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android / platform / art / f7e85a5 / . / src / class_linker.cc
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// Copyright 2011 Google Inc. All Rights Reserved.
// Author: cshapiro@google.com (Carl Shapiro)
#include "class_linker.h"
#include <vector>
#include <utility>
#include "casts.h"
#include "dex_cache.h"
#include "dex_verifier.h"
#include "heap.h"
#include "logging.h"
#include "monitor.h"
#include "object.h"
#include "dex_file.h"
#include "scoped_ptr.h"
#include "thread.h"
#include "utils.h"
namespace art {
ClassLinker* ClassLinker::Create(const std::vector<DexFile*>& boot_class_path) {
scoped_ptr<ClassLinker> class_linker(new ClassLinker);
class_linker->Init(boot_class_path);
// TODO: check for failure during initialization
return class_linker.release();
}
void ClassLinker::Init(const std::vector<DexFile*>& boot_class_path) {
init_done_ = false;
// java_lang_Class comes first, its needed for AllocClass
Class* java_lang_Class = down_cast<Class*>(Heap::AllocObject(NULL, sizeof(Class)));
CHECK(java_lang_Class != NULL);
java_lang_Class->descriptor_ = "Ljava/lang/Class;";
java_lang_Class->object_size_ = sizeof(Class);
java_lang_Class->klass_ = java_lang_Class;
// AllocClass(Class*) can now be used
// java_lang_Object comes next so that object_array_class can be created
Class* java_lang_Object = AllocClass(java_lang_Class);
CHECK(java_lang_Object != NULL);
java_lang_Object->descriptor_ = "Ljava/lang/Object;";
// backfill Object as the super class of Class
java_lang_Class->super_class_ = java_lang_Object;
// object_array_class is for root_classes to provide the storage for these classes
Class* object_array_class = AllocClass(java_lang_Class);
CHECK(object_array_class != NULL);
// string is necessary so that FindClass can assigning names to members
Class* java_lang_String = AllocClass(java_lang_Class);
CHECK(java_lang_String != NULL);
java_lang_String->object_size_ = sizeof(String);
// create storage for root classes, save away our work so far
class_roots_ = ObjectArray<Class>::Alloc(object_array_class, kClassRootsMax);
class_roots_->Set(kJavaLangClass, java_lang_Class);
class_roots_->Set(kJavaLangObject, java_lang_Object);
class_roots_->Set(kObjectArrayClass, object_array_class);
class_roots_->Set(kJavaLangString, java_lang_String);
// now that these are registered, we can use AllocClass() and AllocObjectArray
// setup boot_class_path_ now that we can use AllocObjectArray to
// DexCache instances
for (size_t i = 0; i != boot_class_path.size(); ++i) {
AppendToBootClassPath(boot_class_path[i]);
}
// now we can use FindSystemClass, at least for non-arrays classes.
// run Object and Class to setup their dex_cache_ fields and register them in classes_.
// we also override their object_size_ values to accommodate the extra C++ fields.
Class* Object_class = FindSystemClass(java_lang_Object->GetDescriptor());
CHECK_EQ(java_lang_Object, Object_class);
CHECK_LE(java_lang_Object->object_size_, sizeof(Object));
java_lang_Object->object_size_ = sizeof(Object);
Class* Class_class = FindSystemClass(java_lang_Class->GetDescriptor());
CHECK_EQ(java_lang_Class, Class_class);
CHECK_LE(java_lang_Class->object_size_, sizeof(Class));
java_lang_Class->object_size_ = sizeof(Class);
// set special sizes for these C++ extended classes (Field, Method, String).
// we also remember them in class_roots_ to construct them within ClassLinker
Class* java_lang_reflect_Field = FindSystemClass("Ljava/lang/reflect/Field;");
CHECK(java_lang_reflect_Field != NULL);
CHECK_LE(java_lang_reflect_Field->object_size_, std::max(sizeof(StaticField), sizeof(InstanceField)));
java_lang_reflect_Field->object_size_ = std::max(sizeof(StaticField), sizeof(InstanceField));
class_roots_->Set(kJavaLangReflectField, java_lang_reflect_Field);
Class* java_lang_reflect_Method = FindSystemClass("Ljava/lang/reflect/Method;");
CHECK(java_lang_reflect_Method != NULL);
CHECK_LE(java_lang_reflect_Method->object_size_, sizeof(Method));
java_lang_reflect_Method->object_size_ = sizeof(Method);
class_roots_->Set(kJavaLangReflectMethod, java_lang_reflect_Method);
Class* String_class = FindSystemClass("Ljava/lang/String;");
CHECK_EQ(java_lang_String, String_class);
CHECK_EQ(java_lang_String->object_size_, sizeof(String));
java_lang_String->object_size_ = sizeof(String);
class_roots_->Set(kJavaLangString, java_lang_String);
// Setup a single, global copy of "interfaces" and "iftable" for
// reuse across array classes
Class* java_lang_Cloneable = AllocClass();
CHECK(java_lang_Cloneable != NULL);
java_lang_Cloneable->descriptor_ = "Ljava/lang/Cloneable;";
Class* java_io_Serializable = AllocClass();
CHECK(java_io_Serializable != NULL);
java_io_Serializable->descriptor_ = "Ljava/io/Serializable;";
array_interfaces_ = AllocObjectArray<Class>(2);
CHECK(array_interfaces_ != NULL);
array_interfaces_->Set(0, java_lang_Cloneable);
array_interfaces_->Set(1, java_io_Serializable);
// We assume that Cloneable/Serializable don't have superinterfaces --
// normally we'd have to crawl up and explicitly list all of the
// supers as well. These interfaces don't have any methods, so we
// don't have to worry about the ifviPool either.
array_iftable_ = new InterfaceEntry[2];
CHECK(array_iftable_ != NULL);
memset(array_iftable_, 0, sizeof(InterfaceEntry) * 2);
array_iftable_[0].SetClass(array_interfaces_->Get(0));
array_iftable_[1].SetClass(array_interfaces_->Get(1));
// now FindClass can be used for non-primitive array classes
// run Object[] through FindClass to complete initialization
Class* Object_array_class = FindSystemClass("[Ljava/lang/Object;");
CHECK_EQ(object_array_class, Object_array_class);
// Setup the primitive type classes.
