1 /*
2  * Copyright (C) 2011 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "class.h"
18 
19 #include <unordered_set>
20 #include <string_view>
21 
22 #include "android-base/macros.h"
23 #include "android-base/stringprintf.h"
24 
25 #include "array-inl.h"
26 #include "art_field-inl.h"
27 #include "art_method-inl.h"
28 #include "base/enums.h"
29 #include "base/logging.h"  // For VLOG.
30 #include "base/utils.h"
31 #include "class-inl.h"
32 #include "class_ext-inl.h"
33 #include "class_linker-inl.h"
34 #include "class_loader.h"
35 #include "class_root-inl.h"
36 #include "dex/descriptors_names.h"
37 #include "dex/dex_file-inl.h"
38 #include "dex/dex_file_annotations.h"
39 #include "dex/signature-inl.h"
40 #include "dex_cache-inl.h"
41 #include "gc/accounting/card_table-inl.h"
42 #include "gc/heap-inl.h"
43 #include "handle_scope-inl.h"
44 #include "hidden_api.h"
45 #include "jni_id_type.h"
46 #include "subtype_check.h"
47 #include "method.h"
48 #include "object-inl.h"
49 #include "object-refvisitor-inl.h"
50 #include "object_array-inl.h"
51 #include "object_lock.h"
52 #include "string-inl.h"
53 #include "runtime.h"
54 #include "thread.h"
55 #include "throwable.h"
56 #include "well_known_classes.h"
57 
58 namespace art {
59 
60 // TODO: move to own CC file?
61 constexpr size_t BitString::kBitSizeAtPosition[BitString::kCapacity];
62 constexpr size_t BitString::kCapacity;
63 
64 namespace mirror {
65 
66 using android::base::StringPrintf;
67 
IsMirrored()68 bool Class::IsMirrored() {
69   if (LIKELY(!IsBootStrapClassLoaded())) {
70     return false;
71   }
72   if (IsPrimitive() || IsArrayClass() || IsProxyClass()) {
73     return true;
74   }
75   std::string name_storage;
76   const std::string_view name(this->GetDescriptor(&name_storage));
77   return IsMirroredDescriptor(name);
78 }
79 
GetPrimitiveClass(ObjPtr<mirror::String> name)80 ObjPtr<mirror::Class> Class::GetPrimitiveClass(ObjPtr<mirror::String> name) {
81   const char* expected_name = nullptr;
82   ClassRoot class_root = ClassRoot::kJavaLangObject;  // Invalid.
83   if (name != nullptr && name->GetLength() >= 2) {
84     // Perfect hash for the expected values: from the second letters of the primitive types,
85     // only 'y' has the bit 0x10 set, so use it to change 'b' to 'B'.
86     char hash = name->CharAt(0) ^ ((name->CharAt(1) & 0x10) << 1);
87     switch (hash) {
88       case 'b': expected_name = "boolean"; class_root = ClassRoot::kPrimitiveBoolean; break;
89       case 'B': expected_name = "byte";    class_root = ClassRoot::kPrimitiveByte;    break;
90       case 'c': expected_name = "char";    class_root = ClassRoot::kPrimitiveChar;    break;
91       case 'd': expected_name = "double";  class_root = ClassRoot::kPrimitiveDouble;  break;
92       case 'f': expected_name = "float";   class_root = ClassRoot::kPrimitiveFloat;   break;
93       case 'i': expected_name = "int";     class_root = ClassRoot::kPrimitiveInt;     break;
94       case 'l': expected_name = "long";    class_root = ClassRoot::kPrimitiveLong;    break;
95       case 's': expected_name = "short";   class_root = ClassRoot::kPrimitiveShort;   break;
96       case 'v': expected_name = "void";    class_root = ClassRoot::kPrimitiveVoid;    break;
97       default: break;
98     }
99   }
100   if (expected_name != nullptr && name->Equals(expected_name)) {
101     ObjPtr<mirror::Class> klass = GetClassRoot(class_root);
102     DCHECK(klass != nullptr);
103     return klass;
104   } else {
105     Thread* self = Thread::Current();
106     if (name == nullptr) {
107       // Note: ThrowNullPointerException() requires a message which we deliberately want to omit.
108       self->ThrowNewException("Ljava/lang/NullPointerException;", /* msg= */ nullptr);
109     } else {
110       self->ThrowNewException("Ljava/lang/ClassNotFoundException;", name->ToModifiedUtf8().c_str());
111     }
112     return nullptr;
113   }
114 }
115 
EnsureExtDataPresent(Handle<Class> h_this,Thread * self)116 ObjPtr<ClassExt> Class::EnsureExtDataPresent(Handle<Class> h_this, Thread* self) {
117   ObjPtr<ClassExt> existing(h_this->GetExtData());
118   if (!existing.IsNull()) {
119     return existing;
120   }
121   StackHandleScope<2> hs(self);
122   // Clear exception so we can allocate.
123   Handle<Throwable> throwable(hs.NewHandle(self->GetException()));
124   self->ClearException();
125   // Allocate the ClassExt
126   Handle<ClassExt> new_ext(hs.NewHandle(ClassExt::Alloc(self)));
127   if (new_ext == nullptr) {
128     // OOM allocating the classExt.
129     // TODO Should we restore the suppressed exception?
130     self->AssertPendingOOMException();
131     return nullptr;
132   } else {
133     MemberOffset ext_offset(OFFSET_OF_OBJECT_MEMBER(Class, ext_data_));
134     bool set;
135     // Set the ext_data_ field using CAS semantics.
136     if (Runtime::Current()->IsActiveTransaction()) {
137       set = h_this->CasFieldObject<true>(ext_offset,
138                                          nullptr,
139                                          new_ext.Get(),
140                                          CASMode::kStrong,
141                                          std::memory_order_seq_cst);
142     } else {
143       set = h_this->CasFieldObject<false>(ext_offset,
144                                           nullptr,
145                                           new_ext.Get(),
146                                           CASMode::kStrong,
147                                           std::memory_order_seq_cst);
148     }
149     ObjPtr<ClassExt> ret(set ? new_ext.Get() : h_this->GetExtData());
150     DCHECK(!set || h_this->GetExtData() == new_ext.Get());
151     CHECK(!ret.IsNull());
152     // Restore the exception if there was one.
153     if (throwable != nullptr) {
154       self->SetException(throwable.Get());
155     }
156     return ret;
157   }
158 }
159 
160 template <typename T>
CheckSetStatus(Thread * self,T thiz,ClassStatus new_status,ClassStatus old_status)161 static void CheckSetStatus(Thread* self, T thiz, ClassStatus new_status, ClassStatus old_status)
162     REQUIRES_SHARED(Locks::mutator_lock_) {
163   if (UNLIKELY(new_status <= old_status && new_status != ClassStatus::kErrorUnresolved &&
164                new_status != ClassStatus::kErrorResolved && new_status != ClassStatus::kRetired)) {
165     LOG(FATAL) << "Unexpected change back of class status for " << thiz->PrettyClass() << " "
166                << old_status << " -> " << new_status;
167   }
168   if (old_status == ClassStatus::kInitialized) {
169     // We do not hold the lock for making the class visibly initialized
170     // as this is unnecessary and could lead to deadlocks.
171     CHECK_EQ(new_status, ClassStatus::kVisiblyInitialized);
172   } else if ((new_status >= ClassStatus::kResolved || old_status >= ClassStatus::kResolved) &&
173              !Locks::mutator_lock_->IsExclusiveHeld(self)) {
174     // When classes are being resolved the resolution code should hold the
175     // lock or have everything else suspended
176     CHECK_EQ(thiz->GetLockOwnerThreadId(), self->GetThreadId())
177         << "Attempt to change status of class while not holding its lock: " << thiz->PrettyClass()
178         << " " << old_status << " -> " << new_status;
179   }
180   if (UNLIKELY(Locks::mutator_lock_->IsExclusiveHeld(self))) {
181     CHECK(!Class::IsErroneous(new_status))
182         << "status " << new_status
183         << " cannot be set while suspend-all is active. Would require allocations.";
184     CHECK(thiz->IsResolved())
185         << thiz->PrettyClass()
186         << " not resolved during suspend-all status change. Waiters might be missed!";
187   }
188 }
189 
SetStatusInternal(ClassStatus new_status)190 void Class::SetStatusInternal(ClassStatus new_status) {
191   if (kBitstringSubtypeCheckEnabled) {
192     // FIXME: This looks broken with respect to aborted transactions.
193     SubtypeCheck<ObjPtr<mirror::Class>>::WriteStatus(this, new_status);
194   } else {
195     // The ClassStatus is always in the 4 most-significant bits of status_.
196     static_assert(sizeof(status_) == sizeof(uint32_t), "Size of status_ not equal to uint32");
197     uint32_t new_status_value = static_cast<uint32_t>(new_status) << (32 - kClassStatusBitSize);
198     if (Runtime::Current()->IsActiveTransaction()) {
199       SetField32Volatile<true>(StatusOffset(), new_status_value);
200     } else {
201       SetField32Volatile<false>(StatusOffset(), new_status_value);
202     }
203   }
204 }
205 
SetStatusLocked(ClassStatus new_status)206 void Class::SetStatusLocked(ClassStatus new_status) {
207   ClassStatus old_status = GetStatus();
208   CheckSetStatus(Thread::Current(), this, new_status, old_status);
209   SetStatusInternal(new_status);
210 }
211 
SetStatus(Handle<Class> h_this,ClassStatus new_status,Thread * self)212 void Class::SetStatus(Handle<Class> h_this, ClassStatus new_status, Thread* self) {
213   ClassStatus old_status = h_this->GetStatus();
214   ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
215   bool class_linker_initialized = class_linker != nullptr && class_linker->IsInitialized();
216   if (LIKELY(class_linker_initialized)) {
217     CheckSetStatus(self, h_this, new_status, old_status);
218   }
219   if (UNLIKELY(IsErroneous(new_status))) {
220     CHECK(!h_this->IsErroneous())
221         << "Attempt to set as erroneous an already erroneous class "
222         << h_this->PrettyClass()
223         << " old_status: " << old_status << " new_status: " << new_status;
224     CHECK_EQ(new_status == ClassStatus::kErrorResolved, old_status >= ClassStatus::kResolved);
225     if (VLOG_IS_ON(class_linker)) {
226       LOG(ERROR) << "Setting " << h_this->PrettyDescriptor() << " to erroneous.";
227       if (self->IsExceptionPending()) {
228         LOG(ERROR) << "Exception: " << self->GetException()->Dump();
229       }
230     }
231 
232     ObjPtr<ClassExt> ext(EnsureExtDataPresent(h_this, self));
233     if (!ext.IsNull()) {
234       self->AssertPendingException();
235       ext->SetVerifyError(self->GetException());
236     } else {
237       self->AssertPendingOOMException();
238     }
239     self->AssertPendingException();
240   }
241 
242   h_this->SetStatusInternal(new_status);
243 
244   // Setting the object size alloc fast path needs to be after the status write so that if the
245   // alloc path sees a valid object size, we would know that it's initialized as long as it has a
246   // load-acquire/fake dependency.
