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      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 "art_method.h"
     18 
     19 #include <cstddef>
     20 
     21 #include "android-base/stringprintf.h"
     22 
     23 #include "arch/context.h"
     24 #include "art_method-inl.h"
     25 #include "base/stringpiece.h"
     26 #include "class_linker-inl.h"
     27 #include "debugger.h"
     28 #include "dex_file-inl.h"
     29 #include "dex_file_annotations.h"
     30 #include "dex_instruction.h"
     31 #include "entrypoints/runtime_asm_entrypoints.h"
     32 #include "gc/accounting/card_table-inl.h"
     33 #include "interpreter/interpreter.h"
     34 #include "jit/jit.h"
     35 #include "jit/jit_code_cache.h"
     36 #include "jit/profiling_info.h"
     37 #include "jni_internal.h"
     38 #include "mirror/class-inl.h"
     39 #include "mirror/class_ext.h"
     40 #include "mirror/executable.h"
     41 #include "mirror/object_array-inl.h"
     42 #include "mirror/object-inl.h"
     43 #include "mirror/string.h"
     44 #include "oat_file-inl.h"
     45 #include "runtime_callbacks.h"
     46 #include "scoped_thread_state_change-inl.h"
     47 #include "vdex_file.h"
     48 #include "well_known_classes.h"
     49 
     50 namespace art {
     51 
     52 using android::base::StringPrintf;
     53 
     54 extern "C" void art_quick_invoke_stub(ArtMethod*, uint32_t*, uint32_t, Thread*, JValue*,
     55                                       const char*);
     56 extern "C" void art_quick_invoke_static_stub(ArtMethod*, uint32_t*, uint32_t, Thread*, JValue*,
     57                                              const char*);
     58 
     59 DEFINE_RUNTIME_DEBUG_FLAG(ArtMethod, kCheckDeclaringClassState);
     60 
     61 // Enforce that we he have the right index for runtime methods.
     62 static_assert(ArtMethod::kRuntimeMethodDexMethodIndex == DexFile::kDexNoIndex,
     63               "Wrong runtime-method dex method index");
     64 
     65 ArtMethod* ArtMethod::GetCanonicalMethod(PointerSize pointer_size) {
     66   if (LIKELY(!IsDefault())) {
     67     return this;
     68   } else {
     69     mirror::Class* declaring_class = GetDeclaringClass();
     70     DCHECK(declaring_class->IsInterface());
     71     ArtMethod* ret = declaring_class->FindInterfaceMethod(declaring_class->GetDexCache(),
     72                                                           GetDexMethodIndex(),
     73                                                           pointer_size);
     74     DCHECK(ret != nullptr);
     75     return ret;
     76   }
     77 }
     78 
     79 ArtMethod* ArtMethod::GetNonObsoleteMethod() {
     80   DCHECK_EQ(kRuntimePointerSize, Runtime::Current()->GetClassLinker()->GetImagePointerSize());
     81   if (LIKELY(!IsObsolete())) {
     82     return this;
     83   } else if (IsDirect()) {
     84     return &GetDeclaringClass()->GetDirectMethodsSlice(kRuntimePointerSize)[GetMethodIndex()];
     85   } else {
     86     return GetDeclaringClass()->GetVTableEntry(GetMethodIndex(), kRuntimePointerSize);
     87   }
     88 }
     89 
     90 ArtMethod* ArtMethod::GetSingleImplementation(PointerSize pointer_size) {
     91   if (!IsAbstract()) {
     92     // A non-abstract's single implementation is itself.
     93     return this;
     94   }
     95   return reinterpret_cast<ArtMethod*>(GetDataPtrSize(pointer_size));
     96 }
     97 
     98 ArtMethod* ArtMethod::FromReflectedMethod(const ScopedObjectAccessAlreadyRunnable& soa,
     99                                           jobject jlr_method) {
    100   ObjPtr<mirror::Executable> executable = soa.Decode<mirror::Executable>(jlr_method);
    101   DCHECK(executable != nullptr);
    102   return executable->GetArtMethod();
    103 }
    104 
    105 mirror::DexCache* ArtMethod::GetObsoleteDexCache() {
    106   DCHECK(!Runtime::Current()->IsAotCompiler()) << PrettyMethod();
    107   DCHECK(IsObsolete());
    108   ObjPtr<mirror::ClassExt> ext(GetDeclaringClass()->GetExtData());
    109   CHECK(!ext.IsNull());
    110   ObjPtr<mirror::PointerArray> obsolete_methods(ext->GetObsoleteMethods());
    111   CHECK(!obsolete_methods.IsNull());
    112   DCHECK(ext->GetObsoleteDexCaches() != nullptr);
    113   int32_t len = obsolete_methods->GetLength();
    114   DCHECK_EQ(len, ext->GetObsoleteDexCaches()->GetLength());
    115   // Using kRuntimePointerSize (instead of using the image's pointer size) is fine since images
    116   // should never have obsolete methods in them so they should always be the same.
