class_linker.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 "class_linker.h"
18
19#include <fcntl.h>
20#include <sys/file.h>
21#include <sys/stat.h>
22#include <sys/types.h>
23#include <sys/wait.h>
24
25#include <deque>
26#include <string>
27#include <utility>
28#include <vector>
29
30#include "base/casts.h"
31#include "base/logging.h"
32#include "base/stl_util.h"
33#include "base/unix_file/fd_file.h"
34#include "class_linker-inl.h"
35#include "debugger.h"
36#include "dex_file-inl.h"
37#include "gc/accounting/card_table-inl.h"
38#include "gc/accounting/heap_bitmap.h"
39#include "gc/heap.h"
40#include "gc/space/image_space.h"
41#include "intern_table.h"
42#include "interpreter/interpreter.h"
43#include "leb128.h"
44#include "oat.h"
45#include "oat_file.h"
46#include "mirror/art_field-inl.h"
47#include "mirror/art_method-inl.h"
48#include "mirror/class.h"
49#include "mirror/class-inl.h"
50#include "mirror/class_loader.h"
51#include "mirror/dex_cache-inl.h"
52#include "mirror/iftable-inl.h"
53#include "mirror/object-inl.h"
54#include "mirror/object_array-inl.h"
55#include "mirror/proxy.h"
56#include "mirror/stack_trace_element.h"
57#include "object_utils.h"
58#include "os.h"
59#include "runtime.h"
60#include "entrypoints/entrypoint_utils.h"
61#include "ScopedLocalRef.h"
62#include "scoped_thread_state_change.h"
63#include "sirt_ref.h"
64#include "stack_indirect_reference_table.h"
65#include "thread.h"
66#include "UniquePtr.h"
67#include "utils.h"
68#include "verifier/method_verifier.h"
69#include "well_known_classes.h"
70
71namespace art {
72
73static void ThrowNoClassDefFoundError(const char* fmt, ...)
74    __attribute__((__format__(__printf__, 1, 2)))
75    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
76static void ThrowNoClassDefFoundError(const char* fmt, ...) {
77  va_list args;
78  va_start(args, fmt);
79  Thread* self = Thread::Current();
80  ThrowLocation throw_location = self->GetCurrentLocationForThrow();
81  self->ThrowNewExceptionV(throw_location, "Ljava/lang/NoClassDefFoundError;", fmt, args);
82  va_end(args);
83}
84
85static void ThrowEarlierClassFailure(mirror::Class* c)
86    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
87  // The class failed to initialize on a previous attempt, so we want to throw
88  // a NoClassDefFoundError (v2 2.17.5).  The exception to this rule is if we
89  // failed in verification, in which case v2 5.4.1 says we need to re-throw
90  // the previous error.
91  if (!Runtime::Current()->IsCompiler()) {  // Give info if this occurs at runtime.
92    LOG(INFO) << "Rejecting re-init on previously-failed class " << PrettyClass(c);
93  }
94
95  CHECK(c->IsErroneous()) << PrettyClass(c) << " " << c->GetStatus();
96  Thread* self = Thread::Current();
97  ThrowLocation throw_location = self->GetCurrentLocationForThrow();
98  if (c->GetVerifyErrorClass() != NULL) {
99    // TODO: change the verifier to store an _instance_, with a useful detail message?
100    ClassHelper ve_ch(c->GetVerifyErrorClass());
101    self->ThrowNewException(throw_location, ve_ch.GetDescriptor(), PrettyDescriptor(c).c_str());
102  } else {
103    self->ThrowNewException(throw_location, "Ljava/lang/NoClassDefFoundError;",
104                            PrettyDescriptor(c).c_str());
105  }
106}
107
108static void WrapExceptionInInitializer() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
109  Thread* self = Thread::Current();
110  JNIEnv* env = self->GetJniEnv();
111
112  ScopedLocalRef<jthrowable> cause(env, env->ExceptionOccurred());
113  CHECK(cause.get() != NULL);
114
115  env->ExceptionClear();
116  bool is_error = env->IsInstanceOf(cause.get(), WellKnownClasses::java_lang_Error);
117  env->Throw(cause.get());
118
119  // We only wrap non-Error exceptions; an Error can just be used as-is.
120  if (!is_error) {
121    ThrowLocation throw_location = self->GetCurrentLocationForThrow();
122    self->ThrowNewWrappedException(throw_location, "Ljava/lang/ExceptionInInitializerError;", NULL);
123  }
124}
125
126static size_t Hash(const char* s) {
127  // This is the java.lang.String hashcode for convenience, not interoperability.
128  size_t hash = 0;
129  for (; *s != '\0'; ++s) {
130    hash = hash * 31 + *s;
131  }
132  return hash;
133}
134
135const char* ClassLinker::class_roots_descriptors_[] = {
136  "Ljava/lang/Class;",
137  "Ljava/lang/Object;",
138  "[Ljava/lang/Class;",
139  "[Ljava/lang/Object;",
140  "Ljava/lang/String;",
141  "Ljava/lang/DexCache;",
142  "Ljava/lang/ref/Reference;",
143  "Ljava/lang/reflect/ArtField;",
144  "Ljava/lang/reflect/ArtMethod;",
145  "Ljava/lang/reflect/Proxy;",
146  "[Ljava/lang/String;",
147  "[Ljava/lang/reflect/ArtField;",
148  "[Ljava/lang/reflect/ArtMethod;",
149  "Ljava/lang/ClassLoader;",
150  "Ljava/lang/Throwable;",
151  "Ljava/lang/ClassNotFoundException;",
152  "Ljava/lang/StackTraceElement;",
153  "Z",
154  "B",
155  "C",
156  "D",
157  "F",
158  "I",
159  "J",
160  "S",
161  "V",
162  "[Z",
163  "[B",
164  "[C",
165  "[D",
166  "[F",
167  "[I",
168  "[J",
169  "[S",
170  "[Ljava/lang/StackTraceElement;",
171};
172
173ClassLinker* ClassLinker::CreateFromCompiler(const std::vector<const DexFile*>& boot_class_path,
174                                             InternTable* intern_table) {
175  CHECK_NE(boot_class_path.size(), 0U);
176  UniquePtr<ClassLinker> class_linker(new ClassLinker(intern_table));
177  class_linker->InitFromCompiler(boot_class_path);
178  return class_linker.release();
179}
180
181ClassLinker* ClassLinker::CreateFromImage(InternTable* intern_table) {
182  UniquePtr<ClassLinker> class_linker(new ClassLinker(intern_table));
183  class_linker->InitFromImage();
184  return class_linker.release();
185}
186
187ClassLinker::ClassLinker(InternTable* intern_table)
188    // dex_lock_ is recursive as it may be used in stack dumping.
189    : dex_lock_("ClassLinker dex lock", kDefaultMutexLevel),
190      dex_cache_image_class_lookup_required_(false),
191      failed_dex_cache_class_lookups_(0),
192      class_roots_(NULL),
193      array_iftable_(NULL),
194      init_done_(false),
195      dex_caches_dirty_(false),
196      class_table_dirty_(false),
197      intern_table_(intern_table),
198      portable_resolution_trampoline_(NULL),
199      quick_resolution_trampoline_(NULL) {
200  CHECK_EQ(arraysize(class_roots_descriptors_), size_t(kClassRootsMax));
201}
202
203void ClassLinker::InitFromCompiler(const std::vector<const DexFile*>& boot_class_path) {
204  VLOG(startup) << "ClassLinker::Init";
205  CHECK(Runtime::Current()->IsCompiler());
206
207  CHECK(!init_done_);
208
209  // java_lang_Class comes first, it's needed for AllocClass
210  Thread* self = Thread::Current();
211  gc::Heap* heap = Runtime::Current()->GetHeap();
212  SirtRef<mirror::Class>
213      java_lang_Class(self,
214                      down_cast<mirror::Class*>(heap->AllocObject(self, NULL,
215                                                                  sizeof(mirror::ClassClass))));
216  CHECK(java_lang_Class.get() != NULL);
217  mirror::Class::SetClassClass(java_lang_Class.get());
218  java_lang_Class->SetClass(java_lang_Class.get());
219  java_lang_Class->SetClassSize(sizeof(mirror::ClassClass));
220  // AllocClass(mirror::Class*) can now be used
221
222  // Class[] is used for reflection support.
223  SirtRef<mirror::Class> class_array_class(self, AllocClass(self, java_lang_Class.get(), sizeof(mirror::Class)));
224  class_array_class->SetComponentType(java_lang_Class.get());
225
226  // java_lang_Object comes next so that object_array_class can be created.
227  SirtRef<mirror::Class> java_lang_Object(self, AllocClass(self, java_lang_Class.get(), sizeof(mirror::Class)));
228  CHECK(java_lang_Object.get() != NULL);
229  // backfill Object as the super class of Class.
230  java_lang_Class->SetSuperClass(java_lang_Object.get());
231  java_lang_Object->SetStatus(mirror::Class::kStatusLoaded, self);
232
233  // Object[] next to hold class roots.
234  SirtRef<mirror::Class> object_array_class(self, AllocClass(self, java_lang_Class.get(), sizeof(mirror::Class)));
235  object_array_class->SetComponentType(java_lang_Object.get());
236
237  // Setup the char class to be used for char[].
238  SirtRef<mirror::Class> char_class(self, AllocClass(self, java_lang_Class.get(), sizeof(mirror::Class)));
239
240  // Setup the char[] class to be used for String.
241  SirtRef<mirror::Class> char_array_class(self, AllocClass(self, java_lang_Class.get(), sizeof(mirror::Class)));
242  char_array_class->SetComponentType(char_class.get());
243  mirror::CharArray::SetArrayClass(char_array_class.get());
244
245  // Setup String.
246  SirtRef<mirror::Class> java_lang_String(self, AllocClass(self, java_lang_Class.get(), sizeof(mirror::StringClass)));
247  mirror::String::SetClass(java_lang_String.get());
248  java_lang_String->SetObjectSize(sizeof(mirror::String));
249  java_lang_String->SetStatus(mirror::Class::kStatusResolved, self);
250
251  // Create storage for root classes, save away our work so far (requires descriptors).
252  class_roots_ = mirror::ObjectArray<mirror::Class>::Alloc(self, object_array_class.get(), kClassRootsMax);
253  CHECK(class_roots_ != NULL);
254  SetClassRoot(kJavaLangClass, java_lang_Class.get());
255  SetClassRoot(kJavaLangObject, java_lang_Object.get());
256  SetClassRoot(kClassArrayClass, class_array_class.get());
257  SetClassRoot(kObjectArrayClass, object_array_class.get());
258  SetClassRoot(kCharArrayClass, char_array_class.get());
259  SetClassRoot(kJavaLangString, java_lang_String.get());
260
261  // Setup the primitive type classes.
262  SetClassRoot(kPrimitiveBoolean, CreatePrimitiveClass(self, Primitive::kPrimBoolean));
263  SetClassRoot(kPrimitiveByte, CreatePrimitiveClass(self, Primitive::kPrimByte));
264  SetClassRoot(kPrimitiveShort, CreatePrimitiveClass(self, Primitive::kPrimShort));
265  SetClassRoot(kPrimitiveInt, CreatePrimitiveClass(self, Primitive::kPrimInt));
266  SetClassRoot(kPrimitiveLong, CreatePrimitiveClass(self, Primitive::kPrimLong));
267  SetClassRoot(kPrimitiveFloat, CreatePrimitiveClass(self, Primitive::kPrimFloat));
268  SetClassRoot(kPrimitiveDouble, CreatePrimitiveClass(self, Primitive::kPrimDouble));
269  SetClassRoot(kPrimitiveVoid, CreatePrimitiveClass(self, Primitive::kPrimVoid));
270
271  // Create array interface entries to populate once we can load system classes.
272  array_iftable_ = AllocIfTable(self, 2);
273
274  // Create int array type for AllocDexCache (done in AppendToBootClassPath).
275  SirtRef<mirror::Class> int_array_class(self, AllocClass(self, java_lang_Class.get(), sizeof(mirror::Class)));
276  int_array_class->SetComponentType(GetClassRoot(kPrimitiveInt));
277  mirror::IntArray::SetArrayClass(int_array_class.get());
278  SetClassRoot(kIntArrayClass, int_array_class.get());
279
280  // now that these are registered, we can use AllocClass() and AllocObjectArray
281
282  // Set up DexCache. This cannot be done later since AppendToBootClassPath calls AllocDexCache.
283  SirtRef<mirror::Class>
284      java_lang_DexCache(self, AllocClass(self, java_lang_Class.get(), sizeof(mirror::DexCacheClass)));
285  SetClassRoot(kJavaLangDexCache, java_lang_DexCache.get());
286  java_lang_DexCache->SetObjectSize(sizeof(mirror::DexCache));
287  java_lang_DexCache->SetStatus(mirror::Class::kStatusResolved, self);
288
289  // Constructor, Field, Method, and AbstractMethod are necessary so that FindClass can link members.
290  SirtRef<mirror::Class> java_lang_reflect_ArtField(self, AllocClass(self, java_lang_Class.get(),
291                                                                     sizeof(mirror::ArtFieldClass)));
292  CHECK(java_lang_reflect_ArtField.get() != NULL);
293  java_lang_reflect_ArtField->SetObjectSize(sizeof(mirror::ArtField));
294  SetClassRoot(kJavaLangReflectArtField, java_lang_reflect_ArtField.get());
295  java_lang_reflect_ArtField->SetStatus(mirror::Class::kStatusResolved, self);
296  mirror::ArtField::SetClass(java_lang_reflect_ArtField.get());
297
298  SirtRef<mirror::Class> java_lang_reflect_ArtMethod(self, AllocClass(self, java_lang_Class.get(),
299                                                                      sizeof(mirror::ArtMethodClass)));
300  CHECK(java_lang_reflect_ArtMethod.get() != NULL);
301  java_lang_reflect_ArtMethod->SetObjectSize(sizeof(mirror::ArtMethod));
302  SetClassRoot(kJavaLangReflectArtMethod, java_lang_reflect_ArtMethod.get());
303  java_lang_reflect_ArtMethod->SetStatus(mirror::Class::kStatusResolved, self);
304
305  mirror::ArtMethod::SetClass(java_lang_reflect_ArtMethod.get());
306
307  // Set up array classes for string, field, method
308  SirtRef<mirror::Class> object_array_string(self, AllocClass(self, java_lang_Class.get(),
309                                                              sizeof(mirror::Class)));
310  object_array_string->SetComponentType(java_lang_String.get());
311  SetClassRoot(kJavaLangStringArrayClass, object_array_string.get());
312
313  SirtRef<mirror::Class> object_array_art_method(self, AllocClass(self, java_lang_Class.get(),
314                                                                  sizeof(mirror::Class)));
315  object_array_art_method->SetComponentType(java_lang_reflect_ArtMethod.get());
316  SetClassRoot(kJavaLangReflectArtMethodArrayClass, object_array_art_method.get());
317
318  SirtRef<mirror::Class> object_array_art_field(self, AllocClass(self, java_lang_Class.get(),
319                                                                 sizeof(mirror::Class)));
320  object_array_art_field->SetComponentType(java_lang_reflect_ArtField.get());
321  SetClassRoot(kJavaLangReflectArtFieldArrayClass, object_array_art_field.get());
322
323  // Setup boot_class_path_ and register class_path now that we can use AllocObjectArray to create
324  // DexCache instances. Needs to be after String, Field, Method arrays since AllocDexCache uses
325  // these roots.
326  CHECK_NE(0U, boot_class_path.size());
327  for (size_t i = 0; i != boot_class_path.size(); ++i) {
328    const DexFile* dex_file = boot_class_path[i];
329    CHECK(dex_file != NULL);
330    AppendToBootClassPath(*dex_file);
331  }
332
333  // now we can use FindSystemClass
334
335  // run char class through InitializePrimitiveClass to finish init
336  InitializePrimitiveClass(char_class.get(), Primitive::kPrimChar);
337  SetClassRoot(kPrimitiveChar, char_class.get());  // needs descriptor
338
339  // Object, String and DexCache need to be rerun through FindSystemClass to finish init
340  java_lang_Object->SetStatus(mirror::Class::kStatusNotReady, self);
341  mirror::Class* Object_class = FindSystemClass("Ljava/lang/Object;");
342  CHECK_EQ(java_lang_Object.get(), Object_class);
343  CHECK_EQ(java_lang_Object->GetObjectSize(), sizeof(mirror::Object));
344  java_lang_String->SetStatus(mirror::Class::kStatusNotReady, self);
345  mirror::Class* String_class = FindSystemClass("Ljava/lang/String;");
346  CHECK_EQ(java_lang_String.get(), String_class);
347  CHECK_EQ(java_lang_String->GetObjectSize(), sizeof(mirror::String));
348  java_lang_DexCache->SetStatus(mirror::Class::kStatusNotReady, self);
349  mirror::Class* DexCache_class = FindSystemClass("Ljava/lang/DexCache;");
350  CHECK_EQ(java_lang_String.get(), String_class);
351  CHECK_EQ(java_lang_DexCache.get(), DexCache_class);
352  CHECK_EQ(java_lang_DexCache->GetObjectSize(), sizeof(mirror::DexCache));
353
354  // Setup the primitive array type classes - can't be done until Object has a vtable.
355  SetClassRoot(kBooleanArrayClass, FindSystemClass("[Z"));
356  mirror::BooleanArray::SetArrayClass(GetClassRoot(kBooleanArrayClass));
357
358  SetClassRoot(kByteArrayClass, FindSystemClass("[B"));
359  mirror::ByteArray::SetArrayClass(GetClassRoot(kByteArrayClass));
360
361  mirror::Class* found_char_array_class = FindSystemClass("[C");
362  CHECK_EQ(char_array_class.get(), found_char_array_class);
363
364  SetClassRoot(kShortArrayClass, FindSystemClass("[S"));
365  mirror::ShortArray::SetArrayClass(GetClassRoot(kShortArrayClass));
366
367  mirror::Class* found_int_array_class = FindSystemClass("[I");
368  CHECK_EQ(int_array_class.get(), found_int_array_class);
369
370  SetClassRoot(kLongArrayClass, FindSystemClass("[J"));
371  mirror::LongArray::SetArrayClass(GetClassRoot(kLongArrayClass));
372
373  SetClassRoot(kFloatArrayClass, FindSystemClass("[F"));
374  mirror::FloatArray::SetArrayClass(GetClassRoot(kFloatArrayClass));
375
376  SetClassRoot(kDoubleArrayClass, FindSystemClass("[D"));
377  mirror::DoubleArray::SetArrayClass(GetClassRoot(kDoubleArrayClass));
378
379  mirror::Class* found_class_array_class = FindSystemClass("[Ljava/lang/Class;");
380  CHECK_EQ(class_array_class.get(), found_class_array_class);
381
382  mirror::Class* found_object_array_class = FindSystemClass("[Ljava/lang/Object;");
383  CHECK_EQ(object_array_class.get(), found_object_array_class);
384
385  // Setup the single, global copy of "iftable".
386  mirror::Class* java_lang_Cloneable = FindSystemClass("Ljava/lang/Cloneable;");
387  CHECK(java_lang_Cloneable != NULL);
388  mirror::Class* java_io_Serializable = FindSystemClass("Ljava/io/Serializable;");
389  CHECK(java_io_Serializable != NULL);
390  // We assume that Cloneable/Serializable don't have superinterfaces -- normally we'd have to
391  // crawl up and explicitly list all of the supers as well.
392  array_iftable_->SetInterface(0, java_lang_Cloneable);
393  array_iftable_->SetInterface(1, java_io_Serializable);
394
395  // Sanity check Class[] and Object[]'s interfaces.
396  ClassHelper kh(class_array_class.get(), this);
397  CHECK_EQ(java_lang_Cloneable, kh.GetDirectInterface(0));
398  CHECK_EQ(java_io_Serializable, kh.GetDirectInterface(1));
399  kh.ChangeClass(object_array_class.get());
400  CHECK_EQ(java_lang_Cloneable, kh.GetDirectInterface(0));
401  CHECK_EQ(java_io_Serializable, kh.GetDirectInterface(1));
402  // Run Class, ArtField, and ArtMethod through FindSystemClass. This initializes their
403  // dex_cache_ fields and register them in class_table_.
404  mirror::Class* Class_class = FindSystemClass("Ljava/lang/Class;");
405  CHECK_EQ(java_lang_Class.get(), Class_class);
406
407  java_lang_reflect_ArtMethod->SetStatus(mirror::Class::kStatusNotReady, self);
408  mirror::Class* Art_method_class = FindSystemClass("Ljava/lang/reflect/ArtMethod;");
409  CHECK_EQ(java_lang_reflect_ArtMethod.get(), Art_method_class);
410
411  java_lang_reflect_ArtField->SetStatus(mirror::Class::kStatusNotReady, self);
412  mirror::Class* Art_field_class = FindSystemClass("Ljava/lang/reflect/ArtField;");
413  CHECK_EQ(java_lang_reflect_ArtField.get(), Art_field_class);
414
415  mirror::Class* String_array_class = FindSystemClass(class_roots_descriptors_[kJavaLangStringArrayClass]);
416  CHECK_EQ(object_array_string.get(), String_array_class);
417
418  mirror::Class* Art_method_array_class =
419      FindSystemClass(class_roots_descriptors_[kJavaLangReflectArtMethodArrayClass]);
420  CHECK_EQ(object_array_art_method.get(), Art_method_array_class);
421
422  mirror::Class* Art_field_array_class =
423      FindSystemClass(class_roots_descriptors_[kJavaLangReflectArtFieldArrayClass]);
424  CHECK_EQ(object_array_art_field.get(), Art_field_array_class);
425
426  // End of special init trickery, subsequent classes may be loaded via FindSystemClass.
427
428  // Create java.lang.reflect.Proxy root.
429  mirror::Class* java_lang_reflect_Proxy = FindSystemClass("Ljava/lang/reflect/Proxy;");
430  SetClassRoot(kJavaLangReflectProxy, java_lang_reflect_Proxy);
431
432  // java.lang.ref classes need to be specially flagged, but otherwise are normal classes
433  mirror::Class* java_lang_ref_Reference = FindSystemClass("Ljava/lang/ref/Reference;");
434  SetClassRoot(kJavaLangRefReference, java_lang_ref_Reference);
435  mirror::Class* java_lang_ref_FinalizerReference = FindSystemClass("Ljava/lang/ref/FinalizerReference;");
436  java_lang_ref_FinalizerReference->SetAccessFlags(
437      java_lang_ref_FinalizerReference->GetAccessFlags() |
438          kAccClassIsReference | kAccClassIsFinalizerReference);
439  mirror::Class* java_lang_ref_PhantomReference = FindSystemClass("Ljava/lang/ref/PhantomReference;");
440  java_lang_ref_PhantomReference->SetAccessFlags(
441      java_lang_ref_PhantomReference->GetAccessFlags() |
442          kAccClassIsReference | kAccClassIsPhantomReference);
443  mirror::Class* java_lang_ref_SoftReference = FindSystemClass("Ljava/lang/ref/SoftReference;");
444  java_lang_ref_SoftReference->SetAccessFlags(
445      java_lang_ref_SoftReference->GetAccessFlags() | kAccClassIsReference);
446  mirror::Class* java_lang_ref_WeakReference = FindSystemClass("Ljava/lang/ref/WeakReference;");
447  java_lang_ref_WeakReference->SetAccessFlags(
448      java_lang_ref_WeakReference->GetAccessFlags() |
449          kAccClassIsReference | kAccClassIsWeakReference);
450
451  // Setup the ClassLoader, verifying the object_size_.
452  mirror::Class* java_lang_ClassLoader = FindSystemClass("Ljava/lang/ClassLoader;");
453  CHECK_EQ(java_lang_ClassLoader->GetObjectSize(), sizeof(mirror::ClassLoader));
454  SetClassRoot(kJavaLangClassLoader, java_lang_ClassLoader);
455
456  // Set up java.lang.Throwable, java.lang.ClassNotFoundException, and
457  // java.lang.StackTraceElement as a convenience.
458  SetClassRoot(kJavaLangThrowable, FindSystemClass("Ljava/lang/Throwable;"));
459  mirror::Throwable::SetClass(GetClassRoot(kJavaLangThrowable));
460  SetClassRoot(kJavaLangClassNotFoundException, FindSystemClass("Ljava/lang/ClassNotFoundException;"));
461  SetClassRoot(kJavaLangStackTraceElement, FindSystemClass("Ljava/lang/StackTraceElement;"));
462  SetClassRoot(kJavaLangStackTraceElementArrayClass, FindSystemClass("[Ljava/lang/StackTraceElement;"));
463  mirror::StackTraceElement::SetClass(GetClassRoot(kJavaLangStackTraceElement));
464
465  FinishInit();
466
467  VLOG(startup) << "ClassLinker::InitFromCompiler exiting";
468}
469
470void ClassLinker::FinishInit() {
471  VLOG(startup) << "ClassLinker::FinishInit entering";
472
473  // Let the heap know some key offsets into java.lang.ref instances
474  // Note: we hard code the field indexes here rather than using FindInstanceField
475  // as the types of the field can't be resolved prior to the runtime being
476  // fully initialized
477  mirror::Class* java_lang_ref_Reference = GetClassRoot(kJavaLangRefReference);
478  mirror::Class* java_lang_ref_FinalizerReference =
479      FindSystemClass("Ljava/lang/ref/FinalizerReference;");
480
481  mirror::ArtField* pendingNext = java_lang_ref_Reference->GetInstanceField(0);
482  FieldHelper fh(pendingNext, this);
483  CHECK_STREQ(fh.GetName(), "pendingNext");
484  CHECK_STREQ(fh.GetTypeDescriptor(), "Ljava/lang/ref/Reference;");
485
486  mirror::ArtField* queue = java_lang_ref_Reference->GetInstanceField(1);
487  fh.ChangeField(queue);
488  CHECK_STREQ(fh.GetName(), "queue");
489  CHECK_STREQ(fh.GetTypeDescriptor(), "Ljava/lang/ref/ReferenceQueue;");
490
491  mirror::ArtField* queueNext = java_lang_ref_Reference->GetInstanceField(2);
492  fh.ChangeField(queueNext);
493  CHECK_STREQ(fh.GetName(), "queueNext");
494  CHECK_STREQ(fh.GetTypeDescriptor(), "Ljava/lang/ref/Reference;");
495
496  mirror::ArtField* referent = java_lang_ref_Reference->GetInstanceField(3);
497  fh.ChangeField(referent);
498  CHECK_STREQ(fh.GetName(), "referent");
499  CHECK_STREQ(fh.GetTypeDescriptor(), "Ljava/lang/Object;");
500
501  mirror::ArtField* zombie = java_lang_ref_FinalizerReference->GetInstanceField(2);
502  fh.ChangeField(zombie);
503  CHECK_STREQ(fh.GetName(), "zombie");
504  CHECK_STREQ(fh.GetTypeDescriptor(), "Ljava/lang/Object;");
505
506  gc::Heap* heap = Runtime::Current()->GetHeap();
507  heap->SetReferenceOffsets(referent->GetOffset(),
508                            queue->GetOffset(),
509                            queueNext->GetOffset(),
510                            pendingNext->GetOffset(),
511                            zombie->GetOffset());
512
513  // ensure all class_roots_ are initialized
514  for (size_t i = 0; i < kClassRootsMax; i++) {
515    ClassRoot class_root = static_cast<ClassRoot>(i);
516    mirror::Class* klass = GetClassRoot(class_root);
517    CHECK(klass != NULL);
518    DCHECK(klass->IsArrayClass() || klass->IsPrimitive() || klass->GetDexCache() != NULL);
519    // note SetClassRoot does additional validation.