247   if (new_status == ClassStatus::kVisiblyInitialized && !h_this->IsVariableSize()) {
248     DCHECK_EQ(h_this->GetObjectSizeAllocFastPath(), std::numeric_limits<uint32_t>::max());
249     // Finalizable objects must always go slow path.
250     if (!h_this->IsFinalizable()) {
251       h_this->SetObjectSizeAllocFastPath(RoundUp(h_this->GetObjectSize(), kObjectAlignment));
252     }
253   }
254 
255   if (kIsDebugBuild && new_status >= ClassStatus::kInitialized) {
256     CHECK(h_this->WasVerificationAttempted()) << h_this->PrettyClassAndClassLoader();
257   }
258 
259   if (!class_linker_initialized) {
260     // When the class linker is being initialized its single threaded and by definition there can be
261     // no waiters. During initialization classes may appear temporary but won't be retired as their
262     // size was statically computed.
263   } else {
264     // Classes that are being resolved or initialized need to notify waiters that the class status
265     // changed. See ClassLinker::EnsureResolved and ClassLinker::WaitForInitializeClass.
266     if (h_this->IsTemp()) {
267       // Class is a temporary one, ensure that waiters for resolution get notified of retirement
268       // so that they can grab the new version of the class from the class linker's table.
269       CHECK_LT(new_status, ClassStatus::kResolved) << h_this->PrettyDescriptor();
270       if (new_status == ClassStatus::kRetired || new_status == ClassStatus::kErrorUnresolved) {
271         h_this->NotifyAll(self);
272       }
273     } else if (old_status == ClassStatus::kInitialized) {
274       // Do not notify for transition from kInitialized to ClassStatus::kVisiblyInitialized.
275       // This is a hidden transition, not observable by bytecode.
276       DCHECK_EQ(new_status, ClassStatus::kVisiblyInitialized);  // Already CHECK()ed above.
277     } else {
278       CHECK_NE(new_status, ClassStatus::kRetired);
279       if (old_status >= ClassStatus::kResolved || new_status >= ClassStatus::kResolved) {
280         h_this->NotifyAll(self);
281       }
282     }
283   }
284 }
285 
SetStatusForPrimitiveOrArray(ClassStatus new_status)286 void Class::SetStatusForPrimitiveOrArray(ClassStatus new_status) {
287   DCHECK(IsPrimitive<kVerifyNone>() || IsArrayClass<kVerifyNone>());
288   DCHECK(!IsErroneous(new_status));
289   DCHECK(!IsErroneous(GetStatus<kVerifyNone>()));
290   DCHECK_GT(new_status, GetStatus<kVerifyNone>());
291 
292   if (kBitstringSubtypeCheckEnabled) {
293     LOG(FATAL) << "Unimplemented";
294   }
295   // The ClassStatus is always in the 4 most-significant bits of status_.
296   static_assert(sizeof(status_) == sizeof(uint32_t), "Size of status_ not equal to uint32");
297   uint32_t new_status_value = static_cast<uint32_t>(new_status) << (32 - kClassStatusBitSize);
298   // Use normal store. For primitives and core arrays classes (Object[],
299   // Class[], String[] and primitive arrays), the status is set while the
300   // process is still single threaded. For other arrays classes, it is set
301   // in a pre-fence visitor which initializes all fields and the subsequent
302   // fence together with address dependency shall ensure memory visibility.
303   SetField32</*kTransactionActive=*/ false,
304              /*kCheckTransaction=*/ false,
305              kVerifyNone>(StatusOffset(), new_status_value);
306 
307   // Do not update `object_alloc_fast_path_`. Arrays are variable size and
308   // instances of primitive classes cannot be created at all.
309 
310   if (kIsDebugBuild && new_status >= ClassStatus::kInitialized) {
311     CHECK(WasVerificationAttempted()) << PrettyClassAndClassLoader();
312   }
313 
314   // There can be no waiters to notify as these classes are initialized
315   // before another thread can see them.
316 }
317 
SetDexCache(ObjPtr<DexCache> new_dex_cache)318 void Class::SetDexCache(ObjPtr<DexCache> new_dex_cache) {
319   SetFieldObjectTransaction(OFFSET_OF_OBJECT_MEMBER(Class, dex_cache_), new_dex_cache);
320 }
321 
SetClassSize(uint32_t new_class_size)322 void Class::SetClassSize(uint32_t new_class_size) {
323   if (kIsDebugBuild && new_class_size < GetClassSize()) {
324     DumpClass(LOG_STREAM(FATAL_WITHOUT_ABORT), kDumpClassFullDetail);
325     LOG(FATAL_WITHOUT_ABORT) << new_class_size << " vs " << GetClassSize();
326     LOG(FATAL) << "class=" << PrettyTypeOf();
327   }
328   SetField32</*kTransactionActive=*/ false, /*kCheckTransaction=*/ false>(
329       OFFSET_OF_OBJECT_MEMBER(Class, class_size_), new_class_size);
330 }
331 
GetObsoleteClass()332 ObjPtr<Class> Class::GetObsoleteClass() {
333   ObjPtr<ClassExt> ext(GetExtData());
334   if (ext.IsNull()) {
335     return nullptr;
336   } else {
337     return ext->GetObsoleteClass();
338   }
339 }
340 
341 // Return the class' name. The exact format is bizarre, but it's the specified behavior for
342 // Class.getName: keywords for primitive types, regular "[I" form for primitive arrays (so "int"
343 // but "[I"), and arrays of reference types written between "L" and ";" but with dots rather than
344 // slashes (so "java.lang.String" but "[Ljava.lang.String;"). Madness.
ComputeName(Handle<Class> h_this)345 ObjPtr<String> Class::ComputeName(Handle<Class> h_this) {
346   ObjPtr<String> name = h_this->GetName();
347   if (name != nullptr) {
348     return name;
349   }
350   std::string temp;
351   const char* descriptor = h_this->GetDescriptor(&temp);
352   Thread* self = Thread::Current();
353   if ((descriptor[0] != 'L') && (descriptor[0] != '[')) {
354     // The descriptor indicates that this is the class for
355     // a primitive type; special-case the return value.
356     const char* c_name = nullptr;
357     switch (descriptor[0]) {
358     case 'Z': c_name = "boolean"; break;
359     case 'B': c_name = "byte";    break;
360     case 'C': c_name = "char";    break;
361     case 'S': c_name = "short";   break;
362     case 'I': c_name = "int";     break;
363     case 'J': c_name = "long";    break;
364     case 'F': c_name = "float";   break;
365     case 'D': c_name = "double";  break;
366     case 'V': c_name = "void";    break;
367     default:
368       LOG(FATAL) << "Unknown primitive type: " << PrintableChar(descriptor[0]);
369     }
370     name = String::AllocFromModifiedUtf8(self, c_name);
371   } else {
372     // Convert the UTF-8 name to a java.lang.String. The name must use '.' to separate package
373     // components.
374     name = String::AllocFromModifiedUtf8(self, DescriptorToDot(descriptor).c_str());
375   }
376   h_this->SetName(name);
377   return name;
378 }
379 
DumpClass(std::ostream & os,int flags)380 void Class::DumpClass(std::ostream& os, int flags) {
381   if ((flags & kDumpClassFullDetail) == 0) {
382     os << PrettyClass();
383     if ((flags & kDumpClassClassLoader) != 0) {
384       os << ' ' << GetClassLoader();
385     }
386     if ((flags & kDumpClassInitialized) != 0) {
387       os << ' ' << GetStatus();
388     }
389     os << "\n";
390     return;
391   }
392 
393   Thread* const self = Thread::Current();
394   StackHandleScope<2> hs(self);
395   Handle<Class> h_this(hs.NewHandle(this));
396   Handle<Class> h_super(hs.NewHandle(GetSuperClass()));
397   auto image_pointer_size = Runtime::Current()->GetClassLinker()->GetImagePointerSize();
398 
399   std::string temp;
400   os << "----- " << (IsInterface() ? "interface" : "class") << " "
401      << "'" << GetDescriptor(&temp) << "' cl=" << GetClassLoader() << " -----\n",
402   os << "  objectSize=" << SizeOf() << " "
403      << "(" << (h_super != nullptr ? h_super->SizeOf() : -1) << " from super)\n",
404   os << StringPrintf("  access=0x%04x.%04x\n",
405       GetAccessFlags() >> 16, GetAccessFlags() & kAccJavaFlagsMask);
406   if (h_super != nullptr) {
407     os << "  super='" << h_super->PrettyClass() << "' (cl=" << h_super->GetClassLoader()
408        << ")\n";
409   }
410   if (IsArrayClass()) {
411     os << "  componentType=" << PrettyClass(GetComponentType()) << "\n";
412   }
413   const size_t num_direct_interfaces = NumDirectInterfaces();
414   if (num_direct_interfaces > 0) {
415     os << "  interfaces (" << num_direct_interfaces << "):\n";
416     for (size_t i = 0; i < num_direct_interfaces; ++i) {
417       ObjPtr<Class> interface = GetDirectInterface(self, h_this.Get(), i);
418       if (interface == nullptr) {
419         os << StringPrintf("    %2zd: nullptr!\n", i);
420       } else {
421         ObjPtr<ClassLoader> cl = interface->GetClassLoader();
422         os << StringPrintf("    %2zd: %s (cl=%p)\n", i, PrettyClass(interface).c_str(), cl.Ptr());
423       }
424     }
425   }
426   if (!IsLoaded()) {
427     os << "  class not yet loaded";
428   } else {
429     // After this point, this may have moved due to GetDirectInterface.
430     os << "  vtable (" << h_this->NumVirtualMethods() << " entries, "
431         << (h_super != nullptr ? h_super->NumVirtualMethods() : 0) << " in super):\n";
432     for (size_t i = 0; i < NumVirtualMethods(); ++i) {
433       os << StringPrintf("    %2zd: %s\n", i, ArtMethod::PrettyMethod(
434           h_this->GetVirtualMethodDuringLinking(i, image_pointer_size)).c_str());
435     }
436     os << "  direct methods (" << h_this->NumDirectMethods() << " entries):\n";
437     for (size_t i = 0; i < h_this->NumDirectMethods(); ++i) {
438       os << StringPrintf("    %2zd: %s\n", i, ArtMethod::PrettyMethod(
439           h_this->GetDirectMethod(i, image_pointer_size)).c_str());
440     }
441     if (h_this->NumStaticFields() > 0) {
442       os << "  static fields (" << h_this->NumStaticFields() << " entries):\n";
443       if (h_this->IsResolved()) {
444         for (size_t i = 0; i < h_this->NumStaticFields(); ++i) {
445           os << StringPrintf("    %2zd: %s\n", i,
446                              ArtField::PrettyField(h_this->GetStaticField(i)).c_str());
447         }
448       } else {
449         os << "    <not yet available>";
450       }
451     }
452     if (h_this->NumInstanceFields() > 0) {
453       os << "  instance fields (" << h_this->NumInstanceFields() << " entries):\n";
454       if (h_this->IsResolved()) {
455         for (size_t i = 0; i < h_this->NumInstanceFields(); ++i) {
456           os << StringPrintf("    %2zd: %s\n", i,
457                              ArtField::PrettyField(h_this->GetInstanceField(i)).c_str());
458         }
459       } else {
460         os << "    <not yet available>";
461       }
462     }
463   }
464 }
465 
SetReferenceInstanceOffsets(uint32_t new_reference_offsets)466 void Class::SetReferenceInstanceOffsets(uint32_t new_reference_offsets) {
467   if (kIsDebugBuild && new_reference_offsets != kClassWalkSuper) {
468     // Check that the number of bits set in the reference offset bitmap
469     // agrees with the number of references.