    117   PointerSize pointer_size = kRuntimePointerSize;
    118   DCHECK_EQ(kRuntimePointerSize, Runtime::Current()->GetClassLinker()->GetImagePointerSize());
    119   for (int32_t i = 0; i < len; i++) {
    120     if (this == obsolete_methods->GetElementPtrSize<ArtMethod*>(i, pointer_size)) {
    121       return ext->GetObsoleteDexCaches()->Get(i);
    122     }
    123   }
    124   LOG(FATAL) << "This method does not appear in the obsolete map of its class!";
    125   UNREACHABLE();
    126 }
    127 
    128 uint16_t ArtMethod::FindObsoleteDexClassDefIndex() {
    129   DCHECK(!Runtime::Current()->IsAotCompiler()) << PrettyMethod();
    130   DCHECK(IsObsolete());
    131   const DexFile* dex_file = GetDexFile();
    132   const dex::TypeIndex declaring_class_type = dex_file->GetMethodId(GetDexMethodIndex()).class_idx_;
    133   const DexFile::ClassDef* class_def = dex_file->FindClassDef(declaring_class_type);
    134   CHECK(class_def != nullptr);
    135   return dex_file->GetIndexForClassDef(*class_def);
    136 }
    137 
    138 mirror::String* ArtMethod::GetNameAsString(Thread* self) {
    139   CHECK(!IsProxyMethod());
    140   StackHandleScope<1> hs(self);
    141   Handle<mirror::DexCache> dex_cache(hs.NewHandle(GetDexCache()));
    142   auto* dex_file = dex_cache->GetDexFile();
    143   uint32_t dex_method_idx = GetDexMethodIndex();
    144   const DexFile::MethodId& method_id = dex_file->GetMethodId(dex_method_idx);
    145   return Runtime::Current()->GetClassLinker()->ResolveString(*dex_file, method_id.name_idx_,
    146                                                              dex_cache);
    147 }
    148 
    149 void ArtMethod::ThrowInvocationTimeError() {
    150   DCHECK(!IsInvokable());
    151   // NOTE: IsDefaultConflicting must be first since the actual method might or might not be abstract
    152   //       due to the way we select it.
    153   if (IsDefaultConflicting()) {
    154     ThrowIncompatibleClassChangeErrorForMethodConflict(this);
    155   } else {
    156     DCHECK(IsAbstract());
    157     ThrowAbstractMethodError(this);
    158   }
    159 }
    160 
    161 InvokeType ArtMethod::GetInvokeType() {
    162   // TODO: kSuper?
    163   if (IsStatic()) {
    164     return kStatic;
    165   } else if (GetDeclaringClass()->IsInterface()) {
    166     return kInterface;
    167   } else if (IsDirect()) {
    168     return kDirect;
    169   } else {
    170     return kVirtual;
    171   }
    172 }
    173 
    174 size_t ArtMethod::NumArgRegisters(const StringPiece& shorty) {
    175   CHECK_LE(1U, shorty.length());
    176   uint32_t num_registers = 0;
    177   for (size_t i = 1; i < shorty.length(); ++i) {
    178     char ch = shorty[i];
    179     if (ch == 'D' || ch == 'J') {
    180       num_registers += 2;
    181     } else {
    182       num_registers += 1;
    183     }
    184   }
    185   return num_registers;
    186 }
    187 
    188 bool ArtMethod::HasSameNameAndSignature(ArtMethod* other) {
    189   ScopedAssertNoThreadSuspension ants("HasSameNameAndSignature");
    190   const DexFile* dex_file = GetDexFile();
    191   const DexFile::MethodId& mid = dex_file->GetMethodId(GetDexMethodIndex());
    192   if (GetDexCache() == other->GetDexCache()) {
    193     const DexFile::MethodId& mid2 = dex_file->GetMethodId(other->GetDexMethodIndex());
    194     return mid.name_idx_ == mid2.name_idx_ && mid.proto_idx_ == mid2.proto_idx_;
    195   }
    196   const DexFile* dex_file2 = other->GetDexFile();
    197   const DexFile::MethodId& mid2 = dex_file2->GetMethodId(other->GetDexMethodIndex());
    198   if (!DexFileStringEquals(dex_file, mid.name_idx_, dex_file2, mid2.name_idx_)) {
    199     return false;  // Name mismatch.
