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LeafOS / LeafOS-Project / android_art / 35f31c697e1873a7d6ed600d6fff7932730325ea / . / dex2oat / linker / image_writer.cc
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/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "image_writer.h"
#include <lz4.h>
#include <lz4hc.h>
#include <sys/stat.h>
#include <memory>
#include <numeric>
#include <unordered_set>
#include <vector>
#include "art_field-inl.h"
#include "art_method-inl.h"
#include "base/bit_memory_region.h"
#include "base/callee_save_type.h"
#include "base/enums.h"
#include "base/globals.h"
#include "base/logging.h" // For VLOG.
#include "base/unix_file/fd_file.h"
#include "class_linker-inl.h"
#include "class_root.h"
#include "compiled_method.h"
#include "dex/dex_file-inl.h"
#include "dex/dex_file_types.h"
#include "driver/compiler_options.h"
#include "elf_file.h"
#include "elf_utils.h"
#include "gc/accounting/card_table-inl.h"
#include "gc/accounting/heap_bitmap.h"
#include "gc/accounting/space_bitmap-inl.h"
#include "gc/collector/concurrent_copying.h"
#include "gc/heap-visit-objects-inl.h"
#include "gc/heap.h"
#include "gc/space/large_object_space.h"
#include "gc/space/space-inl.h"
#include "gc/verification.h"
#include "handle_scope-inl.h"
#include "image.h"
#include "imt_conflict_table.h"
#include "jni/jni_internal.h"
#include "linear_alloc.h"
#include "lock_word.h"
#include "mirror/array-inl.h"
#include "mirror/class-inl.h"
#include "mirror/class_ext.h"
#include "mirror/class_loader.h"
#include "mirror/dex_cache-inl.h"
#include "mirror/dex_cache.h"
#include "mirror/executable.h"
#include "mirror/method.h"
#include "mirror/object-inl.h"
#include "mirror/object-refvisitor-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 "optimizing/intrinsic_objects.h"
#include "runtime.h"
#include "scoped_thread_state_change-inl.h"
#include "subtype_check.h"
#include "utils/dex_cache_arrays_layout-inl.h"
#include "well_known_classes.h"
using ::art::mirror::Class;
using ::art::mirror::DexCache;
using ::art::mirror::Object;
using ::art::mirror::ObjectArray;
using ::art::mirror::String;
namespace art {
namespace linker {
static inline size_t RelocationIndex(size_t relocation_offset, PointerSize target_ptr_size) {
static_assert(sizeof(GcRoot<mirror::Object>) == sizeof(mirror::HeapReference<mirror::Object>),
"Expecting heap GC roots and references to have the same size.");
DCHECK_LE(sizeof(GcRoot<mirror::Object>), static_cast<size_t>(target_ptr_size));
DCHECK_ALIGNED(relocation_offset, sizeof(GcRoot<mirror::Object>));
return relocation_offset / sizeof(GcRoot<mirror::Object>);
}
static ArrayRef<const uint8_t> MaybeCompressData(ArrayRef<const uint8_t> source,
ImageHeader::StorageMode image_storage_mode,
/*out*/ std::vector<uint8_t>* storage) {
const uint64_t compress_start_time = NanoTime();
switch (image_storage_mode) {
case ImageHeader::kStorageModeLZ4: {
storage->resize(LZ4_compressBound(source.size()));
size_t data_size = LZ4_compress_default(
reinterpret_cast<char*>(const_cast<uint8_t*>(source.data())),
reinterpret_cast<char*>(storage->data()),
source.size(),
storage->size());
storage->resize(data_size);
break;
}
case ImageHeader::kStorageModeLZ4HC: {
// Bound is same as non HC.
storage->resize(LZ4_compressBound(source.size()));
size_t data_size = LZ4_compress_HC(
reinterpret_cast<const char*>(const_cast<uint8_t*>(source.data())),
reinterpret_cast<char*>(storage->data()),
source.size(),
storage->size(),
LZ4HC_CLEVEL_MAX);
storage->resize(data_size);
break;
}
case ImageHeader::kStorageModeUncompressed: {
return source;
}
default: {
LOG(FATAL) << "Unsupported";
UNREACHABLE();
}
}
DCHECK(image_storage_mode == ImageHeader::kStorageModeLZ4 ||
image_storage_mode == ImageHeader::kStorageModeLZ4HC);
VLOG(compiler) << "Compressed from " << source.size() << " to " << storage->size() << " in "
<< PrettyDuration(NanoTime() - compress_start_time);
if (kIsDebugBuild) {
std::vector<uint8_t> decompressed(source.size());
const size_t decompressed_size = LZ4_decompress_safe(
reinterpret_cast<char*>(storage->data()),
reinterpret_cast<char*>(decompressed.data()),
storage->size(),
decompressed.size());
CHECK_EQ(decompressed_size, decompressed.size());
CHECK_EQ(memcmp(source.data(), decompressed.data(), source.size()), 0) << image_storage_mode;
}
return ArrayRef<const uint8_t>(*storage);
}
// 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 ClearDexFileCookies() REQUIRES_SHARED(Locks::mutator_lock_) {
auto visitor = [](Object* obj) REQUIRES_SHARED(Locks::mutator_lock_) {
DCHECK(obj != nullptr);
Class* klass = obj->GetClass();
if (klass == WellKnownClasses::ToClass(WellKnownClasses::dalvik_system_DexFile)) {
ArtField* field = jni::DecodeArtField(WellKnownClasses::dalvik_system_DexFile_cookie);
// Null out the cookie to enable determinism. b/34090128
field->SetObject</*kTransactionActive*/false>(obj, nullptr);
}
};
Runtime::Current()->GetHeap()->VisitObjects(visitor);
}
bool ImageWriter::PrepareImageAddressSpace(TimingLogger* timings) {
target_ptr_size_ = InstructionSetPointerSize(compiler_options_.GetInstructionSet());
Thread* const self = Thread::Current();
gc::Heap* const heap = Runtime::Current()->GetHeap();
{
ScopedObjectAccess soa(self);
{
TimingLogger::ScopedTiming t("PruneNonImageClasses", timings);
PruneNonImageClasses(); // Remove junk
}
if (compile_app_image_) {
TimingLogger::ScopedTiming t("ClearDexFileCookies", timings);
// Clear dex file cookies for app images to enable app image determinism. This is required
// since the cookie field contains long pointers to DexFiles which are not deterministic.
// b/34090128
ClearDexFileCookies();
}
}
{
TimingLogger::ScopedTiming t("CollectGarbage", timings);
heap->CollectGarbage(/* clear_soft_references */ false); // Remove garbage.
}
if (kIsDebugBuild) {
ScopedObjectAccess soa(self);
CheckNonImageClassesRemoved();
}
// Used to store information that will later be used to calculate image
// offsets to string references in the AppImage.
std::vector<RefInfoPair> string_ref_info;
if (ClassLinker::kAppImageMayContainStrings && compile_app_image_) {
// Count the number of string fields so we can allocate the appropriate
// amount of space in the image section.
TimingLogger::ScopedTiming t("AppImage:CollectStringReferenceInfo", timings);
ScopedObjectAccess soa(self);
if (kIsDebugBuild) {
VerifyNativeGCRootInvariants();
CHECK_EQ(image_infos_.size(), 1u);
}
string_ref_info = CollectStringReferenceInfo();
image_infos_.back().num_string_references_ = string_ref_info.size();
}
{
TimingLogger::ScopedTiming t("CalculateNewObjectOffsets", timings);
ScopedObjectAccess soa(self);
CalculateNewObjectOffsets();
}
// Obtain class count for debugging purposes
if (VLOG_IS_ON(compiler) && compile_app_image_) {
ScopedObjectAccess soa(self);
size_t app_image_class_count = 0;
for (ImageInfo& info : image_infos_) {
info.class_table_->Visit([&](ObjPtr<mirror::Class> klass)
REQUIRES_SHARED(Locks::mutator_lock_) {
if (!IsInBootImage(klass.Ptr())) {
++app_image_class_count;
}
// Indicate that we would like to continue visiting classes.
return true;
});
}
VLOG(compiler) << "Dex2Oat:AppImage:classCount = " << app_image_class_count;
}
if (ClassLinker::kAppImageMayContainStrings && compile_app_image_) {
// Use the string reference information obtained earlier to calculate image
// offsets. These will later be written to the image by Write/CopyMetadata.
TimingLogger::ScopedTiming t("AppImage:CalculateImageOffsets", timings);
ScopedObjectAccess soa(self);
size_t managed_string_refs = 0,
native_string_refs = 0;
/*
* Iterate over the string reference info and calculate image offsets.
* The first element of the pair is the object the reference belongs to
* and the second element is the offset to the field. If the offset has
* a native ref tag 1) the object is a DexCache and 2) the offset needs
* to be calculated using the relocation information for the DexCache's
* strings array.
*/
for (const RefInfoPair& ref_info : string_ref_info) {
uint32_t image_offset;
if (HasNativeRefTag(ref_info.second)) {
++native_string_refs;
// Only DexCaches can contain native references to Java strings.
ObjPtr<mirror::DexCache> dex_cache(ref_info.first->AsDexCache());
// No need to set or clear native ref tags. The existing tag will be
// carried forward.
image_offset = native_object_relocations_[dex_cache->GetStrings()].offset +
ref_info.second;
} else {
++managed_string_refs;
image_offset = GetImageOffset(ref_info.first) + ref_info.second;
}
string_reference_offsets_.push_back(image_offset);
}
CHECK_EQ(image_infos_.back().num_string_references_,
string_reference_offsets_.size());
VLOG(compiler) << "Dex2Oat:AppImage:stringReferences = " << string_reference_offsets_.size();
VLOG(compiler) << "Dex2Oat:AppImage:managedStringReferences = " << managed_string_refs;
VLOG(compiler) << "Dex2Oat:AppImage:nativeStringReferences = " << native_string_refs;
}
// This needs to happen after CalculateNewObjectOffsets since it relies on intern_table_bytes_ and
// bin size sums being calculated.
TimingLogger::ScopedTiming t("AllocMemory", timings);
if (!AllocMemory()) {
return false;
}
return true;
}
class ImageWriter::CollectStringReferenceVisitor {
public:
explicit CollectStringReferenceVisitor(const ImageWriter& image_writer)
: dex_cache_string_ref_counter_(0),
image_writer_(image_writer) {}
// Used to prevent repeated null checks in the code that calls the visitor.
ALWAYS_INLINE
void VisitRootIfNonNull(mirror::CompressedReference<mirror::Object>* root) const
REQUIRES_SHARED(Locks::mutator_lock_) {
if (!root->IsNull()) {
VisitRoot(root);
}
}
/*
* Counts the number of native references to strings reachable through
* DexCache objects for verification later.
*/
ALWAYS_INLINE
void VisitRoot(mirror::CompressedReference<mirror::Object>* root) const
REQUIRES_SHARED(Locks::mutator_lock_) {
ObjPtr<mirror::Object> referred_obj = root->AsMirrorPtr();
if (curr_obj_->IsDexCache() &&
image_writer_.IsValidAppImageStringReference(referred_obj)) {
++dex_cache_string_ref_counter_;
}
}
// Collects info for Java fields that reference Java Strings.
ALWAYS_INLINE
void operator() (ObjPtr<mirror::Object> obj,
MemberOffset member_offset,
bool is_static ATTRIBUTE_UNUSED) const
REQUIRES_SHARED(Locks::mutator_lock_) {
ObjPtr<mirror::Object> referred_obj =
obj->GetFieldObject<mirror::Object, kVerifyNone, kWithoutReadBarrier>(
member_offset);
if (image_writer_.IsValidAppImageStringReference(referred_obj)) {
string_ref_info_.emplace_back(obj.Ptr(), member_offset.Uint32Value());
}
}
ALWAYS_INLINE
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);
}
// Used by the wrapper function to obtain a native reference count.
size_t GetDexCacheStringRefCounter() const {
return dex_cache_string_ref_counter_;
}
// Resets the native reference count.
void ResetDexCacheStringRefCounter() {
dex_cache_string_ref_counter_ = 0;
}
ObjPtr<mirror::Object> curr_obj_;
mutable std::vector<RefInfoPair> string_ref_info_;
private:
mutable size_t dex_cache_string_ref_counter_;
const ImageWriter& image_writer_;
};
std::vector<ImageWriter::RefInfoPair> ImageWriter::CollectStringReferenceInfo() const
REQUIRES_SHARED(Locks::mutator_lock_) {
gc::Heap* const heap = Runtime::Current()->GetHeap();
CollectStringReferenceVisitor visitor(*this);
heap->VisitObjects([this, &visitor](ObjPtr<mirror::Object> object)
REQUIRES_SHARED(Locks::mutator_lock_) {
if (!IsInBootImage(object.Ptr())) {
// Many native GC roots are wrapped in std::atomics. Due to the
// semantics of atomic objects we can't actually visit the addresses of
// the native GC roots. Instead the visiting functions will pass the
// visitor the address of a temporary copy of the native GC root and, if
// it is changed, copy it back into the original location.
