image_writer.cc revision 468532ea115657709bc32ee498e701a4c71762d4 
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/heap.h"
33#include "gc/space/large_object_space.h"
34#include "gc/space/space-inl.h"
35#include "globals.h"
36#include "image.h"
37#include "intern_table.h"
38#include "mirror/array-inl.h"
39#include "mirror/class-inl.h"
40#include "mirror/class_loader.h"
41#include "mirror/dex_cache-inl.h"
42#include "mirror/field-inl.h"
43#include "mirror/abstract_method-inl.h"
44#include "mirror/object-inl.h"
45#include "mirror/object_array-inl.h"
46#include "oat.h"
47#include "oat_file.h"
48#include "object_utils.h"
49#include "runtime.h"
50#include "scoped_thread_state_change.h"
51#include "sirt_ref.h"
52#include "UniquePtr.h"
53#include "utils.h"
54
55using ::art::mirror::AbstractMethod;
56using ::art::mirror::Class;
57using ::art::mirror::DexCache;
58using ::art::mirror::EntryPointFromInterpreter;
59using ::art::mirror::Field;
60using ::art::mirror::Object;
61using ::art::mirror::ObjectArray;
62using ::art::mirror::String;
63
64namespace art {
65
66bool ImageWriter::Write(const std::string& image_filename,
67                        uintptr_t image_begin,
68                        const std::string& oat_filename,
69                        const std::string& oat_location) {
70  CHECK(!image_filename.empty());
71
72  CHECK_NE(image_begin, 0U);
73  image_begin_ = reinterpret_cast<byte*>(image_begin);
74
75  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
76  const std::vector<DexCache*>& all_dex_caches = class_linker->GetDexCaches();
77  for (size_t i = 0; i < all_dex_caches.size(); i++) {
78    DexCache* dex_cache = all_dex_caches[i];
79    dex_caches_.insert(dex_cache);
80  }
81
82  UniquePtr<File> oat_file(OS::OpenFile(oat_filename.c_str(), true, false));
83  if (oat_file.get() == NULL) {
84    LOG(ERROR) << "Failed to open oat file " << oat_filename << " for " << oat_location;
85    return false;
86  }
87  oat_file_ = OatFile::OpenWritable(oat_file.get(), oat_location);
88  if (oat_file_ == NULL) {
89    LOG(ERROR) << "Failed to open writable oat file " << oat_filename << " for " << oat_location;
90    return false;
91  }
92  class_linker->RegisterOatFile(*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  const std::vector<gc::space::ContinuousSpace*>& spaces = heap->GetContinuousSpaces();
121  // TODO: C++0x auto
122  typedef std::vector<gc::space::ContinuousSpace*>::const_iterator It;
123  for (It it = spaces.begin(), end = spaces.end(); it != end; ++it) {
124    gc::space::ContinuousSpace* space = *it;
125    if (space->IsDlMallocSpace()) {
126      space->AsDlMallocSpace()->Trim();
127    }
128  }
129
130  if (!AllocMemory()) {
131    return false;
132  }
133#ifndef NDEBUG
134  {  // NOLINT(whitespace/braces)
135    ScopedObjectAccess soa(Thread::Current());
136    CheckNonImageClassesRemoved();
137  }
138#endif
139  Thread::Current()->TransitionFromSuspendedToRunnable();
140  size_t oat_loaded_size = 0;
141  size_t oat_data_offset = 0;
142  ElfWriter::GetOatElfInformation(oat_file.get(), oat_loaded_size, oat_data_offset);
143  CalculateNewObjectOffsets(oat_loaded_size, oat_data_offset);
144  CopyAndFixupObjects();
145  PatchOatCodeAndMethods();
146  Thread::Current()->TransitionFromRunnableToSuspended(kNative);
147
148  UniquePtr<File> image_file(OS::OpenFile(image_filename.c_str(), true));
149  if (image_file.get() == NULL) {
150    LOG(ERROR) << "Failed to open image file " << image_filename;
151    return false;
152  }
153  if (fchmod(image_file->Fd(), 0644) != 0) {
