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      1 /*
      2  * Copyright (C) 2012 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 #ifndef ART_RUNTIME_ENTRYPOINTS_ENTRYPOINT_UTILS_INL_H_
     18 #define ART_RUNTIME_ENTRYPOINTS_ENTRYPOINT_UTILS_INL_H_
     19 
     20 #include "entrypoint_utils.h"
     21 
     22 #include "class_linker-inl.h"
     23 #include "common_throws.h"
     24 #include "dex_file.h"
     25 #include "indirect_reference_table.h"
     26 #include "invoke_type.h"
     27 #include "jni_internal.h"
     28 #include "mirror/art_method.h"
     29 #include "mirror/array.h"
     30 #include "mirror/class-inl.h"
     31 #include "mirror/object-inl.h"
     32 #include "mirror/throwable.h"
     33 #include "handle_scope-inl.h"
     34 #include "thread.h"
     35 
     36 namespace art {
     37 
     38 // TODO: Fix no thread safety analysis when GCC can handle template specialization.
     39 template <const bool kAccessCheck>
     40 static inline mirror::Class* CheckObjectAlloc(uint32_t type_idx,
     41                                               mirror::ArtMethod* method,
     42                                               Thread* self, bool* slow_path) {
     43   mirror::Class* klass = method->GetDexCacheResolvedType<false>(type_idx);
     44   if (UNLIKELY(klass == NULL)) {
     45     klass = Runtime::Current()->GetClassLinker()->ResolveType(type_idx, method);
     46     *slow_path = true;
     47     if (klass == NULL) {
     48       DCHECK(self->IsExceptionPending());
     49       return nullptr;  // Failure
     50     } else {
     51       DCHECK(!self->IsExceptionPending());
     52     }
     53   }
     54   if (kAccessCheck) {
     55     if (UNLIKELY(!klass->IsInstantiable())) {
     56       ThrowLocation throw_location = self->GetCurrentLocationForThrow();
     57       self->ThrowNewException(throw_location, "Ljava/lang/InstantiationError;",
     58                               PrettyDescriptor(klass).c_str());
     59       *slow_path = true;
     60       return nullptr;  // Failure
     61     }
     62     mirror::Class* referrer = method->GetDeclaringClass();
     63     if (UNLIKELY(!referrer->CanAccess(klass))) {
     64       ThrowIllegalAccessErrorClass(referrer, klass);
     65       *slow_path = true;
     66       return nullptr;  // Failure
     67     }
     68   }
     69   if (UNLIKELY(!klass->IsInitialized())) {
     70     StackHandleScope<1> hs(self);
     71     Handle<mirror::Class> h_klass(hs.NewHandle(klass));
     72     // EnsureInitialized (the class initializer) might cause a GC.
     73     // may cause us to suspend meaning that another thread may try to
     74     // change the allocator while we are stuck in the entrypoints of
     75     // an old allocator. Also, the class initialization may fail. To
     76     // handle these cases we mark the slow path boolean as true so
     77     // that the caller knows to check the allocator type to see if it
     78     // has changed and to null-check the return value in case the
     79     // initialization fails.
     80     *slow_path = true;
     81     if (!Runtime::Current()->GetClassLinker()->EnsureInitialized(h_klass, true, true)) {
     82       DCHECK(self->IsExceptionPending());
     83       return nullptr;  // Failure
     84     } else {
     85       DCHECK(!self->IsExceptionPending());
     86     }
     87     return h_klass.Get();
     88   }
     89   return klass;
     90 }
     91 
     92 // TODO: Fix no thread safety analysis when annotalysis is smarter.
     93 static inline mirror::Class* CheckClassInitializedForObjectAlloc(mirror::Class* klass,
     94                                                                  Thread* self,
     95                                                                  bool* slow_path) {
     96   if (UNLIKELY(!klass->IsInitialized())) {
     97     StackHandleScope<1> hs(self);
     98     Handle<mirror::Class> h_class(hs.NewHandle(klass));
     99     // EnsureInitialized (the class initializer) might cause a GC.
    100     // may cause us to suspend meaning that another thread may try to
    101     // change the allocator while we are stuck in the entrypoints of
    102     // an old allocator. Also, the class initialization may fail. To
    103     // handle these cases we mark the slow path boolean as true so
    104     // that the caller knows to check the allocator type to see if it
    105     // has changed and to null-check the return value in case the
    106     // initialization fails.
