image_writer.cc revision 590fee9e8972f872301c2d16a575d579ee564bee 
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 <vector>
22
23#include "base/logging.h"
24#include "base/unix_file/fd_file.h"
25#include "class_linker.h"
26#include "compiled_method.h"
27#include "dex_file-inl.h"
28#include "driver/compiler_driver.h"
29#include "elf_writer.h"
30#include "gc/accounting/card_table-inl.h"
31#include "gc/accounting/heap_bitmap.h"
32#include "gc/accounting/space_bitmap-inl.h"
33#include "gc/heap.h"
34#include "gc/space/large_object_space.h"
35#include "gc/space/space-inl.h"
36#include "globals.h"
37#include "image.h"
38#include "intern_table.h"
39#include "lock_word.h"
40#include "mirror/art_field-inl.h"
41#include "mirror/art_method-inl.h"
42#include "mirror/array-inl.h"
43#include "mirror/class-inl.h"
44#include "mirror/class_loader.h"
45#include "mirror/dex_cache-inl.h"
46#include "mirror/object-inl.h"
47#include "mirror/object_array-inl.h"
48#include "oat.h"
49#include "oat_file.h"
50#include "object_utils.h"
51#include "runtime.h"
52#include "scoped_thread_state_change.h"
53#include "sirt_ref.h"
54#include "UniquePtr.h"
55#include "utils.h"
56
57using ::art::mirror::ArtField;
58using ::art::mirror::ArtMethod;
59using ::art::mirror::Class;
60using ::art::mirror::DexCache;
61using ::art::mirror::EntryPointFromInterpreter;
62using ::art::mirror::Object;
63using ::art::mirror::ObjectArray;
64using ::art::mirror::String;
65
66namespace art {
67
68bool ImageWriter::Write(const std::string& image_filename,
69                        uintptr_t image_begin,
70                        const std::string& oat_filename,
71                        const std::string& oat_location) {
72  CHECK(!image_filename.empty());
73
74  CHECK_NE(image_begin, 0U);
75  image_begin_ = reinterpret_cast<byte*>(image_begin);
76
77  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
78
79  UniquePtr<File> oat_file(OS::OpenFileReadWrite(oat_filename.c_str()));
80  if (oat_file.get() == NULL) {
81    LOG(ERROR) << "Failed to open oat file " << oat_filename << " for " << oat_location;
82    return false;
83  }
84  std::string error_msg;
85  oat_file_ = OatFile::OpenWritable(oat_file.get(), oat_location, &error_msg);
86  if (oat_file_ == nullptr) {
87    LOG(ERROR) << "Failed to open writable oat file " << oat_filename << " for " << oat_location
88        << ": " << error_msg;
89    return false;
90  }
91  CHECK_EQ(class_linker->RegisterOatFile(oat_file_), oat_file_);
92
93  interpreter_to_interpreter_bridge_offset_ =
94      oat_file_->GetOatHeader().GetInterpreterToInterpreterBridgeOffset();
95  interpreter_to_compiled_code_bridge_offset_ =
96      oat_file_->GetOatHeader().GetInterpreterToCompiledCodeBridgeOffset();
97
98  jni_dlsym_lookup_offset_ = oat_file_->GetOatHeader().GetJniDlsymLookupOffset();
99
100  portable_imt_conflict_trampoline_offset_ =
101      oat_file_->GetOatHeader().GetPortableImtConflictTrampolineOffset();
102  portable_resolution_trampoline_offset_ =
103      oat_file_->GetOatHeader().GetPortableResolutionTrampolineOffset();
104  portable_to_interpreter_bridge_offset_ =
105      oat_file_->GetOatHeader().GetPortableToInterpreterBridgeOffset();
106
107  quick_imt_conflict_trampoline_offset_ =
108      oat_file_->GetOatHeader().GetQuickImtConflictTrampolineOffset();
109  quick_resolution_trampoline_offset_ =
110      oat_file_->GetOatHeader().GetQuickResolutionTrampolineOffset();
111  quick_to_interpreter_bridge_offset_ =
112      oat_file_->GetOatHeader().GetQuickToInterpreterBridgeOffset();
113  {
114    Thread::Current()->TransitionFromSuspendedToRunnable();
115    PruneNonImageClasses();  // Remove junk
116    ComputeLazyFieldsForImageClasses();  // Add useful information
117    ComputeEagerResolvedStrings();
118    Thread::Current()->TransitionFromRunnableToSuspended(kNative);
119  }
120  gc::Heap* heap = Runtime::Current()->GetHeap();
121  heap->CollectGarbage(false);  // Remove garbage.