154    PLOG(ERROR) << "Failed to make image file world readable: " << image_filename;
155    return EXIT_FAILURE;
156  }
157  bool success = image_file->WriteFully(image_->Begin(), image_end_);
158  if (!success) {
159    PLOG(ERROR) << "Failed to write image file " << image_filename;
160    return false;
161  }
162  return true;
163}
164
165bool ImageWriter::AllocMemory() {
166  gc::Heap* heap = Runtime::Current()->GetHeap();
167  const std::vector<gc::space::ContinuousSpace*>& spaces = heap->GetContinuousSpaces();
168  size_t size = 0;
169  // TODO: C++0x auto
170  typedef std::vector<gc::space::ContinuousSpace*>::const_iterator It;
171  for (It it = spaces.begin(), end = spaces.end(); it != end; ++it) {
172    gc::space::ContinuousSpace* space = *it;
173    if (space->IsDlMallocSpace()) {
174      size += space->Size();
175    }
176  }
177
178  int prot = PROT_READ | PROT_WRITE;
179  size_t length = RoundUp(size, kPageSize);
180  image_.reset(MemMap::MapAnonymous("image writer image", NULL, length, prot));
181  if (image_.get() == NULL) {
182    LOG(ERROR) << "Failed to allocate memory for image file generation";
183    return false;
184  }
185  return true;
186}
187
188void ImageWriter::ComputeLazyFieldsForImageClasses() {
189  Runtime* runtime = Runtime::Current();
190  ClassLinker* class_linker = runtime->GetClassLinker();
191  class_linker->VisitClassesWithoutClassesLock(ComputeLazyFieldsForClassesVisitor, NULL);
192}
193
194bool ImageWriter::ComputeLazyFieldsForClassesVisitor(Class* c, void* /*arg*/) {
195  c->ComputeName();
196  return true;
197}
198
199void ImageWriter::ComputeEagerResolvedStringsCallback(Object* obj, void* arg) {
200  if (!obj->GetClass()->IsStringClass()) {
201    return;
202  }
203  String* string = obj->AsString();
204  const uint16_t* utf16_string = string->GetCharArray()->GetData() + string->GetOffset();
205  ImageWriter* writer = reinterpret_cast<ImageWriter*>(arg);
206  typedef Set::const_iterator CacheIt;  // TODO: C++0x auto
207  for (CacheIt it = writer->dex_caches_.begin(), end = writer->dex_caches_.end(); it != end; ++it) {
208    DexCache* dex_cache = *it;
209    const DexFile& dex_file = *dex_cache->GetDexFile();
210    const DexFile::StringId* string_id = dex_file.FindStringId(utf16_string);
211    if (string_id != NULL) {
212      // This string occurs in this dex file, assign the dex cache entry.
213      uint32_t string_idx = dex_file.GetIndexForStringId(*string_id);
214      if (dex_cache->GetResolvedString(string_idx) == NULL) {
215        dex_cache->SetResolvedString(string_idx, string);
216      }
217    }
218  }
219}
220
221void ImageWriter::ComputeEagerResolvedStrings()
222    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
223  // TODO: Check image spaces only?
224  gc::Heap* heap = Runtime::Current()->GetHeap();
225  WriterMutexLock mu(Thread::Current(), *Locks::heap_bitmap_lock_);
226  heap->FlushAllocStack();
227  heap->GetLiveBitmap()->Walk(ComputeEagerResolvedStringsCallback, this);
228}
229
230bool ImageWriter::IsImageClass(const Class* klass) {
231  return compiler_driver_.IsImageClass(ClassHelper(klass).GetDescriptor());
232}
233
234struct NonImageClasses {
235  ImageWriter* image_writer;
236  std::set<std::string>* non_image_classes;
237};
238
239void ImageWriter::PruneNonImageClasses() {
240  if (compiler_driver_.GetImageClasses() == NULL) {
241    return;
242  }
243  Runtime* runtime = Runtime::Current();
244  ClassLinker* class_linker = runtime->GetClassLinker();
245
246  // Make a list of classes we would like to prune.