    107     *slow_path = true;
    108     if (!Runtime::Current()->GetClassLinker()->EnsureInitialized(h_class, true, true)) {
    109       DCHECK(self->IsExceptionPending());
    110       return nullptr;  // Failure
    111     }
    112     return h_class.Get();
    113   }
    114   return klass;
    115 }
    116 
    117 // Given the context of a calling Method, use its DexCache to resolve a type to a Class. If it
    118 // cannot be resolved, throw an error. If it can, use it to create an instance.
    119 // When verification/compiler hasn't been able to verify access, optionally perform an access
    120 // check.
    121 // TODO: Fix NO_THREAD_SAFETY_ANALYSIS when GCC is smarter.
    122 template <bool kAccessCheck, bool kInstrumented>
    123 static inline mirror::Object* AllocObjectFromCode(uint32_t type_idx,
    124                                                   mirror::ArtMethod* method,
    125                                                   Thread* self,
    126                                                   gc::AllocatorType allocator_type) {
    127   bool slow_path = false;
    128   mirror::Class* klass = CheckObjectAlloc<kAccessCheck>(type_idx, method, self, &slow_path);
    129   if (UNLIKELY(slow_path)) {
    130     if (klass == nullptr) {
    131       return nullptr;
    132     }
    133     return klass->Alloc<kInstrumented>(self, Runtime::Current()->GetHeap()->GetCurrentAllocator());
    134   }
    135   DCHECK(klass != nullptr);
    136   return klass->Alloc<kInstrumented>(self, allocator_type);
    137 }
    138 
    139 // Given the context of a calling Method and a resolved class, create an instance.
    140 // TODO: Fix NO_THREAD_SAFETY_ANALYSIS when GCC is smarter.
    141 template <bool kInstrumented>
    142 static inline mirror::Object* AllocObjectFromCodeResolved(mirror::Class* klass,
    143                                                           mirror::ArtMethod* method,
    144                                                           Thread* self,
    145                                                           gc::AllocatorType allocator_type) {
    146   DCHECK(klass != nullptr);
    147   bool slow_path = false;
    148   klass = CheckClassInitializedForObjectAlloc(klass, self, &slow_path);
    149   if (UNLIKELY(slow_path)) {
    150     if (klass == nullptr) {
    151       return nullptr;
    152     }
    153     gc::Heap* heap = Runtime::Current()->GetHeap();
    154     // Pass in false since the object can not be finalizable.
    155     return klass->Alloc<kInstrumented, false>(self, heap->GetCurrentAllocator());
    156   }
    157   // Pass in false since the object can not be finalizable.
    158   return klass->Alloc<kInstrumented, false>(self, allocator_type);
    159 }
    160 
    161 // Given the context of a calling Method and an initialized class, create an instance.
    162 // TODO: Fix NO_THREAD_SAFETY_ANALYSIS when GCC is smarter.
    163 template <bool kInstrumented>
    164 static inline mirror::Object* AllocObjectFromCodeInitialized(mirror::Class* klass,
    165                                                              mirror::ArtMethod* method,
    166                                                              Thread* self,
    167                                                              gc::AllocatorType allocator_type) {
    168   DCHECK(klass != nullptr);
    169   // Pass in false since the object can not be finalizable.
    170   return klass->Alloc<kInstrumented, false>(self, allocator_type);
    171 }
    172 
    173 
    174 // TODO: Fix no thread safety analysis when GCC can handle template specialization.
    175 template <bool kAccessCheck>
    176 static inline mirror::Class* CheckArrayAlloc(uint32_t type_idx,
    177                                              mirror::ArtMethod* method,
    178                                              int32_t component_count,
    179                                              bool* slow_path) {
    180   if (UNLIKELY(component_count < 0)) {
    181     ThrowNegativeArraySizeException(component_count);
    182     *slow_path = true;
    183     return nullptr;  // Failure
    184   }
    185   mirror::Class* klass = method->GetDexCacheResolvedType<false>(type_idx);
    186   if (UNLIKELY(klass == nullptr)) {  // Not in dex cache so try to resolve
    187     klass = Runtime::Current()->GetClassLinker()->ResolveType(type_idx, method);
    188     *slow_path = true;
    189     if (klass == nullptr) {  // Error
    190       DCHECK(Thread::Current()->IsExceptionPending());
    191       return nullptr;  // Failure
    192     }
    193     CHECK(klass->IsArrayClass()) << PrettyClass(klass);
    194   }
    195   if (kAccessCheck) {
    196     mirror::Class* referrer = method->GetDeclaringClass();
    197     if (UNLIKELY(!referrer->CanAccess(klass))) {
    198       ThrowIllegalAccessErrorClass(referrer, klass);
    199       *slow_path = true;
    200       return nullptr;  // Failure
    201     }
    202   }
    203   return klass;
    204 }
    205 
    206 // Given the context of a calling Method, use its DexCache to resolve a type to an array Class. If
    207 // it cannot be resolved, throw an error. If it can, use it to create an array.