520    // if possible add new checks there to catch errors early
521  }
522
523  CHECK(array_iftable_ != NULL);
524
525  // disable the slow paths in FindClass and CreatePrimitiveClass now
526  // that Object, Class, and Object[] are setup
527  init_done_ = true;
528
529  VLOG(startup) << "ClassLinker::FinishInit exiting";
530}
531
532void ClassLinker::RunRootClinits() {
533  Thread* self = Thread::Current();
534  for (size_t i = 0; i < ClassLinker::kClassRootsMax; ++i) {
535    mirror::Class* c = GetClassRoot(ClassRoot(i));
536    if (!c->IsArrayClass() && !c->IsPrimitive()) {
537      EnsureInitialized(GetClassRoot(ClassRoot(i)), true, true);
538      self->AssertNoPendingException();
539    }
540  }
541}
542
543bool ClassLinker::GenerateOatFile(const char* dex_filename,
544                                  int oat_fd,
545                                  const char* oat_cache_filename) {
546  Locks::mutator_lock_->AssertNotHeld(Thread::Current());  // Avoid starving GC.
547  std::string dex2oat_string(GetAndroidRoot());
548  dex2oat_string += (kIsDebugBuild ? "/bin/dex2oatd" : "/bin/dex2oat");
549  const char* dex2oat = dex2oat_string.c_str();
550
551  const char* class_path = Runtime::Current()->GetClassPathString().c_str();
552
553  gc::Heap* heap = Runtime::Current()->GetHeap();
554  std::string boot_image_option_string("--boot-image=");
555  boot_image_option_string += heap->GetImageSpace()->GetImageFilename();
556  const char* boot_image_option = boot_image_option_string.c_str();
557
558  std::string dex_file_option_string("--dex-file=");
559  dex_file_option_string += dex_filename;
560  const char* dex_file_option = dex_file_option_string.c_str();
561
562  std::string oat_fd_option_string("--oat-fd=");
563  StringAppendF(&oat_fd_option_string, "%d", oat_fd);
564  const char* oat_fd_option = oat_fd_option_string.c_str();
565
566  std::string oat_location_option_string("--oat-location=");
567  oat_location_option_string += oat_cache_filename;
568  const char* oat_location_option = oat_location_option_string.c_str();
569
570  std::string oat_compiler_filter_string("-compiler-filter:");
571  Runtime::CompilerFilter filter = Runtime::Current()->GetCompilerFilter();
572  switch (filter) {
573    case Runtime::kInterpretOnly:
574      oat_compiler_filter_string += "interpret-only";
575      break;
576    case Runtime::kSpace:
577      oat_compiler_filter_string += "space";
578      break;
579    case Runtime::kBalanced:
580      oat_compiler_filter_string += "balanced";
581      break;
582    case Runtime::kSpeed:
583      oat_compiler_filter_string += "speed";
584      break;
585    case Runtime::kEverything:
586      oat_compiler_filter_string += "everything";
587      break;
588    default:
589      LOG(FATAL) << "Unexpected case: " << filter;
590  }
591  const char* oat_compiler_filter_option = oat_compiler_filter_string.c_str();
592
593  // fork and exec dex2oat
594  pid_t pid = fork();
595  if (pid == 0) {
596    // no allocation allowed between fork and exec
597
598    // change process groups, so we don't get reaped by ProcessManager
599    setpgid(0, 0);
600
601    // gLogVerbosity.class_linker = true;
602    VLOG(class_linker) << dex2oat
603                       << " --runtime-arg -Xms64m"
604                       << " --runtime-arg -Xmx64m"
605                       << " --runtime-arg -classpath"
606                       << " --runtime-arg " << class_path
607                       << " --runtime-arg " << oat_compiler_filter_option
608#if !defined(ART_TARGET)
609                       << " --host"
610#endif
611                       << " " << boot_image_option
612                       << " " << dex_file_option
613                       << " " << oat_fd_option
614                       << " " << oat_location_option;
615
616    execl(dex2oat, dex2oat,
617          "--runtime-arg", "-Xms64m",
618          "--runtime-arg", "-Xmx64m",
619          "--runtime-arg", "-classpath",
620          "--runtime-arg", class_path,
621          "--runtime-arg", oat_compiler_filter_option,
622#if !defined(ART_TARGET)
623          "--host",
624#endif
625          boot_image_option,
626          dex_file_option,
627          oat_fd_option,
628          oat_location_option,
629          NULL);
630
631    PLOG(FATAL) << "execl(" << dex2oat << ") failed";
632    return false;
633  } else {
634    // wait for dex2oat to finish
635    int status;
636    pid_t got_pid = TEMP_FAILURE_RETRY(waitpid(pid, &status, 0));
637    if (got_pid != pid) {
638      ScopedObjectAccess soa(Thread::Current());
639      ThrowIOException("Failed to create oat file. Waitpid failed: wanted %d, got %d", pid,
640                       got_pid);
641      return false;
642    }
643    if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
644      ScopedObjectAccess soa(Thread::Current());
645      ThrowIOException("Failed to create oat file. %s failed with dex-file '%s'", dex2oat,
646                       dex_filename);
647      return false;
648    }
649  }
650  return true;
651}
652
653const OatFile* ClassLinker::RegisterOatFile(const OatFile* oat_file) {
654  WriterMutexLock mu(Thread::Current(), dex_lock_);
655  for (size_t i = 0; i < oat_files_.size(); ++i) {
656    if (UNLIKELY(oat_file->GetLocation() == oat_files_[i]->GetLocation())) {
657      VLOG(class_linker) << "Attempt to register oat file that's already registered: "
658          << oat_file->GetLocation();
659      for (size_t j = i; j < oat_files_.size(); ++j) {
660        CHECK_NE(oat_file, oat_files_[j]) << "Attempt to re-register dex file.";
661      }
662      delete oat_file;
663      return oat_files_[i];
664    }
665  }
666  VLOG(class_linker) << "Registering " << oat_file->GetLocation();
667  oat_files_.push_back(oat_file);
668  return oat_file;
669}
670
671OatFile& ClassLinker::GetImageOatFile(gc::space::ImageSpace* space) {
672  VLOG(startup) << "ClassLinker::GetImageOatFile entering";
673  OatFile* oat_file = space->ReleaseOatFile();
674  CHECK_EQ(RegisterOatFile(oat_file), oat_file);
675  VLOG(startup) << "ClassLinker::GetImageOatFile exiting";
676  return *oat_file;
677}
678
679const OatFile* ClassLinker::FindOpenedOatFileForDexFile(const DexFile& dex_file) {
680  return FindOpenedOatFileFromDexLocation(dex_file.GetLocation().c_str(),
681                                          dex_file.GetLocationChecksum());
682}
683
684const OatFile* ClassLinker::FindOpenedOatFileFromDexLocation(const char* dex_location,
685                                                             uint32_t dex_location_checksum) {
686  ReaderMutexLock mu(Thread::Current(), dex_lock_);
687  for (size_t i = 0; i < oat_files_.size(); i++) {
688    const OatFile* oat_file = oat_files_[i];
689    DCHECK(oat_file != NULL);
690    const OatFile::OatDexFile* oat_dex_file = oat_file->GetOatDexFile(dex_location,
691                                                                      &dex_location_checksum,
692                                                                      false);
693    if (oat_dex_file != NULL) {
694      return oat_file;
695    }
696  }
697  return NULL;
698}
699
700const DexFile* ClassLinker::FindDexFileInOatLocation(const char* dex_location,
701                                                     uint32_t dex_location_checksum,
702                                                     const char* oat_location,
703                                                     std::string* error_msg) {
704  UniquePtr<OatFile> oat_file(OatFile::Open(oat_location, oat_location, NULL,
705                                            !Runtime::Current()->IsCompiler(),
706                                            error_msg));
707  if (oat_file.get() == nullptr) {
708    *error_msg = StringPrintf("Failed to find existing oat file at %s: %s", oat_location,
709                              error_msg->c_str());
710    return nullptr;
711  }
712  Runtime* runtime = Runtime::Current();
713  const ImageHeader& image_header = runtime->GetHeap()->GetImageSpace()->GetImageHeader();
714  uint32_t expected_image_oat_checksum = image_header.GetOatChecksum();
715  uint32_t actual_image_oat_checksum = oat_file->GetOatHeader().GetImageFileLocationOatChecksum();
716  if (expected_image_oat_checksum != actual_image_oat_checksum) {
717    *error_msg = StringPrintf("Failed to find oat file at '%s' with expected image oat checksum of "
718                              "0x%x, found 0x%x", oat_location, expected_image_oat_checksum,
719                              actual_image_oat_checksum);
720    return nullptr;
721  }
722
723  uint32_t expected_image_oat_offset = reinterpret_cast<uint32_t>(image_header.GetOatDataBegin());
724  uint32_t actual_image_oat_offset = oat_file->GetOatHeader().GetImageFileLocationOatDataBegin();
725  if (expected_image_oat_offset != actual_image_oat_offset) {
726    *error_msg = StringPrintf("Failed to find oat file at '%s' with expected image oat offset %ud, "
727                              "found %ud", oat_location, expected_image_oat_offset,
728                              actual_image_oat_offset);
729    return nullptr;
730  }
731  // TODO: this registers the oat file now as we may use the oat_dex_file later and we want the
732  //       intern behavior of RegisterOatFile. However, if we take an early return we could remove
733  //       the oat file.
734  const OatFile* opened_oat_file = RegisterOatFile(oat_file.release());
735  const OatFile::OatDexFile* oat_dex_file = opened_oat_file->GetOatDexFile(dex_location,
736                                                                           &dex_location_checksum);
737  if (oat_dex_file == nullptr) {
738    *error_msg = StringPrintf("Failed to find oat file at '%s' containing '%s'", oat_location,
739                              dex_location);
740    return nullptr;
741  }
742  uint32_t expected_dex_checksum = dex_location_checksum;
743  uint32_t actual_dex_checksum = oat_dex_file->GetDexFileLocationChecksum();
744  if (expected_dex_checksum != actual_dex_checksum) {
745    *error_msg = StringPrintf("Failed to find oat file at '%s' with expected dex checksum of 0x%x, "
746                              "found 0x%x", oat_location, expected_dex_checksum,
747                              actual_dex_checksum);
748    return nullptr;
749  }
750  return oat_dex_file->OpenDexFile(error_msg);
751}
752
753class ScopedFlock {
754 public:
755  ScopedFlock() {}
756
757  bool Init(const char* filename, std::string* error_msg) {
758    while (true) {
759      file_.reset(OS::OpenFileWithFlags(filename, O_CREAT | O_RDWR));
760      if (file_.get() == NULL) {
761        *error_msg = StringPrintf("Failed to open file '%s'", filename);
762        return false;
763      }
764      int flock_result = TEMP_FAILURE_RETRY(flock(file_->Fd(), LOCK_EX));
765      if (flock_result != 0) {
766        *error_msg = StringPrintf("Failed to lock file '%s': %s", filename, strerror(errno));
767        return false;
768      }
769      struct stat fstat_stat;
770      int fstat_result = TEMP_FAILURE_RETRY(fstat(file_->Fd(), &fstat_stat));
771      if (fstat_result != 0) {
772        *error_msg = StringPrintf("Failed to fstat file '%s': %s", filename, strerror(errno));
773        return false;
774      }
775      struct stat stat_stat;
776      int stat_result = TEMP_FAILURE_RETRY(stat(filename, &stat_stat));
777      if (stat_result != 0) {
778        PLOG(WARNING) << "Failed to stat, will retry: " << filename;
779        // ENOENT can happen if someone racing with us unlinks the file we created so just retry.
780        continue;
781      }
782      if (fstat_stat.st_dev != stat_stat.st_dev || fstat_stat.st_ino != stat_stat.st_ino) {
783        LOG(WARNING) << "File changed while locking, will retry: " << filename;
784        continue;
785      }
786      return true;
787    }
788  }
789
790  File& GetFile() {
791    return *file_;
792  }
793
794  ~ScopedFlock() {
795    if (file_.get() != NULL) {
796      int flock_result = TEMP_FAILURE_RETRY(flock(file_->Fd(), LOCK_UN));
797      CHECK_EQ(0, flock_result);
798    }
799  }
800
801 private:
802  UniquePtr<File> file_;
803
804  DISALLOW_COPY_AND_ASSIGN(ScopedFlock);
805};
806
807const DexFile* ClassLinker::FindOrCreateOatFileForDexLocation(const char* dex_location,
808                                                              uint32_t dex_location_checksum,
809                                                              const char* oat_location,
810                                                              std::string* error_msg) {
811  // We play a locking game here so that if two different processes
812  // race to generate (or worse, one tries to open a partial generated
813  // file) we will be okay. This is actually common with apps that use
814  // DexClassLoader to work around the dex method reference limit and
815  // that have a background service running in a separate process.
816  ScopedFlock scoped_flock;
817  if (!scoped_flock.Init(oat_location, error_msg)) {
818    return nullptr;
819  }
820
821  // Check if we already have an up-to-date output file
822  const DexFile* dex_file = FindDexFileInOatLocation(dex_location, dex_location_checksum,
823                                                     oat_location, error_msg);
824  if (dex_file != nullptr) {
825    return dex_file;
826  }
827  VLOG(class_linker) << "Failed to find dex file '" << dex_location << "' in oat location '"
828      << oat_location << "': " << *error_msg;
829  error_msg->clear();
830
831  // Generate the output oat file for the dex file
832  VLOG(class_linker) << "Generating oat file " << oat_location << " for " << dex_location;
833  if (!GenerateOatFile(dex_location, scoped_flock.GetFile().Fd(), oat_location)) {
834    CHECK(Thread::Current()->IsExceptionPending());
835    return nullptr;
836  }
837  const OatFile* oat_file = OatFile::Open(oat_location, oat_location, NULL,
838                                          !Runtime::Current()->IsCompiler(),
839                                          error_msg);
840  if (oat_file == nullptr) {
841    *error_msg = StringPrintf("Failed to open generated oat file '%s': %s",
842                              oat_location, error_msg->c_str());
843    return nullptr;
844  }
845  oat_file = RegisterOatFile(oat_file);
846  const OatFile::OatDexFile* oat_dex_file = oat_file->GetOatDexFile(dex_location,
847                                                                    &dex_location_checksum);
848  if (oat_dex_file == nullptr) {
849    *error_msg = StringPrintf("Failed to find dex file '%s' (checksum 0x%x) in generated out file "
850                              "'%s'", dex_location, dex_location_checksum, oat_location);
851    return nullptr;
852  }
853  const DexFile* result = oat_dex_file->OpenDexFile(error_msg);
854  CHECK(result != nullptr) << *error_msg;
855  CHECK_EQ(dex_location_checksum, result->GetLocationChecksum())
856          << "dex_location=" << dex_location << " oat_location=" << oat_location << std::hex
857          << " dex_location_checksum=" << dex_location_checksum
858          << " DexFile::GetLocationChecksum()=" << result->GetLocationChecksum();
859  return result;
860}
861
862bool ClassLinker::VerifyOatFileChecksums(const OatFile* oat_file,
863                                         const char* dex_location,
864                                         uint32_t dex_location_checksum,
865                                         std::string* error_msg) {
866  Runtime* runtime = Runtime::Current();
867  const ImageHeader& image_header = runtime->GetHeap()->GetImageSpace()->GetImageHeader();
868  uint32_t image_oat_checksum = image_header.GetOatChecksum();
869  uint32_t image_oat_data_begin = reinterpret_cast<uint32_t>(image_header.GetOatDataBegin());
870  bool image_check = ((oat_file->GetOatHeader().GetImageFileLocationOatChecksum() == image_oat_checksum)
871                      && (oat_file->GetOatHeader().GetImageFileLocationOatDataBegin() == image_oat_data_begin));
872
873  const OatFile::OatDexFile* oat_dex_file = oat_file->GetOatDexFile(dex_location, &dex_location_checksum);
874  if (oat_dex_file == NULL) {
875    *error_msg = StringPrintf("oat file '%s' does not contain contents for '%s' with checksum 0x%x",
876                              oat_file->GetLocation().c_str(), dex_location, dex_location_checksum);
877    std::vector<const OatFile::OatDexFile*> oat_dex_files = oat_file->GetOatDexFiles();
878    for (size_t i = 0; i < oat_dex_files.size(); i++) {
879      const OatFile::OatDexFile* oat_dex_file = oat_dex_files[i];
880      *error_msg  += StringPrintf("\noat file '%s' contains contents for '%s'",
881                                  oat_file->GetLocation().c_str(),
882                                  oat_dex_file->GetDexFileLocation().c_str());
883    }
884    return false;
885  }
886  bool dex_check = dex_location_checksum == oat_dex_file->GetDexFileLocationChecksum();
887
888  if (image_check && dex_check) {
889    return true;
890  }
891
892  if (!image_check) {
893    ScopedObjectAccess soa(Thread::Current());
894    mirror::String* oat_location = image_header.GetImageRoot(ImageHeader::kOatLocation)->AsString();
895    std::string image_file(oat_location->ToModifiedUtf8());
896    *error_msg = StringPrintf("oat file '%s' mismatch (0x%x, %d) with '%s' (0x%x, %d)",
897                              oat_file->GetLocation().c_str(),
898                              oat_file->GetOatHeader().GetImageFileLocationOatChecksum(),
899                              oat_file->GetOatHeader().GetImageFileLocationOatDataBegin(),
900                              image_file.c_str(), image_oat_checksum, image_oat_data_begin);
901  }
902  if (!dex_check) {
903    *error_msg = StringPrintf("oat file '%s' mismatch (0x%x) with '%s' (0x%x)",
904                              oat_file->GetLocation().c_str(),
905                              oat_dex_file->GetDexFileLocationChecksum(),
906                              dex_location, dex_location_checksum);
907  }
908  return false;
909}
910
911const DexFile* ClassLinker::VerifyAndOpenDexFileFromOatFile(const std::string& oat_file_location,
912                                                            const char* dex_location,
913                                                            std::string* error_msg,
914                                                            bool* open_failed) {
915  UniquePtr<const OatFile> oat_file(FindOatFileFromOatLocation(oat_file_location, error_msg));
916  if (oat_file.get() == nullptr) {
917    *open_failed = true;
918    return nullptr;
919  }
920  *open_failed = false;
921  uint32_t dex_location_checksum;
922  if (!DexFile::GetChecksum(dex_location, &dex_location_checksum, error_msg)) {
923    // If no classes.dex found in dex_location, it has been stripped or is corrupt, assume oat is
924    // up-to-date. This is the common case in user builds for jar's and apk's in the /system
925    // directory.
926    const OatFile* opened_oat_file = oat_file.release();
927    opened_oat_file = RegisterOatFile(opened_oat_file);
928    const OatFile::OatDexFile* oat_dex_file = opened_oat_file->GetOatDexFile(dex_location, NULL);
929    if (oat_dex_file == nullptr) {
930      *error_msg = StringPrintf("Dex checksum mismatch for location '%s' and failed to find oat "
931                                "dex file '%s': %s", oat_file_location.c_str(), dex_location,
932                                error_msg->c_str());
933      return nullptr;
934    }
935    return oat_dex_file->OpenDexFile(error_msg);
936  }
937
938  bool verified = VerifyOatFileChecksums(oat_file.get(), dex_location, dex_location_checksum,
939                                         error_msg);
940  if (!verified) {
941    return nullptr;
942  }
943  const OatFile* opened_oat_file = oat_file.release();
944  opened_oat_file = RegisterOatFile(opened_oat_file);
945  return opened_oat_file->GetOatDexFile(dex_location,
946                                        &dex_location_checksum)->OpenDexFile(error_msg);
947}
948
949const DexFile* ClassLinker::FindDexFileInOatFileFromDexLocation(const char* dex_location,
950                                                                uint32_t dex_location_checksum,
951                                                                std::string* error_msg) {
952  const OatFile* open_oat_file = FindOpenedOatFileFromDexLocation(dex_location,
953                                                                  dex_location_checksum);
954  if (open_oat_file != nullptr) {
955    const OatFile::OatDexFile* oat_dex_file = open_oat_file->GetOatDexFile(dex_location,
956                                                                           &dex_location_checksum);
957    return oat_dex_file->OpenDexFile(error_msg);
958  }
959
960  // Look for an existing file next to dex. for example, for
961  // /foo/bar/baz.jar, look for /foo/bar/baz.odex.
962  std::string odex_filename(OatFile::DexFilenameToOdexFilename(dex_location));
963  bool open_failed;
964  const DexFile* dex_file = VerifyAndOpenDexFileFromOatFile(odex_filename, dex_location,
965                                                            error_msg, &open_failed);
966  if (dex_file != nullptr) {
967    return dex_file;
968  }
969  std::string cache_error_msg;
970  std::string cache_location(GetDalvikCacheFilenameOrDie(dex_location));
971  dex_file = VerifyAndOpenDexFileFromOatFile(cache_location, dex_location, &cache_error_msg,
972                                             &open_failed);
973  if (dex_file != nullptr) {
974    return dex_file;
975  }
976  if (!open_failed && TEMP_FAILURE_RETRY(unlink(cache_location.c_str())) != 0) {
977    PLOG(FATAL) << "Failed to remove obsolete oat file from " << cache_location;
978  }
979  VLOG(class_linker) << "Failed to open oat file from " << odex_filename
980      << " (error '" << *error_msg << "') or " << cache_location
981      << " (error '" << cache_error_msg << "').";
982
983  // Try to generate oat file if it wasn't found or was obsolete.
984  error_msg->clear();
985  return FindOrCreateOatFileForDexLocation(dex_location, dex_location_checksum,
986                                           cache_location.c_str(), error_msg);
987}
988
989const OatFile* ClassLinker::FindOpenedOatFileFromOatLocation(const std::string& oat_location) {
990  ReaderMutexLock mu(Thread::Current(), dex_lock_);
991  for (size_t i = 0; i < oat_files_.size(); i++) {
992    const OatFile* oat_file = oat_files_[i];
993    DCHECK(oat_file != nullptr);
994    if (oat_file->GetLocation() == oat_location) {
995      return oat_file;
996    }
997  }
998  return nullptr;
999}
1000
1001const OatFile* ClassLinker::FindOatFileFromOatLocation(const std::string& oat_location,
1002                                                       std::string* error_msg) {
1003  const OatFile* oat_file = FindOpenedOatFileFromOatLocation(oat_location);
1004  if (oat_file != nullptr) {
1005    return oat_file;
1006  }
1007
1008  oat_file = OatFile::Open(oat_location, oat_location, NULL, !Runtime::Current()->IsCompiler(),
1009                           error_msg);
1010  if (oat_file == NULL) {
1011    return NULL;
1012  }
1013  return oat_file;
1014}
1015
1016static void InitFromImageInterpretOnlyCallback(mirror::Object* obj, void* arg)
1017    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1018  ClassLinker* class_linker = reinterpret_cast<ClassLinker*>(arg);
1019
1020  DCHECK(obj != NULL);
1021  DCHECK(class_linker != NULL);
1022
1023  if (obj->IsArtMethod()) {
1024    mirror::ArtMethod* method = obj->AsArtMethod();
1025    if (!method->IsNative()) {
1026      method->SetEntryPointFromInterpreter(interpreter::artInterpreterToInterpreterBridge);
1027      if (method != Runtime::Current()->GetResolutionMethod()) {
1028        method->SetEntryPointFromCompiledCode(GetCompiledCodeToInterpreterBridge());
1029      }
1030    }
1031  }
1032}
1033
1034void ClassLinker::InitFromImage() {
1035  VLOG(startup) << "ClassLinker::InitFromImage entering";
1036  CHECK(!init_done_);
1037
1038  gc::Heap* heap = Runtime::Current()->GetHeap();
1039  gc::space::ImageSpace* space = heap->GetImageSpace();
1040  dex_cache_image_class_lookup_required_ = true;
1041  CHECK(space != NULL);
1042  OatFile& oat_file = GetImageOatFile(space);
1043  CHECK_EQ(oat_file.GetOatHeader().GetImageFileLocationOatChecksum(), 0U);
1044  CHECK_EQ(oat_file.GetOatHeader().GetImageFileLocationOatDataBegin(), 0U);
1045  CHECK(oat_file.GetOatHeader().GetImageFileLocation().empty());
1046  portable_resolution_trampoline_ = oat_file.GetOatHeader().GetPortableResolutionTrampoline();
1047  quick_resolution_trampoline_ = oat_file.GetOatHeader().GetQuickResolutionTrampoline();
1048  mirror::Object* dex_caches_object = space->GetImageHeader().GetImageRoot(ImageHeader::kDexCaches);
1049  mirror::ObjectArray<mirror::DexCache>* dex_caches =
1050      dex_caches_object->AsObjectArray<mirror::DexCache>();
1051
1052  mirror::ObjectArray<mirror::Class>* class_roots =
1053      space->GetImageHeader().GetImageRoot(ImageHeader::kClassRoots)->AsObjectArray<mirror::Class>();
1054  class_roots_ = class_roots;
1055
1056  // Special case of setting up the String class early so that we can test arbitrary objects
1057  // as being Strings or not
1058  mirror::String::SetClass(GetClassRoot(kJavaLangString));
1059
1060  CHECK_EQ(oat_file.GetOatHeader().GetDexFileCount(),
1061           static_cast<uint32_t>(dex_caches->GetLength()));
1062  Thread* self = Thread::Current();
1063  for (int32_t i = 0; i < dex_caches->GetLength(); i++) {
1064    SirtRef<mirror::DexCache> dex_cache(self, dex_caches->Get(i));
1065    const std::string& dex_file_location(dex_cache->GetLocation()->ToModifiedUtf8());
1066    const OatFile::OatDexFile* oat_dex_file = oat_file.GetOatDexFile(dex_file_location.c_str(),
1067                                                                     nullptr);
1068    CHECK(oat_dex_file != NULL) << oat_file.GetLocation() << " " << dex_file_location;
1069    std::string error_msg;
1070    const DexFile* dex_file = oat_dex_file->OpenDexFile(&error_msg);
1071    if (dex_file == NULL) {
1072      LOG(FATAL) << "Failed to open dex file " << dex_file_location
1073                 << " from within oat file " << oat_file.GetLocation()
1074                 << " error '" << error_msg << "'";
1075    }
1076
1077    CHECK_EQ(dex_file->GetLocationChecksum(), oat_dex_file->GetDexFileLocationChecksum());
1078
1079    AppendToBootClassPath(*dex_file, dex_cache);
1080  }
1081
1082  // Set classes on AbstractMethod early so that IsMethod tests can be performed during the live
1083  // bitmap walk.
