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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.
*/
#include "class.h"
#include <unordered_set>
#include <string_view>
#include "android-base/macros.h"
#include "android-base/stringprintf.h"
#include "array-inl.h"
#include "art_field-inl.h"
#include "art_method-inl.h"
#include "base/enums.h"
#include "base/logging.h" // For VLOG.
#include "base/utils.h"
#include "class-inl.h"
#include "class_ext-inl.h"
#include "class_linker-inl.h"
#include "class_loader.h"
#include "class_root-inl.h"
#include "dex/descriptors_names.h"
#include "dex/dex_file-inl.h"
#include "dex/dex_file_annotations.h"
#include "dex/signature-inl.h"
#include "dex_cache-inl.h"
#include "gc/accounting/card_table-inl.h"
#include "gc/heap-inl.h"
#include "handle_scope-inl.h"
#include "hidden_api.h"
#include "jni_id_type.h"
#include "subtype_check.h"
#include "method.h"
#include "object-inl.h"
#include "object-refvisitor-inl.h"
#include "object_array-inl.h"
#include "object_lock.h"
#include "string-inl.h"
#include "runtime.h"
#include "thread.h"
#include "throwable.h"
#include "well_known_classes.h"
namespace art {
// TODO: move to own CC file?
constexpr size_t BitString::kBitSizeAtPosition[BitString::kCapacity];
constexpr size_t BitString::kCapacity;
namespace mirror {
using android::base::StringPrintf;
bool Class::IsMirrored() {
if (LIKELY(!IsBootStrapClassLoaded())) {
return false;
}
if (IsPrimitive() || IsArrayClass() || IsProxyClass()) {
return true;
}
std::string name_storage;
const std::string_view name(this->GetDescriptor(&name_storage));
return IsMirroredDescriptor(name);
}
ObjPtr<mirror::Class> Class::GetPrimitiveClass(ObjPtr<mirror::String> name) {
const char* expected_name = nullptr;
ClassRoot class_root = ClassRoot::kJavaLangObject; // Invalid.
if (name != nullptr && name->GetLength() >= 2) {
// Perfect hash for the expected values: from the second letters of the primitive types,
// only 'y' has the bit 0x10 set, so use it to change 'b' to 'B'.
char hash = name->CharAt(0) ^ ((name->CharAt(1) & 0x10) << 1);
switch (hash) {
case 'b': expected_name = "boolean"; class_root = ClassRoot::kPrimitiveBoolean; break;
case 'B': expected_name = "byte"; class_root = ClassRoot::kPrimitiveByte; break;
case 'c': expected_name = "char"; class_root = ClassRoot::kPrimitiveChar; break;
case 'd': expected_name = "double"; class_root = ClassRoot::kPrimitiveDouble; break;
case 'f': expected_name = "float"; class_root = ClassRoot::kPrimitiveFloat; break;
case 'i': expected_name = "int"; class_root = ClassRoot::kPrimitiveInt; break;
case 'l': expected_name = "long"; class_root = ClassRoot::kPrimitiveLong; break;
case 's': expected_name = "short"; class_root = ClassRoot::kPrimitiveShort; break;
case 'v': expected_name = "void"; class_root = ClassRoot::kPrimitiveVoid; break;
default: break;
}
}
if (expected_name != nullptr && name->Equals(expected_name)) {
ObjPtr<mirror::Class> klass = GetClassRoot(class_root);
DCHECK(klass != nullptr);
return klass;
} else {
Thread* self = Thread::Current();
if (name == nullptr) {
// Note: ThrowNullPointerException() requires a message which we deliberately want to omit.
self->ThrowNewException("Ljava/lang/NullPointerException;", /* msg= */ nullptr);
} else {
self->ThrowNewException("Ljava/lang/ClassNotFoundException;", name->ToModifiedUtf8().c_str());
}
return nullptr;
}
}
ObjPtr<ClassExt> Class::EnsureExtDataPresent(Handle<Class> h_this, Thread* self) {
ObjPtr<ClassExt> existing(h_this->GetExtData());
if (!existing.IsNull()) {
return existing;
}
StackHandleScope<2> hs(self);
// Clear exception so we can allocate.
Handle<Throwable> throwable(hs.NewHandle(self->GetException()));
self->ClearException();
// Allocate the ClassExt
Handle<ClassExt> new_ext(hs.NewHandle(ClassExt::Alloc(self)));
if (new_ext == nullptr) {
// OOM allocating the classExt.
// TODO Should we restore the suppressed exception?
self->AssertPendingOOMException();
return nullptr;
} else {
MemberOffset ext_offset(OFFSET_OF_OBJECT_MEMBER(Class, ext_data_));
bool set;
// Set the ext_data_ field using CAS semantics.
if (Runtime::Current()->IsActiveTransaction()) {
set = h_this->CasFieldObject<true>(ext_offset,
nullptr,
new_ext.Get(),
CASMode::kStrong,
std::memory_order_seq_cst);
} else {
set = h_this->CasFieldObject<false>(ext_offset,
nullptr,
new_ext.Get(),
CASMode::kStrong,
std::memory_order_seq_cst);
}
ObjPtr<ClassExt> ret(set ? new_ext.Get() : h_this->GetExtData());
DCHECK(!set || h_this->GetExtData() == new_ext.Get());
CHECK(!ret.IsNull());
// Restore the exception if there was one.
if (throwable != nullptr) {
self->SetException(throwable.Get());
}
return ret;
}
}
template <typename T>
static void CheckSetStatus(Thread* self, T thiz, ClassStatus new_status, ClassStatus old_status)
REQUIRES_SHARED(Locks::mutator_lock_) {
if (UNLIKELY(new_status <= old_status && new_status != ClassStatus::kErrorUnresolved &&
new_status != ClassStatus::kErrorResolved && new_status != ClassStatus::kRetired)) {
LOG(FATAL) << "Unexpected change back of class status for " << thiz->PrettyClass() << " "
<< old_status << " -> " << new_status;
}
if (old_status == ClassStatus::kInitialized) {
// We do not hold the lock for making the class visibly initialized
// as this is unnecessary and could lead to deadlocks.
CHECK_EQ(new_status, ClassStatus::kVisiblyInitialized);
} else if ((new_status >= ClassStatus::kResolved || old_status >= ClassStatus::kResolved) &&
!Locks::mutator_lock_->IsExclusiveHeld(self)) {
// When classes are being resolved the resolution code should hold the
// lock or have everything else suspended
CHECK_EQ(thiz->GetLockOwnerThreadId(), self->GetThreadId())
<< "Attempt to change status of class while not holding its lock: " << thiz->PrettyClass()
<< " " << old_status << " -> " << new_status;
}
if (UNLIKELY(Locks::mutator_lock_->IsExclusiveHeld(self))) {
CHECK(!Class::IsErroneous(new_status))
<< "status " << new_status
<< " cannot be set while suspend-all is active. Would require allocations.";
CHECK(thiz->IsResolved())
<< thiz->PrettyClass()
<< " not resolved during suspend-all status change. Waiters might be missed!";
}
}
void Class::SetStatusInternal(ClassStatus new_status) {
if (kBitstringSubtypeCheckEnabled) {
// FIXME: This looks broken with respect to aborted transactions.
SubtypeCheck<ObjPtr<mirror::Class>>::WriteStatus(this, new_status);
} else {
// The ClassStatus is always in the 4 most-significant bits of status_.
static_assert(sizeof(status_) == sizeof(uint32_t), "Size of status_ not equal to uint32");
uint32_t new_status_value = static_cast<uint32_t>(new_status) << (32 - kClassStatusBitSize);
if (Runtime::Current()->IsActiveTransaction()) {
SetField32Volatile<true>(StatusOffset(), new_status_value);
} else {
SetField32Volatile<false>(StatusOffset(), new_status_value);
}
}
}
void Class::SetStatusLocked(ClassStatus new_status) {
ClassStatus old_status = GetStatus();
CheckSetStatus(Thread::Current(), this, new_status, old_status);
SetStatusInternal(new_status);
}
void Class::SetStatus(Handle<Class> h_this, ClassStatus new_status, Thread* self) {
ClassStatus old_status = h_this->GetStatus();
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
bool class_linker_initialized = class_linker != nullptr && class_linker->IsInitialized();
if (LIKELY(class_linker_initialized)) {
CheckSetStatus(self, h_this, new_status, old_status);
}
if (UNLIKELY(IsErroneous(new_status))) {
CHECK(!h_this->IsErroneous())
<< "Attempt to set as erroneous an already erroneous class "
<< h_this->PrettyClass()
<< " old_status: " << old_status << " new_status: " << new_status;
CHECK_EQ(new_status == ClassStatus::kErrorResolved, old_status >= ClassStatus::kResolved);
if (VLOG_IS_ON(class_linker)) {
LOG(ERROR) << "Setting " << h_this->PrettyDescriptor() << " to erroneous.";
if (self->IsExceptionPending()) {
LOG(ERROR) << "Exception: " << self->GetException()->Dump();
}
}
ObjPtr<ClassExt> ext(EnsureExtDataPresent(h_this, self));
if (!ext.IsNull()) {
self->AssertPendingException();
ext->SetVerifyError(self->GetException());
} else {
self->AssertPendingOOMException();
}
self->AssertPendingException();
}
h_this->SetStatusInternal(new_status);
// Setting the object size alloc fast path needs to be after the status write so that if the
// alloc path sees a valid object size, we would know that it's initialized as long as it has a
// load-acquire/fake dependency.
if (new_status == ClassStatus::kVisiblyInitialized && !h_this->IsVariableSize()) {
DCHECK_EQ(h_this->GetObjectSizeAllocFastPath(), std::numeric_limits<uint32_t>::max());
// Finalizable objects must always go slow path.
if (!h_this->IsFinalizable()) {
h_this->SetObjectSizeAllocFastPath(RoundUp(h_this->GetObjectSize(), kObjectAlignment));
}
}
if (kIsDebugBuild && new_status >= ClassStatus::kInitialized) {
CHECK(h_this->WasVerificationAttempted()) << h_this->PrettyClassAndClassLoader();
}
if (!class_linker_initialized) {
// When the class linker is being initialized its single threaded and by definition there can be
// no waiters. During initialization classes may appear temporary but won't be retired as their
// size was statically computed.