    208 // When verification/compiler hasn't been able to verify access, optionally perform an access
    209 // check.
    210 // TODO: Fix no thread safety analysis when GCC can handle template specialization.
    211 template <bool kAccessCheck, bool kInstrumented>
    212 static inline mirror::Array* AllocArrayFromCode(uint32_t type_idx,
    213                                                 mirror::ArtMethod* method,
    214                                                 int32_t component_count,
    215                                                 Thread* self,
    216                                                 gc::AllocatorType allocator_type) {
    217   bool slow_path = false;
    218   mirror::Class* klass = CheckArrayAlloc<kAccessCheck>(type_idx, method, component_count,
    219                                                        &slow_path);
    220   if (UNLIKELY(slow_path)) {
    221     if (klass == nullptr) {
    222       return nullptr;
    223     }
    224     gc::Heap* heap = Runtime::Current()->GetHeap();
    225     return mirror::Array::Alloc<kInstrumented>(self, klass, component_count,
    226                                                klass->GetComponentSize(),
    227                                                heap->GetCurrentAllocator());
    228   }
    229   return mirror::Array::Alloc<kInstrumented>(self, klass, component_count,
    230                                              klass->GetComponentSize(), allocator_type);
    231 }
    232 
    233 template <bool kAccessCheck, bool kInstrumented>
    234 static inline mirror::Array* AllocArrayFromCodeResolved(mirror::Class* klass,
    235                                                         mirror::ArtMethod* method,
    236                                                         int32_t component_count,
    237                                                         Thread* self,
    238                                                         gc::AllocatorType allocator_type) {
    239   DCHECK(klass != nullptr);
    240   if (UNLIKELY(component_count < 0)) {
    241     ThrowNegativeArraySizeException(component_count);
    242     return nullptr;  // Failure
    243   }
    244   if (kAccessCheck) {
    245     mirror::Class* referrer = method->GetDeclaringClass();
    246     if (UNLIKELY(!referrer->CanAccess(klass))) {
    247       ThrowIllegalAccessErrorClass(referrer, klass);
    248       return nullptr;  // Failure
    249     }
    250   }
    251   // No need to retry a slow-path allocation as the above code won't cause a GC or thread
    252   // suspension.
    253   return mirror::Array::Alloc<kInstrumented>(self, klass, component_count,
    254                                              klass->GetComponentSize(), allocator_type);
    255 }
    256 
    257 template<FindFieldType type, bool access_check>
    258 static inline mirror::ArtField* FindFieldFromCode(uint32_t field_idx, mirror::ArtMethod* referrer,
    259                                                   Thread* self, size_t expected_size) {
    260   bool is_primitive;
    261   bool is_set;
    262   bool is_static;
    263   switch (type) {
    264     case InstanceObjectRead:     is_primitive = false; is_set = false; is_static = false; break;
    265     case InstanceObjectWrite:    is_primitive = false; is_set = true;  is_static = false; break;
    266     case InstancePrimitiveRead:  is_primitive = true;  is_set = false; is_static = false; break;
    267     case InstancePrimitiveWrite: is_primitive = true;  is_set = true;  is_static = false; break;
    268     case StaticObjectRead:       is_primitive = false; is_set = false; is_static = true;  break;
    269     case StaticObjectWrite:      is_primitive = false; is_set = true;  is_static = true;  break;
    270     case StaticPrimitiveRead:    is_primitive = true;  is_set = false; is_static = true;  break;
    271     case StaticPrimitiveWrite:   // Keep GCC happy by having a default handler, fall-through.