//
// This analysis requires the actual address of the native GC root so
// we will only count them in the visitor and then collect them manually
// afterwards. This count will then be used to verify that we collected
// all native GC roots.
visitor.curr_obj_ = object;
if (object->IsDexCache()) {
object->VisitReferences</* kVisitNativeRoots */ true,
kVerifyNone,
kWithoutReadBarrier>(visitor, visitor);
ObjPtr<mirror::DexCache> dex_cache = object->AsDexCache();
size_t new_native_ref_counter = 0;
for (size_t string_index = 0; string_index < dex_cache->NumStrings(); ++string_index) {
mirror::StringDexCachePair dc_pair = dex_cache->GetStrings()[string_index].load();
mirror::Object* referred_obj = dc_pair.object.AddressWithoutBarrier()->AsMirrorPtr();
if (IsValidAppImageStringReference(referred_obj)) {
++new_native_ref_counter;
uint32_t string_vector_offset =
(string_index * sizeof(mirror::StringDexCachePair)) +
offsetof(mirror::StringDexCachePair, object);
visitor.string_ref_info_.emplace_back(object.Ptr(),
SetNativeRefTag(string_vector_offset));
}
}
CHECK_EQ(visitor.GetDexCacheStringRefCounter(), new_native_ref_counter);
} else {
object->VisitReferences</* kVisitNativeRoots */ false,
kVerifyNone,
kWithoutReadBarrier>(visitor, visitor);
}
visitor.ResetDexCacheStringRefCounter();
}
});
return std::move(visitor.string_ref_info_);
}
class ImageWriter::NativeGCRootInvariantVisitor {
public:
explicit NativeGCRootInvariantVisitor(const ImageWriter& image_writer) :
image_writer_(image_writer) {}
ALWAYS_INLINE
void VisitRootIfNonNull(mirror::CompressedReference<mirror::Object>* root) const
REQUIRES_SHARED(Locks::mutator_lock_) {
if (!root->IsNull()) {
VisitRoot(root);
}
}
ALWAYS_INLINE
void VisitRoot(mirror::CompressedReference<mirror::Object>* root) const
REQUIRES_SHARED(Locks::mutator_lock_) {
ObjPtr<mirror::Object> referred_obj = root->AsMirrorPtr();
if (curr_obj_->IsClass()) {
class_violation = class_violation ||
image_writer_.IsValidAppImageStringReference(referred_obj);
} else if (curr_obj_->IsClassLoader()) {
class_loader_violation = class_loader_violation ||
image_writer_.IsValidAppImageStringReference(referred_obj);
} else if (!curr_obj_->IsDexCache()) {
LOG(FATAL) << "Dex2Oat:AppImage | " <<
"Native reference to String found in unexpected object type.";
}
}
ALWAYS_INLINE
void operator() (ObjPtr<mirror::Object> obj ATTRIBUTE_UNUSED,
MemberOffset member_offset ATTRIBUTE_UNUSED,
bool is_static ATTRIBUTE_UNUSED) const
REQUIRES_SHARED(Locks::mutator_lock_) {}
ALWAYS_INLINE
void operator() (ObjPtr<mirror::Class> klass ATTRIBUTE_UNUSED,
ObjPtr<mirror::Reference> ref ATTRIBUTE_UNUSED) const
REQUIRES_SHARED(Locks::mutator_lock_) {}
// Returns true iff the only reachable native string references are through DexCache objects.
bool InvariantsHold() const {
return !(class_violation || class_loader_violation);
}
ObjPtr<mirror::Object> curr_obj_;
mutable bool class_violation = false,
class_loader_violation = false;
private:
const ImageWriter& image_writer_;
};
void ImageWriter::VerifyNativeGCRootInvariants() const REQUIRES_SHARED(Locks::mutator_lock_) {
gc::Heap* const heap = Runtime::Current()->GetHeap();
NativeGCRootInvariantVisitor visitor(*this);
heap->VisitObjects([this, &visitor](ObjPtr<mirror::Object> object)
REQUIRES_SHARED(Locks::mutator_lock_) {
visitor.curr_obj_ = object;
if (!IsInBootImage(object.Ptr())) {
object->VisitReferences</* kVisitNativeRefernces */ true,
kVerifyNone,
kWithoutReadBarrier>(visitor, visitor);
}
});
bool error = false;
std::ostringstream error_str;
/*
* Build the error string
*/
if (UNLIKELY(visitor.class_violation)) {
error_str << "Class";
error = true;
}
if (UNLIKELY(visitor.class_loader_violation)) {
if (error) {
error_str << ", ";
}
error_str << "ClassLoader";
}
CHECK(visitor.InvariantsHold()) <<
"Native GC root invariant failure. String refs reachable through the following objects: " <<
error_str.str();
}
void ImageWriter::CopyMetadata() {
CHECK(compile_app_image_);
CHECK_EQ(image_infos_.size(), 1u);
const ImageInfo& image_info = image_infos_.back();
std::vector<ImageSection> image_sections = image_info.CreateImageSections().second;
uint32_t* sfo_section_base = reinterpret_cast<uint32_t*>(
image_info.image_.Begin() +
image_sections[ImageHeader::kSectionStringReferenceOffsets].Offset());
std::copy(string_reference_offsets_.begin(),
string_reference_offsets_.end(),
sfo_section_base);
}
bool ImageWriter::IsValidAppImageStringReference(ObjPtr<mirror::Object> referred_obj) const {
return referred_obj != nullptr &&
!IsInBootImage(referred_obj.Ptr()) &&
referred_obj->IsString();
}
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();
}
if (compile_app_image_) {
CopyMetadata();
}
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;
}
// Image data size excludes the bitmap and the header.
ImageHeader* const image_header = reinterpret_cast<ImageHeader*>(image_info.image_.Begin());
ArrayRef<const uint8_t> raw_image_data(image_info.image_.Begin() + sizeof(ImageHeader),
image_header->GetImageSize() - sizeof(ImageHeader));
CHECK_EQ(image_header->storage_mode_, image_storage_mode_);
std::vector<uint8_t> compressed_data;
ArrayRef<const uint8_t> image_data =
MaybeCompressData(raw_image_data, image_storage_mode_, &compressed_data);
// Write out the image + fields + methods.
if (!image_file->PwriteFully(image_data.data(), image_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->GetImageBitmapSection();
// Align up since data size may be unaligned if the image is compressed.
size_t bitmap_position_in_file = RoundUp(sizeof(ImageHeader) + image_data.size(), kPageSize);
if (image_storage_mode_ == ImageHeader::kDefaultStorageMode) {
CHECK_EQ(bitmap_position_in_file, bitmap_section.Offset());
}
if (!image_file->PwriteFully(image_info.image_bitmap_->Begin(),
bitmap_section.Size(),
bitmap_position_in_file)) {
PLOG(ERROR) << "Failed to write image file bitmap " << image_filename;
image_file->Erase();
return false;
}
// Write out relocations.
size_t relocations_position_in_file = bitmap_position_in_file + bitmap_section.Size();
ArrayRef<const uint8_t> relocations = MaybeCompressData(
ArrayRef<const uint8_t>(image_info.relocation_bitmap_),
image_storage_mode_,
&compressed_data);
image_header->sections_[ImageHeader::kSectionImageRelocations] =
ImageSection(bitmap_section.Offset() + bitmap_section.Size(), relocations.size());
if (!image_file->PwriteFully(relocations.data(),
relocations.size(),
relocations_position_in_file)) {
PLOG(ERROR) << "Failed to write image file relocations " << 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_ = image_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;
}
if (VLOG_IS_ON(compiler)) {
size_t separately_written_section_size = bitmap_section.Size() +
image_header->GetImageRelocationsSection().Size() +
sizeof(ImageHeader);
size_t total_uncompressed_size = raw_image_data.size() + separately_written_section_size,
total_compressed_size = image_data.size() + separately_written_section_size;
VLOG(compiler) << "Dex2Oat:uncompressedImageSize = " << total_uncompressed_size;
if (total_uncompressed_size != total_compressed_size) {
VLOG(compiler) << "Dex2Oat:compressedImageSize = " << total_compressed_size;
}
}
CHECK_EQ(relocations_position_in_file + relocations.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.GetBinSlotOffset(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.
LockWord lw(object->GetLockWord(false));
switch (lw.GetState()) {
case LockWord::kFatLocked:
FALLTHROUGH_INTENDED;
case LockWord::kThinLocked: {
std::ostringstream oss;
bool thin = (lw.GetState() == LockWord::kThinLocked);
oss << (thin ? "Thin" : "Fat")
<< " locked object " << object << "(" << object->PrettyTypeOf()
<< ") found during object copy";
if (thin) {
oss << ". Lock owner:" << lw.ThinLockOwner();
}
LOG(FATAL) << oss.str();
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 CompilerOptions.
// 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_options_.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.GetBinSlotSize(Bin::kDexCacheArray));
DexCacheArraysLayout layout(target_ptr_size_, dex_file);
image_info.IncrementBinSlotSize(Bin::kDexCacheArray, layout.Size());
}
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
Thread* const self = Thread::Current();
ReaderMutexLock mu(self, *Locks::dex_lock_);
for (const ClassLinker::DexCacheData& data : class_linker->GetDexCachesData()) {
ObjPtr<mirror::DexCache> dex_cache =
ObjPtr<mirror::DexCache>::DownCast(self->DecodeJObject(data.weak_root));
if (dex_cache == nullptr || IsInBootImage(dex_cache.Ptr())) {
continue;
}
const DexFile* dex_file = dex_cache->GetDexFile();
CHECK(dex_file_oat_index_map_.find(dex_file) != dex_file_oat_index_map_.end())
<< "Dex cache should have been pruned " << dex_file->GetLocation()
<< "; possibly in class path";
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(),
oat_index);
DCHECK_EQ(dex_file->NumMethodIds() != 0u, dex_cache->GetResolvedMethods() != nullptr);
AddDexCacheArrayRelocation(dex_cache->GetResolvedMethods(),
start + layout.MethodsOffset(),
oat_index);
DCHECK_EQ(dex_file->NumFieldIds() != 0u, dex_cache->GetResolvedFields() != nullptr);
AddDexCacheArrayRelocation(dex_cache->GetResolvedFields(),
start + layout.FieldsOffset(),
oat_index);
DCHECK_EQ(dex_file->NumStringIds() != 0u, dex_cache->GetStrings() != nullptr);
AddDexCacheArrayRelocation(dex_cache->GetStrings(), start + layout.StringsOffset(), oat_index);
if (dex_cache->GetResolvedMethodTypes() != nullptr) {
AddDexCacheArrayRelocation(dex_cache->GetResolvedMethodTypes(),
start + layout.MethodTypesOffset(),
oat_index);
}
if (dex_cache->GetResolvedCallSites() != nullptr) {
AddDexCacheArrayRelocation(dex_cache->GetResolvedCallSites(),
start + layout.CallSitesOffset(),
oat_index);
}
}
}
void ImageWriter::AddDexCacheArrayRelocation(void* array,
size_t offset,
size_t oat_index) {
if (array != nullptr) {
DCHECK(!IsInBootImage(array));
native_object_relocations_.emplace(array,
NativeObjectRelocation { oat_index, offset, NativeObjectRelocationType::kDexCacheArray });
}
}
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()) {
ObjPtr<mirror::Class> klass = method->GetDeclaringClass();
CHECK(klass == nullptr || KeepClass(klass))
<< Class::PrettyClass(klass) << " should be a kept class";
}
}
}
// kBinArtMethodClean picked arbitrarily, just required to differentiate between ArtFields and
// ArtMethods.
pointer_arrays_.emplace(arr, Bin::kArtMethodClean);
}
void ImageWriter::AssignImageBinSlot(mirror::Object* object, size_t oat_index) {
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 = Bin::kRegular;
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 = Bin::kClassVerified;
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));
}
}
}
// Move known dirty objects into their own sections. This includes:
// - classes with dirty static fields.
if (dirty_image_objects_ != nullptr &&
dirty_image_objects_->find(klass->PrettyDescriptor()) != dirty_image_objects_->end()) {
bin = Bin::kKnownDirty;
} else if (klass->GetStatus() == ClassStatus::kInitialized) {
bin = Bin::kClassInitialized;
// 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 = Bin::kClassInitializedFinalStatics;
} 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 = Bin::kClassInitializedFinalStatics;
}
}
}
} else if (object->GetClass<kVerifyNone>()->IsStringClass()) {
bin = Bin::kString; // Strings are almost always immutable (except for object header).
} else if (object->GetClass<kVerifyNone>() == GetClassRoot<mirror::Object>()) {
// Instance of java lang object, probably a lock object. This means it will be dirty when we
// synchronize on it.
bin = Bin::kMiscDirty;
} else if (object->IsDexCache()) {
// Dex file field becomes dirty when the image is loaded.
bin = Bin::kMiscDirty;
}
// else bin = kBinRegular
}
// Assign the oat index too.
