stub-cache.cc.svn-base

Google浏览器V8内核代码

  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    KeyedLoadStubCompiler compiler;
    code = compiler.CompileLoadFunctionPrototype(name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("KeyedLoadIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return code;
}


Object* StubCache::ComputeStoreField(String* name,
                                     JSObject* receiver,
                                     int field_index,
                                     Map* transition) {
  PropertyType type = (transition == NULL) ? FIELD : MAP_TRANSITION;
  Code::Flags flags = Code::ComputeMonomorphicFlags(Code::STORE_IC, type);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    StoreStubCompiler compiler;
    code = compiler.CompileStoreField(receiver, field_index, transition, name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("StoreIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return Set(name, receiver->map(), Code::cast(code));
}


Object* StubCache::ComputeStoreCallback(String* name,
                                        JSObject* receiver,
                                        AccessorInfo* callback) {
  ASSERT(v8::ToCData<Address>(callback->setter()) != 0);
  Code::Flags flags = Code::ComputeMonomorphicFlags(Code::STORE_IC, CALLBACKS);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    StoreStubCompiler compiler;
    code = compiler.CompileStoreCallback(receiver, callback, name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("StoreIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return Set(name, receiver->map(), Code::cast(code));
}


Object* StubCache::ComputeStoreInterceptor(String* name,
                                           JSObject* receiver) {
  Code::Flags flags =
      Code::ComputeMonomorphicFlags(Code::STORE_IC, INTERCEPTOR);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    StoreStubCompiler compiler;
    code = compiler.CompileStoreInterceptor(receiver, name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("StoreIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return Set(name, receiver->map(), Code::cast(code));
}


Object* StubCache::ComputeKeyedStoreField(String* name, JSObject* receiver,
                                          int field_index, Map* transition) {
  PropertyType type = (transition == NULL) ? FIELD : MAP_TRANSITION;
  Code::Flags flags = Code::ComputeMonomorphicFlags(Code::KEYED_STORE_IC, type);
  Object* code = receiver->map()->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    KeyedStoreStubCompiler compiler;
    code = compiler.CompileStoreField(receiver, field_index, transition, name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("KeyedStoreIC", Code::cast(code), name));
    Object* result = receiver->map()->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return code;
}


Object* StubCache::ComputeCallConstant(int argc,
                                       String* name,
                                       Object* object,
                                       JSObject* holder,
                                       JSFunction* function) {
  // Compute the check type and the map.
  Map* map = IC::GetCodeCacheMapForObject(object);

  // Compute check type based on receiver/holder.
  StubCompiler::CheckType check = StubCompiler::RECEIVER_MAP_CHECK;
  if (object->IsString()) {
    check = StubCompiler::STRING_CHECK;
  } else if (object->IsNumber()) {
    check = StubCompiler::NUMBER_CHECK;
  } else if (object->IsBoolean()) {
    check = StubCompiler::BOOLEAN_CHECK;
  }

  Code::Flags flags =
      Code::ComputeMonomorphicFlags(Code::CALL_IC, CONSTANT_FUNCTION, argc);
  Object* code = map->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    if (object->IsJSObject()) {
      Object* opt =
          Top::LookupSpecialFunction(JSObject::cast(object), holder, function);
      if (opt->IsJSFunction()) {
        check = StubCompiler::JSARRAY_HAS_FAST_ELEMENTS_CHECK;
        function = JSFunction::cast(opt);
      }
    }
    // If the function hasn't been compiled yet, we cannot do it now
    // because it may cause GC. To avoid this issue, we return an
    // internal error which will make sure we do not update any
    // caches.
    if (!function->is_compiled()) return Failure::InternalError();
    // Compile the stub - only create stubs for fully compiled functions.
    CallStubCompiler compiler(argc);
    code = compiler.CompileCallConstant(object, holder, function, check);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("CallIC", Code::cast(code), name));
    Object* result = map->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return Set(name, map, Code::cast(code));
}


Object* StubCache::ComputeCallField(int argc,
                                    String* name,
                                    Object* object,
                                    JSObject* holder,
                                    int index) {
  // Compute the check type and the map.
  Map* map = IC::GetCodeCacheMapForObject(object);

  // TODO(1233596): We cannot do receiver map check for non-JS objects
  // because they may be represented as immediates without a
  // map. Instead, we check against the map in the holder.
  if (object->IsNumber() || object->IsBoolean() || object->IsString()) {
    object = holder;
  }

  Code::Flags flags = Code::ComputeMonomorphicFlags(Code::CALL_IC, FIELD, argc);
  Object* code = map->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    CallStubCompiler compiler(argc);
    code = compiler.CompileCallField(object, holder, index);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("CallIC", Code::cast(code), name));
    Object* result = map->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return Set(name, map, Code::cast(code));
}


Object* StubCache::ComputeCallInterceptor(int argc,
                                          String* name,
                                          Object* object,
                                          JSObject* holder) {
  // Compute the check type and the map.
  // If the object is a value, we use the prototype map for the cache.
  Map* map = IC::GetCodeCacheMapForObject(object);

  // TODO(1233596): We cannot do receiver map check for non-JS objects
  // because they may be represented as immediates without a
  // map. Instead, we check against the map in the holder.
  if (object->IsNumber() || object->IsBoolean() || object->IsString()) {
    object = holder;
  }