470     uint32_t count = 0;
471     for (ObjPtr<Class> c = this; c != nullptr; c = c->GetSuperClass()) {
472       count += c->NumReferenceInstanceFieldsDuringLinking();
473     }
474     // +1 for the Class in Object.
475     CHECK_EQ(static_cast<uint32_t>(POPCOUNT(new_reference_offsets)) + 1, count);
476   }
477   // Not called within a transaction.
478   SetField32<false>(OFFSET_OF_OBJECT_MEMBER(Class, reference_instance_offsets_),
479                     new_reference_offsets);
480 }
481 
IsInSamePackage(std::string_view descriptor1,std::string_view descriptor2)482 bool Class::IsInSamePackage(std::string_view descriptor1, std::string_view descriptor2) {
483   size_t i = 0;
484   size_t min_length = std::min(descriptor1.size(), descriptor2.size());
485   while (i < min_length && descriptor1[i] == descriptor2[i]) {
486     ++i;
487   }
488   if (descriptor1.find('/', i) != std::string_view::npos ||
489       descriptor2.find('/', i) != std::string_view::npos) {
490     return false;
491   } else {
492     return true;
493   }
494 }
495 
IsInSamePackage(ObjPtr<Class> that)496 bool Class::IsInSamePackage(ObjPtr<Class> that) {
497   ObjPtr<Class> klass1 = this;
498   ObjPtr<Class> klass2 = that;
499   if (klass1 == klass2) {
500     return true;
501   }
502   // Class loaders must match.
503   if (klass1->GetClassLoader() != klass2->GetClassLoader()) {
504     return false;
505   }
506   // Arrays are in the same package when their element classes are.
507   while (klass1->IsArrayClass()) {
508     klass1 = klass1->GetComponentType();
509   }
510   while (klass2->IsArrayClass()) {
511     klass2 = klass2->GetComponentType();
512   }
513   // trivial check again for array types
514   if (klass1 == klass2) {
515     return true;
516   }
517   // Compare the package part of the descriptor string.
518   std::string temp1, temp2;
519   return IsInSamePackage(klass1->GetDescriptor(&temp1), klass2->GetDescriptor(&temp2));
520 }
521 
IsThrowableClass()522 bool Class::IsThrowableClass() {
523   return GetClassRoot<mirror::Throwable>()->IsAssignableFrom(this);
524 }
525 
526 template <typename SignatureType>
FindInterfaceMethodWithSignature(ObjPtr<Class> klass,std::string_view name,const SignatureType & signature,PointerSize pointer_size)527 static inline ArtMethod* FindInterfaceMethodWithSignature(ObjPtr<Class> klass,
528                                                           std::string_view name,
529                                                           const SignatureType& signature,
530                                                           PointerSize pointer_size)
531     REQUIRES_SHARED(Locks::mutator_lock_) {
532   // If the current class is not an interface, skip the search of its declared methods;
533   // such lookup is used only to distinguish between IncompatibleClassChangeError and
534   // NoSuchMethodError and the caller has already tried to search methods in the class.
535   if (LIKELY(klass->IsInterface())) {
536     // Search declared methods, both direct and virtual.
537     // (This lookup is used also for invoke-static on interface classes.)
538     for (ArtMethod& method : klass->GetDeclaredMethodsSlice(pointer_size)) {
539       if (method.GetNameView() == name && method.GetSignature() == signature) {
540         return &method;
541       }
542     }
543   }
544 
545   // TODO: If there is a unique maximally-specific non-abstract superinterface method,
546   // we should return it, otherwise an arbitrary one can be returned.
547   ObjPtr<IfTable> iftable = klass->GetIfTable();
548   for (int32_t i = 0, iftable_count = iftable->Count(); i < iftable_count; ++i) {
549     ObjPtr<Class> iface = iftable->GetInterface(i);
550     for (ArtMethod& method : iface->GetVirtualMethodsSlice(pointer_size)) {
551       if (method.GetNameView() == name && method.GetSignature() == signature) {
552         return &method;
553       }
554     }
555   }
556 
557   // Then search for public non-static methods in the java.lang.Object.
558   if (LIKELY(klass->IsInterface())) {
559     ObjPtr<Class> object_class = klass->GetSuperClass();
560     DCHECK(object_class->IsObjectClass());
561     for (ArtMethod& method : object_class->GetDeclaredMethodsSlice(pointer_size)) {
562       if (method.IsPublic() && !method.IsStatic() &&
563           method.GetNameView() == name && method.GetSignature() == signature) {
564         return &method;
565       }
566     }
567   }
568   return nullptr;
569 }
570 
FindInterfaceMethod(std::string_view name,std::string_view signature,PointerSize pointer_size)571 ArtMethod* Class::FindInterfaceMethod(std::string_view name,
572                                       std::string_view signature,
573                                       PointerSize pointer_size) {
574   return FindInterfaceMethodWithSignature(this, name, signature, pointer_size);
575 }
576 
FindInterfaceMethod(std::string_view name,const Signature & signature,PointerSize pointer_size)577 ArtMethod* Class::FindInterfaceMethod(std::string_view name,
578                                       const Signature& signature,
579                                       PointerSize pointer_size) {
580   return FindInterfaceMethodWithSignature(this, name, signature, pointer_size);
581 }
582 
FindInterfaceMethod(ObjPtr<DexCache> dex_cache,uint32_t dex_method_idx,PointerSize pointer_size)583 ArtMethod* Class::FindInterfaceMethod(ObjPtr<DexCache> dex_cache,
584                                       uint32_t dex_method_idx,
585                                       PointerSize pointer_size) {
586   // We always search by name and signature, ignoring the type index in the MethodId.
587   const DexFile& dex_file = *dex_cache->GetDexFile();
588   const dex::MethodId& method_id = dex_file.GetMethodId(dex_method_idx);
589   std::string_view name = dex_file.StringViewByIdx(method_id.name_idx_);
590   const Signature signature = dex_file.GetMethodSignature(method_id);
591   return FindInterfaceMethod(name, signature, pointer_size);
592 }
593 
IsValidInheritanceCheck(ObjPtr<mirror::Class> klass,ObjPtr<mirror::Class> declaring_class)594 static inline bool IsValidInheritanceCheck(ObjPtr<mirror::Class> klass,
595                                            ObjPtr<mirror::Class> declaring_class)
596     REQUIRES_SHARED(Locks::mutator_lock_) {
597   if (klass->IsArrayClass()) {
598     return declaring_class->IsObjectClass();
599   } else if (klass->IsInterface()) {
600     return declaring_class->IsObjectClass() || declaring_class == klass;
601   } else {
602     return klass->IsSubClass(declaring_class);
603   }
604 }
605 
IsInheritedMethod(ObjPtr<mirror::Class> klass,ObjPtr<mirror::Class> declaring_class,ArtMethod & method)606 static inline bool IsInheritedMethod(ObjPtr<mirror::Class> klass,
607                                      ObjPtr<mirror::Class> declaring_class,
608                                      ArtMethod& method)
609     REQUIRES_SHARED(Locks::mutator_lock_) {
610   DCHECK_EQ(declaring_class, method.GetDeclaringClass());
611   DCHECK_NE(klass, declaring_class);
612   DCHECK(IsValidInheritanceCheck(klass, declaring_class));
613   uint32_t access_flags = method.GetAccessFlags();
614   if ((access_flags & (kAccPublic | kAccProtected)) != 0) {
615     return true;
616   }
617   if ((access_flags & kAccPrivate) != 0) {
618     return false;
619   }
620   for (; klass != declaring_class; klass = klass->GetSuperClass()) {
621     if (!klass->IsInSamePackage(declaring_class)) {
622       return false;
623     }
624   }
625   return true;
626 }
627 
628 template <typename SignatureType>
FindClassMethodWithSignature(ObjPtr<Class> this_klass,std::string_view name,const SignatureType & signature,PointerSize pointer_size)629 static inline ArtMethod* FindClassMethodWithSignature(ObjPtr<Class> this_klass,
630                                                       std::string_view name,
631                                                       const SignatureType& signature,
632                                                       PointerSize pointer_size)
633     REQUIRES_SHARED(Locks::mutator_lock_) {
634   // Search declared methods first.
635   for (ArtMethod& method : this_klass->GetDeclaredMethodsSlice(pointer_size)) {
636     ArtMethod* np_method = method.GetInterfaceMethodIfProxy(pointer_size);
637     if (np_method->GetName() == name && np_method->GetSignature() == signature) {
638       return &method;
639     }
640   }
641 
642   // Then search the superclass chain. If we find an inherited method, return it.
643   // If we find a method that's not inherited because of access restrictions,
644   // try to find a method inherited from an interface in copied methods.
645   ObjPtr<Class> klass = this_klass->GetSuperClass();
646   ArtMethod* uninherited_method = nullptr;
647   for (; klass != nullptr; klass = klass->GetSuperClass()) {
648     DCHECK(!klass->IsProxyClass());
649     for (ArtMethod& method : klass->GetDeclaredMethodsSlice(pointer_size)) {
650       if (method.GetName() == name && method.GetSignature() == signature) {
651         if (IsInheritedMethod(this_klass, klass, method)) {
652           return &method;
653         }
654         uninherited_method = &method;
655         break;
656       }
657     }
658     if (uninherited_method != nullptr) {
659       break;
660     }
661   }
662 
663   // Then search copied methods.
664   // If we found a method that's not inherited, stop the search in its declaring class.
665   ObjPtr<Class> end_klass = klass;
666   DCHECK_EQ(uninherited_method != nullptr, end_klass != nullptr);
667   klass = this_klass;
668   if (UNLIKELY(klass->IsProxyClass())) {
669     DCHECK(klass->GetCopiedMethodsSlice(pointer_size).empty());
670     klass = klass->GetSuperClass();
671   }
672   for (; klass != end_klass; klass = klass->GetSuperClass()) {
673     DCHECK(!klass->IsProxyClass());
674     for (ArtMethod& method : klass->GetCopiedMethodsSlice(pointer_size)) {
675       if (method.GetName() == name && method.GetSignature() == signature) {
676         return &method;  // No further check needed, copied methods are inherited by definition.
677       }
678     }
679   }
680   return uninherited_method;  // Return the `uninherited_method` if any.
681 }
682 
683 
FindClassMethod(std::string_view name,std::string_view signature,PointerSize pointer_size)684 ArtMethod* Class::FindClassMethod(std::string_view name,
685                                   std::string_view signature,
686                                   PointerSize pointer_size) {
687   return FindClassMethodWithSignature(this, name, signature, pointer_size);
688 }
689 
FindClassMethod(std::string_view name,const Signature & signature,PointerSize pointer_size)690 ArtMethod* Class::FindClassMethod(std::string_view name,
691                                   const Signature& signature,
692                                   PointerSize pointer_size) {
693   return FindClassMethodWithSignature(this, name, signature, pointer_size);
694 }
695 
FindClassMethod(ObjPtr<DexCache> dex_cache,uint32_t dex_method_idx,PointerSize pointer_size)696 ArtMethod* Class::FindClassMethod(ObjPtr<DexCache> dex_cache,
697                                   uint32_t dex_method_idx,
698                                   PointerSize pointer_size) {
699   // FIXME: Hijacking a proxy class by a custom class loader can break this assumption.
