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 "art_method.h"
18 
19 #include <cstddef>
20 
21 #include "android-base/stringprintf.h"
22 
23 #include "arch/context.h"
24 #include "art_method-inl.h"
25 #include "base/stringpiece.h"
26 #include "class_linker-inl.h"
27 #include "debugger.h"
28 #include "dex/descriptors_names.h"
29 #include "dex/dex_file-inl.h"
30 #include "dex/dex_file_exception_helpers.h"
31 #include "dex/dex_instruction.h"
32 #include "entrypoints/runtime_asm_entrypoints.h"
33 #include "gc/accounting/card_table-inl.h"
34 #include "interpreter/interpreter.h"
35 #include "jit/jit.h"
36 #include "jit/jit_code_cache.h"
37 #include "jit/profiling_info.h"
38 #include "jni_internal.h"
39 #include "mirror/class-inl.h"
40 #include "mirror/class_ext.h"
41 #include "mirror/executable.h"
42 #include "mirror/object-inl.h"
43 #include "mirror/object_array-inl.h"
44 #include "mirror/string.h"
45 #include "oat_file-inl.h"
46 #include "quicken_info.h"
47 #include "runtime_callbacks.h"
48 #include "scoped_thread_state_change-inl.h"
49 #include "vdex_file.h"
50 #include "well_known_classes.h"
51 
52 namespace art {
53 
54 using android::base::StringPrintf;
55 
56 extern "C" void art_quick_invoke_stub(ArtMethod*, uint32_t*, uint32_t, Thread*, JValue*,
57                                       const char*);
58 extern "C" void art_quick_invoke_static_stub(ArtMethod*, uint32_t*, uint32_t, Thread*, JValue*,
59                                              const char*);
60 
61 DEFINE_RUNTIME_DEBUG_FLAG(ArtMethod, kCheckDeclaringClassState);
62 
63 // Enforce that we he have the right index for runtime methods.
64 static_assert(ArtMethod::kRuntimeMethodDexMethodIndex == dex::kDexNoIndex,
65               "Wrong runtime-method dex method index");
66 
GetCanonicalMethod(PointerSize pointer_size)67 ArtMethod* ArtMethod::GetCanonicalMethod(PointerSize pointer_size) {
68   if (LIKELY(!IsDefault())) {
69     return this;
70   } else {
71     mirror::Class* declaring_class = GetDeclaringClass();
72     DCHECK(declaring_class->IsInterface());
73     ArtMethod* ret = declaring_class->FindInterfaceMethod(declaring_class->GetDexCache(),
74                                                           GetDexMethodIndex(),
75                                                           pointer_size);
76     DCHECK(ret != nullptr);
77     return ret;
78   }
79 }
80 
GetNonObsoleteMethod()81 ArtMethod* ArtMethod::GetNonObsoleteMethod() {
82   DCHECK_EQ(kRuntimePointerSize, Runtime::Current()->GetClassLinker()->GetImagePointerSize());
83   if (LIKELY(!IsObsolete())) {
84     return this;
85   } else if (IsDirect()) {
86     return &GetDeclaringClass()->GetDirectMethodsSlice(kRuntimePointerSize)[GetMethodIndex()];
87   } else {
88     return GetDeclaringClass()->GetVTableEntry(GetMethodIndex(), kRuntimePointerSize);
89   }
90 }
91 
92 template <ReadBarrierOption kReadBarrierOption>
GetSingleImplementation(PointerSize pointer_size)93 ArtMethod* ArtMethod::GetSingleImplementation(PointerSize pointer_size) {
94   if (!IsAbstract<kReadBarrierOption>()) {
95     // A non-abstract's single implementation is itself.
96     return this;
97   }
98   return reinterpret_cast<ArtMethod*>(GetDataPtrSize(pointer_size));
99 }
100 template ArtMethod* ArtMethod::GetSingleImplementation<ReadBarrierOption::kWithReadBarrier>(
101     PointerSize pointer_size);
102 template ArtMethod* ArtMethod::GetSingleImplementation<ReadBarrierOption::kWithoutReadBarrier>(
103     PointerSize pointer_size);
104 
FromReflectedMethod(const ScopedObjectAccessAlreadyRunnable & soa,jobject jlr_method)105 ArtMethod* ArtMethod::FromReflectedMethod(const ScopedObjectAccessAlreadyRunnable& soa,
106                                           jobject jlr_method) {
107   ObjPtr<mirror::Executable> executable = soa.Decode<mirror::Executable>(jlr_method);
108   DCHECK(executable != nullptr);
109   return executable->GetArtMethod();
110 }
111 
GetObsoleteDexCache()112 mirror::DexCache* ArtMethod::GetObsoleteDexCache() {
113   DCHECK(!Runtime::Current()->IsAotCompiler()) << PrettyMethod();
114   DCHECK(IsObsolete());
115   ObjPtr<mirror::ClassExt> ext(GetDeclaringClass()->GetExtData());
116   CHECK(!ext.IsNull());
117   ObjPtr<mirror::PointerArray> obsolete_methods(ext->GetObsoleteMethods());
118   CHECK(!obsolete_methods.IsNull());
119   DCHECK(ext->GetObsoleteDexCaches() != nullptr);
120   int32_t len = obsolete_methods->GetLength();
121   DCHECK_EQ(len, ext->GetObsoleteDexCaches()->GetLength());
122   // Using kRuntimePointerSize (instead of using the image's pointer size) is fine since images
123   // should never have obsolete methods in them so they should always be the same.
