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android/platform/art/bc50ac127d/./runtime/runtime_image.cc
blob: a0598bbcd1ac584772a9b75ff75a2788f7cc5f5e [file]
/*
* Copyright (C) 2022 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 "runtime_image.h"
#include <lz4.h>
#include <sstream>
#include <unistd.h>
#include "android-base/file.h"
#include "android-base/stringprintf.h"
#include "android-base/strings.h"
#include "base/arena_allocator.h"
#include "base/arena_containers.h"
#include "base/bit_utils.h"
#include "base/file_utils.h"
#include "base/length_prefixed_array.h"
#include "base/scoped_flock.h"
#include "base/stl_util.h"
#include "base/systrace.h"
#include "base/unix_file/fd_file.h"
#include "base/utils.h"
#include "class_loader_context.h"
#include "class_loader_utils.h"
#include "class_root-inl.h"
#include "gc/space/image_space.h"
#include "image.h"
#include "mirror/object-inl.h"
#include "mirror/object-refvisitor-inl.h"
#include "mirror/object_array-alloc-inl.h"
#include "mirror/object_array-inl.h"
#include "mirror/object_array.h"
#include "mirror/string-inl.h"
#include "oat.h"
#include "profile/profile_compilation_info.h"
#include "scoped_thread_state_change-inl.h"
#include "vdex_file.h"
namespace art {
using android::base::StringPrintf;
/**
* The native data structures that we store in the image.
*/
enum class NativeRelocationKind {
kArtFieldArray,
kArtMethodArray,
kArtMethod,
kImTable,
// For dex cache arrays which can stay in memory even after startup. Those are
// dex cache arrays whose size is below a given threshold, defined by
// DexCache::ShouldAllocateFullArray.
kFullNativeDexCacheArray,
// For dex cache arrays which we will want to release after app startup.
kStartupNativeDexCacheArray,
};
/**
* Helper class to generate an app image at runtime.
*/
class RuntimeImageHelper {
public:
explicit RuntimeImageHelper(gc::Heap* heap) :
sections_(ImageHeader::kSectionCount),
boot_image_begin_(heap->GetBootImagesStartAddress()),
boot_image_size_(heap->GetBootImagesSize()),
image_begin_(boot_image_begin_ + boot_image_size_),
// Note: image relocation considers the image header in the bitmap.
object_section_size_(sizeof(ImageHeader)),
intern_table_(InternStringHash(this), InternStringEquals(this)),
class_table_(ClassDescriptorHash(this), ClassDescriptorEquals()) {}
bool Generate(std::string* error_msg) {
if (!WriteObjects(error_msg)) {
return false;
}
// Generate the sections information stored in the header.
CreateImageSections();
// Now that all sections have been created and we know their offset and
// size, relocate native pointers inside classes and ImTables.
RelocateNativePointers();
// Generate the bitmap section, stored page aligned after the sections data
// and of size `object_section_size_` page aligned.
size_t sections_end = sections_[ImageHeader::kSectionMetadata].End();
image_bitmap_ = gc::accounting::ContinuousSpaceBitmap::Create(
"image bitmap",
reinterpret_cast<uint8_t*>(image_begin_),
RoundUp(object_section_size_, kPageSize));
for (uint32_t offset : object_offsets_) {
DCHECK(IsAligned<kObjectAlignment>(image_begin_ + sizeof(ImageHeader) + offset));
image_bitmap_.Set(
reinterpret_cast<mirror::Object*>(image_begin_ + sizeof(ImageHeader) + offset));
}
const size_t bitmap_bytes = image_bitmap_.Size();
auto* bitmap_section = &sections_[ImageHeader::kSectionImageBitmap];
*bitmap_section = ImageSection(RoundUp(sections_end, kPageSize),
RoundUp(bitmap_bytes, kPageSize));
// Compute boot image checksum and boot image components, to be stored in
// the header.
gc::Heap* const heap = Runtime::Current()->GetHeap();
uint32_t boot_image_components = 0u;
uint32_t boot_image_checksums = 0u;
const std::vector<gc::space::ImageSpace*>& image_spaces = heap->GetBootImageSpaces();
for (size_t i = 0u, size = image_spaces.size(); i != size; ) {
const ImageHeader& header = image_spaces[i]->GetImageHeader();
boot_image_components += header.GetComponentCount();
boot_image_checksums ^= header.GetImageChecksum();
DCHECK_LE(header.GetImageSpaceCount(), size - i);
i += header.GetImageSpaceCount();
}
header_ = ImageHeader(
/* image_reservation_size= */ RoundUp(sections_end, kPageSize),
/* component_count= */ 1,
image_begin_,
sections_end,
sections_.data(),
/* image_roots= */ image_begin_ + sizeof(ImageHeader),
/* oat_checksum= */ 0,
/* oat_file_begin= */ 0,
/* oat_data_begin= */ 0,
/* oat_data_end= */ 0,
/* oat_file_end= */ 0,
heap->GetBootImagesStartAddress(),
heap->GetBootImagesSize(),
boot_image_components,
boot_image_checksums,
static_cast<uint32_t>(kRuntimePointerSize));
// Data size includes everything except the bitmap and the header.
header_.data_size_ = sections_end - sizeof(ImageHeader);
// Write image methods - needs to happen after creation of the header.
WriteImageMethods();
return true;
}
const std::vector<uint8_t>& GetObjects() const {
return objects_;
}
const std::vector<uint8_t>& GetArtMethods() const {
return art_methods_;
}
const std::vector<uint8_t>& GetArtFields() const {
return art_fields_;
}
const std::vector<uint8_t>& GetImTables() const {
return im_tables_;
}
const std::vector<uint8_t>& GetMetadata() const {
return metadata_;
}
const std::vector<uint8_t>& GetDexCacheArrays() const {
return dex_cache_arrays_;
}
const std::vector<AppImageReferenceOffsetInfo>& GetStringReferenceOffsets() const {
return string_reference_offsets_;
}
const ImageHeader& GetHeader() const {
return header_;
}
const gc::accounting::ContinuousSpaceBitmap& GetImageBitmap() const {
return image_bitmap_;
}
const std::string& GetDexLocation() const {
return dex_location_;
}
void GenerateInternData(std::vector<uint8_t>& data) const {
intern_table_.WriteToMemory(data.data());
}
void GenerateClassTableData(std::vector<uint8_t>& data) const {
class_table_.WriteToMemory(data.data());
}
private:
bool IsInBootImage(const void* obj) const {
return reinterpret_cast<uintptr_t>(obj) - boot_image_begin_ < boot_image_size_;
}
// Returns a pointer that can be stored in `objects_`:
// - The pointer itself for boot image objects,
// - The offset in the image for all other objects.
mirror::Object* GetOrComputeImageAddress(ObjPtr<mirror::Object> object)
REQUIRES_SHARED(Locks::mutator_lock_) {
if (object == nullptr || IsInBootImage(object.Ptr())) {
DCHECK(object == nullptr || Runtime::Current()->GetHeap()->ObjectIsInBootImageSpace(object));
return object.Ptr();
}
if (object->IsClassLoader()) {
// DexCache and Class point to class loaders. For runtime-generated app
// images, we don't encode the class loader. It will be set when the
// runtime is loading the image.
return nullptr;
}
if (object->GetClass() == GetClassRoot<mirror::ClassExt>()) {
// No need to encode `ClassExt`. If needed, it will be reconstructed at
// runtime.
return nullptr;
}
uint32_t offset = 0u;
if (object->IsClass()) {
offset = CopyClass(object->AsClass());
} else if (object->IsDexCache()) {
offset = CopyDexCache(object->AsDexCache());
} else {
offset = CopyObject(object);
}
return reinterpret_cast<mirror::Object*>(image_begin_ + sizeof(ImageHeader) + offset);
}
void CreateImageSections() {
sections_[ImageHeader::kSectionObjects] = ImageSection(0u, object_section_size_);
sections_[ImageHeader::kSectionArtFields] =
ImageSection(sections_[ImageHeader::kSectionObjects].End(), art_fields_.size());
// Round up to the alignment for ArtMethod.
