 5461 return false; 5462 } 5463 CreateReferenceInstanceOffsets(klass); 5464 CHECK_EQ(mirror::Class::kStatusLoaded, klass->GetStatus()); 5465 5466 ImTable* imt = nullptr; 5467 if (klass->ShouldHaveImt()) { 5468 // If there are any new conflicts compared to the super class we can not make a copy. There 5469 // can be cases where both will have a conflict method at the same slot without having the same 5470 // set of conflicts. In this case, we can not share the IMT since the conflict table slow path 5471 // will possibly create a table that is incorrect for either of the classes. 5472 // Same IMT with new_conflict does not happen very often. 5473 if (!new_conflict) { 5474 ImTable* super_imt = FindSuperImt(klass.Get(), image_pointer_size_); 5475 if (super_imt != nullptr) { 5476 bool imt_equals = true; 5477 for (size_t i = 0; i < ImTable::kSize && imt_equals; ++i) { 5478 imt_equals = imt_equals && (super_imt->Get(i, image_pointer_size_) == imt_data[i]); 5479 } 5480 if (imt_equals) { 5481 imt = super_imt; 5482 } 5483 } 5484 } 5485 if (imt == nullptr) { 5486 LinearAlloc* allocator = GetAllocatorForClassLoader(klass->GetClassLoader()); 5487 imt = reinterpret_cast<ImTable*>( 5488 allocator->Alloc(self, ImTable::SizeInBytes(image_pointer_size_))); 5489 if (imt == nullptr) { 5490 return false; 5491 } 5492 imt->Populate(imt_data, image_pointer_size_); 5493 } 5494 } 5495 5496 if (!klass->IsTemp() || (!init_done_ && klass->GetClassSize() == class_size)) { 5497 // We don't need to retire this class as it has no embedded tables or it was created the 5498 // correct size during class linker initialization. 5499 CHECK_EQ(klass->GetClassSize(), class_size) << klass->PrettyDescriptor(); 5500 5501 if (klass->ShouldHaveEmbeddedVTable()) { 5502 klass->PopulateEmbeddedVTable(image_pointer_size_); 5503 } 5504 if (klass->ShouldHaveImt()) { 5505 klass->SetImt(imt, image_pointer_size_); 5506 } 5507 5508 // Update CHA info based on whether we override methods. 5509 // Have to do this before setting the class as resolved which allows 5510 // instantiation of klass. 5511 if (cha_ != nullptr) { 5512 cha_->UpdateAfterLoadingOf(klass); 5513 } 5514 5515 // This will notify waiters on klass that saw the not yet resolved 5516 // class in the class_table_ during EnsureResolved. 5517 mirror::Class::SetStatus(klass, mirror::Class::kStatusResolved, self); 5518 h_new_class_out->Assign(klass.Get()); 5519 } else { 5520 CHECK(!klass->IsResolved()); 5521 // Retire the temporary class and create the correctly sized resolved class. 5522 StackHandleScope<1> hs(self); 5523 auto h_new_class = hs.NewHandle(klass->CopyOf(self, class_size, imt, image_pointer_size_)); 5524 // Set arrays to null since we don't want to have multiple classes with the same ArtField or 5525 // ArtMethod array pointers. If this occurs, it causes bugs in remembered sets since the GC 5526 // may not see any references to the target space and clean the card for a class if another 5527 // class had the same array pointer. 5528 klass->SetMethodsPtrUnchecked(nullptr, 0, 0); 5529 klass->SetSFieldsPtrUnchecked(nullptr); 5530 klass->SetIFieldsPtrUnchecked(nullptr); 5531 if (UNLIKELY(h_new_class == nullptr)) { 5532 self->AssertPendingOOMException(); 5533 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorUnresolved, self); 5534 return false; 5535 } 5536 5537 CHECK_EQ(h_new_class->GetClassSize(), class_size); 5538 ObjectLock<mirror::Class> lock(self, h_new_class); 5539 FixupTemporaryDeclaringClass(klass.Get(), h_new_class.Get()); 5540 5541 { 5542 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_); 5543 ObjPtr<mirror::ClassLoader> const class_loader = h_new_class.Get()->GetClassLoader(); 5544 ClassTable* const table = InsertClassTableForClassLoader(class_loader); 5545 ObjPtr<mirror::Class> existing = table->UpdateClass(descriptor, h_new_class.Get(), 5546 ComputeModifiedUtf8Hash(descriptor)); 5547 if (class_loader != nullptr) { 5548 // We updated the class in the class table, perform the write barrier so that the GC knows 5549 // about the change. 5550 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(class_loader); 5551 } 5552 CHECK_EQ(existing, klass.Get()); 5553 if (log_new_roots_) { 5554 new_class_roots_.push_back(GcRoot<mirror::Class>(h_new_class.Get())); 5555 } 5556 } 5557 5558 // Update CHA info based on whether we override methods. 5559 // Have to do this before setting the class as resolved which allows 5560 // instantiation of klass. 5561 if (cha_ != nullptr) { 5562 cha_->UpdateAfterLoadingOf(h_new_class); 5563 } 5564 5565 // This will notify waiters on temp class that saw the not yet resolved class in the 5566 // class_table_ during EnsureResolved. 5567 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetired, self); 5568 5569 CHECK_EQ(h_new_class->GetStatus(), mirror::Class::kStatusResolving); 5570 // This will notify waiters on new_class that saw the not yet resolved 5571 // class in the class_table_ during EnsureResolved. 5572 mirror::Class::SetStatus(h_new_class, mirror::Class::kStatusResolved, self); 5573 // Return the new class. 5574 h_new_class_out->Assign(h_new_class.Get()); 5575 } 5576 return true; 5577 } 5578 5579 bool ClassLinker::LoadSuperAndInterfaces(Handle<mirror::Class> klass, const DexFile& dex_file) { 5580 CHECK_EQ(mirror::Class::kStatusIdx, klass->GetStatus()); 5581 const DexFile::ClassDef& class_def = dex_file.GetClassDef(klass->GetDexClassDefIndex()); 5582 dex::TypeIndex super_class_idx = class_def.superclass_idx_; 5583 if (super_class_idx.IsValid()) { 5584 // Check that a class does not inherit from itself directly. 5585 // 5586 // TODO: This is a cheap check to detect the straightforward case 5587 // of a class extending itself (b/28685551), but we should do a 5588 // proper cycle detection on loaded classes, to detect all cases 5589 // of class circularity errors (b/28830038). 5590 if (super_class_idx == class_def.class_idx_) { 5591 ThrowClassCircularityError(klass.Get(), 5592 "Class %s extends itself", 5593 klass->PrettyDescriptor().c_str()); 5594 return false; 5595 } 5596 5597 ObjPtr<mirror::Class> super_class = ResolveType(dex_file, super_class_idx, klass.Get()); 5598 if (super_class == nullptr) { 5599 DCHECK(Thread::Current()->IsExceptionPending()); 5600 return false; 5601 } 5602 // Verify 5603 if (!klass->CanAccess(super_class)) { 5604 ThrowIllegalAccessError(klass.Get(), "Class %s extended by class %s is inaccessible", 5605 super_class->PrettyDescriptor().c_str(), 5606 klass->PrettyDescriptor().c_str()); 5607 return false; 5608 } 5609 CHECK(super_class->IsResolved()); 5610 klass->SetSuperClass(super_class); 5611 } 5612 const DexFile::TypeList* interfaces = dex_file.GetInterfacesList(class_def); 5613 if (interfaces != nullptr) { 5614 for (size_t i = 0; i < interfaces->Size(); i++) { 5615 dex::TypeIndex idx = interfaces->GetTypeItem(i).type_idx_; 5616 ObjPtr<mirror::Class> interface = ResolveType(dex_file, idx, klass.Get()); 5617 if (interface == nullptr) { 5618 DCHECK(Thread::Current()->IsExceptionPending()); 5619 return false; 5620 } 5621 // Verify 5622 if (!klass->CanAccess(interface)) { 5623 // TODO: the RI seemed to ignore this in my testing. 5624 ThrowIllegalAccessError(klass.Get(), 5625 "Interface %s implemented by class %s is inaccessible", 5626 interface->PrettyDescriptor().c_str(), 5627 klass->PrettyDescriptor().c_str()); 5628 return false; 5629 } 5630 } 5631 } 5632 // Mark the class as loaded. 5633 mirror::Class::SetStatus(klass, mirror::Class::kStatusLoaded, nullptr); 5634 return true; 5635 } 5636 5637 bool ClassLinker::LinkSuperClass(Handle<mirror::Class> klass) { 5638 CHECK(!klass->IsPrimitive()); 5639 ObjPtr<mirror::Class> super = klass->GetSuperClass(); 5640 if (klass.Get() == GetClassRoot(kJavaLangObject)) { 5641 if (super != nullptr) { 5642 ThrowClassFormatError(klass.Get(), "java.lang.Object must not have a superclass"); 5643 return false; 5644 } 5645 return true; 5646 } 5647 if (super == nullptr) { 5648 ThrowLinkageError(klass.Get(), "No superclass defined for class %s", 5649 klass->PrettyDescriptor().c_str()); 5650 return false; 5651 } 5652 // Verify 5653 if (super->IsFinal() || super->IsInterface()) { 5654 ThrowIncompatibleClassChangeError(klass.Get(), 5655 "Superclass %s of %s is %s", 5656 super->PrettyDescriptor().c_str(), 5657 klass->PrettyDescriptor().c_str(), 5658 super->IsFinal() ? "declared final" : "an interface"); 5659 return false; 5660 } 5661 if (!klass->CanAccess(super)) { 5662 ThrowIllegalAccessError(klass.Get(), "Superclass %s is inaccessible to class %s", 5663 super->PrettyDescriptor().c_str(), 5664 klass->PrettyDescriptor().c_str()); 5665 return false; 5666 } 5667 5668 // Inherit kAccClassIsFinalizable from the superclass in case this 5669 // class doesn't override finalize. 5670 if (super->IsFinalizable()) { 5671 klass->SetFinalizable(); 5672 } 5673 5674 // Inherit class loader flag form super class. 5675 if (super->IsClassLoaderClass()) { 5676 klass->SetClassLoaderClass(); 5677 } 5678 5679 // Inherit reference flags (if any) from the superclass. 5680 uint32_t reference_flags = (super->GetClassFlags() & mirror::kClassFlagReference); 5681 if (reference_flags != 0) { 5682 CHECK_EQ(klass->GetClassFlags(), 0u); 5683 klass->SetClassFlags(klass->GetClassFlags() | reference_flags); 5684 } 5685 // Disallow custom direct subclasses of java.lang.ref.Reference. 5686 if (init_done_ && super == GetClassRoot(kJavaLangRefReference)) { 5687 ThrowLinkageError(klass.Get(), 5688 "Class %s attempts to subclass java.lang.ref.Reference, which is not allowed", 5689 klass->PrettyDescriptor().c_str()); 5690 return false; 5691 } 5692 5693 if (kIsDebugBuild) { 5694 // Ensure super classes are fully resolved prior to resolving fields.. 5695 while (super != nullptr) { 5696 CHECK(super->IsResolved()); 5697 super = super->GetSuperClass(); 5698 } 5699 } 5700 return true; 5701 } 5702 5703 // Populate the class vtable and itable. Compute return type indices. 5704 bool ClassLinker::LinkMethods(Thread* self, 5705 Handle<mirror::Class> klass, 5706 Handle<mirror::ObjectArray<mirror::Class>> interfaces, 5707 bool* out_new_conflict, 5708 ArtMethod** out_imt) { 5709 self->AllowThreadSuspension(); 5710 // A map from vtable indexes to the method they need to be updated to point to. Used because we 5711 // need to have default methods be in the virtuals array of each class but we don't set that up 5712 // until LinkInterfaceMethods. 5713 std::unordered_map<size_t, ClassLinker::MethodTranslation> default_translations; 5714 // Link virtual methods then interface methods. 5715 // We set up the interface lookup table first because we need it to determine if we need to update 5716 // any vtable entries with new default method implementations. 5717 return SetupInterfaceLookupTable(self, klass, interfaces) 5718 && LinkVirtualMethods(self, klass, /*out*/ &default_translations) 5719 && LinkInterfaceMethods(self, klass, default_translations, out_new_conflict, out_imt); 5720 } 5721 5722 // Comparator for name and signature of a method, used in finding overriding methods. Implementation 5723 // avoids the use of handles, if it didn't then rather than compare dex files we could compare dex 5724 // caches in the implementation below. 5725 class MethodNameAndSignatureComparator FINAL : public ValueObject { 5726 public: 5727 explicit MethodNameAndSignatureComparator(ArtMethod* method) 5728 REQUIRES_SHARED(Locks::mutator_lock_) : 5729 dex_file_(method->GetDexFile()), mid_(&dex_file_->GetMethodId(method->GetDexMethodIndex())), 5730 name_(nullptr), name_len_(0) { 5731 DCHECK(!method->IsProxyMethod()) << method->PrettyMethod(); 5732 } 5733 5734 const char* GetName() { 5735 if (name_ == nullptr) { 5736 name_ = dex_file_->StringDataAndUtf16LengthByIdx(mid_->name_idx_, &name_len_); 5737 } 5738 return name_; 5739 } 5740 5741 bool HasSameNameAndSignature(ArtMethod* other) 5742 REQUIRES_SHARED(Locks::mutator_lock_) { 5743 DCHECK(!other->IsProxyMethod()) << other->PrettyMethod(); 5744 const DexFile* other_dex_file = other->GetDexFile(); 5745 const DexFile::MethodId& other_mid = other_dex_file->GetMethodId(other->GetDexMethodIndex()); 5746 if (dex_file_ == other_dex_file) { 5747 return mid_->name_idx_ == other_mid.name_idx_ && mid_->proto_idx_ == other_mid.proto_idx_; 5748 } 5749 GetName(); // Only used to make sure its calculated. 5750 uint32_t other_name_len; 5751 const char* other_name = other_dex_file->StringDataAndUtf16LengthByIdx(other_mid.name_idx_, 5752 &other_name_len); 5753 if (name_len_ != other_name_len || strcmp(name_, other_name) != 0) { 5754 return false; 5755 } 5756 return dex_file_->GetMethodSignature(*mid_) == other_dex_file->GetMethodSignature(other_mid); 5757 } 5758 5759 private: 5760 // Dex file for the method to compare against. 5761 const DexFile* const dex_file_; 5762 // MethodId for the method to compare against. 5763 const DexFile::MethodId* const mid_; 5764 // Lazily computed name from the dex file's strings. 5765 const char* name_; 5766 // Lazily computed name length. 5767 uint32_t name_len_; 5768 }; 5769 5770 class LinkVirtualHashTable { 5771 public: 5772 LinkVirtualHashTable(Handle<mirror::Class> klass, 5773 size_t hash_size, 5774 uint32_t* hash_table, 5775 PointerSize image_pointer_size) 5776 : klass_(klass), 5777 hash_size_(hash_size), 5778 hash_table_(hash_table), 5779 image_pointer_size_(image_pointer_size) { 5780 std::fill(hash_table_, hash_table_ + hash_size_, invalid_index_); 5781 } 5782 5783 void Add(uint32_t virtual_method_index) REQUIRES_SHARED(Locks::mutator_lock_) { 5784 ArtMethod* local_method = klass_->GetVirtualMethodDuringLinking( 5785 virtual_method_index, image_pointer_size_); 5786 const char* name = local_method->GetInterfaceMethodIfProxy(image_pointer_size_)->GetName(); 5787 uint32_t hash = ComputeModifiedUtf8Hash(name); 5788 uint32_t index = hash % hash_size_; 5789 // Linear probe until we have an empty slot. 5790 while (hash_table_[index] != invalid_index_) { 5791 if (++index == hash_size_) { 5792 index = 0; 5793 } 5794 } 5795 hash_table_[index] = virtual_method_index; 5796 } 5797 5798 uint32_t FindAndRemove(MethodNameAndSignatureComparator* comparator) 5799 REQUIRES_SHARED(Locks::mutator_lock_) { 5800 const char* name = comparator->GetName(); 5801 uint32_t hash = ComputeModifiedUtf8Hash(name); 5802 size_t index = hash % hash_size_; 5803 while (true) { 5804 const uint32_t value = hash_table_[index]; 5805 // Since linear probe makes continuous blocks, hitting an invalid index means we are done 5806 // the block and can safely assume not found. 5807 if (value == invalid_index_) { 5808 break; 5809 } 5810 if (value != removed_index_) { // This signifies not already overriden. 5811 ArtMethod* virtual_method = 5812 klass_->GetVirtualMethodDuringLinking(value, image_pointer_size_); 5813 if (comparator->HasSameNameAndSignature( 5814 virtual_method->GetInterfaceMethodIfProxy(image_pointer_size_))) { 5815 hash_table_[index] = removed_index_; 5816 return value; 5817 } 5818 } 5819 if (++index == hash_size_) { 5820 index = 0; 5821 } 5822 } 5823 return GetNotFoundIndex(); 5824 } 5825 5826 static uint32_t GetNotFoundIndex() { 5827 return invalid_index_; 5828 } 5829 5830 private: 5831 static const uint32_t invalid_index_; 5832 static const uint32_t removed_index_; 5833 5834 Handle<mirror::Class> klass_; 5835 const size_t hash_size_; 5836 uint32_t* const hash_table_; 5837 const PointerSize image_pointer_size_; 5838 }; 5839 5840 const uint32_t LinkVirtualHashTable::invalid_index_ = std::numeric_limits<uint32_t>::max(); 5841 const uint32_t LinkVirtualHashTable::removed_index_ = std::numeric_limits<uint32_t>::max() - 1; 5842 5843 bool ClassLinker::LinkVirtualMethods( 5844 Thread* self, 5845 Handle<mirror::Class> klass, 5846 /*out*/std::unordered_map<size_t, ClassLinker::MethodTranslation>* default_translations) { 5847 const size_t num_virtual_methods = klass->NumVirtualMethods(); 5848 if (klass->IsInterface()) { 5849 // No vtable. 5850 if (!IsUint<16>(num_virtual_methods)) { 5851 ThrowClassFormatError(klass.Get(), "Too many methods on interface: %zu", num_virtual_methods); 5852 return false; 5853 } 5854 bool has_defaults = false; 5855 // Assign each method an IMT index and set the default flag. 5856 for (size_t i = 0; i < num_virtual_methods; ++i) { 5857 ArtMethod* m = klass->GetVirtualMethodDuringLinking(i, image_pointer_size_); 5858 m->SetMethodIndex(i); 5859 if (!m->IsAbstract()) { 5860 m->SetAccessFlags(m->GetAccessFlags() | kAccDefault); 5861 has_defaults = true; 5862 } 5863 } 5864 // Mark that we have default methods so that we won't need to scan the virtual_methods_ array 5865 // during initialization. This is a performance optimization. We could simply traverse the 5866 // virtual_methods_ array again during initialization. 5867 if (has_defaults) { 5868 klass->SetHasDefaultMethods(); 5869 } 5870 return true; 5871 } else if (klass->HasSuperClass()) { 5872 const size_t super_vtable_length = klass->GetSuperClass()->GetVTableLength(); 5873 const size_t max_count = num_virtual_methods + super_vtable_length; 5874 StackHandleScope<2> hs(self); 5875 Handle<mirror::Class> super_class(hs.NewHandle(klass->GetSuperClass())); 5876 MutableHandle<mirror::PointerArray> vtable; 5877 if (super_class->ShouldHaveEmbeddedVTable()) { 5878 vtable = hs.NewHandle(AllocPointerArray(self, max_count)); 5879 if (UNLIKELY(vtable == nullptr)) { 5880 self->AssertPendingOOMException(); 5881 return false; 5882 } 5883 for (size_t i = 0; i < super_vtable_length; i++) { 5884 vtable->SetElementPtrSize( 5885 i, super_class->GetEmbeddedVTableEntry(i, image_pointer_size_), image_pointer_size_); 5886 } 5887 // We might need to change vtable if we have new virtual methods or new interfaces (since that 5888 // might give us new default methods). If no new interfaces then we can skip the rest since 5889 // the class cannot override any of the super-class's methods. This is required for 5890 // correctness since without it we might not update overridden default method vtable entries 5891 // correctly. 5892 if (num_virtual_methods == 0 && super_class->GetIfTableCount() == klass->GetIfTableCount()) { 5893 klass->SetVTable(vtable.Get()); 5894 return true; 5895 } 5896 } else { 5897 DCHECK(super_class->IsAbstract() && !super_class->IsArrayClass()); 5898 auto* super_vtable = super_class->GetVTable(); 5899 CHECK(super_vtable != nullptr) << super_class->PrettyClass(); 5900 // We might need to change vtable if we have new virtual methods or new interfaces (since that 5901 // might give us new default methods). See comment above. 5902 if (num_virtual_methods == 0 && super_class->GetIfTableCount() == klass->GetIfTableCount()) { 5903 klass->SetVTable(super_vtable); 5904 return true; 5905 } 5906 vtable = hs.NewHandle(down_cast<mirror::PointerArray*>( 5907 super_vtable->CopyOf(self, max_count))); 5908 if (UNLIKELY(vtable == nullptr)) { 5909 self->AssertPendingOOMException(); 5910 return false; 5911 } 5912 } 5913 // How the algorithm works: 5914 // 1. Populate hash table by adding num_virtual_methods from klass. The values in the hash 5915 // table are: invalid_index for unused slots, index super_vtable_length + i for a virtual 5916 // method which has not been matched to a vtable method, and j if the virtual method at the 5917 // index overrode the super virtual method at index j. 5918 // 2. Loop through super virtual methods, if they overwrite, update hash table to j 5919 // (j < super_vtable_length) to avoid redundant checks. (TODO maybe use this info for reducing 5920 // the need for the initial vtable which we later shrink back down). 5921 // 3. Add non overridden methods to the end of the vtable. 5922 static constexpr size_t kMaxStackHash = 250; 5923 // + 1 so that even if we only have new default methods we will still be able to use this hash 5924 // table (i.e. it will never have 0 size). 