124   PointerSize pointer_size = kRuntimePointerSize;
125   DCHECK_EQ(kRuntimePointerSize, Runtime::Current()->GetClassLinker()->GetImagePointerSize());
126   for (int32_t i = 0; i < len; i++) {
127     if (this == obsolete_methods->GetElementPtrSize<ArtMethod*>(i, pointer_size)) {
128       return ext->GetObsoleteDexCaches()->Get(i);
129     }
130   }
131   LOG(FATAL) << "This method does not appear in the obsolete map of its class!";
132   UNREACHABLE();
133 }
134 
FindObsoleteDexClassDefIndex()135 uint16_t ArtMethod::FindObsoleteDexClassDefIndex() {
136   DCHECK(!Runtime::Current()->IsAotCompiler()) << PrettyMethod();
137   DCHECK(IsObsolete());
138   const DexFile* dex_file = GetDexFile();
139   const dex::TypeIndex declaring_class_type = dex_file->GetMethodId(GetDexMethodIndex()).class_idx_;
140   const DexFile::ClassDef* class_def = dex_file->FindClassDef(declaring_class_type);
141   CHECK(class_def != nullptr);
142   return dex_file->GetIndexForClassDef(*class_def);
143 }
144 
GetNameAsString(Thread * self)145 ObjPtr<mirror::String> ArtMethod::GetNameAsString(Thread* self) {
146   CHECK(!IsProxyMethod());
147   StackHandleScope<1> hs(self);
148   Handle<mirror::DexCache> dex_cache(hs.NewHandle(GetDexCache()));
149   auto* dex_file = dex_cache->GetDexFile();
150   uint32_t dex_method_idx = GetDexMethodIndex();
151   const DexFile::MethodId& method_id = dex_file->GetMethodId(dex_method_idx);
152   return Runtime::Current()->GetClassLinker()->ResolveString(method_id.name_idx_, dex_cache);
153 }
154 
ThrowInvocationTimeError()155 void ArtMethod::ThrowInvocationTimeError() {
156   DCHECK(!IsInvokable());
157   // NOTE: IsDefaultConflicting must be first since the actual method might or might not be abstract
158   //       due to the way we select it.
159   if (IsDefaultConflicting()) {
160     ThrowIncompatibleClassChangeErrorForMethodConflict(this);
161   } else {
162     DCHECK(IsAbstract());
163     ThrowAbstractMethodError(this);
164   }
165 }
166 
GetInvokeType()167 InvokeType ArtMethod::GetInvokeType() {
168   // TODO: kSuper?
169   if (IsStatic()) {
170     return kStatic;
171   } else if (GetDeclaringClass()->IsInterface()) {
172     return kInterface;
173   } else if (IsDirect()) {
174     return kDirect;
175   } else if (IsPolymorphicSignature()) {
176     return kPolymorphic;
177   } else {
178     return kVirtual;
179   }
180 }
181 
NumArgRegisters(const StringPiece & shorty)182 size_t ArtMethod::NumArgRegisters(const StringPiece& shorty) {
183   CHECK_LE(1U, shorty.length());
184   uint32_t num_registers = 0;
185   for (size_t i = 1; i < shorty.length(); ++i) {
186     char ch = shorty[i];
187     if (ch == 'D' || ch == 'J') {
188       num_registers += 2;
189     } else {
190       num_registers += 1;
191     }
192   }
193   return num_registers;
194 }
195 
HasSameNameAndSignature(ArtMethod * other)196 bool ArtMethod::HasSameNameAndSignature(ArtMethod* other) {
197   ScopedAssertNoThreadSuspension ants("HasSameNameAndSignature");
198   const DexFile* dex_file = GetDexFile();
199   const DexFile::MethodId& mid = dex_file->GetMethodId(GetDexMethodIndex());
200   if (GetDexCache() == other->GetDexCache()) {
201     const DexFile::MethodId& mid2 = dex_file->GetMethodId(other->GetDexMethodIndex());
202     return mid.name_idx_ == mid2.name_idx_ && mid.proto_idx_ == mid2.proto_idx_;
203   }
204   const DexFile* dex_file2 = other->GetDexFile();
205   const DexFile::MethodId& mid2 = dex_file2->GetMethodId(other->GetDexMethodIndex());
206   if (!DexFileStringEquals(dex_file, mid.name_idx_, dex_file2, mid2.name_idx_)) {
207     return false;  // Name mismatch.
