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/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef ART_RUNTIME_CLASS_LINKER_INL_H_
#define ART_RUNTIME_CLASS_LINKER_INL_H_
#include "art_field.h"
#include "class_linker.h"
#include "gc_root-inl.h"
#include "gc/heap-inl.h"
#include "obj_ptr-inl.h"
#include "mirror/class_loader.h"
#include "mirror/dex_cache-inl.h"
#include "mirror/iftable.h"
#include "mirror/object_array.h"
#include "handle_scope-inl.h"
#include "scoped_thread_state_change-inl.h"
#include <atomic>
namespace art {
inline mirror::Class* ClassLinker::FindArrayClass(Thread* self,
ObjPtr<mirror::Class>* element_class) {
for (size_t i = 0; i < kFindArrayCacheSize; ++i) {
// Read the cached array class once to avoid races with other threads setting it.
ObjPtr<mirror::Class> array_class = find_array_class_cache_[i].Read();
if (array_class != nullptr && array_class->GetComponentType() == *element_class) {
return array_class.Ptr();
}
}
std::string descriptor = "[";
std::string temp;
descriptor += (*element_class)->GetDescriptor(&temp);
StackHandleScope<2> hs(Thread::Current());
Handle<mirror::ClassLoader> class_loader(hs.NewHandle((*element_class)->GetClassLoader()));
HandleWrapperObjPtr<mirror::Class> h_element_class(hs.NewHandleWrapper(element_class));
ObjPtr<mirror::Class> array_class = FindClass(self, descriptor.c_str(), class_loader);
if (array_class != nullptr) {
// Benign races in storing array class and incrementing index.
size_t victim_index = find_array_class_cache_next_victim_;
find_array_class_cache_[victim_index] = GcRoot<mirror::Class>(array_class);
find_array_class_cache_next_victim_ = (victim_index + 1) % kFindArrayCacheSize;
} else {
// We should have a NoClassDefFoundError.
self->AssertPendingException();
}
return array_class.Ptr();
}
inline ObjPtr<mirror::Class> ClassLinker::LookupResolvedType(
dex::TypeIndex type_idx,
ObjPtr<mirror::DexCache> dex_cache,
ObjPtr<mirror::ClassLoader> class_loader) {
ObjPtr<mirror::Class> type = dex_cache->GetResolvedType(type_idx);
if (type == nullptr) {
type = Runtime::Current()->GetClassLinker()->LookupResolvedType(
*dex_cache->GetDexFile(), type_idx, dex_cache, class_loader);
}
return type;
}
inline mirror::Class* ClassLinker::ResolveType(dex::TypeIndex type_idx, ArtMethod* referrer) {
Thread::PoisonObjectPointersIfDebug();
if (kIsDebugBuild) {
Thread::Current()->AssertNoPendingException();
}
ObjPtr<mirror::Class> resolved_type = referrer->GetDexCache()->GetResolvedType(type_idx);
if (UNLIKELY(resolved_type == nullptr)) {
StackHandleScope<2> hs(Thread::Current());
ObjPtr<mirror::Class> declaring_class = referrer->GetDeclaringClass();
Handle<mirror::DexCache> dex_cache(hs.NewHandle(referrer->GetDexCache()));
Handle<mirror::ClassLoader> class_loader(hs.NewHandle(declaring_class->GetClassLoader()));
const DexFile& dex_file = *dex_cache->GetDexFile();
resolved_type = ResolveType(dex_file, type_idx, dex_cache, class_loader);
}
return resolved_type.Ptr();
}
inline ArtMethod* ClassLinker::GetResolvedMethod(uint32_t method_idx, ArtMethod* referrer) {
ArtMethod* resolved_method = referrer->GetDexCacheResolvedMethod(method_idx, image_pointer_size_);
if (resolved_method == nullptr || resolved_method->IsRuntimeMethod()) {
return nullptr;
}
return resolved_method;
}
inline mirror::Class* ClassLinker::ResolveReferencedClassOfMethod(
uint32_t method_idx,
Handle<mirror::DexCache> dex_cache,
Handle<mirror::ClassLoader> class_loader) {
// NB: We cannot simply use `GetResolvedMethod(method_idx, ...)->GetDeclaringClass()`. This is
// because if we did so than an invoke-super could be incorrectly dispatched in cases where
// GetMethodId(method_idx).class_idx_ refers to a non-interface, non-direct-superclass
// (super*-class?) of the referrer and the direct superclass of the referrer contains a concrete
// implementation of the method. If this class's implementation of the method is copied from an
// interface (either miranda, default or conflict) we would incorrectly assume that is what we
// want to invoke on, instead of the 'concrete' implementation that the direct superclass
// contains.
