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android / platform / art / d63420863dd2ac68881c03f953275e9569815c8e / . / compiler / image_writer.cc
blob: c747ffa65b9848ea549273b99f5bfa86d00c9c10 [file] [log] [blame]
/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "image_writer.h"
#include <sys/stat.h>
#include <lz4.h>
#include <lz4hc.h>
#include <memory>
#include <numeric>
#include <unordered_set>
#include <vector>
#include "art_field-inl.h"
#include "art_method-inl.h"
#include "base/logging.h"
#include "base/unix_file/fd_file.h"
#include "class_linker-inl.h"
#include "compiled_method.h"
#include "dex_file-inl.h"
#include "driver/compiler_driver.h"
#include "elf_file.h"
#include "elf_utils.h"
#include "elf_writer.h"
#include "gc/accounting/card_table-inl.h"
#include "gc/accounting/heap_bitmap.h"
#include "gc/accounting/space_bitmap-inl.h"
#include "gc/heap.h"
#include "gc/space/large_object_space.h"
#include "gc/space/space-inl.h"
#include "globals.h"
#include "image.h"
#include "intern_table.h"
#include "linear_alloc.h"
#include "lock_word.h"
#include "mirror/abstract_method.h"
#include "mirror/array-inl.h"
#include "mirror/class-inl.h"
#include "mirror/class_loader.h"
#include "mirror/dex_cache-inl.h"
#include "mirror/method.h"
#include "mirror/object-inl.h"
#include "mirror/object_array-inl.h"
#include "mirror/string-inl.h"
#include "oat.h"
#include "oat_file.h"
#include "oat_file_manager.h"
#include "runtime.h"
#include "scoped_thread_state_change.h"
#include "handle_scope-inl.h"
#include "utils/dex_cache_arrays_layout-inl.h"
using ::art::mirror::Class;
using ::art::mirror::DexCache;
using ::art::mirror::Object;
using ::art::mirror::ObjectArray;
using ::art::mirror::String;
namespace art {
// Separate objects into multiple bins to optimize dirty memory use.
static constexpr bool kBinObjects = true;
// Return true if an object is already in an image space.
bool ImageWriter::IsInBootImage(const void* obj) const {
gc::Heap* const heap = Runtime::Current()->GetHeap();
if (!compile_app_image_) {
DCHECK(heap->GetBootImageSpaces().empty());
return false;
}
for (gc::space::ImageSpace* boot_image_space : heap->GetBootImageSpaces()) {
const uint8_t* image_begin = boot_image_space->Begin();
// Real image end including ArtMethods and ArtField sections.
const uint8_t* image_end = image_begin + boot_image_space->GetImageHeader().GetImageSize();
if (image_begin <= obj && obj < image_end) {
return true;
}
}
return false;
}
bool ImageWriter::IsInBootOatFile(const void* ptr) const {
gc::Heap* const heap = Runtime::Current()->GetHeap();
if (!compile_app_image_) {
DCHECK(heap->GetBootImageSpaces().empty());
return false;
}
for (gc::space::ImageSpace* boot_image_space : heap->GetBootImageSpaces()) {
const ImageHeader& image_header = boot_image_space->GetImageHeader();
if (image_header.GetOatFileBegin() <= ptr && ptr < image_header.GetOatFileEnd()) {
return true;
}
}
return false;
}
static void CheckNoDexObjectsCallback(Object* obj, void* arg ATTRIBUTE_UNUSED)
SHARED_REQUIRES(Locks::mutator_lock_) {
Class* klass = obj->GetClass();
CHECK_NE(PrettyClass(klass), "com.android.dex.Dex");
}
static void CheckNoDexObjects() {
ScopedObjectAccess soa(Thread::Current());
Runtime::Current()->GetHeap()->VisitObjects(CheckNoDexObjectsCallback, nullptr);
}
bool ImageWriter::PrepareImageAddressSpace() {
target_ptr_size_ = InstructionSetPointerSize(compiler_driver_.GetInstructionSet());
gc::Heap* const heap = Runtime::Current()->GetHeap();
{
ScopedObjectAccess soa(Thread::Current());
PruneNonImageClasses(); // Remove junk
if (!compile_app_image_) {
// Avoid for app image since this may increase RAM and image size.
ComputeLazyFieldsForImageClasses(); // Add useful information
}
}
heap->CollectGarbage(false); // Remove garbage.
// Dex caches must not have their dex fields set in the image. These are memory buffers of mapped
// dex files.
//
// We may open them in the unstarted-runtime code for class metadata. Their fields should all be
// reset in PruneNonImageClasses and the objects reclaimed in the GC. Make sure that's actually
// true.
if (kIsDebugBuild) {
CheckNoDexObjects();
}
if (kIsDebugBuild) {
ScopedObjectAccess soa(Thread::Current());
CheckNonImageClassesRemoved();
}
{
ScopedObjectAccess soa(Thread::Current());
CalculateNewObjectOffsets();
}
// This needs to happen after CalculateNewObjectOffsets since it relies on intern_table_bytes_ and
// bin size sums being calculated.
if (!AllocMemory()) {
return false;
}
return true;
}
bool ImageWriter::Write(int image_fd,
const std::vector<const char*>& image_filenames,
const std::vector<const char*>& oat_filenames) {
// If image_fd or oat_fd are not kInvalidFd then we may have empty strings in image_filenames or
// oat_filenames.
CHECK(!image_filenames.empty());
if (image_fd != kInvalidFd) {
CHECK_EQ(image_filenames.size(), 1u);
}
CHECK(!oat_filenames.empty());
CHECK_EQ(image_filenames.size(), oat_filenames.size());
{
ScopedObjectAccess soa(Thread::Current());
for (size_t i = 0; i < oat_filenames.size(); ++i) {
CreateHeader(i);
CopyAndFixupNativeData(i);
}
}
{
// TODO: heap validation can't handle these fix up passes.
ScopedObjectAccess soa(Thread::Current());
Runtime::Current()->GetHeap()->DisableObjectValidation();
CopyAndFixupObjects();
}
for (size_t i = 0; i < image_filenames.size(); ++i) {
const char* image_filename = image_filenames[i];
ImageInfo& image_info = GetImageInfo(i);
std::unique_ptr<File> image_file;
if (image_fd != kInvalidFd) {
if (strlen(image_filename) == 0u) {
image_file.reset(new File(image_fd, unix_file::kCheckSafeUsage));
// Empty the file in case it already exists.
if (image_file != nullptr) {
TEMP_FAILURE_RETRY(image_file->SetLength(0));
TEMP_FAILURE_RETRY(image_file->Flush());
}
} else {
LOG(ERROR) << "image fd " << image_fd << " name " << image_filename;
}
} else {
image_file.reset(OS::CreateEmptyFile(image_filename));
}
if (image_file == nullptr) {
LOG(ERROR) << "Failed to open image file " << image_filename;
return false;
}
if (!compile_app_image_ && fchmod(image_file->Fd(), 0644) != 0) {
PLOG(ERROR) << "Failed to make image file world readable: " << image_filename;
image_file->Erase();
return EXIT_FAILURE;
}
std::unique_ptr<char[]> compressed_data;
// Image data size excludes the bitmap and the header.
ImageHeader* const image_header = reinterpret_cast<ImageHeader*>(image_info.image_->Begin());
const size_t image_data_size = image_header->GetImageSize() - sizeof(ImageHeader);
char* image_data = reinterpret_cast<char*>(image_info.image_->Begin()) + sizeof(ImageHeader);
size_t data_size;
const char* image_data_to_write;
const uint64_t compress_start_time = NanoTime();
CHECK_EQ(image_header->storage_mode_, image_storage_mode_);
switch (image_storage_mode_) {
case ImageHeader::kStorageModeLZ4HC: // Fall-through.
case ImageHeader::kStorageModeLZ4: {
const size_t compressed_max_size = LZ4_compressBound(image_data_size);
compressed_data.reset(new char[compressed_max_size]);
data_size = LZ4_compress(
reinterpret_cast<char*>(image_info.image_->Begin()) + sizeof(ImageHeader),
&compressed_data[0],
image_data_size);
break;
}
/*
* Disabled due to image_test64 flakyness. Both use same decompression. b/27560444
case ImageHeader::kStorageModeLZ4HC: {
// Bound is same as non HC.
const size_t compressed_max_size = LZ4_compressBound(image_data_size);
compressed_data.reset(new char[compressed_max_size]);
data_size = LZ4_compressHC(
reinterpret_cast<char*>(image_info.image_->Begin()) + sizeof(ImageHeader),
&compressed_data[0],
image_data_size);
break;
}
*/
case ImageHeader::kStorageModeUncompressed: {
data_size = image_data_size;
image_data_to_write = image_data;
break;
}
default: {
LOG(FATAL) << "Unsupported";
UNREACHABLE();
}
}
if (compressed_data != nullptr) {
image_data_to_write = &compressed_data[0];
VLOG(compiler) << "Compressed from " << image_data_size << " to " << data_size << " in "
<< PrettyDuration(NanoTime() - compress_start_time);
if (kIsDebugBuild) {
std::unique_ptr<uint8_t[]> temp(new uint8_t[image_data_size]);
const size_t decompressed_size = LZ4_decompress_safe(
reinterpret_cast<char*>(&compressed_data[0]),
reinterpret_cast<char*>(&temp[0]),
data_size,
image_data_size);
CHECK_EQ(decompressed_size, image_data_size);
CHECK_EQ(memcmp(image_data, &temp[0], image_data_size), 0) << image_storage_mode_;
}
}
// Write out the image + fields + methods.
const bool is_compressed = compressed_data != nullptr;
if (!image_file->PwriteFully(image_data_to_write, data_size, sizeof(ImageHeader))) {
PLOG(ERROR) << "Failed to write image file data " << image_filename;
image_file->Erase();
return false;
}
// Write out the image bitmap at the page aligned start of the image end, also uncompressed for
// convenience.
const ImageSection& bitmap_section = image_header->GetImageSection(
ImageHeader::kSectionImageBitmap);
// Align up since data size may be unaligned if the image is compressed.
size_t bitmap_position_in_file = RoundUp(sizeof(ImageHeader) + data_size, kPageSize);
if (!is_compressed) {
CHECK_EQ(bitmap_position_in_file, bitmap_section.Offset());
}
if (!image_file->PwriteFully(reinterpret_cast<char*>(image_info.image_bitmap_->Begin()),
bitmap_section.Size(),
bitmap_position_in_file)) {
PLOG(ERROR) << "Failed to write image file " << image_filename;
image_file->Erase();
return false;
}
int err = image_file->Flush();
if (err < 0) {
PLOG(ERROR) << "Failed to flush image file " << image_filename << " with result " << err;
image_file->Erase();
return false;
}
// Write header last in case the compiler gets killed in the middle of image writing.
// We do not want to have a corrupted image with a valid header.
// The header is uncompressed since it contains whether the image is compressed or not.
image_header->data_size_ = data_size;
if (!image_file->PwriteFully(reinterpret_cast<char*>(image_info.image_->Begin()),
sizeof(ImageHeader),
0)) {
PLOG(ERROR) << "Failed to write image file header " << image_filename;
image_file->Erase();
return false;
}
CHECK_EQ(bitmap_position_in_file + bitmap_section.Size(),
static_cast<size_t>(image_file->GetLength()));
if (image_file->FlushCloseOrErase() != 0) {
PLOG(ERROR) << "Failed to flush and close image file " << image_filename;
return false;
}
}
return true;
}
void ImageWriter::SetImageOffset(mirror::Object* object, size_t offset) {
DCHECK(object != nullptr);
DCHECK_NE(offset, 0U);
// The object is already deflated from when we set the bin slot. Just overwrite the lock word.
object->SetLockWord(LockWord::FromForwardingAddress(offset), false);
DCHECK_EQ(object->GetLockWord(false).ReadBarrierState(), 0u);
DCHECK(IsImageOffsetAssigned(object));
}
void ImageWriter::UpdateImageOffset(mirror::Object* obj, uintptr_t offset) {
DCHECK(IsImageOffsetAssigned(obj)) << obj << " " << offset;
obj->SetLockWord(LockWord::FromForwardingAddress(offset), false);
DCHECK_EQ(obj->GetLockWord(false).ReadBarrierState(), 0u);
}
void ImageWriter::AssignImageOffset(mirror::Object* object, ImageWriter::BinSlot bin_slot) {
DCHECK(object != nullptr);
DCHECK_NE(image_objects_offset_begin_, 0u);
size_t oat_index = GetOatIndex(object);
ImageInfo& image_info = GetImageInfo(oat_index);
size_t bin_slot_offset = image_info.bin_slot_offsets_[bin_slot.GetBin()];
size_t new_offset = bin_slot_offset + bin_slot.GetIndex();
DCHECK_ALIGNED(new_offset, kObjectAlignment);
SetImageOffset(object, new_offset);
DCHECK_LT(new_offset, image_info.image_end_);
}
bool ImageWriter::IsImageOffsetAssigned(mirror::Object* object) const {
// Will also return true if the bin slot was assigned since we are reusing the lock word.