static_assert(IsAligned<sizeof(void*)>(ArtMethod::Size(kRuntimePointerSize)));
size_t cur_pos = RoundUp(sections_[ImageHeader::kSectionArtFields].End(), sizeof(void*));
sections_[ImageHeader::kSectionArtMethods] = ImageSection(cur_pos, art_methods_.size());
// Round up to the alignment for ImTables.
cur_pos = RoundUp(sections_[ImageHeader::kSectionArtMethods].End(), sizeof(void*));
sections_[ImageHeader::kSectionImTables] = ImageSection(cur_pos, im_tables_.size());
// Round up to the alignment for conflict tables.
cur_pos = RoundUp(sections_[ImageHeader::kSectionImTables].End(), sizeof(void*));
sections_[ImageHeader::kSectionIMTConflictTables] = ImageSection(cur_pos, 0u);
sections_[ImageHeader::kSectionRuntimeMethods] =
ImageSection(sections_[ImageHeader::kSectionIMTConflictTables].End(), 0u);
// Round up to the alignment the string table expects. See HashSet::WriteToMemory.
cur_pos = RoundUp(sections_[ImageHeader::kSectionRuntimeMethods].End(), sizeof(uint64_t));
size_t intern_table_bytes = intern_table_.WriteToMemory(nullptr);
sections_[ImageHeader::kSectionInternedStrings] = ImageSection(cur_pos, intern_table_bytes);
// Obtain the new position and round it up to the appropriate alignment.
cur_pos = RoundUp(sections_[ImageHeader::kSectionInternedStrings].End(), sizeof(uint64_t));
size_t class_table_bytes = class_table_.WriteToMemory(nullptr);
sections_[ImageHeader::kSectionClassTable] = ImageSection(cur_pos, class_table_bytes);
// Round up to the alignment of the offsets we are going to store.
cur_pos = RoundUp(sections_[ImageHeader::kSectionClassTable].End(), sizeof(uint32_t));
sections_[ImageHeader::kSectionStringReferenceOffsets] = ImageSection(
cur_pos, string_reference_offsets_.size() * sizeof(string_reference_offsets_[0]));
// Round up to the alignment dex caches arrays expects.
cur_pos =
RoundUp(sections_[ImageHeader::kSectionStringReferenceOffsets].End(), sizeof(uint32_t));
sections_[ImageHeader::kSectionDexCacheArrays] =
ImageSection(cur_pos, dex_cache_arrays_.size());
// Round up to the alignment expected for the metadata.
cur_pos = RoundUp(sections_[ImageHeader::kSectionDexCacheArrays].End(), sizeof(uint32_t));
sections_[ImageHeader::kSectionMetadata] = ImageSection(cur_pos, metadata_.size());
}
// Returns the copied mirror Object if in the image, or the object directly if
// in the boot image. For the copy, this is really its content, it should not
// be returned as an `ObjPtr` (as it's not a GC object), nor stored anywhere.
template<typename T> T* FromImageOffsetToRuntimeContent(uint32_t offset) {
if (offset == 0u || IsInBootImage(reinterpret_cast<const void*>(offset))) {
return reinterpret_cast<T*>(offset);
}
uint32_t vector_data_offset = FromImageOffsetToVectorOffset(offset);
return reinterpret_cast<T*>(objects_.data() + vector_data_offset);
}
uint32_t FromImageOffsetToVectorOffset(uint32_t offset) const {
DCHECK(!IsInBootImage(reinterpret_cast<const void*>(offset)));
return offset - sizeof(ImageHeader) - image_begin_;
}
class InternStringHash {
public:
explicit InternStringHash(RuntimeImageHelper* helper) : helper_(helper) {}
// NO_THREAD_SAFETY_ANALYSIS as these helpers get passed to `HashSet`.
size_t operator()(mirror::String* str) const NO_THREAD_SAFETY_ANALYSIS {
int32_t hash = str->GetStoredHashCode();
DCHECK_EQ(hash, str->ComputeHashCode());
// An additional cast to prevent undesired sign extension.
return static_cast<uint32_t>(hash);
}
size_t operator()(uint32_t entry) const NO_THREAD_SAFETY_ANALYSIS {
return (*this)(helper_->FromImageOffsetToRuntimeContent<mirror::String>(entry));
}
private:
RuntimeImageHelper* helper_;
};
class InternStringEquals {
public:
explicit InternStringEquals(RuntimeImageHelper* helper) : helper_(helper) {}
// NO_THREAD_SAFETY_ANALYSIS as these helpers get passed to `HashSet`.
bool operator()(uint32_t entry, mirror::String* other) const NO_THREAD_SAFETY_ANALYSIS {
if (kIsDebugBuild) {
Locks::mutator_lock_->AssertSharedHeld(Thread::Current());
}
return other->Equals(helper_->FromImageOffsetToRuntimeContent<mirror::String>(entry));
}
bool operator()(uint32_t entry, uint32_t other) const NO_THREAD_SAFETY_ANALYSIS {
return (*this)(entry, helper_->FromImageOffsetToRuntimeContent<mirror::String>(other));
}
private:
RuntimeImageHelper* helper_;
};
using InternTableSet =
HashSet<uint32_t, DefaultEmptyFn<uint32_t>, InternStringHash, InternStringEquals>;
class ClassDescriptorHash {
public:
explicit ClassDescriptorHash(RuntimeImageHelper* helper) : helper_(helper) {}
uint32_t operator()(const ClassTable::TableSlot& slot) const NO_THREAD_SAFETY_ANALYSIS {
uint32_t ptr = slot.NonHashData();
if (helper_->IsInBootImage(reinterpret_cast32<const void*>(ptr))) {
return reinterpret_cast32<mirror::Class*>(ptr)->DescriptorHash();
}
return helper_->class_hashes_[helper_->FromImageOffsetToVectorOffset(ptr)];
}
private:
RuntimeImageHelper* helper_;
};
class ClassDescriptorEquals {
public:
ClassDescriptorEquals() {}
bool operator()(const ClassTable::TableSlot& a, const ClassTable::TableSlot& b)
const NO_THREAD_SAFETY_ANALYSIS {
// No need to fetch the descriptor: we know the classes we are inserting
// in the ClassTable are unique.
return a.Data() == b.Data();
}
};
using ClassTableSet = HashSet<ClassTable::TableSlot,
ClassTable::TableSlotEmptyFn,
ClassDescriptorHash,
ClassDescriptorEquals>;
// Helper class to collect classes that we will generate in the image.
class ClassTableVisitor {
public:
ClassTableVisitor(Handle<mirror::ClassLoader> loader, VariableSizedHandleScope& handles)
: loader_(loader), handles_(handles) {}
bool operator()(ObjPtr<mirror::Class> klass) REQUIRES_SHARED(Locks::mutator_lock_) {
// Record app classes and boot classpath classes: app classes will be
// generated in the image and put in the class table, boot classpath
// classes will be put in the class table.
ObjPtr<mirror::ClassLoader> class_loader = klass->GetClassLoader();
if (class_loader == loader_.Get() || class_loader == nullptr) {
handles_.NewHandle(klass);
}
return true;
}
private:
Handle<mirror::ClassLoader> loader_;
VariableSizedHandleScope& handles_;
};
// Helper class visitor to filter out classes we cannot emit.
class PruneVisitor {
public:
PruneVisitor(Thread* self,
RuntimeImageHelper* helper,
const ArenaSet<const DexFile*>& dex_files,
ArenaVector<Handle<mirror::Class>>& classes,
ArenaAllocator& allocator)
: self_(self),
helper_(helper),
dex_files_(dex_files),
visited_(allocator.Adapter()),
classes_to_write_(classes) {}
bool CanEmitHelper(Handle<mirror::Class> cls) REQUIRES_SHARED(Locks::mutator_lock_) {
// Only emit classes that are resolved and not erroneous.
if (!cls->IsResolved() || cls->IsErroneous()) {
return false;
}
// Classes in the boot image can be trivially encoded directly.
if (helper_->IsInBootImage(cls.Get())) {
return true;
}
// If the class comes from a dex file which is not part of the primary
// APK, don't encode it.
if (!ContainsElement(dex_files_, &cls->GetDexFile())) {
return false;
}
// Ensure pointers to classes in `cls` can also be emitted.
