image_writer.cc revision dfb325e0ddd746cd8f7c2e3723b3a573eb7cc111 
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 "mirror/art_field-inl.h"
40#include "mirror/art_method-inl.h"
41#include "mirror/array-inl.h"
42#include "mirror/class-inl.h"
43#include "mirror/class_loader.h"
44#include "mirror/dex_cache-inl.h"
45#include "mirror/object-inl.h"
46#include "mirror/object_array-inl.h"
47#include "oat.h"
48#include "oat_file.h"
49#include "object_utils.h"
50#include "runtime.h"
51#include "scoped_thread_state_change.h"
52#include "sirt_ref.h"
53#include "UniquePtr.h"
54#include "utils.h"
55
56using ::art::mirror::ArtField;
57using ::art::mirror::ArtMethod;
58using ::art::mirror::Class;
59using ::art::mirror::DexCache;
60using ::art::mirror::EntryPointFromInterpreter;
61using ::art::mirror::Object;
62using ::art::mirror::ObjectArray;
63using ::art::mirror::String;
64
65namespace art {
66
67bool ImageWriter::Write(const std::string& image_filename,
68                        uintptr_t image_begin,
69                        const std::string& oat_filename,
70                        const std::string& oat_location) {
71  CHECK(!image_filename.empty());
72
73  CHECK_NE(image_begin, 0U);
74  image_begin_ = reinterpret_cast<byte*>(image_begin);
75
76  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
77  const std::vector<DexCache*>& all_dex_caches = class_linker->GetDexCaches();
78  dex_caches_.insert(all_dex_caches.begin(), all_dex_caches.end());
79
80  UniquePtr<File> oat_file(OS::OpenFileReadWrite(oat_filename.c_str()));
81  if (oat_file.get() == NULL) {
82    LOG(ERROR) << "Failed to open oat file " << oat_filename << " for " << oat_location;
83    return false;
84  }
85  std::string error_msg;
86  oat_file_ = OatFile::OpenWritable(oat_file.get(), oat_location, &error_msg);
87  if (oat_file_ == nullptr) {
88    LOG(ERROR) << "Failed to open writable oat file " << oat_filename << " for " << oat_location
89        << ": " << error_msg;
90    return false;
91  }
92  CHECK_EQ(class_linker->RegisterOatFile(oat_file_), oat_file_);
93
94  interpreter_to_interpreter_bridge_offset_ =
95      oat_file_->GetOatHeader().GetInterpreterToInterpreterBridgeOffset();
96  interpreter_to_compiled_code_bridge_offset_ =
97      oat_file_->GetOatHeader().GetInterpreterToCompiledCodeBridgeOffset();
98
99  jni_dlsym_lookup_offset_ = oat_file_->GetOatHeader().GetJniDlsymLookupOffset();
100
101  portable_resolution_trampoline_offset_ =
102      oat_file_->GetOatHeader().GetPortableResolutionTrampolineOffset();
103  portable_to_interpreter_bridge_offset_ =
104      oat_file_->GetOatHeader().GetPortableToInterpreterBridgeOffset();
105
106  quick_resolution_trampoline_offset_ =
107      oat_file_->GetOatHeader().GetQuickResolutionTrampolineOffset();
108  quick_to_interpreter_bridge_offset_ =
109      oat_file_->GetOatHeader().GetQuickToInterpreterBridgeOffset();
110  {
111    Thread::Current()->TransitionFromSuspendedToRunnable();
112    PruneNonImageClasses();  // Remove junk
113    ComputeLazyFieldsForImageClasses();  // Add useful information
114    ComputeEagerResolvedStrings();
115    Thread::Current()->TransitionFromRunnableToSuspended(kNative);
116  }
117  gc::Heap* heap = Runtime::Current()->GetHeap();
118  heap->CollectGarbage(false);  // Remove garbage.
119  // Trim size of alloc spaces.