DCHECK(object != nullptr);
return object->GetLockWord(false).GetState() == LockWord::kForwardingAddress;
}
size_t ImageWriter::GetImageOffset(mirror::Object* object) const {
DCHECK(object != nullptr);
DCHECK(IsImageOffsetAssigned(object));
LockWord lock_word = object->GetLockWord(false);
size_t offset = lock_word.ForwardingAddress();
size_t oat_index = GetOatIndex(object);
const ImageInfo& image_info = GetImageInfo(oat_index);
DCHECK_LT(offset, image_info.image_end_);
return offset;
}
void ImageWriter::SetImageBinSlot(mirror::Object* object, BinSlot bin_slot) {
DCHECK(object != nullptr);
DCHECK(!IsImageOffsetAssigned(object));
DCHECK(!IsImageBinSlotAssigned(object));
// Before we stomp over the lock word, save the hash code for later.
Monitor::Deflate(Thread::Current(), object);;
LockWord lw(object->GetLockWord(false));
switch (lw.GetState()) {
case LockWord::kFatLocked: {
LOG(FATAL) << "Fat locked object " << object << " found during object copy";
break;
}
case LockWord::kThinLocked: {
LOG(FATAL) << "Thin locked object " << object << " found during object copy";
break;
}
case LockWord::kUnlocked:
// No hash, don't need to save it.
break;
case LockWord::kHashCode:
DCHECK(saved_hashcode_map_.find(object) == saved_hashcode_map_.end());
saved_hashcode_map_.emplace(object, lw.GetHashCode());
break;
default:
LOG(FATAL) << "Unreachable.";
UNREACHABLE();
}
object->SetLockWord(LockWord::FromForwardingAddress(bin_slot.Uint32Value()), false);
DCHECK_EQ(object->GetLockWord(false).ReadBarrierState(), 0u);
DCHECK(IsImageBinSlotAssigned(object));
}
void ImageWriter::PrepareDexCacheArraySlots() {
// Prepare dex cache array starts based on the ordering specified in the CompilerDriver.
// Set the slot size early to avoid DCHECK() failures in IsImageBinSlotAssigned()
// when AssignImageBinSlot() assigns their indexes out or order.
for (const DexFile* dex_file : compiler_driver_.GetDexFilesForOatFile()) {
auto it = dex_file_oat_index_map_.find(dex_file);
DCHECK(it != dex_file_oat_index_map_.end()) << dex_file->GetLocation();
ImageInfo& image_info = GetImageInfo(it->second);
image_info.dex_cache_array_starts_.Put(dex_file, image_info.bin_slot_sizes_[kBinDexCacheArray]);
DexCacheArraysLayout layout(target_ptr_size_, dex_file);
image_info.bin_slot_sizes_[kBinDexCacheArray] += layout.Size();
}
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
Thread* const self = Thread::Current();
ReaderMutexLock mu(self, *class_linker->DexLock());
for (const ClassLinker::DexCacheData& data : class_linker->GetDexCachesData()) {
mirror::DexCache* dex_cache =
down_cast<mirror::DexCache*>(self->DecodeJObject(data.weak_root));
if (dex_cache == nullptr || IsInBootImage(dex_cache)) {
continue;
}
const DexFile* dex_file = dex_cache->GetDexFile();
DexCacheArraysLayout layout(target_ptr_size_, dex_file);
DCHECK(layout.Valid());
size_t oat_index = GetOatIndexForDexCache(dex_cache);
ImageInfo& image_info = GetImageInfo(oat_index);
uint32_t start = image_info.dex_cache_array_starts_.Get(dex_file);
DCHECK_EQ(dex_file->NumTypeIds() != 0u, dex_cache->GetResolvedTypes() != nullptr);
AddDexCacheArrayRelocation(dex_cache->GetResolvedTypes(),
start + layout.TypesOffset(),
dex_cache);
DCHECK_EQ(dex_file->NumMethodIds() != 0u, dex_cache->GetResolvedMethods() != nullptr);
AddDexCacheArrayRelocation(dex_cache->GetResolvedMethods(),
start + layout.MethodsOffset(),
dex_cache);
DCHECK_EQ(dex_file->NumFieldIds() != 0u, dex_cache->GetResolvedFields() != nullptr);
AddDexCacheArrayRelocation(dex_cache->GetResolvedFields(),
start + layout.FieldsOffset(),
dex_cache);
DCHECK_EQ(dex_file->NumStringIds() != 0u, dex_cache->GetStrings() != nullptr);
AddDexCacheArrayRelocation(dex_cache->GetStrings(), start + layout.StringsOffset(), dex_cache);
}
}
void ImageWriter::AddDexCacheArrayRelocation(void* array, size_t offset, DexCache* dex_cache) {
if (array != nullptr) {
DCHECK(!IsInBootImage(array));
size_t oat_index = GetOatIndexForDexCache(dex_cache);
native_object_relocations_.emplace(array,
NativeObjectRelocation { oat_index, offset, kNativeObjectRelocationTypeDexCacheArray });
}
}
void ImageWriter::AddMethodPointerArray(mirror::PointerArray* arr) {
DCHECK(arr != nullptr);
if (kIsDebugBuild) {
for (size_t i = 0, len = arr->GetLength(); i < len; i++) {
ArtMethod* method = arr->GetElementPtrSize<ArtMethod*>(i, target_ptr_size_);
if (method != nullptr && !method->IsRuntimeMethod()) {
mirror::Class* klass = method->GetDeclaringClass();
CHECK(klass == nullptr || KeepClass(klass))
<< PrettyClass(klass) << " should be a kept class";
}
}
}
// kBinArtMethodClean picked arbitrarily, just required to differentiate between ArtFields and
// ArtMethods.
pointer_arrays_.emplace(arr, kBinArtMethodClean);
}
void ImageWriter::AssignImageBinSlot(mirror::Object* object) {
DCHECK(object != nullptr);
size_t object_size = object->SizeOf();
// The magic happens here. We segregate objects into different bins based
// on how likely they are to get dirty at runtime.
//
// Likely-to-dirty objects get packed together into the same bin so that
// at runtime their page dirtiness ratio (how many dirty objects a page has) is
// maximized.
//
// This means more pages will stay either clean or shared dirty (with zygote) and
// the app will use less of its own (private) memory.
Bin bin = kBinRegular;
size_t current_offset = 0u;
if (kBinObjects) {
//
// Changing the bin of an object is purely a memory-use tuning.
// It has no change on runtime correctness.
//
// Memory analysis has determined that the following types of objects get dirtied
// the most:
//
// * Dex cache arrays are stored in a special bin. The arrays for each dex cache have
// a fixed layout which helps improve generated code (using PC-relative addressing),
// so we pre-calculate their offsets separately in PrepareDexCacheArraySlots().
// Since these arrays are huge, most pages do not overlap other objects and it's not
// really important where they are for the clean/dirty separation. Due to their
// special PC-relative addressing, we arbitrarily keep them at the end.
// * Class'es which are verified [their clinit runs only at runtime]
// - classes in general [because their static fields get overwritten]
// - initialized classes with all-final statics are unlikely to be ever dirty,
// so bin them separately
// * Art Methods that are:
// - native [their native entry point is not looked up until runtime]
// - have declaring classes that aren't initialized
// [their interpreter/quick entry points are trampolines until the class
// becomes initialized]
//
// We also assume the following objects get dirtied either never or extremely rarely:
// * Strings (they are immutable)
// * Art methods that aren't native and have initialized declared classes
//
// We assume that "regular" bin objects are highly unlikely to become dirtied,
// so packing them together will not result in a noticeably tighter dirty-to-clean ratio.
//
if (object->IsClass()) {
bin = kBinClassVerified;
mirror::Class* klass = object->AsClass();
// Add non-embedded vtable to the pointer array table if there is one.
auto* vtable = klass->GetVTable();
if (vtable != nullptr) {
AddMethodPointerArray(vtable);
}
auto* iftable = klass->GetIfTable();
if (iftable != nullptr) {
for (int32_t i = 0; i < klass->GetIfTableCount(); ++i) {
if (iftable->GetMethodArrayCount(i) > 0) {
AddMethodPointerArray(iftable->GetMethodArray(i));
}
}
}
if (klass->GetStatus() == Class::kStatusInitialized) {
bin = kBinClassInitialized;
// If the class's static fields are all final, put it into a separate bin
// since it's very likely it will stay clean.
uint32_t num_static_fields = klass->NumStaticFields();
if (num_static_fields == 0) {
bin = kBinClassInitializedFinalStatics;
} else {
// Maybe all the statics are final?
bool all_final = true;
for (uint32_t i = 0; i < num_static_fields; ++i) {
ArtField* field = klass->GetStaticField(i);
if (!field->IsFinal()) {
all_final = false;
break;
}
}
if (all_final) {
bin = kBinClassInitializedFinalStatics;
}
}
}
} else if (object->GetClass<kVerifyNone>()->IsStringClass()) {
bin = kBinString; // Strings are almost always immutable (except for object header).
} // else bin = kBinRegular
}
size_t oat_index = GetOatIndex(object);
ImageInfo& image_info = GetImageInfo(oat_index);
size_t offset_delta = RoundUp(object_size, kObjectAlignment); // 64-bit alignment
current_offset = image_info.bin_slot_sizes_[bin]; // How many bytes the current bin is at (aligned).
// Move the current bin size up to accommodate the object we just assigned a bin slot.
image_info.bin_slot_sizes_[bin] += offset_delta;
BinSlot new_bin_slot(bin, current_offset);
SetImageBinSlot(object, new_bin_slot);
++image_info.bin_slot_count_[bin];
// Grow the image closer to the end by the object we just assigned.
image_info.image_end_ += offset_delta;
}
bool ImageWriter::WillMethodBeDirty(ArtMethod* m) const {
if (m->IsNative()) {
return true;
}
mirror::Class* declaring_class = m->GetDeclaringClass();
// Initialized is highly unlikely to dirty since there's no entry points to mutate.
return declaring_class == nullptr || declaring_class->GetStatus() != Class::kStatusInitialized;
}
bool ImageWriter::IsImageBinSlotAssigned(mirror::Object* object) const {
DCHECK(object != nullptr);
// We always stash the bin slot into a lockword, in the 'forwarding address' state.
// If it's in some other state, then we haven't yet assigned an image bin slot.
if (object->GetLockWord(false).GetState() != LockWord::kForwardingAddress) {
return false;
} else if (kIsDebugBuild) {
LockWord lock_word = object->GetLockWord(false);
size_t offset = lock_word.ForwardingAddress();
BinSlot bin_slot(offset);
size_t oat_index = GetOatIndex(object);
const ImageInfo& image_info = GetImageInfo(oat_index);
DCHECK_LT(bin_slot.GetIndex(), image_info.bin_slot_sizes_[bin_slot.GetBin()])
<< "bin slot offset should not exceed the size of that bin";
}
return true;
}
ImageWriter::BinSlot ImageWriter::GetImageBinSlot(mirror::Object* object) const {
DCHECK(object != nullptr);
DCHECK(IsImageBinSlotAssigned(object));
LockWord lock_word = object->GetLockWord(false);
size_t offset = lock_word.ForwardingAddress(); // TODO: ForwardingAddress should be uint32_t
DCHECK_LE(offset, std::numeric_limits<uint32_t>::max());
BinSlot bin_slot(static_cast<uint32_t>(offset));
size_t oat_index = GetOatIndex(object);
const ImageInfo& image_info = GetImageInfo(oat_index);
DCHECK_LT(bin_slot.GetIndex(), image_info.bin_slot_sizes_[bin_slot.GetBin()]);
return bin_slot;
}
bool ImageWriter::AllocMemory() {
for (ImageInfo& image_info : image_infos_) {
ImageSection unused_sections[ImageHeader::kSectionCount];
const size_t length = RoundUp(
image_info.CreateImageSections(target_ptr_size_, unused_sections),
kPageSize);
std::string error_msg;
image_info.image_.reset(MemMap::MapAnonymous("image writer image",
nullptr,
length,
PROT_READ | PROT_WRITE,
false,
false,
&error_msg));
if (UNLIKELY(image_info.image_.get() == nullptr)) {
LOG(ERROR) << "Failed to allocate memory for image file generation: " << error_msg;
return false;
}
// Create the image bitmap, only needs to cover mirror object section which is up to image_end_.