247  std::set<std::string> non_image_classes;
248  NonImageClasses context;
249  context.image_writer = this;
250  context.non_image_classes = &non_image_classes;
251  class_linker->VisitClasses(NonImageClassesVisitor, &context);
252
253  // Remove the undesired classes from the class roots.
254  typedef std::set<std::string>::const_iterator ClassIt;  // TODO: C++0x auto
255  for (ClassIt it = non_image_classes.begin(), end = non_image_classes.end(); it != end; ++it) {
256    class_linker->RemoveClass((*it).c_str(), NULL);
257  }
258
259  // Clear references to removed classes from the DexCaches.
260  AbstractMethod* resolution_method = runtime->GetResolutionMethod();
261  typedef Set::const_iterator CacheIt;  // TODO: C++0x auto
262  for (CacheIt it = dex_caches_.begin(), end = dex_caches_.end(); it != end; ++it) {
263    DexCache* dex_cache = *it;
264    for (size_t i = 0; i < dex_cache->NumResolvedTypes(); i++) {
265      Class* klass = dex_cache->GetResolvedType(i);
266      if (klass != NULL && !IsImageClass(klass)) {
267        dex_cache->SetResolvedType(i, NULL);
268        dex_cache->GetInitializedStaticStorage()->Set(i, NULL);
269      }
270    }
271    for (size_t i = 0; i < dex_cache->NumResolvedMethods(); i++) {
272      AbstractMethod* method = dex_cache->GetResolvedMethod(i);
273      if (method != NULL && !IsImageClass(method->GetDeclaringClass())) {
274        dex_cache->SetResolvedMethod(i, resolution_method);
275      }
276    }
277    for (size_t i = 0; i < dex_cache->NumResolvedFields(); i++) {
278      Field* field = dex_cache->GetResolvedField(i);
279      if (field != NULL && !IsImageClass(field->GetDeclaringClass())) {
280        dex_cache->SetResolvedField(i, NULL);
281      }
282    }
283  }
284}
285
286bool ImageWriter::NonImageClassesVisitor(Class* klass, void* arg) {
287  NonImageClasses* context = reinterpret_cast<NonImageClasses*>(arg);
288  if (!context->image_writer->IsImageClass(klass)) {
289    context->non_image_classes->insert(ClassHelper(klass).GetDescriptor());
290  }
291  return true;
292}
293
294void ImageWriter::CheckNonImageClassesRemoved()
295    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
296  if (compiler_driver_.GetImageClasses() == NULL) {
297    return;
298  }
299
300  gc::Heap* heap = Runtime::Current()->GetHeap();
301  Thread* self = Thread::Current();
302  {
303    WriterMutexLock mu(self, *Locks::heap_bitmap_lock_);
304    heap->FlushAllocStack();
305  }
306
307  ReaderMutexLock mu(self, *Locks::heap_bitmap_lock_);
308  heap->GetLiveBitmap()->Walk(CheckNonImageClassesRemovedCallback, this);
309}
310
311void ImageWriter::CheckNonImageClassesRemovedCallback(Object* obj, void* arg) {
312  ImageWriter* image_writer = reinterpret_cast<ImageWriter*>(arg);
313  if (!obj->IsClass()) {
314    return;
315  }
316  Class* klass = obj->AsClass();
317  if (!image_writer->IsImageClass(klass)) {
318    image_writer->DumpImageClasses();
319    CHECK(image_writer->IsImageClass(klass)) << ClassHelper(klass).GetDescriptor()
320                                             << " " << PrettyDescriptor(klass);
321  }
322}
323
324void ImageWriter::DumpImageClasses() {
325  CompilerDriver::DescriptorSet* image_classes = compiler_driver_.GetImageClasses();
326  CHECK(image_classes != NULL);
327  typedef std::set<std::string>::const_iterator It;  // TODO: C++0x auto
328  for (It it = image_classes->begin(), end = image_classes->end(); it != end; ++it) {
329    LOG(INFO) << " " << *it;
330  }
331}
332
333void ImageWriter::CalculateNewObjectOffsetsCallback(Object* obj, void* arg) {
334  DCHECK(obj != NULL);
335  DCHECK(arg != NULL);
336  ImageWriter* image_writer = reinterpret_cast<ImageWriter*>(arg);
337
338  // if it is a string, we want to intern it if its not interned.