    200   }
    201   return dex_file->GetMethodSignature(mid) == dex_file2->GetMethodSignature(mid2);
    202 }
    203 
    204 ArtMethod* ArtMethod::FindOverriddenMethod(PointerSize pointer_size) {
    205   if (IsStatic()) {
    206     return nullptr;
    207   }
    208   mirror::Class* declaring_class = GetDeclaringClass();
    209   mirror::Class* super_class = declaring_class->GetSuperClass();
    210   uint16_t method_index = GetMethodIndex();
    211   ArtMethod* result = nullptr;
    212   // Did this method override a super class method? If so load the result from the super class'
    213   // vtable
    214   if (super_class->HasVTable() && method_index < super_class->GetVTableLength()) {
    215     result = super_class->GetVTableEntry(method_index, pointer_size);
    216   } else {
    217     // Method didn't override superclass method so search interfaces
    218     if (IsProxyMethod()) {
    219       result = GetInterfaceMethodIfProxy(pointer_size);
    220       DCHECK(result != nullptr);
    221     } else {
    222       mirror::IfTable* iftable = GetDeclaringClass()->GetIfTable();
    223       for (size_t i = 0; i < iftable->Count() && result == nullptr; i++) {
    224         mirror::Class* interface = iftable->GetInterface(i);
    225         for (ArtMethod& interface_method : interface->GetVirtualMethods(pointer_size)) {
    226           if (HasSameNameAndSignature(interface_method.GetInterfaceMethodIfProxy(pointer_size))) {
    227             result = &interface_method;
    228             break;
    229           }
    230         }
    231       }
    232     }
    233   }
    234   DCHECK(result == nullptr ||
    235          GetInterfaceMethodIfProxy(pointer_size)->HasSameNameAndSignature(
    236              result->GetInterfaceMethodIfProxy(pointer_size)));
    237   return result;
    238 }
    239 
    240 uint32_t ArtMethod::FindDexMethodIndexInOtherDexFile(const DexFile& other_dexfile,
    241                                                      uint32_t name_and_signature_idx) {
    242   const DexFile* dexfile = GetDexFile();
    243   const uint32_t dex_method_idx = GetDexMethodIndex();
    244   const DexFile::MethodId& mid = dexfile->GetMethodId(dex_method_idx);
    245   const DexFile::MethodId& name_and_sig_mid = other_dexfile.GetMethodId(name_and_signature_idx);
    246   DCHECK_STREQ(dexfile->GetMethodName(mid), other_dexfile.GetMethodName(name_and_sig_mid));
    247   DCHECK_EQ(dexfile->GetMethodSignature(mid), other_dexfile.GetMethodSignature(name_and_sig_mid));
    248   if (dexfile == &other_dexfile) {
    249     return dex_method_idx;
    250   }
    251   const char* mid_declaring_class_descriptor = dexfile->StringByTypeIdx(mid.class_idx_);
    252   const DexFile::TypeId* other_type_id = other_dexfile.FindTypeId(mid_declaring_class_descriptor);
    253   if (other_type_id != nullptr) {
    254     const DexFile::MethodId* other_mid = other_dexfile.FindMethodId(
    255         *other_type_id, other_dexfile.GetStringId(name_and_sig_mid.name_idx_),
    256         other_dexfile.GetProtoId(name_and_sig_mid.proto_idx_));
    257     if (other_mid != nullptr) {
    258       return other_dexfile.GetIndexForMethodId(*other_mid);
    259     }
    260   }
    261   return DexFile::kDexNoIndex;
    262 }
    263 
    264 uint32_t ArtMethod::FindCatchBlock(Handle<mirror::Class> exception_type,
    265                                    uint32_t dex_pc, bool* has_no_move_exception) {
    266   const DexFile::CodeItem* code_item = GetCodeItem();
    267   // Set aside the exception while we resolve its type.
    268   Thread* self = Thread::Current();
    269   StackHandleScope<1> hs(self);
    270   Handle<mirror::Throwable> exception(hs.NewHandle(self->GetException()));
    271   self->ClearException();
    272   // Default to handler not found.
    273   uint32_t found_dex_pc = DexFile::kDexNoIndex;
    274   // Iterate over the catch handlers associated with dex_pc.
    275   for (CatchHandlerIterator it(*code_item, dex_pc); it.HasNext(); it.Next()) {
    276     dex::TypeIndex iter_type_idx = it.GetHandlerTypeIndex();
    277     // Catch all case
    278     if (!iter_type_idx.IsValid()) {
    279       found_dex_pc = it.GetHandlerAddress();
    280       break;
    281     }
    282     // Does this catch exception type apply?
    283     mirror::Class* iter_exception_type = GetClassFromTypeIndex(iter_type_idx, true /* resolve */);
    284     if (UNLIKELY(iter_exception_type == nullptr)) {
    285       // Now have a NoClassDefFoundError as exception. Ignore in case the exception class was
    286       // removed by a pro-guard like tool.
    287       // Note: this is not RI behavior. RI would have failed when loading the class.
    288       self->ClearException();
    289       // Delete any long jump context as this routine is called during a stack walk which will
    290       // release its in use context at the end.
    291       delete self->GetLongJumpContext();
    292       LOG(WARNING) << "Unresolved exception class when finding catch block: "
    293         << DescriptorToDot(GetTypeDescriptorFromTypeIdx(iter_type_idx));
    294     } else if (iter_exception_type->IsAssignableFrom(exception_type.Get())) {
    295       found_dex_pc = it.GetHandlerAddress();
    296       break;
    297     }
    298   }
    299   if (found_dex_pc != DexFile::kDexNoIndex) {
    300     const Instruction* first_catch_instr =
    301         Instruction::At(&code_item->insns_[found_dex_pc]);
    302     *has_no_move_exception = (first_catch_instr->Opcode() != Instruction::MOVE_EXCEPTION);
    303   }
    304   // Put the exception back.
    305   if (exception != nullptr) {
    306     self->SetException(exception.Get());
    307   }
    308   return found_dex_pc;
    309 }
    310 
    311 void ArtMethod::Invoke(Thread* self, uint32_t* args, uint32_t args_size, JValue* result,
    312                        const char* shorty) {
    313   if (UNLIKELY(__builtin_frame_address(0) < self->GetStackEnd())) {
    314     ThrowStackOverflowError(self);
    315     return;
    316   }
    317 
    318   if (kIsDebugBuild) {
    319     self->AssertThreadSuspensionIsAllowable();
    320     CHECK_EQ(kRunnable, self->GetState());
    321     CHECK_STREQ(GetInterfaceMethodIfProxy(kRuntimePointerSize)->GetShorty(), shorty);
    322   }
    323 
    324   // Push a transition back into managed code onto the linked list in thread.