700   DCHECK(!IsProxyClass());
701 
702   // First try to find a declared method by dex_method_idx if we have a dex_cache match.
703   ObjPtr<DexCache> this_dex_cache = GetDexCache();
704   if (this_dex_cache == dex_cache) {
705     // Lookup is always performed in the class referenced by the MethodId.
706     DCHECK_EQ(dex_type_idx_, GetDexFile().GetMethodId(dex_method_idx).class_idx_.index_);
707     for (ArtMethod& method : GetDeclaredMethodsSlice(pointer_size)) {
708       if (method.GetDexMethodIndex() == dex_method_idx) {
709         return &method;
710       }
711     }
712   }
713   // If not found, we need to search by name and signature.
714   const DexFile& dex_file = *dex_cache->GetDexFile();
715   const dex::MethodId& method_id = dex_file.GetMethodId(dex_method_idx);
716   const Signature signature = dex_file.GetMethodSignature(method_id);
717   std::string_view name;  // Delay strlen() until actually needed.
718   // If we do not have a dex_cache match, try to find the declared method in this class now.
719   if (this_dex_cache != dex_cache && !GetDeclaredMethodsSlice(pointer_size).empty()) {
720     DCHECK(name.empty());
721     // Avoid string comparisons by comparing the respective unicode lengths first.
722     uint32_t length, other_length;  // UTF16 length.
723     name = dex_file.GetMethodName(method_id, &length);
724     for (ArtMethod& method : GetDeclaredMethodsSlice(pointer_size)) {
725       DCHECK_NE(method.GetDexMethodIndex(), dex::kDexNoIndex);
726       const char* other_name = method.GetDexFile()->GetMethodName(
727           method.GetDexMethodIndex(), &other_length);
728       if (length == other_length && name == other_name && signature == method.GetSignature()) {
729         return &method;
730       }
731     }
732   }
733 
734   // Then search the superclass chain. If we find an inherited method, return it.
735   // If we find a method that's not inherited because of access restrictions,
736   // try to find a method inherited from an interface in copied methods.
737   ArtMethod* uninherited_method = nullptr;
738   ObjPtr<Class> klass = GetSuperClass();
739   for (; klass != nullptr; klass = klass->GetSuperClass()) {
740     ArtMethod* candidate_method = nullptr;
741     ArraySlice<ArtMethod> declared_methods = klass->GetDeclaredMethodsSlice(pointer_size);
742     if (klass->GetDexCache() == dex_cache) {
743       // Matching dex_cache. We cannot compare the `dex_method_idx` anymore because
744       // the type index differs, so compare the name index and proto index.
745       for (ArtMethod& method : declared_methods) {
746         const dex::MethodId& cmp_method_id = dex_file.GetMethodId(method.GetDexMethodIndex());
747         if (cmp_method_id.name_idx_ == method_id.name_idx_ &&
748             cmp_method_id.proto_idx_ == method_id.proto_idx_) {
749           candidate_method = &method;
750           break;
751         }
752       }
753     } else {
754       if (!declared_methods.empty() && name.empty()) {
755         name = dex_file.StringDataByIdx(method_id.name_idx_);
756       }
757       for (ArtMethod& method : declared_methods) {
758         if (method.GetName() == name && method.GetSignature() == signature) {
759           candidate_method = &method;
760           break;
761         }
762       }
763     }
764     if (candidate_method != nullptr) {
765       if (IsInheritedMethod(this, klass, *candidate_method)) {
766         return candidate_method;
767       } else {
768         uninherited_method = candidate_method;
769         break;
770       }
771     }
772   }
773 
774   // Then search copied methods.
775   // If we found a method that's not inherited, stop the search in its declaring class.
776   ObjPtr<Class> end_klass = klass;
777   DCHECK_EQ(uninherited_method != nullptr, end_klass != nullptr);
778   // After we have searched the declared methods of the super-class chain,
779   // search copied methods which can contain methods from interfaces.
780   for (klass = this; klass != end_klass; klass = klass->GetSuperClass()) {
781     ArraySlice<ArtMethod> copied_methods = klass->GetCopiedMethodsSlice(pointer_size);
782     if (!copied_methods.empty() && name.empty()) {
783       name = dex_file.StringDataByIdx(method_id.name_idx_);
784     }
785     for (ArtMethod& method : copied_methods) {
786       if (method.GetName() == name && method.GetSignature() == signature) {
787         return &method;  // No further check needed, copied methods are inherited by definition.
788       }
789     }
790   }
791   return uninherited_method;  // Return the `uninherited_method` if any.
792 }
793 
FindConstructor(std::string_view signature,PointerSize pointer_size)794 ArtMethod* Class::FindConstructor(std::string_view signature, PointerSize pointer_size) {
795   // Internal helper, never called on proxy classes. We can skip GetInterfaceMethodIfProxy().
796   DCHECK(!IsProxyClass());
797   std::string_view name("<init>");
798   for (ArtMethod& method : GetDirectMethodsSliceUnchecked(pointer_size)) {
799     if (method.GetName() == name && method.GetSignature() == signature) {
800       return &method;
801     }
802   }
803   return nullptr;
804 }
805 
FindDeclaredDirectMethodByName(std::string_view name,PointerSize pointer_size)806 ArtMethod* Class::FindDeclaredDirectMethodByName(std::string_view name, PointerSize pointer_size) {
807   for (auto& method : GetDirectMethods(pointer_size)) {
808     ArtMethod* const np_method = method.GetInterfaceMethodIfProxy(pointer_size);
809     if (name == np_method->GetName()) {
810       return &method;
811     }
812   }
813   return nullptr;
814 }
815 
FindDeclaredVirtualMethodByName(std::string_view name,PointerSize pointer_size)816 ArtMethod* Class::FindDeclaredVirtualMethodByName(std::string_view name, PointerSize pointer_size) {
817   for (auto& method : GetVirtualMethods(pointer_size)) {
818     ArtMethod* const np_method = method.GetInterfaceMethodIfProxy(pointer_size);
819     if (name == np_method->GetName()) {
820       return &method;
821     }
822   }
823   return nullptr;
824 }
825 
FindVirtualMethodForInterfaceSuper(ArtMethod * method,PointerSize pointer_size)826 ArtMethod* Class::FindVirtualMethodForInterfaceSuper(ArtMethod* method, PointerSize pointer_size) {
827   DCHECK(method->GetDeclaringClass()->IsInterface());
828   DCHECK(IsInterface()) << "Should only be called on a interface class";
829   // Check if we have one defined on this interface first. This includes searching copied ones to
830   // get any conflict methods. Conflict methods are copied into each subtype from the supertype. We
831   // don't do any indirect method checks here.
832   for (ArtMethod& iface_method : GetVirtualMethods(pointer_size)) {
833     if (method->HasSameNameAndSignature(&iface_method)) {
834       return &iface_method;
835     }
836   }
837 
838   std::vector<ArtMethod*> abstract_methods;
839   // Search through the IFTable for a working version. We don't need to check for conflicts
840   // because if there was one it would appear in this classes virtual_methods_ above.
841 
842   Thread* self = Thread::Current();
843   StackHandleScope<2> hs(self);
844   MutableHandle<IfTable> iftable(hs.NewHandle(GetIfTable()));
845   MutableHandle<Class> iface(hs.NewHandle<Class>(nullptr));
846   size_t iftable_count = GetIfTableCount();
847   // Find the method. We don't need to check for conflicts because they would have been in the
848   // copied virtuals of this interface.  Order matters, traverse in reverse topological order; most
849   // subtypiest interfaces get visited first.
850   for (size_t k = iftable_count; k != 0;) {
851     k--;
852     DCHECK_LT(k, iftable->Count());
853     iface.Assign(iftable->GetInterface(k));
854     // Iterate through every declared method on this interface. Each direct method's name/signature
855     // is unique so the order of the inner loop doesn't matter.
856     for (auto& method_iter : iface->GetDeclaredVirtualMethods(pointer_size)) {
857       ArtMethod* current_method = &method_iter;
858       if (current_method->HasSameNameAndSignature(method)) {
859         if (current_method->IsDefault()) {
860           // Handle JLS soft errors, a default method from another superinterface tree can
861           // "override" an abstract method(s) from another superinterface tree(s).  To do this,
862           // ignore any [default] method which are dominated by the abstract methods we've seen so
863           // far. Check if overridden by any in abstract_methods. We do not need to check for
864           // default_conflicts because we would hit those before we get to this loop.
865           bool overridden = false;
866           for (ArtMethod* possible_override : abstract_methods) {
867             DCHECK(possible_override->HasSameNameAndSignature(current_method));
868             if (iface->IsAssignableFrom(possible_override->GetDeclaringClass())) {
869               overridden = true;
870               break;
871             }
872           }
873           if (!overridden) {
874             return current_method;
875           }
876         } else {
877           // Is not default.
878           // This might override another default method. Just stash it for now.
879           abstract_methods.push_back(current_method);
880         }
881       }
882     }
883   }
884   // If we reach here we either never found any declaration of the method (in which case
885   // 'abstract_methods' is empty or we found no non-overriden default methods in which case
886   // 'abstract_methods' contains a number of abstract implementations of the methods. We choose one
887   // of these arbitrarily.
888   return abstract_methods.empty() ? nullptr : abstract_methods[0];
889 }
890 
FindClassInitializer(PointerSize pointer_size)891 ArtMethod* Class::FindClassInitializer(PointerSize pointer_size) {
892   for (ArtMethod& method : GetDirectMethods(pointer_size)) {
893     if (method.IsClassInitializer()) {
894       DCHECK_STREQ(method.GetName(), "<clinit>");
895       DCHECK_STREQ(method.GetSignature().ToString().c_str(), "()V");
896       return &method;
897     }
898   }
899   return nullptr;
900 }
901 
902 // Custom binary search to avoid double comparisons from std::binary_search.
FindFieldByNameAndType(LengthPrefixedArray<ArtField> * fields,std::string_view name,std::string_view type)903 static ArtField* FindFieldByNameAndType(LengthPrefixedArray<ArtField>* fields,
904                                         std::string_view name,
905                                         std::string_view type)
906     REQUIRES_SHARED(Locks::mutator_lock_) {
907   if (fields == nullptr) {
908     return nullptr;
909   }
910   size_t low = 0;
911   size_t high = fields->size();
912   ArtField* ret = nullptr;
913   while (low < high) {
914     size_t mid = (low + high) / 2;
915     ArtField& field = fields->At(mid);
916     // Fields are sorted by class, then name, then type descriptor. This is verified in dex file
917     // verifier. There can be multiple fields with the same in the same class name due to proguard.
918     // Note: std::string_view::compare() uses lexicographical comparison and treats the `char` as
919     // unsigned; for modified-UTF-8 without embedded nulls this is consistent with the
920     // CompareModifiedUtf8ToModifiedUtf8AsUtf16CodePointValues() ordering.