class_roots_->Set(kPrimitiveByte, CreatePrimitiveClass("B"));
class_roots_->Set(kPrimitiveChar, CreatePrimitiveClass("C"));
class_roots_->Set(kPrimitiveDouble, CreatePrimitiveClass("D"));
class_roots_->Set(kPrimitiveFloat, CreatePrimitiveClass("F"));
class_roots_->Set(kPrimitiveInt, CreatePrimitiveClass("I"));
class_roots_->Set(kPrimitiveLong, CreatePrimitiveClass("J"));
class_roots_->Set(kPrimitiveShort, CreatePrimitiveClass("S"));
class_roots_->Set(kPrimitiveBoolean, CreatePrimitiveClass("Z"));
class_roots_->Set(kPrimitiveVoid, CreatePrimitiveClass("V"));
// now we can use FindSystemClass for anything, including for "[C"
Class* char_array = FindSystemClass("[C");
class_roots_->Set(kCharArrayClass, char_array);
String::InitClasses(java_lang_String, char_array);
// Now AllocString* can be used
// ensure all class_roots_ were initialized
for (size_t i = 0; i < kClassRootsMax; i++) {
CHECK(class_roots_->Get(i) != NULL);
}
// disable the slow paths in FindClass and CreatePrimitiveClass now
// that Object, Class, and Object[] are setup
init_done_ = true;
}
void ClassLinker::VisitRoots(RootVistor* root_visitor, void* arg) {
root_visitor(class_roots_, arg);
for (size_t i = 0; i < dex_caches_.size(); i++) {
root_visitor(dex_caches_[i], arg);
}
// TODO: acquire classes_lock_
typedef Table::const_iterator It; // TODO: C++0x auto
for (It it = classes_.begin(), end = classes_.end(); it != end; ++it) {
root_visitor(it->second, arg);
}
// TODO: release classes_lock_
root_visitor(array_interfaces_, arg);
}
DexCache* ClassLinker::AllocDexCache() {
return down_cast<DexCache*>(AllocObjectArray<Object>(DexCache::kMax));
}
Class* ClassLinker::AllocClass(Class* java_lang_Class) {
return down_cast<Class*>(Object::Alloc(java_lang_Class));
}
Class* ClassLinker::AllocClass() {
return AllocClass(class_roots_->Get(kJavaLangClass));
}
StaticField* ClassLinker::AllocStaticField() {
return down_cast<StaticField*>(Heap::AllocObject(class_roots_->Get(kJavaLangReflectField),
sizeof(StaticField)));
}
InstanceField* ClassLinker::AllocInstanceField() {
return down_cast<InstanceField*>(Heap::AllocObject(class_roots_->Get(kJavaLangReflectField),
sizeof(InstanceField)));
}
Method* ClassLinker::AllocMethod() {
return down_cast<Method*>(Heap::AllocObject(class_roots_->Get(kJavaLangReflectMethod),
sizeof(Method)));
}
String* ClassLinker::AllocStringFromModifiedUtf8(int32_t utf16_length,
const char* utf8_data_in) {
return String::AllocFromModifiedUtf8(class_roots_->Get(kJavaLangString),
class_roots_->Get(kCharArrayClass),
utf16_length,
utf8_data_in);
}
Class* ClassLinker::FindClass(const StringPiece& descriptor,
Object* class_loader,
const DexFile* dex_file) {
Thread* self = Thread::Current();
DCHECK(self != NULL);
CHECK(!self->IsExceptionPending());
// Find the class in the loaded classes table.
Class* klass = LookupClass(descriptor, class_loader);
if (klass == NULL) {
// Class is not yet loaded.
if (descriptor[0] == '[') {
return CreateArrayClass(descriptor, class_loader, dex_file);
}
ClassPathEntry pair;
if (dex_file == NULL) {
pair = FindInBootClassPath(descriptor);
} else {
pair.first = dex_file;
pair.second = dex_file->FindClassDef(descriptor);
}
if (pair.second == NULL) {
LG << "Class " << descriptor << " not found"; // TODO: NoClassDefFoundError
return NULL;
}
const DexFile* dex_file = pair.first;
const DexFile::ClassDef* dex_class_def = pair.second;
DexCache* dex_cache = FindDexCache(dex_file);
// Load the class from the dex file.
if (!init_done_) {
// finish up init of hand crafted class_roots_
if (descriptor == "Ljava/lang/Object;") {
klass = class_roots_->Get(kJavaLangObject);
} else if (descriptor == "Ljava/lang/Class;") {
klass = class_roots_->Get(kJavaLangClass);
} else if (descriptor == "Ljava/lang/String;") {
klass = class_roots_->Get(kJavaLangString);
} else {
klass = AllocClass();
}
} else {
klass = AllocClass();
}
klass->dex_cache_ = dex_cache;
LoadClass(*dex_file, *dex_class_def, klass);
// Check for a pending exception during load
if (self->IsExceptionPending()) {
// TODO: free native allocations in klass
return NULL;
}
{
ObjectLock lock(klass);
klass->clinit_thread_id_ = self->GetId();
// Add the newly loaded class to the loaded classes table.
bool success = InsertClass(klass);
if (!success) {
// We may fail to insert if we raced with another thread.
klass->clinit_thread_id_ = 0;
// TODO: free native allocations in klass
klass = LookupClass(descriptor, class_loader);
CHECK(klass != NULL);
} else {
// Link the class.
if (!LinkClass(klass, dex_file)) {
// Linking failed.
// TODO: CHECK(self->IsExceptionPending());
lock.NotifyAll();
return NULL;
}
}
}
}
// Link the class if it has not already been linked.
if (!klass->IsLinked() && !klass->IsErroneous()) {
ObjectLock lock(klass);
// Check for circular dependencies between classes.
if (!klass->IsLinked() && klass->clinit_thread_id_ == self->GetId()) {
LG << "Recursive link"; // TODO: ClassCircularityError
return NULL;
}
// Wait for the pending initialization to complete.
while (!klass->IsLinked() && !klass->IsErroneous()) {
lock.Wait();
}
}
if (klass->IsErroneous()) {
LG << "EarlierClassFailure"; // TODO: EarlierClassFailure
return NULL;
}
// Return the loaded class. No exceptions should be pending.
CHECK(!self->IsExceptionPending());
return klass;
}
void ClassLinker::LoadClass(const DexFile& dex_file,
const DexFile::ClassDef& dex_class_def,
Class* klass) {
CHECK(klass != NULL);
CHECK(klass->dex_cache_ != NULL);
const byte* class_data = dex_file.GetClassData(dex_class_def);
DexFile::ClassDataHeader header = dex_file.ReadClassDataHeader(&class_data);
const char* descriptor = dex_file.GetClassDescriptor(dex_class_def);
CHECK(descriptor != NULL);
klass->klass_ = class_roots_->Get(kJavaLangClass);
klass->descriptor_.set(descriptor);
klass->descriptor_alloc_ = NULL;
klass->access_flags_ = dex_class_def.access_flags_;
klass->class_loader_ = NULL; // TODO
klass->primitive_type_ = Class::kPrimNot;
klass->status_ = Class::kStatusIdx;
klass->super_class_ = NULL;
klass->super_class_idx_ = dex_class_def.superclass_idx_;
size_t num_static_fields = header.static_fields_size_;
size_t num_instance_fields = header.instance_fields_size_;
size_t num_direct_methods = header.direct_methods_size_;
size_t num_virtual_methods = header.virtual_methods_size_;
klass->source_file_ = dex_file.dexGetSourceFile(dex_class_def);
// Load class interfaces.
LoadInterfaces(dex_file, dex_class_def, klass);
// Load static fields.
DCHECK(klass->sfields_ == NULL);
if (num_static_fields != 0) {
klass->sfields_ = AllocObjectArray<StaticField>(num_static_fields);
uint32_t last_idx = 0;
for (size_t i = 0; i < klass->NumStaticFields(); ++i) {
DexFile::Field dex_field;
dex_file.dexReadClassDataField(&class_data, &dex_field, &last_idx);
StaticField* sfield = AllocStaticField();
klass->SetStaticField(i, sfield);
LoadField(dex_file, dex_field, klass, sfield);
}
}
// Load instance fields.