    325   ManagedStack fragment;
    326   self->PushManagedStackFragment(&fragment);
    327 
    328   Runtime* runtime = Runtime::Current();
    329   // Call the invoke stub, passing everything as arguments.
    330   // If the runtime is not yet started or it is required by the debugger, then perform the
    331   // Invocation by the interpreter, explicitly forcing interpretation over JIT to prevent
    332   // cycling around the various JIT/Interpreter methods that handle method invocation.
    333   if (UNLIKELY(!runtime->IsStarted() || Dbg::IsForcedInterpreterNeededForCalling(self, this))) {
    334     if (IsStatic()) {
    335       art::interpreter::EnterInterpreterFromInvoke(
    336           self, this, nullptr, args, result, /*stay_in_interpreter*/ true);
    337     } else {
    338       mirror::Object* receiver =
    339           reinterpret_cast<StackReference<mirror::Object>*>(&args[0])->AsMirrorPtr();
    340       art::interpreter::EnterInterpreterFromInvoke(
    341           self, this, receiver, args + 1, result, /*stay_in_interpreter*/ true);
    342     }
    343   } else {
    344     DCHECK_EQ(runtime->GetClassLinker()->GetImagePointerSize(), kRuntimePointerSize);
    345 
    346     constexpr bool kLogInvocationStartAndReturn = false;
    347     bool have_quick_code = GetEntryPointFromQuickCompiledCode() != nullptr;
    348     if (LIKELY(have_quick_code)) {
    349       if (kLogInvocationStartAndReturn) {
    350         LOG(INFO) << StringPrintf(
    351             "Invoking '%s' quick code=%p static=%d", PrettyMethod().c_str(),
    352             GetEntryPointFromQuickCompiledCode(), static_cast<int>(IsStatic() ? 1 : 0));
    353       }
    354 
    355       // Ensure that we won't be accidentally calling quick compiled code when -Xint.
    356       if (kIsDebugBuild && runtime->GetInstrumentation()->IsForcedInterpretOnly()) {
    357         CHECK(!runtime->UseJitCompilation());
    358         const void* oat_quick_code =
    359             (IsNative() || !IsInvokable() || IsProxyMethod() || IsObsolete())
    360             ? nullptr
    361             : GetOatMethodQuickCode(runtime->GetClassLinker()->GetImagePointerSize());
    362         CHECK(oat_quick_code == nullptr || oat_quick_code != GetEntryPointFromQuickCompiledCode())
    363             << "Don't call compiled code when -Xint " << PrettyMethod();
    364       }
    365 
    366       if (!IsStatic()) {
    367         (*art_quick_invoke_stub)(this, args, args_size, self, result, shorty);
    368       } else {
    369         (*art_quick_invoke_static_stub)(this, args, args_size, self, result, shorty);
    370       }
    371       if (UNLIKELY(self->GetException() == Thread::GetDeoptimizationException())) {
    372         // Unusual case where we were running generated code and an
    373         // exception was thrown to force the activations to be removed from the
    374         // stack. Continue execution in the interpreter.
    375         self->DeoptimizeWithDeoptimizationException(result);
    376       }
    377       if (kLogInvocationStartAndReturn) {
    378         LOG(INFO) << StringPrintf("Returned '%s' quick code=%p", PrettyMethod().c_str(),
    379                                   GetEntryPointFromQuickCompiledCode());
    380       }
    381     } else {
    382       LOG(INFO) << "Not invoking '" << PrettyMethod() << "' code=null";
    383       if (result != nullptr) {
    384         result->SetJ(0);
    385       }
    386     }
    387   }
    388 
    389   // Pop transition.