122
123  if (!AllocMemory()) {
124    return false;
125  }
126
127  if (kIsDebugBuild) {
128    ScopedObjectAccess soa(Thread::Current());
129    CheckNonImageClassesRemoved();
130  }
131
132  Thread::Current()->TransitionFromSuspendedToRunnable();
133  size_t oat_loaded_size = 0;
134  size_t oat_data_offset = 0;
135  ElfWriter::GetOatElfInformation(oat_file.get(), oat_loaded_size, oat_data_offset);
136  CalculateNewObjectOffsets(oat_loaded_size, oat_data_offset);
137  CopyAndFixupObjects();
138  PatchOatCodeAndMethods();
139  Thread::Current()->TransitionFromRunnableToSuspended(kNative);
140
141  UniquePtr<File> image_file(OS::CreateEmptyFile(image_filename.c_str()));
142  ImageHeader* image_header = reinterpret_cast<ImageHeader*>(image_->Begin());
143  if (image_file.get() == NULL) {
144    LOG(ERROR) << "Failed to open image file " << image_filename;
145    return false;
146  }
147  if (fchmod(image_file->Fd(), 0644) != 0) {
148    PLOG(ERROR) << "Failed to make image file world readable: " << image_filename;
149    return EXIT_FAILURE;
150  }
151
152  // Write out the image.
153  CHECK_EQ(image_end_, image_header->GetImageSize());
154  if (!image_file->WriteFully(image_->Begin(), image_end_)) {
155    PLOG(ERROR) << "Failed to write image file " << image_filename;
156    return false;
157  }
158
159  // Write out the image bitmap at the page aligned start of the image end.
160  CHECK_ALIGNED(image_header->GetImageBitmapOffset(), kPageSize);
161  if (!image_file->Write(reinterpret_cast<char*>(image_bitmap_->Begin()),
162                         image_header->GetImageBitmapSize(),
163                         image_header->GetImageBitmapOffset())) {
164    PLOG(ERROR) << "Failed to write image file " << image_filename;
165    return false;
166  }
167
168  return true;
169}
170
171void ImageWriter::SetImageOffset(mirror::Object* object, size_t offset) {
172  DCHECK(object != nullptr);
173  DCHECK_NE(offset, 0U);
174  DCHECK(!IsImageOffsetAssigned(object));
175  mirror::Object* obj = reinterpret_cast<mirror::Object*>(image_->Begin() + offset);
176  DCHECK_ALIGNED(obj, kObjectAlignment);
177  image_bitmap_->Set(obj);
178  // Before we stomp over the lock word, save the hash code for later.
179  Monitor::Deflate(Thread::Current(), object);;
180  LockWord lw(object->GetLockWord());
181  switch (lw.GetState()) {
182    case LockWord::kFatLocked: {
183      LOG(FATAL) << "Fat locked object " << obj << " found during object copy";
184      break;
185    }
186    case LockWord::kThinLocked: {
187      LOG(FATAL) << "Thin locked object " << obj << " found during object copy";
188      break;
189    }
190    case LockWord::kUnlocked:
191      // No hash, don't need to save it.
192      break;
193    case LockWord::kHashCode:
194      saved_hashes_.push_back(std::make_pair(obj, lw.GetHashCode()));
195      break;
196    default:
197      LOG(FATAL) << "Unreachable.";
198      break;
199  }
200  object->SetLockWord(LockWord::FromForwardingAddress(offset));
201  DCHECK(IsImageOffsetAssigned(object));
202}
203
204void ImageWriter::AssignImageOffset(mirror::Object* object) {
205  DCHECK(object != nullptr);
206  SetImageOffset(object, image_end_);
207  image_end_ += RoundUp(object->SizeOf(), 8);  // 64-bit alignment
208  DCHECK_LT(image_end_, image_->Size());
209}
210
211bool ImageWriter::IsImageOffsetAssigned(const mirror::Object* object) const {
212  DCHECK(object != nullptr);
213  return object->GetLockWord().GetState() == LockWord::kForwardingAddress;
214}
215
216size_t ImageWriter::GetImageOffset(const mirror::Object* object) const {
217  DCHECK(object != nullptr);
218  DCHECK(IsImageOffsetAssigned(object));
219  LockWord lock_word = object->GetLockWord();
220  size_t offset = lock_word.ForwardingAddress();
221  DCHECK_LT(offset, image_end_);
222  return offset;
223}
224
225bool ImageWriter::AllocMemory() {
226  size_t length = RoundUp(Runtime::Current()->GetHeap()->GetTotalMemory(), kPageSize);
227  std::string error_msg;
228  image_.reset(MemMap::MapAnonymous("image writer image", NULL, length, PROT_READ | PROT_WRITE,
229                                    &error_msg));
230  if (UNLIKELY(image_.get() == nullptr)) {
231    LOG(ERROR) << "Failed to allocate memory for image file generation: " << error_msg;
232    return false;
233  }
234
235  // Create the image bitmap.
