image_writer.cc revision 90ca5c0301651101de0e363842e5d08ae65233f7
1/* 2 * Copyright (C) 2011 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#include "image_writer.h" 18 19#include <sys/stat.h> 20 21#include <memory> 22#include <vector> 23 24#include "base/logging.h" 25#include "base/unix_file/fd_file.h" 26#include "class_linker.h" 27#include "compiled_method.h" 28#include "dex_file-inl.h" 29#include "driver/compiler_driver.h" 30#include "elf_file.h" 31#include "elf_utils.h" 32#include "elf_patcher.h" 33#include "elf_writer.h" 34#include "gc/accounting/card_table-inl.h" 35#include "gc/accounting/heap_bitmap.h" 36#include "gc/accounting/space_bitmap-inl.h" 37#include "gc/heap.h" 38#include "gc/space/large_object_space.h" 39#include "gc/space/space-inl.h" 40#include "globals.h" 41#include "image.h" 42#include "intern_table.h" 43#include "lock_word.h" 44#include "mirror/art_field-inl.h" 45#include "mirror/art_method-inl.h" 46#include "mirror/array-inl.h" 47#include "mirror/class-inl.h" 48#include "mirror/class_loader.h" 49#include "mirror/dex_cache-inl.h" 50#include "mirror/object-inl.h" 51#include "mirror/object_array-inl.h" 52#include "mirror/string-inl.h" 53#include "oat.h" 54#include "oat_file.h" 55#include "runtime.h" 56#include "scoped_thread_state_change.h" 57#include "handle_scope-inl.h" 58#include "utils.h" 59 60using ::art::mirror::ArtField; 61using ::art::mirror::ArtMethod; 62using ::art::mirror::Class; 63using ::art::mirror::DexCache; 64using ::art::mirror::EntryPointFromInterpreter; 65using ::art::mirror::Object; 66using ::art::mirror::ObjectArray; 67using ::art::mirror::String; 68 69namespace art { 70 71bool ImageWriter::Write(const std::string& image_filename, 72 uintptr_t image_begin, 73 const std::string& oat_filename, 74 const std::string& oat_location, 75 bool compile_pic) { 76 CHECK(!image_filename.empty()); 77 78 CHECK_NE(image_begin, 0U); 79 image_begin_ = reinterpret_cast<byte*>(image_begin); 80 compile_pic_ = compile_pic; 81 82 ClassLinker* class_linker = Runtime::Current()->GetClassLinker(); 83 84 std::unique_ptr<File> oat_file(OS::OpenFileReadWrite(oat_filename.c_str())); 85 if (oat_file.get() == NULL) { 86 LOG(ERROR) << "Failed to open oat file " << oat_filename << " for " << oat_location; 87 return false; 88 } 89 std::string error_msg; 90 oat_file_ = OatFile::OpenReadable(oat_file.get(), oat_location, &error_msg); 91 if (oat_file_ == nullptr) { 92 LOG(ERROR) << "Failed to open writable oat file " << oat_filename << " for " << oat_location 93 << ": " << error_msg; 94 return false; 95 } 96 CHECK_EQ(class_linker->RegisterOatFile(oat_file_), oat_file_); 97 98 interpreter_to_interpreter_bridge_offset_ = 99 oat_file_->GetOatHeader().GetInterpreterToInterpreterBridgeOffset(); 100 interpreter_to_compiled_code_bridge_offset_ = 101 oat_file_->GetOatHeader().GetInterpreterToCompiledCodeBridgeOffset(); 102 103 jni_dlsym_lookup_offset_ = oat_file_->GetOatHeader().GetJniDlsymLookupOffset(); 104 105 portable_imt_conflict_trampoline_offset_ = 106 oat_file_->GetOatHeader().GetPortableImtConflictTrampolineOffset(); 107 portable_resolution_trampoline_offset_ = 108 oat_file_->GetOatHeader().GetPortableResolutionTrampolineOffset(); 109 portable_to_interpreter_bridge_offset_ = 110 oat_file_->GetOatHeader().GetPortableToInterpreterBridgeOffset(); 111 112 quick_generic_jni_trampoline_offset_ = 113 oat_file_->GetOatHeader().GetQuickGenericJniTrampolineOffset(); 114 quick_imt_conflict_trampoline_offset_ = 115 oat_file_->GetOatHeader().GetQuickImtConflictTrampolineOffset(); 116 quick_resolution_trampoline_offset_ = 117 oat_file_->GetOatHeader().GetQuickResolutionTrampolineOffset(); 118 quick_to_interpreter_bridge_offset_ = 119 oat_file_->GetOatHeader().GetQuickToInterpreterBridgeOffset(); 120 { 121 Thread::Current()->TransitionFromSuspendedToRunnable(); 122 PruneNonImageClasses(); // Remove junk 123 ComputeLazyFieldsForImageClasses(); // Add useful information 124 ComputeEagerResolvedStrings(); 125 Thread::Current()->TransitionFromRunnableToSuspended(kNative); 126 } 127 gc::Heap* heap = Runtime::Current()->GetHeap(); 128 heap->CollectGarbage(false); // Remove garbage. 