StackHandleScope<1> hs(self_);
MutableHandle<mirror::Class> other_class = hs.NewHandle(cls->GetSuperClass());
if (!CanEmit(other_class)) {
return false;
}
other_class.Assign(cls->GetComponentType());
if (!CanEmit(other_class)) {
return false;
}
for (size_t i = 0, num_interfaces = cls->NumDirectInterfaces(); i < num_interfaces; ++i) {
other_class.Assign(cls->GetDirectInterface(i));
if (!CanEmit(other_class)) {
return false;
}
}
return true;
}
bool CanEmit(Handle<mirror::Class> cls) REQUIRES_SHARED(Locks::mutator_lock_) {
if (cls == nullptr) {
return true;
}
const dex::ClassDef* class_def = cls->GetClassDef();
if (class_def == nullptr) {
// Covers array classes and proxy classes.
// TODO: Handle these differently.
return false;
}
auto existing = visited_.find(class_def);
if (existing != visited_.end()) {
// Already processed;
return existing->second == VisitState::kCanEmit;
}
visited_.Put(class_def, VisitState::kVisiting);
if (CanEmitHelper(cls)) {
visited_.Overwrite(class_def, VisitState::kCanEmit);
return true;
} else {
visited_.Overwrite(class_def, VisitState::kCannotEmit);
return false;
}
}
void Visit(Handle<mirror::Object> obj) REQUIRES_SHARED(Locks::mutator_lock_) {
MutableHandle<mirror::Class> cls(obj.GetReference());
if (CanEmit(cls)) {
if (cls->IsBootStrapClassLoaded()) {
DCHECK(helper_->IsInBootImage(cls.Get()));
// Insert the bootclasspath class in the class table.
uint32_t hash = cls->DescriptorHash();
helper_->class_table_.InsertWithHash(ClassTable::TableSlot(cls.Get(), hash), hash);
} else {
classes_to_write_.push_back(cls);
}
}
}
private:
enum class VisitState {
kVisiting,
kCanEmit,
kCannotEmit,
};
Thread* const self_;
RuntimeImageHelper* const helper_;
const ArenaSet<const DexFile*>& dex_files_;
ArenaSafeMap<const dex::ClassDef*, VisitState> visited_;
ArenaVector<Handle<mirror::Class>>& classes_to_write_;
};
void EmitClasses(Thread* self, Handle<mirror::ObjectArray<mirror::Object>> dex_cache_array)
REQUIRES_SHARED(Locks::mutator_lock_) {
ScopedTrace trace("Emit strings and classes");
ArenaAllocator allocator(Runtime::Current()->GetArenaPool());
ArenaSet<const DexFile*> dex_files(allocator.Adapter());
for (int32_t i = 0; i < dex_cache_array->GetLength(); ++i) {
dex_files.insert(dex_cache_array->Get(i)->AsDexCache()->GetDexFile());
}
StackHandleScope<1> hs(self);
Handle<mirror::ClassLoader> loader = hs.NewHandle(
dex_cache_array->Get(0)->AsDexCache()->GetClassLoader());
ClassTable* const class_table = loader->GetClassTable();
if (class_table == nullptr) {
return;
}
VariableSizedHandleScope handles(self);
{
ClassTableVisitor class_table_visitor(loader, handles);
class_table->Visit(class_table_visitor);
}
ArenaVector<Handle<mirror::Class>> classes_to_write(allocator.Adapter());
classes_to_write.reserve(class_table->Size());
{
PruneVisitor prune_visitor(self, this, dex_files, classes_to_write, allocator);
handles.VisitHandles(prune_visitor);
}
for (Handle<mirror::Class> cls : classes_to_write) {
ScopedAssertNoThreadSuspension sants("Writing class");
CopyClass(cls.Get());
}
}
// Helper visitor returning the location of a native pointer in the image.
class NativePointerVisitor {
public:
explicit NativePointerVisitor(RuntimeImageHelper* helper) : helper_(helper) {}
template <typename T>
T* operator()(T* ptr, void** dest_addr ATTRIBUTE_UNUSED) const {
return helper_->NativeLocationInImage(ptr, /* must_have_relocation= */ true);
}
template <typename T> T* operator()(T* ptr, bool must_have_relocation = true) const {
return helper_->NativeLocationInImage(ptr, must_have_relocation);
}
private:
RuntimeImageHelper* helper_;
};
template <typename T> T* NativeLocationInImage(T* ptr, bool must_have_relocation) const {
if (ptr == nullptr || IsInBootImage(ptr)) {
return ptr;
}
auto it = native_relocations_.find(ptr);
if (it == native_relocations_.end()) {
DCHECK(!must_have_relocation);
return nullptr;
}
switch (it->second.first) {
case NativeRelocationKind::kArtMethod:
case NativeRelocationKind::kArtMethodArray: {
uint32_t offset = sections_[ImageHeader::kSectionArtMethods].Offset();
return reinterpret_cast<T*>(image_begin_ + offset + it->second.second);
}
case NativeRelocationKind::kArtFieldArray: {
uint32_t offset = sections_[ImageHeader::kSectionArtFields].Offset();
return reinterpret_cast<T*>(image_begin_ + offset + it->second.second);
}
case NativeRelocationKind::kImTable: {
uint32_t offset = sections_[ImageHeader::kSectionImTables].Offset();
return reinterpret_cast<T*>(image_begin_ + offset + it->second.second);
}
case NativeRelocationKind::kStartupNativeDexCacheArray: {
uint32_t offset = sections_[ImageHeader::kSectionMetadata].Offset();
return reinterpret_cast<T*>(image_begin_ + offset + it->second.second);
}
case NativeRelocationKind::kFullNativeDexCacheArray: {
uint32_t offset = sections_[ImageHeader::kSectionDexCacheArrays].Offset();
return reinterpret_cast<T*>(image_begin_ + offset + it->second.second);
}
}
}
template <typename Visitor>
void RelocateMethodPointerArrays(mirror::Class* klass, const Visitor& visitor)
REQUIRES_SHARED(Locks::mutator_lock_) {
// A bit of magic here: we cast contents from our buffer to mirror::Class,
// and do pointer comparison between 1) these classes, and 2) boot image objects.
// Both kinds do not move.
// See if we need to fixup the vtable field.
mirror::Class* super = FromImageOffsetToRuntimeContent<mirror::Class>(
reinterpret_cast32<uint32_t>(
klass->GetSuperClass<kVerifyNone, kWithoutReadBarrier>().Ptr()));
DCHECK(super != nullptr) << "j.l.Object should never be in an app runtime image";
mirror::PointerArray* vtable = FromImageOffsetToRuntimeContent<mirror::PointerArray>(
reinterpret_cast32<uint32_t>(klass->GetVTable<kVerifyNone, kWithoutReadBarrier>().Ptr()));
mirror::PointerArray* super_vtable = FromImageOffsetToRuntimeContent<mirror::PointerArray>(
reinterpret_cast32<uint32_t>(super->GetVTable<kVerifyNone, kWithoutReadBarrier>().Ptr()));
if (vtable != nullptr && vtable != super_vtable) {
DCHECK(!IsInBootImage(vtable));
vtable->Fixup(vtable, kRuntimePointerSize, visitor);
}
// See if we need to fixup entries in the IfTable.
mirror::IfTable* iftable = FromImageOffsetToRuntimeContent<mirror::IfTable>(
reinterpret_cast32<uint32_t>(
klass->GetIfTable<kVerifyNone, kWithoutReadBarrier>().Ptr()));
mirror::IfTable* super_iftable = FromImageOffsetToRuntimeContent<mirror::IfTable>(
reinterpret_cast32<uint32_t>(
super->GetIfTable<kVerifyNone, kWithoutReadBarrier>().Ptr()));
int32_t iftable_count = iftable->Count();
int32_t super_iftable_count = super_iftable->Count();
for (int32_t i = 0; i < iftable_count; ++i) {
mirror::PointerArray* methods = FromImageOffsetToRuntimeContent<mirror::PointerArray>(
reinterpret_cast32<uint32_t>(
iftable->GetMethodArrayOrNull<kVerifyNone, kWithoutReadBarrier>(i).Ptr()));
mirror::PointerArray* super_methods = (i < super_iftable_count)
? FromImageOffsetToRuntimeContent<mirror::PointerArray>(
reinterpret_cast32<uint32_t>(
super_iftable->GetMethodArrayOrNull<kVerifyNone, kWithoutReadBarrier>(i).Ptr()))
: nullptr;
if (methods != super_methods) {
DCHECK(!IsInBootImage(methods));
methods->Fixup(methods, kRuntimePointerSize, visitor);
}
}
}
template <typename Visitor, typename T>
void RelocateNativeDexCacheArray(mirror::NativeArray<T>* old_method_array,
uint32_t num_ids,
const Visitor& visitor)
REQUIRES_SHARED(Locks::mutator_lock_) {
if (old_method_array == nullptr) {
return;
}
auto it = native_relocations_[old_method_array];
std::vector<uint8_t>& data = (it.first == NativeRelocationKind::kFullNativeDexCacheArray)
? dex_cache_arrays_ : metadata_;
mirror::NativeArray<T>* content_array =
reinterpret_cast<mirror::NativeArray<T>*>(data.data() + it.second);
for (uint32_t i = 0; i < num_ids; ++i) {
// We may not have relocations for some entries, in which case we'll
// just store null.