    272     default:                     is_primitive = true;  is_set = true;  is_static = true;  break;
    273   }
    274   ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
    275   mirror::ArtField* resolved_field = class_linker->ResolveField(field_idx, referrer, is_static);
    276   if (UNLIKELY(resolved_field == nullptr)) {
    277     DCHECK(self->IsExceptionPending());  // Throw exception and unwind.
    278     return nullptr;  // Failure.
    279   }
    280   mirror::Class* fields_class = resolved_field->GetDeclaringClass();
    281   if (access_check) {
    282     if (UNLIKELY(resolved_field->IsStatic() != is_static)) {
    283       ThrowIncompatibleClassChangeErrorField(resolved_field, is_static, referrer);
    284       return nullptr;
    285     }
    286     mirror::Class* referring_class = referrer->GetDeclaringClass();
    287     if (UNLIKELY(!referring_class->CheckResolvedFieldAccess(fields_class, resolved_field,
    288                                                             field_idx))) {
    289       DCHECK(self->IsExceptionPending());  // Throw exception and unwind.
    290       return nullptr;  // Failure.
    291     }
    292     if (UNLIKELY(is_set && resolved_field->IsFinal() && (fields_class != referring_class))) {
    293       ThrowIllegalAccessErrorFinalField(referrer, resolved_field);
    294       return nullptr;  // Failure.
    295     } else {
    296       if (UNLIKELY(resolved_field->IsPrimitiveType() != is_primitive ||
    297                    resolved_field->FieldSize() != expected_size)) {
    298         ThrowLocation throw_location = self->GetCurrentLocationForThrow();
    299         DCHECK(throw_location.GetMethod() == referrer);
    300         self->ThrowNewExceptionF(throw_location, "Ljava/lang/NoSuchFieldError;",
    301                                  "Attempted read of %zd-bit %s on field '%s'",
    302                                  expected_size * (32 / sizeof(int32_t)),
    303                                  is_primitive ? "primitive" : "non-primitive",
    304                                  PrettyField(resolved_field, true).c_str());
    305         return nullptr;  // Failure.
    306       }
    307     }
    308   }
    309   if (!is_static) {
    310     // instance fields must be being accessed on an initialized class
    311     return resolved_field;
    312   } else {
    313     // If the class is initialized we're done.
    314     if (LIKELY(fields_class->IsInitialized())) {
    315       return resolved_field;
    316     } else {
    317       StackHandleScope<1> hs(self);
    318       Handle<mirror::Class> h_class(hs.NewHandle(fields_class));
    319       if (LIKELY(class_linker->EnsureInitialized(h_class, true, true))) {
    320         // Otherwise let's ensure the class is initialized before resolving the field.
    321         return resolved_field;
    322       }
    323       DCHECK(self->IsExceptionPending());  // Throw exception and unwind
    324       return nullptr;  // Failure.
    325     }
    326   }
    327 }
    328 
    329 // Explicit template declarations of FindFieldFromCode for all field access types.
    330 #define EXPLICIT_FIND_FIELD_FROM_CODE_TEMPLATE_DECL(_type, _access_check) \
    331 template SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) ALWAYS_INLINE \
    332 mirror::ArtField* FindFieldFromCode<_type, _access_check>(uint32_t field_idx, \
    333                                                           mirror::ArtMethod* referrer, \
    334                                                           Thread* self, size_t expected_size) \
    335 
    336 #define EXPLICIT_FIND_FIELD_FROM_CODE_TYPED_TEMPLATE_DECL(_type) \
    337     EXPLICIT_FIND_FIELD_FROM_CODE_TEMPLATE_DECL(_type, false); \
    338     EXPLICIT_FIND_FIELD_FROM_CODE_TEMPLATE_DECL(_type, true)
    339 
    340 EXPLICIT_FIND_FIELD_FROM_CODE_TYPED_TEMPLATE_DECL(InstanceObjectRead);
    341 EXPLICIT_FIND_FIELD_FROM_CODE_TYPED_TEMPLATE_DECL(InstanceObjectWrite);
    342 EXPLICIT_FIND_FIELD_FROM_CODE_TYPED_TEMPLATE_DECL(InstancePrimitiveRead);
    343 EXPLICIT_FIND_FIELD_FROM_CODE_TYPED_TEMPLATE_DECL(InstancePrimitiveWrite);
    344 EXPLICIT_FIND_FIELD_FROM_CODE_TYPED_TEMPLATE_DECL(StaticObjectRead);
    345 EXPLICIT_FIND_FIELD_FROM_CODE_TYPED_TEMPLATE_DECL(StaticObjectWrite);