DCHECK(oat_index_map_.find(object) == oat_index_map_.end());
oat_index_map_.emplace(object, oat_index);
ImageInfo& image_info = GetImageInfo(oat_index);
size_t offset_delta = RoundUp(object_size, kObjectAlignment); // 64-bit alignment
// How many bytes the current bin is at (aligned).
size_t current_offset = image_info.GetBinSlotSize(bin);
// Move the current bin size up to accommodate the object we just assigned a bin slot.
image_info.IncrementBinSlotSize(bin, offset_delta);
BinSlot new_bin_slot(bin, current_offset);
SetImageBinSlot(object, new_bin_slot);
image_info.IncrementBinSlotCount(bin, 1u);
// 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;
}
ObjPtr<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() != ClassStatus::kInitialized;
}
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.GetBinSlotSize(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.GetBinSlotSize(bin_slot.GetBin()));
return bin_slot;
}
bool ImageWriter::AllocMemory() {
for (ImageInfo& image_info : image_infos_) {
const size_t length = RoundUp(image_info.CreateImageSections().first, kPageSize);
std::string error_msg;
image_info.image_ = MemMap::MapAnonymous("image writer image",
/* addr */ nullptr,
length,
PROT_READ | PROT_WRITE,
/* low_4gb */ false,
&error_msg);
if (UNLIKELY(!image_info.image_.IsValid())) {
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;
}
static bool IsBootClassLoaderClass(ObjPtr<mirror::Class> klass)
REQUIRES_SHARED(Locks::mutator_lock_) {
return klass->GetClassLoader() == nullptr;
}
bool ImageWriter::IsBootClassLoaderNonImageClass(mirror::Class* klass) {
return IsBootClassLoaderClass(klass) && !IsInBootImage(klass);
}
// This visitor follows the references of an instance, recursively then prune this class
// if a type of any field is pruned.
class ImageWriter::PruneObjectReferenceVisitor {
public:
PruneObjectReferenceVisitor(ImageWriter* image_writer,
bool* early_exit,
std::unordered_set<mirror::Object*>* visited,
bool* result)
: image_writer_(image_writer), early_exit_(early_exit), visited_(visited), result_(result) {}
ALWAYS_INLINE void VisitRootIfNonNull(
mirror::CompressedReference<mirror::Object>* root ATTRIBUTE_UNUSED) const
REQUIRES_SHARED(Locks::mutator_lock_) { }
ALWAYS_INLINE void VisitRoot(
mirror::CompressedReference<mirror::Object>* root ATTRIBUTE_UNUSED) const
REQUIRES_SHARED(Locks::mutator_lock_) { }
ALWAYS_INLINE void operator() (ObjPtr<mirror::Object> obj,
MemberOffset offset,
bool is_static ATTRIBUTE_UNUSED) const
REQUIRES_SHARED(Locks::mutator_lock_) {
mirror::Object* ref =
obj->GetFieldObject<mirror::Object, kVerifyNone, kWithoutReadBarrier>(offset);
if (ref == nullptr || visited_->find(ref) != visited_->end()) {
return;
}
ObjPtr<mirror::ObjectArray<mirror::Class>> class_roots =
Runtime::Current()->GetClassLinker()->GetClassRoots();
ObjPtr<mirror::Class> klass = ref->IsClass() ? ref->AsClass() : ref->GetClass();
if (klass == GetClassRoot<mirror::Method>(class_roots) ||
klass == GetClassRoot<mirror::Constructor>(class_roots)) {
// Prune all classes using reflection because the content they held will not be fixup.
*result_ = true;
}
if (ref->IsClass()) {
*result_ = *result_ ||
image_writer_->PruneAppImageClassInternal(ref->AsClass(), early_exit_, visited_);
} else {
// Record the object visited in case of circular reference.
visited_->emplace(ref);
*result_ = *result_ ||
image_writer_->PruneAppImageClassInternal(klass, early_exit_, visited_);
ref->VisitReferences(*this, *this);
// Clean up before exit for next call of this function.
visited_->erase(ref);
}
}
ALWAYS_INLINE 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);
}
ALWAYS_INLINE bool GetResult() const {
return result_;
}
private:
ImageWriter* image_writer_;
bool* early_exit_;
std::unordered_set<mirror::Object*>* visited_;
bool* const result_;
};
bool ImageWriter::PruneAppImageClass(ObjPtr<mirror::Class> klass) {
bool early_exit = false;
std::unordered_set<mirror::Object*> visited;
return PruneAppImageClassInternal(klass, &early_exit, &visited);
}
bool ImageWriter::PruneAppImageClassInternal(
ObjPtr<mirror::Class> klass,
bool* early_exit,
std::unordered_set<mirror::Object*>* visited) {
DCHECK(early_exit != nullptr);
DCHECK(visited != nullptr);
DCHECK(compile_app_image_);
if (klass == nullptr || IsInBootImage(klass.Ptr())) {
return false;
}
auto found = prune_class_memo_.find(klass.Ptr());
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.Ptr()) != visited->end()) {
*early_exit = true;
return false;
}
visited->emplace(klass.Ptr());
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_options_.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->IsErroneous()) {
result = true;
} else {
ObjPtr<mirror::ClassExt> ext(klass->GetExtData());
CHECK(ext.IsNull() || ext->GetVerifyError() == nullptr) << klass->PrettyClass();
}
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.
if (klass->IsResolved() && klass->NumReferenceStaticFields() != 0) {
size_t num_static_fields = klass->NumReferenceStaticFields();
// 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 {
mirror::Class* type = ref->GetClass();
result = result || PruneAppImageClassInternal(type,
&my_early_exit,
visited);
if (!result) {
// For non-class case, also go through all the types mentioned by it's fields'
// references recursively to decide whether to keep this class.
bool tmp = false;
PruneObjectReferenceVisitor visitor(this, &my_early_exit, visited, &tmp);
ref->VisitReferences(visitor, visitor);
result = result || tmp;
}
}
}
field_offset = MemberOffset(field_offset.Uint32Value() +
sizeof(mirror::HeapReference<mirror::Object>));
}
}
result = result || PruneAppImageClassInternal(klass->GetSuperClass(),
&my_early_exit,
visited);
// Remove the class if the dex file is not in the set of dex files. This happens for classes that
// are from uses-library if there is no profile. b/30688277
mirror::DexCache* dex_cache = klass->GetDexCache();
if (dex_cache != nullptr) {
result = result ||
dex_file_oat_index_map_.find(dex_cache->GetDexFile()) == dex_file_oat_index_map_.end();
}
// Erase the element we stored earlier since we are exiting the function.
auto it = visited->find(klass.Ptr());
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.Ptr()] = result;
}
*early_exit |= my_early_exit;
return result;
}
bool ImageWriter::KeepClass(ObjPtr<mirror::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_options_.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 ImageWriter::PruneClassesVisitor : public ClassVisitor {
public:
PruneClassesVisitor(ImageWriter* image_writer, ObjPtr<mirror::ClassLoader> class_loader)
: image_writer_(image_writer),
class_loader_(class_loader),
classes_to_prune_(),
defined_class_count_(0u) { }
bool operator()(ObjPtr<mirror::Class> klass) override REQUIRES_SHARED(Locks::mutator_lock_) {
if (!image_writer_->KeepClass(klass.Ptr())) {
classes_to_prune_.insert(klass.Ptr());
if (klass->GetClassLoader() == class_loader_) {
++defined_class_count_;
}
}
return true;
}
size_t Prune() REQUIRES_SHARED(Locks::mutator_lock_) {
ClassTable* class_table =
Runtime::Current()->GetClassLinker()->ClassTableForClassLoader(class_loader_);
for (mirror::Class* klass : classes_to_prune_) {
std::string storage;
const char* descriptor = klass->GetDescriptor(&storage);
bool result = class_table->Remove(descriptor);
DCHECK(result);
DCHECK(!class_table->Remove(descriptor)) << descriptor;
}
return defined_class_count_;
}
private:
ImageWriter* const image_writer_;
const ObjPtr<mirror::ClassLoader> class_loader_;
std::unordered_set<mirror::Class*> classes_to_prune_;
size_t defined_class_count_;
};
class ImageWriter::PruneClassLoaderClassesVisitor : public ClassLoaderVisitor {
public:
explicit PruneClassLoaderClassesVisitor(ImageWriter* image_writer)
: image_writer_(image_writer), removed_class_count_(0) {}
void Visit(ObjPtr<mirror::ClassLoader> class_loader) override
REQUIRES_SHARED(Locks::mutator_lock_) {
PruneClassesVisitor classes_visitor(image_writer_, class_loader);
ClassTable* class_table =
Runtime::Current()->GetClassLinker()->ClassTableForClassLoader(class_loader);
class_table->Visit(classes_visitor);
removed_class_count_ += classes_visitor.Prune();
// Record app image class loader. The fake boot class loader should not get registered
// and we should end up with only one class loader for an app and none for boot image.
if (class_loader != nullptr && class_table != nullptr) {
DCHECK(class_loader_ == nullptr);
class_loader_ = class_loader;
}
}
size_t GetRemovedClassCount() const {
return removed_class_count_;
}
ObjPtr<mirror::ClassLoader> GetClassLoader() const REQUIRES_SHARED(Locks::mutator_lock_) {
return class_loader_;
}
private:
ImageWriter* const image_writer_;
size_t removed_class_count_;
ObjPtr<mirror::ClassLoader> class_loader_;
};
void ImageWriter::VisitClassLoaders(ClassLoaderVisitor* visitor) {
WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_);
visitor->Visit(nullptr); // Visit boot class loader.
Runtime::Current()->GetClassLinker()->VisitClassLoaders(visitor);
}
void ImageWriter::PruneAndPreloadDexCache(ObjPtr<mirror::DexCache> dex_cache,
ObjPtr<mirror::ClassLoader> class_loader) {
// To ensure deterministic contents of the hash-based arrays, each slot shall contain
// the candidate with the lowest index. As we're processing entries in increasing index
// order, this means trying to look up the entry for the current index if the slot is
// empty or if it contains a higher index.
Runtime* runtime = Runtime::Current();
ClassLinker* class_linker = runtime->GetClassLinker();
const DexFile& dex_file = *dex_cache->GetDexFile();
// Prune methods.
mirror::MethodDexCacheType* resolved_methods = dex_cache->GetResolvedMethods();
dex::TypeIndex last_class_idx; // Initialized to invalid index.
ObjPtr<mirror::Class> last_class = nullptr;
for (size_t i = 0, num = dex_cache->GetDexFile()->NumMethodIds(); i != num; ++i) {
uint32_t slot_idx = dex_cache->MethodSlotIndex(i);
auto pair =
mirror::DexCache::GetNativePairPtrSize(resolved_methods, slot_idx, target_ptr_size_);
uint32_t stored_index = pair.index;
ArtMethod* method = pair.object;
if (method != nullptr && i > stored_index) {
continue; // Already checked.
}
// Check if the referenced class is in the image. Note that we want to check the referenced
// class rather than the declaring class to preserve the semantics, i.e. using a MethodId
// results in resolving the referenced class and that can for example throw OOME.
const DexFile::MethodId& method_id = dex_file.GetMethodId(i);
if (method_id.class_idx_ != last_class_idx) {
last_class_idx = method_id.class_idx_;
last_class = class_linker->LookupResolvedType(last_class_idx, dex_cache, class_loader);
if (last_class != nullptr && !KeepClass(last_class)) {
last_class = nullptr;
}
}
if (method == nullptr || i < stored_index) {
if (last_class != nullptr) {
// Try to resolve the method with the class linker, which will insert
// it into the dex cache if successful.
method = class_linker->FindResolvedMethod(last_class, dex_cache, class_loader, i);
// If the referenced class is in the image, the defining class must also be there.
DCHECK(method == nullptr || KeepClass(method->GetDeclaringClass()));
DCHECK(method == nullptr || dex_cache->GetResolvedMethod(i, target_ptr_size_) == method);
}
} else {
DCHECK_EQ(i, stored_index);
if (last_class == nullptr) {
dex_cache->ClearResolvedMethod(stored_index, target_ptr_size_);
}
}
}
// Prune fields and make the contents of the field array deterministic.
mirror::FieldDexCacheType* resolved_fields = dex_cache->GetResolvedFields();
last_class_idx = dex::TypeIndex(); // Initialized to invalid index.
last_class = nullptr;
for (size_t i = 0, end = dex_file.NumFieldIds(); i < end; ++i) {
uint32_t slot_idx = dex_cache->FieldSlotIndex(i);
auto pair = mirror::DexCache::GetNativePairPtrSize(resolved_fields, slot_idx, target_ptr_size_);
uint32_t stored_index = pair.index;
ArtField* field = pair.object;
if (field != nullptr && i > stored_index) {
continue; // Already checked.
}
// Check if the referenced class is in the image. Note that we want to check the referenced
// class rather than the declaring class to preserve the semantics, i.e. using a FieldId
// results in resolving the referenced class and that can for example throw OOME.
const DexFile::FieldId& field_id = dex_file.GetFieldId(i);
if (field_id.class_idx_ != last_class_idx) {
last_class_idx = field_id.class_idx_;
last_class = class_linker->LookupResolvedType(last_class_idx, dex_cache, class_loader);
if (last_class != nullptr && !KeepClass(last_class)) {
last_class = nullptr;
}
}
if (field == nullptr || i < stored_index) {
if (last_class != nullptr) {
field = class_linker->FindResolvedFieldJLS(last_class, dex_cache, class_loader, i);
// If the referenced class is in the image, the defining class must also be there.
DCHECK(field == nullptr || KeepClass(field->GetDeclaringClass()));
DCHECK(field == nullptr || dex_cache->GetResolvedField(i, target_ptr_size_) == field);
}
} else {
DCHECK_EQ(i, stored_index);
if (last_class == nullptr) {
dex_cache->ClearResolvedField(stored_index, target_ptr_size_);
}
}
}
// Prune types and make the contents of the type array deterministic.
