Rewrite GetPropertyAttribute to use the LookupIterator

src/objects.cc

 // Copyright 2013 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/v8.h"
 
 #include "src/accessors.h"
 #include "src/allocation-site-scopes.h"
 #include "src/api.h"
 #include "src/arguments.h"
@@ skipping 125 matching lines @@
       case LookupIterator::JSPROXY:
         return JSProxy::GetPropertyWithHandler(
             it->GetJSProxy(), it->GetReceiver(), it->name());
       case LookupIterator::INTERCEPTOR: {
         MaybeHandle<Object> maybe_result = JSObject::GetPropertyWithInterceptor(
             it->GetHolder(), it->GetReceiver(), it->name());
         if (!maybe_result.is_null()) return maybe_result;
         if (it->isolate()->has_pending_exception()) return maybe_result;
         break;
       }
-      case LookupIterator::ACCESS_CHECK: {
+      case LookupIterator::ACCESS_CHECK:
         if (it->HasAccess(v8::ACCESS_GET)) break;
         return JSObject::GetPropertyWithFailedAccessCheck(it);
-      }
       case LookupIterator::PROPERTY:
         if (it->HasProperty()) {
           switch (it->property_kind()) {
             case LookupIterator::ACCESSOR:
               return GetPropertyWithAccessor(
                   it->GetReceiver(), it->name(),
                   it->GetHolder(), it->GetAccessors());
             case LookupIterator::DATA:
               return it->GetDataValue();
           }
@@ skipping 400 matching lines @@
   Handle<Object> argv[] = { value };
   RETURN_ON_EXCEPTION(
       isolate,
       Execution::Call(isolate, setter, receiver, ARRAY_SIZE(argv), argv),
       Object);
   return value;
 }
 
 
 static bool FindAllCanReadHolder(LookupIterator* it) {
+  it->skip_interceptor();
+  it->skip_access_checks();

[Igor Sheludko, 2014/06/12 13:27:53]

Naming suggestions:
1) either skip_interceptorS() or skip_access_check()
2) consider renaming to set_skip_XXX()

   for (; it->IsFound(); it->Next()) {
     if (it->state() == LookupIterator::PROPERTY &&
         it->HasProperty() &&
         it->property_kind() == LookupIterator::ACCESSOR) {
       Handle<Object> accessors = it->GetAccessors();
       if (accessors->IsAccessorInfo()) {
         if (AccessorInfo::cast(*accessors)->all_can_read()) return true;
       } else if (accessors->IsAccessorPair()) {
         if (AccessorPair::cast(*accessors)->all_can_read()) return true;
       }
     }
   }
   return false;
 }
 
 
 MaybeHandle<Object> JSObject::GetPropertyWithFailedAccessCheck(
     LookupIterator* it) {
   Handle<JSObject> checked = Handle<JSObject>::cast(it->GetHolder());
   if (FindAllCanReadHolder(it)) {
     return GetPropertyWithAccessor(
         it->GetReceiver(), it->name(), it->GetHolder(), it->GetAccessors());
   }
   it->isolate()->ReportFailedAccessCheck(checked, v8::ACCESS_GET);
   RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(it->isolate(), Object);
   return it->factory()->undefined_value();
 }
 
 
-PropertyAttributes JSObject::GetPropertyAttributeWithFailedAccessCheck(
-    Handle<JSObject> object,
-    LookupResult* result,
-    Handle<Name> name,
-    bool check_prototype) {
-  LookupIterator::Configuration configuration = check_prototype
-      ? LookupIterator::CHECK_DERIVED
-      : LookupIterator::CHECK_OWN_REAL;
-  LookupIterator it(object, name, object, configuration);
-  if (FindAllCanReadHolder(&it)) return it.property_details().attributes();
-  it.isolate()->ReportFailedAccessCheck(object, v8::ACCESS_HAS);
+PropertyAttributes JSObject::GetPropertyAttributesWithFailedAccessCheck(
+    LookupIterator* it) {
+  Handle<JSObject> checked = Handle<JSObject>::cast(it->GetHolder());
+  if (FindAllCanReadHolder(it)) return it->property_details().attributes();
+  it->isolate()->ReportFailedAccessCheck(checked, v8::ACCESS_HAS);
   // TODO(yangguo): Issue 3269, check for scheduled exception missing?
   return ABSENT;
 }
 
