[api] Make ObjectTemplate::SetNativeDataProperty() work even if the ObjectTemplate does not have a …

src/api-natives.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/api-natives.h"
 
 #include "src/api.h"
 #include "src/isolate-inl.h"
 #include "src/lookup.h"
 #include "src/messages.h"
@@ skipping 130 matching lines @@
   switch (intrinsic) {
 #define GET_INTRINSIC_VALUE(name, iname) \
   case v8::k##name:                      \
     return native_context->iname();
     V8_INTRINSICS_LIST(GET_INTRINSIC_VALUE)
 #undef GET_INTRINSIC_VALUE
   }
   return nullptr;
 }
 
+// Returns parent function template or null.
+FunctionTemplateInfo* GetParent(FunctionTemplateInfo* data) {
+  Object* parent = data->parent_template();
+  return parent->IsUndefined() ? nullptr : FunctionTemplateInfo::cast(parent);
+}
 
+// Starting from given object template's constructor walk up the inheritance
+// chain till a function template that has an instance template is found.
+ObjectTemplateInfo* GetParent(ObjectTemplateInfo* data) {
+  Object* maybe_ctor = data->constructor();
+  if (maybe_ctor->IsUndefined()) return nullptr;
+  FunctionTemplateInfo* ctor = FunctionTemplateInfo::cast(maybe_ctor);
+  while (true) {
+    ctor = GetParent(ctor);
+    if (ctor == nullptr) return nullptr;
+    Object* maybe_obj = ctor->instance_template();
+    if (!maybe_obj->IsUndefined()) return ObjectTemplateInfo::cast(maybe_obj);
+  }
+}
+
+template <typename TemplateInfoT>
 MaybeHandle<JSObject> ConfigureInstance(Isolate* isolate, Handle<JSObject> obj,
-                                        Handle<TemplateInfo> data) {
+                                        Handle<TemplateInfoT> data) {
+  HandleScope scope(isolate);
+  // Disable access checks while instantiating the object.
+  AccessCheckDisableScope access_check_scope(isolate, obj);
+
+  if (i::FLAG_new_api_accessors) {
+    // Walk the inheritance chain and copy all accessors to current object.
+    int max_number_of_properties = 0;
+    TemplateInfoT* info = *data;
+    while (info != nullptr) {
+      if (!info->property_accessors()->IsUndefined()) {
+        Object* props = info->property_accessors();
+        if (!props->IsUndefined()) {
+          Handle<Object> props_handle(props, isolate);
+          NeanderArray props_array(props_handle);
+          max_number_of_properties += props_array.length();
+        }
+      }
+      info = GetParent(info);
+    }
+
+    if (max_number_of_properties > 0) {
+      int valid_descriptors = 0;
+      // Use a temporary FixedArray to accumulate unique accessors.
+      Handle<FixedArray> array =
+          isolate->factory()->NewFixedArray(max_number_of_properties);
+
+      info = *data;
+      while (info != nullptr) {
+        // Accumulate static accessors
+        if (!info->property_accessors()->IsUndefined()) {
+          Handle<Object> props(info->property_accessors(), isolate);
+          valid_descriptors =
+              AccessorInfo::AppendUnique(props, array, valid_descriptors);
+        }
+        info = GetParent(info);
+      }
+
+      // Install accumulated static accessors.
+      for (int i = 0; i < valid_descriptors; i++) {
+        Handle<AccessorInfo> accessor(AccessorInfo::cast(array->get(i)));
+        JSObject::SetAccessor(obj, accessor).Assert();
+      }
+    }
+  }
+
   auto property_list = handle(data->property_list(), isolate);
   if (property_list->IsUndefined()) return obj;
   // TODO(dcarney): just use a FixedArray here.
   NeanderArray properties(property_list);
   if (properties.length() == 0) return obj;
-  HandleScope scope(isolate);
-  // Disable access checks while instantiating the object.
-  AccessCheckDisableScope access_check_scope(isolate, obj);
 
   int i = 0;
   for (int c = 0; c < data->number_of_properties(); c++) {
     auto name = handle(Name::cast(properties.get(i++)), isolate);
     auto bit = handle(properties.get(i++), isolate);
     if (bit->IsSmi()) {
       PropertyDetails details(Smi::cast(*bit));
       PropertyAttributes attributes = details.attributes();
       PropertyKind kind = details.kind();
 
@@ skipping 23 matching lines @@
       auto prop_data = handle(GetIntrinsic(isolate, intrinsic), isolate);
 
       RETURN_ON_EXCEPTION(isolate, DefineDataProperty(isolate, obj, name,
                                                       prop_data, attributes),
                           JSObject);
     }
   }
   return obj;
 }
 
+void CacheTemplateInstantiation(Isolate* isolate, Handle<Smi> serial_number,
+                                Handle<JSObject> object) {
+  auto cache = isolate->template_instantiations_cache();
+  auto new_cache = ObjectHashTable::Put(cache, serial_number, object);
+  isolate->native_context()->set_template_instantiations_cache(*new_cache);
+}
+
+void UnacheTemplateInstantiation(Isolate* isolate, Handle<Smi> serial_number) {

[Toon Verwaest, 2016/01/29 14:37:45]

Unache? :)

[Igor Sheludko, 2016/02/01 20:43:55]

Done.