// This is done after fields and methods as their lookup can touch the types array.
for (size_t i = 0, end = dex_cache->GetDexFile()->NumTypeIds(); i < end; ++i) {
dex::TypeIndex type_idx(i);
uint32_t slot_idx = dex_cache->TypeSlotIndex(type_idx);
mirror::TypeDexCachePair pair =
dex_cache->GetResolvedTypes()[slot_idx].load(std::memory_order_relaxed);
uint32_t stored_index = pair.index;
ObjPtr<mirror::Class> klass = pair.object.Read();
if (klass == nullptr || i < stored_index) {
klass = class_linker->LookupResolvedType(type_idx, dex_cache, class_loader);
if (klass != nullptr) {
DCHECK_EQ(dex_cache->GetResolvedType(type_idx), klass);
stored_index = i; // For correct clearing below if not keeping the `klass`.
}
} else if (i == stored_index && !KeepClass(klass)) {
dex_cache->ClearResolvedType(dex::TypeIndex(stored_index));
}
}
// Strings do not need pruning, but the contents of the string array must be deterministic.
for (size_t i = 0, end = dex_cache->GetDexFile()->NumStringIds(); i < end; ++i) {
dex::StringIndex string_idx(i);
uint32_t slot_idx = dex_cache->StringSlotIndex(string_idx);
mirror::StringDexCachePair pair =
dex_cache->GetStrings()[slot_idx].load(std::memory_order_relaxed);
uint32_t stored_index = pair.index;
ObjPtr<mirror::String> string = pair.object.Read();
if (string == nullptr || i < stored_index) {
string = class_linker->LookupString(string_idx, dex_cache);
DCHECK(string == nullptr || dex_cache->GetResolvedString(string_idx) == string);
}
}
}
void ImageWriter::PruneNonImageClasses() {
Runtime* runtime = Runtime::Current();
ClassLinker* class_linker = runtime->GetClassLinker();
Thread* self = Thread::Current();
ScopedAssertNoThreadSuspension sa(__FUNCTION__);
// Prune uses-library dex caches. Only prune the uses-library dex caches since we want to make
// sure the other ones don't get unloaded before the OatWriter runs.
class_linker->VisitClassTables(
[&](ClassTable* table) REQUIRES_SHARED(Locks::mutator_lock_) {
table->RemoveStrongRoots(
[&](GcRoot<mirror::Object> root) REQUIRES_SHARED(Locks::mutator_lock_) {
ObjPtr<mirror::Object> obj = root.Read();
if (obj->IsDexCache()) {
// Return true if the dex file is not one of the ones in the map.
return dex_file_oat_index_map_.find(obj->AsDexCache()->GetDexFile()) ==
dex_file_oat_index_map_.end();
}
// Return false to avoid removing.
return false;
});
});
// Remove the undesired classes from the class roots.
ObjPtr<mirror::ClassLoader> class_loader;
{
PruneClassLoaderClassesVisitor class_loader_visitor(this);
VisitClassLoaders(&class_loader_visitor);
VLOG(compiler) << "Pruned " << class_loader_visitor.GetRemovedClassCount() << " classes";
class_loader = class_loader_visitor.GetClassLoader();
DCHECK_EQ(class_loader != nullptr, compile_app_image_);
}
// Clear references to removed classes from the DexCaches.
std::vector<ObjPtr<mirror::DexCache>> dex_caches;
{
ReaderMutexLock mu2(self, *Locks::dex_lock_);
dex_caches.reserve(class_linker->GetDexCachesData().size());
for (const ClassLinker::DexCacheData& data : class_linker->GetDexCachesData()) {
if (self->IsJWeakCleared(data.weak_root)) {
continue;
}
dex_caches.push_back(self->DecodeJObject(data.weak_root)->AsDexCache());
}
}
for (ObjPtr<mirror::DexCache> dex_cache : dex_caches) {
// Pass the class loader associated with the DexCache. This can either be
// the app's `class_loader` or `nullptr` if boot class loader.
PruneAndPreloadDexCache(dex_cache, IsInBootImage(dex_cache.Ptr()) ? nullptr : class_loader);
}
// 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() {
auto visitor = [&](Object* obj) REQUIRES_SHARED(Locks::mutator_lock_) {
if (obj->IsClass() && !IsInBootImage(obj)) {
Class* klass = obj->AsClass();
if (!KeepClass(klass)) {
DumpImageClasses();
CHECK(KeepClass(klass))
<< Runtime::Current()->GetHeap()->GetVerification()->FirstPathFromRootSet(klass);
}
}
};
gc::Heap* heap = Runtime::Current()->GetHeap();
heap->VisitObjects(visitor);
}
void ImageWriter::DumpImageClasses() {
for (const std::string& image_class : compiler_options_.GetImageClasses()) {
LOG(INFO) << " " << image_class;
}
}
mirror::String* ImageWriter::FindInternedString(mirror::String* string) {
Thread* const self = Thread::Current();
for (const ImageInfo& image_info : image_infos_) {
ObjPtr<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.Ptr();
}
}
if (compile_app_image_) {
Runtime* const runtime = Runtime::Current();
ObjPtr<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.Ptr())) {
return found.Ptr();
}
DCHECK(runtime->GetInternTable()->LookupWeak(self, string) == nullptr)
<< string->ToModifiedUtf8();
}
return nullptr;
}
ObjPtr<mirror::ObjectArray<mirror::Object>> ImageWriter::CollectDexCaches(Thread* self,
size_t oat_index) const {
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.
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
size_t dex_cache_count = 0;
{
ReaderMutexLock mu(self, *Locks::dex_lock_);
// Count number of dex caches not in the boot image.
for (const ClassLinker::DexCacheData& data : class_linker->GetDexCachesData()) {
ObjPtr<mirror::DexCache> dex_cache =
ObjPtr<mirror::DexCache>::DownCast(self->DecodeJObject(data.weak_root));
if (dex_cache == nullptr) {
continue;
}
const DexFile* dex_file = dex_cache->GetDexFile();
if (!IsInBootImage(dex_cache.Ptr())) {
dex_cache_count += image_dex_files.find(dex_file) != image_dex_files.end() ? 1u : 0u;
}
}
}
ObjPtr<ObjectArray<Object>> dex_caches = ObjectArray<Object>::Alloc(
self, GetClassRoot<ObjectArray<Object>>(class_linker), dex_cache_count);
CHECK(dex_caches != nullptr) << "Failed to allocate a dex cache array.";
{
ReaderMutexLock mu(self, *Locks::dex_lock_);
size_t non_image_dex_caches = 0;
// Re-count number of non image dex caches.
for (const ClassLinker::DexCacheData& data : class_linker->GetDexCachesData()) {
ObjPtr<mirror::DexCache> dex_cache =
ObjPtr<mirror::DexCache>::DownCast(self->DecodeJObject(data.weak_root));
if (dex_cache == nullptr) {
continue;
}
const DexFile* dex_file = dex_cache->GetDexFile();
if (!IsInBootImage(dex_cache.Ptr())) {
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()) {
ObjPtr<mirror::DexCache> dex_cache =
ObjPtr<mirror::DexCache>::DownCast(self->DecodeJObject(data.weak_root));
if (dex_cache == nullptr) {
continue;
}
const DexFile* dex_file = dex_cache->GetDexFile();
if (!IsInBootImage(dex_cache.Ptr()) &&
image_dex_files.find(dex_file) != image_dex_files.end()) {
dex_caches->Set<false>(i, dex_cache.Ptr());
++i;
}
}
}
return dex_caches;
}
ObjPtr<ObjectArray<Object>> ImageWriter::CreateImageRoots(
size_t oat_index,
Handle<mirror::ObjectArray<mirror::Object>> boot_image_live_objects) const {
Runtime* runtime = Runtime::Current();
ClassLinker* class_linker = runtime->GetClassLinker();
Thread* self = Thread::Current();
StackHandleScope<2> hs(self);
Handle<ObjectArray<Object>> dex_caches(hs.NewHandle(CollectDexCaches(self, oat_index)));
// build an Object[] of the roots needed to restore the runtime
int32_t image_roots_size = ImageHeader::NumberOfImageRoots(compile_app_image_);
Handle<ObjectArray<Object>> image_roots(hs.NewHandle(ObjectArray<Object>::Alloc(
self, GetClassRoot<ObjectArray<Object>>(class_linker), image_roots_size)));
image_roots->Set<false>(ImageHeader::kDexCaches, dex_caches.Get());
image_roots->Set<false>(ImageHeader::kClassRoots, class_linker->GetClassRoots());
image_roots->Set<false>(ImageHeader::kOomeWhenThrowingException,
runtime->GetPreAllocatedOutOfMemoryErrorWhenThrowingException());
image_roots->Set<false>(ImageHeader::kOomeWhenThrowingOome,
runtime->GetPreAllocatedOutOfMemoryErrorWhenThrowingOOME());
image_roots->Set<false>(ImageHeader::kOomeWhenHandlingStackOverflow,
runtime->GetPreAllocatedOutOfMemoryErrorWhenHandlingStackOverflow());
image_roots->Set<false>(ImageHeader::kNoClassDefFoundError,
runtime->GetPreAllocatedNoClassDefFoundError());
if (!compile_app_image_) {
DCHECK(boot_image_live_objects != nullptr);
image_roots->Set<false>(ImageHeader::kBootImageLiveObjects, boot_image_live_objects.Get());
} else {
DCHECK(boot_image_live_objects == nullptr);
}
for (int32_t i = 0, num = ImageHeader::NumberOfImageRoots(compile_app_image_); i != num; ++i) {
if (compile_app_image_ && i == ImageHeader::kAppImageClassLoader) {
// image_roots[ImageHeader::kAppImageClassLoader] will be set later for app image.
continue;
}
CHECK(image_roots->Get(i) != nullptr);
}
return image_roots.Get();
}
mirror::Object* ImageWriter::TryAssignBinSlot(WorkStack& work_stack,
mirror::Object* obj,
size_t oat_index) {
if (obj == nullptr || IsInBootImage(obj)) {
// Object is null or already in the image, there is no work to do.
return obj;
}
if (!IsImageBinSlotAssigned(obj)) {
// We want to intern all strings but also assign offsets for the source string. Since the
// pruning phase has already happened, if we intern a string to one in the image we still
// end up copying an unreachable string.
if (obj->IsString()) {
// 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 =
GetImageInfo(oat_index).intern_table_->InternStrongImageString(obj->AsString()).Ptr();
DCHECK_EQ(interned, obj);
}
} else if (obj->IsDexCache()) {
oat_index = GetOatIndexForDexCache(obj->AsDexCache());
} else if (obj->IsClass()) {
// Visit and assign offsets for fields and field arrays.
mirror::Class* as_klass = obj->AsClass();
mirror::DexCache* dex_cache = as_klass->GetDexCache();
DCHECK(!as_klass->IsErroneous()) << as_klass->GetStatus();
if (compile_app_image_) {
// Extra sanity, no boot loader classes should be left!
CHECK(!IsBootClassLoaderClass(as_klass)) << as_klass->PrettyClass();
}
LengthPrefixedArray<ArtField>* fields[] = {
as_klass->GetSFieldsPtr(), as_klass->GetIFieldsPtr(),
};
// Overwrite the oat index value since the class' dex cache is more accurate of where it
// belongs.
oat_index = GetOatIndexForDexCache(dex_cache);
ImageInfo& image_info = GetImageInfo(oat_index);
if (!compile_app_image_) {
// Note: Avoid locking to prevent lock order violations from root visiting;
// image_info.class_table_ is only accessed from the image writer.
image_info.class_table_->InsertWithoutLocks(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.GetBinSlotSize(Bin::kArtField);
DCHECK(!IsInBootImage(cur_fields));
native_object_relocations_.emplace(
cur_fields,
NativeObjectRelocation {
oat_index, offset, NativeObjectRelocationType::kArtFieldArray
});
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 " << field->PrettyField() << " static=" << field->IsStatic();
DCHECK(!IsInBootImage(field));
native_object_relocations_.emplace(
field,
NativeObjectRelocation { oat_index,
offset,
NativeObjectRelocationType::kArtField });
offset += sizeof(ArtField);
}
image_info.IncrementBinSlotSize(
Bin::kArtField, header_size + cur_fields->size() * sizeof(ArtField));
DCHECK_EQ(offset, image_info.GetBinSlotSize(Bin::kArtField));
}
}
// 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
? NativeObjectRelocationType::kArtMethodDirty
: NativeObjectRelocationType::kArtMethodClean;
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.GetBinSlotSize(bin_type);
DCHECK(!IsInBootImage(array));
native_object_relocations_.emplace(array,
NativeObjectRelocation {
oat_index,
offset,
any_dirty ? NativeObjectRelocationType::kArtMethodArrayDirty
: NativeObjectRelocationType::kArtMethodArrayClean });
image_info.IncrementBinSlotSize(bin_type, header_size);
for (auto& m : as_klass->GetMethods(target_ptr_size_)) {
AssignMethodOffset(&m, type, oat_index);
}
(any_dirty ? dirty_methods_ : clean_methods_) += num_methods;
}
// Assign offsets for all runtime methods in the IMT since these may hold conflict tables
// live.
if (as_klass->ShouldHaveImt()) {
ImTable* imt = as_klass->GetImt(target_ptr_size_);
if (TryAssignImTableOffset(imt, oat_index)) {
// Since imt's can be shared only do this the first time to not double count imt method
// fixups.
for (size_t i = 0; i < ImTable::kSize; ++i) {
ArtMethod* imt_method = imt->Get(i, target_ptr_size_);
DCHECK(imt_method != nullptr);
if (imt_method->IsRuntimeMethod() &&
!IsInBootImage(imt_method) &&
!NativeRelocationAssigned(imt_method)) {
AssignMethodOffset(imt_method, NativeObjectRelocationType::kRuntimeMethod, oat_index);
}
}
}
}
} else if (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 = obj->AsClassLoader();
if (class_loader->GetClassTable() != nullptr) {
DCHECK(compile_app_image_);
DCHECK(class_loaders_.empty());
class_loaders_.insert(class_loader);
ImageInfo& image_info = GetImageInfo(oat_index);
// Note: Avoid locking to prevent lock order violations from root visiting;
// image_info.class_table_ table is only accessed from the image writer
// and class_loader->GetClassTable() is iterated but not modified.
image_info.class_table_->CopyWithoutLocks(*class_loader->GetClassTable());
}
}
AssignImageBinSlot(obj, oat_index);
work_stack.emplace(obj, oat_index);
}
if (obj->IsString()) {
// Always return the interned string if there exists one.
mirror::String* interned = FindInternedString(obj->AsString());
if (interned != nullptr) {
return interned;
}
}
return obj;
}
bool ImageWriter::NativeRelocationAssigned(void* ptr) const {
return native_object_relocations_.find(ptr) != native_object_relocations_.end();
}
bool ImageWriter::TryAssignImTableOffset(ImTable* imt, size_t oat_index) {
// No offset, or already assigned.
if (imt == nullptr || IsInBootImage(imt) || NativeRelocationAssigned(imt)) {
return false;
}
// If the method is a conflict method we also want to assign the conflict table offset.