120  for (const auto& space : heap->GetContinuousSpaces()) {
121    if (space->IsDlMallocSpace()) {
122      space->AsDlMallocSpace()->Trim();
123    }
124  }
125
126  if (!AllocMemory()) {
127    return false;
128  }
129#ifndef NDEBUG
130  {  // NOLINT(whitespace/braces)
131    ScopedObjectAccess soa(Thread::Current());
132    CheckNonImageClassesRemoved();
133  }
134#endif
135  Thread::Current()->TransitionFromSuspendedToRunnable();
136  size_t oat_loaded_size = 0;
137  size_t oat_data_offset = 0;
138  ElfWriter::GetOatElfInformation(oat_file.get(), oat_loaded_size, oat_data_offset);
139  CalculateNewObjectOffsets(oat_loaded_size, oat_data_offset);
140  CopyAndFixupObjects();
141  PatchOatCodeAndMethods();
142  // Record allocations into the image bitmap.
143  RecordImageAllocations();
144  Thread::Current()->TransitionFromRunnableToSuspended(kNative);
145
146  UniquePtr<File> image_file(OS::CreateEmptyFile(image_filename.c_str()));
147  ImageHeader* image_header = reinterpret_cast<ImageHeader*>(image_->Begin());
148  if (image_file.get() == NULL) {
149    LOG(ERROR) << "Failed to open image file " << image_filename;
150    return false;
151  }
152  if (fchmod(image_file->Fd(), 0644) != 0) {
153    PLOG(ERROR) << "Failed to make image file world readable: " << image_filename;
154    return EXIT_FAILURE;
155  }
156
157  // Write out the image.
158  CHECK_EQ(image_end_, image_header->GetImageSize());
159  if (!image_file->WriteFully(image_->Begin(), image_end_)) {
160    PLOG(ERROR) << "Failed to write image file " << image_filename;
161    return false;
162  }
163
164  // Write out the image bitmap at the page aligned start of the image end.
165  CHECK_ALIGNED(image_header->GetImageBitmapOffset(), kPageSize);
166  if (!image_file->Write(reinterpret_cast<char*>(image_bitmap_->Begin()),
167                         image_header->GetImageBitmapSize(),
168                         image_header->GetImageBitmapOffset())) {
169    PLOG(ERROR) << "Failed to write image file " << image_filename;
170    return false;
171  }
172
173  return true;
174}
175
176void ImageWriter::RecordImageAllocations() {
177  uint64_t start_time = NanoTime();
178  CHECK(image_bitmap_.get() != nullptr);
179  for (const auto& it : offsets_) {
180    mirror::Object* obj = reinterpret_cast<mirror::Object*>(image_->Begin() + it.second);
181    DCHECK_ALIGNED(obj, kObjectAlignment);
182    image_bitmap_->Set(obj);
183  }
184  LOG(INFO) << "RecordImageAllocations took " << PrettyDuration(NanoTime() - start_time);
185}
186
187bool ImageWriter::AllocMemory() {
188  size_t size = 0;
189  for (const auto& space : Runtime::Current()->GetHeap()->GetContinuousSpaces()) {
190    if (space->IsDlMallocSpace()) {
191      size += space->Size();
192    }
193  }
194
195  int prot = PROT_READ | PROT_WRITE;
196  size_t length = RoundUp(size, kPageSize);
197  std::string error_msg;
198  image_.reset(MemMap::MapAnonymous("image writer image", NULL, length, prot, &error_msg));
199  if (UNLIKELY(image_.get() == nullptr)) {
200    LOG(ERROR) << "Failed to allocate memory for image file generation: " << error_msg;
201    return false;
202  }
203  return true;
204}
205
206void ImageWriter::ComputeLazyFieldsForImageClasses() {
207  Runtime* runtime = Runtime::Current();
208  ClassLinker* class_linker = runtime->GetClassLinker();
209  class_linker->VisitClassesWithoutClassesLock(ComputeLazyFieldsForClassesVisitor, NULL);
210}
211
212bool ImageWriter::ComputeLazyFieldsForClassesVisitor(Class* c, void* /*arg*/) {
213  c->ComputeName();
214  return true;
215}
216
217void ImageWriter::ComputeEagerResolvedStringsCallback(Object* obj, void* arg) {
218  if (!obj->GetClass()->IsStringClass()) {
219    return;
220  }
221  String* string = obj->AsString();
222  const uint16_t* utf16_string = string->GetCharArray()->GetData() + string->GetOffset();
223  ImageWriter* writer = reinterpret_cast<ImageWriter*>(arg);
224  for (DexCache* dex_cache : writer->dex_caches_) {
225    const DexFile& dex_file = *dex_cache->GetDexFile();
226    const DexFile::StringId* string_id = dex_file.FindStringId(utf16_string);
227    if (string_id != NULL) {
228      // This string occurs in this dex file, assign the dex cache entry.
