2 * Copyright (C) 2011 The Android Open Source Project
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
17 #include "class_linker.h"
28 #include <unordered_map>
32 #include "android-base/stringprintf.h"
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"
47 #include "class_linker-inl.h"
48 #include "class_table-inl.h"
49 #include "compiler_callbacks.h"
51 #include "dex_file-inl.h"
52 #include "entrypoints/entrypoint_utils.h"
53 #include "entrypoints/runtime_asm_entrypoints.h"
54 #include "experimental_flags.h"
55 #include "gc_root-inl.h"
56 #include "gc/accounting/card_table-inl.h"
57 #include "gc/accounting/heap_bitmap-inl.h"
59 #include "gc/scoped_gc_critical_section.h"
60 #include "gc/space/image_space.h"
61 #include "handle_scope-inl.h"
62 #include "image-inl.h"
63 #include "imt_conflict_table.h"
64 #include "imtable-inl.h"
65 #include "intern_table.h"
66 #include "interpreter/interpreter.h"
68 #include "jit/jit_code_cache.h"
69 #include "jit/profile_compilation_info.h"
70 #include "jni_internal.h"
72 #include "linear_alloc.h"
73 #include "mirror/class.h"
74 #include "mirror/class-inl.h"
75 #include "mirror/class_ext.h"
76 #include "mirror/class_loader.h"
77 #include "mirror/dex_cache.h"
78 #include "mirror/dex_cache-inl.h"
79 #include "mirror/emulated_stack_frame.h"
80 #include "mirror/field.h"
81 #include "mirror/iftable-inl.h"
82 #include "mirror/method.h"
83 #include "mirror/method_type.h"
84 #include "mirror/method_handle_impl.h"
85 #include "mirror/object-inl.h"
86 #include "mirror/object_array-inl.h"
87 #include "mirror/proxy.h"
88 #include "mirror/reference-inl.h"
89 #include "mirror/stack_trace_element.h"
90 #include "mirror/string-inl.h"
91 #include "native/dalvik_system_DexFile.h"
94 #include "oat_file-inl.h"
95 #include "oat_file_assistant.h"
96 #include "oat_file_manager.h"
97 #include "object_lock.h"
100 #include "runtime_callbacks.h"
101 #include "ScopedLocalRef.h"
102 #include "scoped_thread_state_change-inl.h"
103 #include "thread-inl.h"
104 #include "thread_list.h"
107 #include "utils/dex_cache_arrays_layout-inl.h"
108 #include "verifier/method_verifier.h"
109 #include "well_known_classes.h"
113 using android::base::StringPrintf;
115 static constexpr bool kSanityCheckObjects = kIsDebugBuild;
116 static constexpr bool kVerifyArtMethodDeclaringClasses = kIsDebugBuild;
118 static void ThrowNoClassDefFoundError(const char* fmt, ...)
119 __attribute__((__format__(__printf__, 1, 2)))
120 REQUIRES_SHARED(Locks::mutator_lock_);
121 static void ThrowNoClassDefFoundError(const char* fmt, ...) {
124 Thread* self = Thread::Current();
125 self->ThrowNewExceptionV("Ljava/lang/NoClassDefFoundError;", fmt, args);
129 static bool HasInitWithString(Thread* self, ClassLinker* class_linker, const char* descriptor)
130 REQUIRES_SHARED(Locks::mutator_lock_) {
131 ArtMethod* method = self->GetCurrentMethod(nullptr);
132 StackHandleScope<1> hs(self);
133 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(method != nullptr ?
134 method->GetDeclaringClass()->GetClassLoader() : nullptr));
135 ObjPtr<mirror::Class> exception_class = class_linker->FindClass(self, descriptor, class_loader);
137 if (exception_class == nullptr) {
138 // No exc class ~ no <init>-with-string.
139 CHECK(self->IsExceptionPending());
140 self->ClearException();
144 ArtMethod* exception_init_method = exception_class->FindDeclaredDirectMethod(
145 "<init>", "(Ljava/lang/String;)V", class_linker->GetImagePointerSize());
146 return exception_init_method != nullptr;
149 static mirror::Object* GetVerifyError(ObjPtr<mirror::Class> c)
150 REQUIRES_SHARED(Locks::mutator_lock_) {
151 ObjPtr<mirror::ClassExt> ext(c->GetExtData());
152 if (ext == nullptr) {
155 return ext->GetVerifyError();
159 // Helper for ThrowEarlierClassFailure. Throws the stored error.
160 static void HandleEarlierVerifyError(Thread* self,
161 ClassLinker* class_linker,
162 ObjPtr<mirror::Class> c)
163 REQUIRES_SHARED(Locks::mutator_lock_) {
164 ObjPtr<mirror::Object> obj = GetVerifyError(c);
165 DCHECK(obj != nullptr);
166 self->AssertNoPendingException();
167 if (obj->IsClass()) {
168 // Previous error has been stored as class. Create a new exception of that type.
170 // It's possible the exception doesn't have a <init>(String).
172 const char* descriptor = obj->AsClass()->GetDescriptor(&temp);
174 if (HasInitWithString(self, class_linker, descriptor)) {
175 self->ThrowNewException(descriptor, c->PrettyDescriptor().c_str());
177 self->ThrowNewException(descriptor, nullptr);
180 // Previous error has been stored as an instance. Just rethrow.
181 ObjPtr<mirror::Class> throwable_class =
182 self->DecodeJObject(WellKnownClasses::java_lang_Throwable)->AsClass();
183 ObjPtr<mirror::Class> error_class = obj->GetClass();
184 CHECK(throwable_class->IsAssignableFrom(error_class));
185 self->SetException(obj->AsThrowable());
187 self->AssertPendingException();
190 void ClassLinker::ThrowEarlierClassFailure(ObjPtr<mirror::Class> c, bool wrap_in_no_class_def) {
191 // The class failed to initialize on a previous attempt, so we want to throw
192 // a NoClassDefFoundError (v2 2.17.5). The exception to this rule is if we
193 // failed in verification, in which case v2 5.4.1 says we need to re-throw
194 // the previous error.
195 Runtime* const runtime = Runtime::Current();
196 if (!runtime->IsAotCompiler()) { // Give info if this occurs at runtime.
198 if (GetVerifyError(c) != nullptr) {
199 ObjPtr<mirror::Object> verify_error = GetVerifyError(c);
200 if (verify_error->IsClass()) {
201 extra = mirror::Class::PrettyDescriptor(verify_error->AsClass());
203 extra = verify_error->AsThrowable()->Dump();
206 LOG(INFO) << "Rejecting re-init on previously-failed class " << c->PrettyClass()
210 CHECK(c->IsErroneous()) << c->PrettyClass() << " " << c->GetStatus();
211 Thread* self = Thread::Current();
212 if (runtime->IsAotCompiler()) {
213 // At compile time, accurate errors and NCDFE are disabled to speed compilation.
214 ObjPtr<mirror::Throwable> pre_allocated = runtime->GetPreAllocatedNoClassDefFoundError();
215 self->SetException(pre_allocated);
217 if (GetVerifyError(c) != nullptr) {
218 // Rethrow stored error.
219 HandleEarlierVerifyError(self, this, c);
221 // TODO This might be wrong if we hit an OOME while allocating the ClassExt. In that case we
222 // might have meant to go down the earlier if statement with the original error but it got
223 // swallowed by the OOM so we end up here.
224 if (GetVerifyError(c) == nullptr || wrap_in_no_class_def) {
225 // If there isn't a recorded earlier error, or this is a repeat throw from initialization,
226 // the top-level exception must be a NoClassDefFoundError. The potentially already pending
227 // exception will be a cause.
228 self->ThrowNewWrappedException("Ljava/lang/NoClassDefFoundError;",
229 c->PrettyDescriptor().c_str());
234 static void VlogClassInitializationFailure(Handle<mirror::Class> klass)
235 REQUIRES_SHARED(Locks::mutator_lock_) {
236 if (VLOG_IS_ON(class_linker)) {
238 LOG(INFO) << "Failed to initialize class " << klass->GetDescriptor(&temp) << " from "
239 << klass->GetLocation() << "\n" << Thread::Current()->GetException()->Dump();
243 static void WrapExceptionInInitializer(Handle<mirror::Class> klass)
244 REQUIRES_SHARED(Locks::mutator_lock_) {
245 Thread* self = Thread::Current();
246 JNIEnv* env = self->GetJniEnv();
248 ScopedLocalRef<jthrowable> cause(env, env->ExceptionOccurred());
249 CHECK(cause.get() != nullptr);
251 // Boot classpath classes should not fail initialization. This is a sanity debug check. This
252 // cannot in general be guaranteed, but in all likelihood leads to breakage down the line.
253 if (klass->GetClassLoader() == nullptr && !Runtime::Current()->IsAotCompiler()) {
255 LOG(kIsDebugBuild ? FATAL : WARNING) << klass->GetDescriptor(&tmp) << " failed initialization";
258 env->ExceptionClear();
259 bool is_error = env->IsInstanceOf(cause.get(), WellKnownClasses::java_lang_Error);
260 env->Throw(cause.get());
262 // We only wrap non-Error exceptions; an Error can just be used as-is.
264 self->ThrowNewWrappedException("Ljava/lang/ExceptionInInitializerError;", nullptr);
266 VlogClassInitializationFailure(klass);
269 // Gap between two fields in object layout.
271 uint32_t start_offset; // The offset from the start of the object.
272 uint32_t size; // The gap size of 1, 2, or 4 bytes.
274 struct FieldGapsComparator {
275 explicit FieldGapsComparator() {
277 bool operator() (const FieldGap& lhs, const FieldGap& rhs)
278 NO_THREAD_SAFETY_ANALYSIS {
279 // Sort by gap size, largest first. Secondary sort by starting offset.
280 // Note that the priority queue returns the largest element, so operator()
281 // should return true if lhs is less than rhs.
282 return lhs.size < rhs.size || (lhs.size == rhs.size && lhs.start_offset > rhs.start_offset);
285 typedef std::priority_queue<FieldGap, std::vector<FieldGap>, FieldGapsComparator> FieldGaps;
287 // Adds largest aligned gaps to queue of gaps.
288 static void AddFieldGap(uint32_t gap_start, uint32_t gap_end, FieldGaps* gaps) {
289 DCHECK(gaps != nullptr);
291 uint32_t current_offset = gap_start;
292 while (current_offset != gap_end) {
293 size_t remaining = gap_end - current_offset;
294 if (remaining >= sizeof(uint32_t) && IsAligned<4>(current_offset)) {
295 gaps->push(FieldGap {current_offset, sizeof(uint32_t)});
296 current_offset += sizeof(uint32_t);
297 } else if (remaining >= sizeof(uint16_t) && IsAligned<2>(current_offset)) {
298 gaps->push(FieldGap {current_offset, sizeof(uint16_t)});
299 current_offset += sizeof(uint16_t);
301 gaps->push(FieldGap {current_offset, sizeof(uint8_t)});
302 current_offset += sizeof(uint8_t);
304 DCHECK_LE(current_offset, gap_end) << "Overran gap";
307 // Shuffle fields forward, making use of gaps whenever possible.
309 static void ShuffleForward(size_t* current_field_idx,
310 MemberOffset* field_offset,
311 std::deque<ArtField*>* grouped_and_sorted_fields,
313 REQUIRES_SHARED(Locks::mutator_lock_) {
314 DCHECK(current_field_idx != nullptr);
315 DCHECK(grouped_and_sorted_fields != nullptr);
316 DCHECK(gaps != nullptr);
317 DCHECK(field_offset != nullptr);
319 DCHECK(IsPowerOfTwo(n));
320 while (!grouped_and_sorted_fields->empty()) {
321 ArtField* field = grouped_and_sorted_fields->front();
322 Primitive::Type type = field->GetTypeAsPrimitiveType();
323 if (Primitive::ComponentSize(type) < n) {
326 if (!IsAligned<n>(field_offset->Uint32Value())) {
327 MemberOffset old_offset = *field_offset;
328 *field_offset = MemberOffset(RoundUp(field_offset->Uint32Value(), n));
329 AddFieldGap(old_offset.Uint32Value(), field_offset->Uint32Value(), gaps);
331 CHECK(type != Primitive::kPrimNot) << field->PrettyField(); // should be primitive types
332 grouped_and_sorted_fields->pop_front();
333 if (!gaps->empty() && gaps->top().size >= n) {
334 FieldGap gap = gaps->top();
336 DCHECK_ALIGNED(gap.start_offset, n);
337 field->SetOffset(MemberOffset(gap.start_offset));
339 AddFieldGap(gap.start_offset + n, gap.start_offset + gap.size, gaps);
342 DCHECK_ALIGNED(field_offset->Uint32Value(), n);
343 field->SetOffset(*field_offset);
344 *field_offset = MemberOffset(field_offset->Uint32Value() + n);
346 ++(*current_field_idx);
350 ClassLinker::ClassLinker(InternTable* intern_table)
351 : failed_dex_cache_class_lookups_(0),
352 class_roots_(nullptr),
353 array_iftable_(nullptr),
354 find_array_class_cache_next_victim_(0),
356 log_new_roots_(false),
357 intern_table_(intern_table),
358 quick_resolution_trampoline_(nullptr),
359 quick_imt_conflict_trampoline_(nullptr),
360 quick_generic_jni_trampoline_(nullptr),
361 quick_to_interpreter_bridge_trampoline_(nullptr),
362 image_pointer_size_(kRuntimePointerSize) {
363 CHECK(intern_table_ != nullptr);
364 static_assert(kFindArrayCacheSize == arraysize(find_array_class_cache_),
365 "Array cache size wrong.");
366 std::fill_n(find_array_class_cache_, kFindArrayCacheSize, GcRoot<mirror::Class>(nullptr));
369 void ClassLinker::CheckSystemClass(Thread* self, Handle<mirror::Class> c1, const char* descriptor) {
370 ObjPtr<mirror::Class> c2 = FindSystemClass(self, descriptor);
372 LOG(FATAL) << "Could not find class " << descriptor;
375 if (c1.Get() != c2) {
376 std::ostringstream os1, os2;
377 c1->DumpClass(os1, mirror::Class::kDumpClassFullDetail);
378 c2->DumpClass(os2, mirror::Class::kDumpClassFullDetail);
379 LOG(FATAL) << "InitWithoutImage: Class mismatch for " << descriptor
380 << ". This is most likely the result of a broken build. Make sure that "
381 << "libcore and art projects match.\n\n"
382 << os1.str() << "\n\n" << os2.str();
387 bool ClassLinker::InitWithoutImage(std::vector<std::unique_ptr<const DexFile>> boot_class_path,
388 std::string* error_msg) {
389 VLOG(startup) << "ClassLinker::Init";
391 Thread* const self = Thread::Current();
392 Runtime* const runtime = Runtime::Current();
393 gc::Heap* const heap = runtime->GetHeap();
395 CHECK(!heap->HasBootImageSpace()) << "Runtime has image. We should use it.";
398 // Use the pointer size from the runtime since we are probably creating the image.
399 image_pointer_size_ = InstructionSetPointerSize(runtime->GetInstructionSet());
401 // java_lang_Class comes first, it's needed for AllocClass
402 // The GC can't handle an object with a null class since we can't get the size of this object.
403 heap->IncrementDisableMovingGC(self);
404 StackHandleScope<64> hs(self); // 64 is picked arbitrarily.
405 auto class_class_size = mirror::Class::ClassClassSize(image_pointer_size_);
406 Handle<mirror::Class> java_lang_Class(hs.NewHandle(down_cast<mirror::Class*>(
407 heap->AllocNonMovableObject<true>(self, nullptr, class_class_size, VoidFunctor()))));
408 CHECK(java_lang_Class.Get() != nullptr);
409 mirror::Class::SetClassClass(java_lang_Class.Get());
410 java_lang_Class->SetClass(java_lang_Class.Get());
411 if (kUseBakerReadBarrier) {
412 java_lang_Class->AssertReadBarrierState();
414 java_lang_Class->SetClassSize(class_class_size);
415 java_lang_Class->SetPrimitiveType(Primitive::kPrimNot);
416 heap->DecrementDisableMovingGC(self);
417 // AllocClass(ObjPtr<mirror::Class>) can now be used
419 // Class[] is used for reflection support.
420 auto class_array_class_size = mirror::ObjectArray<mirror::Class>::ClassSize(image_pointer_size_);
421 Handle<mirror::Class> class_array_class(hs.NewHandle(
422 AllocClass(self, java_lang_Class.Get(), class_array_class_size)));
423 class_array_class->SetComponentType(java_lang_Class.Get());
425 // java_lang_Object comes next so that object_array_class can be created.
426 Handle<mirror::Class> java_lang_Object(hs.NewHandle(
427 AllocClass(self, java_lang_Class.Get(), mirror::Object::ClassSize(image_pointer_size_))));
428 CHECK(java_lang_Object.Get() != nullptr);
429 // backfill Object as the super class of Class.
430 java_lang_Class->SetSuperClass(java_lang_Object.Get());
431 mirror::Class::SetStatus(java_lang_Object, mirror::Class::kStatusLoaded, self);
433 java_lang_Object->SetObjectSize(sizeof(mirror::Object));
434 // Allocate in non-movable so that it's possible to check if a JNI weak global ref has been
435 // cleared without triggering the read barrier and unintentionally mark the sentinel alive.
436 runtime->SetSentinel(heap->AllocNonMovableObject<true>(self,
437 java_lang_Object.Get(),
438 java_lang_Object->GetObjectSize(),
441 // Object[] next to hold class roots.
442 Handle<mirror::Class> object_array_class(hs.NewHandle(
443 AllocClass(self, java_lang_Class.Get(),
444 mirror::ObjectArray<mirror::Object>::ClassSize(image_pointer_size_))));
445 object_array_class->SetComponentType(java_lang_Object.Get());
447 // Setup the char (primitive) class to be used for char[].
448 Handle<mirror::Class> char_class(hs.NewHandle(
449 AllocClass(self, java_lang_Class.Get(),
450 mirror::Class::PrimitiveClassSize(image_pointer_size_))));
451 // The primitive char class won't be initialized by
452 // InitializePrimitiveClass until line 459, but strings (and
453 // internal char arrays) will be allocated before that and the
454 // component size, which is computed from the primitive type, needs
456 char_class->SetPrimitiveType(Primitive::kPrimChar);
458 // Setup the char[] class to be used for String.
459 Handle<mirror::Class> char_array_class(hs.NewHandle(
460 AllocClass(self, java_lang_Class.Get(), mirror::Array::ClassSize(image_pointer_size_))));
461 char_array_class->SetComponentType(char_class.Get());
462 mirror::CharArray::SetArrayClass(char_array_class.Get());
465 Handle<mirror::Class> java_lang_String(hs.NewHandle(
466 AllocClass(self, java_lang_Class.Get(), mirror::String::ClassSize(image_pointer_size_))));
467 java_lang_String->SetStringClass();
468 mirror::String::SetClass(java_lang_String.Get());
469 mirror::Class::SetStatus(java_lang_String, mirror::Class::kStatusResolved, self);
471 // Setup java.lang.ref.Reference.
472 Handle<mirror::Class> java_lang_ref_Reference(hs.NewHandle(
473 AllocClass(self, java_lang_Class.Get(), mirror::Reference::ClassSize(image_pointer_size_))));
474 mirror::Reference::SetClass(java_lang_ref_Reference.Get());
475 java_lang_ref_Reference->SetObjectSize(mirror::Reference::InstanceSize());
476 mirror::Class::SetStatus(java_lang_ref_Reference, mirror::Class::kStatusResolved, self);
478 // Create storage for root classes, save away our work so far (requires descriptors).
479 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class>>(
480 mirror::ObjectArray<mirror::Class>::Alloc(self, object_array_class.Get(),
482 CHECK(!class_roots_.IsNull());
483 SetClassRoot(kJavaLangClass, java_lang_Class.Get());
484 SetClassRoot(kJavaLangObject, java_lang_Object.Get());
485 SetClassRoot(kClassArrayClass, class_array_class.Get());
486 SetClassRoot(kObjectArrayClass, object_array_class.Get());
487 SetClassRoot(kCharArrayClass, char_array_class.Get());
488 SetClassRoot(kJavaLangString, java_lang_String.Get());
489 SetClassRoot(kJavaLangRefReference, java_lang_ref_Reference.Get());
491 // Fill in the empty iftable. Needs to be done after the kObjectArrayClass root is set.
492 java_lang_Object->SetIfTable(AllocIfTable(self, 0));
494 // Setup the primitive type classes.
495 SetClassRoot(kPrimitiveBoolean, CreatePrimitiveClass(self, Primitive::kPrimBoolean));
496 SetClassRoot(kPrimitiveByte, CreatePrimitiveClass(self, Primitive::kPrimByte));
497 SetClassRoot(kPrimitiveShort, CreatePrimitiveClass(self, Primitive::kPrimShort));
498 SetClassRoot(kPrimitiveInt, CreatePrimitiveClass(self, Primitive::kPrimInt));
499 SetClassRoot(kPrimitiveLong, CreatePrimitiveClass(self, Primitive::kPrimLong));
500 SetClassRoot(kPrimitiveFloat, CreatePrimitiveClass(self, Primitive::kPrimFloat));
501 SetClassRoot(kPrimitiveDouble, CreatePrimitiveClass(self, Primitive::kPrimDouble));
502 SetClassRoot(kPrimitiveVoid, CreatePrimitiveClass(self, Primitive::kPrimVoid));
504 // Create array interface entries to populate once we can load system classes.
505 array_iftable_ = GcRoot<mirror::IfTable>(AllocIfTable(self, 2));
507 // Create int array type for AllocDexCache (done in AppendToBootClassPath).
508 Handle<mirror::Class> int_array_class(hs.NewHandle(
509 AllocClass(self, java_lang_Class.Get(), mirror::Array::ClassSize(image_pointer_size_))));
510 int_array_class->SetComponentType(GetClassRoot(kPrimitiveInt));
511 mirror::IntArray::SetArrayClass(int_array_class.Get());
512 SetClassRoot(kIntArrayClass, int_array_class.Get());
514 // Create long array type for AllocDexCache (done in AppendToBootClassPath).
515 Handle<mirror::Class> long_array_class(hs.NewHandle(
516 AllocClass(self, java_lang_Class.Get(), mirror::Array::ClassSize(image_pointer_size_))));
517 long_array_class->SetComponentType(GetClassRoot(kPrimitiveLong));
518 mirror::LongArray::SetArrayClass(long_array_class.Get());
519 SetClassRoot(kLongArrayClass, long_array_class.Get());
521 // now that these are registered, we can use AllocClass() and AllocObjectArray
523 // Set up DexCache. This cannot be done later since AppendToBootClassPath calls AllocDexCache.
524 Handle<mirror::Class> java_lang_DexCache(hs.NewHandle(
525 AllocClass(self, java_lang_Class.Get(), mirror::DexCache::ClassSize(image_pointer_size_))));
526 SetClassRoot(kJavaLangDexCache, java_lang_DexCache.Get());
527 java_lang_DexCache->SetDexCacheClass();
528 java_lang_DexCache->SetObjectSize(mirror::DexCache::InstanceSize());
529 mirror::Class::SetStatus(java_lang_DexCache, mirror::Class::kStatusResolved, self);
532 // Setup dalvik.system.ClassExt
533 Handle<mirror::Class> dalvik_system_ClassExt(hs.NewHandle(
534 AllocClass(self, java_lang_Class.Get(), mirror::ClassExt::ClassSize(image_pointer_size_))));
535 SetClassRoot(kDalvikSystemClassExt, dalvik_system_ClassExt.Get());
536 mirror::ClassExt::SetClass(dalvik_system_ClassExt.Get());
537 mirror::Class::SetStatus(dalvik_system_ClassExt, mirror::Class::kStatusResolved, self);
539 // Set up array classes for string, field, method
540 Handle<mirror::Class> object_array_string(hs.NewHandle(
541 AllocClass(self, java_lang_Class.Get(),
542 mirror::ObjectArray<mirror::String>::ClassSize(image_pointer_size_))));
543 object_array_string->SetComponentType(java_lang_String.Get());
544 SetClassRoot(kJavaLangStringArrayClass, object_array_string.Get());
546 LinearAlloc* linear_alloc = runtime->GetLinearAlloc();
547 // Create runtime resolution and imt conflict methods.
548 runtime->SetResolutionMethod(runtime->CreateResolutionMethod());
549 runtime->SetImtConflictMethod(runtime->CreateImtConflictMethod(linear_alloc));
550 runtime->SetImtUnimplementedMethod(runtime->CreateImtConflictMethod(linear_alloc));
552 // Setup boot_class_path_ and register class_path now that we can use AllocObjectArray to create
553 // DexCache instances. Needs to be after String, Field, Method arrays since AllocDexCache uses
555 if (boot_class_path.empty()) {
556 *error_msg = "Boot classpath is empty.";
559 for (auto& dex_file : boot_class_path) {
560 if (dex_file.get() == nullptr) {
561 *error_msg = "Null dex file.";
564 AppendToBootClassPath(self, *dex_file);
565 boot_dex_files_.push_back(std::move(dex_file));
568 // now we can use FindSystemClass
570 // run char class through InitializePrimitiveClass to finish init
571 InitializePrimitiveClass(char_class.Get(), Primitive::kPrimChar);
572 SetClassRoot(kPrimitiveChar, char_class.Get()); // needs descriptor
574 // Set up GenericJNI entrypoint. That is mainly a hack for common_compiler_test.h so that
575 // we do not need friend classes or a publicly exposed setter.
576 quick_generic_jni_trampoline_ = GetQuickGenericJniStub();
577 if (!runtime->IsAotCompiler()) {
578 // We need to set up the generic trampolines since we don't have an image.
579 quick_resolution_trampoline_ = GetQuickResolutionStub();
580 quick_imt_conflict_trampoline_ = GetQuickImtConflictStub();
581 quick_to_interpreter_bridge_trampoline_ = GetQuickToInterpreterBridge();
584 // Object, String, ClassExt and DexCache need to be rerun through FindSystemClass to finish init
585 mirror::Class::SetStatus(java_lang_Object, mirror::Class::kStatusNotReady, self);
586 CheckSystemClass(self, java_lang_Object, "Ljava/lang/Object;");
587 CHECK_EQ(java_lang_Object->GetObjectSize(), mirror::Object::InstanceSize());
588 mirror::Class::SetStatus(java_lang_String, mirror::Class::kStatusNotReady, self);
589 CheckSystemClass(self, java_lang_String, "Ljava/lang/String;");
590 mirror::Class::SetStatus(java_lang_DexCache, mirror::Class::kStatusNotReady, self);
591 CheckSystemClass(self, java_lang_DexCache, "Ljava/lang/DexCache;");
592 CHECK_EQ(java_lang_DexCache->GetObjectSize(), mirror::DexCache::InstanceSize());
593 mirror::Class::SetStatus(dalvik_system_ClassExt, mirror::Class::kStatusNotReady, self);
594 CheckSystemClass(self, dalvik_system_ClassExt, "Ldalvik/system/ClassExt;");
595 CHECK_EQ(dalvik_system_ClassExt->GetObjectSize(), mirror::ClassExt::InstanceSize());
597 // Setup the primitive array type classes - can't be done until Object has a vtable.
598 SetClassRoot(kBooleanArrayClass, FindSystemClass(self, "[Z"));
599 mirror::BooleanArray::SetArrayClass(GetClassRoot(kBooleanArrayClass));
601 SetClassRoot(kByteArrayClass, FindSystemClass(self, "[B"));
602 mirror::ByteArray::SetArrayClass(GetClassRoot(kByteArrayClass));
604 CheckSystemClass(self, char_array_class, "[C");
606 SetClassRoot(kShortArrayClass, FindSystemClass(self, "[S"));
607 mirror::ShortArray::SetArrayClass(GetClassRoot(kShortArrayClass));
609 CheckSystemClass(self, int_array_class, "[I");
610 CheckSystemClass(self, long_array_class, "[J");
612 SetClassRoot(kFloatArrayClass, FindSystemClass(self, "[F"));
613 mirror::FloatArray::SetArrayClass(GetClassRoot(kFloatArrayClass));
615 SetClassRoot(kDoubleArrayClass, FindSystemClass(self, "[D"));
616 mirror::DoubleArray::SetArrayClass(GetClassRoot(kDoubleArrayClass));
618 // Run Class through FindSystemClass. This initializes the dex_cache_ fields and register it
620 CheckSystemClass(self, java_lang_Class, "Ljava/lang/Class;");
622 CheckSystemClass(self, class_array_class, "[Ljava/lang/Class;");
623 CheckSystemClass(self, object_array_class, "[Ljava/lang/Object;");
625 // Setup the single, global copy of "iftable".
626 auto java_lang_Cloneable = hs.NewHandle(FindSystemClass(self, "Ljava/lang/Cloneable;"));
627 CHECK(java_lang_Cloneable.Get() != nullptr);
628 auto java_io_Serializable = hs.NewHandle(FindSystemClass(self, "Ljava/io/Serializable;"));
629 CHECK(java_io_Serializable.Get() != nullptr);
630 // We assume that Cloneable/Serializable don't have superinterfaces -- normally we'd have to
631 // crawl up and explicitly list all of the supers as well.
632 array_iftable_.Read()->SetInterface(0, java_lang_Cloneable.Get());
633 array_iftable_.Read()->SetInterface(1, java_io_Serializable.Get());
635 // Sanity check Class[] and Object[]'s interfaces. GetDirectInterface may cause thread
637 CHECK_EQ(java_lang_Cloneable.Get(),
638 mirror::Class::GetDirectInterface(self, class_array_class.Get(), 0));
639 CHECK_EQ(java_io_Serializable.Get(),
640 mirror::Class::GetDirectInterface(self, class_array_class.Get(), 1));
641 CHECK_EQ(java_lang_Cloneable.Get(),
642 mirror::Class::GetDirectInterface(self, object_array_class.Get(), 0));
643 CHECK_EQ(java_io_Serializable.Get(),
644 mirror::Class::GetDirectInterface(self, object_array_class.Get(), 1));
646 CHECK_EQ(object_array_string.Get(),
647 FindSystemClass(self, GetClassRootDescriptor(kJavaLangStringArrayClass)));
649 // End of special init trickery, all subsequent classes may be loaded via FindSystemClass.
651 // Create java.lang.reflect.Proxy root.
652 SetClassRoot(kJavaLangReflectProxy, FindSystemClass(self, "Ljava/lang/reflect/Proxy;"));
654 // Create java.lang.reflect.Field.class root.
655 auto* class_root = FindSystemClass(self, "Ljava/lang/reflect/Field;");
656 CHECK(class_root != nullptr);
657 SetClassRoot(kJavaLangReflectField, class_root);
658 mirror::Field::SetClass(class_root);
660 // Create java.lang.reflect.Field array root.
661 class_root = FindSystemClass(self, "[Ljava/lang/reflect/Field;");
662 CHECK(class_root != nullptr);
663 SetClassRoot(kJavaLangReflectFieldArrayClass, class_root);
664 mirror::Field::SetArrayClass(class_root);
666 // Create java.lang.reflect.Constructor.class root and array root.
667 class_root = FindSystemClass(self, "Ljava/lang/reflect/Constructor;");
668 CHECK(class_root != nullptr);
669 SetClassRoot(kJavaLangReflectConstructor, class_root);
670 mirror::Constructor::SetClass(class_root);
671 class_root = FindSystemClass(self, "[Ljava/lang/reflect/Constructor;");
672 CHECK(class_root != nullptr);
673 SetClassRoot(kJavaLangReflectConstructorArrayClass, class_root);
674 mirror::Constructor::SetArrayClass(class_root);
676 // Create java.lang.reflect.Method.class root and array root.
677 class_root = FindSystemClass(self, "Ljava/lang/reflect/Method;");
678 CHECK(class_root != nullptr);
679 SetClassRoot(kJavaLangReflectMethod, class_root);
680 mirror::Method::SetClass(class_root);
681 class_root = FindSystemClass(self, "[Ljava/lang/reflect/Method;");
682 CHECK(class_root != nullptr);
683 SetClassRoot(kJavaLangReflectMethodArrayClass, class_root);
684 mirror::Method::SetArrayClass(class_root);
686 // Create java.lang.invoke.MethodType.class root
687 class_root = FindSystemClass(self, "Ljava/lang/invoke/MethodType;");
688 CHECK(class_root != nullptr);
689 SetClassRoot(kJavaLangInvokeMethodType, class_root);
690 mirror::MethodType::SetClass(class_root);
692 // Create java.lang.invoke.MethodHandleImpl.class root
693 class_root = FindSystemClass(self, "Ljava/lang/invoke/MethodHandleImpl;");
694 CHECK(class_root != nullptr);
695 SetClassRoot(kJavaLangInvokeMethodHandleImpl, class_root);
696 mirror::MethodHandleImpl::SetClass(class_root);
698 class_root = FindSystemClass(self, "Ldalvik/system/EmulatedStackFrame;");
699 CHECK(class_root != nullptr);
700 SetClassRoot(kDalvikSystemEmulatedStackFrame, class_root);
701 mirror::EmulatedStackFrame::SetClass(class_root);
703 // java.lang.ref classes need to be specially flagged, but otherwise are normal classes
704 // finish initializing Reference class
705 mirror::Class::SetStatus(java_lang_ref_Reference, mirror::Class::kStatusNotReady, self);
706 CheckSystemClass(self, java_lang_ref_Reference, "Ljava/lang/ref/Reference;");
707 CHECK_EQ(java_lang_ref_Reference->GetObjectSize(), mirror::Reference::InstanceSize());
708 CHECK_EQ(java_lang_ref_Reference->GetClassSize(),
709 mirror::Reference::ClassSize(image_pointer_size_));
710 class_root = FindSystemClass(self, "Ljava/lang/ref/FinalizerReference;");
711 CHECK_EQ(class_root->GetClassFlags(), mirror::kClassFlagNormal);
712 class_root->SetClassFlags(class_root->GetClassFlags() | mirror::kClassFlagFinalizerReference);
713 class_root = FindSystemClass(self, "Ljava/lang/ref/PhantomReference;");
714 CHECK_EQ(class_root->GetClassFlags(), mirror::kClassFlagNormal);
715 class_root->SetClassFlags(class_root->GetClassFlags() | mirror::kClassFlagPhantomReference);
716 class_root = FindSystemClass(self, "Ljava/lang/ref/SoftReference;");
717 CHECK_EQ(class_root->GetClassFlags(), mirror::kClassFlagNormal);
718 class_root->SetClassFlags(class_root->GetClassFlags() | mirror::kClassFlagSoftReference);
719 class_root = FindSystemClass(self, "Ljava/lang/ref/WeakReference;");
720 CHECK_EQ(class_root->GetClassFlags(), mirror::kClassFlagNormal);
721 class_root->SetClassFlags(class_root->GetClassFlags() | mirror::kClassFlagWeakReference);
723 // Setup the ClassLoader, verifying the object_size_.
724 class_root = FindSystemClass(self, "Ljava/lang/ClassLoader;");
725 class_root->SetClassLoaderClass();
726 CHECK_EQ(class_root->GetObjectSize(), mirror::ClassLoader::InstanceSize());
727 SetClassRoot(kJavaLangClassLoader, class_root);
729 // Set up java.lang.Throwable, java.lang.ClassNotFoundException, and
730 // java.lang.StackTraceElement as a convenience.
731 SetClassRoot(kJavaLangThrowable, FindSystemClass(self, "Ljava/lang/Throwable;"));
732 mirror::Throwable::SetClass(GetClassRoot(kJavaLangThrowable));
733 SetClassRoot(kJavaLangClassNotFoundException,
734 FindSystemClass(self, "Ljava/lang/ClassNotFoundException;"));
735 SetClassRoot(kJavaLangStackTraceElement, FindSystemClass(self, "Ljava/lang/StackTraceElement;"));
736 SetClassRoot(kJavaLangStackTraceElementArrayClass,
737 FindSystemClass(self, "[Ljava/lang/StackTraceElement;"));
738 mirror::StackTraceElement::SetClass(GetClassRoot(kJavaLangStackTraceElement));
740 // Ensure void type is resolved in the core's dex cache so java.lang.Void is correctly
743 const DexFile& dex_file = java_lang_Object->GetDexFile();
744 const DexFile::TypeId* void_type_id = dex_file.FindTypeId("V");
745 CHECK(void_type_id != nullptr);
746 dex::TypeIndex void_type_idx = dex_file.GetIndexForTypeId(*void_type_id);
747 // Now we resolve void type so the dex cache contains it. We use java.lang.Object class
748 // as referrer so the used dex cache is core's one.
749 ObjPtr<mirror::Class> resolved_type = ResolveType(dex_file,
751 java_lang_Object.Get());
752 CHECK_EQ(resolved_type, GetClassRoot(kPrimitiveVoid));
753 self->AssertNoPendingException();
756 // Create conflict tables that depend on the class linker.
757 runtime->FixupConflictTables();
761 VLOG(startup) << "ClassLinker::InitFromCompiler exiting";
766 void ClassLinker::FinishInit(Thread* self) {
767 VLOG(startup) << "ClassLinker::FinishInit entering";
769 // Let the heap know some key offsets into java.lang.ref instances
770 // Note: we hard code the field indexes here rather than using FindInstanceField
771 // as the types of the field can't be resolved prior to the runtime being
773 StackHandleScope<2> hs(self);
774 Handle<mirror::Class> java_lang_ref_Reference = hs.NewHandle(GetClassRoot(kJavaLangRefReference));
775 Handle<mirror::Class> java_lang_ref_FinalizerReference =
776 hs.NewHandle(FindSystemClass(self, "Ljava/lang/ref/FinalizerReference;"));
778 ArtField* pendingNext = java_lang_ref_Reference->GetInstanceField(0);
779 CHECK_STREQ(pendingNext->GetName(), "pendingNext");
780 CHECK_STREQ(pendingNext->GetTypeDescriptor(), "Ljava/lang/ref/Reference;");
782 ArtField* queue = java_lang_ref_Reference->GetInstanceField(1);
783 CHECK_STREQ(queue->GetName(), "queue");
784 CHECK_STREQ(queue->GetTypeDescriptor(), "Ljava/lang/ref/ReferenceQueue;");
786 ArtField* queueNext = java_lang_ref_Reference->GetInstanceField(2);
787 CHECK_STREQ(queueNext->GetName(), "queueNext");
788 CHECK_STREQ(queueNext->GetTypeDescriptor(), "Ljava/lang/ref/Reference;");
790 ArtField* referent = java_lang_ref_Reference->GetInstanceField(3);
791 CHECK_STREQ(referent->GetName(), "referent");
792 CHECK_STREQ(referent->GetTypeDescriptor(), "Ljava/lang/Object;");
794 ArtField* zombie = java_lang_ref_FinalizerReference->GetInstanceField(2);
795 CHECK_STREQ(zombie->GetName(), "zombie");
796 CHECK_STREQ(zombie->GetTypeDescriptor(), "Ljava/lang/Object;");
798 // ensure all class_roots_ are initialized
799 for (size_t i = 0; i < kClassRootsMax; i++) {
800 ClassRoot class_root = static_cast<ClassRoot>(i);
801 ObjPtr<mirror::Class> klass = GetClassRoot(class_root);
802 CHECK(klass != nullptr);
803 DCHECK(klass->IsArrayClass() || klass->IsPrimitive() || klass->GetDexCache() != nullptr);
804 // note SetClassRoot does additional validation.
805 // if possible add new checks there to catch errors early
808 CHECK(!array_iftable_.IsNull());
810 // disable the slow paths in FindClass and CreatePrimitiveClass now
811 // that Object, Class, and Object[] are setup
814 VLOG(startup) << "ClassLinker::FinishInit exiting";
817 void ClassLinker::RunRootClinits() {
818 Thread* self = Thread::Current();
819 for (size_t i = 0; i < ClassLinker::kClassRootsMax; ++i) {
820 ObjPtr<mirror::Class> c = GetClassRoot(ClassRoot(i));
821 if (!c->IsArrayClass() && !c->IsPrimitive()) {
822 StackHandleScope<1> hs(self);
823 Handle<mirror::Class> h_class(hs.NewHandle(GetClassRoot(ClassRoot(i))));
824 EnsureInitialized(self, h_class, true, true);
825 self->AssertNoPendingException();
830 // Set image methods' entry point to interpreter.
831 class SetInterpreterEntrypointArtMethodVisitor : public ArtMethodVisitor {
833 explicit SetInterpreterEntrypointArtMethodVisitor(PointerSize image_pointer_size)
834 : image_pointer_size_(image_pointer_size) {}
836 void Visit(ArtMethod* method) OVERRIDE REQUIRES_SHARED(Locks::mutator_lock_) {
837 if (kIsDebugBuild && !method->IsRuntimeMethod()) {
838 CHECK(method->GetDeclaringClass() != nullptr);
840 if (!method->IsNative() && !method->IsRuntimeMethod() && !method->IsResolutionMethod()) {
841 method->SetEntryPointFromQuickCompiledCodePtrSize(GetQuickToInterpreterBridge(),
842 image_pointer_size_);
847 const PointerSize image_pointer_size_;
849 DISALLOW_COPY_AND_ASSIGN(SetInterpreterEntrypointArtMethodVisitor);
852 struct TrampolineCheckData {
853 const void* quick_resolution_trampoline;
854 const void* quick_imt_conflict_trampoline;
855 const void* quick_generic_jni_trampoline;
856 const void* quick_to_interpreter_bridge_trampoline;
857 PointerSize pointer_size;
862 static void CheckTrampolines(mirror::Object* obj, void* arg) NO_THREAD_SAFETY_ANALYSIS {
863 if (obj->IsClass()) {
864 ObjPtr<mirror::Class> klass = obj->AsClass();
865 TrampolineCheckData* d = reinterpret_cast<TrampolineCheckData*>(arg);
866 for (ArtMethod& m : klass->GetMethods(d->pointer_size)) {
867 const void* entrypoint = m.GetEntryPointFromQuickCompiledCodePtrSize(d->pointer_size);
868 if (entrypoint == d->quick_resolution_trampoline ||
869 entrypoint == d->quick_imt_conflict_trampoline ||
870 entrypoint == d->quick_generic_jni_trampoline ||
871 entrypoint == d->quick_to_interpreter_bridge_trampoline) {
880 bool ClassLinker::InitFromBootImage(std::string* error_msg) {
881 VLOG(startup) << __FUNCTION__ << " entering";
884 Runtime* const runtime = Runtime::Current();
885 Thread* const self = Thread::Current();
886 gc::Heap* const heap = runtime->GetHeap();
887 std::vector<gc::space::ImageSpace*> spaces = heap->GetBootImageSpaces();
888 CHECK(!spaces.empty());
889 uint32_t pointer_size_unchecked = spaces[0]->GetImageHeader().GetPointerSizeUnchecked();
890 if (!ValidPointerSize(pointer_size_unchecked)) {
891 *error_msg = StringPrintf("Invalid image pointer size: %u", pointer_size_unchecked);
894 image_pointer_size_ = spaces[0]->GetImageHeader().GetPointerSize();
895 if (!runtime->IsAotCompiler()) {
896 // Only the Aot compiler supports having an image with a different pointer size than the
897 // runtime. This happens on the host for compiling 32 bit tests since we use a 64 bit libart
898 // compiler. We may also use 32 bit dex2oat on a system with 64 bit apps.
899 if (image_pointer_size_ != kRuntimePointerSize) {
900 *error_msg = StringPrintf("Runtime must use current image pointer size: %zu vs %zu",
901 static_cast<size_t>(image_pointer_size_),
906 std::vector<const OatFile*> oat_files =
907 runtime->GetOatFileManager().RegisterImageOatFiles(spaces);
908 DCHECK(!oat_files.empty());
909 const OatHeader& default_oat_header = oat_files[0]->GetOatHeader();
910 CHECK_EQ(default_oat_header.GetImageFileLocationOatChecksum(), 0U);
911 CHECK_EQ(default_oat_header.GetImageFileLocationOatDataBegin(), 0U);
912 const char* image_file_location = oat_files[0]->GetOatHeader().
913 GetStoreValueByKey(OatHeader::kImageLocationKey);
914 CHECK(image_file_location == nullptr || *image_file_location == 0);
915 quick_resolution_trampoline_ = default_oat_header.GetQuickResolutionTrampoline();
916 quick_imt_conflict_trampoline_ = default_oat_header.GetQuickImtConflictTrampoline();
917 quick_generic_jni_trampoline_ = default_oat_header.GetQuickGenericJniTrampoline();
918 quick_to_interpreter_bridge_trampoline_ = default_oat_header.GetQuickToInterpreterBridge();
920 // Check that the other images use the same trampoline.
921 for (size_t i = 1; i < oat_files.size(); ++i) {
922 const OatHeader& ith_oat_header = oat_files[i]->GetOatHeader();
923 const void* ith_quick_resolution_trampoline =
924 ith_oat_header.GetQuickResolutionTrampoline();
925 const void* ith_quick_imt_conflict_trampoline =
926 ith_oat_header.GetQuickImtConflictTrampoline();
927 const void* ith_quick_generic_jni_trampoline =
928 ith_oat_header.GetQuickGenericJniTrampoline();
929 const void* ith_quick_to_interpreter_bridge_trampoline =
930 ith_oat_header.GetQuickToInterpreterBridge();
931 if (ith_quick_resolution_trampoline != quick_resolution_trampoline_ ||
932 ith_quick_imt_conflict_trampoline != quick_imt_conflict_trampoline_ ||
933 ith_quick_generic_jni_trampoline != quick_generic_jni_trampoline_ ||
934 ith_quick_to_interpreter_bridge_trampoline != quick_to_interpreter_bridge_trampoline_) {
935 // Make sure that all methods in this image do not contain those trampolines as
936 // entrypoints. Otherwise the class-linker won't be able to work with a single set.
937 TrampolineCheckData data;
939 data.pointer_size = GetImagePointerSize();
940 data.quick_resolution_trampoline = ith_quick_resolution_trampoline;
941 data.quick_imt_conflict_trampoline = ith_quick_imt_conflict_trampoline;
942 data.quick_generic_jni_trampoline = ith_quick_generic_jni_trampoline;
943 data.quick_to_interpreter_bridge_trampoline = ith_quick_to_interpreter_bridge_trampoline;
944 ReaderMutexLock mu(self, *Locks::heap_bitmap_lock_);
945 spaces[i]->GetLiveBitmap()->Walk(CheckTrampolines, &data);
947 ArtMethod* m = data.m;
948 LOG(ERROR) << "Found a broken ArtMethod: " << ArtMethod::PrettyMethod(m);
949 *error_msg = "Found an ArtMethod with a bad entrypoint";
956 class_roots_ = GcRoot<mirror::ObjectArray<mirror::Class>>(
957 down_cast<mirror::ObjectArray<mirror::Class>*>(
958 spaces[0]->GetImageHeader().GetImageRoot(ImageHeader::kClassRoots)));
959 mirror::Class::SetClassClass(class_roots_.Read()->Get(kJavaLangClass));
961 // Special case of setting up the String class early so that we can test arbitrary objects
962 // as being Strings or not
963 mirror::String::SetClass(GetClassRoot(kJavaLangString));
965 ObjPtr<mirror::Class> java_lang_Object = GetClassRoot(kJavaLangObject);
966 java_lang_Object->SetObjectSize(sizeof(mirror::Object));
967 // Allocate in non-movable so that it's possible to check if a JNI weak global ref has been
968 // cleared without triggering the read barrier and unintentionally mark the sentinel alive.