ImageInfo& image_info = GetImageInfo(oat_index);
const size_t size = ImTable::SizeInBytes(target_ptr_size_);
native_object_relocations_.emplace(
imt,
NativeObjectRelocation {
oat_index,
image_info.GetBinSlotSize(Bin::kImTable),
NativeObjectRelocationType::kIMTable});
image_info.IncrementBinSlotSize(Bin::kImTable, size);
return true;
}
void ImageWriter::TryAssignConflictTableOffset(ImtConflictTable* table, size_t oat_index) {
// No offset, or already assigned.
if (table == nullptr || NativeRelocationAssigned(table)) {
return;
}
CHECK(!IsInBootImage(table));
// If the method is a conflict method we also want to assign the conflict table offset.
ImageInfo& image_info = GetImageInfo(oat_index);
const size_t size = table->ComputeSize(target_ptr_size_);
native_object_relocations_.emplace(
table,
NativeObjectRelocation {
oat_index,
image_info.GetBinSlotSize(Bin::kIMTConflictTable),
NativeObjectRelocationType::kIMTConflictTable});
image_info.IncrementBinSlotSize(Bin::kIMTConflictTable, size);
}
void ImageWriter::AssignMethodOffset(ArtMethod* method,
NativeObjectRelocationType type,
size_t oat_index) {
DCHECK(!IsInBootImage(method));
CHECK(!NativeRelocationAssigned(method)) << "Method " << method << " already assigned "
<< ArtMethod::PrettyMethod(method);
if (method->IsRuntimeMethod()) {
TryAssignConflictTableOffset(method->GetImtConflictTable(target_ptr_size_), oat_index);
}
ImageInfo& image_info = GetImageInfo(oat_index);
Bin bin_type = BinTypeForNativeRelocationType(type);
size_t offset = image_info.GetBinSlotSize(bin_type);
native_object_relocations_.emplace(method, NativeObjectRelocation { oat_index, offset, type });
image_info.IncrementBinSlotSize(bin_type, ArtMethod::Size(target_ptr_size_));
}
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);
}
class ImageWriter::VisitReferencesVisitor {
public:
VisitReferencesVisitor(ImageWriter* image_writer, WorkStack* work_stack, size_t oat_index)
: image_writer_(image_writer), work_stack_(work_stack), oat_index_(oat_index) {}
// Fix up separately since we also need to fix up method entrypoints.
ALWAYS_INLINE void VisitRootIfNonNull(mirror::CompressedReference<mirror::Object>* root) const
REQUIRES_SHARED(Locks::mutator_lock_) {
if (!root->IsNull()) {
VisitRoot(root);
}
}
ALWAYS_INLINE void VisitRoot(mirror::CompressedReference<mirror::Object>* root) const
REQUIRES_SHARED(Locks::mutator_lock_) {
root->Assign(VisitReference(root->AsMirrorPtr()));
}
ALWAYS_INLINE void operator() (ObjPtr<mirror::Object> obj,
MemberOffset offset,
bool is_static ATTRIBUTE_UNUSED) const
REQUIRES_SHARED(Locks::mutator_lock_) {
mirror::Object* ref =
obj->GetFieldObject<mirror::Object, kVerifyNone, kWithoutReadBarrier>(offset);
obj->SetFieldObject</*kTransactionActive*/false>(offset, VisitReference(ref));
}
ALWAYS_INLINE 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:
mirror::Object* VisitReference(mirror::Object* ref) const REQUIRES_SHARED(Locks::mutator_lock_) {
return image_writer_->TryAssignBinSlot(*work_stack_, ref, oat_index_);
}
ImageWriter* const image_writer_;
WorkStack* const work_stack_;
const size_t oat_index_;
};
class ImageWriter::GetRootsVisitor : public RootVisitor {
public:
explicit GetRootsVisitor(std::vector<mirror::Object*>* roots) : roots_(roots) {}
void VisitRoots(mirror::Object*** roots,
size_t count,
const RootInfo& info ATTRIBUTE_UNUSED) override
REQUIRES_SHARED(Locks::mutator_lock_) {
for (size_t i = 0; i < count; ++i) {
roots_->push_back(*roots[i]);
}
}
void VisitRoots(mirror::CompressedReference<mirror::Object>** roots,
size_t count,
const RootInfo& info ATTRIBUTE_UNUSED) override
REQUIRES_SHARED(Locks::mutator_lock_) {
for (size_t i = 0; i < count; ++i) {
roots_->push_back(roots[i]->AsMirrorPtr());
}
}
private:
std::vector<mirror::Object*>* const roots_;
};
void ImageWriter::ProcessWorkStack(WorkStack* work_stack) {
while (!work_stack->empty()) {
std::pair<mirror::Object*, size_t> pair(work_stack->top());
work_stack->pop();
VisitReferencesVisitor visitor(this, work_stack, /*oat_index*/ pair.second);
// Walk references and assign bin slots for them.
pair.first->VisitReferences</*kVisitNativeRoots*/true, kVerifyNone, kWithoutReadBarrier>(
visitor,
visitor);
}
}
void ImageWriter::CalculateNewObjectOffsets() {
Thread* const self = Thread::Current();
Runtime* const runtime = Runtime::Current();
VariableSizedHandleScope handles(self);
MutableHandle<ObjectArray<Object>> boot_image_live_objects = handles.NewHandle(
compile_app_image_
? nullptr
: IntrinsicObjects::AllocateBootImageLiveObjects(self, runtime->GetClassLinker()));
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, boot_image_live_objects)));
}
gc::Heap* const 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
const size_t method_alignment = ArtMethod::Alignment(target_ptr_size_);
// 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::kSaveAllCalleeSavesMethod] =
runtime->GetCalleeSaveMethod(CalleeSaveType::kSaveAllCalleeSaves);
image_methods_[ImageHeader::kSaveRefsOnlyMethod] =
runtime->GetCalleeSaveMethod(CalleeSaveType::kSaveRefsOnly);
image_methods_[ImageHeader::kSaveRefsAndArgsMethod] =
runtime->GetCalleeSaveMethod(CalleeSaveType::kSaveRefsAndArgs);
image_methods_[ImageHeader::kSaveEverythingMethod] =
runtime->GetCalleeSaveMethod(CalleeSaveType::kSaveEverything);
image_methods_[ImageHeader::kSaveEverythingMethodForClinit] =
runtime->GetCalleeSaveMethod(CalleeSaveType::kSaveEverythingForClinit);
image_methods_[ImageHeader::kSaveEverythingMethodForSuspendCheck] =
runtime->GetCalleeSaveMethod(CalleeSaveType::kSaveEverythingForSuspendCheck);
// Visit image methods first to have the main runtime methods in the first image.
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, NativeObjectRelocationType::kRuntimeMethod, GetDefaultOatIndex());
}
}
// Deflate monitors before we visit roots since deflating acquires the monitor lock. Acquiring
// this lock while holding other locks may cause lock order violations.
{
auto deflate_monitor = [](mirror::Object* obj) REQUIRES_SHARED(Locks::mutator_lock_) {
Monitor::Deflate(Thread::Current(), obj);
};
heap->VisitObjects(deflate_monitor);
}
// From this point on, there shall be no GC anymore and no objects shall be allocated.
// We can now assign a BitSlot to each object and store it in its lockword.
// Work list of <object, oat_index> for objects. Everything on the stack must already be
// assigned a bin slot.
WorkStack work_stack;
// Special case interned strings to put them in the image they are likely to be resolved from.
for (const DexFile* dex_file : compiler_options_.GetDexFilesForOatFile()) {
auto it = dex_file_oat_index_map_.find(dex_file);
DCHECK(it != dex_file_oat_index_map_.end()) << dex_file->GetLocation();
const size_t oat_index = it->second;
InternTable* const intern_table = runtime->GetInternTable();
for (size_t i = 0, count = dex_file->NumStringIds(); i < count; ++i) {
uint32_t utf16_length;
const char* utf8_data = dex_file->StringDataAndUtf16LengthByIdx(dex::StringIndex(i),
&utf16_length);
mirror::String* string = intern_table->LookupStrong(self, utf16_length, utf8_data).Ptr();
TryAssignBinSlot(work_stack, string, oat_index);
}
}
// Get the GC roots and then visit them separately to avoid lock violations since the root visitor
// visits roots while holding various locks.
{
std::vector<mirror::Object*> roots;
GetRootsVisitor root_visitor(&roots);
runtime->VisitRoots(&root_visitor);
for (mirror::Object* obj : roots) {
TryAssignBinSlot(work_stack, obj, GetDefaultOatIndex());
}
}
ProcessWorkStack(&work_stack);
// For app images, there may be objects that are only held live by the boot image. One
// example is finalizer references. Forward these objects so that EnsureBinSlotAssignedCallback
// does not fail any checks.
if (compile_app_image_) {
for (gc::space::ImageSpace* space : heap->GetBootImageSpaces()) {
DCHECK(space->IsImageSpace());
gc::accounting::ContinuousSpaceBitmap* live_bitmap = space->GetLiveBitmap();
live_bitmap->VisitMarkedRange(reinterpret_cast<uintptr_t>(space->Begin()),
reinterpret_cast<uintptr_t>(space->Limit()),
[this, &work_stack](mirror::Object* obj)
REQUIRES_SHARED(Locks::mutator_lock_) {
VisitReferencesVisitor visitor(this, &work_stack, GetDefaultOatIndex());
// Visit all references and try to assign bin slots for them (calls TryAssignBinSlot).
obj->VisitReferences</*kVisitNativeRoots*/true, kVerifyNone, kWithoutReadBarrier>(
visitor,
visitor);
});
}
// Process the work stack in case anything was added by TryAssignBinSlot.
ProcessWorkStack(&work_stack);
// Store the class loader in the class roots.
CHECK_EQ(class_loaders_.size(), 1u);
CHECK_EQ(image_roots.size(), 1u);
CHECK(*class_loaders_.begin() != nullptr);
image_roots[0]->Set<false>(ImageHeader::kAppImageClassLoader, *class_loaders_.begin());
}
// Verify that all objects have assigned image bin slots.
{
auto ensure_bin_slots_assigned = [&](mirror::Object* obj)
REQUIRES_SHARED(Locks::mutator_lock_) {
if (!Runtime::Current()->GetHeap()->ObjectIsInBootImageSpace(obj)) {
CHECK(IsImageBinSlotAssigned(obj)) << mirror::Object::PrettyTypeOf(obj) << " " << obj;
}
};
heap->VisitObjects(ensure_bin_slots_assigned);
}
// Calculate size of the dex cache arrays slot and prepare offsets.
PrepareDexCacheArraySlots();
// Calculate the sizes of the intern tables, class tables, and fixup 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";
if (intern_table->StrongSize() != 0u) {
image_info.intern_table_bytes_ = intern_table->WriteToMemory(nullptr);
}
// Calculate the size of the class table.
ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_);
DCHECK_EQ(image_info.class_table_->NumReferencedZygoteClasses(), 0u);
if (image_info.class_table_->NumReferencedNonZygoteClasses() != 0u) {
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 != kNumberOfBins; ++i) {
switch (static_cast<Bin>(i)) {
case Bin::kArtMethodClean:
case Bin::kArtMethodDirty: {
bin_offset = RoundUp(bin_offset, method_alignment);
break;
}
case Bin::kDexCacheArray:
bin_offset = RoundUp(bin_offset, DexCacheArraysLayout::Alignment(target_ptr_size_));
break;
case Bin::kImTable:
case Bin::kIMTConflictTable: {
bin_offset = RoundUp(bin_offset, static_cast<size_t>(target_ptr_size_));
break;
}
default: {
// Normal alignment.