} else {
// Classes that are being resolved or initialized need to notify waiters that the class status
// changed. See ClassLinker::EnsureResolved and ClassLinker::WaitForInitializeClass.
if (h_this->IsTemp()) {
// Class is a temporary one, ensure that waiters for resolution get notified of retirement
// so that they can grab the new version of the class from the class linker's table.
CHECK_LT(new_status, ClassStatus::kResolved) << h_this->PrettyDescriptor();
if (new_status == ClassStatus::kRetired || new_status == ClassStatus::kErrorUnresolved) {
h_this->NotifyAll(self);
}
} else if (old_status == ClassStatus::kInitialized) {
// Do not notify for transition from kInitialized to ClassStatus::kVisiblyInitialized.
// This is a hidden transition, not observable by bytecode.
DCHECK_EQ(new_status, ClassStatus::kVisiblyInitialized); // Already CHECK()ed above.
} else {
CHECK_NE(new_status, ClassStatus::kRetired);
if (old_status >= ClassStatus::kResolved || new_status >= ClassStatus::kResolved) {
h_this->NotifyAll(self);
}
}
}
}
void Class::SetStatusForPrimitiveOrArray(ClassStatus new_status) {
DCHECK(IsPrimitive<kVerifyNone>() || IsArrayClass<kVerifyNone>());
DCHECK(!IsErroneous(new_status));
DCHECK(!IsErroneous(GetStatus<kVerifyNone>()));
DCHECK_GT(new_status, GetStatus<kVerifyNone>());
if (kBitstringSubtypeCheckEnabled) {
LOG(FATAL) << "Unimplemented";
}
// The ClassStatus is always in the 4 most-significant bits of status_.
static_assert(sizeof(status_) == sizeof(uint32_t), "Size of status_ not equal to uint32");
uint32_t new_status_value = static_cast<uint32_t>(new_status) << (32 - kClassStatusBitSize);
// Use normal store. For primitives and core arrays classes (Object[],
// Class[], String[] and primitive arrays), the status is set while the
// process is still single threaded. For other arrays classes, it is set
// in a pre-fence visitor which initializes all fields and the subsequent
// fence together with address dependency shall ensure memory visibility.
SetField32</*kTransactionActive=*/ false,
/*kCheckTransaction=*/ false,
kVerifyNone>(StatusOffset(), new_status_value);
// Do not update `object_alloc_fast_path_`. Arrays are variable size and
// instances of primitive classes cannot be created at all.
if (kIsDebugBuild && new_status >= ClassStatus::kInitialized) {
CHECK(WasVerificationAttempted()) << PrettyClassAndClassLoader();
}
// There can be no waiters to notify as these classes are initialized
// before another thread can see them.
}
void Class::SetDexCache(ObjPtr<DexCache> new_dex_cache) {
SetFieldObjectTransaction(OFFSET_OF_OBJECT_MEMBER(Class, dex_cache_), new_dex_cache);
}
void Class::SetClassSize(uint32_t new_class_size) {
if (kIsDebugBuild && new_class_size < GetClassSize()) {
DumpClass(LOG_STREAM(FATAL_WITHOUT_ABORT), kDumpClassFullDetail);
LOG(FATAL_WITHOUT_ABORT) << new_class_size << " vs " << GetClassSize();
LOG(FATAL) << "class=" << PrettyTypeOf();
}
SetField32</*kTransactionActive=*/ false, /*kCheckTransaction=*/ false>(
OFFSET_OF_OBJECT_MEMBER(Class, class_size_), new_class_size);
}
ObjPtr<Class> Class::GetObsoleteClass() {
ObjPtr<ClassExt> ext(GetExtData());
if (ext.IsNull()) {
return nullptr;
} else {
return ext->GetObsoleteClass();
}
}
// Return the class' name. The exact format is bizarre, but it's the specified behavior for
// Class.getName: keywords for primitive types, regular "[I" form for primitive arrays (so "int"
// but "[I"), and arrays of reference types written between "L" and ";" but with dots rather than
// slashes (so "java.lang.String" but "[Ljava.lang.String;"). Madness.
ObjPtr<String> Class::ComputeName(Handle<Class> h_this) {
ObjPtr<String> name = h_this->GetName();
if (name != nullptr) {
return name;
}
std::string temp;
const char* descriptor = h_this->GetDescriptor(&temp);
Thread* self = Thread::Current();
if ((descriptor[0] != 'L') && (descriptor[0] != '[')) {
// The descriptor indicates that this is the class for
// a primitive type; special-case the return value.
const char* c_name = nullptr;
switch (descriptor[0]) {
case 'Z': c_name = "boolean"; break;
case 'B': c_name = "byte"; break;
case 'C': c_name = "char"; break;
case 'S': c_name = "short"; break;
case 'I': c_name = "int"; break;
case 'J': c_name = "long"; break;
case 'F': c_name = "float"; break;
case 'D': c_name = "double"; break;
case 'V': c_name = "void"; break;
default:
LOG(FATAL) << "Unknown primitive type: " << PrintableChar(descriptor[0]);
}
name = String::AllocFromModifiedUtf8(self, c_name);
} else {
// Convert the UTF-8 name to a java.lang.String. The name must use '.' to separate package
// components.
name = String::AllocFromModifiedUtf8(self, DescriptorToDot(descriptor).c_str());
}
h_this->SetName(name);
return name;
}
void Class::DumpClass(std::ostream& os, int flags) {
if ((flags & kDumpClassFullDetail) == 0) {
os << PrettyClass();
if ((flags & kDumpClassClassLoader) != 0) {
os << ' ' << GetClassLoader();
}
if ((flags & kDumpClassInitialized) != 0) {
os << ' ' << GetStatus();
}
os << "\n";
return;
}
Thread* const self = Thread::Current();
StackHandleScope<2> hs(self);
Handle<Class> h_this(hs.NewHandle(this));
Handle<Class> h_super(hs.NewHandle(GetSuperClass()));
auto image_pointer_size = Runtime::Current()->GetClassLinker()->GetImagePointerSize();
std::string temp;
os << "----- " << (IsInterface() ? "interface" : "class") << " "
<< "'" << GetDescriptor(&temp) << "' cl=" << GetClassLoader() << " -----\n",
os << " objectSize=" << SizeOf() << " "
<< "(" << (h_super != nullptr ? h_super->SizeOf() : -1) << " from super)\n",
os << StringPrintf(" access=0x%04x.%04x\n",
GetAccessFlags() >> 16, GetAccessFlags() & kAccJavaFlagsMask);
if (h_super != nullptr) {
os << " super='" << h_super->PrettyClass() << "' (cl=" << h_super->GetClassLoader()
<< ")\n";
}
if (IsArrayClass()) {
os << " componentType=" << PrettyClass(GetComponentType()) << "\n";
}
const size_t num_direct_interfaces = NumDirectInterfaces();
if (num_direct_interfaces > 0) {
os << " interfaces (" << num_direct_interfaces << "):\n";
for (size_t i = 0; i < num_direct_interfaces; ++i) {
ObjPtr<Class> interface = GetDirectInterface(self, h_this.Get(), i);
if (interface == nullptr) {
os << StringPrintf(" %2zd: nullptr!\n", i);
} else {
ObjPtr<ClassLoader> cl = interface->GetClassLoader();
os << StringPrintf(" %2zd: %s (cl=%p)\n", i, PrettyClass(interface).c_str(), cl.Ptr());
}
}
}
if (!IsLoaded()) {
os << " class not yet loaded";
} else {
// After this point, this may have moved due to GetDirectInterface.