 
 static bool FindAllCanWriteHolder(LookupResult* result,
                                   Handle<Name> name,
                                   bool check_prototype) {
   if (result->IsInterceptor()) {
     result->holder()->LookupOwnRealNamedProperty(name, result);
@@ skipping 2442 matching lines @@
   LookupResult result(isolate);
   object->LookupRealNamedPropertyInPrototypes(name, &result);
   if (result.IsFound()) {
     switch (result.type()) {
       case NORMAL:
       case FIELD:
       case CONSTANT:
         *done = result.IsReadOnly();
         break;
       case INTERCEPTOR: {
-        PropertyAttributes attr = GetPropertyAttributeWithInterceptor(
-            handle(result.holder()), object, name, true);
+        LookupIterator it(object, name, handle(result.holder()));
+        PropertyAttributes attr = GetPropertyAttributes(&it);
         *done = !!(attr & READ_ONLY);
         break;
       }
       case CALLBACKS: {
         *done = true;
         if (!result.IsReadOnly()) {
           Handle<Object> callback_object(result.GetCallbackObject(), isolate);
           return SetPropertyWithCallback(object, name, value,
                                          handle(result.holder()),
                                          callback_object, strict_mode);
@@ skipping 636 matching lines @@
 
 
 MaybeHandle<Object> JSProxy::DeleteElementWithHandler(
     Handle<JSProxy> proxy, uint32_t index, DeleteMode mode) {
   Isolate* isolate = proxy->GetIsolate();
   Handle<String> name = isolate->factory()->Uint32ToString(index);
   return JSProxy::DeletePropertyWithHandler(proxy, name, mode);
 }
 
 
-PropertyAttributes JSProxy::GetPropertyAttributeWithHandler(
+PropertyAttributes JSProxy::GetPropertyAttributesWithHandler(
     Handle<JSProxy> proxy,
-    Handle<JSReceiver> receiver,
+    Handle<Object> receiver,
     Handle<Name> name) {
   Isolate* isolate = proxy->GetIsolate();
   HandleScope scope(isolate);
 
   // TODO(rossberg): adjust once there is a story for symbols vs proxies.
   if (name->IsSymbol()) return ABSENT;
 
   Handle<Object> args[] = { name };
   Handle<Object> result;
   ASSIGN_RETURN_ON_EXCEPTION_VALUE(
@@ skipping 61 matching lines @@
   return static_cast<PropertyAttributes>(attributes);
 }
 
 
 PropertyAttributes JSProxy::GetElementAttributeWithHandler(
     Handle<JSProxy> proxy,
     Handle<JSReceiver> receiver,
     uint32_t index) {
   Isolate* isolate = proxy->GetIsolate();
   Handle<String> name = isolate->factory()->Uint32ToString(index);
-  return GetPropertyAttributeWithHandler(proxy, receiver, name);
+  return GetPropertyAttributesWithHandler(proxy, receiver, name);
 }
 
 
 void JSProxy::Fix(Handle<JSProxy> proxy) {
   Isolate* isolate = proxy->GetIsolate();
 