}
}
image_info.bin_slot_offsets_[i] = bin_offset;
bin_offset += image_info.bin_slot_sizes_[i];
}
// NOTE: There may be additional padding between the bin slots and the intern table.
DCHECK_EQ(image_info.image_end_,
image_info.GetBinSizeSum(Bin::kMirrorCount) + 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;
image_info.image_size_ = RoundUp(image_info.CreateImageSections().first, 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.
{
auto unbin_objects_into_offset = [&](mirror::Object* obj)
REQUIRES_SHARED(Locks::mutator_lock_) {
if (!IsInBootImage(obj)) {
UnbinObjectsIntoOffset(obj);
}
};
heap->VisitObjects(unbin_objects_into_offset);
}
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.GetBinSlotOffset(bin_type);
}
// Remember the boot image live objects as raw pointer. No GC can happen anymore.
boot_image_live_objects_ = boot_image_live_objects.Get();
}
std::pair<size_t, std::vector<ImageSection>> ImageWriter::ImageInfo::CreateImageSections() const {
std::vector<ImageSection> sections(ImageHeader::kSectionCount);
// Do not round up any sections here that are represented by the bins since it
// will break offsets.
/*
* Objects section
*/
sections[ImageHeader::kSectionObjects] =
ImageSection(0u, image_end_);
/*
* Field section
*/
sections[ImageHeader::kSectionArtFields] =
ImageSection(GetBinSlotOffset(Bin::kArtField), GetBinSlotSize(Bin::kArtField));
/*
* Method section
*/
sections[ImageHeader::kSectionArtMethods] =
ImageSection(GetBinSlotOffset(Bin::kArtMethodClean),
GetBinSlotSize(Bin::kArtMethodClean) +
GetBinSlotSize(Bin::kArtMethodDirty));
/*
* IMT section
*/
sections[ImageHeader::kSectionImTables] =
ImageSection(GetBinSlotOffset(Bin::kImTable), GetBinSlotSize(Bin::kImTable));
/*
* Conflict Tables section
*/
sections[ImageHeader::kSectionIMTConflictTables] =
ImageSection(GetBinSlotOffset(Bin::kIMTConflictTable), GetBinSlotSize(Bin::kIMTConflictTable));
/*
* Runtime Methods section
*/
sections[ImageHeader::kSectionRuntimeMethods] =
ImageSection(GetBinSlotOffset(Bin::kRuntimeMethod), GetBinSlotSize(Bin::kRuntimeMethod));
/*
* DexCache Arrays section.
*/
const ImageSection& dex_cache_arrays_section =
sections[ImageHeader::kSectionDexCacheArrays] =
ImageSection(GetBinSlotOffset(Bin::kDexCacheArray),
GetBinSlotSize(Bin::kDexCacheArray));
/*
* Interned Strings section
*/
// Round up to the alignment the string table expects. See HashSet::WriteToMemory.
size_t cur_pos = RoundUp(dex_cache_arrays_section.End(), sizeof(uint64_t));
const ImageSection& interned_strings_section =
sections[ImageHeader::kSectionInternedStrings] =
ImageSection(cur_pos, intern_table_bytes_);
/*
* Class Table section
*/
// Obtain the new position and round it up to the appropriate alignment.
cur_pos = RoundUp(interned_strings_section.End(), sizeof(uint64_t));
const ImageSection& class_table_section =
sections[ImageHeader::kSectionClassTable] =
ImageSection(cur_pos, class_table_bytes_);
/*
* String Field Offsets section
*/
// Round up to the alignment of the offsets we are going to store.
cur_pos = RoundUp(class_table_section.End(), sizeof(uint32_t));
const ImageSection& string_reference_offsets =
sections[ImageHeader::kSectionStringReferenceOffsets] =
ImageSection(cur_pos, sizeof(uint32_t) * num_string_references_);
// Return the number of bytes described by these sections, and the sections
// themselves.
return make_pair(string_reference_offsets.End(), std::move(sections));
}
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.
auto section_info_pair = image_info.CreateImageSections();
const size_t image_end = section_info_pair.first;
std::vector<ImageSection>& sections = section_info_pair.second;
// 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));
// The relocations section shall be finished later as we do not know its actual size yet.
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.
ImageHeader* header = new (image_info.image_.Begin()) ImageHeader(
PointerToLowMemUInt32(image_info.image_begin_),
image_end,
sections.data(),
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,
static_cast<uint32_t>(target_ptr_size_),
compile_pic_,
/*is_pic*/compile_app_image_,
image_storage_mode_,
/*data_size*/0u);
// Resize relocation bitmap for recording reference/pointer relocations.
size_t number_of_relocation_locations = RelocationIndex(image_end, target_ptr_size_);
DCHECK(image_info.relocation_bitmap_.empty());
image_info.relocation_bitmap_.resize(
BitsToBytesRoundUp(number_of_relocation_locations * (compile_app_image_ ? 2u : 1u)));
// Record header relocations.
RecordImageRelocation(&header->image_begin_, oat_index);
RecordImageRelocation(&header->oat_file_begin_, oat_index);
RecordImageRelocation(&header->oat_data_begin_, oat_index);
RecordImageRelocation(&header->oat_data_end_, oat_index);
RecordImageRelocation(&header->oat_file_end_, oat_index);
if (compile_app_image_) {
RecordImageRelocation(&header->boot_image_begin_, oat_index, /* app_to_boot_image */ true);
RecordImageRelocation(&header->boot_oat_begin_, oat_index, /* app_to_boot_image */ true);
} else {
DCHECK_EQ(header->boot_image_begin_, 0u);
DCHECK_EQ(header->boot_oat_begin_, 0u);
}
RecordImageRelocation(&header->image_roots_, oat_index);
// Skip non-null check for `patch_delta_` as it is actually 0 but still needs to be recorded.
RecordImageRelocation</* kCheckNotNull */ false>(&header->patch_delta_, oat_index);
}
ArtMethod* ImageWriter::GetImageMethodAddress(ArtMethod* method) {
NativeObjectRelocation relocation = GetNativeRelocation(method);
const ImageInfo& image_info = GetImageInfo(relocation.oat_index);
CHECK_GE(relocation.offset, image_info.image_end_) << "ArtMethods should be after Objects";
return reinterpret_cast<ArtMethod*>(image_info.image_begin_ + relocation.offset);
}
const void* ImageWriter::GetIntrinsicReferenceAddress(uint32_t intrinsic_data) {
DCHECK(!compile_app_image_);
switch (IntrinsicObjects::DecodePatchType(intrinsic_data)) {
case IntrinsicObjects::PatchType::kIntegerValueOfArray: {
const uint8_t* base_address =
reinterpret_cast<const uint8_t*>(GetImageAddress(boot_image_live_objects_));
MemberOffset data_offset =
IntrinsicObjects::GetIntegerValueOfArrayDataOffset(boot_image_live_objects_);
return base_address + data_offset.Uint32Value();
}
case IntrinsicObjects::PatchType::kIntegerValueOfObject: {
uint32_t index = IntrinsicObjects::DecodePatchIndex(intrinsic_data);
ObjPtr<mirror::Object> value =
IntrinsicObjects::GetIntegerValueOfObject(boot_image_live_objects_, index);
return GetImageAddress(value.Ptr());
}
}
LOG(FATAL) << "UNREACHABLE";
UNREACHABLE();
}
class ImageWriter::FixupRootVisitor : public RootVisitor {
public:
explicit FixupRootVisitor(ImageWriter* image_writer) : image_writer_(image_writer) {
}
void VisitRoots(mirror::Object*** roots ATTRIBUTE_UNUSED,
size_t count ATTRIBUTE_UNUSED,
const RootInfo& info ATTRIBUTE_UNUSED)
override REQUIRES_SHARED(Locks::mutator_lock_) {
LOG(FATAL) << "Unsupported";
}
void VisitRoots(mirror::CompressedReference<mirror::Object>** roots,
size_t count,
const RootInfo& info ATTRIBUTE_UNUSED)
override REQUIRES_SHARED(Locks::mutator_lock_) {
for (size_t i = 0; i < count; ++i) {
// Copy the reference. Since we do not have the address for recording the relocation,
// it needs to be recorded explicitly by the user of FixupRootVisitor.
ObjPtr<mirror::Object> old_ptr = roots[i]->AsMirrorPtr();
roots[i]->Assign(image_writer_->GetImageAddress(old_ptr.Ptr()));
}
}
private:
ImageWriter* const image_writer_;
};
void ImageWriter::CopyAndFixupImTable(ImTable* orig, ImTable* copy, size_t oat_index) {
for (size_t i = 0; i < ImTable::kSize; ++i) {
ArtMethod* method = orig->Get(i, target_ptr_size_);
void** address = reinterpret_cast<void**>(copy->AddressOfElement(i, target_ptr_size_));
CopyAndFixupPointer(address, method, oat_index);
DCHECK_EQ(copy->Get(i, target_ptr_size_), NativeLocationInImage(method));
}
}
void ImageWriter::CopyAndFixupImtConflictTable(ImtConflictTable* orig,
ImtConflictTable* copy,
size_t oat_index) {
const size_t count = orig->NumEntries(target_ptr_size_);
for (size_t i = 0; i < count; ++i) {
ArtMethod* interface_method = orig->GetInterfaceMethod(i, target_ptr_size_);
ArtMethod* implementation_method = orig->GetImplementationMethod(i, target_ptr_size_);
CopyAndFixupPointer(copy->AddressOfInterfaceMethod(i, target_ptr_size_),
interface_method,
oat_index);
CopyAndFixupPointer(copy->AddressOfImplementationMethod(i, target_ptr_size_),
implementation_method,
oat_index);
DCHECK_EQ(copy->GetInterfaceMethod(i, target_ptr_size_),
NativeLocationInImage(interface_method));
DCHECK_EQ(copy->GetImplementationMethod(i, target_ptr_size_),
NativeLocationInImage(implementation_method));
}
}
void ImageWriter::CopyAndFixupNativeData(size_t oat_index) {
const 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 NativeObjectRelocationType::kArtField: {
memcpy(dest, pair.first, sizeof(ArtField));
CopyAndFixupReference(
reinterpret_cast<ArtField*>(dest)->GetDeclaringClassAddressWithoutBarrier(),
reinterpret_cast<ArtField*>(pair.first)->GetDeclaringClass(),
oat_index);
break;
}
case NativeObjectRelocationType::kRuntimeMethod:
case NativeObjectRelocationType::kArtMethodClean:
case NativeObjectRelocationType::kArtMethodDirty: {
CopyAndFixupMethod(reinterpret_cast<ArtMethod*>(pair.first),
reinterpret_cast<ArtMethod*>(dest),
oat_index);
break;
}
// For arrays, copy just the header since the elements will get copied by their corresponding
// relocations.
case NativeObjectRelocationType::kArtFieldArray: {
memcpy(dest, pair.first, LengthPrefixedArray<ArtField>::ComputeSize(0));
break;
}
case NativeObjectRelocationType::kArtMethodArrayClean:
case NativeObjectRelocationType::kArtMethodArrayDirty: {
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.
// Historical note: We also did that to placate Valgrind.
reinterpret_cast<LengthPrefixedArray<ArtMethod>*>(dest)->ClearPadding(size, alignment);
break;
}
case NativeObjectRelocationType::kDexCacheArray:
// Nothing to copy here, everything is done in FixupDexCache().
break;
case NativeObjectRelocationType::kIMTable: {
ImTable* orig_imt = reinterpret_cast<ImTable*>(pair.first);
ImTable* dest_imt = reinterpret_cast<ImTable*>(dest);
CopyAndFixupImTable(orig_imt, dest_imt, oat_index);
break;
}
case NativeObjectRelocationType::kIMTConflictTable: {
auto* orig_table = reinterpret_cast<ImtConflictTable*>(pair.first);
CopyAndFixupImtConflictTable(
orig_table,
new(dest)ImtConflictTable(orig_table->NumEntries(target_ptr_size_), target_ptr_size_),
oat_index);
break;
}
}
}
// Fixup the image method roots.
auto* image_header = reinterpret_cast<ImageHeader*>(image_info.image_.Begin());
for (size_t i = 0; i < ImageHeader::kImageMethodsCount; ++i) {
ArtMethod* method = image_methods_[i];
CHECK(method != nullptr);
CopyAndFixupPointer(reinterpret_cast<void**>(&image_header->image_methods_[i]),
method,
oat_index,
PointerSize::k32);
}
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->GetInternedStringsSection();
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);
// Record relocations. (The root visitor does not get to see the slot addresses.)
MutexLock lock(Thread::Current(), *Locks::intern_table_lock_);
DCHECK(!temp_intern_table.strong_interns_.tables_.empty());
DCHECK(!temp_intern_table.strong_interns_.tables_[0].empty()); // Inserted at the beginning.
for (const GcRoot<mirror::String>& slot : temp_intern_table.strong_interns_.tables_[0]) {
RecordImageRelocation(&slot, oat_index);
}
}
// 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->GetClassTableSection();
uint8_t* const class_table_memory_ptr =
image_info.image_.Begin() + class_table_section.Offset();
Thread* self = Thread::Current();
ReaderMutexLock mu(self, *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.NumReferencedZygoteClasses(),
table->NumReferencedNonZygoteClasses() + table->NumReferencedZygoteClasses());
UnbufferedRootVisitor visitor(&root_visitor, RootInfo(kRootUnknown));
temp_class_table.VisitRoots(visitor);
// Record relocations. (The root visitor does not get to see the slot addresses.)
