image_writer.cc revision 637c65b1e431fd90195b71c141b3590bd81cc91a 
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 "compiler/driver/compiler_driver.h"
28#include "dex_file-inl.h"
29#include "gc/card_table-inl.h"
30#include "gc/large_object_space.h"
31#include "gc/space.h"
32#include "globals.h"
33#include "heap.h"
34#include "image.h"
35#include "intern_table.h"
36#include "mirror/array-inl.h"
37#include "mirror/class-inl.h"
38#include "mirror/class_loader.h"
39#include "mirror/dex_cache-inl.h"
40#include "mirror/field-inl.h"
41#include "mirror/abstract_method-inl.h"
42#include "mirror/object-inl.h"
43#include "mirror/object_array-inl.h"
44#include "oat.h"
45#include "oat_file.h"
46#include "object_utils.h"
47#include "runtime.h"
48#include "scoped_thread_state_change.h"
49#include "sirt_ref.h"
50#include "UniquePtr.h"
51#include "utils.h"
52
53using namespace art::mirror;
54
55namespace art {
56
57bool ImageWriter::Write(const std::string& image_filename,
58                        uintptr_t image_begin,
59                        const std::string& oat_filename,
60                        const std::string& oat_location,
61                        const CompilerDriver& compiler_driver) {
62  CHECK(!image_filename.empty());
63
64  CHECK_NE(image_begin, 0U);
65  image_begin_ = reinterpret_cast<byte*>(image_begin);
66
67  Heap* heap = Runtime::Current()->GetHeap();
68  const Spaces& spaces = heap->GetSpaces();
69
70  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
71  const std::vector<DexCache*>& all_dex_caches = class_linker->GetDexCaches();
72  for (size_t i = 0; i < all_dex_caches.size(); i++) {
73    DexCache* dex_cache = all_dex_caches[i];
74    dex_caches_.insert(dex_cache);
75  }
76
77  UniquePtr<File> oat_file(OS::OpenFile(oat_filename.c_str(), true, false));
78  if (oat_file.get() == NULL) {
79    LOG(ERROR) << "Failed to open oat file " << oat_filename << " for " << oat_location;
80    return false;
81  }
82  oat_file_ = OatFile::OpenWritable(oat_file.get(), oat_location);
83  class_linker->RegisterOatFile(*oat_file_);
84
85  {
86    Thread::Current()->TransitionFromSuspendedToRunnable();
87    PruneNonImageClasses();  // Remove junk
88    ComputeLazyFieldsForImageClasses();  // Add useful information
89    ComputeEagerResolvedStrings();
90    Thread::Current()->TransitionFromRunnableToSuspended(kNative);
91  }
92  heap->CollectGarbage(false);  // Remove garbage
93  // Trim size of alloc spaces
94  // TODO: C++0x auto
95  for (Spaces::const_iterator cur = spaces.begin(); cur != spaces.end(); ++cur) {
96    if ((*cur)->IsAllocSpace()) {
97      (*cur)->AsAllocSpace()->Trim();
98    }
99  }
100
101  if (!AllocMemory()) {
102    return false;
103  }
104#ifndef NDEBUG
105  {
106    ScopedObjectAccess soa(Thread::Current());
107    CheckNonImageClassesRemoved();
108  }
109#endif
110  Thread::Current()->TransitionFromSuspendedToRunnable();
111  size_t oat_loaded_size = 0;
112  size_t oat_data_offset = 0;
113  compiler_driver.GetOatElfInformation(oat_file.get(), oat_loaded_size, oat_data_offset);
114  CalculateNewObjectOffsets(oat_loaded_size, oat_data_offset);
115  CopyAndFixupObjects();
116  PatchOatCodeAndMethods(compiler_driver);
117  Thread::Current()->TransitionFromRunnableToSuspended(kNative);
118
119  UniquePtr<File> image_file(OS::OpenFile(image_filename.c_str(), true));
120  if (image_file.get() == NULL) {
121    LOG(ERROR) << "Failed to open image file " << image_filename;
122    return false;
123  }
124  if (fchmod(image_file->Fd(), 0644) != 0) {
125    PLOG(ERROR) << "Failed to make image file world readable: " << image_filename;
126    return EXIT_FAILURE;
127  }
128  bool success = image_file->WriteFully(image_->Begin(), image_end_);
129  if (!success) {