969 runtime->SetSentinel(heap->AllocNonMovableObject<true>(
970 self, java_lang_Object, java_lang_Object->GetObjectSize(), VoidFunctor()));
972 // reinit array_iftable_ from any array class instance, they should be ==
973 array_iftable_ = GcRoot<mirror::IfTable>(GetClassRoot(kObjectArrayClass)->GetIfTable());
974 DCHECK_EQ(array_iftable_.Read(), GetClassRoot(kBooleanArrayClass)->GetIfTable());
975 // String class root was set above
976 mirror::Field::SetClass(GetClassRoot(kJavaLangReflectField));
977 mirror::Field::SetArrayClass(GetClassRoot(kJavaLangReflectFieldArrayClass));
978 mirror::Constructor::SetClass(GetClassRoot(kJavaLangReflectConstructor));
979 mirror::Constructor::SetArrayClass(GetClassRoot(kJavaLangReflectConstructorArrayClass));
980 mirror::Method::SetClass(GetClassRoot(kJavaLangReflectMethod));
981 mirror::Method::SetArrayClass(GetClassRoot(kJavaLangReflectMethodArrayClass));
982 mirror::MethodType::SetClass(GetClassRoot(kJavaLangInvokeMethodType));
983 mirror::MethodHandleImpl::SetClass(GetClassRoot(kJavaLangInvokeMethodHandleImpl));
984 mirror::Reference::SetClass(GetClassRoot(kJavaLangRefReference));
985 mirror::BooleanArray::SetArrayClass(GetClassRoot(kBooleanArrayClass));
986 mirror::ByteArray::SetArrayClass(GetClassRoot(kByteArrayClass));
987 mirror::CharArray::SetArrayClass(GetClassRoot(kCharArrayClass));
988 mirror::DoubleArray::SetArrayClass(GetClassRoot(kDoubleArrayClass));
989 mirror::FloatArray::SetArrayClass(GetClassRoot(kFloatArrayClass));
990 mirror::IntArray::SetArrayClass(GetClassRoot(kIntArrayClass));
991 mirror::LongArray::SetArrayClass(GetClassRoot(kLongArrayClass));
992 mirror::ShortArray::SetArrayClass(GetClassRoot(kShortArrayClass));
993 mirror::Throwable::SetClass(GetClassRoot(kJavaLangThrowable));
994 mirror::StackTraceElement::SetClass(GetClassRoot(kJavaLangStackTraceElement));
995 mirror::EmulatedStackFrame::SetClass(GetClassRoot(kDalvikSystemEmulatedStackFrame));
996 mirror::ClassExt::SetClass(GetClassRoot(kDalvikSystemClassExt));
998 for (gc::space::ImageSpace* image_space : spaces) {
999 // Boot class loader, use a null handle.
1000 std::vector<std::unique_ptr<const DexFile>> dex_files;
1001 if (!AddImageSpace(image_space,
1002 ScopedNullHandle<mirror::ClassLoader>(),
1003 /*dex_elements*/nullptr,
1004 /*dex_location*/nullptr,
1009 // Append opened dex files at the end.
1010 boot_dex_files_.insert(boot_dex_files_.end(),
1011 std::make_move_iterator(dex_files.begin()),
1012 std::make_move_iterator(dex_files.end()));
1016 VLOG(startup) << __FUNCTION__ << " exiting";
1020 bool ClassLinker::IsBootClassLoader(ScopedObjectAccessAlreadyRunnable& soa,
1021 ObjPtr<mirror::ClassLoader> class_loader) {
1022 return class_loader == nullptr ||
1023 soa.Decode<mirror::Class>(WellKnownClasses::java_lang_BootClassLoader) ==
1024 class_loader->GetClass();
1027 static mirror::String* GetDexPathListElementName(ObjPtr<mirror::Object> element)
1028 REQUIRES_SHARED(Locks::mutator_lock_) {
1029 ArtField* const dex_file_field =
1030 jni::DecodeArtField(WellKnownClasses::dalvik_system_DexPathList__Element_dexFile);
1031 ArtField* const dex_file_name_field =
1032 jni::DecodeArtField(WellKnownClasses::dalvik_system_DexFile_fileName);
1033 DCHECK(dex_file_field != nullptr);
1034 DCHECK(dex_file_name_field != nullptr);
1035 DCHECK(element != nullptr);
1036 CHECK_EQ(dex_file_field->GetDeclaringClass(), element->GetClass()) << element->PrettyTypeOf();
1037 ObjPtr<mirror::Object> dex_file = dex_file_field->GetObject(element);
1038 if (dex_file == nullptr) {
1041 ObjPtr<mirror::Object> name_object = dex_file_name_field->GetObject(dex_file);
1042 if (name_object != nullptr) {
1043 return name_object->AsString();
1048 static bool FlattenPathClassLoader(ObjPtr<mirror::ClassLoader> class_loader,
1049 std::list<mirror::String*>* out_dex_file_names,
1050 std::string* error_msg)
1051 REQUIRES_SHARED(Locks::mutator_lock_) {
1052 DCHECK(out_dex_file_names != nullptr);
1053 DCHECK(error_msg != nullptr);
1054 ScopedObjectAccessUnchecked soa(Thread::Current());
1055 ArtField* const dex_path_list_field =
1056 jni::DecodeArtField(WellKnownClasses::dalvik_system_BaseDexClassLoader_pathList);
1057 ArtField* const dex_elements_field =
1058 jni::DecodeArtField(WellKnownClasses::dalvik_system_DexPathList_dexElements);
1059 CHECK(dex_path_list_field != nullptr);
1060 CHECK(dex_elements_field != nullptr);
1061 while (!ClassLinker::IsBootClassLoader(soa, class_loader)) {
1062 if (soa.Decode<mirror::Class>(WellKnownClasses::dalvik_system_PathClassLoader) !=
1063 class_loader->GetClass()) {
1064 *error_msg = StringPrintf("Unknown class loader type %s",
1065 class_loader->PrettyTypeOf().c_str());
1066 // Unsupported class loader.
1069 ObjPtr<mirror::Object> dex_path_list = dex_path_list_field->GetObject(class_loader);
1070 if (dex_path_list != nullptr) {
1071 // DexPathList has an array dexElements of Elements[] which each contain a dex file.
1072 ObjPtr<mirror::Object> dex_elements_obj = dex_elements_field->GetObject(dex_path_list);
1073 // Loop through each dalvik.system.DexPathList$Element's dalvik.system.DexFile and look
1074 // at the mCookie which is a DexFile vector.
1075 if (dex_elements_obj != nullptr) {
1076 ObjPtr<mirror::ObjectArray<mirror::Object>> dex_elements =
1077 dex_elements_obj->AsObjectArray<mirror::Object>();
1078 // Reverse order since we insert the parent at the front.
1079 for (int32_t i = dex_elements->GetLength() - 1; i >= 0; --i) {
1080 ObjPtr<mirror::Object> element = dex_elements->GetWithoutChecks(i);
1081 if (element == nullptr) {
1082 *error_msg = StringPrintf("Null dex element at index %d", i);
1085 ObjPtr<mirror::String> const name = GetDexPathListElementName(element);
1086 if (name == nullptr) {
1087 *error_msg = StringPrintf("Null name for dex element at index %d", i);
1090 out_dex_file_names->push_front(name.Ptr());
1094 class_loader = class_loader->GetParent();
1099 class FixupArtMethodArrayVisitor : public ArtMethodVisitor {
1101 explicit FixupArtMethodArrayVisitor(const ImageHeader& header) : header_(header) {}
1103 virtual void Visit(ArtMethod* method) REQUIRES_SHARED(Locks::mutator_lock_) {
1104 const bool is_copied = method->IsCopied();
1105 ArtMethod** resolved_methods = method->GetDexCacheResolvedMethods(kRuntimePointerSize);
1106 if (resolved_methods != nullptr) {
1107 bool in_image_space = false;
1108 if (kIsDebugBuild || is_copied) {
1109 in_image_space = header_.GetImageSection(ImageHeader::kSectionDexCacheArrays).Contains(
1110 reinterpret_cast<const uint8_t*>(resolved_methods) - header_.GetImageBegin());
1112 // Must be in image space for non-miranda method.
1113 DCHECK(is_copied || in_image_space)
1114 << resolved_methods << " is not in image starting at "
1115 << reinterpret_cast<void*>(header_.GetImageBegin());
1116 if (!is_copied || in_image_space) {
1117 method->SetDexCacheResolvedMethods(method->GetDexCache()->GetResolvedMethods(),
1118 kRuntimePointerSize);
1124 const ImageHeader& header_;
1127 class VerifyClassInTableArtMethodVisitor : public ArtMethodVisitor {
1129 explicit VerifyClassInTableArtMethodVisitor(ClassTable* table) : table_(table) {}
1131 virtual void Visit(ArtMethod* method)
1132 REQUIRES_SHARED(Locks::mutator_lock_, Locks::classlinker_classes_lock_) {
1133 ObjPtr<mirror::Class> klass = method->GetDeclaringClass();
1134 if (klass != nullptr && !Runtime::Current()->GetHeap()->ObjectIsInBootImageSpace(klass)) {
1135 CHECK_EQ(table_->LookupByDescriptor(klass), klass) << mirror::Class::PrettyClass(klass);
1140 ClassTable* const table_;
1143 class VerifyDeclaringClassVisitor : public ArtMethodVisitor {
1145 VerifyDeclaringClassVisitor() REQUIRES_SHARED(Locks::mutator_lock_, Locks::heap_bitmap_lock_)
1146 : live_bitmap_(Runtime::Current()->GetHeap()->GetLiveBitmap()) {}
1148 virtual void Visit(ArtMethod* method)
1149 REQUIRES_SHARED(Locks::mutator_lock_, Locks::heap_bitmap_lock_) {
1150 ObjPtr<mirror::Class> klass = method->GetDeclaringClassUnchecked();
1151 if (klass != nullptr) {
1152 CHECK(live_bitmap_->Test(klass.Ptr())) << "Image method has unmarked declaring class";
1157 gc::accounting::HeapBitmap* const live_bitmap_;
1160 // Copies data from one array to another array at the same position
1161 // if pred returns false. If there is a page of continuous data in
1162 // the src array for which pred consistently returns true then
1163 // corresponding page in the dst array will not be touched.
1164 // This should reduce number of allocated physical pages.
1165 template <class T, class NullPred>
1166 static void CopyNonNull(const T* src, size_t count, T* dst, const NullPred& pred) {
1167 for (size_t i = 0; i < count; ++i) {
1168 if (!pred(src[i])) {
1174 bool ClassLinker::UpdateAppImageClassLoadersAndDexCaches(
1175 gc::space::ImageSpace* space,
1176 Handle<mirror::ClassLoader> class_loader,
1177 Handle<mirror::ObjectArray<mirror::DexCache>> dex_caches,
1178 ClassTable::ClassSet* new_class_set,
1179 bool* out_forward_dex_cache_array,
1180 std::string* out_error_msg) {
1181 DCHECK(out_forward_dex_cache_array != nullptr);
1182 DCHECK(out_error_msg != nullptr);
1183 Thread* const self = Thread::Current();
1184 gc::Heap* const heap = Runtime::Current()->GetHeap();
1185 const ImageHeader& header = space->GetImageHeader();
1187 // Add image classes into the class table for the class loader, and fixup the dex caches and
1188 // class loader fields.
1189 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_);
1190 // Dex cache array fixup is all or nothing, we must reject app images that have mixed since we
1191 // rely on clobering the dex cache arrays in the image to forward to bss.
1192 size_t num_dex_caches_with_bss_arrays = 0;
1193 const size_t num_dex_caches = dex_caches->GetLength();
1194 for (size_t i = 0; i < num_dex_caches; i++) {
1195 ObjPtr<mirror::DexCache> const dex_cache = dex_caches->Get(i);
1196 const DexFile* const dex_file = dex_cache->GetDexFile();
1197 const OatFile::OatDexFile* oat_dex_file = dex_file->GetOatDexFile();
1198 if (oat_dex_file != nullptr && oat_dex_file->GetDexCacheArrays() != nullptr) {
1199 ++num_dex_caches_with_bss_arrays;
1202 *out_forward_dex_cache_array = num_dex_caches_with_bss_arrays != 0;
1203 if (*out_forward_dex_cache_array) {
1204 if (num_dex_caches_with_bss_arrays != num_dex_caches) {
1205 // Reject application image since we cannot forward only some of the dex cache arrays.
1206 // TODO: We could get around this by having a dedicated forwarding slot. It should be an
1208 *out_error_msg = StringPrintf("Dex caches in bss does not match total: %zu vs %zu",
1209 num_dex_caches_with_bss_arrays,
1214 // Only add the classes to the class loader after the points where we can return false.
1215 for (size_t i = 0; i < num_dex_caches; i++) {
1216 ObjPtr<mirror::DexCache> dex_cache = dex_caches->Get(i);
1217 const DexFile* const dex_file = dex_cache->GetDexFile();
1218 const OatFile::OatDexFile* oat_dex_file = dex_file->GetOatDexFile();
1219 if (oat_dex_file != nullptr && oat_dex_file->GetDexCacheArrays() != nullptr) {
1220 // If the oat file expects the dex cache arrays to be in the BSS, then allocate there and
1221 // copy over the arrays.
1222 DCHECK(dex_file != nullptr);
1223 size_t num_strings = mirror::DexCache::kDexCacheStringCacheSize;
1224 if (dex_file->NumStringIds() < num_strings) {
1225 num_strings = dex_file->NumStringIds();
1227 const size_t num_types = dex_file->NumTypeIds();
1228 const size_t num_methods = dex_file->NumMethodIds();
1229 const size_t num_fields = dex_file->NumFieldIds();
1230 size_t num_method_types = mirror::DexCache::kDexCacheMethodTypeCacheSize;
1231 if (dex_file->NumProtoIds() < num_method_types) {
1232 num_method_types = dex_file->NumProtoIds();
1235 CHECK_EQ(num_strings, dex_cache->NumStrings());
1236 CHECK_EQ(num_types, dex_cache->NumResolvedTypes());
1237 CHECK_EQ(num_methods, dex_cache->NumResolvedMethods());
1238 CHECK_EQ(num_fields, dex_cache->NumResolvedFields());
1239 CHECK_EQ(num_method_types, dex_cache->NumResolvedMethodTypes());
1240 DexCacheArraysLayout layout(image_pointer_size_, dex_file);
1241 uint8_t* const raw_arrays = oat_dex_file->GetDexCacheArrays();
1242 if (num_strings != 0u) {
1243 mirror::StringDexCacheType* const image_resolved_strings = dex_cache->GetStrings();
1244 mirror::StringDexCacheType* const strings =
1245 reinterpret_cast<mirror::StringDexCacheType*>(raw_arrays + layout.StringsOffset());
1246 for (size_t j = 0; j < num_strings; ++j) {
1247 DCHECK_EQ(strings[j].load(std::memory_order_relaxed).index, 0u);
1248 DCHECK(strings[j].load(std::memory_order_relaxed).object.IsNull());
1249 strings[j].store(image_resolved_strings[j].load(std::memory_order_relaxed),
1250 std::memory_order_relaxed);
1252 mirror::StringDexCachePair::Initialize(strings);
1253 dex_cache->SetStrings(strings);
1255 if (num_types != 0u) {
1256 GcRoot<mirror::Class>* const image_resolved_types = dex_cache->GetResolvedTypes();
1257 GcRoot<mirror::Class>* const types =
1258 reinterpret_cast<GcRoot<mirror::Class>*>(raw_arrays + layout.TypesOffset());
1259 for (size_t j = 0; kIsDebugBuild && j < num_types; ++j) {
1260 DCHECK(types[j].IsNull());
1262 CopyNonNull(image_resolved_types,
1265 [](const GcRoot<mirror::Class>& elem) {
1266 return elem.IsNull();
1268 dex_cache->SetResolvedTypes(types);
1270 if (num_methods != 0u) {
1271 ArtMethod** const methods = reinterpret_cast<ArtMethod**>(
1272 raw_arrays + layout.MethodsOffset());
1273 ArtMethod** const image_resolved_methods = dex_cache->GetResolvedMethods();
1274 for (size_t j = 0; kIsDebugBuild && j < num_methods; ++j) {
1275 DCHECK(methods[j] == nullptr);
1277 CopyNonNull(image_resolved_methods,
1280 [] (const ArtMethod* method) {
1281 return method == nullptr;
1283 dex_cache->SetResolvedMethods(methods);
1285 if (num_fields != 0u) {
1286 ArtField** const fields =
1287 reinterpret_cast<ArtField**>(raw_arrays + layout.FieldsOffset());
1288 for (size_t j = 0; kIsDebugBuild && j < num_fields; ++j) {
1289 DCHECK(fields[j] == nullptr);
1291 CopyNonNull(dex_cache->GetResolvedFields(),
1294 [] (const ArtField* field) {
1295 return field == nullptr;
1297 dex_cache->SetResolvedFields(fields);
1299 if (num_method_types != 0u) {
1300 // NOTE: We currently (Sep 2016) do not resolve any method types at
1301 // compile time, but plan to in the future. This code exists for the
1302 // sake of completeness.
1303 mirror::MethodTypeDexCacheType* const image_resolved_method_types =
1304 dex_cache->GetResolvedMethodTypes();
1305 mirror::MethodTypeDexCacheType* const method_types =
1306 reinterpret_cast<mirror::MethodTypeDexCacheType*>(
1307 raw_arrays + layout.MethodTypesOffset());
1308 for (size_t j = 0; j < num_method_types; ++j) {
1309 DCHECK_EQ(method_types[j].load(std::memory_order_relaxed).index, 0u);
1310 DCHECK(method_types[j].load(std::memory_order_relaxed).object.IsNull());
1311 method_types[j].store(
1312 image_resolved_method_types[j].load(std::memory_order_relaxed),
1313 std::memory_order_relaxed);
1316 mirror::MethodTypeDexCachePair::Initialize(method_types);
1317 dex_cache->SetResolvedMethodTypes(method_types);
1321 WriterMutexLock mu2(self, *Locks::dex_lock_);
1322 // Make sure to do this after we update the arrays since we store the resolved types array
1323 // in DexCacheData in RegisterDexFileLocked. We need the array pointer to be the one in the
1325 ObjPtr<mirror::DexCache> existing_dex_cache = FindDexCacheLocked(self,
1327 /*allow_failure*/true);
1328 CHECK(existing_dex_cache == nullptr);
1329 StackHandleScope<1> hs3(self);
1330 Handle<mirror::DexCache> h_dex_cache = hs3.NewHandle(dex_cache);
1331 RegisterDexFileLocked(*dex_file, h_dex_cache);
1332 if (kIsDebugBuild) {
1333 dex_cache.Assign(h_dex_cache.Get()); // Update dex_cache, used below in debug build.
1336 if (kIsDebugBuild) {
1337 CHECK(new_class_set != nullptr);
1338 GcRoot<mirror::Class>* const types = dex_cache->GetResolvedTypes();
1339 const size_t num_types = dex_cache->NumResolvedTypes();
1340 for (int32_t j = 0; j < static_cast<int32_t>(num_types); j++) {
1341 // The image space is not yet added to the heap, avoid read barriers.
1342 ObjPtr<mirror::Class> klass = types[j].Read();
1343 if (space->HasAddress(klass.Ptr())) {
1344 DCHECK(!klass->IsErroneous()) << klass->GetStatus();
1345 auto it = new_class_set->Find(ClassTable::TableSlot(klass));
1346 DCHECK(it != new_class_set->end());
1347 DCHECK_EQ(it->Read(), klass);
1348 ObjPtr<mirror::Class> super_class = klass->GetSuperClass();
1349 if (super_class != nullptr && !heap->ObjectIsInBootImageSpace(super_class)) {
1350 auto it2 = new_class_set->Find(ClassTable::TableSlot(super_class));
1351 DCHECK(it2 != new_class_set->end());
1352 DCHECK_EQ(it2->Read(), super_class);
1354 for (ArtMethod& m : klass->GetDirectMethods(kRuntimePointerSize)) {
1355 const void* code = m.GetEntryPointFromQuickCompiledCode();
1356 const void* oat_code = m.IsInvokable() ? GetQuickOatCodeFor(&m) : code;
1357 if (!IsQuickResolutionStub(code) &&
1358 !IsQuickGenericJniStub(code) &&
1359 !IsQuickToInterpreterBridge(code) &&
1361 DCHECK_EQ(code, oat_code) << m.PrettyMethod();
1364 for (ArtMethod& m : klass->GetVirtualMethods(kRuntimePointerSize)) {
1365 const void* code = m.GetEntryPointFromQuickCompiledCode();
1366 const void* oat_code = m.IsInvokable() ? GetQuickOatCodeFor(&m) : code;
1367 if (!IsQuickResolutionStub(code) &&
1368 !IsQuickGenericJniStub(code) &&
1369 !IsQuickToInterpreterBridge(code) &&
1371 DCHECK_EQ(code, oat_code) << m.PrettyMethod();
1379 if (*out_forward_dex_cache_array) {
1380 ScopedTrace timing("Fixup ArtMethod dex cache arrays");
1381 FixupArtMethodArrayVisitor visitor(header);
1382 header.VisitPackedArtMethods(&visitor, space->Begin(), kRuntimePointerSize);
1383 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(class_loader.Get());
1385 if (kVerifyArtMethodDeclaringClasses) {
1386 ScopedTrace timing("Verify declaring classes");
1387 ReaderMutexLock rmu(self, *Locks::heap_bitmap_lock_);
1388 VerifyDeclaringClassVisitor visitor;
1389 header.VisitPackedArtMethods(&visitor, space->Begin(), kRuntimePointerSize);
1394 // Update the class loader. Should only be used on classes in the image space.
1395 class UpdateClassLoaderVisitor {
1397 UpdateClassLoaderVisitor(gc::space::ImageSpace* space, ObjPtr<mirror::ClassLoader> class_loader)
1399 class_loader_(class_loader) {}
1401 bool operator()(ObjPtr<mirror::Class> klass) const REQUIRES_SHARED(Locks::mutator_lock_) {
1402 // Do not update class loader for boot image classes where the app image
1403 // class loader is only the initiating loader but not the defining loader.
1404 if (klass->GetClassLoader() != nullptr) {
1405 klass->SetClassLoader(class_loader_);
1410 gc::space::ImageSpace* const space_;
1411 ObjPtr<mirror::ClassLoader> const class_loader_;
1414 static std::unique_ptr<const DexFile> OpenOatDexFile(const OatFile* oat_file,
1415 const char* location,
1416 std::string* error_msg)
1417 REQUIRES_SHARED(Locks::mutator_lock_) {
1418 DCHECK(error_msg != nullptr);
1419 std::unique_ptr<const DexFile> dex_file;
1420 const OatFile::OatDexFile* oat_dex_file = oat_file->GetOatDexFile(location, nullptr, error_msg);
1421 if (oat_dex_file == nullptr) {
1422 return std::unique_ptr<const DexFile>();
1424 std::string inner_error_msg;
1425 dex_file = oat_dex_file->OpenDexFile(&inner_error_msg);
1426 if (dex_file == nullptr) {
1427 *error_msg = StringPrintf("Failed to open dex file %s from within oat file %s error '%s'",
1429 oat_file->GetLocation().c_str(),
1430 inner_error_msg.c_str());
1431 return std::unique_ptr<const DexFile>();
1434 if (dex_file->GetLocationChecksum() != oat_dex_file->GetDexFileLocationChecksum()) {
1435 *error_msg = StringPrintf("Checksums do not match for %s: %x vs %x",
1437 dex_file->GetLocationChecksum(),
1438 oat_dex_file->GetDexFileLocationChecksum());
1439 return std::unique_ptr<const DexFile>();
1444 bool ClassLinker::OpenImageDexFiles(gc::space::ImageSpace* space,
1445 std::vector<std::unique_ptr<const DexFile>>* out_dex_files,
1446 std::string* error_msg) {
1447 ScopedAssertNoThreadSuspension nts(__FUNCTION__);
1448 const ImageHeader& header = space->GetImageHeader();
1449 ObjPtr<mirror::Object> dex_caches_object = header.GetImageRoot(ImageHeader::kDexCaches);
1450 DCHECK(dex_caches_object != nullptr);
1451 mirror::ObjectArray<mirror::DexCache>* dex_caches =
1452 dex_caches_object->AsObjectArray<mirror::DexCache>();
1453 const OatFile* oat_file = space->GetOatFile();
1454 for (int32_t i = 0; i < dex_caches->GetLength(); i++) {
1455 ObjPtr<mirror::DexCache> dex_cache = dex_caches->Get(i);
1456 std::string dex_file_location(dex_cache->GetLocation()->ToModifiedUtf8());
1457 std::unique_ptr<const DexFile> dex_file = OpenOatDexFile(oat_file,
1458 dex_file_location.c_str(),
1460 if (dex_file == nullptr) {
1463 dex_cache->SetDexFile(dex_file.get());
1464 out_dex_files->push_back(std::move(dex_file));
1469 // Helper class for ArtMethod checks when adding an image. Keeps all required functionality
1470 // together and caches some intermediate results.
1471 class ImageSanityChecks FINAL {
1473 static void CheckObjects(gc::Heap* heap, ClassLinker* class_linker)
1474 REQUIRES_SHARED(Locks::mutator_lock_) {
1475 ImageSanityChecks isc(heap, class_linker);
1476 heap->VisitObjects(ImageSanityChecks::SanityCheckObjectsCallback, &isc);
1479 static void CheckPointerArray(gc::Heap* heap,
1480 ClassLinker* class_linker,
1483 REQUIRES_SHARED(Locks::mutator_lock_) {
1484 ImageSanityChecks isc(heap, class_linker);
1485 isc.SanityCheckArtMethodPointerArray(arr, size);
1488 static void SanityCheckObjectsCallback(mirror::Object* obj, void* arg)
1489 REQUIRES_SHARED(Locks::mutator_lock_) {
1490 DCHECK(obj != nullptr);
1491 CHECK(obj->GetClass() != nullptr) << "Null class in object " << obj;
1492 CHECK(obj->GetClass()->GetClass() != nullptr) << "Null class class " << obj;
1493 if (obj->IsClass()) {
1494 ImageSanityChecks* isc = reinterpret_cast<ImageSanityChecks*>(arg);
1496 auto klass = obj->AsClass();
1497 for (ArtField& field : klass->GetIFields()) {
1498 CHECK_EQ(field.GetDeclaringClass(), klass);
1500 for (ArtField& field : klass->GetSFields()) {
1501 CHECK_EQ(field.GetDeclaringClass(), klass);
1503 const auto pointer_size = isc->pointer_size_;
1504 for (auto& m : klass->GetMethods(pointer_size)) {
1505 isc->SanityCheckArtMethod(&m, klass);
1507 auto* vtable = klass->GetVTable();
1508 if (vtable != nullptr) {
1509 isc->SanityCheckArtMethodPointerArray(vtable, nullptr);
1511 if (klass->ShouldHaveImt()) {
1512 ImTable* imt = klass->GetImt(pointer_size);
1513 for (size_t i = 0; i < ImTable::kSize; ++i) {
1514 isc->SanityCheckArtMethod(imt->Get(i, pointer_size), nullptr);
1517 if (klass->ShouldHaveEmbeddedVTable()) {
1518 for (int32_t i = 0; i < klass->GetEmbeddedVTableLength(); ++i) {
1519 isc->SanityCheckArtMethod(klass->GetEmbeddedVTableEntry(i, pointer_size), nullptr);
1522 mirror::IfTable* iftable = klass->GetIfTable();
1523 for (int32_t i = 0; i < klass->GetIfTableCount(); ++i) {
1524 if (iftable->GetMethodArrayCount(i) > 0) {
1525 isc->SanityCheckArtMethodPointerArray(iftable->GetMethodArray(i), nullptr);
1532 ImageSanityChecks(gc::Heap* heap, ClassLinker* class_linker)
1533 : spaces_(heap->GetBootImageSpaces()),
1534 pointer_size_(class_linker->GetImagePointerSize()) {
1535 space_begin_.reserve(spaces_.size());
1536 method_sections_.reserve(spaces_.size());
1537 runtime_method_sections_.reserve(spaces_.size());
1538 for (gc::space::ImageSpace* space : spaces_) {
1539 space_begin_.push_back(space->Begin());
1540 auto& header = space->GetImageHeader();
1541 method_sections_.push_back(&header.GetMethodsSection());
1542 runtime_method_sections_.push_back(&header.GetRuntimeMethodsSection());
1546 void SanityCheckArtMethod(ArtMethod* m, ObjPtr<mirror::Class> expected_class)
1547 REQUIRES_SHARED(Locks::mutator_lock_) {
1548 if (m->IsRuntimeMethod()) {
1549 ObjPtr<mirror::Class> declaring_class = m->GetDeclaringClassUnchecked();
1550 CHECK(declaring_class == nullptr) << declaring_class << " " << m->PrettyMethod();
1551 } else if (m->IsCopied()) {
1552 CHECK(m->GetDeclaringClass() != nullptr) << m->PrettyMethod();
1553 } else if (expected_class != nullptr) {
1554 CHECK_EQ(m->GetDeclaringClassUnchecked(), expected_class) << m->PrettyMethod();
1556 if (!spaces_.empty()) {
1557 bool contains = false;
1558 for (size_t i = 0; !contains && i != space_begin_.size(); ++i) {
1559 const size_t offset = reinterpret_cast<uint8_t*>(m) - space_begin_[i];
1560 contains = method_sections_[i]->Contains(offset) ||
1561 runtime_method_sections_[i]->Contains(offset);
1563 CHECK(contains) << m << " not found";
1567 void SanityCheckArtMethodPointerArray(ObjPtr<mirror::PointerArray> arr,
1568 ObjPtr<mirror::Class> expected_class)
1569 REQUIRES_SHARED(Locks::mutator_lock_) {
1570 CHECK(arr != nullptr);
1571 for (int32_t j = 0; j < arr->GetLength(); ++j) {
1572 auto* method = arr->GetElementPtrSize<ArtMethod*>(j, pointer_size_);
1573 // expected_class == null means we are a dex cache.
1574 if (expected_class != nullptr) {
1575 CHECK(method != nullptr);
1577 if (method != nullptr) {
1578 SanityCheckArtMethod(method, expected_class);
1583 void SanityCheckArtMethodPointerArray(ArtMethod** arr, size_t size)
1584 REQUIRES_SHARED(Locks::mutator_lock_) {
1585 CHECK_EQ(arr != nullptr, size != 0u);
1586 if (arr != nullptr) {
1587 bool contains = false;
1588 for (auto space : spaces_) {
1589 auto offset = reinterpret_cast<uint8_t*>(arr) - space->Begin();
1590 if (space->GetImageHeader().GetImageSection(
1591 ImageHeader::kSectionDexCacheArrays).Contains(offset)) {
1598 for (size_t j = 0; j < size; ++j) {
1599 ArtMethod* method = mirror::DexCache::GetElementPtrSize(arr, j, pointer_size_);
1600 // expected_class == null means we are a dex cache.
1601 if (method != nullptr) {
1602 SanityCheckArtMethod(method, nullptr);
1607 const std::vector<gc::space::ImageSpace*>& spaces_;
1608 const PointerSize pointer_size_;
1610 // Cached sections from the spaces.
1611 std::vector<const uint8_t*> space_begin_;
1612 std::vector<const ImageSection*> method_sections_;
1613 std::vector<const ImageSection*> runtime_method_sections_;
1616 bool ClassLinker::AddImageSpace(
1617 gc::space::ImageSpace* space,
1618 Handle<mirror::ClassLoader> class_loader,
1619 jobjectArray dex_elements,
1620 const char* dex_location,
1621 std::vector<std::unique_ptr<const DexFile>>* out_dex_files,
1622 std::string* error_msg) {
1623 DCHECK(out_dex_files != nullptr);
1624 DCHECK(error_msg != nullptr);
1625 const uint64_t start_time = NanoTime();
1626 const bool app_image = class_loader.Get() != nullptr;
1627 const ImageHeader& header = space->GetImageHeader();
1628 ObjPtr<mirror::Object> dex_caches_object = header.GetImageRoot(ImageHeader::kDexCaches);
1629 DCHECK(dex_caches_object != nullptr);
1630 Runtime* const runtime = Runtime::Current();
1631 gc::Heap* const heap = runtime->GetHeap();
1632 Thread* const self = Thread::Current();
1633 // Check that the image is what we are expecting.
1634 if (image_pointer_size_ != space->GetImageHeader().GetPointerSize()) {
1635 *error_msg = StringPrintf("Application image pointer size does not match runtime: %zu vs %zu",
1636 static_cast<size_t>(space->GetImageHeader().GetPointerSize()),
1637 image_pointer_size_);
1640 size_t expected_image_roots = ImageHeader::NumberOfImageRoots(app_image);
1641 if (static_cast<size_t>(header.GetImageRoots()->GetLength()) != expected_image_roots) {
1642 *error_msg = StringPrintf("Expected %zu image roots but got %d",
1643 expected_image_roots,
1644 header.GetImageRoots()->GetLength());
1647 StackHandleScope<3> hs(self);
1648 Handle<mirror::ObjectArray<mirror::DexCache>> dex_caches(
1649 hs.NewHandle(dex_caches_object->AsObjectArray<mirror::DexCache>()));
1650 Handle<mirror::ObjectArray<mirror::Class>> class_roots(hs.NewHandle(
1651 header.GetImageRoot(ImageHeader::kClassRoots)->AsObjectArray<mirror::Class>()));
1652 static_assert(ImageHeader::kClassLoader + 1u == ImageHeader::kImageRootsMax,
1653 "Class loader should be the last image root.");
1654 MutableHandle<mirror::ClassLoader> image_class_loader(hs.NewHandle(
1655 app_image ? header.GetImageRoot(ImageHeader::kClassLoader)->AsClassLoader() : nullptr));
1656 DCHECK(class_roots.Get() != nullptr);
1657 if (class_roots->GetLength() != static_cast<int32_t>(kClassRootsMax)) {
1658 *error_msg = StringPrintf("Expected %d class roots but got %d",
1659 class_roots->GetLength(),
1660 static_cast<int32_t>(kClassRootsMax));
1663 // Check against existing class roots to make sure they match the ones in the boot image.
1664 for (size_t i = 0; i < kClassRootsMax; i++) {
1665 if (class_roots->Get(i) != GetClassRoot(static_cast<ClassRoot>(i))) {
1666 *error_msg = "App image class roots must have pointer equality with runtime ones.";
1670 const OatFile* oat_file = space->GetOatFile();
1671 if (oat_file->GetOatHeader().GetDexFileCount() !=
1672 static_cast<uint32_t>(dex_caches->GetLength())) {
1673 *error_msg = "Dex cache count and dex file count mismatch while trying to initialize from "
1678 StackHandleScope<1> hs2(self);
1679 MutableHandle<mirror::DexCache> h_dex_cache(hs2.NewHandle<mirror::DexCache>(nullptr));
1680 for (int32_t i = 0; i < dex_caches->GetLength(); i++) {
1681 h_dex_cache.Assign(dex_caches->Get(i));
1682 std::string dex_file_location(h_dex_cache->GetLocation()->ToModifiedUtf8());
1683 // TODO: Only store qualified paths.
1684 // If non qualified, qualify it.
1685 if (dex_file_location.find('/') == std::string::npos) {
1686 std::string dex_location_path = dex_location;
1687 const size_t pos = dex_location_path.find_last_of('/');
1688 CHECK_NE(pos, std::string::npos);
1689 dex_location_path = dex_location_path.substr(0, pos + 1); // Keep trailing '/'
1690 dex_file_location = dex_location_path + dex_file_location;
1692 std::unique_ptr<const DexFile> dex_file = OpenOatDexFile(oat_file,
1693 dex_file_location.c_str(),
1695 if (dex_file == nullptr) {
1700 // The current dex file field is bogus, overwrite it so that we can get the dex file in the
1702 h_dex_cache->SetDexFile(dex_file.get());
1703 GcRoot<mirror::Class>* const types = h_dex_cache->GetResolvedTypes();
1704 for (int32_t j = 0, num_types = h_dex_cache->NumResolvedTypes(); j < num_types; j++) {
1705 ObjPtr<mirror::Class> klass = types[j].Read();
1706 if (klass != nullptr) {
1707 DCHECK(!klass->IsErroneous()) << klass->GetStatus();
1711 if (kSanityCheckObjects) {
1712 ImageSanityChecks::CheckPointerArray(heap,
1714 h_dex_cache->GetResolvedMethods(),
1715 h_dex_cache->NumResolvedMethods());
1717 // Register dex files, keep track of existing ones that are conflicts.
1718 AppendToBootClassPath(*dex_file.get(), h_dex_cache);
1720 out_dex_files->push_back(std::move(dex_file));
1724 ScopedObjectAccessUnchecked soa(Thread::Current());
1725 // Check that the class loader resolves the same way as the ones in the image.
1726 // Image class loader [A][B][C][image dex files]
1727 // Class loader = [???][dex_elements][image dex files]
1728 // Need to ensure that [???][dex_elements] == [A][B][C].
1729 // For each class loader, PathClassLoader, the laoder checks the parent first. Also the logic
1730 // for PathClassLoader does this by looping through the array of dex files. To ensure they
1731 // resolve the same way, simply flatten the hierarchy in the way the resolution order would be,
1732 // and check that the dex file names are the same.
1733 if (IsBootClassLoader(soa, image_class_loader.Get())) {
1734 *error_msg = "Unexpected BootClassLoader in app image";
1737 std::list<mirror::String*> image_dex_file_names;
1738 std::string temp_error_msg;
1739 if (!FlattenPathClassLoader(image_class_loader.Get(), &image_dex_file_names, &temp_error_msg)) {
1740 *error_msg = StringPrintf("Failed to flatten image class loader hierarchy '%s'",
1741 temp_error_msg.c_str());
1744 std::list<mirror::String*> loader_dex_file_names;
1745 if (!FlattenPathClassLoader(class_loader.Get(), &loader_dex_file_names, &temp_error_msg)) {
1746 *error_msg = StringPrintf("Failed to flatten class loader hierarchy '%s'",
1747 temp_error_msg.c_str());
1750 // Add the temporary dex path list elements at the end.
1751 auto elements = soa.Decode<mirror::ObjectArray<mirror::Object>>(dex_elements);
1752 for (size_t i = 0, num_elems = elements->GetLength(); i < num_elems; ++i) {
1753 ObjPtr<mirror::Object> element = elements->GetWithoutChecks(i);
1754 if (element != nullptr) {
1755 // If we are somewhere in the middle of the array, there may be nulls at the end.
1756 loader_dex_file_names.push_back(GetDexPathListElementName(element));
1759 // Ignore the number of image dex files since we are adding those to the class loader anyways.
1760 CHECK_GE(static_cast<size_t>(image_dex_file_names.size()),
1761 static_cast<size_t>(dex_caches->GetLength()));
1762 size_t image_count = image_dex_file_names.size() - dex_caches->GetLength();
1763 // Check that the dex file names match.
1764 bool equal = image_count == loader_dex_file_names.size();
1766 auto it1 = image_dex_file_names.begin();
1767 auto it2 = loader_dex_file_names.begin();
1768 for (size_t i = 0; equal && i < image_count; ++i, ++it1, ++it2) {
1769 equal = equal && (*it1)->Equals(*it2);
1773 VLOG(image) << "Image dex files " << image_dex_file_names.size();
1774 for (ObjPtr<mirror::String> name : image_dex_file_names) {
1775 VLOG(image) << name->ToModifiedUtf8();
1777 VLOG(image) << "Loader dex files " << loader_dex_file_names.size();
1778 for (ObjPtr<mirror::String> name : loader_dex_file_names) {
1779 VLOG(image) << name->ToModifiedUtf8();
1781 *error_msg = "Rejecting application image due to class loader mismatch";
1782 // Ignore class loader mismatch for now since these would just use possibly incorrect
1783 // oat code anyways. The structural class check should be done in the parent.
1787 if (kSanityCheckObjects) {
1788 for (int32_t i = 0; i < dex_caches->GetLength(); i++) {
1789 auto* dex_cache = dex_caches->Get(i);
1790 for (size_t j = 0; j < dex_cache->NumResolvedFields(); ++j) {
1791 auto* field = dex_cache->GetResolvedField(j, image_pointer_size_);
1792 if (field != nullptr) {
1793 CHECK(field->GetDeclaringClass()->GetClass() != nullptr);
1798 ImageSanityChecks::CheckObjects(heap, this);
1802 // Set entry point to interpreter if in InterpretOnly mode.
1803 if (!runtime->IsAotCompiler() && runtime->GetInstrumentation()->InterpretOnly()) {
1804 SetInterpreterEntrypointArtMethodVisitor visitor(image_pointer_size_);
1805 header.VisitPackedArtMethods(&visitor, space->Begin(), image_pointer_size_);
1808 ClassTable* class_table = nullptr;
1810 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_);
1811 class_table = InsertClassTableForClassLoader(class_loader.Get());
1813 // If we have a class table section, read it and use it for verification in
1814 // UpdateAppImageClassLoadersAndDexCaches.
1815 ClassTable::ClassSet temp_set;
1816 const ImageSection& class_table_section = header.GetImageSection(ImageHeader::kSectionClassTable);
1817 const bool added_class_table = class_table_section.Size() > 0u;
1818 if (added_class_table) {
1819 const uint64_t start_time2 = NanoTime();
1820 size_t read_count = 0;
1821 temp_set = ClassTable::ClassSet(space->Begin() + class_table_section.Offset(),
1824 VLOG(image) << "Adding class table classes took " << PrettyDuration(NanoTime() - start_time2);
1827 bool forward_dex_cache_arrays = false;
1828 if (!UpdateAppImageClassLoadersAndDexCaches(space,
1832 /*out*/&forward_dex_cache_arrays,
1833 /*out*/error_msg)) {
1836 // Update class loader and resolved strings. If added_class_table is false, the resolved
1837 // strings were forwarded UpdateAppImageClassLoadersAndDexCaches.
1838 UpdateClassLoaderVisitor visitor(space, class_loader.Get());
1839 for (const ClassTable::TableSlot& root : temp_set) {
1840 visitor(root.Read());
1842 // forward_dex_cache_arrays is true iff we copied all of the dex cache arrays into the .bss.
1843 // In this case, madvise away the dex cache arrays section of the image to reduce RAM usage and
1844 // mark as PROT_NONE to catch any invalid accesses.
1845 if (forward_dex_cache_arrays) {
1846 const ImageSection& dex_cache_section = header.GetImageSection(
1847 ImageHeader::kSectionDexCacheArrays);
1848 uint8_t* section_begin = AlignUp(space->Begin() + dex_cache_section.Offset(), kPageSize);
1849 uint8_t* section_end = AlignDown(space->Begin() + dex_cache_section.End(), kPageSize);
1850 if (section_begin < section_end) {
1851 madvise(section_begin, section_end - section_begin, MADV_DONTNEED);
1852 mprotect(section_begin, section_end - section_begin, PROT_NONE);
1853 VLOG(image) << "Released and protected dex cache array image section from "
1854 << reinterpret_cast<const void*>(section_begin) << "-"
1855 << reinterpret_cast<const void*>(section_end);
1859 if (!oat_file->GetBssGcRoots().empty()) {
1860 // Insert oat file to class table for visiting .bss GC roots.
1861 class_table->InsertOatFile(oat_file);
1863 if (added_class_table) {
1864 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_);
1865 class_table->AddClassSet(std::move(temp_set));
1867 if (kIsDebugBuild && app_image) {
1868 // This verification needs to happen after the classes have been added to the class loader.
1869 // Since it ensures classes are in the class table.
1870 VerifyClassInTableArtMethodVisitor visitor2(class_table);
1871 header.VisitPackedArtMethods(&visitor2, space->Begin(), kRuntimePointerSize);
1873 VLOG(class_linker) << "Adding image space took " << PrettyDuration(NanoTime() - start_time);
1877 bool ClassLinker::ClassInClassTable(ObjPtr<mirror::Class> klass) {
1878 ClassTable* const class_table = ClassTableForClassLoader(klass->GetClassLoader());
1879 return class_table != nullptr && class_table->Contains(klass);
1882 void ClassLinker::VisitClassRoots(RootVisitor* visitor, VisitRootFlags flags) {
1883 // Acquire tracing_enabled before locking class linker lock to prevent lock order violation. Since
1884 // enabling tracing requires the mutator lock, there are no race conditions here.
1885 const bool tracing_enabled = Trace::IsTracingEnabled();
1886 Thread* const self = Thread::Current();
1887 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_);
1888 if ((flags & kVisitRootFlagAllRoots) != 0) {
1889 // Argument for how root visiting deals with ArtField and ArtMethod roots.
1890 // There is 3 GC cases to handle:
1891 // Non moving concurrent:
1892 // This case is easy to handle since the reference members of ArtMethod and ArtFields are held
1893 // live by the class and class roots.
1895 // Moving non-concurrent:
1896 // This case needs to call visit VisitNativeRoots in case the classes or dex cache arrays move.
1897 // To prevent missing roots, this case needs to ensure that there is no
1898 // suspend points between the point which we allocate ArtMethod arrays and place them in a
1899 // class which is in the class table.
1901 // Moving concurrent:
1902 // Need to make sure to not copy ArtMethods without doing read barriers since the roots are
1903 // marked concurrently and we don't hold the classlinker_classes_lock_ when we do the copy.
1905 // Use an unbuffered visitor since the class table uses a temporary GcRoot for holding decoded
1906 // ClassTable::TableSlot. The buffered root visiting would access a stale stack location for
1908 UnbufferedRootVisitor root_visitor(visitor, RootInfo(kRootStickyClass));
1909 boot_class_table_.VisitRoots(root_visitor);
1910 // If tracing is enabled, then mark all the class loaders to prevent unloading.
1911 if ((flags & kVisitRootFlagClassLoader) != 0 || tracing_enabled) {
1912 for (const ClassLoaderData& data : class_loaders_) {
1913 GcRoot<mirror::Object> root(GcRoot<mirror::Object>(self->DecodeJObject(data.weak_root)));
1914 root.VisitRoot(visitor, RootInfo(kRootVMInternal));
1917 } else if ((flags & kVisitRootFlagNewRoots) != 0) {
1918 for (auto& root : new_class_roots_) {
1919 ObjPtr<mirror::Class> old_ref = root.Read<kWithoutReadBarrier>();
1920 root.VisitRoot(visitor, RootInfo(kRootStickyClass));
1921 ObjPtr<mirror::Class> new_ref = root.Read<kWithoutReadBarrier>();
1922 // Concurrent moving GC marked new roots through the to-space invariant.
1923 CHECK_EQ(new_ref, old_ref);
1925 for (const OatFile* oat_file : new_bss_roots_boot_oat_files_) {
1926 for (GcRoot<mirror::Object>& root : oat_file->GetBssGcRoots()) {
1927 ObjPtr<mirror::Object> old_ref = root.Read<kWithoutReadBarrier>();
1928 if (old_ref != nullptr) {
1929 DCHECK(old_ref->IsClass());
1930 root.VisitRoot(visitor, RootInfo(kRootStickyClass));
1931 ObjPtr<mirror::Object> new_ref = root.Read<kWithoutReadBarrier>();
1932 // Concurrent moving GC marked new roots through the to-space invariant.
1933 CHECK_EQ(new_ref, old_ref);
1938 if ((flags & kVisitRootFlagClearRootLog) != 0) {
1939 new_class_roots_.clear();
1940 new_bss_roots_boot_oat_files_.clear();
1942 if ((flags & kVisitRootFlagStartLoggingNewRoots) != 0) {
1943 log_new_roots_ = true;
1944 } else if ((flags & kVisitRootFlagStopLoggingNewRoots) != 0) {
1945 log_new_roots_ = false;
1947 // We deliberately ignore the class roots in the image since we
1948 // handle image roots by using the MS/CMS rescanning of dirty cards.
1951 // Keep in sync with InitCallback. Anything we visit, we need to
1952 // reinit references to when reinitializing a ClassLinker from a
1954 void ClassLinker::VisitRoots(RootVisitor* visitor, VisitRootFlags flags) {
1955 class_roots_.VisitRootIfNonNull(visitor, RootInfo(kRootVMInternal));
1956 VisitClassRoots(visitor, flags);
1957 array_iftable_.VisitRootIfNonNull(visitor, RootInfo(kRootVMInternal));
1958 // Instead of visiting the find_array_class_cache_ drop it so that it doesn't prevent class
1959 // unloading if we are marking roots.
1960 DropFindArrayClassCache();
1963 class VisitClassLoaderClassesVisitor : public ClassLoaderVisitor {
1965 explicit VisitClassLoaderClassesVisitor(ClassVisitor* visitor)
1966 : visitor_(visitor),
1969 void Visit(ObjPtr<mirror::ClassLoader> class_loader)
1970 REQUIRES_SHARED(Locks::classlinker_classes_lock_, Locks::mutator_lock_) OVERRIDE {
1971 ClassTable* const class_table = class_loader->GetClassTable();
1972 if (!done_ && class_table != nullptr) {
1973 DefiningClassLoaderFilterVisitor visitor(class_loader, visitor_);
1974 if (!class_table->Visit(visitor)) {
1975 // If the visitor ClassTable returns false it means that we don't need to continue.
1982 // Class visitor that limits the class visits from a ClassTable to the classes with
1983 // the provided defining class loader. This filter is used to avoid multiple visits
1984 // of the same class which can be recorded for multiple initiating class loaders.