5925 const size_t hash_table_size = num_virtual_methods * 3 + 1; 5926 uint32_t* hash_table_ptr; 5927 std::unique_ptr<uint32_t[]> hash_heap_storage; 5928 if (hash_table_size <= kMaxStackHash) { 5929 hash_table_ptr = reinterpret_cast<uint32_t*>( 5930 alloca(hash_table_size * sizeof(*hash_table_ptr))); 5931 } else { 5932 hash_heap_storage.reset(new uint32_t[hash_table_size]); 5933 hash_table_ptr = hash_heap_storage.get(); 5934 } 5935 LinkVirtualHashTable hash_table(klass, hash_table_size, hash_table_ptr, image_pointer_size_); 5936 // Add virtual methods to the hash table. 5937 for (size_t i = 0; i < num_virtual_methods; ++i) { 5938 DCHECK(klass->GetVirtualMethodDuringLinking( 5939 i, image_pointer_size_)->GetDeclaringClass() != nullptr); 5940 hash_table.Add(i); 5941 } 5942 // Loop through each super vtable method and see if they are overridden by a method we added to 5943 // the hash table. 5944 for (size_t j = 0; j < super_vtable_length; ++j) { 5945 // Search the hash table to see if we are overridden by any method. 5946 ArtMethod* super_method = vtable->GetElementPtrSize<ArtMethod*>(j, image_pointer_size_); 5947 if (!klass->CanAccessMember(super_method->GetDeclaringClass(), 5948 super_method->GetAccessFlags())) { 5949 // Continue on to the next method since this one is package private and canot be overridden. 5950 // Before Android 4.1, the package-private method super_method might have been incorrectly 5951 // overridden. 5952 continue; 5953 } 5954 MethodNameAndSignatureComparator super_method_name_comparator( 5955 super_method->GetInterfaceMethodIfProxy(image_pointer_size_)); 5956 // We remove the method so that subsequent lookups will be faster by making the hash-map 5957 // smaller as we go on. 5958 uint32_t hash_index = hash_table.FindAndRemove(&super_method_name_comparator); 5959 if (hash_index != hash_table.GetNotFoundIndex()) { 5960 ArtMethod* virtual_method = klass->GetVirtualMethodDuringLinking( 5961 hash_index, image_pointer_size_); 5962 if (super_method->IsFinal()) { 5963 ThrowLinkageError(klass.Get(), "Method %s overrides final method in class %s", 5964 virtual_method->PrettyMethod().c_str(), 5965 super_method->GetDeclaringClassDescriptor()); 5966 return false; 5967 } 5968 vtable->SetElementPtrSize(j, virtual_method, image_pointer_size_); 5969 virtual_method->SetMethodIndex(j); 5970 } else if (super_method->IsOverridableByDefaultMethod()) { 5971 // We didn't directly override this method but we might through default methods... 5972 // Check for default method update. 5973 ArtMethod* default_method = nullptr; 5974 switch (FindDefaultMethodImplementation(self, 5975 super_method, 5976 klass, 5977 /*out*/&default_method)) { 5978 case DefaultMethodSearchResult::kDefaultConflict: { 5979 // A conflict was found looking for default methods. Note this (assuming it wasn't 5980 // pre-existing) in the translations map. 5981 if (UNLIKELY(!super_method->IsDefaultConflicting())) { 5982 // Don't generate another conflict method to reduce memory use as an optimization. 5983 default_translations->insert( 5984 {j, ClassLinker::MethodTranslation::CreateConflictingMethod()}); 5985 } 5986 break; 5987 } 5988 case DefaultMethodSearchResult::kAbstractFound: { 5989 // No conflict but method is abstract. 5990 // We note that this vtable entry must be made abstract. 5991 if (UNLIKELY(!super_method->IsAbstract())) { 5992 default_translations->insert( 5993 {j, ClassLinker::MethodTranslation::CreateAbstractMethod()}); 5994 } 5995 break; 5996 } 5997 case DefaultMethodSearchResult::kDefaultFound: { 5998 if (UNLIKELY(super_method->IsDefaultConflicting() || 5999 default_method->GetDeclaringClass() != super_method->GetDeclaringClass())) { 6000 // Found a default method implementation that is new. 6001 // TODO Refactor this add default methods to virtuals here and not in 6002 // LinkInterfaceMethods maybe. 6003 // The problem is default methods might override previously present 6004 // default-method or miranda-method vtable entries from the superclass. 6005 // Unfortunately we need these to be entries in this class's virtuals. We do not 6006 // give these entries there until LinkInterfaceMethods so we pass this map around 6007 // to let it know which vtable entries need to be updated. 6008 // Make a note that vtable entry j must be updated, store what it needs to be updated 6009 // to. We will allocate a virtual method slot in LinkInterfaceMethods and fix it up 6010 // then. 6011 default_translations->insert( 6012 {j, ClassLinker::MethodTranslation::CreateTranslatedMethod(default_method)}); 6013 VLOG(class_linker) << "Method " << super_method->PrettyMethod() 6014 << " overridden by default " 6015 << default_method->PrettyMethod() 6016 << " in " << mirror::Class::PrettyClass(klass.Get()); 6017 } 6018 break; 6019 } 6020 } 6021 } 6022 } 6023 size_t actual_count = super_vtable_length; 6024 // Add the non-overridden methods at the end. 6025 for (size_t i = 0; i < num_virtual_methods; ++i) { 6026 ArtMethod* local_method = klass->GetVirtualMethodDuringLinking(i, image_pointer_size_); 6027 size_t method_idx = local_method->GetMethodIndexDuringLinking(); 6028 if (method_idx < super_vtable_length && 6029 local_method == vtable->GetElementPtrSize<ArtMethod*>(method_idx, image_pointer_size_)) { 6030 continue; 6031 } 6032 vtable->SetElementPtrSize(actual_count, local_method, image_pointer_size_); 6033 local_method->SetMethodIndex(actual_count); 6034 ++actual_count; 6035 } 6036 if (!IsUint<16>(actual_count)) { 6037 ThrowClassFormatError(klass.Get(), "Too many methods defined on class: %zd", actual_count); 6038 return false; 6039 } 6040 // Shrink vtable if possible 6041 CHECK_LE(actual_count, max_count); 6042 if (actual_count < max_count) { 6043 vtable.Assign(down_cast<mirror::PointerArray*>(vtable->CopyOf(self, actual_count))); 6044 if (UNLIKELY(vtable == nullptr)) { 6045 self->AssertPendingOOMException(); 6046 return false; 6047 } 6048 } 6049 klass->SetVTable(vtable.Get()); 6050 } else { 6051 CHECK_EQ(klass.Get(), GetClassRoot(kJavaLangObject)); 6052 if (!IsUint<16>(num_virtual_methods)) { 6053 ThrowClassFormatError(klass.Get(), "Too many methods: %d", 6054 static_cast<int>(num_virtual_methods)); 6055 return false; 6056 } 6057 auto* vtable = AllocPointerArray(self, num_virtual_methods); 6058 if (UNLIKELY(vtable == nullptr)) { 6059 self->AssertPendingOOMException(); 6060 return false; 6061 } 6062 for (size_t i = 0; i < num_virtual_methods; ++i) { 6063 ArtMethod* virtual_method = klass->GetVirtualMethodDuringLinking(i, image_pointer_size_); 6064 vtable->SetElementPtrSize(i, virtual_method, image_pointer_size_); 6065 virtual_method->SetMethodIndex(i & 0xFFFF); 6066 } 6067 klass->SetVTable(vtable); 6068 } 6069 return true; 6070 } 6071 6072 // Determine if the given iface has any subinterface in the given list that declares the method 6073 // specified by 'target'. 6074 // 6075 // Arguments 6076 // - self: The thread we are running on 6077 // - target: A comparator that will match any method that overrides the method we are checking for 6078 // - iftable: The iftable we are searching for an overriding method on. 6079 // - ifstart: The index of the interface we are checking to see if anything overrides 6080 // - iface: The interface we are checking to see if anything overrides. 6081 // - image_pointer_size: 6082 // The image pointer size. 6083 // 6084 // Returns 6085 // - True: There is some method that matches the target comparator defined in an interface that 6086 // is a subtype of iface. 6087 // - False: There is no method that matches the target comparator in any interface that is a subtype 6088 // of iface. 6089 static bool ContainsOverridingMethodOf(Thread* self, 6090 MethodNameAndSignatureComparator& target, 6091 Handle<mirror::IfTable> iftable, 6092 size_t ifstart, 6093 Handle<mirror::Class> iface, 6094 PointerSize image_pointer_size) 6095 REQUIRES_SHARED(Locks::mutator_lock_) { 6096 DCHECK(self != nullptr); 6097 DCHECK(iface != nullptr); 6098 DCHECK(iftable != nullptr); 6099 DCHECK_GE(ifstart, 0u); 6100 DCHECK_LT(ifstart, iftable->Count()); 6101 DCHECK_EQ(iface.Get(), iftable->GetInterface(ifstart)); 6102 DCHECK(iface->IsInterface()); 6103 6104 size_t iftable_count = iftable->Count(); 6105 StackHandleScope<1> hs(self); 6106 MutableHandle<mirror::Class> current_iface(hs.NewHandle<mirror::Class>(nullptr)); 6107 for (size_t k = ifstart + 1; k < iftable_count; k++) { 6108 // Skip ifstart since our current interface obviously cannot override itself. 6109 current_iface.Assign(iftable->GetInterface(k)); 6110 // Iterate through every method on this interface. The order does not matter. 6111 for (ArtMethod& current_method : current_iface->GetDeclaredVirtualMethods(image_pointer_size)) { 6112 if (UNLIKELY(target.HasSameNameAndSignature( 6113 current_method.GetInterfaceMethodIfProxy(image_pointer_size)))) { 6114 // Check if the i'th interface is a subtype of this one. 6115 if (iface->IsAssignableFrom(current_iface.Get())) { 6116 return true; 6117 } 6118 break; 6119 } 6120 } 6121 } 6122 return false; 6123 } 6124 6125 // Find the default method implementation for 'interface_method' in 'klass'. Stores it into 6126 // out_default_method and returns kDefaultFound on success. If no default method was found return 6127 // kAbstractFound and store nullptr into out_default_method. If an error occurs (such as a 6128 // default_method conflict) it will return kDefaultConflict. 6129 ClassLinker::DefaultMethodSearchResult ClassLinker::FindDefaultMethodImplementation( 6130 Thread* self, 6131 ArtMethod* target_method, 6132 Handle<mirror::Class> klass, 6133 /*out*/ArtMethod** out_default_method) const { 6134 DCHECK(self != nullptr); 6135 DCHECK(target_method != nullptr); 6136 DCHECK(out_default_method != nullptr); 6137 6138 *out_default_method = nullptr; 6139 6140 // We organize the interface table so that, for interface I any subinterfaces J follow it in the 6141 // table. This lets us walk the table backwards when searching for default methods. The first one 6142 // we encounter is the best candidate since it is the most specific. Once we have found it we keep 6143 // track of it and then continue checking all other interfaces, since we need to throw an error if 6144 // we encounter conflicting default method implementations (one is not a subtype of the other). 6145 // 6146 // The order of unrelated interfaces does not matter and is not defined. 6147 size_t iftable_count = klass->GetIfTableCount(); 6148 if (iftable_count == 0) { 6149 // No interfaces. We have already reset out to null so just return kAbstractFound. 6150 return DefaultMethodSearchResult::kAbstractFound; 6151 } 6152 6153 StackHandleScope<3> hs(self); 6154 MutableHandle<mirror::Class> chosen_iface(hs.NewHandle<mirror::Class>(nullptr)); 6155 MutableHandle<mirror::IfTable> iftable(hs.NewHandle(klass->GetIfTable())); 6156 MutableHandle<mirror::Class> iface(hs.NewHandle<mirror::Class>(nullptr)); 6157 MethodNameAndSignatureComparator target_name_comparator( 6158 target_method->GetInterfaceMethodIfProxy(image_pointer_size_)); 6159 // Iterates over the klass's iftable in reverse 6160 for (size_t k = iftable_count; k != 0; ) { 6161 --k; 6162 6163 DCHECK_LT(k, iftable->Count()); 6164 6165 iface.Assign(iftable->GetInterface(k)); 6166 // Iterate through every declared method on this interface. The order does not matter. 6167 for (auto& method_iter : iface->GetDeclaredVirtualMethods(image_pointer_size_)) { 6168 ArtMethod* current_method = &method_iter; 6169 // Skip abstract methods and methods with different names. 6170 if (current_method->IsAbstract() || 6171 !target_name_comparator.HasSameNameAndSignature( 6172 current_method->GetInterfaceMethodIfProxy(image_pointer_size_))) { 6173 continue; 6174 } else if (!current_method->IsPublic()) { 6175 // The verifier should have caught the non-public method for dex version 37. Just warn and 6176 // skip it since this is from before default-methods so we don't really need to care that it 6177 // has code. 6178 LOG(WARNING) << "Interface method " << current_method->PrettyMethod() 6179 << " is not public! " 6180 << "This will be a fatal error in subsequent versions of android. " 6181 << "Continuing anyway."; 6182 } 6183 if (UNLIKELY(chosen_iface != nullptr)) { 6184 // We have multiple default impls of the same method. This is a potential default conflict. 6185 // We need to check if this possibly conflicting method is either a superclass of the chosen 6186 // default implementation or is overridden by a non-default interface method. In either case 6187 // there is no conflict. 6188 if (!iface->IsAssignableFrom(chosen_iface.Get()) && 6189 !ContainsOverridingMethodOf(self, 6190 target_name_comparator, 6191 iftable, 6192 k, 6193 iface, 6194 image_pointer_size_)) { 6195 VLOG(class_linker) << "Conflicting default method implementations found: " 6196 << current_method->PrettyMethod() << " and " 6197 << ArtMethod::PrettyMethod(*out_default_method) << " in class " 6198 << klass->PrettyClass() << " conflict."; 6199 *out_default_method = nullptr; 6200 return DefaultMethodSearchResult::kDefaultConflict; 6201 } else { 6202 break; // Continue checking at the next interface. 6203 } 6204 } else { 6205 // chosen_iface == null 6206 if (!ContainsOverridingMethodOf(self, 6207 target_name_comparator, 6208 iftable, 6209 k, 6210 iface, 6211 image_pointer_size_)) { 6212 // Don't set this as the chosen interface if something else is overriding it (because that 6213 // other interface would be potentially chosen instead if it was default). If the other 6214 // interface was abstract then we wouldn't select this interface as chosen anyway since 6215 // the abstract method masks it. 6216 *out_default_method = current_method; 6217 chosen_iface.Assign(iface.Get()); 6218 // We should now finish traversing the graph to find if we have default methods that 6219 // conflict. 6220 } else { 6221 VLOG(class_linker) << "A default method '" << current_method->PrettyMethod() 6222 << "' was " 6223 << "skipped because it was overridden by an abstract method in a " 6224 << "subinterface on class '" << klass->PrettyClass() << "'"; 6225 } 6226 } 6227 break; 6228 } 6229 } 6230 if (*out_default_method != nullptr) { 6231 VLOG(class_linker) << "Default method '" << (*out_default_method)->PrettyMethod() 6232 << "' selected " 6233 << "as the implementation for '" << target_method->PrettyMethod() 6234 << "' in '" << klass->PrettyClass() << "'"; 6235 return DefaultMethodSearchResult::kDefaultFound; 6236 } else { 6237 return DefaultMethodSearchResult::kAbstractFound; 6238 } 6239 } 6240 6241 ArtMethod* ClassLinker::AddMethodToConflictTable(ObjPtr<mirror::Class> klass, 6242 ArtMethod* conflict_method, 6243 ArtMethod* interface_method, 6244 ArtMethod* method, 6245 bool force_new_conflict_method) { 6246 ImtConflictTable* current_table = conflict_method->GetImtConflictTable(kRuntimePointerSize); 6247 Runtime* const runtime = Runtime::Current(); 6248 LinearAlloc* linear_alloc = GetAllocatorForClassLoader(klass->GetClassLoader()); 6249 bool new_entry = conflict_method == runtime->GetImtConflictMethod() || force_new_conflict_method; 6250 6251 // Create a new entry if the existing one is the shared conflict method. 6252 ArtMethod* new_conflict_method = new_entry 6253 ? runtime->CreateImtConflictMethod(linear_alloc) 6254 : conflict_method; 6255 6256 // Allocate a new table. Note that we will leak this table at the next conflict, 6257 // but that's a tradeoff compared to making the table fixed size. 6258 void* data = linear_alloc->Alloc( 6259 Thread::Current(), ImtConflictTable::ComputeSizeWithOneMoreEntry(current_table, 6260 image_pointer_size_)); 6261 if (data == nullptr) { 6262 LOG(ERROR) << "Failed to allocate conflict table"; 6263 return conflict_method; 6264 } 6265 ImtConflictTable* new_table = new (data) ImtConflictTable(current_table, 6266 interface_method, 6267 method, 6268 image_pointer_size_); 6269 6270 // Do a fence to ensure threads see the data in the table before it is assigned 6271 // to the conflict method. 6272 // Note that there is a race in the presence of multiple threads and we may leak 6273 // memory from the LinearAlloc, but that's a tradeoff compared to using 6274 // atomic operations. 6275 QuasiAtomic::ThreadFenceRelease(); 6276 new_conflict_method->SetImtConflictTable(new_table, image_pointer_size_); 6277 return new_conflict_method; 6278 } 6279 6280 bool ClassLinker::AllocateIfTableMethodArrays(Thread* self, 6281 Handle<mirror::Class> klass, 6282 Handle<mirror::IfTable> iftable) { 6283 DCHECK(!klass->IsInterface()); 6284 const bool has_superclass = klass->HasSuperClass(); 6285 const bool extend_super_iftable = has_superclass; 6286 const size_t ifcount = klass->GetIfTableCount(); 6287 const size_t super_ifcount = has_superclass ? klass->GetSuperClass()->GetIfTableCount() : 0U; 6288 for (size_t i = 0; i < ifcount; ++i) { 6289 size_t num_methods = iftable->GetInterface(i)->NumDeclaredVirtualMethods(); 6290 if (num_methods > 0) { 6291 const bool is_super = i < super_ifcount; 6292 // This is an interface implemented by a super-class. Therefore we can just copy the method 6293 // array from the superclass. 6294 const bool super_interface = is_super && extend_super_iftable; 6295 ObjPtr<mirror::PointerArray> method_array; 6296 if (super_interface) { 6297 ObjPtr<mirror::IfTable> if_table = klass->GetSuperClass()->GetIfTable(); 6298 DCHECK(if_table != nullptr); 6299 DCHECK(if_table->GetMethodArray(i) != nullptr); 6300 // If we are working on a super interface, try extending the existing method array. 6301 method_array = down_cast<mirror::PointerArray*>(if_table->GetMethodArray(i)->Clone(self)); 6302 } else { 6303 method_array = AllocPointerArray(self, num_methods); 6304 } 6305 if (UNLIKELY(method_array == nullptr)) { 6306 self->AssertPendingOOMException(); 6307 return false; 6308 } 6309 iftable->SetMethodArray(i, method_array); 6310 } 6311 } 6312 return true; 6313 } 6314 6315 void ClassLinker::SetIMTRef(ArtMethod* unimplemented_method, 6316 ArtMethod* imt_conflict_method, 6317 ArtMethod* current_method, 6318 /*out*/bool* new_conflict, 6319 /*out*/ArtMethod** imt_ref) { 6320 // Place method in imt if entry is empty, place conflict otherwise. 6321 if (*imt_ref == unimplemented_method) { 6322 *imt_ref = current_method; 6323 } else if (!(*imt_ref)->IsRuntimeMethod()) { 6324 // If we are not a conflict and we have the same signature and name as the imt 6325 // entry, it must be that we overwrote a superclass vtable entry. 6326 // Note that we have checked IsRuntimeMethod, as there may be multiple different 6327 // conflict methods. 6328 MethodNameAndSignatureComparator imt_comparator( 6329 (*imt_ref)->GetInterfaceMethodIfProxy(image_pointer_size_)); 6330 if (imt_comparator.HasSameNameAndSignature( 6331 current_method->GetInterfaceMethodIfProxy(image_pointer_size_))) { 6332 *imt_ref = current_method; 6333 } else { 6334 *imt_ref = imt_conflict_method; 6335 *new_conflict = true; 6336 } 6337 } else { 6338 // Place the default conflict method. Note that there may be an existing conflict 6339 // method in the IMT, but it could be one tailored to the super class, with a 6340 // specific ImtConflictTable. 6341 *imt_ref = imt_conflict_method; 6342 *new_conflict = true; 6343 } 6344 } 6345 6346 void ClassLinker::FillIMTAndConflictTables(ObjPtr<mirror::Class> klass) { 6347 DCHECK(klass->ShouldHaveImt()) << klass->PrettyClass(); 6348 DCHECK(!klass->IsTemp()) << klass->PrettyClass(); 6349 ArtMethod* imt_data[ImTable::kSize]; 6350 Runtime* const runtime = Runtime::Current(); 6351 ArtMethod* const unimplemented_method = runtime->GetImtUnimplementedMethod(); 6352 ArtMethod* const conflict_method = runtime->GetImtConflictMethod(); 6353 std::fill_n(imt_data, arraysize(imt_data), unimplemented_method); 6354 if (klass->GetIfTable() != nullptr) { 6355 bool new_conflict = false; 6356 FillIMTFromIfTable(klass->GetIfTable(), 6357 unimplemented_method, 6358 conflict_method, 6359 klass, 6360 /*create_conflict_tables*/true, 6361 /*ignore_copied_methods*/false, 6362 &new_conflict, 6363 &imt_data[0]); 6364 } 6365 if (!klass->ShouldHaveImt()) { 6366 return; 6367 } 6368 // Compare the IMT with the super class including the conflict methods. If they are equivalent, 6369 // we can just use the same pointer. 