130    PLOG(ERROR) << "Failed to write image file " << image_filename;
131    return false;
132  }
133  return true;
134}
135
136bool ImageWriter::AllocMemory() {
137  const Spaces& spaces = Runtime::Current()->GetHeap()->GetSpaces();
138  size_t size = 0;
139  for (Spaces::const_iterator it = spaces.begin(); it != spaces.end(); ++it) {
140    if ((*it)->IsAllocSpace()) {
141      size += (*it)->Size();
142    }
143  }
144
145  int prot = PROT_READ | PROT_WRITE;
146  size_t length = RoundUp(size, kPageSize);
147  image_.reset(MemMap::MapAnonymous("image writer image", NULL, length, prot));
148  if (image_.get() == NULL) {
149    LOG(ERROR) << "Failed to allocate memory for image file generation";
150    return false;
151  }
152  return true;
153}
154
155void ImageWriter::ComputeLazyFieldsForImageClasses() {
156  Runtime* runtime = Runtime::Current();
157  ClassLinker* class_linker = runtime->GetClassLinker();
158  class_linker->VisitClassesWithoutClassesLock(ComputeLazyFieldsForClassesVisitor, NULL);
159}
160
161bool ImageWriter::ComputeLazyFieldsForClassesVisitor(Class* c, void* /*arg*/) {
162  c->ComputeName();
163  return true;
164}
165
166void ImageWriter::ComputeEagerResolvedStringsCallback(Object* obj, void* arg) {
167  if (!obj->GetClass()->IsStringClass()) {
168    return;
169  }
170  String* string = obj->AsString();
171  const uint16_t* utf16_string = string->GetCharArray()->GetData() + string->GetOffset();
172  ImageWriter* writer = reinterpret_cast<ImageWriter*>(arg);
173  typedef Set::const_iterator CacheIt;  // TODO: C++0x auto
174  for (CacheIt it = writer->dex_caches_.begin(), end = writer->dex_caches_.end(); it != end; ++it) {
175    DexCache* dex_cache = *it;
176    const DexFile& dex_file = *dex_cache->GetDexFile();
177    const DexFile::StringId* string_id = dex_file.FindStringId(utf16_string);
178    if (string_id != NULL) {
179      // This string occurs in this dex file, assign the dex cache entry.
180      uint32_t string_idx = dex_file.GetIndexForStringId(*string_id);
181      if (dex_cache->GetResolvedString(string_idx) == NULL) {
182        dex_cache->SetResolvedString(string_idx, string);
183      }
184    }
185  }
186}
187
188void ImageWriter::ComputeEagerResolvedStrings()
189    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
190  // TODO: Check image spaces only?
191  Heap* heap = Runtime::Current()->GetHeap();
192  WriterMutexLock mu(Thread::Current(), *Locks::heap_bitmap_lock_);
193  heap->FlushAllocStack();
194  heap->GetLiveBitmap()->Walk(ComputeEagerResolvedStringsCallback, this);
195}
196
197bool ImageWriter::IsImageClass(const Class* klass) {
198  if (image_classes_ == NULL) {
199    return true;
200  }
201  while (klass->IsArrayClass()) {
202    klass = klass->GetComponentType();
203  }
204  if (klass->IsPrimitive()) {
205    return true;
206  }
207  const std::string descriptor(ClassHelper(klass).GetDescriptor());
208  return image_classes_->find(descriptor) != image_classes_->end();
209}
210
211
212struct NonImageClasses {
213  ImageWriter* image_writer;
214  std::set<std::string>* non_image_classes;
215};
216
217void ImageWriter::PruneNonImageClasses() {
218  if (image_classes_ == NULL) {
219    return;
220  }
221  Runtime* runtime = Runtime::Current();
222  ClassLinker* class_linker = runtime->GetClassLinker();
223
224  std::set<std::string> non_image_classes;
225  NonImageClasses context;
226  context.image_writer = this;
227  context.non_image_classes = &non_image_classes;
228  class_linker->VisitClasses(NonImageClassesVisitor, &context);
229
230  typedef std::set<std::string>::const_iterator ClassIt;  // TODO: C++0x auto
231  for (ClassIt it = non_image_classes.begin(), end = non_image_classes.end(); it != end; ++it) {