921     int result = std::string_view(field.GetName()).compare(name);
922     if (result == 0) {
923       result = std::string_view(field.GetTypeDescriptor()).compare(type);
924     }
925     if (result < 0) {
926       low = mid + 1;
927     } else if (result > 0) {
928       high = mid;
929     } else {
930       ret = &field;
931       break;
932     }
933   }
934   if (kIsDebugBuild) {
935     ArtField* found = nullptr;
936     for (ArtField& field : MakeIterationRangeFromLengthPrefixedArray(fields)) {
937       if (name == field.GetName() && type == field.GetTypeDescriptor()) {
938         found = &field;
939         break;
940       }
941     }
942     CHECK_EQ(found, ret) << "Found " << found->PrettyField() << " vs  " << ret->PrettyField();
943   }
944   return ret;
945 }
946 
FindDeclaredInstanceField(std::string_view name,std::string_view type)947 ArtField* Class::FindDeclaredInstanceField(std::string_view name, std::string_view type) {
948   // Binary search by name. Interfaces are not relevant because they can't contain instance fields.
949   return FindFieldByNameAndType(GetIFieldsPtr(), name, type);
950 }
951 
FindDeclaredInstanceField(ObjPtr<DexCache> dex_cache,uint32_t dex_field_idx)952 ArtField* Class::FindDeclaredInstanceField(ObjPtr<DexCache> dex_cache, uint32_t dex_field_idx) {
953   if (GetDexCache() == dex_cache) {
954     for (ArtField& field : GetIFields()) {
955       if (field.GetDexFieldIndex() == dex_field_idx) {
956         return &field;
957       }
958     }
959   }
960   return nullptr;
961 }
962 
FindInstanceField(std::string_view name,std::string_view type)963 ArtField* Class::FindInstanceField(std::string_view name, std::string_view type) {
964   // Is the field in this class, or any of its superclasses?
965   // Interfaces are not relevant because they can't contain instance fields.
966   for (ObjPtr<Class> c = this; c != nullptr; c = c->GetSuperClass()) {
967     ArtField* f = c->FindDeclaredInstanceField(name, type);
968     if (f != nullptr) {
969       return f;
970     }
971   }
972   return nullptr;
973 }
974 
FindInstanceField(ObjPtr<DexCache> dex_cache,uint32_t dex_field_idx)975 ArtField* Class::FindInstanceField(ObjPtr<DexCache> dex_cache, uint32_t dex_field_idx) {
976   // Is the field in this class, or any of its superclasses?
977   // Interfaces are not relevant because they can't contain instance fields.
978   for (ObjPtr<Class> c = this; c != nullptr; c = c->GetSuperClass()) {
979     ArtField* f = c->FindDeclaredInstanceField(dex_cache, dex_field_idx);
980     if (f != nullptr) {
981       return f;
982     }
983   }
984   return nullptr;
985 }
986 
FindDeclaredStaticField(std::string_view name,std::string_view type)987 ArtField* Class::FindDeclaredStaticField(std::string_view name, std::string_view type) {
988   DCHECK(!type.empty());
989   return FindFieldByNameAndType(GetSFieldsPtr(), name, type);
990 }
991 
FindDeclaredStaticField(ObjPtr<DexCache> dex_cache,uint32_t dex_field_idx)992 ArtField* Class::FindDeclaredStaticField(ObjPtr<DexCache> dex_cache, uint32_t dex_field_idx) {
993   if (dex_cache == GetDexCache()) {
994     for (ArtField& field : GetSFields()) {
995       if (field.GetDexFieldIndex() == dex_field_idx) {
996         return &field;
997       }
998     }
999   }
1000   return nullptr;
1001 }
1002 
FindStaticField(Thread * self,ObjPtr<Class> klass,std::string_view name,std::string_view type)1003 ArtField* Class::FindStaticField(Thread* self,
1004                                  ObjPtr<Class> klass,
1005                                  std::string_view name,
1006                                  std::string_view type) {
1007   // Is the field in this class (or its interfaces), or any of its
1008   // superclasses (or their interfaces)?
1009   for (ObjPtr<Class> k = klass; k != nullptr; k = k->GetSuperClass()) {
1010     // Is the field in this class?
1011     ArtField* f = k->FindDeclaredStaticField(name, type);
1012     if (f != nullptr) {
1013       return f;
1014     }
1015     // Is this field in any of this class' interfaces?
1016     for (uint32_t i = 0, num_interfaces = k->NumDirectInterfaces(); i != num_interfaces; ++i) {
1017       ObjPtr<Class> interface = GetDirectInterface(self, k, i);
1018       DCHECK(interface != nullptr);
1019       f = FindStaticField(self, interface, name, type);
1020       if (f != nullptr) {
1021         return f;
1022       }
1023     }
1024   }
1025   return nullptr;
1026 }
1027 
FindStaticField(Thread * self,ObjPtr<Class> klass,ObjPtr<DexCache> dex_cache,uint32_t dex_field_idx)1028 ArtField* Class::FindStaticField(Thread* self,
1029                                  ObjPtr<Class> klass,
1030                                  ObjPtr<DexCache> dex_cache,
1031                                  uint32_t dex_field_idx) {
1032   for (ObjPtr<Class> k = klass; k != nullptr; k = k->GetSuperClass()) {
1033     // Is the field in this class?
1034     ArtField* f = k->FindDeclaredStaticField(dex_cache, dex_field_idx);
1035     if (f != nullptr) {
1036       return f;
1037     }
1038     // Though GetDirectInterface() should not cause thread suspension when called
1039     // from here, it takes a Handle as an argument, so we need to wrap `k`.
1040     ScopedAssertNoThreadSuspension ants(__FUNCTION__);
1041     // Is this field in any of this class' interfaces?
1042     for (uint32_t i = 0, num_interfaces = k->NumDirectInterfaces(); i != num_interfaces; ++i) {
1043       ObjPtr<Class> interface = GetDirectInterface(self, k, i);
1044       DCHECK(interface != nullptr);
1045       f = FindStaticField(self, interface, dex_cache, dex_field_idx);
1046       if (f != nullptr) {
1047         return f;
1048       }
1049     }
1050   }
1051   return nullptr;
1052 }
1053 
FindField(Thread * self,ObjPtr<Class> klass,std::string_view name,std::string_view type)1054 ArtField* Class::FindField(Thread* self,
1055                            ObjPtr<Class> klass,
1056                            std::string_view name,
1057                            std::string_view type) {
1058   // Find a field using the JLS field resolution order
1059   for (ObjPtr<Class> k = klass; k != nullptr; k = k->GetSuperClass()) {
1060     // Is the field in this class?
1061     ArtField* f = k->FindDeclaredInstanceField(name, type);
1062     if (f != nullptr) {
1063       return f;
1064     }
1065     f = k->FindDeclaredStaticField(name, type);
1066     if (f != nullptr) {
1067       return f;
1068     }
1069     // Is this field in any of this class' interfaces?
1070     for (uint32_t i = 0, num_interfaces = k->NumDirectInterfaces(); i != num_interfaces; ++i) {
1071       ObjPtr<Class> interface = GetDirectInterface(self, k, i);
1072       DCHECK(interface != nullptr);
1073       f = FindStaticField(self, interface, name, type);
1074       if (f != nullptr) {
1075         return f;
1076       }
1077     }
1078   }
1079   return nullptr;
1080 }
1081 
ClearSkipAccessChecksFlagOnAllMethods(PointerSize pointer_size)1082 void Class::ClearSkipAccessChecksFlagOnAllMethods(PointerSize pointer_size) {
1083   DCHECK(IsVerified());
1084   for (auto& m : GetMethods(pointer_size)) {
1085     if (!m.IsNative() && m.IsInvokable()) {
1086       m.ClearSkipAccessChecks();
1087     }
1088   }
1089 }
1090 
ClearMustCountLocksFlagOnAllMethods(PointerSize pointer_size)1091 void Class::ClearMustCountLocksFlagOnAllMethods(PointerSize pointer_size) {
1092   DCHECK(IsVerified());
1093   for (auto& m : GetMethods(pointer_size)) {
1094     if (!m.IsNative() && m.IsInvokable()) {
1095       m.ClearMustCountLocks();
1096     }
1097   }
1098 }
1099 
ClearDontCompileFlagOnAllMethods(PointerSize pointer_size)1100 void Class::ClearDontCompileFlagOnAllMethods(PointerSize pointer_size) {
1101   DCHECK(IsVerified());
1102   for (auto& m : GetMethods(pointer_size)) {
1103     if (!m.IsNative() && m.IsInvokable()) {
1104       m.ClearDontCompile();
1105     }
1106   }
1107 }
1108 
SetSkipAccessChecksFlagOnAllMethods(PointerSize pointer_size)1109 void Class::SetSkipAccessChecksFlagOnAllMethods(PointerSize pointer_size) {
1110   DCHECK(IsVerified());
1111   for (auto& m : GetMethods(pointer_size)) {
1112     if (!m.IsNative() && m.IsInvokable()) {
1113       m.SetSkipAccessChecks();
1114     }
1115   }
1116 }
1117 
GetDescriptor(std::string * storage)1118 const char* Class::GetDescriptor(std::string* storage) {
1119   size_t dim = 0u;
1120   ObjPtr<mirror::Class> klass = this;
1121   while (klass->IsArrayClass()) {
1122     ++dim;
1123     // No read barrier needed, we're reading a chain of constant references for comparison
1124     // with null. Then we follow up below with reading constant references to read constant
1125     // primitive data in both proxy and non-proxy paths. See ReadBarrierOption.
1126     klass = klass->GetComponentType<kDefaultVerifyFlags, kWithoutReadBarrier>();
1127   }
1128   if (klass->IsProxyClass()) {
1129     // No read barrier needed, the `name` field is constant for proxy classes and
1130     // the contents of the String are also constant. See ReadBarrierOption.
1131     ObjPtr<mirror::String> name = klass->GetName<kVerifyNone, kWithoutReadBarrier>();
1132     DCHECK(name != nullptr);
1133     *storage = DotToDescriptor(name->ToModifiedUtf8().c_str());
1134   } else {
1135     const char* descriptor;
1136     if (klass->IsPrimitive()) {
1137       descriptor = Primitive::Descriptor(klass->GetPrimitiveType());
1138     } else {
1139       const DexFile& dex_file = klass->GetDexFile();
1140       const dex::TypeId& type_id = dex_file.GetTypeId(klass->GetDexTypeIndex());
1141       descriptor = dex_file.GetTypeDescriptor(type_id);
1142     }
1143     if (dim == 0) {
1144       return descriptor;
1145     }
1146     *storage = descriptor;
1147   }
1148   storage->insert(0u, dim, '[');
1149   return storage->c_str();
1150 }
1151 
GetClassDef()1152 const dex::ClassDef* Class::GetClassDef() {
1153   uint16_t class_def_idx = GetDexClassDefIndex();
1154   if (class_def_idx == DexFile::kDexNoIndex16) {
1155     return nullptr;
1156   }
1157   return &GetDexFile().GetClassDef(class_def_idx);
1158 }
1159 
GetDirectInterfaceTypeIdx(uint32_t idx)1160 dex::TypeIndex Class::GetDirectInterfaceTypeIdx(uint32_t idx) {
1161   DCHECK(!IsPrimitive());
1162   DCHECK(!IsArrayClass());
1163   return GetInterfaceTypeList()->GetTypeItem(idx).type_idx_;
1164 }
1165 
GetDirectInterface(Thread * self,ObjPtr<Class> klass,uint32_t idx)1166 ObjPtr<Class> Class::GetDirectInterface(Thread* self, ObjPtr<Class> klass, uint32_t idx) {
1167   DCHECK(klass != nullptr);
1168   DCHECK(!klass->IsPrimitive());
1169   if (klass->IsArrayClass()) {
1170     ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
1171     // Use ClassLinker::LookupClass(); avoid poisoning ObjPtr<>s by ClassLinker::FindSystemClass().