208   }
209   return dex_file->GetMethodSignature(mid) == dex_file2->GetMethodSignature(mid2);
210 }
211 
FindOverriddenMethod(PointerSize pointer_size)212 ArtMethod* ArtMethod::FindOverriddenMethod(PointerSize pointer_size) {
213   if (IsStatic()) {
214     return nullptr;
215   }
216   mirror::Class* declaring_class = GetDeclaringClass();
217   mirror::Class* super_class = declaring_class->GetSuperClass();
218   uint16_t method_index = GetMethodIndex();
219   ArtMethod* result = nullptr;
220   // Did this method override a super class method? If so load the result from the super class'
221   // vtable
222   if (super_class->HasVTable() && method_index < super_class->GetVTableLength()) {
223     result = super_class->GetVTableEntry(method_index, pointer_size);
224   } else {
225     // Method didn't override superclass method so search interfaces
226     if (IsProxyMethod()) {
227       result = GetInterfaceMethodIfProxy(pointer_size);
228       DCHECK(result != nullptr);
229     } else {
230       mirror::IfTable* iftable = GetDeclaringClass()->GetIfTable();
231       for (size_t i = 0; i < iftable->Count() && result == nullptr; i++) {
232         mirror::Class* interface = iftable->GetInterface(i);
233         for (ArtMethod& interface_method : interface->GetVirtualMethods(pointer_size)) {
234           if (HasSameNameAndSignature(interface_method.GetInterfaceMethodIfProxy(pointer_size))) {
235             result = &interface_method;
236             break;
237           }
238         }
239       }
240     }
241   }
242   DCHECK(result == nullptr ||
243          GetInterfaceMethodIfProxy(pointer_size)->HasSameNameAndSignature(
244              result->GetInterfaceMethodIfProxy(pointer_size)));
245   return result;
246 }
247 
FindDexMethodIndexInOtherDexFile(const DexFile & other_dexfile,uint32_t name_and_signature_idx)248 uint32_t ArtMethod::FindDexMethodIndexInOtherDexFile(const DexFile& other_dexfile,
249                                                      uint32_t name_and_signature_idx) {
250   const DexFile* dexfile = GetDexFile();
251   const uint32_t dex_method_idx = GetDexMethodIndex();
252   const DexFile::MethodId& mid = dexfile->GetMethodId(dex_method_idx);
253   const DexFile::MethodId& name_and_sig_mid = other_dexfile.GetMethodId(name_and_signature_idx);
254   DCHECK_STREQ(dexfile->GetMethodName(mid), other_dexfile.GetMethodName(name_and_sig_mid));
255   DCHECK_EQ(dexfile->GetMethodSignature(mid), other_dexfile.GetMethodSignature(name_and_sig_mid));
256   if (dexfile == &other_dexfile) {
257     return dex_method_idx;
258   }
259   const char* mid_declaring_class_descriptor = dexfile->StringByTypeIdx(mid.class_idx_);
260   const DexFile::TypeId* other_type_id = other_dexfile.FindTypeId(mid_declaring_class_descriptor);
261   if (other_type_id != nullptr) {
262     const DexFile::MethodId* other_mid = other_dexfile.FindMethodId(
263         *other_type_id, other_dexfile.GetStringId(name_and_sig_mid.name_idx_),
264         other_dexfile.GetProtoId(name_and_sig_mid.proto_idx_));
265     if (other_mid != nullptr) {
266       return other_dexfile.GetIndexForMethodId(*other_mid);
267     }
268   }
269   return dex::kDexNoIndex;
270 }
271 
FindCatchBlock(Handle<mirror::Class> exception_type,uint32_t dex_pc,bool * has_no_move_exception)272 uint32_t ArtMethod::FindCatchBlock(Handle<mirror::Class> exception_type,
273                                    uint32_t dex_pc, bool* has_no_move_exception) {
274   // Set aside the exception while we resolve its type.
275   Thread* self = Thread::Current();
276   StackHandleScope<1> hs(self);
277   Handle<mirror::Throwable> exception(hs.NewHandle(self->GetException()));
278   self->ClearException();
279   // Default to handler not found.
280   uint32_t found_dex_pc = dex::kDexNoIndex;
281   // Iterate over the catch handlers associated with dex_pc.
282   CodeItemDataAccessor accessor(DexInstructionData());
283   for (CatchHandlerIterator it(accessor, dex_pc); it.HasNext(); it.Next()) {
284     dex::TypeIndex iter_type_idx = it.GetHandlerTypeIndex();
285     // Catch all case
286     if (!iter_type_idx.IsValid()) {
287       found_dex_pc = it.GetHandlerAddress();
288       break;
289     }
290     // Does this catch exception type apply?
291     ObjPtr<mirror::Class> iter_exception_type = ResolveClassFromTypeIndex(iter_type_idx);
292     if (UNLIKELY(iter_exception_type == nullptr)) {
293       // Now have a NoClassDefFoundError as exception. Ignore in case the exception class was
294       // removed by a pro-guard like tool.
295       // Note: this is not RI behavior. RI would have failed when loading the class.
296       self->ClearException();
297       // Delete any long jump context as this routine is called during a stack walk which will
298       // release its in use context at the end.
299       delete self->GetLongJumpContext();
300       LOG(WARNING) << "Unresolved exception class when finding catch block: "
301         << DescriptorToDot(GetTypeDescriptorFromTypeIdx(iter_type_idx));
302     } else if (iter_exception_type->IsAssignableFrom(exception_type.Get())) {
303       found_dex_pc = it.GetHandlerAddress();
304       break;
305     }
306   }
307   if (found_dex_pc != dex::kDexNoIndex) {
308     const Instruction& first_catch_instr = accessor.InstructionAt(found_dex_pc);
309     *has_no_move_exception = (first_catch_instr.Opcode() != Instruction::MOVE_EXCEPTION);
310   }
311   // Put the exception back.