    390   self->PopManagedStackFragment(fragment);
    391 }
    392 
    393 const void* ArtMethod::RegisterNative(const void* native_method, bool is_fast) {
    394   CHECK(IsNative()) << PrettyMethod();
    395   CHECK(!IsFastNative()) << PrettyMethod();
    396   CHECK(native_method != nullptr) << PrettyMethod();
    397   if (is_fast) {
    398     AddAccessFlags(kAccFastNative);
    399   }
    400   void* new_native_method = nullptr;
    401   Runtime::Current()->GetRuntimeCallbacks()->RegisterNativeMethod(this,
    402                                                                   native_method,
    403                                                                   /*out*/&new_native_method);
    404   SetEntryPointFromJni(new_native_method);
    405   return new_native_method;
    406 }
    407 
    408 void ArtMethod::UnregisterNative() {
    409   CHECK(IsNative() && !IsFastNative()) << PrettyMethod();
    410   // restore stub to lookup native pointer via dlsym
    411   SetEntryPointFromJni(GetJniDlsymLookupStub());
    412 }
    413 
    414 bool ArtMethod::IsOverridableByDefaultMethod() {
    415   return GetDeclaringClass()->IsInterface();
    416 }
    417 
    418 bool ArtMethod::IsAnnotatedWithFastNative() {
    419   return IsAnnotatedWith(WellKnownClasses::dalvik_annotation_optimization_FastNative,
    420                          DexFile::kDexVisibilityBuild,
    421                          /* lookup_in_resolved_boot_classes */ true);
    422 }
    423 
    424 bool ArtMethod::IsAnnotatedWithCriticalNative() {
    425   return IsAnnotatedWith(WellKnownClasses::dalvik_annotation_optimization_CriticalNative,
    426                          DexFile::kDexVisibilityBuild,
    427                          /* lookup_in_resolved_boot_classes */ true);
    428 }
    429 
    430 bool ArtMethod::IsAnnotatedWith(jclass klass,
    431                                 uint32_t visibility,
    432                                 bool lookup_in_resolved_boot_classes) {
    433   Thread* self = Thread::Current();
    434   ScopedObjectAccess soa(self);
    435   StackHandleScope<1> shs(self);
    436 
    437   ObjPtr<mirror::Class> annotation = soa.Decode<mirror::Class>(klass);
    438   DCHECK(annotation->IsAnnotation());
    439   Handle<mirror::Class> annotation_handle(shs.NewHandle(annotation));
    440 
    441   return annotations::IsMethodAnnotationPresent(
    442       this, annotation_handle, visibility, lookup_in_resolved_boot_classes);
    443 }
    444 
    445 static uint32_t GetOatMethodIndexFromMethodIndex(const DexFile& dex_file,
    446                                                  uint16_t class_def_idx,
    447                                                  uint32_t method_idx) {
    448   const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_idx);
    449   const uint8_t* class_data = dex_file.GetClassData(class_def);
    450   CHECK(class_data != nullptr);
    451   ClassDataItemIterator it(dex_file, class_data);
    452   it.SkipAllFields();
    453   // Process methods
    454   size_t class_def_method_index = 0;
    455   while (it.HasNextDirectMethod()) {
    456     if (it.GetMemberIndex() == method_idx) {
    457       return class_def_method_index;
    458     }
    459     class_def_method_index++;
    460     it.Next();
    461   }
    462   while (it.HasNextVirtualMethod()) {
    463     if (it.GetMemberIndex() == method_idx) {
    464       return class_def_method_index;
    465     }
    466     class_def_method_index++;
    467     it.Next();
    468   }
    469   DCHECK(!it.HasNext());
    470   LOG(FATAL) << "Failed to find method index " << method_idx << " in " << dex_file.GetLocation();
    471   UNREACHABLE();
    472 }
    473 
    474 // We use the method's DexFile and declaring class name to find the OatMethod for an obsolete
    475 // method.  This is extremely slow but we need it if we want to be able to have obsolete native
    476 // methods since we need this to find the size of its stack frames.
    477 //
    478 // NB We could (potentially) do this differently and rely on the way the transformation is applied
    479 // in order to use the entrypoint to find this information. However, for debugging reasons (most
    480 // notably making sure that new invokes of obsolete methods fail) we choose to instead get the data
    481 // directly from the dex file.
    482 static const OatFile::OatMethod FindOatMethodFromDexFileFor(ArtMethod* method, bool* found)
    483     REQUIRES_SHARED(Locks::mutator_lock_) {
    484   DCHECK(method->IsObsolete() && method->IsNative());
    485   const DexFile* dex_file = method->GetDexFile();
    486 
    487   // recreate the class_def_index from the descriptor.
    488   std::string descriptor_storage;
    489   const DexFile::TypeId* declaring_class_type_id =
    490       dex_file->FindTypeId(method->GetDeclaringClass()->GetDescriptor(&descriptor_storage));
    491   CHECK(declaring_class_type_id != nullptr);
    492   dex::TypeIndex declaring_class_type_index = dex_file->GetIndexForTypeId(*declaring_class_type_id);
    493   const DexFile::ClassDef* declaring_class_type_def =
    494       dex_file->FindClassDef(declaring_class_type_index);
    495   CHECK(declaring_class_type_def != nullptr);
    496   uint16_t declaring_class_def_index = dex_file->GetIndexForClassDef(*declaring_class_type_def);
    497 
    498   size_t oat_method_index = GetOatMethodIndexFromMethodIndex(*dex_file,
    499                                                              declaring_class_def_index,
    500                                                              method->GetDexMethodIndex());
    501 
    502   OatFile::OatClass oat_class = OatFile::FindOatClass(*dex_file,
    503                                                       declaring_class_def_index,
    504                                                       found);
    505   if (!(*found)) {
    506     return OatFile::OatMethod::Invalid();
    507   }
    508   return oat_class.GetOatMethod(oat_method_index);
    509 }
    510 
    511 static const OatFile::OatMethod FindOatMethodFor(ArtMethod* method,
    512                                                  PointerSize pointer_size,
    513                                                  bool* found)
    514     REQUIRES_SHARED(Locks::mutator_lock_) {
    515   if (UNLIKELY(method->IsObsolete())) {
    516     // We shouldn't be calling this with obsolete methods except for native obsolete methods for
    517     // which we need to use the oat method to figure out how large the quick frame is.
    518     DCHECK(method->IsNative()) << "We should only be finding the OatMethod of obsolete methods in "
    519                                << "order to allow stack walking. Other obsolete methods should "
    520                                << "never need to access this information.";
    521     DCHECK_EQ(pointer_size, kRuntimePointerSize) << "Obsolete method in compiler!";
    522     return FindOatMethodFromDexFileFor(method, found);
    523   }
    524   // Although we overwrite the trampoline of non-static methods, we may get here via the resolution
    525   // method for direct methods (or virtual methods made direct).
