Canvas2D Performance: fix the bottleneck of hasInstance during JS binding -- overloading

Source/bindings/templates/methods.cpp

 {##############################################################################}
 {% macro generate_method(method, world_suffix) %}
 {% filter conditional(method.conditional_string) %}
 static void {{method.name}}{{method.overload_index}}Method{{world_suffix}}(const v8::FunctionCallbackInfo<v8::Value>& info)
 {
     {# Local variables #}
     {% if method.has_exception_state %}
     ExceptionState exceptionState(ExceptionState::ExecutionContext, "{{method.name}}", "{{interface_name}}", info.Holder(), info.GetIsolate());
     {% endif %}
     {# Overloaded methods have length checked during overload resolution #}
@@ skipping 91 matching lines @@
     {{cpp_method_call(method, argument.v8_set_return_value_for_main_world, argument.cpp_value) | indent}}
     {% else %}
     {{cpp_method_call(method, argument.v8_set_return_value, argument.cpp_value) | indent}}
     {% endif %}
     {% if argument.has_event_listener_argument %}
     {{hidden_dependency_action(method.name) | indent}}
     {% endif %}
     return;
 }
 {% endif %}
-{% if argument.has_type_checking_interface and not argument.is_variadic_wrapper_type %}
+{% if argument.has_type_checking_interface and not argument.is_variadic_wrapper_type and not argument.type_checked_already %}

[Nils Barth (inactive), 2014/10/13 14:36:57]

Line break please.

[yunchao, 2014/10/14 06:58:49]

Done.

 {# Type checking for wrapper interface types (if interface not implemented,
    throw a TypeError), per http://www.w3.org/TR/WebIDL/#es-interface
    Note: for variadic arguments, the type checking is done for each matched
    argument instead; see argument.is_variadic_wrapper_type code-path below. #}
 if (info.Length() > {{argument.index}} && {% if argument.is_nullable %}!isUndefinedOrNull(info[{{argument.index}}]) && {% endif %}!V8{{argument.idl_type}}::hasInstance(info[{{argument.index}}], info.GetIsolate())) {
     {{throw_type_error(method, '"parameter %s is not of type \'%s\'."' %
                                (argument.index + 1, argument.idl_type)) | indent}}
     return;
 }
 {% endif %}{# argument.has_type_checking_interface #}
@@ skipping 493 matching lines @@
   if method.is_per_world_bindings else '0' %}
 {% set property_attribute =
   'static_cast<v8::PropertyAttribute>(%s)' % ' | '.join(method.property_attributes)
   if method.property_attributes else 'v8::None' %}
 {% set only_exposed_to_private_script = 'V8DOMConfiguration::OnlyExposedToPrivateScript' if method.only_exposed_to_private_script else 'V8DOMConfiguration::ExposedToAllScripts' %}
 static const V8DOMConfiguration::MethodConfiguration {{method.name}}MethodConfiguration = {
     "{{method.name}}", {{method_callback}}, {{method_callback_for_main_world}}, {{method.length}}, {{only_exposed_to_private_script}},
 };
 V8DOMConfiguration::installMethod({{method.function_template}}, {{method.signature}}, {{property_attribute}}, {{method.name}}MethodConfiguration, isolate);
 {%- endmacro %}