   // Save identity hash.
   Handle<Object> hash(proxy->GetIdentityHash(), isolate);
 
   if (proxy->IsJSFunctionProxy()) {
@@ skipping 521 matching lines @@
       } else if (value_changed) {
         EnqueueChangeRecord(object, "update", name, old_value);
       }
     }
   }
 
   return value;
 }
 
 
-PropertyAttributes JSObject::GetPropertyAttributePostInterceptor(
-    Handle<JSObject> object,
-    Handle<JSObject> receiver,
-    Handle<Name> name,
-    bool check_prototype) {
-  // Check own property, ignore interceptor.
-  Isolate* isolate = object->GetIsolate();
-  LookupResult result(isolate);
-  object->LookupOwnRealNamedProperty(name, &result);
-  if (result.IsFound()) return result.GetAttributes();
+Maybe<PropertyAttributes> JSObject::GetPropertyAttributesWithInterceptor(
+    Handle<JSObject> holder,
+    Handle<Object> receiver,
+    Handle<Name> name) {
+  // TODO(rossberg): Support symbols in the API.
+  if (name->IsSymbol()) return Maybe<PropertyAttributes>(ABSENT);
 
-  if (check_prototype) {
-    // Continue searching via the prototype chain.
-    Handle<Object> proto(object->GetPrototype(), isolate);
-    if (!proto->IsNull()) {
-      return JSReceiver::GetPropertyAttributeWithReceiver(
-          Handle<JSObject>::cast(proto), receiver, name);
+  Isolate* isolate = holder->GetIsolate();
+  HandleScope scope(isolate);
+
+  // Make sure that the top context does not change when doing
+  // callbacks or interceptor calls.
+  AssertNoContextChange ncc(isolate);
+
+  Handle<InterceptorInfo> interceptor(holder->GetNamedInterceptor());
+  PropertyCallbackArguments args(
+      isolate, interceptor->data(), *receiver, *holder);
+  if (!interceptor->query()->IsUndefined()) {
+    v8::NamedPropertyQueryCallback query =
+        v8::ToCData<v8::NamedPropertyQueryCallback>(interceptor->query());
+    LOG(isolate,
+        ApiNamedPropertyAccess("interceptor-named-has", *holder, *name));
+    v8::Handle<v8::Integer> result =
+        args.Call(query, v8::Utils::ToLocal(Handle<String>::cast(name)));
+    if (!result.IsEmpty()) {
+      ASSERT(result->IsInt32());
+      return Maybe<PropertyAttributes>(
+          static_cast<PropertyAttributes>(result->Int32Value()));
+    }
+  } else if (!interceptor->getter()->IsUndefined()) {
+    v8::NamedPropertyGetterCallback getter =
+        v8::ToCData<v8::NamedPropertyGetterCallback>(interceptor->getter());
+    LOG(isolate,
+        ApiNamedPropertyAccess("interceptor-named-get-has", *holder, *name));
+    v8::Handle<v8::Value> result =
+        args.Call(getter, v8::Utils::ToLocal(Handle<String>::cast(name)));
+    if (!result.IsEmpty()) return Maybe<PropertyAttributes>(DONT_ENUM);
+  }
+  return Maybe<PropertyAttributes>();
+}
+
+
+PropertyAttributes JSReceiver::GetOwnPropertyAttributes(
+    Handle<JSReceiver> object, Handle<Name> name) {
+  // Check whether the name is an array index.
+  uint32_t index = 0;
+  if (object->IsJSObject() && name->AsArrayIndex(&index)) {
+    return GetOwnElementAttribute(object, index);
+  }
+  LookupIterator it(object, name, LookupIterator::CHECK_OWN);
+  return GetPropertyAttributes(&it);
+}
+
+
+PropertyAttributes JSReceiver::GetPropertyAttributes(LookupIterator* it) {
+  for (; it->IsFound(); it->Next()) {
+    switch (it->state()) {
+      case LookupIterator::NOT_FOUND:
+        UNREACHABLE();
+      case LookupIterator::JSPROXY:
+        return JSProxy::GetPropertyAttributesWithHandler(
+            it->GetJSProxy(), it->GetReceiver(), it->name());
+      case LookupIterator::INTERCEPTOR: {
+        Maybe<PropertyAttributes> result =
+            JSObject::GetPropertyAttributesWithInterceptor(
+                it->GetHolder(), it->GetReceiver(), it->name());
+        if (result.has_value) return result.value;
+        break;
+      }
+      case LookupIterator::ACCESS_CHECK:
+        if (it->HasAccess(v8::ACCESS_HAS)) break;
+        return JSObject::GetPropertyAttributesWithFailedAccessCheck(it);
+      case LookupIterator::PROPERTY:
+        if (it->HasProperty()) return it->property_details().attributes();
+        break;
     }
   }
   return ABSENT;
 }
 