236  image_bitmap_.reset(gc::accounting::SpaceBitmap::Create("image bitmap", image_->Begin(),
237                                                          length));
238  if (image_bitmap_.get() == nullptr) {
239    LOG(ERROR) << "Failed to allocate memory for image bitmap";
240    return false;
241  }
242  return true;
243}
244
245void ImageWriter::ComputeLazyFieldsForImageClasses() {
246  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
247  class_linker->VisitClassesWithoutClassesLock(ComputeLazyFieldsForClassesVisitor, NULL);
248}
249
250bool ImageWriter::ComputeLazyFieldsForClassesVisitor(Class* c, void* /*arg*/) {
251  c->ComputeName();
252  return true;
253}
254
255void ImageWriter::ComputeEagerResolvedStringsCallback(Object* obj, void* arg) {
256  if (!obj->GetClass()->IsStringClass()) {
257    return;
258  }
259  mirror::String* string = obj->AsString();
260  const uint16_t* utf16_string = string->GetCharArray()->GetData() + string->GetOffset();
261  for (DexCache* dex_cache : Runtime::Current()->GetClassLinker()->GetDexCaches()) {
262    const DexFile& dex_file = *dex_cache->GetDexFile();
263    const DexFile::StringId* string_id = dex_file.FindStringId(utf16_string);
264    if (string_id != nullptr) {
265      // This string occurs in this dex file, assign the dex cache entry.
266      uint32_t string_idx = dex_file.GetIndexForStringId(*string_id);
267      if (dex_cache->GetResolvedString(string_idx) == NULL) {
268        dex_cache->SetResolvedString(string_idx, string);
269      }
270    }
271  }
272}
273
274void ImageWriter::ComputeEagerResolvedStrings() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
275  ReaderMutexLock mu(Thread::Current(), *Locks::heap_bitmap_lock_);
276  Runtime::Current()->GetHeap()->VisitObjects(ComputeEagerResolvedStringsCallback, this);
277}
278
279bool ImageWriter::IsImageClass(const Class* klass) {
280  return compiler_driver_.IsImageClass(ClassHelper(klass).GetDescriptor());
281}
282
283struct NonImageClasses {
284  ImageWriter* image_writer;
285  std::set<std::string>* non_image_classes;
286};
287
288void ImageWriter::PruneNonImageClasses() {
289  if (compiler_driver_.GetImageClasses() == NULL) {
290    return;
291  }
292  Runtime* runtime = Runtime::Current();
293  ClassLinker* class_linker = runtime->GetClassLinker();
294
295  // Make a list of classes we would like to prune.
296  std::set<std::string> non_image_classes;
297  NonImageClasses context;
298  context.image_writer = this;
299  context.non_image_classes = &non_image_classes;
300  class_linker->VisitClasses(NonImageClassesVisitor, &context);
301
302  // Remove the undesired classes from the class roots.
303  for (const std::string& it : non_image_classes) {
304    class_linker->RemoveClass(it.c_str(), NULL);
305  }
306
307  // Clear references to removed classes from the DexCaches.
308  ArtMethod* resolution_method = runtime->GetResolutionMethod();
309  for (DexCache* dex_cache : class_linker->GetDexCaches()) {
310    for (size_t i = 0; i < dex_cache->NumResolvedTypes(); i++) {
311      Class* klass = dex_cache->GetResolvedType(i);
312      if (klass != NULL && !IsImageClass(klass)) {
313        dex_cache->SetResolvedType(i, NULL);
314        dex_cache->GetInitializedStaticStorage()->Set(i, NULL);
315      }
316    }
317    for (size_t i = 0; i < dex_cache->NumResolvedMethods(); i++) {
318      ArtMethod* method = dex_cache->GetResolvedMethod(i);
319      if (method != NULL && !IsImageClass(method->GetDeclaringClass())) {
320        dex_cache->SetResolvedMethod(i, resolution_method);
321      }
322    }
323    for (size_t i = 0; i < dex_cache->NumResolvedFields(); i++) {
324      ArtField* field = dex_cache->GetResolvedField(i);
325      if (field != NULL && !IsImageClass(field->GetDeclaringClass())) {
326        dex_cache->SetResolvedField(i, NULL);
327      }
328    }
329  }
330}
331
332bool ImageWriter::NonImageClassesVisitor(Class* klass, void* arg) {
333  NonImageClasses* context = reinterpret_cast<NonImageClasses*>(arg);
334  if (!context->image_writer->IsImageClass(klass)) {
335    context->non_image_classes->insert(ClassHelper(klass).GetDescriptor());
336  }
337  return true;
338}
339
340void ImageWriter::CheckNonImageClassesRemoved()
341    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
342  if (compiler_driver_.GetImageClasses() != nullptr) {
343    gc::Heap* heap = Runtime::Current()->GetHeap();
344    ReaderMutexLock mu(Thread::Current(), *Locks::heap_bitmap_lock_);
345    heap->VisitObjects(CheckNonImageClassesRemovedCallback, this);
346  }
347}
348
349void ImageWriter::CheckNonImageClassesRemovedCallback(Object* obj, void* arg) {
350  ImageWriter* image_writer = reinterpret_cast<ImageWriter*>(arg);
351  if (obj->IsClass()) {
352    Class* klass = obj->AsClass();
353    if (!image_writer->IsImageClass(klass)) {
354      image_writer->DumpImageClasses();
355      CHECK(image_writer->IsImageClass(klass)) << ClassHelper(klass).GetDescriptor()
356                                               << " " << PrettyDescriptor(klass);
357    }
358  }
359}
360
361void ImageWriter::DumpImageClasses() {
362  CompilerDriver::DescriptorSet* image_classes = compiler_driver_.GetImageClasses();
363  CHECK(image_classes != NULL);
364  for (const std::string& image_class : *image_classes) {
365    LOG(INFO) << " " << image_class;
366  }
367}
368
369void ImageWriter::CalculateObjectOffsets(Object* obj) {
370  DCHECK(obj != NULL);
371  // if it is a string, we want to intern it if its not interned.