CHECK_LE(image_info.image_end_, length);
image_info.image_bitmap_.reset(gc::accounting::ContinuousSpaceBitmap::Create(
"image bitmap", image_info.image_->Begin(), RoundUp(image_info.image_end_, kPageSize)));
if (image_info.image_bitmap_.get() == nullptr) {
LOG(ERROR) << "Failed to allocate memory for image bitmap";
return false;
}
}
return true;
}
class ComputeLazyFieldsForClassesVisitor : public ClassVisitor {
public:
bool operator()(Class* c) OVERRIDE SHARED_REQUIRES(Locks::mutator_lock_) {
StackHandleScope<1> hs(Thread::Current());
mirror::Class::ComputeName(hs.NewHandle(c));
return true;
}
};
void ImageWriter::ComputeLazyFieldsForImageClasses() {
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
ComputeLazyFieldsForClassesVisitor visitor;
class_linker->VisitClassesWithoutClassesLock(&visitor);
}
static bool IsBootClassLoaderClass(mirror::Class* klass) SHARED_REQUIRES(Locks::mutator_lock_) {
return klass->GetClassLoader() == nullptr;
}
bool ImageWriter::IsBootClassLoaderNonImageClass(mirror::Class* klass) {
return IsBootClassLoaderClass(klass) && !IsInBootImage(klass);
}
bool ImageWriter::PruneAppImageClass(mirror::Class* klass) {
bool early_exit = false;
std::unordered_set<mirror::Class*> visited;
return PruneAppImageClassInternal(klass, &early_exit, &visited);
}
bool ImageWriter::PruneAppImageClassInternal(
mirror::Class* klass,
bool* early_exit,
std::unordered_set<mirror::Class*>* visited) {
DCHECK(early_exit != nullptr);
DCHECK(visited != nullptr);
DCHECK(compile_app_image_);
if (klass == nullptr || IsInBootImage(klass)) {
return false;
}
auto found = prune_class_memo_.find(klass);
if (found != prune_class_memo_.end()) {
// Already computed, return the found value.
return found->second;
}
// Circular dependencies, return false but do not store the result in the memoization table.
if (visited->find(klass) != visited->end()) {
*early_exit = true;
return false;
}
visited->emplace(klass);
bool result = IsBootClassLoaderClass(klass);
std::string temp;
// Prune if not an image class, this handles any broken sets of image classes such as having a
// class in the set but not it's superclass.
result = result || !compiler_driver_.IsImageClass(klass->GetDescriptor(&temp));
bool my_early_exit = false; // Only for ourselves, ignore caller.
// Remove classes that failed to verify since we don't want to have java.lang.VerifyError in the
// app image.
if (klass->GetStatus() == mirror::Class::kStatusError) {
result = true;
} else {
CHECK(klass->GetVerifyError() == nullptr) << PrettyClass(klass);
}
if (!result) {
// Check interfaces since these wont be visited through VisitReferences.)
mirror::IfTable* if_table = klass->GetIfTable();
for (size_t i = 0, num_interfaces = klass->GetIfTableCount(); i < num_interfaces; ++i) {
result = result || PruneAppImageClassInternal(if_table->GetInterface(i),
&my_early_exit,
visited);
}
}
if (klass->IsObjectArrayClass()) {
result = result || PruneAppImageClassInternal(klass->GetComponentType(),
&my_early_exit,
visited);
}
// Check static fields and their classes.
size_t num_static_fields = klass->NumReferenceStaticFields();
if (num_static_fields != 0 && klass->IsResolved()) {
// Presumably GC can happen when we are cross compiling, it should not cause performance
// problems to do pointer size logic.
MemberOffset field_offset = klass->GetFirstReferenceStaticFieldOffset(
Runtime::Current()->GetClassLinker()->GetImagePointerSize());
for (size_t i = 0u; i < num_static_fields; ++i) {
mirror::Object* ref = klass->GetFieldObject<mirror::Object>(field_offset);
if (ref != nullptr) {
if (ref->IsClass()) {
result = result || PruneAppImageClassInternal(ref->AsClass(),
&my_early_exit,
visited);
} else {
result = result || PruneAppImageClassInternal(ref->GetClass(),
&my_early_exit,
visited);
}
}
field_offset = MemberOffset(field_offset.Uint32Value() +
sizeof(mirror::HeapReference<mirror::Object>));
}
}
result = result || PruneAppImageClassInternal(klass->GetSuperClass(),
&my_early_exit,
visited);
// Erase the element we stored earlier since we are exiting the function.
auto it = visited->find(klass);
DCHECK(it != visited->end());
visited->erase(it);
// Only store result if it is true or none of the calls early exited due to circular
// dependencies. If visited is empty then we are the root caller, in this case the cycle was in
// a child call and we can remember the result.
if (result == true || !my_early_exit || visited->empty()) {
prune_class_memo_[klass] = result;
}
*early_exit |= my_early_exit;
return result;
}
bool ImageWriter::KeepClass(Class* klass) {
if (klass == nullptr) {
return false;
}
if (compile_app_image_ && Runtime::Current()->GetHeap()->ObjectIsInBootImageSpace(klass)) {
// Already in boot image, return true.
return true;
}
std::string temp;
if (!compiler_driver_.IsImageClass(klass->GetDescriptor(&temp))) {
return false;
}
if (compile_app_image_) {
// For app images, we need to prune boot loader classes that are not in the boot image since
// these may have already been loaded when the app image is loaded.
// Keep classes in the boot image space since we don't want to re-resolve these.
return !PruneAppImageClass(klass);
}
return true;
}
class NonImageClassesVisitor : public ClassVisitor {
public:
explicit NonImageClassesVisitor(ImageWriter* image_writer) : image_writer_(image_writer) {}
bool operator()(Class* klass) OVERRIDE SHARED_REQUIRES(Locks::mutator_lock_) {
if (!image_writer_->KeepClass(klass)) {
classes_to_prune_.insert(klass);
}
return true;
}
std::unordered_set<mirror::Class*> classes_to_prune_;
ImageWriter* const image_writer_;
};
void ImageWriter::PruneNonImageClasses() {
Runtime* runtime = Runtime::Current();
ClassLinker* class_linker = runtime->GetClassLinker();
Thread* self = Thread::Current();
// Make a list of classes we would like to prune.
NonImageClassesVisitor visitor(this);
class_linker->VisitClasses(&visitor);
// Remove the undesired classes from the class roots.
VLOG(compiler) << "Pruning " << visitor.classes_to_prune_.size() << " classes";
for (mirror::Class* klass : visitor.classes_to_prune_) {
std::string temp;
const char* name = klass->GetDescriptor(&temp);
VLOG(compiler) << "Pruning class " << name;
if (!compile_app_image_) {
DCHECK(IsBootClassLoaderClass(klass));
}
bool result = class_linker->RemoveClass(name, klass->GetClassLoader());
DCHECK(result);
}
// Clear references to removed classes from the DexCaches.
ArtMethod* resolution_method = runtime->GetResolutionMethod();
ScopedAssertNoThreadSuspension sa(self, __FUNCTION__);
ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_); // For ClassInClassTable
ReaderMutexLock mu2(self, *class_linker->DexLock());
for (const ClassLinker::DexCacheData& data : class_linker->GetDexCachesData()) {
if (self->IsJWeakCleared(data.weak_root)) {
continue;
}
mirror::DexCache* dex_cache = self->DecodeJObject(data.weak_root)->AsDexCache();
for (size_t i = 0; i < dex_cache->NumResolvedTypes(); i++) {
Class* klass = dex_cache->GetResolvedType(i);
if (klass != nullptr && !KeepClass(klass)) {
dex_cache->SetResolvedType(i, nullptr);
}
}
ArtMethod** resolved_methods = dex_cache->GetResolvedMethods();
for (size_t i = 0, num = dex_cache->NumResolvedMethods(); i != num; ++i) {
ArtMethod* method =
mirror::DexCache::GetElementPtrSize(resolved_methods, i, target_ptr_size_);
DCHECK(method != nullptr) << "Expected resolution method instead of null method";
mirror::Class* declaring_class = method->GetDeclaringClass();
// Copied methods may be held live by a class which was not an image class but have a
// declaring class which is an image class. Set it to the resolution method to be safe and
// prevent dangling pointers.
if (method->IsCopied() || !KeepClass(declaring_class)) {
mirror::DexCache::SetElementPtrSize(resolved_methods,
i,
resolution_method,
target_ptr_size_);
} else {
// Check that the class is still in the classes table.
DCHECK(class_linker->ClassInClassTable(declaring_class)) << "Class "
<< PrettyClass(declaring_class) << " not in class linker table";
}
}
ArtField** resolved_fields = dex_cache->GetResolvedFields();
for (size_t i = 0; i < dex_cache->NumResolvedFields(); i++) {
ArtField* field = mirror::DexCache::GetElementPtrSize(resolved_fields, i, target_ptr_size_);
if (field != nullptr && !KeepClass(field->GetDeclaringClass())) {
dex_cache->SetResolvedField(i, nullptr, target_ptr_size_);
}
}
// Clean the dex field. It might have been populated during the initialization phase, but
// contains data only valid during a real run.
dex_cache->SetFieldObject<false>(mirror::DexCache::DexOffset(), nullptr);
}
// Drop the array class cache in the ClassLinker, as these are roots holding those classes live.
class_linker->DropFindArrayClassCache();
// Clear to save RAM.
prune_class_memo_.clear();
}
void ImageWriter::CheckNonImageClassesRemoved() {
if (compiler_driver_.GetImageClasses() != nullptr) {
gc::Heap* heap = Runtime::Current()->GetHeap();
heap->VisitObjects(CheckNonImageClassesRemovedCallback, this);
}
}
void ImageWriter::CheckNonImageClassesRemovedCallback(Object* obj, void* arg) {
ImageWriter* image_writer = reinterpret_cast<ImageWriter*>(arg);
if (obj->IsClass() && !image_writer->IsInBootImage(obj)) {
Class* klass = obj->AsClass();
if (!image_writer->KeepClass(klass)) {
image_writer->DumpImageClasses();
std::string temp;
CHECK(image_writer->KeepClass(klass)) << klass->GetDescriptor(&temp)
<< " " << PrettyDescriptor(klass);
}
}
}
void ImageWriter::DumpImageClasses() {
auto image_classes = compiler_driver_.GetImageClasses();
CHECK(image_classes != nullptr);
for (const std::string& image_class : *image_classes) {
LOG(INFO) << " " << image_class;
}
}
mirror::String* ImageWriter::FindInternedString(mirror::String* string) {
Thread* const self = Thread::Current();
for (const ImageInfo& image_info : image_infos_) {
mirror::String* const found = image_info.intern_table_->LookupStrong(self, string);
DCHECK(image_info.intern_table_->LookupWeak(self, string) == nullptr)
<< string->ToModifiedUtf8();
if (found != nullptr) {
return found;
}
}
if (compile_app_image_) {
Runtime* const runtime = Runtime::Current();
mirror::String* found = runtime->GetInternTable()->LookupStrong(self, string);
// If we found it in the runtime intern table it could either be in the boot image or interned
// during app image compilation. If it was in the boot image return that, otherwise return null
// since it belongs to another image space.
if (found != nullptr && runtime->GetHeap()->ObjectIsInBootImageSpace(found)) {
return found;
}
DCHECK(runtime->GetInternTable()->LookupWeak(self, string) == nullptr)
<< string->ToModifiedUtf8();
}
return nullptr;
}
void ImageWriter::CalculateObjectBinSlots(Object* obj) {
DCHECK(obj != nullptr);
// if it is a string, we want to intern it if its not interned.
if (obj->GetClass()->IsStringClass()) {
size_t oat_index = GetOatIndex(obj);
ImageInfo& image_info = GetImageInfo(oat_index);
// we must be an interned string that was forward referenced and already assigned
if (IsImageBinSlotAssigned(obj)) {
DCHECK_EQ(obj, FindInternedString(obj->AsString()));
return;
}
// Need to check if the string is already interned in another image info so that we don't have
// the intern tables of two different images contain the same string.
mirror::String* interned = FindInternedString(obj->AsString());
if (interned == nullptr) {
// Not in another image space, insert to our table.
interned = image_info.intern_table_->InternStrongImageString(obj->AsString());
}
if (obj != interned) {
if (!IsImageBinSlotAssigned(interned)) {
// interned obj is after us, allocate its location early
AssignImageBinSlot(interned);
}
// point those looking for this object to the interned version.