129 130 if (!AllocMemory()) { 131 return false; 132 } 133 134 if (kIsDebugBuild) { 135 ScopedObjectAccess soa(Thread::Current()); 136 CheckNonImageClassesRemoved(); 137 } 138 139 Thread::Current()->TransitionFromSuspendedToRunnable(); 140 size_t oat_loaded_size = 0; 141 size_t oat_data_offset = 0; 142 ElfWriter::GetOatElfInformation(oat_file.get(), oat_loaded_size, oat_data_offset); 143 CalculateNewObjectOffsets(oat_loaded_size, oat_data_offset); 144 CopyAndFixupObjects(); 145 146 PatchOatCodeAndMethods(oat_file.get()); 147 Thread::Current()->TransitionFromRunnableToSuspended(kNative); 148 149 std::unique_ptr<File> image_file(OS::CreateEmptyFile(image_filename.c_str())); 150 ImageHeader* image_header = reinterpret_cast<ImageHeader*>(image_->Begin()); 151 if (image_file.get() == NULL) { 152 LOG(ERROR) << "Failed to open image file " << image_filename; 153 return false; 154 } 155 if (fchmod(image_file->Fd(), 0644) != 0) { 156 PLOG(ERROR) << "Failed to make image file world readable: " << image_filename; 157 return EXIT_FAILURE; 158 } 159 160 // Write out the image. 161 CHECK_EQ(image_end_, image_header->GetImageSize()); 162 if (!image_file->WriteFully(image_->Begin(), image_end_)) { 163 PLOG(ERROR) << "Failed to write image file " << image_filename; 164 return false; 165 } 166 167 // Write out the image bitmap at the page aligned start of the image end. 168 CHECK_ALIGNED(image_header->GetImageBitmapOffset(), kPageSize); 169 if (!image_file->Write(reinterpret_cast<char*>(image_bitmap_->Begin()), 170 image_header->GetImageBitmapSize(), 171 image_header->GetImageBitmapOffset())) { 172 PLOG(ERROR) << "Failed to write image file " << image_filename; 173 return false; 174 } 175 176 return true; 177} 178 179void ImageWriter::SetImageOffset(mirror::Object* object, size_t offset) { 180 DCHECK(object != nullptr); 181 DCHECK_NE(offset, 0U); 182 DCHECK(!IsImageOffsetAssigned(object)); 183 mirror::Object* obj = reinterpret_cast<mirror::Object*>(image_->Begin() + offset); 184 DCHECK_ALIGNED(obj, kObjectAlignment); 185 image_bitmap_->Set(obj); 186 // Before we stomp over the lock word, save the hash code for later. 187 Monitor::Deflate(Thread::Current(), object);; 188 LockWord lw(object->GetLockWord(false)); 189 switch (lw.GetState()) { 190 case LockWord::kFatLocked: { 191 LOG(FATAL) << "Fat locked object " << obj << " found during object copy"; 192 break; 193 } 194 case LockWord::kThinLocked: { 195 LOG(FATAL) << "Thin locked object " << obj << " found during object copy"; 196 break; 197 } 198 case LockWord::kUnlocked: 199 // No hash, don't need to save it. 200 break; 201 case LockWord::kHashCode: 202 saved_hashes_.push_back(std::make_pair(obj, lw.GetHashCode())); 203 break; 204 default: 205 LOG(FATAL) << "Unreachable."; 206 break; 207 } 208 object->SetLockWord(LockWord::FromForwardingAddress(offset), false); 209 DCHECK(IsImageOffsetAssigned(object)); 210} 211 212void ImageWriter::AssignImageOffset(mirror::Object* object) { 213 DCHECK(object != nullptr); 214 SetImageOffset(object, image_end_); 215 image_end_ += RoundUp(object->SizeOf(), 8); // 64-bit alignment 216 DCHECK_LT(image_end_, image_->Size()); 217} 218 219bool ImageWriter::IsImageOffsetAssigned(mirror::Object* object) const { 220 DCHECK(object != nullptr); 221 return object->GetLockWord(false).GetState() == LockWord::kForwardingAddress; 222} 223 224size_t ImageWriter::GetImageOffset(mirror::Object* object) const { 225 DCHECK(object != nullptr); 226 DCHECK(IsImageOffsetAssigned(object)); 227 LockWord lock_word = object->GetLockWord(false); 228 size_t offset = lock_word.ForwardingAddress(); 229 DCHECK_LT(offset, image_end_); 230 return offset; 231} 232 233bool ImageWriter::AllocMemory() { 234 size_t length = RoundUp(Runtime::Current()->GetHeap()->GetTotalMemory(), kPageSize); 235 std::string error_msg; 236 image_.reset(MemMap::MapAnonymous("image writer image", NULL, length, PROT_READ | PROT_WRITE, 237 true, &error_msg)); 238 if (UNLIKELY(image_.get() == nullptr)) { 239 LOG(ERROR) << "Failed to allocate memory for image file generation: " << error_msg; 240 return false; 241 } 242 243 // Create the image bitmap. 