os << " vtable (" << h_this->NumVirtualMethods() << " entries, "
<< (h_super != nullptr ? h_super->NumVirtualMethods() : 0) << " in super):\n";
for (size_t i = 0; i < NumVirtualMethods(); ++i) {
os << StringPrintf(" %2zd: %s\n", i, ArtMethod::PrettyMethod(
h_this->GetVirtualMethodDuringLinking(i, image_pointer_size)).c_str());
}
os << " direct methods (" << h_this->NumDirectMethods() << " entries):\n";
for (size_t i = 0; i < h_this->NumDirectMethods(); ++i) {
os << StringPrintf(" %2zd: %s\n", i, ArtMethod::PrettyMethod(
h_this->GetDirectMethod(i, image_pointer_size)).c_str());
}
if (h_this->NumStaticFields() > 0) {
os << " static fields (" << h_this->NumStaticFields() << " entries):\n";
if (h_this->IsResolved()) {
for (size_t i = 0; i < h_this->NumStaticFields(); ++i) {
os << StringPrintf(" %2zd: %s\n", i,
ArtField::PrettyField(h_this->GetStaticField(i)).c_str());
}
} else {
os << " <not yet available>";
}
}
if (h_this->NumInstanceFields() > 0) {
os << " instance fields (" << h_this->NumInstanceFields() << " entries):\n";
if (h_this->IsResolved()) {
for (size_t i = 0; i < h_this->NumInstanceFields(); ++i) {
os << StringPrintf(" %2zd: %s\n", i,
ArtField::PrettyField(h_this->GetInstanceField(i)).c_str());
}
} else {
os << " <not yet available>";
}
}
}
}
void Class::SetReferenceInstanceOffsets(uint32_t new_reference_offsets) {
if (kIsDebugBuild && new_reference_offsets != kClassWalkSuper) {
// Check that the number of bits set in the reference offset bitmap
// agrees with the number of references.
uint32_t count = 0;
for (ObjPtr<Class> c = this; c != nullptr; c = c->GetSuperClass()) {
count += c->NumReferenceInstanceFieldsDuringLinking();
}
// +1 for the Class in Object.
CHECK_EQ(static_cast<uint32_t>(POPCOUNT(new_reference_offsets)) + 1, count);
}
// Not called within a transaction.
SetField32<false>(OFFSET_OF_OBJECT_MEMBER(Class, reference_instance_offsets_),
new_reference_offsets);
}
bool Class::IsInSamePackage(std::string_view descriptor1, std::string_view descriptor2) {
size_t i = 0;
size_t min_length = std::min(descriptor1.size(), descriptor2.size());
while (i < min_length && descriptor1[i] == descriptor2[i]) {
++i;
}
if (descriptor1.find('/', i) != std::string_view::npos ||
descriptor2.find('/', i) != std::string_view::npos) {
return false;
} else {
return true;
}
}
bool Class::IsInSamePackage(ObjPtr<Class> that) {
ObjPtr<Class> klass1 = this;
ObjPtr<Class> klass2 = that;
if (klass1 == klass2) {
return true;
}
// Class loaders must match.
if (klass1->GetClassLoader() != klass2->GetClassLoader()) {
return false;
}
// Arrays are in the same package when their element classes are.
while (klass1->IsArrayClass()) {
klass1 = klass1->GetComponentType();
}
while (klass2->IsArrayClass()) {
klass2 = klass2->GetComponentType();
}
// trivial check again for array types
if (klass1 == klass2) {
return true;
}
// Compare the package part of the descriptor string.
std::string temp1, temp2;
return IsInSamePackage(klass1->GetDescriptor(&temp1), klass2->GetDescriptor(&temp2));
}
bool Class::IsThrowableClass() {
return GetClassRoot<mirror::Throwable>()->IsAssignableFrom(this);
}
template <typename SignatureType>
static inline ArtMethod* FindInterfaceMethodWithSignature(ObjPtr<Class> klass,
std::string_view name,
const SignatureType& signature,
PointerSize pointer_size)
REQUIRES_SHARED(Locks::mutator_lock_) {
// If the current class is not an interface, skip the search of its declared methods;
// such lookup is used only to distinguish between IncompatibleClassChangeError and
// NoSuchMethodError and the caller has already tried to search methods in the class.
if (LIKELY(klass->IsInterface())) {
// Search declared methods, both direct and virtual.
// (This lookup is used also for invoke-static on interface classes.)
for (ArtMethod& method : klass->GetDeclaredMethodsSlice(pointer_size)) {
if (method.GetNameView() == name && method.GetSignature() == signature) {
return &method;
}
}
}
// TODO: If there is a unique maximally-specific non-abstract superinterface method,
// we should return it, otherwise an arbitrary one can be returned.
ObjPtr<IfTable> iftable = klass->GetIfTable();
for (int32_t i = 0, iftable_count = iftable->Count(); i < iftable_count; ++i) {
ObjPtr<Class> iface = iftable->GetInterface(i);
for (ArtMethod& method : iface->GetVirtualMethodsSlice(pointer_size)) {
if (method.GetNameView() == name && method.GetSignature() == signature) {
return &method;
}
}
}
// Then search for public non-static methods in the java.lang.Object.
if (LIKELY(klass->IsInterface())) {
ObjPtr<Class> object_class = klass->GetSuperClass();
DCHECK(object_class->IsObjectClass());
for (ArtMethod& method : object_class->GetDeclaredMethodsSlice(pointer_size)) {
if (method.IsPublic() && !method.IsStatic() &&
method.GetNameView() == name && method.GetSignature() == signature) {
return &method;
}
}
}
return nullptr;
}
ArtMethod* Class::FindInterfaceMethod(std::string_view name,
std::string_view signature,
PointerSize pointer_size) {
return FindInterfaceMethodWithSignature(this, name, signature, pointer_size);
}
ArtMethod* Class::FindInterfaceMethod(std::string_view name,
const Signature& signature,
PointerSize pointer_size) {
return FindInterfaceMethodWithSignature(this, name, signature, pointer_size);
}
ArtMethod* Class::FindInterfaceMethod(ObjPtr<DexCache> dex_cache,
uint32_t dex_method_idx,
PointerSize pointer_size) {
// We always search by name and signature, ignoring the type index in the MethodId.
const DexFile& dex_file = *dex_cache->GetDexFile();
const dex::MethodId& method_id = dex_file.GetMethodId(dex_method_idx);
std::string_view name = dex_file.StringViewByIdx(method_id.name_idx_);
const Signature signature = dex_file.GetMethodSignature(method_id);
return FindInterfaceMethod(name, signature, pointer_size);
}
static inline bool IsValidInheritanceCheck(ObjPtr<mirror::Class> klass,
ObjPtr<mirror::Class> declaring_class)
REQUIRES_SHARED(Locks::mutator_lock_) {
if (klass->IsArrayClass()) {
return declaring_class->IsObjectClass();
} else if (klass->IsInterface()) {
return declaring_class->IsObjectClass() || declaring_class == klass;
} else {
return klass->IsSubClass(declaring_class);
}
}
static inline bool IsInheritedMethod(ObjPtr<mirror::Class> klass,
ObjPtr<mirror::Class> declaring_class,
ArtMethod& method)
REQUIRES_SHARED(Locks::mutator_lock_) {
DCHECK_EQ(declaring_class, method.GetDeclaringClass());
DCHECK_NE(klass, declaring_class);
DCHECK(IsValidInheritanceCheck(klass, declaring_class));
uint32_t access_flags = method.GetAccessFlags();
if ((access_flags & (kAccPublic | kAccProtected)) != 0) {
return true;
}
if ((access_flags & kAccPrivate) != 0) {
return false;
}
for (; klass != declaring_class; klass = klass->GetSuperClass()) {
if (!klass->IsInSamePackage(declaring_class)) {
return false;
}
}
return true;
}
template <typename SignatureType>
static inline ArtMethod* FindClassMethodWithSignature(ObjPtr<Class> this_klass,
std::string_view name,
const SignatureType& signature,
PointerSize pointer_size)
REQUIRES_SHARED(Locks::mutator_lock_) {
// Search declared methods first.
for (ArtMethod& method : this_klass->GetDeclaredMethodsSlice(pointer_size)) {
ArtMethod* np_method = method.GetInterfaceMethodIfProxy(pointer_size);
if (np_method->GetName() == name && np_method->GetSignature() == signature) {
return &method;
}
}
// Then search the superclass chain. If we find an inherited method, return it.
// If we find a method that's not inherited because of access restrictions,
// try to find a method inherited from an interface in copied methods.
ObjPtr<Class> klass = this_klass->GetSuperClass();
ArtMethod* uninherited_method = nullptr;
for (; klass != nullptr; klass = klass->GetSuperClass()) {
DCHECK(!klass->IsProxyClass());
for (ArtMethod& method : klass->GetDeclaredMethodsSlice(pointer_size)) {
if (method.GetName() == name && method.GetSignature() == signature) {
if (IsInheritedMethod(this_klass, klass, method)) {
return &method;
}
uninherited_method = &method;
break;
}
}
if (uninherited_method != nullptr) {
break;
}
}
// Then search copied methods.