SetImageBinSlot(obj, GetImageBinSlot(interned));
return;
}
// else (obj == interned), nothing to do but fall through to the normal case
}
AssignImageBinSlot(obj);
}
ObjectArray<Object>* ImageWriter::CreateImageRoots(size_t oat_index) const {
Runtime* runtime = Runtime::Current();
ClassLinker* class_linker = runtime->GetClassLinker();
Thread* self = Thread::Current();
StackHandleScope<3> hs(self);
Handle<Class> object_array_class(hs.NewHandle(
class_linker->FindSystemClass(self, "[Ljava/lang/Object;")));
std::unordered_set<const DexFile*> image_dex_files;
for (auto& pair : dex_file_oat_index_map_) {
const DexFile* image_dex_file = pair.first;
size_t image_oat_index = pair.second;
if (oat_index == image_oat_index) {
image_dex_files.insert(image_dex_file);
}
}
// build an Object[] of all the DexCaches used in the source_space_.
// Since we can't hold the dex lock when allocating the dex_caches
// ObjectArray, we lock the dex lock twice, first to get the number
// of dex caches first and then lock it again to copy the dex
// caches. We check that the number of dex caches does not change.
size_t dex_cache_count = 0;
{
ReaderMutexLock mu(self, *class_linker->DexLock());
// Count number of dex caches not in the boot image.
for (const ClassLinker::DexCacheData& data : class_linker->GetDexCachesData()) {
mirror::DexCache* dex_cache =
down_cast<mirror::DexCache*>(self->DecodeJObject(data.weak_root));
const DexFile* dex_file = dex_cache->GetDexFile();
if (!IsInBootImage(dex_cache)) {
dex_cache_count += image_dex_files.find(dex_file) != image_dex_files.end() ? 1u : 0u;
}
}
}
Handle<ObjectArray<Object>> dex_caches(
hs.NewHandle(ObjectArray<Object>::Alloc(self, object_array_class.Get(), dex_cache_count)));
CHECK(dex_caches.Get() != nullptr) << "Failed to allocate a dex cache array.";
{
ReaderMutexLock mu(self, *class_linker->DexLock());
size_t non_image_dex_caches = 0;
// Re-count number of non image dex caches.
for (const ClassLinker::DexCacheData& data : class_linker->GetDexCachesData()) {
mirror::DexCache* dex_cache =
down_cast<mirror::DexCache*>(self->DecodeJObject(data.weak_root));
const DexFile* dex_file = dex_cache->GetDexFile();
if (!IsInBootImage(dex_cache)) {
non_image_dex_caches += image_dex_files.find(dex_file) != image_dex_files.end() ? 1u : 0u;
}
}
CHECK_EQ(dex_cache_count, non_image_dex_caches)
<< "The number of non-image dex caches changed.";
size_t i = 0;
for (const ClassLinker::DexCacheData& data : class_linker->GetDexCachesData()) {
mirror::DexCache* dex_cache =
down_cast<mirror::DexCache*>(self->DecodeJObject(data.weak_root));
const DexFile* dex_file = dex_cache->GetDexFile();
if (!IsInBootImage(dex_cache) && image_dex_files.find(dex_file) != image_dex_files.end()) {
dex_caches->Set<false>(i, dex_cache);
++i;
}
}
}
// build an Object[] of the roots needed to restore the runtime
auto image_roots(hs.NewHandle(
ObjectArray<Object>::Alloc(self, object_array_class.Get(), ImageHeader::kImageRootsMax)));
image_roots->Set<false>(ImageHeader::kDexCaches, dex_caches.Get());
image_roots->Set<false>(ImageHeader::kClassRoots, class_linker->GetClassRoots());
for (int i = 0; i < ImageHeader::kImageRootsMax; i++) {
CHECK(image_roots->Get(i) != nullptr);
}
return image_roots.Get();
}
// Walk instance fields of the given Class. Separate function to allow recursion on the super
// class.
void ImageWriter::WalkInstanceFields(mirror::Object* obj, mirror::Class* klass) {
// Visit fields of parent classes first.
StackHandleScope<1> hs(Thread::Current());
Handle<mirror::Class> h_class(hs.NewHandle(klass));
mirror::Class* super = h_class->GetSuperClass();
if (super != nullptr) {
WalkInstanceFields(obj, super);
}
//
size_t num_reference_fields = h_class->NumReferenceInstanceFields();
MemberOffset field_offset = h_class->GetFirstReferenceInstanceFieldOffset();
for (size_t i = 0; i < num_reference_fields; ++i) {
mirror::Object* value = obj->GetFieldObject<mirror::Object>(field_offset);
if (value != nullptr) {
WalkFieldsInOrder(value);
}
field_offset = MemberOffset(field_offset.Uint32Value() +
sizeof(mirror::HeapReference<mirror::Object>));
}
}
// For an unvisited object, visit it then all its children found via fields.
void ImageWriter::WalkFieldsInOrder(mirror::Object* obj) {
if (IsInBootImage(obj)) {
// Object is in the image, don't need to fix it up.
return;
}
// Use our own visitor routine (instead of GC visitor) to get better locality between
// an object and its fields
if (!IsImageBinSlotAssigned(obj)) {
// Walk instance fields of all objects
StackHandleScope<2> hs(Thread::Current());
Handle<mirror::Object> h_obj(hs.NewHandle(obj));
Handle<mirror::Class> klass(hs.NewHandle(obj->GetClass()));
// visit the object itself.
CalculateObjectBinSlots(h_obj.Get());
WalkInstanceFields(h_obj.Get(), klass.Get());
// Walk static fields of a Class.
if (h_obj->IsClass()) {
size_t num_reference_static_fields = klass->NumReferenceStaticFields();
MemberOffset field_offset = klass->GetFirstReferenceStaticFieldOffset(target_ptr_size_);
for (size_t i = 0; i < num_reference_static_fields; ++i) {
mirror::Object* value = h_obj->GetFieldObject<mirror::Object>(field_offset);
if (value != nullptr) {
WalkFieldsInOrder(value);
}
field_offset = MemberOffset(field_offset.Uint32Value() +
sizeof(mirror::HeapReference<mirror::Object>));
}
// Visit and assign offsets for fields and field arrays.
auto* as_klass = h_obj->AsClass();
mirror::DexCache* dex_cache = as_klass->GetDexCache();
DCHECK_NE(klass->GetStatus(), mirror::Class::kStatusError);
if (compile_app_image_) {
// Extra sanity, no boot loader classes should be left!
CHECK(!IsBootClassLoaderClass(as_klass)) << PrettyClass(as_klass);
}
LengthPrefixedArray<ArtField>* fields[] = {
as_klass->GetSFieldsPtr(), as_klass->GetIFieldsPtr(),
};
size_t oat_index = GetOatIndexForDexCache(dex_cache);
ImageInfo& image_info = GetImageInfo(oat_index);
{
// Note: This table is only accessed from the image writer, so the lock is technically
// unnecessary.
WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_);
// Insert in the class table for this iamge.
image_info.class_table_->Insert(as_klass);
}
for (LengthPrefixedArray<ArtField>* cur_fields : fields) {
// Total array length including header.
if (cur_fields != nullptr) {
const size_t header_size = LengthPrefixedArray<ArtField>::ComputeSize(0);
// Forward the entire array at once.
auto it = native_object_relocations_.find(cur_fields);
CHECK(it == native_object_relocations_.end()) << "Field array " << cur_fields
<< " already forwarded";
size_t& offset = image_info.bin_slot_sizes_[kBinArtField];
DCHECK(!IsInBootImage(cur_fields));
native_object_relocations_.emplace(
cur_fields,
NativeObjectRelocation {
oat_index, offset, kNativeObjectRelocationTypeArtFieldArray
});
offset += header_size;
// Forward individual fields so that we can quickly find where they belong.
for (size_t i = 0, count = cur_fields->size(); i < count; ++i) {
// Need to forward arrays separate of fields.
ArtField* field = &cur_fields->At(i);
auto it2 = native_object_relocations_.find(field);
CHECK(it2 == native_object_relocations_.end()) << "Field at index=" << i
<< " already assigned " << PrettyField(field) << " static=" << field->IsStatic();
DCHECK(!IsInBootImage(field));
native_object_relocations_.emplace(
field,
NativeObjectRelocation { oat_index, offset, kNativeObjectRelocationTypeArtField });
offset += sizeof(ArtField);
}
}
}
// Visit and assign offsets for methods.
size_t num_methods = as_klass->NumMethods();
if (num_methods != 0) {
bool any_dirty = false;
for (auto& m : as_klass->GetMethods(target_ptr_size_)) {
if (WillMethodBeDirty(&m)) {
any_dirty = true;
break;
}
}
NativeObjectRelocationType type = any_dirty
? kNativeObjectRelocationTypeArtMethodDirty
: kNativeObjectRelocationTypeArtMethodClean;
Bin bin_type = BinTypeForNativeRelocationType(type);
// Forward the entire array at once, but header first.
const size_t method_alignment = ArtMethod::Alignment(target_ptr_size_);
const size_t method_size = ArtMethod::Size(target_ptr_size_);
const size_t header_size = LengthPrefixedArray<ArtMethod>::ComputeSize(0,
method_size,
method_alignment);
LengthPrefixedArray<ArtMethod>* array = as_klass->GetMethodsPtr();
auto it = native_object_relocations_.find(array);
CHECK(it == native_object_relocations_.end())
<< "Method array " << array << " already forwarded";
size_t& offset = image_info.bin_slot_sizes_[bin_type];
DCHECK(!IsInBootImage(array));
native_object_relocations_.emplace(array,
NativeObjectRelocation {
oat_index,
offset,
any_dirty ? kNativeObjectRelocationTypeArtMethodArrayDirty
: kNativeObjectRelocationTypeArtMethodArrayClean });
offset += header_size;
for (auto& m : as_klass->GetMethods(target_ptr_size_)) {
AssignMethodOffset(&m, type, oat_index);
}
(any_dirty ? dirty_methods_ : clean_methods_) += num_methods;
}
} else if (h_obj->IsObjectArray()) {
// Walk elements of an object array.
int32_t length = h_obj->AsObjectArray<mirror::Object>()->GetLength();
for (int32_t i = 0; i < length; i++) {
mirror::ObjectArray<mirror::Object>* obj_array = h_obj->AsObjectArray<mirror::Object>();
mirror::Object* value = obj_array->Get(i);
if (value != nullptr) {
WalkFieldsInOrder(value);
}
}
} else if (h_obj->IsClassLoader()) {
// Register the class loader if it has a class table.