1084  mirror::ArtMethod::SetClass(GetClassRoot(kJavaLangReflectArtMethod));
1085
1086  // Set entry point to interpreter if in InterpretOnly mode.
1087  if (Runtime::Current()->GetInstrumentation()->InterpretOnly()) {
1088    ReaderMutexLock mu(self, *Locks::heap_bitmap_lock_);
1089    heap->FlushAllocStack();
1090    heap->GetLiveBitmap()->Walk(InitFromImageInterpretOnlyCallback, this);
1091  }
1092
1093  // reinit class_roots_
1094  mirror::Class::SetClassClass(class_roots->Get(kJavaLangClass));
1095  class_roots_ = class_roots;
1096
1097  // reinit array_iftable_ from any array class instance, they should be ==
1098  array_iftable_ = GetClassRoot(kObjectArrayClass)->GetIfTable();
1099  DCHECK(array_iftable_ == GetClassRoot(kBooleanArrayClass)->GetIfTable());
1100  // String class root was set above
1101  mirror::ArtField::SetClass(GetClassRoot(kJavaLangReflectArtField));
1102  mirror::BooleanArray::SetArrayClass(GetClassRoot(kBooleanArrayClass));
1103  mirror::ByteArray::SetArrayClass(GetClassRoot(kByteArrayClass));
1104  mirror::CharArray::SetArrayClass(GetClassRoot(kCharArrayClass));
1105  mirror::DoubleArray::SetArrayClass(GetClassRoot(kDoubleArrayClass));
1106  mirror::FloatArray::SetArrayClass(GetClassRoot(kFloatArrayClass));
1107  mirror::IntArray::SetArrayClass(GetClassRoot(kIntArrayClass));
1108  mirror::LongArray::SetArrayClass(GetClassRoot(kLongArrayClass));
1109  mirror::ShortArray::SetArrayClass(GetClassRoot(kShortArrayClass));
1110  mirror::Throwable::SetClass(GetClassRoot(kJavaLangThrowable));
1111  mirror::StackTraceElement::SetClass(GetClassRoot(kJavaLangStackTraceElement));
1112
1113  FinishInit();
1114
1115  VLOG(startup) << "ClassLinker::InitFromImage exiting";
1116}
1117
1118// Keep in sync with InitCallback. Anything we visit, we need to
1119// reinit references to when reinitializing a ClassLinker from a
1120// mapped image.
1121void ClassLinker::VisitRoots(RootVisitor* visitor, void* arg, bool only_dirty, bool clean_dirty) {
1122  class_roots_ = down_cast<mirror::ObjectArray<mirror::Class>*>(visitor(class_roots_, arg));
1123  Thread* self = Thread::Current();
1124  {
1125    ReaderMutexLock mu(self, dex_lock_);
1126    if (!only_dirty || dex_caches_dirty_) {
1127      for (mirror::DexCache*& dex_cache : dex_caches_) {
1128        dex_cache = down_cast<mirror::DexCache*>(visitor(dex_cache, arg));
1129        DCHECK(dex_cache != nullptr);
1130      }
1131      if (clean_dirty) {
1132        dex_caches_dirty_ = false;
1133      }
1134    }
1135  }
1136
1137  {
1138    ReaderMutexLock mu(self, *Locks::classlinker_classes_lock_);
1139    if (!only_dirty || class_table_dirty_) {
1140      for (std::pair<const size_t, mirror::Class*>& it : class_table_) {
1141        it.second = down_cast<mirror::Class*>(visitor(it.second, arg));
1142        DCHECK(it.second != nullptr);
1143      }
1144      if (clean_dirty) {
1145        class_table_dirty_ = false;
1146      }
1147    }
1148
1149    // We deliberately ignore the class roots in the image since we
1150    // handle image roots by using the MS/CMS rescanning of dirty cards.
1151  }
1152
1153  array_iftable_ = reinterpret_cast<mirror::IfTable*>(visitor(array_iftable_, arg));
1154  DCHECK(array_iftable_ != nullptr);
1155}
1156
1157void ClassLinker::VisitClasses(ClassVisitor* visitor, void* arg) {
1158  if (dex_cache_image_class_lookup_required_) {
1159    MoveImageClassesToClassTable();
1160  }
1161  ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_);
1162  for (const std::pair<size_t, mirror::Class*>& it : class_table_) {
1163    if (!visitor(it.second, arg)) {
1164      return;
1165    }
1166  }
1167}
1168
1169static bool GetClassesVisitor(mirror::Class* c, void* arg) {
1170  std::set<mirror::Class*>* classes = reinterpret_cast<std::set<mirror::Class*>*>(arg);
1171  classes->insert(c);
1172  return true;
1173}
1174
1175void ClassLinker::VisitClassesWithoutClassesLock(ClassVisitor* visitor, void* arg) {
1176  std::set<mirror::Class*> classes;
1177  VisitClasses(GetClassesVisitor, &classes);
1178  for (mirror::Class* klass : classes) {
1179    if (!visitor(klass, arg)) {
1180      return;
1181    }
1182  }
1183}
1184
1185
1186ClassLinker::~ClassLinker() {
1187  mirror::Class::ResetClass();
1188  mirror::String::ResetClass();
1189  mirror::ArtField::ResetClass();
1190  mirror::ArtMethod::ResetClass();
1191  mirror::BooleanArray::ResetArrayClass();
1192  mirror::ByteArray::ResetArrayClass();
1193  mirror::CharArray::ResetArrayClass();
1194  mirror::DoubleArray::ResetArrayClass();
1195  mirror::FloatArray::ResetArrayClass();
1196  mirror::IntArray::ResetArrayClass();
1197  mirror::LongArray::ResetArrayClass();
1198  mirror::ShortArray::ResetArrayClass();
1199  mirror::Throwable::ResetClass();
1200  mirror::StackTraceElement::ResetClass();
1201  STLDeleteElements(&boot_class_path_);
1202  STLDeleteElements(&oat_files_);
1203}
1204
1205mirror::DexCache* ClassLinker::AllocDexCache(Thread* self, const DexFile& dex_file) {
1206  gc::Heap* heap = Runtime::Current()->GetHeap();
1207  mirror::Class* dex_cache_class = GetClassRoot(kJavaLangDexCache);
1208  SirtRef<mirror::DexCache> dex_cache(self,
1209                              down_cast<mirror::DexCache*>(heap->AllocObject(self, dex_cache_class,
1210                                                                dex_cache_class->GetObjectSize())));
1211  if (dex_cache.get() == NULL) {
1212    return NULL;
1213  }
1214  SirtRef<mirror::String>
1215      location(self, intern_table_->InternStrong(dex_file.GetLocation().c_str()));
1216  if (location.get() == NULL) {
1217    return NULL;
1218  }
1219  SirtRef<mirror::ObjectArray<mirror::String> >
1220      strings(self, AllocStringArray(self, dex_file.NumStringIds()));
1221  if (strings.get() == NULL) {
1222    return NULL;
1223  }
1224  SirtRef<mirror::ObjectArray<mirror::Class> >
1225      types(self, AllocClassArray(self, dex_file.NumTypeIds()));
1226  if (types.get() == NULL) {
1227    return NULL;
1228  }
1229  SirtRef<mirror::ObjectArray<mirror::ArtMethod> >
1230      methods(self, AllocArtMethodArray(self, dex_file.NumMethodIds()));
1231  if (methods.get() == NULL) {
1232    return NULL;
1233  }
1234  SirtRef<mirror::ObjectArray<mirror::ArtField> >
1235      fields(self, AllocArtFieldArray(self, dex_file.NumFieldIds()));
1236  if (fields.get() == NULL) {
1237    return NULL;
1238  }
1239  SirtRef<mirror::ObjectArray<mirror::StaticStorageBase> >
1240      initialized_static_storage(self,
1241                          AllocObjectArray<mirror::StaticStorageBase>(self, dex_file.NumTypeIds()));
1242  if (initialized_static_storage.get() == NULL) {
1243    return NULL;
1244  }
1245
1246  dex_cache->Init(&dex_file,
1247                  location.get(),
1248                  strings.get(),
1249                  types.get(),
1250                  methods.get(),
1251                  fields.get(),
1252                  initialized_static_storage.get());
1253  return dex_cache.get();
1254}
1255
1256mirror::Class* ClassLinker::AllocClass(Thread* self, mirror::Class* java_lang_Class,
1257                                       size_t class_size) {
1258  DCHECK_GE(class_size, sizeof(mirror::Class));
1259  gc::Heap* heap = Runtime::Current()->GetHeap();
1260  mirror::Object* k = heap->AllocObject(self, java_lang_Class, class_size);
1261  if (UNLIKELY(k == NULL)) {
1262    CHECK(self->IsExceptionPending());  // OOME.
1263    return NULL;
1264  }
1265  mirror::Class* klass = k->AsClass();
1266  klass->SetPrimitiveType(Primitive::kPrimNot);  // Default to not being primitive.
1267  klass->SetClassSize(class_size);
1268  klass->SetDexClassDefIndex(DexFile::kDexNoIndex16);  // Default to no valid class def index.
1269  klass->SetDexTypeIndex(DexFile::kDexNoIndex16);  // Default to no valid type index.
1270  return klass;
1271}
1272
1273mirror::Class* ClassLinker::AllocClass(Thread* self, size_t class_size) {
1274  return AllocClass(self, GetClassRoot(kJavaLangClass), class_size);
1275}
1276
1277mirror::ArtField* ClassLinker::AllocArtField(Thread* self) {
1278  return down_cast<mirror::ArtField*>(GetClassRoot(kJavaLangReflectArtField)->AllocObject(self));
1279}
1280
1281mirror::ArtMethod* ClassLinker::AllocArtMethod(Thread* self) {
1282  return down_cast<mirror::ArtMethod*>(GetClassRoot(kJavaLangReflectArtMethod)->AllocObject(self));
1283}
1284
1285mirror::ObjectArray<mirror::StackTraceElement>* ClassLinker::AllocStackTraceElementArray(Thread* self,
1286                                                                                         size_t length) {
1287  return mirror::ObjectArray<mirror::StackTraceElement>::Alloc(self,
1288                                                               GetClassRoot(kJavaLangStackTraceElementArrayClass),
1289                                                               length);
1290}
1291
1292static mirror::Class* EnsureResolved(Thread* self, mirror::Class* klass)
1293    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1294  DCHECK(klass != NULL);
1295  // Wait for the class if it has not already been linked.
1296  if (!klass->IsResolved() && !klass->IsErroneous()) {
1297    ObjectLock lock(self, klass);
1298    // Check for circular dependencies between classes.
1299    if (!klass->IsResolved() && klass->GetClinitThreadId() == self->GetTid()) {
1300      ThrowClassCircularityError(klass);
1301      klass->SetStatus(mirror::Class::kStatusError, self);
1302      return NULL;
1303    }
1304    // Wait for the pending initialization to complete.
1305    while (!klass->IsResolved() && !klass->IsErroneous()) {
1306      lock.WaitIgnoringInterrupts();
1307    }
1308  }
1309  if (klass->IsErroneous()) {
1310    ThrowEarlierClassFailure(klass);
1311    return NULL;
1312  }
1313  // Return the loaded class.  No exceptions should be pending.
1314  CHECK(klass->IsResolved()) << PrettyClass(klass);
1315  self->AssertNoPendingException();
1316  return klass;
1317}
1318
1319bool ClassLinker::IsInBootClassPath(const char* descriptor) {
1320  DexFile::ClassPathEntry pair = DexFile::FindInClassPath(descriptor, boot_class_path_);
1321  return pair.second != NULL;
1322}
1323
1324mirror::Class* ClassLinker::FindSystemClass(const char* descriptor) {
1325  return FindClass(descriptor, NULL);
1326}
1327
1328mirror::Class* ClassLinker::FindClass(const char* descriptor, mirror::ClassLoader* class_loader) {
1329  DCHECK_NE(*descriptor, '\0') << "descriptor is empty string";
1330  Thread* self = Thread::Current();
1331  DCHECK(self != NULL);
1332  self->AssertNoPendingException();
1333  if (descriptor[1] == '\0') {
1334    // only the descriptors of primitive types should be 1 character long, also avoid class lookup
1335    // for primitive classes that aren't backed by dex files.
1336    return FindPrimitiveClass(descriptor[0]);
1337  }
1338  // Find the class in the loaded classes table.
1339  mirror::Class* klass = LookupClass(descriptor, class_loader);
1340  if (klass != NULL) {
1341    return EnsureResolved(self, klass);
1342  }
1343  // Class is not yet loaded.
1344  if (descriptor[0] == '[') {
1345    return CreateArrayClass(descriptor, class_loader);
1346
1347  } else if (class_loader == NULL) {
1348    DexFile::ClassPathEntry pair = DexFile::FindInClassPath(descriptor, boot_class_path_);
1349    if (pair.second != NULL) {
1350      return DefineClass(descriptor, NULL, *pair.first, *pair.second);
1351    }
1352
1353  } else if (Runtime::Current()->UseCompileTimeClassPath()) {
1354    // First try the boot class path, we check the descriptor first to avoid an unnecessary
1355    // throw of a NoClassDefFoundError.
1356    if (IsInBootClassPath(descriptor)) {
1357      mirror::Class* system_class = FindSystemClass(descriptor);
1358      CHECK(system_class != NULL);
1359      return system_class;
1360    }
1361    // Next try the compile time class path.
1362    const std::vector<const DexFile*>* class_path;
1363    {
1364      ScopedObjectAccessUnchecked soa(self);
1365      ScopedLocalRef<jobject> jclass_loader(soa.Env(), soa.AddLocalReference<jobject>(class_loader));
1366      class_path = &Runtime::Current()->GetCompileTimeClassPath(jclass_loader.get());
1367    }
1368
1369    DexFile::ClassPathEntry pair = DexFile::FindInClassPath(descriptor, *class_path);
1370    if (pair.second != NULL) {
1371      return DefineClass(descriptor, class_loader, *pair.first, *pair.second);
1372    }
1373
1374  } else {
1375    ScopedObjectAccessUnchecked soa(self->GetJniEnv());
1376    ScopedLocalRef<jobject> class_loader_object(soa.Env(),
1377                                                soa.AddLocalReference<jobject>(class_loader));
1378    std::string class_name_string(DescriptorToDot(descriptor));
1379    ScopedLocalRef<jobject> result(soa.Env(), NULL);
1380    {
1381      ScopedThreadStateChange tsc(self, kNative);
1382      ScopedLocalRef<jobject> class_name_object(soa.Env(),
1383                                                soa.Env()->NewStringUTF(class_name_string.c_str()));
1384      if (class_name_object.get() == NULL) {
1385        return NULL;
1386      }
1387      CHECK(class_loader_object.get() != NULL);
1388      result.reset(soa.Env()->CallObjectMethod(class_loader_object.get(),
1389                                               WellKnownClasses::java_lang_ClassLoader_loadClass,
1390                                               class_name_object.get()));
1391    }
1392    if (soa.Self()->IsExceptionPending()) {
1393      // If the ClassLoader threw, pass that exception up.
1394      return NULL;
1395    } else if (result.get() == NULL) {
1396      // broken loader - throw NPE to be compatible with Dalvik
1397      ThrowNullPointerException(NULL, StringPrintf("ClassLoader.loadClass returned null for %s",
1398                                                   class_name_string.c_str()).c_str());
1399      return NULL;
1400    } else {
1401      // success, return mirror::Class*
1402      return soa.Decode<mirror::Class*>(result.get());
1403    }
1404  }
1405
1406  ThrowNoClassDefFoundError("Class %s not found", PrintableString(descriptor).c_str());
1407  return NULL;
1408}
1409
1410mirror::Class* ClassLinker::DefineClass(const char* descriptor,
1411                                        mirror::ClassLoader* class_loader,
1412                                        const DexFile& dex_file,
1413                                        const DexFile::ClassDef& dex_class_def) {
1414  Thread* self = Thread::Current();
1415  SirtRef<mirror::Class> klass(self, NULL);
1416  // Load the class from the dex file.
1417  if (UNLIKELY(!init_done_)) {
1418    // finish up init of hand crafted class_roots_
1419    if (strcmp(descriptor, "Ljava/lang/Object;") == 0) {
1420      klass.reset(GetClassRoot(kJavaLangObject));
1421    } else if (strcmp(descriptor, "Ljava/lang/Class;") == 0) {
1422      klass.reset(GetClassRoot(kJavaLangClass));
1423    } else if (strcmp(descriptor, "Ljava/lang/String;") == 0) {
1424      klass.reset(GetClassRoot(kJavaLangString));
1425    } else if (strcmp(descriptor, "Ljava/lang/DexCache;") == 0) {
1426      klass.reset(GetClassRoot(kJavaLangDexCache));
1427    } else if (strcmp(descriptor, "Ljava/lang/reflect/ArtField;") == 0) {
1428      klass.reset(GetClassRoot(kJavaLangReflectArtField));
1429    } else if (strcmp(descriptor, "Ljava/lang/reflect/ArtMethod;") == 0) {
1430      klass.reset(GetClassRoot(kJavaLangReflectArtMethod));
1431    } else {
1432      klass.reset(AllocClass(self, SizeOfClass(dex_file, dex_class_def)));
1433    }
1434  } else {
1435    klass.reset(AllocClass(self, SizeOfClass(dex_file, dex_class_def)));
1436  }
1437  if (UNLIKELY(klass.get() == NULL)) {
1438    CHECK(self->IsExceptionPending());  // Expect an OOME.
1439    return NULL;
1440  }
1441  klass->SetDexCache(FindDexCache(dex_file));
1442  LoadClass(dex_file, dex_class_def, klass, class_loader);
1443  // Check for a pending exception during load
1444  if (self->IsExceptionPending()) {
1445    klass->SetStatus(mirror::Class::kStatusError, self);
1446    return NULL;
1447  }
1448  ObjectLock lock(self, klass.get());
1449  klass->SetClinitThreadId(self->GetTid());
1450  {
1451    // Add the newly loaded class to the loaded classes table.
1452    mirror::Class* existing = InsertClass(descriptor, klass.get(), Hash(descriptor));
1453    if (existing != NULL) {
1454      // We failed to insert because we raced with another thread. Calling EnsureResolved may cause
1455      // this thread to block.
1456      return EnsureResolved(self, existing);
1457    }
1458  }
1459  // Finish loading (if necessary) by finding parents
1460  CHECK(!klass->IsLoaded());
1461  if (!LoadSuperAndInterfaces(klass, dex_file)) {
1462    // Loading failed.
1463    klass->SetStatus(mirror::Class::kStatusError, self);
1464    return NULL;
1465  }
1466  CHECK(klass->IsLoaded());
1467  // Link the class (if necessary)
1468  CHECK(!klass->IsResolved());
1469  if (!LinkClass(klass, NULL, self)) {
1470    // Linking failed.
1471    klass->SetStatus(mirror::Class::kStatusError, self);
1472    return NULL;
1473  }
1474  CHECK(klass->IsResolved());
1475
1476  /*
1477   * We send CLASS_PREPARE events to the debugger from here.  The
1478   * definition of "preparation" is creating the static fields for a
1479   * class and initializing them to the standard default values, but not
1480   * executing any code (that comes later, during "initialization").
1481   *
1482   * We did the static preparation in LinkClass.
1483   *
1484   * The class has been prepared and resolved but possibly not yet verified
1485   * at this point.
1486   */
1487  Dbg::PostClassPrepare(klass.get());
1488
1489  return klass.get();
1490}
1491
1492// Precomputes size that will be needed for Class, matching LinkStaticFields
1493size_t ClassLinker::SizeOfClass(const DexFile& dex_file,
1494                                const DexFile::ClassDef& dex_class_def) {
1495  const byte* class_data = dex_file.GetClassData(dex_class_def);
1496  size_t num_ref = 0;
1497  size_t num_32 = 0;
1498  size_t num_64 = 0;
1499  if (class_data != NULL) {
1500    for (ClassDataItemIterator it(dex_file, class_data); it.HasNextStaticField(); it.Next()) {
1501      const DexFile::FieldId& field_id = dex_file.GetFieldId(it.GetMemberIndex());
1502      const char* descriptor = dex_file.GetFieldTypeDescriptor(field_id);
1503      char c = descriptor[0];
1504      if (c == 'L' || c == '[') {
1505        num_ref++;
1506      } else if (c == 'J' || c == 'D') {
1507        num_64++;
1508      } else {
1509        num_32++;
1510      }
1511    }
1512  }
1513  // start with generic class data
1514  size_t size = sizeof(mirror::Class);
1515  // follow with reference fields which must be contiguous at start
1516  size += (num_ref * sizeof(uint32_t));
1517  // if there are 64-bit fields to add, make sure they are aligned
1518  if (num_64 != 0 && size != RoundUp(size, 8)) {  // for 64-bit alignment
1519    if (num_32 != 0) {
1520      // use an available 32-bit field for padding
1521      num_32--;
1522    }
1523    size += sizeof(uint32_t);  // either way, we are adding a word
1524    DCHECK_EQ(size, RoundUp(size, 8));
1525  }
1526  // tack on any 64-bit fields now that alignment is assured
1527  size += (num_64 * sizeof(uint64_t));
1528  // tack on any remaining 32-bit fields
1529  size += (num_32 * sizeof(uint32_t));
1530  return size;
1531}
1532
1533const OatFile::OatClass* ClassLinker::GetOatClass(const DexFile& dex_file, uint16_t class_def_idx) {
1534  DCHECK_NE(class_def_idx, DexFile::kDexNoIndex16);
1535  const OatFile* oat_file = FindOpenedOatFileForDexFile(dex_file);
1536  CHECK(oat_file != NULL) << dex_file.GetLocation();
1537  uint dex_location_checksum = dex_file.GetLocationChecksum();
1538  const OatFile::OatDexFile* oat_dex_file = oat_file->GetOatDexFile(dex_file.GetLocation().c_str(),
1539                                                                    &dex_location_checksum);
1540  CHECK(oat_dex_file != NULL) << dex_file.GetLocation();
1541  const OatFile::OatClass* oat_class = oat_dex_file->GetOatClass(class_def_idx);
1542  CHECK(oat_class != NULL) << dex_file.GetLocation() << " " << class_def_idx;
1543  return oat_class;
1544}
1545
1546static uint32_t GetOatMethodIndexFromMethodIndex(const DexFile& dex_file, uint16_t class_def_idx,
1547                                                 uint32_t method_idx) {
1548  const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_idx);
1549  const byte* class_data = dex_file.GetClassData(class_def);
1550  CHECK(class_data != NULL);
1551  ClassDataItemIterator it(dex_file, class_data);
1552  // Skip fields
1553  while (it.HasNextStaticField()) {
1554    it.Next();
1555  }
1556  while (it.HasNextInstanceField()) {
1557    it.Next();
1558  }
1559  // Process methods
1560  size_t class_def_method_index = 0;
1561  while (it.HasNextDirectMethod()) {
1562    if (it.GetMemberIndex() == method_idx) {
1563      return class_def_method_index;
1564    }
1565    class_def_method_index++;
1566    it.Next();
1567  }
1568  while (it.HasNextVirtualMethod()) {
1569    if (it.GetMemberIndex() == method_idx) {
1570      return class_def_method_index;
1571    }
1572    class_def_method_index++;
1573    it.Next();
1574  }
1575  DCHECK(!it.HasNext());
1576  LOG(FATAL) << "Failed to find method index " << method_idx << " in " << dex_file.GetLocation();
1577  return 0;
1578}
1579
1580const OatFile::OatMethod ClassLinker::GetOatMethodFor(const mirror::ArtMethod* method) {
1581  // Although we overwrite the trampoline of non-static methods, we may get here via the resolution
1582  // method for direct methods (or virtual methods made direct).
1583  mirror::Class* declaring_class = method->GetDeclaringClass();
1584  size_t oat_method_index;
1585  if (method->IsStatic() || method->IsDirect()) {
1586    // Simple case where the oat method index was stashed at load time.