content_array->Set(i, visitor(content_array->Get(i), /* must_have_relocation= */ false));
}
}
template <typename Visitor>
void RelocateDexCacheArrays(mirror::DexCache* cache,
const DexFile& dex_file,
const Visitor& visitor)
REQUIRES_SHARED(Locks::mutator_lock_) {
mirror::NativeArray<ArtMethod>* old_method_array = cache->GetResolvedMethodsArray();
cache->SetResolvedMethodsArray(visitor(old_method_array));
RelocateNativeDexCacheArray(old_method_array, dex_file.NumMethodIds(), visitor);
mirror::NativeArray<ArtField>* old_field_array = cache->GetResolvedFieldsArray();
cache->SetResolvedFieldsArray(visitor(old_field_array));
RelocateNativeDexCacheArray(old_field_array, dex_file.NumFieldIds(), visitor);
mirror::GcRootArray<mirror::String>* old_strings_array = cache->GetStringsArray();
cache->SetStringsArray(visitor(old_strings_array));
// No need to relocate string entries in the array, we have already done this when
// creating the DexCache copy.
}
void RelocateNativePointers() {
ScopedTrace relocate_native_pointers("Relocate native pointers");
ScopedObjectAccess soa(Thread::Current());
NativePointerVisitor visitor(this);
for (auto it : classes_) {
mirror::Class* cls = reinterpret_cast<mirror::Class*>(&objects_[it.second]);
cls->FixupNativePointers(cls, kRuntimePointerSize, visitor);
RelocateMethodPointerArrays(cls, visitor);
}
for (auto it : native_relocations_) {
if (it.second.first == NativeRelocationKind::kImTable) {
ImTable* im_table = reinterpret_cast<ImTable*>(im_tables_.data() + it.second.second);
RelocateImTable(im_table, visitor);
}
}
for (auto it : dex_caches_) {
mirror::DexCache* cache = reinterpret_cast<mirror::DexCache*>(&objects_[it.second]);
RelocateDexCacheArrays(cache, *it.first, visitor);
}
}
void RelocateImTable(ImTable* im_table, const NativePointerVisitor& visitor) {
for (size_t i = 0; i < ImTable::kSize; ++i) {
ArtMethod* method = im_table->Get(i, kRuntimePointerSize);
ArtMethod* new_method = nullptr;
if (method->IsRuntimeMethod() && !IsInBootImage(method)) {
// New IMT conflict method: just use the boot image version.
// TODO: Consider copying the new IMT conflict method.
new_method = Runtime::Current()->GetImtConflictMethod();
DCHECK(IsInBootImage(new_method));
} else {
new_method = visitor(method);
}
if (method != new_method) {
im_table->Set(i, new_method, kRuntimePointerSize);
}
}
}
void CopyFieldArrays(ObjPtr<mirror::Class> cls, uint32_t class_image_address)
REQUIRES_SHARED(Locks::mutator_lock_) {
LengthPrefixedArray<ArtField>* fields[] = {
cls->GetSFieldsPtr(), cls->GetIFieldsPtr(),
};
for (LengthPrefixedArray<ArtField>* cur_fields : fields) {
if (cur_fields != nullptr) {
// Copy the array.
size_t number_of_fields = cur_fields->size();
size_t size = LengthPrefixedArray<ArtField>::ComputeSize(number_of_fields);
size_t offset = art_fields_.size();
art_fields_.resize(offset + size);
auto* dest_array =
reinterpret_cast<LengthPrefixedArray<ArtField>*>(art_fields_.data() + offset);
memcpy(dest_array, cur_fields, size);
native_relocations_[cur_fields] =
std::make_pair(NativeRelocationKind::kArtFieldArray, offset);
// Update the class pointer of individual fields.
for (size_t i = 0; i != number_of_fields; ++i) {
dest_array->At(i).GetDeclaringClassAddressWithoutBarrier()->Assign(
reinterpret_cast<mirror::Class*>(class_image_address));
}
}
}
}
void CopyMethodArrays(ObjPtr<mirror::Class> cls, uint32_t class_image_address)
REQUIRES_SHARED(Locks::mutator_lock_) {
size_t number_of_methods = cls->NumMethods();
if (number_of_methods == 0) {
return;
}
size_t size = LengthPrefixedArray<ArtMethod>::ComputeSize(number_of_methods);
size_t offset = art_methods_.size();
art_methods_.resize(offset + size);
auto* dest_array =
reinterpret_cast<LengthPrefixedArray<ArtMethod>*>(art_methods_.data() + offset);
memcpy(dest_array, cls->GetMethodsPtr(), size);
native_relocations_[cls->GetMethodsPtr()] =
std::make_pair(NativeRelocationKind::kArtMethodArray, offset);
for (size_t i = 0; i != number_of_methods; ++i) {
ArtMethod* method = &cls->GetMethodsPtr()->At(i);
ArtMethod* copy = &dest_array->At(i);
// Update the class pointer.
ObjPtr<mirror::Class> declaring_class = method->GetDeclaringClass();
if (declaring_class == cls) {
copy->GetDeclaringClassAddressWithoutBarrier()->Assign(
reinterpret_cast<mirror::Class*>(class_image_address));
} else {
DCHECK(method->IsCopied());
if (!IsInBootImage(declaring_class.Ptr())) {
DCHECK(classes_.find(declaring_class->GetClassDef()) != classes_.end());
copy->GetDeclaringClassAddressWithoutBarrier()->Assign(
reinterpret_cast<mirror::Class*>(
image_begin_ + sizeof(ImageHeader) + classes_[declaring_class->GetClassDef()]));
}
}
// Record the native relocation of the method.
uintptr_t copy_offset =
reinterpret_cast<uintptr_t>(copy) - reinterpret_cast<uintptr_t>(art_methods_.data());
native_relocations_[method] = std::make_pair(NativeRelocationKind::kArtMethod, copy_offset);
// Ignore the single-implementation info for abstract method.
if (method->IsAbstract()) {
copy->SetHasSingleImplementation(false);
copy->SetSingleImplementation(nullptr, kRuntimePointerSize);
}
// Set the entrypoint and data pointer of the method.