// The fake boot class loader should not get registered and we should end up with only one
// class loader.
mirror::ClassLoader* class_loader = h_obj->AsClassLoader();
if (class_loader->GetClassTable() != nullptr) {
class_loaders_.insert(class_loader);
}
}
}
}
void ImageWriter::AssignMethodOffset(ArtMethod* method,
NativeObjectRelocationType type,
size_t oat_index) {
DCHECK(!IsInBootImage(method));
auto it = native_object_relocations_.find(method);
CHECK(it == native_object_relocations_.end()) << "Method " << method << " already assigned "
<< PrettyMethod(method);
ImageInfo& image_info = GetImageInfo(oat_index);
size_t& offset = image_info.bin_slot_sizes_[BinTypeForNativeRelocationType(type)];
native_object_relocations_.emplace(method, NativeObjectRelocation { oat_index, offset, type });
offset += ArtMethod::Size(target_ptr_size_);
}
void ImageWriter::WalkFieldsCallback(mirror::Object* obj, void* arg) {
ImageWriter* writer = reinterpret_cast<ImageWriter*>(arg);
DCHECK(writer != nullptr);
writer->WalkFieldsInOrder(obj);
}
void ImageWriter::UnbinObjectsIntoOffsetCallback(mirror::Object* obj, void* arg) {
ImageWriter* writer = reinterpret_cast<ImageWriter*>(arg);
DCHECK(writer != nullptr);
if (!writer->IsInBootImage(obj)) {
writer->UnbinObjectsIntoOffset(obj);
}
}
void ImageWriter::UnbinObjectsIntoOffset(mirror::Object* obj) {
DCHECK(!IsInBootImage(obj));
CHECK(obj != nullptr);
// We know the bin slot, and the total bin sizes for all objects by now,
// so calculate the object's final image offset.
DCHECK(IsImageBinSlotAssigned(obj));
BinSlot bin_slot = GetImageBinSlot(obj);
// Change the lockword from a bin slot into an offset
AssignImageOffset(obj, bin_slot);
}
void ImageWriter::CalculateNewObjectOffsets() {
Thread* const self = Thread::Current();
StackHandleScopeCollection handles(self);
std::vector<Handle<ObjectArray<Object>>> image_roots;
for (size_t i = 0, size = oat_filenames_.size(); i != size; ++i) {
image_roots.push_back(handles.NewHandle(CreateImageRoots(i)));
}
auto* runtime = Runtime::Current();
auto* heap = runtime->GetHeap();
// Leave space for the header, but do not write it yet, we need to
// know where image_roots is going to end up
image_objects_offset_begin_ = RoundUp(sizeof(ImageHeader), kObjectAlignment); // 64-bit-alignment
// Clear any pre-existing monitors which may have been in the monitor words, assign bin slots.
heap->VisitObjects(WalkFieldsCallback, this);
// Write the image runtime methods.
image_methods_[ImageHeader::kResolutionMethod] = runtime->GetResolutionMethod();
image_methods_[ImageHeader::kImtConflictMethod] = runtime->GetImtConflictMethod();
image_methods_[ImageHeader::kImtUnimplementedMethod] = runtime->GetImtUnimplementedMethod();
image_methods_[ImageHeader::kCalleeSaveMethod] = runtime->GetCalleeSaveMethod(Runtime::kSaveAll);
image_methods_[ImageHeader::kRefsOnlySaveMethod] =
runtime->GetCalleeSaveMethod(Runtime::kRefsOnly);
image_methods_[ImageHeader::kRefsAndArgsSaveMethod] =
runtime->GetCalleeSaveMethod(Runtime::kRefsAndArgs);
// Add room for fake length prefixed array for holding the image methods.
const auto image_method_type = kNativeObjectRelocationTypeArtMethodArrayClean;
auto it = native_object_relocations_.find(&image_method_array_);
CHECK(it == native_object_relocations_.end());
ImageInfo& default_image_info = GetImageInfo(GetDefaultOatIndex());
size_t& offset =
default_image_info.bin_slot_sizes_[BinTypeForNativeRelocationType(image_method_type)];
if (!compile_app_image_) {
native_object_relocations_.emplace(&image_method_array_,
NativeObjectRelocation { GetDefaultOatIndex(), offset, image_method_type });
}
size_t method_alignment = ArtMethod::Alignment(target_ptr_size_);
const size_t array_size = LengthPrefixedArray<ArtMethod>::ComputeSize(
0, ArtMethod::Size(target_ptr_size_), method_alignment);
CHECK_ALIGNED_PARAM(array_size, method_alignment);
offset += array_size;
for (auto* m : image_methods_) {
CHECK(m != nullptr);
CHECK(m->IsRuntimeMethod());
DCHECK_EQ(compile_app_image_, IsInBootImage(m)) << "Trampolines should be in boot image";
if (!IsInBootImage(m)) {
AssignMethodOffset(m, kNativeObjectRelocationTypeArtMethodClean, GetDefaultOatIndex());
}
}
// Calculate size of the dex cache arrays slot and prepare offsets.
PrepareDexCacheArraySlots();
// Calculate the sizes of the intern tables and class tables.
for (ImageInfo& image_info : image_infos_) {
// Calculate how big the intern table will be after being serialized.
InternTable* const intern_table = image_info.intern_table_.get();
CHECK_EQ(intern_table->WeakSize(), 0u) << " should have strong interned all the strings";
image_info.intern_table_bytes_ = intern_table->WriteToMemory(nullptr);
// Calculate the size of the class table.
ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_);
image_info.class_table_bytes_ += image_info.class_table_->WriteToMemory(nullptr);
}
// Calculate bin slot offsets.
for (ImageInfo& image_info : image_infos_) {
size_t bin_offset = image_objects_offset_begin_;
for (size_t i = 0; i != kBinSize; ++i) {
image_info.bin_slot_offsets_[i] = bin_offset;
bin_offset += image_info.bin_slot_sizes_[i];
if (i == kBinArtField) {
static_assert(kBinArtField + 1 == kBinArtMethodClean, "Methods follow fields.");
static_assert(alignof(ArtField) == 4u, "ArtField alignment is 4.");
DCHECK_ALIGNED(bin_offset, 4u);
DCHECK(method_alignment == 4u || method_alignment == 8u);
bin_offset = RoundUp(bin_offset, method_alignment);
}
}
// NOTE: There may be additional padding between the bin slots and the intern table.
DCHECK_EQ(image_info.image_end_,
GetBinSizeSum(image_info, kBinMirrorCount) + image_objects_offset_begin_);
}
// Calculate image offsets.
size_t image_offset = 0;
for (ImageInfo& image_info : image_infos_) {
image_info.image_begin_ = global_image_begin_ + image_offset;
image_info.image_offset_ = image_offset;
ImageSection unused_sections[ImageHeader::kSectionCount];
image_info.image_size_ = RoundUp(
image_info.CreateImageSections(target_ptr_size_, unused_sections),
kPageSize);
// There should be no gaps until the next image.
image_offset += image_info.image_size_;
}
// Transform each object's bin slot into an offset which will be used to do the final copy.
heap->VisitObjects(UnbinObjectsIntoOffsetCallback, this);
// DCHECK_EQ(image_end_, GetBinSizeSum(kBinMirrorCount) + image_objects_offset_begin_);
size_t i = 0;
for (ImageInfo& image_info : image_infos_) {
image_info.image_roots_address_ = PointerToLowMemUInt32(GetImageAddress(image_roots[i].Get()));
i++;
}
// Update the native relocations by adding their bin sums.
for (auto& pair : native_object_relocations_) {
NativeObjectRelocation& relocation = pair.second;
Bin bin_type = BinTypeForNativeRelocationType(relocation.type);
ImageInfo& image_info = GetImageInfo(relocation.oat_index);
relocation.offset += image_info.bin_slot_offsets_[bin_type];
}
// Note that image_info.image_end_ is left at end of used mirror object section.
}
size_t ImageWriter::ImageInfo::CreateImageSections(size_t target_ptr_size,
ImageSection* out_sections) const {
DCHECK(out_sections != nullptr);
// Objects section
auto* objects_section = &out_sections[ImageHeader::kSectionObjects];
*objects_section = ImageSection(0u, image_end_);
size_t cur_pos = objects_section->End();
// Add field section.
auto* field_section = &out_sections[ImageHeader::kSectionArtFields];
*field_section = ImageSection(cur_pos, bin_slot_sizes_[kBinArtField]);
CHECK_EQ(bin_slot_offsets_[kBinArtField], field_section->Offset());
cur_pos = field_section->End();
// Round up to the alignment the required by the method section.
cur_pos = RoundUp(cur_pos, ArtMethod::Alignment(target_ptr_size));
// Add method section.
auto* methods_section = &out_sections[ImageHeader::kSectionArtMethods];
*methods_section = ImageSection(cur_pos,
bin_slot_sizes_[kBinArtMethodClean] +
bin_slot_sizes_[kBinArtMethodDirty]);
CHECK_EQ(bin_slot_offsets_[kBinArtMethodClean], methods_section->Offset());
cur_pos = methods_section->End();
// Add dex cache arrays section.
auto* dex_cache_arrays_section = &out_sections[ImageHeader::kSectionDexCacheArrays];
*dex_cache_arrays_section = ImageSection(cur_pos, bin_slot_sizes_[kBinDexCacheArray]);
CHECK_EQ(bin_slot_offsets_[kBinDexCacheArray], dex_cache_arrays_section->Offset());
cur_pos = dex_cache_arrays_section->End();
// Round up to the alignment the string table expects. See HashSet::WriteToMemory.
cur_pos = RoundUp(cur_pos, sizeof(uint64_t));
// Calculate the size of the interned strings.
auto* interned_strings_section = &out_sections[ImageHeader::kSectionInternedStrings];
*interned_strings_section = ImageSection(cur_pos, intern_table_bytes_);
cur_pos = interned_strings_section->End();
// Round up to the alignment the class table expects. See HashSet::WriteToMemory.
cur_pos = RoundUp(cur_pos, sizeof(uint64_t));
// Calculate the size of the class table section.
auto* class_table_section = &out_sections[ImageHeader::kSectionClassTable];
*class_table_section = ImageSection(cur_pos, class_table_bytes_);
cur_pos = class_table_section->End();
// Image end goes right before the start of the image bitmap.
return cur_pos;
}
void ImageWriter::CreateHeader(size_t oat_index) {
ImageInfo& image_info = GetImageInfo(oat_index);
const uint8_t* oat_file_begin = image_info.oat_file_begin_;
const uint8_t* oat_file_end = oat_file_begin + image_info.oat_loaded_size_;
const uint8_t* oat_data_end = image_info.oat_data_begin_ + image_info.oat_size_;
// Create the image sections.
ImageSection sections[ImageHeader::kSectionCount];
const size_t image_end = image_info.CreateImageSections(target_ptr_size_, sections);
// Finally bitmap section.
const size_t bitmap_bytes = image_info.image_bitmap_->Size();
auto* bitmap_section = &sections[ImageHeader::kSectionImageBitmap];
*bitmap_section = ImageSection(RoundUp(image_end, kPageSize), RoundUp(bitmap_bytes, kPageSize));
if (VLOG_IS_ON(compiler)) {
LOG(INFO) << "Creating header for " << oat_filenames_[oat_index];
size_t idx = 0;
for (const ImageSection& section : sections) {
LOG(INFO) << static_cast<ImageHeader::ImageSections>(idx) << " " << section;
++idx;
}
LOG(INFO) << "Methods: clean=" << clean_methods_ << " dirty=" << dirty_methods_;
LOG(INFO) << "Image roots address=" << std::hex << image_info.image_roots_address_ << std::dec;
LOG(INFO) << "Image begin=" << std::hex << reinterpret_cast<uintptr_t>(global_image_begin_)
<< " Image offset=" << image_info.image_offset_ << std::dec;
LOG(INFO) << "Oat file begin=" << std::hex << reinterpret_cast<uintptr_t>(oat_file_begin)
<< " Oat data begin=" << reinterpret_cast<uintptr_t>(image_info.oat_data_begin_)
<< " Oat data end=" << reinterpret_cast<uintptr_t>(oat_data_end)
<< " Oat file end=" << reinterpret_cast<uintptr_t>(oat_file_end);
}
// Store boot image info for app image so that we can relocate.
uint32_t boot_image_begin = 0;
uint32_t boot_image_end = 0;
uint32_t boot_oat_begin = 0;
uint32_t boot_oat_end = 0;
gc::Heap* const heap = Runtime::Current()->GetHeap();
heap->GetBootImagesSize(&boot_image_begin, &boot_image_end, &boot_oat_begin, &boot_oat_end);
// Create the header, leave 0 for data size since we will fill this in as we are writing the
// image.