244 image_bitmap_.reset(gc::accounting::ContinuousSpaceBitmap::Create("image bitmap", image_->Begin(), 245 length)); 246 if (image_bitmap_.get() == nullptr) { 247 LOG(ERROR) << "Failed to allocate memory for image bitmap"; 248 return false; 249 } 250 return true; 251} 252 253void ImageWriter::ComputeLazyFieldsForImageClasses() { 254 ClassLinker* class_linker = Runtime::Current()->GetClassLinker(); 255 class_linker->VisitClassesWithoutClassesLock(ComputeLazyFieldsForClassesVisitor, NULL); 256} 257 258bool ImageWriter::ComputeLazyFieldsForClassesVisitor(Class* c, void* /*arg*/) { 259 Thread* self = Thread::Current(); 260 StackHandleScope<1> hs(self); 261 mirror::Class::ComputeName(hs.NewHandle(c)); 262 return true; 263} 264 265void ImageWriter::ComputeEagerResolvedStringsCallback(Object* obj, void* arg) { 266 if (!obj->GetClass()->IsStringClass()) { 267 return; 268 } 269 mirror::String* string = obj->AsString(); 270 const uint16_t* utf16_string = string->GetCharArray()->GetData() + string->GetOffset(); 271 ClassLinker* class_linker = Runtime::Current()->GetClassLinker(); 272 ReaderMutexLock mu(Thread::Current(), *class_linker->DexLock()); 273 size_t dex_cache_count = class_linker->GetDexCacheCount(); 274 for (size_t i = 0; i < dex_cache_count; ++i) { 275 DexCache* dex_cache = class_linker->GetDexCache(i); 276 const DexFile& dex_file = *dex_cache->GetDexFile(); 277 const DexFile::StringId* string_id; 278 if (UNLIKELY(string->GetLength() == 0)) { 279 string_id = dex_file.FindStringId(""); 280 } else { 281 string_id = dex_file.FindStringId(utf16_string); 282 } 283 if (string_id != nullptr) { 284 // This string occurs in this dex file, assign the dex cache entry. 285 uint32_t string_idx = dex_file.GetIndexForStringId(*string_id); 286 if (dex_cache->GetResolvedString(string_idx) == NULL) { 287 dex_cache->SetResolvedString(string_idx, string); 288 } 289 } 290 } 291} 292 293void ImageWriter::ComputeEagerResolvedStrings() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 294 ReaderMutexLock mu(Thread::Current(), *Locks::heap_bitmap_lock_); 295 Runtime::Current()->GetHeap()->VisitObjects(ComputeEagerResolvedStringsCallback, this); 296} 297 298bool ImageWriter::IsImageClass(Class* klass) { 299 std::string temp; 300 return compiler_driver_.IsImageClass(klass->GetDescriptor(&temp)); 301} 302 303struct NonImageClasses { 304 ImageWriter* image_writer; 305 std::set<std::string>* non_image_classes; 306}; 307 308void ImageWriter::PruneNonImageClasses() { 309 if (compiler_driver_.GetImageClasses() == NULL) { 310 return; 311 } 312 Runtime* runtime = Runtime::Current(); 313 ClassLinker* class_linker = runtime->GetClassLinker(); 314 315 // Make a list of classes we would like to prune. 316 std::set<std::string> non_image_classes; 317 NonImageClasses context; 318 context.image_writer = this; 319 context.non_image_classes = &non_image_classes; 320 class_linker->VisitClasses(NonImageClassesVisitor, &context); 321 322 // Remove the undesired classes from the class roots. 323 for (const std::string& it : non_image_classes) { 324 class_linker->RemoveClass(it.c_str(), NULL); 325 } 326 327 // Clear references to removed classes from the DexCaches. 328 ArtMethod* resolution_method = runtime->GetResolutionMethod(); 329 ReaderMutexLock mu(Thread::Current(), *class_linker->DexLock()); 330 size_t dex_cache_count = class_linker->GetDexCacheCount(); 331 for (size_t idx = 0; idx < dex_cache_count; ++idx) { 332 DexCache* dex_cache = class_linker->GetDexCache(idx); 333 for (size_t i = 0; i < dex_cache->NumResolvedTypes(); i++) { 334 Class* klass = dex_cache->GetResolvedType(i); 335 if (klass != NULL && !IsImageClass(klass)) { 336 dex_cache->SetResolvedType(i, NULL); 337 } 338 } 339 for (size_t i = 0; i < dex_cache->NumResolvedMethods(); i++) { 340 ArtMethod* method = dex_cache->GetResolvedMethod(i); 341 if (method != NULL && !IsImageClass(method->GetDeclaringClass())) { 342 dex_cache->SetResolvedMethod(i, resolution_method); 343 } 344 } 345 for (size_t i = 0; i < dex_cache->NumResolvedFields(); i++) { 346 ArtField* field = dex_cache->GetResolvedField(i); 347 if (field != NULL && !IsImageClass(field->GetDeclaringClass())) { 348 dex_cache->SetResolvedField(i, NULL); 349 } 350 } 351 } 352} 353 354bool ImageWriter::NonImageClassesVisitor(Class* klass, void* arg) { 355 NonImageClasses* context = reinterpret_cast<NonImageClasses*>(arg); 356 if (!context->image_writer->IsImageClass(klass)) { 357 std::string temp; 358 context->non_image_classes->insert(klass->GetDescriptor(&temp)); 359 } 360 return true; 361} 362 363void ImageWriter::CheckNonImageClassesRemoved() 364 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 365 if (compiler_driver_.GetImageClasses() != nullptr) { 366 gc::Heap* heap = Runtime::Current()->GetHeap(); 367 ReaderMutexLock mu(Thread::Current(), *Locks::heap_bitmap_lock_); 