232    class_linker->RemoveClass((*it).c_str(), NULL);
233  }
234
235  AbstractMethod* resolution_method = runtime->GetResolutionMethod();
236  typedef Set::const_iterator CacheIt;  // TODO: C++0x auto
237  for (CacheIt it = dex_caches_.begin(), end = dex_caches_.end(); it != end; ++it) {
238    DexCache* dex_cache = *it;
239    for (size_t i = 0; i < dex_cache->NumResolvedTypes(); i++) {
240      Class* klass = dex_cache->GetResolvedType(i);
241      if (klass != NULL && !IsImageClass(klass)) {
242        dex_cache->SetResolvedType(i, NULL);
243        dex_cache->GetInitializedStaticStorage()->Set(i, NULL);
244      }
245    }
246    for (size_t i = 0; i < dex_cache->NumResolvedMethods(); i++) {
247      AbstractMethod* method = dex_cache->GetResolvedMethod(i);
248      if (method != NULL && !IsImageClass(method->GetDeclaringClass())) {
249        dex_cache->SetResolvedMethod(i, resolution_method);
250      }
251    }
252    for (size_t i = 0; i < dex_cache->NumResolvedFields(); i++) {
253      Field* field = dex_cache->GetResolvedField(i);
254      if (field != NULL && !IsImageClass(field->GetDeclaringClass())) {
255        dex_cache->SetResolvedField(i, NULL);
256      }
257    }
258  }
259}
260
261bool ImageWriter::NonImageClassesVisitor(Class* klass, void* arg) {
262  NonImageClasses* context = reinterpret_cast<NonImageClasses*>(arg);
263  if (!context->image_writer->IsImageClass(klass)) {
264    context->non_image_classes->insert(ClassHelper(klass).GetDescriptor());
265  }
266  return true;
267}
268
269void ImageWriter::CheckNonImageClassesRemoved()
270    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
271  if (image_classes_ == NULL) {
272    return;
273  }
274
275  Heap* heap = Runtime::Current()->GetHeap();
276  Thread* self = Thread::Current();
277  {
278    WriterMutexLock mu(self, *Locks::heap_bitmap_lock_);
279    heap->FlushAllocStack();
280  }
281
282  ReaderMutexLock mu(self, *Locks::heap_bitmap_lock_);
283  heap->GetLiveBitmap()->Walk(CheckNonImageClassesRemovedCallback, this);
284}
285
286void ImageWriter::CheckNonImageClassesRemovedCallback(Object* obj, void* arg) {
287  ImageWriter* image_writer = reinterpret_cast<ImageWriter*>(arg);
288  if (!obj->IsClass()) {
289    return;
290  }
291  Class* klass = obj->AsClass();
292  if (!image_writer->IsImageClass(klass)) {
293    image_writer->DumpImageClasses();
294    CHECK(image_writer->IsImageClass(klass)) << ClassHelper(klass).GetDescriptor()
295                                             << " " << PrettyDescriptor(klass);
296  }
297}
298
299void ImageWriter::DumpImageClasses() {
300  typedef std::set<std::string>::const_iterator It;  // TODO: C++0x auto
301  for (It it = image_classes_->begin(), end = image_classes_->end(); it != end; ++it) {
302    LOG(INFO) << " " << *it;
303  }
304}
305
306void ImageWriter::CalculateNewObjectOffsetsCallback(Object* obj, void* arg) {
307  DCHECK(obj != NULL);
308  DCHECK(arg != NULL);
309  ImageWriter* image_writer = reinterpret_cast<ImageWriter*>(arg);
310
311  // if it is a string, we want to intern it if its not interned.
312  if (obj->GetClass()->IsStringClass()) {
313    // we must be an interned string that was forward referenced and already assigned
314    if (image_writer->IsImageOffsetAssigned(obj)) {
315      DCHECK_EQ(obj, obj->AsString()->Intern());
316      return;
317    }
318    SirtRef<String> interned(Thread::Current(), obj->AsString()->Intern());
319    if (obj != interned.get()) {
320      if (!image_writer->IsImageOffsetAssigned(interned.get())) {
321        // interned obj is after us, allocate its location early
322        image_writer->AssignImageOffset(interned.get());
323      }
324      // point those looking for this object to the interned version.
