image_writer.cc revision 9433ec60b325b708b9fa87e699ab4a6565741494
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()); 147 148 // Before flushing, which might fail, release the mutator lock. 149 Thread::Current()->TransitionFromRunnableToSuspended(kNative); 150 151 if (oat_file->FlushCloseOrErase() != 0) { 152 LOG(ERROR) << "Failed to flush and close oat file " << oat_filename << " for " << oat_location; 153 return false; 154 } 155 156 std::unique_ptr<File> image_file(OS::CreateEmptyFile(image_filename.c_str())); 157 ImageHeader* image_header = reinterpret_cast<ImageHeader*>(image_->Begin()); 158 if (image_file.get() == NULL) { 159 LOG(ERROR) << "Failed to open image file " << image_filename; 160 return false; 161 } 162 if (fchmod(image_file->Fd(), 0644) != 0) { 163 PLOG(ERROR) << "Failed to make image file world readable: " << image_filename; 164 image_file->Erase(); 165 return EXIT_FAILURE; 166 } 167 168 // Write out the image. 169 CHECK_EQ(image_end_, image_header->GetImageSize()); 170 if (!image_file->WriteFully(image_->Begin(), image_end_)) { 171 PLOG(ERROR) << "Failed to write image file " << image_filename; 172 image_file->Erase(); 173 return false; 174 } 175 176 // Write out the image bitmap at the page aligned start of the image end. 177 CHECK_ALIGNED(image_header->GetImageBitmapOffset(), kPageSize); 178 if (!image_file->Write(reinterpret_cast<char*>(image_bitmap_->Begin()), 179 image_header->GetImageBitmapSize(), 180 image_header->GetImageBitmapOffset())) { 181 PLOG(ERROR) << "Failed to write image file " << image_filename; 182 image_file->Erase(); 183 return false; 184 } 185 186 if (image_file->FlushCloseOrErase() != 0) { 187 PLOG(ERROR) << "Failed to flush and close image file " << image_filename; 188 return false; 189 } 190 return true; 191} 192 193void ImageWriter::SetImageOffset(mirror::Object* object, size_t offset) { 194 DCHECK(object != nullptr); 195 DCHECK_NE(offset, 0U); 196 DCHECK(!IsImageOffsetAssigned(object)); 197 mirror::Object* obj = reinterpret_cast<mirror::Object*>(image_->Begin() + offset); 198 DCHECK_ALIGNED(obj, kObjectAlignment); 199 image_bitmap_->Set(obj); 200 // Before we stomp over the lock word, save the hash code for later. 201 Monitor::Deflate(Thread::Current(), object);; 202 LockWord lw(object->GetLockWord(false)); 203 switch (lw.GetState()) { 204 case LockWord::kFatLocked: { 205 LOG(FATAL) << "Fat locked object " << obj << " found during object copy"; 206 break; 207 } 208 case LockWord::kThinLocked: { 209 LOG(FATAL) << "Thin locked object " << obj << " found during object copy"; 210 break; 211 } 212 case LockWord::kUnlocked: 213 // No hash, don't need to save it. 214 break; 215 case LockWord::kHashCode: 216 saved_hashes_.push_back(std::make_pair(obj, lw.GetHashCode())); 217 break; 218 default: 219 LOG(FATAL) << "Unreachable."; 220 break; 221 } 222 object->SetLockWord(LockWord::FromForwardingAddress(offset), false); 223 DCHECK(IsImageOffsetAssigned(object)); 224} 225 226void ImageWriter::AssignImageOffset(mirror::Object* object) { 227 DCHECK(object != nullptr); 228 SetImageOffset(object, image_end_); 229 image_end_ += RoundUp(object->SizeOf(), 8); // 64-bit alignment 230 DCHECK_LT(image_end_, image_->Size()); 231} 232 233bool ImageWriter::IsImageOffsetAssigned(mirror::Object* object) const { 234 DCHECK(object != nullptr); 235 return object->GetLockWord(false).GetState() == LockWord::kForwardingAddress; 236} 237 238size_t ImageWriter::GetImageOffset(mirror::Object* object) const { 239 DCHECK(object != nullptr); 240 DCHECK(IsImageOffsetAssigned(object)); 241 LockWord lock_word = object->GetLockWord(false); 242 size_t offset = lock_word.ForwardingAddress(); 243 DCHECK_LT(offset, image_end_); 244 return offset; 245} 246 247bool ImageWriter::AllocMemory() { 248 size_t length = RoundUp(Runtime::Current()->GetHeap()->GetTotalMemory(), kPageSize); 249 std::string error_msg; 250 image_.reset(MemMap::MapAnonymous("image writer image", NULL, length, PROT_READ | PROT_WRITE, 251 true, &error_msg)); 252 if (UNLIKELY(image_.get() == nullptr)) { 253 LOG(ERROR) << "Failed to allocate memory for image file generation: " << error_msg; 254 return false; 255 } 256 257 // Create the image bitmap. 