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 "arch/context.h"
20#include "art_field-inl.h"
21#include "art_method-inl.h"
22#include "base/stringpiece.h"
23#include "class_linker-inl.h"
24#include "debugger.h"
25#include "dex_file-inl.h"
26#include "dex_instruction.h"
27#include "entrypoints/runtime_asm_entrypoints.h"
28#include "gc/accounting/card_table-inl.h"
29#include "interpreter/interpreter.h"
30#include "jit/jit.h"
31#include "jit/jit_code_cache.h"
32#include "jit/profiling_info.h"
33#include "jni_internal.h"
34#include "mirror/abstract_method.h"
35#include "mirror/class-inl.h"
36#include "mirror/object_array-inl.h"
37#include "mirror/object-inl.h"
38#include "mirror/string.h"
39#include "oat_file-inl.h"
40#include "scoped_thread_state_change.h"
41#include "well_known_classes.h"
42
43namespace art {
44
45extern "C" void art_quick_invoke_stub(ArtMethod*, uint32_t*, uint32_t, Thread*, JValue*,
46                                      const char*);
47extern "C" void art_quick_invoke_static_stub(ArtMethod*, uint32_t*, uint32_t, Thread*, JValue*,
48                                             const char*);
49
50ArtMethod* ArtMethod::FromReflectedMethod(const ScopedObjectAccessAlreadyRunnable& soa,
51                                          jobject jlr_method) {
52  auto* abstract_method = soa.Decode<mirror::AbstractMethod*>(jlr_method);
53  DCHECK(abstract_method != nullptr);
54  return abstract_method->GetArtMethod();
55}
56
57mirror::String* ArtMethod::GetNameAsString(Thread* self) {
58  CHECK(!IsProxyMethod());
59  StackHandleScope<1> hs(self);
60  Handle<mirror::DexCache> dex_cache(hs.NewHandle(GetDexCache()));
61  auto* dex_file = dex_cache->GetDexFile();
62  uint32_t dex_method_idx = GetDexMethodIndex();
63  const DexFile::MethodId& method_id = dex_file->GetMethodId(dex_method_idx);
64  return Runtime::Current()->GetClassLinker()->ResolveString(*dex_file, method_id.name_idx_,
65                                                             dex_cache);
66}
67
68void ArtMethod::ThrowInvocationTimeError() {
69  DCHECK(!IsInvokable());
70  // NOTE: IsDefaultConflicting must be first since the actual method might or might not be abstract
71  //       due to the way we select it.
72  if (IsDefaultConflicting()) {
73    ThrowIncompatibleClassChangeErrorForMethodConflict(this);
74  } else {
75    DCHECK(IsAbstract());
76    ThrowAbstractMethodError(this);
77  }
78}
79
80InvokeType ArtMethod::GetInvokeType() {
81  // TODO: kSuper?
82  if (IsStatic()) {
83    return kStatic;
84  } else if (GetDeclaringClass()->IsInterface()) {
85    return kInterface;
86  } else if (IsDirect()) {
87    return kDirect;
88  } else {
89    return kVirtual;
90  }
91}
92
93size_t ArtMethod::NumArgRegisters(const StringPiece& shorty) {
94  CHECK_LE(1U, shorty.length());
95  uint32_t num_registers = 0;
96  for (size_t i = 1; i < shorty.length(); ++i) {
97    char ch = shorty[i];
98    if (ch == 'D' || ch == 'J') {
99      num_registers += 2;
100    } else {
101      num_registers += 1;
102    }
103  }
104  return num_registers;
105}
106
107bool ArtMethod::HasSameNameAndSignature(ArtMethod* other) {
108  ScopedAssertNoThreadSuspension ants(Thread::Current(), "HasSameNameAndSignature");
109  const DexFile* dex_file = GetDexFile();
110  const DexFile::MethodId& mid = dex_file->GetMethodId(GetDexMethodIndex());
111  if (GetDexCache() == other->GetDexCache()) {
112    const DexFile::MethodId& mid2 = dex_file->GetMethodId(other->GetDexMethodIndex());
113    return mid.name_idx_ == mid2.name_idx_ && mid.proto_idx_ == mid2.proto_idx_;
114  }
115  const DexFile* dex_file2 = other->GetDexFile();
116  const DexFile::MethodId& mid2 = dex_file2->GetMethodId(other->GetDexMethodIndex());
117  if (!DexFileStringEquals(dex_file, mid.name_idx_, dex_file2, mid2.name_idx_)) {
118    return false;  // Name mismatch.