325      image_writer->SetImageOffset(obj, image_writer->GetImageOffset(interned.get()));
326      return;
327    }
328    // else (obj == interned), nothing to do but fall through to the normal case
329  }
330
331  image_writer->AssignImageOffset(obj);
332}
333
334ObjectArray<Object>* ImageWriter::CreateImageRoots() const {
335  Runtime* runtime = Runtime::Current();
336  ClassLinker* class_linker = runtime->GetClassLinker();
337  Class* object_array_class = class_linker->FindSystemClass("[Ljava/lang/Object;");
338  Thread* self = Thread::Current();
339
340  // build an Object[] of all the DexCaches used in the source_space_
341  ObjectArray<Object>* dex_caches = ObjectArray<Object>::Alloc(self, object_array_class,
342                                                               dex_caches_.size());
343  int i = 0;
344  typedef Set::const_iterator It;  // TODO: C++0x auto
345  for (It it = dex_caches_.begin(), end = dex_caches_.end(); it != end; ++it, ++i) {
346    dex_caches->Set(i, *it);
347  }
348
349  // build an Object[] of the roots needed to restore the runtime
350  SirtRef<ObjectArray<Object> >
351      image_roots(self,
352                  ObjectArray<Object>::Alloc(self, object_array_class,
353                                             ImageHeader::kImageRootsMax));
354  image_roots->Set(ImageHeader::kResolutionMethod, runtime->GetResolutionMethod());
355  image_roots->Set(ImageHeader::kCalleeSaveMethod,
356                   runtime->GetCalleeSaveMethod(Runtime::kSaveAll));
357  image_roots->Set(ImageHeader::kRefsOnlySaveMethod,
358                   runtime->GetCalleeSaveMethod(Runtime::kRefsOnly));
359  image_roots->Set(ImageHeader::kRefsAndArgsSaveMethod,
360                   runtime->GetCalleeSaveMethod(Runtime::kRefsAndArgs));
361  image_roots->Set(ImageHeader::kOatLocation,
362                   String::AllocFromModifiedUtf8(self, oat_file_->GetLocation().c_str()));
363  image_roots->Set(ImageHeader::kDexCaches,
364                   dex_caches);
365  image_roots->Set(ImageHeader::kClassRoots,
366                   class_linker->GetClassRoots());
367  for (int i = 0; i < ImageHeader::kImageRootsMax; i++) {
368    CHECK(image_roots->Get(i) != NULL);
369  }
370  return image_roots.get();
371}
372
373void ImageWriter::CalculateNewObjectOffsets(size_t oat_loaded_size, size_t oat_data_offset) {
374  CHECK_NE(0U, oat_loaded_size);
375  Thread* self = Thread::Current();
376  SirtRef<ObjectArray<Object> > image_roots(self, CreateImageRoots());
377
378  Heap* heap = Runtime::Current()->GetHeap();
379  const Spaces& spaces = heap->GetSpaces();
380  DCHECK(!spaces.empty());
381  DCHECK_EQ(0U, image_end_);
382
383  // leave space for the header, but do not write it yet, we need to
384  // know where image_roots is going to end up
385  image_end_ += RoundUp(sizeof(ImageHeader), 8); // 64-bit-alignment
386
387  {
388    WriterMutexLock mu(self, *Locks::heap_bitmap_lock_);
389    heap->FlushAllocStack();
390    // TODO: Image spaces only?
391    // TODO: Add InOrderWalk to heap bitmap.