1587    oat_method_index = method->GetMethodIndex();
1588  } else {
1589    // We're invoking a virtual method directly (thanks to sharpening), compute the oat_method_index
1590    // by search for its position in the declared virtual methods.
1591    oat_method_index = declaring_class->NumDirectMethods();
1592    size_t end = declaring_class->NumVirtualMethods();
1593    bool found = false;
1594    for (size_t i = 0; i < end; i++) {
1595      if (declaring_class->GetVirtualMethod(i) == method) {
1596        found = true;
1597        break;
1598      }
1599      oat_method_index++;
1600    }
1601    CHECK(found) << "Didn't find oat method index for virtual method: " << PrettyMethod(method);
1602  }
1603  UniquePtr<const OatFile::OatClass>
1604      oat_class(GetOatClass(*declaring_class->GetDexCache()->GetDexFile(),
1605                            declaring_class->GetDexClassDefIndex()));
1606  CHECK(oat_class.get() != NULL);
1607  DCHECK_EQ(oat_method_index,
1608            GetOatMethodIndexFromMethodIndex(*declaring_class->GetDexCache()->GetDexFile(),
1609                                             method->GetDeclaringClass()->GetDexClassDefIndex(),
1610                                             method->GetDexMethodIndex()));
1611
1612  return oat_class->GetOatMethod(oat_method_index);
1613}
1614
1615// Special case to get oat code without overwriting a trampoline.
1616const void* ClassLinker::GetOatCodeFor(const mirror::ArtMethod* method) {
1617  CHECK(!method->IsAbstract()) << PrettyMethod(method);
1618  if (method->IsProxyMethod()) {
1619#if !defined(ART_USE_PORTABLE_COMPILER)
1620    return reinterpret_cast<void*>(art_quick_proxy_invoke_handler);
1621#else
1622    return reinterpret_cast<void*>(art_portable_proxy_invoke_handler);
1623#endif
1624  }
1625  const void* result = GetOatMethodFor(method).GetCode();
1626  if (result == NULL) {
1627    // No code? You must mean to go into the interpreter.
1628    result = GetCompiledCodeToInterpreterBridge();
1629  }
1630  return result;
1631}
1632
1633const void* ClassLinker::GetOatCodeFor(const DexFile& dex_file, uint16_t class_def_idx,
1634                                       uint32_t method_idx) {
1635  UniquePtr<const OatFile::OatClass> oat_class(GetOatClass(dex_file, class_def_idx));
1636  CHECK(oat_class.get() != nullptr);
1637  uint32_t oat_method_idx = GetOatMethodIndexFromMethodIndex(dex_file, class_def_idx, method_idx);
1638  return oat_class->GetOatMethod(oat_method_idx).GetCode();
1639}
1640
1641// Returns true if the method must run with interpreter, false otherwise.
1642static bool NeedsInterpreter(const mirror::ArtMethod* method, const void* code) {
1643  if (code == NULL) {
1644    // No code: need interpreter.
1645    return true;
1646  }
1647#ifdef ART_SEA_IR_MODE
1648  ScopedObjectAccess soa(Thread::Current());
1649  if (std::string::npos != PrettyMethod(method).find("fibonacci")) {
1650    LOG(INFO) << "Found " << PrettyMethod(method);
1651    return false;
1652  }
1653#endif
1654  // If interpreter mode is enabled, every method (except native and proxy) must
1655  // be run with interpreter.
1656  return Runtime::Current()->GetInstrumentation()->InterpretOnly() &&
1657         !method->IsNative() && !method->IsProxyMethod();
1658}
1659
1660void ClassLinker::FixupStaticTrampolines(mirror::Class* klass) {
1661  if (klass->NumDirectMethods() == 0) {
1662    return;  // No direct methods => no static methods.
1663  }
1664  Runtime* runtime = Runtime::Current();
1665  if (!runtime->IsStarted() || runtime->UseCompileTimeClassPath()) {
1666    return;  // OAT file unavailable.
1667  }
1668  ClassHelper kh(klass);
1669  const DexFile& dex_file = kh.GetDexFile();
1670  const DexFile::ClassDef* dex_class_def = kh.GetClassDef();
1671  CHECK(dex_class_def != nullptr);
1672  const byte* class_data = dex_file.GetClassData(*dex_class_def);
1673  // There should always be class data if there were direct methods.
1674  CHECK(class_data != nullptr) << PrettyDescriptor(klass);
1675  UniquePtr<const OatFile::OatClass> oat_class(GetOatClass(dex_file, klass->GetDexClassDefIndex()));
1676  CHECK(oat_class.get() != nullptr);
1677  ClassDataItemIterator it(dex_file, class_data);
1678  // Skip fields
1679  while (it.HasNextStaticField()) {
1680    it.Next();
1681  }
1682  while (it.HasNextInstanceField()) {
1683    it.Next();
1684  }
1685  // Link the code of methods skipped by LinkCode.
1686  for (size_t method_index = 0; it.HasNextDirectMethod(); ++method_index, it.Next()) {
1687    mirror::ArtMethod* method = klass->GetDirectMethod(method_index);
1688    if (!method->IsStatic()) {
1689      // Only update static methods.
1690      continue;
1691    }
1692    const void* code = oat_class->GetOatMethod(method_index).GetCode();
1693    const bool enter_interpreter = NeedsInterpreter(method, code);
1694    if (enter_interpreter) {
1695      // Use interpreter entry point.
1696      code = GetCompiledCodeToInterpreterBridge();
1697    }
1698    runtime->GetInstrumentation()->UpdateMethodsCode(method, code);
1699  }
1700  // Ignore virtual methods on the iterator.
1701}
1702
1703static void LinkCode(SirtRef<mirror::ArtMethod>& method, const OatFile::OatClass* oat_class,
1704                     uint32_t method_index)
1705    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
1706  // Method shouldn't have already been linked.
1707  DCHECK(method->GetEntryPointFromCompiledCode() == NULL);
1708  // Every kind of method should at least get an invoke stub from the oat_method.
1709  // non-abstract methods also get their code pointers.
1710  const OatFile::OatMethod oat_method = oat_class->GetOatMethod(method_index);
1711  oat_method.LinkMethod(method.get());
1712
1713  // Install entry point from interpreter.
1714  Runtime* runtime = Runtime::Current();
1715  bool enter_interpreter = NeedsInterpreter(method.get(), method->GetEntryPointFromCompiledCode());
1716  if (enter_interpreter) {
1717    method->SetEntryPointFromInterpreter(interpreter::artInterpreterToInterpreterBridge);
1718  } else {
1719    method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge);
1720  }
1721
1722  if (method->IsAbstract()) {
1723    method->SetEntryPointFromCompiledCode(GetCompiledCodeToInterpreterBridge());
1724    return;
1725  }
1726
1727  if (method->IsStatic() && !method->IsConstructor()) {
1728    // For static methods excluding the class initializer, install the trampoline.
1729    // It will be replaced by the proper entry point by ClassLinker::FixupStaticTrampolines
1730    // after initializing class (see ClassLinker::InitializeClass method).
1731    method->SetEntryPointFromCompiledCode(GetResolutionTrampoline(runtime->GetClassLinker()));
1732  } else if (enter_interpreter) {
1733    // Set entry point from compiled code if there's no code or in interpreter only mode.
1734    method->SetEntryPointFromCompiledCode(GetCompiledCodeToInterpreterBridge());
1735  }
1736
1737  if (method->IsNative()) {
1738    // Unregistering restores the dlsym lookup stub.
1739    method->UnregisterNative(Thread::Current());
1740  }
1741
1742  // Allow instrumentation its chance to hijack code.
1743  runtime->GetInstrumentation()->UpdateMethodsCode(method.get(),
1744                                                   method->GetEntryPointFromCompiledCode());
1745}
1746
1747void ClassLinker::LoadClass(const DexFile& dex_file,
1748                            const DexFile::ClassDef& dex_class_def,
1749                            SirtRef<mirror::Class>& klass,
1750                            mirror::ClassLoader* class_loader) {
1751  CHECK(klass.get() != NULL);
1752  CHECK(klass->GetDexCache() != NULL);
1753  CHECK_EQ(mirror::Class::kStatusNotReady, klass->GetStatus());
1754  const char* descriptor = dex_file.GetClassDescriptor(dex_class_def);
1755  CHECK(descriptor != NULL);
1756
1757  klass->SetClass(GetClassRoot(kJavaLangClass));
1758  uint32_t access_flags = dex_class_def.access_flags_;
1759  // Make sure that none of our runtime-only flags are set.
1760  CHECK_EQ(access_flags & ~kAccJavaFlagsMask, 0U);
1761  klass->SetAccessFlags(access_flags);
1762  klass->SetClassLoader(class_loader);
1763  DCHECK_EQ(klass->GetPrimitiveType(), Primitive::kPrimNot);
1764  klass->SetStatus(mirror::Class::kStatusIdx, NULL);
1765
1766  klass->SetDexClassDefIndex(dex_file.GetIndexForClassDef(dex_class_def));
1767  klass->SetDexTypeIndex(dex_class_def.class_idx_);
1768
1769  // Load fields fields.
1770  const byte* class_data = dex_file.GetClassData(dex_class_def);
1771  if (class_data == NULL) {
1772    return;  // no fields or methods - for example a marker interface
1773  }
1774  ClassDataItemIterator it(dex_file, class_data);
1775  Thread* self = Thread::Current();
1776  if (it.NumStaticFields() != 0) {
1777    mirror::ObjectArray<mirror::ArtField>* statics = AllocArtFieldArray(self, it.NumStaticFields());
1778    if (UNLIKELY(statics == NULL)) {
1779      CHECK(self->IsExceptionPending());  // OOME.
1780      return;
1781    }
1782    klass->SetSFields(statics);
1783  }
1784  if (it.NumInstanceFields() != 0) {
1785    mirror::ObjectArray<mirror::ArtField>* fields =
1786        AllocArtFieldArray(self, it.NumInstanceFields());
1787    if (UNLIKELY(fields == NULL)) {
1788      CHECK(self->IsExceptionPending());  // OOME.
1789      return;
1790    }
1791    klass->SetIFields(fields);
1792  }
1793  for (size_t i = 0; it.HasNextStaticField(); i++, it.Next()) {
1794    SirtRef<mirror::ArtField> sfield(self, AllocArtField(self));
1795    if (UNLIKELY(sfield.get() == NULL)) {
1796      CHECK(self->IsExceptionPending());  // OOME.
1797      return;
1798    }
1799    klass->SetStaticField(i, sfield.get());
1800    LoadField(dex_file, it, klass, sfield);
1801  }
1802  for (size_t i = 0; it.HasNextInstanceField(); i++, it.Next()) {
1803    SirtRef<mirror::ArtField> ifield(self, AllocArtField(self));
1804    if (UNLIKELY(ifield.get() == NULL)) {
1805      CHECK(self->IsExceptionPending());  // OOME.
1806      return;
1807    }
1808    klass->SetInstanceField(i, ifield.get());
1809    LoadField(dex_file, it, klass, ifield);
1810  }
1811
1812  UniquePtr<const OatFile::OatClass> oat_class;
1813  if (Runtime::Current()->IsStarted() && !Runtime::Current()->UseCompileTimeClassPath()) {
1814    oat_class.reset(GetOatClass(dex_file, klass->GetDexClassDefIndex()));
1815  }
1816
1817  // Load methods.
1818  if (it.NumDirectMethods() != 0) {
1819    // TODO: append direct methods to class object
1820    mirror::ObjectArray<mirror::ArtMethod>* directs =
1821         AllocArtMethodArray(self, it.NumDirectMethods());
1822    if (UNLIKELY(directs == NULL)) {
1823      CHECK(self->IsExceptionPending());  // OOME.
1824      return;
1825    }
1826    klass->SetDirectMethods(directs);
1827  }
1828  if (it.NumVirtualMethods() != 0) {
1829    // TODO: append direct methods to class object
1830    mirror::ObjectArray<mirror::ArtMethod>* virtuals =
1831        AllocArtMethodArray(self, it.NumVirtualMethods());
1832    if (UNLIKELY(virtuals == NULL)) {
1833      CHECK(self->IsExceptionPending());  // OOME.
1834      return;
1835    }
1836    klass->SetVirtualMethods(virtuals);
1837  }
1838  size_t class_def_method_index = 0;
1839  for (size_t i = 0; it.HasNextDirectMethod(); i++, it.Next()) {
1840    SirtRef<mirror::ArtMethod> method(self, LoadMethod(self, dex_file, it, klass));
1841    if (UNLIKELY(method.get() == NULL)) {
1842      CHECK(self->IsExceptionPending());  // OOME.
1843      return;
1844    }
1845    klass->SetDirectMethod(i, method.get());
1846    if (oat_class.get() != NULL) {
1847      LinkCode(method, oat_class.get(), class_def_method_index);
1848    }
1849    method->SetMethodIndex(class_def_method_index);
1850    class_def_method_index++;
1851  }
1852  for (size_t i = 0; it.HasNextVirtualMethod(); i++, it.Next()) {
1853    SirtRef<mirror::ArtMethod> method(self, LoadMethod(self, dex_file, it, klass));
1854    if (UNLIKELY(method.get() == NULL)) {
1855      CHECK(self->IsExceptionPending());  // OOME.
1856      return;
1857    }
1858    klass->SetVirtualMethod(i, method.get());
1859    DCHECK_EQ(class_def_method_index, it.NumDirectMethods() + i);
1860    if (oat_class.get() != NULL) {
1861      LinkCode(method, oat_class.get(), class_def_method_index);
1862    }
1863    class_def_method_index++;
1864  }
1865  DCHECK(!it.HasNext());
1866}
1867
1868void ClassLinker::LoadField(const DexFile& /*dex_file*/, const ClassDataItemIterator& it,
1869                            SirtRef<mirror::Class>& klass, SirtRef<mirror::ArtField>& dst) {
1870  uint32_t field_idx = it.GetMemberIndex();
1871  dst->SetDexFieldIndex(field_idx);
1872  dst->SetDeclaringClass(klass.get());
1873  dst->SetAccessFlags(it.GetMemberAccessFlags());
1874}
1875
1876mirror::ArtMethod* ClassLinker::LoadMethod(Thread* self, const DexFile& dex_file,
1877                                           const ClassDataItemIterator& it,
1878                                           SirtRef<mirror::Class>& klass) {
1879  uint32_t dex_method_idx = it.GetMemberIndex();
1880  const DexFile::MethodId& method_id = dex_file.GetMethodId(dex_method_idx);
1881  const char* method_name = dex_file.StringDataByIdx(method_id.name_idx_);
1882
1883  mirror::ArtMethod* dst = AllocArtMethod(self);
1884  if (UNLIKELY(dst == NULL)) {
1885    CHECK(self->IsExceptionPending());  // OOME.
1886    return NULL;
1887  }
1888  DCHECK(dst->IsArtMethod()) << PrettyDescriptor(dst->GetClass());
1889
1890  const char* old_cause = self->StartAssertNoThreadSuspension("LoadMethod");
1891  dst->SetDexMethodIndex(dex_method_idx);
1892  dst->SetDeclaringClass(klass.get());
1893  dst->SetCodeItemOffset(it.GetMethodCodeItemOffset());
1894
1895  dst->SetDexCacheStrings(klass->GetDexCache()->GetStrings());
1896  dst->SetDexCacheResolvedMethods(klass->GetDexCache()->GetResolvedMethods());
1897  dst->SetDexCacheResolvedTypes(klass->GetDexCache()->GetResolvedTypes());
1898  dst->SetDexCacheInitializedStaticStorage(klass->GetDexCache()->GetInitializedStaticStorage());
1899
1900  uint32_t access_flags = it.GetMemberAccessFlags();
1901
1902  if (UNLIKELY(strcmp("finalize", method_name) == 0)) {
1903    // Set finalizable flag on declaring class.
1904    if (strcmp("V", dex_file.GetShorty(method_id.proto_idx_)) == 0) {
1905      // Void return type.
1906      if (klass->GetClassLoader() != NULL) {  // All non-boot finalizer methods are flagged
1907        klass->SetFinalizable();
1908      } else {
1909        ClassHelper kh(klass.get());
1910        const char* klass_descriptor = kh.GetDescriptor();
1911        // The Enum class declares a "final" finalize() method to prevent subclasses from
1912        // introducing a finalizer. We don't want to set the finalizable flag for Enum or its
1913        // subclasses, so we exclude it here.
1914        // We also want to avoid setting the flag on Object, where we know that finalize() is
1915        // empty.
1916        if ((strcmp("Ljava/lang/Object;", klass_descriptor) != 0) &&
1917            (strcmp("Ljava/lang/Enum;", klass_descriptor) != 0)) {
1918          klass->SetFinalizable();
1919        }
1920      }
1921    }
1922  } else if (method_name[0] == '<') {
1923    // Fix broken access flags for initializers. Bug 11157540.
1924    bool is_init = (strcmp("<init>", method_name) == 0);
1925    bool is_clinit = !is_init && (strcmp("<clinit>", method_name) == 0);
1926    if (UNLIKELY(!is_init && !is_clinit)) {
1927      LOG(WARNING) << "Unexpected '<' at start of method name " << method_name;
1928    } else {
1929      if (UNLIKELY((access_flags & kAccConstructor) == 0)) {
1930        LOG(WARNING) << method_name << " didn't have expected constructor access flag in class "
1931            << PrettyDescriptor(klass.get()) << " in dex file " << dex_file.GetLocation();
1932        access_flags |= kAccConstructor;
1933      }
1934    }
1935  }
1936  dst->SetAccessFlags(access_flags);
1937
1938  self->EndAssertNoThreadSuspension(old_cause);
1939  return dst;
1940}
1941
1942void ClassLinker::AppendToBootClassPath(const DexFile& dex_file) {
1943  Thread* self = Thread::Current();
1944  SirtRef<mirror::DexCache> dex_cache(self, AllocDexCache(self, dex_file));
1945  CHECK(dex_cache.get() != NULL) << "Failed to allocate dex cache for " << dex_file.GetLocation();
1946  AppendToBootClassPath(dex_file, dex_cache);
1947}
1948
1949void ClassLinker::AppendToBootClassPath(const DexFile& dex_file, SirtRef<mirror::DexCache>& dex_cache) {
1950  CHECK(dex_cache.get() != NULL) << dex_file.GetLocation();
1951  boot_class_path_.push_back(&dex_file);
1952  RegisterDexFile(dex_file, dex_cache);
1953}
1954
1955bool ClassLinker::IsDexFileRegisteredLocked(const DexFile& dex_file) const {
1956  dex_lock_.AssertSharedHeld(Thread::Current());
1957  for (size_t i = 0; i != dex_caches_.size(); ++i) {
1958    if (dex_caches_[i]->GetDexFile() == &dex_file) {
1959      return true;
1960    }
1961  }
1962  return false;
1963}
1964
1965bool ClassLinker::IsDexFileRegistered(const DexFile& dex_file) const {
1966  ReaderMutexLock mu(Thread::Current(), dex_lock_);
1967  return IsDexFileRegisteredLocked(dex_file);
1968}
1969
1970void ClassLinker::RegisterDexFileLocked(const DexFile& dex_file, SirtRef<mirror::DexCache>& dex_cache) {
1971  dex_lock_.AssertExclusiveHeld(Thread::Current());
1972  CHECK(dex_cache.get() != NULL) << dex_file.GetLocation();
1973  CHECK(dex_cache->GetLocation()->Equals(dex_file.GetLocation()))
1974      << dex_cache->GetLocation()->ToModifiedUtf8() << " " << dex_file.GetLocation();
1975  dex_caches_.push_back(dex_cache.get());
1976  dex_cache->SetDexFile(&dex_file);
1977  dex_caches_dirty_ = true;
1978}
1979
1980void ClassLinker::RegisterDexFile(const DexFile& dex_file) {
1981  Thread* self = Thread::Current();
1982  {
1983    ReaderMutexLock mu(self, dex_lock_);
1984    if (IsDexFileRegisteredLocked(dex_file)) {
1985      return;
1986    }
1987  }
1988  // Don't alloc while holding the lock, since allocation may need to
1989  // suspend all threads and another thread may need the dex_lock_ to
1990  // get to a suspend point.
1991  SirtRef<mirror::DexCache> dex_cache(self, AllocDexCache(self, dex_file));
1992  CHECK(dex_cache.get() != NULL) << "Failed to allocate dex cache for " << dex_file.GetLocation();
1993  {
1994    WriterMutexLock mu(self, dex_lock_);
1995    if (IsDexFileRegisteredLocked(dex_file)) {
1996      return;
1997    }
1998    RegisterDexFileLocked(dex_file, dex_cache);
1999  }
2000}
2001
2002void ClassLinker::RegisterDexFile(const DexFile& dex_file, SirtRef<mirror::DexCache>& dex_cache) {
2003  WriterMutexLock mu(Thread::Current(), dex_lock_);
2004  RegisterDexFileLocked(dex_file, dex_cache);
2005}
2006
2007mirror::DexCache* ClassLinker::FindDexCache(const DexFile& dex_file) const {
2008  ReaderMutexLock mu(Thread::Current(), dex_lock_);
2009  // Search assuming unique-ness of dex file.
2010  for (size_t i = 0; i != dex_caches_.size(); ++i) {
2011    mirror::DexCache* dex_cache = dex_caches_[i];
2012    if (dex_cache->GetDexFile() == &dex_file) {
2013      return dex_cache;
2014    }
2015  }
2016  // Search matching by location name.
2017  std::string location(dex_file.GetLocation());
2018  for (size_t i = 0; i != dex_caches_.size(); ++i) {
2019    mirror::DexCache* dex_cache = dex_caches_[i];
2020    if (dex_cache->GetDexFile()->GetLocation() == location) {
2021      return dex_cache;
2022    }
2023  }
2024  // Failure, dump diagnostic and abort.
2025  for (size_t i = 0; i != dex_caches_.size(); ++i) {
2026    mirror::DexCache* dex_cache = dex_caches_[i];
2027    LOG(ERROR) << "Registered dex file " << i << " = " << dex_cache->GetDexFile()->GetLocation();
2028  }
2029  LOG(FATAL) << "Failed to find DexCache for DexFile " << location;
2030  return NULL;
2031}
2032
2033void ClassLinker::FixupDexCaches(mirror::ArtMethod* resolution_method) const {
2034  ReaderMutexLock mu(Thread::Current(), dex_lock_);
2035  for (size_t i = 0; i != dex_caches_.size(); ++i) {
2036    dex_caches_[i]->Fixup(resolution_method);
2037  }
2038}
2039
2040mirror::Class* ClassLinker::CreatePrimitiveClass(Thread* self, Primitive::Type type) {
2041  mirror::Class* klass = AllocClass(self, sizeof(mirror::Class));
2042  if (UNLIKELY(klass == NULL)) {
2043    return NULL;
2044  }
2045  return InitializePrimitiveClass(klass, type);
2046}
2047
2048mirror::Class* ClassLinker::InitializePrimitiveClass(mirror::Class* primitive_class, Primitive::Type type) {
2049  CHECK(primitive_class != NULL);
2050  // Must hold lock on object when initializing.
2051  Thread* self = Thread::Current();
2052  ObjectLock lock(self, primitive_class);
2053  primitive_class->SetAccessFlags(kAccPublic | kAccFinal | kAccAbstract);
2054  primitive_class->SetPrimitiveType(type);
2055  primitive_class->SetStatus(mirror::Class::kStatusInitialized, self);
2056  const char* descriptor = Primitive::Descriptor(type);
2057  mirror::Class* existing = InsertClass(descriptor, primitive_class, Hash(descriptor));
2058  CHECK(existing == NULL) << "InitPrimitiveClass(" << type << ") failed";
2059  return primitive_class;
2060}
2061
2062// Create an array class (i.e. the class object for the array, not the
2063// array itself).  "descriptor" looks like "[C" or "[[[[B" or
2064// "[Ljava/lang/String;".
2065//
2066// If "descriptor" refers to an array of primitives, look up the
2067// primitive type's internally-generated class object.
2068//
2069// "class_loader" is the class loader of the class that's referring to
2070// us.  It's used to ensure that we're looking for the element type in
2071// the right context.  It does NOT become the class loader for the
2072// array class; that always comes from the base element class.
2073//
2074// Returns NULL with an exception raised on failure.
2075mirror::Class* ClassLinker::CreateArrayClass(const char* descriptor,
2076                                             mirror::ClassLoader* class_loader) {
2077  // Identify the underlying component type
2078  CHECK_EQ('[', descriptor[0]);
2079  mirror::Class* component_type = FindClass(descriptor + 1, class_loader);
2080  if (component_type == NULL) {
2081    DCHECK(Thread::Current()->IsExceptionPending());
2082    return NULL;
2083  }
2084
2085  // See if the component type is already loaded.  Array classes are
2086  // always associated with the class loader of their underlying
2087  // element type -- an array of Strings goes with the loader for
2088  // java/lang/String -- so we need to look for it there.  (The
2089  // caller should have checked for the existence of the class
2090  // before calling here, but they did so with *their* class loader,
2091  // not the component type's loader.)
2092  //
2093  // If we find it, the caller adds "loader" to the class' initiating
2094  // loader list, which should prevent us from going through this again.
2095  //
2096  // This call is unnecessary if "loader" and "component_type->GetClassLoader()"
2097  // are the same, because our caller (FindClass) just did the
2098  // lookup.  (Even if we get this wrong we still have correct behavior,
2099  // because we effectively do this lookup again when we add the new
2100  // class to the hash table --- necessary because of possible races with
2101  // other threads.)
2102  if (class_loader != component_type->GetClassLoader()) {
2103    mirror::Class* new_class = LookupClass(descriptor, component_type->GetClassLoader());
2104    if (new_class != NULL) {
2105      return new_class;
2106    }
2107  }
2108
2109  // Fill out the fields in the Class.
2110  //
2111  // It is possible to execute some methods against arrays, because
2112  // all arrays are subclasses of java_lang_Object_, so we need to set
2113  // up a vtable.  We can just point at the one in java_lang_Object_.