229      uint32_t string_idx = dex_file.GetIndexForStringId(*string_id);
230      if (dex_cache->GetResolvedString(string_idx) == NULL) {
231        dex_cache->SetResolvedString(string_idx, string);
232      }
233    }
234  }
235}
236
237void ImageWriter::ComputeEagerResolvedStrings()
238    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
239  // TODO: Check image spaces only?
240  gc::Heap* heap = Runtime::Current()->GetHeap();
241  WriterMutexLock mu(Thread::Current(), *Locks::heap_bitmap_lock_);
242  heap->FlushAllocStack();
243  heap->GetLiveBitmap()->Walk(ComputeEagerResolvedStringsCallback, this);
244}
245
246bool ImageWriter::IsImageClass(const Class* klass) {
247  return compiler_driver_.IsImageClass(ClassHelper(klass).GetDescriptor());
248}
249
250struct NonImageClasses {
251  ImageWriter* image_writer;
252  std::set<std::string>* non_image_classes;
253};
254
255void ImageWriter::PruneNonImageClasses() {
256  if (compiler_driver_.GetImageClasses() == NULL) {
257    return;
258  }
259  Runtime* runtime = Runtime::Current();
260  ClassLinker* class_linker = runtime->GetClassLinker();
261
262  // Make a list of classes we would like to prune.
263  std::set<std::string> non_image_classes;
264  NonImageClasses context;
265  context.image_writer = this;
266  context.non_image_classes = &non_image_classes;
267  class_linker->VisitClasses(NonImageClassesVisitor, &context);
268
269  // Remove the undesired classes from the class roots.
270  for (const std::string& it : non_image_classes) {
271    class_linker->RemoveClass(it.c_str(), NULL);
272  }
273
274  // Clear references to removed classes from the DexCaches.
275  ArtMethod* resolution_method = runtime->GetResolutionMethod();
276  for (DexCache* dex_cache : dex_caches_) {
277    for (size_t i = 0; i < dex_cache->NumResolvedTypes(); i++) {
278      Class* klass = dex_cache->GetResolvedType(i);
279      if (klass != NULL && !IsImageClass(klass)) {
280        dex_cache->SetResolvedType(i, NULL);
281        dex_cache->GetInitializedStaticStorage()->Set(i, NULL);
282      }
283    }
284    for (size_t i = 0; i < dex_cache->NumResolvedMethods(); i++) {
285      ArtMethod* method = dex_cache->GetResolvedMethod(i);
286      if (method != NULL && !IsImageClass(method->GetDeclaringClass())) {
287        dex_cache->SetResolvedMethod(i, resolution_method);
288      }
289    }
290    for (size_t i = 0; i < dex_cache->NumResolvedFields(); i++) {
291      ArtField* field = dex_cache->GetResolvedField(i);
292      if (field != NULL && !IsImageClass(field->GetDeclaringClass())) {
293        dex_cache->SetResolvedField(i, NULL);
294      }
295    }
296  }
297}
298
299bool ImageWriter::NonImageClassesVisitor(Class* klass, void* arg) {
300  NonImageClasses* context = reinterpret_cast<NonImageClasses*>(arg);
301  if (!context->image_writer->IsImageClass(klass)) {
302    context->non_image_classes->insert(ClassHelper(klass).GetDescriptor());
303  }
304  return true;
305}
306
307void ImageWriter::CheckNonImageClassesRemoved()
308    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
309  if (compiler_driver_.GetImageClasses() == NULL) {
310    return;
311  }
312
313  gc::Heap* heap = Runtime::Current()->GetHeap();
314  Thread* self = Thread::Current();
315  {
316    WriterMutexLock mu(self, *Locks::heap_bitmap_lock_);
317    heap->FlushAllocStack();
318  }
319
320  ReaderMutexLock mu(self, *Locks::heap_bitmap_lock_);
321  heap->GetLiveBitmap()->Walk(CheckNonImageClassesRemovedCallback, this);
322}
323
324void ImageWriter::CheckNonImageClassesRemovedCallback(Object* obj, void* arg) {
325  ImageWriter* image_writer = reinterpret_cast<ImageWriter*>(arg);
326  if (!obj->IsClass()) {
327    return;
328  }
329  Class* klass = obj->AsClass();
330  if (!image_writer->IsImageClass(klass)) {
331    image_writer->DumpImageClasses();
332    CHECK(image_writer->IsImageClass(klass)) << ClassHelper(klass).GetDescriptor()
333                                             << " " << PrettyDescriptor(klass);
334  }
335}
336
337void ImageWriter::DumpImageClasses() {