119  }
120  return dex_file->GetMethodSignature(mid) == dex_file2->GetMethodSignature(mid2);
121}
122
123ArtMethod* ArtMethod::FindOverriddenMethod(size_t pointer_size) {
124  if (IsStatic()) {
125    return nullptr;
126  }
127  mirror::Class* declaring_class = GetDeclaringClass();
128  mirror::Class* super_class = declaring_class->GetSuperClass();
129  uint16_t method_index = GetMethodIndex();
130  ArtMethod* result = nullptr;
131  // Did this method override a super class method? If so load the result from the super class'
132  // vtable
133  if (super_class->HasVTable() && method_index < super_class->GetVTableLength()) {
134    result = super_class->GetVTableEntry(method_index, pointer_size);
135  } else {
136    // Method didn't override superclass method so search interfaces
137    if (IsProxyMethod()) {
138      result = mirror::DexCache::GetElementPtrSize(GetDexCacheResolvedMethods(pointer_size),
139                                                   GetDexMethodIndex(),
140                                                   pointer_size);
141      CHECK_EQ(result,
142               Runtime::Current()->GetClassLinker()->FindMethodForProxy(GetDeclaringClass(), this));
143    } else {
144      mirror::IfTable* iftable = GetDeclaringClass()->GetIfTable();
145      for (size_t i = 0; i < iftable->Count() && result == nullptr; i++) {
146        mirror::Class* interface = iftable->GetInterface(i);
147        for (ArtMethod& interface_method : interface->GetVirtualMethods(pointer_size)) {
148          if (HasSameNameAndSignature(interface_method.GetInterfaceMethodIfProxy(pointer_size))) {
149            result = &interface_method;
150            break;
151          }
152        }
153      }
154    }
155  }
156  DCHECK(result == nullptr ||
157         GetInterfaceMethodIfProxy(pointer_size)->HasSameNameAndSignature(
158             result->GetInterfaceMethodIfProxy(pointer_size)));
159  return result;
160}
161
162uint32_t ArtMethod::FindDexMethodIndexInOtherDexFile(const DexFile& other_dexfile,
163                                                     uint32_t name_and_signature_idx) {
164  const DexFile* dexfile = GetDexFile();
165  const uint32_t dex_method_idx = GetDexMethodIndex();
166  const DexFile::MethodId& mid = dexfile->GetMethodId(dex_method_idx);
167  const DexFile::MethodId& name_and_sig_mid = other_dexfile.GetMethodId(name_and_signature_idx);
168  DCHECK_STREQ(dexfile->GetMethodName(mid), other_dexfile.GetMethodName(name_and_sig_mid));
169  DCHECK_EQ(dexfile->GetMethodSignature(mid), other_dexfile.GetMethodSignature(name_and_sig_mid));
170  if (dexfile == &other_dexfile) {
171    return dex_method_idx;
172  }
173  const char* mid_declaring_class_descriptor = dexfile->StringByTypeIdx(mid.class_idx_);
174  const DexFile::TypeId* other_type_id = other_dexfile.FindTypeId(mid_declaring_class_descriptor);
175  if (other_type_id != nullptr) {
176    const DexFile::MethodId* other_mid = other_dexfile.FindMethodId(
177        *other_type_id, other_dexfile.GetStringId(name_and_sig_mid.name_idx_),
178        other_dexfile.GetProtoId(name_and_sig_mid.proto_idx_));
179    if (other_mid != nullptr) {
180      return other_dexfile.GetIndexForMethodId(*other_mid);
181    }
182  }
183  return DexFile::kDexNoIndex;
184}
185
186uint32_t ArtMethod::FindCatchBlock(Handle<mirror::Class> exception_type,
187                                   uint32_t dex_pc, bool* has_no_move_exception) {
188  const DexFile::CodeItem* code_item = GetCodeItem();
189  // Set aside the exception while we resolve its type.