new (image_info.image_->Begin()) ImageHeader(PointerToLowMemUInt32(image_info.image_begin_),
image_end,
sections,
image_info.image_roots_address_,
image_info.oat_checksum_,
PointerToLowMemUInt32(oat_file_begin),
PointerToLowMemUInt32(image_info.oat_data_begin_),
PointerToLowMemUInt32(oat_data_end),
PointerToLowMemUInt32(oat_file_end),
boot_image_begin,
boot_image_end - boot_image_begin,
boot_oat_begin,
boot_oat_end - boot_oat_begin,
target_ptr_size_,
compile_pic_,
/*is_pic*/compile_app_image_,
image_storage_mode_,
/*data_size*/0u);
}
ArtMethod* ImageWriter::GetImageMethodAddress(ArtMethod* method) {
auto it = native_object_relocations_.find(method);
CHECK(it != native_object_relocations_.end()) << PrettyMethod(method) << " @ " << method;
size_t oat_index = GetOatIndex(method->GetDexCache());
ImageInfo& image_info = GetImageInfo(oat_index);
CHECK_GE(it->second.offset, image_info.image_end_) << "ArtMethods should be after Objects";
return reinterpret_cast<ArtMethod*>(image_info.image_begin_ + it->second.offset);
}
class FixupRootVisitor : public RootVisitor {
public:
explicit FixupRootVisitor(ImageWriter* image_writer) : image_writer_(image_writer) {
}
void VisitRoots(mirror::Object*** roots, size_t count, const RootInfo& info ATTRIBUTE_UNUSED)
OVERRIDE SHARED_REQUIRES(Locks::mutator_lock_) {
for (size_t i = 0; i < count; ++i) {
*roots[i] = image_writer_->GetImageAddress(*roots[i]);
}
}
void VisitRoots(mirror::CompressedReference<mirror::Object>** roots, size_t count,
const RootInfo& info ATTRIBUTE_UNUSED)
OVERRIDE SHARED_REQUIRES(Locks::mutator_lock_) {
for (size_t i = 0; i < count; ++i) {
roots[i]->Assign(image_writer_->GetImageAddress(roots[i]->AsMirrorPtr()));
}
}
private:
ImageWriter* const image_writer_;
};
void ImageWriter::CopyAndFixupNativeData(size_t oat_index) {
ImageInfo& image_info = GetImageInfo(oat_index);
// Copy ArtFields and methods to their locations and update the array for convenience.
for (auto& pair : native_object_relocations_) {
NativeObjectRelocation& relocation = pair.second;
// Only work with fields and methods that are in the current oat file.
if (relocation.oat_index != oat_index) {
continue;
}
auto* dest = image_info.image_->Begin() + relocation.offset;
DCHECK_GE(dest, image_info.image_->Begin() + image_info.image_end_);
DCHECK(!IsInBootImage(pair.first));
switch (relocation.type) {
case kNativeObjectRelocationTypeArtField: {
memcpy(dest, pair.first, sizeof(ArtField));
reinterpret_cast<ArtField*>(dest)->SetDeclaringClass(
GetImageAddress(reinterpret_cast<ArtField*>(pair.first)->GetDeclaringClass()));
break;
}
case kNativeObjectRelocationTypeArtMethodClean:
case kNativeObjectRelocationTypeArtMethodDirty: {
CopyAndFixupMethod(reinterpret_cast<ArtMethod*>(pair.first),
reinterpret_cast<ArtMethod*>(dest),
image_info);
break;
}
// For arrays, copy just the header since the elements will get copied by their corresponding
// relocations.
case kNativeObjectRelocationTypeArtFieldArray: {
memcpy(dest, pair.first, LengthPrefixedArray<ArtField>::ComputeSize(0));
break;
}
case kNativeObjectRelocationTypeArtMethodArrayClean:
case kNativeObjectRelocationTypeArtMethodArrayDirty: {
size_t size = ArtMethod::Size(target_ptr_size_);
size_t alignment = ArtMethod::Alignment(target_ptr_size_);
memcpy(dest, pair.first, LengthPrefixedArray<ArtMethod>::ComputeSize(0, size, alignment));
// Clear padding to avoid non-deterministic data in the image (and placate valgrind).
reinterpret_cast<LengthPrefixedArray<ArtMethod>*>(dest)->ClearPadding(size, alignment);
break;
}
case kNativeObjectRelocationTypeDexCacheArray:
// Nothing to copy here, everything is done in FixupDexCache().
break;
}
}
// Fixup the image method roots.
auto* image_header = reinterpret_cast<ImageHeader*>(image_info.image_->Begin());
const ImageSection& methods_section = image_header->GetMethodsSection();
for (size_t i = 0; i < ImageHeader::kImageMethodsCount; ++i) {
ArtMethod* method = image_methods_[i];
CHECK(method != nullptr);
// Only place runtime methods in the image of the default oat file.
if (method->IsRuntimeMethod() && oat_index != GetDefaultOatIndex()) {
continue;
}
if (!IsInBootImage(method)) {
auto it = native_object_relocations_.find(method);
CHECK(it != native_object_relocations_.end()) << "No forwarding for " << PrettyMethod(method);
NativeObjectRelocation& relocation = it->second;
CHECK(methods_section.Contains(relocation.offset)) << relocation.offset << " not in "
<< methods_section;
CHECK(relocation.IsArtMethodRelocation()) << relocation.type;
method = reinterpret_cast<ArtMethod*>(global_image_begin_ + it->second.offset);
}
image_header->SetImageMethod(static_cast<ImageHeader::ImageMethod>(i), method);
}
FixupRootVisitor root_visitor(this);
// Write the intern table into the image.
if (image_info.intern_table_bytes_ > 0) {
const ImageSection& intern_table_section = image_header->GetImageSection(
ImageHeader::kSectionInternedStrings);
InternTable* const intern_table = image_info.intern_table_.get();
uint8_t* const intern_table_memory_ptr =
image_info.image_->Begin() + intern_table_section.Offset();
const size_t intern_table_bytes = intern_table->WriteToMemory(intern_table_memory_ptr);
CHECK_EQ(intern_table_bytes, image_info.intern_table_bytes_);
// Fixup the pointers in the newly written intern table to contain image addresses.
InternTable temp_intern_table;
// Note that we require that ReadFromMemory does not make an internal copy of the elements so that
// the VisitRoots() will update the memory directly rather than the copies.
// This also relies on visit roots not doing any verification which could fail after we update
// the roots to be the image addresses.
temp_intern_table.AddTableFromMemory(intern_table_memory_ptr);
CHECK_EQ(temp_intern_table.Size(), intern_table->Size());
temp_intern_table.VisitRoots(&root_visitor, kVisitRootFlagAllRoots);
}
// Write the class table(s) into the image. class_table_bytes_ may be 0 if there are multiple
// class loaders. Writing multiple class tables into the image is currently unsupported.
if (image_info.class_table_bytes_ > 0u) {
const ImageSection& class_table_section = image_header->GetImageSection(
ImageHeader::kSectionClassTable);
uint8_t* const class_table_memory_ptr =
image_info.image_->Begin() + class_table_section.Offset();
ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_);
ClassTable* table = image_info.class_table_.get();
CHECK(table != nullptr);
const size_t class_table_bytes = table->WriteToMemory(class_table_memory_ptr);
CHECK_EQ(class_table_bytes, image_info.class_table_bytes_);
// Fixup the pointers in the newly written class table to contain image addresses. See
// above comment for intern tables.
ClassTable temp_class_table;
temp_class_table.ReadFromMemory(class_table_memory_ptr);
CHECK_EQ(temp_class_table.NumZygoteClasses(), table->NumNonZygoteClasses() +
table->NumZygoteClasses());
BufferedRootVisitor<kDefaultBufferedRootCount> buffered_visitor(&root_visitor,
RootInfo(kRootUnknown));
temp_class_table.VisitRoots(buffered_visitor);
}
}
void ImageWriter::CopyAndFixupObjects() {
gc::Heap* heap = Runtime::Current()->GetHeap();
heap->VisitObjects(CopyAndFixupObjectsCallback, this);
// Fix up the object previously had hash codes.
for (const auto& hash_pair : saved_hashcode_map_) {
Object* obj = hash_pair.first;
DCHECK_EQ(obj->GetLockWord<kVerifyNone>(false).ReadBarrierState(), 0U);
obj->SetLockWord<kVerifyNone>(LockWord::FromHashCode(hash_pair.second, 0U), false);
}
saved_hashcode_map_.clear();
}
void ImageWriter::CopyAndFixupObjectsCallback(Object* obj, void* arg) {
DCHECK(obj != nullptr);
DCHECK(arg != nullptr);
reinterpret_cast<ImageWriter*>(arg)->CopyAndFixupObject(obj);
}
void ImageWriter::FixupPointerArray(mirror::Object* dst, mirror::PointerArray* arr,
mirror::Class* klass, Bin array_type) {
CHECK(klass->IsArrayClass());
CHECK(arr->IsIntArray() || arr->IsLongArray()) << PrettyClass(klass) << " " << arr;
// Fixup int and long pointers for the ArtMethod or ArtField arrays.
const size_t num_elements = arr->GetLength();
dst->SetClass(GetImageAddress(arr->GetClass()));
auto* dest_array = down_cast<mirror::PointerArray*>(dst);
for (size_t i = 0, count = num_elements; i < count; ++i) {
void* elem = arr->GetElementPtrSize<void*>(i, target_ptr_size_);
if (elem != nullptr && !IsInBootImage(elem)) {
auto it = native_object_relocations_.find(elem);
if (UNLIKELY(it == native_object_relocations_.end())) {
if (it->second.IsArtMethodRelocation()) {
auto* method = reinterpret_cast<ArtMethod*>(elem);
LOG(FATAL) << "No relocation entry for ArtMethod " << PrettyMethod(method) << " @ "
<< method << " idx=" << i << "/" << num_elements << " with declaring class "
<< PrettyClass(method->GetDeclaringClass());
} else {
CHECK_EQ(array_type, kBinArtField);
auto* field = reinterpret_cast<ArtField*>(elem);
LOG(FATAL) << "No relocation entry for ArtField " << PrettyField(field) << " @ "
<< field << " idx=" << i << "/" << num_elements << " with declaring class "
<< PrettyClass(field->GetDeclaringClass());
}
UNREACHABLE();
} else {
ImageInfo& image_info = GetImageInfo(it->second.oat_index);
elem = image_info.image_begin_ + it->second.offset;
}
}
dest_array->SetElementPtrSize<false, true>(i, elem, target_ptr_size_);
}
}
void ImageWriter::CopyAndFixupObject(Object* obj) {
if (IsInBootImage(obj)) {
return;
}
size_t offset = GetImageOffset(obj);
size_t oat_index = GetOatIndex(obj);
ImageInfo& image_info = GetImageInfo(oat_index);
auto* dst = reinterpret_cast<Object*>(image_info.image_->Begin() + offset);
DCHECK_LT(offset, image_info.image_end_);
const auto* src = reinterpret_cast<const uint8_t*>(obj);
image_info.image_bitmap_->Set(dst); // Mark the obj as live.
const size_t n = obj->SizeOf();
DCHECK_LE(offset + n, image_info.image_->Size());
memcpy(dst, src, n);
// Write in a hash code of objects which have inflated monitors or a hash code in their monitor
// word.
const auto it = saved_hashcode_map_.find(obj);
dst->SetLockWord(it != saved_hashcode_map_.end() ?