338  CompilerDriver::DescriptorSet* image_classes = compiler_driver_.GetImageClasses();
339  CHECK(image_classes != NULL);
340  for (const std::string& image_class : *image_classes) {
341    LOG(INFO) << " " << image_class;
342  }
343}
344
345void ImageWriter::CalculateNewObjectOffsetsCallback(Object* obj, void* arg) {
346  DCHECK(obj != NULL);
347  DCHECK(arg != NULL);
348  ImageWriter* image_writer = reinterpret_cast<ImageWriter*>(arg);
349
350  // if it is a string, we want to intern it if its not interned.
351  if (obj->GetClass()->IsStringClass()) {
352    // we must be an interned string that was forward referenced and already assigned
353    if (image_writer->IsImageOffsetAssigned(obj)) {
354      DCHECK_EQ(obj, obj->AsString()->Intern());
355      return;
356    }
357    SirtRef<String> interned(Thread::Current(), obj->AsString()->Intern());
358    if (obj != interned.get()) {
359      if (!image_writer->IsImageOffsetAssigned(interned.get())) {
360        // interned obj is after us, allocate its location early
361        image_writer->AssignImageOffset(interned.get());
362      }
363      // point those looking for this object to the interned version.
364      image_writer->SetImageOffset(obj, image_writer->GetImageOffset(interned.get()));
365      return;
366    }
367    // else (obj == interned), nothing to do but fall through to the normal case
368  }
369
370  image_writer->AssignImageOffset(obj);
371}
372
373ObjectArray<Object>* ImageWriter::CreateImageRoots() const {
374  Runtime* runtime = Runtime::Current();
375  ClassLinker* class_linker = runtime->GetClassLinker();
376  Class* object_array_class = class_linker->FindSystemClass("[Ljava/lang/Object;");
377  Thread* self = Thread::Current();
378
379  // build an Object[] of all the DexCaches used in the source_space_
380  ObjectArray<Object>* dex_caches = ObjectArray<Object>::Alloc(self, object_array_class,
381                                                               dex_caches_.size());
382  int i = 0;
383  for (DexCache* dex_cache : dex_caches_) {
384    dex_caches->Set(i++, dex_cache);
385  }
386
387  // build an Object[] of the roots needed to restore the runtime
388  SirtRef<ObjectArray<Object> >
389      image_roots(self,
390                  ObjectArray<Object>::Alloc(self, object_array_class,
391                                             ImageHeader::kImageRootsMax));
392  image_roots->Set(ImageHeader::kResolutionMethod, runtime->GetResolutionMethod());
393  image_roots->Set(ImageHeader::kCalleeSaveMethod,
394                   runtime->GetCalleeSaveMethod(Runtime::kSaveAll));
395  image_roots->Set(ImageHeader::kRefsOnlySaveMethod,
396                   runtime->GetCalleeSaveMethod(Runtime::kRefsOnly));
397  image_roots->Set(ImageHeader::kRefsAndArgsSaveMethod,
398                   runtime->GetCalleeSaveMethod(Runtime::kRefsAndArgs));
399  image_roots->Set(ImageHeader::kOatLocation,
400                   String::AllocFromModifiedUtf8(self, oat_file_->GetLocation().c_str()));
401  image_roots->Set(ImageHeader::kDexCaches,
402                   dex_caches);
403  image_roots->Set(ImageHeader::kClassRoots,
404                   class_linker->GetClassRoots());
405  for (int i = 0; i < ImageHeader::kImageRootsMax; i++) {
406    CHECK(image_roots->Get(i) != NULL);
407  }
408  return image_roots.get();
409}
410
411void ImageWriter::CalculateNewObjectOffsets(size_t oat_loaded_size, size_t oat_data_offset) {
412  CHECK_NE(0U, oat_loaded_size);
413  Thread* self = Thread::Current();
414  SirtRef<ObjectArray<Object> > image_roots(self, CreateImageRoots());
415
416  gc::Heap* heap = Runtime::Current()->GetHeap();
417  const auto& spaces = heap->GetContinuousSpaces();
418  DCHECK(!spaces.empty());
419  DCHECK_EQ(0U, image_end_);
420
421  // Leave space for the header, but do not write it yet, we need to
422  // know where image_roots is going to end up
423  image_end_ += RoundUp(sizeof(ImageHeader), 8);  // 64-bit-alignment
424
425  {
426    WriterMutexLock mu(self, *Locks::heap_bitmap_lock_);
427    heap->FlushAllocStack();
428    // TODO: Image spaces only?