368 heap->VisitObjects(CheckNonImageClassesRemovedCallback, this); 369 } 370} 371 372void ImageWriter::CheckNonImageClassesRemovedCallback(Object* obj, void* arg) { 373 ImageWriter* image_writer = reinterpret_cast<ImageWriter*>(arg); 374 if (obj->IsClass()) { 375 Class* klass = obj->AsClass(); 376 if (!image_writer->IsImageClass(klass)) { 377 image_writer->DumpImageClasses(); 378 std::string temp; 379 CHECK(image_writer->IsImageClass(klass)) << klass->GetDescriptor(&temp) 380 << " " << PrettyDescriptor(klass); 381 } 382 } 383} 384 385void ImageWriter::DumpImageClasses() { 386 const std::set<std::string>* image_classes = compiler_driver_.GetImageClasses(); 387 CHECK(image_classes != NULL); 388 for (const std::string& image_class : *image_classes) { 389 LOG(INFO) << " " << image_class; 390 } 391} 392 393void ImageWriter::CalculateObjectOffsets(Object* obj) { 394 DCHECK(obj != NULL); 395 // if it is a string, we want to intern it if its not interned. 396 if (obj->GetClass()->IsStringClass()) { 397 // we must be an interned string that was forward referenced and already assigned 398 if (IsImageOffsetAssigned(obj)) { 399 DCHECK_EQ(obj, obj->AsString()->Intern()); 400 return; 401 } 402 mirror::String* const interned = obj->AsString()->Intern(); 403 if (obj != interned) { 404 if (!IsImageOffsetAssigned(interned)) { 405 // interned obj is after us, allocate its location early 406 AssignImageOffset(interned); 407 } 408 // point those looking for this object to the interned version. 409 SetImageOffset(obj, GetImageOffset(interned)); 410 return; 411 } 412 // else (obj == interned), nothing to do but fall through to the normal case 413 } 414 415 AssignImageOffset(obj); 416} 417 418ObjectArray<Object>* ImageWriter::CreateImageRoots() const { 419 Runtime* runtime = Runtime::Current(); 420 ClassLinker* class_linker = runtime->GetClassLinker(); 421 Thread* self = Thread::Current(); 422 StackHandleScope<3> hs(self); 423 Handle<Class> object_array_class(hs.NewHandle( 424 class_linker->FindSystemClass(self, "[Ljava/lang/Object;"))); 425 426 // build an Object[] of all the DexCaches used in the source_space_. 427 // Since we can't hold the dex lock when allocating the dex_caches 428 // ObjectArray, we lock the dex lock twice, first to get the number 429 // of dex caches first and then lock it again to copy the dex 430 // caches. We check that the number of dex caches does not change. 431 size_t dex_cache_count; 432 { 433 ReaderMutexLock mu(Thread::Current(), *class_linker->DexLock()); 434 dex_cache_count = class_linker->GetDexCacheCount(); 435 } 436 Handle<ObjectArray<Object>> dex_caches( 437 hs.NewHandle(ObjectArray<Object>::Alloc(self, object_array_class.Get(), 438 dex_cache_count))); 439 CHECK(dex_caches.Get() != nullptr) << "Failed to allocate a dex cache array."; 440 { 441 ReaderMutexLock mu(Thread::Current(), *class_linker->DexLock()); 442 CHECK_EQ(dex_cache_count, class_linker->GetDexCacheCount()) 443 << "The number of dex caches changed."; 444 for (size_t i = 0; i < dex_cache_count; ++i) { 445 dex_caches->Set<false>(i, class_linker->GetDexCache(i)); 446 } 447 } 448 449 // build an Object[] of the roots needed to restore the runtime 450 Handle<ObjectArray<Object>> image_roots(hs.NewHandle( 451 ObjectArray<Object>::Alloc(self, object_array_class.Get(), ImageHeader::kImageRootsMax))); 452 image_roots->Set<false>(ImageHeader::kResolutionMethod, runtime->GetResolutionMethod()); 453 image_roots->Set<false>(ImageHeader::kImtConflictMethod, runtime->GetImtConflictMethod()); 454 image_roots->Set<false>(ImageHeader::kImtUnimplementedMethod, 455 runtime->GetImtUnimplementedMethod()); 456 image_roots->Set<false>(ImageHeader::kDefaultImt, runtime->GetDefaultImt()); 457 image_roots->Set<false>(ImageHeader::kCalleeSaveMethod, 458 runtime->GetCalleeSaveMethod(Runtime::kSaveAll)); 459 image_roots->Set<false>(ImageHeader::kRefsOnlySaveMethod, 460 runtime->GetCalleeSaveMethod(Runtime::kRefsOnly)); 461 image_roots->Set<false>(ImageHeader::kRefsAndArgsSaveMethod, 462 runtime->GetCalleeSaveMethod(Runtime::kRefsAndArgs)); 463 image_roots->Set<false>(ImageHeader::kDexCaches, dex_caches.Get()); 464 image_roots->Set<false>(ImageHeader::kClassRoots, class_linker->GetClassRoots()); 465 for (int i = 0; i < ImageHeader::kImageRootsMax; i++) { 466 CHECK(image_roots->Get(i) != NULL); 467 } 468 return image_roots.Get(); 469} 470 471// Walk instance fields of the given Class. Separate function to allow recursion on the super 472// class. 