2114  //
2115  // Array classes are simple enough that we don't need to do a full
2116  // link step.
2117  Thread* self = Thread::Current();
2118  SirtRef<mirror::Class> new_class(self, NULL);
2119  if (UNLIKELY(!init_done_)) {
2120    // Classes that were hand created, ie not by FindSystemClass
2121    if (strcmp(descriptor, "[Ljava/lang/Class;") == 0) {
2122      new_class.reset(GetClassRoot(kClassArrayClass));
2123    } else if (strcmp(descriptor, "[Ljava/lang/Object;") == 0) {
2124      new_class.reset(GetClassRoot(kObjectArrayClass));
2125    } else if (strcmp(descriptor, class_roots_descriptors_[kJavaLangStringArrayClass]) == 0) {
2126      new_class.reset(GetClassRoot(kJavaLangStringArrayClass));
2127    } else if (strcmp(descriptor,
2128                      class_roots_descriptors_[kJavaLangReflectArtMethodArrayClass]) == 0) {
2129      new_class.reset(GetClassRoot(kJavaLangReflectArtMethodArrayClass));
2130    } else if (strcmp(descriptor,
2131                      class_roots_descriptors_[kJavaLangReflectArtFieldArrayClass]) == 0) {
2132      new_class.reset(GetClassRoot(kJavaLangReflectArtFieldArrayClass));
2133    } else if (strcmp(descriptor, "[C") == 0) {
2134      new_class.reset(GetClassRoot(kCharArrayClass));
2135    } else if (strcmp(descriptor, "[I") == 0) {
2136      new_class.reset(GetClassRoot(kIntArrayClass));
2137    }
2138  }
2139  if (new_class.get() == NULL) {
2140    new_class.reset(AllocClass(self, sizeof(mirror::Class)));
2141    if (new_class.get() == NULL) {
2142      return NULL;
2143    }
2144    new_class->SetComponentType(component_type);
2145  }
2146  ObjectLock lock(self, new_class.get());  // Must hold lock on object when initializing.
2147  DCHECK(new_class->GetComponentType() != NULL);
2148  mirror::Class* java_lang_Object = GetClassRoot(kJavaLangObject);
2149  new_class->SetSuperClass(java_lang_Object);
2150  new_class->SetVTable(java_lang_Object->GetVTable());
2151  new_class->SetPrimitiveType(Primitive::kPrimNot);
2152  new_class->SetClassLoader(component_type->GetClassLoader());
2153  new_class->SetStatus(mirror::Class::kStatusInitialized, self);
2154  // don't need to set new_class->SetObjectSize(..)
2155  // because Object::SizeOf delegates to Array::SizeOf
2156
2157
2158  // All arrays have java/lang/Cloneable and java/io/Serializable as
2159  // interfaces.  We need to set that up here, so that stuff like
2160  // "instanceof" works right.
2161  //
2162  // Note: The GC could run during the call to FindSystemClass,
2163  // so we need to make sure the class object is GC-valid while we're in
2164  // there.  Do this by clearing the interface list so the GC will just
2165  // think that the entries are null.
2166
2167
2168  // Use the single, global copies of "interfaces" and "iftable"
2169  // (remember not to free them for arrays).
2170  CHECK(array_iftable_ != NULL);
2171  new_class->SetIfTable(array_iftable_);
2172
2173  // Inherit access flags from the component type.
2174  int access_flags = new_class->GetComponentType()->GetAccessFlags();
2175  // Lose any implementation detail flags; in particular, arrays aren't finalizable.
2176  access_flags &= kAccJavaFlagsMask;
2177  // Arrays can't be used as a superclass or interface, so we want to add "abstract final"
2178  // and remove "interface".
2179  access_flags |= kAccAbstract | kAccFinal;
2180  access_flags &= ~kAccInterface;
2181
2182  new_class->SetAccessFlags(access_flags);
2183
2184  mirror::Class* existing = InsertClass(descriptor, new_class.get(), Hash(descriptor));
2185  if (existing == NULL) {
2186    return new_class.get();
2187  }
2188  // Another thread must have loaded the class after we
2189  // started but before we finished.  Abandon what we've
2190  // done.
2191  //
2192  // (Yes, this happens.)
2193
2194  return existing;
2195}
2196
2197mirror::Class* ClassLinker::FindPrimitiveClass(char type) {
2198  switch (Primitive::GetType(type)) {
2199    case Primitive::kPrimByte:
2200      return GetClassRoot(kPrimitiveByte);
2201    case Primitive::kPrimChar:
2202      return GetClassRoot(kPrimitiveChar);
2203    case Primitive::kPrimDouble:
2204      return GetClassRoot(kPrimitiveDouble);
2205    case Primitive::kPrimFloat:
2206      return GetClassRoot(kPrimitiveFloat);
2207    case Primitive::kPrimInt:
2208      return GetClassRoot(kPrimitiveInt);
2209    case Primitive::kPrimLong:
2210      return GetClassRoot(kPrimitiveLong);
2211    case Primitive::kPrimShort:
2212      return GetClassRoot(kPrimitiveShort);
2213    case Primitive::kPrimBoolean:
2214      return GetClassRoot(kPrimitiveBoolean);
2215    case Primitive::kPrimVoid:
2216      return GetClassRoot(kPrimitiveVoid);
2217    case Primitive::kPrimNot:
2218      break;
2219  }
2220  std::string printable_type(PrintableChar(type));
2221  ThrowNoClassDefFoundError("Not a primitive type: %s", printable_type.c_str());
2222  return NULL;
2223}
2224
2225mirror::Class* ClassLinker::InsertClass(const char* descriptor, mirror::Class* klass,
2226                                        size_t hash) {
2227  if (VLOG_IS_ON(class_linker)) {
2228    mirror::DexCache* dex_cache = klass->GetDexCache();
2229    std::string source;
2230    if (dex_cache != NULL) {
2231      source += " from ";
2232      source += dex_cache->GetLocation()->ToModifiedUtf8();
2233    }
2234    LOG(INFO) << "Loaded class " << descriptor << source;
2235  }
2236  WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_);
2237  mirror::Class* existing =
2238      LookupClassFromTableLocked(descriptor, klass->GetClassLoader(), hash);
2239  if (existing != NULL) {
2240    return existing;
2241  }
2242  if (kIsDebugBuild && klass->GetClassLoader() == NULL && dex_cache_image_class_lookup_required_) {
2243    // Check a class loaded with the system class loader matches one in the image if the class
2244    // is in the image.
2245    existing = LookupClassFromImage(descriptor);
2246    if (existing != NULL) {
2247      CHECK(klass == existing);
2248    }
2249  }
2250  Runtime::Current()->GetHeap()->VerifyObject(klass);
2251  class_table_.insert(std::make_pair(hash, klass));
2252  class_table_dirty_ = true;
2253  return NULL;
2254}
2255
2256bool ClassLinker::RemoveClass(const char* descriptor, const mirror::ClassLoader* class_loader) {
2257  size_t hash = Hash(descriptor);
2258  WriterMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_);
2259  ClassHelper kh;
2260  for (auto it = class_table_.lower_bound(hash), end = class_table_.end(); it != end && it->first == hash;
2261       ++it) {
2262    mirror::Class* klass = it->second;
2263    kh.ChangeClass(klass);
2264    if ((klass->GetClassLoader() == class_loader) &&
2265        (strcmp(descriptor, kh.GetDescriptor()) == 0)) {
2266      class_table_.erase(it);
2267      return true;
2268    }
2269  }
2270  return false;
2271}
2272
2273mirror::Class* ClassLinker::LookupClass(const char* descriptor,
2274                                        const mirror::ClassLoader* class_loader) {
2275  size_t hash = Hash(descriptor);
2276  {
2277    ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_);
2278    mirror::Class* result = LookupClassFromTableLocked(descriptor, class_loader, hash);
2279    if (result != NULL) {
2280      return result;
2281    }
2282  }
2283  if (class_loader != NULL || !dex_cache_image_class_lookup_required_) {
2284    return NULL;
2285  } else {
2286    // Lookup failed but need to search dex_caches_.
2287    mirror::Class* result = LookupClassFromImage(descriptor);
2288    if (result != NULL) {
2289      InsertClass(descriptor, result, hash);
2290    } else {
2291      // Searching the image dex files/caches failed, we don't want to get into this situation
2292      // often as map searches are faster, so after kMaxFailedDexCacheLookups move all image
2293      // classes into the class table.
2294      const int32_t kMaxFailedDexCacheLookups = 1000;
2295      if (++failed_dex_cache_class_lookups_ > kMaxFailedDexCacheLookups) {
2296        MoveImageClassesToClassTable();
2297      }
2298    }
2299    return result;
2300  }
2301}
2302
2303mirror::Class* ClassLinker::LookupClassFromTableLocked(const char* descriptor,
2304                                                       const mirror::ClassLoader* class_loader,
2305                                                       size_t hash) {
2306  ClassHelper kh(NULL, this);
2307  auto end = class_table_.end();
2308  for (auto it = class_table_.lower_bound(hash); it != end && it->first == hash; ++it) {
2309    mirror::Class* klass = it->second;
2310    kh.ChangeClass(klass);
2311    if ((klass->GetClassLoader() == class_loader) &&
2312        (strcmp(descriptor, kh.GetDescriptor()) == 0)) {
2313      if (kIsDebugBuild) {
2314        // Check for duplicates in the table.
2315        for (++it; it != end && it->first == hash; ++it) {
2316          mirror::Class* klass2 = it->second;
2317          kh.ChangeClass(klass2);
2318          CHECK(!((klass2->GetClassLoader() == class_loader) &&
2319                  (strcmp(descriptor, kh.GetDescriptor()) == 0)))
2320              << PrettyClass(klass) << " " << klass << " " << klass->GetClassLoader() << " "
2321              << PrettyClass(klass2) << " " << klass2 << " " << klass2->GetClassLoader();
2322        }
2323      }
2324      return klass;
2325    }
2326  }
2327  return NULL;
2328}
2329
2330static mirror::ObjectArray<mirror::DexCache>* GetImageDexCaches()
2331    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
2332  gc::space::ImageSpace* image = Runtime::Current()->GetHeap()->GetImageSpace();
2333  CHECK(image != NULL);
2334  mirror::Object* root = image->GetImageHeader().GetImageRoot(ImageHeader::kDexCaches);
2335  return root->AsObjectArray<mirror::DexCache>();
2336}
2337
2338void ClassLinker::MoveImageClassesToClassTable() {
2339  Thread* self = Thread::Current();
2340  WriterMutexLock mu(self, *Locks::classlinker_classes_lock_);
2341  if (!dex_cache_image_class_lookup_required_) {
2342    return;  // All dex cache classes are already in the class table.
2343  }
2344  const char* old_no_suspend_cause =
2345      self->StartAssertNoThreadSuspension("Moving image classes to class table");
2346  mirror::ObjectArray<mirror::DexCache>* dex_caches = GetImageDexCaches();
2347  ClassHelper kh(NULL, this);
2348  for (int32_t i = 0; i < dex_caches->GetLength(); i++) {
2349    mirror::DexCache* dex_cache = dex_caches->Get(i);
2350    mirror::ObjectArray<mirror::Class>* types = dex_cache->GetResolvedTypes();
2351    for (int32_t j = 0; j < types->GetLength(); j++) {
2352      mirror::Class* klass = types->Get(j);
2353      if (klass != NULL) {
2354        kh.ChangeClass(klass);
2355        DCHECK(klass->GetClassLoader() == NULL);
2356        const char* descriptor = kh.GetDescriptor();
2357        size_t hash = Hash(descriptor);
2358        mirror::Class* existing = LookupClassFromTableLocked(descriptor, NULL, hash);
2359        if (existing != NULL) {
2360          CHECK(existing == klass) << PrettyClassAndClassLoader(existing) << " != "
2361              << PrettyClassAndClassLoader(klass);
2362        } else {
2363          class_table_.insert(std::make_pair(hash, klass));
2364        }
2365      }
2366    }
2367  }
2368  class_table_dirty_ = true;
2369  dex_cache_image_class_lookup_required_ = false;
2370  self->EndAssertNoThreadSuspension(old_no_suspend_cause);
2371}
2372
2373mirror::Class* ClassLinker::LookupClassFromImage(const char* descriptor) {
2374  Thread* self = Thread::Current();
2375  const char* old_no_suspend_cause =
2376      self->StartAssertNoThreadSuspension("Image class lookup");
2377  mirror::ObjectArray<mirror::DexCache>* dex_caches = GetImageDexCaches();
2378  for (int32_t i = 0; i < dex_caches->GetLength(); ++i) {
2379    mirror::DexCache* dex_cache = dex_caches->Get(i);
2380    const DexFile* dex_file = dex_cache->GetDexFile();
2381    // First search using the class def map, but don't bother for non-class types.
2382    if (descriptor[0] == 'L') {
2383      const DexFile::StringId* descriptor_string_id = dex_file->FindStringId(descriptor);
2384      if (descriptor_string_id != NULL) {
2385        const DexFile::TypeId* type_id =
2386            dex_file->FindTypeId(dex_file->GetIndexForStringId(*descriptor_string_id));
2387        if (type_id != NULL) {
2388          mirror::Class* klass = dex_cache->GetResolvedType(dex_file->GetIndexForTypeId(*type_id));
2389          if (klass != NULL) {
2390            self->EndAssertNoThreadSuspension(old_no_suspend_cause);
2391            return klass;
2392          }
2393        }
2394      }
2395    }
2396    // Now try binary searching the string/type index.
2397    const DexFile::StringId* string_id = dex_file->FindStringId(descriptor);
2398    if (string_id != NULL) {
2399      const DexFile::TypeId* type_id =
2400          dex_file->FindTypeId(dex_file->GetIndexForStringId(*string_id));
2401      if (type_id != NULL) {
2402        uint16_t type_idx = dex_file->GetIndexForTypeId(*type_id);
2403        mirror::Class* klass = dex_cache->GetResolvedType(type_idx);
2404        if (klass != NULL) {
2405          self->EndAssertNoThreadSuspension(old_no_suspend_cause);
2406          return klass;
2407        }
2408      }
2409    }
2410  }
2411  self->EndAssertNoThreadSuspension(old_no_suspend_cause);
2412  return NULL;
2413}
2414
2415void ClassLinker::LookupClasses(const char* descriptor, std::vector<mirror::Class*>& result) {
2416  result.clear();
2417  if (dex_cache_image_class_lookup_required_) {
2418    MoveImageClassesToClassTable();
2419  }
2420  size_t hash = Hash(descriptor);
2421  ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_);
2422  ClassHelper kh(NULL, this);
2423  for (auto it = class_table_.lower_bound(hash), end = class_table_.end();
2424      it != end && it->first == hash; ++it) {
2425    mirror::Class* klass = it->second;
2426    kh.ChangeClass(klass);
2427    if (strcmp(descriptor, kh.GetDescriptor()) == 0) {
2428      result.push_back(klass);
2429    }
2430  }
2431}
2432
2433void ClassLinker::VerifyClass(mirror::Class* klass) {
2434  // TODO: assert that the monitor on the Class is held
2435  Thread* self = Thread::Current();
2436  ObjectLock lock(self, klass);
2437
2438  // Don't attempt to re-verify if already sufficiently verified.
2439  if (klass->IsVerified() ||
2440      (klass->IsCompileTimeVerified() && Runtime::Current()->IsCompiler())) {
2441    return;
2442  }
2443
2444  // The class might already be erroneous, for example at compile time if we attempted to verify
2445  // this class as a parent to another.
2446  if (klass->IsErroneous()) {
2447    ThrowEarlierClassFailure(klass);
2448    return;
2449  }
2450
2451  if (klass->GetStatus() == mirror::Class::kStatusResolved) {
2452    klass->SetStatus(mirror::Class::kStatusVerifying, self);
2453  } else {
2454    CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime)
2455        << PrettyClass(klass);
2456    CHECK(!Runtime::Current()->IsCompiler());
2457    klass->SetStatus(mirror::Class::kStatusVerifyingAtRuntime, self);
2458  }
2459
2460  // Verify super class.
2461  SirtRef<mirror::Class> super(self, klass->GetSuperClass());
2462  if (super.get() != NULL) {
2463    // Acquire lock to prevent races on verifying the super class.
2464    ObjectLock lock(self, super.get());
2465
2466    if (!super->IsVerified() && !super->IsErroneous()) {
2467      VerifyClass(super.get());
2468    }
2469    if (!super->IsCompileTimeVerified()) {
2470      std::string error_msg(StringPrintf("Rejecting class %s that attempts to sub-class erroneous class %s",
2471                                         PrettyDescriptor(klass).c_str(),
2472                                         PrettyDescriptor(super.get()).c_str()));
2473      LOG(ERROR) << error_msg  << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8();
2474      SirtRef<mirror::Throwable> cause(self, self->GetException(NULL));
2475      if (cause.get() != NULL) {
2476        self->ClearException();
2477      }
2478      ThrowVerifyError(klass, "%s", error_msg.c_str());
2479      if (cause.get() != NULL) {
2480        self->GetException(NULL)->SetCause(cause.get());
2481      }
2482      klass->SetStatus(mirror::Class::kStatusError, self);
2483      return;
2484    }
2485  }
2486
2487  // Try to use verification information from the oat file, otherwise do runtime verification.
2488  const DexFile& dex_file = *klass->GetDexCache()->GetDexFile();
2489  mirror::Class::Status oat_file_class_status(mirror::Class::kStatusNotReady);
2490  bool preverified = VerifyClassUsingOatFile(dex_file, klass, oat_file_class_status);
2491  if (oat_file_class_status == mirror::Class::kStatusError) {
2492    VLOG(class_linker) << "Skipping runtime verification of erroneous class "
2493        << PrettyDescriptor(klass) << " in "
2494        << klass->GetDexCache()->GetLocation()->ToModifiedUtf8();
2495    ThrowVerifyError(klass, "Rejecting class %s because it failed compile-time verification",
2496                     PrettyDescriptor(klass).c_str());
2497    klass->SetStatus(mirror::Class::kStatusError, self);
2498    return;
2499  }
2500  verifier::MethodVerifier::FailureKind verifier_failure = verifier::MethodVerifier::kNoFailure;
2501  std::string error_msg;
2502  if (!preverified) {
2503    verifier_failure = verifier::MethodVerifier::VerifyClass(klass,
2504                                                             Runtime::Current()->IsCompiler(),
2505                                                             &error_msg);
2506  }
2507  if (preverified || verifier_failure != verifier::MethodVerifier::kHardFailure) {
2508    if (!preverified && verifier_failure != verifier::MethodVerifier::kNoFailure) {
2509      VLOG(class_linker) << "Soft verification failure in class " << PrettyDescriptor(klass)
2510          << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8()
2511          << " because: " << error_msg;
2512    }
2513    self->AssertNoPendingException();
2514    // Make sure all classes referenced by catch blocks are resolved.
2515    ResolveClassExceptionHandlerTypes(dex_file, klass);
2516    if (verifier_failure == verifier::MethodVerifier::kNoFailure) {
2517      // Even though there were no verifier failures we need to respect whether the super-class
2518      // was verified or requiring runtime reverification.
2519      if (super.get() == NULL || super->IsVerified()) {
2520        klass->SetStatus(mirror::Class::kStatusVerified, self);
2521      } else {
2522        CHECK_EQ(super->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime);
2523        klass->SetStatus(mirror::Class::kStatusRetryVerificationAtRuntime, self);
2524        // Pretend a soft failure occured so that we don't consider the class verified below.
2525        verifier_failure = verifier::MethodVerifier::kSoftFailure;
2526      }
2527    } else {
2528      CHECK_EQ(verifier_failure, verifier::MethodVerifier::kSoftFailure);
2529      // Soft failures at compile time should be retried at runtime. Soft
2530      // failures at runtime will be handled by slow paths in the generated
2531      // code. Set status accordingly.
2532      if (Runtime::Current()->IsCompiler()) {
2533        klass->SetStatus(mirror::Class::kStatusRetryVerificationAtRuntime, self);
2534      } else {
2535        klass->SetStatus(mirror::Class::kStatusVerified, self);
2536      }
2537    }
2538  } else {
2539    LOG(ERROR) << "Verification failed on class " << PrettyDescriptor(klass)
2540        << " in " << klass->GetDexCache()->GetLocation()->ToModifiedUtf8()
2541        << " because: " << error_msg;
2542    self->AssertNoPendingException();
2543    ThrowVerifyError(klass, "%s", error_msg.c_str());
2544    klass->SetStatus(mirror::Class::kStatusError, self);
2545  }
2546  if (preverified || verifier_failure == verifier::MethodVerifier::kNoFailure) {
2547    // Class is verified so we don't need to do any access check on its methods.
2548    // Let the interpreter know it by setting the kAccPreverified flag onto each
2549    // method.
2550    // Note: we're going here during compilation and at runtime. When we set the
2551    // kAccPreverified flag when compiling image classes, the flag is recorded
2552    // in the image and is set when loading the image.
2553    klass->SetPreverifiedFlagOnAllMethods();
2554  }
2555}
2556
2557bool ClassLinker::VerifyClassUsingOatFile(const DexFile& dex_file, mirror::Class* klass,
2558                                          mirror::Class::Status& oat_file_class_status) {
2559  // If we're compiling, we can only verify the class using the oat file if
2560  // we are not compiling the image or if the class we're verifying is not part of
2561  // the app.  In other words, we will only check for preverification of bootclasspath
2562  // classes.
2563  if (Runtime::Current()->IsCompiler()) {
2564    // Are we compiling the bootclasspath?
2565    if (!Runtime::Current()->UseCompileTimeClassPath()) {
2566      return false;
2567    }
2568    // We are compiling an app (not the image).
2569
2570    // Is this an app class? (I.e. not a bootclasspath class)
2571    if (klass->GetClassLoader() != NULL) {
2572      return false;
2573    }
2574  }
2575
2576  const OatFile* oat_file = FindOpenedOatFileForDexFile(dex_file);
2577  // Make this work with gtests, which do not set up the image properly.
2578  // TODO: we should clean up gtests to set up the image path properly.
2579  if (Runtime::Current()->IsCompiler() && (oat_file == NULL)) {
2580    return false;
2581  }
2582
2583  CHECK(oat_file != NULL) << dex_file.GetLocation() << " " << PrettyClass(klass);
2584  uint dex_location_checksum = dex_file.GetLocationChecksum();
2585  const OatFile::OatDexFile* oat_dex_file = oat_file->GetOatDexFile(dex_file.GetLocation().c_str(),
2586                                                                    &dex_location_checksum);
2587  CHECK(oat_dex_file != NULL) << dex_file.GetLocation() << " " << PrettyClass(klass);
2588  uint16_t class_def_index = klass->GetDexClassDefIndex();
2589  UniquePtr<const OatFile::OatClass> oat_class(oat_dex_file->GetOatClass(class_def_index));
2590  CHECK(oat_class.get() != NULL)
2591          << dex_file.GetLocation() << " " << PrettyClass(klass) << " "
2592          << ClassHelper(klass).GetDescriptor();
2593  oat_file_class_status = oat_class->GetStatus();
2594  if (oat_file_class_status == mirror::Class::kStatusVerified ||
2595      oat_file_class_status == mirror::Class::kStatusInitialized) {
2596      return true;
2597  }
2598  if (oat_file_class_status == mirror::Class::kStatusRetryVerificationAtRuntime) {
2599    // Compile time verification failed with a soft error. Compile time verification can fail
2600    // because we have incomplete type information. Consider the following:
2601    // class ... {
2602    //   Foo x;
2603    //   .... () {
2604    //     if (...) {
2605    //       v1 gets assigned a type of resolved class Foo
2606    //     } else {
2607    //       v1 gets assigned a type of unresolved class Bar
2608    //     }
2609    //     iput x = v1
2610    // } }
2611    // when we merge v1 following the if-the-else it results in Conflict
2612    // (see verifier::RegType::Merge) as we can't know the type of Bar and we could possibly be
2613    // allowing an unsafe assignment to the field x in the iput (javac may have compiled this as
2614    // it knew Bar was a sub-class of Foo, but for us this may have been moved into a separate apk
2615    // at compile time).
2616    return false;
2617  }
2618  if (oat_file_class_status == mirror::Class::kStatusError) {
2619    // Compile time verification failed with a hard error. This is caused by invalid instructions
2620    // in the class. These errors are unrecoverable.
2621    return false;
2622  }
2623  if (oat_file_class_status == mirror::Class::kStatusNotReady) {
2624    // Status is uninitialized if we couldn't determine the status at compile time, for example,
2625    // not loading the class.
2626    // TODO: when the verifier doesn't rely on Class-es failing to resolve/load the type hierarchy
2627    // isn't a problem and this case shouldn't occur
2628    return false;
2629  }
2630  LOG(FATAL) << "Unexpected class status: " << oat_file_class_status
2631             << " " << dex_file.GetLocation() << " " << PrettyClass(klass) << " "
2632             << ClassHelper(klass).GetDescriptor();
2633
2634  return false;
2635}
2636
2637void ClassLinker::ResolveClassExceptionHandlerTypes(const DexFile& dex_file, mirror::Class* klass) {
2638  for (size_t i = 0; i < klass->NumDirectMethods(); i++) {
2639    ResolveMethodExceptionHandlerTypes(dex_file, klass->GetDirectMethod(i));
2640  }
2641  for (size_t i = 0; i < klass->NumVirtualMethods(); i++) {
2642    ResolveMethodExceptionHandlerTypes(dex_file, klass->GetVirtualMethod(i));
2643  }
2644}
2645
2646void ClassLinker::ResolveMethodExceptionHandlerTypes(const DexFile& dex_file,
2647                                                     mirror::ArtMethod* method) {
2648  // similar to DexVerifier::ScanTryCatchBlocks and dex2oat's ResolveExceptionsForMethod.