  Code::Flags flags =
      Code::ComputeMonomorphicFlags(Code::CALL_IC, INTERCEPTOR, argc);
  Object* code = map->FindInCodeCache(name, flags);
  if (code->IsUndefined()) {
    CallStubCompiler compiler(argc);
    code = compiler.CompileCallInterceptor(object, holder, name);
    if (code->IsFailure()) return code;
    LOG(CodeCreateEvent("CallIC", Code::cast(code), name));
    Object* result = map->UpdateCodeCache(name, Code::cast(code));
    if (result->IsFailure()) return result;
  }
  return Set(name, map, Code::cast(code));
}


Object* StubCache::ComputeCallNormal(int argc,
                                     String* name,
                                     JSObject* receiver) {
  Object* code = ComputeCallNormal(argc);
  if (code->IsFailure()) return code;
  return Set(name, receiver->map(), Code::cast(code));
}


static Object* GetProbeValue(Code::Flags flags) {
  Dictionary* dictionary = Heap::non_monomorphic_cache();
  int entry = dictionary->FindNumberEntry(flags);
  if (entry != -1) return dictionary->ValueAt(entry);
  return Heap::undefined_value();
}


static Object* ProbeCache(Code::Flags flags) {
  Object* probe = GetProbeValue(flags);
  if (probe != Heap::undefined_value()) return probe;
  // Seed the cache with an undefined value to make sure that any
  // generated code object can always be inserted into the cache
  // without causing  allocation failures.
  Object* result =
      Heap::non_monomorphic_cache()->AtNumberPut(flags,
                                                 Heap::undefined_value());
  if (result->IsFailure()) return result;
  Heap::set_non_monomorphic_cache(Dictionary::cast(result));
  return probe;
}


static Object* FillCache(Object* code) {
  if (code->IsCode()) {
    int entry =
        Heap::non_monomorphic_cache()->FindNumberEntry(
            Code::cast(code)->flags());
    // The entry must be present see comment in ProbeCache.
    ASSERT(entry != -1);
    ASSERT(Heap::non_monomorphic_cache()->ValueAt(entry) ==
           Heap::undefined_value());
    Heap::non_monomorphic_cache()->ValueAtPut(entry, code);
    CHECK(GetProbeValue(Code::cast(code)->flags()) == code);
  }
  return code;
}


Code* StubCache::FindCallInitialize(int argc) {
  Code::Flags flags =
      Code::ComputeFlags(Code::CALL_IC, UNINITIALIZED, NORMAL, argc);
  Object* result = ProbeCache(flags);
  ASSERT(!result->IsUndefined());
  // This might be called during the marking phase of the collector
  // hence the unchecked cast.
  return reinterpret_cast<Code*>(result);
}


Object* StubCache::ComputeCallInitialize(int argc) {
  Code::Flags flags =
      Code::ComputeFlags(Code::CALL_IC, UNINITIALIZED, NORMAL, argc);
  Object* probe = ProbeCache(flags);
  if (!probe->IsUndefined()) return probe;
  StubCompiler compiler;
  return FillCache(compiler.CompileCallInitialize(flags));
}


Object* StubCache::ComputeCallPreMonomorphic(int argc) {
  Code::Flags flags =
      Code::ComputeFlags(Code::CALL_IC, PREMONOMORPHIC, NORMAL, argc);
  Object* probe = ProbeCache(flags);
  if (!probe->IsUndefined()) return probe;
  StubCompiler compiler;
  return FillCache(compiler.CompileCallPreMonomorphic(flags));
}


Object* StubCache::ComputeCallNormal(int argc) {
  Code::Flags flags =
      Code::ComputeFlags(Code::CALL_IC, MONOMORPHIC, NORMAL, argc);
  Object* probe = ProbeCache(flags);
  if (!probe->IsUndefined()) return probe;
  StubCompiler compiler;
  return FillCache(compiler.CompileCallNormal(flags));
}


Object* StubCache::ComputeCallMegamorphic(int argc) {
  Code::Flags flags =
      Code::ComputeFlags(Code::CALL_IC, MEGAMORPHIC, NORMAL, argc);
  Object* probe = ProbeCache(flags);
  if (!probe->IsUndefined()) return probe;
  StubCompiler compiler;
  return FillCache(compiler.CompileCallMegamorphic(flags));
}


Object* StubCache::ComputeCallMiss(int argc) {
  Code::Flags flags =
      Code::ComputeFlags(Code::STUB, MEGAMORPHIC, NORMAL, argc);
  Object* probe = ProbeCache(flags);
  if (!probe->IsUndefined()) return probe;
  StubCompiler compiler;
  return FillCache(compiler.CompileCallMiss(flags));
}


Object* StubCache::ComputeCallDebugBreak(int argc) {
  Code::Flags flags =
      Code::ComputeFlags(Code::CALL_IC, DEBUG_BREAK, NORMAL, argc);
  Object* probe = ProbeCache(flags);
  if (!probe->IsUndefined()) return probe;
  StubCompiler compiler;
  return FillCache(compiler.CompileCallDebugBreak(flags));
}


Object* StubCache::ComputeCallDebugPrepareStepIn(int argc) {
  Code::Flags flags =
      Code::ComputeFlags(Code::CALL_IC, DEBUG_PREPARE_STEP_IN, NORMAL, argc);
  Object* probe = ProbeCache(flags);
  if (!probe->IsUndefined()) return probe;
  StubCompiler compiler;
  return FillCache(compiler.CompileCallDebugPrepareStepIn(flags));
}


Object* StubCache::ComputeLazyCompile(int argc) {