// Note that the low bits in the slots contain bits of the descriptors' hash codes
// but the relocation works fine for these "adjusted" references.
ReaderMutexLock lock(self, temp_class_table.lock_);
DCHECK(!temp_class_table.classes_.empty());
DCHECK(!temp_class_table.classes_[0].empty()); // The ClassSet was inserted at the beginning.
for (const ClassTable::TableSlot& slot : temp_class_table.classes_[0]) {
RecordImageRelocation(&slot, oat_index);
}
}
}
void ImageWriter::CopyAndFixupObjects() {
auto visitor = [&](Object* obj) REQUIRES_SHARED(Locks::mutator_lock_) {
DCHECK(obj != nullptr);
CopyAndFixupObject(obj);
};
Runtime::Current()->GetHeap()->VisitObjects(visitor);
// We no longer need the hashcode map, values have already been copied to target objects.
saved_hashcode_map_.clear();
}
void ImageWriter::FixupPointerArray(mirror::Object* dst,
mirror::PointerArray* arr,
mirror::Class* klass,
Bin array_type,
size_t oat_index) {
CHECK(klass->IsArrayClass());
CHECK(arr->IsIntArray() || arr->IsLongArray()) << klass->PrettyClass() << " " << arr;
// Fixup int and long pointers for the ArtMethod or ArtField arrays.
const size_t num_elements = arr->GetLength();
CopyAndFixupReference(dst->GetFieldObjectReferenceAddr<kVerifyNone>(Class::ClassOffset()),
arr->GetClass(),
oat_index);
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 (kIsDebugBuild && 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 " << method->PrettyMethod() << " @ "
<< method << " idx=" << i << "/" << num_elements << " with declaring class "
<< Class::PrettyClass(method->GetDeclaringClass());
} else {
CHECK_EQ(array_type, Bin::kArtField);
auto* field = reinterpret_cast<ArtField*>(elem);
LOG(FATAL) << "No relocation entry for ArtField " << field->PrettyField() << " @ "
<< field << " idx=" << i << "/" << num_elements << " with declaring class "
<< Class::PrettyClass(field->GetDeclaringClass());
}
UNREACHABLE();
}
}
CopyAndFixupPointer(dest_array->ElementAddress(i, target_ptr_size_), elem, oat_index);
}
}
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);
if (kUseBakerReadBarrier && gc::collector::ConcurrentCopying::kGrayDirtyImmuneObjects) {
// Treat all of the objects in the image as marked to avoid unnecessary dirty pages. This is
// safe since we mark all of the objects that may reference non immune objects as gray.
CHECK(dst->AtomicSetMarkBit(0, 1));
}
FixupObject(obj, dst, oat_index);
}
// Rewrite all the references in the copied object to point to their image address equivalent
class ImageWriter::FixupVisitor {
public:
FixupVisitor(ImageWriter* image_writer, Object* copy, size_t oat_index)
: image_writer_(image_writer), copy_(copy), oat_index_(oat_index) {
}
// 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()(ObjPtr<Object> obj, MemberOffset offset, bool is_static ATTRIBUTE_UNUSED) const
REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(Locks::heap_bitmap_lock_) {
ObjPtr<Object> ref = obj->GetFieldObject<Object, kVerifyNone>(offset);
// Copy the reference and record the fixup if necessary.
image_writer_->CopyAndFixupReference(
copy_->GetFieldObjectReferenceAddr<kVerifyNone>(offset),
ref.Ptr(),
oat_index_);
}
// java.lang.ref.Reference visitor.
void operator()(ObjPtr<mirror::Class> klass ATTRIBUTE_UNUSED,
ObjPtr<mirror::Reference> ref) const
REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(Locks::heap_bitmap_lock_) {
operator()(ref, mirror::Reference::ReferentOffset(), /* is_static */ false);
}
protected:
ImageWriter* const image_writer_;
mirror::Object* const copy_;
size_t oat_index_;
};
class ImageWriter::FixupClassVisitor final : public FixupVisitor {
public:
FixupClassVisitor(ImageWriter* image_writer, Object* copy, size_t oat_index)
: FixupVisitor(image_writer, copy, oat_index) {}
void operator()(ObjPtr<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()(ObjPtr<mirror::Class> klass ATTRIBUTE_UNUSED,
ObjPtr<mirror::Reference> ref ATTRIBUTE_UNUSED) const
REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(Locks::heap_bitmap_lock_) {
LOG(FATAL) << "Reference not expected here.";
}
};
ImageWriter::NativeObjectRelocation ImageWriter::GetNativeRelocation(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();
return it->second;
}
template <typename T>
std::string PrettyPrint(T* ptr) REQUIRES_SHARED(Locks::mutator_lock_) {
std::ostringstream oss;
oss << ptr;
return oss.str();
}
template <>
std::string PrettyPrint(ArtMethod* method) REQUIRES_SHARED(Locks::mutator_lock_) {
return ArtMethod::PrettyMethod(method);
}
template <typename T>
T* ImageWriter::NativeLocationInImage(T* obj) {
if (obj == nullptr || IsInBootImage(obj)) {
return obj;
} else {
NativeObjectRelocation relocation = GetNativeRelocation(obj);
const 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) {
const NativeObjectRelocation relocation = GetNativeRelocation(obj);
const ImageInfo& image_info = GetImageInfo(relocation.oat_index);
return reinterpret_cast<T*>(image_info.image_.Begin() + relocation.offset);
}
class ImageWriter::NativeLocationVisitor {
public:
NativeLocationVisitor(ImageWriter* image_writer, size_t oat_index)
: image_writer_(image_writer),
oat_index_(oat_index) {}
template <typename T>
T* operator()(T* ptr, void** dest_addr) const REQUIRES_SHARED(Locks::mutator_lock_) {
if (ptr != nullptr) {
image_writer_->CopyAndFixupPointer(dest_addr, ptr, oat_index_);
}
// TODO: The caller shall overwrite the value stored by CopyAndFixupPointer()
// with the value we return here. We should try to avoid the duplicate work.
return image_writer_->NativeLocationInImage(ptr);
}
private:
ImageWriter* const image_writer_;
const size_t oat_index_;
};
void ImageWriter::FixupClass(mirror::Class* orig, mirror::Class* copy, size_t oat_index) {
orig->FixupNativePointers(copy, target_ptr_size_, NativeLocationVisitor(this, oat_index));
FixupClassVisitor visitor(this, copy, oat_index);
ObjPtr<mirror::Object>(orig)->VisitReferences(visitor, visitor);
if (kBitstringSubtypeCheckEnabled && compile_app_image_) {
// When we call SubtypeCheck::EnsureInitialize, it Assigns new bitstring
// values to the parent of that class.
//
// Every time this happens, the parent class has to mutate to increment
// the "Next" value.
//
// If any of these parents are in the boot image, the changes [in the parents]
// would be lost when the app image is reloaded.
//
// To prevent newly loaded classes (not in the app image) from being reassigned
// the same bitstring value as an existing app image class, uninitialize
// all the classes in the app image.
//
// On startup, the class linker will then re-initialize all the app
// image bitstrings. See also ClassLinker::AddImageSpace.
MutexLock subtype_check_lock(Thread::Current(), *Locks::subtype_check_lock_);
// Lock every time to prevent a dcheck failure when we suspend with the lock held.
SubtypeCheck<mirror::Class*>::ForceUninitialize(copy);
}
// Remove the clinitThreadId. This is required for image determinism.
copy->SetClinitThreadId(static_cast<pid_t>(0));
}
void ImageWriter::FixupObject(Object* orig, Object* copy, size_t oat_index) {
DCHECK(orig != nullptr);
DCHECK(copy != nullptr);
if (kUseBakerReadBarrier) {
orig->AssertReadBarrierState();
}
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, oat_index);
pointer_arrays_.erase(it);
return;
}
}
if (orig->IsClass()) {
FixupClass(orig->AsClass<kVerifyNone>(), down_cast<mirror::Class*>(copy), oat_index);
} else {
ObjPtr<mirror::ObjectArray<mirror::Class>> class_roots =
Runtime::Current()->GetClassLinker()->GetClassRoots();
if (klass == GetClassRoot<mirror::Method>(class_roots) ||
klass == GetClassRoot<mirror::Constructor>(class_roots)) {
// Need to go update the ArtMethod.
auto* dest = down_cast<mirror::Executable*>(copy);
auto* src = down_cast<mirror::Executable*>(orig);
ArtMethod* src_method = src->GetArtMethod();
CopyAndFixupPointer(dest, mirror::Executable::ArtMethodOffset(), src_method, oat_index);
} else if (klass == GetClassRoot<mirror::DexCache>(class_roots)) {
FixupDexCache(down_cast<mirror::DexCache*>(orig),
down_cast<mirror::DexCache*>(copy),
oat_index);
} 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, oat_index);
orig->VisitReferences(visitor, visitor);
}
}
template <typename T>
void ImageWriter::FixupDexCacheArrayEntry(std::atomic<mirror::DexCachePair<T>>* orig_array,
std::atomic<mirror::DexCachePair<T>>* new_array,
uint32_t array_index,
size_t oat_index) {
static_assert(sizeof(std::atomic<mirror::DexCachePair<T>>) == sizeof(mirror::DexCachePair<T>),
"Size check for removing std::atomic<>.");
mirror::DexCachePair<T>* orig_pair =
reinterpret_cast<mirror::DexCachePair<T>*>(&orig_array[array_index]);
mirror::DexCachePair<T>* new_pair =
reinterpret_cast<mirror::DexCachePair<T>*>(&new_array[array_index]);
CopyAndFixupReference(
new_pair->object.AddressWithoutBarrier(), orig_pair->object.Read(), oat_index);
new_pair->index = orig_pair->index;
}
template <typename T>
void ImageWriter::FixupDexCacheArrayEntry(std::atomic<mirror::NativeDexCachePair<T>>* orig_array,
std::atomic<mirror::NativeDexCachePair<T>>* new_array,
uint32_t array_index,
size_t oat_index) {
static_assert(
sizeof(std::atomic<mirror::NativeDexCachePair<T>>) == sizeof(mirror::NativeDexCachePair<T>),
"Size check for removing std::atomic<>.");
if (target_ptr_size_ == PointerSize::k64) {
DexCache::ConversionPair64* orig_pair =
reinterpret_cast<DexCache::ConversionPair64*>(orig_array) + array_index;
DexCache::ConversionPair64* new_pair =
reinterpret_cast<DexCache::ConversionPair64*>(new_array) + array_index;
*new_pair = *orig_pair; // Copy original value and index.
if (orig_pair->first != 0u) {
CopyAndFixupPointer(reinterpret_cast<void**>(&new_pair->first),
reinterpret_cast64<void*>(orig_pair->first),
oat_index);
}
} else {
DexCache::ConversionPair32* orig_pair =
reinterpret_cast<DexCache::ConversionPair32*>(orig_array) + array_index;
DexCache::ConversionPair32* new_pair =
reinterpret_cast<DexCache::ConversionPair32*>(new_array) + array_index;
*new_pair = *orig_pair; // Copy original value and index.
if (orig_pair->first != 0u) {
CopyAndFixupPointer(reinterpret_cast<void**>(&new_pair->first),
reinterpret_cast32<void*>(orig_pair->first),
oat_index);
}
}
}
void ImageWriter::FixupDexCacheArrayEntry(GcRoot<mirror::CallSite>* orig_array,
GcRoot<mirror::CallSite>* new_array,
uint32_t array_index,
size_t oat_index) {
CopyAndFixupReference(new_array[array_index].AddressWithoutBarrier(),
orig_array[array_index].Read(),
oat_index);
}
template <typename EntryType>
void ImageWriter::FixupDexCacheArray(DexCache* orig_dex_cache,
DexCache* copy_dex_cache,
size_t oat_index,
MemberOffset array_offset,
uint32_t size) {
EntryType* orig_array = orig_dex_cache->GetFieldPtr64<EntryType*>(array_offset);
DCHECK_EQ(orig_array != nullptr, size != 0u);
if (orig_array != nullptr) {
// Though the DexCache array fields are usually treated as native pointers, we clear
// the top 32 bits for 32-bit targets.