StubType stub;
if (method->IsNative()) {
stub = StubType::kQuickGenericJNITrampoline;
} else if (!cls->IsVerified()) {
stub = StubType::kQuickToInterpreterBridge;
} else if (method->NeedsClinitCheckBeforeCall()) {
stub = StubType::kQuickResolutionTrampoline;
} else {
stub = StubType::kNterpTrampoline;
}
const std::vector<gc::space::ImageSpace*>& image_spaces =
Runtime::Current()->GetHeap()->GetBootImageSpaces();
DCHECK(!image_spaces.empty());
const OatFile* oat_file = image_spaces[0]->GetOatFile();
DCHECK(oat_file != nullptr);
const OatHeader& header = oat_file->GetOatHeader();
copy->SetEntryPointFromQuickCompiledCode(header.GetOatAddress(stub));
if (method->IsNative()) {
StubType stub_type = method->IsCriticalNative()
? StubType::kJNIDlsymLookupCriticalTrampoline
: StubType::kJNIDlsymLookupTrampoline;
copy->SetEntryPointFromJni(header.GetOatAddress(stub_type));
} else if (method->IsInvokable()) {
DCHECK(method->HasCodeItem()) << method->PrettyMethod();
ptrdiff_t code_item_offset = reinterpret_cast<const uint8_t*>(method->GetCodeItem()) -
method->GetDexFile()->DataBegin();
copy->SetDataPtrSize(
reinterpret_cast<const void*>(code_item_offset), kRuntimePointerSize);
}
}
}
void CopyImTable(ObjPtr<mirror::Class> cls) REQUIRES_SHARED(Locks::mutator_lock_) {
ImTable* table = cls->GetImt(kRuntimePointerSize);
// If the table is null or shared and/or already emitted, we can skip.
if (table == nullptr || IsInBootImage(table) || HasNativeRelocation(table)) {
return;
}
const size_t size = ImTable::SizeInBytes(kRuntimePointerSize);
size_t offset = im_tables_.size();
im_tables_.resize(offset + size);
uint8_t* dest = im_tables_.data() + offset;
memcpy(dest, table, size);
native_relocations_[table] = std::make_pair(NativeRelocationKind::kImTable, offset);
}
bool HasNativeRelocation(void* ptr) const {
return native_relocations_.find(ptr) != native_relocations_.end();
}
static void LoadClassesFromReferenceProfile(
Thread* self,
const dchecked_vector<Handle<mirror::DexCache>>& dex_caches)
REQUIRES_SHARED(Locks::mutator_lock_) {
AppInfo* app_info = Runtime::Current()->GetAppInfo();
std::string profile_file = app_info->GetPrimaryApkReferenceProfile();
if (profile_file.empty()) {
return;
}
// Lock the file, it could be concurrently updated by the system. Don't block
// as this is app startup sensitive.
std::string error;
ScopedFlock profile =
LockedFile::Open(profile_file.c_str(), O_RDONLY, /*block=*/false, &error);
if (profile == nullptr) {
LOG(DEBUG) << "Couldn't lock the profile file " << profile_file << ": " << error;
return;
}
ProfileCompilationInfo profile_info(/* for_boot_image= */ false);
if (!profile_info.Load(profile->Fd())) {
LOG(DEBUG) << "Could not load profile file";
return;
}
StackHandleScope<1> hs(self);
Handle<mirror::ClassLoader> class_loader =
hs.NewHandle<mirror::ClassLoader>(dex_caches[0]->GetClassLoader());
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
ScopedTrace loading_classes("Loading classes from profile");
for (auto dex_cache : dex_caches) {
const DexFile* dex_file = dex_cache->GetDexFile();
const ArenaSet<dex::TypeIndex>* class_types = profile_info.GetClasses(*dex_file);
if (class_types == nullptr) {
// This means the profile file did not reference the dex file, which is the case
// if there's no classes and methods of that dex file in the profile.
continue;
}
for (dex::TypeIndex idx : *class_types) {
// The index is greater or equal to NumTypeIds if the type is an extra
// descriptor, not referenced by the dex file.
if (idx.index_ < dex_file->NumTypeIds()) {
ObjPtr<mirror::Class> klass = class_linker->ResolveType(idx, dex_cache, class_loader);
if (klass == nullptr) {
self->ClearException();
LOG(DEBUG) << "Failed to preload " << dex_file->PrettyType(idx);
continue;
}
}
}
}
}
bool WriteObjects(std::string* error_msg) {
ScopedTrace write_objects("Writing objects");
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
ScopedObjectAccess soa(Thread::Current());
VariableSizedHandleScope handles(soa.Self());
Handle<mirror::Class> object_array_class = handles.NewHandle(
GetClassRoot<mirror::ObjectArray<mirror::Object>>(class_linker));
Handle<mirror::ObjectArray<mirror::Object>> image_roots = handles.NewHandle(
mirror::ObjectArray<mirror::Object>::Alloc(
soa.Self(), object_array_class.Get(), ImageHeader::kImageRootsMax));
if (image_roots == nullptr) {
DCHECK(soa.Self()->IsExceptionPending());
soa.Self()->ClearException();
*error_msg = "Out of memory when trying to generate a runtime app image";
return false;
}
// Find the dex files that will be used for generating the app image.
dchecked_vector<Handle<mirror::DexCache>> dex_caches;
FindDexCaches(soa.Self(), dex_caches, handles);
if (dex_caches.size() == 0) {
*error_msg = "Did not find dex caches to generate an app image";
return false;
}
const OatDexFile* oat_dex_file = dex_caches[0]->GetDexFile()->GetOatDexFile();
VdexFile* vdex_file = oat_dex_file->GetOatFile()->GetVdexFile();
// The first entry in `dex_caches` contains the location of the primary APK.
dex_location_ = oat_dex_file->GetDexFileLocation();
size_t number_of_dex_files = vdex_file->GetNumberOfDexFiles();
if (number_of_dex_files != dex_caches.size()) {
// This means some dex files haven't been executed. For simplicity, just
// register them and recollect dex caches.
Handle<mirror::ClassLoader> loader = handles.NewHandle(dex_caches[0]->GetClassLoader());
VisitClassLoaderDexFiles(soa.Self(), loader, [&](const art::DexFile* dex_file)
REQUIRES_SHARED(Locks::mutator_lock_) {
class_linker->RegisterDexFile(*dex_file, dex_caches[0]->GetClassLoader());
return true; // Continue with other dex files.
});
dex_caches.clear();
FindDexCaches(soa.Self(), dex_caches, handles);
if (number_of_dex_files != dex_caches.size()) {
*error_msg = "Number of dex caches does not match number of dex files in the primary APK";
return false;
}
}
// If classes referenced in the reference profile are not loaded, preload
// them. This makes sure we generate a good runtime app image, even if this
// current app run did not load all startup classes.
LoadClassesFromReferenceProfile(soa.Self(), dex_caches);
// We store the checksums of the dex files used at runtime. These can be
// different compared to the vdex checksums due to compact dex.
std::vector<uint32_t> checksums(number_of_dex_files);
uint32_t checksum_index = 0;
for (const OatDexFile* current_oat_dex_file : oat_dex_file->GetOatFile()->GetOatDexFiles()) {
const DexFile::Header* header =
reinterpret_cast<const DexFile::Header*>(current_oat_dex_file->GetDexFilePointer());
checksums[checksum_index++] = header->checksum_;
}
DCHECK_EQ(checksum_index, number_of_dex_files);
// Create the fake OatHeader to store the dependencies of the image.
SafeMap<std::string, std::string> key_value_store;
Runtime* runtime = Runtime::Current();
key_value_store.Put(OatHeader::kApexVersionsKey, runtime->GetApexVersions());
key_value_store.Put(OatHeader::kBootClassPathKey,
android::base::Join(runtime->GetBootClassPathLocations(), ':'));
key_value_store.Put(OatHeader::kBootClassPathChecksumsKey,
runtime->GetBootClassPathChecksums());
key_value_store.Put(OatHeader::kClassPathKey,
oat_dex_file->GetOatFile()->GetClassLoaderContext());
std::unique_ptr<const InstructionSetFeatures> isa_features =
InstructionSetFeatures::FromCppDefines();
std::unique_ptr<OatHeader> oat_header(
OatHeader::Create(kRuntimeISA,
isa_features.get(),
number_of_dex_files,
&key_value_store));
// Create the byte array containing the oat header and dex checksums.
uint32_t checksums_size = checksums.size() * sizeof(uint32_t);
Handle<mirror::ByteArray> header_data = handles.NewHandle(
mirror::ByteArray::Alloc(soa.Self(), oat_header->GetHeaderSize() + checksums_size));
if (header_data == nullptr) {
DCHECK(soa.Self()->IsExceptionPending());
soa.Self()->ClearException();
*error_msg = "Out of memory when trying to generate a runtime app image";
return false;
}
memcpy(header_data->GetData(), oat_header.get(), oat_header->GetHeaderSize());
memcpy(header_data->GetData() + oat_header->GetHeaderSize(), checksums.data(), checksums_size);
// Create and populate the dex caches aray.