258 image_bitmap_.reset(gc::accounting::ContinuousSpaceBitmap::Create("image bitmap", image_->Begin(), 259 length)); 260 if (image_bitmap_.get() == nullptr) { 261 LOG(ERROR) << "Failed to allocate memory for image bitmap"; 262 return false; 263 } 264 return true; 265} 266 267void ImageWriter::ComputeLazyFieldsForImageClasses() { 268 ClassLinker* class_linker = Runtime::Current()->GetClassLinker(); 269 class_linker->VisitClassesWithoutClassesLock(ComputeLazyFieldsForClassesVisitor, NULL); 270} 271 272bool ImageWriter::ComputeLazyFieldsForClassesVisitor(Class* c, void* /*arg*/) { 273 Thread* self = Thread::Current(); 274 StackHandleScope<1> hs(self); 275 mirror::Class::ComputeName(hs.NewHandle(c)); 276 return true; 277} 278 279void ImageWriter::ComputeEagerResolvedStringsCallback(Object* obj, void* arg) { 280 if (!obj->GetClass()->IsStringClass()) { 281 return; 282 } 283 mirror::String* string = obj->AsString(); 284 const uint16_t* utf16_string = string->GetCharArray()->GetData() + string->GetOffset(); 285 ClassLinker* class_linker = Runtime::Current()->GetClassLinker(); 286 ReaderMutexLock mu(Thread::Current(), *class_linker->DexLock()); 287 size_t dex_cache_count = class_linker->GetDexCacheCount(); 288 for (size_t i = 0; i < dex_cache_count; ++i) { 289 DexCache* dex_cache = class_linker->GetDexCache(i); 290 const DexFile& dex_file = *dex_cache->GetDexFile(); 291 const DexFile::StringId* string_id; 292 if (UNLIKELY(string->GetLength() == 0)) { 293 string_id = dex_file.FindStringId(""); 294 } else { 295 string_id = dex_file.FindStringId(utf16_string); 296 } 297 if (string_id != nullptr) { 298 // This string occurs in this dex file, assign the dex cache entry. 299 uint32_t string_idx = dex_file.GetIndexForStringId(*string_id); 300 if (dex_cache->GetResolvedString(string_idx) == NULL) { 301 dex_cache->SetResolvedString(string_idx, string); 302 } 303 } 304 } 305} 306 307void ImageWriter::ComputeEagerResolvedStrings() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 308 ReaderMutexLock mu(Thread::Current(), *Locks::heap_bitmap_lock_); 309 Runtime::Current()->GetHeap()->VisitObjects(ComputeEagerResolvedStringsCallback, this); 310} 311 312bool ImageWriter::IsImageClass(Class* klass) { 313 std::string temp; 314 return compiler_driver_.IsImageClass(klass->GetDescriptor(&temp)); 315} 316 317struct NonImageClasses { 318 ImageWriter* image_writer; 319 std::set<std::string>* non_image_classes; 320}; 321 322void ImageWriter::PruneNonImageClasses() { 323 if (compiler_driver_.GetImageClasses() == NULL) { 324 return; 325 } 326 Runtime* runtime = Runtime::Current(); 327 ClassLinker* class_linker = runtime->GetClassLinker(); 328 329 // Make a list of classes we would like to prune. 330 std::set<std::string> non_image_classes; 331 NonImageClasses context; 332 context.image_writer = this; 333 context.non_image_classes = &non_image_classes; 334 class_linker->VisitClasses(NonImageClassesVisitor, &context); 335 336 // Remove the undesired classes from the class roots. 337 for (const std::string& it : non_image_classes) { 338 bool result = class_linker->RemoveClass(it.c_str(), NULL); 339 DCHECK(result); 340 } 341 342 // Clear references to removed classes from the DexCaches. 