1172     ObjPtr<Class> interface;
1173     if (idx == 0) {
1174       interface = class_linker->LookupClass(self, "Ljava/lang/Cloneable;", nullptr);
1175     } else {
1176       DCHECK_EQ(1U, idx);
1177       interface = class_linker->LookupClass(self, "Ljava/io/Serializable;", nullptr);
1178     }
1179     DCHECK(interface != nullptr);
1180     return interface;
1181   } else if (klass->IsProxyClass()) {
1182     ObjPtr<ObjectArray<Class>> interfaces = klass->GetProxyInterfaces();
1183     DCHECK(interfaces != nullptr);
1184     return interfaces->Get(idx);
1185   } else {
1186     dex::TypeIndex type_idx = klass->GetDirectInterfaceTypeIdx(idx);
1187     ObjPtr<Class> interface = Runtime::Current()->GetClassLinker()->LookupResolvedType(
1188         type_idx, klass->GetDexCache(), klass->GetClassLoader());
1189     return interface;
1190   }
1191 }
1192 
ResolveDirectInterface(Thread * self,Handle<Class> klass,uint32_t idx)1193 ObjPtr<Class> Class::ResolveDirectInterface(Thread* self, Handle<Class> klass, uint32_t idx) {
1194   ObjPtr<Class> interface = GetDirectInterface(self, klass.Get(), idx);
1195   if (interface == nullptr) {
1196     DCHECK(!klass->IsArrayClass());
1197     DCHECK(!klass->IsProxyClass());
1198     dex::TypeIndex type_idx = klass->GetDirectInterfaceTypeIdx(idx);
1199     interface = Runtime::Current()->GetClassLinker()->ResolveType(type_idx, klass.Get());
1200     CHECK(interface != nullptr || self->IsExceptionPending());
1201   }
1202   return interface;
1203 }
1204 
GetCommonSuperClass(Handle<Class> klass)1205 ObjPtr<Class> Class::GetCommonSuperClass(Handle<Class> klass) {
1206   DCHECK(klass != nullptr);
1207   DCHECK(!klass->IsInterface());
1208   DCHECK(!IsInterface());
1209   ObjPtr<Class> common_super_class = this;
1210   while (!common_super_class->IsAssignableFrom(klass.Get())) {
1211     ObjPtr<Class> old_common = common_super_class;
1212     common_super_class = old_common->GetSuperClass();
1213     DCHECK(common_super_class != nullptr) << old_common->PrettyClass();
1214   }
1215   return common_super_class;
1216 }
1217 
GetSourceFile()1218 const char* Class::GetSourceFile() {
1219   const DexFile& dex_file = GetDexFile();
1220   const dex::ClassDef* dex_class_def = GetClassDef();
1221   if (dex_class_def == nullptr) {
1222     // Generated classes have no class def.
1223     return nullptr;
1224   }
1225   return dex_file.GetSourceFile(*dex_class_def);
1226 }
1227 
GetLocation()1228 std::string Class::GetLocation() {
1229   ObjPtr<DexCache> dex_cache = GetDexCache();
1230   if (dex_cache != nullptr && !IsProxyClass()) {
1231     return dex_cache->GetLocation()->ToModifiedUtf8();
1232   }
1233   // Arrays and proxies are generated and have no corresponding dex file location.
1234   return "generated class";
1235 }
1236 
GetInterfaceTypeList()1237 const dex::TypeList* Class::GetInterfaceTypeList() {
1238   const dex::ClassDef* class_def = GetClassDef();
1239   if (class_def == nullptr) {
1240     return nullptr;
1241   }
1242   return GetDexFile().GetInterfacesList(*class_def);
1243 }
1244 
PopulateEmbeddedVTable(PointerSize pointer_size)1245 void Class::PopulateEmbeddedVTable(PointerSize pointer_size) {
1246   ObjPtr<PointerArray> table = GetVTableDuringLinking();
1247   CHECK(table != nullptr) << PrettyClass();
1248   const size_t table_length = table->GetLength();
1249   SetEmbeddedVTableLength(table_length);
1250   for (size_t i = 0; i < table_length; i++) {
1251     SetEmbeddedVTableEntry(i, table->GetElementPtrSize<ArtMethod*>(i, pointer_size), pointer_size);
1252   }
1253   // Keep java.lang.Object class's vtable around for since it's easier
1254   // to be reused by array classes during their linking.
1255   if (!IsObjectClass()) {
1256     SetVTable(nullptr);
1257   }
1258 }
1259 
1260 class ReadBarrierOnNativeRootsVisitor {
1261  public:
operator ()(ObjPtr<Object> obj ATTRIBUTE_UNUSED,MemberOffset offset ATTRIBUTE_UNUSED,bool is_static ATTRIBUTE_UNUSED) const1262   void operator()(ObjPtr<Object> obj ATTRIBUTE_UNUSED,
1263                   MemberOffset offset ATTRIBUTE_UNUSED,
1264                   bool is_static ATTRIBUTE_UNUSED) const {}
1265 
VisitRootIfNonNull(CompressedReference<Object> * root) const1266   void VisitRootIfNonNull(CompressedReference<Object>* root) const
1267       REQUIRES_SHARED(Locks::mutator_lock_) {
1268     if (!root->IsNull()) {
1269       VisitRoot(root);
1270     }
1271   }
1272 
VisitRoot(CompressedReference<Object> * root) const1273   void VisitRoot(CompressedReference<Object>* root) const
1274       REQUIRES_SHARED(Locks::mutator_lock_) {
1275     ObjPtr<Object> old_ref = root->AsMirrorPtr();
1276     ObjPtr<Object> new_ref = ReadBarrier::BarrierForRoot(root);
1277     if (old_ref != new_ref) {
1278       // Update the field atomically. This may fail if mutator updates before us, but it's ok.
1279       auto* atomic_root =
1280           reinterpret_cast<Atomic<CompressedReference<Object>>*>(root);
1281       atomic_root->CompareAndSetStrongSequentiallyConsistent(
1282           CompressedReference<Object>::FromMirrorPtr(old_ref.Ptr()),
1283           CompressedReference<Object>::FromMirrorPtr(new_ref.Ptr()));
1284     }
1285   }
1286 };
1287 
1288 // The pre-fence visitor for Class::CopyOf().
1289 class CopyClassVisitor {
1290  public:
CopyClassVisitor(Thread * self,Handle<Class> * orig,size_t new_length,size_t copy_bytes,ImTable * imt,PointerSize pointer_size)1291   CopyClassVisitor(Thread* self,
1292                    Handle<Class>* orig,
1293                    size_t new_length,
1294                    size_t copy_bytes,
1295                    ImTable* imt,
1296                    PointerSize pointer_size)
1297       : self_(self), orig_(orig), new_length_(new_length),
1298         copy_bytes_(copy_bytes), imt_(imt), pointer_size_(pointer_size) {
1299   }
1300 
operator ()(ObjPtr<Object> obj,size_t usable_size ATTRIBUTE_UNUSED) const1301   void operator()(ObjPtr<Object> obj, size_t usable_size ATTRIBUTE_UNUSED) const
1302       REQUIRES_SHARED(Locks::mutator_lock_) {
1303     StackHandleScope<1> hs(self_);
1304     Handle<mirror::Class> h_new_class_obj(hs.NewHandle(obj->AsClass()));
1305     Object::CopyObject(h_new_class_obj.Get(), orig_->Get(), copy_bytes_);
1306     Class::SetStatus(h_new_class_obj, ClassStatus::kResolving, self_);
1307     h_new_class_obj->PopulateEmbeddedVTable(pointer_size_);
1308     h_new_class_obj->SetImt(imt_, pointer_size_);
1309     h_new_class_obj->SetClassSize(new_length_);
1310     // Visit all of the references to make sure there is no from space references in the native
1311     // roots.
1312     h_new_class_obj->Object::VisitReferences(ReadBarrierOnNativeRootsVisitor(), VoidFunctor());
1313   }
1314 
1315  private:
1316   Thread* const self_;
1317   Handle<Class>* const orig_;
1318   const size_t new_length_;
1319   const size_t copy_bytes_;
1320   ImTable* imt_;
1321   const PointerSize pointer_size_;
1322   DISALLOW_COPY_AND_ASSIGN(CopyClassVisitor);
1323 };
1324 
CopyOf(Handle<Class> h_this,Thread * self,int32_t new_length,ImTable * imt,PointerSize pointer_size)1325 ObjPtr<Class> Class::CopyOf(Handle<Class> h_this,
1326                             Thread* self,
1327                             int32_t new_length,
1328                             ImTable* imt,
1329                             PointerSize pointer_size) {
1330   DCHECK_GE(new_length, static_cast<int32_t>(sizeof(Class)));
1331   // We may get copied by a compacting GC.
1332   Runtime* runtime = Runtime::Current();
1333   gc::Heap* heap = runtime->GetHeap();
1334   // The num_bytes (3rd param) is sizeof(Class) as opposed to SizeOf()
1335   // to skip copying the tail part that we will overwrite here.
1336   CopyClassVisitor visitor(self, &h_this, new_length, sizeof(Class), imt, pointer_size);
1337   ObjPtr<mirror::Class> java_lang_Class = GetClassRoot<mirror::Class>(runtime->GetClassLinker());
1338   ObjPtr<Object> new_class = kMovingClasses ?
1339       heap->AllocObject(self, java_lang_Class, new_length, visitor) :
1340       heap->AllocNonMovableObject(self, java_lang_Class, new_length, visitor);
1341   if (UNLIKELY(new_class == nullptr)) {
1342     self->AssertPendingOOMException();
1343     return nullptr;
1344   }
1345   return new_class->AsClass();
1346 }
1347 
ProxyDescriptorEquals(const char * match)1348 bool Class::ProxyDescriptorEquals(const char* match) {
1349   DCHECK(IsProxyClass());
1350   std::string storage;
1351   const char* descriptor = GetDescriptor(&storage);
1352   DCHECK(descriptor == storage.c_str());
1353   return storage == match;
1354 }
1355 
1356 // TODO: Move this to java_lang_Class.cc?
GetDeclaredConstructor(Thread * self,Handle<ObjectArray<Class>> args,PointerSize pointer_size)1357 ArtMethod* Class::GetDeclaredConstructor(
1358     Thread* self, Handle<ObjectArray<Class>> args, PointerSize pointer_size) {
1359   for (auto& m : GetDirectMethods(pointer_size)) {
1360     // Skip <clinit> which is a static constructor, as well as non constructors.