+  auto cache = isolate->template_instantiations_cache();
+  bool was_present = false;
+  auto new_cache = ObjectHashTable::Remove(cache, serial_number, &was_present);
+  DCHECK(was_present);
+  isolate->native_context()->set_template_instantiations_cache(*new_cache);
+}
+
 MaybeHandle<JSObject> InstantiateObject(Isolate* isolate,
                                         Handle<ObjectTemplateInfo> info) {
   // Enter a new scope.  Recursion could otherwise create a lot of handles.
   HandleScope scope(isolate);
   // Fast path.
   Handle<JSObject> result;
   auto constructor = handle(info->constructor(), isolate);
   Handle<JSFunction> cons;
   if (constructor->IsUndefined()) {
     cons = isolate->object_function();
   } else {
     auto cons_templ = Handle<FunctionTemplateInfo>::cast(constructor);
     ASSIGN_RETURN_ON_EXCEPTION(
         isolate, cons, InstantiateFunction(isolate, cons_templ), JSFunction);
   }
+  auto serial_number = handle(Smi::cast(info->serial_number()), isolate);
+  if (serial_number->value()) {
+    // Probe cache.
+    auto cache = isolate->template_instantiations_cache();
+    Object* boilerplate = cache->Lookup(serial_number);
+    if (boilerplate->IsJSObject()) {
+      result = handle(JSObject::cast(boilerplate), isolate);
+      result = JSObject::DeepCopy(result, JSObject::kObjectIsShallow)

[Toon Verwaest, 2016/01/29 14:37:45]

Object templates can contain object templates as data properties, so the object
isn't necessarily shallow right? See DefineDataProperty.

[Igor Sheludko, 2016/02/01 20:43:55]

Done. Thanks for noticing!

+                   .ToHandleChecked();

[Toon Verwaest, 2016/01/29 14:37:45]

Note that this only works because all AccessorPairs on Object templates contain
cached FunctionTemplates... ;)

[Igor Sheludko, 2016/02/01 20:43:55]

It could actually fail here if the stack is almost over.

+      return scope.CloseAndEscape(result);
+    }
+  }
   auto object = isolate->factory()->NewJSObject(cons);
   ASSIGN_RETURN_ON_EXCEPTION(
       isolate, result, ConfigureInstance(isolate, object, info), JSFunction);
   // TODO(dcarney): is this necessary?
   JSObject::MigrateSlowToFast(result, 0, "ApiNatives::InstantiateObject");
+
+  if (serial_number->value()) {
+    CacheTemplateInstantiation(isolate, serial_number, result);
+    result = JSObject::DeepCopy(result, JSObject::kObjectIsShallow)
+                 .ToHandleChecked();
+  }
   return scope.CloseAndEscape(result);
 }
 