339  if (obj->GetClass()->IsStringClass()) {
340    // we must be an interned string that was forward referenced and already assigned
341    if (image_writer->IsImageOffsetAssigned(obj)) {
342      DCHECK_EQ(obj, obj->AsString()->Intern());
343      return;
344    }
345    SirtRef<String> interned(Thread::Current(), obj->AsString()->Intern());
346    if (obj != interned.get()) {
347      if (!image_writer->IsImageOffsetAssigned(interned.get())) {
348        // interned obj is after us, allocate its location early
349        image_writer->AssignImageOffset(interned.get());
350      }
351      // point those looking for this object to the interned version.
352      image_writer->SetImageOffset(obj, image_writer->GetImageOffset(interned.get()));
353      return;
354    }
355    // else (obj == interned), nothing to do but fall through to the normal case
356  }
357
358  image_writer->AssignImageOffset(obj);
359}
360
361ObjectArray<Object>* ImageWriter::CreateImageRoots() const {
362  Runtime* runtime = Runtime::Current();
363  ClassLinker* class_linker = runtime->GetClassLinker();
364  Class* object_array_class = class_linker->FindSystemClass("[Ljava/lang/Object;");
365  Thread* self = Thread::Current();
366
367  // build an Object[] of all the DexCaches used in the source_space_
368  ObjectArray<Object>* dex_caches = ObjectArray<Object>::Alloc(self, object_array_class,
369                                                               dex_caches_.size());
370  int i = 0;
371  typedef Set::const_iterator It;  // TODO: C++0x auto
372  for (It it = dex_caches_.begin(), end = dex_caches_.end(); it != end; ++it, ++i) {
373    dex_caches->Set(i, *it);
374  }
375
376  // build an Object[] of the roots needed to restore the runtime
377  SirtRef<ObjectArray<Object> >
378      image_roots(self,
379                  ObjectArray<Object>::Alloc(self, object_array_class,
380                                             ImageHeader::kImageRootsMax));
381  image_roots->Set(ImageHeader::kResolutionMethod, runtime->GetResolutionMethod());
382  image_roots->Set(ImageHeader::kCalleeSaveMethod,
383                   runtime->GetCalleeSaveMethod(Runtime::kSaveAll));
384  image_roots->Set(ImageHeader::kRefsOnlySaveMethod,
385                   runtime->GetCalleeSaveMethod(Runtime::kRefsOnly));
386  image_roots->Set(ImageHeader::kRefsAndArgsSaveMethod,
387                   runtime->GetCalleeSaveMethod(Runtime::kRefsAndArgs));
388  image_roots->Set(ImageHeader::kOatLocation,
389                   String::AllocFromModifiedUtf8(self, oat_file_->GetLocation().c_str()));
390  image_roots->Set(ImageHeader::kDexCaches,
391                   dex_caches);
392  image_roots->Set(ImageHeader::kClassRoots,
393                   class_linker->GetClassRoots());
394  for (int i = 0; i < ImageHeader::kImageRootsMax; i++) {
395    CHECK(image_roots->Get(i) != NULL);
396  }
397  return image_roots.get();
398}
399
400void ImageWriter::CalculateNewObjectOffsets(size_t oat_loaded_size, size_t oat_data_offset) {
401  CHECK_NE(0U, oat_loaded_size);
402  Thread* self = Thread::Current();
403  SirtRef<ObjectArray<Object> > image_roots(self, CreateImageRoots());
404
405  gc::Heap* heap = Runtime::Current()->GetHeap();
406  const std::vector<gc::space::ContinuousSpace*>& spaces = heap->GetContinuousSpaces();
407  DCHECK(!spaces.empty());
408  DCHECK_EQ(0U, image_end_);
409
410  // leave space for the header, but do not write it yet, we need to
411  // know where image_roots is going to end up
412  image_end_ += RoundUp(sizeof(ImageHeader), 8);  // 64-bit-alignment
413
414  {
415    WriterMutexLock mu(self, *Locks::heap_bitmap_lock_);
416    heap->FlushAllocStack();
417    // TODO: Image spaces only?