429    // TODO: Add InOrderWalk to heap bitmap.
430    const char* old = self->StartAssertNoThreadSuspension("ImageWriter");
431    DCHECK(heap->GetLargeObjectsSpace()->GetLiveObjects()->IsEmpty());
432    for (const auto& space : spaces) {
433      space->GetLiveBitmap()->InOrderWalk(CalculateNewObjectOffsetsCallback, this);
434      DCHECK_LT(image_end_, image_->Size());
435    }
436    self->EndAssertNoThreadSuspension(old);
437  }
438
439  // Create the image bitmap.
440  image_bitmap_.reset(gc::accounting::SpaceBitmap::Create("image bitmap", image_->Begin(),
441                                                          image_end_));
442  const byte* oat_file_begin = image_begin_ + RoundUp(image_end_, kPageSize);
443  const byte* oat_file_end = oat_file_begin + oat_loaded_size;
444  oat_data_begin_ = oat_file_begin + oat_data_offset;
445  const byte* oat_data_end = oat_data_begin_ + oat_file_->Size();
446
447  // Return to write header at start of image with future location of image_roots. At this point,
448  // image_end_ is the size of the image (excluding bitmaps).
449  ImageHeader image_header(reinterpret_cast<uint32_t>(image_begin_),
450                           static_cast<uint32_t>(image_end_),
451                           RoundUp(image_end_, kPageSize),
452                           image_bitmap_->Size(),
453                           reinterpret_cast<uint32_t>(GetImageAddress(image_roots.get())),
454                           oat_file_->GetOatHeader().GetChecksum(),
455                           reinterpret_cast<uint32_t>(oat_file_begin),
456                           reinterpret_cast<uint32_t>(oat_data_begin_),
457                           reinterpret_cast<uint32_t>(oat_data_end),
458                           reinterpret_cast<uint32_t>(oat_file_end));
459  memcpy(image_->Begin(), &image_header, sizeof(image_header));
460
461  // Note that image_end_ is left at end of used space
462}
463
464void ImageWriter::CopyAndFixupObjects()
465    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
466  Thread* self = Thread::Current();
467  const char* old_cause = self->StartAssertNoThreadSuspension("ImageWriter");
468  gc::Heap* heap = Runtime::Current()->GetHeap();
469  // TODO: heap validation can't handle this fix up pass
470  heap->DisableObjectValidation();
471  // TODO: Image spaces only?
472  WriterMutexLock mu(self, *Locks::heap_bitmap_lock_);
473  heap->FlushAllocStack();
474  heap->GetLiveBitmap()->Walk(CopyAndFixupObjectsCallback, this);
475  self->EndAssertNoThreadSuspension(old_cause);
476}
477
478void ImageWriter::CopyAndFixupObjectsCallback(Object* object, void* arg) {
479  DCHECK(object != NULL);
480  DCHECK(arg != NULL);
481  const Object* obj = object;
482  ImageWriter* image_writer = reinterpret_cast<ImageWriter*>(arg);
483
484  // see GetLocalAddress for similar computation
485  size_t offset = image_writer->GetImageOffset(obj);
486  byte* dst = image_writer->image_->Begin() + offset;
487  const byte* src = reinterpret_cast<const byte*>(obj);
488  size_t n = obj->SizeOf();
489  DCHECK_LT(offset + n, image_writer->image_->Size());
490  memcpy(dst, src, n);
491  Object* copy = reinterpret_cast<Object*>(dst);
492  copy->SetField32(Object::MonitorOffset(), 0, false);  // We may have inflated the lock during compilation.