2649  const DexFile::CodeItem* code_item = dex_file.GetCodeItem(method->GetCodeItemOffset());
2650  if (code_item == NULL) {
2651    return;  // native or abstract method
2652  }
2653  if (code_item->tries_size_ == 0) {
2654    return;  // nothing to process
2655  }
2656  const byte* handlers_ptr = DexFile::GetCatchHandlerData(*code_item, 0);
2657  uint32_t handlers_size = DecodeUnsignedLeb128(&handlers_ptr);
2658  ClassLinker* linker = Runtime::Current()->GetClassLinker();
2659  for (uint32_t idx = 0; idx < handlers_size; idx++) {
2660    CatchHandlerIterator iterator(handlers_ptr);
2661    for (; iterator.HasNext(); iterator.Next()) {
2662      // Ensure exception types are resolved so that they don't need resolution to be delivered,
2663      // unresolved exception types will be ignored by exception delivery
2664      if (iterator.GetHandlerTypeIndex() != DexFile::kDexNoIndex16) {
2665        mirror::Class* exception_type = linker->ResolveType(iterator.GetHandlerTypeIndex(), method);
2666        if (exception_type == NULL) {
2667          DCHECK(Thread::Current()->IsExceptionPending());
2668          Thread::Current()->ClearException();
2669        }
2670      }
2671    }
2672    handlers_ptr = iterator.EndDataPointer();
2673  }
2674}
2675
2676static void CheckProxyConstructor(mirror::ArtMethod* constructor);
2677static void CheckProxyMethod(mirror::ArtMethod* method,
2678                             SirtRef<mirror::ArtMethod>& prototype);
2679
2680mirror::Class* ClassLinker::CreateProxyClass(mirror::String* name,
2681                                             mirror::ObjectArray<mirror::Class>* interfaces,
2682                                             mirror::ClassLoader* loader,
2683                                             mirror::ObjectArray<mirror::ArtMethod>* methods,
2684                                             mirror::ObjectArray<mirror::ObjectArray<mirror::Class> >* throws) {
2685  Thread* self = Thread::Current();
2686  SirtRef<mirror::Class> klass(self, AllocClass(self, GetClassRoot(kJavaLangClass),
2687                                                sizeof(mirror::SynthesizedProxyClass)));
2688  if (klass.get() == NULL) {
2689    CHECK(self->IsExceptionPending());  // OOME.
2690    return NULL;
2691  }
2692  DCHECK(klass->GetClass() != NULL);
2693  klass->SetObjectSize(sizeof(mirror::Proxy));
2694  klass->SetAccessFlags(kAccClassIsProxy | kAccPublic | kAccFinal);
2695  klass->SetClassLoader(loader);
2696  DCHECK_EQ(klass->GetPrimitiveType(), Primitive::kPrimNot);
2697  klass->SetName(name);
2698  mirror::Class* proxy_class = GetClassRoot(kJavaLangReflectProxy);
2699  klass->SetDexCache(proxy_class->GetDexCache());
2700  klass->SetStatus(mirror::Class::kStatusIdx, self);
2701
2702  // Instance fields are inherited, but we add a couple of static fields...
2703  {
2704    mirror::ObjectArray<mirror::ArtField>* sfields = AllocArtFieldArray(self, 2);
2705    if (UNLIKELY(sfields == NULL)) {
2706      CHECK(self->IsExceptionPending());  // OOME.
2707      return NULL;
2708    }
2709    klass->SetSFields(sfields);
2710  }
2711  // 1. Create a static field 'interfaces' that holds the _declared_ interfaces implemented by
2712  // our proxy, so Class.getInterfaces doesn't return the flattened set.
2713  SirtRef<mirror::ArtField> interfaces_sfield(self, AllocArtField(self));
2714  if (UNLIKELY(interfaces_sfield.get() == NULL)) {
2715    CHECK(self->IsExceptionPending());  // OOME.
2716    return NULL;
2717  }
2718  klass->SetStaticField(0, interfaces_sfield.get());
2719  interfaces_sfield->SetDexFieldIndex(0);
2720  interfaces_sfield->SetDeclaringClass(klass.get());
2721  interfaces_sfield->SetAccessFlags(kAccStatic | kAccPublic | kAccFinal);
2722  // 2. Create a static field 'throws' that holds exceptions thrown by our methods.
2723  SirtRef<mirror::ArtField> throws_sfield(self, AllocArtField(self));
2724  if (UNLIKELY(throws_sfield.get() == NULL)) {
2725    CHECK(self->IsExceptionPending());  // OOME.
2726    return NULL;
2727  }
2728  klass->SetStaticField(1, throws_sfield.get());
2729  throws_sfield->SetDexFieldIndex(1);
2730  throws_sfield->SetDeclaringClass(klass.get());
2731  throws_sfield->SetAccessFlags(kAccStatic | kAccPublic | kAccFinal);
2732
2733  // Proxies have 1 direct method, the constructor
2734  {
2735    mirror::ObjectArray<mirror::ArtMethod>* directs =
2736      AllocArtMethodArray(self, 1);
2737    if (UNLIKELY(directs == NULL)) {
2738      CHECK(self->IsExceptionPending());  // OOME.
2739      return NULL;
2740    }
2741    klass->SetDirectMethods(directs);
2742    mirror::ArtMethod* constructor = CreateProxyConstructor(self, klass, proxy_class);
2743    if (UNLIKELY(constructor == NULL)) {
2744      CHECK(self->IsExceptionPending());  // OOME.
2745      return NULL;
2746    }
2747    klass->SetDirectMethod(0, constructor);
2748  }
2749
2750  // Create virtual method using specified prototypes
2751  size_t num_virtual_methods = methods->GetLength();
2752  {
2753    mirror::ObjectArray<mirror::ArtMethod>* virtuals =
2754        AllocArtMethodArray(self, num_virtual_methods);
2755    if (UNLIKELY(virtuals == NULL)) {
2756      CHECK(self->IsExceptionPending());  // OOME.
2757      return NULL;
2758    }
2759    klass->SetVirtualMethods(virtuals);
2760  }
2761  for (size_t i = 0; i < num_virtual_methods; ++i) {
2762    SirtRef<mirror::ArtMethod> prototype(self, methods->Get(i));
2763    mirror::ArtMethod* clone = CreateProxyMethod(self, klass, prototype);
2764    if (UNLIKELY(clone == NULL)) {
2765      CHECK(self->IsExceptionPending());  // OOME.
2766      return NULL;
2767    }
2768    klass->SetVirtualMethod(i, clone);
2769  }
2770
2771  klass->SetSuperClass(proxy_class);  // The super class is java.lang.reflect.Proxy
2772  klass->SetStatus(mirror::Class::kStatusLoaded, self);  // Class is now effectively in the loaded state
2773  self->AssertNoPendingException();
2774
2775  {
2776    ObjectLock lock(self, klass.get());  // Must hold lock on object when resolved.
2777    // Link the fields and virtual methods, creating vtable and iftables
2778    if (!LinkClass(klass, interfaces, self)) {
2779      klass->SetStatus(mirror::Class::kStatusError, self);
2780      return NULL;
2781    }
2782
2783    interfaces_sfield->SetObject(klass.get(), interfaces);
2784    throws_sfield->SetObject(klass.get(), throws);
2785    klass->SetStatus(mirror::Class::kStatusInitialized, self);
2786  }
2787
2788  // sanity checks
2789  if (kIsDebugBuild) {
2790    CHECK(klass->GetIFields() == NULL);
2791    CheckProxyConstructor(klass->GetDirectMethod(0));
2792    for (size_t i = 0; i < num_virtual_methods; ++i) {
2793      SirtRef<mirror::ArtMethod> prototype(self, methods->Get(i));
2794      CheckProxyMethod(klass->GetVirtualMethod(i), prototype);
2795    }
2796
2797    std::string interfaces_field_name(StringPrintf("java.lang.Class[] %s.interfaces",
2798                                                   name->ToModifiedUtf8().c_str()));
2799    CHECK_EQ(PrettyField(klass->GetStaticField(0)), interfaces_field_name);
2800
2801    std::string throws_field_name(StringPrintf("java.lang.Class[][] %s.throws",
2802                                               name->ToModifiedUtf8().c_str()));
2803    CHECK_EQ(PrettyField(klass->GetStaticField(1)), throws_field_name);
2804
2805    mirror::SynthesizedProxyClass* synth_proxy_class =
2806        down_cast<mirror::SynthesizedProxyClass*>(klass.get());
2807    CHECK_EQ(synth_proxy_class->GetInterfaces(), interfaces);
2808    CHECK_EQ(synth_proxy_class->GetThrows(), throws);
2809  }
2810  std::string descriptor(GetDescriptorForProxy(klass.get()));
2811  mirror::Class* existing = InsertClass(descriptor.c_str(), klass.get(), Hash(descriptor.c_str()));
2812  CHECK(existing == nullptr);
2813  return klass.get();
2814}
2815
2816std::string ClassLinker::GetDescriptorForProxy(const mirror::Class* proxy_class) {
2817  DCHECK(proxy_class->IsProxyClass());
2818  mirror::String* name = proxy_class->GetName();
2819  DCHECK(name != NULL);
2820  return DotToDescriptor(name->ToModifiedUtf8().c_str());
2821}
2822
2823mirror::ArtMethod* ClassLinker::FindMethodForProxy(const mirror::Class* proxy_class,
2824                                                        const mirror::ArtMethod* proxy_method) {
2825  DCHECK(proxy_class->IsProxyClass());
2826  DCHECK(proxy_method->IsProxyMethod());
2827  // Locate the dex cache of the original interface/Object
2828  mirror::DexCache* dex_cache = NULL;
2829  {
2830    mirror::ObjectArray<mirror::Class>* resolved_types = proxy_method->GetDexCacheResolvedTypes();
2831    ReaderMutexLock mu(Thread::Current(), dex_lock_);
2832    for (size_t i = 0; i != dex_caches_.size(); ++i) {
2833      if (dex_caches_[i]->GetResolvedTypes() == resolved_types) {
2834        dex_cache = dex_caches_[i];
2835        break;
2836      }
2837    }
2838  }
2839  CHECK(dex_cache != NULL);
2840  uint32_t method_idx = proxy_method->GetDexMethodIndex();
2841  mirror::ArtMethod* resolved_method = dex_cache->GetResolvedMethod(method_idx);
2842  CHECK(resolved_method != NULL);
2843  return resolved_method;
2844}
2845
2846
2847mirror::ArtMethod* ClassLinker::CreateProxyConstructor(Thread* self,
2848                                                       SirtRef<mirror::Class>& klass,
2849                                                       mirror::Class* proxy_class) {
2850  // Create constructor for Proxy that must initialize h
2851  mirror::ObjectArray<mirror::ArtMethod>* proxy_direct_methods =
2852      proxy_class->GetDirectMethods();
2853  CHECK_EQ(proxy_direct_methods->GetLength(), 16);
2854  mirror::ArtMethod* proxy_constructor = proxy_direct_methods->Get(2);
2855  // Clone the existing constructor of Proxy (our constructor would just invoke it so steal its
2856  // code_ too)
2857  mirror::ArtMethod* constructor =
2858      down_cast<mirror::ArtMethod*>(proxy_constructor->Clone(self));
2859  if (constructor == NULL) {
2860    CHECK(self->IsExceptionPending());  // OOME.
2861    return NULL;
2862  }
2863  // Make this constructor public and fix the class to be our Proxy version
2864  constructor->SetAccessFlags((constructor->GetAccessFlags() & ~kAccProtected) | kAccPublic);
2865  constructor->SetDeclaringClass(klass.get());
2866  return constructor;
2867}
2868
2869static void CheckProxyConstructor(mirror::ArtMethod* constructor)
2870    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
2871  CHECK(constructor->IsConstructor());
2872  MethodHelper mh(constructor);
2873  CHECK_STREQ(mh.GetName(), "<init>");
2874  CHECK_STREQ(mh.GetSignature().ToString().c_str(), "(Ljava/lang/reflect/InvocationHandler;)V");
2875  DCHECK(constructor->IsPublic());
2876}
2877
2878mirror::ArtMethod* ClassLinker::CreateProxyMethod(Thread* self, SirtRef<mirror::Class>& klass,
2879                                                  SirtRef<mirror::ArtMethod>& prototype) {
2880  // Ensure prototype is in dex cache so that we can use the dex cache to look up the overridden
2881  // prototype method
2882  prototype->GetDeclaringClass()->GetDexCache()->SetResolvedMethod(prototype->GetDexMethodIndex(),
2883                                                                   prototype.get());
2884  // We steal everything from the prototype (such as DexCache, invoke stub, etc.) then specialize
2885  // as necessary
2886  mirror::ArtMethod* method = down_cast<mirror::ArtMethod*>(prototype->Clone(self));
2887  if (UNLIKELY(method == NULL)) {
2888    CHECK(self->IsExceptionPending());  // OOME.
2889    return NULL;
2890  }
2891
2892  // Set class to be the concrete proxy class and clear the abstract flag, modify exceptions to
2893  // the intersection of throw exceptions as defined in Proxy
2894  method->SetDeclaringClass(klass.get());
2895  method->SetAccessFlags((method->GetAccessFlags() & ~kAccAbstract) | kAccFinal);
2896
2897  // At runtime the method looks like a reference and argument saving method, clone the code
2898  // related parameters from this method.
2899  mirror::ArtMethod* refs_and_args =
2900      Runtime::Current()->GetCalleeSaveMethod(Runtime::kRefsAndArgs);
2901  method->SetCoreSpillMask(refs_and_args->GetCoreSpillMask());
2902  method->SetFpSpillMask(refs_and_args->GetFpSpillMask());
2903  method->SetFrameSizeInBytes(refs_and_args->GetFrameSizeInBytes());
2904  method->SetEntryPointFromCompiledCode(GetProxyInvokeHandler());
2905  method->SetEntryPointFromInterpreter(artInterpreterToCompiledCodeBridge);
2906
2907  return method;
2908}
2909
2910static void CheckProxyMethod(mirror::ArtMethod* method,
2911                             SirtRef<mirror::ArtMethod>& prototype)
2912    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
2913  // Basic sanity
2914  CHECK(!prototype->IsFinal());
2915  CHECK(method->IsFinal());
2916  CHECK(!method->IsAbstract());
2917
2918  // The proxy method doesn't have its own dex cache or dex file and so it steals those of its
2919  // interface prototype. The exception to this are Constructors and the Class of the Proxy itself.
2920  CHECK_EQ(prototype->GetDexCacheStrings(), method->GetDexCacheStrings());
2921  CHECK_EQ(prototype->GetDexCacheResolvedMethods(), method->GetDexCacheResolvedMethods());
2922  CHECK_EQ(prototype->GetDexCacheResolvedTypes(), method->GetDexCacheResolvedTypes());
2923  CHECK_EQ(prototype->GetDexCacheInitializedStaticStorage(),
2924           method->GetDexCacheInitializedStaticStorage());
2925  CHECK_EQ(prototype->GetDexMethodIndex(), method->GetDexMethodIndex());
2926
2927  MethodHelper mh(method);
2928  MethodHelper mh2(prototype.get());
2929  CHECK_STREQ(mh.GetName(), mh2.GetName());
2930  CHECK_STREQ(mh.GetShorty(), mh2.GetShorty());
2931  // More complex sanity - via dex cache
2932  CHECK_EQ(mh.GetReturnType(), mh2.GetReturnType());
2933}
2934
2935static bool CanWeInitializeClass(mirror::Class* klass, bool can_init_statics,
2936                                 bool can_init_parents)
2937    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
2938  if (can_init_statics && can_init_statics) {
2939    return true;
2940  }
2941  if (!can_init_statics) {
2942    // Check if there's a class initializer.
2943    mirror::ArtMethod* clinit = klass->FindClassInitializer();
2944    if (clinit != NULL) {
2945      return false;
2946    }
2947    // Check if there are encoded static values needing initialization.
2948    if (klass->NumStaticFields() != 0) {
2949      ClassHelper kh(klass);
2950      const DexFile::ClassDef* dex_class_def = kh.GetClassDef();
2951      DCHECK(dex_class_def != NULL);
2952      if (dex_class_def->static_values_off_ != 0) {
2953        return false;
2954      }
2955    }
2956  }
2957  if (!klass->IsInterface() && klass->HasSuperClass()) {
2958    mirror::Class* super_class = klass->GetSuperClass();
2959    if (!can_init_parents && !super_class->IsInitialized()) {
2960      return false;
2961    } else {
2962      if (!CanWeInitializeClass(super_class, can_init_statics, true)) {
2963        return false;
2964      }
2965    }
2966  }
2967  return true;
2968}
2969
2970bool ClassLinker::InitializeClass(mirror::Class* klass, bool can_init_statics,
2971                                  bool can_init_parents) {
2972  // see JLS 3rd edition, 12.4.2 "Detailed Initialization Procedure" for the locking protocol
2973
2974  // Are we already initialized and therefore done?
2975  // Note: we differ from the JLS here as we don't do this under the lock, this is benign as
2976  // an initialized class will never change its state.
2977  if (klass->IsInitialized()) {
2978    return true;
2979  }
2980
2981  // Fast fail if initialization requires a full runtime. Not part of the JLS.
2982  if (!CanWeInitializeClass(klass, can_init_statics, can_init_parents)) {
2983    return false;
2984  }
2985
2986  Thread* self = Thread::Current();
2987  uint64_t t0;
2988  {
2989    ObjectLock lock(self, klass);
2990
2991    // Re-check under the lock in case another thread initialized ahead of us.
2992    if (klass->IsInitialized()) {
2993      return true;
2994    }
2995
2996    // Was the class already found to be erroneous? Done under the lock to match the JLS.
2997    if (klass->IsErroneous()) {
2998      ThrowEarlierClassFailure(klass);
2999      return false;
3000    }
3001
3002    CHECK(klass->IsResolved()) << PrettyClass(klass) << ": state=" << klass->GetStatus();
3003
3004    if (!klass->IsVerified()) {
3005      VerifyClass(klass);
3006      if (!klass->IsVerified()) {
3007        // We failed to verify, expect either the klass to be erroneous or verification failed at
3008        // compile time.
3009        if (klass->IsErroneous()) {
3010          CHECK(self->IsExceptionPending());
3011        } else {
3012          CHECK(Runtime::Current()->IsCompiler());
3013          CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime);
3014        }
3015        return false;
3016      }
3017    }
3018
3019    // If the class is kStatusInitializing, either this thread is
3020    // initializing higher up the stack or another thread has beat us
3021    // to initializing and we need to wait. Either way, this
3022    // invocation of InitializeClass will not be responsible for
3023    // running <clinit> and will return.
3024    if (klass->GetStatus() == mirror::Class::kStatusInitializing) {
3025      // We caught somebody else in the act; was it us?
3026      if (klass->GetClinitThreadId() == self->GetTid()) {
3027        // Yes. That's fine. Return so we can continue initializing.
3028        return true;
3029      }
3030      // No. That's fine. Wait for another thread to finish initializing.
3031      return WaitForInitializeClass(klass, self, lock);
3032    }
3033
3034    if (!ValidateSuperClassDescriptors(klass)) {
3035      klass->SetStatus(mirror::Class::kStatusError, self);
3036      return false;
3037    }
3038
3039    CHECK_EQ(klass->GetStatus(), mirror::Class::kStatusVerified) << PrettyClass(klass);
3040
3041    // From here out other threads may observe that we're initializing and so changes of state
3042    // require the a notification.
3043    klass->SetClinitThreadId(self->GetTid());
3044    klass->SetStatus(mirror::Class::kStatusInitializing, self);
3045
3046    t0 = NanoTime();
3047  }
3048
3049  // Initialize super classes, must be done while initializing for the JLS.
3050  if (!klass->IsInterface() && klass->HasSuperClass()) {
3051    mirror::Class* super_class = klass->GetSuperClass();
3052    if (!super_class->IsInitialized()) {
3053      CHECK(!super_class->IsInterface());
3054      CHECK(can_init_parents);
3055      bool super_initialized = InitializeClass(super_class, can_init_statics, true);
3056      if (!super_initialized) {
3057        // The super class was verified ahead of entering initializing, we should only be here if
3058        // the super class became erroneous due to initialization.
3059        CHECK(super_class->IsErroneous() && self->IsExceptionPending())
3060            << "Super class initialization failed for " << PrettyDescriptor(super_class)
3061            << " that has unexpected status " << super_class->GetStatus()
3062            << "\nPending exception:\n"
3063            << (self->GetException(NULL) != NULL ? self->GetException(NULL)->Dump() : "");
3064        ObjectLock lock(self, klass);
3065        // Initialization failed because the super-class is erroneous.
3066        klass->SetStatus(mirror::Class::kStatusError, self);
3067        return false;
3068      }
3069    }
3070  }
3071
3072  if (klass->NumStaticFields() > 0) {
3073    ClassHelper kh(klass);
3074    const DexFile::ClassDef* dex_class_def = kh.GetClassDef();
3075    CHECK(dex_class_def != NULL);
3076    const DexFile& dex_file = kh.GetDexFile();
3077    EncodedStaticFieldValueIterator it(dex_file, kh.GetDexCache(), klass->GetClassLoader(),
3078                                       this, *dex_class_def);
3079    if (it.HasNext()) {
3080      CHECK(can_init_statics);
3081      // We reordered the fields, so we need to be able to map the field indexes to the right fields.
3082      SafeMap<uint32_t, mirror::ArtField*> field_map;
3083      ConstructFieldMap(dex_file, *dex_class_def, klass, field_map);
3084      for (size_t i = 0; it.HasNext(); i++, it.Next()) {
3085        it.ReadValueToField(field_map.Get(i));
3086      }
3087    }
3088  }
3089
3090  mirror::ArtMethod* clinit = klass->FindClassInitializer();
3091  if (clinit != NULL) {
3092    CHECK(can_init_statics);
3093    if (LIKELY(Runtime::Current()->IsStarted())) {
3094      JValue result;
3095      clinit->Invoke(self, NULL, 0, &result, 'V');
3096    } else {
3097      art::interpreter::EnterInterpreterFromInvoke(self, clinit, NULL, NULL, NULL);
3098    }
3099  }
3100
3101  // Opportunistically set static method trampolines to their destination.
3102  FixupStaticTrampolines(klass);
3103
3104  uint64_t t1 = NanoTime();
3105
3106  bool success = true;
3107  {
3108    ObjectLock lock(self, klass);
3109
3110    if (self->IsExceptionPending()) {
3111      WrapExceptionInInitializer();
3112      klass->SetStatus(mirror::Class::kStatusError, self);
3113      success = false;
3114    } else {
3115      RuntimeStats* global_stats = Runtime::Current()->GetStats();
3116      RuntimeStats* thread_stats = self->GetStats();
3117      ++global_stats->class_init_count;
3118      ++thread_stats->class_init_count;
3119      global_stats->class_init_time_ns += (t1 - t0);
3120      thread_stats->class_init_time_ns += (t1 - t0);
3121      // Set the class as initialized except if failed to initialize static fields.
3122      klass->SetStatus(mirror::Class::kStatusInitialized, self);
3123      if (VLOG_IS_ON(class_linker)) {
3124        ClassHelper kh(klass);
3125        LOG(INFO) << "Initialized class " << kh.GetDescriptor() << " from " << kh.GetLocation();
3126      }
3127    }
3128  }
3129  return success;
3130}
3131
3132bool ClassLinker::WaitForInitializeClass(mirror::Class* klass, Thread* self, ObjectLock& lock)
3133    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
3134  while (true) {
3135    self->AssertNoPendingException();
3136    CHECK(!klass->IsInitialized());
3137    lock.WaitIgnoringInterrupts();
3138
3139    // When we wake up, repeat the test for init-in-progress.  If
3140    // there's an exception pending (only possible if
3141    // "interruptShouldThrow" was set), bail out.
3142    if (self->IsExceptionPending()) {
3143      WrapExceptionInInitializer();
3144      klass->SetStatus(mirror::Class::kStatusError, self);
3145      return false;
3146    }
3147    // Spurious wakeup? Go back to waiting.
3148    if (klass->GetStatus() == mirror::Class::kStatusInitializing) {
3149      continue;
3150    }
3151    if (klass->GetStatus() == mirror::Class::kStatusVerified && Runtime::Current()->IsCompiler()) {
3152      // Compile time initialization failed.
3153      return false;
3154    }
3155    if (klass->IsErroneous()) {
3156      // The caller wants an exception, but it was thrown in a
3157      // different thread.  Synthesize one here.
3158      ThrowNoClassDefFoundError("<clinit> failed for class %s; see exception in other thread",
3159                                PrettyDescriptor(klass).c_str());
3160      return false;
3161    }
3162    if (klass->IsInitialized()) {
3163      return true;
3164    }
3165    LOG(FATAL) << "Unexpected class status. " << PrettyClass(klass) << " is " << klass->GetStatus();
3166  }
3167  LOG(FATAL) << "Not Reached" << PrettyClass(klass);
3168}
3169
3170bool ClassLinker::ValidateSuperClassDescriptors(const mirror::Class* klass) {
3171  if (klass->IsInterface()) {
3172    return true;
3173  }
3174  // begin with the methods local to the superclass
3175  if (klass->HasSuperClass() &&
3176      klass->GetClassLoader() != klass->GetSuperClass()->GetClassLoader()) {
3177    const mirror::Class* super = klass->GetSuperClass();
3178    for (int i = super->GetVTable()->GetLength() - 1; i >= 0; --i) {
3179      const mirror::ArtMethod* method = klass->GetVTable()->Get(i);
3180      if (method != super->GetVTable()->Get(i) &&
3181          !IsSameMethodSignatureInDifferentClassContexts(method, super, klass)) {
3182        ThrowLinkageError(klass, "Class %s method %s resolves differently in superclass %s",
3183                          PrettyDescriptor(klass).c_str(), PrettyMethod(method).c_str(),
3184                          PrettyDescriptor(super).c_str());
3185        return false;
3186      }
3187    }
3188  }
3189  mirror::IfTable* iftable = klass->GetIfTable();
3190  for (int32_t i = 0; i < klass->GetIfTableCount(); ++i) {
3191    mirror::Class* interface = iftable->GetInterface(i);
3192    if (klass->GetClassLoader() != interface->GetClassLoader()) {
3193      for (size_t j = 0; j < interface->NumVirtualMethods(); ++j) {
3194        const mirror::ArtMethod* method = iftable->GetMethodArray(i)->Get(j);
3195        if (!IsSameMethodSignatureInDifferentClassContexts(method, interface,
3196                                                           method->GetDeclaringClass())) {
3197          ThrowLinkageError(klass, "Class %s method %s resolves differently in interface %s",
3198                            PrettyDescriptor(method->GetDeclaringClass()).c_str(),
3199                            PrettyMethod(method).c_str(),
3200                            PrettyDescriptor(interface).c_str());
3201          return false;
3202        }
3203      }
3204    }
3205  }
3206  return true;
3207}
3208
3209// Returns true if classes referenced by the signature of the method are the
3210// same classes in klass1 as they are in klass2.