    526   mirror::Class* declaring_class = method->GetDeclaringClass();
    527   size_t oat_method_index;
    528   if (method->IsStatic() || method->IsDirect()) {
    529     // Simple case where the oat method index was stashed at load time.
    530     oat_method_index = method->GetMethodIndex();
    531   } else {
    532     // Compute the oat_method_index by search for its position in the declared virtual methods.
    533     oat_method_index = declaring_class->NumDirectMethods();
    534     bool found_virtual = false;
    535     for (ArtMethod& art_method : declaring_class->GetVirtualMethods(pointer_size)) {
    536       // Check method index instead of identity in case of duplicate method definitions.
    537       if (method->GetDexMethodIndex() == art_method.GetDexMethodIndex()) {
    538         found_virtual = true;
    539         break;
    540       }
    541       oat_method_index++;
    542     }
    543     CHECK(found_virtual) << "Didn't find oat method index for virtual method: "
    544                          << method->PrettyMethod();
    545   }
    546   DCHECK_EQ(oat_method_index,
    547             GetOatMethodIndexFromMethodIndex(*declaring_class->GetDexCache()->GetDexFile(),
    548                                              method->GetDeclaringClass()->GetDexClassDefIndex(),
    549                                              method->GetDexMethodIndex()));
    550   OatFile::OatClass oat_class = OatFile::FindOatClass(*declaring_class->GetDexCache()->GetDexFile(),
    551                                                       declaring_class->GetDexClassDefIndex(),
    552                                                       found);
    553   if (!(*found)) {
    554     return OatFile::OatMethod::Invalid();
    555   }
    556   return oat_class.GetOatMethod(oat_method_index);
    557 }
    558 
    559 bool ArtMethod::EqualParameters(Handle<mirror::ObjectArray<mirror::Class>> params) {
    560   auto* dex_cache = GetDexCache();
    561   auto* dex_file = dex_cache->GetDexFile();
    562   const auto& method_id = dex_file->GetMethodId(GetDexMethodIndex());
    563   const auto& proto_id = dex_file->GetMethodPrototype(method_id);
    564   const DexFile::TypeList* proto_params = dex_file->GetProtoParameters(proto_id);
    565   auto count = proto_params != nullptr ? proto_params->Size() : 0u;
    566   auto param_len = params != nullptr ? params->GetLength() : 0u;
    567   if (param_len != count) {
    568     return false;
    569   }
    570   auto* cl = Runtime::Current()->GetClassLinker();
    571   for (size_t i = 0; i < count; ++i) {
    572     auto type_idx = proto_params->GetTypeItem(i).type_idx_;
    573     auto* type = cl->ResolveType(type_idx, this);
    574     if (type == nullptr) {
    575       Thread::Current()->AssertPendingException();
    576       return false;
    577     }
    578     if (type != params->GetWithoutChecks(i)) {
    579       return false;
    580     }
    581   }
    582   return true;
    583 }
    584 
    585 const uint8_t* ArtMethod::GetQuickenedInfo(PointerSize pointer_size) {
    586   if (kIsVdexEnabled) {
    587     const DexFile& dex_file = GetDeclaringClass()->GetDexFile();
    588     const OatFile::OatDexFile* oat_dex_file = dex_file.GetOatDexFile();
    589     if (oat_dex_file == nullptr || (oat_dex_file->GetOatFile() == nullptr)) {
    590       return nullptr;
    591     }
    592     return oat_dex_file->GetOatFile()->GetVdexFile()->GetQuickenedInfoOf(
    593         dex_file, GetCodeItemOffset());
    594   } else {
    595     bool found = false;
    596     OatFile::OatMethod oat_method = FindOatMethodFor(this, pointer_size, &found);
    597     if (!found || (oat_method.GetQuickCode() != nullptr)) {
    598       return nullptr;
    599     }
    600     return oat_method.GetVmapTable();
    601   }
    602 }
    603 
    604 const OatQuickMethodHeader* ArtMethod::GetOatQuickMethodHeader(uintptr_t pc) {
    605   // Our callers should make sure they don't pass the instrumentation exit pc,
    606   // as this method does not look at the side instrumentation stack.
    607   DCHECK_NE(pc, reinterpret_cast<uintptr_t>(GetQuickInstrumentationExitPc()));
    608 
    609   if (IsRuntimeMethod()) {
    610     return nullptr;
    611   }
    612 
    613   Runtime* runtime = Runtime::Current();
    614   const void* existing_entry_point = GetEntryPointFromQuickCompiledCode();
    615   CHECK(existing_entry_point != nullptr) << PrettyMethod() << "@" << this;
    616   ClassLinker* class_linker = runtime->GetClassLinker();
    617 
    618   if (class_linker->IsQuickGenericJniStub(existing_entry_point)) {
    619     // The generic JNI does not have any method header.
    620     return nullptr;
    621   }
    622 
    623   if (existing_entry_point == GetQuickProxyInvokeHandler()) {
    624     DCHECK(IsProxyMethod() && !IsConstructor());
    625     // The proxy entry point does not have any method header.
    626     return nullptr;
    627   }
    628 
    629   // Check whether the current entry point contains this pc.