493  image_writer->FixupObject(obj, copy);
494}
495
496void ImageWriter::FixupObject(const Object* orig, Object* copy) {
497  DCHECK(orig != NULL);
498  DCHECK(copy != NULL);
499  copy->SetClass(down_cast<Class*>(GetImageAddress(orig->GetClass())));
500  // TODO: special case init of pointers to malloc data (or removal of these pointers)
501  if (orig->IsClass()) {
502    FixupClass(orig->AsClass(), down_cast<Class*>(copy));
503  } else if (orig->IsObjectArray()) {
504    FixupObjectArray(orig->AsObjectArray<Object>(), down_cast<ObjectArray<Object>*>(copy));
505  } else if (orig->IsArtMethod()) {
506    FixupMethod(orig->AsArtMethod(), down_cast<ArtMethod*>(copy));
507  } else {
508    FixupInstanceFields(orig, copy);
509  }
510}
511
512void ImageWriter::FixupClass(const Class* orig, Class* copy) {
513  FixupInstanceFields(orig, copy);
514  FixupStaticFields(orig, copy);
515}
516
517void ImageWriter::FixupMethod(const ArtMethod* orig, ArtMethod* copy) {
518  FixupInstanceFields(orig, copy);
519
520  // OatWriter replaces the code_ with an offset value. Here we re-adjust to a pointer relative to
521  // oat_begin_
522
523  // The resolution method has a special trampoline to call.
524  if (UNLIKELY(orig == Runtime::Current()->GetResolutionMethod())) {
525#if defined(ART_USE_PORTABLE_COMPILER)
526    copy->SetEntryPointFromCompiledCode(GetOatAddress(portable_resolution_trampoline_offset_));
527#else
528    copy->SetEntryPointFromCompiledCode(GetOatAddress(quick_resolution_trampoline_offset_));
529#endif
530  } else {
531    // We assume all methods have code. If they don't currently then we set them to the use the
532    // resolution trampoline. Abstract methods never have code and so we need to make sure their
533    // use results in an AbstractMethodError. We use the interpreter to achieve this.
534    if (UNLIKELY(orig->IsAbstract())) {
535#if defined(ART_USE_PORTABLE_COMPILER)
536      copy->SetEntryPointFromCompiledCode(GetOatAddress(portable_to_interpreter_bridge_offset_));
537#else
538      copy->SetEntryPointFromCompiledCode(GetOatAddress(quick_to_interpreter_bridge_offset_));
539#endif
540      copy->SetEntryPointFromInterpreter(reinterpret_cast<EntryPointFromInterpreter*>
541      (GetOatAddress(interpreter_to_interpreter_bridge_offset_)));
542    } else {
543      copy->SetEntryPointFromInterpreter(reinterpret_cast<EntryPointFromInterpreter*>
544      (GetOatAddress(interpreter_to_compiled_code_bridge_offset_)));
545      // Use original code if it exists. Otherwise, set the code pointer to the resolution
546      // trampoline.
547      const byte* code = GetOatAddress(orig->GetOatCodeOffset());
548      if (code != NULL) {
549        copy->SetEntryPointFromCompiledCode(code);
550      } else {
551#if defined(ART_USE_PORTABLE_COMPILER)
552        copy->SetEntryPointFromCompiledCode(GetOatAddress(portable_resolution_trampoline_offset_));
553#else
554        copy->SetEntryPointFromCompiledCode(GetOatAddress(quick_resolution_trampoline_offset_));
555#endif
556      }
557      if (orig->IsNative()) {
558        // The native method's pointer is set to a stub to lookup via dlsym.
559        // Note this is not the code_ pointer, that is handled above.
560        copy->SetNativeMethod(GetOatAddress(jni_dlsym_lookup_offset_));
561      } else {
562        // Normal (non-abstract non-native) methods have various tables to relocate.