3211bool ClassLinker::IsSameMethodSignatureInDifferentClassContexts(const mirror::ArtMethod* method,
3212                                                                const mirror::Class* klass1,
3213                                                                const mirror::Class* klass2) {
3214  if (klass1 == klass2) {
3215    return true;
3216  }
3217  const DexFile& dex_file = *method->GetDeclaringClass()->GetDexCache()->GetDexFile();
3218  const DexFile::ProtoId& proto_id =
3219      dex_file.GetMethodPrototype(dex_file.GetMethodId(method->GetDexMethodIndex()));
3220  for (DexFileParameterIterator it(dex_file, proto_id); it.HasNext(); it.Next()) {
3221    const char* descriptor = it.GetDescriptor();
3222    if (descriptor == NULL) {
3223      break;
3224    }
3225    if (descriptor[0] == 'L' || descriptor[0] == '[') {
3226      // Found a non-primitive type.
3227      if (!IsSameDescriptorInDifferentClassContexts(descriptor, klass1, klass2)) {
3228        return false;
3229      }
3230    }
3231  }
3232  // Check the return type
3233  const char* descriptor = dex_file.GetReturnTypeDescriptor(proto_id);
3234  if (descriptor[0] == 'L' || descriptor[0] == '[') {
3235    if (!IsSameDescriptorInDifferentClassContexts(descriptor, klass1, klass2)) {
3236      return false;
3237    }
3238  }
3239  return true;
3240}
3241
3242// Returns true if the descriptor resolves to the same class in the context of klass1 and klass2.
3243bool ClassLinker::IsSameDescriptorInDifferentClassContexts(const char* descriptor,
3244                                                           const mirror::Class* klass1,
3245                                                           const mirror::Class* klass2) {
3246  CHECK(descriptor != NULL);
3247  CHECK(klass1 != NULL);
3248  CHECK(klass2 != NULL);
3249  if (klass1 == klass2) {
3250    return true;
3251  }
3252  mirror::Class* found1 = FindClass(descriptor, klass1->GetClassLoader());
3253  if (found1 == NULL) {
3254    Thread::Current()->ClearException();
3255  }
3256  mirror::Class* found2 = FindClass(descriptor, klass2->GetClassLoader());
3257  if (found2 == NULL) {
3258    Thread::Current()->ClearException();
3259  }
3260  return found1 == found2;
3261}
3262
3263bool ClassLinker::EnsureInitialized(mirror::Class* c, bool can_init_fields, bool can_init_parents) {
3264  DCHECK(c != NULL);
3265  if (c->IsInitialized()) {
3266    return true;
3267  }
3268
3269  bool success = InitializeClass(c, can_init_fields, can_init_parents);
3270  if (!success) {
3271    Thread* self = Thread::Current();
3272    CHECK(self->IsExceptionPending() || !can_init_fields || !can_init_parents) << PrettyClass(c);
3273  }
3274  return success;
3275}
3276
3277void ClassLinker::ConstructFieldMap(const DexFile& dex_file, const DexFile::ClassDef& dex_class_def,
3278                                    mirror::Class* c, SafeMap<uint32_t, mirror::ArtField*>& field_map) {
3279  mirror::ClassLoader* cl = c->GetClassLoader();
3280  const byte* class_data = dex_file.GetClassData(dex_class_def);
3281  ClassDataItemIterator it(dex_file, class_data);
3282  for (size_t i = 0; it.HasNextStaticField(); i++, it.Next()) {
3283    field_map.Put(i, ResolveField(dex_file, it.GetMemberIndex(), c->GetDexCache(), cl, true));
3284  }
3285}
3286
3287bool ClassLinker::LinkClass(SirtRef<mirror::Class>& klass,
3288                            mirror::ObjectArray<mirror::Class>* interfaces, Thread* self) {
3289  CHECK_EQ(mirror::Class::kStatusLoaded, klass->GetStatus());
3290  if (!LinkSuperClass(klass)) {
3291    return false;
3292  }
3293  if (!LinkMethods(klass, interfaces)) {
3294    return false;
3295  }
3296  if (!LinkInstanceFields(klass)) {
3297    return false;
3298  }
3299  if (!LinkStaticFields(klass)) {
3300    return false;
3301  }
3302  CreateReferenceInstanceOffsets(klass);
3303  CreateReferenceStaticOffsets(klass);
3304  CHECK_EQ(mirror::Class::kStatusLoaded, klass->GetStatus());
3305  klass->SetStatus(mirror::Class::kStatusResolved, self);
3306  return true;
3307}
3308
3309bool ClassLinker::LoadSuperAndInterfaces(SirtRef<mirror::Class>& klass, const DexFile& dex_file) {
3310  CHECK_EQ(mirror::Class::kStatusIdx, klass->GetStatus());
3311  const DexFile::ClassDef& class_def = dex_file.GetClassDef(klass->GetDexClassDefIndex());
3312  uint16_t super_class_idx = class_def.superclass_idx_;
3313  if (super_class_idx != DexFile::kDexNoIndex16) {
3314    mirror::Class* super_class = ResolveType(dex_file, super_class_idx, klass.get());
3315    if (super_class == NULL) {
3316      DCHECK(Thread::Current()->IsExceptionPending());
3317      return false;
3318    }
3319    // Verify
3320    if (!klass->CanAccess(super_class)) {
3321      ThrowIllegalAccessError(klass.get(), "Class %s extended by class %s is inaccessible",
3322                              PrettyDescriptor(super_class).c_str(),
3323                              PrettyDescriptor(klass.get()).c_str());
3324      return false;
3325    }
3326    klass->SetSuperClass(super_class);
3327  }
3328  const DexFile::TypeList* interfaces = dex_file.GetInterfacesList(class_def);
3329  if (interfaces != NULL) {
3330    for (size_t i = 0; i < interfaces->Size(); i++) {
3331      uint16_t idx = interfaces->GetTypeItem(i).type_idx_;
3332      mirror::Class* interface = ResolveType(dex_file, idx, klass.get());
3333      if (interface == NULL) {
3334        DCHECK(Thread::Current()->IsExceptionPending());
3335        return false;
3336      }
3337      // Verify
3338      if (!klass->CanAccess(interface)) {
3339        // TODO: the RI seemed to ignore this in my testing.
3340        ThrowIllegalAccessError(klass.get(), "Interface %s implemented by class %s is inaccessible",
3341                                PrettyDescriptor(interface).c_str(),
3342                                PrettyDescriptor(klass.get()).c_str());
3343        return false;
3344      }
3345    }
3346  }
3347  // Mark the class as loaded.
3348  klass->SetStatus(mirror::Class::kStatusLoaded, NULL);
3349  return true;
3350}
3351
3352bool ClassLinker::LinkSuperClass(SirtRef<mirror::Class>& klass) {
3353  CHECK(!klass->IsPrimitive());
3354  mirror::Class* super = klass->GetSuperClass();
3355  if (klass.get() == GetClassRoot(kJavaLangObject)) {
3356    if (super != NULL) {
3357      ThrowClassFormatError(klass.get(), "java.lang.Object must not have a superclass");
3358      return false;
3359    }
3360    return true;
3361  }
3362  if (super == NULL) {
3363    ThrowLinkageError(klass.get(), "No superclass defined for class %s",
3364                      PrettyDescriptor(klass.get()).c_str());
3365    return false;
3366  }
3367  // Verify
3368  if (super->IsFinal() || super->IsInterface()) {
3369    ThrowIncompatibleClassChangeError(klass.get(), "Superclass %s of %s is %s",
3370                                      PrettyDescriptor(super).c_str(),
3371                                      PrettyDescriptor(klass.get()).c_str(),
3372                                      super->IsFinal() ? "declared final" : "an interface");
3373    return false;
3374  }
3375  if (!klass->CanAccess(super)) {
3376    ThrowIllegalAccessError(klass.get(), "Superclass %s is inaccessible to class %s",
3377                            PrettyDescriptor(super).c_str(),
3378                            PrettyDescriptor(klass.get()).c_str());
3379    return false;
3380  }
3381
3382  // Inherit kAccClassIsFinalizable from the superclass in case this class doesn't override finalize.
3383  if (super->IsFinalizable()) {
3384    klass->SetFinalizable();
3385  }
3386
3387  // Inherit reference flags (if any) from the superclass.
3388  int reference_flags = (super->GetAccessFlags() & kAccReferenceFlagsMask);
3389  if (reference_flags != 0) {
3390    klass->SetAccessFlags(klass->GetAccessFlags() | reference_flags);
3391  }
3392  // Disallow custom direct subclasses of java.lang.ref.Reference.
3393  if (init_done_ && super == GetClassRoot(kJavaLangRefReference)) {
3394    ThrowLinkageError(klass.get(),
3395                      "Class %s attempts to subclass java.lang.ref.Reference, which is not allowed",
3396                      PrettyDescriptor(klass.get()).c_str());
3397    return false;
3398  }
3399
3400  if (kIsDebugBuild) {
3401    // Ensure super classes are fully resolved prior to resolving fields..
3402    while (super != NULL) {
3403      CHECK(super->IsResolved());
3404      super = super->GetSuperClass();
3405    }
3406  }
3407  return true;
3408}
3409
3410// Populate the class vtable and itable. Compute return type indices.
3411bool ClassLinker::LinkMethods(SirtRef<mirror::Class>& klass,
3412                              mirror::ObjectArray<mirror::Class>* interfaces) {
3413  if (klass->IsInterface()) {
3414    // No vtable.
3415    size_t count = klass->NumVirtualMethods();
3416    if (!IsUint(16, count)) {
3417      ThrowClassFormatError(klass.get(), "Too many methods on interface: %zd", count);
3418      return false;
3419    }
3420    for (size_t i = 0; i < count; ++i) {
3421      klass->GetVirtualMethodDuringLinking(i)->SetMethodIndex(i);
3422    }
3423    // Link interface method tables
3424    return LinkInterfaceMethods(klass, interfaces);
3425  } else {
3426    // Link virtual and interface method tables
3427    return LinkVirtualMethods(klass) && LinkInterfaceMethods(klass, interfaces);
3428  }
3429  return true;
3430}
3431
3432bool ClassLinker::LinkVirtualMethods(SirtRef<mirror::Class>& klass) {
3433  Thread* self = Thread::Current();
3434  if (klass->HasSuperClass()) {
3435    uint32_t max_count = klass->NumVirtualMethods() + klass->GetSuperClass()->GetVTable()->GetLength();
3436    size_t actual_count = klass->GetSuperClass()->GetVTable()->GetLength();
3437    CHECK_LE(actual_count, max_count);
3438    // TODO: do not assign to the vtable field until it is fully constructed.
3439    SirtRef<mirror::ObjectArray<mirror::ArtMethod> >
3440      vtable(self, klass->GetSuperClass()->GetVTable()->CopyOf(self, max_count));
3441    if (UNLIKELY(vtable.get() == NULL)) {
3442      CHECK(self->IsExceptionPending());  // OOME.
3443      return false;
3444    }
3445    // See if any of our virtual methods override the superclass.
3446    MethodHelper local_mh(NULL, this);
3447    MethodHelper super_mh(NULL, this);
3448    for (size_t i = 0; i < klass->NumVirtualMethods(); ++i) {
3449      mirror::ArtMethod* local_method = klass->GetVirtualMethodDuringLinking(i);
3450      local_mh.ChangeMethod(local_method);
3451      size_t j = 0;
3452      for (; j < actual_count; ++j) {
3453        mirror::ArtMethod* super_method = vtable->Get(j);
3454        super_mh.ChangeMethod(super_method);
3455        if (local_mh.HasSameNameAndSignature(&super_mh)) {
3456          if (klass->CanAccessMember(super_method->GetDeclaringClass(), super_method->GetAccessFlags())) {
3457            if (super_method->IsFinal()) {
3458              ThrowLinkageError(klass.get(), "Method %s overrides final method in class %s",
3459                                PrettyMethod(local_method).c_str(),
3460                                super_mh.GetDeclaringClassDescriptor());
3461              return false;
3462            }
3463            vtable->Set(j, local_method);
3464            local_method->SetMethodIndex(j);
3465            break;
3466          } else {
3467            LOG(WARNING) << "Before Android 4.1, method " << PrettyMethod(local_method)
3468                         << " would have incorrectly overridden the package-private method in "
3469                         << PrettyDescriptor(super_mh.GetDeclaringClassDescriptor());
3470          }
3471        }
3472      }
3473      if (j == actual_count) {
3474        // Not overriding, append.
3475        vtable->Set(actual_count, local_method);
3476        local_method->SetMethodIndex(actual_count);
3477        actual_count += 1;
3478      }
3479    }
3480    if (!IsUint(16, actual_count)) {
3481      ThrowClassFormatError(klass.get(), "Too many methods defined on class: %zd", actual_count);
3482      return false;
3483    }
3484    // Shrink vtable if possible
3485    CHECK_LE(actual_count, max_count);
3486    if (actual_count < max_count) {
3487      vtable.reset(vtable->CopyOf(self, actual_count));
3488      if (UNLIKELY(vtable.get() == NULL)) {
3489        CHECK(self->IsExceptionPending());  // OOME.
3490        return false;
3491      }
3492    }
3493    klass->SetVTable(vtable.get());
3494  } else {
3495    CHECK(klass.get() == GetClassRoot(kJavaLangObject));
3496    uint32_t num_virtual_methods = klass->NumVirtualMethods();
3497    if (!IsUint(16, num_virtual_methods)) {
3498      ThrowClassFormatError(klass.get(), "Too many methods: %d", num_virtual_methods);
3499      return false;
3500    }
3501    SirtRef<mirror::ObjectArray<mirror::ArtMethod> >
3502        vtable(self, AllocArtMethodArray(self, num_virtual_methods));
3503    if (UNLIKELY(vtable.get() == NULL)) {
3504      CHECK(self->IsExceptionPending());  // OOME.
3505      return false;
3506    }
3507    for (size_t i = 0; i < num_virtual_methods; ++i) {
3508      mirror::ArtMethod* virtual_method = klass->GetVirtualMethodDuringLinking(i);
3509      vtable->Set(i, virtual_method);
3510      virtual_method->SetMethodIndex(i & 0xFFFF);
3511    }
3512    klass->SetVTable(vtable.get());
3513  }
3514  return true;
3515}
3516
3517bool ClassLinker::LinkInterfaceMethods(SirtRef<mirror::Class>& klass,
3518                                       mirror::ObjectArray<mirror::Class>* interfaces) {
3519  size_t super_ifcount;
3520  if (klass->HasSuperClass()) {
3521    super_ifcount = klass->GetSuperClass()->GetIfTableCount();
3522  } else {
3523    super_ifcount = 0;
3524  }
3525  size_t ifcount = super_ifcount;
3526  ClassHelper kh(klass.get(), this);
3527  uint32_t num_interfaces = interfaces == NULL ? kh.NumDirectInterfaces() : interfaces->GetLength();
3528  ifcount += num_interfaces;
3529  for (size_t i = 0; i < num_interfaces; i++) {
3530    mirror::Class* interface = interfaces == NULL ? kh.GetDirectInterface(i) : interfaces->Get(i);
3531    ifcount += interface->GetIfTableCount();
3532  }
3533  if (ifcount == 0) {
3534    // Class implements no interfaces.
3535    DCHECK_EQ(klass->GetIfTableCount(), 0);
3536    DCHECK(klass->GetIfTable() == NULL);
3537    return true;
3538  }
3539  if (ifcount == super_ifcount) {
3540    // Class implements same interfaces as parent, are any of these not marker interfaces?
3541    bool has_non_marker_interface = false;
3542    mirror::IfTable* super_iftable = klass->GetSuperClass()->GetIfTable();
3543    for (size_t i = 0; i < ifcount; ++i) {
3544      if (super_iftable->GetMethodArrayCount(i) > 0) {
3545        has_non_marker_interface = true;
3546        break;
3547      }
3548    }
3549    if (!has_non_marker_interface) {
3550      // Class just inherits marker interfaces from parent so recycle parent's iftable.
3551      klass->SetIfTable(super_iftable);
3552      return true;
3553    }
3554  }
3555  Thread* self = Thread::Current();
3556  SirtRef<mirror::IfTable> iftable(self, AllocIfTable(self, ifcount));
3557  if (UNLIKELY(iftable.get() == NULL)) {
3558    CHECK(self->IsExceptionPending());  // OOME.
3559    return false;
3560  }
3561  if (super_ifcount != 0) {
3562    mirror::IfTable* super_iftable = klass->GetSuperClass()->GetIfTable();
3563    for (size_t i = 0; i < super_ifcount; i++) {
3564      mirror::Class* super_interface = super_iftable->GetInterface(i);
3565      iftable->SetInterface(i, super_interface);
3566    }
3567  }
3568  // Flatten the interface inheritance hierarchy.
3569  size_t idx = super_ifcount;
3570  for (size_t i = 0; i < num_interfaces; i++) {
3571    mirror::Class* interface = interfaces == NULL ? kh.GetDirectInterface(i) : interfaces->Get(i);
3572    DCHECK(interface != NULL);
3573    if (!interface->IsInterface()) {
3574      ClassHelper ih(interface);
3575      ThrowIncompatibleClassChangeError(klass.get(), "Class %s implements non-interface class %s",
3576                                        PrettyDescriptor(klass.get()).c_str(),
3577                                        PrettyDescriptor(ih.GetDescriptor()).c_str());
3578      return false;
3579    }
3580    // Check if interface is already in iftable
3581    bool duplicate = false;
3582    for (size_t j = 0; j < idx; j++) {
3583      mirror::Class* existing_interface = iftable->GetInterface(j);
3584      if (existing_interface == interface) {
3585        duplicate = true;
3586        break;
3587      }
3588    }
3589    if (!duplicate) {
3590      // Add this non-duplicate interface.
3591      iftable->SetInterface(idx++, interface);
3592      // Add this interface's non-duplicate super-interfaces.
3593      for (int32_t j = 0; j < interface->GetIfTableCount(); j++) {
3594        mirror::Class* super_interface = interface->GetIfTable()->GetInterface(j);
3595        bool super_duplicate = false;
3596        for (size_t k = 0; k < idx; k++) {
3597          mirror::Class* existing_interface = iftable->GetInterface(k);
3598          if (existing_interface == super_interface) {
3599            super_duplicate = true;
3600            break;
3601          }
3602        }
3603        if (!super_duplicate) {
3604          iftable->SetInterface(idx++, super_interface);
3605        }
3606      }
3607    }
3608  }
3609  // Shrink iftable in case duplicates were found
3610  if (idx < ifcount) {
3611    iftable.reset(down_cast<mirror::IfTable*>(iftable->CopyOf(self, idx * mirror::IfTable::kMax)));
3612    if (UNLIKELY(iftable.get() == NULL)) {
3613      CHECK(self->IsExceptionPending());  // OOME.
3614      return false;
3615    }
3616    ifcount = idx;
3617  } else {
3618    CHECK_EQ(idx, ifcount);
3619  }
3620  klass->SetIfTable(iftable.get());
3621
3622  // If we're an interface, we don't need the vtable pointers, so we're done.
3623  if (klass->IsInterface()) {
3624    return true;
3625  }
3626  std::vector<mirror::ArtMethod*> miranda_list;
3627  MethodHelper vtable_mh(NULL, this);
3628  MethodHelper interface_mh(NULL, this);
3629  for (size_t i = 0; i < ifcount; ++i) {
3630    mirror::Class* interface = iftable->GetInterface(i);
3631    size_t num_methods = interface->NumVirtualMethods();
3632    if (num_methods > 0) {
3633      mirror::ObjectArray<mirror::ArtMethod>* method_array =
3634          AllocArtMethodArray(self, num_methods);
3635      if (UNLIKELY(method_array == NULL)) {
3636        CHECK(self->IsExceptionPending());  // OOME.
3637        return false;
3638      }
3639      iftable->SetMethodArray(i, method_array);
3640      mirror::ObjectArray<mirror::ArtMethod>* vtable = klass->GetVTableDuringLinking();
3641      for (size_t j = 0; j < num_methods; ++j) {
3642        mirror::ArtMethod* interface_method = interface->GetVirtualMethod(j);
3643        interface_mh.ChangeMethod(interface_method);
3644        int32_t k;
3645        // For each method listed in the interface's method list, find the
3646        // matching method in our class's method list.  We want to favor the
3647        // subclass over the superclass, which just requires walking
3648        // back from the end of the vtable.  (This only matters if the
3649        // superclass defines a private method and this class redefines
3650        // it -- otherwise it would use the same vtable slot.  In .dex files
3651        // those don't end up in the virtual method table, so it shouldn't
3652        // matter which direction we go.  We walk it backward anyway.)
3653        for (k = vtable->GetLength() - 1; k >= 0; --k) {
3654          mirror::ArtMethod* vtable_method = vtable->Get(k);
3655          vtable_mh.ChangeMethod(vtable_method);
3656          if (interface_mh.HasSameNameAndSignature(&vtable_mh)) {
3657            if (!vtable_method->IsAbstract() && !vtable_method->IsPublic()) {
3658              ThrowIllegalAccessError(klass.get(),
3659                                      "Method '%s' implementing interface method '%s' is not public",
3660                                      PrettyMethod(vtable_method).c_str(),
3661                                      PrettyMethod(interface_method).c_str());
3662              return false;
3663            }
3664            method_array->Set(j, vtable_method);
3665            break;
3666          }
3667        }
3668        if (k < 0) {
3669          SirtRef<mirror::ArtMethod> miranda_method(self, NULL);
3670          for (size_t mir = 0; mir < miranda_list.size(); mir++) {
3671            mirror::ArtMethod* mir_method = miranda_list[mir];
3672            vtable_mh.ChangeMethod(mir_method);
3673            if (interface_mh.HasSameNameAndSignature(&vtable_mh)) {
3674              miranda_method.reset(miranda_list[mir]);
3675              break;
3676            }
3677          }
3678          if (miranda_method.get() == NULL) {
3679            // Point the interface table at a phantom slot.
3680            miranda_method.reset(down_cast<mirror::ArtMethod*>(interface_method->Clone(self)));
3681            if (UNLIKELY(miranda_method.get() == NULL)) {
3682              CHECK(self->IsExceptionPending());  // OOME.
3683              return false;
3684            }
3685#ifdef MOVING_GARBAGE_COLLECTOR
3686            // TODO: If a methods move then the miranda_list may hold stale references.
3687            UNIMPLEMENTED(FATAL);
3688#endif
3689            miranda_list.push_back(miranda_method.get());
3690          }
3691          method_array->Set(j, miranda_method.get());
3692        }
3693      }
3694    }
3695  }
3696  if (!miranda_list.empty()) {
3697    int old_method_count = klass->NumVirtualMethods();
3698    int new_method_count = old_method_count + miranda_list.size();
3699    mirror::ObjectArray<mirror::ArtMethod>* virtuals;
3700    if (old_method_count == 0) {
3701      virtuals = AllocArtMethodArray(self, new_method_count);
3702    } else {
3703      virtuals = klass->GetVirtualMethods()->CopyOf(self, new_method_count);
3704    }
3705    if (UNLIKELY(virtuals == NULL)) {
3706      CHECK(self->IsExceptionPending());  // OOME.
3707      return false;
3708    }
3709    klass->SetVirtualMethods(virtuals);
3710
3711    SirtRef<mirror::ObjectArray<mirror::ArtMethod> >
3712        vtable(self, klass->GetVTableDuringLinking());
3713    CHECK(vtable.get() != NULL);
3714    int old_vtable_count = vtable->GetLength();
3715    int new_vtable_count = old_vtable_count + miranda_list.size();
3716    vtable.reset(vtable->CopyOf(self, new_vtable_count));
3717    if (UNLIKELY(vtable.get() == NULL)) {
3718      CHECK(self->IsExceptionPending());  // OOME.
3719      return false;
3720    }
3721    for (size_t i = 0; i < miranda_list.size(); ++i) {
3722      mirror::ArtMethod* method = miranda_list[i];
3723      // Leave the declaring class alone as type indices are relative to it
3724      method->SetAccessFlags(method->GetAccessFlags() | kAccMiranda);
3725      method->SetMethodIndex(0xFFFF & (old_vtable_count + i));
3726      klass->SetVirtualMethod(old_method_count + i, method);
3727      vtable->Set(old_vtable_count + i, method);
3728    }
3729    // TODO: do not assign to the vtable field until it is fully constructed.
3730    klass->SetVTable(vtable.get());
3731  }
3732
3733  mirror::ObjectArray<mirror::ArtMethod>* vtable = klass->GetVTableDuringLinking();
3734  for (int i = 0; i < vtable->GetLength(); ++i) {
3735    CHECK(vtable->Get(i) != NULL);
3736  }
3737
3738//  klass->DumpClass(std::cerr, Class::kDumpClassFullDetail);
3739
3740  return true;
3741}
3742
3743bool ClassLinker::LinkInstanceFields(SirtRef<mirror::Class>& klass) {
3744  CHECK(klass.get() != NULL);
3745  return LinkFields(klass, false);
3746}
3747
3748bool ClassLinker::LinkStaticFields(SirtRef<mirror::Class>& klass) {
3749  CHECK(klass.get() != NULL);
3750  size_t allocated_class_size = klass->GetClassSize();
3751  bool success = LinkFields(klass, true);
3752  CHECK_EQ(allocated_class_size, klass->GetClassSize());
3753  return success;
3754}
3755
3756struct LinkFieldsComparator {
3757  explicit LinkFieldsComparator(FieldHelper* fh)
3758      SHARED_LOCKS_REQUIRED(Locks::mutator_lock_)
3759      : fh_(fh) {}
3760  // No thread safety analysis as will be called from STL. Checked lock held in constructor.