343 ArtMethod* resolution_method = runtime->GetResolutionMethod(); 344 ReaderMutexLock mu(Thread::Current(), *class_linker->DexLock()); 345 size_t dex_cache_count = class_linker->GetDexCacheCount(); 346 for (size_t idx = 0; idx < dex_cache_count; ++idx) { 347 DexCache* dex_cache = class_linker->GetDexCache(idx); 348 for (size_t i = 0; i < dex_cache->NumResolvedTypes(); i++) { 349 Class* klass = dex_cache->GetResolvedType(i); 350 if (klass != NULL && !IsImageClass(klass)) { 351 dex_cache->SetResolvedType(i, NULL); 352 } 353 } 354 for (size_t i = 0; i < dex_cache->NumResolvedMethods(); i++) { 355 ArtMethod* method = dex_cache->GetResolvedMethod(i); 356 if (method != NULL && !IsImageClass(method->GetDeclaringClass())) { 357 dex_cache->SetResolvedMethod(i, resolution_method); 358 } 359 } 360 for (size_t i = 0; i < dex_cache->NumResolvedFields(); i++) { 361 ArtField* field = dex_cache->GetResolvedField(i); 362 if (field != NULL && !IsImageClass(field->GetDeclaringClass())) { 363 dex_cache->SetResolvedField(i, NULL); 364 } 365 } 366 } 367} 368 369bool ImageWriter::NonImageClassesVisitor(Class* klass, void* arg) { 370 NonImageClasses* context = reinterpret_cast<NonImageClasses*>(arg); 371 if (!context->image_writer->IsImageClass(klass)) { 372 std::string temp; 373 context->non_image_classes->insert(klass->GetDescriptor(&temp)); 374 } 375 return true; 376} 377 378void ImageWriter::CheckNonImageClassesRemoved() 379 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 380 if (compiler_driver_.GetImageClasses() != nullptr) { 381 gc::Heap* heap = Runtime::Current()->GetHeap(); 382 ReaderMutexLock mu(Thread::Current(), *Locks::heap_bitmap_lock_); 383 heap->VisitObjects(CheckNonImageClassesRemovedCallback, this); 384 } 385} 386 387void ImageWriter::CheckNonImageClassesRemovedCallback(Object* obj, void* arg) { 388 ImageWriter* image_writer = reinterpret_cast<ImageWriter*>(arg); 389 if (obj->IsClass()) { 390 Class* klass = obj->AsClass(); 391 if (!image_writer->IsImageClass(klass)) { 392 image_writer->DumpImageClasses(); 393 std::string temp; 394 CHECK(image_writer->IsImageClass(klass)) << klass->GetDescriptor(&temp) 395 << " " << PrettyDescriptor(klass); 396 } 397 } 398} 399 400void ImageWriter::DumpImageClasses() { 401 const std::set<std::string>* image_classes = compiler_driver_.GetImageClasses(); 402 CHECK(image_classes != NULL); 403 for (const std::string& image_class : *image_classes) { 404 LOG(INFO) << " " << image_class; 405 } 406} 407 408void ImageWriter::CalculateObjectOffsets(Object* obj) { 409 DCHECK(obj != NULL); 410 // if it is a string, we want to intern it if its not interned. 411 if (obj->GetClass()->IsStringClass()) { 412 // we must be an interned string that was forward referenced and already assigned 413 if (IsImageOffsetAssigned(obj)) { 414 DCHECK_EQ(obj, obj->AsString()->Intern()); 415 return; 416 } 417 mirror::String* const interned = obj->AsString()->Intern(); 418 if (obj != interned) { 419 if (!IsImageOffsetAssigned(interned)) { 420 // interned obj is after us, allocate its location early 421 AssignImageOffset(interned); 422 } 423 // point those looking for this object to the interned version. 424 SetImageOffset(obj, GetImageOffset(interned)); 425 return; 426 } 427 // else (obj == interned), nothing to do but fall through to the normal case 428 } 429 430 AssignImageOffset(obj); 431} 432 433ObjectArray<Object>* ImageWriter::CreateImageRoots() const { 434 Runtime* runtime = Runtime::Current(); 435 ClassLinker* class_linker = runtime->GetClassLinker(); 436 Thread* self = Thread::Current(); 437 StackHandleScope<3> hs(self); 438 Handle<Class> object_array_class(hs.NewHandle( 439 class_linker->FindSystemClass(self, "[Ljava/lang/Object;"))); 440 441 // build an Object[] of all the DexCaches used in the source_space_. 442 // Since we can't hold the dex lock when allocating the dex_caches 443 // ObjectArray, we lock the dex lock twice, first to get the number 444 // of dex caches first and then lock it again to copy the dex 445 // caches. We check that the number of dex caches does not change. 