418    // TODO: Add InOrderWalk to heap bitmap.
419    const char* old = self->StartAssertNoThreadSuspension("ImageWriter");
420    DCHECK(heap->GetLargeObjectsSpace()->GetLiveObjects()->IsEmpty());
421    // TODO: C++0x auto
422    typedef std::vector<gc::space::ContinuousSpace*>::const_iterator It;
423    for (It it = spaces.begin(), end = spaces.end(); it != end; ++it) {
424      gc::space::ContinuousSpace* space = *it;
425      space->GetLiveBitmap()->InOrderWalk(CalculateNewObjectOffsetsCallback, this);
426      DCHECK_LT(image_end_, image_->Size());
427    }
428    self->EndAssertNoThreadSuspension(old);
429  }
430
431  const byte* oat_file_begin = image_begin_ + RoundUp(image_end_, kPageSize);
432  const byte* oat_file_end = oat_file_begin + oat_loaded_size;
433  oat_data_begin_ = oat_file_begin + oat_data_offset;
434  const byte* oat_data_end = oat_data_begin_ + oat_file_->Size();
435
436  // return to write header at start of image with future location of image_roots
437  ImageHeader image_header(reinterpret_cast<uint32_t>(image_begin_),
438                           reinterpret_cast<uint32_t>(GetImageAddress(image_roots.get())),
439                           oat_file_->GetOatHeader().GetChecksum(),
440                           reinterpret_cast<uint32_t>(oat_file_begin),
441                           reinterpret_cast<uint32_t>(oat_data_begin_),
442                           reinterpret_cast<uint32_t>(oat_data_end),
443                           reinterpret_cast<uint32_t>(oat_file_end));
444  memcpy(image_->Begin(), &image_header, sizeof(image_header));
445
446  // Note that image_end_ is left at end of used space
447}
448
449void ImageWriter::CopyAndFixupObjects()
450    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
451  Thread* self = Thread::Current();
452  const char* old_cause = self->StartAssertNoThreadSuspension("ImageWriter");
453  gc::Heap* heap = Runtime::Current()->GetHeap();
454  // TODO: heap validation can't handle this fix up pass
455  heap->DisableObjectValidation();
456  // TODO: Image spaces only?
457  WriterMutexLock mu(self, *Locks::heap_bitmap_lock_);
458  heap->FlushAllocStack();
459  heap->GetLiveBitmap()->Walk(CopyAndFixupObjectsCallback, this);
460  self->EndAssertNoThreadSuspension(old_cause);
461}
462
463void ImageWriter::CopyAndFixupObjectsCallback(Object* object, void* arg) {
464  DCHECK(object != NULL);
465  DCHECK(arg != NULL);
466  const Object* obj = object;
467  ImageWriter* image_writer = reinterpret_cast<ImageWriter*>(arg);
468
469  // see GetLocalAddress for similar computation
470  size_t offset = image_writer->GetImageOffset(obj);
471  byte* dst = image_writer->image_->Begin() + offset;
472  const byte* src = reinterpret_cast<const byte*>(obj);
473  size_t n = obj->SizeOf();
474  DCHECK_LT(offset + n, image_writer->image_->Size());
475  memcpy(dst, src, n);
476  Object* copy = reinterpret_cast<Object*>(dst);
477  copy->SetField32(Object::MonitorOffset(), 0, false);  // We may have inflated the lock during compilation.