392    const char* old = self->StartAssertNoThreadSuspension("ImageWriter");
393    DCHECK(heap->GetLargeObjectsSpace()->GetLiveObjects()->IsEmpty());
394    for (Spaces::const_iterator it = spaces.begin(); it != spaces.end(); ++it) {
395      (*it)->GetLiveBitmap()->InOrderWalk(CalculateNewObjectOffsetsCallback, this);
396      DCHECK_LT(image_end_, image_->Size());
397    }
398    self->EndAssertNoThreadSuspension(old);
399  }
400
401  const byte* oat_file_begin = image_begin_ + RoundUp(image_end_, kPageSize);
402  const byte* oat_file_end = oat_file_begin + oat_loaded_size;
403  oat_data_begin_ = oat_file_begin + oat_data_offset;
404  const byte* oat_data_end = oat_data_begin_ + oat_file_->Size();
405
406  // return to write header at start of image with future location of image_roots
407  ImageHeader image_header(reinterpret_cast<uint32_t>(image_begin_),
408                           reinterpret_cast<uint32_t>(GetImageAddress(image_roots.get())),
409                           oat_file_->GetOatHeader().GetChecksum(),
410                           reinterpret_cast<uint32_t>(oat_file_begin),
411                           reinterpret_cast<uint32_t>(oat_data_begin_),
412                           reinterpret_cast<uint32_t>(oat_data_end),
413                           reinterpret_cast<uint32_t>(oat_file_end));
414  memcpy(image_->Begin(), &image_header, sizeof(image_header));
415
416  // Note that image_end_ is left at end of used space
417}
418
419void ImageWriter::CopyAndFixupObjects()
420    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
421  Thread* self = Thread::Current();
422  const char* old_cause = self->StartAssertNoThreadSuspension("ImageWriter");
423  Heap* heap = Runtime::Current()->GetHeap();
424  // TODO: heap validation can't handle this fix up pass
425  heap->DisableObjectValidation();
426  // TODO: Image spaces only?
427  WriterMutexLock mu(self, *Locks::heap_bitmap_lock_);
428  heap->FlushAllocStack();
429  heap->GetLiveBitmap()->Walk(CopyAndFixupObjectsCallback, this);
430  self->EndAssertNoThreadSuspension(old_cause);
431}
432
433void ImageWriter::CopyAndFixupObjectsCallback(Object* object, void* arg) {
434  DCHECK(object != NULL);
435  DCHECK(arg != NULL);
436  const Object* obj = object;
437  ImageWriter* image_writer = reinterpret_cast<ImageWriter*>(arg);
438
439  // see GetLocalAddress for similar computation
440  size_t offset = image_writer->GetImageOffset(obj);
441  byte* dst = image_writer->image_->Begin() + offset;
442  const byte* src = reinterpret_cast<const byte*>(obj);
443  size_t n = obj->SizeOf();
444  DCHECK_LT(offset + n, image_writer->image_->Size());
445  memcpy(dst, src, n);
446  Object* copy = reinterpret_cast<Object*>(dst);
447  copy->SetField32(Object::MonitorOffset(), 0, false); // We may have inflated the lock during compilation.
448  image_writer->FixupObject(obj, copy);
449}
450
451void ImageWriter::FixupObject(const Object* orig, Object* copy) {
452  DCHECK(orig != NULL);
453  DCHECK(copy != NULL);
454  copy->SetClass(down_cast<Class*>(GetImageAddress(orig->GetClass())));
455  // TODO: special case init of pointers to malloc data (or removal of these pointers)
456  if (orig->IsClass()) {
457    FixupClass(orig->AsClass(), down_cast<Class*>(copy));
458  } else if (orig->IsObjectArray()) {
459    FixupObjectArray(orig->AsObjectArray<Object>(), down_cast<ObjectArray<Object>*>(copy));
460  } else if (orig->IsMethod()) {
461    FixupMethod(orig->AsMethod(), down_cast<AbstractMethod*>(copy));
462  } else {
463    FixupInstanceFields(orig, copy);
464  }
465}
466
467void ImageWriter::FixupClass(const Class* orig, Class* copy) {
468  FixupInstanceFields(orig, copy);
469  FixupStaticFields(orig, copy);
470}
471
472void ImageWriter::FixupMethod(const AbstractMethod* orig, AbstractMethod* copy) {
473  FixupInstanceFields(orig, copy);
474
475  // OatWriter replaces the code_ with an offset value.
476  // Here we readjust to a pointer relative to oat_begin_
477  if (orig->IsAbstract()) {
478    // Code for abstract methods is set to the abstract method error stub when we load the image.
479    copy->SetEntryPointFromCompiledCode(NULL);
480    return;
481  }
482
483  if (orig == Runtime::Current()->GetResolutionMethod()) {
484    // The resolution method's code is set to the resolution trampoline when we load the image.
485    copy->SetEntryPointFromCompiledCode(NULL);
486    return;
487  }
488
489  // Non-abstract methods have code
490  copy->SetEntryPointFromCompiledCode(GetOatAddress(orig->GetOatCodeOffset()));
491
492  if (orig->IsNative()) {
493    // The native method's pointer is set to a stub to lookup via dlsym when we load the image.