446 size_t dex_cache_count; 447 { 448 ReaderMutexLock mu(Thread::Current(), *class_linker->DexLock()); 449 dex_cache_count = class_linker->GetDexCacheCount(); 450 } 451 Handle<ObjectArray<Object>> dex_caches( 452 hs.NewHandle(ObjectArray<Object>::Alloc(self, object_array_class.Get(), 453 dex_cache_count))); 454 CHECK(dex_caches.Get() != nullptr) << "Failed to allocate a dex cache array."; 455 { 456 ReaderMutexLock mu(Thread::Current(), *class_linker->DexLock()); 457 CHECK_EQ(dex_cache_count, class_linker->GetDexCacheCount()) 458 << "The number of dex caches changed."; 459 for (size_t i = 0; i < dex_cache_count; ++i) { 460 dex_caches->Set<false>(i, class_linker->GetDexCache(i)); 461 } 462 } 463 464 // build an Object[] of the roots needed to restore the runtime 465 Handle<ObjectArray<Object>> image_roots(hs.NewHandle( 466 ObjectArray<Object>::Alloc(self, object_array_class.Get(), ImageHeader::kImageRootsMax))); 467 image_roots->Set<false>(ImageHeader::kResolutionMethod, runtime->GetResolutionMethod()); 468 image_roots->Set<false>(ImageHeader::kImtConflictMethod, runtime->GetImtConflictMethod()); 469 image_roots->Set<false>(ImageHeader::kImtUnimplementedMethod, 470 runtime->GetImtUnimplementedMethod()); 471 image_roots->Set<false>(ImageHeader::kDefaultImt, runtime->GetDefaultImt()); 472 image_roots->Set<false>(ImageHeader::kCalleeSaveMethod, 473 runtime->GetCalleeSaveMethod(Runtime::kSaveAll)); 474 image_roots->Set<false>(ImageHeader::kRefsOnlySaveMethod, 475 runtime->GetCalleeSaveMethod(Runtime::kRefsOnly)); 476 image_roots->Set<false>(ImageHeader::kRefsAndArgsSaveMethod, 477 runtime->GetCalleeSaveMethod(Runtime::kRefsAndArgs)); 478 image_roots->Set<false>(ImageHeader::kDexCaches, dex_caches.Get()); 479 image_roots->Set<false>(ImageHeader::kClassRoots, class_linker->GetClassRoots()); 480 for (int i = 0; i < ImageHeader::kImageRootsMax; i++) { 481 CHECK(image_roots->Get(i) != NULL); 482 } 483 return image_roots.Get(); 484} 485 486// Walk instance fields of the given Class. Separate function to allow recursion on the super 487// class. 488void ImageWriter::WalkInstanceFields(mirror::Object* obj, mirror::Class* klass) { 489 // Visit fields of parent classes first. 490 StackHandleScope<1> hs(Thread::Current()); 491 Handle<mirror::Class> h_class(hs.NewHandle(klass)); 492 mirror::Class* super = h_class->GetSuperClass(); 493 if (super != nullptr) { 494 WalkInstanceFields(obj, super); 495 } 496 // 497 size_t num_reference_fields = h_class->NumReferenceInstanceFields(); 498 MemberOffset field_offset = h_class->GetFirstReferenceInstanceFieldOffset(); 499 for (size_t i = 0; i < num_reference_fields; ++i) { 500 mirror::Object* value = obj->GetFieldObject<mirror::Object>(field_offset); 501 if (value != nullptr) { 502 WalkFieldsInOrder(value); 503 } 504 field_offset = MemberOffset(field_offset.Uint32Value() + 505 sizeof(mirror::HeapReference<mirror::Object>)); 506 } 507} 508 509// For an unvisited object, visit it then all its children found via fields. 510void ImageWriter::WalkFieldsInOrder(mirror::Object* obj) { 511 if (!IsImageOffsetAssigned(obj)) { 512 // Walk instance fields of all objects 513 StackHandleScope<2> hs(Thread::Current()); 514 Handle<mirror::Object> h_obj(hs.NewHandle(obj)); 515 Handle<mirror::Class> klass(hs.NewHandle(obj->GetClass())); 516 // visit the object itself. 517 CalculateObjectOffsets(h_obj.Get()); 518 WalkInstanceFields(h_obj.Get(), klass.Get()); 519 // Walk static fields of a Class. 520 if (h_obj->IsClass()) { 521 size_t num_static_fields = klass->NumReferenceStaticFields(); 522 MemberOffset field_offset = klass->GetFirstReferenceStaticFieldOffset(); 523 for (size_t i = 0; i < num_static_fields; ++i) { 524 mirror::Object* value = h_obj->GetFieldObject<mirror::Object>(field_offset); 525 if (value != nullptr) { 526 WalkFieldsInOrder(value); 527 } 528 field_offset = MemberOffset(field_offset.Uint32Value() + 529 sizeof(mirror::HeapReference<mirror::Object>)); 530 } 531 } else if (h_obj->IsObjectArray()) { 532 // Walk elements of an object array. 