Handle<mirror::ObjectArray<mirror::Object>> dex_cache_array = handles.NewHandle(
mirror::ObjectArray<mirror::Object>::Alloc(
soa.Self(), object_array_class.Get(), dex_caches.size()));
if (dex_cache_array == nullptr) {
DCHECK(soa.Self()->IsExceptionPending());
soa.Self()->ClearException();
*error_msg = "Out of memory when trying to generate a runtime app image";
return false;
}
for (uint32_t i = 0; i < dex_caches.size(); ++i) {
dex_cache_array->Set(i, dex_caches[i].Get());
}
image_roots->Set(ImageHeader::kDexCaches, dex_cache_array.Get());
image_roots->Set(ImageHeader::kClassRoots, class_linker->GetClassRoots());
image_roots->Set(ImageHeader::kAppImageOatHeader, header_data.Get());
{
// Now that we have created all objects needed for the `image_roots`, copy
// it into the buffer. Note that this will recursively copy all objects
// contained in `image_roots`. That's acceptable as we don't have cycles,
// nor a deep graph.
ScopedAssertNoThreadSuspension sants("Writing runtime app image");
CopyObject(image_roots.Get());
}
// Emit classes defined in the app class loader (which will also indrirectly
// emit dex caches and their arrays).
EmitClasses(soa.Self(), dex_cache_array);
return true;
}
class FixupVisitor {
public:
FixupVisitor(RuntimeImageHelper* image, size_t copy_offset)
: image_(image), copy_offset_(copy_offset) {}
// We do not visit native roots. These are handled with other logic.
void VisitRootIfNonNull(mirror::CompressedReference<mirror::Object>* root ATTRIBUTE_UNUSED)
const {
LOG(FATAL) << "UNREACHABLE";
}
void VisitRoot(mirror::CompressedReference<mirror::Object>* root ATTRIBUTE_UNUSED) const {
LOG(FATAL) << "UNREACHABLE";
}
void operator()(ObjPtr<mirror::Object> obj,
MemberOffset offset,
bool is_static) const
REQUIRES_SHARED(Locks::mutator_lock_) {
// We don't copy static fields, instead classes will be marked as resolved
// and initialized at runtime.
ObjPtr<mirror::Object> ref =
is_static ? nullptr : obj->GetFieldObject<mirror::Object>(offset);
mirror::Object* address = image_->GetOrComputeImageAddress(ref.Ptr());
mirror::Object* copy =
reinterpret_cast<mirror::Object*>(image_->objects_.data() + copy_offset_);
copy->GetFieldObjectReferenceAddr<kVerifyNone>(offset)->Assign(address);
}
// java.lang.ref.Reference visitor.
void operator()(ObjPtr<mirror::Class> klass ATTRIBUTE_UNUSED,
ObjPtr<mirror::Reference> ref) const
REQUIRES_SHARED(Locks::mutator_lock_) {
operator()(ref, mirror::Reference::ReferentOffset(), /* is_static */ false);
}
private:
RuntimeImageHelper* image_;
size_t copy_offset_;
};
template <typename T>
void CopyNativeDexCacheArray(uint32_t num_entries,
uint32_t max_entries,
mirror::NativeArray<T>* array) {
if (array == nullptr) {
return;
}
size_t size = num_entries * sizeof(void*);
bool only_startup = !mirror::DexCache::ShouldAllocateFullArray(num_entries, max_entries);
std::vector<uint8_t>& data = only_startup ? metadata_ : dex_cache_arrays_;
NativeRelocationKind relocation_kind = only_startup
? NativeRelocationKind::kStartupNativeDexCacheArray
: NativeRelocationKind::kFullNativeDexCacheArray;
size_t offset = data.size() + sizeof(uint32_t);
data.resize(offset + size);
// We need to store `num_entries` because ImageSpace doesn't have
// access to the dex files when relocating dex caches.
reinterpret_cast<uint32_t*>(data.data() + offset)[-1] = num_entries;
memcpy(data.data() + offset, array, size);
native_relocations_[array] = std::make_pair(relocation_kind, offset);
}
template <typename T>
mirror::GcRootArray<T>* CreateGcRootDexCacheArray(uint32_t num_entries,
uint32_t max_entries,
mirror::GcRootArray<T>* array) {
if (array == nullptr) {
return nullptr;
}
size_t size = num_entries * sizeof(GcRoot<T>);
bool only_startup = !mirror::DexCache::ShouldAllocateFullArray(num_entries, max_entries);
std::vector<uint8_t>& data = only_startup ? metadata_ : dex_cache_arrays_;
NativeRelocationKind relocation_kind = only_startup
? NativeRelocationKind::kStartupNativeDexCacheArray
: NativeRelocationKind::kFullNativeDexCacheArray;
size_t offset = data.size() + sizeof(uint32_t);
data.resize(offset + size);
// We need to store `num_entries` because ImageSpace doesn't have
// access to the dex files when relocating dex caches.
reinterpret_cast<uint32_t*>(data.data() + offset)[-1] = num_entries;
native_relocations_[array] = std::make_pair(relocation_kind, offset);
return reinterpret_cast<mirror::GcRootArray<T>*>(data.data() + offset);
}
uint32_t CopyDexCache(ObjPtr<mirror::DexCache> cache) REQUIRES_SHARED(Locks::mutator_lock_) {
auto it = dex_caches_.find(cache->GetDexFile());
if (it != dex_caches_.end()) {
return it->second;
}
uint32_t offset = CopyObject(cache);
dex_caches_[cache->GetDexFile()] = offset;
// For dex caches, clear pointers to data that will be set at runtime.
mirror::Object* copy = reinterpret_cast<mirror::Object*>(objects_.data() + offset);
reinterpret_cast<mirror::DexCache*>(copy)->ResetNativeArrays();
reinterpret_cast<mirror::DexCache*>(copy)->SetDexFile(nullptr);
// Copy the ArtMethod array.
mirror::NativeArray<ArtMethod>* resolved_methods = cache->GetResolvedMethodsArray();
CopyNativeDexCacheArray(cache->GetDexFile()->NumMethodIds(),
mirror::DexCache::kDexCacheMethodCacheSize,
resolved_methods);
// Store the array pointer in the dex cache, which will be relocated at the end.
reinterpret_cast<mirror::DexCache*>(copy)->SetResolvedMethodsArray(resolved_methods);
// Copy the ArtField array.
mirror::NativeArray<ArtField>* resolved_fields = cache->GetResolvedFieldsArray();
CopyNativeDexCacheArray(cache->GetDexFile()->NumFieldIds(),
mirror::DexCache::kDexCacheFieldCacheSize,
resolved_fields);
// Store the array pointer in the dex cache, which will be relocated at the end.
reinterpret_cast<mirror::DexCache*>(copy)->SetResolvedFieldsArray(resolved_fields);
// Copy the string array.
mirror::GcRootArray<mirror::String>* strings = cache->GetStringsArray();
mirror::GcRootArray<mirror::String>* new_strings =
CreateGcRootDexCacheArray(cache->GetDexFile()->NumStringIds(),
mirror::DexCache::kDexCacheStringCacheSize,
strings);
// Store the array pointer in the dex cache, which will be relocated at the end.
reinterpret_cast<mirror::DexCache*>(copy)->SetStringsArray(strings);
// The code below copies new objects, so invalidate the address we have for
// `copy`.
copy = nullptr;
if (strings != nullptr) {
for (uint32_t i = 0; i < cache->GetDexFile()->NumStringIds(); ++i) {
ObjPtr<mirror::String> str = strings->Get(i);
if (str == nullptr || IsInBootImage(str.Ptr())) {
new_strings->Set(i, str.Ptr());
} else {
uint32_t hash = static_cast<uint32_t>(str->GetStoredHashCode());
DCHECK_EQ(hash, static_cast<uint32_t>(str->ComputeHashCode()))
<< "Dex cache strings should be interned";
auto it2 = intern_table_.FindWithHash(str.Ptr(), hash);
if (it2 == intern_table_.end()) {
uint32_t string_offset = CopyObject(str);
uint32_t address = image_begin_ + string_offset + sizeof(ImageHeader);
intern_table_.InsertWithHash(address, hash);
new_strings->Set(i, reinterpret_cast<mirror::String*>(address));
} else {
new_strings->Set(i, reinterpret_cast<mirror::String*>(*it2));
}
// To not confuse string references from the dex cache object and
// string references from the array, we put an offset bigger than the
// size of a DexCache object. ClassLinker::VisitInternedStringReferences
// knows how to decode this offset.