473void ImageWriter::WalkInstanceFields(mirror::Object* obj, mirror::Class* klass) { 474 // Visit fields of parent classes first. 475 StackHandleScope<1> hs(Thread::Current()); 476 Handle<mirror::Class> h_class(hs.NewHandle(klass)); 477 mirror::Class* super = h_class->GetSuperClass(); 478 if (super != nullptr) { 479 WalkInstanceFields(obj, super); 480 } 481 // 482 size_t num_reference_fields = h_class->NumReferenceInstanceFields(); 483 for (size_t i = 0; i < num_reference_fields; ++i) { 484 mirror::ArtField* field = h_class->GetInstanceField(i); 485 MemberOffset field_offset = field->GetOffset(); 486 mirror::Object* value = obj->GetFieldObject<mirror::Object>(field_offset); 487 if (value != nullptr) { 488 WalkFieldsInOrder(value); 489 } 490 } 491} 492 493// For an unvisited object, visit it then all its children found via fields. 494void ImageWriter::WalkFieldsInOrder(mirror::Object* obj) { 495 if (!IsImageOffsetAssigned(obj)) { 496 // Walk instance fields of all objects 497 StackHandleScope<2> hs(Thread::Current()); 498 Handle<mirror::Object> h_obj(hs.NewHandle(obj)); 499 Handle<mirror::Class> klass(hs.NewHandle(obj->GetClass())); 500 // visit the object itself. 501 CalculateObjectOffsets(h_obj.Get()); 502 WalkInstanceFields(h_obj.Get(), klass.Get()); 503 // Walk static fields of a Class. 504 if (h_obj->IsClass()) { 505 size_t num_static_fields = klass->NumReferenceStaticFields(); 506 for (size_t i = 0; i < num_static_fields; ++i) { 507 mirror::ArtField* field = klass->GetStaticField(i); 508 MemberOffset field_offset = field->GetOffset(); 509 mirror::Object* value = h_obj->GetFieldObject<mirror::Object>(field_offset); 510 if (value != nullptr) { 511 WalkFieldsInOrder(value); 512 } 513 } 514 } else if (h_obj->IsObjectArray()) { 515 // Walk elements of an object array. 516 int32_t length = h_obj->AsObjectArray<mirror::Object>()->GetLength(); 517 for (int32_t i = 0; i < length; i++) { 518 mirror::ObjectArray<mirror::Object>* obj_array = h_obj->AsObjectArray<mirror::Object>(); 519 mirror::Object* value = obj_array->Get(i); 520 if (value != nullptr) { 521 WalkFieldsInOrder(value); 522 } 523 } 524 } 525 } 526} 527 528void ImageWriter::WalkFieldsCallback(mirror::Object* obj, void* arg) { 529 ImageWriter* writer = reinterpret_cast<ImageWriter*>(arg); 530 DCHECK(writer != nullptr); 531 writer->WalkFieldsInOrder(obj); 532} 533 534void ImageWriter::CalculateNewObjectOffsets(size_t oat_loaded_size, size_t oat_data_offset) { 535 CHECK_NE(0U, oat_loaded_size); 536 Thread* self = Thread::Current(); 537 StackHandleScope<1> hs(self); 538 Handle<ObjectArray<Object>> image_roots(hs.NewHandle(CreateImageRoots())); 539 540 gc::Heap* heap = Runtime::Current()->GetHeap(); 541 DCHECK_EQ(0U, image_end_); 542 543 // Leave space for the header, but do not write it yet, we need to 544 // know where image_roots is going to end up 545 image_end_ += RoundUp(sizeof(ImageHeader), 8); // 64-bit-alignment 546 547 { 548 WriterMutexLock mu(self, *Locks::heap_bitmap_lock_); 549 // TODO: Image spaces only? 550 const char* old = self->StartAssertNoThreadSuspension("ImageWriter"); 551 DCHECK_LT(image_end_, image_->Size()); 552 // Clear any pre-existing monitors which may have been in the monitor words. 553 heap->VisitObjects(WalkFieldsCallback, this); 554 self->EndAssertNoThreadSuspension(old); 555 } 556 557 const byte* oat_file_begin = image_begin_ + RoundUp(image_end_, kPageSize); 558 const byte* oat_file_end = oat_file_begin + oat_loaded_size; 559 oat_data_begin_ = oat_file_begin + oat_data_offset; 560 const byte* oat_data_end = oat_data_begin_ + oat_file_->Size(); 561 562 // Return to write header at start of image with future location of image_roots. At this point, 563 // image_end_ is the size of the image (excluding bitmaps). 