6370 ImTable* imt = nullptr; 6371 ObjPtr<mirror::Class> super_class = klass->GetSuperClass(); 6372 if (super_class != nullptr && super_class->ShouldHaveImt()) { 6373 ImTable* super_imt = super_class->GetImt(image_pointer_size_); 6374 bool same = true; 6375 for (size_t i = 0; same && i < ImTable::kSize; ++i) { 6376 ArtMethod* method = imt_data[i]; 6377 ArtMethod* super_method = super_imt->Get(i, image_pointer_size_); 6378 if (method != super_method) { 6379 bool is_conflict_table = method->IsRuntimeMethod() && 6380 method != unimplemented_method && 6381 method != conflict_method; 6382 // Verify conflict contents. 6383 bool super_conflict_table = super_method->IsRuntimeMethod() && 6384 super_method != unimplemented_method && 6385 super_method != conflict_method; 6386 if (!is_conflict_table || !super_conflict_table) { 6387 same = false; 6388 } else { 6389 ImtConflictTable* table1 = method->GetImtConflictTable(image_pointer_size_); 6390 ImtConflictTable* table2 = super_method->GetImtConflictTable(image_pointer_size_); 6391 same = same && table1->Equals(table2, image_pointer_size_); 6392 } 6393 } 6394 } 6395 if (same) { 6396 imt = super_imt; 6397 } 6398 } 6399 if (imt == nullptr) { 6400 imt = klass->GetImt(image_pointer_size_); 6401 DCHECK(imt != nullptr); 6402 imt->Populate(imt_data, image_pointer_size_); 6403 } else { 6404 klass->SetImt(imt, image_pointer_size_); 6405 } 6406 } 6407 6408 ImtConflictTable* ClassLinker::CreateImtConflictTable(size_t count, 6409 LinearAlloc* linear_alloc, 6410 PointerSize image_pointer_size) { 6411 void* data = linear_alloc->Alloc(Thread::Current(), 6412 ImtConflictTable::ComputeSize(count, 6413 image_pointer_size)); 6414 return (data != nullptr) ? new (data) ImtConflictTable(count, image_pointer_size) : nullptr; 6415 } 6416 6417 ImtConflictTable* ClassLinker::CreateImtConflictTable(size_t count, LinearAlloc* linear_alloc) { 6418 return CreateImtConflictTable(count, linear_alloc, image_pointer_size_); 6419 } 6420 6421 void ClassLinker::FillIMTFromIfTable(ObjPtr<mirror::IfTable> if_table, 6422 ArtMethod* unimplemented_method, 6423 ArtMethod* imt_conflict_method, 6424 ObjPtr<mirror::Class> klass, 6425 bool create_conflict_tables, 6426 bool ignore_copied_methods, 6427 /*out*/bool* new_conflict, 6428 /*out*/ArtMethod** imt) { 6429 uint32_t conflict_counts[ImTable::kSize] = {}; 6430 for (size_t i = 0, length = if_table->Count(); i < length; ++i) { 6431 ObjPtr<mirror::Class> interface = if_table->GetInterface(i); 6432 const size_t num_virtuals = interface->NumVirtualMethods(); 6433 const size_t method_array_count = if_table->GetMethodArrayCount(i); 6434 // Virtual methods can be larger than the if table methods if there are default methods. 6435 DCHECK_GE(num_virtuals, method_array_count); 6436 if (kIsDebugBuild) { 6437 if (klass->IsInterface()) { 6438 DCHECK_EQ(method_array_count, 0u); 6439 } else { 6440 DCHECK_EQ(interface->NumDeclaredVirtualMethods(), method_array_count); 6441 } 6442 } 6443 if (method_array_count == 0) { 6444 continue; 6445 } 6446 auto* method_array = if_table->GetMethodArray(i); 6447 for (size_t j = 0; j < method_array_count; ++j) { 6448 ArtMethod* implementation_method = 6449 method_array->GetElementPtrSize<ArtMethod*>(j, image_pointer_size_); 6450 if (ignore_copied_methods && implementation_method->IsCopied()) { 6451 continue; 6452 } 6453 DCHECK(implementation_method != nullptr); 6454 // Miranda methods cannot be used to implement an interface method, but they are safe to put 6455 // in the IMT since their entrypoint is the interface trampoline. If we put any copied methods 6456 // or interface methods in the IMT here they will not create extra conflicts since we compare 6457 // names and signatures in SetIMTRef. 6458 ArtMethod* interface_method = interface->GetVirtualMethod(j, image_pointer_size_); 6459 const uint32_t imt_index = ImTable::GetImtIndex(interface_method); 6460 6461 // There is only any conflicts if all of the interface methods for an IMT slot don't have 6462 // the same implementation method, keep track of this to avoid creating a conflict table in 6463 // this case. 6464 6465 // Conflict table size for each IMT slot. 6466 ++conflict_counts[imt_index]; 6467 6468 SetIMTRef(unimplemented_method, 6469 imt_conflict_method, 6470 implementation_method, 6471 /*out*/new_conflict, 6472 /*out*/&imt[imt_index]); 6473 } 6474 } 6475 6476 if (create_conflict_tables) { 6477 // Create the conflict tables. 6478 LinearAlloc* linear_alloc = GetAllocatorForClassLoader(klass->GetClassLoader()); 6479 for (size_t i = 0; i < ImTable::kSize; ++i) { 6480 size_t conflicts = conflict_counts[i]; 6481 if (imt[i] == imt_conflict_method) { 6482 ImtConflictTable* new_table = CreateImtConflictTable(conflicts, linear_alloc); 6483 if (new_table != nullptr) { 6484 ArtMethod* new_conflict_method = 6485 Runtime::Current()->CreateImtConflictMethod(linear_alloc); 6486 new_conflict_method->SetImtConflictTable(new_table, image_pointer_size_); 6487 imt[i] = new_conflict_method; 6488 } else { 6489 LOG(ERROR) << "Failed to allocate conflict table"; 6490 imt[i] = imt_conflict_method; 6491 } 6492 } else { 6493 DCHECK_NE(imt[i], imt_conflict_method); 6494 } 6495 } 6496 6497 for (size_t i = 0, length = if_table->Count(); i < length; ++i) { 6498 ObjPtr<mirror::Class> interface = if_table->GetInterface(i); 6499 const size_t method_array_count = if_table->GetMethodArrayCount(i); 6500 // Virtual methods can be larger than the if table methods if there are default methods. 6501 if (method_array_count == 0) { 6502 continue; 6503 } 6504 auto* method_array = if_table->GetMethodArray(i); 6505 for (size_t j = 0; j < method_array_count; ++j) { 6506 ArtMethod* implementation_method = 6507 method_array->GetElementPtrSize<ArtMethod*>(j, image_pointer_size_); 6508 if (ignore_copied_methods && implementation_method->IsCopied()) { 6509 continue; 6510 } 6511 DCHECK(implementation_method != nullptr); 6512 ArtMethod* interface_method = interface->GetVirtualMethod(j, image_pointer_size_); 6513 const uint32_t imt_index = ImTable::GetImtIndex(interface_method); 6514 if (!imt[imt_index]->IsRuntimeMethod() || 6515 imt[imt_index] == unimplemented_method || 6516 imt[imt_index] == imt_conflict_method) { 6517 continue; 6518 } 6519 ImtConflictTable* table = imt[imt_index]->GetImtConflictTable(image_pointer_size_); 6520 const size_t num_entries = table->NumEntries(image_pointer_size_); 6521 table->SetInterfaceMethod(num_entries, image_pointer_size_, interface_method); 6522 table->SetImplementationMethod(num_entries, image_pointer_size_, implementation_method); 6523 } 6524 } 6525 } 6526 } 6527 6528 // Simple helper function that checks that no subtypes of 'val' are contained within the 'classes' 6529 // set. 6530 static bool NotSubinterfaceOfAny( 6531 const std::unordered_set<ObjPtr<mirror::Class>, HashObjPtr>& classes, 6532 ObjPtr<mirror::Class> val) 6533 REQUIRES(Roles::uninterruptible_) 6534 REQUIRES_SHARED(Locks::mutator_lock_) { 6535 DCHECK(val != nullptr); 6536 for (ObjPtr<mirror::Class> c : classes) { 6537 if (val->IsAssignableFrom(c)) { 6538 return false; 6539 } 6540 } 6541 return true; 6542 } 6543 6544 // Fills in and flattens the interface inheritance hierarchy. 6545 // 6546 // By the end of this function all interfaces in the transitive closure of to_process are added to 6547 // the iftable and every interface precedes all of its sub-interfaces in this list. 6548 // 6549 // all I, J: Interface | I <: J implies J precedes I 6550 // 6551 // (note A <: B means that A is a subtype of B) 6552 // 6553 // This returns the total number of items in the iftable. The iftable might be resized down after 6554 // this call. 6555 // 6556 // We order this backwards so that we do not need to reorder superclass interfaces when new 6557 // interfaces are added in subclass's interface tables. 6558 // 6559 // Upon entry into this function iftable is a copy of the superclass's iftable with the first 6560 // super_ifcount entries filled in with the transitive closure of the interfaces of the superclass. 6561 // The other entries are uninitialized. We will fill in the remaining entries in this function. The 6562 // iftable must be large enough to hold all interfaces without changing its size. 6563 static size_t FillIfTable(ObjPtr<mirror::IfTable> iftable, 6564 size_t super_ifcount, 6565 std::vector<mirror::Class*> to_process) 6566 REQUIRES(Roles::uninterruptible_) 6567 REQUIRES_SHARED(Locks::mutator_lock_) { 6568 // This is the set of all class's already in the iftable. Used to make checking if a class has 6569 // already been added quicker. 6570 std::unordered_set<ObjPtr<mirror::Class>, HashObjPtr> classes_in_iftable; 6571 // The first super_ifcount elements are from the superclass. We note that they are already added. 6572 for (size_t i = 0; i < super_ifcount; i++) { 6573 ObjPtr<mirror::Class> iface = iftable->GetInterface(i); 6574 DCHECK(NotSubinterfaceOfAny(classes_in_iftable, iface)) << "Bad ordering."; 6575 classes_in_iftable.insert(iface); 6576 } 6577 size_t filled_ifcount = super_ifcount; 6578 for (ObjPtr<mirror::Class> interface : to_process) { 6579 // Let us call the first filled_ifcount elements of iftable the current-iface-list. 6580 // At this point in the loop current-iface-list has the invariant that: 6581 // for every pair of interfaces I,J within it: 6582 // if index_of(I) < index_of(J) then I is not a subtype of J 6583 6584 // If we have already seen this element then all of its super-interfaces must already be in the 6585 // current-iface-list so we can skip adding it. 6586 if (!ContainsElement(classes_in_iftable, interface)) { 6587 // We haven't seen this interface so add all of its super-interfaces onto the 6588 // current-iface-list, skipping those already on it. 6589 int32_t ifcount = interface->GetIfTableCount(); 6590 for (int32_t j = 0; j < ifcount; j++) { 6591 ObjPtr<mirror::Class> super_interface = interface->GetIfTable()->GetInterface(j); 6592 if (!ContainsElement(classes_in_iftable, super_interface)) { 6593 DCHECK(NotSubinterfaceOfAny(classes_in_iftable, super_interface)) << "Bad ordering."; 6594 classes_in_iftable.insert(super_interface); 6595 iftable->SetInterface(filled_ifcount, super_interface); 6596 filled_ifcount++; 6597 } 6598 } 6599 DCHECK(NotSubinterfaceOfAny(classes_in_iftable, interface)) << "Bad ordering"; 6600 // Place this interface onto the current-iface-list after all of its super-interfaces. 6601 classes_in_iftable.insert(interface); 6602 iftable->SetInterface(filled_ifcount, interface); 6603 filled_ifcount++; 6604 } else if (kIsDebugBuild) { 6605 // Check all super-interfaces are already in the list. 6606 int32_t ifcount = interface->GetIfTableCount(); 6607 for (int32_t j = 0; j < ifcount; j++) { 6608 ObjPtr<mirror::Class> super_interface = interface->GetIfTable()->GetInterface(j); 6609 DCHECK(ContainsElement(classes_in_iftable, super_interface)) 6610 << "Iftable does not contain " << mirror::Class::PrettyClass(super_interface) 6611 << ", a superinterface of " << interface->PrettyClass(); 6612 } 6613 } 6614 } 6615 if (kIsDebugBuild) { 6616 // Check that the iftable is ordered correctly. 6617 for (size_t i = 0; i < filled_ifcount; i++) { 6618 ObjPtr<mirror::Class> if_a = iftable->GetInterface(i); 6619 for (size_t j = i + 1; j < filled_ifcount; j++) { 6620 ObjPtr<mirror::Class> if_b = iftable->GetInterface(j); 6621 // !(if_a <: if_b) 6622 CHECK(!if_b->IsAssignableFrom(if_a)) 6623 << "Bad interface order: " << mirror::Class::PrettyClass(if_a) << " (index " << i 6624 << ") extends " 6625 << if_b->PrettyClass() << " (index " << j << ") and so should be after it in the " 6626 << "interface list."; 6627 } 6628 } 6629 } 6630 return filled_ifcount; 6631 } 6632 6633 bool ClassLinker::SetupInterfaceLookupTable(Thread* self, Handle<mirror::Class> klass, 6634 Handle<mirror::ObjectArray<mirror::Class>> interfaces) { 6635 StackHandleScope<1> hs(self); 6636 const bool has_superclass = klass->HasSuperClass(); 6637 const size_t super_ifcount = has_superclass ? klass->GetSuperClass()->GetIfTableCount() : 0U; 6638 const bool have_interfaces = interfaces != nullptr; 6639 const size_t num_interfaces = 6640 have_interfaces ? interfaces->GetLength() : klass->NumDirectInterfaces(); 6641 if (num_interfaces == 0) { 6642 if (super_ifcount == 0) { 6643 if (LIKELY(has_superclass)) { 6644 klass->SetIfTable(klass->GetSuperClass()->GetIfTable()); 6645 } 6646 // Class implements no interfaces. 6647 DCHECK_EQ(klass->GetIfTableCount(), 0); 6648 return true; 6649 } 6650 // Class implements same interfaces as parent, are any of these not marker interfaces? 6651 bool has_non_marker_interface = false; 6652 ObjPtr<mirror::IfTable> super_iftable = klass->GetSuperClass()->GetIfTable(); 6653 for (size_t i = 0; i < super_ifcount; ++i) { 6654 if (super_iftable->GetMethodArrayCount(i) > 0) { 6655 has_non_marker_interface = true; 6656 break; 6657 } 6658 } 6659 // Class just inherits marker interfaces from parent so recycle parent's iftable. 6660 if (!has_non_marker_interface) { 6661 klass->SetIfTable(super_iftable); 6662 return true; 6663 } 6664 } 6665 size_t ifcount = super_ifcount + num_interfaces; 6666 // Check that every class being implemented is an interface. 6667 for (size_t i = 0; i < num_interfaces; i++) { 6668 ObjPtr<mirror::Class> interface = have_interfaces 6669 ? interfaces->GetWithoutChecks(i) 6670 : mirror::Class::GetDirectInterface(self, klass.Get(), i); 6671 DCHECK(interface != nullptr); 6672 if (UNLIKELY(!interface->IsInterface())) { 6673 std::string temp; 6674 ThrowIncompatibleClassChangeError(klass.Get(), 6675 "Class %s implements non-interface class %s", 6676 klass->PrettyDescriptor().c_str(), 6677 PrettyDescriptor(interface->GetDescriptor(&temp)).c_str()); 6678 return false; 6679 } 6680 ifcount += interface->GetIfTableCount(); 6681 } 6682 // Create the interface function table. 6683 MutableHandle<mirror::IfTable> iftable(hs.NewHandle(AllocIfTable(self, ifcount))); 6684 if (UNLIKELY(iftable == nullptr)) { 6685 self->AssertPendingOOMException(); 6686 return false; 6687 } 6688 // Fill in table with superclass's iftable. 6689 if (super_ifcount != 0) { 6690 ObjPtr<mirror::IfTable> super_iftable = klass->GetSuperClass()->GetIfTable(); 6691 for (size_t i = 0; i < super_ifcount; i++) { 6692 ObjPtr<mirror::Class> super_interface = super_iftable->GetInterface(i); 6693 iftable->SetInterface(i, super_interface); 6694 } 6695 } 6696 6697 // Note that AllowThreadSuspension is to thread suspension as pthread_testcancel is to pthread 6698 // cancellation. That is it will suspend if one has a pending suspend request but otherwise 6699 // doesn't really do anything. 6700 self->AllowThreadSuspension(); 6701 6702 size_t new_ifcount; 6703 { 6704 ScopedAssertNoThreadSuspension nts("Copying mirror::Class*'s for FillIfTable"); 6705 std::vector<mirror::Class*> to_add; 6706 for (size_t i = 0; i < num_interfaces; i++) { 6707 ObjPtr<mirror::Class> interface = have_interfaces ? interfaces->Get(i) : 6708 mirror::Class::GetDirectInterface(self, klass.Get(), i); 6709 to_add.push_back(interface.Ptr()); 6710 } 6711 6712 new_ifcount = FillIfTable(iftable.Get(), super_ifcount, std::move(to_add)); 6713 } 6714 6715 self->AllowThreadSuspension(); 6716 6717 // Shrink iftable in case duplicates were found 6718 if (new_ifcount < ifcount) { 6719 DCHECK_NE(num_interfaces, 0U); 6720 iftable.Assign(down_cast<mirror::IfTable*>( 6721 iftable->CopyOf(self, new_ifcount * mirror::IfTable::kMax))); 6722 if (UNLIKELY(iftable == nullptr)) { 6723 self->AssertPendingOOMException(); 6724 return false; 6725 } 6726 ifcount = new_ifcount; 6727 } else { 6728 DCHECK_EQ(new_ifcount, ifcount); 6729 } 6730 klass->SetIfTable(iftable.Get()); 6731 return true; 6732 } 6733 6734 // Finds the method with a name/signature that matches cmp in the given lists of methods. The list 6735 // of methods must be unique. 6736 static ArtMethod* FindSameNameAndSignature(MethodNameAndSignatureComparator& cmp ATTRIBUTE_UNUSED) { 6737 return nullptr; 6738 } 6739 6740 template <typename ... Types> 6741 static ArtMethod* FindSameNameAndSignature(MethodNameAndSignatureComparator& cmp, 6742 const ScopedArenaVector<ArtMethod*>& list, 6743 const Types& ... rest) 6744 REQUIRES_SHARED(Locks::mutator_lock_) { 6745 for (ArtMethod* method : list) { 6746 if (cmp.HasSameNameAndSignature(method)) { 6747 return method; 6748 } 6749 } 6750 return FindSameNameAndSignature(cmp, rest...); 6751 } 6752 6753 // Check that all vtable entries are present in this class's virtuals or are the same as a 6754 // superclasses vtable entry. 6755 static void CheckClassOwnsVTableEntries(Thread* self, 6756 Handle<mirror::Class> klass, 6757 PointerSize pointer_size) 6758 REQUIRES_SHARED(Locks::mutator_lock_) { 6759 StackHandleScope<2> hs(self); 6760 Handle<mirror::PointerArray> check_vtable(hs.NewHandle(klass->GetVTableDuringLinking())); 6761 ObjPtr<mirror::Class> super_temp = (klass->HasSuperClass()) ? klass->GetSuperClass() : nullptr; 6762 Handle<mirror::Class> superclass(hs.NewHandle(super_temp)); 6763 int32_t super_vtable_length = (superclass != nullptr) ? superclass->GetVTableLength() : 0; 6764 for (int32_t i = 0; i < check_vtable->GetLength(); ++i) { 6765 ArtMethod* m = check_vtable->GetElementPtrSize<ArtMethod*>(i, pointer_size); 6766 CHECK(m != nullptr); 6767 6768 if (m->GetMethodIndexDuringLinking() != i) { 6769 LOG(WARNING) << m->PrettyMethod() 6770 << " has an unexpected method index for its spot in the vtable for class" 6771 << klass->PrettyClass(); 6772 } 6773 ArraySlice<ArtMethod> virtuals = klass->GetVirtualMethodsSliceUnchecked(pointer_size); 6774 auto is_same_method = [m] (const ArtMethod& meth) { 6775 return &meth == m; 6776 }; 6777 if (!((super_vtable_length > i && superclass->GetVTableEntry(i, pointer_size) == m) || 6778 std::find_if(virtuals.begin(), virtuals.end(), is_same_method) != virtuals.end())) { 6779 LOG(WARNING) << m->PrettyMethod() << " does not seem to be owned by current class " 6780 << klass->PrettyClass() << " or any of its superclasses!"; 6781 } 6782 } 6783 } 6784 6785 // Check to make sure the vtable does not have duplicates. Duplicates could cause problems when a 6786 // method is overridden in a subclass. 6787 static void CheckVTableHasNoDuplicates(Thread* self, 6788 Handle<mirror::Class> klass, 6789 PointerSize pointer_size) 6790 REQUIRES_SHARED(Locks::mutator_lock_) { 6791 StackHandleScope<1> hs(self); 6792 Handle<mirror::PointerArray> vtable(hs.NewHandle(klass->GetVTableDuringLinking())); 6793 int32_t num_entries = vtable->GetLength(); 6794 for (int32_t i = 0; i < num_entries; i++) { 6795 ArtMethod* vtable_entry = vtable->GetElementPtrSize<ArtMethod*>(i, pointer_size); 6796 // Don't bother if we cannot 'see' the vtable entry (i.e. it is a package-private member maybe). 6797 if (!klass->CanAccessMember(vtable_entry->GetDeclaringClass(), 6798 vtable_entry->GetAccessFlags())) { 6799 continue; 6800 } 6801 MethodNameAndSignatureComparator name_comparator( 6802 vtable_entry->GetInterfaceMethodIfProxy(pointer_size)); 6803 for (int32_t j = i + 1; j < num_entries; j++) { 6804 ArtMethod* other_entry = vtable->GetElementPtrSize<ArtMethod*>(j, pointer_size); 6805 if (!klass->CanAccessMember(other_entry->GetDeclaringClass(), 6806 other_entry->GetAccessFlags())) { 6807 continue; 6808 } 6809 if (vtable_entry == other_entry || 6810 name_comparator.HasSameNameAndSignature( 6811 other_entry->GetInterfaceMethodIfProxy(pointer_size))) { 6812 LOG(WARNING) << "vtable entries " << i << " and " << j << " are identical for " 6813 << klass->PrettyClass() << " in method " << vtable_entry->PrettyMethod() 6814 << " (0x" << std::hex << reinterpret_cast<uintptr_t>(vtable_entry) << ") and " 6815 << other_entry->PrettyMethod() << " (0x" << std::hex 6816 << reinterpret_cast<uintptr_t>(other_entry) << ")"; 6817 } 6818 } 6819 } 6820 } 6821 6822 static void SanityCheckVTable(Thread* self, Handle<mirror::Class> klass, PointerSize pointer_size) 6823 REQUIRES_SHARED(Locks::mutator_lock_) { 6824 CheckClassOwnsVTableEntries(self, klass, pointer_size); 6825 CheckVTableHasNoDuplicates(self, klass, pointer_size); 6826 } 6827 6828 void ClassLinker::FillImtFromSuperClass(Handle<mirror::Class> klass, 6829 ArtMethod* unimplemented_method, 6830 ArtMethod* imt_conflict_method, 6831 bool* new_conflict, 6832 ArtMethod** imt) { 6833 DCHECK(klass->HasSuperClass()); 6834 ObjPtr<mirror::Class> super_class = klass->GetSuperClass(); 6835 if (super_class->ShouldHaveImt()) { 6836 ImTable* super_imt = super_class->GetImt(image_pointer_size_); 6837 for (size_t i = 0; i < ImTable::kSize; ++i) { 6838 imt[i] = super_imt->Get(i, image_pointer_size_); 6839 } 6840 } else { 6841 // No imt in the super class, need to reconstruct from the iftable. 