478  image_writer->FixupObject(obj, copy);
479}
480
481void ImageWriter::FixupObject(const Object* orig, Object* copy) {
482  DCHECK(orig != NULL);
483  DCHECK(copy != NULL);
484  copy->SetClass(down_cast<Class*>(GetImageAddress(orig->GetClass())));
485  // TODO: special case init of pointers to malloc data (or removal of these pointers)
486  if (orig->IsClass()) {
487    FixupClass(orig->AsClass(), down_cast<Class*>(copy));
488  } else if (orig->IsObjectArray()) {
489    FixupObjectArray(orig->AsObjectArray<Object>(), down_cast<ObjectArray<Object>*>(copy));
490  } else if (orig->IsMethod()) {
491    FixupMethod(orig->AsMethod(), down_cast<AbstractMethod*>(copy));
492  } else {
493    FixupInstanceFields(orig, copy);
494  }
495}
496
497void ImageWriter::FixupClass(const Class* orig, Class* copy) {
498  FixupInstanceFields(orig, copy);
499  FixupStaticFields(orig, copy);
500}
501
502void ImageWriter::FixupMethod(const AbstractMethod* orig, AbstractMethod* copy) {
503  FixupInstanceFields(orig, copy);
504
505  // OatWriter replaces the code_ with an offset value. Here we re-adjust to a pointer relative to
506  // oat_begin_
507
508  // The resolution method has a special trampoline to call.
509  if (UNLIKELY(orig == Runtime::Current()->GetResolutionMethod())) {
510#if defined(ART_USE_PORTABLE_COMPILER)
511    copy->SetEntryPointFromCompiledCode(GetOatAddress(portable_resolution_trampoline_offset_));
512#else
513    copy->SetEntryPointFromCompiledCode(GetOatAddress(quick_resolution_trampoline_offset_));
514#endif
515  } else {
516    // We assume all methods have code. If they don't currently then we set them to the use the
517    // resolution trampoline. Abstract methods never have code and so we need to make sure their
518    // use results in an AbstractMethodError. We use the interpreter to achieve this.
519    if (UNLIKELY(orig->IsAbstract())) {
520#if defined(ART_USE_PORTABLE_COMPILER)
521      copy->SetEntryPointFromCompiledCode(GetOatAddress(portable_to_interpreter_bridge_offset_));
522#else
523      copy->SetEntryPointFromCompiledCode(GetOatAddress(quick_to_interpreter_bridge_offset_));
524#endif
525      copy->SetEntryPointFromInterpreter(reinterpret_cast<EntryPointFromInterpreter*>
526      (GetOatAddress(interpreter_to_interpreter_bridge_offset_)));
527    } else {
528      copy->SetEntryPointFromInterpreter(reinterpret_cast<EntryPointFromInterpreter*>
529      (GetOatAddress(interpreter_to_compiled_code_bridge_offset_)));
530      // Use original code if it exists. Otherwise, set the code pointer to the resolution
531      // trampoline.
532      const byte* code = GetOatAddress(orig->GetOatCodeOffset());
533      if (code != NULL) {
534        copy->SetEntryPointFromCompiledCode(code);
535      } else {
536#if defined(ART_USE_PORTABLE_COMPILER)
537        copy->SetEntryPointFromCompiledCode(GetOatAddress(portable_resolution_trampoline_offset_));
538#else
539        copy->SetEntryPointFromCompiledCode(GetOatAddress(quick_resolution_trampoline_offset_));
540#endif
541      }
542      if (orig->IsNative()) {
543        // The native method's pointer is set to a stub to lookup via dlsym.
544        // Note this is not the code_ pointer, that is handled above.
545        copy->SetNativeMethod(GetOatAddress(jni_dlsym_lookup_offset_));
546      } else {
547        // Normal (non-abstract non-native) methods have various tables to relocate.