1985 class DefiningClassLoaderFilterVisitor : public ClassVisitor {
1987 DefiningClassLoaderFilterVisitor(ObjPtr<mirror::ClassLoader> defining_class_loader,
1988 ClassVisitor* visitor)
1989 : defining_class_loader_(defining_class_loader), visitor_(visitor) { }
1991 bool operator()(ObjPtr<mirror::Class> klass) OVERRIDE REQUIRES_SHARED(Locks::mutator_lock_) {
1992 if (klass->GetClassLoader() != defining_class_loader_) {
1995 return (*visitor_)(klass);
1998 ObjPtr<mirror::ClassLoader> const defining_class_loader_;
1999 ClassVisitor* const visitor_;
2002 ClassVisitor* const visitor_;
2003 // If done is true then we don't need to do any more visiting.
2007 void ClassLinker::VisitClassesInternal(ClassVisitor* visitor) {
2008 if (boot_class_table_.Visit(*visitor)) {
2009 VisitClassLoaderClassesVisitor loader_visitor(visitor);
2010 VisitClassLoaders(&loader_visitor);
2014 void ClassLinker::VisitClasses(ClassVisitor* visitor) {
2015 Thread* const self = Thread::Current();
2016 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_);
2017 // Not safe to have thread suspension when we are holding a lock.
2018 if (self != nullptr) {
2019 ScopedAssertNoThreadSuspension nts(__FUNCTION__);
2020 VisitClassesInternal(visitor);
2022 VisitClassesInternal(visitor);
2026 class GetClassesInToVector : public ClassVisitor {
2028 bool operator()(ObjPtr<mirror::Class> klass) OVERRIDE {
2029 classes_.push_back(klass);
2032 std::vector<ObjPtr<mirror::Class>> classes_;
2035 class GetClassInToObjectArray : public ClassVisitor {
2037 explicit GetClassInToObjectArray(mirror::ObjectArray<mirror::Class>* arr)
2038 : arr_(arr), index_(0) {}
2040 bool operator()(ObjPtr<mirror::Class> klass) OVERRIDE REQUIRES_SHARED(Locks::mutator_lock_) {
2042 if (index_ <= arr_->GetLength()) {
2043 arr_->Set(index_ - 1, klass);
2049 bool Succeeded() const REQUIRES_SHARED(Locks::mutator_lock_) {
2050 return index_ <= arr_->GetLength();
2054 mirror::ObjectArray<mirror::Class>* const arr_;
2058 void ClassLinker::VisitClassesWithoutClassesLock(ClassVisitor* visitor) {
2059 // TODO: it may be possible to avoid secondary storage if we iterate over dex caches. The problem
2060 // is avoiding duplicates.
2061 if (!kMovingClasses) {
2062 ScopedAssertNoThreadSuspension nts(__FUNCTION__);
2063 GetClassesInToVector accumulator;
2064 VisitClasses(&accumulator);
2065 for (ObjPtr<mirror::Class> klass : accumulator.classes_) {
2066 if (!visitor->operator()(klass)) {
2071 Thread* const self = Thread::Current();
2072 StackHandleScope<1> hs(self);
2073 auto classes = hs.NewHandle<mirror::ObjectArray<mirror::Class>>(nullptr);
2074 // We size the array assuming classes won't be added to the class table during the visit.
2075 // If this assumption fails we iterate again.
2077 size_t class_table_size;
2079 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_);
2080 // Add 100 in case new classes get loaded when we are filling in the object array.
2081 class_table_size = NumZygoteClasses() + NumNonZygoteClasses() + 100;
2083 ObjPtr<mirror::Class> class_type = mirror::Class::GetJavaLangClass();
2084 ObjPtr<mirror::Class> array_of_class = FindArrayClass(self, &class_type);
2086 mirror::ObjectArray<mirror::Class>::Alloc(self, array_of_class, class_table_size));
2087 CHECK(classes.Get() != nullptr); // OOME.
2088 GetClassInToObjectArray accumulator(classes.Get());
2089 VisitClasses(&accumulator);
2090 if (accumulator.Succeeded()) {
2094 for (int32_t i = 0; i < classes->GetLength(); ++i) {
2095 // If the class table shrank during creation of the clases array we expect null elements. If
2096 // the class table grew then the loop repeats. If classes are created after the loop has
2097 // finished then we don't visit.
2098 ObjPtr<mirror::Class> klass = classes->Get(i);
2099 if (klass != nullptr && !visitor->operator()(klass)) {
2106 ClassLinker::~ClassLinker() {
2107 mirror::Class::ResetClass();
2108 mirror::Constructor::ResetClass();
2109 mirror::Field::ResetClass();
2110 mirror::Method::ResetClass();
2111 mirror::Reference::ResetClass();
2112 mirror::StackTraceElement::ResetClass();
2113 mirror::String::ResetClass();
2114 mirror::Throwable::ResetClass();
2115 mirror::BooleanArray::ResetArrayClass();
2116 mirror::ByteArray::ResetArrayClass();
2117 mirror::CharArray::ResetArrayClass();
2118 mirror::Constructor::ResetArrayClass();
2119 mirror::DoubleArray::ResetArrayClass();
2120 mirror::Field::ResetArrayClass();
2121 mirror::FloatArray::ResetArrayClass();
2122 mirror::Method::ResetArrayClass();
2123 mirror::IntArray::ResetArrayClass();
2124 mirror::LongArray::ResetArrayClass();
2125 mirror::ShortArray::ResetArrayClass();
2126 mirror::MethodType::ResetClass();
2127 mirror::MethodHandleImpl::ResetClass();
2128 mirror::EmulatedStackFrame::ResetClass();
2129 Thread* const self = Thread::Current();
2130 for (const ClassLoaderData& data : class_loaders_) {
2131 DeleteClassLoader(self, data);
2133 class_loaders_.clear();
2136 void ClassLinker::DeleteClassLoader(Thread* self, const ClassLoaderData& data) {
2137 Runtime* const runtime = Runtime::Current();
2138 JavaVMExt* const vm = runtime->GetJavaVM();
2139 vm->DeleteWeakGlobalRef(self, data.weak_root);
2140 // Notify the JIT that we need to remove the methods and/or profiling info.
2141 if (runtime->GetJit() != nullptr) {
2142 jit::JitCodeCache* code_cache = runtime->GetJit()->GetCodeCache();
2143 if (code_cache != nullptr) {
2144 code_cache->RemoveMethodsIn(self, *data.allocator);
2147 delete data.allocator;
2148 delete data.class_table;
2151 mirror::PointerArray* ClassLinker::AllocPointerArray(Thread* self, size_t length) {
2152 return down_cast<mirror::PointerArray*>(
2153 image_pointer_size_ == PointerSize::k64
2154 ? static_cast<mirror::Array*>(mirror::LongArray::Alloc(self, length))
2155 : static_cast<mirror::Array*>(mirror::IntArray::Alloc(self, length)));
2158 mirror::DexCache* ClassLinker::AllocDexCache(ObjPtr<mirror::String>* out_location,
2160 const DexFile& dex_file) {
2161 StackHandleScope<1> hs(self);
2162 DCHECK(out_location != nullptr);
2163 auto dex_cache(hs.NewHandle(ObjPtr<mirror::DexCache>::DownCast(
2164 GetClassRoot(kJavaLangDexCache)->AllocObject(self))));
2165 if (dex_cache.Get() == nullptr) {
2166 self->AssertPendingOOMException();
2169 ObjPtr<mirror::String> location = intern_table_->InternStrong(dex_file.GetLocation().c_str());
2170 if (location == nullptr) {
2171 self->AssertPendingOOMException();
2174 *out_location = location;
2175 return dex_cache.Get();
2178 mirror::DexCache* ClassLinker::AllocAndInitializeDexCache(Thread* self,
2179 const DexFile& dex_file,
2180 LinearAlloc* linear_alloc) {
2181 ObjPtr<mirror::String> location = nullptr;
2182 ObjPtr<mirror::DexCache> dex_cache = AllocDexCache(&location, self, dex_file);
2183 if (dex_cache != nullptr) {
2184 WriterMutexLock mu(self, *Locks::dex_lock_);
2185 DCHECK(location != nullptr);
2186 mirror::DexCache::InitializeDexCache(self,
2191 image_pointer_size_);
2193 return dex_cache.Ptr();
2196 mirror::Class* ClassLinker::AllocClass(Thread* self,
2197 ObjPtr<mirror::Class> java_lang_Class,
2198 uint32_t class_size) {
2199 DCHECK_GE(class_size, sizeof(mirror::Class));
2200 gc::Heap* heap = Runtime::Current()->GetHeap();
2201 mirror::Class::InitializeClassVisitor visitor(class_size);
2202 ObjPtr<mirror::Object> k = kMovingClasses ?
2203 heap->AllocObject<true>(self, java_lang_Class, class_size, visitor) :
2204 heap->AllocNonMovableObject<true>(self, java_lang_Class, class_size, visitor);
2205 if (UNLIKELY(k == nullptr)) {
2206 self->AssertPendingOOMException();
2209 return k->AsClass();
2212 mirror::Class* ClassLinker::AllocClass(Thread* self, uint32_t class_size) {
2213 return AllocClass(self, GetClassRoot(kJavaLangClass), class_size);
2216 mirror::ObjectArray<mirror::StackTraceElement>* ClassLinker::AllocStackTraceElementArray(
2219 return mirror::ObjectArray<mirror::StackTraceElement>::Alloc(
2220 self, GetClassRoot(kJavaLangStackTraceElementArrayClass), length);
2223 mirror::Class* ClassLinker::EnsureResolved(Thread* self,
2224 const char* descriptor,
2225 ObjPtr<mirror::Class> klass) {
2226 DCHECK(klass != nullptr);
2227 if (kIsDebugBuild) {
2228 StackHandleScope<1> hs(self);
2229 HandleWrapperObjPtr<mirror::Class> h = hs.NewHandleWrapper(&klass);
2230 Thread::PoisonObjectPointersIfDebug();
2233 // For temporary classes we must wait for them to be retired.
2234 if (init_done_ && klass->IsTemp()) {
2235 CHECK(!klass->IsResolved());
2236 if (klass->IsErroneousUnresolved()) {
2237 ThrowEarlierClassFailure(klass);
2240 StackHandleScope<1> hs(self);
2241 Handle<mirror::Class> h_class(hs.NewHandle(klass));
2242 ObjectLock<mirror::Class> lock(self, h_class);
2243 // Loop and wait for the resolving thread to retire this class.
2244 while (!h_class->IsRetired() && !h_class->IsErroneousUnresolved()) {
2245 lock.WaitIgnoringInterrupts();
2247 if (h_class->IsErroneousUnresolved()) {
2248 ThrowEarlierClassFailure(h_class.Get());
2251 CHECK(h_class->IsRetired());
2252 // Get the updated class from class table.
2253 klass = LookupClass(self, descriptor, h_class.Get()->GetClassLoader());
2256 // Wait for the class if it has not already been linked.
2258 // Maximum number of yield iterations until we start sleeping.
2259 static const size_t kNumYieldIterations = 1000;
2260 // How long each sleep is in us.
2261 static const size_t kSleepDurationUS = 1000; // 1 ms.
2262 while (!klass->IsResolved() && !klass->IsErroneousUnresolved()) {
2263 StackHandleScope<1> hs(self);
2264 HandleWrapperObjPtr<mirror::Class> h_class(hs.NewHandleWrapper(&klass));
2266 ObjectTryLock<mirror::Class> lock(self, h_class);
2267 // Can not use a monitor wait here since it may block when returning and deadlock if another
2268 // thread has locked klass.
2269 if (lock.Acquired()) {
2270 // Check for circular dependencies between classes, the lock is required for SetStatus.
2271 if (!h_class->IsResolved() && h_class->GetClinitThreadId() == self->GetTid()) {
2272 ThrowClassCircularityError(h_class.Get());
2273 mirror::Class::SetStatus(h_class, mirror::Class::kStatusErrorUnresolved, self);
2279 // Handle wrapper deals with klass moving.
2280 ScopedThreadSuspension sts(self, kSuspended);
2281 if (index < kNumYieldIterations) {
2284 usleep(kSleepDurationUS);
2290 if (klass->IsErroneousUnresolved()) {
2291 ThrowEarlierClassFailure(klass);
2294 // Return the loaded class. No exceptions should be pending.
2295 CHECK(klass->IsResolved()) << klass->PrettyClass();
2296 self->AssertNoPendingException();
2300 typedef std::pair<const DexFile*, const DexFile::ClassDef*> ClassPathEntry;
2302 // Search a collection of DexFiles for a descriptor
2303 ClassPathEntry FindInClassPath(const char* descriptor,
2304 size_t hash, const std::vector<const DexFile*>& class_path) {
2305 for (const DexFile* dex_file : class_path) {
2306 const DexFile::ClassDef* dex_class_def = OatDexFile::FindClassDef(*dex_file, descriptor, hash);
2307 if (dex_class_def != nullptr) {
2308 return ClassPathEntry(dex_file, dex_class_def);
2311 return ClassPathEntry(nullptr, nullptr);
2314 bool ClassLinker::FindClassInBaseDexClassLoader(ScopedObjectAccessAlreadyRunnable& soa,
2316 const char* descriptor,
2318 Handle<mirror::ClassLoader> class_loader,
2319 ObjPtr<mirror::Class>* result) {
2320 // Termination case: boot class-loader.
2321 if (IsBootClassLoader(soa, class_loader.Get())) {
2322 // The boot class loader, search the boot class path.
2323 ClassPathEntry pair = FindInClassPath(descriptor, hash, boot_class_path_);
2324 if (pair.second != nullptr) {
2325 ObjPtr<mirror::Class> klass = LookupClass(self, descriptor, hash, nullptr);
2326 if (klass != nullptr) {
2327 *result = EnsureResolved(self, descriptor, klass);
2329 *result = DefineClass(self,
2332 ScopedNullHandle<mirror::ClassLoader>(),
2336 if (*result == nullptr) {
2337 CHECK(self->IsExceptionPending()) << descriptor;
2338 self->ClearException();
2346 // Unsupported class-loader?
2347 if (soa.Decode<mirror::Class>(WellKnownClasses::dalvik_system_PathClassLoader) !=
2348 class_loader->GetClass()) {
2349 // PathClassLoader is the most common case, so it's the one we check first. For secondary dex
2350 // files, we also check DexClassLoader here.
2351 if (soa.Decode<mirror::Class>(WellKnownClasses::dalvik_system_DexClassLoader) !=
2352 class_loader->GetClass()) {
2358 // Handles as RegisterDexFile may allocate dex caches (and cause thread suspension).
2359 StackHandleScope<4> hs(self);
2360 Handle<mirror::ClassLoader> h_parent(hs.NewHandle(class_loader->GetParent()));
2361 bool recursive_result = FindClassInBaseDexClassLoader(soa,
2368 if (!recursive_result) {
2369 // Something wrong up the chain.
2373 if (*result != nullptr) {
2374 // Found the class up the chain.
2378 // Handle this step.
2379 // Handle as if this is the child PathClassLoader.
2380 // The class loader is a PathClassLoader which inherits from BaseDexClassLoader.
2381 // We need to get the DexPathList and loop through it.
2382 ArtField* const cookie_field =
2383 jni::DecodeArtField(WellKnownClasses::dalvik_system_DexFile_cookie);
2384 ArtField* const dex_file_field =
2385 jni::DecodeArtField(WellKnownClasses::dalvik_system_DexPathList__Element_dexFile);
2386 ObjPtr<mirror::Object> dex_path_list =
2387 jni::DecodeArtField(WellKnownClasses::dalvik_system_BaseDexClassLoader_pathList)->
2388 GetObject(class_loader.Get());
2389 if (dex_path_list != nullptr && dex_file_field != nullptr && cookie_field != nullptr) {
2390 // DexPathList has an array dexElements of Elements[] which each contain a dex file.
2391 ObjPtr<mirror::Object> dex_elements_obj =
2392 jni::DecodeArtField(WellKnownClasses::dalvik_system_DexPathList_dexElements)->
2393 GetObject(dex_path_list);
2394 // Loop through each dalvik.system.DexPathList$Element's dalvik.system.DexFile and look
2395 // at the mCookie which is a DexFile vector.
2396 if (dex_elements_obj != nullptr) {
2397 Handle<mirror::ObjectArray<mirror::Object>> dex_elements =
2398 hs.NewHandle(dex_elements_obj->AsObjectArray<mirror::Object>());
2399 for (int32_t i = 0; i < dex_elements->GetLength(); ++i) {
2400 ObjPtr<mirror::Object> element = dex_elements->GetWithoutChecks(i);
2401 if (element == nullptr) {
2402 // Should never happen, fall back to java code to throw a NPE.
2405 ObjPtr<mirror::Object> dex_file = dex_file_field->GetObject(element);
2406 if (dex_file != nullptr) {
2407 ObjPtr<mirror::LongArray> long_array = cookie_field->GetObject(dex_file)->AsLongArray();
2408 if (long_array == nullptr) {
2409 // This should never happen so log a warning.
2410 LOG(WARNING) << "Null DexFile::mCookie for " << descriptor;
2413 int32_t long_array_size = long_array->GetLength();
2414 // First element is the oat file.
2415 for (int32_t j = kDexFileIndexStart; j < long_array_size; ++j) {
2416 const DexFile* cp_dex_file = reinterpret_cast<const DexFile*>(static_cast<uintptr_t>(
2417 long_array->GetWithoutChecks(j)));
2418 const DexFile::ClassDef* dex_class_def =
2419 OatDexFile::FindClassDef(*cp_dex_file, descriptor, hash);
2420 if (dex_class_def != nullptr) {
2421 ObjPtr<mirror::Class> klass = DefineClass(self,
2427 if (klass == nullptr) {
2428 CHECK(self->IsExceptionPending()) << descriptor;
2429 self->ClearException();
2430 // TODO: Is it really right to break here, and not check the other dex files?
2440 self->AssertNoPendingException();
2443 // Result is still null from the parent call, no need to set it again...
2447 mirror::Class* ClassLinker::FindClass(Thread* self,
2448 const char* descriptor,
2449 Handle<mirror::ClassLoader> class_loader) {
2450 DCHECK_NE(*descriptor, '\0') << "descriptor is empty string";
2451 DCHECK(self != nullptr);
2452 self->AssertNoPendingException();
2453 self->PoisonObjectPointers(); // For DefineClass, CreateArrayClass, etc...
2454 if (descriptor[1] == '\0') {
2455 // only the descriptors of primitive types should be 1 character long, also avoid class lookup
2456 // for primitive classes that aren't backed by dex files.
2457 return FindPrimitiveClass(descriptor[0]);
2459 const size_t hash = ComputeModifiedUtf8Hash(descriptor);
2460 // Find the class in the loaded classes table.
2461 ObjPtr<mirror::Class> klass = LookupClass(self, descriptor, hash, class_loader.Get());
2462 if (klass != nullptr) {
2463 return EnsureResolved(self, descriptor, klass);
2465 // Class is not yet loaded.
2466 if (descriptor[0] != '[' && class_loader.Get() == nullptr) {
2467 // Non-array class and the boot class loader, search the boot class path.
2468 ClassPathEntry pair = FindInClassPath(descriptor, hash, boot_class_path_);
2469 if (pair.second != nullptr) {
2470 return DefineClass(self,
2473 ScopedNullHandle<mirror::ClassLoader>(),
2477 // The boot class loader is searched ahead of the application class loader, failures are
2478 // expected and will be wrapped in a ClassNotFoundException. Use the pre-allocated error to
2479 // trigger the chaining with a proper stack trace.
2480 ObjPtr<mirror::Throwable> pre_allocated =
2481 Runtime::Current()->GetPreAllocatedNoClassDefFoundError();
2482 self->SetException(pre_allocated);
2486 ObjPtr<mirror::Class> result_ptr;
2487 bool descriptor_equals;
2488 if (descriptor[0] == '[') {
2489 result_ptr = CreateArrayClass(self, descriptor, hash, class_loader);
2490 DCHECK_EQ(result_ptr == nullptr, self->IsExceptionPending());
2491 DCHECK(result_ptr == nullptr || result_ptr->DescriptorEquals(descriptor));
2492 descriptor_equals = true;
2494 ScopedObjectAccessUnchecked soa(self);
2495 bool known_hierarchy =
2496 FindClassInBaseDexClassLoader(soa, self, descriptor, hash, class_loader, &result_ptr);
2497 if (result_ptr != nullptr) {
2498 // The chain was understood and we found the class. We still need to add the class to
2499 // the class table to protect from racy programs that can try and redefine the path list
2500 // which would change the Class<?> returned for subsequent evaluation of const-class.
2501 DCHECK(known_hierarchy);
2502 DCHECK(result_ptr->DescriptorEquals(descriptor));
2503 descriptor_equals = true;
2505 // Either the chain wasn't understood or the class wasn't found.
2507 // If the chain was understood but we did not find the class, let the Java-side
2508 // rediscover all this and throw the exception with the right stack trace. Note that
2509 // the Java-side could still succeed for racy programs if another thread is actively
2510 // modifying the class loader's path list.
2512 if (!self->CanCallIntoJava()) {
2513 // Oops, we can't call into java so we can't run actual class-loader code.
2514 // This is true for e.g. for the compiler (jit or aot).
2515 ObjPtr<mirror::Throwable> pre_allocated =
2516 Runtime::Current()->GetPreAllocatedNoClassDefFoundError();
2517 self->SetException(pre_allocated);
2521 ScopedLocalRef<jobject> class_loader_object(
2522 soa.Env(), soa.AddLocalReference<jobject>(class_loader.Get()));
2523 std::string class_name_string(DescriptorToDot(descriptor));
2524 ScopedLocalRef<jobject> result(soa.Env(), nullptr);
2526 ScopedThreadStateChange tsc(self, kNative);
2527 ScopedLocalRef<jobject> class_name_object(
2528 soa.Env(), soa.Env()->NewStringUTF(class_name_string.c_str()));
2529 if (class_name_object.get() == nullptr) {
2530 DCHECK(self->IsExceptionPending()); // OOME.
2533 CHECK(class_loader_object.get() != nullptr);
2534 result.reset(soa.Env()->CallObjectMethod(class_loader_object.get(),
2535 WellKnownClasses::java_lang_ClassLoader_loadClass,
2536 class_name_object.get()));
2538 if (result.get() == nullptr && !self->IsExceptionPending()) {
2539 // broken loader - throw NPE to be compatible with Dalvik
2540 ThrowNullPointerException(StringPrintf("ClassLoader.loadClass returned null for %s",
2541 class_name_string.c_str()).c_str());
2544 result_ptr = soa.Decode<mirror::Class>(result.get());
2545 // Check the name of the returned class.
2546 descriptor_equals = (result_ptr != nullptr) && result_ptr->DescriptorEquals(descriptor);
2550 if (self->IsExceptionPending()) {
2551 // If the ClassLoader threw or array class allocation failed, pass that exception up.
2552 // However, to comply with the RI behavior, first check if another thread succeeded.
2553 result_ptr = LookupClass(self, descriptor, hash, class_loader.Get());
2554 if (result_ptr != nullptr && !result_ptr->IsErroneous()) {
2555 self->ClearException();
2556 return EnsureResolved(self, descriptor, result_ptr);
2561 // Try to insert the class to the class table, checking for mismatch.
2562 ObjPtr<mirror::Class> old;
2564 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_);
2565 ClassTable* const class_table = InsertClassTableForClassLoader(class_loader.Get());
2566 old = class_table->Lookup(descriptor, hash);
2567 if (old == nullptr) {
2568 old = result_ptr; // For the comparison below, after releasing the lock.
2569 if (descriptor_equals) {
2570 class_table->InsertWithHash(result_ptr.Ptr(), hash);
2571 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(class_loader.Get());
2572 } // else throw below, after releasing the lock.
2575 if (UNLIKELY(old != result_ptr)) {
2576 // Return `old` (even if `!descriptor_equals`) to mimic the RI behavior for parallel
2577 // capable class loaders. (All class loaders are considered parallel capable on Android.)
2578 mirror::Class* loader_class = class_loader->GetClass();
2579 const char* loader_class_name =
2580 loader_class->GetDexFile().StringByTypeIdx(loader_class->GetDexTypeIndex());
2581 LOG(WARNING) << "Initiating class loader of type " << DescriptorToDot(loader_class_name)
2582 << " is not well-behaved; it returned a different Class for racing loadClass(\""
2583 << DescriptorToDot(descriptor) << "\").";
2584 return EnsureResolved(self, descriptor, old);
2586 if (UNLIKELY(!descriptor_equals)) {
2587 std::string result_storage;
2588 const char* result_name = result_ptr->GetDescriptor(&result_storage);
2589 std::string loader_storage;
2590 const char* loader_class_name = class_loader->GetClass()->GetDescriptor(&loader_storage);
2591 ThrowNoClassDefFoundError(
2592 "Initiating class loader of type %s returned class %s instead of %s.",
2593 DescriptorToDot(loader_class_name).c_str(),
2594 DescriptorToDot(result_name).c_str(),
2595 DescriptorToDot(descriptor).c_str());
2598 // success, return mirror::Class*
2599 return result_ptr.Ptr();
2602 mirror::Class* ClassLinker::DefineClass(Thread* self,
2603 const char* descriptor,
2605 Handle<mirror::ClassLoader> class_loader,
2606 const DexFile& dex_file,
2607 const DexFile::ClassDef& dex_class_def) {
2608 StackHandleScope<3> hs(self);
2609 auto klass = hs.NewHandle<mirror::Class>(nullptr);
2611 // Load the class from the dex file.
2612 if (UNLIKELY(!init_done_)) {
2613 // finish up init of hand crafted class_roots_
2614 if (strcmp(descriptor, "Ljava/lang/Object;") == 0) {
2615 klass.Assign(GetClassRoot(kJavaLangObject));
2616 } else if (strcmp(descriptor, "Ljava/lang/Class;") == 0) {
2617 klass.Assign(GetClassRoot(kJavaLangClass));
2618 } else if (strcmp(descriptor, "Ljava/lang/String;") == 0) {
2619 klass.Assign(GetClassRoot(kJavaLangString));
2620 } else if (strcmp(descriptor, "Ljava/lang/ref/Reference;") == 0) {
2621 klass.Assign(GetClassRoot(kJavaLangRefReference));
2622 } else if (strcmp(descriptor, "Ljava/lang/DexCache;") == 0) {
2623 klass.Assign(GetClassRoot(kJavaLangDexCache));
2624 } else if (strcmp(descriptor, "Ldalvik/system/ClassExt;") == 0) {
2625 klass.Assign(GetClassRoot(kDalvikSystemClassExt));
2629 if (klass.Get() == nullptr) {
2630 // Allocate a class with the status of not ready.
2631 // Interface object should get the right size here. Regular class will
2632 // figure out the right size later and be replaced with one of the right
2633 // size when the class becomes resolved.
2634 klass.Assign(AllocClass(self, SizeOfClassWithoutEmbeddedTables(dex_file, dex_class_def)));
2636 if (UNLIKELY(klass.Get() == nullptr)) {
2637 self->AssertPendingOOMException();
2640 // Get the real dex file. This will return the input if there aren't any callbacks or they do
2642 DexFile const* new_dex_file = nullptr;
2643 DexFile::ClassDef const* new_class_def = nullptr;
2644 // TODO We should ideally figure out some way to move this after we get a lock on the klass so it
2645 // will only be called once.
2646 Runtime::Current()->GetRuntimeCallbacks()->ClassPreDefine(descriptor,
2653 // Check to see if an exception happened during runtime callbacks. Return if so.
2654 if (self->IsExceptionPending()) {
2657 ObjPtr<mirror::DexCache> dex_cache = RegisterDexFile(*new_dex_file, class_loader.Get());
2658 if (dex_cache == nullptr) {
2659 self->AssertPendingOOMException();
2662 klass->SetDexCache(dex_cache);
2663 SetupClass(*new_dex_file, *new_class_def, klass, class_loader.Get());
2665 // Mark the string class by setting its access flag.
2666 if (UNLIKELY(!init_done_)) {
2667 if (strcmp(descriptor, "Ljava/lang/String;") == 0) {
2668 klass->SetStringClass();
2672 ObjectLock<mirror::Class> lock(self, klass);
2673 klass->SetClinitThreadId(self->GetTid());
2674 // Make sure we have a valid empty iftable even if there are errors.
2675 klass->SetIfTable(GetClassRoot(kJavaLangObject)->GetIfTable());
2677 // Add the newly loaded class to the loaded classes table.
2678 ObjPtr<mirror::Class> existing = InsertClass(descriptor, klass.Get(), hash);
2679 if (existing != nullptr) {
2680 // We failed to insert because we raced with another thread. Calling EnsureResolved may cause
2681 // this thread to block.
2682 return EnsureResolved(self, descriptor, existing);
2685 // Load the fields and other things after we are inserted in the table. This is so that we don't
2686 // end up allocating unfree-able linear alloc resources and then lose the race condition. The
2687 // other reason is that the field roots are only visited from the class table. So we need to be
2688 // inserted before we allocate / fill in these fields.
2689 LoadClass(self, *new_dex_file, *new_class_def, klass);
2690 if (self->IsExceptionPending()) {
2691 VLOG(class_linker) << self->GetException()->Dump();
2692 // An exception occured during load, set status to erroneous while holding klass' lock in case
2693 // notification is necessary.
2694 if (!klass->IsErroneous()) {
2695 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorUnresolved, self);
2700 // Finish loading (if necessary) by finding parents
2701 CHECK(!klass->IsLoaded());
2702 if (!LoadSuperAndInterfaces(klass, *new_dex_file)) {
2704 if (!klass->IsErroneous()) {
2705 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorUnresolved, self);
2709 CHECK(klass->IsLoaded());
2711 // At this point the class is loaded. Publish a ClassLoad even.
2712 // Note: this may be a temporary class. It is a listener's responsibility to handle this.
2713 Runtime::Current()->GetRuntimeCallbacks()->ClassLoad(klass);
2715 // Link the class (if necessary)
2716 CHECK(!klass->IsResolved());
2717 // TODO: Use fast jobjects?
2718 auto interfaces = hs.NewHandle<mirror::ObjectArray<mirror::Class>>(nullptr);
2720 MutableHandle<mirror::Class> h_new_class = hs.NewHandle<mirror::Class>(nullptr);
2721 if (!LinkClass(self, descriptor, klass, interfaces, &h_new_class)) {
2723 if (!klass->IsErroneous()) {
2724 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorUnresolved, self);
2728 self->AssertNoPendingException();
2729 CHECK(h_new_class.Get() != nullptr) << descriptor;
2730 CHECK(h_new_class->IsResolved() && !h_new_class->IsErroneousResolved()) << descriptor;
2732 // Instrumentation may have updated entrypoints for all methods of all
2733 // classes. However it could not update methods of this class while we
2734 // were loading it. Now the class is resolved, we can update entrypoints
2735 // as required by instrumentation.
2736 if (Runtime::Current()->GetInstrumentation()->AreExitStubsInstalled()) {
2737 // We must be in the kRunnable state to prevent instrumentation from
2738 // suspending all threads to update entrypoints while we are doing it
2740 DCHECK_EQ(self->GetState(), kRunnable);
2741 Runtime::Current()->GetInstrumentation()->InstallStubsForClass(h_new_class.Get());
2745 * We send CLASS_PREPARE events to the debugger from here. The
2746 * definition of "preparation" is creating the static fields for a
2747 * class and initializing them to the standard default values, but not
2748 * executing any code (that comes later, during "initialization").
2750 * We did the static preparation in LinkClass.
2752 * The class has been prepared and resolved but possibly not yet verified
2755 Runtime::Current()->GetRuntimeCallbacks()->ClassPrepare(klass, h_new_class);
2757 // Notify native debugger of the new class and its layout.
2758 jit::Jit::NewTypeLoadedIfUsingJit(h_new_class.Get());
2760 return h_new_class.Get();
2763 uint32_t ClassLinker::SizeOfClassWithoutEmbeddedTables(const DexFile& dex_file,
2764 const DexFile::ClassDef& dex_class_def) {
2765 const uint8_t* class_data = dex_file.GetClassData(dex_class_def);
2771 if (class_data != nullptr) {
2772 // We allow duplicate definitions of the same field in a class_data_item
2773 // but ignore the repeated indexes here, b/21868015.
2774 uint32_t last_field_idx = DexFile::kDexNoIndex;
2775 for (ClassDataItemIterator it(dex_file, class_data); it.HasNextStaticField(); it.Next()) {
2776 uint32_t field_idx = it.GetMemberIndex();
2777 // Ordering enforced by DexFileVerifier.
2778 DCHECK(last_field_idx == DexFile::kDexNoIndex || last_field_idx <= field_idx);
2779 if (UNLIKELY(field_idx == last_field_idx)) {
2782 last_field_idx = field_idx;
2783 const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx);
2784 const char* descriptor = dex_file.GetFieldTypeDescriptor(field_id);
2785 char c = descriptor[0];
2808 LOG(FATAL) << "Unknown descriptor: " << c;
2813 return mirror::Class::ComputeClassSize(false,
2820 image_pointer_size_);
2823 // Special case to get oat code without overwriting a trampoline.
2824 const void* ClassLinker::GetQuickOatCodeFor(ArtMethod* method) {
2825 CHECK(method->IsInvokable()) << method->PrettyMethod();
2826 if (method->IsProxyMethod()) {
2827 return GetQuickProxyInvokeHandler();
2829 auto* code = method->GetOatMethodQuickCode(GetImagePointerSize());
2830 if (code != nullptr) {
2833 if (method->IsNative()) {
2834 // No code and native? Use generic trampoline.
2835 return GetQuickGenericJniStub();
2837 return GetQuickToInterpreterBridge();
2840 bool ClassLinker::ShouldUseInterpreterEntrypoint(ArtMethod* method, const void* quick_code) {
2841 if (UNLIKELY(method->IsNative() || method->IsProxyMethod())) {
2845 if (quick_code == nullptr) {
2849 Runtime* runtime = Runtime::Current();
2850 instrumentation::Instrumentation* instr = runtime->GetInstrumentation();
2851 if (instr->InterpretOnly()) {
2855 if (runtime->GetClassLinker()->IsQuickToInterpreterBridge(quick_code)) {
2856 // Doing this check avoids doing compiled/interpreter transitions.
2860 if (Dbg::IsForcedInterpreterNeededForCalling(Thread::Current(), method)) {
2861 // Force the use of interpreter when it is required by the debugger.
2865 if (runtime->IsFullyDeoptable()) {
2866 // We need to be able to deoptimize at any time so we should always just ignore precompiled
2867 // code and go to the interpreter assuming we don't already have jitted code.
2868 jit::Jit* jit = Runtime::Current()->GetJit();
2869 return (jit == nullptr) || !jit->GetCodeCache()->ContainsPc(quick_code);
2872 if (runtime->IsNativeDebuggable()) {
2873 DCHECK(runtime->UseJitCompilation() && runtime->GetJit()->JitAtFirstUse());
2874 // If we are doing native debugging, ignore application's AOT code,
2875 // since we want to JIT it with extra stackmaps for native debugging.
2876 // On the other hand, keep all AOT code from the boot image, since the
2877 // blocking JIT would results in non-negligible performance impact.
2878 return !runtime->GetHeap()->IsInBootImageOatFile(quick_code);
2881 if (Dbg::IsDebuggerActive()) {
2882 // Boot image classes may be AOT-compiled as non-debuggable.
2883 // This is not suitable for the Java debugger, so ignore the AOT code.
2884 return runtime->GetHeap()->IsInBootImageOatFile(quick_code);
2890 void ClassLinker::FixupStaticTrampolines(ObjPtr<mirror::Class> klass) {
2891 DCHECK(klass->IsInitialized()) << klass->PrettyDescriptor();
2892 if (klass->NumDirectMethods() == 0) {
2893 return; // No direct methods => no static methods.
2895 Runtime* runtime = Runtime::Current();
2896 if (!runtime->IsStarted()) {
2897 if (runtime->IsAotCompiler() || runtime->GetHeap()->HasBootImageSpace()) {
2898 return; // OAT file unavailable.
2902 const DexFile& dex_file = klass->GetDexFile();
2903 const DexFile::ClassDef* dex_class_def = klass->GetClassDef();
2904 CHECK(dex_class_def != nullptr);
2905 const uint8_t* class_data = dex_file.GetClassData(*dex_class_def);
2906 // There should always be class data if there were direct methods.
2907 CHECK(class_data != nullptr) << klass->PrettyDescriptor();
2908 ClassDataItemIterator it(dex_file, class_data);
2910 while (it.HasNextStaticField()) {
2913 while (it.HasNextInstanceField()) {
2917 OatFile::OatClass oat_class = OatFile::FindOatClass(dex_file,
2918 klass->GetDexClassDefIndex(),
2920 // Link the code of methods skipped by LinkCode.
2921 for (size_t method_index = 0; it.HasNextDirectMethod(); ++method_index, it.Next()) {
2922 ArtMethod* method = klass->GetDirectMethod(method_index, image_pointer_size_);
2923 if (!method->IsStatic()) {
2924 // Only update static methods.
2927 const void* quick_code = nullptr;
2928 if (has_oat_class) {
2929 OatFile::OatMethod oat_method = oat_class.GetOatMethod(method_index);
2930 quick_code = oat_method.GetQuickCode();
2932 // Check whether the method is native, in which case it's generic JNI.
2933 if (quick_code == nullptr && method->IsNative()) {
2934 quick_code = GetQuickGenericJniStub();
2935 } else if (ShouldUseInterpreterEntrypoint(method, quick_code)) {
2936 // Use interpreter entry point.
2937 quick_code = GetQuickToInterpreterBridge();
2939 runtime->GetInstrumentation()->UpdateMethodsCode(method, quick_code);
2941 // Ignore virtual methods on the iterator.
2944 // Does anything needed to make sure that the compiler will not generate a direct invoke to this
2945 // method. Should only be called on non-invokable methods.
2946 inline void EnsureThrowsInvocationError(ClassLinker* class_linker, ArtMethod* method) {
2947 DCHECK(method != nullptr);
2948 DCHECK(!method->IsInvokable());
2949 method->SetEntryPointFromQuickCompiledCodePtrSize(
2950 class_linker->GetQuickToInterpreterBridgeTrampoline(),
2951 class_linker->GetImagePointerSize());
2954 static void LinkCode(ClassLinker* class_linker,
2956 const OatFile::OatClass* oat_class,
2957 uint32_t class_def_method_index) REQUIRES_SHARED(Locks::mutator_lock_) {
2958 Runtime* const runtime = Runtime::Current();
2959 if (runtime->IsAotCompiler()) {
2960 // The following code only applies to a non-compiler runtime.
2963 // Method shouldn't have already been linked.
2964 DCHECK(method->GetEntryPointFromQuickCompiledCode() == nullptr);
2965 if (oat_class != nullptr) {
2966 // Every kind of method should at least get an invoke stub from the oat_method.
2967 // non-abstract methods also get their code pointers.
2968 const OatFile::OatMethod oat_method = oat_class->GetOatMethod(class_def_method_index);
2969 oat_method.LinkMethod(method);
2972 // Install entry point from interpreter.
2973 const void* quick_code = method->GetEntryPointFromQuickCompiledCode();
2974 bool enter_interpreter = class_linker->ShouldUseInterpreterEntrypoint(method, quick_code);
2976 if (!method->IsInvokable()) {
2977 EnsureThrowsInvocationError(class_linker, method);
2981 if (method->IsStatic() && !method->IsConstructor()) {
2982 // For static methods excluding the class initializer, install the trampoline.
2983 // It will be replaced by the proper entry point by ClassLinker::FixupStaticTrampolines
2984 // after initializing class (see ClassLinker::InitializeClass method).
2985 method->SetEntryPointFromQuickCompiledCode(GetQuickResolutionStub());
2986 } else if (quick_code == nullptr && method->IsNative()) {
2987 method->SetEntryPointFromQuickCompiledCode(GetQuickGenericJniStub());
2988 } else if (enter_interpreter) {
2989 // Set entry point from compiled code if there's no code or in interpreter only mode.
2990 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge());
2993 if (method->IsNative()) {
2994 // Unregistering restores the dlsym lookup stub.
2995 method->UnregisterNative();
2997 if (enter_interpreter || quick_code == nullptr) {
2998 // We have a native method here without code. Then it should have either the generic JNI
2999 // trampoline as entrypoint (non-static), or the resolution trampoline (static).
3000 // TODO: this doesn't handle all the cases where trampolines may be installed.
3001 const void* entry_point = method->GetEntryPointFromQuickCompiledCode();
3002 DCHECK(class_linker->IsQuickGenericJniStub(entry_point) ||
3003 class_linker->IsQuickResolutionStub(entry_point));
3008 void ClassLinker::SetupClass(const DexFile& dex_file,
3009 const DexFile::ClassDef& dex_class_def,
3010 Handle<mirror::Class> klass,
3011 ObjPtr<mirror::ClassLoader> class_loader) {
3012 CHECK(klass.Get() != nullptr);
3013 CHECK(klass->GetDexCache() != nullptr);
3014 CHECK_EQ(mirror::Class::kStatusNotReady, klass->GetStatus());
3015 const char* descriptor = dex_file.GetClassDescriptor(dex_class_def);
3016 CHECK(descriptor != nullptr);
3018 klass->SetClass(GetClassRoot(kJavaLangClass));
3019 uint32_t access_flags = dex_class_def.GetJavaAccessFlags();
3020 CHECK_EQ(access_flags & ~kAccJavaFlagsMask, 0U);
3021 klass->SetAccessFlags(access_flags);
3022 klass->SetClassLoader(class_loader);
3023 DCHECK_EQ(klass->GetPrimitiveType(), Primitive::kPrimNot);
3024 mirror::Class::SetStatus(klass, mirror::Class::kStatusIdx, nullptr);
3026 klass->SetDexClassDefIndex(dex_file.GetIndexForClassDef(dex_class_def));
3027 klass->SetDexTypeIndex(dex_class_def.class_idx_);
3030 void ClassLinker::LoadClass(Thread* self,
3031 const DexFile& dex_file,
3032 const DexFile::ClassDef& dex_class_def,
3033 Handle<mirror::Class> klass) {
3034 const uint8_t* class_data = dex_file.GetClassData(dex_class_def);
3035 if (class_data == nullptr) {
3036 return; // no fields or methods - for example a marker interface
3038 LoadClassMembers(self, dex_file, class_data, klass);
3041 LengthPrefixedArray<ArtField>* ClassLinker::AllocArtFieldArray(Thread* self,
3042 LinearAlloc* allocator,
3047 // If the ArtField alignment changes, review all uses of LengthPrefixedArray<ArtField>.
3048 static_assert(alignof(ArtField) == 4, "ArtField alignment is expected to be 4.");
3049 size_t storage_size = LengthPrefixedArray<ArtField>::ComputeSize(length);
3050 void* array_storage = allocator->Alloc(self, storage_size);
3051 auto* ret = new(array_storage) LengthPrefixedArray<ArtField>(length);
3052 CHECK(ret != nullptr);
3053 std::uninitialized_fill_n(&ret->At(0), length, ArtField());
3057 LengthPrefixedArray<ArtMethod>* ClassLinker::AllocArtMethodArray(Thread* self,
3058 LinearAlloc* allocator,
3063 const size_t method_alignment = ArtMethod::Alignment(image_pointer_size_);
3064 const size_t method_size = ArtMethod::Size(image_pointer_size_);
3065 const size_t storage_size =
3066 LengthPrefixedArray<ArtMethod>::ComputeSize(length, method_size, method_alignment);
3067 void* array_storage = allocator->Alloc(self, storage_size);
3068 auto* ret = new (array_storage) LengthPrefixedArray<ArtMethod>(length);
3069 CHECK(ret != nullptr);
3070 for (size_t i = 0; i < length; ++i) {
3071 new(reinterpret_cast<void*>(&ret->At(i, method_size, method_alignment))) ArtMethod;
3076 LinearAlloc* ClassLinker::GetAllocatorForClassLoader(ObjPtr<mirror::ClassLoader> class_loader) {
3077 if (class_loader == nullptr) {
3078 return Runtime::Current()->GetLinearAlloc();
3080 LinearAlloc* allocator = class_loader->GetAllocator();
3081 DCHECK(allocator != nullptr);
3085 LinearAlloc* ClassLinker::GetOrCreateAllocatorForClassLoader(ObjPtr<mirror::ClassLoader> class_loader) {
3086 if (class_loader == nullptr) {
3087 return Runtime::Current()->GetLinearAlloc();
3089 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_);
3090 LinearAlloc* allocator = class_loader->GetAllocator();
3091 if (allocator == nullptr) {
3092 RegisterClassLoader(class_loader);
3093 allocator = class_loader->GetAllocator();
3094 CHECK(allocator != nullptr);
3099 void ClassLinker::LoadClassMembers(Thread* self,
3100 const DexFile& dex_file,
3101 const uint8_t* class_data,
3102 Handle<mirror::Class> klass) {
3104 // Note: We cannot have thread suspension until the field and method arrays are setup or else
3105 // Class::VisitFieldRoots may miss some fields or methods.
3106 ScopedAssertNoThreadSuspension nts(__FUNCTION__);
3107 // Load static fields.
3108 // We allow duplicate definitions of the same field in a class_data_item
3109 // but ignore the repeated indexes here, b/21868015.
3110 LinearAlloc* const allocator = GetAllocatorForClassLoader(klass->GetClassLoader());
3111 ClassDataItemIterator it(dex_file, class_data);
3112 LengthPrefixedArray<ArtField>* sfields = AllocArtFieldArray(self,
3114 it.NumStaticFields());
3115 size_t num_sfields = 0;
3116 uint32_t last_field_idx = 0u;
3117 for (; it.HasNextStaticField(); it.Next()) {
3118 uint32_t field_idx = it.GetMemberIndex();
3119 DCHECK_GE(field_idx, last_field_idx); // Ordering enforced by DexFileVerifier.
3120 if (num_sfields == 0 || LIKELY(field_idx > last_field_idx)) {
3121 DCHECK_LT(num_sfields, it.NumStaticFields());
3122 LoadField(it, klass, &sfields->At(num_sfields));
3124 last_field_idx = field_idx;
3127 // Load instance fields.
3128 LengthPrefixedArray<ArtField>* ifields = AllocArtFieldArray(self,
3130 it.NumInstanceFields());
3131 size_t num_ifields = 0u;
3132 last_field_idx = 0u;
3133 for (; it.HasNextInstanceField(); it.Next()) {
3134 uint32_t field_idx = it.GetMemberIndex();
3135 DCHECK_GE(field_idx, last_field_idx); // Ordering enforced by DexFileVerifier.
3136 if (num_ifields == 0 || LIKELY(field_idx > last_field_idx)) {
3137 DCHECK_LT(num_ifields, it.NumInstanceFields());
3138 LoadField(it, klass, &ifields->At(num_ifields));
3140 last_field_idx = field_idx;
3143 if (UNLIKELY(num_sfields != it.NumStaticFields()) ||
3144 UNLIKELY(num_ifields != it.NumInstanceFields())) {
3145 LOG(WARNING) << "Duplicate fields in class " << klass->PrettyDescriptor()
3146 << " (unique static fields: " << num_sfields << "/" << it.NumStaticFields()
3147 << ", unique instance fields: " << num_ifields << "/" << it.NumInstanceFields() << ")";
3148 // NOTE: Not shrinking the over-allocated sfields/ifields, just setting size.
3149 if (sfields != nullptr) {
3150 sfields->SetSize(num_sfields);
3152 if (ifields != nullptr) {
3153 ifields->SetSize(num_ifields);
3156 // Set the field arrays.
3157 klass->SetSFieldsPtr(sfields);
3158 DCHECK_EQ(klass->NumStaticFields(), num_sfields);
3159 klass->SetIFieldsPtr(ifields);
3160 DCHECK_EQ(klass->NumInstanceFields(), num_ifields);
3162 bool has_oat_class = false;
3163 const OatFile::OatClass oat_class =
3164 (Runtime::Current()->IsStarted() && !Runtime::Current()->IsAotCompiler())
3165 ? OatFile::FindOatClass(dex_file, klass->GetDexClassDefIndex(), &has_oat_class)
3166 : OatFile::OatClass::Invalid();
3167 const OatFile::OatClass* oat_class_ptr = has_oat_class ? &oat_class : nullptr;
3168 klass->SetMethodsPtr(
3169 AllocArtMethodArray(self, allocator, it.NumDirectMethods() + it.NumVirtualMethods()),
3170 it.NumDirectMethods(),
3171 it.NumVirtualMethods());
3172 size_t class_def_method_index = 0;
3173 uint32_t last_dex_method_index = DexFile::kDexNoIndex;
3174 size_t last_class_def_method_index = 0;
3175 // TODO These should really use the iterators.