190  Thread* self = Thread::Current();
191  StackHandleScope<1> hs(self);
192  Handle<mirror::Throwable> exception(hs.NewHandle(self->GetException()));
193  self->ClearException();
194  // Default to handler not found.
195  uint32_t found_dex_pc = DexFile::kDexNoIndex;
196  // Iterate over the catch handlers associated with dex_pc.
197  size_t pointer_size = Runtime::Current()->GetClassLinker()->GetImagePointerSize();
198  for (CatchHandlerIterator it(*code_item, dex_pc); it.HasNext(); it.Next()) {
199    uint16_t iter_type_idx = it.GetHandlerTypeIndex();
200    // Catch all case
201    if (iter_type_idx == DexFile::kDexNoIndex16) {
202      found_dex_pc = it.GetHandlerAddress();
203      break;
204    }
205    // Does this catch exception type apply?
206    mirror::Class* iter_exception_type = GetClassFromTypeIndex(iter_type_idx,
207                                                               true /* resolve */,
208                                                               pointer_size);
209    if (UNLIKELY(iter_exception_type == nullptr)) {
210      // Now have a NoClassDefFoundError as exception. Ignore in case the exception class was
211      // removed by a pro-guard like tool.
212      // Note: this is not RI behavior. RI would have failed when loading the class.
213      self->ClearException();
214      // Delete any long jump context as this routine is called during a stack walk which will
215      // release its in use context at the end.
216      delete self->GetLongJumpContext();
217      LOG(WARNING) << "Unresolved exception class when finding catch block: "
218        << DescriptorToDot(GetTypeDescriptorFromTypeIdx(iter_type_idx));
219    } else if (iter_exception_type->IsAssignableFrom(exception_type.Get())) {
220      found_dex_pc = it.GetHandlerAddress();
221      break;
222    }
223  }
224  if (found_dex_pc != DexFile::kDexNoIndex) {
225    const Instruction* first_catch_instr =
226        Instruction::At(&code_item->insns_[found_dex_pc]);
227    *has_no_move_exception = (first_catch_instr->Opcode() != Instruction::MOVE_EXCEPTION);
228  }
229  // Put the exception back.
230  if (exception.Get() != nullptr) {
231    self->SetException(exception.Get());
232  }
233  return found_dex_pc;
234}
235
236void ArtMethod::Invoke(Thread* self, uint32_t* args, uint32_t args_size, JValue* result,
237                       const char* shorty) {
238  if (UNLIKELY(__builtin_frame_address(0) < self->GetStackEnd())) {
239    ThrowStackOverflowError(self);
240    return;
241  }
242
243  if (kIsDebugBuild) {
244    self->AssertThreadSuspensionIsAllowable();
245    CHECK_EQ(kRunnable, self->GetState());
246    CHECK_STREQ(GetInterfaceMethodIfProxy(sizeof(void*))->GetShorty(), shorty);
247  }
248
249  // Push a transition back into managed code onto the linked list in thread.
250  ManagedStack fragment;
251  self->PushManagedStackFragment(&fragment);
252
253  Runtime* runtime = Runtime::Current();
254  // Call the invoke stub, passing everything as arguments.