 
-PropertyAttributes JSObject::GetPropertyAttributeWithInterceptor(
-    Handle<JSObject> object,
-    Handle<JSObject> receiver,
-    Handle<Name> name,
-    bool check_prototype) {
-  // TODO(rossberg): Support symbols in the API.
-  if (name->IsSymbol()) return ABSENT;
-
-  Isolate* isolate = object->GetIsolate();
-  HandleScope scope(isolate);
-
-  // Make sure that the top context does not change when doing
-  // callbacks or interceptor calls.
-  AssertNoContextChange ncc(isolate);
-
-  Handle<InterceptorInfo> interceptor(object->GetNamedInterceptor());
-  PropertyCallbackArguments args(
-      isolate, interceptor->data(), *receiver, *object);
-  if (!interceptor->query()->IsUndefined()) {
-    v8::NamedPropertyQueryCallback query =
-        v8::ToCData<v8::NamedPropertyQueryCallback>(interceptor->query());
-    LOG(isolate,
-        ApiNamedPropertyAccess("interceptor-named-has", *object, *name));
-    v8::Handle<v8::Integer> result =
-        args.Call(query, v8::Utils::ToLocal(Handle<String>::cast(name)));
-    if (!result.IsEmpty()) {
-      ASSERT(result->IsInt32());
-      return static_cast<PropertyAttributes>(result->Int32Value());
-    }
-  } else if (!interceptor->getter()->IsUndefined()) {
-    v8::NamedPropertyGetterCallback getter =
-        v8::ToCData<v8::NamedPropertyGetterCallback>(interceptor->getter());
-    LOG(isolate,
-        ApiNamedPropertyAccess("interceptor-named-get-has", *object, *name));
-    v8::Handle<v8::Value> result =
-        args.Call(getter, v8::Utils::ToLocal(Handle<String>::cast(name)));
-    if (!result.IsEmpty()) return DONT_ENUM;
-  }
-  return GetPropertyAttributePostInterceptor(
-      object, receiver, name, check_prototype);
-}
-
-
-PropertyAttributes JSReceiver::GetPropertyAttributeWithReceiver(
-    Handle<JSReceiver> object,
-    Handle<JSReceiver> receiver,
-    Handle<Name> key) {
-  uint32_t index = 0;
-  if (object->IsJSObject() && key->AsArrayIndex(&index)) {
-    return JSObject::GetElementAttributeWithReceiver(
-        Handle<JSObject>::cast(object), receiver, index, true);
-  }
-  // Named property.
-  LookupResult lookup(object->GetIsolate());
-  object->Lookup(key, &lookup);
-  return GetPropertyAttributeForResult(object, receiver, &lookup, key, true);
-}
-
-
-PropertyAttributes JSReceiver::GetPropertyAttributeForResult(
-    Handle<JSReceiver> object,
-    Handle<JSReceiver> receiver,
-    LookupResult* lookup,
-    Handle<Name> name,
-    bool check_prototype) {
-  // Check access rights if needed.
-  if (object->IsAccessCheckNeeded()) {
-    Heap* heap = object->GetHeap();
-    Handle<JSObject> obj = Handle<JSObject>::cast(object);
-    if (!heap->isolate()->MayNamedAccess(obj, name, v8::ACCESS_HAS)) {
-      return JSObject::GetPropertyAttributeWithFailedAccessCheck(
-          obj, lookup, name, check_prototype);
-    }
-  }
-  if (lookup->IsFound()) {
-    switch (lookup->type()) {
-      case NORMAL:  // fall through
-      case FIELD:
-      case CONSTANT:
-      case CALLBACKS:
-        return lookup->GetAttributes();
-      case HANDLER: {
-        return JSProxy::GetPropertyAttributeWithHandler(
-            handle(lookup->proxy()), receiver, name);
-      }
-      case INTERCEPTOR:
-        return JSObject::GetPropertyAttributeWithInterceptor(
-            handle(lookup->holder()),
-            Handle<JSObject>::cast(receiver),
-            name,
-            check_prototype);
-      case NONEXISTENT:
-        UNREACHABLE();
-    }
-  }
-  return ABSENT;
-}
-
-
-PropertyAttributes JSReceiver::GetOwnPropertyAttribute(
-    Handle<JSReceiver> object, Handle<Name> name) {
-  // Check whether the name is an array index.
-  uint32_t index = 0;
-  if (object->IsJSObject() && name->AsArrayIndex(&index)) {
-    return GetOwnElementAttribute(object, index);
-  }
-  // Named property.
-  LookupResult lookup(object->GetIsolate());
-  object->LookupOwn(name, &lookup, true);
-  return GetPropertyAttributeForResult(object, object, &lookup, name, false);
-}
-
-
 PropertyAttributes JSObject::GetElementAttributeWithReceiver(
     Handle<JSObject> object,
     Handle<JSReceiver> receiver,
     uint32_t index,
     bool check_prototype) {
   Isolate* isolate = object->GetIsolate();
 