6842 ObjPtr<mirror::IfTable> if_table = super_class->GetIfTable(); 6843 if (if_table->Count() != 0) { 6844 // Ignore copied methods since we will handle these in LinkInterfaceMethods. 6845 FillIMTFromIfTable(if_table, 6846 unimplemented_method, 6847 imt_conflict_method, 6848 klass.Get(), 6849 /*create_conflict_table*/false, 6850 /*ignore_copied_methods*/true, 6851 /*out*/new_conflict, 6852 /*out*/imt); 6853 } 6854 } 6855 } 6856 6857 class ClassLinker::LinkInterfaceMethodsHelper { 6858 public: 6859 LinkInterfaceMethodsHelper(ClassLinker* class_linker, 6860 Handle<mirror::Class> klass, 6861 Thread* self, 6862 Runtime* runtime) 6863 : class_linker_(class_linker), 6864 klass_(klass), 6865 method_alignment_(ArtMethod::Alignment(class_linker->GetImagePointerSize())), 6866 method_size_(ArtMethod::Size(class_linker->GetImagePointerSize())), 6867 self_(self), 6868 stack_(runtime->GetLinearAlloc()->GetArenaPool()), 6869 allocator_(&stack_), 6870 default_conflict_methods_(allocator_.Adapter()), 6871 overriding_default_conflict_methods_(allocator_.Adapter()), 6872 miranda_methods_(allocator_.Adapter()), 6873 default_methods_(allocator_.Adapter()), 6874 overriding_default_methods_(allocator_.Adapter()), 6875 move_table_(allocator_.Adapter()) { 6876 } 6877 6878 ArtMethod* FindMethod(ArtMethod* interface_method, 6879 MethodNameAndSignatureComparator& interface_name_comparator, 6880 ArtMethod* vtable_impl) 6881 REQUIRES_SHARED(Locks::mutator_lock_); 6882 6883 ArtMethod* GetOrCreateMirandaMethod(ArtMethod* interface_method, 6884 MethodNameAndSignatureComparator& interface_name_comparator) 6885 REQUIRES_SHARED(Locks::mutator_lock_); 6886 6887 bool HasNewVirtuals() const { 6888 return !(miranda_methods_.empty() && 6889 default_methods_.empty() && 6890 overriding_default_methods_.empty() && 6891 overriding_default_conflict_methods_.empty() && 6892 default_conflict_methods_.empty()); 6893 } 6894 6895 void ReallocMethods() REQUIRES_SHARED(Locks::mutator_lock_); 6896 6897 ObjPtr<mirror::PointerArray> UpdateVtable( 6898 const std::unordered_map<size_t, ClassLinker::MethodTranslation>& default_translations, 6899 ObjPtr<mirror::PointerArray> old_vtable) REQUIRES_SHARED(Locks::mutator_lock_); 6900 6901 void UpdateIfTable(Handle<mirror::IfTable> iftable) REQUIRES_SHARED(Locks::mutator_lock_); 6902 6903 void UpdateIMT(ArtMethod** out_imt); 6904 6905 void CheckNoStaleMethodsInDexCache() REQUIRES_SHARED(Locks::mutator_lock_) { 6906 if (kIsDebugBuild) { 6907 PointerSize pointer_size = class_linker_->GetImagePointerSize(); 6908 // Check that there are no stale methods are in the dex cache array. 6909 auto* resolved_methods = klass_->GetDexCache()->GetResolvedMethods(); 6910 for (size_t i = 0, count = klass_->GetDexCache()->NumResolvedMethods(); i < count; ++i) { 6911 auto pair = mirror::DexCache::GetNativePairPtrSize(resolved_methods, i, pointer_size); 6912 ArtMethod* m = pair.object; 6913 CHECK(move_table_.find(m) == move_table_.end() || 6914 // The original versions of copied methods will still be present so allow those too. 6915 // Note that if the first check passes this might fail to GetDeclaringClass(). 6916 std::find_if(m->GetDeclaringClass()->GetMethods(pointer_size).begin(), 6917 m->GetDeclaringClass()->GetMethods(pointer_size).end(), 6918 [m] (ArtMethod& meth) { 6919 return &meth == m; 6920 }) != m->GetDeclaringClass()->GetMethods(pointer_size).end()) 6921 << "Obsolete method " << m->PrettyMethod() << " is in dex cache!"; 6922 } 6923 } 6924 } 6925 6926 void ClobberOldMethods(LengthPrefixedArray<ArtMethod>* old_methods, 6927 LengthPrefixedArray<ArtMethod>* methods) { 6928 if (kIsDebugBuild) { 6929 CHECK(methods != nullptr); 6930 // Put some random garbage in old methods to help find stale pointers. 6931 if (methods != old_methods && old_methods != nullptr) { 6932 // Need to make sure the GC is not running since it could be scanning the methods we are 6933 // about to overwrite. 6934 ScopedThreadStateChange tsc(self_, kSuspended); 6935 gc::ScopedGCCriticalSection gcs(self_, 6936 gc::kGcCauseClassLinker, 6937 gc::kCollectorTypeClassLinker); 6938 const size_t old_size = LengthPrefixedArray<ArtMethod>::ComputeSize(old_methods->size(), 6939 method_size_, 6940 method_alignment_); 6941 memset(old_methods, 0xFEu, old_size); 6942 } 6943 } 6944 } 6945 6946 private: 6947 size_t NumberOfNewVirtuals() const { 6948 return miranda_methods_.size() + 6949 default_methods_.size() + 6950 overriding_default_conflict_methods_.size() + 6951 overriding_default_methods_.size() + 6952 default_conflict_methods_.size(); 6953 } 6954 6955 bool FillTables() REQUIRES_SHARED(Locks::mutator_lock_) { 6956 return !klass_->IsInterface(); 6957 } 6958 6959 void LogNewVirtuals() const REQUIRES_SHARED(Locks::mutator_lock_) { 6960 DCHECK(!klass_->IsInterface() || (default_methods_.empty() && miranda_methods_.empty())) 6961 << "Interfaces should only have default-conflict methods appended to them."; 6962 VLOG(class_linker) << mirror::Class::PrettyClass(klass_.Get()) << ": miranda_methods=" 6963 << miranda_methods_.size() 6964 << " default_methods=" << default_methods_.size() 6965 << " overriding_default_methods=" << overriding_default_methods_.size() 6966 << " default_conflict_methods=" << default_conflict_methods_.size() 6967 << " overriding_default_conflict_methods=" 6968 << overriding_default_conflict_methods_.size(); 6969 } 6970 6971 ClassLinker* class_linker_; 6972 Handle<mirror::Class> klass_; 6973 size_t method_alignment_; 6974 size_t method_size_; 6975 Thread* const self_; 6976 6977 // These are allocated on the heap to begin, we then transfer to linear alloc when we re-create 6978 // the virtual methods array. 6979 // Need to use low 4GB arenas for compiler or else the pointers wont fit in 32 bit method array 6980 // during cross compilation. 6981 // Use the linear alloc pool since this one is in the low 4gb for the compiler. 6982 ArenaStack stack_; 6983 ScopedArenaAllocator allocator_; 6984 6985 ScopedArenaVector<ArtMethod*> default_conflict_methods_; 6986 ScopedArenaVector<ArtMethod*> overriding_default_conflict_methods_; 6987 ScopedArenaVector<ArtMethod*> miranda_methods_; 6988 ScopedArenaVector<ArtMethod*> default_methods_; 6989 ScopedArenaVector<ArtMethod*> overriding_default_methods_; 6990 6991 ScopedArenaUnorderedMap<ArtMethod*, ArtMethod*> move_table_; 6992 }; 6993 6994 ArtMethod* ClassLinker::LinkInterfaceMethodsHelper::FindMethod( 6995 ArtMethod* interface_method, 6996 MethodNameAndSignatureComparator& interface_name_comparator, 6997 ArtMethod* vtable_impl) { 6998 ArtMethod* current_method = nullptr; 6999 switch (class_linker_->FindDefaultMethodImplementation(self_, 7000 interface_method, 7001 klass_, 7002 /*out*/¤t_method)) { 7003 case DefaultMethodSearchResult::kDefaultConflict: { 7004 // Default method conflict. 7005 DCHECK(current_method == nullptr); 7006 ArtMethod* default_conflict_method = nullptr; 7007 if (vtable_impl != nullptr && vtable_impl->IsDefaultConflicting()) { 7008 // We can reuse the method from the superclass, don't bother adding it to virtuals. 7009 default_conflict_method = vtable_impl; 7010 } else { 7011 // See if we already have a conflict method for this method. 7012 ArtMethod* preexisting_conflict = FindSameNameAndSignature( 7013 interface_name_comparator, 7014 default_conflict_methods_, 7015 overriding_default_conflict_methods_); 7016 if (LIKELY(preexisting_conflict != nullptr)) { 7017 // We already have another conflict we can reuse. 7018 default_conflict_method = preexisting_conflict; 7019 } else { 7020 // Note that we do this even if we are an interface since we need to create this and 7021 // cannot reuse another classes. 7022 // Create a new conflict method for this to use. 7023 default_conflict_method = reinterpret_cast<ArtMethod*>(allocator_.Alloc(method_size_)); 7024 new(default_conflict_method) ArtMethod(interface_method, 7025 class_linker_->GetImagePointerSize()); 7026 if (vtable_impl == nullptr) { 7027 // Save the conflict method. We need to add it to the vtable. 7028 default_conflict_methods_.push_back(default_conflict_method); 7029 } else { 7030 // Save the conflict method but it is already in the vtable. 7031 overriding_default_conflict_methods_.push_back(default_conflict_method); 7032 } 7033 } 7034 } 7035 current_method = default_conflict_method; 7036 break; 7037 } // case kDefaultConflict 7038 case DefaultMethodSearchResult::kDefaultFound: { 7039 DCHECK(current_method != nullptr); 7040 // Found a default method. 7041 if (vtable_impl != nullptr && 7042 current_method->GetDeclaringClass() == vtable_impl->GetDeclaringClass()) { 7043 // We found a default method but it was the same one we already have from our 7044 // superclass. Don't bother adding it to our vtable again. 7045 current_method = vtable_impl; 7046 } else if (LIKELY(FillTables())) { 7047 // Interfaces don't need to copy default methods since they don't have vtables. 7048 // Only record this default method if it is new to save space. 7049 // TODO It might be worthwhile to copy default methods on interfaces anyway since it 7050 // would make lookup for interface super much faster. (We would only need to scan 7051 // the iftable to find if there is a NSME or AME.) 7052 ArtMethod* old = FindSameNameAndSignature(interface_name_comparator, 7053 default_methods_, 7054 overriding_default_methods_); 7055 if (old == nullptr) { 7056 // We found a default method implementation and there were no conflicts. 7057 if (vtable_impl == nullptr) { 7058 // Save the default method. We need to add it to the vtable. 7059 default_methods_.push_back(current_method); 7060 } else { 7061 // Save the default method but it is already in the vtable. 7062 overriding_default_methods_.push_back(current_method); 7063 } 7064 } else { 7065 CHECK(old == current_method) << "Multiple default implementations selected!"; 7066 } 7067 } 7068 break; 7069 } // case kDefaultFound 7070 case DefaultMethodSearchResult::kAbstractFound: { 7071 DCHECK(current_method == nullptr); 7072 // Abstract method masks all defaults. 7073 if (vtable_impl != nullptr && 7074 vtable_impl->IsAbstract() && 7075 !vtable_impl->IsDefaultConflicting()) { 7076 // We need to make this an abstract method but the version in the vtable already is so 7077 // don't do anything. 7078 current_method = vtable_impl; 7079 } 7080 break; 7081 } // case kAbstractFound 7082 } 7083 return current_method; 7084 } 7085 7086 ArtMethod* ClassLinker::LinkInterfaceMethodsHelper::GetOrCreateMirandaMethod( 7087 ArtMethod* interface_method, 7088 MethodNameAndSignatureComparator& interface_name_comparator) { 7089 // Find out if there is already a miranda method we can use. 7090 ArtMethod* miranda_method = FindSameNameAndSignature(interface_name_comparator, 7091 miranda_methods_); 7092 if (miranda_method == nullptr) { 7093 DCHECK(interface_method->IsAbstract()) << interface_method->PrettyMethod(); 7094 miranda_method = reinterpret_cast<ArtMethod*>(allocator_.Alloc(method_size_)); 7095 CHECK(miranda_method != nullptr); 7096 // Point the interface table at a phantom slot. 7097 new(miranda_method) ArtMethod(interface_method, class_linker_->GetImagePointerSize()); 7098 miranda_methods_.push_back(miranda_method); 7099 } 7100 return miranda_method; 7101 } 7102 7103 void ClassLinker::LinkInterfaceMethodsHelper::ReallocMethods() { 7104 LogNewVirtuals(); 7105 7106 const size_t old_method_count = klass_->NumMethods(); 7107 const size_t new_method_count = old_method_count + NumberOfNewVirtuals(); 7108 DCHECK_NE(old_method_count, new_method_count); 7109 7110 // Attempt to realloc to save RAM if possible. 7111 LengthPrefixedArray<ArtMethod>* old_methods = klass_->GetMethodsPtr(); 7112 // The Realloced virtual methods aren't visible from the class roots, so there is no issue 7113 // where GCs could attempt to mark stale pointers due to memcpy. And since we overwrite the 7114 // realloced memory with out->CopyFrom, we are guaranteed to have objects in the to space since 7115 // CopyFrom has internal read barriers. 7116 // 7117 // TODO We should maybe move some of this into mirror::Class or at least into another method. 7118 const size_t old_size = LengthPrefixedArray<ArtMethod>::ComputeSize(old_method_count, 7119 method_size_, 7120 method_alignment_); 7121 const size_t new_size = LengthPrefixedArray<ArtMethod>::ComputeSize(new_method_count, 7122 method_size_, 7123 method_alignment_); 7124 const size_t old_methods_ptr_size = (old_methods != nullptr) ? old_size : 0; 7125 auto* methods = reinterpret_cast<LengthPrefixedArray<ArtMethod>*>( 7126 class_linker_->GetAllocatorForClassLoader(klass_->GetClassLoader())->Realloc( 7127 self_, old_methods, old_methods_ptr_size, new_size)); 7128 CHECK(methods != nullptr); // Native allocation failure aborts. 7129 7130 PointerSize pointer_size = class_linker_->GetImagePointerSize(); 7131 if (methods != old_methods) { 7132 // Maps from heap allocated miranda method to linear alloc miranda method. 7133 StrideIterator<ArtMethod> out = methods->begin(method_size_, method_alignment_); 7134 // Copy over the old methods. 7135 for (auto& m : klass_->GetMethods(pointer_size)) { 7136 move_table_.emplace(&m, &*out); 7137 // The CopyFrom is only necessary to not miss read barriers since Realloc won't do read 7138 // barriers when it copies. 7139 out->CopyFrom(&m, pointer_size); 7140 ++out; 7141 } 7142 } 7143 StrideIterator<ArtMethod> out(methods->begin(method_size_, method_alignment_) + old_method_count); 7144 // Copy over miranda methods before copying vtable since CopyOf may cause thread suspension and 7145 // we want the roots of the miranda methods to get visited. 7146 for (size_t i = 0; i < miranda_methods_.size(); ++i) { 7147 ArtMethod* mir_method = miranda_methods_[i]; 7148 ArtMethod& new_method = *out; 7149 new_method.CopyFrom(mir_method, pointer_size); 7150 new_method.SetAccessFlags(new_method.GetAccessFlags() | kAccMiranda | kAccCopied); 7151 DCHECK_NE(new_method.GetAccessFlags() & kAccAbstract, 0u) 7152 << "Miranda method should be abstract!"; 7153 move_table_.emplace(mir_method, &new_method); 7154 // Update the entry in the method array, as the array will be used for future lookups, 7155 // where thread suspension is allowed. 7156 // As such, the array should not contain locally allocated ArtMethod, otherwise the GC 7157 // would not see them. 7158 miranda_methods_[i] = &new_method; 7159 ++out; 7160 } 7161 // We need to copy the default methods into our own method table since the runtime requires that 7162 // every method on a class's vtable be in that respective class's virtual method table. 7163 // NOTE This means that two classes might have the same implementation of a method from the same 7164 // interface but will have different ArtMethod*s for them. This also means we cannot compare a 7165 // default method found on a class with one found on the declaring interface directly and must 7166 // look at the declaring class to determine if they are the same. 7167 for (ScopedArenaVector<ArtMethod*>* methods_vec : {&default_methods_, 7168 &overriding_default_methods_}) { 7169 for (size_t i = 0; i < methods_vec->size(); ++i) { 7170 ArtMethod* def_method = (*methods_vec)[i]; 7171 ArtMethod& new_method = *out; 7172 new_method.CopyFrom(def_method, pointer_size); 7173 // Clear the kAccSkipAccessChecks flag if it is present. Since this class hasn't been 7174 // verified yet it shouldn't have methods that are skipping access checks. 7175 // TODO This is rather arbitrary. We should maybe support classes where only some of its 7176 // methods are skip_access_checks. 7177 constexpr uint32_t kSetFlags = kAccDefault | kAccCopied; 7178 constexpr uint32_t kMaskFlags = ~kAccSkipAccessChecks; 7179 new_method.SetAccessFlags((new_method.GetAccessFlags() | kSetFlags) & kMaskFlags); 7180 move_table_.emplace(def_method, &new_method); 7181 // Update the entry in the method array, as the array will be used for future lookups, 7182 // where thread suspension is allowed. 7183 // As such, the array should not contain locally allocated ArtMethod, otherwise the GC 7184 // would not see them. 7185 (*methods_vec)[i] = &new_method; 7186 ++out; 7187 } 7188 } 7189 for (ScopedArenaVector<ArtMethod*>* methods_vec : {&default_conflict_methods_, 7190 &overriding_default_conflict_methods_}) { 7191 for (size_t i = 0; i < methods_vec->size(); ++i) { 7192 ArtMethod* conf_method = (*methods_vec)[i]; 7193 ArtMethod& new_method = *out; 7194 new_method.CopyFrom(conf_method, pointer_size); 7195 // This is a type of default method (there are default method impls, just a conflict) so 7196 // mark this as a default, non-abstract method, since thats what it is. Also clear the 7197 // kAccSkipAccessChecks bit since this class hasn't been verified yet it shouldn't have 7198 // methods that are skipping access checks. 7199 constexpr uint32_t kSetFlags = kAccDefault | kAccDefaultConflict | kAccCopied; 7200 constexpr uint32_t kMaskFlags = ~(kAccAbstract | kAccSkipAccessChecks); 7201 new_method.SetAccessFlags((new_method.GetAccessFlags() | kSetFlags) & kMaskFlags); 7202 DCHECK(new_method.IsDefaultConflicting()); 7203 // The actual method might or might not be marked abstract since we just copied it from a 7204 // (possibly default) interface method. We need to set it entry point to be the bridge so 7205 // that the compiler will not invoke the implementation of whatever method we copied from. 7206 EnsureThrowsInvocationError(class_linker_, &new_method); 7207 move_table_.emplace(conf_method, &new_method); 7208 // Update the entry in the method array, as the array will be used for future lookups, 7209 // where thread suspension is allowed. 7210 // As such, the array should not contain locally allocated ArtMethod, otherwise the GC 7211 // would not see them. 7212 (*methods_vec)[i] = &new_method; 7213 ++out; 7214 } 7215 } 7216 methods->SetSize(new_method_count); 7217 class_linker_->UpdateClassMethods(klass_.Get(), methods); 7218 } 7219 7220 ObjPtr<mirror::PointerArray> ClassLinker::LinkInterfaceMethodsHelper::UpdateVtable( 7221 const std::unordered_map<size_t, ClassLinker::MethodTranslation>& default_translations, 7222 ObjPtr<mirror::PointerArray> old_vtable) { 7223 // Update the vtable to the new method structures. We can skip this for interfaces since they 7224 // do not have vtables. 7225 const size_t old_vtable_count = old_vtable->GetLength(); 7226 const size_t new_vtable_count = old_vtable_count + 7227 miranda_methods_.size() + 7228 default_methods_.size() + 7229 default_conflict_methods_.size(); 7230 7231 ObjPtr<mirror::PointerArray> vtable = 7232 down_cast<mirror::PointerArray*>(old_vtable->CopyOf(self_, new_vtable_count)); 7233 if (UNLIKELY(vtable == nullptr)) { 7234 self_->AssertPendingOOMException(); 7235 return nullptr; 7236 } 7237 7238 size_t vtable_pos = old_vtable_count; 7239 PointerSize pointer_size = class_linker_->GetImagePointerSize(); 7240 // Update all the newly copied method's indexes so they denote their placement in the vtable. 7241 for (const ScopedArenaVector<ArtMethod*>& methods_vec : {default_methods_, 7242 default_conflict_methods_, 7243 miranda_methods_}) { 7244 // These are the functions that are not already in the vtable! 