    346 EXPLICIT_FIND_FIELD_FROM_CODE_TYPED_TEMPLATE_DECL(StaticPrimitiveRead);
    347 EXPLICIT_FIND_FIELD_FROM_CODE_TYPED_TEMPLATE_DECL(StaticPrimitiveWrite);
    348 
    349 #undef EXPLICIT_FIND_FIELD_FROM_CODE_TYPED_TEMPLATE_DECL
    350 #undef EXPLICIT_FIND_FIELD_FROM_CODE_TEMPLATE_DECL
    351 
    352 template<InvokeType type, bool access_check>
    353 static inline mirror::ArtMethod* FindMethodFromCode(uint32_t method_idx,
    354                                                     mirror::Object** this_object,
    355                                                     mirror::ArtMethod** referrer, Thread* self) {
    356   ClassLinker* const class_linker = Runtime::Current()->GetClassLinker();
    357   mirror::ArtMethod* resolved_method = class_linker->GetResolvedMethod(method_idx, *referrer, type);
    358   if (resolved_method == nullptr) {
    359     StackHandleScope<1> hs(self);
    360     mirror::Object* null_this = nullptr;
    361     HandleWrapper<mirror::Object> h_this(
    362         hs.NewHandleWrapper(type == kStatic ? &null_this : this_object));
    363     resolved_method = class_linker->ResolveMethod(self, method_idx, referrer, type);
    364   }
    365   if (UNLIKELY(resolved_method == nullptr)) {
    366     DCHECK(self->IsExceptionPending());  // Throw exception and unwind.
    367     return nullptr;  // Failure.
    368   } else if (UNLIKELY(*this_object == nullptr && type != kStatic)) {
    369     // Maintain interpreter-like semantics where NullPointerException is thrown
    370     // after potential NoSuchMethodError from class linker.
    371     ThrowLocation throw_location = self->GetCurrentLocationForThrow();
    372     DCHECK_EQ(*referrer, throw_location.GetMethod());
    373     ThrowNullPointerExceptionForMethodAccess(throw_location, method_idx, type);
    374     return nullptr;  // Failure.
    375   } else if (access_check) {
    376     // Incompatible class change should have been handled in resolve method.
    377     if (UNLIKELY(resolved_method->CheckIncompatibleClassChange(type))) {
    378       ThrowIncompatibleClassChangeError(type, resolved_method->GetInvokeType(), resolved_method,
    379                                         *referrer);
    380       return nullptr;  // Failure.
    381     }
    382     mirror::Class* methods_class = resolved_method->GetDeclaringClass();
    383     mirror::Class* referring_class = (*referrer)->GetDeclaringClass();
    384     bool can_access_resolved_method =
    385         referring_class->CheckResolvedMethodAccess<type>(methods_class, resolved_method,
    386                                                          method_idx);
    387     if (UNLIKELY(!can_access_resolved_method)) {
    388       DCHECK(self->IsExceptionPending());  // Throw exception and unwind.
    389       return nullptr;  // Failure.
    390     }
    391   }
    392   switch (type) {
    393     case kStatic:
    394     case kDirect:
    395       return resolved_method;
    396     case kVirtual: {
    397       mirror::Class* klass = (*this_object)->GetClass();
    398       uint16_t vtable_index = resolved_method->GetMethodIndex();
    399       if (access_check &&
    400           (!klass->HasVTable() ||
    401            vtable_index >= static_cast<uint32_t>(klass->GetVTableLength()))) {
    402         // Behavior to agree with that of the verifier.
    403         ThrowNoSuchMethodError(type, resolved_method->GetDeclaringClass(),
    404                                resolved_method->GetName(), resolved_method->GetSignature());
    405         return nullptr;  // Failure.
    406       }
    407       DCHECK(klass->HasVTable()) << PrettyClass(klass);
    408       return klass->GetVTableEntry(vtable_index);
    409     }
    410     case kSuper: {
    411       mirror::Class* super_class = (*referrer)->GetDeclaringClass()->GetSuperClass();
    412       uint16_t vtable_index = resolved_method->GetMethodIndex();
    413       if (access_check) {
    414         // Check existence of super class.
    415         if (super_class == nullptr || !super_class->HasVTable() ||
    416             vtable_index >= static_cast<uint32_t>(super_class->GetVTableLength())) {
    417           // Behavior to agree with that of the verifier.