const DexFile* dex_file = dex_cache->GetDexFile();
const DexFile::MethodId& method = dex_file->GetMethodId(method_idx);
ObjPtr<mirror::Class> resolved_type = dex_cache->GetResolvedType(method.class_idx_);
if (UNLIKELY(resolved_type == nullptr)) {
resolved_type = ResolveType(*dex_file, method.class_idx_, dex_cache, class_loader);
}
return resolved_type.Ptr();
}
template <ClassLinker::ResolveMode kResolveMode>
inline ArtMethod* ClassLinker::ResolveMethod(Thread* self,
uint32_t method_idx,
ArtMethod* referrer,
InvokeType type) {
ArtMethod* resolved_method = GetResolvedMethod(method_idx, referrer);
Thread::PoisonObjectPointersIfDebug();
if (UNLIKELY(resolved_method == nullptr)) {
ObjPtr<mirror::Class> declaring_class = referrer->GetDeclaringClass();
StackHandleScope<2> hs(self);
Handle<mirror::DexCache> h_dex_cache(hs.NewHandle(referrer->GetDexCache()));
Handle<mirror::ClassLoader> h_class_loader(hs.NewHandle(declaring_class->GetClassLoader()));
const DexFile* dex_file = h_dex_cache->GetDexFile();
resolved_method = ResolveMethod<kResolveMode>(*dex_file,
method_idx,
h_dex_cache,
h_class_loader,
referrer,
type);
}
// Note: We cannot check here to see whether we added the method to the cache. It
// might be an erroneous class, which results in it being hidden from us.
return resolved_method;
}
inline ArtField* ClassLinker::LookupResolvedField(uint32_t field_idx,
ArtMethod* referrer,
bool is_static) {
ObjPtr<mirror::DexCache> dex_cache = referrer->GetDexCache();
ArtField* field = dex_cache->GetResolvedField(field_idx, image_pointer_size_);
if (field == nullptr) {
field = LookupResolvedField(field_idx, dex_cache, referrer->GetClassLoader(), is_static);
}
return field;
}
inline ArtField* ClassLinker::ResolveField(uint32_t field_idx,
ArtMethod* referrer,
bool is_static) {
Thread::PoisonObjectPointersIfDebug();
ObjPtr<mirror::Class> declaring_class = referrer->GetDeclaringClass();
ArtField* resolved_field =
referrer->GetDexCache()->GetResolvedField(field_idx, image_pointer_size_);
if (UNLIKELY(resolved_field == nullptr)) {
StackHandleScope<2> hs(Thread::Current());
Handle<mirror::DexCache> dex_cache(hs.NewHandle(referrer->GetDexCache()));
Handle<mirror::ClassLoader> class_loader(hs.NewHandle(declaring_class->GetClassLoader()));
const DexFile& dex_file = *dex_cache->GetDexFile();
resolved_field = ResolveField(dex_file, field_idx, dex_cache, class_loader, is_static);
// Note: We cannot check here to see whether we added the field to the cache. The type
// might be an erroneous class, which results in it being hidden from us.
}
return resolved_field;
}
inline mirror::Class* ClassLinker::GetClassRoot(ClassRoot class_root) {
DCHECK(!class_roots_.IsNull());
mirror::ObjectArray<mirror::Class>* class_roots = class_roots_.Read();
ObjPtr<mirror::Class> klass = class_roots->Get(class_root);
DCHECK(klass != nullptr);
return klass.Ptr();
}
template<ReadBarrierOption kReadBarrierOption>
ArtMethod* ClassLinker::FindMethodForProxy(ObjPtr<mirror::Class> proxy_class,
ArtMethod* proxy_method) {
DCHECK(proxy_class->IsProxyClass());
DCHECK(proxy_method->IsProxyMethod());
{
Thread* const self = Thread::Current();
ReaderMutexLock mu(self, *Locks::dex_lock_);
// Locate the dex cache of the original interface/Object
for (const DexCacheData& data : dex_caches_) {
if (!self->IsJWeakCleared(data.weak_root) &&
proxy_method->HasSameDexCacheResolvedMethods(data.resolved_methods,
image_pointer_size_)) {
ObjPtr<mirror::DexCache> dex_cache =
ObjPtr<mirror::DexCache>::DownCast(self->DecodeJObject(data.weak_root));
if (dex_cache != nullptr) {
ArtMethod* resolved_method = dex_cache->GetResolvedMethod(
proxy_method->GetDexMethodIndex(), image_pointer_size_);
CHECK(resolved_method != nullptr);
return resolved_method;
}
}
}
}
LOG(FATAL) << "Didn't find dex cache for " << proxy_class->PrettyClass() << " "
<< proxy_method->PrettyMethod();
UNREACHABLE();
}
} // namespace art
#endif // ART_RUNTIME_CLASS_LINKER_INL_H_
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