Avoid incremental marking write-barrier when constructing descriptor arrays.

src/bootstrapper.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 358 matching lines @@
 
 Handle<DescriptorArray> Genesis::ComputeFunctionInstanceDescriptor(
     PrototypePropertyMode prototypeMode) {
   Handle<DescriptorArray> descriptors =
       factory()->NewDescriptorArray(prototypeMode == DONT_ADD_PROTOTYPE
                                     ? 4
                                     : 5);
   PropertyAttributes attributes =
       static_cast<PropertyAttributes>(DONT_ENUM | DONT_DELETE | READ_ONLY);
 
+  DescriptorArray::WhitenessWitness witness(*descriptors);
+
   {  // Add length.
     Handle<Foreign> foreign = factory()->NewForeign(&Accessors::FunctionLength);
     CallbacksDescriptor d(*factory()->length_symbol(), *foreign, attributes);
-    descriptors->Set(0, &d);
+    descriptors->Set(0, &d, witness);
   }
   {  // Add name.
     Handle<Foreign> foreign = factory()->NewForeign(&Accessors::FunctionName);
     CallbacksDescriptor d(*factory()->name_symbol(), *foreign, attributes);
-    descriptors->Set(1, &d);
+    descriptors->Set(1, &d, witness);
   }
   {  // Add arguments.
     Handle<Foreign> foreign =
         factory()->NewForeign(&Accessors::FunctionArguments);
     CallbacksDescriptor d(*factory()->arguments_symbol(), *foreign, attributes);
-    descriptors->Set(2, &d);
+    descriptors->Set(2, &d, witness);
   }
   {  // Add caller.
     Handle<Foreign> foreign = factory()->NewForeign(&Accessors::FunctionCaller);
     CallbacksDescriptor d(*factory()->caller_symbol(), *foreign, attributes);
-    descriptors->Set(3, &d);
+    descriptors->Set(3, &d, witness);
   }
   if (prototypeMode != DONT_ADD_PROTOTYPE) {
     // Add prototype.
     if (prototypeMode == ADD_WRITEABLE_PROTOTYPE) {
       attributes = static_cast<PropertyAttributes>(attributes & ~READ_ONLY);
     }
     Handle<Foreign> foreign =
         factory()->NewForeign(&Accessors::FunctionPrototype);
     CallbacksDescriptor d(*factory()->prototype_symbol(), *foreign, attributes);
-    descriptors->Set(4, &d);
+    descriptors->Set(4, &d, witness);
   }
-  descriptors->Sort();
+  descriptors->Sort(witness);
   return descriptors;
 }
 
 
 Handle<Map> Genesis::CreateFunctionMap(PrototypePropertyMode prototype_mode) {
   Handle<Map> map = factory()->NewMap(JS_FUNCTION_TYPE, JSFunction::kSize);
   Handle<DescriptorArray> descriptors =
       ComputeFunctionInstanceDescriptor(prototype_mode);
   map->set_instance_descriptors(*descriptors);
   map->set_function_with_prototype(prototype_mode != DONT_ADD_PROTOTYPE);
@@ skipping 97 matching lines @@
     PrototypePropertyMode prototypeMode,
     Handle<FixedArray> arguments,
     Handle<FixedArray> caller) {
   Handle<DescriptorArray> descriptors =
       factory()->NewDescriptorArray(prototypeMode == DONT_ADD_PROTOTYPE
                                     ? 4
                                     : 5);
   PropertyAttributes attributes = static_cast<PropertyAttributes>(
       DONT_ENUM | DONT_DELETE);
 