7245 for (ArtMethod* new_vtable_method : methods_vec) { 7246 // Leave the declaring class alone the method's dex_code_item_offset_ and dex_method_index_ 7247 // fields are references into the dex file the method was defined in. Since the ArtMethod 7248 // does not store that information it uses declaring_class_->dex_cache_. 7249 new_vtable_method->SetMethodIndex(0xFFFF & vtable_pos); 7250 vtable->SetElementPtrSize(vtable_pos, new_vtable_method, pointer_size); 7251 ++vtable_pos; 7252 } 7253 } 7254 DCHECK_EQ(vtable_pos, new_vtable_count); 7255 7256 // Update old vtable methods. We use the default_translations map to figure out what each 7257 // vtable entry should be updated to, if they need to be at all. 7258 for (size_t i = 0; i < old_vtable_count; ++i) { 7259 ArtMethod* translated_method = vtable->GetElementPtrSize<ArtMethod*>(i, pointer_size); 7260 // Try and find what we need to change this method to. 7261 auto translation_it = default_translations.find(i); 7262 if (translation_it != default_translations.end()) { 7263 if (translation_it->second.IsInConflict()) { 7264 // Find which conflict method we are to use for this method. 7265 MethodNameAndSignatureComparator old_method_comparator( 7266 translated_method->GetInterfaceMethodIfProxy(pointer_size)); 7267 // We only need to look through overriding_default_conflict_methods since this is an 7268 // overridden method we are fixing up here. 7269 ArtMethod* new_conflict_method = FindSameNameAndSignature( 7270 old_method_comparator, overriding_default_conflict_methods_); 7271 CHECK(new_conflict_method != nullptr) << "Expected a conflict method!"; 7272 translated_method = new_conflict_method; 7273 } else if (translation_it->second.IsAbstract()) { 7274 // Find which miranda method we are to use for this method. 7275 MethodNameAndSignatureComparator old_method_comparator( 7276 translated_method->GetInterfaceMethodIfProxy(pointer_size)); 7277 ArtMethod* miranda_method = FindSameNameAndSignature(old_method_comparator, 7278 miranda_methods_); 7279 DCHECK(miranda_method != nullptr); 7280 translated_method = miranda_method; 7281 } else { 7282 // Normal default method (changed from an older default or abstract interface method). 7283 DCHECK(translation_it->second.IsTranslation()); 7284 translated_method = translation_it->second.GetTranslation(); 7285 auto it = move_table_.find(translated_method); 7286 DCHECK(it != move_table_.end()); 7287 translated_method = it->second; 7288 } 7289 } else { 7290 auto it = move_table_.find(translated_method); 7291 translated_method = (it != move_table_.end()) ? it->second : nullptr; 7292 } 7293 7294 if (translated_method != nullptr) { 7295 // Make sure the new_methods index is set. 7296 if (translated_method->GetMethodIndexDuringLinking() != i) { 7297 if (kIsDebugBuild) { 7298 auto* methods = klass_->GetMethodsPtr(); 7299 CHECK_LE(reinterpret_cast<uintptr_t>(&*methods->begin(method_size_, method_alignment_)), 7300 reinterpret_cast<uintptr_t>(translated_method)); 7301 CHECK_LT(reinterpret_cast<uintptr_t>(translated_method), 7302 reinterpret_cast<uintptr_t>(&*methods->end(method_size_, method_alignment_))); 7303 } 7304 translated_method->SetMethodIndex(0xFFFF & i); 7305 } 7306 vtable->SetElementPtrSize(i, translated_method, pointer_size); 7307 } 7308 } 7309 klass_->SetVTable(vtable.Ptr()); 7310 return vtable; 7311 } 7312 7313 void ClassLinker::LinkInterfaceMethodsHelper::UpdateIfTable(Handle<mirror::IfTable> iftable) { 7314 PointerSize pointer_size = class_linker_->GetImagePointerSize(); 7315 const size_t ifcount = klass_->GetIfTableCount(); 7316 // Go fix up all the stale iftable pointers. 7317 for (size_t i = 0; i < ifcount; ++i) { 7318 for (size_t j = 0, count = iftable->GetMethodArrayCount(i); j < count; ++j) { 7319 auto* method_array = iftable->GetMethodArray(i); 7320 auto* m = method_array->GetElementPtrSize<ArtMethod*>(j, pointer_size); 7321 DCHECK(m != nullptr) << klass_->PrettyClass(); 7322 auto it = move_table_.find(m); 7323 if (it != move_table_.end()) { 7324 auto* new_m = it->second; 7325 DCHECK(new_m != nullptr) << klass_->PrettyClass(); 7326 method_array->SetElementPtrSize(j, new_m, pointer_size); 7327 } 7328 } 7329 } 7330 } 7331 7332 void ClassLinker::LinkInterfaceMethodsHelper::UpdateIMT(ArtMethod** out_imt) { 7333 // Fix up IMT next. 7334 for (size_t i = 0; i < ImTable::kSize; ++i) { 7335 auto it = move_table_.find(out_imt[i]); 7336 if (it != move_table_.end()) { 7337 out_imt[i] = it->second; 7338 } 7339 } 7340 } 7341 7342 // TODO This method needs to be split up into several smaller methods. 7343 bool ClassLinker::LinkInterfaceMethods( 7344 Thread* self, 7345 Handle<mirror::Class> klass, 7346 const std::unordered_map<size_t, ClassLinker::MethodTranslation>& default_translations, 7347 bool* out_new_conflict, 7348 ArtMethod** out_imt) { 7349 StackHandleScope<3> hs(self); 7350 Runtime* const runtime = Runtime::Current(); 7351 7352 const bool is_interface = klass->IsInterface(); 7353 const bool has_superclass = klass->HasSuperClass(); 7354 const bool fill_tables = !is_interface; 7355 const size_t super_ifcount = has_superclass ? klass->GetSuperClass()->GetIfTableCount() : 0U; 7356 const size_t ifcount = klass->GetIfTableCount(); 7357 7358 Handle<mirror::IfTable> iftable(hs.NewHandle(klass->GetIfTable())); 7359 7360 MutableHandle<mirror::PointerArray> vtable(hs.NewHandle(klass->GetVTableDuringLinking())); 7361 ArtMethod* const unimplemented_method = runtime->GetImtUnimplementedMethod(); 7362 ArtMethod* const imt_conflict_method = runtime->GetImtConflictMethod(); 7363 // Copy the IMT from the super class if possible. 7364 const bool extend_super_iftable = has_superclass; 7365 if (has_superclass && fill_tables) { 7366 FillImtFromSuperClass(klass, 7367 unimplemented_method, 7368 imt_conflict_method, 7369 out_new_conflict, 7370 out_imt); 7371 } 7372 // Allocate method arrays before since we don't want miss visiting miranda method roots due to 7373 // thread suspension. 7374 if (fill_tables) { 7375 if (!AllocateIfTableMethodArrays(self, klass, iftable)) { 7376 return false; 7377 } 7378 } 7379 7380 LinkInterfaceMethodsHelper helper(this, klass, self, runtime); 7381 7382 auto* old_cause = self->StartAssertNoThreadSuspension( 7383 "Copying ArtMethods for LinkInterfaceMethods"); 7384 // Going in reverse to ensure that we will hit abstract methods that override defaults before the 7385 // defaults. This means we don't need to do any trickery when creating the Miranda methods, since 7386 // they will already be null. This has the additional benefit that the declarer of a miranda 7387 // method will actually declare an abstract method. 7388 for (size_t i = ifcount; i != 0u; ) { 7389 --i; 7390 DCHECK_LT(i, ifcount); 7391 7392 size_t num_methods = iftable->GetInterface(i)->NumDeclaredVirtualMethods(); 7393 if (num_methods > 0) { 7394 StackHandleScope<2> hs2(self); 7395 const bool is_super = i < super_ifcount; 7396 const bool super_interface = is_super && extend_super_iftable; 7397 // We don't actually create or fill these tables for interfaces, we just copy some methods for 7398 // conflict methods. Just set this as nullptr in those cases. 7399 Handle<mirror::PointerArray> method_array(fill_tables 7400 ? hs2.NewHandle(iftable->GetMethodArray(i)) 7401 : hs2.NewHandle<mirror::PointerArray>(nullptr)); 7402 7403 ArraySlice<ArtMethod> input_virtual_methods; 7404 ScopedNullHandle<mirror::PointerArray> null_handle; 7405 Handle<mirror::PointerArray> input_vtable_array(null_handle); 7406 int32_t input_array_length = 0; 7407 7408 // TODO Cleanup Needed: In the presence of default methods this optimization is rather dirty 7409 // and confusing. Default methods should always look through all the superclasses 7410 // because they are the last choice of an implementation. We get around this by looking 7411 // at the super-classes iftable methods (copied into method_array previously) when we are 7412 // looking for the implementation of a super-interface method but that is rather dirty. 7413 bool using_virtuals; 7414 if (super_interface || is_interface) { 7415 // If we are overwriting a super class interface, try to only virtual methods instead of the 7416 // whole vtable. 7417 using_virtuals = true; 7418 input_virtual_methods = klass->GetDeclaredMethodsSlice(image_pointer_size_); 7419 input_array_length = input_virtual_methods.size(); 7420 } else { 7421 // For a new interface, however, we need the whole vtable in case a new 7422 // interface method is implemented in the whole superclass. 7423 using_virtuals = false; 7424 DCHECK(vtable != nullptr); 7425 input_vtable_array = vtable; 7426 input_array_length = input_vtable_array->GetLength(); 7427 } 7428 7429 // For each method in interface 7430 for (size_t j = 0; j < num_methods; ++j) { 7431 auto* interface_method = iftable->GetInterface(i)->GetVirtualMethod(j, image_pointer_size_); 7432 MethodNameAndSignatureComparator interface_name_comparator( 7433 interface_method->GetInterfaceMethodIfProxy(image_pointer_size_)); 7434 uint32_t imt_index = ImTable::GetImtIndex(interface_method); 7435 ArtMethod** imt_ptr = &out_imt[imt_index]; 7436 // For each method listed in the interface's method list, find the 7437 // matching method in our class's method list. We want to favor the 7438 // subclass over the superclass, which just requires walking 7439 // back from the end of the vtable. (This only matters if the 7440 // superclass defines a private method and this class redefines 7441 // it -- otherwise it would use the same vtable slot. In .dex files 7442 // those don't end up in the virtual method table, so it shouldn't 7443 // matter which direction we go. We walk it backward anyway.) 7444 // 7445 // To find defaults we need to do the same but also go over interfaces. 7446 bool found_impl = false; 7447 ArtMethod* vtable_impl = nullptr; 7448 for (int32_t k = input_array_length - 1; k >= 0; --k) { 7449 ArtMethod* vtable_method = using_virtuals ? 7450 &input_virtual_methods[k] : 7451 input_vtable_array->GetElementPtrSize<ArtMethod*>(k, image_pointer_size_); 7452 ArtMethod* vtable_method_for_name_comparison = 7453 vtable_method->GetInterfaceMethodIfProxy(image_pointer_size_); 7454 if (interface_name_comparator.HasSameNameAndSignature( 7455 vtable_method_for_name_comparison)) { 7456 if (!vtable_method->IsAbstract() && !vtable_method->IsPublic()) { 7457 // Must do EndAssertNoThreadSuspension before throw since the throw can cause 7458 // allocations. 7459 self->EndAssertNoThreadSuspension(old_cause); 7460 ThrowIllegalAccessError(klass.Get(), 7461 "Method '%s' implementing interface method '%s' is not public", 7462 vtable_method->PrettyMethod().c_str(), 7463 interface_method->PrettyMethod().c_str()); 7464 return false; 7465 } else if (UNLIKELY(vtable_method->IsOverridableByDefaultMethod())) { 7466 // We might have a newer, better, default method for this, so we just skip it. If we 7467 // are still using this we will select it again when scanning for default methods. To 7468 // obviate the need to copy the method again we will make a note that we already found 7469 // a default here. 7470 // TODO This should be much cleaner. 7471 vtable_impl = vtable_method; 7472 break; 7473 } else { 7474 found_impl = true; 7475 if (LIKELY(fill_tables)) { 7476 method_array->SetElementPtrSize(j, vtable_method, image_pointer_size_); 7477 // Place method in imt if entry is empty, place conflict otherwise. 7478 SetIMTRef(unimplemented_method, 7479 imt_conflict_method, 7480 vtable_method, 7481 /*out*/out_new_conflict, 7482 /*out*/imt_ptr); 7483 } 7484 break; 7485 } 7486 } 7487 } 7488 // Continue on to the next method if we are done. 7489 if (LIKELY(found_impl)) { 7490 continue; 7491 } else if (LIKELY(super_interface)) { 7492 // Don't look for a default implementation when the super-method is implemented directly 7493 // by the class. 7494 // 7495 // See if we can use the superclasses method and skip searching everything else. 7496 // Note: !found_impl && super_interface 7497 CHECK(extend_super_iftable); 7498 // If this is a super_interface method it is possible we shouldn't override it because a 7499 // superclass could have implemented it directly. We get the method the superclass used 7500 // to implement this to know if we can override it with a default method. Doing this is 7501 // safe since we know that the super_iftable is filled in so we can simply pull it from 7502 // there. We don't bother if this is not a super-classes interface since in that case we 7503 // have scanned the entire vtable anyway and would have found it. 7504 // TODO This is rather dirty but it is faster than searching through the entire vtable 7505 // every time. 7506 ArtMethod* supers_method = 7507 method_array->GetElementPtrSize<ArtMethod*>(j, image_pointer_size_); 7508 DCHECK(supers_method != nullptr); 7509 DCHECK(interface_name_comparator.HasSameNameAndSignature(supers_method)); 7510 if (LIKELY(!supers_method->IsOverridableByDefaultMethod())) { 7511 // The method is not overridable by a default method (i.e. it is directly implemented 7512 // in some class). Therefore move onto the next interface method. 7513 continue; 7514 } else { 7515 // If the super-classes method is override-able by a default method we need to keep 7516 // track of it since though it is override-able it is not guaranteed to be 'overridden'. 7517 // If it turns out not to be overridden and we did not keep track of it we might add it 7518 // to the vtable twice, causing corruption (vtable entries having inconsistent and 7519 // illegal states, incorrect vtable size, and incorrect or inconsistent iftable entries) 7520 // in this class and any subclasses. 7521 DCHECK(vtable_impl == nullptr || vtable_impl == supers_method) 7522 << "vtable_impl was " << ArtMethod::PrettyMethod(vtable_impl) 7523 << " and not 'nullptr' or " 7524 << supers_method->PrettyMethod() 7525 << " as expected. IFTable appears to be corrupt!"; 7526 vtable_impl = supers_method; 7527 } 7528 } 7529 // If we haven't found it yet we should search through the interfaces for default methods. 7530 ArtMethod* current_method = helper.FindMethod(interface_method, 7531 interface_name_comparator, 7532 vtable_impl); 7533 if (LIKELY(fill_tables)) { 7534 if (current_method == nullptr && !super_interface) { 7535 // We could not find an implementation for this method and since it is a brand new 7536 // interface we searched the entire vtable (and all default methods) for an 7537 // implementation but couldn't find one. We therefore need to make a miranda method. 7538 current_method = helper.GetOrCreateMirandaMethod(interface_method, 7539 interface_name_comparator); 7540 } 7541 7542 if (current_method != nullptr) { 7543 // We found a default method implementation. Record it in the iftable and IMT. 7544 method_array->SetElementPtrSize(j, current_method, image_pointer_size_); 7545 SetIMTRef(unimplemented_method, 7546 imt_conflict_method, 7547 current_method, 7548 /*out*/out_new_conflict, 7549 /*out*/imt_ptr); 7550 } 7551 } 7552 } // For each method in interface end. 7553 } // if (num_methods > 0) 7554 } // For each interface. 7555 // TODO don't extend virtuals of interface unless necessary (when is it?). 7556 if (helper.HasNewVirtuals()) { 7557 LengthPrefixedArray<ArtMethod>* old_methods = kIsDebugBuild ? klass->GetMethodsPtr() : nullptr; 7558 helper.ReallocMethods(); // No return value to check. Native allocation failure aborts. 7559 LengthPrefixedArray<ArtMethod>* methods = kIsDebugBuild ? klass->GetMethodsPtr() : nullptr; 7560 7561 // Done copying methods, they are all roots in the class now, so we can end the no thread 7562 // suspension assert. 7563 self->EndAssertNoThreadSuspension(old_cause); 7564 7565 if (fill_tables) { 7566 vtable.Assign(helper.UpdateVtable(default_translations, vtable.Get())); 7567 if (UNLIKELY(vtable == nullptr)) { 7568 // The helper has already called self->AssertPendingOOMException(); 7569 return false; 7570 } 7571 helper.UpdateIfTable(iftable); 7572 helper.UpdateIMT(out_imt); 7573 } 7574 7575 helper.CheckNoStaleMethodsInDexCache(); 7576 helper.ClobberOldMethods(old_methods, methods); 7577 } else { 7578 self->EndAssertNoThreadSuspension(old_cause); 7579 } 7580 if (kIsDebugBuild && !is_interface) { 7581 SanityCheckVTable(self, klass, image_pointer_size_); 7582 } 7583 return true; 7584 } 7585 7586 bool ClassLinker::LinkInstanceFields(Thread* self, Handle<mirror::Class> klass) { 7587 CHECK(klass != nullptr); 7588 return LinkFields(self, klass, false, nullptr); 7589 } 7590 7591 bool ClassLinker::LinkStaticFields(Thread* self, Handle<mirror::Class> klass, size_t* class_size) { 7592 CHECK(klass != nullptr); 7593 return LinkFields(self, klass, true, class_size); 7594 } 7595 7596 struct LinkFieldsComparator { 7597 explicit LinkFieldsComparator() REQUIRES_SHARED(Locks::mutator_lock_) { 7598 } 7599 // No thread safety analysis as will be called from STL. Checked lock held in constructor. 7600 bool operator()(ArtField* field1, ArtField* field2) 7601 NO_THREAD_SAFETY_ANALYSIS { 7602 // First come reference fields, then 64-bit, then 32-bit, and then 16-bit, then finally 8-bit. 7603 Primitive::Type type1 = field1->GetTypeAsPrimitiveType(); 7604 Primitive::Type type2 = field2->GetTypeAsPrimitiveType(); 7605 if (type1 != type2) { 7606 if (type1 == Primitive::kPrimNot) { 7607 // Reference always goes first. 7608 return true; 7609 } 7610 if (type2 == Primitive::kPrimNot) { 7611 // Reference always goes first. 7612 return false; 7613 } 7614 size_t size1 = Primitive::ComponentSize(type1); 7615 size_t size2 = Primitive::ComponentSize(type2); 7616 if (size1 != size2) { 7617 // Larger primitive types go first. 7618 return size1 > size2; 7619 } 7620 // Primitive types differ but sizes match. Arbitrarily order by primitive type. 7621 return type1 < type2; 7622 } 7623 // Same basic group? Then sort by dex field index. This is guaranteed to be sorted 7624 // by name and for equal names by type id index. 7625 // NOTE: This works also for proxies. Their static fields are assigned appropriate indexes. 7626 return field1->GetDexFieldIndex() < field2->GetDexFieldIndex(); 7627 } 7628 }; 7629 7630 bool ClassLinker::LinkFields(Thread* self, 7631 Handle<mirror::Class> klass, 7632 bool is_static, 7633 size_t* class_size) { 7634 self->AllowThreadSuspension(); 7635 const size_t num_fields = is_static ? klass->NumStaticFields() : klass->NumInstanceFields(); 7636 LengthPrefixedArray<ArtField>* const fields = is_static ? klass->GetSFieldsPtr() : 7637 klass->GetIFieldsPtr(); 7638 7639 // Initialize field_offset 7640 MemberOffset field_offset(0); 7641 if (is_static) { 7642 field_offset = klass->GetFirstReferenceStaticFieldOffsetDuringLinking(image_pointer_size_); 7643 } else { 7644 ObjPtr<mirror::Class> super_class = klass->GetSuperClass(); 7645 if (super_class != nullptr) { 7646 CHECK(super_class->IsResolved()) 7647 << klass->PrettyClass() << " " << super_class->PrettyClass(); 7648 field_offset = MemberOffset(super_class->GetObjectSize()); 7649 } 7650 } 7651 7652 CHECK_EQ(num_fields == 0, fields == nullptr) << klass->PrettyClass(); 7653 7654 // we want a relatively stable order so that adding new fields 7655 // minimizes disruption of C++ version such as Class and Method. 7656 // 7657 // The overall sort order order is: 7658 // 1) All object reference fields, sorted alphabetically. 7659 // 2) All java long (64-bit) integer fields, sorted alphabetically. 7660 // 3) All java double (64-bit) floating point fields, sorted alphabetically. 7661 // 4) All java int (32-bit) integer fields, sorted alphabetically. 7662 // 5) All java float (32-bit) floating point fields, sorted alphabetically. 7663 // 6) All java char (16-bit) integer fields, sorted alphabetically. 7664 // 7) All java short (16-bit) integer fields, sorted alphabetically. 7665 // 8) All java boolean (8-bit) integer fields, sorted alphabetically. 7666 // 9) All java byte (8-bit) integer fields, sorted alphabetically. 