3176 for (size_t i = 0; it.HasNextDirectMethod(); i++, it.Next()) {
3177 ArtMethod* method = klass->GetDirectMethodUnchecked(i, image_pointer_size_);
3178 LoadMethod(dex_file, it, klass, method);
3179 LinkCode(this, method, oat_class_ptr, class_def_method_index);
3180 uint32_t it_method_index = it.GetMemberIndex();
3181 if (last_dex_method_index == it_method_index) {
3183 method->SetMethodIndex(last_class_def_method_index);
3185 method->SetMethodIndex(class_def_method_index);
3186 last_dex_method_index = it_method_index;
3187 last_class_def_method_index = class_def_method_index;
3189 class_def_method_index++;
3191 for (size_t i = 0; it.HasNextVirtualMethod(); i++, it.Next()) {
3192 ArtMethod* method = klass->GetVirtualMethodUnchecked(i, image_pointer_size_);
3193 LoadMethod(dex_file, it, klass, method);
3194 DCHECK_EQ(class_def_method_index, it.NumDirectMethods() + i);
3195 LinkCode(this, method, oat_class_ptr, class_def_method_index);
3196 class_def_method_index++;
3198 DCHECK(!it.HasNext());
3200 // Ensure that the card is marked so that remembered sets pick up native roots.
3201 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(klass.Get());
3202 self->AllowThreadSuspension();
3205 void ClassLinker::LoadField(const ClassDataItemIterator& it,
3206 Handle<mirror::Class> klass,
3208 const uint32_t field_idx = it.GetMemberIndex();
3209 dst->SetDexFieldIndex(field_idx);
3210 dst->SetDeclaringClass(klass.Get());
3211 dst->SetAccessFlags(it.GetFieldAccessFlags());
3214 void ClassLinker::LoadMethod(const DexFile& dex_file,
3215 const ClassDataItemIterator& it,
3216 Handle<mirror::Class> klass,
3218 uint32_t dex_method_idx = it.GetMemberIndex();
3219 const DexFile::MethodId& method_id = dex_file.GetMethodId(dex_method_idx);
3220 const char* method_name = dex_file.StringDataByIdx(method_id.name_idx_);
3222 ScopedAssertNoThreadSuspension ants("LoadMethod");
3223 dst->SetDexMethodIndex(dex_method_idx);
3224 dst->SetDeclaringClass(klass.Get());
3225 dst->SetCodeItemOffset(it.GetMethodCodeItemOffset());
3227 dst->SetDexCacheResolvedMethods(klass->GetDexCache()->GetResolvedMethods(), image_pointer_size_);
3229 uint32_t access_flags = it.GetMethodAccessFlags();
3231 if (UNLIKELY(strcmp("finalize", method_name) == 0)) {
3232 // Set finalizable flag on declaring class.
3233 if (strcmp("V", dex_file.GetShorty(method_id.proto_idx_)) == 0) {
3234 // Void return type.
3235 if (klass->GetClassLoader() != nullptr) { // All non-boot finalizer methods are flagged.
3236 klass->SetFinalizable();
3239 const char* klass_descriptor = klass->GetDescriptor(&temp);
3240 // The Enum class declares a "final" finalize() method to prevent subclasses from
3241 // introducing a finalizer. We don't want to set the finalizable flag for Enum or its
3242 // subclasses, so we exclude it here.
3243 // We also want to avoid setting the flag on Object, where we know that finalize() is
3245 if (strcmp(klass_descriptor, "Ljava/lang/Object;") != 0 &&
3246 strcmp(klass_descriptor, "Ljava/lang/Enum;") != 0) {
3247 klass->SetFinalizable();
3251 } else if (method_name[0] == '<') {
3252 // Fix broken access flags for initializers. Bug 11157540.
3253 bool is_init = (strcmp("<init>", method_name) == 0);
3254 bool is_clinit = !is_init && (strcmp("<clinit>", method_name) == 0);
3255 if (UNLIKELY(!is_init && !is_clinit)) {
3256 LOG(WARNING) << "Unexpected '<' at start of method name " << method_name;
3258 if (UNLIKELY((access_flags & kAccConstructor) == 0)) {
3259 LOG(WARNING) << method_name << " didn't have expected constructor access flag in class "
3260 << klass->PrettyDescriptor() << " in dex file " << dex_file.GetLocation();
3261 access_flags |= kAccConstructor;
3265 dst->SetAccessFlags(access_flags);
3268 void ClassLinker::AppendToBootClassPath(Thread* self, const DexFile& dex_file) {
3269 StackHandleScope<1> hs(self);
3270 Handle<mirror::DexCache> dex_cache(hs.NewHandle(AllocAndInitializeDexCache(
3273 Runtime::Current()->GetLinearAlloc())));
3274 CHECK(dex_cache.Get() != nullptr) << "Failed to allocate dex cache for "
3275 << dex_file.GetLocation();
3276 AppendToBootClassPath(dex_file, dex_cache);
3279 void ClassLinker::AppendToBootClassPath(const DexFile& dex_file,
3280 Handle<mirror::DexCache> dex_cache) {
3281 CHECK(dex_cache.Get() != nullptr) << dex_file.GetLocation();
3282 boot_class_path_.push_back(&dex_file);
3283 RegisterDexFile(dex_file, dex_cache);
3286 void ClassLinker::RegisterDexFileLocked(const DexFile& dex_file,
3287 Handle<mirror::DexCache> dex_cache) {
3288 Thread* const self = Thread::Current();
3289 Locks::dex_lock_->AssertExclusiveHeld(self);
3290 CHECK(dex_cache.Get() != nullptr) << dex_file.GetLocation();
3291 // For app images, the dex cache location may be a suffix of the dex file location since the
3292 // dex file location is an absolute path.
3293 const std::string dex_cache_location = dex_cache->GetLocation()->ToModifiedUtf8();
3294 const size_t dex_cache_length = dex_cache_location.length();
3295 CHECK_GT(dex_cache_length, 0u) << dex_file.GetLocation();
3296 std::string dex_file_location = dex_file.GetLocation();
3297 CHECK_GE(dex_file_location.length(), dex_cache_length)
3298 << dex_cache_location << " " << dex_file.GetLocation();
3300 const std::string dex_file_suffix = dex_file_location.substr(
3301 dex_file_location.length() - dex_cache_length,
3303 // Example dex_cache location is SettingsProvider.apk and
3304 // dex file location is /system/priv-app/SettingsProvider/SettingsProvider.apk
3305 CHECK_EQ(dex_cache_location, dex_file_suffix);
3306 // Clean up pass to remove null dex caches.
3307 // Null dex caches can occur due to class unloading and we are lazily removing null entries.
3308 JavaVMExt* const vm = self->GetJniEnv()->vm;
3309 for (auto it = dex_caches_.begin(); it != dex_caches_.end(); ) {
3310 DexCacheData data = *it;
3311 if (self->IsJWeakCleared(data.weak_root)) {
3312 vm->DeleteWeakGlobalRef(self, data.weak_root);
3313 it = dex_caches_.erase(it);
3318 jweak dex_cache_jweak = vm->AddWeakGlobalRef(self, dex_cache.Get());
3319 dex_cache->SetDexFile(&dex_file);
3321 data.weak_root = dex_cache_jweak;
3322 data.dex_file = dex_cache->GetDexFile();
3323 data.resolved_methods = dex_cache->GetResolvedMethods();
3324 dex_caches_.push_back(data);
3327 mirror::DexCache* ClassLinker::RegisterDexFile(const DexFile& dex_file,
3328 ObjPtr<mirror::ClassLoader> class_loader) {
3329 Thread* self = Thread::Current();
3331 ReaderMutexLock mu(self, *Locks::dex_lock_);
3332 ObjPtr<mirror::DexCache> dex_cache = FindDexCacheLocked(self, dex_file, true);
3333 if (dex_cache != nullptr) {
3334 // TODO: Check if the dex file was registered with the same class loader. Bug: 34193123
3335 return dex_cache.Ptr();
3338 LinearAlloc* const linear_alloc = GetOrCreateAllocatorForClassLoader(class_loader);
3339 DCHECK(linear_alloc != nullptr);
3342 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_);
3343 table = InsertClassTableForClassLoader(class_loader);
3345 // Don't alloc while holding the lock, since allocation may need to
3346 // suspend all threads and another thread may need the dex_lock_ to
3347 // get to a suspend point.
3348 StackHandleScope<2> hs(self);
3349 ObjPtr<mirror::String> location;
3350 Handle<mirror::DexCache> h_dex_cache(hs.NewHandle(AllocDexCache(/*out*/&location,
3353 Handle<mirror::String> h_location(hs.NewHandle(location));
3355 WriterMutexLock mu(self, *Locks::dex_lock_);
3356 ObjPtr<mirror::DexCache> dex_cache = FindDexCacheLocked(self, dex_file, true);
3357 if (dex_cache != nullptr) {
3358 // Another thread managed to initialize the dex cache faster, so use that DexCache.
3359 // If this thread encountered OOME, ignore it.
3360 DCHECK_EQ(h_dex_cache.Get() == nullptr, self->IsExceptionPending());
3361 self->ClearException();
3362 return dex_cache.Ptr();
3364 if (h_dex_cache.Get() == nullptr) {
3365 self->AssertPendingOOMException();
3368 // Do InitializeDexCache while holding dex lock to make sure two threads don't call it at the
3369 // same time with the same dex cache. Since the .bss is shared this can cause failing DCHECK
3370 // that the arrays are null.
3371 mirror::DexCache::InitializeDexCache(self,
3376 image_pointer_size_);
3377 RegisterDexFileLocked(dex_file, h_dex_cache);
3379 table->InsertStrongRoot(h_dex_cache.Get());
3380 return h_dex_cache.Get();
3383 void ClassLinker::RegisterDexFile(const DexFile& dex_file,
3384 Handle<mirror::DexCache> dex_cache) {
3385 WriterMutexLock mu(Thread::Current(), *Locks::dex_lock_);
3386 RegisterDexFileLocked(dex_file, dex_cache);
3389 mirror::DexCache* ClassLinker::FindDexCache(Thread* self,
3390 const DexFile& dex_file,
3391 bool allow_failure) {
3392 ReaderMutexLock mu(self, *Locks::dex_lock_);
3393 return FindDexCacheLocked(self, dex_file, allow_failure);
3396 mirror::DexCache* ClassLinker::FindDexCacheLocked(Thread* self,
3397 const DexFile& dex_file,
3398 bool allow_failure) {
3399 // Search assuming unique-ness of dex file.
3400 for (const DexCacheData& data : dex_caches_) {
3401 // Avoid decoding (and read barriers) other unrelated dex caches.
3402 if (data.dex_file == &dex_file) {
3403 ObjPtr<mirror::DexCache> dex_cache =
3404 ObjPtr<mirror::DexCache>::DownCast(self->DecodeJObject(data.weak_root));
3405 if (dex_cache != nullptr) {
3406 return dex_cache.Ptr();
3411 if (allow_failure) {
3414 std::string location(dex_file.GetLocation());
3415 // Failure, dump diagnostic and abort.
3416 for (const DexCacheData& data : dex_caches_) {
3417 ObjPtr<mirror::DexCache> dex_cache =
3418 ObjPtr<mirror::DexCache>::DownCast(self->DecodeJObject(data.weak_root));
3419 if (dex_cache != nullptr) {
3420 LOG(ERROR) << "Registered dex file " << dex_cache->GetDexFile()->GetLocation();
3423 LOG(FATAL) << "Failed to find DexCache for DexFile " << location;
3427 void ClassLinker::FixupDexCaches(ArtMethod* resolution_method) {
3428 Thread* const self = Thread::Current();
3429 ReaderMutexLock mu(self, *Locks::dex_lock_);
3430 for (const DexCacheData& data : dex_caches_) {
3431 if (!self->IsJWeakCleared(data.weak_root)) {
3432 ObjPtr<mirror::DexCache> dex_cache = ObjPtr<mirror::DexCache>::DownCast(
3433 self->DecodeJObject(data.weak_root));
3434 if (dex_cache != nullptr) {
3435 dex_cache->Fixup(resolution_method, image_pointer_size_);
3441 mirror::Class* ClassLinker::CreatePrimitiveClass(Thread* self, Primitive::Type type) {
3442 ObjPtr<mirror::Class> klass =
3443 AllocClass(self, mirror::Class::PrimitiveClassSize(image_pointer_size_));
3444 if (UNLIKELY(klass == nullptr)) {
3445 self->AssertPendingOOMException();
3448 return InitializePrimitiveClass(klass, type);
3451 mirror::Class* ClassLinker::InitializePrimitiveClass(ObjPtr<mirror::Class> primitive_class,
3452 Primitive::Type type) {
3453 CHECK(primitive_class != nullptr);
3454 // Must hold lock on object when initializing.
3455 Thread* self = Thread::Current();
3456 StackHandleScope<1> hs(self);
3457 Handle<mirror::Class> h_class(hs.NewHandle(primitive_class));
3458 ObjectLock<mirror::Class> lock(self, h_class);
3459 h_class->SetAccessFlags(kAccPublic | kAccFinal | kAccAbstract);
3460 h_class->SetPrimitiveType(type);
3461 h_class->SetIfTable(GetClassRoot(kJavaLangObject)->GetIfTable());
3462 mirror::Class::SetStatus(h_class, mirror::Class::kStatusInitialized, self);
3463 const char* descriptor = Primitive::Descriptor(type);
3464 ObjPtr<mirror::Class> existing = InsertClass(descriptor,
3466 ComputeModifiedUtf8Hash(descriptor));
3467 CHECK(existing == nullptr) << "InitPrimitiveClass(" << type << ") failed";
3468 return h_class.Get();
3471 // Create an array class (i.e. the class object for the array, not the
3472 // array itself). "descriptor" looks like "[C" or "[[[[B" or
3473 // "[Ljava/lang/String;".
3475 // If "descriptor" refers to an array of primitives, look up the
3476 // primitive type's internally-generated class object.
3478 // "class_loader" is the class loader of the class that's referring to
3479 // us. It's used to ensure that we're looking for the element type in
3480 // the right context. It does NOT become the class loader for the
3481 // array class; that always comes from the base element class.
3483 // Returns null with an exception raised on failure.
3484 mirror::Class* ClassLinker::CreateArrayClass(Thread* self, const char* descriptor, size_t hash,
3485 Handle<mirror::ClassLoader> class_loader) {
3486 // Identify the underlying component type
3487 CHECK_EQ('[', descriptor[0]);
3488 StackHandleScope<2> hs(self);
3489 MutableHandle<mirror::Class> component_type(hs.NewHandle(FindClass(self, descriptor + 1,
3491 if (component_type.Get() == nullptr) {
3492 DCHECK(self->IsExceptionPending());
3493 // We need to accept erroneous classes as component types.
3494 const size_t component_hash = ComputeModifiedUtf8Hash(descriptor + 1);
3495 component_type.Assign(LookupClass(self, descriptor + 1, component_hash, class_loader.Get()));
3496 if (component_type.Get() == nullptr) {
3497 DCHECK(self->IsExceptionPending());
3500 self->ClearException();
3503 if (UNLIKELY(component_type->IsPrimitiveVoid())) {
3504 ThrowNoClassDefFoundError("Attempt to create array of void primitive type");
3507 // See if the component type is already loaded. Array classes are
3508 // always associated with the class loader of their underlying
3509 // element type -- an array of Strings goes with the loader for
3510 // java/lang/String -- so we need to look for it there. (The
3511 // caller should have checked for the existence of the class
3512 // before calling here, but they did so with *their* class loader,
3513 // not the component type's loader.)
3515 // If we find it, the caller adds "loader" to the class' initiating
3516 // loader list, which should prevent us from going through this again.
3518 // This call is unnecessary if "loader" and "component_type->GetClassLoader()"
3519 // are the same, because our caller (FindClass) just did the
3520 // lookup. (Even if we get this wrong we still have correct behavior,
3521 // because we effectively do this lookup again when we add the new
3522 // class to the hash table --- necessary because of possible races with
3524 if (class_loader.Get() != component_type->GetClassLoader()) {
3525 ObjPtr<mirror::Class> new_class =
3526 LookupClass(self, descriptor, hash, component_type->GetClassLoader());
3527 if (new_class != nullptr) {
3528 return new_class.Ptr();
3532 // Fill out the fields in the Class.
3534 // It is possible to execute some methods against arrays, because
3535 // all arrays are subclasses of java_lang_Object_, so we need to set
3536 // up a vtable. We can just point at the one in java_lang_Object_.
3538 // Array classes are simple enough that we don't need to do a full
3540 auto new_class = hs.NewHandle<mirror::Class>(nullptr);
3541 if (UNLIKELY(!init_done_)) {
3542 // Classes that were hand created, ie not by FindSystemClass
3543 if (strcmp(descriptor, "[Ljava/lang/Class;") == 0) {
3544 new_class.Assign(GetClassRoot(kClassArrayClass));
3545 } else if (strcmp(descriptor, "[Ljava/lang/Object;") == 0) {
3546 new_class.Assign(GetClassRoot(kObjectArrayClass));
3547 } else if (strcmp(descriptor, GetClassRootDescriptor(kJavaLangStringArrayClass)) == 0) {
3548 new_class.Assign(GetClassRoot(kJavaLangStringArrayClass));
3549 } else if (strcmp(descriptor, "[C") == 0) {
3550 new_class.Assign(GetClassRoot(kCharArrayClass));
3551 } else if (strcmp(descriptor, "[I") == 0) {
3552 new_class.Assign(GetClassRoot(kIntArrayClass));
3553 } else if (strcmp(descriptor, "[J") == 0) {
3554 new_class.Assign(GetClassRoot(kLongArrayClass));
3557 if (new_class.Get() == nullptr) {
3558 new_class.Assign(AllocClass(self, mirror::Array::ClassSize(image_pointer_size_)));
3559 if (new_class.Get() == nullptr) {
3560 self->AssertPendingOOMException();
3563 new_class->SetComponentType(component_type.Get());
3565 ObjectLock<mirror::Class> lock(self, new_class); // Must hold lock on object when initializing.
3566 DCHECK(new_class->GetComponentType() != nullptr);
3567 ObjPtr<mirror::Class> java_lang_Object = GetClassRoot(kJavaLangObject);
3568 new_class->SetSuperClass(java_lang_Object);
3569 new_class->SetVTable(java_lang_Object->GetVTable());
3570 new_class->SetPrimitiveType(Primitive::kPrimNot);
3571 new_class->SetClassLoader(component_type->GetClassLoader());
3572 if (component_type->IsPrimitive()) {
3573 new_class->SetClassFlags(mirror::kClassFlagNoReferenceFields);
3575 new_class->SetClassFlags(mirror::kClassFlagObjectArray);
3577 mirror::Class::SetStatus(new_class, mirror::Class::kStatusLoaded, self);
3578 new_class->PopulateEmbeddedVTable(image_pointer_size_);
3579 ImTable* object_imt = java_lang_Object->GetImt(image_pointer_size_);
3580 new_class->SetImt(object_imt, image_pointer_size_);
3581 mirror::Class::SetStatus(new_class, mirror::Class::kStatusInitialized, self);
3582 // don't need to set new_class->SetObjectSize(..)
3583 // because Object::SizeOf delegates to Array::SizeOf
3585 // All arrays have java/lang/Cloneable and java/io/Serializable as
3586 // interfaces. We need to set that up here, so that stuff like
3587 // "instanceof" works right.
3589 // Note: The GC could run during the call to FindSystemClass,
3590 // so we need to make sure the class object is GC-valid while we're in
3591 // there. Do this by clearing the interface list so the GC will just
3592 // think that the entries are null.
3595 // Use the single, global copies of "interfaces" and "iftable"
3596 // (remember not to free them for arrays).
3598 ObjPtr<mirror::IfTable> array_iftable = array_iftable_.Read();
3599 CHECK(array_iftable != nullptr);
3600 new_class->SetIfTable(array_iftable);
3603 // Inherit access flags from the component type.
3604 int access_flags = new_class->GetComponentType()->GetAccessFlags();
3605 // Lose any implementation detail flags; in particular, arrays aren't finalizable.
3606 access_flags &= kAccJavaFlagsMask;
3607 // Arrays can't be used as a superclass or interface, so we want to add "abstract final"
3608 // and remove "interface".
3609 access_flags |= kAccAbstract | kAccFinal;
3610 access_flags &= ~kAccInterface;
3612 new_class->SetAccessFlags(access_flags);
3614 ObjPtr<mirror::Class> existing = InsertClass(descriptor, new_class.Get(), hash);
3615 if (existing == nullptr) {
3616 jit::Jit::NewTypeLoadedIfUsingJit(new_class.Get());
3617 return new_class.Get();
3619 // Another thread must have loaded the class after we
3620 // started but before we finished. Abandon what we've
3623 // (Yes, this happens.)
3625 return existing.Ptr();
3628 mirror::Class* ClassLinker::FindPrimitiveClass(char type) {
3631 return GetClassRoot(kPrimitiveByte);
3633 return GetClassRoot(kPrimitiveChar);
3635 return GetClassRoot(kPrimitiveDouble);
3637 return GetClassRoot(kPrimitiveFloat);
3639 return GetClassRoot(kPrimitiveInt);
3641 return GetClassRoot(kPrimitiveLong);
3643 return GetClassRoot(kPrimitiveShort);
3645 return GetClassRoot(kPrimitiveBoolean);
3647 return GetClassRoot(kPrimitiveVoid);
3651 std::string printable_type(PrintableChar(type));
3652 ThrowNoClassDefFoundError("Not a primitive type: %s", printable_type.c_str());
3656 mirror::Class* ClassLinker::InsertClass(const char* descriptor, ObjPtr<mirror::Class> klass, size_t hash) {
3657 if (VLOG_IS_ON(class_linker)) {
3658 ObjPtr<mirror::DexCache> dex_cache = klass->GetDexCache();
3660 if (dex_cache != nullptr) {
3662 source += dex_cache->GetLocation()->ToModifiedUtf8();
3664 LOG(INFO) << "Loaded class " << descriptor << source;
3667 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_);
3668 ObjPtr<mirror::ClassLoader> const class_loader = klass->GetClassLoader();
3669 ClassTable* const class_table = InsertClassTableForClassLoader(class_loader);
3670 ObjPtr<mirror::Class> existing = class_table->Lookup(descriptor, hash);
3671 if (existing != nullptr) {
3672 return existing.Ptr();
3674 VerifyObject(klass);
3675 class_table->InsertWithHash(klass, hash);
3676 if (class_loader != nullptr) {
3677 // This is necessary because we need to have the card dirtied for remembered sets.
3678 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(class_loader);
3680 if (log_new_roots_) {
3681 new_class_roots_.push_back(GcRoot<mirror::Class>(klass));
3684 if (kIsDebugBuild) {
3685 // Test that copied methods correctly can find their holder.
3686 for (ArtMethod& method : klass->GetCopiedMethods(image_pointer_size_)) {
3687 CHECK_EQ(GetHoldingClassOfCopiedMethod(&method), klass);
3693 void ClassLinker::WriteBarrierForBootOatFileBssRoots(const OatFile* oat_file) {
3694 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_);
3695 DCHECK(!oat_file->GetBssGcRoots().empty()) << oat_file->GetLocation();
3696 if (log_new_roots_ && !ContainsElement(new_bss_roots_boot_oat_files_, oat_file)) {
3697 new_bss_roots_boot_oat_files_.push_back(oat_file);
3701 // TODO This should really be in mirror::Class.
3702 void ClassLinker::UpdateClassMethods(ObjPtr<mirror::Class> klass,
3703 LengthPrefixedArray<ArtMethod>* new_methods) {
3704 klass->SetMethodsPtrUnchecked(new_methods,
3705 klass->NumDirectMethods(),
3706 klass->NumDeclaredVirtualMethods());
3707 // Need to mark the card so that the remembered sets and mod union tables get updated.
3708 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(klass);
3711 mirror::Class* ClassLinker::LookupClass(Thread* self,
3712 const char* descriptor,
3714 ObjPtr<mirror::ClassLoader> class_loader) {
3715 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_);
3716 ClassTable* const class_table = ClassTableForClassLoader(class_loader);
3717 if (class_table != nullptr) {
3718 ObjPtr<mirror::Class> result = class_table->Lookup(descriptor, hash);
3719 if (result != nullptr) {
3720 return result.Ptr();
3726 class MoveClassTableToPreZygoteVisitor : public ClassLoaderVisitor {
3728 explicit MoveClassTableToPreZygoteVisitor() {}
3730 void Visit(ObjPtr<mirror::ClassLoader> class_loader)
3731 REQUIRES(Locks::classlinker_classes_lock_)
3732 REQUIRES_SHARED(Locks::mutator_lock_) OVERRIDE {
3733 ClassTable* const class_table = class_loader->GetClassTable();
3734 if (class_table != nullptr) {
3735 class_table->FreezeSnapshot();
3740 void ClassLinker::MoveClassTableToPreZygote() {
3741 WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_);
3742 boot_class_table_.FreezeSnapshot();
3743 MoveClassTableToPreZygoteVisitor visitor;
3744 VisitClassLoaders(&visitor);
3747 // Look up classes by hash and descriptor and put all matching ones in the result array.
3748 class LookupClassesVisitor : public ClassLoaderVisitor {
3750 LookupClassesVisitor(const char* descriptor,
3752 std::vector<ObjPtr<mirror::Class>>* result)
3753 : descriptor_(descriptor),
3757 void Visit(ObjPtr<mirror::ClassLoader> class_loader)
3758 REQUIRES_SHARED(Locks::classlinker_classes_lock_, Locks::mutator_lock_) OVERRIDE {
3759 ClassTable* const class_table = class_loader->GetClassTable();
3760 ObjPtr<mirror::Class> klass = class_table->Lookup(descriptor_, hash_);
3761 // Add `klass` only if `class_loader` is its defining (not just initiating) class loader.
3762 if (klass != nullptr && klass->GetClassLoader() == class_loader) {
3763 result_->push_back(klass);
3768 const char* const descriptor_;
3770 std::vector<ObjPtr<mirror::Class>>* const result_;
3773 void ClassLinker::LookupClasses(const char* descriptor,
3774 std::vector<ObjPtr<mirror::Class>>& result) {
3776 Thread* const self = Thread::Current();
3777 ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_);
3778 const size_t hash = ComputeModifiedUtf8Hash(descriptor);
3779 ObjPtr<mirror::Class> klass = boot_class_table_.Lookup(descriptor, hash);
3780 if (klass != nullptr) {
3781 DCHECK(klass->GetClassLoader() == nullptr);
3782 result.push_back(klass);
3784 LookupClassesVisitor visitor(descriptor, hash, &result);
3785 VisitClassLoaders(&visitor);
3788 bool ClassLinker::AttemptSupertypeVerification(Thread* self,
3789 Handle<mirror::Class> klass,
3790 Handle<mirror::Class> supertype) {
3791 DCHECK(self != nullptr);
3792 DCHECK(klass.Get() != nullptr);
3793 DCHECK(supertype.Get() != nullptr);
3795 if (!supertype->IsVerified() && !supertype->IsErroneous()) {
3796 VerifyClass(self, supertype);
3798 if (supertype->IsCompileTimeVerified()) {
3799 // Either we are verified or we soft failed and need to retry at runtime.
3802 // If we got this far then we have a hard failure.
3803 std::string error_msg =
3804 StringPrintf("Rejecting class %s that attempts to sub-type erroneous class %s",
3805 klass->PrettyDescriptor().c_str(),
3806 supertype->PrettyDescriptor().c_str());
3807 LOG(WARNING) << error_msg << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8();
3808 StackHandleScope<1> hs(self);
3809 Handle<mirror::Throwable> cause(hs.NewHandle(self->GetException()));
3810 if (cause.Get() != nullptr) {
3811 // Set during VerifyClass call (if at all).
3812 self->ClearException();
3814 // Change into a verify error.
3815 ThrowVerifyError(klass.Get(), "%s", error_msg.c_str());
3816 if (cause.Get() != nullptr) {
3817 self->GetException()->SetCause(cause.Get());
3819 ClassReference ref(klass->GetDexCache()->GetDexFile(), klass->GetDexClassDefIndex());
3820 if (Runtime::Current()->IsAotCompiler()) {
3821 Runtime::Current()->GetCompilerCallbacks()->ClassRejected(ref);
3823 // Need to grab the lock to change status.
3824 ObjectLock<mirror::Class> super_lock(self, klass);
3825 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorResolved, self);
3829 // Ensures that methods have the kAccSkipAccessChecks bit set. We use the
3830 // kAccVerificationAttempted bit on the class access flags to determine whether this has been done
3832 static void EnsureSkipAccessChecksMethods(Handle<mirror::Class> klass, PointerSize pointer_size)
3833 REQUIRES_SHARED(Locks::mutator_lock_) {
3834 if (!klass->WasVerificationAttempted()) {
3835 klass->SetSkipAccessChecksFlagOnAllMethods(pointer_size);
3836 klass->SetVerificationAttempted();
3840 verifier::MethodVerifier::FailureKind ClassLinker::VerifyClass(
3841 Thread* self, Handle<mirror::Class> klass, verifier::HardFailLogMode log_level) {
3843 // TODO: assert that the monitor on the Class is held
3844 ObjectLock<mirror::Class> lock(self, klass);
3846 // Is somebody verifying this now?
3847 mirror::Class::Status old_status = klass->GetStatus();
3848 while (old_status == mirror::Class::kStatusVerifying ||
3849 old_status == mirror::Class::kStatusVerifyingAtRuntime) {
3850 lock.WaitIgnoringInterrupts();
3851 CHECK(klass->IsErroneous() || (klass->GetStatus() > old_status))
3852 << "Class '" << klass->PrettyClass()
3853 << "' performed an illegal verification state transition from " << old_status
3854 << " to " << klass->GetStatus();
3855 old_status = klass->GetStatus();
3858 // The class might already be erroneous, for example at compile time if we attempted to verify
3859 // this class as a parent to another.
3860 if (klass->IsErroneous()) {
3861 ThrowEarlierClassFailure(klass.Get());
3862 return verifier::MethodVerifier::kHardFailure;
3865 // Don't attempt to re-verify if already sufficiently verified.
3866 if (klass->IsVerified()) {
3867 EnsureSkipAccessChecksMethods(klass, image_pointer_size_);
3868 return verifier::MethodVerifier::kNoFailure;
3870 if (klass->IsCompileTimeVerified() && Runtime::Current()->IsAotCompiler()) {
3871 return verifier::MethodVerifier::kNoFailure;
3874 if (klass->GetStatus() == mirror::Class::kStatusResolved) {
3875 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerifying, self);
3877 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime)
3878 << klass->PrettyClass();
3879 CHECK(!Runtime::Current()->IsAotCompiler());
3880 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerifyingAtRuntime, self);
3883 // Skip verification if disabled.
3884 if (!Runtime::Current()->IsVerificationEnabled()) {
3885 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self);
3886 EnsureSkipAccessChecksMethods(klass, image_pointer_size_);
3887 return verifier::MethodVerifier::kNoFailure;
3891 // Verify super class.
3892 StackHandleScope<2> hs(self);
3893 MutableHandle<mirror::Class> supertype(hs.NewHandle(klass->GetSuperClass()));
3894 // If we have a superclass and we get a hard verification failure we can return immediately.
3895 if (supertype.Get() != nullptr && !AttemptSupertypeVerification(self, klass, supertype)) {
3896 CHECK(self->IsExceptionPending()) << "Verification error should be pending.";
3897 return verifier::MethodVerifier::kHardFailure;
3900 // Verify all default super-interfaces.
3902 // (1) Don't bother if the superclass has already had a soft verification failure.
3904 // (2) Interfaces shouldn't bother to do this recursive verification because they cannot cause
3905 // recursive initialization by themselves. This is because when an interface is initialized
3906 // directly it must not initialize its superinterfaces. We are allowed to verify regardless
3907 // but choose not to for an optimization. If the interfaces is being verified due to a class
3908 // initialization (which would need all the default interfaces to be verified) the class code
3909 // will trigger the recursive verification anyway.
3910 if ((supertype.Get() == nullptr || supertype->IsVerified()) // See (1)
3911 && !klass->IsInterface()) { // See (2)
3912 int32_t iftable_count = klass->GetIfTableCount();
3913 MutableHandle<mirror::Class> iface(hs.NewHandle<mirror::Class>(nullptr));
3914 // Loop through all interfaces this class has defined. It doesn't matter the order.
3915 for (int32_t i = 0; i < iftable_count; i++) {
3916 iface.Assign(klass->GetIfTable()->GetInterface(i));
3917 DCHECK(iface.Get() != nullptr);
3918 // We only care if we have default interfaces and can skip if we are already verified...
3919 if (LIKELY(!iface->HasDefaultMethods() || iface->IsVerified())) {
3921 } else if (UNLIKELY(!AttemptSupertypeVerification(self, klass, iface))) {
3922 // We had a hard failure while verifying this interface. Just return immediately.
3923 CHECK(self->IsExceptionPending()) << "Verification error should be pending.";
3924 return verifier::MethodVerifier::kHardFailure;
3925 } else if (UNLIKELY(!iface->IsVerified())) {
3926 // We softly failed to verify the iface. Stop checking and clean up.
3927 // Put the iface into the supertype handle so we know what caused us to fail.
3928 supertype.Assign(iface.Get());
3934 // At this point if verification failed, then supertype is the "first" supertype that failed
3935 // verification (without a specific order). If verification succeeded, then supertype is either
3936 // null or the original superclass of klass and is verified.
3937 DCHECK(supertype.Get() == nullptr ||
3938 supertype.Get() == klass->GetSuperClass() ||
3939 !supertype->IsVerified());
3941 // Try to use verification information from the oat file, otherwise do runtime verification.
3942 const DexFile& dex_file = *klass->GetDexCache()->GetDexFile();
3943 mirror::Class::Status oat_file_class_status(mirror::Class::kStatusNotReady);
3944 bool preverified = VerifyClassUsingOatFile(dex_file, klass.Get(), oat_file_class_status);
3945 // If the oat file says the class had an error, re-run the verifier. That way we will get a
3946 // precise error message. To ensure a rerun, test:
3947 // mirror::Class::IsErroneous(oat_file_class_status) => !preverified
3948 DCHECK(!mirror::Class::IsErroneous(oat_file_class_status) || !preverified);
3950 std::string error_msg;
3951 verifier::MethodVerifier::FailureKind verifier_failure = verifier::MethodVerifier::kNoFailure;
3953 Runtime* runtime = Runtime::Current();
3954 verifier_failure = verifier::MethodVerifier::VerifyClass(self,
3956 runtime->GetCompilerCallbacks(),
3957 runtime->IsAotCompiler(),
3962 // Verification is done, grab the lock again.
3963 ObjectLock<mirror::Class> lock(self, klass);
3965 if (preverified || verifier_failure != verifier::MethodVerifier::kHardFailure) {
3966 if (!preverified && verifier_failure != verifier::MethodVerifier::kNoFailure) {
3967 VLOG(class_linker) << "Soft verification failure in class "
3968 << klass->PrettyDescriptor()
3969 << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8()
3970 << " because: " << error_msg;
3972 self->AssertNoPendingException();
3973 // Make sure all classes referenced by catch blocks are resolved.
3974 ResolveClassExceptionHandlerTypes(klass);
3975 if (verifier_failure == verifier::MethodVerifier::kNoFailure) {
3976 // Even though there were no verifier failures we need to respect whether the super-class and
3977 // super-default-interfaces were verified or requiring runtime reverification.
3978 if (supertype.Get() == nullptr || supertype->IsVerified()) {
3979 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self);
3981 CHECK_EQ(supertype->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime);
3982 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetryVerificationAtRuntime, self);
3983 // Pretend a soft failure occurred so that we don't consider the class verified below.
3984 verifier_failure = verifier::MethodVerifier::kSoftFailure;
3987 CHECK_EQ(verifier_failure, verifier::MethodVerifier::kSoftFailure);
3988 // Soft failures at compile time should be retried at runtime. Soft
3989 // failures at runtime will be handled by slow paths in the generated
3990 // code. Set status accordingly.
3991 if (Runtime::Current()->IsAotCompiler()) {
3992 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetryVerificationAtRuntime, self);
3994 mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, self);
3995 // As this is a fake verified status, make sure the methods are _not_ marked
3996 // kAccSkipAccessChecks later.
3997 klass->SetVerificationAttempted();
4001 VLOG(verifier) << "Verification failed on class " << klass->PrettyDescriptor()
4002 << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8()
4003 << " because: " << error_msg;
4004 self->AssertNoPendingException();
4005 ThrowVerifyError(klass.Get(), "%s", error_msg.c_str());
4006 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorResolved, self);
4008 if (preverified || verifier_failure == verifier::MethodVerifier::kNoFailure) {
4009 // Class is verified so we don't need to do any access check on its methods.
4010 // Let the interpreter know it by setting the kAccSkipAccessChecks flag onto each
4012 // Note: we're going here during compilation and at runtime. When we set the
4013 // kAccSkipAccessChecks flag when compiling image classes, the flag is recorded
4014 // in the image and is set when loading the image.
4016 if (UNLIKELY(Runtime::Current()->IsVerificationSoftFail())) {
4017 // Never skip access checks if the verification soft fail is forced.
4018 // Mark the class as having a verification attempt to avoid re-running the verifier.
4019 klass->SetVerificationAttempted();
4021 EnsureSkipAccessChecksMethods(klass, image_pointer_size_);
4024 return verifier_failure;
4027 bool ClassLinker::VerifyClassUsingOatFile(const DexFile& dex_file,
4028 ObjPtr<mirror::Class> klass,
4029 mirror::Class::Status& oat_file_class_status) {
4030 // If we're compiling, we can only verify the class using the oat file if
4031 // we are not compiling the image or if the class we're verifying is not part of
4032 // the app. In other words, we will only check for preverification of bootclasspath
4034 if (Runtime::Current()->IsAotCompiler()) {
4035 // Are we compiling the bootclasspath?
4036 if (Runtime::Current()->GetCompilerCallbacks()->IsBootImage()) {
4039 // We are compiling an app (not the image).
4041 // Is this an app class? (I.e. not a bootclasspath class)
4042 if (klass->GetClassLoader() != nullptr) {
4047 const OatFile::OatDexFile* oat_dex_file = dex_file.GetOatDexFile();
4048 // In case we run without an image there won't be a backing oat file.
4049 if (oat_dex_file == nullptr || oat_dex_file->GetOatFile() == nullptr) {
4053 // We may be running with a preopted oat file but without image. In this case,
4054 // we don't skip verification of skip_access_checks classes to ensure we initialize
4055 // dex caches with all types resolved during verification.
4056 // We need to trust image classes, as these might be coming out of a pre-opted, quickened boot
4057 // image (that we just failed loading), and the verifier can't be run on quickened opcodes when
4058 // the runtime isn't started. On the other hand, app classes can be re-verified even if they are
4059 // already pre-opted, as then the runtime is started.
4060 if (!Runtime::Current()->IsAotCompiler() &&
4061 !Runtime::Current()->GetHeap()->HasBootImageSpace() &&
4062 klass->GetClassLoader() != nullptr) {
4066 uint16_t class_def_index = klass->GetDexClassDefIndex();
4067 oat_file_class_status = oat_dex_file->GetOatClass(class_def_index).GetStatus();
4068 if (oat_file_class_status == mirror::Class::kStatusVerified ||
4069 oat_file_class_status == mirror::Class::kStatusInitialized) {
4072 // If we only verified a subset of the classes at compile time, we can end up with classes that
4073 // were resolved by the verifier.
4074 if (oat_file_class_status == mirror::Class::kStatusResolved) {
4077 if (oat_file_class_status == mirror::Class::kStatusRetryVerificationAtRuntime) {
4078 // Compile time verification failed with a soft error. Compile time verification can fail
4079 // because we have incomplete type information. Consider the following:
4084 // v1 gets assigned a type of resolved class Foo
4086 // v1 gets assigned a type of unresolved class Bar
4090 // when we merge v1 following the if-the-else it results in Conflict
4091 // (see verifier::RegType::Merge) as we can't know the type of Bar and we could possibly be
4092 // allowing an unsafe assignment to the field x in the iput (javac may have compiled this as
4093 // it knew Bar was a sub-class of Foo, but for us this may have been moved into a separate apk
4094 // at compile time).
4097 if (mirror::Class::IsErroneous(oat_file_class_status)) {
4098 // Compile time verification failed with a hard error. This is caused by invalid instructions
4099 // in the class. These errors are unrecoverable.
4102 if (oat_file_class_status == mirror::Class::kStatusNotReady) {
4103 // Status is uninitialized if we couldn't determine the status at compile time, for example,
4104 // not loading the class.
4105 // TODO: when the verifier doesn't rely on Class-es failing to resolve/load the type hierarchy
4106 // isn't a problem and this case shouldn't occur
4110 LOG(FATAL) << "Unexpected class status: " << oat_file_class_status
4111 << " " << dex_file.GetLocation() << " " << klass->PrettyClass() << " "
4112 << klass->GetDescriptor(&temp);
4116 void ClassLinker::ResolveClassExceptionHandlerTypes(Handle<mirror::Class> klass) {
4117 for (ArtMethod& method : klass->GetMethods(image_pointer_size_)) {
4118 ResolveMethodExceptionHandlerTypes(&method);
4122 void ClassLinker::ResolveMethodExceptionHandlerTypes(ArtMethod* method) {
4123 // similar to DexVerifier::ScanTryCatchBlocks and dex2oat's ResolveExceptionsForMethod.
4124 const DexFile::CodeItem* code_item =
4125 method->GetDexFile()->GetCodeItem(method->GetCodeItemOffset());
4126 if (code_item == nullptr) {
4127 return; // native or abstract method
4129 if (code_item->tries_size_ == 0) {
4130 return; // nothing to process
4132 const uint8_t* handlers_ptr = DexFile::GetCatchHandlerData(*code_item, 0);
4133 uint32_t handlers_size = DecodeUnsignedLeb128(&handlers_ptr);
4134 for (uint32_t idx = 0; idx < handlers_size; idx++) {
4135 CatchHandlerIterator iterator(handlers_ptr);
4136 for (; iterator.HasNext(); iterator.Next()) {
4137 // Ensure exception types are resolved so that they don't need resolution to be delivered,
4138 // unresolved exception types will be ignored by exception delivery
4139 if (iterator.GetHandlerTypeIndex().IsValid()) {
4140 ObjPtr<mirror::Class> exception_type = ResolveType(iterator.GetHandlerTypeIndex(), method);
4141 if (exception_type == nullptr) {
4142 DCHECK(Thread::Current()->IsExceptionPending());
4143 Thread::Current()->ClearException();
4147 handlers_ptr = iterator.EndDataPointer();
4151 mirror::Class* ClassLinker::CreateProxyClass(ScopedObjectAccessAlreadyRunnable& soa,
4153 jobjectArray interfaces,
4155 jobjectArray methods,
4156 jobjectArray throws) {
4157 Thread* self = soa.Self();
4158 StackHandleScope<10> hs(self);
4159 MutableHandle<mirror::Class> klass(hs.NewHandle(
4160 AllocClass(self, GetClassRoot(kJavaLangClass), sizeof(mirror::Class))));
4161 if (klass.Get() == nullptr) {
4162 CHECK(self->IsExceptionPending()); // OOME.
4165 DCHECK(klass->GetClass() != nullptr);
4166 klass->SetObjectSize(sizeof(mirror::Proxy));
4167 // Set the class access flags incl. VerificationAttempted, so we do not try to set the flag on
4169 klass->SetAccessFlags(kAccClassIsProxy | kAccPublic | kAccFinal | kAccVerificationAttempted);
4170 klass->SetClassLoader(soa.Decode<mirror::ClassLoader>(loader));
4171 DCHECK_EQ(klass->GetPrimitiveType(), Primitive::kPrimNot);
4172 klass->SetName(soa.Decode<mirror::String>(name));
4173 klass->SetDexCache(GetClassRoot(kJavaLangReflectProxy)->GetDexCache());
4174 // Object has an empty iftable, copy it for that reason.
4175 klass->SetIfTable(GetClassRoot(kJavaLangObject)->GetIfTable());
4176 mirror::Class::SetStatus(klass, mirror::Class::kStatusIdx, self);
4177 std::string descriptor(GetDescriptorForProxy(klass.Get()));
4178 const size_t hash = ComputeModifiedUtf8Hash(descriptor.c_str());
4180 // Needs to be before we insert the class so that the allocator field is set.
4181 LinearAlloc* const allocator = GetOrCreateAllocatorForClassLoader(klass->GetClassLoader());
4183 // Insert the class before loading the fields as the field roots
4184 // (ArtField::declaring_class_) are only visited from the class
4185 // table. There can't be any suspend points between inserting the
4186 // class and setting the field arrays below.
4187 ObjPtr<mirror::Class> existing = InsertClass(descriptor.c_str(), klass.Get(), hash);
4188 CHECK(existing == nullptr);
4190 // Instance fields are inherited, but we add a couple of static fields...
4191 const size_t num_fields = 2;
4192 LengthPrefixedArray<ArtField>* sfields = AllocArtFieldArray(self, allocator, num_fields);
4193 klass->SetSFieldsPtr(sfields);
4195 // 1. Create a static field 'interfaces' that holds the _declared_ interfaces implemented by
4196 // our proxy, so Class.getInterfaces doesn't return the flattened set.
4197 ArtField& interfaces_sfield = sfields->At(0);
4198 interfaces_sfield.SetDexFieldIndex(0);
4199 interfaces_sfield.SetDeclaringClass(klass.Get());
4200 interfaces_sfield.SetAccessFlags(kAccStatic | kAccPublic | kAccFinal);
4202 // 2. Create a static field 'throws' that holds exceptions thrown by our methods.
4203 ArtField& throws_sfield = sfields->At(1);
4204 throws_sfield.SetDexFieldIndex(1);
4205 throws_sfield.SetDeclaringClass(klass.Get());
4206 throws_sfield.SetAccessFlags(kAccStatic | kAccPublic | kAccFinal);
4208 // Proxies have 1 direct method, the constructor
4209 const size_t num_direct_methods = 1;
4211 // They have as many virtual methods as the array
4212 auto h_methods = hs.NewHandle(soa.Decode<mirror::ObjectArray<mirror::Method>>(methods));
4213 DCHECK_EQ(h_methods->GetClass(), mirror::Method::ArrayClass())
4214 << mirror::Class::PrettyClass(h_methods->GetClass());
4215 const size_t num_virtual_methods = h_methods->GetLength();
4217 // Create the methods array.
4218 LengthPrefixedArray<ArtMethod>* proxy_class_methods = AllocArtMethodArray(
4219 self, allocator, num_direct_methods + num_virtual_methods);
4220 // Currently AllocArtMethodArray cannot return null, but the OOM logic is left there in case we
4221 // want to throw OOM in the future.
4222 if (UNLIKELY(proxy_class_methods == nullptr)) {
4223 self->AssertPendingOOMException();
4226 klass->SetMethodsPtr(proxy_class_methods, num_direct_methods, num_virtual_methods);
4228 // Create the single direct method.
4229 CreateProxyConstructor(klass, klass->GetDirectMethodUnchecked(0, image_pointer_size_));
4231 // Create virtual method using specified prototypes.
4232 // TODO These should really use the iterators.
4233 for (size_t i = 0; i < num_virtual_methods; ++i) {
4234 auto* virtual_method = klass->GetVirtualMethodUnchecked(i, image_pointer_size_);
4235 auto* prototype = h_methods->Get(i)->GetArtMethod();
4236 CreateProxyMethod(klass, prototype, virtual_method);
4237 DCHECK(virtual_method->GetDeclaringClass() != nullptr);
4238 DCHECK(prototype->GetDeclaringClass() != nullptr);
4241 // The super class is java.lang.reflect.Proxy
4242 klass->SetSuperClass(GetClassRoot(kJavaLangReflectProxy));
4243 // Now effectively in the loaded state.
4244 mirror::Class::SetStatus(klass, mirror::Class::kStatusLoaded, self);
4245 self->AssertNoPendingException();
4247 MutableHandle<mirror::Class> new_class = hs.NewHandle<mirror::Class>(nullptr);
4249 // Must hold lock on object when resolved.
4250 ObjectLock<mirror::Class> resolution_lock(self, klass);
4251 // Link the fields and virtual methods, creating vtable and iftables.
4252 // The new class will replace the old one in the class table.