+  DescriptorArray::WhitenessWitness witness(*descriptors);
+
   {  // length
     Handle<Foreign> foreign = factory()->NewForeign(&Accessors::FunctionLength);
     CallbacksDescriptor d(*factory()->length_symbol(), *foreign, attributes);
-    descriptors->Set(0, &d);
+    descriptors->Set(0, &d, witness);
   }
   {  // name
     Handle<Foreign> foreign = factory()->NewForeign(&Accessors::FunctionName);
     CallbacksDescriptor d(*factory()->name_symbol(), *foreign, attributes);
-    descriptors->Set(1, &d);
+    descriptors->Set(1, &d, witness);
   }
   {  // arguments
     CallbacksDescriptor d(*factory()->arguments_symbol(),
                           *arguments,
                           attributes);
-    descriptors->Set(2, &d);
+    descriptors->Set(2, &d, witness);
   }
   {  // caller
     CallbacksDescriptor d(*factory()->caller_symbol(), *caller, attributes);
-    descriptors->Set(3, &d);
+    descriptors->Set(3, &d, witness);
   }
 
   // prototype
   if (prototypeMode != DONT_ADD_PROTOTYPE) {
     if (prototypeMode != ADD_WRITEABLE_PROTOTYPE) {
       attributes = static_cast<PropertyAttributes>(attributes | READ_ONLY);
     }
     Handle<Foreign> foreign =
         factory()->NewForeign(&Accessors::FunctionPrototype);
     CallbacksDescriptor d(*factory()->prototype_symbol(), *foreign, attributes);
-    descriptors->Set(4, &d);
+    descriptors->Set(4, &d, witness);
   }
 
-  descriptors->Sort();
+  descriptors->Sort(witness);
   return descriptors;
 }
 
 
 // ECMAScript 5th Edition, 13.2.3
 Handle<JSFunction> Genesis::GetThrowTypeErrorFunction() {
   if (throw_type_error_function.is_null()) {
     Handle<String> name = factory()->LookupAsciiSymbol("ThrowTypeError");
     throw_type_error_function =
       factory()->NewFunctionWithoutPrototype(name, kNonStrictMode);
@@ skipping 364 matching lines @@
                         isolate->initial_object_prototype(),
                         Builtins::kIllegal, true);
     global_context()->set_regexp_function(*regexp_fun);
 
     ASSERT(regexp_fun->has_initial_map());
     Handle<Map> initial_map(regexp_fun->initial_map());
 
     ASSERT_EQ(0, initial_map->inobject_properties());
 
     Handle<DescriptorArray> descriptors = factory->NewDescriptorArray(5);
+    DescriptorArray::WhitenessWitness witness(*descriptors);
     PropertyAttributes final =
         static_cast<PropertyAttributes>(DONT_ENUM | DONT_DELETE | READ_ONLY);
     int enum_index = 0;
     {
       // ECMA-262, section 15.10.7.1.
       FieldDescriptor field(heap->source_symbol(),
                             JSRegExp::kSourceFieldIndex,
                             final,
                             enum_index++);
-      descriptors->Set(0, &field);
+      descriptors->Set(0, &field, witness);
     }
     {
       // ECMA-262, section 15.10.7.2.
       FieldDescriptor field(heap->global_symbol(),
                             JSRegExp::kGlobalFieldIndex,
                             final,
                             enum_index++);
-      descriptors->Set(1, &field);
+      descriptors->Set(1, &field, witness);
     }
     {
       // ECMA-262, section 15.10.7.3.
       FieldDescriptor field(heap->ignore_case_symbol(),
                             JSRegExp::kIgnoreCaseFieldIndex,
                             final,
                             enum_index++);
-      descriptors->Set(2, &field);
+      descriptors->Set(2, &field, witness);
     }
     {
       // ECMA-262, section 15.10.7.4.
       FieldDescriptor field(heap->multiline_symbol(),
                             JSRegExp::kMultilineFieldIndex,
                             final,
                             enum_index++);
-      descriptors->Set(3, &field);
+      descriptors->Set(3, &field, witness);
     }
     {
       // ECMA-262, section 15.10.7.5.
       PropertyAttributes writable =
           static_cast<PropertyAttributes>(DONT_ENUM | DONT_DELETE);
       FieldDescriptor field(heap->last_index_symbol(),
                             JSRegExp::kLastIndexFieldIndex,
                             writable,
                             enum_index++);
-      descriptors->Set(4, &field);
+      descriptors->Set(4, &field, witness);
     }
     descriptors->SetNextEnumerationIndex(enum_index);
-    descriptors->Sort();
+    descriptors->Sort(witness);
 
     initial_map->set_inobject_properties(5);
     initial_map->set_pre_allocated_property_fields(5);
     initial_map->set_unused_property_fields(0);
     initial_map->set_instance_size(
         initial_map->instance_size() + 5 * kPointerSize);
     initial_map->set_instance_descriptors(*descriptors);
     initial_map->set_visitor_id(StaticVisitorBase::GetVisitorId(*initial_map));
 