7667 // 7668 // Once the fields are sorted in this order we will attempt to fill any gaps that might be present 7669 // in the memory layout of the structure. See ShuffleForward for how this is done. 7670 std::deque<ArtField*> grouped_and_sorted_fields; 7671 const char* old_no_suspend_cause = self->StartAssertNoThreadSuspension( 7672 "Naked ArtField references in deque"); 7673 for (size_t i = 0; i < num_fields; i++) { 7674 grouped_and_sorted_fields.push_back(&fields->At(i)); 7675 } 7676 std::sort(grouped_and_sorted_fields.begin(), grouped_and_sorted_fields.end(), 7677 LinkFieldsComparator()); 7678 7679 // References should be at the front. 7680 size_t current_field = 0; 7681 size_t num_reference_fields = 0; 7682 FieldGaps gaps; 7683 7684 for (; current_field < num_fields; current_field++) { 7685 ArtField* field = grouped_and_sorted_fields.front(); 7686 Primitive::Type type = field->GetTypeAsPrimitiveType(); 7687 bool isPrimitive = type != Primitive::kPrimNot; 7688 if (isPrimitive) { 7689 break; // past last reference, move on to the next phase 7690 } 7691 if (UNLIKELY(!IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>( 7692 field_offset.Uint32Value()))) { 7693 MemberOffset old_offset = field_offset; 7694 field_offset = MemberOffset(RoundUp(field_offset.Uint32Value(), 4)); 7695 AddFieldGap(old_offset.Uint32Value(), field_offset.Uint32Value(), &gaps); 7696 } 7697 DCHECK_ALIGNED(field_offset.Uint32Value(), sizeof(mirror::HeapReference<mirror::Object>)); 7698 grouped_and_sorted_fields.pop_front(); 7699 num_reference_fields++; 7700 field->SetOffset(field_offset); 7701 field_offset = MemberOffset(field_offset.Uint32Value() + 7702 sizeof(mirror::HeapReference<mirror::Object>)); 7703 } 7704 // Gaps are stored as a max heap which means that we must shuffle from largest to smallest 7705 // otherwise we could end up with suboptimal gap fills. 7706 ShuffleForward<8>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 7707 ShuffleForward<4>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 7708 ShuffleForward<2>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 7709 ShuffleForward<1>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps); 7710 CHECK(grouped_and_sorted_fields.empty()) << "Missed " << grouped_and_sorted_fields.size() << 7711 " fields."; 7712 self->EndAssertNoThreadSuspension(old_no_suspend_cause); 7713 7714 // We lie to the GC about the java.lang.ref.Reference.referent field, so it doesn't scan it. 7715 if (!is_static && klass->DescriptorEquals("Ljava/lang/ref/Reference;")) { 7716 // We know there are no non-reference fields in the Reference classes, and we know 7717 // that 'referent' is alphabetically last, so this is easy... 7718 CHECK_EQ(num_reference_fields, num_fields) << klass->PrettyClass(); 7719 CHECK_STREQ(fields->At(num_fields - 1).GetName(), "referent") 7720 << klass->PrettyClass(); 7721 --num_reference_fields; 7722 } 7723 7724 size_t size = field_offset.Uint32Value(); 7725 // Update klass 7726 if (is_static) { 7727 klass->SetNumReferenceStaticFields(num_reference_fields); 7728 *class_size = size; 7729 } else { 7730 klass->SetNumReferenceInstanceFields(num_reference_fields); 7731 ObjPtr<mirror::Class> super_class = klass->GetSuperClass(); 7732 if (num_reference_fields == 0 || super_class == nullptr) { 7733 // object has one reference field, klass, but we ignore it since we always visit the class. 7734 // super_class is null iff the class is java.lang.Object. 7735 if (super_class == nullptr || 7736 (super_class->GetClassFlags() & mirror::kClassFlagNoReferenceFields) != 0) { 7737 klass->SetClassFlags(klass->GetClassFlags() | mirror::kClassFlagNoReferenceFields); 7738 } 7739 } 7740 if (kIsDebugBuild) { 7741 DCHECK_EQ(super_class == nullptr, klass->DescriptorEquals("Ljava/lang/Object;")); 7742 size_t total_reference_instance_fields = 0; 7743 ObjPtr<mirror::Class> cur_super = klass.Get(); 7744 while (cur_super != nullptr) { 7745 total_reference_instance_fields += cur_super->NumReferenceInstanceFieldsDuringLinking(); 7746 cur_super = cur_super->GetSuperClass(); 7747 } 7748 if (super_class == nullptr) { 7749 CHECK_EQ(total_reference_instance_fields, 1u) << klass->PrettyDescriptor(); 7750 } else { 7751 // Check that there is at least num_reference_fields other than Object.class. 7752 CHECK_GE(total_reference_instance_fields, 1u + num_reference_fields) 7753 << klass->PrettyClass(); 7754 } 7755 } 7756 if (!klass->IsVariableSize()) { 7757 std::string temp; 7758 DCHECK_GE(size, sizeof(mirror::Object)) << klass->GetDescriptor(&temp); 7759 size_t previous_size = klass->GetObjectSize(); 7760 if (previous_size != 0) { 7761 // Make sure that we didn't originally have an incorrect size. 7762 CHECK_EQ(previous_size, size) << klass->GetDescriptor(&temp); 7763 } 7764 klass->SetObjectSize(size); 7765 } 7766 } 7767 7768 if (kIsDebugBuild) { 7769 // Make sure that the fields array is ordered by name but all reference 7770 // offsets are at the beginning as far as alignment allows. 7771 MemberOffset start_ref_offset = is_static 7772 ? klass->GetFirstReferenceStaticFieldOffsetDuringLinking(image_pointer_size_) 7773 : klass->GetFirstReferenceInstanceFieldOffset(); 7774 MemberOffset end_ref_offset(start_ref_offset.Uint32Value() + 7775 num_reference_fields * 7776 sizeof(mirror::HeapReference<mirror::Object>)); 7777 MemberOffset current_ref_offset = start_ref_offset; 7778 for (size_t i = 0; i < num_fields; i++) { 7779 ArtField* field = &fields->At(i); 7780 VLOG(class_linker) << "LinkFields: " << (is_static ? "static" : "instance") 7781 << " class=" << klass->PrettyClass() << " field=" << field->PrettyField() 7782 << " offset=" << field->GetOffsetDuringLinking(); 7783 if (i != 0) { 7784 ArtField* const prev_field = &fields->At(i - 1); 7785 // NOTE: The field names can be the same. This is not possible in the Java language 7786 // but it's valid Java/dex bytecode and for example proguard can generate such bytecode. 7787 DCHECK_LE(strcmp(prev_field->GetName(), field->GetName()), 0); 7788 } 7789 Primitive::Type type = field->GetTypeAsPrimitiveType(); 7790 bool is_primitive = type != Primitive::kPrimNot; 7791 if (klass->DescriptorEquals("Ljava/lang/ref/Reference;") && 7792 strcmp("referent", field->GetName()) == 0) { 7793 is_primitive = true; // We lied above, so we have to expect a lie here. 7794 } 7795 MemberOffset offset = field->GetOffsetDuringLinking(); 7796 if (is_primitive) { 7797 if (offset.Uint32Value() < end_ref_offset.Uint32Value()) { 7798 // Shuffled before references. 7799 size_t type_size = Primitive::ComponentSize(type); 7800 CHECK_LT(type_size, sizeof(mirror::HeapReference<mirror::Object>)); 7801 CHECK_LT(offset.Uint32Value(), start_ref_offset.Uint32Value()); 7802 CHECK_LE(offset.Uint32Value() + type_size, start_ref_offset.Uint32Value()); 7803 CHECK(!IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>(offset.Uint32Value())); 7804 } 7805 } else { 7806 CHECK_EQ(current_ref_offset.Uint32Value(), offset.Uint32Value()); 7807 current_ref_offset = MemberOffset(current_ref_offset.Uint32Value() + 7808 sizeof(mirror::HeapReference<mirror::Object>)); 7809 } 7810 } 7811 CHECK_EQ(current_ref_offset.Uint32Value(), end_ref_offset.Uint32Value()); 7812 } 7813 return true; 7814 } 7815 7816 // Set the bitmap of reference instance field offsets. 7817 void ClassLinker::CreateReferenceInstanceOffsets(Handle<mirror::Class> klass) { 7818 uint32_t reference_offsets = 0; 7819 ObjPtr<mirror::Class> super_class = klass->GetSuperClass(); 7820 // Leave the reference offsets as 0 for mirror::Object (the class field is handled specially). 7821 if (super_class != nullptr) { 7822 reference_offsets = super_class->GetReferenceInstanceOffsets(); 7823 // Compute reference offsets unless our superclass overflowed. 7824 if (reference_offsets != mirror::Class::kClassWalkSuper) { 7825 size_t num_reference_fields = klass->NumReferenceInstanceFieldsDuringLinking(); 7826 if (num_reference_fields != 0u) { 7827 // All of the fields that contain object references are guaranteed be grouped in memory 7828 // starting at an appropriately aligned address after super class object data. 7829 uint32_t start_offset = RoundUp(super_class->GetObjectSize(), 7830 sizeof(mirror::HeapReference<mirror::Object>)); 7831 uint32_t start_bit = (start_offset - mirror::kObjectHeaderSize) / 7832 sizeof(mirror::HeapReference<mirror::Object>); 7833 if (start_bit + num_reference_fields > 32) { 7834 reference_offsets = mirror::Class::kClassWalkSuper; 7835 } else { 7836 reference_offsets |= (0xffffffffu << start_bit) & 7837 (0xffffffffu >> (32 - (start_bit + num_reference_fields))); 7838 } 7839 } 7840 } 7841 } 7842 klass->SetReferenceInstanceOffsets(reference_offsets); 7843 } 7844 7845 mirror::String* ClassLinker::ResolveString(const DexFile& dex_file, 7846 dex::StringIndex string_idx, 7847 Handle<mirror::DexCache> dex_cache) { 7848 DCHECK(dex_cache != nullptr); 7849 Thread::PoisonObjectPointersIfDebug(); 7850 ObjPtr<mirror::String> resolved = dex_cache->GetResolvedString(string_idx); 7851 if (resolved != nullptr) { 7852 return resolved.Ptr(); 7853 } 7854 uint32_t utf16_length; 7855 const char* utf8_data = dex_file.StringDataAndUtf16LengthByIdx(string_idx, &utf16_length); 7856 ObjPtr<mirror::String> string = intern_table_->InternStrong(utf16_length, utf8_data); 7857 if (string != nullptr) { 7858 dex_cache->SetResolvedString(string_idx, string); 7859 } 7860 return string.Ptr(); 7861 } 7862 7863 mirror::String* ClassLinker::LookupString(const DexFile& dex_file, 7864 dex::StringIndex string_idx, 7865 ObjPtr<mirror::DexCache> dex_cache) { 7866 DCHECK(dex_cache != nullptr); 7867 ObjPtr<mirror::String> resolved = dex_cache->GetResolvedString(string_idx); 7868 if (resolved != nullptr) { 7869 return resolved.Ptr(); 7870 } 7871 uint32_t utf16_length; 7872 const char* utf8_data = dex_file.StringDataAndUtf16LengthByIdx(string_idx, &utf16_length); 7873 ObjPtr<mirror::String> string = 7874 intern_table_->LookupStrong(Thread::Current(), utf16_length, utf8_data); 7875 if (string != nullptr) { 7876 dex_cache->SetResolvedString(string_idx, string); 7877 } 7878 return string.Ptr(); 7879 } 7880 7881 ObjPtr<mirror::Class> ClassLinker::LookupResolvedType(const DexFile& dex_file, 7882 dex::TypeIndex type_idx, 7883 ObjPtr<mirror::DexCache> dex_cache, 7884 ObjPtr<mirror::ClassLoader> class_loader) { 7885 ObjPtr<mirror::Class> type = dex_cache->GetResolvedType(type_idx); 7886 if (type == nullptr) { 7887 const char* descriptor = dex_file.StringByTypeIdx(type_idx); 7888 DCHECK_NE(*descriptor, '\0') << "descriptor is empty string"; 7889 if (descriptor[1] == '\0') { 7890 // only the descriptors of primitive types should be 1 character long, also avoid class lookup 7891 // for primitive classes that aren't backed by dex files. 7892 type = FindPrimitiveClass(descriptor[0]); 7893 } else { 7894 Thread* const self = Thread::Current(); 7895 DCHECK(self != nullptr); 7896 const size_t hash = ComputeModifiedUtf8Hash(descriptor); 7897 // Find the class in the loaded classes table. 7898 type = LookupClass(self, descriptor, hash, class_loader.Ptr()); 7899 } 7900 if (type != nullptr) { 7901 if (type->IsResolved()) { 7902 dex_cache->SetResolvedType(type_idx, type); 7903 } else { 7904 type = nullptr; 7905 } 7906 } 7907 } 7908 DCHECK(type == nullptr || type->IsResolved()); 7909 return type; 7910 } 7911 7912 mirror::Class* ClassLinker::ResolveType(const DexFile& dex_file, 7913 dex::TypeIndex type_idx, 7914 ObjPtr<mirror::Class> referrer) { 7915 StackHandleScope<2> hs(Thread::Current()); 7916 Handle<mirror::DexCache> dex_cache(hs.NewHandle(referrer->GetDexCache())); 7917 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(referrer->GetClassLoader())); 7918 return ResolveType(dex_file, type_idx, dex_cache, class_loader); 7919 } 7920 7921 mirror::Class* ClassLinker::ResolveType(const DexFile& dex_file, 7922 dex::TypeIndex type_idx, 7923 Handle<mirror::DexCache> dex_cache, 7924 Handle<mirror::ClassLoader> class_loader) { 7925 DCHECK(dex_cache != nullptr); 7926 Thread::PoisonObjectPointersIfDebug(); 7927 ObjPtr<mirror::Class> resolved = dex_cache->GetResolvedType(type_idx); 7928 if (resolved == nullptr) { 7929 // TODO: Avoid this lookup as it duplicates work done in FindClass(). It is here 7930 // as a workaround for FastNative JNI to avoid AssertNoPendingException() when 7931 // trying to resolve annotations while an exception may be pending. Bug: 34659969 7932 resolved = LookupResolvedType(dex_file, type_idx, dex_cache.Get(), class_loader.Get()); 7933 } 7934 if (resolved == nullptr) { 7935 Thread* self = Thread::Current(); 7936 const char* descriptor = dex_file.StringByTypeIdx(type_idx); 7937 resolved = FindClass(self, descriptor, class_loader); 7938 if (resolved != nullptr) { 7939 // TODO: we used to throw here if resolved's class loader was not the 7940 // boot class loader. This was to permit different classes with the 7941 // same name to be loaded simultaneously by different loaders 7942 dex_cache->SetResolvedType(type_idx, resolved); 7943 } else { 7944 CHECK(self->IsExceptionPending()) 7945 << "Expected pending exception for failed resolution of: " << descriptor; 7946 // Convert a ClassNotFoundException to a NoClassDefFoundError. 7947 StackHandleScope<1> hs(self); 7948 Handle<mirror::Throwable> cause(hs.NewHandle(self->GetException())); 7949 if (cause->InstanceOf(GetClassRoot(kJavaLangClassNotFoundException))) { 7950 DCHECK(resolved == nullptr); // No Handle needed to preserve resolved. 7951 self->ClearException(); 7952 ThrowNoClassDefFoundError("Failed resolution of: %s", descriptor); 7953 self->GetException()->SetCause(cause.Get()); 7954 } 7955 } 7956 } 7957 DCHECK((resolved == nullptr) || resolved->IsResolved()) 7958 << resolved->PrettyDescriptor() << " " << resolved->GetStatus(); 7959 return resolved.Ptr(); 7960 } 7961 7962 template <ClassLinker::ResolveMode kResolveMode> 7963 ArtMethod* ClassLinker::ResolveMethod(const DexFile& dex_file, 7964 uint32_t method_idx, 7965 Handle<mirror::DexCache> dex_cache, 7966 Handle<mirror::ClassLoader> class_loader, 7967 ArtMethod* referrer, 7968 InvokeType type) { 7969 DCHECK(dex_cache != nullptr); 7970 DCHECK(referrer == nullptr || !referrer->IsProxyMethod()); 7971 // Check for hit in the dex cache. 7972 PointerSize pointer_size = image_pointer_size_; 7973 ArtMethod* resolved = dex_cache->GetResolvedMethod(method_idx, pointer_size); 7974 Thread::PoisonObjectPointersIfDebug(); 7975 DCHECK(resolved == nullptr || !resolved->IsRuntimeMethod()); 7976 bool valid_dex_cache_method = resolved != nullptr; 7977 if (kResolveMode == ResolveMode::kNoChecks && valid_dex_cache_method) { 7978 // We have a valid method from the DexCache and no checks to perform. 7979 DCHECK(resolved->GetDeclaringClassUnchecked() != nullptr) << resolved->GetDexMethodIndex(); 7980 return resolved; 7981 } 7982 const DexFile::MethodId& method_id = dex_file.GetMethodId(method_idx); 7983 ObjPtr<mirror::Class> klass = nullptr; 7984 if (valid_dex_cache_method) { 7985 // We have a valid method from the DexCache but we need to perform ICCE and IAE checks. 7986 DCHECK(resolved->GetDeclaringClassUnchecked() != nullptr) << resolved->GetDexMethodIndex(); 7987 klass = LookupResolvedType(dex_file, method_id.class_idx_, dex_cache.Get(), class_loader.Get()); 7988 CHECK(klass != nullptr) << resolved->PrettyMethod() << " " << resolved << " " 7989 << resolved->GetAccessFlags(); 7990 } else { 7991 // The method was not in the DexCache, resolve the declaring class. 7992 klass = ResolveType(dex_file, method_id.class_idx_, dex_cache, class_loader); 7993 if (klass == nullptr) { 7994 DCHECK(Thread::Current()->IsExceptionPending()); 7995 return nullptr; 7996 } 7997 } 7998 7999 // Check if the invoke type matches the class type. 8000 if (kResolveMode == ResolveMode::kCheckICCEAndIAE && 8001 CheckInvokeClassMismatch</* kThrow */ true>( 8002 dex_cache.Get(), type, [klass]() { return klass; })) { 8003 DCHECK(Thread::Current()->IsExceptionPending()); 8004 return nullptr; 8005 } 8006 8007 if (!valid_dex_cache_method) { 8008 // Search for the method using dex_cache and method_idx. The Class::Find*Method() 8009 // functions can optimize the search if the dex_cache is the same as the DexCache 8010 // of the class, with fall-back to name and signature search otherwise. 8011 if (klass->IsInterface()) { 8012 resolved = klass->FindInterfaceMethod(dex_cache.Get(), method_idx, pointer_size); 8013 } else { 8014 resolved = klass->FindClassMethod(dex_cache.Get(), method_idx, pointer_size); 8015 } 8016 DCHECK(resolved == nullptr || resolved->GetDeclaringClassUnchecked() != nullptr); 8017 if (resolved != nullptr) { 8018 // Be a good citizen and update the dex cache to speed subsequent calls. 8019 dex_cache->SetResolvedMethod(method_idx, resolved, pointer_size); 8020 } 8021 } 8022 8023 // Note: We can check for IllegalAccessError only if we have a referrer. 8024 if (kResolveMode == ResolveMode::kCheckICCEAndIAE && resolved != nullptr && referrer != nullptr) { 8025 ObjPtr<mirror::Class> methods_class = resolved->GetDeclaringClass(); 8026 ObjPtr<mirror::Class> referring_class = referrer->GetDeclaringClass(); 8027 if (!referring_class->CheckResolvedMethodAccess(methods_class, 8028 resolved, 8029 dex_cache.Get(), 8030 method_idx, 8031 type)) { 8032 DCHECK(Thread::Current()->IsExceptionPending()); 8033 return nullptr; 8034 } 8035 } 8036 8037 // If we found a method, check for incompatible class changes. 8038 if (LIKELY(resolved != nullptr) && 8039 LIKELY(kResolveMode == ResolveMode::kNoChecks || 8040 !resolved->CheckIncompatibleClassChange(type))) { 8041 return resolved; 8042 } else { 8043 // If we had a method, or if we can find one with another lookup type, 8044 // it's an incompatible-class-change error. 8045 if (resolved == nullptr) { 8046 if (klass->IsInterface()) { 8047 resolved = klass->FindClassMethod(dex_cache.Get(), method_idx, pointer_size); 8048 } else { 8049 // If there was an interface method with the same signature, 8050 // we would have found it also in the "copied" methods. 8051 DCHECK(klass->FindInterfaceMethod(dex_cache.Get(), method_idx, pointer_size) == nullptr); 8052 } 8053 } 8054 if (resolved != nullptr) { 8055 ThrowIncompatibleClassChangeError(type, resolved->GetInvokeType(), resolved, referrer); 8056 } else { 8057 // We failed to find the method (using all lookup types), so throw a NoSuchMethodError. 8058 const char* name = dex_file.StringDataByIdx(method_id.name_idx_); 8059 const Signature signature = dex_file.GetMethodSignature(method_id); 8060 ThrowNoSuchMethodError(type, klass, name, signature); 8061 } 8062 Thread::Current()->AssertPendingException(); 8063 return nullptr; 8064 } 8065 } 8066 8067 ArtMethod* ClassLinker::ResolveMethodWithoutInvokeType(const DexFile& dex_file, 8068 uint32_t method_idx, 8069 Handle<mirror::DexCache> dex_cache, 8070 Handle<mirror::ClassLoader> class_loader) { 8071 ArtMethod* resolved = dex_cache->GetResolvedMethod(method_idx, image_pointer_size_); 8072 Thread::PoisonObjectPointersIfDebug(); 8073 if (resolved != nullptr) { 8074 DCHECK(!resolved->IsRuntimeMethod()); 8075 DCHECK(resolved->GetDeclaringClassUnchecked() != nullptr) << resolved->GetDexMethodIndex(); 8076 return resolved; 8077 } 8078 // Fail, get the declaring class. 8079 const DexFile::MethodId& method_id = dex_file.GetMethodId(method_idx); 8080 ObjPtr<mirror::Class> klass = 8081 ResolveType(dex_file, method_id.class_idx_, dex_cache, class_loader); 8082 if (klass == nullptr) { 8083 Thread::Current()->AssertPendingException(); 8084 return nullptr; 8085 } 8086 if (klass->IsInterface()) { 8087 resolved = klass->FindInterfaceMethod(dex_cache.Get(), method_idx, image_pointer_size_); 8088 } else { 8089 resolved = klass->FindClassMethod(dex_cache.Get(), method_idx, image_pointer_size_); 8090 } 8091 8092 return resolved; 8093 } 8094 8095 ArtField* ClassLinker::LookupResolvedField(uint32_t field_idx, 8096 ObjPtr<mirror::DexCache> dex_cache, 8097 ObjPtr<mirror::ClassLoader> class_loader, 8098 bool is_static) { 8099 const DexFile& dex_file = *dex_cache->GetDexFile(); 8100 const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx); 8101 ObjPtr<mirror::Class> klass = dex_cache->GetResolvedType(field_id.class_idx_); 8102 if (klass == nullptr) { 8103 klass = LookupResolvedType(dex_file, field_id.class_idx_, dex_cache, class_loader); 8104 } 8105 if (klass == nullptr) { 8106 // The class has not been resolved yet, so the field is also unresolved. 