DCHECK(klass->ifields_ == NULL);
if (num_instance_fields != 0) {
// TODO: allocate on the object heap.
klass->ifields_ = AllocObjectArray<InstanceField>(num_instance_fields);
uint32_t last_idx = 0;
for (size_t i = 0; i < klass->NumInstanceFields(); ++i) {
DexFile::Field dex_field;
dex_file.dexReadClassDataField(&class_data, &dex_field, &last_idx);
InstanceField* ifield = AllocInstanceField();
klass->SetInstanceField(i, ifield);
LoadField(dex_file, dex_field, klass, ifield);
}
}
// Load direct methods.
DCHECK(klass->direct_methods_ == NULL);
if (num_direct_methods != 0) {
// TODO: append direct methods to class object
klass->direct_methods_ = AllocObjectArray<Method>(num_direct_methods);
uint32_t last_idx = 0;
for (size_t i = 0; i < klass->NumDirectMethods(); ++i) {
DexFile::Method dex_method;
dex_file.dexReadClassDataMethod(&class_data, &dex_method, &last_idx);
Method* meth = AllocMethod();
klass->SetDirectMethod(i, meth);
LoadMethod(dex_file, dex_method, klass, meth);
// TODO: register maps
}
}
// Load virtual methods.
DCHECK(klass->virtual_methods_ == NULL);
if (num_virtual_methods != 0) {
// TODO: append virtual methods to class object
klass->virtual_methods_ = AllocObjectArray<Method>(num_virtual_methods);
uint32_t last_idx = 0;
for (size_t i = 0; i < klass->NumVirtualMethods(); ++i) {
DexFile::Method dex_method;
dex_file.dexReadClassDataMethod(&class_data, &dex_method, &last_idx);
Method* meth = AllocMethod();
klass->SetVirtualMethod(i, meth);
LoadMethod(dex_file, dex_method, klass, meth);
// TODO: register maps
}
}
}
void ClassLinker::LoadInterfaces(const DexFile& dex_file,
const DexFile::ClassDef& dex_class_def,
Class* klass) {
const DexFile::TypeList* list = dex_file.GetInterfacesList(dex_class_def);
if (list != NULL) {
DCHECK(klass->interfaces_ == NULL);
klass->interfaces_ = AllocObjectArray<Class>(list->Size());
DCHECK(klass->interfaces_idx_ == NULL);
klass->interfaces_idx_ = new uint32_t[list->Size()];
for (size_t i = 0; i < list->Size(); ++i) {
const DexFile::TypeItem& type_item = list->GetTypeItem(i);
klass->interfaces_idx_[i] = type_item.type_idx_;
}
}
}
void ClassLinker::LoadField(const DexFile& dex_file,
const DexFile::Field& src,
Class* klass,
Field* dst) {
const DexFile::FieldId& field_id = dex_file.GetFieldId(src.field_idx_);
dst->klass_ = klass;
dst->java_name_ = ResolveString(klass, field_id.name_idx_);
dst->descriptor_.set(dex_file.dexStringByTypeIdx(field_id.type_idx_));
dst->access_flags_ = src.access_flags_;
}
void ClassLinker::LoadMethod(const DexFile& dex_file,
const DexFile::Method& src,
Class* klass,
Method* dst) {
const DexFile::MethodId& method_id = dex_file.GetMethodId(src.method_idx_);
dst->klass_ = klass;
dst->java_name_ = ResolveString(klass, method_id.name_idx_);
dst->proto_idx_ = method_id.proto_idx_;
dst->shorty_.set(dex_file.GetShorty(method_id.proto_idx_));
dst->access_flags_ = src.access_flags_;
// TODO: check for finalize method
const DexFile::CodeItem* code_item = dex_file.GetCodeItem(src);
if (code_item != NULL) {
dst->num_registers_ = code_item->registers_size_;
dst->num_ins_ = code_item->ins_size_;
dst->num_outs_ = code_item->outs_size_;
dst->insns_ = code_item->insns_;
} else {
uint16_t num_args = dst->NumArgRegisters();
if (!dst->IsStatic()) {
++num_args;
}
dst->num_registers_ = dst->num_ins_ + num_args;
// TODO: native methods
}
}
ClassLinker::ClassPathEntry ClassLinker::FindInBootClassPath(const StringPiece& descriptor) {
for (size_t i = 0; i != boot_class_path_.size(); ++i) {
const DexFile* dex_file = boot_class_path_[i];
const DexFile::ClassDef* dex_class_def = dex_file->FindClassDef(descriptor);
if (dex_class_def != NULL) {
return ClassPathEntry(dex_file, dex_class_def);
}
}
return ClassPathEntry(NULL, NULL);
}
void ClassLinker::AppendToBootClassPath(DexFile* dex_file) {
CHECK(dex_file != NULL);
boot_class_path_.push_back(dex_file);
RegisterDexFile(dex_file);
}
void ClassLinker::RegisterDexFile(const DexFile* dex_file) {
CHECK(dex_file != NULL);
dex_files_.push_back(dex_file);
DexCache* dex_cache = AllocDexCache();
CHECK(dex_cache != NULL);
dex_cache->Init(AllocObjectArray<String>(dex_file->NumStringIds()),
AllocObjectArray<Class>(dex_file->NumTypeIds()),
AllocObjectArray<Method>(dex_file->NumMethodIds()),
AllocObjectArray<Field>(dex_file->NumFieldIds()));
dex_caches_.push_back(dex_cache);
}
const DexFile* ClassLinker::FindDexFile(const DexCache* dex_cache) const {
CHECK(dex_cache != NULL);
for (size_t i = 0; i != dex_caches_.size(); ++i) {
if (dex_caches_[i] == dex_cache) {
return dex_files_[i];
}
}
CHECK(false) << "Could not find DexFile";
return NULL;
}
DexCache* ClassLinker::FindDexCache(const DexFile* dex_file) const {
CHECK(dex_file != NULL);
for (size_t i = 0; i != dex_files_.size(); ++i) {
if (dex_files_[i] == dex_file) {
return dex_caches_[i];
}
}
CHECK(false) << "Could not find DexCache";
return NULL;
}
Class* ClassLinker::CreatePrimitiveClass(const StringPiece& descriptor) {
Class* klass = AllocClass();
CHECK(klass != NULL);
klass->super_class_ = NULL;
klass->access_flags_ = kAccPublic | kAccFinal | kAccAbstract;
klass->descriptor_ = descriptor;
klass->descriptor_alloc_ = NULL;
klass->status_ = Class::kStatusInitialized;
bool success = InsertClass(klass);
CHECK(success) << "CreatePrimitiveClass(" << descriptor << ") failed";
return klass;
}
// Create an array class (i.e. the class object for the array, not the
// array itself). "descriptor" looks like "[C" or "[[[[B" or
// "[Ljava/lang/String;".
//
// If "descriptor" refers to an array of primitives, look up the
// primitive type's internally-generated class object.
//
// "loader" is the class loader of the class that's referring to us. It's
// used to ensure that we're looking for the element type in the right
// context. It does NOT become the class loader for the array class; that
// always comes from the base element class.