533 int32_t length = h_obj->AsObjectArray<mirror::Object>()->GetLength(); 534 for (int32_t i = 0; i < length; i++) { 535 mirror::ObjectArray<mirror::Object>* obj_array = h_obj->AsObjectArray<mirror::Object>(); 536 mirror::Object* value = obj_array->Get(i); 537 if (value != nullptr) { 538 WalkFieldsInOrder(value); 539 } 540 } 541 } 542 } 543} 544 545void ImageWriter::WalkFieldsCallback(mirror::Object* obj, void* arg) { 546 ImageWriter* writer = reinterpret_cast<ImageWriter*>(arg); 547 DCHECK(writer != nullptr); 548 writer->WalkFieldsInOrder(obj); 549} 550 551void ImageWriter::CalculateNewObjectOffsets(size_t oat_loaded_size, size_t oat_data_offset) { 552 CHECK_NE(0U, oat_loaded_size); 553 Thread* self = Thread::Current(); 554 StackHandleScope<1> hs(self); 555 Handle<ObjectArray<Object>> image_roots(hs.NewHandle(CreateImageRoots())); 556 557 gc::Heap* heap = Runtime::Current()->GetHeap(); 558 DCHECK_EQ(0U, image_end_); 559 560 // Leave space for the header, but do not write it yet, we need to 561 // know where image_roots is going to end up 562 image_end_ += RoundUp(sizeof(ImageHeader), 8); // 64-bit-alignment 563 564 { 565 WriterMutexLock mu(self, *Locks::heap_bitmap_lock_); 566 // TODO: Image spaces only? 567 const char* old = self->StartAssertNoThreadSuspension("ImageWriter"); 568 DCHECK_LT(image_end_, image_->Size()); 569 // Clear any pre-existing monitors which may have been in the monitor words. 570 heap->VisitObjects(WalkFieldsCallback, this); 571 self->EndAssertNoThreadSuspension(old); 572 } 573 574 const byte* oat_file_begin = image_begin_ + RoundUp(image_end_, kPageSize); 575 const byte* oat_file_end = oat_file_begin + oat_loaded_size; 576 oat_data_begin_ = oat_file_begin + oat_data_offset; 577 const byte* oat_data_end = oat_data_begin_ + oat_file_->Size(); 578 579 // Return to write header at start of image with future location of image_roots. At this point, 580 // image_end_ is the size of the image (excluding bitmaps). 581 const size_t heap_bytes_per_bitmap_byte = kBitsPerByte * kObjectAlignment; 582 const size_t bitmap_bytes = RoundUp(image_end_, heap_bytes_per_bitmap_byte) / 583 heap_bytes_per_bitmap_byte; 584 ImageHeader image_header(PointerToLowMemUInt32(image_begin_), 585 static_cast<uint32_t>(image_end_), 586 RoundUp(image_end_, kPageSize), 587 RoundUp(bitmap_bytes, kPageSize), 588 PointerToLowMemUInt32(GetImageAddress(image_roots.Get())), 589 oat_file_->GetOatHeader().GetChecksum(), 590 PointerToLowMemUInt32(oat_file_begin), 591 PointerToLowMemUInt32(oat_data_begin_), 592 PointerToLowMemUInt32(oat_data_end), 593 PointerToLowMemUInt32(oat_file_end), 594 compile_pic_); 595 memcpy(image_->Begin(), &image_header, sizeof(image_header)); 596 597 // Note that image_end_ is left at end of used space 598} 599 600void ImageWriter::CopyAndFixupObjects() 601 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 602 Thread* self = Thread::Current(); 603 const char* old_cause = self->StartAssertNoThreadSuspension("ImageWriter"); 604 gc::Heap* heap = Runtime::Current()->GetHeap(); 605 // TODO: heap validation can't handle this fix up pass 606 heap->DisableObjectValidation(); 607 // TODO: Image spaces only? 608 WriterMutexLock mu(self, *Locks::heap_bitmap_lock_); 609 heap->VisitObjects(CopyAndFixupObjectsCallback, this); 610 // Fix up the object previously had hash codes. 