372  if (obj->GetClass()->IsStringClass()) {
373    // we must be an interned string that was forward referenced and already assigned
374    if (IsImageOffsetAssigned(obj)) {
375      DCHECK_EQ(obj, obj->AsString()->Intern());
376      return;
377    }
378    Thread* self = Thread::Current();
379    SirtRef<Object> sirt_obj(self, obj);
380    mirror::String* interned = obj->AsString()->Intern();
381    if (sirt_obj.get() != interned) {
382      if (!IsImageOffsetAssigned(interned)) {
383        // interned obj is after us, allocate its location early
384        AssignImageOffset(interned);
385      }
386      // point those looking for this object to the interned version.
387      SetImageOffset(sirt_obj.get(), GetImageOffset(interned));
388      return;
389    }
390    // else (obj == interned), nothing to do but fall through to the normal case
391  }
392
393  AssignImageOffset(obj);
394}
395
396ObjectArray<Object>* ImageWriter::CreateImageRoots() const {
397  Runtime* runtime = Runtime::Current();
398  ClassLinker* class_linker = runtime->GetClassLinker();
399  Thread* self = Thread::Current();
400  SirtRef<Class> object_array_class(self, class_linker->FindSystemClass("[Ljava/lang/Object;"));
401
402  // build an Object[] of all the DexCaches used in the source_space_
403  ObjectArray<Object>* dex_caches = ObjectArray<Object>::Alloc(self, object_array_class.get(),
404                                                               class_linker->GetDexCaches().size());
405  int i = 0;
406  for (DexCache* dex_cache : class_linker->GetDexCaches()) {
407    dex_caches->Set(i++, dex_cache);
408  }
409
410  // build an Object[] of the roots needed to restore the runtime
411  SirtRef<ObjectArray<Object> > image_roots(
412      self, ObjectArray<Object>::Alloc(self, object_array_class.get(), ImageHeader::kImageRootsMax));
413  image_roots->Set(ImageHeader::kResolutionMethod, runtime->GetResolutionMethod());
414  image_roots->Set(ImageHeader::kImtConflictMethod, runtime->GetImtConflictMethod());
415  image_roots->Set(ImageHeader::kDefaultImt, runtime->GetDefaultImt());
416  image_roots->Set(ImageHeader::kCalleeSaveMethod,
417                   runtime->GetCalleeSaveMethod(Runtime::kSaveAll));
418  image_roots->Set(ImageHeader::kRefsOnlySaveMethod,
419                   runtime->GetCalleeSaveMethod(Runtime::kRefsOnly));
420  image_roots->Set(ImageHeader::kRefsAndArgsSaveMethod,
421                   runtime->GetCalleeSaveMethod(Runtime::kRefsAndArgs));
422  image_roots->Set(ImageHeader::kOatLocation,
423                   String::AllocFromModifiedUtf8(self, oat_file_->GetLocation().c_str()));
424  image_roots->Set(ImageHeader::kDexCaches, dex_caches);
425  image_roots->Set(ImageHeader::kClassRoots, class_linker->GetClassRoots());
426  for (int i = 0; i < ImageHeader::kImageRootsMax; i++) {
427    CHECK(image_roots->Get(i) != NULL);
428  }
429  return image_roots.get();
430}
431
432// Walk instance fields of the given Class. Separate function to allow recursion on the super
433// class.
434void ImageWriter::WalkInstanceFields(mirror::Object* obj, mirror::Class* klass) {
435  // Visit fields of parent classes first.