312   if (exception != nullptr) {
313     self->SetException(exception.Get());
314   }
315   return found_dex_pc;
316 }
317 
Invoke(Thread * self,uint32_t * args,uint32_t args_size,JValue * result,const char * shorty)318 void ArtMethod::Invoke(Thread* self, uint32_t* args, uint32_t args_size, JValue* result,
319                        const char* shorty) {
320   if (UNLIKELY(__builtin_frame_address(0) < self->GetStackEnd())) {
321     ThrowStackOverflowError(self);
322     return;
323   }
324 
325   if (kIsDebugBuild) {
326     self->AssertThreadSuspensionIsAllowable();
327     CHECK_EQ(kRunnable, self->GetState());
328     CHECK_STREQ(GetInterfaceMethodIfProxy(kRuntimePointerSize)->GetShorty(), shorty);
329   }
330 
331   // Push a transition back into managed code onto the linked list in thread.
332   ManagedStack fragment;
333   self->PushManagedStackFragment(&fragment);
334 
335   Runtime* runtime = Runtime::Current();
336   // Call the invoke stub, passing everything as arguments.
337   // If the runtime is not yet started or it is required by the debugger, then perform the
338   // Invocation by the interpreter, explicitly forcing interpretation over JIT to prevent
339   // cycling around the various JIT/Interpreter methods that handle method invocation.
340   if (UNLIKELY(!runtime->IsStarted() || Dbg::IsForcedInterpreterNeededForCalling(self, this))) {
341     if (IsStatic()) {
342       art::interpreter::EnterInterpreterFromInvoke(
343           self, this, nullptr, args, result, /*stay_in_interpreter*/ true);
344     } else {
345       mirror::Object* receiver =
346           reinterpret_cast<StackReference<mirror::Object>*>(&args[0])->AsMirrorPtr();
347       art::interpreter::EnterInterpreterFromInvoke(
348           self, this, receiver, args + 1, result, /*stay_in_interpreter*/ true);
349     }
350   } else {
351     DCHECK_EQ(runtime->GetClassLinker()->GetImagePointerSize(), kRuntimePointerSize);
352 
353     constexpr bool kLogInvocationStartAndReturn = false;
354     bool have_quick_code = GetEntryPointFromQuickCompiledCode() != nullptr;
355     if (LIKELY(have_quick_code)) {
356       if (kLogInvocationStartAndReturn) {
357         LOG(INFO) << StringPrintf(
358             "Invoking '%s' quick code=%p static=%d", PrettyMethod().c_str(),
359             GetEntryPointFromQuickCompiledCode(), static_cast<int>(IsStatic() ? 1 : 0));
360       }
361 
362       // Ensure that we won't be accidentally calling quick compiled code when -Xint.
363       if (kIsDebugBuild && runtime->GetInstrumentation()->IsForcedInterpretOnly()) {
364         CHECK(!runtime->UseJitCompilation());
365         const void* oat_quick_code =
366             (IsNative() || !IsInvokable() || IsProxyMethod() || IsObsolete())
367             ? nullptr
368             : GetOatMethodQuickCode(runtime->GetClassLinker()->GetImagePointerSize());
369         CHECK(oat_quick_code == nullptr || oat_quick_code != GetEntryPointFromQuickCompiledCode())
370             << "Don't call compiled code when -Xint " << PrettyMethod();
371       }
372 
373       if (!IsStatic()) {
374         (*art_quick_invoke_stub)(this, args, args_size, self, result, shorty);
375       } else {
376         (*art_quick_invoke_static_stub)(this, args, args_size, self, result, shorty);
377       }
378       if (UNLIKELY(self->GetException() == Thread::GetDeoptimizationException())) {
379         // Unusual case where we were running generated code and an
380         // exception was thrown to force the activations to be removed from the
381         // stack. Continue execution in the interpreter.
382         self->DeoptimizeWithDeoptimizationException(result);
383       }
384       if (kLogInvocationStartAndReturn) {
385         LOG(INFO) << StringPrintf("Returned '%s' quick code=%p", PrettyMethod().c_str(),
386                                   GetEntryPointFromQuickCompiledCode());
387       }
388     } else {
389       LOG(INFO) << "Not invoking '" << PrettyMethod() << "' code=null";
390       if (result != nullptr) {
391         result->SetJ(0);
392       }
393     }
394   }
395 
396   // Pop transition.
397   self->PopManagedStackFragment(fragment);
398 }
399 
RegisterNative(const void * native_method)400 const void* ArtMethod::RegisterNative(const void* native_method) {
401   CHECK(IsNative()) << PrettyMethod();
402   CHECK(native_method != nullptr) << PrettyMethod();
403   void* new_native_method = nullptr;
404   Runtime::Current()->GetRuntimeCallbacks()->RegisterNativeMethod(this,
405                                                                   native_method,
406                                                                   /*out*/&new_native_method);
407   SetEntryPointFromJni(new_native_method);
408   return new_native_method;
409 }
410 
UnregisterNative()411 void ArtMethod::UnregisterNative() {
412   CHECK(IsNative()) << PrettyMethod();
413   // restore stub to lookup native pointer via dlsym
414   SetEntryPointFromJni(GetJniDlsymLookupStub());
415 }
416 
IsOverridableByDefaultMethod()417 bool ArtMethod::IsOverridableByDefaultMethod() {
418   return GetDeclaringClass()->IsInterface();
419 }
420 
IsPolymorphicSignature()421 bool ArtMethod::IsPolymorphicSignature() {
422   // Methods with a polymorphic signature have constraints that they
423   // are native and varargs and belong to either MethodHandle or VarHandle.