564 const size_t heap_bytes_per_bitmap_byte = kBitsPerByte * kObjectAlignment; 565 const size_t bitmap_bytes = RoundUp(image_end_, heap_bytes_per_bitmap_byte) / 566 heap_bytes_per_bitmap_byte; 567 ImageHeader image_header(PointerToLowMemUInt32(image_begin_), 568 static_cast<uint32_t>(image_end_), 569 RoundUp(image_end_, kPageSize), 570 RoundUp(bitmap_bytes, kPageSize), 571 PointerToLowMemUInt32(GetImageAddress(image_roots.Get())), 572 oat_file_->GetOatHeader().GetChecksum(), 573 PointerToLowMemUInt32(oat_file_begin), 574 PointerToLowMemUInt32(oat_data_begin_), 575 PointerToLowMemUInt32(oat_data_end), 576 PointerToLowMemUInt32(oat_file_end), 577 compile_pic_); 578 memcpy(image_->Begin(), &image_header, sizeof(image_header)); 579 580 // Note that image_end_ is left at end of used space 581} 582 583void ImageWriter::CopyAndFixupObjects() 584 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 585 Thread* self = Thread::Current(); 586 const char* old_cause = self->StartAssertNoThreadSuspension("ImageWriter"); 587 gc::Heap* heap = Runtime::Current()->GetHeap(); 588 // TODO: heap validation can't handle this fix up pass 589 heap->DisableObjectValidation(); 590 // TODO: Image spaces only? 591 WriterMutexLock mu(self, *Locks::heap_bitmap_lock_); 592 heap->VisitObjects(CopyAndFixupObjectsCallback, this); 593 // Fix up the object previously had hash codes. 594 for (const std::pair<mirror::Object*, uint32_t>& hash_pair : saved_hashes_) { 595 hash_pair.first->SetLockWord(LockWord::FromHashCode(hash_pair.second), false); 596 } 597 saved_hashes_.clear(); 598 self->EndAssertNoThreadSuspension(old_cause); 599} 600 601void ImageWriter::CopyAndFixupObjectsCallback(Object* obj, void* arg) { 602 DCHECK(obj != nullptr); 603 DCHECK(arg != nullptr); 604 ImageWriter* image_writer = reinterpret_cast<ImageWriter*>(arg); 605 // see GetLocalAddress for similar computation 606 size_t offset = image_writer->GetImageOffset(obj); 607 byte* dst = image_writer->image_->Begin() + offset; 608 const byte* src = reinterpret_cast<const byte*>(obj); 609 size_t n = obj->SizeOf(); 610 DCHECK_LT(offset + n, image_writer->image_->Size()); 611 memcpy(dst, src, n); 612 Object* copy = reinterpret_cast<Object*>(dst); 613 // Write in a hash code of objects which have inflated monitors or a hash code in their monitor 614 // word. 615 copy->SetLockWord(LockWord(), false); 616 image_writer->FixupObject(obj, copy); 617} 618 619class FixupVisitor { 620 public: 621 FixupVisitor(ImageWriter* image_writer, Object* copy) : image_writer_(image_writer), copy_(copy) { 622 } 623 624 void operator()(Object* obj, MemberOffset offset, bool /*is_static*/) const 625 EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_, Locks::heap_bitmap_lock_) { 626 Object* ref = obj->GetFieldObject<Object, kVerifyNone>(offset); 627 // Use SetFieldObjectWithoutWriteBarrier to avoid card marking since we are writing to the 628 // image. 629 copy_->SetFieldObjectWithoutWriteBarrier<false, true, kVerifyNone>( 630 offset, image_writer_->GetImageAddress(ref)); 631 } 632 633 // java.lang.ref.Reference visitor. 634 void operator()(mirror::Class* /*klass*/, mirror::Reference* ref) const 635 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) 636 EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) { 637 copy_->SetFieldObjectWithoutWriteBarrier<false, true, kVerifyNone>( 638 mirror::Reference::ReferentOffset(), image_writer_->GetImageAddress(ref->GetReferent())); 639 } 640 641 protected: 642 ImageWriter* const image_writer_; 643 mirror::Object* const copy_; 644}; 645 646class FixupClassVisitor FINAL : public FixupVisitor { 647 public: 648 FixupClassVisitor(ImageWriter* image_writer, Object* copy) : FixupVisitor(image_writer, copy) { 649 } 650 651 void operator()(Object* obj, MemberOffset offset, bool /*is_static*/) const 652 EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_, Locks::heap_bitmap_lock_) { 653 DCHECK(obj->IsClass()); 654 FixupVisitor::operator()(obj, offset, false); 655 656 if (offset.Uint32Value() < mirror::Class::EmbeddedVTableOffset().Uint32Value()) { 657 return; 658 } 659 } 660 661 void operator()(mirror::Class* /*klass*/, mirror::Reference* ref) const 662 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) 663 EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) { 664 LOG(FATAL) << "Reference not expected here."; 665 } 666}; 667 668void ImageWriter::FixupObject(Object* orig, Object* copy) { 669 DCHECK(orig != nullptr); 670 DCHECK(copy != nullptr); 671 if (kUseBakerOrBrooksReadBarrier) { 672 orig->AssertReadBarrierPointer(); 673 if (kUseBrooksReadBarrier) { 674 // Note the address 'copy' isn't the same as the image address of 'orig'. 