// If we found a method that's not inherited, stop the search in its declaring class.
ObjPtr<Class> end_klass = klass;
DCHECK_EQ(uninherited_method != nullptr, end_klass != nullptr);
klass = this_klass;
if (UNLIKELY(klass->IsProxyClass())) {
DCHECK(klass->GetCopiedMethodsSlice(pointer_size).empty());
klass = klass->GetSuperClass();
}
for (; klass != end_klass; klass = klass->GetSuperClass()) {
DCHECK(!klass->IsProxyClass());
for (ArtMethod& method : klass->GetCopiedMethodsSlice(pointer_size)) {
if (method.GetName() == name && method.GetSignature() == signature) {
return &method; // No further check needed, copied methods are inherited by definition.
}
}
}
return uninherited_method; // Return the `uninherited_method` if any.
}
ArtMethod* Class::FindClassMethod(std::string_view name,
std::string_view signature,
PointerSize pointer_size) {
return FindClassMethodWithSignature(this, name, signature, pointer_size);
}
ArtMethod* Class::FindClassMethod(std::string_view name,
const Signature& signature,
PointerSize pointer_size) {
return FindClassMethodWithSignature(this, name, signature, pointer_size);
}
ArtMethod* Class::FindClassMethod(ObjPtr<DexCache> dex_cache,
uint32_t dex_method_idx,
PointerSize pointer_size) {
// FIXME: Hijacking a proxy class by a custom class loader can break this assumption.
DCHECK(!IsProxyClass());
// First try to find a declared method by dex_method_idx if we have a dex_cache match.
ObjPtr<DexCache> this_dex_cache = GetDexCache();
if (this_dex_cache == dex_cache) {
// Lookup is always performed in the class referenced by the MethodId.
DCHECK_EQ(dex_type_idx_, GetDexFile().GetMethodId(dex_method_idx).class_idx_.index_);
for (ArtMethod& method : GetDeclaredMethodsSlice(pointer_size)) {
if (method.GetDexMethodIndex() == dex_method_idx) {
return &method;
}
}
}
// If not found, we need to search by name and signature.
const DexFile& dex_file = *dex_cache->GetDexFile();
const dex::MethodId& method_id = dex_file.GetMethodId(dex_method_idx);
const Signature signature = dex_file.GetMethodSignature(method_id);
std::string_view name; // Delay strlen() until actually needed.
// If we do not have a dex_cache match, try to find the declared method in this class now.
if (this_dex_cache != dex_cache && !GetDeclaredMethodsSlice(pointer_size).empty()) {
DCHECK(name.empty());
// Avoid string comparisons by comparing the respective unicode lengths first.
uint32_t length, other_length; // UTF16 length.
name = dex_file.GetMethodName(method_id, &length);
for (ArtMethod& method : GetDeclaredMethodsSlice(pointer_size)) {
DCHECK_NE(method.GetDexMethodIndex(), dex::kDexNoIndex);
const char* other_name = method.GetDexFile()->GetMethodName(
method.GetDexMethodIndex(), &other_length);
if (length == other_length && name == other_name && signature == method.GetSignature()) {
return &method;
}
}
}
// Then search the superclass chain. If we find an inherited method, return it.
// If we find a method that's not inherited because of access restrictions,
// try to find a method inherited from an interface in copied methods.
ArtMethod* uninherited_method = nullptr;
ObjPtr<Class> klass = GetSuperClass();
for (; klass != nullptr; klass = klass->GetSuperClass()) {
ArtMethod* candidate_method = nullptr;
ArraySlice<ArtMethod> declared_methods = klass->GetDeclaredMethodsSlice(pointer_size);
if (klass->GetDexCache() == dex_cache) {
// Matching dex_cache. We cannot compare the `dex_method_idx` anymore because
// the type index differs, so compare the name index and proto index.
for (ArtMethod& method : declared_methods) {
const dex::MethodId& cmp_method_id = dex_file.GetMethodId(method.GetDexMethodIndex());
if (cmp_method_id.name_idx_ == method_id.name_idx_ &&
cmp_method_id.proto_idx_ == method_id.proto_idx_) {
candidate_method = &method;
break;
}
}
} else {
if (!declared_methods.empty() && name.empty()) {
name = dex_file.StringDataByIdx(method_id.name_idx_);
}
for (ArtMethod& method : declared_methods) {
if (method.GetName() == name && method.GetSignature() == signature) {
candidate_method = &method;
break;
}
}
}
if (candidate_method != nullptr) {
if (IsInheritedMethod(this, klass, *candidate_method)) {
return candidate_method;
} else {
uninherited_method = candidate_method;
break;
}
}
}
// Then search copied methods.
// If we found a method that's not inherited, stop the search in its declaring class.
ObjPtr<Class> end_klass = klass;
DCHECK_EQ(uninherited_method != nullptr, end_klass != nullptr);
// After we have searched the declared methods of the super-class chain,
// search copied methods which can contain methods from interfaces.
for (klass = this; klass != end_klass; klass = klass->GetSuperClass()) {
ArraySlice<ArtMethod> copied_methods = klass->GetCopiedMethodsSlice(pointer_size);
if (!copied_methods.empty() && name.empty()) {
name = dex_file.StringDataByIdx(method_id.name_idx_);
}
for (ArtMethod& method : copied_methods) {
if (method.GetName() == name && method.GetSignature() == signature) {
return &method; // No further check needed, copied methods are inherited by definition.
}
}
}
return uninherited_method; // Return the `uninherited_method` if any.
}
ArtMethod* Class::FindConstructor(std::string_view signature, PointerSize pointer_size) {
// Internal helper, never called on proxy classes. We can skip GetInterfaceMethodIfProxy().
DCHECK(!IsProxyClass());
std::string_view name("<init>");
for (ArtMethod& method : GetDirectMethodsSliceUnchecked(pointer_size)) {
if (method.GetName() == name && method.GetSignature() == signature) {
return &method;
}
}
return nullptr;
}
ArtMethod* Class::FindDeclaredDirectMethodByName(std::string_view name, PointerSize pointer_size) {
for (auto& method : GetDirectMethods(pointer_size)) {
ArtMethod* const np_method = method.GetInterfaceMethodIfProxy(pointer_size);
if (name == np_method->GetName()) {
return &method;
}
}
return nullptr;
}
ArtMethod* Class::FindDeclaredVirtualMethodByName(std::string_view name, PointerSize pointer_size) {
for (auto& method : GetVirtualMethods(pointer_size)) {
ArtMethod* const np_method = method.GetInterfaceMethodIfProxy(pointer_size);
if (name == np_method->GetName()) {
return &method;
}
}
return nullptr;
}
ArtMethod* Class::FindVirtualMethodForInterfaceSuper(ArtMethod* method, PointerSize pointer_size) {
DCHECK(method->GetDeclaringClass()->IsInterface());
DCHECK(IsInterface()) << "Should only be called on a interface class";
// Check if we have one defined on this interface first. This includes searching copied ones to
// get any conflict methods. Conflict methods are copied into each subtype from the supertype. We
// don't do any indirect method checks here.
for (ArtMethod& iface_method : GetVirtualMethods(pointer_size)) {
if (method->HasSameNameAndSignature(&iface_method)) {
return &iface_method;
}
}
std::vector<ArtMethod*> abstract_methods;
// Search through the IFTable for a working version. We don't need to check for conflicts
// because if there was one it would appear in this classes virtual_methods_ above.
Thread* self = Thread::Current();
StackHandleScope<2> hs(self);
MutableHandle<IfTable> iftable(hs.NewHandle(GetIfTable()));
MutableHandle<Class> iface(hs.NewHandle<Class>(nullptr));
size_t iftable_count = GetIfTableCount();
// Find the method. We don't need to check for conflicts because they would have been in the
// copied virtuals of this interface. Order matters, traverse in reverse topological order; most
// subtypiest interfaces get visited first.
for (size_t k = iftable_count; k != 0;) {
k--;
DCHECK_LT(k, iftable->Count());
iface.Assign(iftable->GetInterface(k));
// Iterate through every declared method on this interface. Each direct method's name/signature
// is unique so the order of the inner loop doesn't matter.
for (auto& method_iter : iface->GetDeclaredVirtualMethods(pointer_size)) {
ArtMethod* current_method = &method_iter;
if (current_method->HasSameNameAndSignature(method)) {
if (current_method->IsDefault()) {
// Handle JLS soft errors, a default method from another superinterface tree can
// "override" an abstract method(s) from another superinterface tree(s). To do this,
// ignore any [default] method which are dominated by the abstract methods we've seen so
// far. Check if overridden by any in abstract_methods. We do not need to check for
// default_conflicts because we would hit those before we get to this loop.
bool overridden = false;
for (ArtMethod* possible_override : abstract_methods) {
DCHECK(possible_override->HasSameNameAndSignature(current_method));
if (iface->IsAssignableFrom(possible_override->GetDeclaringClass())) {
overridden = true;
break;
}
}
if (!overridden) {
return current_method;
}
} else {
// Is not default.