CopyAndFixupPointer(copy_dex_cache, array_offset, orig_array, oat_index, PointerSize::k64);
EntryType* new_array = NativeCopyLocation(orig_array);
for (uint32_t i = 0; i != size; ++i) {
FixupDexCacheArrayEntry(orig_array, new_array, i, oat_index);
}
}
}
void ImageWriter::FixupDexCache(DexCache* orig_dex_cache,
DexCache* copy_dex_cache,
size_t oat_index) {
FixupDexCacheArray<mirror::StringDexCacheType>(orig_dex_cache,
copy_dex_cache,
oat_index,
DexCache::StringsOffset(),
orig_dex_cache->NumStrings());
FixupDexCacheArray<mirror::TypeDexCacheType>(orig_dex_cache,
copy_dex_cache,
oat_index,
DexCache::ResolvedTypesOffset(),
orig_dex_cache->NumResolvedTypes());
FixupDexCacheArray<mirror::MethodDexCacheType>(orig_dex_cache,
copy_dex_cache,
oat_index,
DexCache::ResolvedMethodsOffset(),
orig_dex_cache->NumResolvedMethods());
FixupDexCacheArray<mirror::FieldDexCacheType>(orig_dex_cache,
copy_dex_cache,
oat_index,
DexCache::ResolvedFieldsOffset(),
orig_dex_cache->NumResolvedFields());
FixupDexCacheArray<mirror::MethodTypeDexCacheType>(orig_dex_cache,
copy_dex_cache,
oat_index,
DexCache::ResolvedMethodTypesOffset(),
orig_dex_cache->NumResolvedMethodTypes());
FixupDexCacheArray<GcRoot<mirror::CallSite>>(orig_dex_cache,
copy_dex_cache,
oat_index,
DexCache::ResolvedCallSitesOffset(),
orig_dex_cache->NumResolvedCallSites());
// 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(StubType type) const {
DCHECK_LE(type, StubType::kLast);
// 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 StubType::kQuickGenericJNITrampoline:
return static_cast<const uint8_t*>(header.GetQuickGenericJniTrampoline());
case StubType::kInterpreterToInterpreterBridge:
return static_cast<const uint8_t*>(header.GetInterpreterToInterpreterBridge());
case StubType::kInterpreterToCompiledCodeBridge:
return static_cast<const uint8_t*>(header.GetInterpreterToCompiledCodeBridge());
case StubType::kJNIDlsymLookup:
return static_cast<const uint8_t*>(header.GetJniDlsymLookup());
case StubType::kQuickIMTConflictTrampoline:
return static_cast<const uint8_t*>(header.GetQuickImtConflictTrampoline());
case StubType::kQuickResolutionTrampoline:
return static_cast<const uint8_t*>(header.GetQuickResolutionTrampoline());
case StubType::kQuickToInterpreterBridge:
return static_cast<const uint8_t*>(header.GetQuickToInterpreterBridge());
default:
UNREACHABLE();
}
}
const ImageInfo& primary_image_info = GetImageInfo(0);
return GetOatAddressForOffset(primary_image_info.GetStubOffset(type), primary_image_info);
}
const uint8_t* ImageWriter::GetQuickCode(ArtMethod* method,
const ImageInfo& image_info,
bool* quick_is_interpreted) {
DCHECK(!method->IsResolutionMethod()) << method->PrettyMethod();
DCHECK_NE(method, Runtime::Current()->GetImtConflictMethod()) << method->PrettyMethod();
DCHECK(!method->IsImtUnimplementedMethod()) << method->PrettyMethod();
DCHECK(method->IsInvokable()) << method->PrettyMethod();
DCHECK(!IsInBootImage(method)) << method->PrettyMethod();
// 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().Ptr()))) {
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(StubType::kQuickGenericJNITrampoline);
} 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(StubType::kQuickToInterpreterBridge);
*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(StubType::kQuickResolutionTrampoline);
}
if (!IsInBootOatFile(quick_code)) {
// DCHECK_GE(quick_code, oat_data_begin_);
}
return quick_code;
}
void ImageWriter::CopyAndFixupMethod(ArtMethod* orig,
ArtMethod* copy,
size_t oat_index) {
if (orig->IsAbstract()) {
// Ignore the single-implementation info for abstract method.
// Do this on orig instead of copy, otherwise there is a crash due to methods
// are copied before classes.
// TODO: handle fixup of single-implementation method for abstract method.
orig->SetHasSingleImplementation(false);
orig->SetSingleImplementation(
nullptr, Runtime::Current()->GetClassLinker()->GetImagePointerSize());
}
memcpy(copy, orig, ArtMethod::Size(target_ptr_size_));
CopyAndFixupReference(copy->GetDeclaringClassAddressWithoutBarrier(),
orig->GetDeclaringClassUnchecked(),
oat_index);
// 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();
const void* quick_code;
if (orig->IsRuntimeMethod()) {
ImtConflictTable* orig_table = orig->GetImtConflictTable(target_ptr_size_);
if (orig_table != nullptr) {
// Special IMT conflict method, normal IMT conflict method or unimplemented IMT method.
quick_code = GetOatAddress(StubType::kQuickIMTConflictTrampoline);
CopyAndFixupPointer(copy, ArtMethod::DataOffset(target_ptr_size_), orig_table, oat_index);
} else if (UNLIKELY(orig == runtime->GetResolutionMethod())) {
quick_code = GetOatAddress(StubType::kQuickResolutionTrampoline);
} else {
bool found_one = false;
for (size_t i = 0; i < static_cast<size_t>(CalleeSaveType::kLastCalleeSaveType); ++i) {
auto idx = static_cast<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 " << orig->PrettyMethod();
CHECK(copy->IsRuntimeMethod());
CHECK(copy->GetEntryPointFromQuickCompiledCode() == nullptr);
quick_code = nullptr;
}
} 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())) {
quick_code = GetOatAddress(StubType::kQuickToInterpreterBridge);
} else {
bool quick_is_interpreted;
const ImageInfo& image_info = image_infos_[oat_index];
quick_code = GetQuickCode(orig, image_info, &quick_is_interpreted);
// 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(StubType::kJNIDlsymLookup), target_ptr_size_);
MemberOffset offset = ArtMethod::EntryPointFromJniOffset(target_ptr_size_);
const void* dest = reinterpret_cast<const uint8_t*>(copy) + offset.Uint32Value();
RecordImageRelocation(dest, oat_index, /* app_to_boot_image */ compile_app_image_);
} else {
CHECK(copy->GetDataPtrSize(target_ptr_size_) == nullptr);
}
}
}
if (quick_code != nullptr) {
copy->SetEntryPointFromQuickCompiledCodePtrSize(quick_code, target_ptr_size_);
MemberOffset offset = ArtMethod::EntryPointFromQuickCompiledCodeOffset(target_ptr_size_);
const void* dest = reinterpret_cast<const uint8_t*>(copy) + offset.Uint32Value();
RecordImageRelocation(dest, oat_index, /* app_to_boot_image */ IsInBootOatFile(quick_code));
}
}
size_t ImageWriter::ImageInfo::GetBinSizeSum(Bin up_to) const {
DCHECK_LE(static_cast<size_t>(up_to), kNumberOfBins);
return std::accumulate(&bin_slot_sizes_[0],
&bin_slot_sizes_[0] + static_cast<size_t>(up_to),
/*init*/ static_cast<size_t>(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(), Bin::kMirrorCount);
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 NativeObjectRelocationType::kArtField:
case NativeObjectRelocationType::kArtFieldArray:
return Bin::kArtField;
case NativeObjectRelocationType::kArtMethodClean:
case NativeObjectRelocationType::kArtMethodArrayClean:
return Bin::kArtMethodClean;
case NativeObjectRelocationType::kArtMethodDirty:
case NativeObjectRelocationType::kArtMethodArrayDirty:
return Bin::kArtMethodDirty;
case NativeObjectRelocationType::kDexCacheArray:
return Bin::kDexCacheArray;
case NativeObjectRelocationType::kRuntimeMethod:
return Bin::kRuntimeMethod;
case NativeObjectRelocationType::kIMTable:
return Bin::kImTable;
case NativeObjectRelocationType::kIMTConflictTable:
return Bin::kIMTConflictTable;
}
UNREACHABLE();
}
size_t ImageWriter::GetOatIndex(mirror::Object* obj) const {
if (!IsMultiImage()) {
return GetDefaultOatIndex();
}
auto it = oat_index_map_.find(obj);
DCHECK(it != oat_index_map_.end()) << obj;
return it->second;
}
size_t ImageWriter::GetOatIndexForDexFile(const DexFile* dex_file) const {
if (!IsMultiImage()) {
return GetDefaultOatIndex();
}
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(ObjPtr<mirror::DexCache> dex_cache) const {
return (dex_cache == nullptr)
? GetDefaultOatIndex()
: 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.SetStubOffset(StubType::kInterpreterToInterpreterBridge,
oat_header.GetInterpreterToInterpreterBridgeOffset());
cur_image_info.SetStubOffset(StubType::kInterpreterToCompiledCodeBridge,
oat_header.GetInterpreterToCompiledCodeBridgeOffset());
cur_image_info.SetStubOffset(StubType::kJNIDlsymLookup,
oat_header.GetJniDlsymLookupOffset());
cur_image_info.SetStubOffset(StubType::kQuickGenericJNITrampoline,
oat_header.GetQuickGenericJniTrampolineOffset());
cur_image_info.SetStubOffset(StubType::kQuickIMTConflictTrampoline,
oat_header.GetQuickImtConflictTrampolineOffset());
cur_image_info.SetStubOffset(StubType::kQuickResolutionTrampoline,
oat_header.GetQuickResolutionTrampolineOffset());
cur_image_info.SetStubOffset(StubType::kQuickToInterpreterBridge,
oat_header.GetQuickToInterpreterBridgeOffset());
}
}
ImageWriter::ImageWriter(
const CompilerOptions& compiler_options,
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,
const HashSet<std::string>* dirty_image_objects)
: compiler_options_(compiler_options),
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_options.GetInstructionSet())),
image_infos_(oat_filenames.size()),
dirty_methods_(0u),
clean_methods_(0u),
boot_image_live_objects_(nullptr),
image_storage_mode_(image_storage_mode),
oat_filenames_(oat_filenames),
dex_file_oat_index_map_(dex_file_oat_index_map),
dirty_image_objects_(dirty_image_objects) {
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) {}
template <bool kCheckNotNull /* = true */>
void ImageWriter::RecordImageRelocation(const void* dest,
size_t oat_index,
bool app_to_boot_image /* = false */) {
// Check that we're not recording a relocation for null.
if (kCheckNotNull) {
DCHECK(reinterpret_cast<const uint32_t*>(dest)[0] != 0u);
}
// Calculate the offset within the image.
ImageInfo* image_info = &image_infos_[oat_index];
DCHECK(image_info->image_.HasAddress(dest))
<< "MemMap range " << static_cast<const void*>(image_info->image_.Begin())
<< "-" << static_cast<const void*>(image_info->image_.End())
<< " does not contain " << dest;
size_t offset = reinterpret_cast<const uint8_t*>(dest) - image_info->image_.Begin();
ImageHeader* const image_header = reinterpret_cast<ImageHeader*>(image_info->image_.Begin());
size_t image_end = image_header->GetClassTableSection().End();
DCHECK_LT(offset, image_end);
// Calculate the location index.
size_t size = RelocationIndex(image_end, target_ptr_size_);
size_t index = RelocationIndex(offset, target_ptr_size_);
if (app_to_boot_image) {
index += size;
}
// Mark the location in the bitmap.
DCHECK(compile_app_image_ || !app_to_boot_image);
MemoryRegion region(image_info->relocation_bitmap_.data(), image_info->relocation_bitmap_.size());
BitMemoryRegion bit_region(region, /* bit_offset */ 0u, compile_app_image_ ? 2u * size : size);
DCHECK(!bit_region.LoadBit(index));
bit_region.StoreBit(index, /* value*/ true);
}
template <typename DestType>
void ImageWriter::CopyAndFixupReference(DestType* dest,
ObjPtr<mirror::Object> src,
size_t oat_index) {
static_assert(std::is_same<DestType, mirror::CompressedReference<mirror::Object>>::value ||
std::is_same<DestType, mirror::HeapReference<mirror::Object>>::value,
"DestType must be a Compressed-/HeapReference<Object>.");
dest->Assign(GetImageAddress(src.Ptr()));
if (src != nullptr) {
RecordImageRelocation(dest, oat_index, /* app_to_boot_image */ IsInBootImage(src.Ptr()));
}
}
void ImageWriter::CopyAndFixupPointer(void** target,
void* value,
size_t oat_index,
PointerSize pointer_size) {
void* new_value = NativeLocationInImage(value);
if (pointer_size == PointerSize::k32) {
*reinterpret_cast<uint32_t*>(target) = reinterpret_cast32<uint32_t>(new_value);
} else {
*reinterpret_cast<uint64_t*>(target) = reinterpret_cast64<uint64_t>(new_value);
}
DCHECK(value != nullptr);
RecordImageRelocation(target, oat_index, /* app_to_boot_image */ IsInBootImage(value));
}
void ImageWriter::CopyAndFixupPointer(void** target, void* value, size_t oat_index)
REQUIRES_SHARED(Locks::mutator_lock_) {
CopyAndFixupPointer(target, value, oat_index, target_ptr_size_);
}
void ImageWriter::CopyAndFixupPointer(
void* object, MemberOffset offset, void* value, size_t oat_index, PointerSize pointer_size) {
void** target =
reinterpret_cast<void**>(reinterpret_cast<uint8_t*>(object) + offset.Uint32Value());
return CopyAndFixupPointer(target, value, oat_index, pointer_size);
}
void ImageWriter::CopyAndFixupPointer(
void* object, MemberOffset offset, void* value, size_t oat_index) {
return CopyAndFixupPointer(object, offset, value, oat_index, target_ptr_size_);
}
} // namespace linker
} // namespace art