436  SirtRef<mirror::Class> sirt_class(Thread::Current(), klass);
437  mirror::Class* super = sirt_class->GetSuperClass();
438  if (super != nullptr) {
439    WalkInstanceFields(obj, super);
440  }
441  //
442  size_t num_reference_fields = sirt_class->NumReferenceInstanceFields();
443  for (size_t i = 0; i < num_reference_fields; ++i) {
444    mirror::ArtField* field = sirt_class->GetInstanceField(i);
445    MemberOffset field_offset = field->GetOffset();
446    mirror::Object* value = obj->GetFieldObject<mirror::Object*>(field_offset, false);
447    if (value != nullptr) {
448      WalkFieldsInOrder(value);
449    }
450  }
451}
452
453// For an unvisited object, visit it then all its children found via fields.
454void ImageWriter::WalkFieldsInOrder(mirror::Object* obj) {
455  if (!IsImageOffsetAssigned(obj)) {
456    // Walk instance fields of all objects
457    Thread* self = Thread::Current();
458    SirtRef<mirror::Object> sirt_obj(self, obj);
459    SirtRef<mirror::Class> klass(self, obj->GetClass());
460    // visit the object itself.
461    CalculateObjectOffsets(sirt_obj.get());
462    WalkInstanceFields(sirt_obj.get(), klass.get());
463    // Walk static fields of a Class.
464    if (sirt_obj->IsClass()) {
465      size_t num_static_fields = klass->NumReferenceStaticFields();
466      for (size_t i = 0; i < num_static_fields; ++i) {
467        mirror::ArtField* field = klass->GetStaticField(i);
468        MemberOffset field_offset = field->GetOffset();
469        mirror::Object* value = sirt_obj->GetFieldObject<mirror::Object*>(field_offset, false);
470        if (value != nullptr) {
471          WalkFieldsInOrder(value);
472        }
473      }
474    } else if (sirt_obj->IsObjectArray()) {
475      // Walk elements of an object array.
476      int32_t length = sirt_obj->AsObjectArray<mirror::Object>()->GetLength();
477      for (int32_t i = 0; i < length; i++) {
478        mirror::ObjectArray<mirror::Object>* obj_array = sirt_obj->AsObjectArray<mirror::Object>();
479        mirror::Object* value = obj_array->Get(i);
480        if (value != nullptr) {
481          WalkFieldsInOrder(value);
482        }
483      }
484    }
485  }
486}
487
488void ImageWriter::WalkFieldsCallback(mirror::Object* obj, void* arg) {
489  ImageWriter* writer = reinterpret_cast<ImageWriter*>(arg);
490  DCHECK(writer != nullptr);
491  writer->WalkFieldsInOrder(obj);
492}
493
494void ImageWriter::CalculateNewObjectOffsets(size_t oat_loaded_size, size_t oat_data_offset) {
495  CHECK_NE(0U, oat_loaded_size);
496  Thread* self = Thread::Current();
497  SirtRef<ObjectArray<Object> > image_roots(self, CreateImageRoots());
498
499  gc::Heap* heap = Runtime::Current()->GetHeap();
500  DCHECK_EQ(0U, image_end_);
501
502  // Leave space for the header, but do not write it yet, we need to
503  // know where image_roots is going to end up
504  image_end_ += RoundUp(sizeof(ImageHeader), 8);  // 64-bit-alignment
505
506  {
507    WriterMutexLock mu(self, *Locks::heap_bitmap_lock_);
508    // TODO: Image spaces only?
509    const char* old = self->StartAssertNoThreadSuspension("ImageWriter");
510    DCHECK_LT(image_end_, image_->Size());
511    // Clear any pre-existing monitors which may have been in the monitor words.
512    heap->VisitObjects(WalkFieldsCallback, this);
513    self->EndAssertNoThreadSuspension(old);
514  }
515
516  const byte* oat_file_begin = image_begin_ + RoundUp(image_end_, kPageSize);
517  const byte* oat_file_end = oat_file_begin + oat_loaded_size;
518  oat_data_begin_ = oat_file_begin + oat_data_offset;
519  const byte* oat_data_end = oat_data_begin_ + oat_file_->Size();
520
521  // Return to write header at start of image with future location of image_roots. At this point,
522  // image_end_ is the size of the image (excluding bitmaps).
523  ImageHeader image_header(reinterpret_cast<uint32_t>(image_begin_),
524                           static_cast<uint32_t>(image_end_),
525                           RoundUp(image_end_, kPageSize),
526                           RoundUp(image_end_ / gc::accounting::SpaceBitmap::kAlignment,
527                                   sizeof(size_t)),
528                           reinterpret_cast<uint32_t>(GetImageAddress(image_roots.get())),
529                           oat_file_->GetOatHeader().GetChecksum(),
530                           reinterpret_cast<uint32_t>(oat_file_begin),
531                           reinterpret_cast<uint32_t>(oat_data_begin_),
532                           reinterpret_cast<uint32_t>(oat_data_end),
533                           reinterpret_cast<uint32_t>(oat_file_end));
534  memcpy(image_->Begin(), &image_header, sizeof(image_header));
535
536  // Note that image_end_ is left at end of used space
537}
538
539void ImageWriter::CopyAndFixupObjects()
540    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
541  Thread* self = Thread::Current();
542  const char* old_cause = self->StartAssertNoThreadSuspension("ImageWriter");
543  gc::Heap* heap = Runtime::Current()->GetHeap();
544  // TODO: heap validation can't handle this fix up pass
545  heap->DisableObjectValidation();
546  // TODO: Image spaces only?