611 for (const std::pair<mirror::Object*, uint32_t>& hash_pair : saved_hashes_) { 612 hash_pair.first->SetLockWord(LockWord::FromHashCode(hash_pair.second), false); 613 } 614 saved_hashes_.clear(); 615 self->EndAssertNoThreadSuspension(old_cause); 616} 617 618void ImageWriter::CopyAndFixupObjectsCallback(Object* obj, void* arg) { 619 DCHECK(obj != nullptr); 620 DCHECK(arg != nullptr); 621 ImageWriter* image_writer = reinterpret_cast<ImageWriter*>(arg); 622 // see GetLocalAddress for similar computation 623 size_t offset = image_writer->GetImageOffset(obj); 624 byte* dst = image_writer->image_->Begin() + offset; 625 const byte* src = reinterpret_cast<const byte*>(obj); 626 size_t n = obj->SizeOf(); 627 DCHECK_LT(offset + n, image_writer->image_->Size()); 628 memcpy(dst, src, n); 629 Object* copy = reinterpret_cast<Object*>(dst); 630 // Write in a hash code of objects which have inflated monitors or a hash code in their monitor 631 // word. 632 copy->SetLockWord(LockWord(), false); 633 image_writer->FixupObject(obj, copy); 634} 635 636class FixupVisitor { 637 public: 638 FixupVisitor(ImageWriter* image_writer, Object* copy) : image_writer_(image_writer), copy_(copy) { 639 } 640 641 void operator()(Object* obj, MemberOffset offset, bool /*is_static*/) const 642 EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_, Locks::heap_bitmap_lock_) { 643 Object* ref = obj->GetFieldObject<Object, kVerifyNone>(offset); 644 // Use SetFieldObjectWithoutWriteBarrier to avoid card marking since we are writing to the 645 // image. 646 copy_->SetFieldObjectWithoutWriteBarrier<false, true, kVerifyNone>( 647 offset, image_writer_->GetImageAddress(ref)); 648 } 649 650 // java.lang.ref.Reference visitor. 651 void operator()(mirror::Class* /*klass*/, mirror::Reference* ref) const 652 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) 653 EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) { 654 copy_->SetFieldObjectWithoutWriteBarrier<false, true, kVerifyNone>( 655 mirror::Reference::ReferentOffset(), image_writer_->GetImageAddress(ref->GetReferent())); 656 } 657 658 protected: 659 ImageWriter* const image_writer_; 660 mirror::Object* const copy_; 661}; 662 663class FixupClassVisitor FINAL : public FixupVisitor { 664 public: 665 FixupClassVisitor(ImageWriter* image_writer, Object* copy) : FixupVisitor(image_writer, copy) { 666 } 667 668 void operator()(Object* obj, MemberOffset offset, bool /*is_static*/) const 669 EXCLUSIVE_LOCKS_REQUIRED(Locks::mutator_lock_, Locks::heap_bitmap_lock_) { 670 DCHECK(obj->IsClass()); 671 FixupVisitor::operator()(obj, offset, false); 672 673 if (offset.Uint32Value() < mirror::Class::EmbeddedVTableOffset().Uint32Value()) { 674 return; 675 } 676 } 677 678 void operator()(mirror::Class* /*klass*/, mirror::Reference* ref) const 679 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) 680 EXCLUSIVE_LOCKS_REQUIRED(Locks::heap_bitmap_lock_) { 681 LOG(FATAL) << "Reference not expected here."; 682 } 683}; 684 685void ImageWriter::FixupObject(Object* orig, Object* copy) { 686 DCHECK(orig != nullptr); 687 DCHECK(copy != nullptr); 688 if (kUseBakerOrBrooksReadBarrier) { 689 orig->AssertReadBarrierPointer(); 690 if (kUseBrooksReadBarrier) { 691 // Note the address 'copy' isn't the same as the image address of 'orig'. 692 copy->SetReadBarrierPointer(GetImageAddress(orig)); 693 DCHECK_EQ(copy->GetReadBarrierPointer(), GetImageAddress(orig)); 694 } 695 } 696 if (orig->IsClass() && orig->AsClass()->ShouldHaveEmbeddedImtAndVTable()) { 697 FixupClassVisitor visitor(this, copy); 698 orig->VisitReferences<true /*visit class*/>(visitor, visitor); 699 } else { 700 FixupVisitor visitor(this, copy); 701 orig->VisitReferences<true /*visit class*/>(visitor, visitor); 702 } 703 if (orig->IsArtMethod<kVerifyNone>()) { 704 FixupMethod(orig->AsArtMethod<kVerifyNone>(), down_cast<ArtMethod*>(copy)); 705 } 706} 707 708const byte* ImageWriter::GetQuickCode(mirror::ArtMethod* method, bool* quick_is_interpreted) { 709 DCHECK(!method->IsResolutionMethod() && !method->IsImtConflictMethod() && 710 !method->IsImtUnimplementedMethod() && !method->IsAbstract()) << PrettyMethod(method); 711 712 // Use original code if it exists. Otherwise, set the code pointer to the resolution 713 // trampoline. 