255  // If the runtime is not yet started or it is required by the debugger, then perform the
256  // Invocation by the interpreter, explicitly forcing interpretation over JIT to prevent
257  // cycling around the various JIT/Interpreter methods that handle method invocation.
258  if (UNLIKELY(!runtime->IsStarted() || Dbg::IsForcedInterpreterNeededForCalling(self, this))) {
259    if (IsStatic()) {
260      art::interpreter::EnterInterpreterFromInvoke(
261          self, this, nullptr, args, result, /*stay_in_interpreter*/ true);
262    } else {
263      mirror::Object* receiver =
264          reinterpret_cast<StackReference<mirror::Object>*>(&args[0])->AsMirrorPtr();
265      art::interpreter::EnterInterpreterFromInvoke(
266          self, this, receiver, args + 1, result, /*stay_in_interpreter*/ true);
267    }
268  } else {
269    DCHECK_EQ(runtime->GetClassLinker()->GetImagePointerSize(), sizeof(void*));
270
271    constexpr bool kLogInvocationStartAndReturn = false;
272    bool have_quick_code = GetEntryPointFromQuickCompiledCode() != nullptr;
273    if (LIKELY(have_quick_code)) {
274      if (kLogInvocationStartAndReturn) {
275        LOG(INFO) << StringPrintf(
276            "Invoking '%s' quick code=%p static=%d", PrettyMethod(this).c_str(),
277            GetEntryPointFromQuickCompiledCode(), static_cast<int>(IsStatic() ? 1 : 0));
278      }
279
280      // Ensure that we won't be accidentally calling quick compiled code when -Xint.
281      if (kIsDebugBuild && runtime->GetInstrumentation()->IsForcedInterpretOnly()) {
282        CHECK(!runtime->UseJitCompilation());
283        const void* oat_quick_code = runtime->GetClassLinker()->GetOatMethodQuickCodeFor(this);
284        CHECK(oat_quick_code == nullptr || oat_quick_code != GetEntryPointFromQuickCompiledCode())
285            << "Don't call compiled code when -Xint " << PrettyMethod(this);
286      }
287
288      if (!IsStatic()) {
289        (*art_quick_invoke_stub)(this, args, args_size, self, result, shorty);
290      } else {
291        (*art_quick_invoke_static_stub)(this, args, args_size, self, result, shorty);
292      }
293      if (UNLIKELY(self->GetException() == Thread::GetDeoptimizationException())) {
294        // Unusual case where we were running generated code and an
295        // exception was thrown to force the activations to be removed from the
296        // stack. Continue execution in the interpreter.
297        self->DeoptimizeWithDeoptimizationException(result);
298      }
299      if (kLogInvocationStartAndReturn) {
300        LOG(INFO) << StringPrintf("Returned '%s' quick code=%p", PrettyMethod(this).c_str(),
301                                  GetEntryPointFromQuickCompiledCode());
302      }
303    } else {
304      LOG(INFO) << "Not invoking '" << PrettyMethod(this) << "' code=null";
305      if (result != nullptr) {
306        result->SetJ(0);
307      }
308    }
309  }
310
311  // Pop transition.