494    // Note this is not the code_ pointer, that is handled above.
495    copy->SetNativeMethod(NULL);
496  } else {
497    // normal (non-abstract non-native) methods have mapping tables to relocate
498    uint32_t mapping_table_off = orig->GetOatMappingTableOffset();
499    const byte* mapping_table = GetOatAddress(mapping_table_off);
500    copy->SetMappingTable(reinterpret_cast<const uint32_t*>(mapping_table));
501
502    uint32_t vmap_table_offset = orig->GetOatVmapTableOffset();
503    const byte* vmap_table = GetOatAddress(vmap_table_offset);
504    copy->SetVmapTable(reinterpret_cast<const uint16_t*>(vmap_table));
505
506    uint32_t native_gc_map_offset = orig->GetOatNativeGcMapOffset();
507    const byte* native_gc_map = GetOatAddress(native_gc_map_offset);
508    copy->SetNativeGcMap(reinterpret_cast<const uint8_t*>(native_gc_map));
509  }
510}
511
512void ImageWriter::FixupObjectArray(const ObjectArray<Object>* orig, ObjectArray<Object>* copy) {
513  for (int32_t i = 0; i < orig->GetLength(); ++i) {
514    const Object* element = orig->Get(i);
515    copy->SetPtrWithoutChecks(i, GetImageAddress(element));
516  }
517}
518
519void ImageWriter::FixupInstanceFields(const Object* orig, Object* copy) {
520  DCHECK(orig != NULL);
521  DCHECK(copy != NULL);
522  Class* klass = orig->GetClass();
523  DCHECK(klass != NULL);
524  FixupFields(orig,
525              copy,
526              klass->GetReferenceInstanceOffsets(),
527              false);
528}
529
530void ImageWriter::FixupStaticFields(const Class* orig, Class* copy) {
531  DCHECK(orig != NULL);
532  DCHECK(copy != NULL);
533  FixupFields(orig,
534              copy,
535              orig->GetReferenceStaticOffsets(),
536              true);
537}
538
539void ImageWriter::FixupFields(const Object* orig,
540                              Object* copy,
541                              uint32_t ref_offsets,
542                              bool is_static) {
543  if (ref_offsets != CLASS_WALK_SUPER) {
544    // Found a reference offset bitmap.  Fixup the specified offsets.
545    while (ref_offsets != 0) {
546      size_t right_shift = CLZ(ref_offsets);
547      MemberOffset byte_offset = CLASS_OFFSET_FROM_CLZ(right_shift);
548      const Object* ref = orig->GetFieldObject<const Object*>(byte_offset, false);
549      // Use SetFieldPtr to avoid card marking since we are writing to the image.
550      copy->SetFieldPtr(byte_offset, GetImageAddress(ref), false);
551      ref_offsets &= ~(CLASS_HIGH_BIT >> right_shift);
552    }
553  } else {
554    // There is no reference offset bitmap.  In the non-static case,
555    // walk up the class inheritance hierarchy and find reference
556    // offsets the hard way. In the static case, just consider this
557    // class.
558    for (const Class *klass = is_static ? orig->AsClass() : orig->GetClass();
559         klass != NULL;
560         klass = is_static ? NULL : klass->GetSuperClass()) {
561      size_t num_reference_fields = (is_static
562                                     ? klass->NumReferenceStaticFields()
563                                     : klass->NumReferenceInstanceFields());
564      for (size_t i = 0; i < num_reference_fields; ++i) {
565        Field* field = (is_static
566                        ? klass->GetStaticField(i)
567                        : klass->GetInstanceField(i));
568        MemberOffset field_offset = field->GetOffset();
569        const Object* ref = orig->GetFieldObject<const Object*>(field_offset, false);
570        // Use SetFieldPtr to avoid card marking since we are writing to the image.
571        copy->SetFieldPtr(field_offset, GetImageAddress(ref), false);
572      }
573    }
574  }
575  if (!is_static && orig->IsReferenceInstance()) {
576    // Fix-up referent, that isn't marked as an object field, for References.
577    Field* field = orig->GetClass()->FindInstanceField("referent", "Ljava/lang/Object;");
578    MemberOffset field_offset = field->GetOffset();
579    const Object* ref = orig->GetFieldObject<const Object*>(field_offset, false);
580    // Use SetFieldPtr to avoid card marking since we are writing to the image.