string_reference_offsets_.emplace_back(
sizeof(ImageHeader) + offset, sizeof(mirror::DexCache) + i);
}
}
}
return offset;
}
uint32_t CopyClass(ObjPtr<mirror::Class> cls) REQUIRES_SHARED(Locks::mutator_lock_) {
const dex::ClassDef* class_def = cls->GetClassDef();
auto it = classes_.find(class_def);
if (it != classes_.end()) {
return it->second;
}
uint32_t offset = CopyObject(cls);
classes_[class_def] = offset;
uint32_t hash = cls->DescriptorHash();
// Save the hash, the `HashSet` implementation requires to find it.
class_hashes_[offset] = hash;
uint32_t class_image_address = image_begin_ + sizeof(ImageHeader) + offset;
bool inserted =
class_table_.InsertWithHash(ClassTable::TableSlot(class_image_address, hash), hash).second;
DCHECK(inserted) << "Class " << cls->PrettyDescriptor()
<< " (" << cls.Ptr() << ") already inserted";
// Clear internal state.
mirror::Class* copy = reinterpret_cast<mirror::Class*>(objects_.data() + offset);
copy->SetClinitThreadId(static_cast<pid_t>(0u));
copy->SetStatusInternal(cls->IsVerified() ? ClassStatus::kVerified : ClassStatus::kResolved);
copy->SetObjectSizeAllocFastPath(std::numeric_limits<uint32_t>::max());
copy->SetAccessFlags(copy->GetAccessFlags() & ~kAccRecursivelyInitialized);
// Clear static field values.
MemberOffset static_offset = cls->GetFirstReferenceStaticFieldOffset(kRuntimePointerSize);
memset(objects_.data() + offset + static_offset.Uint32Value(),
0,
cls->GetClassSize() - static_offset.Uint32Value());
CopyFieldArrays(cls, class_image_address);
CopyMethodArrays(cls, class_image_address);
if (cls->ShouldHaveImt()) {
CopyImTable(cls);
}
return offset;
}
// Copy `obj` in `objects_` and relocate references. Returns the offset
// within our buffer.
uint32_t CopyObject(ObjPtr<mirror::Object> obj) REQUIRES_SHARED(Locks::mutator_lock_) {
// Copy the object in `objects_`.
size_t object_size = obj->SizeOf();
size_t offset = objects_.size();
DCHECK(IsAligned<kObjectAlignment>(offset));
object_offsets_.push_back(offset);
objects_.resize(RoundUp(offset + object_size, kObjectAlignment));
memcpy(objects_.data() + offset, obj.Ptr(), object_size);
object_section_size_ += RoundUp(object_size, kObjectAlignment);
// Fixup reference pointers.
FixupVisitor visitor(this, offset);
obj->VisitReferences</*kVisitNativeRoots=*/ false>(visitor, visitor);
mirror::Object* copy = reinterpret_cast<mirror::Object*>(objects_.data() + offset);
// Clear any lockword data.
copy->SetLockWord(LockWord::Default(), /* as_volatile= */ false);
if (obj->IsString()) {
// Ensure a string always has a hashcode stored. This is checked at
// runtime because boot images don't want strings dirtied due to hashcode.
reinterpret_cast<mirror::String*>(copy)->GetHashCode();
}
return offset;
}
class CollectDexCacheVisitor : public DexCacheVisitor {
public:
explicit CollectDexCacheVisitor(VariableSizedHandleScope& handles) : handles_(handles) {}
void Visit(ObjPtr<mirror::DexCache> dex_cache)
REQUIRES_SHARED(Locks::dex_lock_, Locks::mutator_lock_) override {
dex_caches_.push_back(handles_.NewHandle(dex_cache));
}
const std::vector<Handle<mirror::DexCache>>& GetDexCaches() const {
return dex_caches_;
}
private:
VariableSizedHandleScope& handles_;
std::vector<Handle<mirror::DexCache>> dex_caches_;
};
// Find dex caches corresponding to the primary APK.
void FindDexCaches(Thread* self,
dchecked_vector<Handle<mirror::DexCache>>& dex_caches,
VariableSizedHandleScope& handles)
REQUIRES_SHARED(Locks::mutator_lock_) {
ScopedTrace trace("Find dex caches");
DCHECK(dex_caches.empty());
// Collect all dex caches.
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
CollectDexCacheVisitor visitor(handles);
{
ReaderMutexLock mu(self, *Locks::dex_lock_);
class_linker->VisitDexCaches(&visitor);
}
// Find the primary APK.
AppInfo* app_info = Runtime::Current()->GetAppInfo();
for (Handle<mirror::DexCache> cache : visitor.GetDexCaches()) {
if (app_info->GetRegisteredCodeType(cache->GetDexFile()->GetLocation()) ==
AppInfo::CodeType::kPrimaryApk) {
dex_caches.push_back(handles.NewHandle(cache.Get()));
break;
}
}
if (dex_caches.empty()) {
return;
}
const OatDexFile* oat_dex_file = dex_caches[0]->GetDexFile()->GetOatDexFile();
if (oat_dex_file == nullptr) {
// We need a .oat file for loading an app image;
dex_caches.clear();
return;
}
// Store the dex caches in the order in which their corresponding dex files
// are stored in the oat file. When we check for checksums at the point of
// loading the image, we rely on this order.
for (const OatDexFile* current : oat_dex_file->GetOatFile()->GetOatDexFiles()) {
if (current != oat_dex_file) {
for (Handle<mirror::DexCache> cache : visitor.GetDexCaches()) {
if (cache->GetDexFile()->GetOatDexFile() == current) {
dex_caches.push_back(handles.NewHandle(cache.Get()));
}
}
}
}
}
static uint64_t PointerToUint64(void* ptr) {
return reinterpret_cast64<uint64_t>(ptr);
}
void WriteImageMethods() {
ScopedObjectAccess soa(Thread::Current());
// We can just use plain runtime pointers.
Runtime* runtime = Runtime::Current();
header_.image_methods_[ImageHeader::kResolutionMethod] =
PointerToUint64(runtime->GetResolutionMethod());
header_.image_methods_[ImageHeader::kImtConflictMethod] =
PointerToUint64(runtime->GetImtConflictMethod());
header_.image_methods_[ImageHeader::kImtUnimplementedMethod] =
PointerToUint64(runtime->GetImtUnimplementedMethod());
header_.image_methods_[ImageHeader::kSaveAllCalleeSavesMethod] =
PointerToUint64(runtime->GetCalleeSaveMethod(CalleeSaveType::kSaveAllCalleeSaves));
header_.image_methods_[ImageHeader::kSaveRefsOnlyMethod] =
PointerToUint64(runtime->GetCalleeSaveMethod(CalleeSaveType::kSaveRefsOnly));
header_.image_methods_[ImageHeader::kSaveRefsAndArgsMethod] =
PointerToUint64(runtime->GetCalleeSaveMethod(CalleeSaveType::kSaveRefsAndArgs));
header_.image_methods_[ImageHeader::kSaveEverythingMethod] =
PointerToUint64(runtime->GetCalleeSaveMethod(CalleeSaveType::kSaveEverything));
header_.image_methods_[ImageHeader::kSaveEverythingMethodForClinit] =
PointerToUint64(runtime->GetCalleeSaveMethod(CalleeSaveType::kSaveEverythingForClinit));
header_.image_methods_[ImageHeader::kSaveEverythingMethodForSuspendCheck] =
PointerToUint64(
runtime->GetCalleeSaveMethod(CalleeSaveType::kSaveEverythingForSuspendCheck));
}
// Header for the image, created at the end once we know the size of all
// sections.
ImageHeader header_;
// Contents of the various sections.
std::vector<uint8_t> objects_;
std::vector<uint8_t> art_fields_;
std::vector<uint8_t> art_methods_;
std::vector<uint8_t> im_tables_;
std::vector<uint8_t> metadata_;
std::vector<uint8_t> dex_cache_arrays_;
std::vector<AppImageReferenceOffsetInfo> string_reference_offsets_;
// Bitmap of live objects in `objects_`. Populated from `object_offsets_`
// once we know `object_section_size`.
gc::accounting::ContinuousSpaceBitmap image_bitmap_;
// Sections stored in the header.
dchecked_vector<ImageSection> sections_;
// A list of offsets in `objects_` where objects begin.
std::vector<uint32_t> object_offsets_;
std::map<const dex::ClassDef*, uint32_t> classes_;
std::map<const DexFile*, uint32_t> dex_caches_;
std::map<uint32_t, uint32_t> class_hashes_;
std::map<void*, std::pair<NativeRelocationKind, uint32_t>> native_relocations_;
// Cached values of boot image information.
const uint32_t boot_image_begin_;
const uint32_t boot_image_size_;
// Where the image begins: just after the boot image.
const uint32_t image_begin_;
// Size of the `kSectionObjects` section.
size_t object_section_size_;
// The location of the primary APK / dex file.
std::string dex_location_;
// The intern table for strings that we will write to disk.