714 715 // Quick entrypoint: 716 const byte* quick_code = GetOatAddress(method->GetQuickOatCodeOffset()); 717 *quick_is_interpreted = false; 718 if (quick_code != nullptr && 719 (!method->IsStatic() || method->IsConstructor() || method->GetDeclaringClass()->IsInitialized())) { 720 // We have code for a non-static or initialized method, just use the code. 721 } else if (quick_code == nullptr && method->IsNative() && 722 (!method->IsStatic() || method->GetDeclaringClass()->IsInitialized())) { 723 // Non-static or initialized native method missing compiled code, use generic JNI version. 724 quick_code = GetOatAddress(quick_generic_jni_trampoline_offset_); 725 } else if (quick_code == nullptr && !method->IsNative()) { 726 // We don't have code at all for a non-native method, use the interpreter. 727 quick_code = GetOatAddress(quick_to_interpreter_bridge_offset_); 728 *quick_is_interpreted = true; 729 } else { 730 CHECK(!method->GetDeclaringClass()->IsInitialized()); 731 // We have code for a static method, but need to go through the resolution stub for class 732 // initialization. 733 quick_code = GetOatAddress(quick_resolution_trampoline_offset_); 734 } 735 return quick_code; 736} 737 738const byte* ImageWriter::GetQuickEntryPoint(mirror::ArtMethod* method) { 739 // Calculate the quick entry point following the same logic as FixupMethod() below. 740 // The resolution method has a special trampoline to call. 741 Runtime* runtime = Runtime::Current(); 742 if (UNLIKELY(method == runtime->GetResolutionMethod())) { 743 return GetOatAddress(quick_resolution_trampoline_offset_); 744 } else if (UNLIKELY(method == runtime->GetImtConflictMethod() || 745 method == runtime->GetImtUnimplementedMethod())) { 746 return GetOatAddress(quick_imt_conflict_trampoline_offset_); 747 } else { 748 // We assume all methods have code. If they don't currently then we set them to the use the 749 // resolution trampoline. Abstract methods never have code and so we need to make sure their 750 // use results in an AbstractMethodError. We use the interpreter to achieve this. 751 if (UNLIKELY(method->IsAbstract())) { 752 return GetOatAddress(quick_to_interpreter_bridge_offset_); 753 } else { 754 bool quick_is_interpreted; 755 return GetQuickCode(method, &quick_is_interpreted); 756 } 757 } 758} 759 760void ImageWriter::FixupMethod(ArtMethod* orig, ArtMethod* copy) { 761 // OatWriter replaces the code_ with an offset value. Here we re-adjust to a pointer relative to 762 // oat_begin_ 763 764 // The resolution method has a special trampoline to call. 765 Runtime* runtime = Runtime::Current(); 766 if (UNLIKELY(orig == runtime->GetResolutionMethod())) { 767#if defined(ART_USE_PORTABLE_COMPILER) 768 copy->SetEntryPointFromPortableCompiledCode<kVerifyNone>(GetOatAddress(portable_resolution_trampoline_offset_)); 769#endif 770 copy->SetEntryPointFromQuickCompiledCode<kVerifyNone>(GetOatAddress(quick_resolution_trampoline_offset_)); 771 } else if (UNLIKELY(orig == runtime->GetImtConflictMethod() || 772 orig == runtime->GetImtUnimplementedMethod())) { 773#if defined(ART_USE_PORTABLE_COMPILER) 774 copy->SetEntryPointFromPortableCompiledCode<kVerifyNone>(GetOatAddress(portable_imt_conflict_trampoline_offset_)); 775#endif 776 copy->SetEntryPointFromQuickCompiledCode<kVerifyNone>(GetOatAddress(quick_imt_conflict_trampoline_offset_)); 777 } else { 778 // We assume all methods have code. If they don't currently then we set them to the use the 779 // resolution trampoline. Abstract methods never have code and so we need to make sure their 780 // use results in an AbstractMethodError. We use the interpreter to achieve this. 781 if (UNLIKELY(orig->IsAbstract())) { 782#if defined(ART_USE_PORTABLE_COMPILER) 783 copy->SetEntryPointFromPortableCompiledCode<kVerifyNone>(GetOatAddress(portable_to_interpreter_bridge_offset_)); 784#endif 785 copy->SetEntryPointFromQuickCompiledCode<kVerifyNone>(GetOatAddress(quick_to_interpreter_bridge_offset_)); 786 copy->SetEntryPointFromInterpreter<kVerifyNone>(reinterpret_cast<EntryPointFromInterpreter*> 