563        uint32_t mapping_table_off = orig->GetOatMappingTableOffset();
564        const byte* mapping_table = GetOatAddress(mapping_table_off);
565        copy->SetMappingTable(mapping_table);
566
567        uint32_t vmap_table_offset = orig->GetOatVmapTableOffset();
568        const byte* vmap_table = GetOatAddress(vmap_table_offset);
569        copy->SetVmapTable(vmap_table);
570
571        uint32_t native_gc_map_offset = orig->GetOatNativeGcMapOffset();
572        const byte* native_gc_map = GetOatAddress(native_gc_map_offset);
573        copy->SetNativeGcMap(reinterpret_cast<const uint8_t*>(native_gc_map));
574      }
575    }
576  }
577}
578
579void ImageWriter::FixupObjectArray(const ObjectArray<Object>* orig, ObjectArray<Object>* copy) {
580  for (int32_t i = 0; i < orig->GetLength(); ++i) {
581    const Object* element = orig->Get(i);
582    copy->SetPtrWithoutChecks(i, GetImageAddress(element));
583  }
584}
585
586void ImageWriter::FixupInstanceFields(const Object* orig, Object* copy) {
587  DCHECK(orig != NULL);
588  DCHECK(copy != NULL);
589  Class* klass = orig->GetClass();
590  DCHECK(klass != NULL);
591  FixupFields(orig,
592              copy,
593              klass->GetReferenceInstanceOffsets(),
594              false);
595}
596
597void ImageWriter::FixupStaticFields(const Class* orig, Class* copy) {
598  DCHECK(orig != NULL);
599  DCHECK(copy != NULL);
600  FixupFields(orig,
601              copy,
602              orig->GetReferenceStaticOffsets(),
603              true);
604}
605
606void ImageWriter::FixupFields(const Object* orig,
607                              Object* copy,
608                              uint32_t ref_offsets,
609                              bool is_static) {
610  if (ref_offsets != CLASS_WALK_SUPER) {
611    // Found a reference offset bitmap.  Fixup the specified offsets.
612    while (ref_offsets != 0) {
613      size_t right_shift = CLZ(ref_offsets);
614      MemberOffset byte_offset = CLASS_OFFSET_FROM_CLZ(right_shift);
615      const Object* ref = orig->GetFieldObject<const Object*>(byte_offset, false);
616      // Use SetFieldPtr to avoid card marking since we are writing to the image.
617      copy->SetFieldPtr(byte_offset, GetImageAddress(ref), false);
618      ref_offsets &= ~(CLASS_HIGH_BIT >> right_shift);
619    }
620  } else {
621    // There is no reference offset bitmap.  In the non-static case,
622    // walk up the class inheritance hierarchy and find reference
623    // offsets the hard way. In the static case, just consider this
624    // class.
625    for (const Class *klass = is_static ? orig->AsClass() : orig->GetClass();
626         klass != NULL;
627         klass = is_static ? NULL : klass->GetSuperClass()) {
628      size_t num_reference_fields = (is_static
629                                     ? klass->NumReferenceStaticFields()
630                                     : klass->NumReferenceInstanceFields());
631      for (size_t i = 0; i < num_reference_fields; ++i) {
632        ArtField* field = (is_static
633                           ? klass->GetStaticField(i)
634                           : klass->GetInstanceField(i));
635        MemberOffset field_offset = field->GetOffset();
636        const Object* ref = orig->GetFieldObject<const Object*>(field_offset, false);
637        // Use SetFieldPtr to avoid card marking since we are writing to the image.
638        copy->SetFieldPtr(field_offset, GetImageAddress(ref), false);
639      }
640    }
641  }
642  if (!is_static && orig->IsReferenceInstance()) {
643    // Fix-up referent, that isn't marked as an object field, for References.
644    ArtField* field = orig->GetClass()->FindInstanceField("referent", "Ljava/lang/Object;");
645    MemberOffset field_offset = field->GetOffset();
646    const Object* ref = orig->GetFieldObject<const Object*>(field_offset, false);
647    // Use SetFieldPtr to avoid card marking since we are writing to the image.