InternTableSet intern_table_;
// The class table holding classes that we will write to disk.
ClassTableSet class_table_;
friend class ClassDescriptorHash;
friend class PruneVisitor;
friend class NativePointerVisitor;
};
static std::string GetOatPath() {
const std::string& data_dir = Runtime::Current()->GetProcessDataDirectory();
if (data_dir.empty()) {
// The data ditectory is empty for tests.
return "";
}
return data_dir + "/cache/oat_primary/";
}
// Note: this may return a relative path for tests.
std::string RuntimeImage::GetRuntimeImagePath(const std::string& dex_location) {
std::string basename = android::base::Basename(dex_location);
std::string filename = ReplaceFileExtension(basename, "art");
return GetOatPath() + GetInstructionSetString(kRuntimeISA) + "/" + filename;
}
static bool EnsureDirectoryExists(const std::string& directory, std::string* error_msg) {
if (!OS::DirectoryExists(directory.c_str())) {
static constexpr mode_t kDirectoryMode = S_IRWXU | S_IRGRP | S_IXGRP| S_IROTH | S_IXOTH;
if (mkdir(directory.c_str(), kDirectoryMode) != 0) {
*error_msg =
StringPrintf("Could not create directory %s: %s", directory.c_str(), strerror(errno));
return false;
}
}
return true;
}
bool RuntimeImage::WriteImageToDisk(std::string* error_msg) {
gc::Heap* heap = Runtime::Current()->GetHeap();
if (!heap->HasBootImageSpace()) {
*error_msg = "Cannot generate an app image without a boot image";
return false;
}
std::string oat_path = GetOatPath();
if (!oat_path.empty() && !EnsureDirectoryExists(oat_path, error_msg)) {
return false;
}
ScopedTrace generate_image_trace("Generating runtime image");
RuntimeImageHelper image(heap);
if (!image.Generate(error_msg)) {
return false;
}
ScopedTrace write_image_trace("Writing runtime image to disk");
const std::string path = GetRuntimeImagePath(image.GetDexLocation());
if (!EnsureDirectoryExists(android::base::Dirname(path), error_msg)) {
return false;
}
// We first generate the app image in a temporary file, which we will then
// move to `path`.
const std::string temp_path = ReplaceFileExtension(path, std::to_string(getpid()) + ".tmp");
std::unique_ptr<File> out(OS::CreateEmptyFileWriteOnly(temp_path.c_str()));
if (out == nullptr) {
*error_msg = "Could not open " + temp_path + " for writing";
return false;
}
// Write objects. The header is written at the end in case we get killed.
if (out->Write(reinterpret_cast<const char*>(image.GetObjects().data()),
image.GetObjects().size(),
sizeof(ImageHeader)) != static_cast<int64_t>(image.GetObjects().size())) {
*error_msg = "Could not write image data to " + temp_path;
out->Erase(/*unlink=*/true);
return false;
}
{
// Write fields.
auto fields_section = image.GetHeader().GetImageSection(ImageHeader::kSectionArtFields);
if (out->Write(reinterpret_cast<const char*>(image.GetArtFields().data()),
fields_section.Size(),
fields_section.Offset()) != fields_section.Size()) {
*error_msg = "Could not write fields section " + temp_path;
out->Erase(/*unlink=*/true);
return false;
}
}
{
// Write methods.
auto methods_section = image.GetHeader().GetImageSection(ImageHeader::kSectionArtMethods);
if (out->Write(reinterpret_cast<const char*>(image.GetArtMethods().data()),
methods_section.Size(),
methods_section.Offset()) != methods_section.Size()) {
*error_msg = "Could not write methods section " + temp_path;
out->Erase(/*unlink=*/true);
return false;
}
}
{
// Write im tables.
auto im_tables_section = image.GetHeader().GetImageSection(ImageHeader::kSectionImTables);
if (out->Write(reinterpret_cast<const char*>(image.GetImTables().data()),
im_tables_section.Size(),
im_tables_section.Offset()) != im_tables_section.Size()) {
*error_msg = "Could not write ImTable section " + temp_path;
out->Erase(/*unlink=*/true);
return false;
}
}
{
// Write intern string set.
auto intern_section = image.GetHeader().GetImageSection(ImageHeader::kSectionInternedStrings);
std::vector<uint8_t> intern_data(intern_section.Size());
image.GenerateInternData(intern_data);
if (out->Write(reinterpret_cast<const char*>(intern_data.data()),
intern_section.Size(),
intern_section.Offset()) != intern_section.Size()) {
*error_msg = "Could not write intern section " + temp_path;
out->Erase(/*unlink=*/true);
return false;
}
}
{
// Write class table.
auto class_table_section = image.GetHeader().GetImageSection(ImageHeader::kSectionClassTable);
std::vector<uint8_t> class_table_data(class_table_section.Size());
image.GenerateClassTableData(class_table_data);
if (out->Write(reinterpret_cast<const char*>(class_table_data.data()),
class_table_section.Size(),
class_table_section.Offset()) != class_table_section.Size()) {
*error_msg = "Could not write class table section " + temp_path;
out->Erase(/*unlink=*/true);
return false;
}
}
// Write bitmap.
auto bitmap_section = image.GetHeader().GetImageSection(ImageHeader::kSectionImageBitmap);
if (out->Write(reinterpret_cast<const char*>(image.GetImageBitmap().Begin()),
bitmap_section.Size(),
bitmap_section.Offset()) != bitmap_section.Size()) {
*error_msg = "Could not write image bitmap " + temp_path;
out->Erase(/*unlink=*/true);
return false;
}
// Write metadata section.
auto metadata_section = image.GetHeader().GetImageSection(ImageHeader::kSectionMetadata);
if (out->Write(reinterpret_cast<const char*>(image.GetMetadata().data()),
metadata_section.Size(),
metadata_section.Offset()) != metadata_section.Size()) {
*error_msg = "Could not write metadata " + temp_path;
out->Erase(/*unlink=*/true);
return false;
}
// Write string offset array section.
auto string_offsets_section =
image.GetHeader().GetImageSection(ImageHeader::kSectionStringReferenceOffsets);
if (out->Write(reinterpret_cast<const char*>(image.GetStringReferenceOffsets().data()),
string_offsets_section.Size(),
string_offsets_section.Offset()) != string_offsets_section.Size()) {
*error_msg = "Could not write string reference offsets " + temp_path;
out->Erase(/*unlink=*/true);
return false;
}
// Write dex cache array section.
auto dex_cache_section = image.GetHeader().GetImageSection(ImageHeader::kSectionDexCacheArrays);
if (out->Write(reinterpret_cast<const char*>(image.GetDexCacheArrays().data()),
dex_cache_section.Size(),
dex_cache_section.Offset()) != dex_cache_section.Size()) {
*error_msg = "Could not write dex cache arrays " + temp_path;
out->Erase(/*unlink=*/true);
return false;
}
// Now write header.
if (out->Write(reinterpret_cast<const char*>(&image.GetHeader()), sizeof(ImageHeader), 0u) !=
sizeof(ImageHeader)) {
*error_msg = "Could not write image header to " + temp_path;
out->Erase(/*unlink=*/true);
return false;
}
if (out->FlushClose() != 0) {
*error_msg = "Could not flush and close " + temp_path;
// Unlink directly: we cannot use `out` as we may have closed it.
unlink(temp_path.c_str());
return false;
}
if (rename(temp_path.c_str(), path.c_str()) != 0) {
*error_msg =
"Failed to move runtime app image to " + path + ": " + std::string(strerror(errno));
// Unlink directly: we cannot use `out` as we have closed it.
unlink(temp_path.c_str());
return false;
}
return true;
}
} // namespace art