581    copy->SetFieldPtr(field_offset, GetImageAddress(ref), false);
582  }
583}
584
585static AbstractMethod* GetTargetMethod(const CompilerDriver::PatchInformation* patch)
586    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
587  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
588  DexCache* dex_cache = class_linker->FindDexCache(patch->GetDexFile());
589  AbstractMethod* method = class_linker->ResolveMethod(patch->GetDexFile(),
590                                               patch->GetTargetMethodIdx(),
591                                               dex_cache,
592                                               NULL,
593                                               NULL,
594                                               patch->GetTargetInvokeType());
595  CHECK(method != NULL)
596    << patch->GetDexFile().GetLocation() << " " << patch->GetTargetMethodIdx();
597  CHECK(!method->IsRuntimeMethod())
598    << patch->GetDexFile().GetLocation() << " " << patch->GetTargetMethodIdx();
599  CHECK(dex_cache->GetResolvedMethods()->Get(patch->GetTargetMethodIdx()) == method)
600    << patch->GetDexFile().GetLocation() << " " << patch->GetReferrerMethodIdx() << " "
601    << PrettyMethod(dex_cache->GetResolvedMethods()->Get(patch->GetTargetMethodIdx())) << " "
602    << PrettyMethod(method);
603  return method;
604}
605
606void ImageWriter::PatchOatCodeAndMethods(const CompilerDriver& compiler) {
607  Thread* self = Thread::Current();
608  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
609  const char* old_cause = self->StartAssertNoThreadSuspension("ImageWriter");
610
611  typedef std::vector<const CompilerDriver::PatchInformation*> Patches;
612  const Patches& code_to_patch = compiler.GetCodeToPatch();
613  for (size_t i = 0; i < code_to_patch.size(); i++) {
614    const CompilerDriver::PatchInformation* patch = code_to_patch[i];
615    AbstractMethod* target = GetTargetMethod(patch);
616    uint32_t code = reinterpret_cast<uint32_t>(class_linker->GetOatCodeFor(target));
617    uint32_t code_base = reinterpret_cast<uint32_t>(&oat_file_->GetOatHeader());
618    uint32_t code_offset = code - code_base;
619    SetPatchLocation(patch, reinterpret_cast<uint32_t>(GetOatAddress(code_offset)));
620  }
621
622  const Patches& methods_to_patch = compiler.GetMethodsToPatch();
623  for (size_t i = 0; i < methods_to_patch.size(); i++) {
624    const CompilerDriver::PatchInformation* patch = methods_to_patch[i];
625    AbstractMethod* target = GetTargetMethod(patch);
626    SetPatchLocation(patch, reinterpret_cast<uint32_t>(GetImageAddress(target)));
627  }
628
629  // Update the image header with the new checksum after patching
630  ImageHeader* image_header = reinterpret_cast<ImageHeader*>(image_->Begin());
631  image_header->SetOatChecksum(oat_file_->GetOatHeader().GetChecksum());
632  self->EndAssertNoThreadSuspension(old_cause);
633}
634
635void ImageWriter::SetPatchLocation(const CompilerDriver::PatchInformation* patch, uint32_t value) {
636  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
637  const void* oat_code = class_linker->GetOatCodeFor(patch->GetDexFile(),
638                                                     patch->GetReferrerMethodIdx());
639  OatHeader& oat_header = const_cast<OatHeader&>(oat_file_->GetOatHeader());
640  // TODO: make this Thumb2 specific
641  uint8_t* base = reinterpret_cast<uint8_t*>(reinterpret_cast<uint32_t>(oat_code) & ~0x1);
642  uint32_t* patch_location = reinterpret_cast<uint32_t*>(base + patch->GetLiteralOffset());
643#ifndef NDEBUG
644  const DexFile::MethodId& id = patch->GetDexFile().GetMethodId(patch->GetTargetMethodIdx());
645  uint32_t expected = reinterpret_cast<uint32_t>(&id);
646  uint32_t actual = *patch_location;
647  CHECK(actual == expected || actual == value) << std::hex
648    << "actual=" << actual
649    << "expected=" << expected
650    << "value=" << value;
651#endif
652  *patch_location = value;
653  oat_header.UpdateChecksum(patch_location, sizeof(value));
654}
655
656}  // namespace art
657