675 copy->SetReadBarrierPointer(GetImageAddress(orig)); 676 DCHECK_EQ(copy->GetReadBarrierPointer(), GetImageAddress(orig)); 677 } 678 } 679 if (orig->IsClass() && orig->AsClass()->ShouldHaveEmbeddedImtAndVTable()) { 680 FixupClassVisitor visitor(this, copy); 681 orig->VisitReferences<true /*visit class*/>(visitor, visitor); 682 } else { 683 FixupVisitor visitor(this, copy); 684 orig->VisitReferences<true /*visit class*/>(visitor, visitor); 685 } 686 if (orig->IsArtMethod<kVerifyNone>()) { 687 FixupMethod(orig->AsArtMethod<kVerifyNone>(), down_cast<ArtMethod*>(copy)); 688 } 689} 690 691const byte* ImageWriter::GetQuickCode(mirror::ArtMethod* method, bool* quick_is_interpreted) { 692 DCHECK(!method->IsResolutionMethod() && !method->IsImtConflictMethod() && 693 !method->IsImtUnimplementedMethod() && !method->IsAbstract()) << PrettyMethod(method); 694 695 // Use original code if it exists. Otherwise, set the code pointer to the resolution 696 // trampoline. 697 698 // Quick entrypoint: 699 const byte* quick_code = GetOatAddress(method->GetQuickOatCodeOffset()); 700 *quick_is_interpreted = false; 701 if (quick_code != nullptr && 702 (!method->IsStatic() || method->IsConstructor() || method->GetDeclaringClass()->IsInitialized())) { 703 // We have code for a non-static or initialized method, just use the code. 704 } else if (quick_code == nullptr && method->IsNative() && 705 (!method->IsStatic() || method->GetDeclaringClass()->IsInitialized())) { 706 // Non-static or initialized native method missing compiled code, use generic JNI version. 707 quick_code = GetOatAddress(quick_generic_jni_trampoline_offset_); 708 } else if (quick_code == nullptr && !method->IsNative()) { 709 // We don't have code at all for a non-native method, use the interpreter. 710 quick_code = GetOatAddress(quick_to_interpreter_bridge_offset_); 711 *quick_is_interpreted = true; 712 } else { 713 CHECK(!method->GetDeclaringClass()->IsInitialized()); 714 // We have code for a static method, but need to go through the resolution stub for class 715 // initialization. 716 quick_code = GetOatAddress(quick_resolution_trampoline_offset_); 717 } 718 return quick_code; 719} 720 721const byte* ImageWriter::GetQuickEntryPoint(mirror::ArtMethod* method) { 722 // Calculate the quick entry point following the same logic as FixupMethod() below. 723 // The resolution method has a special trampoline to call. 724 Runtime* runtime = Runtime::Current(); 725 if (UNLIKELY(method == runtime->GetResolutionMethod())) { 726 return GetOatAddress(quick_resolution_trampoline_offset_); 727 } else if (UNLIKELY(method == runtime->GetImtConflictMethod() || 728 method == runtime->GetImtUnimplementedMethod())) { 729 return GetOatAddress(quick_imt_conflict_trampoline_offset_); 730 } else { 731 // We assume all methods have code. If they don't currently then we set them to the use the 732 // resolution trampoline. Abstract methods never have code and so we need to make sure their 733 // use results in an AbstractMethodError. We use the interpreter to achieve this. 734 if (UNLIKELY(method->IsAbstract())) { 735 return GetOatAddress(quick_to_interpreter_bridge_offset_); 736 } else { 737 bool quick_is_interpreted; 738 return GetQuickCode(method, &quick_is_interpreted); 739 } 740 } 741} 742 743void ImageWriter::FixupMethod(ArtMethod* orig, ArtMethod* copy) { 744 // OatWriter replaces the code_ with an offset value. Here we re-adjust to a pointer relative to 745 // oat_begin_ 746 747 // The resolution method has a special trampoline to call. 748 Runtime* runtime = Runtime::Current(); 749 if (UNLIKELY(orig == runtime->GetResolutionMethod())) { 750#if defined(ART_USE_PORTABLE_COMPILER) 751 copy->SetEntryPointFromPortableCompiledCode<kVerifyNone>(GetOatAddress(portable_resolution_trampoline_offset_)); 752#endif 753 copy->SetEntryPointFromQuickCompiledCode<kVerifyNone>(GetOatAddress(quick_resolution_trampoline_offset_)); 754 } else if (UNLIKELY(orig == runtime->GetImtConflictMethod() || 755 orig == runtime->GetImtUnimplementedMethod())) { 756#if defined(ART_USE_PORTABLE_COMPILER) 757 copy->SetEntryPointFromPortableCompiledCode<kVerifyNone>(GetOatAddress(portable_imt_conflict_trampoline_offset_)); 758#endif 759 copy->SetEntryPointFromQuickCompiledCode<kVerifyNone>(GetOatAddress(quick_imt_conflict_trampoline_offset_)); 760 } else { 761 // We assume all methods have code. If they don't currently then we set them to the use the 762 // resolution trampoline. Abstract methods never have code and so we need to make sure their 763 // use