4253 Handle<mirror::ObjectArray<mirror::Class>> h_interfaces(
4254 hs.NewHandle(soa.Decode<mirror::ObjectArray<mirror::Class>>(interfaces)));
4255 if (!LinkClass(self, descriptor.c_str(), klass, h_interfaces, &new_class)) {
4256 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorUnresolved, self);
4260 CHECK(klass->IsRetired());
4261 CHECK_NE(klass.Get(), new_class.Get());
4262 klass.Assign(new_class.Get());
4264 CHECK_EQ(interfaces_sfield.GetDeclaringClass(), klass.Get());
4265 interfaces_sfield.SetObject<false>(
4267 soa.Decode<mirror::ObjectArray<mirror::Class>>(interfaces));
4268 CHECK_EQ(throws_sfield.GetDeclaringClass(), klass.Get());
4269 throws_sfield.SetObject<false>(
4271 soa.Decode<mirror::ObjectArray<mirror::ObjectArray<mirror::Class>>>(throws));
4274 // Lock on klass is released. Lock new class object.
4275 ObjectLock<mirror::Class> initialization_lock(self, klass);
4276 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitialized, self);
4280 if (kIsDebugBuild) {
4281 CHECK(klass->GetIFieldsPtr() == nullptr);
4282 CheckProxyConstructor(klass->GetDirectMethod(0, image_pointer_size_));
4284 for (size_t i = 0; i < num_virtual_methods; ++i) {
4285 auto* virtual_method = klass->GetVirtualMethodUnchecked(i, image_pointer_size_);
4286 auto* prototype = h_methods->Get(i++)->GetArtMethod();
4287 CheckProxyMethod(virtual_method, prototype);
4290 StackHandleScope<1> hs2(self);
4291 Handle<mirror::String> decoded_name = hs2.NewHandle(soa.Decode<mirror::String>(name));
4292 std::string interfaces_field_name(StringPrintf("java.lang.Class[] %s.interfaces",
4293 decoded_name->ToModifiedUtf8().c_str()));
4294 CHECK_EQ(ArtField::PrettyField(klass->GetStaticField(0)), interfaces_field_name);
4296 std::string throws_field_name(StringPrintf("java.lang.Class[][] %s.throws",
4297 decoded_name->ToModifiedUtf8().c_str()));
4298 CHECK_EQ(ArtField::PrettyField(klass->GetStaticField(1)), throws_field_name);
4300 CHECK_EQ(klass.Get()->GetInterfaces(),
4301 soa.Decode<mirror::ObjectArray<mirror::Class>>(interfaces));
4302 CHECK_EQ(klass.Get()->GetThrows(),
4303 soa.Decode<mirror::ObjectArray<mirror::ObjectArray<mirror::Class>>>(throws));
4308 std::string ClassLinker::GetDescriptorForProxy(ObjPtr<mirror::Class> proxy_class) {
4309 DCHECK(proxy_class->IsProxyClass());
4310 ObjPtr<mirror::String> name = proxy_class->GetName();
4311 DCHECK(name != nullptr);
4312 return DotToDescriptor(name->ToModifiedUtf8().c_str());
4315 void ClassLinker::CreateProxyConstructor(Handle<mirror::Class> klass, ArtMethod* out) {
4316 // Create constructor for Proxy that must initialize the method.
4317 CHECK_EQ(GetClassRoot(kJavaLangReflectProxy)->NumDirectMethods(), 23u);
4319 ArtMethod* proxy_constructor = GetClassRoot(kJavaLangReflectProxy)->GetDirectMethodUnchecked(
4320 8, image_pointer_size_);
4321 DCHECK_EQ(std::string(proxy_constructor->GetName()), "<init>");
4322 // Ensure constructor is in dex cache so that we can use the dex cache to look up the overridden
4323 // constructor method.
4324 GetClassRoot(kJavaLangReflectProxy)->GetDexCache()->SetResolvedMethod(
4325 proxy_constructor->GetDexMethodIndex(), proxy_constructor, image_pointer_size_);
4326 // Clone the existing constructor of Proxy (our constructor would just invoke it so steal its
4328 DCHECK(out != nullptr);
4329 out->CopyFrom(proxy_constructor, image_pointer_size_);
4330 // Make this constructor public and fix the class to be our Proxy version
4331 out->SetAccessFlags((out->GetAccessFlags() & ~kAccProtected) | kAccPublic);
4332 out->SetDeclaringClass(klass.Get());
4335 void ClassLinker::CheckProxyConstructor(ArtMethod* constructor) const {
4336 CHECK(constructor->IsConstructor());
4337 auto* np = constructor->GetInterfaceMethodIfProxy(image_pointer_size_);
4338 CHECK_STREQ(np->GetName(), "<init>");
4339 CHECK_STREQ(np->GetSignature().ToString().c_str(), "(Ljava/lang/reflect/InvocationHandler;)V");
4340 DCHECK(constructor->IsPublic());
4343 void ClassLinker::CreateProxyMethod(Handle<mirror::Class> klass, ArtMethod* prototype,
4345 // Ensure prototype is in dex cache so that we can use the dex cache to look up the overridden
4347 auto* dex_cache = prototype->GetDeclaringClass()->GetDexCache();
4348 // Avoid dirtying the dex cache unless we need to.
4349 if (dex_cache->GetResolvedMethod(prototype->GetDexMethodIndex(), image_pointer_size_) !=
4351 dex_cache->SetResolvedMethod(
4352 prototype->GetDexMethodIndex(), prototype, image_pointer_size_);
4354 // We steal everything from the prototype (such as DexCache, invoke stub, etc.) then specialize
4356 DCHECK(out != nullptr);
4357 out->CopyFrom(prototype, image_pointer_size_);
4359 // Set class to be the concrete proxy class.
4360 out->SetDeclaringClass(klass.Get());
4361 // Clear the abstract, default and conflict flags to ensure that defaults aren't picked in
4362 // preference to the invocation handler.
4363 const uint32_t kRemoveFlags = kAccAbstract | kAccDefault | kAccDefaultConflict;
4364 // Make the method final.
4365 const uint32_t kAddFlags = kAccFinal;
4366 out->SetAccessFlags((out->GetAccessFlags() & ~kRemoveFlags) | kAddFlags);
4368 // Clear the dex_code_item_offset_. It needs to be 0 since proxy methods have no CodeItems but the
4369 // method they copy might (if it's a default method).
4370 out->SetCodeItemOffset(0);
4372 // At runtime the method looks like a reference and argument saving method, clone the code
4373 // related parameters from this method.
4374 out->SetEntryPointFromQuickCompiledCode(GetQuickProxyInvokeHandler());
4377 void ClassLinker::CheckProxyMethod(ArtMethod* method, ArtMethod* prototype) const {
4379 CHECK(!prototype->IsFinal());
4380 CHECK(method->IsFinal());
4381 CHECK(method->IsInvokable());
4383 // The proxy method doesn't have its own dex cache or dex file and so it steals those of its
4384 // interface prototype. The exception to this are Constructors and the Class of the Proxy itself.
4385 CHECK(prototype->HasSameDexCacheResolvedMethods(method, image_pointer_size_));
4386 auto* np = method->GetInterfaceMethodIfProxy(image_pointer_size_);
4387 CHECK_EQ(prototype->GetDeclaringClass()->GetDexCache(), np->GetDexCache());
4388 CHECK_EQ(prototype->GetDexMethodIndex(), method->GetDexMethodIndex());
4390 CHECK_STREQ(np->GetName(), prototype->GetName());
4391 CHECK_STREQ(np->GetShorty(), prototype->GetShorty());
4392 // More complex sanity - via dex cache
4393 CHECK_EQ(np->GetReturnType(true /* resolve */), prototype->GetReturnType(true /* resolve */));
4396 bool ClassLinker::CanWeInitializeClass(ObjPtr<mirror::Class> klass, bool can_init_statics,
4397 bool can_init_parents) {
4398 if (can_init_statics && can_init_parents) {
4401 if (!can_init_statics) {
4402 // Check if there's a class initializer.
4403 ArtMethod* clinit = klass->FindClassInitializer(image_pointer_size_);
4404 if (clinit != nullptr) {
4407 // Check if there are encoded static values needing initialization.
4408 if (klass->NumStaticFields() != 0) {
4409 const DexFile::ClassDef* dex_class_def = klass->GetClassDef();
4410 DCHECK(dex_class_def != nullptr);
4411 if (dex_class_def->static_values_off_ != 0) {
4415 // If we are a class we need to initialize all interfaces with default methods when we are
4416 // initialized. Check all of them.
4417 if (!klass->IsInterface()) {
4418 size_t num_interfaces = klass->GetIfTableCount();
4419 for (size_t i = 0; i < num_interfaces; i++) {
4420 ObjPtr<mirror::Class> iface = klass->GetIfTable()->GetInterface(i);
4421 if (iface->HasDefaultMethods() &&
4422 !CanWeInitializeClass(iface, can_init_statics, can_init_parents)) {
4428 if (klass->IsInterface() || !klass->HasSuperClass()) {
4431 ObjPtr<mirror::Class> super_class = klass->GetSuperClass();
4432 if (!can_init_parents && !super_class->IsInitialized()) {
4435 return CanWeInitializeClass(super_class, can_init_statics, can_init_parents);
4438 bool ClassLinker::InitializeClass(Thread* self, Handle<mirror::Class> klass,
4439 bool can_init_statics, bool can_init_parents) {
4440 // see JLS 3rd edition, 12.4.2 "Detailed Initialization Procedure" for the locking protocol
4442 // Are we already initialized and therefore done?
4443 // Note: we differ from the JLS here as we don't do this under the lock, this is benign as
4444 // an initialized class will never change its state.
4445 if (klass->IsInitialized()) {
4449 // Fast fail if initialization requires a full runtime. Not part of the JLS.
4450 if (!CanWeInitializeClass(klass.Get(), can_init_statics, can_init_parents)) {
4454 self->AllowThreadSuspension();
4457 ObjectLock<mirror::Class> lock(self, klass);
4459 // Re-check under the lock in case another thread initialized ahead of us.
4460 if (klass->IsInitialized()) {
4464 // Was the class already found to be erroneous? Done under the lock to match the JLS.
4465 if (klass->IsErroneous()) {
4466 ThrowEarlierClassFailure(klass.Get(), true);
4467 VlogClassInitializationFailure(klass);
4471 CHECK(klass->IsResolved() && !klass->IsErroneousResolved())
4472 << klass->PrettyClass() << ": state=" << klass->GetStatus();
4474 if (!klass->IsVerified()) {
4475 VerifyClass(self, klass);
4476 if (!klass->IsVerified()) {
4477 // We failed to verify, expect either the klass to be erroneous or verification failed at
4479 if (klass->IsErroneous()) {
4480 // The class is erroneous. This may be a verifier error, or another thread attempted
4481 // verification and/or initialization and failed. We can distinguish those cases by
4482 // whether an exception is already pending.
4483 if (self->IsExceptionPending()) {
4484 // Check that it's a VerifyError.
4485 DCHECK_EQ("java.lang.Class<java.lang.VerifyError>",
4486 mirror::Class::PrettyClass(self->GetException()->GetClass()));
4488 // Check that another thread attempted initialization.
4489 DCHECK_NE(0, klass->GetClinitThreadId());
4490 DCHECK_NE(self->GetTid(), klass->GetClinitThreadId());
4491 // Need to rethrow the previous failure now.
4492 ThrowEarlierClassFailure(klass.Get(), true);
4494 VlogClassInitializationFailure(klass);
4496 CHECK(Runtime::Current()->IsAotCompiler());
4497 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime);
4501 self->AssertNoPendingException();
4504 // A separate thread could have moved us all the way to initialized. A "simple" example
4505 // involves a subclass of the current class being initialized at the same time (which
4506 // will implicitly initialize the superclass, if scheduled that way). b/28254258
4507 DCHECK(!klass->IsErroneous()) << klass->GetStatus();
4508 if (klass->IsInitialized()) {
4513 // If the class is kStatusInitializing, either this thread is
4514 // initializing higher up the stack or another thread has beat us
4515 // to initializing and we need to wait. Either way, this
4516 // invocation of InitializeClass will not be responsible for
4517 // running <clinit> and will return.
4518 if (klass->GetStatus() == mirror::Class::kStatusInitializing) {
4519 // Could have got an exception during verification.
4520 if (self->IsExceptionPending()) {
4521 VlogClassInitializationFailure(klass);
4524 // We caught somebody else in the act; was it us?
4525 if (klass->GetClinitThreadId() == self->GetTid()) {
4526 // Yes. That's fine. Return so we can continue initializing.
4529 // No. That's fine. Wait for another thread to finish initializing.
4530 return WaitForInitializeClass(klass, self, lock);
4533 if (!ValidateSuperClassDescriptors(klass)) {
4534 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorResolved, self);
4537 self->AllowThreadSuspension();
4539 CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusVerified) << klass->PrettyClass()
4540 << " self.tid=" << self->GetTid() << " clinit.tid=" << klass->GetClinitThreadId();
4542 // From here out other threads may observe that we're initializing and so changes of state
4543 // require the a notification.
4544 klass->SetClinitThreadId(self->GetTid());
4545 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitializing, self);
4550 // Initialize super classes, must be done while initializing for the JLS.
4551 if (!klass->IsInterface() && klass->HasSuperClass()) {
4552 ObjPtr<mirror::Class> super_class = klass->GetSuperClass();
4553 if (!super_class->IsInitialized()) {
4554 CHECK(!super_class->IsInterface());
4555 CHECK(can_init_parents);
4556 StackHandleScope<1> hs(self);
4557 Handle<mirror::Class> handle_scope_super(hs.NewHandle(super_class));
4558 bool super_initialized = InitializeClass(self, handle_scope_super, can_init_statics, true);
4559 if (!super_initialized) {
4560 // The super class was verified ahead of entering initializing, we should only be here if
4561 // the super class became erroneous due to initialization.
4562 CHECK(handle_scope_super->IsErroneous() && self->IsExceptionPending())
4563 << "Super class initialization failed for "
4564 << handle_scope_super->PrettyDescriptor()
4565 << " that has unexpected status " << handle_scope_super->GetStatus()
4566 << "\nPending exception:\n"
4567 << (self->GetException() != nullptr ? self->GetException()->Dump() : "");
4568 ObjectLock<mirror::Class> lock(self, klass);
4569 // Initialization failed because the super-class is erroneous.
4570 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorResolved, self);
4576 if (!klass->IsInterface()) {
4577 // Initialize interfaces with default methods for the JLS.
4578 size_t num_direct_interfaces = klass->NumDirectInterfaces();
4579 // Only setup the (expensive) handle scope if we actually need to.
4580 if (UNLIKELY(num_direct_interfaces > 0)) {
4581 StackHandleScope<1> hs_iface(self);
4582 MutableHandle<mirror::Class> handle_scope_iface(hs_iface.NewHandle<mirror::Class>(nullptr));
4583 for (size_t i = 0; i < num_direct_interfaces; i++) {
4584 handle_scope_iface.Assign(mirror::Class::GetDirectInterface(self, klass.Get(), i));
4585 CHECK(handle_scope_iface.Get() != nullptr);
4586 CHECK(handle_scope_iface->IsInterface());
4587 if (handle_scope_iface->HasBeenRecursivelyInitialized()) {
4588 // We have already done this for this interface. Skip it.
4591 // We cannot just call initialize class directly because we need to ensure that ALL
4592 // interfaces with default methods are initialized. Non-default interface initialization
4593 // will not affect other non-default super-interfaces.
4594 bool iface_initialized = InitializeDefaultInterfaceRecursive(self,
4598 if (!iface_initialized) {
4599 ObjectLock<mirror::Class> lock(self, klass);
4600 // Initialization failed because one of our interfaces with default methods is erroneous.
4601 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorResolved, self);
4608 const size_t num_static_fields = klass->NumStaticFields();
4609 if (num_static_fields > 0) {
4610 const DexFile::ClassDef* dex_class_def = klass->GetClassDef();
4611 CHECK(dex_class_def != nullptr);
4612 const DexFile& dex_file = klass->GetDexFile();
4613 StackHandleScope<3> hs(self);
4614 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(klass->GetClassLoader()));
4615 Handle<mirror::DexCache> dex_cache(hs.NewHandle(klass->GetDexCache()));
4617 // Eagerly fill in static fields so that the we don't have to do as many expensive
4618 // Class::FindStaticField in ResolveField.
4619 for (size_t i = 0; i < num_static_fields; ++i) {
4620 ArtField* field = klass->GetStaticField(i);
4621 const uint32_t field_idx = field->GetDexFieldIndex();
4622 ArtField* resolved_field = dex_cache->GetResolvedField(field_idx, image_pointer_size_);
4623 if (resolved_field == nullptr) {
4624 dex_cache->SetResolvedField(field_idx, field, image_pointer_size_);
4626 DCHECK_EQ(field, resolved_field);
4630 annotations::RuntimeEncodedStaticFieldValueIterator value_it(dex_file,
4635 const uint8_t* class_data = dex_file.GetClassData(*dex_class_def);
4636 ClassDataItemIterator field_it(dex_file, class_data);
4637 if (value_it.HasNext()) {
4638 DCHECK(field_it.HasNextStaticField());
4639 CHECK(can_init_statics);
4640 for ( ; value_it.HasNext(); value_it.Next(), field_it.Next()) {
4641 ArtField* field = ResolveField(
4642 dex_file, field_it.GetMemberIndex(), dex_cache, class_loader, true);
4643 if (Runtime::Current()->IsActiveTransaction()) {
4644 value_it.ReadValueToField<true>(field);
4646 value_it.ReadValueToField<false>(field);
4648 if (self->IsExceptionPending()) {
4651 DCHECK(!value_it.HasNext() || field_it.HasNextStaticField());
4657 if (!self->IsExceptionPending()) {
4658 ArtMethod* clinit = klass->FindClassInitializer(image_pointer_size_);
4659 if (clinit != nullptr) {
4660 CHECK(can_init_statics);
4662 clinit->Invoke(self, nullptr, 0, &result, "V");
4665 self->AllowThreadSuspension();
4666 uint64_t t1 = NanoTime();
4668 bool success = true;
4670 ObjectLock<mirror::Class> lock(self, klass);
4672 if (self->IsExceptionPending()) {
4673 WrapExceptionInInitializer(klass);
4674 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorResolved, self);
4676 } else if (Runtime::Current()->IsTransactionAborted()) {
4677 // The exception thrown when the transaction aborted has been caught and cleared
4678 // so we need to throw it again now.
4679 VLOG(compiler) << "Return from class initializer of "
4680 << mirror::Class::PrettyDescriptor(klass.Get())
4681 << " without exception while transaction was aborted: re-throw it now.";
4682 Runtime::Current()->ThrowTransactionAbortError(self);
4683 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorResolved, self);
4686 RuntimeStats* global_stats = Runtime::Current()->GetStats();
4687 RuntimeStats* thread_stats = self->GetStats();
4688 ++global_stats->class_init_count;
4689 ++thread_stats->class_init_count;
4690 global_stats->class_init_time_ns += (t1 - t0);
4691 thread_stats->class_init_time_ns += (t1 - t0);
4692 // Set the class as initialized except if failed to initialize static fields.
4693 mirror::Class::SetStatus(klass, mirror::Class::kStatusInitialized, self);
4694 if (VLOG_IS_ON(class_linker)) {
4696 LOG(INFO) << "Initialized class " << klass->GetDescriptor(&temp) << " from " <<
4697 klass->GetLocation();
4699 // Opportunistically set static method trampolines to their destination.
4700 FixupStaticTrampolines(klass.Get());
4706 // We recursively run down the tree of interfaces. We need to do this in the order they are declared
4707 // and perform the initialization only on those interfaces that contain default methods.
4708 bool ClassLinker::InitializeDefaultInterfaceRecursive(Thread* self,
4709 Handle<mirror::Class> iface,
4710 bool can_init_statics,
4711 bool can_init_parents) {
4712 CHECK(iface->IsInterface());
4713 size_t num_direct_ifaces = iface->NumDirectInterfaces();
4714 // Only create the (expensive) handle scope if we need it.
4715 if (UNLIKELY(num_direct_ifaces > 0)) {
4716 StackHandleScope<1> hs(self);
4717 MutableHandle<mirror::Class> handle_super_iface(hs.NewHandle<mirror::Class>(nullptr));
4718 // First we initialize all of iface's super-interfaces recursively.
4719 for (size_t i = 0; i < num_direct_ifaces; i++) {
4720 ObjPtr<mirror::Class> super_iface = mirror::Class::GetDirectInterface(self, iface.Get(), i);
4721 DCHECK(super_iface != nullptr);
4722 if (!super_iface->HasBeenRecursivelyInitialized()) {
4724 handle_super_iface.Assign(super_iface);
4725 if (!InitializeDefaultInterfaceRecursive(self,
4728 can_init_parents)) {
4736 // Then we initialize 'iface' if it has default methods. We do not need to (and in fact must not)
4737 // initialize if we don't have default methods.
4738 if (iface->HasDefaultMethods()) {
4739 result = EnsureInitialized(self, iface, can_init_statics, can_init_parents);
4742 // Mark that this interface has undergone recursive default interface initialization so we know we
4743 // can skip it on any later class initializations. We do this even if we are not a default
4744 // interface since we can still avoid the traversal. This is purely a performance optimization.
4746 // TODO This should be done in a better way
4747 ObjectLock<mirror::Class> lock(self, iface);
4748 iface->SetRecursivelyInitialized();
4753 bool ClassLinker::WaitForInitializeClass(Handle<mirror::Class> klass,
4755 ObjectLock<mirror::Class>& lock)
4756 REQUIRES_SHARED(Locks::mutator_lock_) {
4758 self->AssertNoPendingException();
4759 CHECK(!klass->IsInitialized());
4760 lock.WaitIgnoringInterrupts();
4762 // When we wake up, repeat the test for init-in-progress. If
4763 // there's an exception pending (only possible if
4764 // we were not using WaitIgnoringInterrupts), bail out.
4765 if (self->IsExceptionPending()) {
4766 WrapExceptionInInitializer(klass);
4767 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorResolved, self);
4770 // Spurious wakeup? Go back to waiting.
4771 if (klass->GetStatus() == mirror::Class::kStatusInitializing) {
4774 if (klass->GetStatus() == mirror::Class::kStatusVerified &&
4775 Runtime::Current()->IsAotCompiler()) {
4776 // Compile time initialization failed.
4779 if (klass->IsErroneous()) {
4780 // The caller wants an exception, but it was thrown in a
4781 // different thread. Synthesize one here.
4782 ThrowNoClassDefFoundError("<clinit> failed for class %s; see exception in other thread",
4783 klass->PrettyDescriptor().c_str());
4784 VlogClassInitializationFailure(klass);
4787 if (klass->IsInitialized()) {
4790 LOG(FATAL) << "Unexpected class status. " << klass->PrettyClass() << " is "
4791 << klass->GetStatus();
4796 static void ThrowSignatureCheckResolveReturnTypeException(Handle<mirror::Class> klass,
4797 Handle<mirror::Class> super_klass,
4800 REQUIRES_SHARED(Locks::mutator_lock_) {
4801 DCHECK(Thread::Current()->IsExceptionPending());
4802 DCHECK(!m->IsProxyMethod());
4803 const DexFile* dex_file = m->GetDexFile();
4804 const DexFile::MethodId& method_id = dex_file->GetMethodId(m->GetDexMethodIndex());
4805 const DexFile::ProtoId& proto_id = dex_file->GetMethodPrototype(method_id);
4806 dex::TypeIndex return_type_idx = proto_id.return_type_idx_;
4807 std::string return_type = dex_file->PrettyType(return_type_idx);
4808 std::string class_loader = mirror::Object::PrettyTypeOf(m->GetDeclaringClass()->GetClassLoader());
4809 ThrowWrappedLinkageError(klass.Get(),
4810 "While checking class %s method %s signature against %s %s: "
4811 "Failed to resolve return type %s with %s",
4812 mirror::Class::PrettyDescriptor(klass.Get()).c_str(),
4813 ArtMethod::PrettyMethod(method).c_str(),
4814 super_klass->IsInterface() ? "interface" : "superclass",
4815 mirror::Class::PrettyDescriptor(super_klass.Get()).c_str(),
4816 return_type.c_str(), class_loader.c_str());
4819 static void ThrowSignatureCheckResolveArgException(Handle<mirror::Class> klass,
4820 Handle<mirror::Class> super_klass,
4824 dex::TypeIndex arg_type_idx)
4825 REQUIRES_SHARED(Locks::mutator_lock_) {
4826 DCHECK(Thread::Current()->IsExceptionPending());
4827 DCHECK(!m->IsProxyMethod());
4828 const DexFile* dex_file = m->GetDexFile();
4829 std::string arg_type = dex_file->PrettyType(arg_type_idx);
4830 std::string class_loader = mirror::Object::PrettyTypeOf(m->GetDeclaringClass()->GetClassLoader());
4831 ThrowWrappedLinkageError(klass.Get(),
4832 "While checking class %s method %s signature against %s %s: "
4833 "Failed to resolve arg %u type %s with %s",
4834 mirror::Class::PrettyDescriptor(klass.Get()).c_str(),
4835 ArtMethod::PrettyMethod(method).c_str(),
4836 super_klass->IsInterface() ? "interface" : "superclass",
4837 mirror::Class::PrettyDescriptor(super_klass.Get()).c_str(),
4838 index, arg_type.c_str(), class_loader.c_str());
4841 static void ThrowSignatureMismatch(Handle<mirror::Class> klass,
4842 Handle<mirror::Class> super_klass,
4844 const std::string& error_msg)
4845 REQUIRES_SHARED(Locks::mutator_lock_) {
4846 ThrowLinkageError(klass.Get(),
4847 "Class %s method %s resolves differently in %s %s: %s",
4848 mirror::Class::PrettyDescriptor(klass.Get()).c_str(),
4849 ArtMethod::PrettyMethod(method).c_str(),
4850 super_klass->IsInterface() ? "interface" : "superclass",
4851 mirror::Class::PrettyDescriptor(super_klass.Get()).c_str(),
4855 static bool HasSameSignatureWithDifferentClassLoaders(Thread* self,
4856 Handle<mirror::Class> klass,
4857 Handle<mirror::Class> super_klass,
4860 REQUIRES_SHARED(Locks::mutator_lock_) {
4862 StackHandleScope<1> hs(self);
4863 Handle<mirror::Class> return_type(hs.NewHandle(method1->GetReturnType(true /* resolve */)));
4864 if (UNLIKELY(return_type.Get() == nullptr)) {
4865 ThrowSignatureCheckResolveReturnTypeException(klass, super_klass, method1, method1);
4868 ObjPtr<mirror::Class> other_return_type = method2->GetReturnType(true /* resolve */);
4869 if (UNLIKELY(other_return_type == nullptr)) {
4870 ThrowSignatureCheckResolveReturnTypeException(klass, super_klass, method1, method2);
4873 if (UNLIKELY(other_return_type != return_type.Get())) {
4874 ThrowSignatureMismatch(klass, super_klass, method1,
4875 StringPrintf("Return types mismatch: %s(%p) vs %s(%p)",
4876 return_type->PrettyClassAndClassLoader().c_str(),
4878 other_return_type->PrettyClassAndClassLoader().c_str(),
4879 other_return_type.Ptr()));
4883 const DexFile::TypeList* types1 = method1->GetParameterTypeList();
4884 const DexFile::TypeList* types2 = method2->GetParameterTypeList();
4885 if (types1 == nullptr) {
4886 if (types2 != nullptr && types2->Size() != 0) {
4887 ThrowSignatureMismatch(klass, super_klass, method1,
4888 StringPrintf("Type list mismatch with %s",
4889 method2->PrettyMethod(true).c_str()));
4893 } else if (UNLIKELY(types2 == nullptr)) {
4894 if (types1->Size() != 0) {
4895 ThrowSignatureMismatch(klass, super_klass, method1,
4896 StringPrintf("Type list mismatch with %s",
4897 method2->PrettyMethod(true).c_str()));
4902 uint32_t num_types = types1->Size();
4903 if (UNLIKELY(num_types != types2->Size())) {
4904 ThrowSignatureMismatch(klass, super_klass, method1,
4905 StringPrintf("Type list mismatch with %s",
4906 method2->PrettyMethod(true).c_str()));
4909 for (uint32_t i = 0; i < num_types; ++i) {
4910 StackHandleScope<1> hs(self);
4911 dex::TypeIndex param_type_idx = types1->GetTypeItem(i).type_idx_;
4912 Handle<mirror::Class> param_type(hs.NewHandle(
4913 method1->GetClassFromTypeIndex(param_type_idx, true /* resolve */)));
4914 if (UNLIKELY(param_type.Get() == nullptr)) {
4915 ThrowSignatureCheckResolveArgException(klass, super_klass, method1,
4916 method1, i, param_type_idx);
4919 dex::TypeIndex other_param_type_idx = types2->GetTypeItem(i).type_idx_;
4920 ObjPtr<mirror::Class> other_param_type =
4921 method2->GetClassFromTypeIndex(other_param_type_idx, true /* resolve */);
4922 if (UNLIKELY(other_param_type == nullptr)) {
4923 ThrowSignatureCheckResolveArgException(klass, super_klass, method1,
4924 method2, i, other_param_type_idx);
4927 if (UNLIKELY(param_type.Get() != other_param_type)) {
4928 ThrowSignatureMismatch(klass, super_klass, method1,
4929 StringPrintf("Parameter %u type mismatch: %s(%p) vs %s(%p)",
4931 param_type->PrettyClassAndClassLoader().c_str(),
4933 other_param_type->PrettyClassAndClassLoader().c_str(),
4934 other_param_type.Ptr()));
4942 bool ClassLinker::ValidateSuperClassDescriptors(Handle<mirror::Class> klass) {
4943 if (klass->IsInterface()) {
4946 // Begin with the methods local to the superclass.
4947 Thread* self = Thread::Current();
4948 StackHandleScope<1> hs(self);
4949 MutableHandle<mirror::Class> super_klass(hs.NewHandle<mirror::Class>(nullptr));
4950 if (klass->HasSuperClass() &&
4951 klass->GetClassLoader() != klass->GetSuperClass()->GetClassLoader()) {
4952 super_klass.Assign(klass->GetSuperClass());
4953 for (int i = klass->GetSuperClass()->GetVTableLength() - 1; i >= 0; --i) {
4954 auto* m = klass->GetVTableEntry(i, image_pointer_size_);
4955 auto* super_m = klass->GetSuperClass()->GetVTableEntry(i, image_pointer_size_);
4957 if (UNLIKELY(!HasSameSignatureWithDifferentClassLoaders(self,
4962 self->AssertPendingException();
4968 for (int32_t i = 0; i < klass->GetIfTableCount(); ++i) {
4969 super_klass.Assign(klass->GetIfTable()->GetInterface(i));
4970 if (klass->GetClassLoader() != super_klass->GetClassLoader()) {
4971 uint32_t num_methods = super_klass->NumVirtualMethods();
4972 for (uint32_t j = 0; j < num_methods; ++j) {
4973 auto* m = klass->GetIfTable()->GetMethodArray(i)->GetElementPtrSize<ArtMethod*>(
4974 j, image_pointer_size_);
4975 auto* super_m = super_klass->GetVirtualMethod(j, image_pointer_size_);
4977 if (UNLIKELY(!HasSameSignatureWithDifferentClassLoaders(self,
4982 self->AssertPendingException();
4992 bool ClassLinker::EnsureInitialized(Thread* self,
4993 Handle<mirror::Class> c,
4994 bool can_init_fields,
4995 bool can_init_parents) {
4996 DCHECK(c.Get() != nullptr);
4997 if (c->IsInitialized()) {
4998 EnsureSkipAccessChecksMethods(c, image_pointer_size_);
4999 self->AssertNoPendingException();
5002 const bool success = InitializeClass(self, c, can_init_fields, can_init_parents);
5004 if (can_init_fields && can_init_parents) {
5005 CHECK(self->IsExceptionPending()) << c->PrettyClass();
5008 self->AssertNoPendingException();
5013 void ClassLinker::FixupTemporaryDeclaringClass(ObjPtr<mirror::Class> temp_class,
5014 ObjPtr<mirror::Class> new_class) {
5015 DCHECK_EQ(temp_class->NumInstanceFields(), 0u);
5016 for (ArtField& field : new_class->GetIFields()) {
5017 if (field.GetDeclaringClass() == temp_class) {
5018 field.SetDeclaringClass(new_class);
5022 DCHECK_EQ(temp_class->NumStaticFields(), 0u);
5023 for (ArtField& field : new_class->GetSFields()) {
5024 if (field.GetDeclaringClass() == temp_class) {
5025 field.SetDeclaringClass(new_class);
5029 DCHECK_EQ(temp_class->NumDirectMethods(), 0u);
5030 DCHECK_EQ(temp_class->NumVirtualMethods(), 0u);
5031 for (auto& method : new_class->GetMethods(image_pointer_size_)) {
5032 if (method.GetDeclaringClass() == temp_class) {
5033 method.SetDeclaringClass(new_class);
5037 // Make sure the remembered set and mod-union tables know that we updated some of the native
5039 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(new_class);
5042 void ClassLinker::RegisterClassLoader(ObjPtr<mirror::ClassLoader> class_loader) {
5043 CHECK(class_loader->GetAllocator() == nullptr);
5044 CHECK(class_loader->GetClassTable() == nullptr);
5045 Thread* const self = Thread::Current();
5046 ClassLoaderData data;
5047 data.weak_root = self->GetJniEnv()->vm->AddWeakGlobalRef(self, class_loader);
5048 // Create and set the class table.
5049 data.class_table = new ClassTable;
5050 class_loader->SetClassTable(data.class_table);
5051 // Create and set the linear allocator.
5052 data.allocator = Runtime::Current()->CreateLinearAlloc();
5053 class_loader->SetAllocator(data.allocator);
5054 // Add to the list so that we know to free the data later.
5055 class_loaders_.push_back(data);
5058 ClassTable* ClassLinker::InsertClassTableForClassLoader(ObjPtr<mirror::ClassLoader> class_loader) {
5059 if (class_loader == nullptr) {
5060 return &boot_class_table_;
5062 ClassTable* class_table = class_loader->GetClassTable();
5063 if (class_table == nullptr) {
5064 RegisterClassLoader(class_loader);
5065 class_table = class_loader->GetClassTable();
5066 DCHECK(class_table != nullptr);
5071 ClassTable* ClassLinker::ClassTableForClassLoader(ObjPtr<mirror::ClassLoader> class_loader) {
5072 return class_loader == nullptr ? &boot_class_table_ : class_loader->GetClassTable();
5075 static ImTable* FindSuperImt(ObjPtr<mirror::Class> klass, PointerSize pointer_size)
5076 REQUIRES_SHARED(Locks::mutator_lock_) {
5077 while (klass->HasSuperClass()) {
5078 klass = klass->GetSuperClass();
5079 if (klass->ShouldHaveImt()) {
5080 return klass->GetImt(pointer_size);
5086 bool ClassLinker::LinkClass(Thread* self,
5087 const char* descriptor,
5088 Handle<mirror::Class> klass,
5089 Handle<mirror::ObjectArray<mirror::Class>> interfaces,
5090 MutableHandle<mirror::Class>* h_new_class_out) {
5091 CHECK_EQ(mirror::Class::kStatusLoaded, klass->GetStatus());
5093 if (!LinkSuperClass(klass)) {
5096 ArtMethod* imt_data[ImTable::kSize];
5097 // If there are any new conflicts compared to super class.
5098 bool new_conflict = false;
5099 std::fill_n(imt_data, arraysize(imt_data), Runtime::Current()->GetImtUnimplementedMethod());
5100 if (!LinkMethods(self, klass, interfaces, &new_conflict, imt_data)) {
5103 if (!LinkInstanceFields(self, klass)) {
5107 if (!LinkStaticFields(self, klass, &class_size)) {
5110 CreateReferenceInstanceOffsets(klass);
5111 CHECK_EQ(mirror::Class::kStatusLoaded, klass->GetStatus());
5113 ImTable* imt = nullptr;
5114 if (klass->ShouldHaveImt()) {
5115 // If there are any new conflicts compared to the super class we can not make a copy. There
5116 // can be cases where both will have a conflict method at the same slot without having the same
5117 // set of conflicts. In this case, we can not share the IMT since the conflict table slow path
5118 // will possibly create a table that is incorrect for either of the classes.
5119 // Same IMT with new_conflict does not happen very often.
5120 if (!new_conflict) {
5121 ImTable* super_imt = FindSuperImt(klass.Get(), image_pointer_size_);
5122 if (super_imt != nullptr) {
5123 bool imt_equals = true;
5124 for (size_t i = 0; i < ImTable::kSize && imt_equals; ++i) {
5125 imt_equals = imt_equals && (super_imt->Get(i, image_pointer_size_) == imt_data[i]);
5132 if (imt == nullptr) {
5133 LinearAlloc* allocator = GetAllocatorForClassLoader(klass->GetClassLoader());
5134 imt = reinterpret_cast<ImTable*>(
5135 allocator->Alloc(self, ImTable::SizeInBytes(image_pointer_size_)));
5136 if (imt == nullptr) {
5139 imt->Populate(imt_data, image_pointer_size_);
5143 if (!klass->IsTemp() || (!init_done_ && klass->GetClassSize() == class_size)) {
5144 // We don't need to retire this class as it has no embedded tables or it was created the
5145 // correct size during class linker initialization.
5146 CHECK_EQ(klass->GetClassSize(), class_size) << klass->PrettyDescriptor();
5148 if (klass->ShouldHaveEmbeddedVTable()) {
5149 klass->PopulateEmbeddedVTable(image_pointer_size_);
5151 if (klass->ShouldHaveImt()) {
5152 klass->SetImt(imt, image_pointer_size_);
5155 // Update CHA info based on whether we override methods.
5156 // Have to do this before setting the class as resolved which allows
5157 // instantiation of klass.
5158 Runtime::Current()->GetClassHierarchyAnalysis()->UpdateAfterLoadingOf(klass);
5160 // This will notify waiters on klass that saw the not yet resolved
5161 // class in the class_table_ during EnsureResolved.
5162 mirror::Class::SetStatus(klass, mirror::Class::kStatusResolved, self);
5163 h_new_class_out->Assign(klass.Get());
5165 CHECK(!klass->IsResolved());
5166 // Retire the temporary class and create the correctly sized resolved class.
5167 StackHandleScope<1> hs(self);
5168 auto h_new_class = hs.NewHandle(klass->CopyOf(self, class_size, imt, image_pointer_size_));
5169 // Set arrays to null since we don't want to have multiple classes with the same ArtField or
5170 // ArtMethod array pointers. If this occurs, it causes bugs in remembered sets since the GC
5171 // may not see any references to the target space and clean the card for a class if another
5172 // class had the same array pointer.
5173 klass->SetMethodsPtrUnchecked(nullptr, 0, 0);
5174 klass->SetSFieldsPtrUnchecked(nullptr);
5175 klass->SetIFieldsPtrUnchecked(nullptr);
5176 if (UNLIKELY(h_new_class.Get() == nullptr)) {
5177 self->AssertPendingOOMException();
5178 mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorUnresolved, self);
5182 CHECK_EQ(h_new_class->GetClassSize(), class_size);
5183 ObjectLock<mirror::Class> lock(self, h_new_class);
5184 FixupTemporaryDeclaringClass(klass.Get(), h_new_class.Get());
5187 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_);
5188 ObjPtr<mirror::ClassLoader> const class_loader = h_new_class.Get()->GetClassLoader();
5189 ClassTable* const table = InsertClassTableForClassLoader(class_loader);
5190 ObjPtr<mirror::Class> existing = table->UpdateClass(descriptor, h_new_class.Get(),
5191 ComputeModifiedUtf8Hash(descriptor));
5192 if (class_loader != nullptr) {
5193 // We updated the class in the class table, perform the write barrier so that the GC knows
5194 // about the change.
5195 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(class_loader);
5197 CHECK_EQ(existing, klass.Get());
5198 if (log_new_roots_) {
5199 new_class_roots_.push_back(GcRoot<mirror::Class>(h_new_class.Get()));
5203 // Update CHA info based on whether we override methods.
5204 // Have to do this before setting the class as resolved which allows
5205 // instantiation of klass.
5206 Runtime::Current()->GetClassHierarchyAnalysis()->UpdateAfterLoadingOf(h_new_class);
5208 // This will notify waiters on temp class that saw the not yet resolved class in the
5209 // class_table_ during EnsureResolved.
5210 mirror::Class::SetStatus(klass, mirror::Class::kStatusRetired, self);
5212 CHECK_EQ(h_new_class->GetStatus(), mirror::Class::kStatusResolving);
5213 // This will notify waiters on new_class that saw the not yet resolved
5214 // class in the class_table_ during EnsureResolved.
5215 mirror::Class::SetStatus(h_new_class, mirror::Class::kStatusResolved, self);
5216 // Return the new class.
5217 h_new_class_out->Assign(h_new_class.Get());
5222 static void CountMethodsAndFields(ClassDataItemIterator& dex_data,
5223 size_t* virtual_methods,
5224 size_t* direct_methods,
5225 size_t* static_fields,
5226 size_t* instance_fields) {
5227 *virtual_methods = *direct_methods = *static_fields = *instance_fields = 0;
5229 while (dex_data.HasNextStaticField()) {
5233 while (dex_data.HasNextInstanceField()) {
5235 (*instance_fields)++;
5237 while (dex_data.HasNextDirectMethod()) {
5238 (*direct_methods)++;
5241 while (dex_data.HasNextVirtualMethod()) {
5242 (*virtual_methods)++;
5245 DCHECK(!dex_data.HasNext());
5248 static void DumpClass(std::ostream& os,
5249 const DexFile& dex_file, const DexFile::ClassDef& dex_class_def,
5250 const char* suffix) {
5251 ClassDataItemIterator dex_data(dex_file, dex_file.GetClassData(dex_class_def));
5252 os << dex_file.GetClassDescriptor(dex_class_def) << suffix << ":\n";
5253 os << " Static fields:\n";
5254 while (dex_data.HasNextStaticField()) {
5255 const DexFile::FieldId& id = dex_file.GetFieldId(dex_data.GetMemberIndex());
5256 os << " " << dex_file.GetFieldTypeDescriptor(id) << " " << dex_file.GetFieldName(id) << "\n";
5259 os << " Instance fields:\n";
5260 while (dex_data.HasNextInstanceField()) {
5261 const DexFile::FieldId& id = dex_file.GetFieldId(dex_data.GetMemberIndex());
5262 os << " " << dex_file.GetFieldTypeDescriptor(id) << " " << dex_file.GetFieldName(id) << "\n";
5265 os << " Direct methods:\n";
5266 while (dex_data.HasNextDirectMethod()) {
5267 const DexFile::MethodId& id = dex_file.GetMethodId(dex_data.GetMemberIndex());
5268 os << " " << dex_file.GetMethodName(id) << dex_file.GetMethodSignature(id).ToString() << "\n";
5271 os << " Virtual methods:\n";
5272 while (dex_data.HasNextVirtualMethod()) {
5273 const DexFile::MethodId& id = dex_file.GetMethodId(dex_data.GetMemberIndex());
5274 os << " " << dex_file.GetMethodName(id) << dex_file.GetMethodSignature(id).ToString() << "\n";
5279 static std::string DumpClasses(const DexFile& dex_file1,
5280 const DexFile::ClassDef& dex_class_def1,
5281 const DexFile& dex_file2,
5282 const DexFile::ClassDef& dex_class_def2) {
5283 std::ostringstream os;
5284 DumpClass(os, dex_file1, dex_class_def1, " (Compile time)");
5285 DumpClass(os, dex_file2, dex_class_def2, " (Runtime)");
5290 // Very simple structural check on whether the classes match. Only compares the number of
5291 // methods and fields.
5292 static bool SimpleStructuralCheck(const DexFile& dex_file1,
5293 const DexFile::ClassDef& dex_class_def1,
5294 const DexFile& dex_file2,
5295 const DexFile::ClassDef& dex_class_def2,
5296 std::string* error_msg) {
5297 ClassDataItemIterator dex_data1(dex_file1, dex_file1.GetClassData(dex_class_def1));
5298 ClassDataItemIterator dex_data2(dex_file2, dex_file2.GetClassData(dex_class_def2));
5300 // Counters for current dex file.
5301 size_t dex_virtual_methods1, dex_direct_methods1, dex_static_fields1, dex_instance_fields1;
5302 CountMethodsAndFields(dex_data1,
5303 &dex_virtual_methods1,
5304 &dex_direct_methods1,
5305 &dex_static_fields1,
5306 &dex_instance_fields1);
5307 // Counters for compile-time dex file.
5308 size_t dex_virtual_methods2, dex_direct_methods2, dex_static_fields2, dex_instance_fields2;
5309 CountMethodsAndFields(dex_data2,
5310 &dex_virtual_methods2,
5311 &dex_direct_methods2,
5312 &dex_static_fields2,
5313 &dex_instance_fields2);
5315 if (dex_virtual_methods1 != dex_virtual_methods2) {
5316 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2);
5317 *error_msg = StringPrintf("Virtual method count off: %zu vs %zu\n%s",
5318 dex_virtual_methods1,
5319 dex_virtual_methods2,
5320 class_dump.c_str());
5323 if (dex_direct_methods1 != dex_direct_methods2) {
5324 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2);
5325 *error_msg = StringPrintf("Direct method count off: %zu vs %zu\n%s",
5326 dex_direct_methods1,
5327 dex_direct_methods2,
5328 class_dump.c_str());
5331 if (dex_static_fields1 != dex_static_fields2) {
5332 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2);
5333 *error_msg = StringPrintf("Static field count off: %zu vs %zu\n%s",
5336 class_dump.c_str());
5339 if (dex_instance_fields1 != dex_instance_fields2) {
5340 std::string class_dump = DumpClasses(dex_file1, dex_class_def1, dex_file2, dex_class_def2);
5341 *error_msg = StringPrintf("Instance field count off: %zu vs %zu\n%s",
5342 dex_instance_fields1,
5343 dex_instance_fields2,
5344 class_dump.c_str());
5351 // Checks whether a the super-class changed from what we had at compile-time. This would
5352 // invalidate quickening.
5353 static bool CheckSuperClassChange(Handle<mirror::Class> klass,
5354 const DexFile& dex_file,
5355 const DexFile::ClassDef& class_def,
5356 ObjPtr<mirror::Class> super_class)
5357 REQUIRES_SHARED(Locks::mutator_lock_) {
5358 // Check for unexpected changes in the superclass.
5359 // Quick check 1) is the super_class class-loader the boot class loader? This always has
5361 if (super_class->GetClassLoader() != nullptr &&
5362 // Quick check 2) different dex cache? Breaks can only occur for different dex files,
5363 // which is implied by different dex cache.
5364 klass->GetDexCache() != super_class->GetDexCache()) {
5365 // Now comes the expensive part: things can be broken if (a) the klass' dex file has a
5366 // definition for the super-class, and (b) the files are in separate oat files. The oat files
5367 // are referenced from the dex file, so do (b) first. Only relevant if we have oat files.
5368 const OatDexFile* class_oat_dex_file = dex_file.GetOatDexFile();
5369 const OatFile* class_oat_file = nullptr;
5370 if (class_oat_dex_file != nullptr) {
5371 class_oat_file = class_oat_dex_file->GetOatFile();
5374 if (class_oat_file != nullptr) {
5375 const OatDexFile* loaded_super_oat_dex_file = super_class->GetDexFile().GetOatDexFile();
5376 const OatFile* loaded_super_oat_file = nullptr;
5377 if (loaded_super_oat_dex_file != nullptr) {
5378 loaded_super_oat_file = loaded_super_oat_dex_file->GetOatFile();
5381 if (loaded_super_oat_file != nullptr && class_oat_file != loaded_super_oat_file) {
5383 const DexFile::ClassDef* super_class_def = dex_file.FindClassDef(class_def.superclass_idx_);
5384 if (super_class_def != nullptr) {
5385 // Uh-oh, we found something. Do our check.
5386 std::string error_msg;
5387 if (!SimpleStructuralCheck(dex_file, *super_class_def,
5388 super_class->GetDexFile(), *super_class->GetClassDef(),
5390 // Print a warning to the log. This exception might be caught, e.g., as common in test
5391 // drivers. When the class is later tried to be used, we re-throw a new instance, as we
5392 // only save the type of the exception.