   // Check access rights if needed.
   if (object->IsAccessCheckNeeded()) {
     if (!isolate->MayIndexedAccess(object, index, v8::ACCESS_HAS)) {
@@ skipping 653 matching lines @@
   if (inline_value->IsUndefined() || inline_value->IsSmi()) return;
 
   Handle<ObjectHashTable> hashtable(ObjectHashTable::cast(inline_value));
   bool was_present = false;
   ObjectHashTable::Remove(hashtable, key, &was_present);
 }
 
 
 bool JSObject::HasHiddenProperties(Handle<JSObject> object) {
   Handle<Name> hidden = object->GetIsolate()->factory()->hidden_string();
-  return GetPropertyAttributePostInterceptor(
-      object, object, hidden, false) != ABSENT;
+  LookupIterator it(object, hidden, LookupIterator::CHECK_OWN_REAL);
+  return GetPropertyAttributes(&it) != ABSENT;
 }
 
 
 Object* JSObject::GetHiddenPropertiesHashTable() {
   ASSERT(!IsJSGlobalProxy());
   if (HasFastProperties()) {
     // If the object has fast properties, check whether the first slot
     // in the descriptor array matches the hidden string. Since the
     // hidden strings hash code is zero (and no other name has hash
     // code zero) it will always occupy the first entry if present.
@@ skipping 794 matching lines @@
         }
       }
     } else {
       Handle<FixedArray> names =
           isolate->factory()->NewFixedArray(copy->NumberOfOwnProperties());
       copy->GetOwnPropertyNames(*names, 0);
       for (int i = 0; i < names->length(); i++) {
         ASSERT(names->get(i)->IsString());
         Handle<String> key_string(String::cast(names->get(i)));
         PropertyAttributes attributes =
-            JSReceiver::GetOwnPropertyAttribute(copy, key_string);
+            JSReceiver::GetOwnPropertyAttributes(copy, key_string);
         // Only deep copy fields from the object literal expression.
         // In particular, don't try to copy the length attribute of
         // an array.
         if (attributes != NONE) continue;
         Handle<Object> value =
             Object::GetProperty(copy, key_string).ToHandleChecked();
         if (value->IsJSObject()) {
           Handle<JSObject> result;
           ASSIGN_RETURN_ON_EXCEPTION(
               isolate, result,
@@ skipping 11116 matching lines @@
 #define ERROR_MESSAGES_TEXTS(C, T) T,
   static const char* error_messages_[] = {
       ERROR_MESSAGES_LIST(ERROR_MESSAGES_TEXTS)
   };
 #undef ERROR_MESSAGES_TEXTS
   return error_messages_[reason];
 }
 
 
 } }  // namespace v8::internal