// This might override another default method. Just stash it for now.
abstract_methods.push_back(current_method);
}
}
}
}
// If we reach here we either never found any declaration of the method (in which case
// 'abstract_methods' is empty or we found no non-overriden default methods in which case
// 'abstract_methods' contains a number of abstract implementations of the methods. We choose one
// of these arbitrarily.
return abstract_methods.empty() ? nullptr : abstract_methods[0];
}
ArtMethod* Class::FindClassInitializer(PointerSize pointer_size) {
for (ArtMethod& method : GetDirectMethods(pointer_size)) {
if (method.IsClassInitializer()) {
DCHECK_STREQ(method.GetName(), "<clinit>");
DCHECK_STREQ(method.GetSignature().ToString().c_str(), "()V");
return &method;
}
}
return nullptr;
}
// Custom binary search to avoid double comparisons from std::binary_search.
static ArtField* FindFieldByNameAndType(LengthPrefixedArray<ArtField>* fields,
std::string_view name,
std::string_view type)
REQUIRES_SHARED(Locks::mutator_lock_) {
if (fields == nullptr) {
return nullptr;
}
size_t low = 0;
size_t high = fields->size();
ArtField* ret = nullptr;
while (low < high) {
size_t mid = (low + high) / 2;
ArtField& field = fields->At(mid);
// Fields are sorted by class, then name, then type descriptor. This is verified in dex file
// verifier. There can be multiple fields with the same in the same class name due to proguard.
// Note: std::string_view::compare() uses lexicographical comparison and treats the `char` as
// unsigned; for modified-UTF-8 without embedded nulls this is consistent with the
// CompareModifiedUtf8ToModifiedUtf8AsUtf16CodePointValues() ordering.
int result = std::string_view(field.GetName()).compare(name);
if (result == 0) {
result = std::string_view(field.GetTypeDescriptor()).compare(type);
}
if (result < 0) {
low = mid + 1;
} else if (result > 0) {
high = mid;
} else {
ret = &field;
break;
}
}
if (kIsDebugBuild) {
ArtField* found = nullptr;
for (ArtField& field : MakeIterationRangeFromLengthPrefixedArray(fields)) {
if (name == field.GetName() && type == field.GetTypeDescriptor()) {
found = &field;
break;
}
}
CHECK_EQ(found, ret) << "Found " << found->PrettyField() << " vs " << ret->PrettyField();
}
return ret;
}
ArtField* Class::FindDeclaredInstanceField(std::string_view name, std::string_view type) {
// Binary search by name. Interfaces are not relevant because they can't contain instance fields.
return FindFieldByNameAndType(GetIFieldsPtr(), name, type);
}
ArtField* Class::FindDeclaredInstanceField(ObjPtr<DexCache> dex_cache, uint32_t dex_field_idx) {
if (GetDexCache() == dex_cache) {
for (ArtField& field : GetIFields()) {
if (field.GetDexFieldIndex() == dex_field_idx) {
return &field;
}
}
}
return nullptr;
}
ArtField* Class::FindInstanceField(std::string_view name, std::string_view type) {
// Is the field in this class, or any of its superclasses?
// Interfaces are not relevant because they can't contain instance fields.
for (ObjPtr<Class> c = this; c != nullptr; c = c->GetSuperClass()) {
ArtField* f = c->FindDeclaredInstanceField(name, type);
if (f != nullptr) {
return f;
}
}
return nullptr;
}
ArtField* Class::FindInstanceField(ObjPtr<DexCache> dex_cache, uint32_t dex_field_idx) {
// Is the field in this class, or any of its superclasses?
// Interfaces are not relevant because they can't contain instance fields.
for (ObjPtr<Class> c = this; c != nullptr; c = c->GetSuperClass()) {
ArtField* f = c->FindDeclaredInstanceField(dex_cache, dex_field_idx);
if (f != nullptr) {
return f;
}
}
return nullptr;
}
ArtField* Class::FindDeclaredStaticField(std::string_view name, std::string_view type) {
DCHECK(!type.empty());
return FindFieldByNameAndType(GetSFieldsPtr(), name, type);
}
ArtField* Class::FindDeclaredStaticField(ObjPtr<DexCache> dex_cache, uint32_t dex_field_idx) {
if (dex_cache == GetDexCache()) {
for (ArtField& field : GetSFields()) {
if (field.GetDexFieldIndex() == dex_field_idx) {
return &field;
}
}
}
return nullptr;
}
ArtField* Class::FindStaticField(Thread* self,
ObjPtr<Class> klass,
std::string_view name,
std::string_view type) {
// Is the field in this class (or its interfaces), or any of its
// superclasses (or their interfaces)?
for (ObjPtr<Class> k = klass; k != nullptr; k = k->GetSuperClass()) {
// Is the field in this class?
ArtField* f = k->FindDeclaredStaticField(name, type);
if (f != nullptr) {
return f;
}
// Is this field in any of this class' interfaces?
for (uint32_t i = 0, num_interfaces = k->NumDirectInterfaces(); i != num_interfaces; ++i) {
ObjPtr<Class> interface = GetDirectInterface(self, k, i);
DCHECK(interface != nullptr);
f = FindStaticField(self, interface, name, type);
if (f != nullptr) {
return f;
}
}
}
return nullptr;
}
ArtField* Class::FindStaticField(Thread* self,
ObjPtr<Class> klass,
ObjPtr<DexCache> dex_cache,
uint32_t dex_field_idx) {
for (ObjPtr<Class> k = klass; k != nullptr; k = k->GetSuperClass()) {
// Is the field in this class?
ArtField* f = k->FindDeclaredStaticField(dex_cache, dex_field_idx);
if (f != nullptr) {
return f;
}
// Though GetDirectInterface() should not cause thread suspension when called
// from here, it takes a Handle as an argument, so we need to wrap `k`.
ScopedAssertNoThreadSuspension ants(__FUNCTION__);
// Is this field in any of this class' interfaces?
for (uint32_t i = 0, num_interfaces = k->NumDirectInterfaces(); i != num_interfaces; ++i) {
ObjPtr<Class> interface = GetDirectInterface(self, k, i);
DCHECK(interface != nullptr);
f = FindStaticField(self, interface, dex_cache, dex_field_idx);
if (f != nullptr) {
return f;
}
}
}
return nullptr;
}
ArtField* Class::FindField(Thread* self,
ObjPtr<Class> klass,
std::string_view name,
std::string_view type) {
// Find a field using the JLS field resolution order
for (ObjPtr<Class> k = klass; k != nullptr; k = k->GetSuperClass()) {
// Is the field in this class?
ArtField* f = k->FindDeclaredInstanceField(name, type);
if (f != nullptr) {
return f;
}
f = k->FindDeclaredStaticField(name, type);
if (f != nullptr) {
return f;
}
// Is this field in any of this class' interfaces?
for (uint32_t i = 0, num_interfaces = k->NumDirectInterfaces(); i != num_interfaces; ++i) {
ObjPtr<Class> interface = GetDirectInterface(self, k, i);
DCHECK(interface != nullptr);
f = FindStaticField(self, interface, name, type);
if (f != nullptr) {
return f;
}
}
}
return nullptr;
}
void Class::ClearSkipAccessChecksFlagOnAllMethods(PointerSize pointer_size) {
DCHECK(IsVerified());
for (auto& m : GetMethods(pointer_size)) {
if (!m.IsNative() && m.IsInvokable()) {
m.ClearSkipAccessChecks();
}
}
}
void Class::ClearMustCountLocksFlagOnAllMethods(PointerSize pointer_size) {
DCHECK(IsVerified());
for (auto& m : GetMethods(pointer_size)) {
if (!m.IsNative() && m.IsInvokable()) {
m.ClearMustCountLocks();
}
}
}
void Class::ClearDontCompileFlagOnAllMethods(PointerSize pointer_size) {
DCHECK(IsVerified());
for (auto& m : GetMethods(pointer_size)) {
if (!m.IsNative() && m.IsInvokable()) {
m.ClearDontCompile();
}
}
}
void Class::SetSkipAccessChecksFlagOnAllMethods(PointerSize pointer_size) {
DCHECK(IsVerified());
for (auto& m : GetMethods(pointer_size)) {
if (!m.IsNative() && m.IsInvokable()) {
m.SetSkipAccessChecks();
}
}
}
const char* Class::GetDescriptor(std::string* storage) {
size_t dim = 0u;
ObjPtr<mirror::Class> klass = this;
while (klass->IsArrayClass()) {
++dim;
// No read barrier needed, we're reading a chain of constant references for comparison
// with null. Then we follow up below with reading constant references to read constant
// primitive data in both proxy and non-proxy paths. See ReadBarrierOption.
klass = klass->GetComponentType<kDefaultVerifyFlags, kWithoutReadBarrier>();
}
if (klass->IsProxyClass()) {
// No read barrier needed, the `name` field is constant for proxy classes and
// the contents of the String are also constant. See ReadBarrierOption.