424   if (!IsNative() || !IsVarargs()) {
425     return false;
426   }
427   mirror::Class* cls = GetDeclaringClass();
428   return (cls == WellKnownClasses::ToClass(WellKnownClasses::java_lang_invoke_MethodHandle) ||
429           cls == WellKnownClasses::ToClass(WellKnownClasses::java_lang_invoke_VarHandle));
430 }
431 
GetOatMethodIndexFromMethodIndex(const DexFile & dex_file,uint16_t class_def_idx,uint32_t method_idx)432 static uint32_t GetOatMethodIndexFromMethodIndex(const DexFile& dex_file,
433                                                  uint16_t class_def_idx,
434                                                  uint32_t method_idx) {
435   const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_idx);
436   const uint8_t* class_data = dex_file.GetClassData(class_def);
437   CHECK(class_data != nullptr);
438   ClassDataItemIterator it(dex_file, class_data);
439   it.SkipAllFields();
440   // Process methods
441   size_t class_def_method_index = 0;
442   while (it.HasNextDirectMethod()) {
443     if (it.GetMemberIndex() == method_idx) {
444       return class_def_method_index;
445     }
446     class_def_method_index++;
447     it.Next();
448   }
449   while (it.HasNextVirtualMethod()) {
450     if (it.GetMemberIndex() == method_idx) {
451       return class_def_method_index;
452     }
453     class_def_method_index++;
454     it.Next();
455   }
456   DCHECK(!it.HasNext());
457   LOG(FATAL) << "Failed to find method index " << method_idx << " in " << dex_file.GetLocation();
458   UNREACHABLE();
459 }
460 
461 // We use the method's DexFile and declaring class name to find the OatMethod for an obsolete
462 // method.  This is extremely slow but we need it if we want to be able to have obsolete native
463 // methods since we need this to find the size of its stack frames.
464 //
465 // NB We could (potentially) do this differently and rely on the way the transformation is applied
466 // in order to use the entrypoint to find this information. However, for debugging reasons (most
467 // notably making sure that new invokes of obsolete methods fail) we choose to instead get the data
468 // directly from the dex file.
FindOatMethodFromDexFileFor(ArtMethod * method,bool * found)469 static const OatFile::OatMethod FindOatMethodFromDexFileFor(ArtMethod* method, bool* found)
470     REQUIRES_SHARED(Locks::mutator_lock_) {
471   DCHECK(method->IsObsolete() && method->IsNative());
472   const DexFile* dex_file = method->GetDexFile();
473 
474   // recreate the class_def_index from the descriptor.
475   std::string descriptor_storage;
476   const DexFile::TypeId* declaring_class_type_id =
477       dex_file->FindTypeId(method->GetDeclaringClass()->GetDescriptor(&descriptor_storage));
478   CHECK(declaring_class_type_id != nullptr);
479   dex::TypeIndex declaring_class_type_index = dex_file->GetIndexForTypeId(*declaring_class_type_id);
480   const DexFile::ClassDef* declaring_class_type_def =
481       dex_file->FindClassDef(declaring_class_type_index);
482   CHECK(declaring_class_type_def != nullptr);
483   uint16_t declaring_class_def_index = dex_file->GetIndexForClassDef(*declaring_class_type_def);
484 
485   size_t oat_method_index = GetOatMethodIndexFromMethodIndex(*dex_file,
486                                                              declaring_class_def_index,
487                                                              method->GetDexMethodIndex());
488 
489   OatFile::OatClass oat_class = OatFile::FindOatClass(*dex_file,
490                                                       declaring_class_def_index,
491                                                       found);
492   if (!(*found)) {
493     return OatFile::OatMethod::Invalid();
494   }
495   return oat_class.GetOatMethod(oat_method_index);
496 }
497 
FindOatMethodFor(ArtMethod * method,PointerSize pointer_size,bool * found)498 static const OatFile::OatMethod FindOatMethodFor(ArtMethod* method,
499                                                  PointerSize pointer_size,
500                                                  bool* found)
501     REQUIRES_SHARED(Locks::mutator_lock_) {
502   if (UNLIKELY(method->IsObsolete())) {
503     // We shouldn't be calling this with obsolete methods except for native obsolete methods for
504     // which we need to use the oat method to figure out how large the quick frame is.
505     DCHECK(method->IsNative()) << "We should only be finding the OatMethod of obsolete methods in "
506                                << "order to allow stack walking. Other obsolete methods should "
507                                << "never need to access this information.";
508     DCHECK_EQ(pointer_size, kRuntimePointerSize) << "Obsolete method in compiler!";
509     return FindOatMethodFromDexFileFor(method, found);
510   }
511   // Although we overwrite the trampoline of non-static methods, we may get here via the resolution
512   // method for direct methods (or virtual methods made direct).
513   mirror::Class* declaring_class = method->GetDeclaringClass();
514   size_t oat_method_index;
515   if (method->IsStatic() || method->IsDirect()) {
516     // Simple case where the oat method index was stashed at load time.
517     oat_method_index = method->GetMethodIndex();
518   } else {
519     // Compute the oat_method_index by search for its position in the declared virtual methods.
520     oat_method_index = declaring_class->NumDirectMethods();
521     bool found_virtual = false;
522     for (ArtMethod& art_method : declaring_class->GetVirtualMethods(pointer_size)) {
523       // Check method index instead of identity in case of duplicate method definitions.