//
// Returns NULL with an exception raised on failure.
Class* ClassLinker::CreateArrayClass(const StringPiece& descriptor,
Object* class_loader,
const DexFile* dex_file)
{
CHECK(descriptor[0] == '[');
// Identify the underlying element class and the array dimension depth.
Class* component_type_ = NULL;
int array_rank;
if (descriptor[1] == '[') {
// array of arrays; keep descriptor and grab stuff from parent
Class* outer = FindClass(descriptor.substr(1), class_loader, dex_file);
if (outer != NULL) {
// want the base class, not "outer", in our component_type_
component_type_ = outer->component_type_;
array_rank = outer->array_rank_ + 1;
} else {
DCHECK(component_type_ == NULL); // make sure we fail
}
} else {
array_rank = 1;
if (descriptor[1] == 'L') {
// array of objects; strip off "[" and look up descriptor.
const StringPiece subDescriptor = descriptor.substr(1);
component_type_ = FindClass(subDescriptor, class_loader, dex_file);
} else {
// array of a primitive type
component_type_ = FindPrimitiveClass(descriptor[1]);
}
}
if (component_type_ == NULL) {
// failed
// DCHECK(Thread::Current()->IsExceptionPending()); // TODO
return NULL;
}
// See if the component type is already loaded. Array classes are
// always associated with the class loader of their underlying
// element type -- an array of Strings goes with the loader for
// java/lang/String -- so we need to look for it there. (The
// caller should have checked for the existence of the class
// before calling here, but they did so with *their* class loader,
// not the component type's loader.)
//
// If we find it, the caller adds "loader" to the class' initiating
// loader list, which should prevent us from going through this again.
//
// This call is unnecessary if "loader" and "component_type_->class_loader_"
// are the same, because our caller (FindClass) just did the
// lookup. (Even if we get this wrong we still have correct behavior,
// because we effectively do this lookup again when we add the new
// class to the hash table --- necessary because of possible races with
// other threads.)
if (class_loader != component_type_->class_loader_) {
Class* new_class = LookupClass(descriptor, component_type_->class_loader_);
if (new_class != NULL) {
return new_class;
}
}
// Fill out the fields in the Class.
//
// It is possible to execute some methods against arrays, because
// all arrays are subclasses of java_lang_Object_, so we need to set
// up a vtable. We can just point at the one in java_lang_Object_.
//
// Array classes are simple enough that we don't need to do a full
// link step.
Class* new_class = NULL;
if (!init_done_ && descriptor == "[Ljava/lang/Object;") {
new_class = class_roots_->Get(kObjectArrayClass);
CHECK(new_class);
}
if (new_class == NULL) {
new_class = AllocClass();
if (new_class == NULL) {
return NULL;
}
}
new_class->descriptor_alloc_ = new std::string(descriptor.data(),
descriptor.size());
new_class->descriptor_.set(new_class->descriptor_alloc_->data(),
new_class->descriptor_alloc_->size());
Class* java_lang_Object = class_roots_->Get(kJavaLangObject);
new_class->super_class_ = java_lang_Object;
new_class->vtable_ = java_lang_Object->vtable_;
new_class->primitive_type_ = Class::kPrimNot;
new_class->component_type_ = component_type_;
new_class->class_loader_ = component_type_->class_loader_;
new_class->array_rank_ = array_rank;
new_class->status_ = Class::kStatusInitialized;
// don't need to set new_class->object_size_
// All arrays have java/lang/Cloneable and java/io/Serializable as
// interfaces. We need to set that up here, so that stuff like
// "instanceof" works right.
//
// Note: The GC could run during the call to FindSystemClass,
// so we need to make sure the class object is GC-valid while we're in
// there. Do this by clearing the interface list so the GC will just
// think that the entries are null.
// Use the single, global copies of "interfaces" and "iftable"
// (remember not to free them for arrays).
DCHECK(array_interfaces_ != NULL);
new_class->interfaces_ = array_interfaces_;
new_class->iftable_count_ = 2;
DCHECK(array_iftable_ != NULL);
new_class->iftable_ = array_iftable_;
// Inherit access flags from the component type. Arrays can't be
// used as a superclass or interface, so we want to add "final"
// and remove "interface".
//
// Don't inherit any non-standard flags (e.g., kAccFinal)
// from component_type_. We assume that the array class does not
// override finalize().
new_class->access_flags_ = ((new_class->component_type_->access_flags_ &
~kAccInterface) | kAccFinal) & kAccJavaFlagsMask;
if (InsertClass(new_class)) {
return new_class;
}
// Another thread must have loaded the class after we
// started but before we finished. Abandon what we've
// done.
//
// (Yes, this happens.)
// Grab the winning class.
Class* other_class = LookupClass(descriptor, component_type_->class_loader_);
DCHECK(other_class != NULL);
return other_class;
}
Class* ClassLinker::FindPrimitiveClass(char type) {
switch (type) {
case 'B':
DCHECK(class_roots_->Get(kPrimitiveByte) != NULL);
return class_roots_->Get(kPrimitiveByte);
case 'C':
DCHECK(class_roots_->Get(kPrimitiveChar) != NULL);
return class_roots_->Get(kPrimitiveChar);
case 'D':
DCHECK(class_roots_->Get(kPrimitiveDouble) != NULL);
return class_roots_->Get(kPrimitiveDouble);
case 'F':
DCHECK(class_roots_->Get(kPrimitiveFloat) != NULL);
return class_roots_->Get(kPrimitiveFloat);
case 'I':
DCHECK(class_roots_->Get(kPrimitiveInt) != NULL);
return class_roots_->Get(kPrimitiveInt);
case 'J':
DCHECK(class_roots_->Get(kPrimitiveLong) != NULL);
return class_roots_->Get(kPrimitiveLong);
case 'S':
DCHECK(class_roots_->Get(kPrimitiveShort) != NULL);
return class_roots_->Get(kPrimitiveShort);
case 'Z':
DCHECK(class_roots_->Get(kPrimitiveBoolean) != NULL);
return class_roots_->Get(kPrimitiveBoolean);
case 'V':
DCHECK(class_roots_->Get(kPrimitiveVoid) != NULL);
return class_roots_->Get(kPrimitiveVoid);
case 'L':
case '[':
LOG(ERROR) << "Not a primitive type " << static_cast<int>(type);
default:
LOG(ERROR) << "Unknown primitive type " << static_cast<int>(type);
};
return NULL; // Not reachable.