8107 return nullptr; 8108 } 8109 DCHECK(klass->IsResolved()); 8110 Thread* self = is_static ? Thread::Current() : nullptr; 8111 8112 // First try to find a field declared directly by `klass` by the field index. 8113 ArtField* resolved_field = is_static 8114 ? mirror::Class::FindStaticField(self, klass, dex_cache, field_idx) 8115 : klass->FindInstanceField(dex_cache, field_idx); 8116 8117 if (resolved_field == nullptr) { 8118 // If not found in `klass` by field index, search the class hierarchy using the name and type. 8119 const char* name = dex_file.GetFieldName(field_id); 8120 const char* type = dex_file.GetFieldTypeDescriptor(field_id); 8121 resolved_field = is_static 8122 ? mirror::Class::FindStaticField(self, klass, name, type) 8123 : klass->FindInstanceField(name, type); 8124 } 8125 8126 if (resolved_field != nullptr) { 8127 dex_cache->SetResolvedField(field_idx, resolved_field, image_pointer_size_); 8128 } 8129 return resolved_field; 8130 } 8131 8132 ArtField* ClassLinker::ResolveField(const DexFile& dex_file, 8133 uint32_t field_idx, 8134 Handle<mirror::DexCache> dex_cache, 8135 Handle<mirror::ClassLoader> class_loader, 8136 bool is_static) { 8137 DCHECK(dex_cache != nullptr); 8138 ArtField* resolved = dex_cache->GetResolvedField(field_idx, image_pointer_size_); 8139 Thread::PoisonObjectPointersIfDebug(); 8140 if (resolved != nullptr) { 8141 return resolved; 8142 } 8143 const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx); 8144 Thread* const self = Thread::Current(); 8145 ObjPtr<mirror::Class> klass = ResolveType(dex_file, field_id.class_idx_, dex_cache, class_loader); 8146 if (klass == nullptr) { 8147 DCHECK(Thread::Current()->IsExceptionPending()); 8148 return nullptr; 8149 } 8150 8151 if (is_static) { 8152 resolved = mirror::Class::FindStaticField(self, klass, dex_cache.Get(), field_idx); 8153 } else { 8154 resolved = klass->FindInstanceField(dex_cache.Get(), field_idx); 8155 } 8156 8157 if (resolved == nullptr) { 8158 const char* name = dex_file.GetFieldName(field_id); 8159 const char* type = dex_file.GetFieldTypeDescriptor(field_id); 8160 if (is_static) { 8161 resolved = mirror::Class::FindStaticField(self, klass, name, type); 8162 } else { 8163 resolved = klass->FindInstanceField(name, type); 8164 } 8165 if (resolved == nullptr) { 8166 ThrowNoSuchFieldError(is_static ? "static " : "instance ", klass, type, name); 8167 return nullptr; 8168 } 8169 } 8170 dex_cache->SetResolvedField(field_idx, resolved, image_pointer_size_); 8171 return resolved; 8172 } 8173 8174 ArtField* ClassLinker::ResolveFieldJLS(const DexFile& dex_file, 8175 uint32_t field_idx, 8176 Handle<mirror::DexCache> dex_cache, 8177 Handle<mirror::ClassLoader> class_loader) { 8178 DCHECK(dex_cache != nullptr); 8179 ArtField* resolved = dex_cache->GetResolvedField(field_idx, image_pointer_size_); 8180 Thread::PoisonObjectPointersIfDebug(); 8181 if (resolved != nullptr) { 8182 return resolved; 8183 } 8184 const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx); 8185 Thread* self = Thread::Current(); 8186 ObjPtr<mirror::Class> klass(ResolveType(dex_file, field_id.class_idx_, dex_cache, class_loader)); 8187 if (klass == nullptr) { 8188 DCHECK(Thread::Current()->IsExceptionPending()); 8189 return nullptr; 8190 } 8191 8192 StringPiece name(dex_file.GetFieldName(field_id)); 8193 StringPiece type(dex_file.GetFieldTypeDescriptor(field_id)); 8194 resolved = mirror::Class::FindField(self, klass, name, type); 8195 if (resolved != nullptr) { 8196 dex_cache->SetResolvedField(field_idx, resolved, image_pointer_size_); 8197 } else { 8198 ThrowNoSuchFieldError("", klass, type, name); 8199 } 8200 return resolved; 8201 } 8202 8203 mirror::MethodType* ClassLinker::ResolveMethodType(const DexFile& dex_file, 8204 uint32_t proto_idx, 8205 Handle<mirror::DexCache> dex_cache, 8206 Handle<mirror::ClassLoader> class_loader) { 8207 DCHECK(Runtime::Current()->IsMethodHandlesEnabled()); 8208 DCHECK(dex_cache != nullptr); 8209 8210 ObjPtr<mirror::MethodType> resolved = dex_cache->GetResolvedMethodType(proto_idx); 8211 if (resolved != nullptr) { 8212 return resolved.Ptr(); 8213 } 8214 8215 Thread* const self = Thread::Current(); 8216 StackHandleScope<4> hs(self); 8217 8218 // First resolve the return type. 8219 const DexFile::ProtoId& proto_id = dex_file.GetProtoId(proto_idx); 8220 Handle<mirror::Class> return_type(hs.NewHandle( 8221 ResolveType(dex_file, proto_id.return_type_idx_, dex_cache, class_loader))); 8222 if (return_type == nullptr) { 8223 DCHECK(self->IsExceptionPending()); 8224 return nullptr; 8225 } 8226 8227 // Then resolve the argument types. 8228 // 8229 // TODO: Is there a better way to figure out the number of method arguments 8230 // other than by looking at the shorty ? 8231 const size_t num_method_args = strlen(dex_file.StringDataByIdx(proto_id.shorty_idx_)) - 1; 8232 8233 ObjPtr<mirror::Class> class_type = mirror::Class::GetJavaLangClass(); 8234 ObjPtr<mirror::Class> array_of_class = FindArrayClass(self, &class_type); 8235 Handle<mirror::ObjectArray<mirror::Class>> method_params(hs.NewHandle( 8236 mirror::ObjectArray<mirror::Class>::Alloc(self, array_of_class, num_method_args))); 8237 if (method_params == nullptr) { 8238 DCHECK(self->IsExceptionPending()); 8239 return nullptr; 8240 } 8241 8242 DexFileParameterIterator it(dex_file, proto_id); 8243 int32_t i = 0; 8244 MutableHandle<mirror::Class> param_class = hs.NewHandle<mirror::Class>(nullptr); 8245 for (; it.HasNext(); it.Next()) { 8246 const dex::TypeIndex type_idx = it.GetTypeIdx(); 8247 param_class.Assign(ResolveType(dex_file, type_idx, dex_cache, class_loader)); 8248 if (param_class == nullptr) { 8249 DCHECK(self->IsExceptionPending()); 8250 return nullptr; 8251 } 8252 8253 method_params->Set(i++, param_class.Get()); 8254 } 8255 8256 DCHECK(!it.HasNext()); 8257 8258 Handle<mirror::MethodType> type = hs.NewHandle( 8259 mirror::MethodType::Create(self, return_type, method_params)); 8260 dex_cache->SetResolvedMethodType(proto_idx, type.Get()); 8261 8262 return type.Get(); 8263 } 8264 8265 mirror::MethodHandle* ClassLinker::ResolveMethodHandleForField( 8266 Thread* self, 8267 const DexFile::MethodHandleItem& method_handle, 8268 ArtMethod* referrer) { 8269 DexFile::MethodHandleType handle_type = 8270 static_cast<DexFile::MethodHandleType>(method_handle.method_handle_type_); 8271 mirror::MethodHandle::Kind kind; 8272 bool is_static; 8273 int32_t num_params; 8274 switch (handle_type) { 8275 case DexFile::MethodHandleType::kStaticPut: { 8276 kind = mirror::MethodHandle::Kind::kStaticPut; 8277 is_static = true; 8278 num_params = 1; 8279 break; 8280 } 8281 case DexFile::MethodHandleType::kStaticGet: { 8282 kind = mirror::MethodHandle::Kind::kStaticGet; 8283 is_static = true; 8284 num_params = 0; 8285 break; 8286 } 8287 case DexFile::MethodHandleType::kInstancePut: { 8288 kind = mirror::MethodHandle::Kind::kInstancePut; 8289 is_static = false; 8290 num_params = 2; 8291 break; 8292 } 8293 case DexFile::MethodHandleType::kInstanceGet: { 8294 kind = mirror::MethodHandle::Kind::kInstanceGet; 8295 is_static = false; 8296 num_params = 1; 8297 break; 8298 } 8299 case DexFile::MethodHandleType::kInvokeStatic: 8300 case DexFile::MethodHandleType::kInvokeInstance: 8301 case DexFile::MethodHandleType::kInvokeConstructor: 8302 case DexFile::MethodHandleType::kInvokeDirect: 8303 case DexFile::MethodHandleType::kInvokeInterface: 8304 UNREACHABLE(); 8305 } 8306 8307 ArtField* target_field = 8308 ResolveField(method_handle.field_or_method_idx_, referrer, is_static); 8309 if (LIKELY(target_field != nullptr)) { 8310 ObjPtr<mirror::Class> target_class = target_field->GetDeclaringClass(); 8311 ObjPtr<mirror::Class> referring_class = referrer->GetDeclaringClass(); 8312 if (UNLIKELY(!referring_class->CanAccessMember(target_class, target_field->GetAccessFlags()))) { 8313 ThrowIllegalAccessErrorField(referring_class, target_field); 8314 return nullptr; 8315 } 8316 } else { 8317 DCHECK(Thread::Current()->IsExceptionPending()); 8318 return nullptr; 8319 } 8320 8321 StackHandleScope<4> hs(self); 8322 ObjPtr<mirror::Class> class_type = mirror::Class::GetJavaLangClass(); 8323 ObjPtr<mirror::Class> array_of_class = FindArrayClass(self, &class_type); 8324 Handle<mirror::ObjectArray<mirror::Class>> method_params(hs.NewHandle( 8325 mirror::ObjectArray<mirror::Class>::Alloc(self, array_of_class, num_params))); 8326 if (UNLIKELY(method_params.Get() == nullptr)) { 8327 DCHECK(self->IsExceptionPending()); 8328 return nullptr; 8329 } 8330 8331 Handle<mirror::Class> constructor_class; 8332 Handle<mirror::Class> return_type; 8333 switch (handle_type) { 8334 case DexFile::MethodHandleType::kStaticPut: { 8335 method_params->Set(0, target_field->GetType<true>()); 8336 return_type = hs.NewHandle(FindPrimitiveClass('V')); 8337 break; 8338 } 8339 case DexFile::MethodHandleType::kStaticGet: { 8340 return_type = hs.NewHandle(target_field->GetType<true>()); 8341 break; 8342 } 8343 case DexFile::MethodHandleType::kInstancePut: { 8344 method_params->Set(0, target_field->GetDeclaringClass()); 8345 method_params->Set(1, target_field->GetType<true>()); 8346 return_type = hs.NewHandle(FindPrimitiveClass('V')); 8347 break; 8348 } 8349 case DexFile::MethodHandleType::kInstanceGet: { 8350 method_params->Set(0, target_field->GetDeclaringClass()); 8351 return_type = hs.NewHandle(target_field->GetType<true>()); 8352 break; 8353 } 8354 case DexFile::MethodHandleType::kInvokeStatic: 8355 case DexFile::MethodHandleType::kInvokeInstance: 8356 case DexFile::MethodHandleType::kInvokeConstructor: 8357 case DexFile::MethodHandleType::kInvokeDirect: 8358 case DexFile::MethodHandleType::kInvokeInterface: 8359 UNREACHABLE(); 8360 } 8361 8362 for (int32_t i = 0; i < num_params; ++i) { 8363 if (UNLIKELY(method_params->Get(i) == nullptr)) { 8364 DCHECK(self->IsExceptionPending()); 8365 return nullptr; 8366 } 8367 } 8368 8369 if (UNLIKELY(return_type.IsNull())) { 8370 DCHECK(self->IsExceptionPending()); 8371 return nullptr; 8372 } 8373 8374 Handle<mirror::MethodType> 8375 method_type(hs.NewHandle(mirror::MethodType::Create(self, return_type, method_params))); 8376 if (UNLIKELY(method_type.IsNull())) { 8377 DCHECK(self->IsExceptionPending()); 8378 return nullptr; 8379 } 8380 8381 uintptr_t target = reinterpret_cast<uintptr_t>(target_field); 8382 return mirror::MethodHandleImpl::Create(self, target, kind, method_type); 8383 } 8384 8385 mirror::MethodHandle* ClassLinker::ResolveMethodHandleForMethod( 8386 Thread* self, 8387 const DexFile* const dex_file, 8388 const DexFile::MethodHandleItem& method_handle, 8389 ArtMethod* referrer) { 8390 DexFile::MethodHandleType handle_type = 8391 static_cast<DexFile::MethodHandleType>(method_handle.method_handle_type_); 8392 mirror::MethodHandle::Kind kind; 8393 uint32_t receiver_count = 0; 8394 ArtMethod* target_method = nullptr; 8395 switch (handle_type) { 8396 case DexFile::MethodHandleType::kStaticPut: 8397 case DexFile::MethodHandleType::kStaticGet: 8398 case DexFile::MethodHandleType::kInstancePut: 8399 case DexFile::MethodHandleType::kInstanceGet: 8400 UNREACHABLE(); 8401 case DexFile::MethodHandleType::kInvokeStatic: { 8402 kind = mirror::MethodHandle::Kind::kInvokeStatic; 8403 receiver_count = 0; 8404 target_method = ResolveMethod<ResolveMode::kNoChecks>(self, 8405 method_handle.field_or_method_idx_, 8406 referrer, 8407 InvokeType::kStatic); 8408 break; 8409 } 8410 case DexFile::MethodHandleType::kInvokeInstance: { 8411 kind = mirror::MethodHandle::Kind::kInvokeVirtual; 8412 receiver_count = 1; 8413 target_method = ResolveMethod<ResolveMode::kNoChecks>(self, 8414 method_handle.field_or_method_idx_, 8415 referrer, 8416 InvokeType::kVirtual); 8417 break; 8418 } 8419 case DexFile::MethodHandleType::kInvokeConstructor: { 8420 // Constructors are currently implemented as a transform. They 8421 // are special cased later in this method. 8422 kind = mirror::MethodHandle::Kind::kInvokeTransform; 8423 receiver_count = 0; 8424 target_method = ResolveMethod<ResolveMode::kNoChecks>(self, 8425 method_handle.field_or_method_idx_, 8426 referrer, 8427 InvokeType::kDirect); 8428 break; 8429 } 8430 case DexFile::MethodHandleType::kInvokeDirect: { 8431 kind = mirror::MethodHandle::Kind::kInvokeDirect; 8432 receiver_count = 1; 8433 StackHandleScope<2> hs(self); 8434 // A constant method handle with type kInvokeDirect can refer to 8435 // a method that is private or to a method in a super class. To 8436 // disambiguate the two options, we resolve the method ignoring 8437 // the invocation type to determine if the method is private. We 8438 // then resolve again specifying the intended invocation type to 8439 // force the appropriate checks. 8440 target_method = ResolveMethodWithoutInvokeType(*dex_file, 8441 method_handle.field_or_method_idx_, 8442 hs.NewHandle(referrer->GetDexCache()), 8443 hs.NewHandle(referrer->GetClassLoader())); 8444 if (UNLIKELY(target_method == nullptr)) { 8445 break; 8446 } 8447 8448 if (target_method->IsPrivate()) { 8449 kind = mirror::MethodHandle::Kind::kInvokeDirect; 8450 target_method = ResolveMethod<ResolveMode::kNoChecks>(self, 8451 method_handle.field_or_method_idx_, 8452 referrer, 8453 InvokeType::kDirect); 8454 } else { 8455 kind = mirror::MethodHandle::Kind::kInvokeSuper; 8456 target_method = ResolveMethod<ResolveMode::kNoChecks>(self, 8457 method_handle.field_or_method_idx_, 8458 referrer, 8459 InvokeType::kSuper); 8460 if (UNLIKELY(target_method == nullptr)) { 8461 break; 8462 } 8463 // Find the method specified in the parent in referring class 8464 // so invoke-super invokes the method in the parent of the 8465 // referrer. 8466 target_method = 8467 referrer->GetDeclaringClass()->FindVirtualMethodForVirtual(target_method, 8468 kRuntimePointerSize); 8469 } 8470 break; 8471 } 8472 case DexFile::MethodHandleType::kInvokeInterface: { 8473 kind = mirror::MethodHandle::Kind::kInvokeInterface; 8474 receiver_count = 1; 8475 target_method = ResolveMethod<ResolveMode::kNoChecks>(self, 8476 method_handle.field_or_method_idx_, 8477 referrer, 8478 InvokeType::kInterface); 8479 break; 8480 } 8481 } 8482 8483 if (UNLIKELY(target_method == nullptr)) { 8484 DCHECK(Thread::Current()->IsExceptionPending()); 8485 return nullptr; 8486 } 8487 8488 ObjPtr<mirror::Class> target_class = target_method->GetDeclaringClass(); 8489 ObjPtr<mirror::Class> referring_class = referrer->GetDeclaringClass(); 8490 uint32_t access_flags = target_method->GetAccessFlags(); 8491 if (UNLIKELY(!referring_class->CanAccessMember(target_class, access_flags))) { 8492 ThrowIllegalAccessErrorMethod(referring_class, target_method); 8493 return nullptr; 8494 } 8495 8496 // Calculate the number of parameters from the method shorty. We add the 8497 // receiver count (0 or 1) and deduct one for the return value. 8498 uint32_t shorty_length; 8499 target_method->GetShorty(&shorty_length); 8500 int32_t num_params = static_cast<int32_t>(shorty_length + receiver_count - 1); 8501 8502 StackHandleScope<7> hs(self); 8503 ObjPtr<mirror::Class> class_type = mirror::Class::GetJavaLangClass(); 8504 ObjPtr<mirror::Class> array_of_class = FindArrayClass(self, &class_type); 8505 Handle<mirror::ObjectArray<mirror::Class>> method_params(hs.NewHandle( 8506 mirror::ObjectArray<mirror::Class>::Alloc(self, array_of_class, num_params))); 8507 if (method_params.Get() == nullptr) { 8508 DCHECK(self->IsExceptionPending()); 8509 return nullptr; 8510 } 8511 8512 Handle<mirror::DexCache> dex_cache(hs.NewHandle(referrer->GetDexCache())); 8513 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(referrer->GetClassLoader())); 8514 int32_t index = 0; 8515 8516 if (receiver_count != 0) { 8517 // Insert receiver 8518 method_params->Set(index++, target_method->GetDeclaringClass()); 8519 } 8520 8521 DexFileParameterIterator it(*dex_file, target_method->GetPrototype()); 8522 while (it.HasNext()) { 8523 const dex::TypeIndex type_idx = it.GetTypeIdx(); 8524 mirror::Class* klass = ResolveType(*dex_file, type_idx, dex_cache, class_loader); 8525 if (nullptr == klass) { 8526 DCHECK(self->IsExceptionPending()); 8527 return nullptr; 8528 } 8529 method_params->Set(index++, klass); 8530 it.Next(); 8531 } 8532 8533 Handle<mirror::Class> return_type = hs.NewHandle(target_method->GetReturnType(true)); 8534 if (UNLIKELY(return_type.IsNull())) { 8535 DCHECK(self->IsExceptionPending()); 8536 return nullptr; 8537 } 8538 8539 Handle<mirror::MethodType> 8540 method_type(hs.NewHandle(mirror::MethodType::Create(self, return_type, method_params))); 8541 if (UNLIKELY(method_type.IsNull())) { 8542 DCHECK(self->IsExceptionPending()); 8543 return nullptr; 8544 } 8545 8546 if (UNLIKELY(handle_type == DexFile::MethodHandleType::kInvokeConstructor)) { 8547 Handle<mirror::Class> constructor_class = hs.NewHandle(target_method->GetDeclaringClass()); 8548 Handle<mirror::MethodHandlesLookup> lookup = 8549 hs.NewHandle(mirror::MethodHandlesLookup::GetDefault(self)); 8550 return lookup->FindConstructor(self, constructor_class, method_type); 8551 } 8552 8553 uintptr_t target = reinterpret_cast<uintptr_t>(target_method); 8554 return mirror::MethodHandleImpl::Create(self, target, kind, method_type); 8555 } 8556 8557 mirror::MethodHandle* ClassLinker::ResolveMethodHandle(uint32_t method_handle_idx, 8558 ArtMethod* referrer) 8559 REQUIRES_SHARED(Locks::mutator_lock_) { 8560 Thread* const self = Thread::Current(); 8561 const DexFile* const dex_file = referrer->GetDexFile(); 8562 const DexFile::MethodHandleItem& method_handle = dex_file->GetMethodHandle(method_handle_idx); 8563 switch (static_cast<DexFile::MethodHandleType>(method_handle.method_handle_type_)) { 8564 case DexFile::MethodHandleType::kStaticPut: 8565 case DexFile::MethodHandleType::kStaticGet: 8566 case DexFile::MethodHandleType::kInstancePut: 8567 case DexFile::MethodHandleType::kInstanceGet: 8568 return ResolveMethodHandleForField(self, method_handle, referrer); 8569 case DexFile::MethodHandleType::kInvokeStatic: 8570 case DexFile::MethodHandleType::kInvokeInstance: 8571 case DexFile::MethodHandleType::kInvokeConstructor: 8572 case DexFile::MethodHandleType::kInvokeDirect: 8573 case DexFile::MethodHandleType::kInvokeInterface: 8574 return ResolveMethodHandleForMethod(self, dex_file, method_handle, referrer); 8575 } 8576 } 8577 8578 bool ClassLinker::IsQuickResolutionStub(const void* entry_point) const { 8579 return (entry_point == GetQuickResolutionStub()) || 8580 (quick_resolution_trampoline_ == entry_point); 8581 } 8582 8583 bool ClassLinker::IsQuickToInterpreterBridge(const void* entry_point) const { 8584 return (entry_point == GetQuickToInterpreterBridge()) || 8585 (quick_to_interpreter_bridge_trampoline_ == entry_point); 8586 } 8587 8588 bool ClassLinker::IsQuickGenericJniStub(const void* entry_point) const { 8589 return (entry_point == GetQuickGenericJniStub()) || 8590 (quick_generic_jni_trampoline_ == entry_point); 8591 } 8592 8593 bool ClassLinker::IsJniDlsymLookupStub(const void* entry_point) const { 8594 return entry_point == GetJniDlsymLookupStub(); 8595 } 8596 8597 const void* ClassLinker::GetRuntimeQuickGenericJniStub() const { 8598 return GetQuickGenericJniStub(); 8599 } 8600 8601 void ClassLinker::SetEntryPointsToCompiledCode(ArtMethod* method, const void* code) const { 8602 CHECK(code != nullptr); 8603 const uint8_t* base = reinterpret_cast<const uint8_t*>(code); // Base of data points at code. 8604 base -= sizeof(void*); // Move backward so that code_offset != 0. 8605 const uint32_t code_offset = sizeof(void*); 8606 OatFile::OatMethod oat_method(base, code_offset); 8607 oat_method.LinkMethod(method); 8608 } 8609 8610 void ClassLinker::SetEntryPointsToInterpreter(ArtMethod* method) const { 8611 if (!method->IsNative()) { 8612 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge()); 8613 } else { 8614 SetEntryPointsToCompiledCode(method, GetQuickGenericJniStub()); 8615 } 8616 } 8617 8618 void ClassLinker::SetEntryPointsForObsoleteMethod(ArtMethod* method) const { 8619 DCHECK(method->IsObsolete()); 8620 // We cannot mess with the entrypoints of native methods because they are used to determine how 8621 // large the method's quick stack frame is. Without this information we cannot walk the stacks. 