524       if (method->GetDexMethodIndex() == art_method.GetDexMethodIndex()) {
525         found_virtual = true;
526         break;
527       }
528       oat_method_index++;
529     }
530     CHECK(found_virtual) << "Didn't find oat method index for virtual method: "
531                          << method->PrettyMethod();
532   }
533   DCHECK_EQ(oat_method_index,
534             GetOatMethodIndexFromMethodIndex(*declaring_class->GetDexCache()->GetDexFile(),
535                                              method->GetDeclaringClass()->GetDexClassDefIndex(),
536                                              method->GetDexMethodIndex()));
537   OatFile::OatClass oat_class = OatFile::FindOatClass(*declaring_class->GetDexCache()->GetDexFile(),
538                                                       declaring_class->GetDexClassDefIndex(),
539                                                       found);
540   if (!(*found)) {
541     return OatFile::OatMethod::Invalid();
542   }
543   return oat_class.GetOatMethod(oat_method_index);
544 }
545 
EqualParameters(Handle<mirror::ObjectArray<mirror::Class>> params)546 bool ArtMethod::EqualParameters(Handle<mirror::ObjectArray<mirror::Class>> params) {
547   auto* dex_cache = GetDexCache();
548   auto* dex_file = dex_cache->GetDexFile();
549   const auto& method_id = dex_file->GetMethodId(GetDexMethodIndex());
550   const auto& proto_id = dex_file->GetMethodPrototype(method_id);
551   const DexFile::TypeList* proto_params = dex_file->GetProtoParameters(proto_id);
552   auto count = proto_params != nullptr ? proto_params->Size() : 0u;
553   auto param_len = params != nullptr ? params->GetLength() : 0u;
554   if (param_len != count) {
555     return false;
556   }
557   auto* cl = Runtime::Current()->GetClassLinker();
558   for (size_t i = 0; i < count; ++i) {
559     dex::TypeIndex type_idx = proto_params->GetTypeItem(i).type_idx_;
560     ObjPtr<mirror::Class> type = cl->ResolveType(type_idx, this);
561     if (type == nullptr) {
562       Thread::Current()->AssertPendingException();
563       return false;
564     }
565     if (type != params->GetWithoutChecks(i)) {
566       return false;
567     }
568   }
569   return true;
570 }
571 
GetQuickenedInfo()572 ArrayRef<const uint8_t> ArtMethod::GetQuickenedInfo() {
573   const DexFile& dex_file = GetDeclaringClass()->GetDexFile();
574   const OatFile::OatDexFile* oat_dex_file = dex_file.GetOatDexFile();
575   if (oat_dex_file == nullptr || (oat_dex_file->GetOatFile() == nullptr)) {
576     return ArrayRef<const uint8_t>();
577   }
578   return oat_dex_file->GetOatFile()->GetVdexFile()->GetQuickenedInfoOf(dex_file,
579                                                                        GetDexMethodIndex());
580 }
581 
GetIndexFromQuickening(uint32_t dex_pc)582 uint16_t ArtMethod::GetIndexFromQuickening(uint32_t dex_pc) {
583   ArrayRef<const uint8_t> data = GetQuickenedInfo();
584   if (data.empty()) {
585     return DexFile::kDexNoIndex16;
586   }
587   QuickenInfoTable table(data);
588   uint32_t quicken_index = 0;
589   for (const DexInstructionPcPair& pair : DexInstructions()) {
590     if (pair.DexPc() == dex_pc) {
591       return table.GetData(quicken_index);
592     }
593     if (QuickenInfoTable::NeedsIndexForInstruction(&pair.Inst())) {
594       ++quicken_index;
595     }
596   }
597   return DexFile::kDexNoIndex16;
598 }
599 
GetOatQuickMethodHeader(uintptr_t pc)600 const OatQuickMethodHeader* ArtMethod::GetOatQuickMethodHeader(uintptr_t pc) {
601   // Our callers should make sure they don't pass the instrumentation exit pc,
602   // as this method does not look at the side instrumentation stack.
603   DCHECK_NE(pc, reinterpret_cast<uintptr_t>(GetQuickInstrumentationExitPc()));
604 
605   if (IsRuntimeMethod()) {
606     return nullptr;
607   }
608 
609   Runtime* runtime = Runtime::Current();
610   const void* existing_entry_point = GetEntryPointFromQuickCompiledCode();
611   CHECK(existing_entry_point != nullptr) << PrettyMethod() << "@" << this;
612   ClassLinker* class_linker = runtime->GetClassLinker();
613 
614   if (existing_entry_point == GetQuickProxyInvokeHandler()) {
615     DCHECK(IsProxyMethod() && !IsConstructor());
616     // The proxy entry point does not have any method header.
617     return nullptr;
618   }
619 
620   // Check whether the current entry point contains this pc.
621   if (!class_linker->IsQuickGenericJniStub(existing_entry_point) &&
622       !class_linker->IsQuickResolutionStub(existing_entry_point) &&
623       !class_linker->IsQuickToInterpreterBridge(existing_entry_point)) {
624     OatQuickMethodHeader* method_header =
625         OatQuickMethodHeader::FromEntryPoint(existing_entry_point);
626 
627     if (method_header->Contains(pc)) {
628       return method_header;
629     }
630   }
631 
632   // Check whether the pc is in the JIT code cache.