    630   if (!class_linker->IsQuickResolutionStub(existing_entry_point) &&
    631       !class_linker->IsQuickToInterpreterBridge(existing_entry_point)) {
    632     OatQuickMethodHeader* method_header =
    633         OatQuickMethodHeader::FromEntryPoint(existing_entry_point);
    634 
    635     if (method_header->Contains(pc)) {
    636       return method_header;
    637     }
    638   }
    639 
    640   // Check whether the pc is in the JIT code cache.
    641   jit::Jit* jit = runtime->GetJit();
    642   if (jit != nullptr) {
    643     jit::JitCodeCache* code_cache = jit->GetCodeCache();
    644     OatQuickMethodHeader* method_header = code_cache->LookupMethodHeader(pc, this);
    645     if (method_header != nullptr) {
    646       DCHECK(method_header->Contains(pc));
    647       return method_header;
    648     } else {
    649       DCHECK(!code_cache->ContainsPc(reinterpret_cast<const void*>(pc)))
    650           << PrettyMethod()
    651           << ", pc=" << std::hex << pc
    652           << ", entry_point=" << std::hex << reinterpret_cast<uintptr_t>(existing_entry_point)
    653           << ", copy=" << std::boolalpha << IsCopied()
    654           << ", proxy=" << std::boolalpha << IsProxyMethod();
    655     }
    656   }
    657 
    658   // The code has to be in an oat file.
    659   bool found;
    660   OatFile::OatMethod oat_method =
    661       FindOatMethodFor(this, class_linker->GetImagePointerSize(), &found);
    662   if (!found) {
    663     if (class_linker->IsQuickResolutionStub(existing_entry_point)) {
    664       // We are running the generic jni stub, but the entry point of the method has not
    665       // been updated yet.
    666       DCHECK_EQ(pc, 0u) << "Should be a downcall";
    667       DCHECK(IsNative());
    668       return nullptr;
    669     }
    670     if (existing_entry_point == GetQuickInstrumentationEntryPoint()) {
    671       // We are running the generic jni stub, but the method is being instrumented.
    672       // NB We would normally expect the pc to be zero but we can have non-zero pc's if
    673       // instrumentation is installed or removed during the call which is using the generic jni
    674       // trampoline.
    675       DCHECK(IsNative());
    676       return nullptr;
    677     }
    678     // Only for unit tests.
    679     // TODO(ngeoffray): Update these tests to pass the right pc?
    680     return OatQuickMethodHeader::FromEntryPoint(existing_entry_point);
    681   }
    682   const void* oat_entry_point = oat_method.GetQuickCode();
    683   if (oat_entry_point == nullptr || class_linker->IsQuickGenericJniStub(oat_entry_point)) {
    684     DCHECK(IsNative()) << PrettyMethod();
    685     return nullptr;
    686   }
    687 
    688   OatQuickMethodHeader* method_header = OatQuickMethodHeader::FromEntryPoint(oat_entry_point);
    689   if (pc == 0) {
    690     // This is a downcall, it can only happen for a native method.
    691     DCHECK(IsNative());
    692     return method_header;
    693   }
    694 
    695   DCHECK(method_header->Contains(pc))
    696       << PrettyMethod()
    697       << " " << std::hex << pc << " " << oat_entry_point
    698       << " " << (uintptr_t)(method_header->GetCode() + method_header->GetCodeSize());
    699   return method_header;
    700 }
    701 
    702 const void* ArtMethod::GetOatMethodQuickCode(PointerSize pointer_size) {
    703   bool found;
    704   OatFile::OatMethod oat_method = FindOatMethodFor(this, pointer_size, &found);
    705   if (found) {
    706     return oat_method.GetQuickCode();
    707   }
    708   return nullptr;
    709 }
    710 
    711 bool ArtMethod::HasAnyCompiledCode() {
    712   if (IsNative() || !IsInvokable() || IsProxyMethod()) {
    713     return false;
    714   }
    715 
    716   // Check whether the JIT has compiled it.
    717   Runtime* runtime = Runtime::Current();
    718   jit::Jit* jit = runtime->GetJit();
    719   if (jit != nullptr && jit->GetCodeCache()->ContainsMethod(this)) {
    720     return true;
    721   }
    722 
    723   // Check whether we have AOT code.
    724   return GetOatMethodQuickCode(runtime->GetClassLinker()->GetImagePointerSize()) != nullptr;
    725 }
    726 
    727 void ArtMethod::CopyFrom(ArtMethod* src, PointerSize image_pointer_size) {
    728   memcpy(reinterpret_cast<void*>(this), reinterpret_cast<const void*>(src),
    729          Size(image_pointer_size));
    730   declaring_class_ = GcRoot<mirror::Class>(const_cast<ArtMethod*>(src)->GetDeclaringClass());
    731 
    732   // If the entry point of the method we are copying from is from JIT code, we just
    733   // put the entry point of the new method to interpreter. We could set the entry point
    734   // to the JIT code, but this would require taking the JIT code cache lock to notify
    735   // it, which we do not want at this level.
    736   Runtime* runtime = Runtime::Current();
    737   if (runtime->UseJitCompilation()) {
    738     if (runtime->GetJit()->GetCodeCache()->ContainsPc(GetEntryPointFromQuickCompiledCode())) {
    739       SetEntryPointFromQuickCompiledCodePtrSize(GetQuickToInterpreterBridge(), image_pointer_size);
    740     }
    741   }
    742   // Clear the profiling info for the same reasons as the JIT code.