    418           ThrowNoSuchMethodError(type, resolved_method->GetDeclaringClass(),
    419                                  resolved_method->GetName(), resolved_method->GetSignature());
    420           return nullptr;  // Failure.
    421         }
    422       } else {
    423         // Super class must exist.
    424         DCHECK(super_class != nullptr);
    425       }
    426       DCHECK(super_class->HasVTable());
    427       return super_class->GetVTableEntry(vtable_index);
    428     }
    429     case kInterface: {
    430       uint32_t imt_index = resolved_method->GetDexMethodIndex() % mirror::Class::kImtSize;
    431       mirror::ArtMethod* imt_method = (*this_object)->GetClass()->GetEmbeddedImTableEntry(imt_index);
    432       if (!imt_method->IsImtConflictMethod()) {
    433         return imt_method;
    434       } else {
    435         mirror::ArtMethod* interface_method =
    436             (*this_object)->GetClass()->FindVirtualMethodForInterface(resolved_method);
    437         if (UNLIKELY(interface_method == nullptr)) {
    438           ThrowIncompatibleClassChangeErrorClassForInterfaceDispatch(resolved_method,
    439                                                                      *this_object, *referrer);
    440           return nullptr;  // Failure.
    441         }
    442         return interface_method;
    443       }
    444     }
    445     default:
    446       LOG(FATAL) << "Unknown invoke type " << type;
    447       return nullptr;  // Failure.
    448   }
    449 }
    450 
    451 // Explicit template declarations of FindMethodFromCode for all invoke types.
    452 #define EXPLICIT_FIND_METHOD_FROM_CODE_TEMPLATE_DECL(_type, _access_check)                 \
    453   template SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) ALWAYS_INLINE                       \
    454   mirror::ArtMethod* FindMethodFromCode<_type, _access_check>(uint32_t method_idx,         \
    455                                                               mirror::Object** this_object, \
    456                                                               mirror::ArtMethod** referrer, \
    457                                                               Thread* self)
    458 #define EXPLICIT_FIND_METHOD_FROM_CODE_TYPED_TEMPLATE_DECL(_type) \
    459     EXPLICIT_FIND_METHOD_FROM_CODE_TEMPLATE_DECL(_type, false);   \
    460     EXPLICIT_FIND_METHOD_FROM_CODE_TEMPLATE_DECL(_type, true)
    461 
    462 EXPLICIT_FIND_METHOD_FROM_CODE_TYPED_TEMPLATE_DECL(kStatic);
    463 EXPLICIT_FIND_METHOD_FROM_CODE_TYPED_TEMPLATE_DECL(kDirect);
    464 EXPLICIT_FIND_METHOD_FROM_CODE_TYPED_TEMPLATE_DECL(kVirtual);
    465 EXPLICIT_FIND_METHOD_FROM_CODE_TYPED_TEMPLATE_DECL(kSuper);
    466 EXPLICIT_FIND_METHOD_FROM_CODE_TYPED_TEMPLATE_DECL(kInterface);
    467 
    468 #undef EXPLICIT_FIND_METHOD_FROM_CODE_TYPED_TEMPLATE_DECL
    469 #undef EXPLICIT_FIND_METHOD_FROM_CODE_TEMPLATE_DECL
    470 
    471 // Fast path field resolution that can't initialize classes or throw exceptions.
    472 static inline mirror::ArtField* FindFieldFast(uint32_t field_idx,
    473                                               mirror::ArtMethod* referrer,
    474                                               FindFieldType type, size_t expected_size) {
    475   mirror::ArtField* resolved_field =
    476       referrer->GetDeclaringClass()->GetDexCache()->GetResolvedField(field_idx);
    477   if (UNLIKELY(resolved_field == nullptr)) {
    478     return nullptr;
    479   }
    480   // Check for incompatible class change.