5393 LOG(WARNING) << "Incompatible structural change detected: " <<
5395 "Structural change of %s is hazardous (%s at compile time, %s at runtime): %s",
5396 dex_file.PrettyType(super_class_def->class_idx_).c_str(),
5397 class_oat_file->GetLocation().c_str(),
5398 loaded_super_oat_file->GetLocation().c_str(),
5400 ThrowIncompatibleClassChangeError(klass.Get(),
5401 "Structural change of %s is hazardous (%s at compile time, %s at runtime): %s",
5402 dex_file.PrettyType(super_class_def->class_idx_).c_str(),
5403 class_oat_file->GetLocation().c_str(),
5404 loaded_super_oat_file->GetLocation().c_str(),
5415 bool ClassLinker::LoadSuperAndInterfaces(Handle<mirror::Class> klass, const DexFile& dex_file) {
5416 CHECK_EQ(mirror::Class::kStatusIdx, klass->GetStatus());
5417 const DexFile::ClassDef& class_def = dex_file.GetClassDef(klass->GetDexClassDefIndex());
5418 dex::TypeIndex super_class_idx = class_def.superclass_idx_;
5419 if (super_class_idx.IsValid()) {
5420 // Check that a class does not inherit from itself directly.
5422 // TODO: This is a cheap check to detect the straightforward case
5423 // of a class extending itself (b/28685551), but we should do a
5424 // proper cycle detection on loaded classes, to detect all cases
5425 // of class circularity errors (b/28830038).
5426 if (super_class_idx == class_def.class_idx_) {
5427 ThrowClassCircularityError(klass.Get(),
5428 "Class %s extends itself",
5429 klass->PrettyDescriptor().c_str());
5433 ObjPtr<mirror::Class> super_class = ResolveType(dex_file, super_class_idx, klass.Get());
5434 if (super_class == nullptr) {
5435 DCHECK(Thread::Current()->IsExceptionPending());
5439 if (!klass->CanAccess(super_class)) {
5440 ThrowIllegalAccessError(klass.Get(), "Class %s extended by class %s is inaccessible",
5441 super_class->PrettyDescriptor().c_str(),
5442 klass->PrettyDescriptor().c_str());
5445 CHECK(super_class->IsResolved());
5446 klass->SetSuperClass(super_class);
5448 if (!CheckSuperClassChange(klass, dex_file, class_def, super_class)) {
5449 DCHECK(Thread::Current()->IsExceptionPending());
5453 const DexFile::TypeList* interfaces = dex_file.GetInterfacesList(class_def);
5454 if (interfaces != nullptr) {
5455 for (size_t i = 0; i < interfaces->Size(); i++) {
5456 dex::TypeIndex idx = interfaces->GetTypeItem(i).type_idx_;
5457 ObjPtr<mirror::Class> interface = ResolveType(dex_file, idx, klass.Get());
5458 if (interface == nullptr) {
5459 DCHECK(Thread::Current()->IsExceptionPending());
5463 if (!klass->CanAccess(interface)) {
5464 // TODO: the RI seemed to ignore this in my testing.
5465 ThrowIllegalAccessError(klass.Get(),
5466 "Interface %s implemented by class %s is inaccessible",
5467 interface->PrettyDescriptor().c_str(),
5468 klass->PrettyDescriptor().c_str());
5473 // Mark the class as loaded.
5474 mirror::Class::SetStatus(klass, mirror::Class::kStatusLoaded, nullptr);
5478 bool ClassLinker::LinkSuperClass(Handle<mirror::Class> klass) {
5479 CHECK(!klass->IsPrimitive());
5480 ObjPtr<mirror::Class> super = klass->GetSuperClass();
5481 if (klass.Get() == GetClassRoot(kJavaLangObject)) {
5482 if (super != nullptr) {
5483 ThrowClassFormatError(klass.Get(), "java.lang.Object must not have a superclass");
5488 if (super == nullptr) {
5489 ThrowLinkageError(klass.Get(), "No superclass defined for class %s",
5490 klass->PrettyDescriptor().c_str());
5494 if (super->IsFinal() || super->IsInterface()) {
5495 ThrowIncompatibleClassChangeError(klass.Get(),
5496 "Superclass %s of %s is %s",
5497 super->PrettyDescriptor().c_str(),
5498 klass->PrettyDescriptor().c_str(),
5499 super->IsFinal() ? "declared final" : "an interface");
5502 if (!klass->CanAccess(super)) {
5503 ThrowIllegalAccessError(klass.Get(), "Superclass %s is inaccessible to class %s",
5504 super->PrettyDescriptor().c_str(),
5505 klass->PrettyDescriptor().c_str());
5509 // Inherit kAccClassIsFinalizable from the superclass in case this
5510 // class doesn't override finalize.
5511 if (super->IsFinalizable()) {
5512 klass->SetFinalizable();
5515 // Inherit class loader flag form super class.
5516 if (super->IsClassLoaderClass()) {
5517 klass->SetClassLoaderClass();
5520 // Inherit reference flags (if any) from the superclass.
5521 uint32_t reference_flags = (super->GetClassFlags() & mirror::kClassFlagReference);
5522 if (reference_flags != 0) {
5523 CHECK_EQ(klass->GetClassFlags(), 0u);
5524 klass->SetClassFlags(klass->GetClassFlags() | reference_flags);
5526 // Disallow custom direct subclasses of java.lang.ref.Reference.
5527 if (init_done_ && super == GetClassRoot(kJavaLangRefReference)) {
5528 ThrowLinkageError(klass.Get(),
5529 "Class %s attempts to subclass java.lang.ref.Reference, which is not allowed",
5530 klass->PrettyDescriptor().c_str());
5534 if (kIsDebugBuild) {
5535 // Ensure super classes are fully resolved prior to resolving fields..
5536 while (super != nullptr) {
5537 CHECK(super->IsResolved());
5538 super = super->GetSuperClass();
5544 // Populate the class vtable and itable. Compute return type indices.
5545 bool ClassLinker::LinkMethods(Thread* self,
5546 Handle<mirror::Class> klass,
5547 Handle<mirror::ObjectArray<mirror::Class>> interfaces,
5548 bool* out_new_conflict,
5549 ArtMethod** out_imt) {
5550 self->AllowThreadSuspension();
5551 // A map from vtable indexes to the method they need to be updated to point to. Used because we
5552 // need to have default methods be in the virtuals array of each class but we don't set that up
5553 // until LinkInterfaceMethods.
5554 std::unordered_map<size_t, ClassLinker::MethodTranslation> default_translations;
5555 // Link virtual methods then interface methods.
5556 // We set up the interface lookup table first because we need it to determine if we need to update
5557 // any vtable entries with new default method implementations.
5558 return SetupInterfaceLookupTable(self, klass, interfaces)
5559 && LinkVirtualMethods(self, klass, /*out*/ &default_translations)
5560 && LinkInterfaceMethods(self, klass, default_translations, out_new_conflict, out_imt);
5563 // Comparator for name and signature of a method, used in finding overriding methods. Implementation
5564 // avoids the use of handles, if it didn't then rather than compare dex files we could compare dex
5565 // caches in the implementation below.
5566 class MethodNameAndSignatureComparator FINAL : public ValueObject {
5568 explicit MethodNameAndSignatureComparator(ArtMethod* method)
5569 REQUIRES_SHARED(Locks::mutator_lock_) :
5570 dex_file_(method->GetDexFile()), mid_(&dex_file_->GetMethodId(method->GetDexMethodIndex())),
5571 name_(nullptr), name_len_(0) {
5572 DCHECK(!method->IsProxyMethod()) << method->PrettyMethod();
5575 const char* GetName() {
5576 if (name_ == nullptr) {
5577 name_ = dex_file_->StringDataAndUtf16LengthByIdx(mid_->name_idx_, &name_len_);
5582 bool HasSameNameAndSignature(ArtMethod* other)
5583 REQUIRES_SHARED(Locks::mutator_lock_) {
5584 DCHECK(!other->IsProxyMethod()) << other->PrettyMethod();
5585 const DexFile* other_dex_file = other->GetDexFile();
5586 const DexFile::MethodId& other_mid = other_dex_file->GetMethodId(other->GetDexMethodIndex());
5587 if (dex_file_ == other_dex_file) {
5588 return mid_->name_idx_ == other_mid.name_idx_ && mid_->proto_idx_ == other_mid.proto_idx_;
5590 GetName(); // Only used to make sure its calculated.
5591 uint32_t other_name_len;
5592 const char* other_name = other_dex_file->StringDataAndUtf16LengthByIdx(other_mid.name_idx_,
5594 if (name_len_ != other_name_len || strcmp(name_, other_name) != 0) {
5597 return dex_file_->GetMethodSignature(*mid_) == other_dex_file->GetMethodSignature(other_mid);
5601 // Dex file for the method to compare against.
5602 const DexFile* const dex_file_;
5603 // MethodId for the method to compare against.
5604 const DexFile::MethodId* const mid_;
5605 // Lazily computed name from the dex file's strings.
5607 // Lazily computed name length.
5611 class LinkVirtualHashTable {
5613 LinkVirtualHashTable(Handle<mirror::Class> klass,
5615 uint32_t* hash_table,
5616 PointerSize image_pointer_size)
5618 hash_size_(hash_size),
5619 hash_table_(hash_table),
5620 image_pointer_size_(image_pointer_size) {
5621 std::fill(hash_table_, hash_table_ + hash_size_, invalid_index_);
5624 void Add(uint32_t virtual_method_index) REQUIRES_SHARED(Locks::mutator_lock_) {
5625 ArtMethod* local_method = klass_->GetVirtualMethodDuringLinking(
5626 virtual_method_index, image_pointer_size_);
5627 const char* name = local_method->GetInterfaceMethodIfProxy(image_pointer_size_)->GetName();
5628 uint32_t hash = ComputeModifiedUtf8Hash(name);
5629 uint32_t index = hash % hash_size_;
5630 // Linear probe until we have an empty slot.
5631 while (hash_table_[index] != invalid_index_) {
5632 if (++index == hash_size_) {
5636 hash_table_[index] = virtual_method_index;
5639 uint32_t FindAndRemove(MethodNameAndSignatureComparator* comparator)
5640 REQUIRES_SHARED(Locks::mutator_lock_) {
5641 const char* name = comparator->GetName();
5642 uint32_t hash = ComputeModifiedUtf8Hash(name);
5643 size_t index = hash % hash_size_;
5645 const uint32_t value = hash_table_[index];
5646 // Since linear probe makes continuous blocks, hitting an invalid index means we are done
5647 // the block and can safely assume not found.
5648 if (value == invalid_index_) {
5651 if (value != removed_index_) { // This signifies not already overriden.
5652 ArtMethod* virtual_method =
5653 klass_->GetVirtualMethodDuringLinking(value, image_pointer_size_);
5654 if (comparator->HasSameNameAndSignature(
5655 virtual_method->GetInterfaceMethodIfProxy(image_pointer_size_))) {
5656 hash_table_[index] = removed_index_;
5660 if (++index == hash_size_) {
5664 return GetNotFoundIndex();
5667 static uint32_t GetNotFoundIndex() {
5668 return invalid_index_;
5672 static const uint32_t invalid_index_;
5673 static const uint32_t removed_index_;
5675 Handle<mirror::Class> klass_;
5676 const size_t hash_size_;
5677 uint32_t* const hash_table_;
5678 const PointerSize image_pointer_size_;
5681 const uint32_t LinkVirtualHashTable::invalid_index_ = std::numeric_limits<uint32_t>::max();
5682 const uint32_t LinkVirtualHashTable::removed_index_ = std::numeric_limits<uint32_t>::max() - 1;
5685 #if defined(__i386__)
5686 #define X86_OPTNONE __attribute__((optnone))
5691 X86_OPTNONE bool ClassLinker::LinkVirtualMethods(
5693 Handle<mirror::Class> klass,
5694 /*out*/std::unordered_map<size_t, ClassLinker::MethodTranslation>* default_translations) {
5695 const size_t num_virtual_methods = klass->NumVirtualMethods();
5696 if (klass->IsInterface()) {
5698 if (!IsUint<16>(num_virtual_methods)) {
5699 ThrowClassFormatError(klass.Get(), "Too many methods on interface: %zu", num_virtual_methods);
5702 bool has_defaults = false;
5703 // Assign each method an IMT index and set the default flag.
5704 for (size_t i = 0; i < num_virtual_methods; ++i) {
5705 ArtMethod* m = klass->GetVirtualMethodDuringLinking(i, image_pointer_size_);
5706 m->SetMethodIndex(i);
5707 if (!m->IsAbstract()) {
5708 m->SetAccessFlags(m->GetAccessFlags() | kAccDefault);
5709 has_defaults = true;
5712 // Mark that we have default methods so that we won't need to scan the virtual_methods_ array
5713 // during initialization. This is a performance optimization. We could simply traverse the
5714 // virtual_methods_ array again during initialization.
5716 klass->SetHasDefaultMethods();
5719 } else if (klass->HasSuperClass()) {
5720 const size_t super_vtable_length = klass->GetSuperClass()->GetVTableLength();
5721 const size_t max_count = num_virtual_methods + super_vtable_length;
5722 StackHandleScope<2> hs(self);
5723 Handle<mirror::Class> super_class(hs.NewHandle(klass->GetSuperClass()));
5724 MutableHandle<mirror::PointerArray> vtable;
5725 if (super_class->ShouldHaveEmbeddedVTable()) {
5726 vtable = hs.NewHandle(AllocPointerArray(self, max_count));
5727 if (UNLIKELY(vtable.Get() == nullptr)) {
5728 self->AssertPendingOOMException();
5731 for (size_t i = 0; i < super_vtable_length; i++) {
5732 vtable->SetElementPtrSize(
5733 i, super_class->GetEmbeddedVTableEntry(i, image_pointer_size_), image_pointer_size_);
5735 // We might need to change vtable if we have new virtual methods or new interfaces (since that
5736 // might give us new default methods). If no new interfaces then we can skip the rest since
5737 // the class cannot override any of the super-class's methods. This is required for
5738 // correctness since without it we might not update overridden default method vtable entries
5740 if (num_virtual_methods == 0 && super_class->GetIfTableCount() == klass->GetIfTableCount()) {
5741 klass->SetVTable(vtable.Get());
5745 DCHECK(super_class->IsAbstract() && !super_class->IsArrayClass());
5746 auto* super_vtable = super_class->GetVTable();
5747 CHECK(super_vtable != nullptr) << super_class->PrettyClass();
5748 // We might need to change vtable if we have new virtual methods or new interfaces (since that
5749 // might give us new default methods). See comment above.
5750 if (num_virtual_methods == 0 && super_class->GetIfTableCount() == klass->GetIfTableCount()) {
5751 klass->SetVTable(super_vtable);
5754 vtable = hs.NewHandle(down_cast<mirror::PointerArray*>(
5755 super_vtable->CopyOf(self, max_count)));
5756 if (UNLIKELY(vtable.Get() == nullptr)) {
5757 self->AssertPendingOOMException();
5761 // How the algorithm works:
5762 // 1. Populate hash table by adding num_virtual_methods from klass. The values in the hash
5763 // table are: invalid_index for unused slots, index super_vtable_length + i for a virtual
5764 // method which has not been matched to a vtable method, and j if the virtual method at the
5765 // index overrode the super virtual method at index j.
5766 // 2. Loop through super virtual methods, if they overwrite, update hash table to j
5767 // (j < super_vtable_length) to avoid redundant checks. (TODO maybe use this info for reducing
5768 // the need for the initial vtable which we later shrink back down).
5769 // 3. Add non overridden methods to the end of the vtable.
5770 static constexpr size_t kMaxStackHash = 250;
5771 // + 1 so that even if we only have new default methods we will still be able to use this hash
5772 // table (i.e. it will never have 0 size).
5773 const size_t hash_table_size = num_virtual_methods * 3 + 1;
5774 uint32_t* hash_table_ptr;
5775 std::unique_ptr<uint32_t[]> hash_heap_storage;
5776 if (hash_table_size <= kMaxStackHash) {
5777 hash_table_ptr = reinterpret_cast<uint32_t*>(
5778 alloca(hash_table_size * sizeof(*hash_table_ptr)));
5780 hash_heap_storage.reset(new uint32_t[hash_table_size]);
5781 hash_table_ptr = hash_heap_storage.get();
5783 LinkVirtualHashTable hash_table(klass, hash_table_size, hash_table_ptr, image_pointer_size_);
5784 // Add virtual methods to the hash table.
5785 for (size_t i = 0; i < num_virtual_methods; ++i) {
5786 DCHECK(klass->GetVirtualMethodDuringLinking(
5787 i, image_pointer_size_)->GetDeclaringClass() != nullptr);
5790 // Loop through each super vtable method and see if they are overridden by a method we added to
5792 for (size_t j = 0; j < super_vtable_length; ++j) {
5793 // Search the hash table to see if we are overridden by any method.
5794 ArtMethod* super_method = vtable->GetElementPtrSize<ArtMethod*>(j, image_pointer_size_);
5795 if (!klass->CanAccessMember(super_method->GetDeclaringClass(),
5796 super_method->GetAccessFlags())) {
5797 // Continue on to the next method since this one is package private and canot be overridden.
5798 // Before Android 4.1, the package-private method super_method might have been incorrectly
5802 MethodNameAndSignatureComparator super_method_name_comparator(
5803 super_method->GetInterfaceMethodIfProxy(image_pointer_size_));
5804 // We remove the method so that subsequent lookups will be faster by making the hash-map
5805 // smaller as we go on.
5806 uint32_t hash_index = hash_table.FindAndRemove(&super_method_name_comparator);
5807 if (hash_index != hash_table.GetNotFoundIndex()) {
5808 ArtMethod* virtual_method = klass->GetVirtualMethodDuringLinking(
5809 hash_index, image_pointer_size_);
5810 if (super_method->IsFinal()) {
5811 ThrowLinkageError(klass.Get(), "Method %s overrides final method in class %s",
5812 virtual_method->PrettyMethod().c_str(),
5813 super_method->GetDeclaringClassDescriptor());
5816 vtable->SetElementPtrSize(j, virtual_method, image_pointer_size_);
5817 virtual_method->SetMethodIndex(j);
5818 } else if (super_method->IsOverridableByDefaultMethod()) {
5819 // We didn't directly override this method but we might through default methods...
5820 // Check for default method update.
5821 ArtMethod* default_method = nullptr;
5822 switch (FindDefaultMethodImplementation(self,
5825 /*out*/&default_method)) {
5826 case DefaultMethodSearchResult::kDefaultConflict: {
5827 // A conflict was found looking for default methods. Note this (assuming it wasn't
5828 // pre-existing) in the translations map.
5829 if (UNLIKELY(!super_method->IsDefaultConflicting())) {
5830 // Don't generate another conflict method to reduce memory use as an optimization.
5831 default_translations->insert(
5832 {j, ClassLinker::MethodTranslation::CreateConflictingMethod()});
5836 case DefaultMethodSearchResult::kAbstractFound: {
5837 // No conflict but method is abstract.
5838 // We note that this vtable entry must be made abstract.
5839 if (UNLIKELY(!super_method->IsAbstract())) {
5840 default_translations->insert(
5841 {j, ClassLinker::MethodTranslation::CreateAbstractMethod()});
5845 case DefaultMethodSearchResult::kDefaultFound: {
5846 if (UNLIKELY(super_method->IsDefaultConflicting() ||
5847 default_method->GetDeclaringClass() != super_method->GetDeclaringClass())) {
5848 // Found a default method implementation that is new.
5849 // TODO Refactor this add default methods to virtuals here and not in
5850 // LinkInterfaceMethods maybe.
5851 // The problem is default methods might override previously present
5852 // default-method or miranda-method vtable entries from the superclass.
5853 // Unfortunately we need these to be entries in this class's virtuals. We do not
5854 // give these entries there until LinkInterfaceMethods so we pass this map around
5855 // to let it know which vtable entries need to be updated.
5856 // Make a note that vtable entry j must be updated, store what it needs to be updated
5857 // to. We will allocate a virtual method slot in LinkInterfaceMethods and fix it up
5859 default_translations->insert(
5860 {j, ClassLinker::MethodTranslation::CreateTranslatedMethod(default_method)});
5861 VLOG(class_linker) << "Method " << super_method->PrettyMethod()
5862 << " overridden by default "
5863 << default_method->PrettyMethod()
5864 << " in " << mirror::Class::PrettyClass(klass.Get());
5871 size_t actual_count = super_vtable_length;
5872 // Add the non-overridden methods at the end.
5873 for (size_t i = 0; i < num_virtual_methods; ++i) {
5874 ArtMethod* local_method = klass->GetVirtualMethodDuringLinking(i, image_pointer_size_);
5875 size_t method_idx = local_method->GetMethodIndexDuringLinking();
5876 if (method_idx < super_vtable_length &&
5877 local_method == vtable->GetElementPtrSize<ArtMethod*>(method_idx, image_pointer_size_)) {
5880 vtable->SetElementPtrSize(actual_count, local_method, image_pointer_size_);
5881 local_method->SetMethodIndex(actual_count);
5884 if (!IsUint<16>(actual_count)) {
5885 ThrowClassFormatError(klass.Get(), "Too many methods defined on class: %zd", actual_count);
5888 // Shrink vtable if possible
5889 CHECK_LE(actual_count, max_count);
5890 if (actual_count < max_count) {
5891 vtable.Assign(down_cast<mirror::PointerArray*>(vtable->CopyOf(self, actual_count)));
5892 if (UNLIKELY(vtable.Get() == nullptr)) {
5893 self->AssertPendingOOMException();
5897 klass->SetVTable(vtable.Get());
5899 CHECK_EQ(klass.Get(), GetClassRoot(kJavaLangObject));
5900 if (!IsUint<16>(num_virtual_methods)) {
5901 ThrowClassFormatError(klass.Get(), "Too many methods: %d",
5902 static_cast<int>(num_virtual_methods));
5905 auto* vtable = AllocPointerArray(self, num_virtual_methods);
5906 if (UNLIKELY(vtable == nullptr)) {
5907 self->AssertPendingOOMException();
5910 for (size_t i = 0; i < num_virtual_methods; ++i) {
5911 ArtMethod* virtual_method = klass->GetVirtualMethodDuringLinking(i, image_pointer_size_);
5912 vtable->SetElementPtrSize(i, virtual_method, image_pointer_size_);
5913 virtual_method->SetMethodIndex(i & 0xFFFF);
5915 klass->SetVTable(vtable);
5920 // Determine if the given iface has any subinterface in the given list that declares the method
5921 // specified by 'target'.
5924 // - self: The thread we are running on
5925 // - target: A comparator that will match any method that overrides the method we are checking for
5926 // - iftable: The iftable we are searching for an overriding method on.
5927 // - ifstart: The index of the interface we are checking to see if anything overrides
5928 // - iface: The interface we are checking to see if anything overrides.
5929 // - image_pointer_size:
5930 // The image pointer size.
5933 // - True: There is some method that matches the target comparator defined in an interface that
5934 // is a subtype of iface.
5935 // - False: There is no method that matches the target comparator in any interface that is a subtype
5937 static bool ContainsOverridingMethodOf(Thread* self,
5938 MethodNameAndSignatureComparator& target,
5939 Handle<mirror::IfTable> iftable,
5941 Handle<mirror::Class> iface,
5942 PointerSize image_pointer_size)
5943 REQUIRES_SHARED(Locks::mutator_lock_) {
5944 DCHECK(self != nullptr);
5945 DCHECK(iface.Get() != nullptr);
5946 DCHECK(iftable.Get() != nullptr);
5947 DCHECK_GE(ifstart, 0u);
5948 DCHECK_LT(ifstart, iftable->Count());
5949 DCHECK_EQ(iface.Get(), iftable->GetInterface(ifstart));
5950 DCHECK(iface->IsInterface());
5952 size_t iftable_count = iftable->Count();
5953 StackHandleScope<1> hs(self);
5954 MutableHandle<mirror::Class> current_iface(hs.NewHandle<mirror::Class>(nullptr));
5955 for (size_t k = ifstart + 1; k < iftable_count; k++) {
5956 // Skip ifstart since our current interface obviously cannot override itself.
5957 current_iface.Assign(iftable->GetInterface(k));
5958 // Iterate through every method on this interface. The order does not matter.
5959 for (ArtMethod& current_method : current_iface->GetDeclaredVirtualMethods(image_pointer_size)) {
5960 if (UNLIKELY(target.HasSameNameAndSignature(
5961 current_method.GetInterfaceMethodIfProxy(image_pointer_size)))) {
5962 // Check if the i'th interface is a subtype of this one.
5963 if (iface->IsAssignableFrom(current_iface.Get())) {
5973 // Find the default method implementation for 'interface_method' in 'klass'. Stores it into
5974 // out_default_method and returns kDefaultFound on success. If no default method was found return
5975 // kAbstractFound and store nullptr into out_default_method. If an error occurs (such as a
5976 // default_method conflict) it will return kDefaultConflict.
5977 ClassLinker::DefaultMethodSearchResult ClassLinker::FindDefaultMethodImplementation(
5979 ArtMethod* target_method,
5980 Handle<mirror::Class> klass,
5981 /*out*/ArtMethod** out_default_method) const {
5982 DCHECK(self != nullptr);
5983 DCHECK(target_method != nullptr);
5984 DCHECK(out_default_method != nullptr);
5986 *out_default_method = nullptr;
5988 // We organize the interface table so that, for interface I any subinterfaces J follow it in the
5989 // table. This lets us walk the table backwards when searching for default methods. The first one
5990 // we encounter is the best candidate since it is the most specific. Once we have found it we keep
5991 // track of it and then continue checking all other interfaces, since we need to throw an error if
5992 // we encounter conflicting default method implementations (one is not a subtype of the other).
5994 // The order of unrelated interfaces does not matter and is not defined.
5995 size_t iftable_count = klass->GetIfTableCount();
5996 if (iftable_count == 0) {
5997 // No interfaces. We have already reset out to null so just return kAbstractFound.
5998 return DefaultMethodSearchResult::kAbstractFound;
6001 StackHandleScope<3> hs(self);
6002 MutableHandle<mirror::Class> chosen_iface(hs.NewHandle<mirror::Class>(nullptr));
6003 MutableHandle<mirror::IfTable> iftable(hs.NewHandle(klass->GetIfTable()));
6004 MutableHandle<mirror::Class> iface(hs.NewHandle<mirror::Class>(nullptr));
6005 MethodNameAndSignatureComparator target_name_comparator(
6006 target_method->GetInterfaceMethodIfProxy(image_pointer_size_));
6007 // Iterates over the klass's iftable in reverse
6008 for (size_t k = iftable_count; k != 0; ) {
6011 DCHECK_LT(k, iftable->Count());
6013 iface.Assign(iftable->GetInterface(k));
6014 // Iterate through every declared method on this interface. The order does not matter.
6015 for (auto& method_iter : iface->GetDeclaredVirtualMethods(image_pointer_size_)) {
6016 ArtMethod* current_method = &method_iter;
6017 // Skip abstract methods and methods with different names.
6018 if (current_method->IsAbstract() ||
6019 !target_name_comparator.HasSameNameAndSignature(
6020 current_method->GetInterfaceMethodIfProxy(image_pointer_size_))) {
6022 } else if (!current_method->IsPublic()) {
6023 // The verifier should have caught the non-public method for dex version 37. Just warn and
6024 // skip it since this is from before default-methods so we don't really need to care that it
6026 LOG(WARNING) << "Interface method " << current_method->PrettyMethod()
6027 << " is not public! "
6028 << "This will be a fatal error in subsequent versions of android. "
6029 << "Continuing anyway.";
6031 if (UNLIKELY(chosen_iface.Get() != nullptr)) {
6032 // We have multiple default impls of the same method. This is a potential default conflict.
6033 // We need to check if this possibly conflicting method is either a superclass of the chosen
6034 // default implementation or is overridden by a non-default interface method. In either case
6035 // there is no conflict.
6036 if (!iface->IsAssignableFrom(chosen_iface.Get()) &&
6037 !ContainsOverridingMethodOf(self,
6038 target_name_comparator,
6042 image_pointer_size_)) {
6043 VLOG(class_linker) << "Conflicting default method implementations found: "
6044 << current_method->PrettyMethod() << " and "
6045 << ArtMethod::PrettyMethod(*out_default_method) << " in class "
6046 << klass->PrettyClass() << " conflict.";
6047 *out_default_method = nullptr;
6048 return DefaultMethodSearchResult::kDefaultConflict;
6050 break; // Continue checking at the next interface.
6053 // chosen_iface == null
6054 if (!ContainsOverridingMethodOf(self,
6055 target_name_comparator,
6059 image_pointer_size_)) {
6060 // Don't set this as the chosen interface if something else is overriding it (because that
6061 // other interface would be potentially chosen instead if it was default). If the other
6062 // interface was abstract then we wouldn't select this interface as chosen anyway since
6063 // the abstract method masks it.
6064 *out_default_method = current_method;
6065 chosen_iface.Assign(iface.Get());
6066 // We should now finish traversing the graph to find if we have default methods that
6069 VLOG(class_linker) << "A default method '" << current_method->PrettyMethod()
6071 << "skipped because it was overridden by an abstract method in a "
6072 << "subinterface on class '" << klass->PrettyClass() << "'";
6078 if (*out_default_method != nullptr) {
6079 VLOG(class_linker) << "Default method '" << (*out_default_method)->PrettyMethod()
6081 << "as the implementation for '" << target_method->PrettyMethod()
6082 << "' in '" << klass->PrettyClass() << "'";
6083 return DefaultMethodSearchResult::kDefaultFound;
6085 return DefaultMethodSearchResult::kAbstractFound;
6089 ArtMethod* ClassLinker::AddMethodToConflictTable(ObjPtr<mirror::Class> klass,
6090 ArtMethod* conflict_method,
6091 ArtMethod* interface_method,
6093 bool force_new_conflict_method) {
6094 ImtConflictTable* current_table = conflict_method->GetImtConflictTable(kRuntimePointerSize);
6095 Runtime* const runtime = Runtime::Current();
6096 LinearAlloc* linear_alloc = GetAllocatorForClassLoader(klass->GetClassLoader());
6097 bool new_entry = conflict_method == runtime->GetImtConflictMethod() || force_new_conflict_method;
6099 // Create a new entry if the existing one is the shared conflict method.
6100 ArtMethod* new_conflict_method = new_entry
6101 ? runtime->CreateImtConflictMethod(linear_alloc)
6104 // Allocate a new table. Note that we will leak this table at the next conflict,
6105 // but that's a tradeoff compared to making the table fixed size.
6106 void* data = linear_alloc->Alloc(
6107 Thread::Current(), ImtConflictTable::ComputeSizeWithOneMoreEntry(current_table,
6108 image_pointer_size_));
6109 if (data == nullptr) {
6110 LOG(ERROR) << "Failed to allocate conflict table";
6111 return conflict_method;
6113 ImtConflictTable* new_table = new (data) ImtConflictTable(current_table,
6116 image_pointer_size_);
6118 // Do a fence to ensure threads see the data in the table before it is assigned
6119 // to the conflict method.
6120 // Note that there is a race in the presence of multiple threads and we may leak
6121 // memory from the LinearAlloc, but that's a tradeoff compared to using
6122 // atomic operations.
6123 QuasiAtomic::ThreadFenceRelease();
6124 new_conflict_method->SetImtConflictTable(new_table, image_pointer_size_);
6125 return new_conflict_method;
6128 bool ClassLinker::AllocateIfTableMethodArrays(Thread* self,
6129 Handle<mirror::Class> klass,
6130 Handle<mirror::IfTable> iftable) {
6131 DCHECK(!klass->IsInterface());
6132 const bool has_superclass = klass->HasSuperClass();
6133 const bool extend_super_iftable = has_superclass;
6134 const size_t ifcount = klass->GetIfTableCount();
6135 const size_t super_ifcount = has_superclass ? klass->GetSuperClass()->GetIfTableCount() : 0U;
6136 for (size_t i = 0; i < ifcount; ++i) {
6137 size_t num_methods = iftable->GetInterface(i)->NumDeclaredVirtualMethods();
6138 if (num_methods > 0) {
6139 const bool is_super = i < super_ifcount;
6140 // This is an interface implemented by a super-class. Therefore we can just copy the method
6141 // array from the superclass.
6142 const bool super_interface = is_super && extend_super_iftable;
6143 ObjPtr<mirror::PointerArray> method_array;
6144 if (super_interface) {
6145 ObjPtr<mirror::IfTable> if_table = klass->GetSuperClass()->GetIfTable();
6146 DCHECK(if_table != nullptr);
6147 DCHECK(if_table->GetMethodArray(i) != nullptr);
6148 // If we are working on a super interface, try extending the existing method array.
6149 method_array = down_cast<mirror::PointerArray*>(if_table->GetMethodArray(i)->Clone(self));
6151 method_array = AllocPointerArray(self, num_methods);
6153 if (UNLIKELY(method_array == nullptr)) {
6154 self->AssertPendingOOMException();
6157 iftable->SetMethodArray(i, method_array);
6163 void ClassLinker::SetIMTRef(ArtMethod* unimplemented_method,
6164 ArtMethod* imt_conflict_method,
6165 ArtMethod* current_method,
6166 /*out*/bool* new_conflict,
6167 /*out*/ArtMethod** imt_ref) {
6168 // Place method in imt if entry is empty, place conflict otherwise.
6169 if (*imt_ref == unimplemented_method) {
6170 *imt_ref = current_method;
6171 } else if (!(*imt_ref)->IsRuntimeMethod()) {
6172 // If we are not a conflict and we have the same signature and name as the imt
6173 // entry, it must be that we overwrote a superclass vtable entry.
6174 // Note that we have checked IsRuntimeMethod, as there may be multiple different
6175 // conflict methods.
6176 MethodNameAndSignatureComparator imt_comparator(
6177 (*imt_ref)->GetInterfaceMethodIfProxy(image_pointer_size_));
6178 if (imt_comparator.HasSameNameAndSignature(
6179 current_method->GetInterfaceMethodIfProxy(image_pointer_size_))) {
6180 *imt_ref = current_method;
6182 *imt_ref = imt_conflict_method;
6183 *new_conflict = true;
6186 // Place the default conflict method. Note that there may be an existing conflict
6187 // method in the IMT, but it could be one tailored to the super class, with a
6188 // specific ImtConflictTable.
6189 *imt_ref = imt_conflict_method;
6190 *new_conflict = true;
6194 void ClassLinker::FillIMTAndConflictTables(ObjPtr<mirror::Class> klass) {
6195 DCHECK(klass->ShouldHaveImt()) << klass->PrettyClass();
6196 DCHECK(!klass->IsTemp()) << klass->PrettyClass();
6197 ArtMethod* imt_data[ImTable::kSize];
6198 Runtime* const runtime = Runtime::Current();
6199 ArtMethod* const unimplemented_method = runtime->GetImtUnimplementedMethod();
6200 ArtMethod* const conflict_method = runtime->GetImtConflictMethod();
6201 std::fill_n(imt_data, arraysize(imt_data), unimplemented_method);
6202 if (klass->GetIfTable() != nullptr) {
6203 bool new_conflict = false;
6204 FillIMTFromIfTable(klass->GetIfTable(),
6205 unimplemented_method,
6208 /*create_conflict_tables*/true,
6209 /*ignore_copied_methods*/false,
6213 if (!klass->ShouldHaveImt()) {
6216 // Compare the IMT with the super class including the conflict methods. If they are equivalent,
6217 // we can just use the same pointer.
6218 ImTable* imt = nullptr;
6219 ObjPtr<mirror::Class> super_class = klass->GetSuperClass();
6220 if (super_class != nullptr && super_class->ShouldHaveImt()) {
6221 ImTable* super_imt = super_class->GetImt(image_pointer_size_);
6223 for (size_t i = 0; same && i < ImTable::kSize; ++i) {
6224 ArtMethod* method = imt_data[i];
6225 ArtMethod* super_method = super_imt->Get(i, image_pointer_size_);
6226 if (method != super_method) {
6227 bool is_conflict_table = method->IsRuntimeMethod() &&
6228 method != unimplemented_method &&
6229 method != conflict_method;
6230 // Verify conflict contents.
6231 bool super_conflict_table = super_method->IsRuntimeMethod() &&
6232 super_method != unimplemented_method &&
6233 super_method != conflict_method;
6234 if (!is_conflict_table || !super_conflict_table) {
6237 ImtConflictTable* table1 = method->GetImtConflictTable(image_pointer_size_);
6238 ImtConflictTable* table2 = super_method->GetImtConflictTable(image_pointer_size_);
6239 same = same && table1->Equals(table2, image_pointer_size_);
6247 if (imt == nullptr) {
6248 imt = klass->GetImt(image_pointer_size_);
6249 DCHECK(imt != nullptr);
6250 imt->Populate(imt_data, image_pointer_size_);
6252 klass->SetImt(imt, image_pointer_size_);
6256 ImtConflictTable* ClassLinker::CreateImtConflictTable(size_t count,
6257 LinearAlloc* linear_alloc,
6258 PointerSize image_pointer_size) {
6259 void* data = linear_alloc->Alloc(Thread::Current(),
6260 ImtConflictTable::ComputeSize(count,
6261 image_pointer_size));
6262 return (data != nullptr) ? new (data) ImtConflictTable(count, image_pointer_size) : nullptr;
6265 ImtConflictTable* ClassLinker::CreateImtConflictTable(size_t count, LinearAlloc* linear_alloc) {
6266 return CreateImtConflictTable(count, linear_alloc, image_pointer_size_);
6269 void ClassLinker::FillIMTFromIfTable(ObjPtr<mirror::IfTable> if_table,
6270 ArtMethod* unimplemented_method,
6271 ArtMethod* imt_conflict_method,
6272 ObjPtr<mirror::Class> klass,
6273 bool create_conflict_tables,
6274 bool ignore_copied_methods,
6275 /*out*/bool* new_conflict,
6276 /*out*/ArtMethod** imt) {
6277 uint32_t conflict_counts[ImTable::kSize] = {};
6278 for (size_t i = 0, length = if_table->Count(); i < length; ++i) {
6279 ObjPtr<mirror::Class> interface = if_table->GetInterface(i);
6280 const size_t num_virtuals = interface->NumVirtualMethods();
6281 const size_t method_array_count = if_table->GetMethodArrayCount(i);
6282 // Virtual methods can be larger than the if table methods if there are default methods.
6283 DCHECK_GE(num_virtuals, method_array_count);
6284 if (kIsDebugBuild) {
6285 if (klass->IsInterface()) {
6286 DCHECK_EQ(method_array_count, 0u);
6288 DCHECK_EQ(interface->NumDeclaredVirtualMethods(), method_array_count);
6291 if (method_array_count == 0) {
6294 auto* method_array = if_table->GetMethodArray(i);
6295 for (size_t j = 0; j < method_array_count; ++j) {
6296 ArtMethod* implementation_method =
6297 method_array->GetElementPtrSize<ArtMethod*>(j, image_pointer_size_);
6298 if (ignore_copied_methods && implementation_method->IsCopied()) {
6301 DCHECK(implementation_method != nullptr);
6302 // Miranda methods cannot be used to implement an interface method, but they are safe to put
6303 // in the IMT since their entrypoint is the interface trampoline. If we put any copied methods
6304 // or interface methods in the IMT here they will not create extra conflicts since we compare
6305 // names and signatures in SetIMTRef.
6306 ArtMethod* interface_method = interface->GetVirtualMethod(j, image_pointer_size_);
6307 const uint32_t imt_index = ImTable::GetImtIndex(interface_method);
6309 // There is only any conflicts if all of the interface methods for an IMT slot don't have
6310 // the same implementation method, keep track of this to avoid creating a conflict table in
6313 // Conflict table size for each IMT slot.
6314 ++conflict_counts[imt_index];
6316 SetIMTRef(unimplemented_method,
6317 imt_conflict_method,
6318 implementation_method,
6319 /*out*/new_conflict,
6320 /*out*/&imt[imt_index]);
6324 if (create_conflict_tables) {
6325 // Create the conflict tables.
6326 LinearAlloc* linear_alloc = GetAllocatorForClassLoader(klass->GetClassLoader());
6327 for (size_t i = 0; i < ImTable::kSize; ++i) {
6328 size_t conflicts = conflict_counts[i];
6329 if (imt[i] == imt_conflict_method) {
6330 ImtConflictTable* new_table = CreateImtConflictTable(conflicts, linear_alloc);
6331 if (new_table != nullptr) {
6332 ArtMethod* new_conflict_method =
6333 Runtime::Current()->CreateImtConflictMethod(linear_alloc);
6334 new_conflict_method->SetImtConflictTable(new_table, image_pointer_size_);
6335 imt[i] = new_conflict_method;
6337 LOG(ERROR) << "Failed to allocate conflict table";
6338 imt[i] = imt_conflict_method;
6341 DCHECK_NE(imt[i], imt_conflict_method);
6345 for (size_t i = 0, length = if_table->Count(); i < length; ++i) {
6346 ObjPtr<mirror::Class> interface = if_table->GetInterface(i);
6347 const size_t method_array_count = if_table->GetMethodArrayCount(i);
6348 // Virtual methods can be larger than the if table methods if there are default methods.
6349 if (method_array_count == 0) {
6352 auto* method_array = if_table->GetMethodArray(i);
6353 for (size_t j = 0; j < method_array_count; ++j) {
6354 ArtMethod* implementation_method =
6355 method_array->GetElementPtrSize<ArtMethod*>(j, image_pointer_size_);
6356 if (ignore_copied_methods && implementation_method->IsCopied()) {
6359 DCHECK(implementation_method != nullptr);
6360 ArtMethod* interface_method = interface->GetVirtualMethod(j, image_pointer_size_);
6361 const uint32_t imt_index = ImTable::GetImtIndex(interface_method);
6362 if (!imt[imt_index]->IsRuntimeMethod() ||
6363 imt[imt_index] == unimplemented_method ||
6364 imt[imt_index] == imt_conflict_method) {
6367 ImtConflictTable* table = imt[imt_index]->GetImtConflictTable(image_pointer_size_);
6368 const size_t num_entries = table->NumEntries(image_pointer_size_);
6369 table->SetInterfaceMethod(num_entries, image_pointer_size_, interface_method);
6370 table->SetImplementationMethod(num_entries, image_pointer_size_, implementation_method);
6376 // Simple helper function that checks that no subtypes of 'val' are contained within the 'classes'
6378 static bool NotSubinterfaceOfAny(
6379 const std::unordered_set<ObjPtr<mirror::Class>, HashObjPtr>& classes,
6380 ObjPtr<mirror::Class> val)
6381 REQUIRES(Roles::uninterruptible_)
6382 REQUIRES_SHARED(Locks::mutator_lock_) {
6383 DCHECK(val != nullptr);
6384 for (ObjPtr<mirror::Class> c : classes) {
6385 if (val->IsAssignableFrom(c)) {
6392 // Fills in and flattens the interface inheritance hierarchy.
6394 // By the end of this function all interfaces in the transitive closure of to_process are added to
6395 // the iftable and every interface precedes all of its sub-interfaces in this list.
6397 // all I, J: Interface | I <: J implies J precedes I
6399 // (note A <: B means that A is a subtype of B)
6401 // This returns the total number of items in the iftable. The iftable might be resized down after
6404 // We order this backwards so that we do not need to reorder superclass interfaces when new
6405 // interfaces are added in subclass's interface tables.
6407 // Upon entry into this function iftable is a copy of the superclass's iftable with the first
6408 // super_ifcount entries filled in with the transitive closure of the interfaces of the superclass.
6409 // The other entries are uninitialized. We will fill in the remaining entries in this function. The
6410 // iftable must be large enough to hold all interfaces without changing its size.
6411 static size_t FillIfTable(ObjPtr<mirror::IfTable> iftable,
6412 size_t super_ifcount,
6413 std::vector<mirror::Class*> to_process)
6414 REQUIRES(Roles::uninterruptible_)
6415 REQUIRES_SHARED(Locks::mutator_lock_) {
6416 // This is the set of all class's already in the iftable. Used to make checking if a class has
6417 // already been added quicker.
6418 std::unordered_set<ObjPtr<mirror::Class>, HashObjPtr> classes_in_iftable;
6419 // The first super_ifcount elements are from the superclass. We note that they are already added.
6420 for (size_t i = 0; i < super_ifcount; i++) {
6421 ObjPtr<mirror::Class> iface = iftable->GetInterface(i);
6422 DCHECK(NotSubinterfaceOfAny(classes_in_iftable, iface)) << "Bad ordering.";
6423 classes_in_iftable.insert(iface);
6425 size_t filled_ifcount = super_ifcount;
6426 for (ObjPtr<mirror::Class> interface : to_process) {
6427 // Let us call the first filled_ifcount elements of iftable the current-iface-list.
6428 // At this point in the loop current-iface-list has the invariant that:
6429 // for every pair of interfaces I,J within it:
6430 // if index_of(I) < index_of(J) then I is not a subtype of J
6432 // If we have already seen this element then all of its super-interfaces must already be in the
6433 // current-iface-list so we can skip adding it.
6434 if (!ContainsElement(classes_in_iftable, interface)) {
6435 // We haven't seen this interface so add all of its super-interfaces onto the
6436 // current-iface-list, skipping those already on it.
6437 int32_t ifcount = interface->GetIfTableCount();
6438 for (int32_t j = 0; j < ifcount; j++) {
6439 ObjPtr<mirror::Class> super_interface = interface->GetIfTable()->GetInterface(j);
6440 if (!ContainsElement(classes_in_iftable, super_interface)) {
6441 DCHECK(NotSubinterfaceOfAny(classes_in_iftable, super_interface)) << "Bad ordering.";
6442 classes_in_iftable.insert(super_interface);
6443 iftable->SetInterface(filled_ifcount, super_interface);
6447 DCHECK(NotSubinterfaceOfAny(classes_in_iftable, interface)) << "Bad ordering";
6448 // Place this interface onto the current-iface-list after all of its super-interfaces.
6449 classes_in_iftable.insert(interface);
6450 iftable->SetInterface(filled_ifcount, interface);
6452 } else if (kIsDebugBuild) {
6453 // Check all super-interfaces are already in the list.
6454 int32_t ifcount = interface->GetIfTableCount();
6455 for (int32_t j = 0; j < ifcount; j++) {
6456 ObjPtr<mirror::Class> super_interface = interface->GetIfTable()->GetInterface(j);
6457 DCHECK(ContainsElement(classes_in_iftable, super_interface))
6458 << "Iftable does not contain " << mirror::Class::PrettyClass(super_interface)
6459 << ", a superinterface of " << interface->PrettyClass();
6463 if (kIsDebugBuild) {
6464 // Check that the iftable is ordered correctly.
6465 for (size_t i = 0; i < filled_ifcount; i++) {
6466 ObjPtr<mirror::Class> if_a = iftable->GetInterface(i);
6467 for (size_t j = i + 1; j < filled_ifcount; j++) {
6468 ObjPtr<mirror::Class> if_b = iftable->GetInterface(j);
6470 CHECK(!if_b->IsAssignableFrom(if_a))
6471 << "Bad interface order: " << mirror::Class::PrettyClass(if_a) << " (index " << i
6473 << if_b->PrettyClass() << " (index " << j << ") and so should be after it in the "
6474 << "interface list.";
6478 return filled_ifcount;
6481 bool ClassLinker::SetupInterfaceLookupTable(Thread* self, Handle<mirror::Class> klass,
6482 Handle<mirror::ObjectArray<mirror::Class>> interfaces) {
6483 StackHandleScope<1> hs(self);
6484 const bool has_superclass = klass->HasSuperClass();
6485 const size_t super_ifcount = has_superclass ? klass->GetSuperClass()->GetIfTableCount() : 0U;
6486 const bool have_interfaces = interfaces.Get() != nullptr;
6487 const size_t num_interfaces =
6488 have_interfaces ? interfaces->GetLength() : klass->NumDirectInterfaces();
6489 if (num_interfaces == 0) {
6490 if (super_ifcount == 0) {
6491 if (LIKELY(has_superclass)) {
6492 klass->SetIfTable(klass->GetSuperClass()->GetIfTable());
6494 // Class implements no interfaces.
6495 DCHECK_EQ(klass->GetIfTableCount(), 0);
6498 // Class implements same interfaces as parent, are any of these not marker interfaces?
6499 bool has_non_marker_interface = false;
6500 ObjPtr<mirror::IfTable> super_iftable = klass->GetSuperClass()->GetIfTable();
6501 for (size_t i = 0; i < super_ifcount; ++i) {
6502 if (super_iftable->GetMethodArrayCount(i) > 0) {
6503 has_non_marker_interface = true;
6507 // Class just inherits marker interfaces from parent so recycle parent's iftable.
6508 if (!has_non_marker_interface) {
6509 klass->SetIfTable(super_iftable);
6513 size_t ifcount = super_ifcount + num_interfaces;
6514 // Check that every class being implemented is an interface.