}
bool ClassLinker::InsertClass(Class* klass) {
// TODO: acquire classes_lock_
const StringPiece& key = klass->GetDescriptor();
bool success = classes_.insert(std::make_pair(key, klass)).second;
// TODO: release classes_lock_
return success;
}
Class* ClassLinker::LookupClass(const StringPiece& descriptor, Object* class_loader) {
// TODO: acquire classes_lock_
Table::iterator it = classes_.find(descriptor);
// TODO: release classes_lock_
if (it == classes_.end()) {
return NULL;
} else {
return (*it).second;
}
}
bool ClassLinker::InitializeClass(Class* klass) {
CHECK(klass->GetStatus() == Class::kStatusResolved ||
klass->GetStatus() == Class::kStatusError);
Thread* self = Thread::Current();
{
ObjectLock lock(klass);
if (klass->GetStatus() < Class::kStatusVerified) {
if (klass->IsErroneous()) {
LG << "re-initializing failed class"; // TODO: throw
return false;
}
CHECK(klass->GetStatus() == Class::kStatusResolved);
klass->status_ = Class::kStatusVerifying;
if (!DexVerify::VerifyClass(klass)) {
LG << "Verification failed"; // TODO: ThrowVerifyError
Object* exception = self->GetException();
size_t field_offset = OFFSETOF_MEMBER(Class, verify_error_class_);
klass->SetFieldObject(field_offset, exception->GetClass());
klass->SetStatus(Class::kStatusError);
return false;
}
klass->SetStatus(Class::kStatusVerified);
}
if (klass->status_ == Class::kStatusInitialized) {
return true;
}
while (klass->status_ == Class::kStatusInitializing) {
// we caught somebody else in the act; was it us?
if (klass->clinit_thread_id_ == self->GetId()) {
LG << "recursive <clinit>";
return true;
}
CHECK(!self->IsExceptionPending());
lock.Wait(); // TODO: check for interruption
// When we wake up, repeat the test for init-in-progress. If
// there's an exception pending (only possible if
// "interruptShouldThrow" was set), bail out.
if (self->IsExceptionPending()) {
CHECK(false);
LG << "Exception in initialization."; // TODO: ExceptionInInitializerError
klass->SetStatus(Class::kStatusError);
return false;
}
if (klass->GetStatus() == Class::kStatusInitializing) {
continue;
}
DCHECK(klass->GetStatus() == Class::kStatusInitialized ||
klass->GetStatus() == Class::kStatusError);
if (klass->IsErroneous()) {
// The caller wants an exception, but it was thrown in a
// different thread. Synthesize one here.
LG << "<clinit> failed"; // TODO: throw UnsatisfiedLinkError
return false;
}
return true; // otherwise, initialized
}
// see if we failed previously
if (klass->IsErroneous()) {
// might be wise to unlock before throwing; depends on which class
// it is that we have locked
// TODO: throwEarlierClassFailure(klass);
return false;
}
if (!ValidateSuperClassDescriptors(klass)) {
klass->SetStatus(Class::kStatusError);
return false;
}
DCHECK(klass->status_ < Class::kStatusInitializing);
klass->clinit_thread_id_ = self->GetId();
klass->status_ = Class::kStatusInitializing;
}
if (!InitializeSuperClass(klass)) {
return false;
}
InitializeStaticFields(klass);
Method* clinit = klass->FindDirectMethodLocally("<clinit>", "()V");
if (clinit != NULL) {
} else {
// JValue unused;
// TODO: dvmCallMethod(self, method, NULL, &unused);
//CHECK(!"unimplemented");
}
{
ObjectLock lock(klass);
if (self->IsExceptionPending()) {
klass->SetStatus(Class::kStatusError);
} else {
klass->SetStatus(Class::kStatusInitialized);
}
lock.NotifyAll();
}
return true;
}
bool ClassLinker::ValidateSuperClassDescriptors(const Class* klass) {
if (klass->IsInterface()) {
return true;
}
// begin with the methods local to the superclass
if (klass->HasSuperClass() &&
klass->GetClassLoader() != klass->GetSuperClass()->GetClassLoader()) {
const Class* super = klass->GetSuperClass();
for (int i = super->NumVirtualMethods() - 1; i >= 0; --i) {
const Method* method = klass->GetVirtualMethod(i);
if (method != super->GetVirtualMethod(i) &&
!HasSameMethodDescriptorClasses(method, super, klass)) {
LG << "Classes resolve differently in superclass";
return false;
}
}
}
for (size_t i = 0; i < klass->iftable_count_; ++i) {
const InterfaceEntry* iftable = &klass->iftable_[i];
Class* interface = iftable->GetClass();
if (klass->GetClassLoader() != interface->GetClassLoader()) {
for (size_t j = 0; j < interface->NumVirtualMethods(); ++j) {
uint32_t vtable_index = iftable->method_index_array_[j];
const Method* method = klass->GetVirtualMethod(vtable_index);
if (!HasSameMethodDescriptorClasses(method, interface,
method->GetClass())) {
LG << "Classes resolve differently in interface"; // TODO: LinkageError
return false;
}
}
}
}
return true;
}
bool ClassLinker::HasSameMethodDescriptorClasses(const Method* method,
const Class* klass1,
const Class* klass2) {
const DexFile* dex_file = FindDexFile(method->GetClass()->GetDexCache());
const DexFile::ProtoId& proto_id = dex_file->GetProtoId(method->proto_idx_);
DexFile::ParameterIterator *it;
for (it = dex_file->GetParameterIterator(proto_id); it->HasNext(); it->Next()) {
const char* descriptor = it->GetDescriptor();
if (descriptor == NULL) {
break;
}
if (descriptor[0] == 'L' || descriptor[0] == '[') {
// Found a non-primitive type.
if (!HasSameDescriptorClasses(descriptor, klass1, klass2)) {
return false;
}
}
}
// Check the return type
const char* descriptor = dex_file->GetReturnTypeDescriptor(proto_id);
if (descriptor[0] == 'L' || descriptor[0] == '[') {
if (HasSameDescriptorClasses(descriptor, klass1, klass2)) {
return false;
}
}
return true;
}
// Returns true if classes referenced by the descriptor are the
// same classes in klass1 as they are in klass2.