    481   bool is_primitive;
    482   bool is_set;
    483   bool is_static;
    484   switch (type) {
    485     case InstanceObjectRead:     is_primitive = false; is_set = false; is_static = false; break;
    486     case InstanceObjectWrite:    is_primitive = false; is_set = true;  is_static = false; break;
    487     case InstancePrimitiveRead:  is_primitive = true;  is_set = false; is_static = false; break;
    488     case InstancePrimitiveWrite: is_primitive = true;  is_set = true;  is_static = false; break;
    489     case StaticObjectRead:       is_primitive = false; is_set = false; is_static = true;  break;
    490     case StaticObjectWrite:      is_primitive = false; is_set = true;  is_static = true;  break;
    491     case StaticPrimitiveRead:    is_primitive = true;  is_set = false; is_static = true;  break;
    492     case StaticPrimitiveWrite:   is_primitive = true;  is_set = true;  is_static = true;  break;
    493     default:
    494       LOG(FATAL) << "UNREACHABLE";  // Assignment below to avoid GCC warnings.
    495       is_primitive = true;
    496       is_set = true;
    497       is_static = true;
    498       break;
    499   }
    500   if (UNLIKELY(resolved_field->IsStatic() != is_static)) {
    501     // Incompatible class change.
    502     return nullptr;
    503   }
    504   mirror::Class* fields_class = resolved_field->GetDeclaringClass();
    505   if (is_static) {
    506     // Check class is initialized else fail so that we can contend to initialize the class with
    507     // other threads that may be racing to do this.
    508     if (UNLIKELY(!fields_class->IsInitialized())) {
    509       return nullptr;
    510     }
    511   }
    512   mirror::Class* referring_class = referrer->GetDeclaringClass();
    513   if (UNLIKELY(!referring_class->CanAccess(fields_class) ||
    514                !referring_class->CanAccessMember(fields_class,
    515                                                  resolved_field->GetAccessFlags()) ||
    516                (is_set && resolved_field->IsFinal() && (fields_class != referring_class)))) {
    517     // Illegal access.
    518     return nullptr;
    519   }
    520   if (UNLIKELY(resolved_field->IsPrimitiveType() != is_primitive ||
    521                resolved_field->FieldSize() != expected_size)) {
    522     return nullptr;
    523   }
    524   return resolved_field;
    525 }
    526 
    527 // Fast path method resolution that can't throw exceptions.
    528 static inline mirror::ArtMethod* FindMethodFast(uint32_t method_idx,
    529                                                 mirror::Object* this_object,
    530                                                 mirror::ArtMethod* referrer,
    531                                                 bool access_check, InvokeType type) {
    532   bool is_direct = type == kStatic || type == kDirect;
    533   if (UNLIKELY(this_object == NULL && !is_direct)) {
    534     return NULL;
    535   }
    536   mirror::ArtMethod* resolved_method =
    537       referrer->GetDeclaringClass()->GetDexCache()->GetResolvedMethod(method_idx);
    538   if (UNLIKELY(resolved_method == NULL)) {
    539     return NULL;
    540   }
    541   if (access_check) {
    542     // Check for incompatible class change errors and access.
    543     bool icce = resolved_method->CheckIncompatibleClassChange(type);
    544     if (UNLIKELY(icce)) {
    545       return NULL;
    546     }
    547     mirror::Class* methods_class = resolved_method->GetDeclaringClass();
    548     mirror::Class* referring_class = referrer->GetDeclaringClass();
    549     if (UNLIKELY(!referring_class->CanAccess(methods_class) ||
    550                  !referring_class->CanAccessMember(methods_class,
    551                                                    resolved_method->GetAccessFlags()))) {
    552       // Potential illegal access, may need to refine the method's class.
    553       return NULL;
    554     }
    555   }
    556   if (type == kInterface) {  // Most common form of slow path dispatch.
    557     return this_object->GetClass()->FindVirtualMethodForInterface(resolved_method);
    558   } else if (is_direct) {
    559     return resolved_method;
    560   } else if (type == kSuper) {
    561     return referrer->GetDeclaringClass()->GetSuperClass()
    562                    ->GetVTableEntry(resolved_method->GetMethodIndex());
    563   } else {
    564     DCHECK(type == kVirtual);
    565     return this_object->GetClass()->GetVTableEntry(resolved_method->GetMethodIndex());
    566   }
    567 }
    568 
    569 static inline mirror::Class* ResolveVerifyAndClinit(uint32_t type_idx,
    570                                                     mirror::ArtMethod* referrer,
    571                                                     Thread* self, bool can_run_clinit,
    572                                                     bool verify_access) {
    573   ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
    574   mirror::Class* klass = class_linker->ResolveType(type_idx, referrer);
    575   if (UNLIKELY(klass == nullptr)) {
    576     CHECK(self->IsExceptionPending());
    577     return nullptr;  // Failure - Indicate to caller to deliver exception
    578   }
    579   // Perform access check if necessary.