ObjPtr<mirror::String> name = klass->GetName<kVerifyNone, kWithoutReadBarrier>();
DCHECK(name != nullptr);
*storage = DotToDescriptor(name->ToModifiedUtf8().c_str());
} else {
const char* descriptor;
if (klass->IsPrimitive()) {
descriptor = Primitive::Descriptor(klass->GetPrimitiveType());
} else {
const DexFile& dex_file = klass->GetDexFile();
const dex::TypeId& type_id = dex_file.GetTypeId(klass->GetDexTypeIndex());
descriptor = dex_file.GetTypeDescriptor(type_id);
}
if (dim == 0) {
return descriptor;
}
*storage = descriptor;
}
storage->insert(0u, dim, '[');
return storage->c_str();
}
const dex::ClassDef* Class::GetClassDef() {
uint16_t class_def_idx = GetDexClassDefIndex();
if (class_def_idx == DexFile::kDexNoIndex16) {
return nullptr;
}
return &GetDexFile().GetClassDef(class_def_idx);
}
dex::TypeIndex Class::GetDirectInterfaceTypeIdx(uint32_t idx) {
DCHECK(!IsPrimitive());
DCHECK(!IsArrayClass());
return GetInterfaceTypeList()->GetTypeItem(idx).type_idx_;
}
ObjPtr<Class> Class::GetDirectInterface(Thread* self, ObjPtr<Class> klass, uint32_t idx) {
DCHECK(klass != nullptr);
DCHECK(!klass->IsPrimitive());
if (klass->IsArrayClass()) {
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
// Use ClassLinker::LookupClass(); avoid poisoning ObjPtr<>s by ClassLinker::FindSystemClass().
ObjPtr<Class> interface;
if (idx == 0) {
interface = class_linker->LookupClass(self, "Ljava/lang/Cloneable;", nullptr);
} else {
DCHECK_EQ(1U, idx);
interface = class_linker->LookupClass(self, "Ljava/io/Serializable;", nullptr);
}
DCHECK(interface != nullptr);
return interface;
} else if (klass->IsProxyClass()) {
ObjPtr<ObjectArray<Class>> interfaces = klass->GetProxyInterfaces();
DCHECK(interfaces != nullptr);
return interfaces->Get(idx);
} else {
dex::TypeIndex type_idx = klass->GetDirectInterfaceTypeIdx(idx);
ObjPtr<Class> interface = Runtime::Current()->GetClassLinker()->LookupResolvedType(
type_idx, klass->GetDexCache(), klass->GetClassLoader());
return interface;
}
}
ObjPtr<Class> Class::ResolveDirectInterface(Thread* self, Handle<Class> klass, uint32_t idx) {
ObjPtr<Class> interface = GetDirectInterface(self, klass.Get(), idx);
if (interface == nullptr) {
DCHECK(!klass->IsArrayClass());
DCHECK(!klass->IsProxyClass());
dex::TypeIndex type_idx = klass->GetDirectInterfaceTypeIdx(idx);
interface = Runtime::Current()->GetClassLinker()->ResolveType(type_idx, klass.Get());
CHECK(interface != nullptr || self->IsExceptionPending());
}
return interface;
}
ObjPtr<Class> Class::GetCommonSuperClass(Handle<Class> klass) {
DCHECK(klass != nullptr);
DCHECK(!klass->IsInterface());
DCHECK(!IsInterface());
ObjPtr<Class> common_super_class = this;
while (!common_super_class->IsAssignableFrom(klass.Get())) {
ObjPtr<Class> old_common = common_super_class;
common_super_class = old_common->GetSuperClass();
DCHECK(common_super_class != nullptr) << old_common->PrettyClass();
}
return common_super_class;
}
const char* Class::GetSourceFile() {
const DexFile& dex_file = GetDexFile();
const dex::ClassDef* dex_class_def = GetClassDef();
if (dex_class_def == nullptr) {
// Generated classes have no class def.
return nullptr;
}
return dex_file.GetSourceFile(*dex_class_def);
}
std::string Class::GetLocation() {
ObjPtr<DexCache> dex_cache = GetDexCache();
if (dex_cache != nullptr && !IsProxyClass()) {
return dex_cache->GetLocation()->ToModifiedUtf8();
}
// Arrays and proxies are generated and have no corresponding dex file location.
return "generated class";
}
const dex::TypeList* Class::GetInterfaceTypeList() {
const dex::ClassDef* class_def = GetClassDef();
if (class_def == nullptr) {
return nullptr;
}
return GetDexFile().GetInterfacesList(*class_def);
}
void Class::PopulateEmbeddedVTable(PointerSize pointer_size) {
ObjPtr<PointerArray> table = GetVTableDuringLinking();
CHECK(table != nullptr) << PrettyClass();
const size_t table_length = table->GetLength();
SetEmbeddedVTableLength(table_length);
for (size_t i = 0; i < table_length; i++) {
SetEmbeddedVTableEntry(i, table->GetElementPtrSize<ArtMethod*>(i, pointer_size), pointer_size);
}
// Keep java.lang.Object class's vtable around for since it's easier
// to be reused by array classes during their linking.
if (!IsObjectClass()) {
SetVTable(nullptr);
}
}
class ReadBarrierOnNativeRootsVisitor {
public:
void operator()(ObjPtr<Object> obj ATTRIBUTE_UNUSED,
MemberOffset offset ATTRIBUTE_UNUSED,
bool is_static ATTRIBUTE_UNUSED) const {}
void VisitRootIfNonNull(CompressedReference<Object>* root) const
REQUIRES_SHARED(Locks::mutator_lock_) {
if (!root->IsNull()) {
VisitRoot(root);
}
}
void VisitRoot(CompressedReference<Object>* root) const
REQUIRES_SHARED(Locks::mutator_lock_) {
ObjPtr<Object> old_ref = root->AsMirrorPtr();
ObjPtr<Object> new_ref = ReadBarrier::BarrierForRoot(root);
if (old_ref != new_ref) {
// Update the field atomically. This may fail if mutator updates before us, but it's ok.
auto* atomic_root =
reinterpret_cast<Atomic<CompressedReference<Object>>*>(root);
atomic_root->CompareAndSetStrongSequentiallyConsistent(
CompressedReference<Object>::FromMirrorPtr(old_ref.Ptr()),
CompressedReference<Object>::FromMirrorPtr(new_ref.Ptr()));
}
}
};
// The pre-fence visitor for Class::CopyOf().
class CopyClassVisitor {
public:
CopyClassVisitor(Thread* self,
Handle<Class>* orig,
size_t new_length,
size_t copy_bytes,
ImTable* imt,
PointerSize pointer_size)
: self_(self), orig_(orig), new_length_(new_length),
copy_bytes_(copy_bytes), imt_(imt), pointer_size_(pointer_size) {
}
void operator()(ObjPtr<Object> obj, size_t usable_size ATTRIBUTE_UNUSED) const
REQUIRES_SHARED(Locks::mutator_lock_) {
StackHandleScope<1> hs(self_);
Handle<mirror::Class> h_new_class_obj(hs.NewHandle(obj->AsClass()));
Object::CopyObject(h_new_class_obj.Get(), orig_->Get(), copy_bytes_);
Class::SetStatus(h_new_class_obj, ClassStatus::kResolving, self_);
h_new_class_obj->PopulateEmbeddedVTable(pointer_size_);
h_new_class_obj->SetImt(imt_, pointer_size_);
h_new_class_obj->SetClassSize(new_length_);
// Visit all of the references to make sure there is no from space references in the native
// roots.
h_new_class_obj->Object::VisitReferences(ReadBarrierOnNativeRootsVisitor(), VoidFunctor());
}
private:
Thread* const self_;
Handle<Class>* const orig_;
const size_t new_length_;
const size_t copy_bytes_;
ImTable* imt_;
const PointerSize pointer_size_;
DISALLOW_COPY_AND_ASSIGN(CopyClassVisitor);
};
ObjPtr<Class> Class::CopyOf(Handle<Class> h_this,
Thread* self,
int32_t new_length,
ImTable* imt,
PointerSize pointer_size) {
DCHECK_GE(new_length, static_cast<int32_t>(sizeof(Class)));
// We may get copied by a compacting GC.
Runtime* runtime = Runtime::Current();
gc::Heap* heap = runtime->GetHeap();
// The num_bytes (3rd param) is sizeof(Class) as opposed to SizeOf()
// to skip copying the tail part that we will overwrite here.
CopyClassVisitor visitor(self, &h_this, new_length, sizeof(Class), imt, pointer_size);
ObjPtr<mirror::Class> java_lang_Class = GetClassRoot<mirror::Class>(runtime->GetClassLinker());
ObjPtr<Object> new_class = kMovingClasses ?
heap->AllocObject(self, java_lang_Class, new_length, visitor) :
heap->AllocNonMovableObject(self, java_lang_Class, new_length, visitor);
if (UNLIKELY(new_class == nullptr)) {
self->AssertPendingOOMException();
return nullptr;
}
return new_class->AsClass();
}
bool Class::ProxyDescriptorEquals(const char* match) {
DCHECK(IsProxyClass());
std::string storage;
const char* descriptor = GetDescriptor(&storage);
DCHECK(descriptor == storage.c_str());
return storage == match;
}
// TODO: Move this to java_lang_Class.cc?