547  WriterMutexLock mu(self, *Locks::heap_bitmap_lock_);
548  heap->VisitObjects(CopyAndFixupObjectsCallback, this);
549  // Fix up the object previously had hash codes.
550  for (const std::pair<mirror::Object*, uint32_t>& hash_pair : saved_hashes_) {
551    hash_pair.first->SetLockWord(LockWord::FromHashCode(hash_pair.second));
552  }
553  saved_hashes_.clear();
554  self->EndAssertNoThreadSuspension(old_cause);
555}
556
557void ImageWriter::CopyAndFixupObjectsCallback(Object* obj, void* arg) {
558  DCHECK(obj != NULL);
559  DCHECK(arg != NULL);
560  ImageWriter* image_writer = reinterpret_cast<ImageWriter*>(arg);
561  // see GetLocalAddress for similar computation
562  size_t offset = image_writer->GetImageOffset(obj);
563  byte* dst = image_writer->image_->Begin() + offset;
564  const byte* src = reinterpret_cast<const byte*>(obj);
565  size_t n = obj->SizeOf();
566  DCHECK_LT(offset + n, image_writer->image_->Size());
567  memcpy(dst, src, n);
568  Object* copy = reinterpret_cast<Object*>(dst);
569  // Write in a hash code of objects which have inflated monitors or a hash code in their monitor
570  // word.
571  copy->SetLockWord(LockWord());
572  image_writer->FixupObject(obj, copy);
573}
574
575void ImageWriter::FixupObject(const Object* orig, Object* copy) {
576  DCHECK(orig != NULL);
577  DCHECK(copy != NULL);
578  copy->SetClass(down_cast<Class*>(GetImageAddress(orig->GetClass())));
579  // TODO: special case init of pointers to malloc data (or removal of these pointers)
580  if (orig->IsClass()) {
581    FixupClass(orig->AsClass(), down_cast<Class*>(copy));
582  } else if (orig->IsObjectArray()) {
583    FixupObjectArray(orig->AsObjectArray<Object>(), down_cast<ObjectArray<Object>*>(copy));
584  } else if (orig->IsArtMethod()) {
585    FixupMethod(orig->AsArtMethod(), down_cast<ArtMethod*>(copy));
586  } else {
587    FixupInstanceFields(orig, copy);
588  }
589}
590
591void ImageWriter::FixupClass(const Class* orig, Class* copy) {
592  FixupInstanceFields(orig, copy);
593  FixupStaticFields(orig, copy);
594}
595
596void ImageWriter::FixupMethod(const ArtMethod* orig, ArtMethod* copy) {
597  FixupInstanceFields(orig, copy);
598
599  // OatWriter replaces the code_ with an offset value. Here we re-adjust to a pointer relative to
600  // oat_begin_
601
602  // The resolution method has a special trampoline to call.
603  if (UNLIKELY(orig == Runtime::Current()->GetResolutionMethod())) {
604#if defined(ART_USE_PORTABLE_COMPILER)
605    copy->SetEntryPointFromCompiledCode(GetOatAddress(portable_resolution_trampoline_offset_));
606#else
607    copy->SetEntryPointFromCompiledCode(GetOatAddress(quick_resolution_trampoline_offset_));
608#endif
609  } else if (UNLIKELY(orig == Runtime::Current()->GetImtConflictMethod())) {
610#if defined(ART_USE_PORTABLE_COMPILER)
611    copy->SetEntryPointFromCompiledCode(GetOatAddress(portable_imt_conflict_trampoline_offset_));
612#else
613    copy->SetEntryPointFromCompiledCode(GetOatAddress(quick_imt_conflict_trampoline_offset_));
614#endif
615  } else {
616    // We assume all methods have code. If they don't currently then we set them to the use the
617    // resolution trampoline. Abstract methods never have code and so we need to make sure their
618    // use results in an AbstractMethodError. We use the interpreter to achieve this.
619    if (UNLIKELY(orig->IsAbstract())) {
620#if defined(ART_USE_PORTABLE_COMPILER)
621      copy->SetEntryPointFromCompiledCode(GetOatAddress(portable_to_interpreter_bridge_offset_));
622#else
623      copy->SetEntryPointFromCompiledCode(GetOatAddress(quick_to_interpreter_bridge_offset_));
624#endif
625      copy->SetEntryPointFromInterpreter(reinterpret_cast<EntryPointFromInterpreter*>
626      (GetOatAddress(interpreter_to_interpreter_bridge_offset_)));
627    } else {
628      copy->SetEntryPointFromInterpreter(reinterpret_cast<EntryPointFromInterpreter*>
629      (GetOatAddress(interpreter_to_compiled_code_bridge_offset_)));
630      // Use original code if it exists. Otherwise, set the code pointer to the resolution
631      // trampoline.