    580   mirror::Class* referring_class = referrer->GetDeclaringClass();
    581   if (verify_access && UNLIKELY(!referring_class->CanAccess(klass))) {
    582     ThrowIllegalAccessErrorClass(referring_class, klass);
    583     return nullptr;  // Failure - Indicate to caller to deliver exception
    584   }
    585   // If we're just implementing const-class, we shouldn't call <clinit>.
    586   if (!can_run_clinit) {
    587     return klass;
    588   }
    589   // If we are the <clinit> of this class, just return our storage.
    590   //
    591   // Do not set the DexCache InitializedStaticStorage, since that implies <clinit> has finished
    592   // running.
    593   if (klass == referring_class && referrer->IsConstructor() && referrer->IsStatic()) {
    594     return klass;
    595   }
    596   StackHandleScope<1> hs(self);
    597   Handle<mirror::Class> h_class(hs.NewHandle(klass));
    598   if (!class_linker->EnsureInitialized(h_class, true, true)) {
    599     CHECK(self->IsExceptionPending());
    600     return nullptr;  // Failure - Indicate to caller to deliver exception
    601   }
    602   return h_class.Get();
    603 }
    604 
    605 static inline mirror::String* ResolveStringFromCode(mirror::ArtMethod* referrer,
    606                                                     uint32_t string_idx) {
    607   ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
    608   return class_linker->ResolveString(string_idx, referrer);
    609 }
    610 
    611 static inline void UnlockJniSynchronizedMethod(jobject locked, Thread* self) {
    612   // Save any pending exception over monitor exit call.
    613   mirror::Throwable* saved_exception = NULL;
    614   ThrowLocation saved_throw_location;
    615   bool is_exception_reported = self->IsExceptionReportedToInstrumentation();
    616   if (UNLIKELY(self->IsExceptionPending())) {
    617     saved_exception = self->GetException(&saved_throw_location);
    618     self->ClearException();
    619   }
    620   // Decode locked object and unlock, before popping local references.
    621   self->DecodeJObject(locked)->MonitorExit(self);
    622   if (UNLIKELY(self->IsExceptionPending())) {
    623     LOG(FATAL) << "Synchronized JNI code returning with an exception:\n"
    624         << saved_exception->Dump()
    625         << "\nEncountered second exception during implicit MonitorExit:\n"
    626         << self->GetException(NULL)->Dump();
    627   }
    628   // Restore pending exception.
    629   if (saved_exception != NULL) {
    630     self->SetException(saved_throw_location, saved_exception);
    631     self->SetExceptionReportedToInstrumentation(is_exception_reported);
    632   }
    633 }
    634 
    635 static inline void CheckSuspend(Thread* thread) {
    636   for (;;) {
    637     if (thread->ReadFlag(kCheckpointRequest)) {
    638       thread->RunCheckpointFunction();
    639     } else if (thread->ReadFlag(kSuspendRequest)) {
    640       thread->FullSuspendCheck();
    641     } else {
    642       break;
    643     }
    644   }
    645 }
    646 
    647 template <typename INT_TYPE, typename FLOAT_TYPE>
    648 static inline INT_TYPE art_float_to_integral(FLOAT_TYPE f) {
    649   const INT_TYPE kMaxInt = static_cast<INT_TYPE>(std::numeric_limits<INT_TYPE>::max());
    650   const INT_TYPE kMinInt = static_cast<INT_TYPE>(std::numeric_limits<INT_TYPE>::min());
    651   const FLOAT_TYPE kMaxIntAsFloat = static_cast<FLOAT_TYPE>(kMaxInt);
    652   const FLOAT_TYPE kMinIntAsFloat = static_cast<FLOAT_TYPE>(kMinInt);
    653   if (LIKELY(f > kMinIntAsFloat)) {
    654      if (LIKELY(f < kMaxIntAsFloat)) {
    655        return static_cast<INT_TYPE>(f);
    656      } else {
    657        return kMaxInt;
    658      }
    659   } else {
    660     return (f != f) ? 0 : kMinInt;  // f != f implies NaN
    661   }
    662 }
    663 
    664 }  // namespace art
    665 
    666 #endif  // ART_RUNTIME_ENTRYPOINTS_ENTRYPOINT_UTILS_INL_H_
    667