 
-void CacheFunction(Isolate* isolate, Handle<Smi> serial_number,
-                   Handle<JSFunction> function) {
-  auto cache = isolate->function_cache();
-  auto new_cache = ObjectHashTable::Put(cache, serial_number, function);
-  isolate->native_context()->set_function_cache(*new_cache);
-}
-
-
-void UncacheFunction(Isolate* isolate, Handle<Smi> serial_number) {
-  auto cache = isolate->function_cache();
-  bool was_present = false;
-  auto new_cache = ObjectHashTable::Remove(cache, serial_number, &was_present);
-  DCHECK(was_present);
-  isolate->native_context()->set_function_cache(*new_cache);
-}
-
-
 MaybeHandle<JSFunction> InstantiateFunction(Isolate* isolate,
                                             Handle<FunctionTemplateInfo> data,
                                             Handle<Name> name) {
   auto serial_number = handle(Smi::cast(data->serial_number()), isolate);
-  // Probe cache.
-  if (!data->do_not_cache()) {
-    auto cache = isolate->function_cache();
+  if (serial_number->value()) {
+    // Probe cache.
+    auto cache = isolate->template_instantiations_cache();
     Object* element = cache->Lookup(serial_number);
     if (element->IsJSFunction()) {
       return handle(JSFunction::cast(element), isolate);
     }
   }
   // Enter a new scope.  Recursion could otherwise create a lot of handles.
   HandleScope scope(isolate);
   Handle<JSObject> prototype;
   if (!data->remove_prototype()) {
     auto prototype_templ = handle(data->prototype_template(), isolate);
@@ skipping 24 matching lines @@
       MAYBE_RETURN(JSObject::SetPrototype(prototype, parent_prototype, false,
                                           Object::THROW_ON_ERROR),
                    MaybeHandle<JSFunction>());
     }
   }
   auto function = ApiNatives::CreateApiFunction(
       isolate, data, prototype, ApiNatives::JavaScriptObjectType);
   if (!name.is_null() && name->IsString()) {
     function->shared()->set_name(*name);
   }
-  if (!data->do_not_cache()) {
+  if (serial_number->value()) {
     // Cache the function.
-    CacheFunction(isolate, serial_number, function);
+    CacheTemplateInstantiation(isolate, serial_number, function);
   }
   auto result = ConfigureInstance(isolate, function, data);
   if (result.is_null()) {
     // Uncache on error.
-    if (!data->do_not_cache()) {
-      UncacheFunction(isolate, serial_number);
+    if (serial_number->value()) {
+      UnacheTemplateInstantiation(isolate, serial_number);
     }
     return MaybeHandle<JSFunction>();
   }
   return scope.CloseAndEscape(function);
 }
 
 
 class InvokeScope {
  public:
   explicit InvokeScope(Isolate* isolate)
@@ skipping 43 matching lines @@
 
 
 MaybeHandle<JSObject> ApiNatives::InstantiateObject(
     Handle<ObjectTemplateInfo> data) {
   Isolate* isolate = data->GetIsolate();
   InvokeScope invoke_scope(isolate);
   return ::v8::internal::InstantiateObject(isolate, data);
 }
 
 
-MaybeHandle<FunctionTemplateInfo> ApiNatives::ConfigureInstance(
-    Isolate* isolate, Handle<FunctionTemplateInfo> desc,
-    Handle<JSObject> instance) {
-  // Configure the instance by adding the properties specified by the
-  // instance template.
-  if (desc->instance_template()->IsUndefined()) return desc;
-  InvokeScope invoke_scope(isolate);
-  Handle<ObjectTemplateInfo> instance_template(
-      ObjectTemplateInfo::cast(desc->instance_template()), isolate);
-  RETURN_ON_EXCEPTION(isolate, ::v8::internal::ConfigureInstance(
-                                   isolate, instance, instance_template),
-                      FunctionTemplateInfo);
-  return desc;
-}
-
-
 void ApiNatives::AddDataProperty(Isolate* isolate, Handle<TemplateInfo> info,
                                  Handle<Name> name, Handle<Object> value,
                                  PropertyAttributes attributes) {
   const int kSize = 3;
   PropertyDetails details(attributes, DATA, 0, PropertyCellType::kNoCell);
   auto details_handle = handle(details.AsSmi(), isolate);
   Handle<Object> data[kSize] = {name, details_handle, value};
   AddPropertyToPropertyList(isolate, info, kSize, data);
 }
 
@@ skipping 147 matching lines @@
   if (!obj->indexed_property_handler()->IsUndefined()) {
     map->set_has_indexed_interceptor();
   }
 
   // Mark instance as callable in the map.
   if (!obj->instance_call_handler()->IsUndefined()) {
     map->set_is_callable();
     map->set_is_constructor(true);
   }
 