632      const byte* code = GetOatAddress(orig->GetOatCodeOffset());
633      if (code != NULL) {
634        copy->SetEntryPointFromCompiledCode(code);
635      } else {
636#if defined(ART_USE_PORTABLE_COMPILER)
637        copy->SetEntryPointFromCompiledCode(GetOatAddress(portable_resolution_trampoline_offset_));
638#else
639        copy->SetEntryPointFromCompiledCode(GetOatAddress(quick_resolution_trampoline_offset_));
640#endif
641      }
642      if (orig->IsNative()) {
643        // The native method's pointer is set to a stub to lookup via dlsym.
644        // Note this is not the code_ pointer, that is handled above.
645        copy->SetNativeMethod(GetOatAddress(jni_dlsym_lookup_offset_));
646      } else {
647        // Normal (non-abstract non-native) methods have various tables to relocate.
648        uint32_t mapping_table_off = orig->GetOatMappingTableOffset();
649        const byte* mapping_table = GetOatAddress(mapping_table_off);
650        copy->SetMappingTable(mapping_table);
651
652        uint32_t vmap_table_offset = orig->GetOatVmapTableOffset();
653        const byte* vmap_table = GetOatAddress(vmap_table_offset);
654        copy->SetVmapTable(vmap_table);
655
656        uint32_t native_gc_map_offset = orig->GetOatNativeGcMapOffset();
657        const byte* native_gc_map = GetOatAddress(native_gc_map_offset);
658        copy->SetNativeGcMap(reinterpret_cast<const uint8_t*>(native_gc_map));
659      }
660    }
661  }
662}
663
664void ImageWriter::FixupObjectArray(const ObjectArray<Object>* orig, ObjectArray<Object>* copy) {
665  for (int32_t i = 0; i < orig->GetLength(); ++i) {
666    const Object* element = orig->Get(i);
667    copy->SetPtrWithoutChecks(i, GetImageAddress(element));
668  }
669}
670
671void ImageWriter::FixupInstanceFields(const Object* orig, Object* copy) {
672  DCHECK(orig != NULL);
673  DCHECK(copy != NULL);
674  Class* klass = orig->GetClass();
675  DCHECK(klass != NULL);
676  FixupFields(orig, copy, klass->GetReferenceInstanceOffsets(), false);
677}
678
679void ImageWriter::FixupStaticFields(const Class* orig, Class* copy) {
680  DCHECK(orig != NULL);
681  DCHECK(copy != NULL);
682  FixupFields(orig, copy, orig->GetReferenceStaticOffsets(), true);
683}
684
685void ImageWriter::FixupFields(const Object* orig,
686                              Object* copy,
687                              uint32_t ref_offsets,
688                              bool is_static) {
689  if (ref_offsets != CLASS_WALK_SUPER) {
690    // Found a reference offset bitmap.  Fixup the specified offsets.
691    while (ref_offsets != 0) {
692      size_t right_shift = CLZ(ref_offsets);
693      MemberOffset byte_offset = CLASS_OFFSET_FROM_CLZ(right_shift);
694      const Object* ref = orig->GetFieldObject<const Object*>(byte_offset, false);
695      // Use SetFieldPtr to avoid card marking since we are writing to the image.
696      copy->SetFieldPtr(byte_offset, GetImageAddress(ref), false);
697      ref_offsets &= ~(CLASS_HIGH_BIT >> right_shift);
698    }
699  } else {
700    // There is no reference offset bitmap.  In the non-static case,
701    // walk up the class inheritance hierarchy and find reference
702    // offsets the hard way. In the static case, just consider this
703    // class.
704    for (const Class *klass = is_static ? orig->AsClass() : orig->GetClass();
705         klass != NULL;
706         klass = is_static ? NULL : klass->GetSuperClass()) {
707      size_t num_reference_fields = (is_static
708                                     ? klass->NumReferenceStaticFields()
709                                     : klass->NumReferenceInstanceFields());
710      for (size_t i = 0; i < num_reference_fields; ++i) {
711        ArtField* field = (is_static
712                           ? klass->GetStaticField(i)
713                           : klass->GetInstanceField(i));
714        MemberOffset field_offset = field->GetOffset();
715        const Object* ref = orig->GetFieldObject<const Object*>(field_offset, false);
716        // Use SetFieldPtr to avoid card marking since we are writing to the image.
717        copy->SetFieldPtr(field_offset, GetImageAddress(ref), false);
718      }
719    }
720  }
721  if (!is_static && orig->IsReferenceInstance()) {
722    // Fix-up referent, that isn't marked as an object field, for References.