548        uint32_t mapping_table_off = orig->GetOatMappingTableOffset();
549        const byte* mapping_table = GetOatAddress(mapping_table_off);
550        copy->SetMappingTable(reinterpret_cast<const uint32_t*>(mapping_table));
551
552        uint32_t vmap_table_offset = orig->GetOatVmapTableOffset();
553        const byte* vmap_table = GetOatAddress(vmap_table_offset);
554        copy->SetVmapTable(reinterpret_cast<const uint16_t*>(vmap_table));
555
556        uint32_t native_gc_map_offset = orig->GetOatNativeGcMapOffset();
557        const byte* native_gc_map = GetOatAddress(native_gc_map_offset);
558        copy->SetNativeGcMap(reinterpret_cast<const uint8_t*>(native_gc_map));
559      }
560    }
561  }
562}
563
564void ImageWriter::FixupObjectArray(const ObjectArray<Object>* orig, ObjectArray<Object>* copy) {
565  for (int32_t i = 0; i < orig->GetLength(); ++i) {
566    const Object* element = orig->Get(i);
567    copy->SetPtrWithoutChecks(i, GetImageAddress(element));
568  }
569}
570
571void ImageWriter::FixupInstanceFields(const Object* orig, Object* copy) {
572  DCHECK(orig != NULL);
573  DCHECK(copy != NULL);
574  Class* klass = orig->GetClass();
575  DCHECK(klass != NULL);
576  FixupFields(orig,
577              copy,
578              klass->GetReferenceInstanceOffsets(),
579              false);
580}
581
582void ImageWriter::FixupStaticFields(const Class* orig, Class* copy) {
583  DCHECK(orig != NULL);
584  DCHECK(copy != NULL);
585  FixupFields(orig,
586              copy,
587              orig->GetReferenceStaticOffsets(),
588              true);
589}
590
591void ImageWriter::FixupFields(const Object* orig,
592                              Object* copy,
593                              uint32_t ref_offsets,
594                              bool is_static) {
595  if (ref_offsets != CLASS_WALK_SUPER) {
596    // Found a reference offset bitmap.  Fixup the specified offsets.
597    while (ref_offsets != 0) {
598      size_t right_shift = CLZ(ref_offsets);
599      MemberOffset byte_offset = CLASS_OFFSET_FROM_CLZ(right_shift);
600      const Object* ref = orig->GetFieldObject<const Object*>(byte_offset, false);
601      // Use SetFieldPtr to avoid card marking since we are writing to the image.
602      copy->SetFieldPtr(byte_offset, GetImageAddress(ref), false);
603      ref_offsets &= ~(CLASS_HIGH_BIT >> right_shift);
604    }
605  } else {
606    // There is no reference offset bitmap.  In the non-static case,
607    // walk up the class inheritance hierarchy and find reference
608    // offsets the hard way. In the static case, just consider this
609    // class.
610    for (const Class *klass = is_static ? orig->AsClass() : orig->GetClass();
611         klass != NULL;
612         klass = is_static ? NULL : klass->GetSuperClass()) {
613      size_t num_reference_fields = (is_static
614                                     ? klass->NumReferenceStaticFields()
615                                     : klass->NumReferenceInstanceFields());
616      for (size_t i = 0; i < num_reference_fields; ++i) {
617        Field* field = (is_static
618                        ? klass->GetStaticField(i)
619                        : klass->GetInstanceField(i));
620        MemberOffset field_offset = field->GetOffset();
621        const Object* ref = orig->GetFieldObject<const Object*>(field_offset, false);
622        // Use SetFieldPtr to avoid card marking since we are writing to the image.
623        copy->SetFieldPtr(field_offset, GetImageAddress(ref), false);
624      }
625    }
626  }
627  if (!is_static && orig->IsReferenceInstance()) {
628    // Fix-up referent, that isn't marked as an object field, for References.
629    Field* field = orig->GetClass()->FindInstanceField("referent", "Ljava/lang/Object;");
630    MemberOffset field_offset = field->GetOffset();
631    const Object* ref = orig->GetFieldObject<const Object*>(field_offset, false);
632    // Use SetFieldPtr to avoid card marking since we are writing to the image.