8622 if (!method->IsNative()) { 8623 method->SetEntryPointFromQuickCompiledCode(GetInvokeObsoleteMethodStub()); 8624 } 8625 } 8626 8627 void ClassLinker::DumpForSigQuit(std::ostream& os) { 8628 ScopedObjectAccess soa(Thread::Current()); 8629 ReaderMutexLock mu(soa.Self(), *Locks::classlinker_classes_lock_); 8630 os << "Zygote loaded classes=" << NumZygoteClasses() << " post zygote classes=" 8631 << NumNonZygoteClasses() << "\n"; 8632 } 8633 8634 class CountClassesVisitor : public ClassLoaderVisitor { 8635 public: 8636 CountClassesVisitor() : num_zygote_classes(0), num_non_zygote_classes(0) {} 8637 8638 void Visit(ObjPtr<mirror::ClassLoader> class_loader) 8639 REQUIRES_SHARED(Locks::classlinker_classes_lock_, Locks::mutator_lock_) OVERRIDE { 8640 ClassTable* const class_table = class_loader->GetClassTable(); 8641 if (class_table != nullptr) { 8642 num_zygote_classes += class_table->NumZygoteClasses(class_loader); 8643 num_non_zygote_classes += class_table->NumNonZygoteClasses(class_loader); 8644 } 8645 } 8646 8647 size_t num_zygote_classes; 8648 size_t num_non_zygote_classes; 8649 }; 8650 8651 size_t ClassLinker::NumZygoteClasses() const { 8652 CountClassesVisitor visitor; 8653 VisitClassLoaders(&visitor); 8654 return visitor.num_zygote_classes + boot_class_table_->NumZygoteClasses(nullptr); 8655 } 8656 8657 size_t ClassLinker::NumNonZygoteClasses() const { 8658 CountClassesVisitor visitor; 8659 VisitClassLoaders(&visitor); 8660 return visitor.num_non_zygote_classes + boot_class_table_->NumNonZygoteClasses(nullptr); 8661 } 8662 8663 size_t ClassLinker::NumLoadedClasses() { 8664 ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_); 8665 // Only return non zygote classes since these are the ones which apps which care about. 8666 return NumNonZygoteClasses(); 8667 } 8668 8669 pid_t ClassLinker::GetClassesLockOwner() { 8670 return Locks::classlinker_classes_lock_->GetExclusiveOwnerTid(); 8671 } 8672 8673 pid_t ClassLinker::GetDexLockOwner() { 8674 return Locks::dex_lock_->GetExclusiveOwnerTid(); 8675 } 8676 8677 void ClassLinker::SetClassRoot(ClassRoot class_root, ObjPtr<mirror::Class> klass) { 8678 DCHECK(!init_done_); 8679 8680 DCHECK(klass != nullptr); 8681 DCHECK(klass->GetClassLoader() == nullptr); 8682 8683 mirror::ObjectArray<mirror::Class>* class_roots = class_roots_.Read(); 8684 DCHECK(class_roots != nullptr); 8685 DCHECK(class_roots->Get(class_root) == nullptr); 8686 class_roots->Set<false>(class_root, klass); 8687 } 8688 8689 const char* ClassLinker::GetClassRootDescriptor(ClassRoot class_root) { 8690 static const char* class_roots_descriptors[] = { 8691 "Ljava/lang/Class;", 8692 "Ljava/lang/Object;", 8693 "[Ljava/lang/Class;", 8694 "[Ljava/lang/Object;", 8695 "Ljava/lang/String;", 8696 "Ljava/lang/DexCache;", 8697 "Ljava/lang/ref/Reference;", 8698 "Ljava/lang/reflect/Constructor;", 8699 "Ljava/lang/reflect/Field;", 8700 "Ljava/lang/reflect/Method;", 8701 "Ljava/lang/reflect/Proxy;", 8702 "[Ljava/lang/String;", 8703 "[Ljava/lang/reflect/Constructor;", 8704 "[Ljava/lang/reflect/Field;", 8705 "[Ljava/lang/reflect/Method;", 8706 "Ljava/lang/invoke/CallSite;", 8707 "Ljava/lang/invoke/MethodHandleImpl;", 8708 "Ljava/lang/invoke/MethodHandles$Lookup;", 8709 "Ljava/lang/invoke/MethodType;", 8710 "Ljava/lang/ClassLoader;", 8711 "Ljava/lang/Throwable;", 8712 "Ljava/lang/ClassNotFoundException;", 8713 "Ljava/lang/StackTraceElement;", 8714 "Ldalvik/system/EmulatedStackFrame;", 8715 "Z", 8716 "B", 8717 "C", 8718 "D", 8719 "F", 8720 "I", 8721 "J", 8722 "S", 8723 "V", 8724 "[Z", 8725 "[B", 8726 "[C", 8727 "[D", 8728 "[F", 8729 "[I", 8730 "[J", 8731 "[S", 8732 "[Ljava/lang/StackTraceElement;", 8733 "Ldalvik/system/ClassExt;", 8734 }; 8735 static_assert(arraysize(class_roots_descriptors) == size_t(kClassRootsMax), 8736 "Mismatch between class descriptors and class-root enum"); 8737 8738 const char* descriptor = class_roots_descriptors[class_root]; 8739 CHECK(descriptor != nullptr); 8740 return descriptor; 8741 } 8742 8743 jobject ClassLinker::CreateWellKnownClassLoader(Thread* self, 8744 const std::vector<const DexFile*>& dex_files, 8745 jclass loader_class, 8746 jobject parent_loader) { 8747 CHECK(self->GetJniEnv()->IsSameObject(loader_class, 8748 WellKnownClasses::dalvik_system_PathClassLoader) || 8749 self->GetJniEnv()->IsSameObject(loader_class, 8750 WellKnownClasses::dalvik_system_DelegateLastClassLoader)); 8751 8752 // SOAAlreadyRunnable is protected, and we need something to add a global reference. 8753 // We could move the jobject to the callers, but all call-sites do this... 8754 ScopedObjectAccessUnchecked soa(self); 8755 8756 // For now, create a libcore-level DexFile for each ART DexFile. This "explodes" multidex. 8757 StackHandleScope<6> hs(self); 8758 8759 ArtField* dex_elements_field = 8760 jni::DecodeArtField(WellKnownClasses::dalvik_system_DexPathList_dexElements); 8761 8762 Handle<mirror::Class> dex_elements_class(hs.NewHandle(dex_elements_field->GetType<true>())); 8763 DCHECK(dex_elements_class != nullptr); 8764 DCHECK(dex_elements_class->IsArrayClass()); 8765 Handle<mirror::ObjectArray<mirror::Object>> h_dex_elements(hs.NewHandle( 8766 mirror::ObjectArray<mirror::Object>::Alloc(self, 8767 dex_elements_class.Get(), 8768 dex_files.size()))); 8769 Handle<mirror::Class> h_dex_element_class = 8770 hs.NewHandle(dex_elements_class->GetComponentType()); 8771 8772 ArtField* element_file_field = 8773 jni::DecodeArtField(WellKnownClasses::dalvik_system_DexPathList__Element_dexFile); 8774 DCHECK_EQ(h_dex_element_class.Get(), element_file_field->GetDeclaringClass()); 8775 8776 ArtField* cookie_field = jni::DecodeArtField(WellKnownClasses::dalvik_system_DexFile_cookie); 8777 DCHECK_EQ(cookie_field->GetDeclaringClass(), element_file_field->GetType<false>()); 8778 8779 ArtField* file_name_field = jni::DecodeArtField(WellKnownClasses::dalvik_system_DexFile_fileName); 8780 DCHECK_EQ(file_name_field->GetDeclaringClass(), element_file_field->GetType<false>()); 8781 8782 // Fill the elements array. 8783 int32_t index = 0; 8784 for (const DexFile* dex_file : dex_files) { 8785 StackHandleScope<4> hs2(self); 8786 8787 // CreateWellKnownClassLoader is only used by gtests and compiler. 8788 // Index 0 of h_long_array is supposed to be the oat file but we can leave it null. 8789 Handle<mirror::LongArray> h_long_array = hs2.NewHandle(mirror::LongArray::Alloc( 8790 self, 8791 kDexFileIndexStart + 1)); 8792 DCHECK(h_long_array != nullptr); 8793 h_long_array->Set(kDexFileIndexStart, reinterpret_cast<intptr_t>(dex_file)); 8794 8795 // Note that this creates a finalizable dalvik.system.DexFile object and a corresponding 8796 // FinalizerReference which will never get cleaned up without a started runtime. 8797 Handle<mirror::Object> h_dex_file = hs2.NewHandle( 8798 cookie_field->GetDeclaringClass()->AllocObject(self)); 8799 DCHECK(h_dex_file != nullptr); 8800 cookie_field->SetObject<false>(h_dex_file.Get(), h_long_array.Get()); 8801 8802 Handle<mirror::String> h_file_name = hs2.NewHandle( 8803 mirror::String::AllocFromModifiedUtf8(self, dex_file->GetLocation().c_str())); 8804 DCHECK(h_file_name != nullptr); 8805 file_name_field->SetObject<false>(h_dex_file.Get(), h_file_name.Get()); 8806 8807 Handle<mirror::Object> h_element = hs2.NewHandle(h_dex_element_class->AllocObject(self)); 8808 DCHECK(h_element != nullptr); 8809 element_file_field->SetObject<false>(h_element.Get(), h_dex_file.Get()); 8810 8811 h_dex_elements->Set(index, h_element.Get()); 8812 index++; 8813 } 8814 DCHECK_EQ(index, h_dex_elements->GetLength()); 8815 8816 // Create DexPathList. 8817 Handle<mirror::Object> h_dex_path_list = hs.NewHandle( 8818 dex_elements_field->GetDeclaringClass()->AllocObject(self)); 8819 DCHECK(h_dex_path_list != nullptr); 8820 // Set elements. 8821 dex_elements_field->SetObject<false>(h_dex_path_list.Get(), h_dex_elements.Get()); 8822 8823 // Create the class loader.. 8824 Handle<mirror::Class> h_loader_class = hs.NewHandle(soa.Decode<mirror::Class>(loader_class)); 8825 Handle<mirror::Object> h_class_loader = hs.NewHandle(h_loader_class->AllocObject(self)); 8826 DCHECK(h_class_loader != nullptr); 8827 // Set DexPathList. 8828 ArtField* path_list_field = 8829 jni::DecodeArtField(WellKnownClasses::dalvik_system_BaseDexClassLoader_pathList); 8830 DCHECK(path_list_field != nullptr); 8831 path_list_field->SetObject<false>(h_class_loader.Get(), h_dex_path_list.Get()); 8832 8833 // Make a pretend boot-classpath. 8834 // TODO: Should we scan the image? 8835 ArtField* const parent_field = 8836 mirror::Class::FindField(self, 8837 h_class_loader->GetClass(), 8838 "parent", 8839 "Ljava/lang/ClassLoader;"); 8840 DCHECK(parent_field != nullptr); 8841 8842 ObjPtr<mirror::Object> parent = (parent_loader != nullptr) 8843 ? soa.Decode<mirror::ClassLoader>(parent_loader) 8844 : soa.Decode<mirror::Class>(WellKnownClasses::java_lang_BootClassLoader)->AllocObject(self); 8845 parent_field->SetObject<false>(h_class_loader.Get(), parent); 8846 8847 // Make it a global ref and return. 8848 ScopedLocalRef<jobject> local_ref( 8849 soa.Env(), soa.Env()->AddLocalReference<jobject>(h_class_loader.Get())); 8850 return soa.Env()->NewGlobalRef(local_ref.get()); 8851 } 8852 8853 jobject ClassLinker::CreatePathClassLoader(Thread* self, 8854 const std::vector<const DexFile*>& dex_files) { 8855 return CreateWellKnownClassLoader(self, 8856 dex_files, 8857 WellKnownClasses::dalvik_system_PathClassLoader, 8858 nullptr); 8859 } 8860 8861 void ClassLinker::DropFindArrayClassCache() { 8862 std::fill_n(find_array_class_cache_, kFindArrayCacheSize, GcRoot<mirror::Class>(nullptr)); 8863 find_array_class_cache_next_victim_ = 0; 8864 } 8865 8866 void ClassLinker::VisitClassLoaders(ClassLoaderVisitor* visitor) const { 8867 Thread* const self = Thread::Current(); 8868 for (const ClassLoaderData& data : class_loaders_) { 8869 // Need to use DecodeJObject so that we get null for cleared JNI weak globals. 8870 ObjPtr<mirror::ClassLoader> class_loader = ObjPtr<mirror::ClassLoader>::DownCast( 8871 self->DecodeJObject(data.weak_root)); 8872 if (class_loader != nullptr) { 8873 visitor->Visit(class_loader.Ptr()); 8874 } 8875 } 8876 } 8877 8878 void ClassLinker::InsertDexFileInToClassLoader(ObjPtr<mirror::Object> dex_file, 8879 ObjPtr<mirror::ClassLoader> class_loader) { 8880 DCHECK(dex_file != nullptr); 8881 Thread* const self = Thread::Current(); 8882 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_); 8883 ClassTable* const table = ClassTableForClassLoader(class_loader.Ptr()); 8884 DCHECK(table != nullptr); 8885 if (table->InsertStrongRoot(dex_file) && class_loader != nullptr) { 8886 // It was not already inserted, perform the write barrier to let the GC know the class loader's 8887 // class table was modified. 8888 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(class_loader); 8889 } 8890 } 8891 8892 void ClassLinker::CleanupClassLoaders() { 8893 Thread* const self = Thread::Current(); 8894 std::vector<ClassLoaderData> to_delete; 8895 // Do the delete outside the lock to avoid lock violation in jit code cache. 8896 { 8897 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_); 8898 for (auto it = class_loaders_.begin(); it != class_loaders_.end(); ) { 8899 const ClassLoaderData& data = *it; 8900 // Need to use DecodeJObject so that we get null for cleared JNI weak globals. 8901 ObjPtr<mirror::ClassLoader> class_loader = 8902 ObjPtr<mirror::ClassLoader>::DownCast(self->DecodeJObject(data.weak_root)); 8903 if (class_loader != nullptr) { 8904 ++it; 8905 } else { 8906 VLOG(class_linker) << "Freeing class loader"; 8907 to_delete.push_back(data); 8908 it = class_loaders_.erase(it); 8909 } 8910 } 8911 } 8912 for (ClassLoaderData& data : to_delete) { 8913 DeleteClassLoader(self, data); 8914 } 8915 } 8916 8917 class GetResolvedClassesVisitor : public ClassVisitor { 8918 public: 8919 GetResolvedClassesVisitor(std::set<DexCacheResolvedClasses>* result, bool ignore_boot_classes) 8920 : result_(result), 8921 ignore_boot_classes_(ignore_boot_classes), 8922 last_resolved_classes_(result->end()), 8923 last_dex_file_(nullptr), 8924 vlog_is_on_(VLOG_IS_ON(class_linker)), 8925 extra_stats_(), 8926 last_extra_stats_(extra_stats_.end()) { } 8927 8928 bool operator()(ObjPtr<mirror::Class> klass) OVERRIDE REQUIRES_SHARED(Locks::mutator_lock_) { 8929 if (!klass->IsProxyClass() && 8930 !klass->IsArrayClass() && 8931 klass->IsResolved() && 8932 !klass->IsErroneousResolved() && 8933 (!ignore_boot_classes_ || klass->GetClassLoader() != nullptr)) { 8934 const DexFile& dex_file = klass->GetDexFile(); 8935 if (&dex_file != last_dex_file_) { 8936 last_dex_file_ = &dex_file; 8937 DexCacheResolvedClasses resolved_classes(dex_file.GetLocation(), 8938 dex_file.GetBaseLocation(), 8939 dex_file.GetLocationChecksum(), 8940 dex_file.NumMethodIds()); 8941 last_resolved_classes_ = result_->find(resolved_classes); 8942 if (last_resolved_classes_ == result_->end()) { 8943 last_resolved_classes_ = result_->insert(resolved_classes).first; 8944 } 8945 } 8946 bool added = last_resolved_classes_->AddClass(klass->GetDexTypeIndex()); 8947 if (UNLIKELY(vlog_is_on_) && added) { 8948 const DexCacheResolvedClasses* resolved_classes = std::addressof(*last_resolved_classes_); 8949 if (last_extra_stats_ == extra_stats_.end() || 8950 last_extra_stats_->first != resolved_classes) { 8951 last_extra_stats_ = extra_stats_.find(resolved_classes); 8952 if (last_extra_stats_ == extra_stats_.end()) { 8953 last_extra_stats_ = 8954 extra_stats_.emplace(resolved_classes, ExtraStats(dex_file.NumClassDefs())).first; 8955 } 8956 } 8957 } 8958 } 8959 return true; 8960 } 8961 8962 void PrintStatistics() const { 8963 if (vlog_is_on_) { 8964 for (const DexCacheResolvedClasses& resolved_classes : *result_) { 8965 auto it = extra_stats_.find(std::addressof(resolved_classes)); 8966 DCHECK(it != extra_stats_.end()); 8967 const ExtraStats& extra_stats = it->second; 8968 LOG(INFO) << "Dex location " << resolved_classes.GetDexLocation() 8969 << " has " << resolved_classes.GetClasses().size() << " / " 8970 << extra_stats.number_of_class_defs_ << " resolved classes"; 8971 } 8972 } 8973 } 8974 8975 private: 8976 struct ExtraStats { 8977 explicit ExtraStats(uint32_t number_of_class_defs) 8978 : number_of_class_defs_(number_of_class_defs) {} 8979 uint32_t number_of_class_defs_; 8980 }; 8981 8982 std::set<DexCacheResolvedClasses>* result_; 8983 bool ignore_boot_classes_; 8984 std::set<DexCacheResolvedClasses>::iterator last_resolved_classes_; 8985 const DexFile* last_dex_file_; 8986 8987 // Statistics. 8988 bool vlog_is_on_; 8989 std::map<const DexCacheResolvedClasses*, ExtraStats> extra_stats_; 8990 std::map<const DexCacheResolvedClasses*, ExtraStats>::iterator last_extra_stats_; 8991 }; 8992 8993 std::set<DexCacheResolvedClasses> ClassLinker::GetResolvedClasses(bool ignore_boot_classes) { 8994 ScopedTrace trace(__PRETTY_FUNCTION__); 8995 ScopedObjectAccess soa(Thread::Current()); 8996 ScopedAssertNoThreadSuspension ants(__FUNCTION__); 8997 std::set<DexCacheResolvedClasses> ret; 8998 VLOG(class_linker) << "Collecting resolved classes"; 8999 const uint64_t start_time = NanoTime(); 9000 GetResolvedClassesVisitor visitor(&ret, ignore_boot_classes); 9001 VisitClasses(&visitor); 9002 if (VLOG_IS_ON(class_linker)) { 9003 visitor.PrintStatistics(); 9004 LOG(INFO) << "Collecting class profile took " << PrettyDuration(NanoTime() - start_time); 9005 } 9006 return ret; 9007 } 9008 9009 class ClassLinker::FindVirtualMethodHolderVisitor : public ClassVisitor { 9010 public: 9011 FindVirtualMethodHolderVisitor(const ArtMethod* method, PointerSize pointer_size) 9012 : method_(method), 9013 pointer_size_(pointer_size) {} 9014 9015 bool operator()(ObjPtr<mirror::Class> klass) REQUIRES_SHARED(Locks::mutator_lock_) OVERRIDE { 9016 if (klass->GetVirtualMethodsSliceUnchecked(pointer_size_).Contains(method_)) { 9017 holder_ = klass; 9018 } 9019 // Return false to stop searching if holder_ is not null. 9020 return holder_ == nullptr; 9021 } 9022 9023 ObjPtr<mirror::Class> holder_ = nullptr; 9024 const ArtMethod* const method_; 9025 const PointerSize pointer_size_; 9026 }; 9027 9028 mirror::Class* ClassLinker::GetHoldingClassOfCopiedMethod(ArtMethod* method) { 9029 ScopedTrace trace(__FUNCTION__); // Since this function is slow, have a trace to notify people. 9030 CHECK(method->IsCopied()); 9031 FindVirtualMethodHolderVisitor visitor(method, image_pointer_size_); 9032 VisitClasses(&visitor); 9033 return visitor.holder_.Ptr(); 9034 } 9035 9036 mirror::IfTable* ClassLinker::AllocIfTable(Thread* self, size_t ifcount) { 9037 return down_cast<mirror::IfTable*>( 9038 mirror::IfTable::Alloc(self, 9039 GetClassRoot(kObjectArrayClass), 9040 ifcount * mirror::IfTable::kMax)); 9041 } 9042 9043 ArtMethod* ClassLinker::FindMethodForProxy(ArtMethod* proxy_method) { 9044 DCHECK(proxy_method->IsProxyMethod()); 9045 { 9046 uint32_t method_index = proxy_method->GetDexMethodIndex(); 9047 PointerSize pointer_size = image_pointer_size_; 9048 Thread* const self = Thread::Current(); 9049 ReaderMutexLock mu(self, *Locks::dex_lock_); 9050 // Locate the dex cache of the original interface/Object 9051 for (const DexCacheData& data : dex_caches_) { 9052 if (!self->IsJWeakCleared(data.weak_root) && 9053 proxy_method->HasSameDexCacheResolvedMethods(data.resolved_methods, pointer_size)) { 9054 ObjPtr<mirror::DexCache> dex_cache = 9055 ObjPtr<mirror::DexCache>::DownCast(self->DecodeJObject(data.weak_root)); 9056 if (dex_cache != nullptr) { 9057 // Lookup up the method. Instead of going through LookupResolvedMethod() 9058 // and thus LookupResolvedType(), use the ClassTable from the DexCacheData. 9059 ArtMethod* resolved_method = dex_cache->GetResolvedMethod(method_index, pointer_size); 9060 if (resolved_method == nullptr) { 9061 const DexFile::MethodId& method_id = data.dex_file->GetMethodId(method_index); 9062 ObjPtr<mirror::Class> klass = dex_cache->GetResolvedType(method_id.class_idx_); 9063 if (klass == nullptr) { 9064 const char* descriptor = data.dex_file->StringByTypeIdx(method_id.class_idx_); 9065 klass = data.class_table->Lookup(descriptor, ComputeModifiedUtf8Hash(descriptor)); 9066 DCHECK(klass != nullptr); 9067 dex_cache->SetResolvedType(method_id.class_idx_, klass); 9068 } 9069 if (klass->IsInterface()) { 9070 resolved_method = klass->FindInterfaceMethod(dex_cache, method_index, pointer_size); 9071 } else { 9072 DCHECK( 9073 klass == WellKnownClasses::ToClass(WellKnownClasses::java_lang_reflect_Proxy) || 9074 klass == WellKnownClasses::ToClass(WellKnownClasses::java_lang_Object)); 9075 resolved_method = klass->FindClassMethod(dex_cache, method_index, pointer_size); 9076 } 9077 CHECK(resolved_method != nullptr); 9078 dex_cache->SetResolvedMethod(method_index, resolved_method, pointer_size); 9079 } 9080 return resolved_method; 9081 } 9082 } 9083 } 9084 } 9085 // Note: Do not use proxy_method->PrettyMethod() as it can call back here. 9086 LOG(FATAL) << "Didn't find dex cache for " << proxy_method->GetDeclaringClass()->PrettyClass(); 9087 UNREACHABLE(); 9088 } 9089 9090 // Instantiate ResolveMethod. 9091 template ArtMethod* ClassLinker::ResolveMethod<ClassLinker::ResolveMode::kCheckICCEAndIAE>( 9092 const DexFile& dex_file, 9093 uint32_t method_idx, 9094 Handle<mirror::DexCache> dex_cache, 9095 Handle<mirror::ClassLoader> class_loader, 9096 ArtMethod* referrer, 9097 InvokeType type); 9098 template ArtMethod* ClassLinker::ResolveMethod<ClassLinker::ResolveMode::kNoChecks>( 9099 const DexFile& dex_file, 9100 uint32_t method_idx, 9101 Handle<mirror::DexCache> dex_cache, 9102 Handle<mirror::ClassLoader> class_loader, 9103 ArtMethod* referrer, 9104 InvokeType type); 9105 9106 } // namespace art 9107