bool ClassLinker::HasSameDescriptorClasses(const char* descriptor,
const Class* klass1,
const Class* klass2) {
CHECK(descriptor != NULL);
CHECK(klass1 != NULL);
CHECK(klass2 != NULL);
#if 0
Class* found1 = FindClass(descriptor, klass1->GetClassLoader());
// TODO: found1 == NULL
Class* found2 = FindClass(descriptor, klass2->GetClassLoader());
// TODO: found2 == NULL
// TODO: lookup found1 in initiating loader list
if (found1 == NULL || found2 == NULL) {
Thread::Current()->ClearException();
if (found1 == found2) {
return true;
} else {
return false;
}
}
#endif
return true;
}
bool ClassLinker::HasSameArgumentTypes(const Method* m1, const Method* m2) const {
const DexFile* dex1 = FindDexFile(m1->GetClass()->GetDexCache());
const DexFile* dex2 = FindDexFile(m2->GetClass()->GetDexCache());
const DexFile::ProtoId& proto1 = dex1->GetProtoId(m1->proto_idx_);
const DexFile::ProtoId& proto2 = dex2->GetProtoId(m2->proto_idx_);
// TODO: compare ProtoId objects for equality and exit early
const DexFile::TypeList* type_list1 = dex1->GetProtoParameters(proto1);
const DexFile::TypeList* type_list2 = dex2->GetProtoParameters(proto2);
size_t arity1 = (type_list1 == NULL) ? 0 : type_list1->Size();
size_t arity2 = (type_list2 == NULL) ? 0 : type_list2->Size();
if (arity1 != arity2) {
return false;
}
for (size_t i = 0; i < arity1; ++i) {
uint32_t type_idx1 = type_list1->GetTypeItem(i).type_idx_;
uint32_t type_idx2 = type_list2->GetTypeItem(i).type_idx_;
const char* type1 = dex1->dexStringByTypeIdx(type_idx1);
const char* type2 = dex2->dexStringByTypeIdx(type_idx2);
if (strcmp(type1, type2) != 0) {
return false;
}
}
return true;
}
bool ClassLinker::HasSameReturnType(const Method* m1, const Method* m2) const {
const DexFile* dex1 = FindDexFile(m1->GetClass()->GetDexCache());
const DexFile* dex2 = FindDexFile(m2->GetClass()->GetDexCache());
const DexFile::ProtoId& proto1 = dex1->GetProtoId(m1->proto_idx_);
const DexFile::ProtoId& proto2 = dex2->GetProtoId(m2->proto_idx_);
const char* type1 = dex1->dexStringByTypeIdx(proto1.return_type_idx_);
const char* type2 = dex2->dexStringByTypeIdx(proto2.return_type_idx_);
return (strcmp(type1, type2) == 0);
}
bool ClassLinker::InitializeSuperClass(Class* klass) {
CHECK(klass != NULL);
// TODO: assert klass lock is acquired
if (!klass->IsInterface() && klass->HasSuperClass()) {
Class* super_class = klass->GetSuperClass();
if (super_class->GetStatus() != Class::kStatusInitialized) {
CHECK(!super_class->IsInterface());
klass->MonitorExit();
bool super_initialized = InitializeClass(super_class);
klass->MonitorEnter();
// TODO: check for a pending exception
if (!super_initialized) {
klass->SetStatus(Class::kStatusError);
klass->NotifyAll();
return false;
}
}
}
return true;
}
void ClassLinker::InitializeStaticFields(Class* klass) {
size_t num_static_fields = klass->NumStaticFields();
if (num_static_fields == 0) {
return;
}
DexCache* dex_cache = klass->GetDexCache();
if (dex_cache == NULL) {
return;
}
const StringPiece& descriptor = klass->GetDescriptor();
const DexFile* dex_file = FindDexFile(dex_cache);
const DexFile::ClassDef* dex_class_def = dex_file->FindClassDef(descriptor);
CHECK(dex_class_def != NULL);
const byte* addr = dex_file->GetEncodedArray(*dex_class_def);
size_t array_size = DecodeUnsignedLeb128(&addr);
for (size_t i = 0; i < array_size; ++i) {
StaticField* field = klass->GetStaticField(i);
JValue value;
DexFile::ValueType type = dex_file->ReadEncodedValue(&addr, &value);
switch (type) {
case DexFile::kByte:
field->SetByte(value.b);
break;
case DexFile::kShort:
field->SetShort(value.s);
break;
case DexFile::kChar:
field->SetChar(value.c);
break;
case DexFile::kInt:
field->SetInt(value.i);
break;
case DexFile::kLong:
field->SetLong(value.j);
break;
case DexFile::kFloat:
field->SetFloat(value.f);
break;
case DexFile::kDouble:
field->SetDouble(value.d);
break;
case DexFile::kString: {
uint32_t string_idx = value.i;
String* resolved = ResolveString(klass, string_idx);
field->SetObject(resolved);
break;
}
case DexFile::kBoolean:
field->SetBoolean(value.z);
break;
case DexFile::kNull:
field->SetObject(value.l);
break;
default:
LOG(FATAL) << "Unknown type " << static_cast<int>(type);
}
}
}
bool ClassLinker::LinkClass(Class* klass, const DexFile* dex_file) {
CHECK(klass->status_ == Class::kStatusIdx ||
klass->status_ == Class::kStatusLoaded);
if (klass->status_ == Class::kStatusIdx) {
if (!LinkInterfaces(klass, dex_file)) {
return false;
}
}
if (!LinkSuperClass(klass)) {
return false;
}
if (!LinkMethods(klass)) {
return false;
}
if (!LinkInstanceFields(klass)) {
return false;
}
CreateReferenceOffsets(klass);
CHECK_EQ(klass->status_, Class::kStatusLoaded);
klass->status_ = Class::kStatusResolved;
return true;
}
bool ClassLinker::LinkInterfaces(Class* klass, const DexFile* dex_file) {
// Mark the class as loaded.
klass->status_ = Class::kStatusLoaded;
if (klass->super_class_idx_ != DexFile::kDexNoIndex) {
Class* super_class = ResolveClass(klass, klass->super_class_idx_, dex_file);
if (super_class == NULL) {
LG << "Failed to resolve superclass";
return false;
}
klass->super_class_ = super_class; // TODO: write barrier
}
if (klass->NumInterfaces() > 0) {
for (size_t i = 0; i < klass->NumInterfaces(); ++i) {
uint32_t idx = klass->interfaces_idx_[i];
klass->SetInterface(i, ResolveClass(klass, idx, dex_file));
if (klass->GetInterface(i) == NULL) {
LG << "Failed to resolve interface";
return false;
}
// Verify
if (!klass->CanAccess(klass->GetInterface(i))) {
LG << "Inaccessible interface";
return false;
}
}
}
return true;
}
bool ClassLinker::LinkSuperClass(Class* klass) {
CHECK(!klass->IsPrimitive());
const Class* super = klass->GetSuperClass();
if (klass->GetDescriptor() == "Ljava/lang/Object;") {
if (super != NULL) {
LG << "Superclass must not be defined"; // TODO: ClassFormatError
return false;
}
// TODO: clear finalize attribute
return true;
}
if (super == NULL) {
LG << "No superclass defined"; // TODO: LinkageError
return false;
}
// Verify
if (super->IsFinal()) {
LG << "Superclass is declared final"; // TODO: IncompatibleClassChangeError
return false;
}
if (super->IsInterface()) {
LG << "Superclass is an interface"; // TODO: IncompatibleClassChangeError
return false;
}
if (!klass->CanAccess(super)) {
LG << "Superclass is inaccessible"; // TODO: IllegalAccessError
return false;
}
return true;
}
// Populate the class vtable and itable.
bool ClassLinker::LinkMethods(Class* klass) {
if (klass->IsInterface()) {
// No vtable.
size_t count = klass->NumVirtualMethods();
if (!IsUint(16, count)) {
LG << "Too many methods on interface"; // TODO: VirtualMachineError
return false;
}
for (size_t i = 0; i < count; ++i) {
klass->GetVirtualMethod(i)->method_index_ = i;
}
} else {
// Link virtual method tables
LinkVirtualMethods(klass);
// Link interface method tables
LinkInterfaceMethods(klass);
// Insert stubs.
