Make Map::Create always use the Object function, and remove the unused inobject properties

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 6642 matching lines @@
 Handle<Map> Map::Copy(Handle<Map> map) {
   Handle<DescriptorArray> descriptors(map->instance_descriptors());
   int number_of_own_descriptors = map->NumberOfOwnDescriptors();
   Handle<DescriptorArray> new_descriptors =
       DescriptorArray::CopyUpTo(descriptors, number_of_own_descriptors);
   return CopyReplaceDescriptors(
       map, new_descriptors, OMIT_TRANSITION, MaybeHandle<Name>());
 }
 
 
-Handle<Map> Map::Create(Handle<JSFunction> constructor,
-                        int extra_inobject_properties) {
-  Handle<Map> copy = Copy(handle(constructor->initial_map()));
+Handle<Map> Map::Create(Isolate* isolate, int inobject_properties) {
+  Handle<Map> copy = Copy(handle(isolate->object_function()->initial_map()));
 
-  // Check that we do not overflow the instance size when adding the
-  // extra inobject properties.
-  int instance_size_delta = extra_inobject_properties * kPointerSize;
-  int max_instance_size_delta =
-      JSObject::kMaxInstanceSize - copy->instance_size();
-  int max_extra_properties = max_instance_size_delta >> kPointerSizeLog2;
+  // Check that we do not overflow the instance size when adding the extra
+  // inobject properties. If the instance size overflows, we allocate as many
+  // properties as we can as inobject properties.
+  int max_extra_properties =
+      (JSObject::kMaxInstanceSize - JSObject::kHeaderSize) >> kPointerSizeLog2;
 
-  // If the instance size overflows, we allocate as many properties as we can as
-  // inobject properties.
-  if (extra_inobject_properties > max_extra_properties) {
-    instance_size_delta = max_instance_size_delta;
-    extra_inobject_properties = max_extra_properties;
+  if (inobject_properties > max_extra_properties) {
+    inobject_properties = max_extra_properties;
   }
 
+  int new_instance_size =
+      JSObject::kHeaderSize + kPointerSize * inobject_properties;
+
   // Adjust the map with the extra inobject properties.
-  int inobject_properties =
-      copy->inobject_properties() + extra_inobject_properties;
   copy->set_inobject_properties(inobject_properties);
   copy->set_unused_property_fields(inobject_properties);
-  copy->set_instance_size(copy->instance_size() + instance_size_delta);
+  copy->set_instance_size(new_instance_size);
   copy->set_visitor_id(StaticVisitorBase::GetVisitorId(*copy));
   return copy;
 }
 
 
 Handle<Map> Map::CopyForFreeze(Handle<Map> map) {
   int num_descriptors = map->NumberOfOwnDescriptors();
   Isolate* isolate = map->GetIsolate();
   Handle<DescriptorArray> new_desc = DescriptorArray::CopyUpToAddAttributes(
       handle(map->instance_descriptors(), isolate), num_descriptors, FROZEN);
@@ skipping 9673 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