633    copy->SetFieldPtr(field_offset, GetImageAddress(ref), false);
634  }
635}
636
637static AbstractMethod* GetTargetMethod(const CompilerDriver::PatchInformation* patch)
638    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
639  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
640  DexCache* dex_cache = class_linker->FindDexCache(patch->GetDexFile());
641  AbstractMethod* method = class_linker->ResolveMethod(patch->GetDexFile(),
642                                               patch->GetTargetMethodIdx(),
643                                               dex_cache,
644                                               NULL,
645                                               NULL,
646                                               patch->GetTargetInvokeType());
647  CHECK(method != NULL)
648    << patch->GetDexFile().GetLocation() << " " << patch->GetTargetMethodIdx();
649  CHECK(!method->IsRuntimeMethod())
650    << patch->GetDexFile().GetLocation() << " " << patch->GetTargetMethodIdx();
651  CHECK(dex_cache->GetResolvedMethods()->Get(patch->GetTargetMethodIdx()) == method)
652    << patch->GetDexFile().GetLocation() << " " << patch->GetReferrerMethodIdx() << " "
653    << PrettyMethod(dex_cache->GetResolvedMethods()->Get(patch->GetTargetMethodIdx())) << " "
654    << PrettyMethod(method);
655  return method;
656}
657
658void ImageWriter::PatchOatCodeAndMethods() {
659  Thread* self = Thread::Current();
660  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
661  const char* old_cause = self->StartAssertNoThreadSuspension("ImageWriter");
662
663  typedef std::vector<const CompilerDriver::PatchInformation*> Patches;
664  const Patches& code_to_patch = compiler_driver_.GetCodeToPatch();
665  for (size_t i = 0; i < code_to_patch.size(); i++) {
666    const CompilerDriver::PatchInformation* patch = code_to_patch[i];
667    AbstractMethod* target = GetTargetMethod(patch);
668    uint32_t code = reinterpret_cast<uint32_t>(class_linker->GetOatCodeFor(target));
669    uint32_t code_base = reinterpret_cast<uint32_t>(&oat_file_->GetOatHeader());
670    uint32_t code_offset = code - code_base;
671    SetPatchLocation(patch, reinterpret_cast<uint32_t>(GetOatAddress(code_offset)));
672  }
673
674  const Patches& methods_to_patch = compiler_driver_.GetMethodsToPatch();
675  for (size_t i = 0; i < methods_to_patch.size(); i++) {
676    const CompilerDriver::PatchInformation* patch = methods_to_patch[i];
677    AbstractMethod* target = GetTargetMethod(patch);
678    SetPatchLocation(patch, reinterpret_cast<uint32_t>(GetImageAddress(target)));
679  }
680
681  // Update the image header with the new checksum after patching
682  ImageHeader* image_header = reinterpret_cast<ImageHeader*>(image_->Begin());
683  image_header->SetOatChecksum(oat_file_->GetOatHeader().GetChecksum());
684  self->EndAssertNoThreadSuspension(old_cause);
685}
686
687void ImageWriter::SetPatchLocation(const CompilerDriver::PatchInformation* patch, uint32_t value) {
688  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
689  const void* oat_code = class_linker->GetOatCodeFor(patch->GetDexFile(),
690                                                     patch->GetReferrerMethodIdx());
691  OatHeader& oat_header = const_cast<OatHeader&>(oat_file_->GetOatHeader());
692  // TODO: make this Thumb2 specific
693  uint8_t* base = reinterpret_cast<uint8_t*>(reinterpret_cast<uint32_t>(oat_code) & ~0x1);
694  uint32_t* patch_location = reinterpret_cast<uint32_t*>(base + patch->GetLiteralOffset());
695#ifndef NDEBUG
696  const DexFile::MethodId& id = patch->GetDexFile().GetMethodId(patch->GetTargetMethodIdx());
697  uint32_t expected = reinterpret_cast<uint32_t>(&id);
698  uint32_t actual = *patch_location;
699  CHECK(actual == expected || actual == value) << std::hex
700    << "actual=" << actual
701    << "expected=" << expected
702    << "value=" << value;
703#endif
704  *patch_location = value;
705  oat_header.UpdateChecksum(patch_location, sizeof(value));
706}
707
708}  // namespace art
709