723    ArtField* field = orig->GetClass()->FindInstanceField("referent", "Ljava/lang/Object;");
724    MemberOffset field_offset = field->GetOffset();
725    const Object* ref = orig->GetFieldObject<const Object*>(field_offset, false);
726    // Use SetFieldPtr to avoid card marking since we are writing to the image.
727    copy->SetFieldPtr(field_offset, GetImageAddress(ref), false);
728  }
729}
730
731static ArtMethod* GetTargetMethod(const CompilerDriver::PatchInformation* patch)
732    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
733  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
734  Thread* self = Thread::Current();
735  SirtRef<mirror::DexCache> dex_cache(self, class_linker->FindDexCache(patch->GetDexFile()));
736  SirtRef<mirror::ClassLoader> class_loader(self, nullptr);
737  ArtMethod* method = class_linker->ResolveMethod(patch->GetDexFile(),
738                                                  patch->GetTargetMethodIdx(),
739                                                  dex_cache,
740                                                  class_loader,
741                                                  NULL,
742                                                  patch->GetTargetInvokeType());
743  CHECK(method != NULL)
744    << patch->GetDexFile().GetLocation() << " " << patch->GetTargetMethodIdx();
745  CHECK(!method->IsRuntimeMethod())
746    << patch->GetDexFile().GetLocation() << " " << patch->GetTargetMethodIdx();
747  CHECK(dex_cache->GetResolvedMethods()->Get(patch->GetTargetMethodIdx()) == method)
748    << patch->GetDexFile().GetLocation() << " " << patch->GetReferrerMethodIdx() << " "
749    << PrettyMethod(dex_cache->GetResolvedMethods()->Get(patch->GetTargetMethodIdx())) << " "
750    << PrettyMethod(method);
751  return method;
752}
753
754void ImageWriter::PatchOatCodeAndMethods() {
755  Thread* self = Thread::Current();
756  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
757  const char* old_cause = self->StartAssertNoThreadSuspension("ImageWriter");
758
759  typedef std::vector<const CompilerDriver::PatchInformation*> Patches;
760  const Patches& code_to_patch = compiler_driver_.GetCodeToPatch();
761  for (size_t i = 0; i < code_to_patch.size(); i++) {
762    const CompilerDriver::PatchInformation* patch = code_to_patch[i];
763    ArtMethod* target = GetTargetMethod(patch);
764    uint32_t code = reinterpret_cast<uint32_t>(class_linker->GetOatCodeFor(target));
765    uint32_t code_base = reinterpret_cast<uint32_t>(&oat_file_->GetOatHeader());
766    uint32_t code_offset = code - code_base;
767    SetPatchLocation(patch, reinterpret_cast<uint32_t>(GetOatAddress(code_offset)));
768  }
769
770  const Patches& methods_to_patch = compiler_driver_.GetMethodsToPatch();
771  for (size_t i = 0; i < methods_to_patch.size(); i++) {
772    const CompilerDriver::PatchInformation* patch = methods_to_patch[i];
773    ArtMethod* target = GetTargetMethod(patch);
774    SetPatchLocation(patch, reinterpret_cast<uint32_t>(GetImageAddress(target)));
775  }
776
777  // Update the image header with the new checksum after patching
778  ImageHeader* image_header = reinterpret_cast<ImageHeader*>(image_->Begin());
779  image_header->SetOatChecksum(oat_file_->GetOatHeader().GetChecksum());
780  self->EndAssertNoThreadSuspension(old_cause);
781}
782
783void ImageWriter::SetPatchLocation(const CompilerDriver::PatchInformation* patch, uint32_t value) {
784  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
785  const void* oat_code = class_linker->GetOatCodeFor(patch->GetDexFile(),
786                                                     patch->GetReferrerClassDefIdx(),
787                                                     patch->GetReferrerMethodIdx());
788  OatHeader& oat_header = const_cast<OatHeader&>(oat_file_->GetOatHeader());
789  // TODO: make this Thumb2 specific
790  uint8_t* base = reinterpret_cast<uint8_t*>(reinterpret_cast<uint32_t>(oat_code) & ~0x1);
791  uint32_t* patch_location = reinterpret_cast<uint32_t*>(base + patch->GetLiteralOffset());
792  if (kIsDebugBuild) {
793    const DexFile::MethodId& id = patch->GetDexFile().GetMethodId(patch->GetTargetMethodIdx());
794    uint32_t expected = reinterpret_cast<uint32_t>(&id);
795    uint32_t actual = *patch_location;
796    CHECK(actual == expected || actual == value) << std::hex
797      << "actual=" << actual
798      << "expected=" << expected
799      << "value=" << value;
800  }
801  *patch_location = value;
802  oat_header.UpdateChecksum(patch_location, sizeof(value));
803}
804
805}  // namespace art
806