1361     if (m.IsStatic() || !m.IsConstructor()) {
1362       continue;
1363     }
1364     // May cause thread suspension and exceptions.
1365     if (m.GetInterfaceMethodIfProxy(kRuntimePointerSize)->EqualParameters(args)) {
1366       return &m;
1367     }
1368     if (UNLIKELY(self->IsExceptionPending())) {
1369       return nullptr;
1370     }
1371   }
1372   return nullptr;
1373 }
1374 
Depth()1375 uint32_t Class::Depth() {
1376   uint32_t depth = 0;
1377   for (ObjPtr<Class> cls = this; cls->GetSuperClass() != nullptr; cls = cls->GetSuperClass()) {
1378     depth++;
1379   }
1380   return depth;
1381 }
1382 
FindTypeIndexInOtherDexFile(const DexFile & dex_file)1383 dex::TypeIndex Class::FindTypeIndexInOtherDexFile(const DexFile& dex_file) {
1384   std::string temp;
1385   const dex::TypeId* type_id = dex_file.FindTypeId(GetDescriptor(&temp));
1386   return (type_id == nullptr) ? dex::TypeIndex() : dex_file.GetIndexForTypeId(*type_id);
1387 }
1388 
1389 ALWAYS_INLINE
IsMethodPreferredOver(ArtMethod * orig_method,bool orig_method_hidden,ArtMethod * new_method,bool new_method_hidden)1390 static bool IsMethodPreferredOver(ArtMethod* orig_method,
1391                                   bool orig_method_hidden,
1392                                   ArtMethod* new_method,
1393                                   bool new_method_hidden) {
1394   DCHECK(new_method != nullptr);
1395 
1396   // Is this the first result?
1397   if (orig_method == nullptr) {
1398     return true;
1399   }
1400 
1401   // Original method is hidden, the new one is not?
1402   if (orig_method_hidden && !new_method_hidden) {
1403     return true;
1404   }
1405 
1406   // We iterate over virtual methods first and then over direct ones,
1407   // so we can never be in situation where `orig_method` is direct and
1408   // `new_method` is virtual.
1409   DCHECK(!orig_method->IsDirect() || new_method->IsDirect());
1410 
1411   // Original method is synthetic, the new one is not?
1412   if (orig_method->IsSynthetic() && !new_method->IsSynthetic()) {
1413     return true;
1414   }
1415 
1416   return false;
1417 }
1418 
1419 template <PointerSize kPointerSize>
GetDeclaredMethodInternal(Thread * self,ObjPtr<Class> klass,ObjPtr<String> name,ObjPtr<ObjectArray<Class>> args,const std::function<hiddenapi::AccessContext ()> & fn_get_access_context)1420 ObjPtr<Method> Class::GetDeclaredMethodInternal(
1421     Thread* self,
1422     ObjPtr<Class> klass,
1423     ObjPtr<String> name,
1424     ObjPtr<ObjectArray<Class>> args,
1425     const std::function<hiddenapi::AccessContext()>& fn_get_access_context) {
1426   // Covariant return types (or smali) permit the class to define
1427   // multiple methods with the same name and parameter types.
1428   // Prefer (in decreasing order of importance):
1429   //  1) non-hidden method over hidden
1430   //  2) virtual methods over direct
1431   //  3) non-synthetic methods over synthetic
1432   // We never return miranda methods that were synthesized by the runtime.
1433   StackHandleScope<3> hs(self);
1434   auto h_method_name = hs.NewHandle(name);
1435   if (UNLIKELY(h_method_name == nullptr)) {
1436     ThrowNullPointerException("name == null");
1437     return nullptr;
1438   }
1439   auto h_args = hs.NewHandle(args);
1440   Handle<Class> h_klass = hs.NewHandle(klass);
1441   constexpr hiddenapi::AccessMethod access_method = hiddenapi::AccessMethod::kNone;
1442   ArtMethod* result = nullptr;
1443   bool result_hidden = false;
1444   for (auto& m : h_klass->GetDeclaredVirtualMethods(kPointerSize)) {
1445     if (m.IsMiranda()) {
1446       continue;
1447     }
1448     auto* np_method = m.GetInterfaceMethodIfProxy(kPointerSize);
1449     // May cause thread suspension.
1450     ObjPtr<String> np_name = np_method->ResolveNameString();
1451     if (!np_name->Equals(h_method_name.Get()) || !np_method->EqualParameters(h_args)) {
1452       if (UNLIKELY(self->IsExceptionPending())) {
1453         return nullptr;
1454       }
1455       continue;
1456     }
1457     bool m_hidden = hiddenapi::ShouldDenyAccessToMember(&m, fn_get_access_context, access_method);
1458     if (!m_hidden && !m.IsSynthetic()) {
1459       // Non-hidden, virtual, non-synthetic. Best possible result, exit early.
1460       return Method::CreateFromArtMethod<kPointerSize>(self, &m);
1461     } else if (IsMethodPreferredOver(result, result_hidden, &m, m_hidden)) {
1462       // Remember as potential result.
1463       result = &m;
1464       result_hidden = m_hidden;
1465     }
1466   }
1467 
1468   if ((result != nullptr) && !result_hidden) {
1469     // We have not found a non-hidden, virtual, non-synthetic method, but
1470     // if we have found a non-hidden, virtual, synthetic method, we cannot
1471     // do better than that later.
1472     DCHECK(!result->IsDirect());
1473     DCHECK(result->IsSynthetic());
1474   } else {
1475     for (auto& m : h_klass->GetDirectMethods(kPointerSize)) {
1476       auto modifiers = m.GetAccessFlags();
1477       if ((modifiers & kAccConstructor) != 0) {
1478         continue;
1479       }
1480       auto* np_method = m.GetInterfaceMethodIfProxy(kPointerSize);
1481       // May cause thread suspension.
1482       ObjPtr<String> np_name = np_method->ResolveNameString();
1483       if (np_name == nullptr) {
1484         self->AssertPendingException();
1485         return nullptr;
1486       }
1487       if (!np_name->Equals(h_method_name.Get()) || !np_method->EqualParameters(h_args)) {
1488         if (UNLIKELY(self->IsExceptionPending())) {
1489           return nullptr;
1490         }
1491         continue;
1492       }
1493       DCHECK(!m.IsMiranda());  // Direct methods cannot be miranda methods.
1494       bool m_hidden = hiddenapi::ShouldDenyAccessToMember(&m, fn_get_access_context, access_method);
1495       if (!m_hidden && !m.IsSynthetic()) {
1496         // Non-hidden, direct, non-synthetic. Any virtual result could only have been
1497         // hidden, therefore this is the best possible match. Exit now.
1498         DCHECK((result == nullptr) || result_hidden);
1499         return Method::CreateFromArtMethod<kPointerSize>(self, &m);
1500       } else if (IsMethodPreferredOver(result, result_hidden, &m, m_hidden)) {
1501         // Remember as potential result.
1502         result = &m;
1503         result_hidden = m_hidden;
1504       }
1505     }
1506   }
1507 
1508   return result != nullptr
1509       ? Method::CreateFromArtMethod<kPointerSize>(self, result)
1510       : nullptr;
1511 }
1512 
1513 template
1514 ObjPtr<Method> Class::GetDeclaredMethodInternal<PointerSize::k32>(
1515     Thread* self,
1516     ObjPtr<Class> klass,
1517     ObjPtr<String> name,
1518     ObjPtr<ObjectArray<Class>> args,
1519     const std::function<hiddenapi::AccessContext()>& fn_get_access_context);
1520 template
1521 ObjPtr<Method> Class::GetDeclaredMethodInternal<PointerSize::k64>(
1522     Thread* self,
1523     ObjPtr<Class> klass,
1524     ObjPtr<String> name,
1525     ObjPtr<ObjectArray<Class>> args,
1526     const std::function<hiddenapi::AccessContext()>& fn_get_access_context);
1527 
1528 template <PointerSize kPointerSize>
GetDeclaredConstructorInternal(Thread * self,ObjPtr<Class> klass,ObjPtr<ObjectArray<Class>> args)1529 ObjPtr<Constructor> Class::GetDeclaredConstructorInternal(
1530     Thread* self,
1531     ObjPtr<Class> klass,
1532     ObjPtr<ObjectArray<Class>> args) {
1533   StackHandleScope<1> hs(self);
1534   ArtMethod* result = klass->GetDeclaredConstructor(self, hs.NewHandle(args), kPointerSize);
1535   return result != nullptr
1536       ? Constructor::CreateFromArtMethod<kPointerSize>(self, result)
1537       : nullptr;
1538 }
1539 
1540 // Constructor::CreateFromArtMethod<kTransactionActive>(self, result)
1541 
1542 template
1543 ObjPtr<Constructor> Class::GetDeclaredConstructorInternal<PointerSize::k32>(
1544     Thread* self,
1545     ObjPtr<Class> klass,
1546     ObjPtr<ObjectArray<Class>> args);
1547 template
1548 ObjPtr<Constructor> Class::GetDeclaredConstructorInternal<PointerSize::k64>(
1549     Thread* self,
1550     ObjPtr<Class> klass,
1551     ObjPtr<ObjectArray<Class>> args);
1552 
GetInnerClassFlags(Handle<Class> h_this,int32_t default_value)1553 int32_t Class::GetInnerClassFlags(Handle<Class> h_this, int32_t default_value) {
1554   if (h_this->IsProxyClass() || h_this->GetDexCache() == nullptr) {
1555     return default_value;
1556   }
1557   uint32_t flags;
1558   if (!annotations::GetInnerClassFlags(h_this, &flags)) {
1559     return default_value;
1560   }
1561   return flags;
1562 }
1563 
SetObjectSizeAllocFastPath(uint32_t new_object_size)1564 void Class::SetObjectSizeAllocFastPath(uint32_t new_object_size) {
1565   if (Runtime::Current()->IsActiveTransaction()) {
1566     SetField32Volatile<true>(ObjectSizeAllocFastPathOffset(), new_object_size);
1567   } else {
1568     SetField32Volatile<false>(ObjectSizeAllocFastPathOffset(), new_object_size);
1569   }
1570 }
1571 
PrettyDescriptor(ObjPtr<mirror::Class> klass)1572 std::string Class::PrettyDescriptor(ObjPtr<mirror::Class> klass) {
1573   if (klass == nullptr) {
1574     return "null";
1575   }
1576   return klass->PrettyDescriptor();
1577 }
1578 
PrettyDescriptor()1579 std::string Class::PrettyDescriptor() {
1580   std::string temp;
1581   return art::PrettyDescriptor(GetDescriptor(&temp));
1582 }
1583 
PrettyClass(ObjPtr<mirror::Class> c)1584 std::string Class::PrettyClass(ObjPtr<mirror::Class> c) {
1585   if (c == nullptr) {
1586     return "null";
1587   }
1588   return c->PrettyClass();
1589 }
1590 
PrettyClass()1591 std::string Class::PrettyClass() {
1592   std::string result;
1593   if (IsObsoleteObject()) {
1594     result += "(Obsolete)";
1595   }
1596   if (IsRetired()) {
1597     result += "(Retired)";
1598   }
1599   result += "java.lang.Class<";
1600   result += PrettyDescriptor();
1601   result += ">";
1602   return result;
1603 }
1604 
PrettyClassAndClassLoader(ObjPtr<mirror::Class> c)1605 std::string Class::PrettyClassAndClassLoader(ObjPtr<mirror::Class> c) {
1606   if (c == nullptr) {
1607     return "null";
1608   }
1609   return c->PrettyClassAndClassLoader();
1610 }
1611 
PrettyClassAndClassLoader()1612 std::string Class::PrettyClassAndClassLoader() {
1613   std::string result;
1614   result += "java.lang.Class<";
1615   result += PrettyDescriptor();
1616   result += ",";
1617   result += mirror::Object::PrettyTypeOf(GetClassLoader());
1618   // TODO: add an identifying hash value for the loader
1619   result += ">";
1620   return result;
1621 }
1622 
GetAccessFlagsDCheck()1623 template<VerifyObjectFlags kVerifyFlags> void Class::GetAccessFlagsDCheck() {
1624   // Check class is loaded/retired or this is java.lang.String that has a
1625   // circularity issue during loading the names of its members
1626   DCHECK(IsIdxLoaded<kVerifyFlags>() || IsRetired<kVerifyFlags>() ||
1627          IsErroneous<static_cast<VerifyObjectFlags>(kVerifyFlags & ~kVerifyThis)>() ||
1628          this == GetClassRoot<String>())
1629               << "IsIdxLoaded=" << IsIdxLoaded<kVerifyFlags>()
1630               << " IsRetired=" << IsRetired<kVerifyFlags>()
1631               << " IsErroneous=" <<
1632               IsErroneous<static_cast<VerifyObjectFlags>(kVerifyFlags & ~kVerifyThis)>()
1633               << " IsString=" << (this == GetClassRoot<String>())
1634               << " status= " << GetStatus<kVerifyFlags>()
1635               << " descriptor=" << PrettyDescriptor();
1636 }
1637 // Instantiate the common cases.