LockWord::FromHashCode(it->second, 0u) : LockWord::Default(), false);
FixupObject(obj, dst);
}
// Rewrite all the references in the copied object to point to their image address equivalent
class FixupVisitor {
public:
FixupVisitor(ImageWriter* image_writer, Object* copy) : image_writer_(image_writer), copy_(copy) {
}
// Ignore class roots since we don't have a way to map them to the destination. These are handled
// with other logic.
void VisitRootIfNonNull(mirror::CompressedReference<mirror::Object>* root ATTRIBUTE_UNUSED)
const {}
void VisitRoot(mirror::CompressedReference<mirror::Object>* root ATTRIBUTE_UNUSED) const {}
void operator()(Object* obj, MemberOffset offset, bool is_static ATTRIBUTE_UNUSED) const
REQUIRES(Locks::mutator_lock_, Locks::heap_bitmap_lock_) {
Object* ref = obj->GetFieldObject<Object, kVerifyNone>(offset);
// Use SetFieldObjectWithoutWriteBarrier to avoid card marking since we are writing to the
// image.
copy_->SetFieldObjectWithoutWriteBarrier<false, true, kVerifyNone>(
offset,
image_writer_->GetImageAddress(ref));
}
// java.lang.ref.Reference visitor.
void operator()(mirror::Class* klass ATTRIBUTE_UNUSED, mirror::Reference* ref) const
SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(Locks::heap_bitmap_lock_) {
copy_->SetFieldObjectWithoutWriteBarrier<false, true, kVerifyNone>(
mirror::Reference::ReferentOffset(),
image_writer_->GetImageAddress(ref->GetReferent()));
}
protected:
ImageWriter* const image_writer_;
mirror::Object* const copy_;
};
class FixupClassVisitor FINAL : public FixupVisitor {
public:
FixupClassVisitor(ImageWriter* image_writer, Object* copy) : FixupVisitor(image_writer, copy) {
}
void operator()(Object* obj, MemberOffset offset, bool is_static ATTRIBUTE_UNUSED) const
REQUIRES(Locks::mutator_lock_, Locks::heap_bitmap_lock_) {
DCHECK(obj->IsClass());
FixupVisitor::operator()(obj, offset, /*is_static*/false);
}
void operator()(mirror::Class* klass ATTRIBUTE_UNUSED,
mirror::Reference* ref ATTRIBUTE_UNUSED) const
SHARED_REQUIRES(Locks::mutator_lock_) REQUIRES(Locks::heap_bitmap_lock_) {
LOG(FATAL) << "Reference not expected here.";
}
};
uintptr_t ImageWriter::NativeOffsetInImage(void* obj) {
DCHECK(obj != nullptr);
DCHECK(!IsInBootImage(obj));
auto it = native_object_relocations_.find(obj);
CHECK(it != native_object_relocations_.end()) << obj << " spaces "
<< Runtime::Current()->GetHeap()->DumpSpaces();
const NativeObjectRelocation& relocation = it->second;
return relocation.offset;
}
template <typename T>
T* ImageWriter::NativeLocationInImage(T* obj) {
if (obj == nullptr || IsInBootImage(obj)) {
return obj;
} else {
auto it = native_object_relocations_.find(obj);
CHECK(it != native_object_relocations_.end()) << obj << " spaces "
<< Runtime::Current()->GetHeap()->DumpSpaces();
const NativeObjectRelocation& relocation = it->second;
ImageInfo& image_info = GetImageInfo(relocation.oat_index);
return reinterpret_cast<T*>(image_info.image_begin_ + relocation.offset);
}
}
template <typename T>
T* ImageWriter::NativeCopyLocation(T* obj, mirror::DexCache* dex_cache) {
if (obj == nullptr || IsInBootImage(obj)) {
return obj;
} else {
size_t oat_index = GetOatIndexForDexCache(dex_cache);
ImageInfo& image_info = GetImageInfo(oat_index);
return reinterpret_cast<T*>(image_info.image_->Begin() + NativeOffsetInImage(obj));
}
}
class NativeLocationVisitor {
public:
explicit NativeLocationVisitor(ImageWriter* image_writer) : image_writer_(image_writer) {}
template <typename T>
T* operator()(T* ptr) const SHARED_REQUIRES(Locks::mutator_lock_) {
return image_writer_->NativeLocationInImage(ptr);
}
private:
ImageWriter* const image_writer_;
};
void ImageWriter::FixupClass(mirror::Class* orig, mirror::Class* copy) {
orig->FixupNativePointers(copy, target_ptr_size_, NativeLocationVisitor(this));
FixupClassVisitor visitor(this, copy);
static_cast<mirror::Object*>(orig)->VisitReferences(visitor, visitor);
// Remove the clinitThreadId. This is required for image determinism.
copy->SetClinitThreadId(static_cast<pid_t>(0));
}
void ImageWriter::FixupObject(Object* orig, Object* copy) {
DCHECK(orig != nullptr);
DCHECK(copy != nullptr);
if (kUseBakerOrBrooksReadBarrier) {
orig->AssertReadBarrierPointer();
if (kUseBrooksReadBarrier) {
// Note the address 'copy' isn't the same as the image address of 'orig'.
copy->SetReadBarrierPointer(GetImageAddress(orig));
DCHECK_EQ(copy->GetReadBarrierPointer(), GetImageAddress(orig));
}
}
auto* klass = orig->GetClass();
if (klass->IsIntArrayClass() || klass->IsLongArrayClass()) {
// Is this a native pointer array?
auto it = pointer_arrays_.find(down_cast<mirror::PointerArray*>(orig));
if (it != pointer_arrays_.end()) {
// Should only need to fixup every pointer array exactly once.
FixupPointerArray(copy, down_cast<mirror::PointerArray*>(orig), klass, it->second);
pointer_arrays_.erase(it);
return;
}
}
if (orig->IsClass()) {
FixupClass(orig->AsClass<kVerifyNone>(), down_cast<mirror::Class*>(copy));
} else {
if (klass == mirror::Method::StaticClass() || klass == mirror::Constructor::StaticClass()) {
// Need to go update the ArtMethod.
auto* dest = down_cast<mirror::AbstractMethod*>(copy);
auto* src = down_cast<mirror::AbstractMethod*>(orig);
ArtMethod* src_method = src->GetArtMethod();
auto it = native_object_relocations_.find(src_method);
CHECK(it != native_object_relocations_.end())
<< "Missing relocation for AbstractMethod.artMethod " << PrettyMethod(src_method);
dest->SetArtMethod(
reinterpret_cast<ArtMethod*>(global_image_begin_ + it->second.offset));
} else if (!klass->IsArrayClass()) {
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
if (klass == class_linker->GetClassRoot(ClassLinker::kJavaLangDexCache)) {
FixupDexCache(down_cast<mirror::DexCache*>(orig), down_cast<mirror::DexCache*>(copy));
} else if (klass->IsClassLoaderClass()) {
mirror::ClassLoader* copy_loader = down_cast<mirror::ClassLoader*>(copy);
// If src is a ClassLoader, set the class table to null so that it gets recreated by the
// ClassLoader.
copy_loader->SetClassTable(nullptr);
// Also set allocator to null to be safe. The allocator is created when we create the class
// table. We also never expect to unload things in the image since they are held live as
// roots.
copy_loader->SetAllocator(nullptr);
}
}
FixupVisitor visitor(this, copy);
orig->VisitReferences(visitor, visitor);
}
}
class ImageAddressVisitor {
public:
explicit ImageAddressVisitor(ImageWriter* image_writer) : image_writer_(image_writer) {}
template <typename T>
T* operator()(T* ptr) const SHARED_REQUIRES(Locks::mutator_lock_) {
return image_writer_->GetImageAddress(ptr);
}
private:
ImageWriter* const image_writer_;
};
void ImageWriter::FixupDexCache(mirror::DexCache* orig_dex_cache,
mirror::DexCache* copy_dex_cache) {
// Though the DexCache array fields are usually treated as native pointers, we set the full
// 64-bit values here, clearing the top 32 bits for 32-bit targets. The zero-extension is
// done by casting to the unsigned type uintptr_t before casting to int64_t, i.e.
// static_cast<int64_t>(reinterpret_cast<uintptr_t>(image_begin_ + offset))).
GcRoot<mirror::String>* orig_strings = orig_dex_cache->GetStrings();
if (orig_strings != nullptr) {
copy_dex_cache->SetFieldPtrWithSize<false>(mirror::DexCache::StringsOffset(),
NativeLocationInImage(orig_strings),
/*pointer size*/8u);
orig_dex_cache->FixupStrings(NativeCopyLocation(orig_strings, orig_dex_cache),
ImageAddressVisitor(this));
}
GcRoot<mirror::Class>* orig_types = orig_dex_cache->GetResolvedTypes();
if (orig_types != nullptr) {
copy_dex_cache->SetFieldPtrWithSize<false>(mirror::DexCache::ResolvedTypesOffset(),
NativeLocationInImage(orig_types),
/*pointer size*/8u);
orig_dex_cache->FixupResolvedTypes(NativeCopyLocation(orig_types, orig_dex_cache),
ImageAddressVisitor(this));
}
ArtMethod** orig_methods = orig_dex_cache->GetResolvedMethods();
if (orig_methods != nullptr) {
copy_dex_cache->SetFieldPtrWithSize<false>(mirror::DexCache::ResolvedMethodsOffset(),
NativeLocationInImage(orig_methods),
/*pointer size*/8u);
ArtMethod** copy_methods = NativeCopyLocation(orig_methods, orig_dex_cache);
for (size_t i = 0, num = orig_dex_cache->NumResolvedMethods(); i != num; ++i) {
ArtMethod* orig = mirror::DexCache::GetElementPtrSize(orig_methods, i, target_ptr_size_);
// NativeLocationInImage also handles runtime methods since these have relocation info.
ArtMethod* copy = NativeLocationInImage(orig);
mirror::DexCache::SetElementPtrSize(copy_methods, i, copy, target_ptr_size_);
}
}
ArtField** orig_fields = orig_dex_cache->GetResolvedFields();
if (orig_fields != nullptr) {
copy_dex_cache->SetFieldPtrWithSize<false>(mirror::DexCache::ResolvedFieldsOffset(),
NativeLocationInImage(orig_fields),
/*pointer size*/8u);
ArtField** copy_fields = NativeCopyLocation(orig_fields, orig_dex_cache);
for (size_t i = 0, num = orig_dex_cache->NumResolvedFields(); i != num; ++i) {
ArtField* orig = mirror::DexCache::GetElementPtrSize(orig_fields, i, target_ptr_size_);
ArtField* copy = NativeLocationInImage(orig);
mirror::DexCache::SetElementPtrSize(copy_fields, i, copy, target_ptr_size_);
}
}
// Remove the DexFile pointers. They will be fixed up when the runtime loads the oat file. Leaving
// compiler pointers in here will make the output non-deterministic.
copy_dex_cache->SetDexFile(nullptr);
}
const uint8_t* ImageWriter::GetOatAddress(OatAddress type) const {
DCHECK_LT(type, kOatAddressCount);
// If we are compiling an app image, we need to use the stubs of the boot image.
if (compile_app_image_) {
// Use the current image pointers.
const std::vector<gc::space::ImageSpace*>& image_spaces =
Runtime::Current()->GetHeap()->GetBootImageSpaces();
DCHECK(!image_spaces.empty());
const OatFile* oat_file = image_spaces[0]->GetOatFile();
CHECK(oat_file != nullptr);
const OatHeader& header = oat_file->GetOatHeader();
switch (type) {
// TODO: We could maybe clean this up if we stored them in an array in the oat header.
case kOatAddressQuickGenericJNITrampoline:
return static_cast<const uint8_t*>(header.GetQuickGenericJniTrampoline());
case kOatAddressInterpreterToInterpreterBridge:
return static_cast<const uint8_t*>(header.GetInterpreterToInterpreterBridge());
case kOatAddressInterpreterToCompiledCodeBridge:
return static_cast<const uint8_t*>(header.GetInterpreterToCompiledCodeBridge());
case kOatAddressJNIDlsymLookup:
return static_cast<const uint8_t*>(header.GetJniDlsymLookup());
case kOatAddressQuickIMTConflictTrampoline:
return static_cast<const uint8_t*>(header.GetQuickImtConflictTrampoline());
case kOatAddressQuickResolutionTrampoline:
return static_cast<const uint8_t*>(header.GetQuickResolutionTrampoline());
case kOatAddressQuickToInterpreterBridge:
return static_cast<const uint8_t*>(header.GetQuickToInterpreterBridge());
default:
UNREACHABLE();
}
}
const ImageInfo& primary_image_info = GetImageInfo(0);
return GetOatAddressForOffset(primary_image_info.oat_address_offsets_[type], primary_image_info);
}
const uint8_t* ImageWriter::GetQuickCode(ArtMethod* method,
const ImageInfo& image_info,
bool* quick_is_interpreted) {
DCHECK(!method->IsResolutionMethod()) << PrettyMethod(method);
DCHECK_NE(method, Runtime::Current()->GetImtConflictMethod()) << PrettyMethod(method);
DCHECK(!method->IsImtUnimplementedMethod()) << PrettyMethod(method);
DCHECK(method->IsInvokable()) << PrettyMethod(method);
DCHECK(!IsInBootImage(method)) << PrettyMethod(method);
// Use original code if it exists. Otherwise, set the code pointer to the resolution
// trampoline.