6515 for (size_t i = 0; i < num_interfaces; i++) {
6516 ObjPtr<mirror::Class> interface = have_interfaces
6517 ? interfaces->GetWithoutChecks(i)
6518 : mirror::Class::GetDirectInterface(self, klass.Get(), i);
6519 DCHECK(interface != nullptr);
6520 if (UNLIKELY(!interface->IsInterface())) {
6522 ThrowIncompatibleClassChangeError(klass.Get(),
6523 "Class %s implements non-interface class %s",
6524 klass->PrettyDescriptor().c_str(),
6525 PrettyDescriptor(interface->GetDescriptor(&temp)).c_str());
6528 ifcount += interface->GetIfTableCount();
6530 // Create the interface function table.
6531 MutableHandle<mirror::IfTable> iftable(hs.NewHandle(AllocIfTable(self, ifcount)));
6532 if (UNLIKELY(iftable.Get() == nullptr)) {
6533 self->AssertPendingOOMException();
6536 // Fill in table with superclass's iftable.
6537 if (super_ifcount != 0) {
6538 ObjPtr<mirror::IfTable> super_iftable = klass->GetSuperClass()->GetIfTable();
6539 for (size_t i = 0; i < super_ifcount; i++) {
6540 ObjPtr<mirror::Class> super_interface = super_iftable->GetInterface(i);
6541 iftable->SetInterface(i, super_interface);
6545 // Note that AllowThreadSuspension is to thread suspension as pthread_testcancel is to pthread
6546 // cancellation. That is it will suspend if one has a pending suspend request but otherwise
6547 // doesn't really do anything.
6548 self->AllowThreadSuspension();
6552 ScopedAssertNoThreadSuspension nts("Copying mirror::Class*'s for FillIfTable");
6553 std::vector<mirror::Class*> to_add;
6554 for (size_t i = 0; i < num_interfaces; i++) {
6555 ObjPtr<mirror::Class> interface = have_interfaces ? interfaces->Get(i) :
6556 mirror::Class::GetDirectInterface(self, klass.Get(), i);
6557 to_add.push_back(interface.Ptr());
6560 new_ifcount = FillIfTable(iftable.Get(), super_ifcount, std::move(to_add));
6563 self->AllowThreadSuspension();
6565 // Shrink iftable in case duplicates were found
6566 if (new_ifcount < ifcount) {
6567 DCHECK_NE(num_interfaces, 0U);
6568 iftable.Assign(down_cast<mirror::IfTable*>(
6569 iftable->CopyOf(self, new_ifcount * mirror::IfTable::kMax)));
6570 if (UNLIKELY(iftable.Get() == nullptr)) {
6571 self->AssertPendingOOMException();
6574 ifcount = new_ifcount;
6576 DCHECK_EQ(new_ifcount, ifcount);
6578 klass->SetIfTable(iftable.Get());
6582 // Finds the method with a name/signature that matches cmp in the given lists of methods. The list
6583 // of methods must be unique.
6584 static ArtMethod* FindSameNameAndSignature(MethodNameAndSignatureComparator& cmp ATTRIBUTE_UNUSED) {
6588 template <typename ... Types>
6589 static ArtMethod* FindSameNameAndSignature(MethodNameAndSignatureComparator& cmp,
6590 const ScopedArenaVector<ArtMethod*>& list,
6591 const Types& ... rest)
6592 REQUIRES_SHARED(Locks::mutator_lock_) {
6593 for (ArtMethod* method : list) {
6594 if (cmp.HasSameNameAndSignature(method)) {
6598 return FindSameNameAndSignature(cmp, rest...);
6601 // Check that all vtable entries are present in this class's virtuals or are the same as a
6602 // superclasses vtable entry.
6603 static void CheckClassOwnsVTableEntries(Thread* self,
6604 Handle<mirror::Class> klass,
6605 PointerSize pointer_size)
6606 REQUIRES_SHARED(Locks::mutator_lock_) {
6607 StackHandleScope<2> hs(self);
6608 Handle<mirror::PointerArray> check_vtable(hs.NewHandle(klass->GetVTableDuringLinking()));
6609 ObjPtr<mirror::Class> super_temp = (klass->HasSuperClass()) ? klass->GetSuperClass() : nullptr;
6610 Handle<mirror::Class> superclass(hs.NewHandle(super_temp));
6611 int32_t super_vtable_length = (superclass.Get() != nullptr) ? superclass->GetVTableLength() : 0;
6612 for (int32_t i = 0; i < check_vtable->GetLength(); ++i) {
6613 ArtMethod* m = check_vtable->GetElementPtrSize<ArtMethod*>(i, pointer_size);
6614 CHECK(m != nullptr);
6616 CHECK_EQ(m->GetMethodIndexDuringLinking(), i)
6617 << m->PrettyMethod()
6618 << " has an unexpected method index for its spot in the vtable for class"
6619 << klass->PrettyClass();
6620 ArraySlice<ArtMethod> virtuals = klass->GetVirtualMethodsSliceUnchecked(pointer_size);
6621 auto is_same_method = [m] (const ArtMethod& meth) {
6624 CHECK((super_vtable_length > i && superclass->GetVTableEntry(i, pointer_size) == m) ||
6625 std::find_if(virtuals.begin(), virtuals.end(), is_same_method) != virtuals.end())
6626 << m->PrettyMethod() << " does not seem to be owned by current class "
6627 << klass->PrettyClass() << " or any of its superclasses!";
6631 // Check to make sure the vtable does not have duplicates. Duplicates could cause problems when a
6632 // method is overridden in a subclass.
6633 static void CheckVTableHasNoDuplicates(Thread* self,
6634 Handle<mirror::Class> klass,
6635 PointerSize pointer_size)
6636 REQUIRES_SHARED(Locks::mutator_lock_) {
6637 StackHandleScope<1> hs(self);
6638 Handle<mirror::PointerArray> vtable(hs.NewHandle(klass->GetVTableDuringLinking()));
6639 int32_t num_entries = vtable->GetLength();
6640 for (int32_t i = 0; i < num_entries; i++) {
6641 ArtMethod* vtable_entry = vtable->GetElementPtrSize<ArtMethod*>(i, pointer_size);
6642 // Don't bother if we cannot 'see' the vtable entry (i.e. it is a package-private member maybe).
6643 if (!klass->CanAccessMember(vtable_entry->GetDeclaringClass(),
6644 vtable_entry->GetAccessFlags())) {
6647 MethodNameAndSignatureComparator name_comparator(
6648 vtable_entry->GetInterfaceMethodIfProxy(pointer_size));
6649 for (int32_t j = i + 1; j < num_entries; j++) {
6650 ArtMethod* other_entry = vtable->GetElementPtrSize<ArtMethod*>(j, pointer_size);
6651 if (!klass->CanAccessMember(other_entry->GetDeclaringClass(),
6652 other_entry->GetAccessFlags())) {
6655 CHECK(vtable_entry != other_entry &&
6656 !name_comparator.HasSameNameAndSignature(
6657 other_entry->GetInterfaceMethodIfProxy(pointer_size)))
6658 << "vtable entries " << i << " and " << j << " are identical for "
6659 << klass->PrettyClass() << " in method " << vtable_entry->PrettyMethod() << " (0x"
6660 << std::hex << reinterpret_cast<uintptr_t>(vtable_entry) << ") and "
6661 << other_entry->PrettyMethod() << " (0x" << std::hex
6662 << reinterpret_cast<uintptr_t>(other_entry) << ")";
6667 static void SanityCheckVTable(Thread* self, Handle<mirror::Class> klass, PointerSize pointer_size)
6668 REQUIRES_SHARED(Locks::mutator_lock_) {
6669 CheckClassOwnsVTableEntries(self, klass, pointer_size);
6670 CheckVTableHasNoDuplicates(self, klass, pointer_size);
6673 void ClassLinker::FillImtFromSuperClass(Handle<mirror::Class> klass,
6674 ArtMethod* unimplemented_method,
6675 ArtMethod* imt_conflict_method,
6678 DCHECK(klass->HasSuperClass());
6679 ObjPtr<mirror::Class> super_class = klass->GetSuperClass();
6680 if (super_class->ShouldHaveImt()) {
6681 ImTable* super_imt = super_class->GetImt(image_pointer_size_);
6682 for (size_t i = 0; i < ImTable::kSize; ++i) {
6683 imt[i] = super_imt->Get(i, image_pointer_size_);
6686 // No imt in the super class, need to reconstruct from the iftable.
6687 ObjPtr<mirror::IfTable> if_table = super_class->GetIfTable();
6688 if (if_table->Count() != 0) {
6689 // Ignore copied methods since we will handle these in LinkInterfaceMethods.
6690 FillIMTFromIfTable(if_table,
6691 unimplemented_method,
6692 imt_conflict_method,
6694 /*create_conflict_table*/false,
6695 /*ignore_copied_methods*/true,
6696 /*out*/new_conflict,
6702 class ClassLinker::LinkInterfaceMethodsHelper {
6704 LinkInterfaceMethodsHelper(ClassLinker* class_linker,
6705 Handle<mirror::Class> klass,
6708 : class_linker_(class_linker),
6710 method_alignment_(ArtMethod::Alignment(class_linker->GetImagePointerSize())),
6711 method_size_(ArtMethod::Size(class_linker->GetImagePointerSize())),
6713 stack_(runtime->GetLinearAlloc()->GetArenaPool()),
6714 allocator_(&stack_),
6715 default_conflict_methods_(allocator_.Adapter()),
6716 overriding_default_conflict_methods_(allocator_.Adapter()),
6717 miranda_methods_(allocator_.Adapter()),
6718 default_methods_(allocator_.Adapter()),
6719 overriding_default_methods_(allocator_.Adapter()),
6720 move_table_(allocator_.Adapter()) {
6723 ArtMethod* FindMethod(ArtMethod* interface_method,
6724 MethodNameAndSignatureComparator& interface_name_comparator,
6725 ArtMethod* vtable_impl)
6726 REQUIRES_SHARED(Locks::mutator_lock_);
6728 ArtMethod* GetOrCreateMirandaMethod(ArtMethod* interface_method,
6729 MethodNameAndSignatureComparator& interface_name_comparator)
6730 REQUIRES_SHARED(Locks::mutator_lock_);
6732 bool HasNewVirtuals() const {
6733 return !(miranda_methods_.empty() &&
6734 default_methods_.empty() &&
6735 overriding_default_methods_.empty() &&
6736 overriding_default_conflict_methods_.empty() &&
6737 default_conflict_methods_.empty());
6740 void ReallocMethods() REQUIRES_SHARED(Locks::mutator_lock_);
6742 ObjPtr<mirror::PointerArray> UpdateVtable(
6743 const std::unordered_map<size_t, ClassLinker::MethodTranslation>& default_translations,
6744 ObjPtr<mirror::PointerArray> old_vtable) REQUIRES_SHARED(Locks::mutator_lock_);
6746 void UpdateIfTable(Handle<mirror::IfTable> iftable) REQUIRES_SHARED(Locks::mutator_lock_);
6748 void UpdateIMT(ArtMethod** out_imt);
6750 void CheckNoStaleMethodsInDexCache() REQUIRES_SHARED(Locks::mutator_lock_) {
6751 if (kIsDebugBuild) {
6752 PointerSize pointer_size = class_linker_->GetImagePointerSize();
6753 // Check that there are no stale methods are in the dex cache array.
6754 auto* resolved_methods = klass_->GetDexCache()->GetResolvedMethods();
6755 for (size_t i = 0, count = klass_->GetDexCache()->NumResolvedMethods(); i < count; ++i) {
6756 auto* m = mirror::DexCache::GetElementPtrSize(resolved_methods, i, pointer_size);
6757 CHECK(move_table_.find(m) == move_table_.end() ||
6758 // The original versions of copied methods will still be present so allow those too.
6759 // Note that if the first check passes this might fail to GetDeclaringClass().
6760 std::find_if(m->GetDeclaringClass()->GetMethods(pointer_size).begin(),
6761 m->GetDeclaringClass()->GetMethods(pointer_size).end(),
6762 [m] (ArtMethod& meth) {
6764 }) != m->GetDeclaringClass()->GetMethods(pointer_size).end())
6765 << "Obsolete method " << m->PrettyMethod() << " is in dex cache!";
6770 void ClobberOldMethods(LengthPrefixedArray<ArtMethod>* old_methods,
6771 LengthPrefixedArray<ArtMethod>* methods) {
6772 if (kIsDebugBuild) {
6773 CHECK(methods != nullptr);
6774 // Put some random garbage in old methods to help find stale pointers.
6775 if (methods != old_methods && old_methods != nullptr) {
6776 // Need to make sure the GC is not running since it could be scanning the methods we are
6777 // about to overwrite.
6778 ScopedThreadStateChange tsc(self_, kSuspended);
6779 gc::ScopedGCCriticalSection gcs(self_,
6780 gc::kGcCauseClassLinker,
6781 gc::kCollectorTypeClassLinker);
6782 const size_t old_size = LengthPrefixedArray<ArtMethod>::ComputeSize(old_methods->size(),
6785 memset(old_methods, 0xFEu, old_size);
6791 size_t NumberOfNewVirtuals() const {
6792 return miranda_methods_.size() +
6793 default_methods_.size() +
6794 overriding_default_conflict_methods_.size() +
6795 overriding_default_methods_.size() +
6796 default_conflict_methods_.size();
6799 bool FillTables() REQUIRES_SHARED(Locks::mutator_lock_) {
6800 return !klass_->IsInterface();
6803 void LogNewVirtuals() const REQUIRES_SHARED(Locks::mutator_lock_) {
6804 DCHECK(!klass_->IsInterface() || (default_methods_.empty() && miranda_methods_.empty()))
6805 << "Interfaces should only have default-conflict methods appended to them.";
6806 VLOG(class_linker) << mirror::Class::PrettyClass(klass_.Get()) << ": miranda_methods="
6807 << miranda_methods_.size()
6808 << " default_methods=" << default_methods_.size()
6809 << " overriding_default_methods=" << overriding_default_methods_.size()
6810 << " default_conflict_methods=" << default_conflict_methods_.size()
6811 << " overriding_default_conflict_methods="
6812 << overriding_default_conflict_methods_.size();
6815 ClassLinker* class_linker_;
6816 Handle<mirror::Class> klass_;
6817 size_t method_alignment_;
6818 size_t method_size_;
6819 Thread* const self_;
6821 // These are allocated on the heap to begin, we then transfer to linear alloc when we re-create
6822 // the virtual methods array.
6823 // Need to use low 4GB arenas for compiler or else the pointers wont fit in 32 bit method array
6824 // during cross compilation.
6825 // Use the linear alloc pool since this one is in the low 4gb for the compiler.
6827 ScopedArenaAllocator allocator_;
6829 ScopedArenaVector<ArtMethod*> default_conflict_methods_;
6830 ScopedArenaVector<ArtMethod*> overriding_default_conflict_methods_;
6831 ScopedArenaVector<ArtMethod*> miranda_methods_;
6832 ScopedArenaVector<ArtMethod*> default_methods_;
6833 ScopedArenaVector<ArtMethod*> overriding_default_methods_;
6835 ScopedArenaUnorderedMap<ArtMethod*, ArtMethod*> move_table_;
6838 ArtMethod* ClassLinker::LinkInterfaceMethodsHelper::FindMethod(
6839 ArtMethod* interface_method,
6840 MethodNameAndSignatureComparator& interface_name_comparator,
6841 ArtMethod* vtable_impl) {
6842 ArtMethod* current_method = nullptr;
6843 switch (class_linker_->FindDefaultMethodImplementation(self_,
6846 /*out*/¤t_method)) {
6847 case DefaultMethodSearchResult::kDefaultConflict: {
6848 // Default method conflict.
6849 DCHECK(current_method == nullptr);
6850 ArtMethod* default_conflict_method = nullptr;
6851 if (vtable_impl != nullptr && vtable_impl->IsDefaultConflicting()) {
6852 // We can reuse the method from the superclass, don't bother adding it to virtuals.
6853 default_conflict_method = vtable_impl;
6855 // See if we already have a conflict method for this method.
6856 ArtMethod* preexisting_conflict = FindSameNameAndSignature(
6857 interface_name_comparator,
6858 default_conflict_methods_,
6859 overriding_default_conflict_methods_);
6860 if (LIKELY(preexisting_conflict != nullptr)) {
6861 // We already have another conflict we can reuse.
6862 default_conflict_method = preexisting_conflict;
6864 // Note that we do this even if we are an interface since we need to create this and
6865 // cannot reuse another classes.
6866 // Create a new conflict method for this to use.
6867 default_conflict_method = reinterpret_cast<ArtMethod*>(allocator_.Alloc(method_size_));
6868 new(default_conflict_method) ArtMethod(interface_method,
6869 class_linker_->GetImagePointerSize());
6870 if (vtable_impl == nullptr) {
6871 // Save the conflict method. We need to add it to the vtable.
6872 default_conflict_methods_.push_back(default_conflict_method);
6874 // Save the conflict method but it is already in the vtable.
6875 overriding_default_conflict_methods_.push_back(default_conflict_method);
6879 current_method = default_conflict_method;
6881 } // case kDefaultConflict
6882 case DefaultMethodSearchResult::kDefaultFound: {
6883 DCHECK(current_method != nullptr);
6884 // Found a default method.
6885 if (vtable_impl != nullptr &&
6886 current_method->GetDeclaringClass() == vtable_impl->GetDeclaringClass()) {
6887 // We found a default method but it was the same one we already have from our
6888 // superclass. Don't bother adding it to our vtable again.
6889 current_method = vtable_impl;
6890 } else if (LIKELY(FillTables())) {
6891 // Interfaces don't need to copy default methods since they don't have vtables.
6892 // Only record this default method if it is new to save space.
6893 // TODO It might be worthwhile to copy default methods on interfaces anyway since it
6894 // would make lookup for interface super much faster. (We would only need to scan
6895 // the iftable to find if there is a NSME or AME.)
6896 ArtMethod* old = FindSameNameAndSignature(interface_name_comparator,
6898 overriding_default_methods_);
6899 if (old == nullptr) {
6900 // We found a default method implementation and there were no conflicts.
6901 if (vtable_impl == nullptr) {
6902 // Save the default method. We need to add it to the vtable.
6903 default_methods_.push_back(current_method);
6905 // Save the default method but it is already in the vtable.
6906 overriding_default_methods_.push_back(current_method);
6909 CHECK(old == current_method) << "Multiple default implementations selected!";
6913 } // case kDefaultFound
6914 case DefaultMethodSearchResult::kAbstractFound: {
6915 DCHECK(current_method == nullptr);
6916 // Abstract method masks all defaults.
6917 if (vtable_impl != nullptr &&
6918 vtable_impl->IsAbstract() &&
6919 !vtable_impl->IsDefaultConflicting()) {
6920 // We need to make this an abstract method but the version in the vtable already is so
6921 // don't do anything.
6922 current_method = vtable_impl;
6925 } // case kAbstractFound
6927 return current_method;
6930 ArtMethod* ClassLinker::LinkInterfaceMethodsHelper::GetOrCreateMirandaMethod(
6931 ArtMethod* interface_method,
6932 MethodNameAndSignatureComparator& interface_name_comparator) {
6933 // Find out if there is already a miranda method we can use.
6934 ArtMethod* miranda_method = FindSameNameAndSignature(interface_name_comparator,
6936 if (miranda_method == nullptr) {
6937 DCHECK(interface_method->IsAbstract()) << interface_method->PrettyMethod();
6938 miranda_method = reinterpret_cast<ArtMethod*>(allocator_.Alloc(method_size_));
6939 CHECK(miranda_method != nullptr);
6940 // Point the interface table at a phantom slot.
6941 new(miranda_method) ArtMethod(interface_method, class_linker_->GetImagePointerSize());
6942 miranda_methods_.push_back(miranda_method);
6944 return miranda_method;
6947 void ClassLinker::LinkInterfaceMethodsHelper::ReallocMethods() {
6950 const size_t old_method_count = klass_->NumMethods();
6951 const size_t new_method_count = old_method_count + NumberOfNewVirtuals();
6952 DCHECK_NE(old_method_count, new_method_count);
6954 // Attempt to realloc to save RAM if possible.
6955 LengthPrefixedArray<ArtMethod>* old_methods = klass_->GetMethodsPtr();
6956 // The Realloced virtual methods aren't visible from the class roots, so there is no issue
6957 // where GCs could attempt to mark stale pointers due to memcpy. And since we overwrite the
6958 // realloced memory with out->CopyFrom, we are guaranteed to have objects in the to space since
6959 // CopyFrom has internal read barriers.
6961 // TODO We should maybe move some of this into mirror::Class or at least into another method.
6962 const size_t old_size = LengthPrefixedArray<ArtMethod>::ComputeSize(old_method_count,
6965 const size_t new_size = LengthPrefixedArray<ArtMethod>::ComputeSize(new_method_count,
6968 const size_t old_methods_ptr_size = (old_methods != nullptr) ? old_size : 0;
6969 auto* methods = reinterpret_cast<LengthPrefixedArray<ArtMethod>*>(
6970 Runtime::Current()->GetLinearAlloc()->Realloc(
6971 self_, old_methods, old_methods_ptr_size, new_size));
6972 CHECK(methods != nullptr); // Native allocation failure aborts.
6974 PointerSize pointer_size = class_linker_->GetImagePointerSize();
6975 if (methods != old_methods) {
6976 // Maps from heap allocated miranda method to linear alloc miranda method.
6977 StrideIterator<ArtMethod> out = methods->begin(method_size_, method_alignment_);
6978 // Copy over the old methods.
6979 for (auto& m : klass_->GetMethods(pointer_size)) {
6980 move_table_.emplace(&m, &*out);
6981 // The CopyFrom is only necessary to not miss read barriers since Realloc won't do read
6982 // barriers when it copies.
6983 out->CopyFrom(&m, pointer_size);
6987 StrideIterator<ArtMethod> out(methods->begin(method_size_, method_alignment_) + old_method_count);
6988 // Copy over miranda methods before copying vtable since CopyOf may cause thread suspension and
6989 // we want the roots of the miranda methods to get visited.
6990 for (size_t i = 0; i < miranda_methods_.size(); ++i) {
6991 ArtMethod* mir_method = miranda_methods_[i];
6992 ArtMethod& new_method = *out;
6993 new_method.CopyFrom(mir_method, pointer_size);
6994 new_method.SetAccessFlags(new_method.GetAccessFlags() | kAccMiranda | kAccCopied);
6995 DCHECK_NE(new_method.GetAccessFlags() & kAccAbstract, 0u)
6996 << "Miranda method should be abstract!";
6997 move_table_.emplace(mir_method, &new_method);
6998 // Update the entry in the method array, as the array will be used for future lookups,
6999 // where thread suspension is allowed.
7000 // As such, the array should not contain locally allocated ArtMethod, otherwise the GC
7001 // would not see them.
7002 miranda_methods_[i] = &new_method;
7005 // We need to copy the default methods into our own method table since the runtime requires that
7006 // every method on a class's vtable be in that respective class's virtual method table.
7007 // NOTE This means that two classes might have the same implementation of a method from the same
7008 // interface but will have different ArtMethod*s for them. This also means we cannot compare a
7009 // default method found on a class with one found on the declaring interface directly and must
7010 // look at the declaring class to determine if they are the same.
7011 for (ScopedArenaVector<ArtMethod*>* methods_vec : {&default_methods_,
7012 &overriding_default_methods_}) {
7013 for (size_t i = 0; i < methods_vec->size(); ++i) {
7014 ArtMethod* def_method = (*methods_vec)[i];
7015 ArtMethod& new_method = *out;
7016 new_method.CopyFrom(def_method, pointer_size);
7017 // Clear the kAccSkipAccessChecks flag if it is present. Since this class hasn't been
7018 // verified yet it shouldn't have methods that are skipping access checks.
7019 // TODO This is rather arbitrary. We should maybe support classes where only some of its
7020 // methods are skip_access_checks.
7021 constexpr uint32_t kSetFlags = kAccDefault | kAccCopied;
7022 constexpr uint32_t kMaskFlags = ~kAccSkipAccessChecks;
7023 new_method.SetAccessFlags((new_method.GetAccessFlags() | kSetFlags) & kMaskFlags);
7024 move_table_.emplace(def_method, &new_method);
7025 // Update the entry in the method array, as the array will be used for future lookups,
7026 // where thread suspension is allowed.
7027 // As such, the array should not contain locally allocated ArtMethod, otherwise the GC
7028 // would not see them.
7029 (*methods_vec)[i] = &new_method;
7033 for (ScopedArenaVector<ArtMethod*>* methods_vec : {&default_conflict_methods_,
7034 &overriding_default_conflict_methods_}) {
7035 for (size_t i = 0; i < methods_vec->size(); ++i) {
7036 ArtMethod* conf_method = (*methods_vec)[i];
7037 ArtMethod& new_method = *out;
7038 new_method.CopyFrom(conf_method, pointer_size);
7039 // This is a type of default method (there are default method impls, just a conflict) so
7040 // mark this as a default, non-abstract method, since thats what it is. Also clear the
7041 // kAccSkipAccessChecks bit since this class hasn't been verified yet it shouldn't have
7042 // methods that are skipping access checks.
7043 constexpr uint32_t kSetFlags = kAccDefault | kAccDefaultConflict | kAccCopied;
7044 constexpr uint32_t kMaskFlags = ~(kAccAbstract | kAccSkipAccessChecks);
7045 new_method.SetAccessFlags((new_method.GetAccessFlags() | kSetFlags) & kMaskFlags);
7046 DCHECK(new_method.IsDefaultConflicting());
7047 // The actual method might or might not be marked abstract since we just copied it from a
7048 // (possibly default) interface method. We need to set it entry point to be the bridge so
7049 // that the compiler will not invoke the implementation of whatever method we copied from.
7050 EnsureThrowsInvocationError(class_linker_, &new_method);
7051 move_table_.emplace(conf_method, &new_method);
7052 // Update the entry in the method array, as the array will be used for future lookups,
7053 // where thread suspension is allowed.
7054 // As such, the array should not contain locally allocated ArtMethod, otherwise the GC
7055 // would not see them.
7056 (*methods_vec)[i] = &new_method;
7060 methods->SetSize(new_method_count);
7061 class_linker_->UpdateClassMethods(klass_.Get(), methods);
7064 ObjPtr<mirror::PointerArray> ClassLinker::LinkInterfaceMethodsHelper::UpdateVtable(
7065 const std::unordered_map<size_t, ClassLinker::MethodTranslation>& default_translations,
7066 ObjPtr<mirror::PointerArray> old_vtable) {
7067 // Update the vtable to the new method structures. We can skip this for interfaces since they
7068 // do not have vtables.
7069 const size_t old_vtable_count = old_vtable->GetLength();
7070 const size_t new_vtable_count = old_vtable_count +
7071 miranda_methods_.size() +
7072 default_methods_.size() +
7073 default_conflict_methods_.size();
7075 ObjPtr<mirror::PointerArray> vtable =
7076 down_cast<mirror::PointerArray*>(old_vtable->CopyOf(self_, new_vtable_count));
7077 if (UNLIKELY(vtable == nullptr)) {
7078 self_->AssertPendingOOMException();
7082 size_t vtable_pos = old_vtable_count;
7083 PointerSize pointer_size = class_linker_->GetImagePointerSize();
7084 // Update all the newly copied method's indexes so they denote their placement in the vtable.
7085 for (const ScopedArenaVector<ArtMethod*>& methods_vec : {default_methods_,
7086 default_conflict_methods_,
7087 miranda_methods_}) {
7088 // These are the functions that are not already in the vtable!
7089 for (ArtMethod* new_vtable_method : methods_vec) {
7090 // Leave the declaring class alone the method's dex_code_item_offset_ and dex_method_index_
7091 // fields are references into the dex file the method was defined in. Since the ArtMethod
7092 // does not store that information it uses declaring_class_->dex_cache_.
7093 new_vtable_method->SetMethodIndex(0xFFFF & vtable_pos);
7094 vtable->SetElementPtrSize(vtable_pos, new_vtable_method, pointer_size);
7098 DCHECK_EQ(vtable_pos, new_vtable_count);
7100 // Update old vtable methods. We use the default_translations map to figure out what each
7101 // vtable entry should be updated to, if they need to be at all.
7102 for (size_t i = 0; i < old_vtable_count; ++i) {
7103 ArtMethod* translated_method = vtable->GetElementPtrSize<ArtMethod*>(i, pointer_size);
7104 // Try and find what we need to change this method to.
7105 auto translation_it = default_translations.find(i);
7106 if (translation_it != default_translations.end()) {
7107 if (translation_it->second.IsInConflict()) {
7108 // Find which conflict method we are to use for this method.
7109 MethodNameAndSignatureComparator old_method_comparator(
7110 translated_method->GetInterfaceMethodIfProxy(pointer_size));
7111 // We only need to look through overriding_default_conflict_methods since this is an
7112 // overridden method we are fixing up here.
7113 ArtMethod* new_conflict_method = FindSameNameAndSignature(
7114 old_method_comparator, overriding_default_conflict_methods_);
7115 CHECK(new_conflict_method != nullptr) << "Expected a conflict method!";
7116 translated_method = new_conflict_method;
7117 } else if (translation_it->second.IsAbstract()) {
7118 // Find which miranda method we are to use for this method.
7119 MethodNameAndSignatureComparator old_method_comparator(
7120 translated_method->GetInterfaceMethodIfProxy(pointer_size));
7121 ArtMethod* miranda_method = FindSameNameAndSignature(old_method_comparator,
7123 DCHECK(miranda_method != nullptr);
7124 translated_method = miranda_method;
7126 // Normal default method (changed from an older default or abstract interface method).
7127 DCHECK(translation_it->second.IsTranslation());
7128 translated_method = translation_it->second.GetTranslation();
7129 auto it = move_table_.find(translated_method);
7130 DCHECK(it != move_table_.end());
7131 translated_method = it->second;
7134 auto it = move_table_.find(translated_method);
7135 translated_method = (it != move_table_.end()) ? it->second : nullptr;
7138 if (translated_method != nullptr) {
7139 // Make sure the new_methods index is set.
7140 if (translated_method->GetMethodIndexDuringLinking() != i) {
7141 if (kIsDebugBuild) {
7142 auto* methods = klass_->GetMethodsPtr();
7143 CHECK_LE(reinterpret_cast<uintptr_t>(&*methods->begin(method_size_, method_alignment_)),
7144 reinterpret_cast<uintptr_t>(translated_method));
7145 CHECK_LT(reinterpret_cast<uintptr_t>(translated_method),
7146 reinterpret_cast<uintptr_t>(&*methods->end(method_size_, method_alignment_)));
7148 translated_method->SetMethodIndex(0xFFFF & i);
7150 vtable->SetElementPtrSize(i, translated_method, pointer_size);
7153 klass_->SetVTable(vtable.Ptr());
7157 void ClassLinker::LinkInterfaceMethodsHelper::UpdateIfTable(Handle<mirror::IfTable> iftable) {
7158 PointerSize pointer_size = class_linker_->GetImagePointerSize();
7159 const size_t ifcount = klass_->GetIfTableCount();
7160 // Go fix up all the stale iftable pointers.
7161 for (size_t i = 0; i < ifcount; ++i) {
7162 for (size_t j = 0, count = iftable->GetMethodArrayCount(i); j < count; ++j) {
7163 auto* method_array = iftable->GetMethodArray(i);
7164 auto* m = method_array->GetElementPtrSize<ArtMethod*>(j, pointer_size);
7165 DCHECK(m != nullptr) << klass_->PrettyClass();
7166 auto it = move_table_.find(m);
7167 if (it != move_table_.end()) {
7168 auto* new_m = it->second;
7169 DCHECK(new_m != nullptr) << klass_->PrettyClass();
7170 method_array->SetElementPtrSize(j, new_m, pointer_size);
7176 void ClassLinker::LinkInterfaceMethodsHelper::UpdateIMT(ArtMethod** out_imt) {
7178 for (size_t i = 0; i < ImTable::kSize; ++i) {
7179 auto it = move_table_.find(out_imt[i]);
7180 if (it != move_table_.end()) {
7181 out_imt[i] = it->second;
7186 // TODO This method needs to be split up into several smaller methods.
7187 bool ClassLinker::LinkInterfaceMethods(
7189 Handle<mirror::Class> klass,
7190 const std::unordered_map<size_t, ClassLinker::MethodTranslation>& default_translations,
7191 bool* out_new_conflict,
7192 ArtMethod** out_imt) {
7193 StackHandleScope<3> hs(self);
7194 Runtime* const runtime = Runtime::Current();
7196 const bool is_interface = klass->IsInterface();
7197 const bool has_superclass = klass->HasSuperClass();
7198 const bool fill_tables = !is_interface;
7199 const size_t super_ifcount = has_superclass ? klass->GetSuperClass()->GetIfTableCount() : 0U;
7200 const size_t ifcount = klass->GetIfTableCount();
7202 Handle<mirror::IfTable> iftable(hs.NewHandle(klass->GetIfTable()));
7204 MutableHandle<mirror::PointerArray> vtable(hs.NewHandle(klass->GetVTableDuringLinking()));
7205 ArtMethod* const unimplemented_method = runtime->GetImtUnimplementedMethod();
7206 ArtMethod* const imt_conflict_method = runtime->GetImtConflictMethod();
7207 // Copy the IMT from the super class if possible.
7208 const bool extend_super_iftable = has_superclass;
7209 if (has_superclass && fill_tables) {
7210 FillImtFromSuperClass(klass,
7211 unimplemented_method,
7212 imt_conflict_method,
7216 // Allocate method arrays before since we don't want miss visiting miranda method roots due to
7217 // thread suspension.
7219 if (!AllocateIfTableMethodArrays(self, klass, iftable)) {
7224 LinkInterfaceMethodsHelper helper(this, klass, self, runtime);
7226 auto* old_cause = self->StartAssertNoThreadSuspension(
7227 "Copying ArtMethods for LinkInterfaceMethods");
7228 // Going in reverse to ensure that we will hit abstract methods that override defaults before the
7229 // defaults. This means we don't need to do any trickery when creating the Miranda methods, since
7230 // they will already be null. This has the additional benefit that the declarer of a miranda
7231 // method will actually declare an abstract method.
7232 for (size_t i = ifcount; i != 0; ) {
7236 DCHECK_LT(i, ifcount);
7238 size_t num_methods = iftable->GetInterface(i)->NumDeclaredVirtualMethods();
7239 if (num_methods > 0) {
7240 StackHandleScope<2> hs2(self);
7241 const bool is_super = i < super_ifcount;
7242 const bool super_interface = is_super && extend_super_iftable;
7243 // We don't actually create or fill these tables for interfaces, we just copy some methods for
7244 // conflict methods. Just set this as nullptr in those cases.
7245 Handle<mirror::PointerArray> method_array(fill_tables
7246 ? hs2.NewHandle(iftable->GetMethodArray(i))
7247 : hs2.NewHandle<mirror::PointerArray>(nullptr));
7249 ArraySlice<ArtMethod> input_virtual_methods;
7250 ScopedNullHandle<mirror::PointerArray> null_handle;
7251 Handle<mirror::PointerArray> input_vtable_array(null_handle);
7252 int32_t input_array_length = 0;
7254 // TODO Cleanup Needed: In the presence of default methods this optimization is rather dirty
7255 // and confusing. Default methods should always look through all the superclasses
7256 // because they are the last choice of an implementation. We get around this by looking
7257 // at the super-classes iftable methods (copied into method_array previously) when we are
7258 // looking for the implementation of a super-interface method but that is rather dirty.
7259 bool using_virtuals;
7260 if (super_interface || is_interface) {
7261 // If we are overwriting a super class interface, try to only virtual methods instead of the
7263 using_virtuals = true;
7264 input_virtual_methods = klass->GetDeclaredMethodsSlice(image_pointer_size_);
7265 input_array_length = input_virtual_methods.size();
7267 // For a new interface, however, we need the whole vtable in case a new
7268 // interface method is implemented in the whole superclass.
7269 using_virtuals = false;
7270 DCHECK(vtable.Get() != nullptr);
7271 input_vtable_array = vtable;
7272 input_array_length = input_vtable_array->GetLength();
7275 // For each method in interface
7276 for (size_t j = 0; j < num_methods; ++j) {
7277 auto* interface_method = iftable->GetInterface(i)->GetVirtualMethod(j, image_pointer_size_);
7278 MethodNameAndSignatureComparator interface_name_comparator(
7279 interface_method->GetInterfaceMethodIfProxy(image_pointer_size_));
7280 uint32_t imt_index = ImTable::GetImtIndex(interface_method);
7281 ArtMethod** imt_ptr = &out_imt[imt_index];
7282 // For each method listed in the interface's method list, find the
7283 // matching method in our class's method list. We want to favor the
7284 // subclass over the superclass, which just requires walking
7285 // back from the end of the vtable. (This only matters if the
7286 // superclass defines a private method and this class redefines
7287 // it -- otherwise it would use the same vtable slot. In .dex files
7288 // those don't end up in the virtual method table, so it shouldn't
7289 // matter which direction we go. We walk it backward anyway.)
7291 // To find defaults we need to do the same but also go over interfaces.
7292 bool found_impl = false;
7293 ArtMethod* vtable_impl = nullptr;
7294 for (int32_t k = input_array_length - 1; k >= 0; --k) {
7295 ArtMethod* vtable_method = using_virtuals ?
7296 &input_virtual_methods[k] :
7297 input_vtable_array->GetElementPtrSize<ArtMethod*>(k, image_pointer_size_);
7298 ArtMethod* vtable_method_for_name_comparison =
7299 vtable_method->GetInterfaceMethodIfProxy(image_pointer_size_);
7300 if (interface_name_comparator.HasSameNameAndSignature(
7301 vtable_method_for_name_comparison)) {
7302 if (!vtable_method->IsAbstract() && !vtable_method->IsPublic()) {
7303 // Must do EndAssertNoThreadSuspension before throw since the throw can cause
7305 self->EndAssertNoThreadSuspension(old_cause);
7306 ThrowIllegalAccessError(klass.Get(),
7307 "Method '%s' implementing interface method '%s' is not public",
7308 vtable_method->PrettyMethod().c_str(),
7309 interface_method->PrettyMethod().c_str());
7311 } else if (UNLIKELY(vtable_method->IsOverridableByDefaultMethod())) {
7312 // We might have a newer, better, default method for this, so we just skip it. If we
7313 // are still using this we will select it again when scanning for default methods. To
7314 // obviate the need to copy the method again we will make a note that we already found
7316 // TODO This should be much cleaner.
7317 vtable_impl = vtable_method;
7321 if (LIKELY(fill_tables)) {
7322 method_array->SetElementPtrSize(j, vtable_method, image_pointer_size_);
7323 // Place method in imt if entry is empty, place conflict otherwise.
7324 SetIMTRef(unimplemented_method,
7325 imt_conflict_method,
7327 /*out*/out_new_conflict,
7334 // Continue on to the next method if we are done.
7335 if (LIKELY(found_impl)) {
7337 } else if (LIKELY(super_interface)) {
7338 // Don't look for a default implementation when the super-method is implemented directly
7341 // See if we can use the superclasses method and skip searching everything else.
7342 // Note: !found_impl && super_interface
7343 CHECK(extend_super_iftable);
7344 // If this is a super_interface method it is possible we shouldn't override it because a
7345 // superclass could have implemented it directly. We get the method the superclass used
7346 // to implement this to know if we can override it with a default method. Doing this is
7347 // safe since we know that the super_iftable is filled in so we can simply pull it from
7348 // there. We don't bother if this is not a super-classes interface since in that case we
7349 // have scanned the entire vtable anyway and would have found it.
7350 // TODO This is rather dirty but it is faster than searching through the entire vtable
7352 ArtMethod* supers_method =
7353 method_array->GetElementPtrSize<ArtMethod*>(j, image_pointer_size_);
7354 DCHECK(supers_method != nullptr);
7355 DCHECK(interface_name_comparator.HasSameNameAndSignature(supers_method));
7356 if (LIKELY(!supers_method->IsOverridableByDefaultMethod())) {
7357 // The method is not overridable by a default method (i.e. it is directly implemented
7358 // in some class). Therefore move onto the next interface method.
7361 // If the super-classes method is override-able by a default method we need to keep
7362 // track of it since though it is override-able it is not guaranteed to be 'overridden'.
7363 // If it turns out not to be overridden and we did not keep track of it we might add it
7364 // to the vtable twice, causing corruption (vtable entries having inconsistent and
7365 // illegal states, incorrect vtable size, and incorrect or inconsistent iftable entries)
7366 // in this class and any subclasses.
7367 DCHECK(vtable_impl == nullptr || vtable_impl == supers_method)
7368 << "vtable_impl was " << ArtMethod::PrettyMethod(vtable_impl)
7369 << " and not 'nullptr' or "
7370 << supers_method->PrettyMethod()
7371 << " as expected. IFTable appears to be corrupt!";
7372 vtable_impl = supers_method;
7375 // If we haven't found it yet we should search through the interfaces for default methods.
7376 ArtMethod* current_method = helper.FindMethod(interface_method,
7377 interface_name_comparator,
7379 if (LIKELY(fill_tables)) {
7380 if (current_method == nullptr && !super_interface) {
7381 // We could not find an implementation for this method and since it is a brand new
7382 // interface we searched the entire vtable (and all default methods) for an
7383 // implementation but couldn't find one. We therefore need to make a miranda method.
7384 current_method = helper.GetOrCreateMirandaMethod(interface_method,
7385 interface_name_comparator);
7388 if (current_method != nullptr) {
7389 // We found a default method implementation. Record it in the iftable and IMT.
7390 method_array->SetElementPtrSize(j, current_method, image_pointer_size_);
7391 SetIMTRef(unimplemented_method,
7392 imt_conflict_method,
7394 /*out*/out_new_conflict,
7398 } // For each method in interface end.
7399 } // if (num_methods > 0)
7400 } // For each interface.
7401 // TODO don't extend virtuals of interface unless necessary (when is it?).
7402 if (helper.HasNewVirtuals()) {
7403 LengthPrefixedArray<ArtMethod>* old_methods = kIsDebugBuild ? klass->GetMethodsPtr() : nullptr;
7404 helper.ReallocMethods(); // No return value to check. Native allocation failure aborts.
7405 LengthPrefixedArray<ArtMethod>* methods = kIsDebugBuild ? klass->GetMethodsPtr() : nullptr;
7407 // Done copying methods, they are all roots in the class now, so we can end the no thread
7408 // suspension assert.
7409 self->EndAssertNoThreadSuspension(old_cause);
7412 vtable.Assign(helper.UpdateVtable(default_translations, vtable.Get()));
7413 if (UNLIKELY(vtable.Get() == nullptr)) {
7414 // The helper has already called self->AssertPendingOOMException();
7417 helper.UpdateIfTable(iftable);
7418 helper.UpdateIMT(out_imt);
7421 helper.CheckNoStaleMethodsInDexCache();
7422 helper.ClobberOldMethods(old_methods, methods);
7424 self->EndAssertNoThreadSuspension(old_cause);
7426 if (kIsDebugBuild && !is_interface) {
7427 SanityCheckVTable(self, klass, image_pointer_size_);
7432 bool ClassLinker::LinkInstanceFields(Thread* self, Handle<mirror::Class> klass) {
7433 CHECK(klass.Get() != nullptr);
7434 return LinkFields(self, klass, false, nullptr);
7437 bool ClassLinker::LinkStaticFields(Thread* self, Handle<mirror::Class> klass, size_t* class_size) {
7438 CHECK(klass.Get() != nullptr);
7439 return LinkFields(self, klass, true, class_size);
7442 struct LinkFieldsComparator {
7443 explicit LinkFieldsComparator() REQUIRES_SHARED(Locks::mutator_lock_) {
7445 // No thread safety analysis as will be called from STL. Checked lock held in constructor.
7446 bool operator()(ArtField* field1, ArtField* field2)
7447 NO_THREAD_SAFETY_ANALYSIS {
7448 // First come reference fields, then 64-bit, then 32-bit, and then 16-bit, then finally 8-bit.
7449 Primitive::Type type1 = field1->GetTypeAsPrimitiveType();
7450 Primitive::Type type2 = field2->GetTypeAsPrimitiveType();
7451 if (type1 != type2) {
7452 if (type1 == Primitive::kPrimNot) {
7453 // Reference always goes first.
7456 if (type2 == Primitive::kPrimNot) {
7457 // Reference always goes first.
7460 size_t size1 = Primitive::ComponentSize(type1);
7461 size_t size2 = Primitive::ComponentSize(type2);
7462 if (size1 != size2) {
7463 // Larger primitive types go first.
7464 return size1 > size2;
7466 // Primitive types differ but sizes match. Arbitrarily order by primitive type.
7467 return type1 < type2;
7469 // Same basic group? Then sort by dex field index. This is guaranteed to be sorted
7470 // by name and for equal names by type id index.
7471 // NOTE: This works also for proxies. Their static fields are assigned appropriate indexes.
7472 return field1->GetDexFieldIndex() < field2->GetDexFieldIndex();
7476 bool ClassLinker::LinkFields(Thread* self,
7477 Handle<mirror::Class> klass,
7479 size_t* class_size) {
7480 self->AllowThreadSuspension();
7481 const size_t num_fields = is_static ? klass->NumStaticFields() : klass->NumInstanceFields();
7482 LengthPrefixedArray<ArtField>* const fields = is_static ? klass->GetSFieldsPtr() :
7483 klass->GetIFieldsPtr();
7485 // Initialize field_offset
7486 MemberOffset field_offset(0);
7488 field_offset = klass->GetFirstReferenceStaticFieldOffsetDuringLinking(image_pointer_size_);
7490 ObjPtr<mirror::Class> super_class = klass->GetSuperClass();
7491 if (super_class != nullptr) {
7492 CHECK(super_class->IsResolved())
7493 << klass->PrettyClass() << " " << super_class->PrettyClass();
7494 field_offset = MemberOffset(super_class->GetObjectSize());
7498 CHECK_EQ(num_fields == 0, fields == nullptr) << klass->PrettyClass();
7500 // we want a relatively stable order so that adding new fields
7501 // minimizes disruption of C++ version such as Class and Method.
7503 // The overall sort order order is:
7504 // 1) All object reference fields, sorted alphabetically.
7505 // 2) All java long (64-bit) integer fields, sorted alphabetically.
7506 // 3) All java double (64-bit) floating point fields, sorted alphabetically.
7507 // 4) All java int (32-bit) integer fields, sorted alphabetically.
7508 // 5) All java float (32-bit) floating point fields, sorted alphabetically.
7509 // 6) All java char (16-bit) integer fields, sorted alphabetically.
7510 // 7) All java short (16-bit) integer fields, sorted alphabetically.
7511 // 8) All java boolean (8-bit) integer fields, sorted alphabetically.
7512 // 9) All java byte (8-bit) integer fields, sorted alphabetically.
7514 // Once the fields are sorted in this order we will attempt to fill any gaps that might be present
7515 // in the memory layout of the structure. See ShuffleForward for how this is done.
7516 std::deque<ArtField*> grouped_and_sorted_fields;
7517 const char* old_no_suspend_cause = self->StartAssertNoThreadSuspension(
7518 "Naked ArtField references in deque");
7519 for (size_t i = 0; i < num_fields; i++) {
7520 grouped_and_sorted_fields.push_back(&fields->At(i));
7522 std::sort(grouped_and_sorted_fields.begin(), grouped_and_sorted_fields.end(),
7523 LinkFieldsComparator());
7525 // References should be at the front.
7526 size_t current_field = 0;
7527 size_t num_reference_fields = 0;
7530 for (; current_field < num_fields; current_field++) {
7531 ArtField* field = grouped_and_sorted_fields.front();
7532 Primitive::Type type = field->GetTypeAsPrimitiveType();
7533 bool isPrimitive = type != Primitive::kPrimNot;
7535 break; // past last reference, move on to the next phase
7537 if (UNLIKELY(!IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>(
7538 field_offset.Uint32Value()))) {
7539 MemberOffset old_offset = field_offset;
7540 field_offset = MemberOffset(RoundUp(field_offset.Uint32Value(), 4));
7541 AddFieldGap(old_offset.Uint32Value(), field_offset.Uint32Value(), &gaps);
7543 DCHECK_ALIGNED(field_offset.Uint32Value(), sizeof(mirror::HeapReference<mirror::Object>));
7544 grouped_and_sorted_fields.pop_front();
7545 num_reference_fields++;
7546 field->SetOffset(field_offset);
7547 field_offset = MemberOffset(field_offset.Uint32Value() +
7548 sizeof(mirror::HeapReference<mirror::Object>));
7550 // Gaps are stored as a max heap which means that we must shuffle from largest to smallest
7551 // otherwise we could end up with suboptimal gap fills.