633   jit::Jit* jit = runtime->GetJit();
634   if (jit != nullptr) {
635     jit::JitCodeCache* code_cache = jit->GetCodeCache();
636     OatQuickMethodHeader* method_header = code_cache->LookupMethodHeader(pc, this);
637     if (method_header != nullptr) {
638       DCHECK(method_header->Contains(pc));
639       return method_header;
640     } else {
641       DCHECK(!code_cache->ContainsPc(reinterpret_cast<const void*>(pc)))
642           << PrettyMethod()
643           << ", pc=" << std::hex << pc
644           << ", entry_point=" << std::hex << reinterpret_cast<uintptr_t>(existing_entry_point)
645           << ", copy=" << std::boolalpha << IsCopied()
646           << ", proxy=" << std::boolalpha << IsProxyMethod();
647     }
648   }
649 
650   // The code has to be in an oat file.
651   bool found;
652   OatFile::OatMethod oat_method =
653       FindOatMethodFor(this, class_linker->GetImagePointerSize(), &found);
654   if (!found) {
655     if (IsNative()) {
656       // We are running the GenericJNI stub. The entrypoint may point
657       // to different entrypoints or to a JIT-compiled JNI stub.
658       DCHECK(class_linker->IsQuickGenericJniStub(existing_entry_point) ||
659              class_linker->IsQuickResolutionStub(existing_entry_point) ||
660              existing_entry_point == GetQuickInstrumentationEntryPoint() ||
661              (jit != nullptr && jit->GetCodeCache()->ContainsPc(existing_entry_point)));
662       return nullptr;
663     }
664     // Only for unit tests.
665     // TODO(ngeoffray): Update these tests to pass the right pc?
666     return OatQuickMethodHeader::FromEntryPoint(existing_entry_point);
667   }
668   const void* oat_entry_point = oat_method.GetQuickCode();
669   if (oat_entry_point == nullptr || class_linker->IsQuickGenericJniStub(oat_entry_point)) {
670     DCHECK(IsNative()) << PrettyMethod();
671     return nullptr;
672   }
673 
674   OatQuickMethodHeader* method_header = OatQuickMethodHeader::FromEntryPoint(oat_entry_point);
675   if (pc == 0) {
676     // This is a downcall, it can only happen for a native method.
677     DCHECK(IsNative());
678     return method_header;
679   }
680 
681   DCHECK(method_header->Contains(pc))
682       << PrettyMethod()
683       << " " << std::hex << pc << " " << oat_entry_point
684       << " " << (uintptr_t)(method_header->GetCode() + method_header->GetCodeSize());
685   return method_header;
686 }
687 
GetOatMethodQuickCode(PointerSize pointer_size)688 const void* ArtMethod::GetOatMethodQuickCode(PointerSize pointer_size) {
689   bool found;
690   OatFile::OatMethod oat_method = FindOatMethodFor(this, pointer_size, &found);
691   if (found) {
692     return oat_method.GetQuickCode();
693   }
694   return nullptr;
695 }
696 
HasAnyCompiledCode()697 bool ArtMethod::HasAnyCompiledCode() {
698   if (IsNative() || !IsInvokable() || IsProxyMethod()) {
699     return false;
700   }
701 
702   // Check whether the JIT has compiled it.
703   Runtime* runtime = Runtime::Current();
704   jit::Jit* jit = runtime->GetJit();
705   if (jit != nullptr && jit->GetCodeCache()->ContainsMethod(this)) {
706     return true;
707   }
708 
709   // Check whether we have AOT code.
710   return GetOatMethodQuickCode(runtime->GetClassLinker()->GetImagePointerSize()) != nullptr;
711 }
712 
SetNotIntrinsic()713 void ArtMethod::SetNotIntrinsic() {
714   if (!IsIntrinsic()) {
715     return;
716   }
717 
718   // Query the hidden API access flags of the intrinsic.
719   HiddenApiAccessFlags::ApiList intrinsic_api_list = GetHiddenApiAccessFlags();
720 
721   // Clear intrinsic-related access flags.
722   ClearAccessFlags(kAccIntrinsic | kAccIntrinsicBits);
723 
724   // Re-apply hidden API access flags now that the method is not an intrinsic.
725   SetAccessFlags(HiddenApiAccessFlags::EncodeForRuntime(GetAccessFlags(), intrinsic_api_list));
726   DCHECK_EQ(GetHiddenApiAccessFlags(), intrinsic_api_list);
727 }
728 
729 
CopyFrom(ArtMethod * src,PointerSize image_pointer_size)730 void ArtMethod::CopyFrom(ArtMethod* src, PointerSize image_pointer_size) {
731   memcpy(reinterpret_cast<void*>(this), reinterpret_cast<const void*>(src),
732          Size(image_pointer_size));
733   declaring_class_ = GcRoot<mirror::Class>(const_cast<ArtMethod*>(src)->GetDeclaringClass());
734 
735   // If the entry point of the method we are copying from is from JIT code, we just
736   // put the entry point of the new method to interpreter or GenericJNI. We could set
737   // the entry point to the JIT code, but this would require taking the JIT code cache
738   // lock to notify it, which we do not want at this level.