// Quick entrypoint:
const void* quick_oat_entry_point =
method->GetEntryPointFromQuickCompiledCodePtrSize(target_ptr_size_);
const uint8_t* quick_code;
if (UNLIKELY(IsInBootImage(method->GetDeclaringClass()))) {
DCHECK(method->IsCopied());
// If the code is not in the oat file corresponding to this image (e.g. default methods)
quick_code = reinterpret_cast<const uint8_t*>(quick_oat_entry_point);
} else {
uint32_t quick_oat_code_offset = PointerToLowMemUInt32(quick_oat_entry_point);
quick_code = GetOatAddressForOffset(quick_oat_code_offset, image_info);
}
*quick_is_interpreted = false;
if (quick_code != nullptr && (!method->IsStatic() || method->IsConstructor() ||
method->GetDeclaringClass()->IsInitialized())) {
// We have code for a non-static or initialized method, just use the code.
} else if (quick_code == nullptr && method->IsNative() &&
(!method->IsStatic() || method->GetDeclaringClass()->IsInitialized())) {
// Non-static or initialized native method missing compiled code, use generic JNI version.
quick_code = GetOatAddress(kOatAddressQuickGenericJNITrampoline);
} else if (quick_code == nullptr && !method->IsNative()) {
// We don't have code at all for a non-native method, use the interpreter.
quick_code = GetOatAddress(kOatAddressQuickToInterpreterBridge);
*quick_is_interpreted = true;
} else {
CHECK(!method->GetDeclaringClass()->IsInitialized());
// We have code for a static method, but need to go through the resolution stub for class
// initialization.
quick_code = GetOatAddress(kOatAddressQuickResolutionTrampoline);
}
if (!IsInBootOatFile(quick_code)) {
// DCHECK_GE(quick_code, oat_data_begin_);
}
return quick_code;
}
void ImageWriter::CopyAndFixupMethod(ArtMethod* orig,
ArtMethod* copy,
const ImageInfo& image_info) {
memcpy(copy, orig, ArtMethod::Size(target_ptr_size_));
copy->SetDeclaringClass(GetImageAddress(orig->GetDeclaringClassUnchecked()));
ArtMethod** orig_resolved_methods = orig->GetDexCacheResolvedMethods(target_ptr_size_);
copy->SetDexCacheResolvedMethods(NativeLocationInImage(orig_resolved_methods), target_ptr_size_);
GcRoot<mirror::Class>* orig_resolved_types = orig->GetDexCacheResolvedTypes(target_ptr_size_);
copy->SetDexCacheResolvedTypes(NativeLocationInImage(orig_resolved_types), target_ptr_size_);
// OatWriter replaces the code_ with an offset value. Here we re-adjust to a pointer relative to
// oat_begin_
// The resolution method has a special trampoline to call.
Runtime* runtime = Runtime::Current();
if (UNLIKELY(orig == runtime->GetResolutionMethod())) {
copy->SetEntryPointFromQuickCompiledCodePtrSize(
GetOatAddress(kOatAddressQuickResolutionTrampoline), target_ptr_size_);
} else if (UNLIKELY(orig == runtime->GetImtConflictMethod() ||
orig == runtime->GetImtUnimplementedMethod())) {
copy->SetEntryPointFromQuickCompiledCodePtrSize(
GetOatAddress(kOatAddressQuickIMTConflictTrampoline), target_ptr_size_);
} else if (UNLIKELY(orig->IsRuntimeMethod())) {
bool found_one = false;
for (size_t i = 0; i < static_cast<size_t>(Runtime::kLastCalleeSaveType); ++i) {
auto idx = static_cast<Runtime::CalleeSaveType>(i);
if (runtime->HasCalleeSaveMethod(idx) && runtime->GetCalleeSaveMethod(idx) == orig) {
found_one = true;
break;
}
}
CHECK(found_one) << "Expected to find callee save method but got " << PrettyMethod(orig);
CHECK(copy->IsRuntimeMethod());
} else {
// We assume all methods have code. If they don't currently then we set them to the use the
// resolution trampoline. Abstract methods never have code and so we need to make sure their
// use results in an AbstractMethodError. We use the interpreter to achieve this.
if (UNLIKELY(!orig->IsInvokable())) {
copy->SetEntryPointFromQuickCompiledCodePtrSize(
GetOatAddress(kOatAddressQuickToInterpreterBridge), target_ptr_size_);
} else {
bool quick_is_interpreted;
const uint8_t* quick_code = GetQuickCode(orig, image_info, &quick_is_interpreted);
copy->SetEntryPointFromQuickCompiledCodePtrSize(quick_code, target_ptr_size_);
// JNI entrypoint:
if (orig->IsNative()) {
// The native method's pointer is set to a stub to lookup via dlsym.
// Note this is not the code_ pointer, that is handled above.
copy->SetEntryPointFromJniPtrSize(
GetOatAddress(kOatAddressJNIDlsymLookup), target_ptr_size_);
}
}
}
}
size_t ImageWriter::GetBinSizeSum(ImageWriter::ImageInfo& image_info, ImageWriter::Bin up_to) const {
DCHECK_LE(up_to, kBinSize);
return std::accumulate(&image_info.bin_slot_sizes_[0],
&image_info.bin_slot_sizes_[up_to],
/*init*/0);
}
ImageWriter::BinSlot::BinSlot(uint32_t lockword) : lockword_(lockword) {
// These values may need to get updated if more bins are added to the enum Bin
static_assert(kBinBits == 3, "wrong number of bin bits");
static_assert(kBinShift == 27, "wrong number of shift");
static_assert(sizeof(BinSlot) == sizeof(LockWord), "BinSlot/LockWord must have equal sizes");
DCHECK_LT(GetBin(), kBinSize);
DCHECK_ALIGNED(GetIndex(), kObjectAlignment);
}
ImageWriter::BinSlot::BinSlot(Bin bin, uint32_t index)
: BinSlot(index | (static_cast<uint32_t>(bin) << kBinShift)) {
DCHECK_EQ(index, GetIndex());
}
ImageWriter::Bin ImageWriter::BinSlot::GetBin() const {
return static_cast<Bin>((lockword_ & kBinMask) >> kBinShift);
}
uint32_t ImageWriter::BinSlot::GetIndex() const {
return lockword_ & ~kBinMask;
}
ImageWriter::Bin ImageWriter::BinTypeForNativeRelocationType(NativeObjectRelocationType type) {
switch (type) {
case kNativeObjectRelocationTypeArtField:
case kNativeObjectRelocationTypeArtFieldArray:
return kBinArtField;
case kNativeObjectRelocationTypeArtMethodClean:
case kNativeObjectRelocationTypeArtMethodArrayClean:
return kBinArtMethodClean;
case kNativeObjectRelocationTypeArtMethodDirty:
case kNativeObjectRelocationTypeArtMethodArrayDirty:
return kBinArtMethodDirty;
case kNativeObjectRelocationTypeDexCacheArray:
return kBinDexCacheArray;
}
UNREACHABLE();
}
size_t ImageWriter::GetOatIndex(mirror::Object* obj) const {
if (compile_app_image_) {
return GetDefaultOatIndex();
} else {
mirror::DexCache* dex_cache =
obj->IsDexCache() ? obj->AsDexCache()
: obj->IsClass() ? obj->AsClass()->GetDexCache()
: obj->GetClass()->GetDexCache();
return GetOatIndexForDexCache(dex_cache);
}
}
size_t ImageWriter::GetOatIndexForDexFile(const DexFile* dex_file) const {
if (compile_app_image_) {
return GetDefaultOatIndex();
} else {
auto it = dex_file_oat_index_map_.find(dex_file);
DCHECK(it != dex_file_oat_index_map_.end()) << dex_file->GetLocation();
return it->second;
}
}
size_t ImageWriter::GetOatIndexForDexCache(mirror::DexCache* dex_cache) const {
if (dex_cache == nullptr) {
return GetDefaultOatIndex();
} else {
return GetOatIndexForDexFile(dex_cache->GetDexFile());
}
}
void ImageWriter::UpdateOatFileLayout(size_t oat_index,
size_t oat_loaded_size,
size_t oat_data_offset,
size_t oat_data_size) {
const uint8_t* images_end = image_infos_.back().image_begin_ + image_infos_.back().image_size_;
for (const ImageInfo& info : image_infos_) {
DCHECK_LE(info.image_begin_ + info.image_size_, images_end);
}
DCHECK(images_end != nullptr); // Image space must be ready.
ImageInfo& cur_image_info = GetImageInfo(oat_index);
cur_image_info.oat_file_begin_ = images_end + cur_image_info.oat_offset_;
cur_image_info.oat_loaded_size_ = oat_loaded_size;
cur_image_info.oat_data_begin_ = cur_image_info.oat_file_begin_ + oat_data_offset;
cur_image_info.oat_size_ = oat_data_size;
if (compile_app_image_) {
CHECK_EQ(oat_filenames_.size(), 1u) << "App image should have no next image.";
return;
}
// Update the oat_offset of the next image info.
if (oat_index + 1u != oat_filenames_.size()) {
// There is a following one.
ImageInfo& next_image_info = GetImageInfo(oat_index + 1u);
next_image_info.oat_offset_ = cur_image_info.oat_offset_ + oat_loaded_size;
}
}
void ImageWriter::UpdateOatFileHeader(size_t oat_index, const OatHeader& oat_header) {
ImageInfo& cur_image_info = GetImageInfo(oat_index);
cur_image_info.oat_checksum_ = oat_header.GetChecksum();
if (oat_index == GetDefaultOatIndex()) {
// Primary oat file, read the trampolines.
cur_image_info.oat_address_offsets_[kOatAddressInterpreterToInterpreterBridge] =
oat_header.GetInterpreterToInterpreterBridgeOffset();
cur_image_info.oat_address_offsets_[kOatAddressInterpreterToCompiledCodeBridge] =
oat_header.GetInterpreterToCompiledCodeBridgeOffset();
cur_image_info.oat_address_offsets_[kOatAddressJNIDlsymLookup] =
oat_header.GetJniDlsymLookupOffset();
cur_image_info.oat_address_offsets_[kOatAddressQuickGenericJNITrampoline] =
oat_header.GetQuickGenericJniTrampolineOffset();
cur_image_info.oat_address_offsets_[kOatAddressQuickIMTConflictTrampoline] =
oat_header.GetQuickImtConflictTrampolineOffset();
cur_image_info.oat_address_offsets_[kOatAddressQuickResolutionTrampoline] =
oat_header.GetQuickResolutionTrampolineOffset();
cur_image_info.oat_address_offsets_[kOatAddressQuickToInterpreterBridge] =
oat_header.GetQuickToInterpreterBridgeOffset();
}
}
ImageWriter::ImageWriter(
const CompilerDriver& compiler_driver,
uintptr_t image_begin,
bool compile_pic,
bool compile_app_image,
ImageHeader::StorageMode image_storage_mode,
const std::vector<const char*>& oat_filenames,
const std::unordered_map<const DexFile*, size_t>& dex_file_oat_index_map)
: compiler_driver_(compiler_driver),
global_image_begin_(reinterpret_cast<uint8_t*>(image_begin)),
image_objects_offset_begin_(0),
compile_pic_(compile_pic),
compile_app_image_(compile_app_image),
target_ptr_size_(InstructionSetPointerSize(compiler_driver_.GetInstructionSet())),
image_infos_(oat_filenames.size()),
image_method_array_(ImageHeader::kImageMethodsCount),
dirty_methods_(0u),
clean_methods_(0u),
image_storage_mode_(image_storage_mode),
oat_filenames_(oat_filenames),
dex_file_oat_index_map_(dex_file_oat_index_map) {
CHECK_NE(image_begin, 0U);
std::fill_n(image_methods_, arraysize(image_methods_), nullptr);
CHECK_EQ(compile_app_image, !Runtime::Current()->GetHeap()->GetBootImageSpaces().empty())
<< "Compiling a boot image should occur iff there are no boot image spaces loaded";
}
ImageWriter::ImageInfo::ImageInfo()
: intern_table_(new InternTable),
class_table_(new ClassTable) {}
} // namespace art