312  self->PopManagedStackFragment(fragment);
313}
314
315void ArtMethod::RegisterNative(const void* native_method, bool is_fast) {
316  CHECK(IsNative()) << PrettyMethod(this);
317  CHECK(!IsFastNative()) << PrettyMethod(this);
318  CHECK(native_method != nullptr) << PrettyMethod(this);
319  if (is_fast) {
320    SetAccessFlags(GetAccessFlags() | kAccFastNative);
321  }
322  SetEntryPointFromJni(native_method);
323}
324
325void ArtMethod::UnregisterNative() {
326  CHECK(IsNative() && !IsFastNative()) << PrettyMethod(this);
327  // restore stub to lookup native pointer via dlsym
328  RegisterNative(GetJniDlsymLookupStub(), false);
329}
330
331bool ArtMethod::IsOverridableByDefaultMethod() {
332  return GetDeclaringClass()->IsInterface();
333}
334
335bool ArtMethod::EqualParameters(Handle<mirror::ObjectArray<mirror::Class>> params) {
336  auto* dex_cache = GetDexCache();
337  auto* dex_file = dex_cache->GetDexFile();
338  const auto& method_id = dex_file->GetMethodId(GetDexMethodIndex());
339  const auto& proto_id = dex_file->GetMethodPrototype(method_id);
340  const DexFile::TypeList* proto_params = dex_file->GetProtoParameters(proto_id);
341  auto count = proto_params != nullptr ? proto_params->Size() : 0u;
342  auto param_len = params.Get() != nullptr ? params->GetLength() : 0u;
343  if (param_len != count) {
344    return false;
345  }
346  auto* cl = Runtime::Current()->GetClassLinker();
347  for (size_t i = 0; i < count; ++i) {
348    auto type_idx = proto_params->GetTypeItem(i).type_idx_;
349    auto* type = cl->ResolveType(type_idx, this);
350    if (type == nullptr) {
351      Thread::Current()->AssertPendingException();
352      return false;
353    }
354    if (type != params->GetWithoutChecks(i)) {
355      return false;
356    }
357  }
358  return true;
359}
360
361const uint8_t* ArtMethod::GetQuickenedInfo() {
362  bool found = false;
363  OatFile::OatMethod oat_method =
364      Runtime::Current()->GetClassLinker()->FindOatMethodFor(this, &found);
365  if (!found || (oat_method.GetQuickCode() != nullptr)) {
366    return nullptr;
367  }
368  return oat_method.GetVmapTable();
369}
370
371const OatQuickMethodHeader* ArtMethod::GetOatQuickMethodHeader(uintptr_t pc) {
372  // Our callers should make sure they don't pass the instrumentation exit pc,
373  // as this method does not look at the side instrumentation stack.
374  DCHECK_NE(pc, reinterpret_cast<uintptr_t>(GetQuickInstrumentationExitPc()));
375
376  if (IsRuntimeMethod()) {
377    return nullptr;
378  }
379
380  Runtime* runtime = Runtime::Current();
381  const void* existing_entry_point = GetEntryPointFromQuickCompiledCode();
382  CHECK(existing_entry_point != nullptr) << PrettyMethod(this) << "@" << this;
383  ClassLinker* class_linker = runtime->GetClassLinker();
384
385  if (class_linker->IsQuickGenericJniStub(existing_entry_point)) {
386    // The generic JNI does not have any method header.
387    return nullptr;
388  }
389
390  if (existing_entry_point == GetQuickProxyInvokeHandler()) {
391    DCHECK(IsProxyMethod() && !IsConstructor());
392    // The proxy entry point does not have any method header.
393    return nullptr;
394  }
395
396  // Check whether the current entry point contains this pc.
397  if (!class_linker->IsQuickResolutionStub(existing_entry_point) &&
398      !class_linker->IsQuickToInterpreterBridge(existing_entry_point)) {
399    OatQuickMethodHeader* method_header =
400        OatQuickMethodHeader::FromEntryPoint(existing_entry_point);
401
402    if (method_header->Contains(pc)) {
403      return method_header;
404    }
405  }
406
407  // Check whether the pc is in the JIT code cache.
408  jit::Jit* jit = Runtime::Current()->GetJit();
409  if (jit != nullptr) {
410    jit::JitCodeCache* code_cache = jit->GetCodeCache();
411    OatQuickMethodHeader* method_header = code_cache->LookupMethodHeader(pc, this);
412    if (method_header != nullptr) {
413      DCHECK(method_header->Contains(pc));
414      return method_header;
415    } else {
416      DCHECK(!code_cache->ContainsPc(reinterpret_cast<const void*>(pc)))
417          << PrettyMethod(this)
418          << ", pc=" << std::hex << pc
419          << ", entry_point=" << std::hex << reinterpret_cast<uintptr_t>(existing_entry_point)
420          << ", copy=" << std::boolalpha << IsCopied()
421          << ", proxy=" << std::boolalpha << IsProxyMethod();
422    }
423  }
424
425  // The code has to be in an oat file.