7552 ShuffleForward<8>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps);
7553 ShuffleForward<4>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps);
7554 ShuffleForward<2>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps);
7555 ShuffleForward<1>(¤t_field, &field_offset, &grouped_and_sorted_fields, &gaps);
7556 CHECK(grouped_and_sorted_fields.empty()) << "Missed " << grouped_and_sorted_fields.size() <<
7558 self->EndAssertNoThreadSuspension(old_no_suspend_cause);
7560 // We lie to the GC about the java.lang.ref.Reference.referent field, so it doesn't scan it.
7561 if (!is_static && klass->DescriptorEquals("Ljava/lang/ref/Reference;")) {
7562 // We know there are no non-reference fields in the Reference classes, and we know
7563 // that 'referent' is alphabetically last, so this is easy...
7564 CHECK_EQ(num_reference_fields, num_fields) << klass->PrettyClass();
7565 CHECK_STREQ(fields->At(num_fields - 1).GetName(), "referent")
7566 << klass->PrettyClass();
7567 --num_reference_fields;
7570 size_t size = field_offset.Uint32Value();
7573 klass->SetNumReferenceStaticFields(num_reference_fields);
7576 klass->SetNumReferenceInstanceFields(num_reference_fields);
7577 ObjPtr<mirror::Class> super_class = klass->GetSuperClass();
7578 if (num_reference_fields == 0 || super_class == nullptr) {
7579 // object has one reference field, klass, but we ignore it since we always visit the class.
7580 // super_class is null iff the class is java.lang.Object.
7581 if (super_class == nullptr ||
7582 (super_class->GetClassFlags() & mirror::kClassFlagNoReferenceFields) != 0) {
7583 klass->SetClassFlags(klass->GetClassFlags() | mirror::kClassFlagNoReferenceFields);
7586 if (kIsDebugBuild) {
7587 DCHECK_EQ(super_class == nullptr, klass->DescriptorEquals("Ljava/lang/Object;"));
7588 size_t total_reference_instance_fields = 0;
7589 ObjPtr<mirror::Class> cur_super = klass.Get();
7590 while (cur_super != nullptr) {
7591 total_reference_instance_fields += cur_super->NumReferenceInstanceFieldsDuringLinking();
7592 cur_super = cur_super->GetSuperClass();
7594 if (super_class == nullptr) {
7595 CHECK_EQ(total_reference_instance_fields, 1u) << klass->PrettyDescriptor();
7597 // Check that there is at least num_reference_fields other than Object.class.
7598 CHECK_GE(total_reference_instance_fields, 1u + num_reference_fields)
7599 << klass->PrettyClass();
7602 if (!klass->IsVariableSize()) {
7604 DCHECK_GE(size, sizeof(mirror::Object)) << klass->GetDescriptor(&temp);
7605 size_t previous_size = klass->GetObjectSize();
7606 if (previous_size != 0) {
7607 // Make sure that we didn't originally have an incorrect size.
7608 CHECK_EQ(previous_size, size) << klass->GetDescriptor(&temp);
7610 klass->SetObjectSize(size);
7614 if (kIsDebugBuild) {
7615 // Make sure that the fields array is ordered by name but all reference
7616 // offsets are at the beginning as far as alignment allows.
7617 MemberOffset start_ref_offset = is_static
7618 ? klass->GetFirstReferenceStaticFieldOffsetDuringLinking(image_pointer_size_)
7619 : klass->GetFirstReferenceInstanceFieldOffset();
7620 MemberOffset end_ref_offset(start_ref_offset.Uint32Value() +
7621 num_reference_fields *
7622 sizeof(mirror::HeapReference<mirror::Object>));
7623 MemberOffset current_ref_offset = start_ref_offset;
7624 for (size_t i = 0; i < num_fields; i++) {
7625 ArtField* field = &fields->At(i);
7626 VLOG(class_linker) << "LinkFields: " << (is_static ? "static" : "instance")
7627 << " class=" << klass->PrettyClass() << " field=" << field->PrettyField()
7628 << " offset=" << field->GetOffsetDuringLinking();
7630 ArtField* const prev_field = &fields->At(i - 1);
7631 // NOTE: The field names can be the same. This is not possible in the Java language
7632 // but it's valid Java/dex bytecode and for example proguard can generate such bytecode.
7633 DCHECK_LE(strcmp(prev_field->GetName(), field->GetName()), 0);
7635 Primitive::Type type = field->GetTypeAsPrimitiveType();
7636 bool is_primitive = type != Primitive::kPrimNot;
7637 if (klass->DescriptorEquals("Ljava/lang/ref/Reference;") &&
7638 strcmp("referent", field->GetName()) == 0) {
7639 is_primitive = true; // We lied above, so we have to expect a lie here.
7641 MemberOffset offset = field->GetOffsetDuringLinking();
7643 if (offset.Uint32Value() < end_ref_offset.Uint32Value()) {
7644 // Shuffled before references.
7645 size_t type_size = Primitive::ComponentSize(type);
7646 CHECK_LT(type_size, sizeof(mirror::HeapReference<mirror::Object>));
7647 CHECK_LT(offset.Uint32Value(), start_ref_offset.Uint32Value());
7648 CHECK_LE(offset.Uint32Value() + type_size, start_ref_offset.Uint32Value());
7649 CHECK(!IsAligned<sizeof(mirror::HeapReference<mirror::Object>)>(offset.Uint32Value()));
7652 CHECK_EQ(current_ref_offset.Uint32Value(), offset.Uint32Value());
7653 current_ref_offset = MemberOffset(current_ref_offset.Uint32Value() +
7654 sizeof(mirror::HeapReference<mirror::Object>));
7657 CHECK_EQ(current_ref_offset.Uint32Value(), end_ref_offset.Uint32Value());
7662 // Set the bitmap of reference instance field offsets.
7663 void ClassLinker::CreateReferenceInstanceOffsets(Handle<mirror::Class> klass) {
7664 uint32_t reference_offsets = 0;
7665 ObjPtr<mirror::Class> super_class = klass->GetSuperClass();
7666 // Leave the reference offsets as 0 for mirror::Object (the class field is handled specially).
7667 if (super_class != nullptr) {
7668 reference_offsets = super_class->GetReferenceInstanceOffsets();
7669 // Compute reference offsets unless our superclass overflowed.
7670 if (reference_offsets != mirror::Class::kClassWalkSuper) {
7671 size_t num_reference_fields = klass->NumReferenceInstanceFieldsDuringLinking();
7672 if (num_reference_fields != 0u) {
7673 // All of the fields that contain object references are guaranteed be grouped in memory
7674 // starting at an appropriately aligned address after super class object data.
7675 uint32_t start_offset = RoundUp(super_class->GetObjectSize(),
7676 sizeof(mirror::HeapReference<mirror::Object>));
7677 uint32_t start_bit = (start_offset - mirror::kObjectHeaderSize) /
7678 sizeof(mirror::HeapReference<mirror::Object>);
7679 if (start_bit + num_reference_fields > 32) {
7680 reference_offsets = mirror::Class::kClassWalkSuper;
7682 reference_offsets |= (0xffffffffu << start_bit) &
7683 (0xffffffffu >> (32 - (start_bit + num_reference_fields)));
7688 klass->SetReferenceInstanceOffsets(reference_offsets);
7691 mirror::String* ClassLinker::ResolveString(const DexFile& dex_file,
7692 dex::StringIndex string_idx,
7693 Handle<mirror::DexCache> dex_cache) {
7694 DCHECK(dex_cache.Get() != nullptr);
7695 Thread::PoisonObjectPointersIfDebug();
7696 ObjPtr<mirror::String> resolved = dex_cache->GetResolvedString(string_idx);
7697 if (resolved != nullptr) {
7698 return resolved.Ptr();
7700 uint32_t utf16_length;
7701 const char* utf8_data = dex_file.StringDataAndUtf16LengthByIdx(string_idx, &utf16_length);
7702 ObjPtr<mirror::String> string = intern_table_->InternStrong(utf16_length, utf8_data);
7703 dex_cache->SetResolvedString(string_idx, string);
7704 return string.Ptr();
7707 mirror::String* ClassLinker::LookupString(const DexFile& dex_file,
7708 dex::StringIndex string_idx,
7709 Handle<mirror::DexCache> dex_cache) {
7710 DCHECK(dex_cache.Get() != nullptr);
7711 ObjPtr<mirror::String> resolved = dex_cache->GetResolvedString(string_idx);
7712 if (resolved != nullptr) {
7713 return resolved.Ptr();
7715 uint32_t utf16_length;
7716 const char* utf8_data = dex_file.StringDataAndUtf16LengthByIdx(string_idx, &utf16_length);
7717 ObjPtr<mirror::String> string =
7718 intern_table_->LookupStrong(Thread::Current(), utf16_length, utf8_data);
7719 if (string != nullptr) {
7720 dex_cache->SetResolvedString(string_idx, string);
7722 return string.Ptr();
7725 ObjPtr<mirror::Class> ClassLinker::LookupResolvedType(const DexFile& dex_file,
7726 dex::TypeIndex type_idx,
7727 ObjPtr<mirror::DexCache> dex_cache,
7728 ObjPtr<mirror::ClassLoader> class_loader) {
7729 ObjPtr<mirror::Class> type = dex_cache->GetResolvedType(type_idx);
7730 if (type == nullptr) {
7731 const char* descriptor = dex_file.StringByTypeIdx(type_idx);
7732 DCHECK_NE(*descriptor, '\0') << "descriptor is empty string";
7733 if (descriptor[1] == '\0') {
7734 // only the descriptors of primitive types should be 1 character long, also avoid class lookup
7735 // for primitive classes that aren't backed by dex files.
7736 type = FindPrimitiveClass(descriptor[0]);
7738 Thread* const self = Thread::Current();
7739 DCHECK(self != nullptr);
7740 const size_t hash = ComputeModifiedUtf8Hash(descriptor);
7741 // Find the class in the loaded classes table.
7742 type = LookupClass(self, descriptor, hash, class_loader.Ptr());
7745 if (type != nullptr && type->IsResolved()) {
7751 mirror::Class* ClassLinker::ResolveType(const DexFile& dex_file,
7752 dex::TypeIndex type_idx,
7753 ObjPtr<mirror::Class> referrer) {
7754 StackHandleScope<2> hs(Thread::Current());
7755 Handle<mirror::DexCache> dex_cache(hs.NewHandle(referrer->GetDexCache()));
7756 Handle<mirror::ClassLoader> class_loader(hs.NewHandle(referrer->GetClassLoader()));
7757 return ResolveType(dex_file, type_idx, dex_cache, class_loader);
7760 mirror::Class* ClassLinker::ResolveType(const DexFile& dex_file,
7761 dex::TypeIndex type_idx,
7762 Handle<mirror::DexCache> dex_cache,
7763 Handle<mirror::ClassLoader> class_loader) {
7764 DCHECK(dex_cache.Get() != nullptr);
7765 Thread::PoisonObjectPointersIfDebug();
7766 ObjPtr<mirror::Class> resolved = dex_cache->GetResolvedType(type_idx);
7767 if (resolved == nullptr) {
7768 Thread* self = Thread::Current();
7769 const char* descriptor = dex_file.StringByTypeIdx(type_idx);
7770 resolved = FindClass(self, descriptor, class_loader);
7771 if (resolved != nullptr) {
7772 // TODO: we used to throw here if resolved's class loader was not the
7773 // boot class loader. This was to permit different classes with the
7774 // same name to be loaded simultaneously by different loaders
7775 dex_cache->SetResolvedType(type_idx, resolved);
7777 CHECK(self->IsExceptionPending())
7778 << "Expected pending exception for failed resolution of: " << descriptor;
7779 // Convert a ClassNotFoundException to a NoClassDefFoundError.
7780 StackHandleScope<1> hs(self);
7781 Handle<mirror::Throwable> cause(hs.NewHandle(self->GetException()));
7782 if (cause->InstanceOf(GetClassRoot(kJavaLangClassNotFoundException))) {
7783 DCHECK(resolved == nullptr); // No Handle needed to preserve resolved.
7784 self->ClearException();
7785 ThrowNoClassDefFoundError("Failed resolution of: %s", descriptor);
7786 self->GetException()->SetCause(cause.Get());
7790 DCHECK((resolved == nullptr) || resolved->IsResolved())
7791 << resolved->PrettyDescriptor() << " " << resolved->GetStatus();
7792 return resolved.Ptr();
7795 template <ClassLinker::ResolveMode kResolveMode>
7796 ArtMethod* ClassLinker::ResolveMethod(const DexFile& dex_file,
7797 uint32_t method_idx,
7798 Handle<mirror::DexCache> dex_cache,
7799 Handle<mirror::ClassLoader> class_loader,
7800 ArtMethod* referrer,
7802 DCHECK(dex_cache.Get() != nullptr);
7803 // Check for hit in the dex cache.
7804 ArtMethod* resolved = dex_cache->GetResolvedMethod(method_idx, image_pointer_size_);
7805 Thread::PoisonObjectPointersIfDebug();
7806 if (resolved != nullptr && !resolved->IsRuntimeMethod()) {
7807 DCHECK(resolved->GetDeclaringClassUnchecked() != nullptr) << resolved->GetDexMethodIndex();
7808 if (kResolveMode == ClassLinker::kForceICCECheck) {
7809 if (resolved->CheckIncompatibleClassChange(type)) {
7810 ThrowIncompatibleClassChangeError(type, resolved->GetInvokeType(), resolved, referrer);
7816 // Fail, get the declaring class.
7817 const DexFile::MethodId& method_id = dex_file.GetMethodId(method_idx);
7818 ObjPtr<mirror::Class> klass = ResolveType(dex_file, method_id.class_idx_, dex_cache, class_loader);
7819 if (klass == nullptr) {
7820 DCHECK(Thread::Current()->IsExceptionPending());
7823 // Scan using method_idx, this saves string compares but will only hit for matching dex
7826 case kDirect: // Fall-through.
7828 resolved = klass->FindDirectMethod(dex_cache.Get(), method_idx, image_pointer_size_);
7829 DCHECK(resolved == nullptr || resolved->GetDeclaringClassUnchecked() != nullptr);
7832 // We have to check whether the method id really belongs to an interface (dex static bytecode
7833 // constraint A15). Otherwise you must not invoke-interface on it.
7835 // This is not symmetric to A12-A14 (direct, static, virtual), as using FindInterfaceMethod
7836 // assumes that the given type is an interface, and will check the interface table if the
7837 // method isn't declared in the class. So it may find an interface method (usually by name
7838 // in the handling below, but we do the constraint check early). In that case,
7839 // CheckIncompatibleClassChange will succeed (as it is called on an interface method)
7845 // class A implements I {
7848 // class B extends A {
7851 // invoke-interface B.foo
7852 // -> FindInterfaceMethod finds I.foo (interface method), not A.foo (miranda method)
7853 if (UNLIKELY(!klass->IsInterface())) {
7854 ThrowIncompatibleClassChangeError(klass,
7855 "Found class %s, but interface was expected",
7856 klass->PrettyDescriptor().c_str());
7859 resolved = klass->FindInterfaceMethod(dex_cache.Get(), method_idx, image_pointer_size_);
7860 DCHECK(resolved == nullptr || resolved->GetDeclaringClass()->IsInterface());
7864 if (klass->IsInterface()) {
7865 resolved = klass->FindInterfaceMethod(dex_cache.Get(), method_idx, image_pointer_size_);
7867 resolved = klass->FindVirtualMethod(dex_cache.Get(), method_idx, image_pointer_size_);
7871 resolved = klass->FindVirtualMethod(dex_cache.Get(), method_idx, image_pointer_size_);
7874 LOG(FATAL) << "Unreachable - invocation type: " << type;
7877 if (resolved == nullptr) {
7878 // Search by name, which works across dex files.
7879 const char* name = dex_file.StringDataByIdx(method_id.name_idx_);
7880 const Signature signature = dex_file.GetMethodSignature(method_id);
7882 case kDirect: // Fall-through.
7884 resolved = klass->FindDirectMethod(name, signature, image_pointer_size_);
7885 DCHECK(resolved == nullptr || resolved->GetDeclaringClassUnchecked() != nullptr);
7888 resolved = klass->FindInterfaceMethod(name, signature, image_pointer_size_);
7889 DCHECK(resolved == nullptr || resolved->GetDeclaringClass()->IsInterface());
7892 if (klass->IsInterface()) {
7893 resolved = klass->FindInterfaceMethod(name, signature, image_pointer_size_);
7895 resolved = klass->FindVirtualMethod(name, signature, image_pointer_size_);
7899 resolved = klass->FindVirtualMethod(name, signature, image_pointer_size_);
7903 // If we found a method, check for incompatible class changes.
7904 if (LIKELY(resolved != nullptr && !resolved->CheckIncompatibleClassChange(type))) {
7905 // Be a good citizen and update the dex cache to speed subsequent calls.
7906 dex_cache->SetResolvedMethod(method_idx, resolved, image_pointer_size_);
7909 // If we had a method, it's an incompatible-class-change error.
7910 if (resolved != nullptr) {
7911 ThrowIncompatibleClassChangeError(type, resolved->GetInvokeType(), resolved, referrer);
7913 // We failed to find the method which means either an access error, an incompatible class
7914 // change, or no such method. First try to find the method among direct and virtual methods.
7915 const char* name = dex_file.StringDataByIdx(method_id.name_idx_);
7916 const Signature signature = dex_file.GetMethodSignature(method_id);
7920 resolved = klass->FindVirtualMethod(name, signature, image_pointer_size_);
7921 // Note: kDirect and kStatic are also mutually exclusive, but in that case we would
7922 // have had a resolved method before, which triggers the "true" branch above.
7927 resolved = klass->FindDirectMethod(name, signature, image_pointer_size_);
7931 // If we found something, check that it can be accessed by the referrer.
7932 bool exception_generated = false;
7933 if (resolved != nullptr && referrer != nullptr) {
7934 ObjPtr<mirror::Class> methods_class = resolved->GetDeclaringClass();
7935 ObjPtr<mirror::Class> referring_class = referrer->GetDeclaringClass();
7936 if (!referring_class->CanAccess(methods_class)) {
7937 ThrowIllegalAccessErrorClassForMethodDispatch(referring_class,
7941 exception_generated = true;
7942 } else if (!referring_class->CanAccessMember(methods_class, resolved->GetAccessFlags())) {
7943 ThrowIllegalAccessErrorMethod(referring_class, resolved);
7944 exception_generated = true;
7947 if (!exception_generated) {
7948 // Otherwise, throw an IncompatibleClassChangeError if we found something, and check
7949 // interface methods and throw if we find the method there. If we find nothing, throw a
7950 // NoSuchMethodError.
7954 if (resolved != nullptr) {
7955 ThrowIncompatibleClassChangeError(type, kVirtual, resolved, referrer);
7957 resolved = klass->FindInterfaceMethod(name, signature, image_pointer_size_);
7958 if (resolved != nullptr) {
7959 ThrowIncompatibleClassChangeError(type, kInterface, resolved, referrer);
7961 ThrowNoSuchMethodError(type, klass, name, signature);
7966 if (resolved != nullptr) {
7967 ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer);
7969 resolved = klass->FindVirtualMethod(name, signature, image_pointer_size_);
7970 if (resolved != nullptr) {
7971 ThrowIncompatibleClassChangeError(type, kVirtual, resolved, referrer);
7973 ThrowNoSuchMethodError(type, klass, name, signature);
7978 if (resolved != nullptr) {
7979 ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer);
7981 ThrowNoSuchMethodError(type, klass, name, signature);
7985 if (resolved != nullptr) {
7986 ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer);
7988 resolved = klass->FindInterfaceMethod(name, signature, image_pointer_size_);
7989 if (resolved != nullptr) {
7990 ThrowIncompatibleClassChangeError(type, kInterface, resolved, referrer);
7992 ThrowNoSuchMethodError(type, klass, name, signature);
7999 Thread::Current()->AssertPendingException();
8004 ArtMethod* ClassLinker::ResolveMethodWithoutInvokeType(const DexFile& dex_file,
8005 uint32_t method_idx,
8006 Handle<mirror::DexCache> dex_cache,
8007 Handle<mirror::ClassLoader> class_loader) {
8008 ArtMethod* resolved = dex_cache->GetResolvedMethod(method_idx, image_pointer_size_);
8009 Thread::PoisonObjectPointersIfDebug();
8010 if (resolved != nullptr && !resolved->IsRuntimeMethod()) {
8011 DCHECK(resolved->GetDeclaringClassUnchecked() != nullptr) << resolved->GetDexMethodIndex();
8014 // Fail, get the declaring class.
8015 const DexFile::MethodId& method_id = dex_file.GetMethodId(method_idx);
8016 ObjPtr<mirror::Class> klass = ResolveType(dex_file, method_id.class_idx_, dex_cache, class_loader);
8017 if (klass == nullptr) {
8018 Thread::Current()->AssertPendingException();
8021 if (klass->IsInterface()) {
8022 LOG(FATAL) << "ResolveAmbiguousMethod: unexpected method in interface: "
8023 << klass->PrettyClass();
8027 // Search both direct and virtual methods
8028 resolved = klass->FindDirectMethod(dex_cache.Get(), method_idx, image_pointer_size_);
8029 if (resolved == nullptr) {
8030 resolved = klass->FindVirtualMethod(dex_cache.Get(), method_idx, image_pointer_size_);
8036 ArtField* ClassLinker::ResolveField(const DexFile& dex_file,
8038 Handle<mirror::DexCache> dex_cache,
8039 Handle<mirror::ClassLoader> class_loader,
8041 DCHECK(dex_cache.Get() != nullptr);
8042 ArtField* resolved = dex_cache->GetResolvedField(field_idx, image_pointer_size_);
8043 Thread::PoisonObjectPointersIfDebug();
8044 if (resolved != nullptr) {
8047 const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx);
8048 Thread* const self = Thread::Current();
8049 ObjPtr<mirror::Class> klass = ResolveType(dex_file, field_id.class_idx_, dex_cache, class_loader);
8050 if (klass == nullptr) {
8051 DCHECK(Thread::Current()->IsExceptionPending());
8056 resolved = mirror::Class::FindStaticField(self, klass, dex_cache.Get(), field_idx);
8058 resolved = klass->FindInstanceField(dex_cache.Get(), field_idx);
8061 if (resolved == nullptr) {
8062 const char* name = dex_file.GetFieldName(field_id);
8063 const char* type = dex_file.GetFieldTypeDescriptor(field_id);
8065 resolved = mirror::Class::FindStaticField(self, klass, name, type);
8067 resolved = klass->FindInstanceField(name, type);
8069 if (resolved == nullptr) {
8070 ThrowNoSuchFieldError(is_static ? "static " : "instance ", klass, type, name);
8074 dex_cache->SetResolvedField(field_idx, resolved, image_pointer_size_);
8078 ArtField* ClassLinker::ResolveFieldJLS(const DexFile& dex_file,
8080 Handle<mirror::DexCache> dex_cache,
8081 Handle<mirror::ClassLoader> class_loader) {
8082 DCHECK(dex_cache.Get() != nullptr);
8083 ArtField* resolved = dex_cache->GetResolvedField(field_idx, image_pointer_size_);
8084 Thread::PoisonObjectPointersIfDebug();
8085 if (resolved != nullptr) {
8088 const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx);
8089 Thread* self = Thread::Current();
8090 ObjPtr<mirror::Class> klass(ResolveType(dex_file, field_id.class_idx_, dex_cache, class_loader));
8091 if (klass == nullptr) {
8092 DCHECK(Thread::Current()->IsExceptionPending());
8096 StringPiece name(dex_file.StringDataByIdx(field_id.name_idx_));
8097 StringPiece type(dex_file.StringDataByIdx(
8098 dex_file.GetTypeId(field_id.type_idx_).descriptor_idx_));
8099 resolved = mirror::Class::FindField(self, klass, name, type);
8100 if (resolved != nullptr) {
8101 dex_cache->SetResolvedField(field_idx, resolved, image_pointer_size_);
8103 ThrowNoSuchFieldError("", klass, type, name);
8108 mirror::MethodType* ClassLinker::ResolveMethodType(const DexFile& dex_file,
8110 Handle<mirror::DexCache> dex_cache,
8111 Handle<mirror::ClassLoader> class_loader) {
8112 DCHECK(Runtime::Current()->IsMethodHandlesEnabled());
8113 DCHECK(dex_cache.Get() != nullptr);
8115 ObjPtr<mirror::MethodType> resolved = dex_cache->GetResolvedMethodType(proto_idx);
8116 if (resolved != nullptr) {
8117 return resolved.Ptr();
8120 Thread* const self = Thread::Current();
8121 StackHandleScope<4> hs(self);
8123 // First resolve the return type.
8124 const DexFile::ProtoId& proto_id = dex_file.GetProtoId(proto_idx);
8125 Handle<mirror::Class> return_type(hs.NewHandle(
8126 ResolveType(dex_file, proto_id.return_type_idx_, dex_cache, class_loader)));
8127 if (return_type.Get() == nullptr) {
8128 DCHECK(self->IsExceptionPending());
8132 // Then resolve the argument types.
8134 // TODO: Is there a better way to figure out the number of method arguments
8135 // other than by looking at the shorty ?
8136 const size_t num_method_args = strlen(dex_file.StringDataByIdx(proto_id.shorty_idx_)) - 1;
8138 ObjPtr<mirror::Class> class_type = mirror::Class::GetJavaLangClass();
8139 ObjPtr<mirror::Class> array_of_class = FindArrayClass(self, &class_type);
8140 Handle<mirror::ObjectArray<mirror::Class>> method_params(hs.NewHandle(
8141 mirror::ObjectArray<mirror::Class>::Alloc(self, array_of_class, num_method_args)));
8142 if (method_params.Get() == nullptr) {
8143 DCHECK(self->IsExceptionPending());
8147 DexFileParameterIterator it(dex_file, proto_id);
8149 MutableHandle<mirror::Class> param_class = hs.NewHandle<mirror::Class>(nullptr);
8150 for (; it.HasNext(); it.Next()) {
8151 const dex::TypeIndex type_idx = it.GetTypeIdx();
8152 param_class.Assign(ResolveType(dex_file, type_idx, dex_cache, class_loader));
8153 if (param_class.Get() == nullptr) {
8154 DCHECK(self->IsExceptionPending());
8158 method_params->Set(i++, param_class.Get());
8161 DCHECK(!it.HasNext());
8163 Handle<mirror::MethodType> type = hs.NewHandle(
8164 mirror::MethodType::Create(self, return_type, method_params));
8165 dex_cache->SetResolvedMethodType(proto_idx, type.Get());
8170 bool ClassLinker::IsQuickResolutionStub(const void* entry_point) const {
8171 return (entry_point == GetQuickResolutionStub()) ||
8172 (quick_resolution_trampoline_ == entry_point);
8175 bool ClassLinker::IsQuickToInterpreterBridge(const void* entry_point) const {
8176 return (entry_point == GetQuickToInterpreterBridge()) ||
8177 (quick_to_interpreter_bridge_trampoline_ == entry_point);
8180 bool ClassLinker::IsQuickGenericJniStub(const void* entry_point) const {
8181 return (entry_point == GetQuickGenericJniStub()) ||
8182 (quick_generic_jni_trampoline_ == entry_point);
8185 const void* ClassLinker::GetRuntimeQuickGenericJniStub() const {
8186 return GetQuickGenericJniStub();
8189 void ClassLinker::SetEntryPointsToCompiledCode(ArtMethod* method, const void* code) const {
8190 CHECK(code != nullptr);
8191 const uint8_t* base = reinterpret_cast<const uint8_t*>(code); // Base of data points at code.
8192 base -= sizeof(void*); // Move backward so that code_offset != 0.
8193 const uint32_t code_offset = sizeof(void*);
8194 OatFile::OatMethod oat_method(base, code_offset);
8195 oat_method.LinkMethod(method);
8198 void ClassLinker::SetEntryPointsToInterpreter(ArtMethod* method) const {
8199 if (!method->IsNative()) {
8200 method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge());
8202 SetEntryPointsToCompiledCode(method, GetQuickGenericJniStub());
8206 void ClassLinker::DumpForSigQuit(std::ostream& os) {
8207 ScopedObjectAccess soa(Thread::Current());
8208 ReaderMutexLock mu(soa.Self(), *Locks::classlinker_classes_lock_);
8209 os << "Zygote loaded classes=" << NumZygoteClasses() << " post zygote classes="
8210 << NumNonZygoteClasses() << "\n";
8213 class CountClassesVisitor : public ClassLoaderVisitor {
8215 CountClassesVisitor() : num_zygote_classes(0), num_non_zygote_classes(0) {}
8217 void Visit(ObjPtr<mirror::ClassLoader> class_loader)
8218 REQUIRES_SHARED(Locks::classlinker_classes_lock_, Locks::mutator_lock_) OVERRIDE {
8219 ClassTable* const class_table = class_loader->GetClassTable();
8220 if (class_table != nullptr) {
8221 num_zygote_classes += class_table->NumZygoteClasses(class_loader);
8222 num_non_zygote_classes += class_table->NumNonZygoteClasses(class_loader);
8226 size_t num_zygote_classes;
8227 size_t num_non_zygote_classes;
8230 size_t ClassLinker::NumZygoteClasses() const {
8231 CountClassesVisitor visitor;
8232 VisitClassLoaders(&visitor);
8233 return visitor.num_zygote_classes + boot_class_table_.NumZygoteClasses(nullptr);
8236 size_t ClassLinker::NumNonZygoteClasses() const {
8237 CountClassesVisitor visitor;
8238 VisitClassLoaders(&visitor);
8239 return visitor.num_non_zygote_classes + boot_class_table_.NumNonZygoteClasses(nullptr);
8242 size_t ClassLinker::NumLoadedClasses() {
8243 ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_);
8244 // Only return non zygote classes since these are the ones which apps which care about.
8245 return NumNonZygoteClasses();
8248 pid_t ClassLinker::GetClassesLockOwner() {
8249 return Locks::classlinker_classes_lock_->GetExclusiveOwnerTid();
8252 pid_t ClassLinker::GetDexLockOwner() {
8253 return Locks::dex_lock_->GetExclusiveOwnerTid();
8256 void ClassLinker::SetClassRoot(ClassRoot class_root, ObjPtr<mirror::Class> klass) {
8257 DCHECK(!init_done_);
8259 DCHECK(klass != nullptr);
8260 DCHECK(klass->GetClassLoader() == nullptr);
8262 mirror::ObjectArray<mirror::Class>* class_roots = class_roots_.Read();
8263 DCHECK(class_roots != nullptr);
8264 DCHECK(class_roots->Get(class_root) == nullptr);
8265 class_roots->Set<false>(class_root, klass);
8268 const char* ClassLinker::GetClassRootDescriptor(ClassRoot class_root) {
8269 static const char* class_roots_descriptors[] = {
8270 "Ljava/lang/Class;",
8271 "Ljava/lang/Object;",
8272 "[Ljava/lang/Class;",
8273 "[Ljava/lang/Object;",
8274 "Ljava/lang/String;",
8275 "Ljava/lang/DexCache;",
8276 "Ljava/lang/ref/Reference;",
8277 "Ljava/lang/reflect/Constructor;",
8278 "Ljava/lang/reflect/Field;",
8279 "Ljava/lang/reflect/Method;",
8280 "Ljava/lang/reflect/Proxy;",
8281 "[Ljava/lang/String;",
8282 "[Ljava/lang/reflect/Constructor;",
8283 "[Ljava/lang/reflect/Field;",
8284 "[Ljava/lang/reflect/Method;",
8285 "Ljava/lang/invoke/MethodHandleImpl;",
8286 "Ljava/lang/invoke/MethodType;",
8287 "Ljava/lang/ClassLoader;",
8288 "Ljava/lang/Throwable;",
8289 "Ljava/lang/ClassNotFoundException;",
8290 "Ljava/lang/StackTraceElement;",
8291 "Ldalvik/system/EmulatedStackFrame;",
8309 "[Ljava/lang/StackTraceElement;",
8310 "Ldalvik/system/ClassExt;",
8312 static_assert(arraysize(class_roots_descriptors) == size_t(kClassRootsMax),
8313 "Mismatch between class descriptors and class-root enum");
8315 const char* descriptor = class_roots_descriptors[class_root];
8316 CHECK(descriptor != nullptr);
8320 jobject ClassLinker::CreatePathClassLoader(Thread* self,
8321 const std::vector<const DexFile*>& dex_files) {
8322 // SOAAlreadyRunnable is protected, and we need something to add a global reference.
8323 // We could move the jobject to the callers, but all call-sites do this...
8324 ScopedObjectAccessUnchecked soa(self);
8326 // For now, create a libcore-level DexFile for each ART DexFile. This "explodes" multidex.
8327 StackHandleScope<6> hs(self);
8329 ArtField* dex_elements_field =
8330 jni::DecodeArtField(WellKnownClasses::dalvik_system_DexPathList_dexElements);
8332 Handle<mirror::Class> dex_elements_class(hs.NewHandle(dex_elements_field->GetType<true>()));
8333 DCHECK(dex_elements_class.Get() != nullptr);
8334 DCHECK(dex_elements_class->IsArrayClass());
8335 Handle<mirror::ObjectArray<mirror::Object>> h_dex_elements(hs.NewHandle(
8336 mirror::ObjectArray<mirror::Object>::Alloc(self,
8337 dex_elements_class.Get(),
8338 dex_files.size())));
8339 Handle<mirror::Class> h_dex_element_class =
8340 hs.NewHandle(dex_elements_class->GetComponentType());
8342 ArtField* element_file_field =
8343 jni::DecodeArtField(WellKnownClasses::dalvik_system_DexPathList__Element_dexFile);
8344 DCHECK_EQ(h_dex_element_class.Get(), element_file_field->GetDeclaringClass());
8346 ArtField* cookie_field = jni::DecodeArtField(WellKnownClasses::dalvik_system_DexFile_cookie);
8347 DCHECK_EQ(cookie_field->GetDeclaringClass(), element_file_field->GetType<false>());
8349 ArtField* file_name_field = jni::DecodeArtField(WellKnownClasses::dalvik_system_DexFile_fileName);
8350 DCHECK_EQ(file_name_field->GetDeclaringClass(), element_file_field->GetType<false>());
8352 // Fill the elements array.
8354 for (const DexFile* dex_file : dex_files) {
8355 StackHandleScope<4> hs2(self);
8357 // CreatePathClassLoader is only used by gtests. Index 0 of h_long_array is supposed to be the
8358 // oat file but we can leave it null.
8359 Handle<mirror::LongArray> h_long_array = hs2.NewHandle(mirror::LongArray::Alloc(
8361 kDexFileIndexStart + 1));
8362 DCHECK(h_long_array.Get() != nullptr);
8363 h_long_array->Set(kDexFileIndexStart, reinterpret_cast<intptr_t>(dex_file));
8365 Handle<mirror::Object> h_dex_file = hs2.NewHandle(
8366 cookie_field->GetDeclaringClass()->AllocObject(self));
8367 DCHECK(h_dex_file.Get() != nullptr);
8368 cookie_field->SetObject<false>(h_dex_file.Get(), h_long_array.Get());
8370 Handle<mirror::String> h_file_name = hs2.NewHandle(
8371 mirror::String::AllocFromModifiedUtf8(self, dex_file->GetLocation().c_str()));
8372 DCHECK(h_file_name.Get() != nullptr);
8373 file_name_field->SetObject<false>(h_dex_file.Get(), h_file_name.Get());
8375 Handle<mirror::Object> h_element = hs2.NewHandle(h_dex_element_class->AllocObject(self));
8376 DCHECK(h_element.Get() != nullptr);
8377 element_file_field->SetObject<false>(h_element.Get(), h_dex_file.Get());
8379 h_dex_elements->Set(index, h_element.Get());
8382 DCHECK_EQ(index, h_dex_elements->GetLength());
8384 // Create DexPathList.
8385 Handle<mirror::Object> h_dex_path_list = hs.NewHandle(
8386 dex_elements_field->GetDeclaringClass()->AllocObject(self));
8387 DCHECK(h_dex_path_list.Get() != nullptr);
8389 dex_elements_field->SetObject<false>(h_dex_path_list.Get(), h_dex_elements.Get());
8391 // Create PathClassLoader.
8392 Handle<mirror::Class> h_path_class_class = hs.NewHandle(
8393 soa.Decode<mirror::Class>(WellKnownClasses::dalvik_system_PathClassLoader));
8394 Handle<mirror::Object> h_path_class_loader = hs.NewHandle(
8395 h_path_class_class->AllocObject(self));
8396 DCHECK(h_path_class_loader.Get() != nullptr);
8398 ArtField* path_list_field =
8399 jni::DecodeArtField(WellKnownClasses::dalvik_system_BaseDexClassLoader_pathList);
8400 DCHECK(path_list_field != nullptr);
8401 path_list_field->SetObject<false>(h_path_class_loader.Get(), h_dex_path_list.Get());
8403 // Make a pretend boot-classpath.
8404 // TODO: Should we scan the image?
8405 ArtField* const parent_field =
8406 mirror::Class::FindField(self,
8407 h_path_class_loader->GetClass(),
8409 "Ljava/lang/ClassLoader;");
8410 DCHECK(parent_field != nullptr);
8411 ObjPtr<mirror::Object> boot_cl =
8412 soa.Decode<mirror::Class>(WellKnownClasses::java_lang_BootClassLoader)->AllocObject(self);
8413 parent_field->SetObject<false>(h_path_class_loader.Get(), boot_cl);
8415 // Make it a global ref and return.
8416 ScopedLocalRef<jobject> local_ref(
8417 soa.Env(), soa.Env()->AddLocalReference<jobject>(h_path_class_loader.Get()));
8418 return soa.Env()->NewGlobalRef(local_ref.get());
8421 void ClassLinker::DropFindArrayClassCache() {
8422 std::fill_n(find_array_class_cache_, kFindArrayCacheSize, GcRoot<mirror::Class>(nullptr));
8423 find_array_class_cache_next_victim_ = 0;
8426 void ClassLinker::ClearClassTableStrongRoots() const {
8427 Thread* const self = Thread::Current();
8428 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_);
8429 for (const ClassLoaderData& data : class_loaders_) {
8430 if (data.class_table != nullptr) {
8431 data.class_table->ClearStrongRoots();
8436 void ClassLinker::VisitClassLoaders(ClassLoaderVisitor* visitor) const {
8437 Thread* const self = Thread::Current();
8438 for (const ClassLoaderData& data : class_loaders_) {
8439 // Need to use DecodeJObject so that we get null for cleared JNI weak globals.
8440 ObjPtr<mirror::ClassLoader> class_loader = ObjPtr<mirror::ClassLoader>::DownCast(
8441 self->DecodeJObject(data.weak_root));
8442 if (class_loader != nullptr) {
8443 visitor->Visit(class_loader.Ptr());
8448 void ClassLinker::InsertDexFileInToClassLoader(ObjPtr<mirror::Object> dex_file,
8449 ObjPtr<mirror::ClassLoader> class_loader) {
8450 DCHECK(dex_file != nullptr);
8451 Thread* const self = Thread::Current();
8452 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_);
8453 ClassTable* const table = ClassTableForClassLoader(class_loader.Ptr());
8454 DCHECK(table != nullptr);
8455 if (table->InsertStrongRoot(dex_file) && class_loader != nullptr) {
8456 // It was not already inserted, perform the write barrier to let the GC know the class loader's
8457 // class table was modified.
8458 Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(class_loader);
8462 void ClassLinker::CleanupClassLoaders() {
8463 Thread* const self = Thread::Current();
8464 std::vector<ClassLoaderData> to_delete;
8465 // Do the delete outside the lock to avoid lock violation in jit code cache.
8467 WriterMutexLock mu(self, *Locks::classlinker_classes_lock_);
8468 for (auto it = class_loaders_.begin(); it != class_loaders_.end(); ) {
8469 const ClassLoaderData& data = *it;
8470 // Need to use DecodeJObject so that we get null for cleared JNI weak globals.
8471 ObjPtr<mirror::ClassLoader> class_loader =
8472 ObjPtr<mirror::ClassLoader>::DownCast(self->DecodeJObject(data.weak_root));
8473 if (class_loader != nullptr) {
8476 VLOG(class_linker) << "Freeing class loader";
8477 to_delete.push_back(data);
8478 it = class_loaders_.erase(it);
8482 for (ClassLoaderData& data : to_delete) {
8483 DeleteClassLoader(self, data);
8487 class GetResolvedClassesVisitor : public ClassVisitor {
8489 GetResolvedClassesVisitor(std::set<DexCacheResolvedClasses>* result, bool ignore_boot_classes)
8491 ignore_boot_classes_(ignore_boot_classes),
8492 last_resolved_classes_(result->end()),
8493 last_dex_file_(nullptr),
8494 vlog_is_on_(VLOG_IS_ON(class_linker)),
8496 last_extra_stats_(extra_stats_.end()) { }
8498 bool operator()(ObjPtr<mirror::Class> klass) OVERRIDE REQUIRES_SHARED(Locks::mutator_lock_) {
8499 if (!klass->IsProxyClass() &&
8500 !klass->IsArrayClass() &&
8501 klass->IsResolved() &&
8502 !klass->IsErroneousResolved() &&
8503 (!ignore_boot_classes_ || klass->GetClassLoader() != nullptr)) {
8504 const DexFile& dex_file = klass->GetDexFile();
8505 if (&dex_file != last_dex_file_) {
8506 last_dex_file_ = &dex_file;
8507 DexCacheResolvedClasses resolved_classes(dex_file.GetLocation(),
8508 dex_file.GetBaseLocation(),
8509 dex_file.GetLocationChecksum());
8510 last_resolved_classes_ = result_->find(resolved_classes);
8511 if (last_resolved_classes_ == result_->end()) {
8512 last_resolved_classes_ = result_->insert(resolved_classes).first;
8515 bool added = last_resolved_classes_->AddClass(klass->GetDexTypeIndex());
8516 if (UNLIKELY(vlog_is_on_) && added) {
8517 const DexCacheResolvedClasses* resolved_classes = std::addressof(*last_resolved_classes_);
8518 if (last_extra_stats_ == extra_stats_.end() ||
8519 last_extra_stats_->first != resolved_classes) {
8520 last_extra_stats_ = extra_stats_.find(resolved_classes);
8521 if (last_extra_stats_ == extra_stats_.end()) {
8523 extra_stats_.emplace(resolved_classes, ExtraStats(dex_file.NumClassDefs())).first;
8531 void PrintStatistics() const {
8533 for (const DexCacheResolvedClasses& resolved_classes : *result_) {
8534 auto it = extra_stats_.find(std::addressof(resolved_classes));
8535 DCHECK(it != extra_stats_.end());
8536 const ExtraStats& extra_stats = it->second;
8537 LOG(INFO) << "Dex location " << resolved_classes.GetDexLocation()
8538 << " has " << resolved_classes.GetClasses().size() << " / "
8539 << extra_stats.number_of_class_defs_ << " resolved classes";
8546 explicit ExtraStats(uint32_t number_of_class_defs)
8547 : number_of_class_defs_(number_of_class_defs) {}
8548 uint32_t number_of_class_defs_;
8551 std::set<DexCacheResolvedClasses>* result_;
8552 bool ignore_boot_classes_;
8553 std::set<DexCacheResolvedClasses>::iterator last_resolved_classes_;
8554 const DexFile* last_dex_file_;
8558 std::map<const DexCacheResolvedClasses*, ExtraStats> extra_stats_;
8559 std::map<const DexCacheResolvedClasses*, ExtraStats>::iterator last_extra_stats_;
8562 std::set<DexCacheResolvedClasses> ClassLinker::GetResolvedClasses(bool ignore_boot_classes) {
8563 ScopedTrace trace(__PRETTY_FUNCTION__);
8564 ScopedObjectAccess soa(Thread::Current());
8565 ScopedAssertNoThreadSuspension ants(__FUNCTION__);
8566 std::set<DexCacheResolvedClasses> ret;
8567 VLOG(class_linker) << "Collecting resolved classes";
8568 const uint64_t start_time = NanoTime();
8569 GetResolvedClassesVisitor visitor(&ret, ignore_boot_classes);
8570 VisitClasses(&visitor);
8571 if (VLOG_IS_ON(class_linker)) {
8572 visitor.PrintStatistics();
8573 LOG(INFO) << "Collecting class profile took " << PrettyDuration(NanoTime() - start_time);
8578 std::unordered_set<std::string> ClassLinker::GetClassDescriptorsForProfileKeys(
8579 const std::set<DexCacheResolvedClasses>& classes) {
8580 ScopedTrace trace(__PRETTY_FUNCTION__);
8581 std::unordered_set<std::string> ret;
8582 Thread* const self = Thread::Current();
8583 std::unordered_map<std::string, const DexFile*> location_to_dex_file;
8584 ScopedObjectAccess soa(self);
8585 ScopedAssertNoThreadSuspension ants(__FUNCTION__);
8586 ReaderMutexLock mu(self, *Locks::dex_lock_);
8587 for (const ClassLinker::DexCacheData& data : GetDexCachesData()) {
8588 if (!self->IsJWeakCleared(data.weak_root)) {
8589 ObjPtr<mirror::DexCache> dex_cache = soa.Decode<mirror::DexCache>(data.weak_root);
8590 if (dex_cache != nullptr) {
8591 const DexFile* dex_file = dex_cache->GetDexFile();
8592 // There could be duplicates if two dex files with the same location are mapped.
8593 location_to_dex_file.emplace(
8594 ProfileCompilationInfo::GetProfileDexFileKey(dex_file->GetLocation()), dex_file);
8598 for (const DexCacheResolvedClasses& info : classes) {
8599 const std::string& profile_key = info.GetDexLocation();
8600 auto found = location_to_dex_file.find(profile_key);
8601 if (found != location_to_dex_file.end()) {
8602 const DexFile* dex_file = found->second;
8603 VLOG(profiler) << "Found opened dex file for " << dex_file->GetLocation() << " with "
8604 << info.GetClasses().size() << " classes";
8605 DCHECK_EQ(dex_file->GetLocationChecksum(), info.GetLocationChecksum());
8606 for (dex::TypeIndex type_idx : info.GetClasses()) {
8607 const DexFile::TypeId& type_id = dex_file->GetTypeId(type_idx);
8608 const char* descriptor = dex_file->GetTypeDescriptor(type_id);
8609 ret.insert(descriptor);
8612 VLOG(class_linker) << "Failed to find opened dex file for profile key " << profile_key;
8618 class ClassLinker::FindVirtualMethodHolderVisitor : public ClassVisitor {
8620 FindVirtualMethodHolderVisitor(const ArtMethod* method, PointerSize pointer_size)
8622 pointer_size_(pointer_size) {}
8624 bool operator()(ObjPtr<mirror::Class> klass) REQUIRES_SHARED(Locks::mutator_lock_) OVERRIDE {
8625 if (klass->GetVirtualMethodsSliceUnchecked(pointer_size_).Contains(method_)) {
8628 // Return false to stop searching if holder_ is not null.
8629 return holder_ == nullptr;
8632 ObjPtr<mirror::Class> holder_ = nullptr;
8633 const ArtMethod* const method_;
8634 const PointerSize pointer_size_;
8637 mirror::Class* ClassLinker::GetHoldingClassOfCopiedMethod(ArtMethod* method) {
8638 ScopedTrace trace(__FUNCTION__); // Since this function is slow, have a trace to notify people.
8639 CHECK(method->IsCopied());
8640 FindVirtualMethodHolderVisitor visitor(method, image_pointer_size_);
8641 VisitClasses(&visitor);
8642 return visitor.holder_.Ptr();
8645 // Instantiate ResolveMethod.
8646 template ArtMethod* ClassLinker::ResolveMethod<ClassLinker::kForceICCECheck>(
8647 const DexFile& dex_file,
8648 uint32_t method_idx,
8649 Handle<mirror::DexCache> dex_cache,
8650 Handle<mirror::ClassLoader> class_loader,
8651 ArtMethod* referrer,
8653 template ArtMethod* ClassLinker::ResolveMethod<ClassLinker::kNoICCECheckForCache>(
8654 const DexFile& dex_file,
8655 uint32_t method_idx,
8656 Handle<mirror::DexCache> dex_cache,
8657 Handle<mirror::ClassLoader> class_loader,
8658 ArtMethod* referrer,