ArtMethod* Class::GetDeclaredConstructor(
Thread* self, Handle<ObjectArray<Class>> args, PointerSize pointer_size) {
for (auto& m : GetDirectMethods(pointer_size)) {
// Skip <clinit> which is a static constructor, as well as non constructors.
if (m.IsStatic() || !m.IsConstructor()) {
continue;
}
// May cause thread suspension and exceptions.
if (m.GetInterfaceMethodIfProxy(kRuntimePointerSize)->EqualParameters(args)) {
return &m;
}
if (UNLIKELY(self->IsExceptionPending())) {
return nullptr;
}
}
return nullptr;
}
uint32_t Class::Depth() {
uint32_t depth = 0;
for (ObjPtr<Class> cls = this; cls->GetSuperClass() != nullptr; cls = cls->GetSuperClass()) {
depth++;
}
return depth;
}
dex::TypeIndex Class::FindTypeIndexInOtherDexFile(const DexFile& dex_file) {
std::string temp;
const dex::TypeId* type_id = dex_file.FindTypeId(GetDescriptor(&temp));
return (type_id == nullptr) ? dex::TypeIndex() : dex_file.GetIndexForTypeId(*type_id);
}
ALWAYS_INLINE
static bool IsMethodPreferredOver(ArtMethod* orig_method,
bool orig_method_hidden,
ArtMethod* new_method,
bool new_method_hidden) {
DCHECK(new_method != nullptr);
// Is this the first result?
if (orig_method == nullptr) {
return true;
}
// Original method is hidden, the new one is not?
if (orig_method_hidden && !new_method_hidden) {
return true;
}
// We iterate over virtual methods first and then over direct ones,
// so we can never be in situation where `orig_method` is direct and
// `new_method` is virtual.
DCHECK(!orig_method->IsDirect() || new_method->IsDirect());
// Original method is synthetic, the new one is not?
if (orig_method->IsSynthetic() && !new_method->IsSynthetic()) {
return true;
}
return false;
}
template <PointerSize kPointerSize>
ObjPtr<Method> Class::GetDeclaredMethodInternal(
Thread* self,
ObjPtr<Class> klass,
ObjPtr<String> name,
ObjPtr<ObjectArray<Class>> args,
const std::function<hiddenapi::AccessContext()>& fn_get_access_context) {
// Covariant return types (or smali) permit the class to define
// multiple methods with the same name and parameter types.
// Prefer (in decreasing order of importance):
// 1) non-hidden method over hidden
// 2) virtual methods over direct
// 3) non-synthetic methods over synthetic
// We never return miranda methods that were synthesized by the runtime.
StackHandleScope<3> hs(self);
auto h_method_name = hs.NewHandle(name);
if (UNLIKELY(h_method_name == nullptr)) {
ThrowNullPointerException("name == null");
return nullptr;
}
auto h_args = hs.NewHandle(args);
Handle<Class> h_klass = hs.NewHandle(klass);
constexpr hiddenapi::AccessMethod access_method = hiddenapi::AccessMethod::kNone;
ArtMethod* result = nullptr;
bool result_hidden = false;
for (auto& m : h_klass->GetDeclaredVirtualMethods(kPointerSize)) {
if (m.IsMiranda()) {
continue;
}
auto* np_method = m.GetInterfaceMethodIfProxy(kPointerSize);
// May cause thread suspension.
ObjPtr<String> np_name = np_method->ResolveNameString();
if (!np_name->Equals(h_method_name.Get()) || !np_method->EqualParameters(h_args)) {
if (UNLIKELY(self->IsExceptionPending())) {
return nullptr;
}
continue;
}
bool m_hidden = hiddenapi::ShouldDenyAccessToMember(&m, fn_get_access_context, access_method);
if (!m_hidden && !m.IsSynthetic()) {
// Non-hidden, virtual, non-synthetic. Best possible result, exit early.
return Method::CreateFromArtMethod<kPointerSize>(self, &m);
} else if (IsMethodPreferredOver(result, result_hidden, &m, m_hidden)) {
// Remember as potential result.
result = &m;
result_hidden = m_hidden;
}
}
if ((result != nullptr) && !result_hidden) {
// We have not found a non-hidden, virtual, non-synthetic method, but
// if we have found a non-hidden, virtual, synthetic method, we cannot
// do better than that later.
DCHECK(!result->IsDirect());
DCHECK(result->IsSynthetic());
} else {
for (auto& m : h_klass->GetDirectMethods(kPointerSize)) {
auto modifiers = m.GetAccessFlags();
if ((modifiers & kAccConstructor) != 0) {
continue;
}
auto* np_method = m.GetInterfaceMethodIfProxy(kPointerSize);
// May cause thread suspension.
ObjPtr<String> np_name = np_method->ResolveNameString();
if (np_name == nullptr) {
self->AssertPendingException();
return nullptr;
}
if (!np_name->Equals(h_method_name.Get()) || !np_method->EqualParameters(h_args)) {
if (UNLIKELY(self->IsExceptionPending())) {
return nullptr;
}
continue;
}
DCHECK(!m.IsMiranda()); // Direct methods cannot be miranda methods.
bool m_hidden = hiddenapi::ShouldDenyAccessToMember(&m, fn_get_access_context, access_method);
if (!m_hidden && !m.IsSynthetic()) {
// Non-hidden, direct, non-synthetic. Any virtual result could only have been
// hidden, therefore this is the best possible match. Exit now.
DCHECK((result == nullptr) || result_hidden);
return Method::CreateFromArtMethod<kPointerSize>(self, &m);
} else if (IsMethodPreferredOver(result, result_hidden, &m, m_hidden)) {
// Remember as potential result.
result = &m;
result_hidden = m_hidden;
}
}
}
return result != nullptr
? Method::CreateFromArtMethod<kPointerSize>(self, result)
: nullptr;
}
template
ObjPtr<Method> Class::GetDeclaredMethodInternal<PointerSize::k32>(
Thread* self,
ObjPtr<Class> klass,
ObjPtr<String> name,
ObjPtr<ObjectArray<Class>> args,
const std::function<hiddenapi::AccessContext()>& fn_get_access_context);
template
ObjPtr<Method> Class::GetDeclaredMethodInternal<PointerSize::k64>(
Thread* self,
ObjPtr<Class> klass,
ObjPtr<String> name,
ObjPtr<ObjectArray<Class>> args,
const std::function<hiddenapi::AccessContext()>& fn_get_access_context);
template <PointerSize kPointerSize>
ObjPtr<Constructor> Class::GetDeclaredConstructorInternal(
Thread* self,
ObjPtr<Class> klass,
ObjPtr<ObjectArray<Class>> args) {
StackHandleScope<1> hs(self);
ArtMethod* result = klass->GetDeclaredConstructor(self, hs.NewHandle(args), kPointerSize);
return result != nullptr
? Constructor::CreateFromArtMethod<kPointerSize>(self, result)
: nullptr;
}
// Constructor::CreateFromArtMethod<kTransactionActive>(self, result)
template
ObjPtr<Constructor> Class::GetDeclaredConstructorInternal<PointerSize::k32>(
Thread* self,
ObjPtr<Class> klass,
ObjPtr<ObjectArray<Class>> args);
template
ObjPtr<Constructor> Class::GetDeclaredConstructorInternal<PointerSize::k64>(
Thread* self,
ObjPtr<Class> klass,
ObjPtr<ObjectArray<Class>> args);
int32_t Class::GetInnerClassFlags(Handle<Class> h_this, int32_t default_value) {
if (h_this->IsProxyClass() || h_this->GetDexCache() == nullptr) {
return default_value;
}
uint32_t flags;
if (!annotations::GetInnerClassFlags(h_this, &flags)) {
return default_value;
}
return flags;
}
void Class::SetObjectSizeAllocFastPath(uint32_t new_object_size) {
if (Runtime::Current()->IsActiveTransaction()) {
SetField32Volatile<true>(ObjectSizeAllocFastPathOffset(), new_object_size);
} else {
SetField32Volatile<false>(ObjectSizeAllocFastPathOffset(), new_object_size);
}
}
std::string Class::PrettyDescriptor(ObjPtr<mirror::Class> klass) {
if (klass == nullptr) {
return "null";
}
return klass->PrettyDescriptor();
}
std::string Class::PrettyDescriptor() {
std::string temp;
return art::PrettyDescriptor(GetDescriptor(&temp));
}
std::string Class::PrettyClass(ObjPtr<mirror::Class> c) {
if (c == nullptr) {
return "null";
}
return c->PrettyClass();
}
std::string Class::PrettyClass() {
std::string result;
if (IsObsoleteObject()) {
result += "(Obsolete)";
}
if (IsRetired()) {
result += "(Retired)";
}
result += "java.lang.Class<";
result += PrettyDescriptor();
result += ">";
return result;
}
std::string Class::PrettyClassAndClassLoader(ObjPtr<mirror::Class> c) {
if (c == nullptr) {
return "null";
}
return c->PrettyClassAndClassLoader();
}
std::string Class::PrettyClassAndClassLoader() {
std::string result;
result += "java.lang.Class<";
result += PrettyDescriptor();
result += ",";
result += mirror::Object::PrettyTypeOf(GetClassLoader());
// TODO: add an identifying hash value for the loader
result += ">";
return result;
}
template<VerifyObjectFlags kVerifyFlags> void Class::GetAccessFlagsDCheck() {
// Check class is loaded/retired or this is java.lang.String that has a
// circularity issue during loading the names of its members
DCHECK(IsIdxLoaded<kVerifyFlags>() || IsRetired<kVerifyFlags>() ||
IsErroneous<static_cast<VerifyObjectFlags>(kVerifyFlags & ~kVerifyThis)>() ||
this == GetClassRoot<String>())
<< "IsIdxLoaded=" << IsIdxLoaded<kVerifyFlags>()
<< " IsRetired=" << IsRetired<kVerifyFlags>()
<< " IsErroneous=" <<
IsErroneous<static_cast<VerifyObjectFlags>(kVerifyFlags & ~kVerifyThis)>()
<< " IsString=" << (this == GetClassRoot<String>())
<< " status= " << GetStatus<kVerifyFlags>()
<< " descriptor=" << PrettyDescriptor();
}
// Instantiate the common cases.