results in an AbstractMethodError. We use the interpreter to achieve this. 764 if (UNLIKELY(orig->IsAbstract())) { 765#if defined(ART_USE_PORTABLE_COMPILER) 766 copy->SetEntryPointFromPortableCompiledCode<kVerifyNone>(GetOatAddress(portable_to_interpreter_bridge_offset_)); 767#endif 768 copy->SetEntryPointFromQuickCompiledCode<kVerifyNone>(GetOatAddress(quick_to_interpreter_bridge_offset_)); 769 copy->SetEntryPointFromInterpreter<kVerifyNone>(reinterpret_cast<EntryPointFromInterpreter*> 770 (const_cast<byte*>(GetOatAddress(interpreter_to_interpreter_bridge_offset_)))); 771 } else { 772 bool quick_is_interpreted; 773 const byte* quick_code = GetQuickCode(orig, &quick_is_interpreted); 774 copy->SetEntryPointFromQuickCompiledCode<kVerifyNone>(quick_code); 775 776 // Portable entrypoint: 777 bool portable_is_interpreted = false; 778#if defined(ART_USE_PORTABLE_COMPILER) 779 const byte* portable_code = GetOatAddress(orig->GetPortableOatCodeOffset()); 780 if (portable_code != nullptr && 781 (!orig->IsStatic() || orig->IsConstructor() || orig->GetDeclaringClass()->IsInitialized())) { 782 // We have code for a non-static or initialized method, just use the code. 783 } else if (portable_code == nullptr && orig->IsNative() && 784 (!orig->IsStatic() || orig->GetDeclaringClass()->IsInitialized())) { 785 // Non-static or initialized native method missing compiled code, use generic JNI version. 786 // TODO: generic JNI support for LLVM. 787 portable_code = GetOatAddress(portable_resolution_trampoline_offset_); 788 } else if (portable_code == nullptr && !orig->IsNative()) { 789 // We don't have code at all for a non-native method, use the interpreter. 790 portable_code = GetOatAddress(portable_to_interpreter_bridge_offset_); 791 portable_is_interpreted = true; 792 } else { 793 CHECK(!orig->GetDeclaringClass()->IsInitialized()); 794 // We have code for a static method, but need to go through the resolution stub for class 795 // initialization. 796 portable_code = GetOatAddress(portable_resolution_trampoline_offset_); 797 } 798 copy->SetEntryPointFromPortableCompiledCode<kVerifyNone>(portable_code); 799#endif 800 // JNI entrypoint: 801 if (orig->IsNative()) { 802 // The native method's pointer is set to a stub to lookup via dlsym. 803 // Note this is not the code_ pointer, that is handled above. 804 copy->SetNativeMethod<kVerifyNone>(GetOatAddress(jni_dlsym_lookup_offset_)); 805 } else { 806 // Normal (non-abstract non-native) methods have various tables to relocate. 807 uint32_t native_gc_map_offset = orig->GetOatNativeGcMapOffset(); 808 const byte* native_gc_map = GetOatAddress(native_gc_map_offset); 809 copy->SetNativeGcMap<kVerifyNone>(reinterpret_cast<const uint8_t*>(native_gc_map)); 810 } 811 812 // Interpreter entrypoint: 813 // Set the interpreter entrypoint depending on whether there is compiled code or not. 814 uint32_t interpreter_code = (quick_is_interpreted && portable_is_interpreted) 815 ? interpreter_to_interpreter_bridge_offset_ 816 : interpreter_to_compiled_code_bridge_offset_; 817 copy->SetEntryPointFromInterpreter<kVerifyNone>( 818 reinterpret_cast<EntryPointFromInterpreter*>( 819 const_cast<byte*>(GetOatAddress(interpreter_code)))); 820 } 821 } 822} 823 824static OatHeader* GetOatHeaderFromElf(ElfFile* elf) { 825 Elf32_Shdr* data_sec = elf->FindSectionByName(".rodata"); 826 if (data_sec == nullptr) { 827 return nullptr; 828 } 829 return reinterpret_cast<OatHeader*>(elf->Begin() + data_sec->sh_offset); 830} 831 832void ImageWriter::PatchOatCodeAndMethods(File* elf_file) { 833 std::string error_msg; 834 std::unique_ptr<ElfFile> elf(ElfFile::Open(elf_file, PROT_READ|PROT_WRITE, 835 MAP_SHARED, &error_msg)); 836 if (elf.get() == nullptr) { 837 LOG(FATAL) << "Unable patch oat file: " << error_msg; 838 return; 839 } 840 if (!ElfPatcher::Patch(&compiler_driver_, elf.get(), oat_file_, 841 reinterpret_cast<uintptr_t>(oat_data_begin_), 842 GetImageAddressCallback, reinterpret_cast<void*>(this), 843 &error_msg)) { 844 LOG(FATAL) << "unable to patch oat file: " << error_msg; 845 return; 846 } 847 OatHeader* oat_header = GetOatHeaderFromElf(elf.get()); 848 CHECK(oat_header != nullptr); 849 CHECK(oat_header->IsValid()); 850 851 ImageHeader* image_header = reinterpret_cast<ImageHeader*>(image_->Begin()); 852 image_header->SetOatChecksum(oat_header->GetChecksum()); 853} 854 855} // namespace art 856