426  bool found;
427  OatFile::OatMethod oat_method = class_linker->FindOatMethodFor(this, &found);
428  if (!found) {
429    if (class_linker->IsQuickResolutionStub(existing_entry_point)) {
430      // We are running the generic jni stub, but the entry point of the method has not
431      // been updated yet.
432      DCHECK_EQ(pc, 0u) << "Should be a downcall";
433      DCHECK(IsNative());
434      return nullptr;
435    }
436    if (existing_entry_point == GetQuickInstrumentationEntryPoint()) {
437      // We are running the generic jni stub, but the method is being instrumented.
438      DCHECK_EQ(pc, 0u) << "Should be a downcall";
439      DCHECK(IsNative());
440      return nullptr;
441    }
442    // Only for unit tests.
443    // TODO(ngeoffray): Update these tests to pass the right pc?
444    return OatQuickMethodHeader::FromEntryPoint(existing_entry_point);
445  }
446  const void* oat_entry_point = oat_method.GetQuickCode();
447  if (oat_entry_point == nullptr || class_linker->IsQuickGenericJniStub(oat_entry_point)) {
448    DCHECK(IsNative()) << PrettyMethod(this);
449    return nullptr;
450  }
451
452  OatQuickMethodHeader* method_header = OatQuickMethodHeader::FromEntryPoint(oat_entry_point);
453  if (pc == 0) {
454    // This is a downcall, it can only happen for a native method.
455    DCHECK(IsNative());
456    return method_header;
457  }
458
459  DCHECK(method_header->Contains(pc))
460      << PrettyMethod(this)
461      << std::hex << pc << " " << oat_entry_point
462      << " " << (uintptr_t)(method_header->code_ + method_header->code_size_);
463  return method_header;
464}
465
466bool ArtMethod::HasAnyCompiledCode() {
467  // Check whether the JIT has compiled it.
468  jit::Jit* jit = Runtime::Current()->GetJit();
469  if (jit != nullptr && jit->GetCodeCache()->ContainsMethod(this)) {
470    return true;
471  }
472
473  // Check whether we have AOT code.
474  return Runtime::Current()->GetClassLinker()->GetOatMethodQuickCodeFor(this) != nullptr;
475}
476
477void ArtMethod::CopyFrom(ArtMethod* src, size_t image_pointer_size) {
478  memcpy(reinterpret_cast<void*>(this), reinterpret_cast<const void*>(src),
479         Size(image_pointer_size));
480  declaring_class_ = GcRoot<mirror::Class>(const_cast<ArtMethod*>(src)->GetDeclaringClass());
481
482  // If the entry point of the method we are copying from is from JIT code, we just
483  // put the entry point of the new method to interpreter. We could set the entry point
484  // to the JIT code, but this would require taking the JIT code cache lock to notify
485  // it, which we do not want at this level.
486  Runtime* runtime = Runtime::Current();
487  if (runtime->UseJitCompilation()) {
488    if (runtime->GetJit()->GetCodeCache()->ContainsPc(GetEntryPointFromQuickCompiledCode())) {
489      SetEntryPointFromQuickCompiledCodePtrSize(GetQuickToInterpreterBridge(), image_pointer_size);
490    }
491  }
492  // Clear the profiling info for the same reasons as the JIT code.
493  if (!src->IsNative()) {
494    SetProfilingInfoPtrSize(nullptr, image_pointer_size);
495  }
496  // Clear hotness to let the JIT properly decide when to compile this method.
497  hotness_count_ = 0;
498}
499
500}  // namespace art
501