     // RegExp prototype object is itself a RegExp.
@@ skipping 116 matching lines @@
         GetThrowTypeErrorFunction();
 
     // Install the ThrowTypeError functions.
     callee->set(0, *throw_function);
     callee->set(1, *throw_function);
     caller->set(0, *throw_function);
     caller->set(1, *throw_function);
 
     // Create the descriptor array for the arguments object.
     Handle<DescriptorArray> descriptors = factory->NewDescriptorArray(3);
+    DescriptorArray::WhitenessWitness witness(*descriptors);
     {  // length
       FieldDescriptor d(*factory->length_symbol(), 0, DONT_ENUM);
-      descriptors->Set(0, &d);
+      descriptors->Set(0, &d, witness);
     }
     {  // callee
       CallbacksDescriptor d(*factory->callee_symbol(), *callee, attributes);
-      descriptors->Set(1, &d);
+      descriptors->Set(1, &d, witness);
     }
     {  // caller
       CallbacksDescriptor d(*factory->caller_symbol(), *caller, attributes);
-      descriptors->Set(2, &d);
+      descriptors->Set(2, &d, witness);
     }
-    descriptors->Sort();
+    descriptors->Sort(witness);
 
     // Create the map. Allocate one in-object field for length.
     Handle<Map> map = factory->NewMap(JS_OBJECT_TYPE,
                                       Heap::kArgumentsObjectSizeStrict);
     map->set_instance_descriptors(*descriptors);
     map->set_function_with_prototype(true);
     map->set_prototype(global_context()->object_function()->prototype());
     map->set_pre_allocated_property_fields(1);
     map->set_inobject_properties(1);
 
@@ skipping 538 matching lines @@
 
     // Update map with length accessor from Array and add "index" and "input".
     Handle<Map> array_map(global_context()->js_array_map());
     Handle<DescriptorArray> array_descriptors(
         array_map->instance_descriptors());
     ASSERT_EQ(1, array_descriptors->number_of_descriptors());
 
     Handle<DescriptorArray> reresult_descriptors =
         factory()->NewDescriptorArray(3);
 
-    reresult_descriptors->CopyFrom(0, *array_descriptors, 0);
+    DescriptorArray::WhitenessWitness witness(*reresult_descriptors);
+
+    reresult_descriptors->CopyFrom(0, *array_descriptors, 0, witness);
 
     int enum_index = 0;
     {
       FieldDescriptor index_field(heap()->index_symbol(),
                                   JSRegExpResult::kIndexIndex,
                                   NONE,
                                   enum_index++);
-      reresult_descriptors->Set(1, &index_field);
+      reresult_descriptors->Set(1, &index_field, witness);
     }
 
     {
       FieldDescriptor input_field(heap()->input_symbol(),
                                   JSRegExpResult::kInputIndex,
                                   NONE,
                                   enum_index++);
-      reresult_descriptors->Set(2, &input_field);
+      reresult_descriptors->Set(2, &input_field, witness);
     }
-    reresult_descriptors->Sort();
+    reresult_descriptors->Sort(witness);
 
     initial_map->set_inobject_properties(2);
     initial_map->set_pre_allocated_property_fields(2);
     initial_map->set_unused_property_fields(0);
     initial_map->set_instance_descriptors(*reresult_descriptors);
 
     global_context()->set_regexp_result_map(*initial_map);
   }
 
 #ifdef DEBUG
@@ skipping 540 matching lines @@
   return from + sizeof(NestingCounterType);
 }
 
 
 // Called when the top-level V8 mutex is destroyed.
 void Bootstrapper::FreeThreadResources() {
   ASSERT(!IsActive());
 }
 
 } }  // namespace v8::internal