LinkAbstractMethods(klass);
}
return true;
}
bool ClassLinker::LinkVirtualMethods(Class* klass) {
if (klass->HasSuperClass()) {
uint32_t max_count = klass->NumVirtualMethods() + klass->GetSuperClass()->vtable_->GetLength();
size_t actual_count = klass->GetSuperClass()->vtable_->GetLength();
CHECK_LE(actual_count, max_count);
// TODO: do not assign to the vtable field until it is fully constructed.
klass->vtable_ = klass->GetSuperClass()->vtable_->CopyOf(max_count);
// See if any of our virtual methods override the superclass.
for (size_t i = 0; i < klass->NumVirtualMethods(); ++i) {
Method* local_method = klass->GetVirtualMethod(i);
size_t j = 0;
for (; j < actual_count; ++j) {
Method* super_method = klass->vtable_->Get(j);
if (HasSameNameAndPrototype(local_method, super_method)) {
// Verify
if (super_method->IsFinal()) {
LG << "Method overrides final method"; // TODO: VirtualMachineError
return false;
}
klass->vtable_->Set(j, local_method);
local_method->method_index_ = j;
break;
}
}
if (j == actual_count) {
// Not overriding, append.
klass->vtable_->Set(actual_count, local_method);
local_method->method_index_ = actual_count;
actual_count += 1;
}
}
if (!IsUint(16, actual_count)) {
LG << "Too many methods defined on class"; // TODO: VirtualMachineError
return false;
}
CHECK_LE(actual_count, max_count);
if (actual_count < max_count) {
// TODO: do not assign to the vtable field until it is fully constructed.
klass->vtable_ = klass->vtable_->CopyOf(actual_count);
}
} else {
CHECK(klass->GetDescriptor() == "Ljava/lang/Object;");
uint32_t num_virtual_methods = klass->NumVirtualMethods();
CHECK(klass->GetDescriptor() == "Ljava/lang/Object;");
if (!IsUint(16, num_virtual_methods)) {
LG << "Too many methods"; // TODO: VirtualMachineError
return false;
}
// TODO: do not assign to the vtable field until it is fully constructed.
klass->vtable_ = AllocObjectArray<Method>(num_virtual_methods);
for (size_t i = 0; i < num_virtual_methods; ++i) {
klass->vtable_->Set(i, klass->GetVirtualMethod(i));
klass->GetVirtualMethod(i)->method_index_ = i & 0xFFFF;
}
}
return true;
}
bool ClassLinker::LinkInterfaceMethods(Class* klass) {
int pool_offset = 0;
int pool_size = 0;
int miranda_count = 0;
int miranda_alloc = 0;
size_t super_ifcount;
if (klass->HasSuperClass()) {
super_ifcount = klass->GetSuperClass()->iftable_count_;
} else {
super_ifcount = 0;
}
size_t ifcount = super_ifcount;
ifcount += klass->NumInterfaces();
for (size_t i = 0; i < klass->NumInterfaces(); i++) {
ifcount += klass->GetInterface(i)->iftable_count_;
}
if (ifcount == 0) {
DCHECK(klass->iftable_count_ == 0);
DCHECK(klass->iftable_ == NULL);
return true;
}
klass->iftable_ = new InterfaceEntry[ifcount * sizeof(InterfaceEntry)];
memset(klass->iftable_, 0x00, sizeof(InterfaceEntry) * ifcount);
if (super_ifcount != 0) {
memcpy(klass->iftable_, klass->GetSuperClass()->iftable_,
sizeof(InterfaceEntry) * super_ifcount);
}
// Flatten the interface inheritance hierarchy.
size_t idx = super_ifcount;
for (size_t i = 0; i < klass->NumInterfaces(); i++) {
Class* interf = klass->GetInterface(i);
DCHECK(interf != NULL);
if (!interf->IsInterface()) {
LG << "Class implements non-interface class"; // TODO: IncompatibleClassChangeError
return false;
}
klass->iftable_[idx++].SetClass(interf);
for (size_t j = 0; j < interf->iftable_count_; j++) {
klass->iftable_[idx++].SetClass(interf->iftable_[j].GetClass());
}
}
CHECK_EQ(idx, ifcount);
klass->iftable_count_ = ifcount;
if (klass->IsInterface() || super_ifcount == ifcount) {
return true;
}
for (size_t i = super_ifcount; i < ifcount; i++) {
pool_size += klass->iftable_[i].GetClass()->NumVirtualMethods();
}
if (pool_size == 0) {
return true;
}
klass->ifvi_pool_count_ = pool_size;
klass->ifvi_pool_ = new uint32_t[pool_size];
std::vector<Method*> miranda_list;
for (size_t i = super_ifcount; i < ifcount; ++i) {
klass->iftable_[i].method_index_array_ = klass->ifvi_pool_ + pool_offset;
Class* interface = klass->iftable_[i].GetClass();
pool_offset += interface->NumVirtualMethods(); // end here
for (size_t j = 0; j < interface->NumVirtualMethods(); ++j) {
Method* interface_method = interface->GetVirtualMethod(j);
int k; // must be signed
for (k = klass->vtable_->GetLength() - 1; k >= 0; --k) {
if (HasSameNameAndPrototype(interface_method, klass->vtable_->Get(k))) {
if (!klass->vtable_->Get(k)->IsPublic()) {
LG << "Implementation not public";
return false;
}
klass->iftable_[i].method_index_array_[j] = k;
break;
}
}
if (k < 0) {
if (miranda_count == miranda_alloc) {
miranda_alloc += 8;
if (miranda_list.empty()) {
miranda_list.resize(miranda_alloc);
} else {
miranda_list.resize(miranda_alloc);
}
}
int mir;
for (mir = 0; mir < miranda_count; mir++) {
if (HasSameNameAndPrototype(miranda_list[mir], interface_method)) {
break;
}
}
// point the interface table at a phantom slot index
klass->iftable_[i].method_index_array_[j] = klass->vtable_->GetLength() + mir;
if (mir == miranda_count) {
miranda_list[miranda_count++] = interface_method;
}
}
}
}
if (miranda_count != 0) {
int old_method_count = klass->NumVirtualMethods();
int new_method_count = old_method_count + miranda_count;
klass->virtual_methods_ = klass->virtual_methods_->CopyOf(new_method_count);
CHECK(klass->vtable_ != NULL);
int old_vtable_count = klass->vtable_->GetLength();
int new_vtable_count = old_vtable_count + miranda_count;
// TODO: do not assign to the vtable field until it is fully constructed.
klass->vtable_ = klass->vtable_->CopyOf(new_vtable_count);
for (int i = 0; i < miranda_count; i++) {
Method* meth = AllocMethod();
memcpy(meth, miranda_list[i], sizeof(Method));
meth->klass_ = klass;
meth->access_flags_ |= kAccMiranda;
meth->method_index_ = 0xFFFF & (old_vtable_count + i);
klass->SetVirtualMethod(old_method_count + i, meth);
klass->vtable_->Set(old_vtable_count + i, meth);
}
}
return true;
}
void ClassLinker::LinkAbstractMethods(Class* klass) {
for (size_t i = 0; i < klass->NumVirtualMethods(); ++i) {
Method* method = klass->GetVirtualMethod(i);
if (method->IsAbstract()) {
method->insns_ = reinterpret_cast<uint16_t*>(0xFFFFFFFF); // TODO: AbstractMethodError
}
}
}
bool ClassLinker::LinkInstanceFields(Class* klass) {
int field_offset;
if (klass->GetSuperClass() != NULL) {
field_offset = klass->GetSuperClass()->object_size_;
} else {
field_offset = OFFSETOF_MEMBER(DataObject, fields_);
}
// Move references to the front.