1638 template void Class::GetAccessFlagsDCheck<kVerifyNone>();
1639 template void Class::GetAccessFlagsDCheck<kVerifyThis>();
1640 template void Class::GetAccessFlagsDCheck<kVerifyReads>();
1641 template void Class::GetAccessFlagsDCheck<kVerifyWrites>();
1642 template void Class::GetAccessFlagsDCheck<kVerifyAll>();
1643 
SetAccessFlagsDCheck(uint32_t new_access_flags)1644 void Class::SetAccessFlagsDCheck(uint32_t new_access_flags) {
1645   uint32_t old_access_flags = GetField32<kVerifyNone>(AccessFlagsOffset());
1646   // kAccVerificationAttempted is retained.
1647   CHECK((old_access_flags & kAccVerificationAttempted) == 0 ||
1648         (new_access_flags & kAccVerificationAttempted) != 0);
1649 }
1650 
GetMethodIds()1651 ObjPtr<Object> Class::GetMethodIds() {
1652   ObjPtr<ClassExt> ext(GetExtData());
1653   if (ext.IsNull()) {
1654     return nullptr;
1655   } else {
1656     return ext->GetJMethodIDs();
1657   }
1658 }
EnsureMethodIds(Handle<Class> h_this)1659 bool Class::EnsureMethodIds(Handle<Class> h_this) {
1660   DCHECK_NE(Runtime::Current()->GetJniIdType(), JniIdType::kPointer) << "JNI Ids are pointers!";
1661   Thread* self = Thread::Current();
1662   ObjPtr<ClassExt> ext(EnsureExtDataPresent(h_this, self));
1663   if (ext.IsNull()) {
1664     self->AssertPendingOOMException();
1665     return false;
1666   }
1667   return ext->EnsureJMethodIDsArrayPresent(h_this->NumMethods());
1668 }
1669 
GetStaticFieldIds()1670 ObjPtr<Object> Class::GetStaticFieldIds() {
1671   ObjPtr<ClassExt> ext(GetExtData());
1672   if (ext.IsNull()) {
1673     return nullptr;
1674   } else {
1675     return ext->GetStaticJFieldIDs();
1676   }
1677 }
EnsureStaticFieldIds(Handle<Class> h_this)1678 bool Class::EnsureStaticFieldIds(Handle<Class> h_this) {
1679   DCHECK_NE(Runtime::Current()->GetJniIdType(), JniIdType::kPointer) << "JNI Ids are pointers!";
1680   Thread* self = Thread::Current();
1681   ObjPtr<ClassExt> ext(EnsureExtDataPresent(h_this, self));
1682   if (ext.IsNull()) {
1683     self->AssertPendingOOMException();
1684     return false;
1685   }
1686   return ext->EnsureStaticJFieldIDsArrayPresent(h_this->NumStaticFields());
1687 }
GetInstanceFieldIds()1688 ObjPtr<Object> Class::GetInstanceFieldIds() {
1689   ObjPtr<ClassExt> ext(GetExtData());
1690   if (ext.IsNull()) {
1691     return nullptr;
1692   } else {
1693     return ext->GetInstanceJFieldIDs();
1694   }
1695 }
EnsureInstanceFieldIds(Handle<Class> h_this)1696 bool Class::EnsureInstanceFieldIds(Handle<Class> h_this) {
1697   DCHECK_NE(Runtime::Current()->GetJniIdType(), JniIdType::kPointer) << "JNI Ids are pointers!";
1698   Thread* self = Thread::Current();
1699   ObjPtr<ClassExt> ext(EnsureExtDataPresent(h_this, self));
1700   if (ext.IsNull()) {
1701     self->AssertPendingOOMException();
1702     return false;
1703   }
1704   return ext->EnsureInstanceJFieldIDsArrayPresent(h_this->NumInstanceFields());
1705 }
1706 
GetStaticFieldIdOffset(ArtField * field)1707 size_t Class::GetStaticFieldIdOffset(ArtField* field) {
1708   DCHECK_LT(reinterpret_cast<uintptr_t>(field),
1709             reinterpret_cast<uintptr_t>(&*GetSFieldsPtr()->end()))
1710       << "field not part of the current class. " << field->PrettyField() << " class is "
1711       << PrettyClass();
1712   DCHECK_GE(reinterpret_cast<uintptr_t>(field),
1713             reinterpret_cast<uintptr_t>(&*GetSFieldsPtr()->begin()))
1714       << "field not part of the current class. " << field->PrettyField() << " class is "
1715       << PrettyClass();
1716   uintptr_t start = reinterpret_cast<uintptr_t>(&GetSFieldsPtr()->At(0));
1717   uintptr_t fld = reinterpret_cast<uintptr_t>(field);
1718   size_t res = (fld - start) / sizeof(ArtField);
1719   DCHECK_EQ(&GetSFieldsPtr()->At(res), field)
1720       << "Incorrect field computation expected: " << field->PrettyField()
1721       << " got: " << GetSFieldsPtr()->At(res).PrettyField();
1722   return res;
1723 }
1724 
GetInstanceFieldIdOffset(ArtField * field)1725 size_t Class::GetInstanceFieldIdOffset(ArtField* field) {
1726   DCHECK_LT(reinterpret_cast<uintptr_t>(field),
1727             reinterpret_cast<uintptr_t>(&*GetIFieldsPtr()->end()))
1728       << "field not part of the current class. " << field->PrettyField() << " class is "
1729       << PrettyClass();
1730   DCHECK_GE(reinterpret_cast<uintptr_t>(field),
1731             reinterpret_cast<uintptr_t>(&*GetIFieldsPtr()->begin()))
1732       << "field not part of the current class. " << field->PrettyField() << " class is "
1733       << PrettyClass();
1734   uintptr_t start = reinterpret_cast<uintptr_t>(&GetIFieldsPtr()->At(0));
1735   uintptr_t fld = reinterpret_cast<uintptr_t>(field);
1736   size_t res = (fld - start) / sizeof(ArtField);
1737   DCHECK_EQ(&GetIFieldsPtr()->At(res), field)
1738       << "Incorrect field computation expected: " << field->PrettyField()
1739       << " got: " << GetIFieldsPtr()->At(res).PrettyField();
1740   return res;
1741 }
1742 
GetMethodIdOffset(ArtMethod * method,PointerSize pointer_size)1743 size_t Class::GetMethodIdOffset(ArtMethod* method, PointerSize pointer_size) {
1744   DCHECK(GetMethodsSlice(kRuntimePointerSize).Contains(method))
1745       << "method not part of the current class. " << method->PrettyMethod() << "( " << reinterpret_cast<void*>(method) << ")" << " class is "
1746       << PrettyClass() << [&]() REQUIRES_SHARED(Locks::mutator_lock_) {
1747         std::ostringstream os;
1748         os << " Methods are [";
1749         for (ArtMethod& m : GetMethodsSlice(kRuntimePointerSize)) {
1750           os << m.PrettyMethod() << "( " << reinterpret_cast<void*>(&m) << "), ";
1751         }
1752         os << "]";
1753         return os.str();
1754       }();
1755   uintptr_t start = reinterpret_cast<uintptr_t>(&*GetMethodsSlice(pointer_size).begin());
1756   uintptr_t fld = reinterpret_cast<uintptr_t>(method);
1757   size_t art_method_size = ArtMethod::Size(pointer_size);
1758   size_t art_method_align = ArtMethod::Alignment(pointer_size);
1759   size_t res = (fld - start) / art_method_size;
1760   DCHECK_EQ(&GetMethodsPtr()->At(res, art_method_size, art_method_align), method)
1761       << "Incorrect method computation expected: " << method->PrettyMethod()
1762       << " got: " << GetMethodsPtr()->At(res, art_method_size, art_method_align).PrettyMethod();
1763   return res;
1764 }
1765 
FindAccessibleInterfaceMethod(ArtMethod * implementation_method,PointerSize pointer_size)1766 ArtMethod* Class::FindAccessibleInterfaceMethod(ArtMethod* implementation_method,
1767                                                 PointerSize pointer_size)
1768     REQUIRES_SHARED(Locks::mutator_lock_) {
1769   ObjPtr<mirror::IfTable> iftable = GetIfTable();
1770   for (int32_t i = 0, iftable_count = iftable->Count(); i < iftable_count; ++i) {
1771     ObjPtr<mirror::PointerArray> methods = iftable->GetMethodArrayOrNull(i);
1772     if (methods == nullptr) {
1773       continue;
1774     }
1775     for (size_t j = 0, count = iftable->GetMethodArrayCount(i); j < count; ++j) {
1776       if (implementation_method == methods->GetElementPtrSize<ArtMethod*>(j, pointer_size)) {
1777         ObjPtr<mirror::Class> iface = iftable->GetInterface(i);
1778         ArtMethod* interface_method = &iface->GetVirtualMethodsSlice(pointer_size)[j];
1779         // If the interface method is part of the public SDK, return it.
1780         if ((hiddenapi::GetRuntimeFlags(interface_method) & kAccPublicApi) != 0) {
1781           return interface_method;
1782         }
1783       }
1784     }
1785   }
1786   return nullptr;
1787 }
1788 
1789 
1790 }  // namespace mirror
1791 }  // namespace art
1792