787 (const_cast<byte*>(GetOatAddress(interpreter_to_interpreter_bridge_offset_)))); 788 } else { 789 bool quick_is_interpreted; 790 const byte* quick_code = GetQuickCode(orig, &quick_is_interpreted); 791 copy->SetEntryPointFromQuickCompiledCode<kVerifyNone>(quick_code); 792 793 // Portable entrypoint: 794 bool portable_is_interpreted = false; 795#if defined(ART_USE_PORTABLE_COMPILER) 796 const byte* portable_code = GetOatAddress(orig->GetPortableOatCodeOffset()); 797 if (portable_code != nullptr && 798 (!orig->IsStatic() || orig->IsConstructor() || orig->GetDeclaringClass()->IsInitialized())) { 799 // We have code for a non-static or initialized method, just use the code. 800 } else if (portable_code == nullptr && orig->IsNative() && 801 (!orig->IsStatic() || orig->GetDeclaringClass()->IsInitialized())) { 802 // Non-static or initialized native method missing compiled code, use generic JNI version. 803 // TODO: generic JNI support for LLVM. 804 portable_code = GetOatAddress(portable_resolution_trampoline_offset_); 805 } else if (portable_code == nullptr && !orig->IsNative()) { 806 // We don't have code at all for a non-native method, use the interpreter. 807 portable_code = GetOatAddress(portable_to_interpreter_bridge_offset_); 808 portable_is_interpreted = true; 809 } else { 810 CHECK(!orig->GetDeclaringClass()->IsInitialized()); 811 // We have code for a static method, but need to go through the resolution stub for class 812 // initialization. 813 portable_code = GetOatAddress(portable_resolution_trampoline_offset_); 814 } 815 copy->SetEntryPointFromPortableCompiledCode<kVerifyNone>(portable_code); 816#endif 817 // JNI entrypoint: 818 if (orig->IsNative()) { 819 // The native method's pointer is set to a stub to lookup via dlsym. 820 // Note this is not the code_ pointer, that is handled above. 821 copy->SetNativeMethod<kVerifyNone>(GetOatAddress(jni_dlsym_lookup_offset_)); 822 } else { 823 // Normal (non-abstract non-native) methods have various tables to relocate. 824 uint32_t native_gc_map_offset = orig->GetOatNativeGcMapOffset(); 825 const byte* native_gc_map = GetOatAddress(native_gc_map_offset); 826 copy->SetNativeGcMap<kVerifyNone>(reinterpret_cast<const uint8_t*>(native_gc_map)); 827 } 828 829 // Interpreter entrypoint: 830 // Set the interpreter entrypoint depending on whether there is compiled code or not. 831 uint32_t interpreter_code = (quick_is_interpreted && portable_is_interpreted) 832 ? interpreter_to_interpreter_bridge_offset_ 833 : interpreter_to_compiled_code_bridge_offset_; 834 copy->SetEntryPointFromInterpreter<kVerifyNone>( 835 reinterpret_cast<EntryPointFromInterpreter*>( 836 const_cast<byte*>(GetOatAddress(interpreter_code)))); 837 } 838 } 839} 840 841static OatHeader* GetOatHeaderFromElf(ElfFile* elf) { 842 Elf32_Shdr* data_sec = elf->FindSectionByName(".rodata"); 843 if (data_sec == nullptr) { 844 return nullptr; 845 } 846 return reinterpret_cast<OatHeader*>(elf->Begin() + data_sec->sh_offset); 847} 848 849void ImageWriter::PatchOatCodeAndMethods(File* elf_file) { 850 std::string error_msg; 851 std::unique_ptr<ElfFile> elf(ElfFile::Open(elf_file, PROT_READ|PROT_WRITE, 852 MAP_SHARED, &error_msg)); 853 if (elf.get() == nullptr) { 854 LOG(FATAL) << "Unable patch oat file: " << error_msg; 855 return; 856 } 857 if (!ElfPatcher::Patch(&compiler_driver_, elf.get(), oat_file_, 858 reinterpret_cast<uintptr_t>(oat_data_begin_), 859 GetImageAddressCallback, reinterpret_cast<void*>(this), 860 &error_msg)) { 861 LOG(FATAL) << "unable to patch oat file: " << error_msg; 862 return; 863 } 864 OatHeader* oat_header = GetOatHeaderFromElf(elf.get()); 865 CHECK(oat_header != nullptr); 866 CHECK(oat_header->IsValid()); 867 868 ImageHeader* image_header = reinterpret_cast<ImageHeader*>(image_->Begin()); 869 image_header->SetOatChecksum(oat_header->GetChecksum()); 870} 871 872} // namespace art 873