template void Class::GetAccessFlagsDCheck<kVerifyNone>();
template void Class::GetAccessFlagsDCheck<kVerifyThis>();
template void Class::GetAccessFlagsDCheck<kVerifyReads>();
template void Class::GetAccessFlagsDCheck<kVerifyWrites>();
template void Class::GetAccessFlagsDCheck<kVerifyAll>();
void Class::SetAccessFlagsDCheck(uint32_t new_access_flags) {
uint32_t old_access_flags = GetField32<kVerifyNone>(AccessFlagsOffset());
// kAccVerificationAttempted is retained.
CHECK((old_access_flags & kAccVerificationAttempted) == 0 ||
(new_access_flags & kAccVerificationAttempted) != 0);
}
ObjPtr<Object> Class::GetMethodIds() {
ObjPtr<ClassExt> ext(GetExtData());
if (ext.IsNull()) {
return nullptr;
} else {
return ext->GetJMethodIDs();
}
}
bool Class::EnsureMethodIds(Handle<Class> h_this) {
DCHECK_NE(Runtime::Current()->GetJniIdType(), JniIdType::kPointer) << "JNI Ids are pointers!";
Thread* self = Thread::Current();
ObjPtr<ClassExt> ext(EnsureExtDataPresent(h_this, self));
if (ext.IsNull()) {
self->AssertPendingOOMException();
return false;
}
return ext->EnsureJMethodIDsArrayPresent(h_this->NumMethods());
}
ObjPtr<Object> Class::GetStaticFieldIds() {
ObjPtr<ClassExt> ext(GetExtData());
if (ext.IsNull()) {
return nullptr;
} else {
return ext->GetStaticJFieldIDs();
}
}
bool Class::EnsureStaticFieldIds(Handle<Class> h_this) {
DCHECK_NE(Runtime::Current()->GetJniIdType(), JniIdType::kPointer) << "JNI Ids are pointers!";
Thread* self = Thread::Current();
ObjPtr<ClassExt> ext(EnsureExtDataPresent(h_this, self));
if (ext.IsNull()) {
self->AssertPendingOOMException();
return false;
}
return ext->EnsureStaticJFieldIDsArrayPresent(h_this->NumStaticFields());
}
ObjPtr<Object> Class::GetInstanceFieldIds() {
ObjPtr<ClassExt> ext(GetExtData());
if (ext.IsNull()) {
return nullptr;
} else {
return ext->GetInstanceJFieldIDs();
}
}
bool Class::EnsureInstanceFieldIds(Handle<Class> h_this) {
DCHECK_NE(Runtime::Current()->GetJniIdType(), JniIdType::kPointer) << "JNI Ids are pointers!";
Thread* self = Thread::Current();
ObjPtr<ClassExt> ext(EnsureExtDataPresent(h_this, self));
if (ext.IsNull()) {
self->AssertPendingOOMException();
return false;
}
return ext->EnsureInstanceJFieldIDsArrayPresent(h_this->NumInstanceFields());
}
size_t Class::GetStaticFieldIdOffset(ArtField* field) {
DCHECK_LT(reinterpret_cast<uintptr_t>(field),
reinterpret_cast<uintptr_t>(&*GetSFieldsPtr()->end()))
<< "field not part of the current class. " << field->PrettyField() << " class is "
<< PrettyClass();
DCHECK_GE(reinterpret_cast<uintptr_t>(field),
reinterpret_cast<uintptr_t>(&*GetSFieldsPtr()->begin()))
<< "field not part of the current class. " << field->PrettyField() << " class is "
<< PrettyClass();
uintptr_t start = reinterpret_cast<uintptr_t>(&GetSFieldsPtr()->At(0));
uintptr_t fld = reinterpret_cast<uintptr_t>(field);
size_t res = (fld - start) / sizeof(ArtField);
DCHECK_EQ(&GetSFieldsPtr()->At(res), field)
<< "Incorrect field computation expected: " << field->PrettyField()
<< " got: " << GetSFieldsPtr()->At(res).PrettyField();
return res;
}
size_t Class::GetInstanceFieldIdOffset(ArtField* field) {
DCHECK_LT(reinterpret_cast<uintptr_t>(field),
reinterpret_cast<uintptr_t>(&*GetIFieldsPtr()->end()))
<< "field not part of the current class. " << field->PrettyField() << " class is "
<< PrettyClass();
DCHECK_GE(reinterpret_cast<uintptr_t>(field),
reinterpret_cast<uintptr_t>(&*GetIFieldsPtr()->begin()))
<< "field not part of the current class. " << field->PrettyField() << " class is "
<< PrettyClass();
uintptr_t start = reinterpret_cast<uintptr_t>(&GetIFieldsPtr()->At(0));
uintptr_t fld = reinterpret_cast<uintptr_t>(field);
size_t res = (fld - start) / sizeof(ArtField);
DCHECK_EQ(&GetIFieldsPtr()->At(res), field)
<< "Incorrect field computation expected: " << field->PrettyField()
<< " got: " << GetIFieldsPtr()->At(res).PrettyField();
return res;
}
size_t Class::GetMethodIdOffset(ArtMethod* method, PointerSize pointer_size) {
DCHECK(GetMethodsSlice(kRuntimePointerSize).Contains(method))
<< "method not part of the current class. " << method->PrettyMethod() << "( " << reinterpret_cast<void*>(method) << ")" << " class is "
<< PrettyClass() << [&]() REQUIRES_SHARED(Locks::mutator_lock_) {
std::ostringstream os;
os << " Methods are [";
for (ArtMethod& m : GetMethodsSlice(kRuntimePointerSize)) {
os << m.PrettyMethod() << "( " << reinterpret_cast<void*>(&m) << "), ";
}
os << "]";
return os.str();
}();
uintptr_t start = reinterpret_cast<uintptr_t>(&*GetMethodsSlice(pointer_size).begin());
uintptr_t fld = reinterpret_cast<uintptr_t>(method);
size_t art_method_size = ArtMethod::Size(pointer_size);
size_t art_method_align = ArtMethod::Alignment(pointer_size);
size_t res = (fld - start) / art_method_size;
DCHECK_EQ(&GetMethodsPtr()->At(res, art_method_size, art_method_align), method)
<< "Incorrect method computation expected: " << method->PrettyMethod()
<< " got: " << GetMethodsPtr()->At(res, art_method_size, art_method_align).PrettyMethod();
return res;
}
ArtMethod* Class::FindAccessibleInterfaceMethod(ArtMethod* implementation_method,
PointerSize pointer_size)
REQUIRES_SHARED(Locks::mutator_lock_) {
ObjPtr<mirror::IfTable> iftable = GetIfTable();
for (int32_t i = 0, iftable_count = iftable->Count(); i < iftable_count; ++i) {
ObjPtr<mirror::PointerArray> methods = iftable->GetMethodArrayOrNull(i);
if (methods == nullptr) {
continue;
}
for (size_t j = 0, count = iftable->GetMethodArrayCount(i); j < count; ++j) {
if (implementation_method == methods->GetElementPtrSize<ArtMethod*>(j, pointer_size)) {
ObjPtr<mirror::Class> iface = iftable->GetInterface(i);
ArtMethod* interface_method = &iface->GetVirtualMethodsSlice(pointer_size)[j];
// If the interface method is part of the public SDK, return it.
if ((hiddenapi::GetRuntimeFlags(interface_method) & kAccPublicApi) != 0) {
return interface_method;
}
}
}
}
return nullptr;
}
} // namespace mirror
} // namespace art