739   Runtime* runtime = Runtime::Current();
740   if (runtime->UseJitCompilation()) {
741     if (runtime->GetJit()->GetCodeCache()->ContainsPc(GetEntryPointFromQuickCompiledCode())) {
742       SetEntryPointFromQuickCompiledCodePtrSize(
743           src->IsNative() ? GetQuickGenericJniStub() : GetQuickToInterpreterBridge(),
744           image_pointer_size);
745     }
746   }
747   // Clear the profiling info for the same reasons as the JIT code.
748   if (!src->IsNative()) {
749     SetProfilingInfoPtrSize(nullptr, image_pointer_size);
750   }
751   // Clear hotness to let the JIT properly decide when to compile this method.
752   hotness_count_ = 0;
753 }
754 
IsImagePointerSize(PointerSize pointer_size)755 bool ArtMethod::IsImagePointerSize(PointerSize pointer_size) {
756   // Hijack this function to get access to PtrSizedFieldsOffset.
757   //
758   // Ensure that PrtSizedFieldsOffset is correct. We rely here on usually having both 32-bit and
759   // 64-bit builds.
760   static_assert(std::is_standard_layout<ArtMethod>::value, "ArtMethod is not standard layout.");
761   static_assert(
762       (sizeof(void*) != 4) ||
763           (offsetof(ArtMethod, ptr_sized_fields_) == PtrSizedFieldsOffset(PointerSize::k32)),
764       "Unexpected 32-bit class layout.");
765   static_assert(
766       (sizeof(void*) != 8) ||
767           (offsetof(ArtMethod, ptr_sized_fields_) == PtrSizedFieldsOffset(PointerSize::k64)),
768       "Unexpected 64-bit class layout.");
769 
770   Runtime* runtime = Runtime::Current();
771   if (runtime == nullptr) {
772     return true;
773   }
774   return runtime->GetClassLinker()->GetImagePointerSize() == pointer_size;
775 }
776 
PrettyMethod(ArtMethod * m,bool with_signature)777 std::string ArtMethod::PrettyMethod(ArtMethod* m, bool with_signature) {
778   if (m == nullptr) {
779     return "null";
780   }
781   return m->PrettyMethod(with_signature);
782 }
783 
PrettyMethod(bool with_signature)784 std::string ArtMethod::PrettyMethod(bool with_signature) {
785   if (UNLIKELY(IsRuntimeMethod())) {
786     std::string result = GetDeclaringClassDescriptor();
787     result += '.';
788     result += GetName();
789     // Do not add "<no signature>" even if `with_signature` is true.
790     return result;
791   }
792   ArtMethod* m =
793       GetInterfaceMethodIfProxy(Runtime::Current()->GetClassLinker()->GetImagePointerSize());
794   return m->GetDexFile()->PrettyMethod(m->GetDexMethodIndex(), with_signature);
795 }
796 
JniShortName()797 std::string ArtMethod::JniShortName() {
798   return GetJniShortName(GetDeclaringClassDescriptor(), GetName());
799 }
800 
JniLongName()801 std::string ArtMethod::JniLongName() {
802   std::string long_name;
803   long_name += JniShortName();
804   long_name += "__";
805 
806   std::string signature(GetSignature().ToString());
807   signature.erase(0, 1);
808   signature.erase(signature.begin() + signature.find(')'), signature.end());
809 
810   long_name += MangleForJni(signature);
811 
812   return long_name;
813 }
814 
815 // AssertSharedHeld doesn't work in GetAccessFlags, so use a NO_THREAD_SAFETY_ANALYSIS helper.
816 // TODO: Figure out why ASSERT_SHARED_CAPABILITY doesn't work.
817 template <ReadBarrierOption kReadBarrierOption>
DoGetAccessFlagsHelper(ArtMethod * method)818 ALWAYS_INLINE static inline void DoGetAccessFlagsHelper(ArtMethod* method)
819     NO_THREAD_SAFETY_ANALYSIS {
820   CHECK(method->IsRuntimeMethod() ||
821         method->GetDeclaringClass<kReadBarrierOption>()->IsIdxLoaded() ||
822         method->GetDeclaringClass<kReadBarrierOption>()->IsErroneous());
823 }
824 
GetAccessFlagsDCheck()825 template <ReadBarrierOption kReadBarrierOption> void ArtMethod::GetAccessFlagsDCheck() {
826   if (kCheckDeclaringClassState) {
827     Thread* self = Thread::Current();
828     if (!Locks::mutator_lock_->IsSharedHeld(self)) {
829       if (self->IsThreadSuspensionAllowable()) {
830         ScopedObjectAccess soa(self);
831         CHECK(IsRuntimeMethod() ||
832               GetDeclaringClass<kReadBarrierOption>()->IsIdxLoaded() ||
833               GetDeclaringClass<kReadBarrierOption>()->IsErroneous());
834       }
835     } else {
836       // We cannot use SOA in this case. We might be holding the lock, but may not be in the
837       // runnable state (e.g., during GC).
838       Locks::mutator_lock_->AssertSharedHeld(self);
839       DoGetAccessFlagsHelper<kReadBarrierOption>(this);
840     }
841   }
842 }
843 template void ArtMethod::GetAccessFlagsDCheck<ReadBarrierOption::kWithReadBarrier>();
844 template void ArtMethod::GetAccessFlagsDCheck<ReadBarrierOption::kWithoutReadBarrier>();
845 
846 }  // namespace art
847