-  // Recursively copy parent instance templates' accessors,
-  // 'data' may be modified.
-  int max_number_of_additional_properties = 0;
-  int max_number_of_static_properties = 0;
-  FunctionTemplateInfo* info = *obj;
-  while (true) {
-    if (!info->instance_template()->IsUndefined()) {
-      Object* props = ObjectTemplateInfo::cast(info->instance_template())
-                          ->property_accessors();
-      if (!props->IsUndefined()) {
-        Handle<Object> props_handle(props, isolate);
-        NeanderArray props_array(props_handle);
-        max_number_of_additional_properties += props_array.length();
+  if (!i::FLAG_new_api_accessors) {
+    // Recursively copy parent instance templates' accessors,
+    // 'data' may be modified.
+    int max_number_of_additional_properties = 0;
+    int max_number_of_static_properties = 0;
+    FunctionTemplateInfo* info = *obj;
+    while (true) {
+      if (!i::FLAG_new_api_accessors &&
+          !info->instance_template()->IsUndefined()) {
+        Object* props = ObjectTemplateInfo::cast(info->instance_template())
+                            ->property_accessors();
+        if (!props->IsUndefined()) {
+          Handle<Object> props_handle(props, isolate);
+          NeanderArray props_array(props_handle);
+          max_number_of_additional_properties += props_array.length();
+        }
       }
+      if (!info->property_accessors()->IsUndefined()) {
+        Object* props = info->property_accessors();
+        if (!props->IsUndefined()) {
+          Handle<Object> props_handle(props, isolate);
+          NeanderArray props_array(props_handle);
+          max_number_of_static_properties += props_array.length();
+        }
+      }
+      Object* parent = info->parent_template();
+      if (parent->IsUndefined()) break;
+      info = FunctionTemplateInfo::cast(parent);
     }
-    if (!info->property_accessors()->IsUndefined()) {
-      Object* props = info->property_accessors();
-      if (!props->IsUndefined()) {
-        Handle<Object> props_handle(props, isolate);
-        NeanderArray props_array(props_handle);
-        max_number_of_static_properties += props_array.length();
+
+    Map::EnsureDescriptorSlack(map, max_number_of_additional_properties);
+
+    // Use a temporary FixedArray to acculumate static accessors
+    int valid_descriptors = 0;
+    Handle<FixedArray> array;
+    if (max_number_of_static_properties > 0) {
+      array =
+          isolate->factory()->NewFixedArray(max_number_of_static_properties);
+    }
+
+    while (true) {
+      // Install instance descriptors
+      if (!i::FLAG_new_api_accessors &&
+          !obj->instance_template()->IsUndefined()) {
+        Handle<ObjectTemplateInfo> instance = Handle<ObjectTemplateInfo>(
+            ObjectTemplateInfo::cast(obj->instance_template()), isolate);
+        Handle<Object> props =
+            Handle<Object>(instance->property_accessors(), isolate);
+        if (!props->IsUndefined()) {
+          Map::AppendCallbackDescriptors(map, props);
+        }
       }
+      // Accumulate static accessors
+      if (!obj->property_accessors()->IsUndefined()) {
+        Handle<Object> props =
+            Handle<Object>(obj->property_accessors(), isolate);
+        valid_descriptors =
+            AccessorInfo::AppendUnique(props, array, valid_descriptors);
+      }
+      // Climb parent chain
+      Handle<Object> parent = Handle<Object>(obj->parent_template(), isolate);
+      if (parent->IsUndefined()) break;
+      obj = Handle<FunctionTemplateInfo>::cast(parent);
     }
-    Object* parent = info->parent_template();
-    if (parent->IsUndefined()) break;
-    info = FunctionTemplateInfo::cast(parent);
-  }
 
-  Map::EnsureDescriptorSlack(map, max_number_of_additional_properties);
-
-  // Use a temporary FixedArray to acculumate static accessors
-  int valid_descriptors = 0;
-  Handle<FixedArray> array;
-  if (max_number_of_static_properties > 0) {
-    array = isolate->factory()->NewFixedArray(max_number_of_static_properties);
-  }
-
-  while (true) {
-    // Install instance descriptors
-    if (!obj->instance_template()->IsUndefined()) {
-      Handle<ObjectTemplateInfo> instance = Handle<ObjectTemplateInfo>(
-          ObjectTemplateInfo::cast(obj->instance_template()), isolate);
-      Handle<Object> props =
-          Handle<Object>(instance->property_accessors(), isolate);
-      if (!props->IsUndefined()) {
-        Map::AppendCallbackDescriptors(map, props);
-      }
+    // Install accumulated static accessors
+    for (int i = 0; i < valid_descriptors; i++) {
+      Handle<AccessorInfo> accessor(AccessorInfo::cast(array->get(i)));
+      JSObject::SetAccessor(result, accessor).Assert();
     }
-    // Accumulate static accessors
-    if (!obj->property_accessors()->IsUndefined()) {
-      Handle<Object> props = Handle<Object>(obj->property_accessors(), isolate);
-      valid_descriptors =
-          AccessorInfo::AppendUnique(props, array, valid_descriptors);
-    }
-    // Climb parent chain
-    Handle<Object> parent = Handle<Object>(obj->parent_template(), isolate);
-    if (parent->IsUndefined()) break;
-    obj = Handle<FunctionTemplateInfo>::cast(parent);
-  }
-
-  // Install accumulated static accessors
-  for (int i = 0; i < valid_descriptors; i++) {
-    Handle<AccessorInfo> accessor(AccessorInfo::cast(array->get(i)));
-    JSObject::SetAccessor(result, accessor).Assert();
   }
 
   DCHECK(result->shared()->IsApiFunction());
   return result;
 }
 
 }  // namespace internal
 }  // namespace v8