648    copy->SetFieldPtr(field_offset, GetImageAddress(ref), false);
649  }
650}
651
652static ArtMethod* GetTargetMethod(const CompilerDriver::PatchInformation* patch)
653    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
654  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
655  DexCache* dex_cache = class_linker->FindDexCache(patch->GetDexFile());
656  ArtMethod* method = class_linker->ResolveMethod(patch->GetDexFile(),
657                                                  patch->GetTargetMethodIdx(),
658                                                  dex_cache,
659                                                  NULL,
660                                                  NULL,
661                                                  patch->GetTargetInvokeType());
662  CHECK(method != NULL)
663    << patch->GetDexFile().GetLocation() << " " << patch->GetTargetMethodIdx();
664  CHECK(!method->IsRuntimeMethod())
665    << patch->GetDexFile().GetLocation() << " " << patch->GetTargetMethodIdx();
666  CHECK(dex_cache->GetResolvedMethods()->Get(patch->GetTargetMethodIdx()) == method)
667    << patch->GetDexFile().GetLocation() << " " << patch->GetReferrerMethodIdx() << " "
668    << PrettyMethod(dex_cache->GetResolvedMethods()->Get(patch->GetTargetMethodIdx())) << " "
669    << PrettyMethod(method);
670  return method;
671}
672
673void ImageWriter::PatchOatCodeAndMethods() {
674  Thread* self = Thread::Current();
675  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
676  const char* old_cause = self->StartAssertNoThreadSuspension("ImageWriter");
677
678  typedef std::vector<const CompilerDriver::PatchInformation*> Patches;
679  const Patches& code_to_patch = compiler_driver_.GetCodeToPatch();
680  for (size_t i = 0; i < code_to_patch.size(); i++) {
681    const CompilerDriver::PatchInformation* patch = code_to_patch[i];
682    ArtMethod* target = GetTargetMethod(patch);
683    uint32_t code = reinterpret_cast<uint32_t>(class_linker->GetOatCodeFor(target));
684    uint32_t code_base = reinterpret_cast<uint32_t>(&oat_file_->GetOatHeader());
685    uint32_t code_offset = code - code_base;
686    SetPatchLocation(patch, reinterpret_cast<uint32_t>(GetOatAddress(code_offset)));
687  }
688
689  const Patches& methods_to_patch = compiler_driver_.GetMethodsToPatch();
690  for (size_t i = 0; i < methods_to_patch.size(); i++) {
691    const CompilerDriver::PatchInformation* patch = methods_to_patch[i];
692    ArtMethod* target = GetTargetMethod(patch);
693    SetPatchLocation(patch, reinterpret_cast<uint32_t>(GetImageAddress(target)));
694  }
695
696  // Update the image header with the new checksum after patching
697  ImageHeader* image_header = reinterpret_cast<ImageHeader*>(image_->Begin());
698  image_header->SetOatChecksum(oat_file_->GetOatHeader().GetChecksum());
699  self->EndAssertNoThreadSuspension(old_cause);
700}
701
702void ImageWriter::SetPatchLocation(const CompilerDriver::PatchInformation* patch, uint32_t value) {
703  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
704  const void* oat_code = class_linker->GetOatCodeFor(patch->GetDexFile(),
705                                                     patch->GetReferrerClassDefIdx(),
706                                                     patch->GetReferrerMethodIdx());
707  OatHeader& oat_header = const_cast<OatHeader&>(oat_file_->GetOatHeader());
708  // TODO: make this Thumb2 specific
709  uint8_t* base = reinterpret_cast<uint8_t*>(reinterpret_cast<uint32_t>(oat_code) & ~0x1);
710  uint32_t* patch_location = reinterpret_cast<uint32_t*>(base + patch->GetLiteralOffset());
711#ifndef NDEBUG
712  const DexFile::MethodId& id = patch->GetDexFile().GetMethodId(patch->GetTargetMethodIdx());
713  uint32_t expected = reinterpret_cast<uint32_t>(&id);
714  uint32_t actual = *patch_location;
715  CHECK(actual == expected || actual == value) << std::hex
716    << "actual=" << actual
717    << "expected=" << expected
718    << "value=" << value;
719#endif
720  *patch_location = value;
721  oat_header.UpdateChecksum(patch_location, sizeof(value));
722}
723
724}  // namespace art
725