Fast string construct stub (ia32 only for now).

src/bootstrapper.cc

 // Copyright 2006-2008 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 702 matching lines @@
                         Top::initial_object_prototype(), Builtins::Illegal,
                         true);
     global_context()->set_boolean_function(*boolean_fun);
   }
 
   {  // --- S t r i n g ---
     Handle<JSFunction> string_fun =
         InstallFunction(global, "String", JS_VALUE_TYPE, JSValue::kSize,
                         Top::initial_object_prototype(), Builtins::Illegal,
                         true);
+    string_fun->shared()->set_construct_stub(
+        Builtins::builtin(Builtins::StringConstructCode));
     global_context()->set_string_function(*string_fun);
     // Add 'length' property to strings.
     Handle<DescriptorArray> string_descriptors =
         Factory::CopyAppendProxyDescriptor(
             Factory::empty_descriptor_array(),
             Factory::length_symbol(),
             Factory::NewProxy(&Accessors::StringLength),
             static_cast<PropertyAttributes>(DONT_ENUM |
                                             DONT_DELETE |
                                             READ_ONLY));
@@ skipping 1096 matching lines @@
 }
 
 
 // Restore statics that are thread local.
 char* BootstrapperActive::RestoreState(char* from) {
   nesting_ = *reinterpret_cast<int*>(from);
   return from + sizeof(nesting_);
 }
 
 } }  // namespace v8::internal