3761  bool operator()(const mirror::ArtField* field1, const mirror::ArtField* field2)
3762      NO_THREAD_SAFETY_ANALYSIS {
3763    // First come reference fields, then 64-bit, and finally 32-bit
3764    fh_->ChangeField(field1);
3765    Primitive::Type type1 = fh_->GetTypeAsPrimitiveType();
3766    fh_->ChangeField(field2);
3767    Primitive::Type type2 = fh_->GetTypeAsPrimitiveType();
3768    bool isPrimitive1 = type1 != Primitive::kPrimNot;
3769    bool isPrimitive2 = type2 != Primitive::kPrimNot;
3770    bool is64bit1 = isPrimitive1 && (type1 == Primitive::kPrimLong || type1 == Primitive::kPrimDouble);
3771    bool is64bit2 = isPrimitive2 && (type2 == Primitive::kPrimLong || type2 == Primitive::kPrimDouble);
3772    int order1 = (!isPrimitive1 ? 0 : (is64bit1 ? 1 : 2));
3773    int order2 = (!isPrimitive2 ? 0 : (is64bit2 ? 1 : 2));
3774    if (order1 != order2) {
3775      return order1 < order2;
3776    }
3777
3778    // same basic group? then sort by string.
3779    fh_->ChangeField(field1);
3780    const char* name1 = fh_->GetName();
3781    fh_->ChangeField(field2);
3782    const char* name2 = fh_->GetName();
3783    return strcmp(name1, name2) < 0;
3784  }
3785
3786  FieldHelper* fh_;
3787};
3788
3789bool ClassLinker::LinkFields(SirtRef<mirror::Class>& klass, bool is_static) {
3790  size_t num_fields =
3791      is_static ? klass->NumStaticFields() : klass->NumInstanceFields();
3792
3793  mirror::ObjectArray<mirror::ArtField>* fields =
3794      is_static ? klass->GetSFields() : klass->GetIFields();
3795
3796  // Initialize size and field_offset
3797  size_t size;
3798  MemberOffset field_offset(0);
3799  if (is_static) {
3800    size = klass->GetClassSize();
3801    field_offset = mirror::Class::FieldsOffset();
3802  } else {
3803    mirror::Class* super_class = klass->GetSuperClass();
3804    if (super_class != NULL) {
3805      CHECK(super_class->IsResolved());
3806      field_offset = MemberOffset(super_class->GetObjectSize());
3807    }
3808    size = field_offset.Uint32Value();
3809  }
3810
3811  CHECK_EQ(num_fields == 0, fields == NULL);
3812
3813  // we want a relatively stable order so that adding new fields
3814  // minimizes disruption of C++ version such as Class and Method.
3815  std::deque<mirror::ArtField*> grouped_and_sorted_fields;
3816  for (size_t i = 0; i < num_fields; i++) {
3817    mirror::ArtField* f = fields->Get(i);
3818    CHECK(f != NULL);
3819    grouped_and_sorted_fields.push_back(f);
3820  }
3821  FieldHelper fh(NULL, this);
3822  std::sort(grouped_and_sorted_fields.begin(),
3823            grouped_and_sorted_fields.end(),
3824            LinkFieldsComparator(&fh));
3825
3826  // References should be at the front.
3827  size_t current_field = 0;
3828  size_t num_reference_fields = 0;
3829  for (; current_field < num_fields; current_field++) {
3830    mirror::ArtField* field = grouped_and_sorted_fields.front();
3831    fh.ChangeField(field);
3832    Primitive::Type type = fh.GetTypeAsPrimitiveType();
3833    bool isPrimitive = type != Primitive::kPrimNot;
3834    if (isPrimitive) {
3835      break;  // past last reference, move on to the next phase
3836    }
3837    grouped_and_sorted_fields.pop_front();
3838    num_reference_fields++;
3839    fields->Set(current_field, field);
3840    field->SetOffset(field_offset);
3841    field_offset = MemberOffset(field_offset.Uint32Value() + sizeof(uint32_t));
3842  }
3843
3844  // Now we want to pack all of the double-wide fields together.  If
3845  // we're not aligned, though, we want to shuffle one 32-bit field
3846  // into place.  If we can't find one, we'll have to pad it.
3847  if (current_field != num_fields && !IsAligned<8>(field_offset.Uint32Value())) {
3848    for (size_t i = 0; i < grouped_and_sorted_fields.size(); i++) {
3849      mirror::ArtField* field = grouped_and_sorted_fields[i];
3850      fh.ChangeField(field);
3851      Primitive::Type type = fh.GetTypeAsPrimitiveType();
3852      CHECK(type != Primitive::kPrimNot);  // should only be working on primitive types
3853      if (type == Primitive::kPrimLong || type == Primitive::kPrimDouble) {
3854        continue;
3855      }
3856      fields->Set(current_field++, field);
3857      field->SetOffset(field_offset);
3858      // drop the consumed field
3859      grouped_and_sorted_fields.erase(grouped_and_sorted_fields.begin() + i);
3860      break;
3861    }
3862    // whether we found a 32-bit field for padding or not, we advance
3863    field_offset = MemberOffset(field_offset.Uint32Value() + sizeof(uint32_t));
3864  }
3865
3866  // Alignment is good, shuffle any double-wide fields forward, and
3867  // finish assigning field offsets to all fields.
3868  DCHECK(current_field == num_fields || IsAligned<8>(field_offset.Uint32Value()));
3869  while (!grouped_and_sorted_fields.empty()) {
3870    mirror::ArtField* field = grouped_and_sorted_fields.front();
3871    grouped_and_sorted_fields.pop_front();
3872    fh.ChangeField(field);
3873    Primitive::Type type = fh.GetTypeAsPrimitiveType();
3874    CHECK(type != Primitive::kPrimNot);  // should only be working on primitive types
3875    fields->Set(current_field, field);
3876    field->SetOffset(field_offset);
3877    field_offset = MemberOffset(field_offset.Uint32Value() +
3878                                ((type == Primitive::kPrimLong || type == Primitive::kPrimDouble)
3879                                 ? sizeof(uint64_t)
3880                                 : sizeof(uint32_t)));
3881    current_field++;
3882  }
3883
3884  // We lie to the GC about the java.lang.ref.Reference.referent field, so it doesn't scan it.
3885  if (!is_static &&
3886      (strcmp("Ljava/lang/ref/Reference;", ClassHelper(klass.get(), this).GetDescriptor()) == 0)) {
3887    // We know there are no non-reference fields in the Reference classes, and we know
3888    // that 'referent' is alphabetically last, so this is easy...
3889    CHECK_EQ(num_reference_fields, num_fields);
3890    fh.ChangeField(fields->Get(num_fields - 1));
3891    CHECK_STREQ(fh.GetName(), "referent");
3892    --num_reference_fields;
3893  }
3894
3895  if (kIsDebugBuild) {
3896    // Make sure that all reference fields appear before
3897    // non-reference fields, and all double-wide fields are aligned.
3898    bool seen_non_ref = false;
3899    for (size_t i = 0; i < num_fields; i++) {
3900      mirror::ArtField* field = fields->Get(i);
3901      if (false) {  // enable to debug field layout
3902        LOG(INFO) << "LinkFields: " << (is_static ? "static" : "instance")
3903                    << " class=" << PrettyClass(klass.get())
3904                    << " field=" << PrettyField(field)
3905                    << " offset=" << field->GetField32(MemberOffset(mirror::ArtField::OffsetOffset()),
3906                                                       false);
3907      }
3908      fh.ChangeField(field);
3909      Primitive::Type type = fh.GetTypeAsPrimitiveType();
3910      bool is_primitive = type != Primitive::kPrimNot;
3911      if ((strcmp("Ljava/lang/ref/Reference;", ClassHelper(klass.get(), this).GetDescriptor()) == 0)
3912          && (strcmp("referent", fh.GetName()) == 0)) {
3913        is_primitive = true;  // We lied above, so we have to expect a lie here.
3914      }
3915      if (is_primitive) {
3916        if (!seen_non_ref) {
3917          seen_non_ref = true;
3918          DCHECK_EQ(num_reference_fields, i);
3919        }
3920      } else {
3921        DCHECK(!seen_non_ref);
3922      }
3923    }
3924    if (!seen_non_ref) {
3925      DCHECK_EQ(num_fields, num_reference_fields);
3926    }
3927  }
3928  size = field_offset.Uint32Value();
3929  // Update klass
3930  if (is_static) {
3931    klass->SetNumReferenceStaticFields(num_reference_fields);
3932    klass->SetClassSize(size);
3933  } else {
3934    klass->SetNumReferenceInstanceFields(num_reference_fields);
3935    if (!klass->IsVariableSize()) {
3936      DCHECK_GE(size, sizeof(mirror::Object)) << ClassHelper(klass.get(), this).GetDescriptor();
3937      size_t previous_size = klass->GetObjectSize();
3938      if (previous_size != 0) {
3939        // Make sure that we didn't originally have an incorrect size.
3940        CHECK_EQ(previous_size, size);
3941      }
3942      klass->SetObjectSize(size);
3943    }
3944  }
3945  return true;
3946}
3947
3948//  Set the bitmap of reference offsets, refOffsets, from the ifields
3949//  list.
3950void ClassLinker::CreateReferenceInstanceOffsets(SirtRef<mirror::Class>& klass) {
3951  uint32_t reference_offsets = 0;
3952  mirror::Class* super_class = klass->GetSuperClass();
3953  if (super_class != NULL) {
3954    reference_offsets = super_class->GetReferenceInstanceOffsets();
3955    // If our superclass overflowed, we don't stand a chance.
3956    if (reference_offsets == CLASS_WALK_SUPER) {
3957      klass->SetReferenceInstanceOffsets(reference_offsets);
3958      return;
3959    }
3960  }
3961  CreateReferenceOffsets(klass, false, reference_offsets);
3962}
3963
3964void ClassLinker::CreateReferenceStaticOffsets(SirtRef<mirror::Class>& klass) {
3965  CreateReferenceOffsets(klass, true, 0);
3966}
3967
3968void ClassLinker::CreateReferenceOffsets(SirtRef<mirror::Class>& klass, bool is_static,
3969                                         uint32_t reference_offsets) {
3970  size_t num_reference_fields =
3971      is_static ? klass->NumReferenceStaticFieldsDuringLinking()
3972                : klass->NumReferenceInstanceFieldsDuringLinking();
3973  const mirror::ObjectArray<mirror::ArtField>* fields =
3974      is_static ? klass->GetSFields() : klass->GetIFields();
3975  // All of the fields that contain object references are guaranteed
3976  // to be at the beginning of the fields list.
3977  for (size_t i = 0; i < num_reference_fields; ++i) {
3978    // Note that byte_offset is the offset from the beginning of
3979    // object, not the offset into instance data
3980    const mirror::ArtField* field = fields->Get(i);
3981    MemberOffset byte_offset = field->GetOffsetDuringLinking();
3982    CHECK_EQ(byte_offset.Uint32Value() & (CLASS_OFFSET_ALIGNMENT - 1), 0U);
3983    if (CLASS_CAN_ENCODE_OFFSET(byte_offset.Uint32Value())) {
3984      uint32_t new_bit = CLASS_BIT_FROM_OFFSET(byte_offset.Uint32Value());
3985      CHECK_NE(new_bit, 0U);
3986      reference_offsets |= new_bit;
3987    } else {
3988      reference_offsets = CLASS_WALK_SUPER;
3989      break;
3990    }
3991  }
3992  // Update fields in klass
3993  if (is_static) {
3994    klass->SetReferenceStaticOffsets(reference_offsets);
3995  } else {
3996    klass->SetReferenceInstanceOffsets(reference_offsets);
3997  }
3998}
3999
4000mirror::String* ClassLinker::ResolveString(const DexFile& dex_file,
4001                                           uint32_t string_idx, mirror::DexCache* dex_cache) {
4002  DCHECK(dex_cache != NULL);
4003  mirror::String* resolved = dex_cache->GetResolvedString(string_idx);
4004  if (resolved != NULL) {
4005    return resolved;
4006  }
4007  uint32_t utf16_length;
4008  const char* utf8_data = dex_file.StringDataAndUtf16LengthByIdx(string_idx, &utf16_length);
4009  mirror::String* string = intern_table_->InternStrong(utf16_length, utf8_data);
4010  dex_cache->SetResolvedString(string_idx, string);
4011  return string;
4012}
4013
4014mirror::Class* ClassLinker::ResolveType(const DexFile& dex_file,
4015                                        uint16_t type_idx,
4016                                        mirror::DexCache* dex_cache,
4017                                        mirror::ClassLoader* class_loader) {
4018  DCHECK(dex_cache != NULL);
4019  mirror::Class* resolved = dex_cache->GetResolvedType(type_idx);
4020  if (resolved == NULL) {
4021    const char* descriptor = dex_file.StringByTypeIdx(type_idx);
4022    resolved = FindClass(descriptor, class_loader);
4023    if (resolved != NULL) {
4024      // TODO: we used to throw here if resolved's class loader was not the
4025      //       boot class loader. This was to permit different classes with the
4026      //       same name to be loaded simultaneously by different loaders
4027      dex_cache->SetResolvedType(type_idx, resolved);
4028    } else {
4029      Thread* self = Thread::Current();
4030      CHECK(self->IsExceptionPending())
4031          << "Expected pending exception for failed resolution of: " << descriptor;
4032      // Convert a ClassNotFoundException to a NoClassDefFoundError.
4033      SirtRef<mirror::Throwable> cause(self, self->GetException(NULL));
4034      if (cause->InstanceOf(GetClassRoot(kJavaLangClassNotFoundException))) {
4035        Thread::Current()->ClearException();
4036        ThrowNoClassDefFoundError("Failed resolution of: %s", descriptor);
4037        self->GetException(NULL)->SetCause(cause.get());
4038      }
4039    }
4040  }
4041  DCHECK((resolved == NULL) || resolved->IsResolved() || resolved->IsErroneous())
4042          << PrettyDescriptor(resolved) << " " << resolved->GetStatus();
4043  return resolved;
4044}
4045
4046mirror::ArtMethod* ClassLinker::ResolveMethod(const DexFile& dex_file,
4047                                              uint32_t method_idx,
4048                                              mirror::DexCache* dex_cache,
4049                                              mirror::ClassLoader* class_loader,
4050                                              const mirror::ArtMethod* referrer,
4051                                              InvokeType type) {
4052  DCHECK(dex_cache != NULL);
4053  // Check for hit in the dex cache.
4054  mirror::ArtMethod* resolved = dex_cache->GetResolvedMethod(method_idx);
4055  if (resolved != NULL && !resolved->IsRuntimeMethod()) {
4056    return resolved;
4057  }
4058  // Fail, get the declaring class.
4059  const DexFile::MethodId& method_id = dex_file.GetMethodId(method_idx);
4060  mirror::Class* klass = ResolveType(dex_file, method_id.class_idx_, dex_cache, class_loader);
4061  if (klass == NULL) {
4062    DCHECK(Thread::Current()->IsExceptionPending());
4063    return NULL;
4064  }
4065  // Scan using method_idx, this saves string compares but will only hit for matching dex
4066  // caches/files.
4067  switch (type) {
4068    case kDirect:  // Fall-through.
4069    case kStatic:
4070      resolved = klass->FindDirectMethod(dex_cache, method_idx);
4071      break;
4072    case kInterface:
4073      resolved = klass->FindInterfaceMethod(dex_cache, method_idx);
4074      DCHECK(resolved == NULL || resolved->GetDeclaringClass()->IsInterface());
4075      break;
4076    case kSuper:  // Fall-through.
4077    case kVirtual:
4078      resolved = klass->FindVirtualMethod(dex_cache, method_idx);
4079      break;
4080    default:
4081      LOG(FATAL) << "Unreachable - invocation type: " << type;
4082  }
4083  if (resolved == NULL) {
4084    // Search by name, which works across dex files.
4085    const char* name = dex_file.StringDataByIdx(method_id.name_idx_);
4086    const Signature signature = dex_file.GetMethodSignature(method_id);
4087    switch (type) {
4088      case kDirect:  // Fall-through.
4089      case kStatic:
4090        resolved = klass->FindDirectMethod(name, signature);
4091        break;
4092      case kInterface:
4093        resolved = klass->FindInterfaceMethod(name, signature);
4094        DCHECK(resolved == NULL || resolved->GetDeclaringClass()->IsInterface());
4095        break;
4096      case kSuper:  // Fall-through.
4097      case kVirtual:
4098        resolved = klass->FindVirtualMethod(name, signature);
4099        break;
4100    }
4101  }
4102  if (resolved != NULL) {
4103    // We found a method, check for incompatible class changes.
4104    if (resolved->CheckIncompatibleClassChange(type)) {
4105      resolved = NULL;
4106    }
4107  }
4108  if (resolved != NULL) {
4109    // Be a good citizen and update the dex cache to speed subsequent calls.
4110    dex_cache->SetResolvedMethod(method_idx, resolved);
4111    return resolved;
4112  } else {
4113    // We failed to find the method which means either an access error, an incompatible class
4114    // change, or no such method. First try to find the method among direct and virtual methods.
4115    const char* name = dex_file.StringDataByIdx(method_id.name_idx_);
4116    const Signature signature = dex_file.GetMethodSignature(method_id);
4117    switch (type) {
4118      case kDirect:
4119      case kStatic:
4120        resolved = klass->FindVirtualMethod(name, signature);
4121        break;
4122      case kInterface:
4123      case kVirtual:
4124      case kSuper:
4125        resolved = klass->FindDirectMethod(name, signature);
4126        break;
4127    }
4128
4129    // If we found something, check that it can be accessed by the referrer.
4130    if (resolved != NULL && referrer != NULL) {
4131      mirror::Class* methods_class = resolved->GetDeclaringClass();
4132      mirror::Class* referring_class = referrer->GetDeclaringClass();
4133      if (!referring_class->CanAccess(methods_class)) {
4134        ThrowIllegalAccessErrorClassForMethodDispatch(referring_class, methods_class,
4135                                                      referrer, resolved, type);
4136        return NULL;
4137      } else if (!referring_class->CanAccessMember(methods_class,
4138                                                   resolved->GetAccessFlags())) {
4139        ThrowIllegalAccessErrorMethod(referring_class, resolved);
4140        return NULL;
4141      }
4142    }
4143
4144    // Otherwise, throw an IncompatibleClassChangeError if we found something, and check interface
4145    // methods and throw if we find the method there. If we find nothing, throw a NoSuchMethodError.
4146    switch (type) {
4147      case kDirect:
4148      case kStatic:
4149        if (resolved != NULL) {
4150          ThrowIncompatibleClassChangeError(type, kVirtual, resolved, referrer);
4151        } else {
4152          resolved = klass->FindInterfaceMethod(name, signature);
4153          if (resolved != NULL) {
4154            ThrowIncompatibleClassChangeError(type, kInterface, resolved, referrer);
4155          } else {
4156            ThrowNoSuchMethodError(type, klass, name, signature);
4157          }
4158        }
4159        break;
4160      case kInterface:
4161        if (resolved != NULL) {
4162          ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer);
4163        } else {
4164          resolved = klass->FindVirtualMethod(name, signature);
4165          if (resolved != NULL) {
4166            ThrowIncompatibleClassChangeError(type, kVirtual, resolved, referrer);
4167          } else {
4168            ThrowNoSuchMethodError(type, klass, name, signature);
4169          }
4170        }
4171        break;
4172      case kSuper:
4173        ThrowNoSuchMethodError(type, klass, name, signature);
4174        break;
4175      case kVirtual:
4176        if (resolved != NULL) {
4177          ThrowIncompatibleClassChangeError(type, kDirect, resolved, referrer);
4178        } else {
4179          resolved = klass->FindInterfaceMethod(name, signature);
4180          if (resolved != NULL) {
4181            ThrowIncompatibleClassChangeError(type, kInterface, resolved, referrer);
4182          } else {
4183            ThrowNoSuchMethodError(type, klass, name, signature);
4184          }
4185        }
4186        break;
4187    }
4188    DCHECK(Thread::Current()->IsExceptionPending());
4189    return NULL;
4190  }
4191}
4192
4193mirror::ArtField* ClassLinker::ResolveField(const DexFile& dex_file,
4194                                            uint32_t field_idx,
4195                                            mirror::DexCache* dex_cache,
4196                                            mirror::ClassLoader* class_loader,
4197                                            bool is_static) {
4198  DCHECK(dex_cache != NULL);
4199  mirror::ArtField* resolved = dex_cache->GetResolvedField(field_idx);
4200  if (resolved != NULL) {
4201    return resolved;
4202  }
4203  const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx);
4204  mirror::Class* klass = ResolveType(dex_file, field_id.class_idx_, dex_cache, class_loader);
4205  if (klass == NULL) {
4206    DCHECK(Thread::Current()->IsExceptionPending());
4207    return NULL;
4208  }
4209
4210  if (is_static) {
4211    resolved = klass->FindStaticField(dex_cache, field_idx);
4212  } else {
4213    resolved = klass->FindInstanceField(dex_cache, field_idx);
4214  }
4215
4216  if (resolved == NULL) {
4217    const char* name = dex_file.GetFieldName(field_id);
4218    const char* type = dex_file.GetFieldTypeDescriptor(field_id);
4219    if (is_static) {
4220      resolved = klass->FindStaticField(name, type);
4221    } else {
4222      resolved = klass->FindInstanceField(name, type);
4223    }
4224    if (resolved == NULL) {
4225      ThrowNoSuchFieldError(is_static ? "static " : "instance ", klass, type, name);
4226      return NULL;
4227    }
4228  }
4229  dex_cache->SetResolvedField(field_idx, resolved);
4230  return resolved;
4231}
4232
4233mirror::ArtField* ClassLinker::ResolveFieldJLS(const DexFile& dex_file,
4234                                               uint32_t field_idx,
4235                                               mirror::DexCache* dex_cache,
4236                                               mirror::ClassLoader* class_loader) {
4237  DCHECK(dex_cache != NULL);
4238  mirror::ArtField* resolved = dex_cache->GetResolvedField(field_idx);
4239  if (resolved != NULL) {
4240    return resolved;
4241  }
4242  const DexFile::FieldId& field_id = dex_file.GetFieldId(field_idx);
4243  mirror::Class* klass = ResolveType(dex_file, field_id.class_idx_, dex_cache, class_loader);
4244  if (klass == NULL) {
4245    DCHECK(Thread::Current()->IsExceptionPending());
4246    return NULL;
4247  }
4248
4249  StringPiece name(dex_file.StringDataByIdx(field_id.name_idx_));
4250  StringPiece type(dex_file.StringDataByIdx(
4251      dex_file.GetTypeId(field_id.type_idx_).descriptor_idx_));
4252  resolved = klass->FindField(name, type);
4253  if (resolved != NULL) {
4254    dex_cache->SetResolvedField(field_idx, resolved);
4255  } else {
4256    ThrowNoSuchFieldError("", klass, type, name);
4257  }
4258  return resolved;
4259}
4260
4261const char* ClassLinker::MethodShorty(uint32_t method_idx, mirror::ArtMethod* referrer,
4262                                      uint32_t* length) {
4263  mirror::Class* declaring_class = referrer->GetDeclaringClass();
4264  mirror::DexCache* dex_cache = declaring_class->GetDexCache();
4265  const DexFile& dex_file = *dex_cache->GetDexFile();
4266  const DexFile::MethodId& method_id = dex_file.GetMethodId(method_idx);
4267  return dex_file.GetMethodShorty(method_id, length);
4268}
4269
4270void ClassLinker::DumpAllClasses(int flags) {
4271  if (dex_cache_image_class_lookup_required_) {
4272    MoveImageClassesToClassTable();
4273  }
4274  // TODO: at the time this was written, it wasn't safe to call PrettyField with the ClassLinker
4275  // lock held, because it might need to resolve a field's type, which would try to take the lock.
4276  std::vector<mirror::Class*> all_classes;
4277  {
4278    ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_);
4279    for (const std::pair<size_t, mirror::Class*>& it : class_table_) {
4280      all_classes.push_back(it.second);
4281    }
4282  }
4283
4284  for (size_t i = 0; i < all_classes.size(); ++i) {
4285    all_classes[i]->DumpClass(std::cerr, flags);
4286  }
4287}
4288
4289void ClassLinker::DumpForSigQuit(std::ostream& os) {
4290  if (dex_cache_image_class_lookup_required_) {
4291    MoveImageClassesToClassTable();
4292  }
4293  ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_);
4294  os << "Loaded classes: " << class_table_.size() << " allocated classes\n";
4295}
4296
4297size_t ClassLinker::NumLoadedClasses() {
4298  if (dex_cache_image_class_lookup_required_) {
4299    MoveImageClassesToClassTable();
4300  }
4301  ReaderMutexLock mu(Thread::Current(), *Locks::classlinker_classes_lock_);
4302  return class_table_.size();
4303}
4304
4305pid_t ClassLinker::GetClassesLockOwner() {
4306  return Locks::classlinker_classes_lock_->GetExclusiveOwnerTid();
4307}
4308
4309pid_t ClassLinker::GetDexLockOwner() {
4310  return dex_lock_.GetExclusiveOwnerTid();
4311}
4312
4313void ClassLinker::SetClassRoot(ClassRoot class_root, mirror::Class* klass) {
4314  DCHECK(!init_done_);
4315
4316  DCHECK(klass != NULL);
4317  DCHECK(klass->GetClassLoader() == NULL);
4318
4319  DCHECK(class_roots_ != NULL);
4320  DCHECK(class_roots_->Get(class_root) == NULL);
4321  class_roots_->Set(class_root, klass);
4322}
4323
4324}  // namespace art
4325