klass->num_reference_instance_fields_ = 0;
size_t i = 0;
for ( ; i < klass->NumInstanceFields(); i++) {
InstanceField* pField = klass->GetInstanceField(i);
char c = pField->GetType();
if (c != '[' && c != 'L') {
for (size_t j = klass->NumInstanceFields() - 1; j > i; j--) {
InstanceField* refField = klass->GetInstanceField(j);
char rc = refField->GetType();
if (rc == '[' || rc == 'L') {
klass->SetInstanceField(i, refField);
klass->SetInstanceField(j, pField);
pField = refField;
c = rc;
klass->num_reference_instance_fields_++;
break;
}
}
} else {
klass->num_reference_instance_fields_++;
}
if (c != '[' && c != 'L') {
break;
}
pField->SetOffset(field_offset);
field_offset += sizeof(uint32_t);
}
// Now we want to pack all of the double-wide fields together. If
// we're not aligned, though, we want to shuffle one 32-bit field
// into place. If we can't find one, we'll have to pad it.
if (i != klass->NumInstanceFields() && (field_offset & 0x04) != 0) {
InstanceField* pField = klass->GetInstanceField(i);
char c = pField->GetType();
if (c != 'J' && c != 'D') {
// The field that comes next is 32-bit, so just advance past it.
DCHECK(c != '[');
DCHECK(c != 'L');
pField->SetOffset(field_offset);
field_offset += sizeof(uint32_t);
i++;
} else {
// Next field is 64-bit, so search for a 32-bit field we can
// swap into it.
bool found = false;
for (size_t j = klass->NumInstanceFields() - 1; j > i; j--) {
InstanceField* singleField = klass->GetInstanceField(j);
char rc = singleField->GetType();
if (rc != 'J' && rc != 'D') {
klass->SetInstanceField(i, singleField);
klass->SetInstanceField(j, pField);
pField = singleField;
pField->SetOffset(field_offset);
field_offset += sizeof(uint32_t);
found = true;
i++;
break;
}
}
if (!found) {
field_offset += sizeof(uint32_t);
}
}
}
// Alignment is good, shuffle any double-wide fields forward, and
// finish assigning field offsets to all fields.
DCHECK(i == klass->NumInstanceFields() || (field_offset & 0x04) == 0);
for ( ; i < klass->NumInstanceFields(); i++) {
InstanceField* pField = klass->GetInstanceField(i);
char c = pField->GetType();
if (c != 'D' && c != 'J') {
for (size_t j = klass->NumInstanceFields() - 1; j > i; j--) {
InstanceField* doubleField = klass->GetInstanceField(j);
char rc = doubleField->GetType();
if (rc == 'D' || rc == 'J') {
klass->SetInstanceField(i, doubleField);
klass->SetInstanceField(j, pField);
pField = doubleField;
c = rc;
break;
}
}
} else {
// This is a double-wide field, leave it be.
}
pField->SetOffset(field_offset);
field_offset += sizeof(uint32_t);
if (c == 'J' || c == 'D')
field_offset += sizeof(uint32_t);
}
#ifndef NDEBUG
// Make sure that all reference fields appear before
// non-reference fields, and all double-wide fields are aligned.
bool seen_non_ref = false;
for (i = 0; i < klass->NumInstanceFields(); i++) {
InstanceField *pField = klass->GetInstanceField(i);
char c = pField->GetType();
if (c == 'D' || c == 'J') {
DCHECK_EQ(0U, pField->GetOffset() & 0x07);
}
if (c != '[' && c != 'L') {
if (!seen_non_ref) {
seen_non_ref = true;
DCHECK_EQ(klass->NumReferenceInstanceFields(), i);
}
} else {
DCHECK(!seen_non_ref);
}
}
if (!seen_non_ref) {
DCHECK_EQ(klass->NumInstanceFields(), klass->NumReferenceInstanceFields());
}
#endif
klass->object_size_ = field_offset;
return true;
}
// Set the bitmap of reference offsets, refOffsets, from the ifields
// list.
void ClassLinker::CreateReferenceOffsets(Class* klass) {
uint32_t reference_offsets = 0;
if (klass->HasSuperClass()) {
reference_offsets = klass->GetSuperClass()->GetReferenceOffsets();
}
// If our superclass overflowed, we don't stand a chance.
if (reference_offsets != CLASS_WALK_SUPER) {
// All of the fields that contain object references are guaranteed
// to be at the beginning of the ifields list.
for (size_t i = 0; i < klass->NumReferenceInstanceFields(); ++i) {
// Note that, per the comment on struct InstField, f->byteOffset
// is the offset from the beginning of obj, not the offset into
// obj->instanceData.
const InstanceField* field = klass->GetInstanceField(i);
size_t byte_offset = field->GetOffset();
CHECK_GE(byte_offset, CLASS_SMALLEST_OFFSET);
CHECK_EQ(byte_offset & (CLASS_OFFSET_ALIGNMENT - 1), 0U);
if (CLASS_CAN_ENCODE_OFFSET(byte_offset)) {
uint32_t new_bit = CLASS_BIT_FROM_OFFSET(byte_offset);
CHECK_NE(new_bit, 0U);
reference_offsets |= new_bit;
} else {
reference_offsets = CLASS_WALK_SUPER;
break;
}
}
}
klass->SetReferenceOffsets(reference_offsets);
}
Class* ClassLinker::ResolveClass(const Class* referrer,
uint32_t class_idx,
const DexFile* dex_file) {
DexCache* dex_cache = referrer->GetDexCache();
Class* resolved = dex_cache->GetResolvedClass(class_idx);
if (resolved != NULL) {
return resolved;
}
const char* descriptor = dex_file->dexStringByTypeIdx(class_idx);
if (descriptor[0] != '\0' && descriptor[1] == '\0') {
resolved = FindPrimitiveClass(descriptor[0]);
} else {
resolved = FindClass(descriptor, referrer->GetClassLoader(), dex_file);
}
if (resolved != NULL) {
Class* check = resolved->IsArray() ? resolved->component_type_ : resolved;
if (referrer->GetDexCache() != check->GetDexCache()) {
if (check->GetClassLoader() != NULL) {
LG << "Class resolved by unexpected DEX"; // TODO: IllegalAccessError
return NULL;
}
}
dex_cache->SetResolvedClass(class_idx, resolved);
} else {
DCHECK(Thread::Current()->IsExceptionPending());
}
return resolved;
}
Method* ResolveMethod(const Class* referrer, uint32_t method_idx,
/*MethodType*/ int method_type) {
CHECK(false);
return NULL;
}
String* ClassLinker::ResolveString(const Class* referring,
uint32_t string_idx) {
const DexFile* dex_file = FindDexFile(referring->GetDexCache());
const DexFile::StringId& string_id = dex_file->GetStringId(string_idx);
int32_t utf16_length = dex_file->GetStringLength(string_id);
const char* utf8_data = dex_file->GetStringData(string_id);
String* new_string = AllocStringFromModifiedUtf8(utf16_length, utf8_data);
// TODO: intern the new string
referring->GetDexCache()->SetResolvedString(string_idx, new_string);
return new_string;
}
} // namespace art