[PATCH] Simplification proposal regarding TYPE-field initialization in primitive wrappers

[Сергей Цыпанов]

Hello,

> I suspect that it will print null, because to my knowledge, int.class will be compiled to a getstatic Integer.TYPE, so your test basically tests if Integer.TYPE == Integer.TYPE.

right, Remi pointed this out in his response.

> Also, do the tier1 tests succeed with your patch?

I'm going to do that as far as my work station is fixed, hope tomorrow. Apparently, something is going to go wrong :) Anyway, I'll notify about results when this is done.

Regards,
Sergey Tsypanov


26.11.2019, 21:57, "Johannes Kuhn" <info at j-kuhn.de>:
> On November 26, 2019 8:29:06 PM GMT+01:00, "Сергей Цыпанов" <sergei.tsypanov at yandex.ru> wrote:
>> Hello,
>>
>> while using java.lang.Integer.TYPE I've found out that currently
>> wrapper classes for primitives initialize their own TYPE-fields by
>> calling native method java.lang.Class.getPrimitiveClass().
>>
>> This can be simplified by changing existing declaration (here for
>> java.lang.Integer)
>>
>> @SuppressWarnings("unchecked")
>> public static final Class<Integer> TYPE = (Class<Integer>)
>> Class.getPrimitiveClass("int");
>>
>> to
>>
>> public static final Class<Integer> TYPE = int.class;
>>
>> This is likely to improve start-up time as Class.getPrimitiveClass() is
>> called 9 times (8 primitive type wrappers + java.lang.Void), after the
>> change this method is not called at all and thus can be removed along
>> with its backing C++ code on VM-side. The fields are initialized purely
>> on Java side.
>>
>> I've verified correctness of the substitution with this test run on JDK
>> 11
>>
>> @Test
>> void name() {
>>   assert void.class == Void.TYPE;
>>   assert boolean.class == Boolean.TYPE;
>>   assert byte.class == Byte.TYPE;
>>   assert char.class == Character.TYPE;
>>   assert short.class == Short.TYPE;
>>   assert int.class == Integer.TYPE;
>>   assert long.class == Long.TYPE;
>>   assert float.class == Float.TYPE;
>>   assert double.class == Double.TYPE;
>> }
>>
>> The patch is attached.
>>
>> Regards,
>> Sergey Tsypanov
>
> Hi,
> a few questions:
> What does System.out.println(int.class); with your patch print? "int" or "null"?
>
> I suspect that it will print null, because to my knowledge, int.class will be compiled to a getstatic Integer.TYPE, so your test basically tests if Integer.TYPE == Integer.TYPE.
>
> Also, do the tier1 tests succeed with your patch?
>
> With best regards,
> Johannes