    743   if (!src->IsNative()) {
    744     SetProfilingInfoPtrSize(nullptr, image_pointer_size);
    745   }
    746   // Clear hotness to let the JIT properly decide when to compile this method.
    747   hotness_count_ = 0;
    748 }
    749 
    750 bool ArtMethod::IsImagePointerSize(PointerSize pointer_size) {
    751   // Hijack this function to get access to PtrSizedFieldsOffset.
    752   //
    753   // Ensure that PrtSizedFieldsOffset is correct. We rely here on usually having both 32-bit and
    754   // 64-bit builds.
    755   static_assert(std::is_standard_layout<ArtMethod>::value, "ArtMethod is not standard layout.");
    756   static_assert(
    757       (sizeof(void*) != 4) ||
    758           (offsetof(ArtMethod, ptr_sized_fields_) == PtrSizedFieldsOffset(PointerSize::k32)),
    759       "Unexpected 32-bit class layout.");
    760   static_assert(
    761       (sizeof(void*) != 8) ||
    762           (offsetof(ArtMethod, ptr_sized_fields_) == PtrSizedFieldsOffset(PointerSize::k64)),
    763       "Unexpected 64-bit class layout.");
    764 
    765   Runtime* runtime = Runtime::Current();
    766   if (runtime == nullptr) {
    767     return true;
    768   }
    769   return runtime->GetClassLinker()->GetImagePointerSize() == pointer_size;
    770 }
    771 
    772 std::string ArtMethod::PrettyMethod(ArtMethod* m, bool with_signature) {
    773   if (m == nullptr) {
    774     return "null";
    775   }
    776   return m->PrettyMethod(with_signature);
    777 }
    778 
    779 std::string ArtMethod::PrettyMethod(bool with_signature) {
    780   ArtMethod* m = this;
    781   if (!m->IsRuntimeMethod()) {
    782     m = m->GetInterfaceMethodIfProxy(Runtime::Current()->GetClassLinker()->GetImagePointerSize());
    783   }
    784   std::string result(PrettyDescriptor(m->GetDeclaringClassDescriptor()));
    785   result += '.';
    786   result += m->GetName();
    787   if (UNLIKELY(m->IsFastNative())) {
    788     result += "!";
    789   }
    790   if (with_signature) {
    791     const Signature signature = m->GetSignature();
    792     std::string sig_as_string(signature.ToString());
    793     if (signature == Signature::NoSignature()) {
    794       return result + sig_as_string;
    795     }
    796     result = PrettyReturnType(sig_as_string.c_str()) + " " + result +
    797         PrettyArguments(sig_as_string.c_str());
    798   }
    799   return result;
    800 }
    801 
    802 std::string ArtMethod::JniShortName() {
    803   return GetJniShortName(GetDeclaringClassDescriptor(), GetName());
    804 }
    805 
    806 std::string ArtMethod::JniLongName() {
    807   std::string long_name;
    808   long_name += JniShortName();
    809   long_name += "__";
    810 
    811   std::string signature(GetSignature().ToString());
    812   signature.erase(0, 1);
    813   signature.erase(signature.begin() + signature.find(')'), signature.end());
    814 
    815   long_name += MangleForJni(signature);
    816 
    817   return long_name;
    818 }
    819 
    820 // AssertSharedHeld doesn't work in GetAccessFlags, so use a NO_THREAD_SAFETY_ANALYSIS helper.
    821 // TODO: Figure out why ASSERT_SHARED_CAPABILITY doesn't work.
    822 template <ReadBarrierOption kReadBarrierOption>
    823 ALWAYS_INLINE static inline void DoGetAccessFlagsHelper(ArtMethod* method)
    824     NO_THREAD_SAFETY_ANALYSIS {
    825   CHECK(method->IsRuntimeMethod() ||
    826         method->GetDeclaringClass<kReadBarrierOption>()->IsIdxLoaded() ||
    827         method->GetDeclaringClass<kReadBarrierOption>()->IsErroneous());
    828 }
    829 
    830 template <ReadBarrierOption kReadBarrierOption> void ArtMethod::GetAccessFlagsDCheck() {
    831   if (kCheckDeclaringClassState) {
    832     Thread* self = Thread::Current();
    833     if (!Locks::mutator_lock_->IsSharedHeld(self)) {
    834       if (self->IsThreadSuspensionAllowable()) {
    835         ScopedObjectAccess soa(self);
    836         CHECK(IsRuntimeMethod() ||
    837               GetDeclaringClass<kReadBarrierOption>()->IsIdxLoaded() ||
    838               GetDeclaringClass<kReadBarrierOption>()->IsErroneous());
    839       }
    840     } else {
    841       // We cannot use SOA in this case. We might be holding the lock, but may not be in the
    842       // runnable state (e.g., during GC).
    843       Locks::mutator_lock_->AssertSharedHeld(self);
    844       DoGetAccessFlagsHelper<kReadBarrierOption>(this);
    845     }
    846   }
    847 }
    848 template void ArtMethod::GetAccessFlagsDCheck<ReadBarrierOption::kWithReadBarrier>();
    849 template void ArtMethod::GetAccessFlagsDCheck<ReadBarrierOption::kWithoutReadBarrier>();
    850 
    851 }  // namespace art
    852