RFR (S): 8198561: Make oop and narrowOop always have their own class type

[Roman Kennke]

This is a very welcome change!
Changeset looks good to me (except I've no idea what the sparc part
does). Same question as Colleen though.

Thanks,
Roman

On Mon, Feb 26, 2018 at 8:55 PM,  <coleen.phillimore at oracle.com> wrote:
>
> Hi Erik,
>
> This looks great.   I assume that the generated code (for these classes vs.
> oopDesc* and juint) comes out the same?
>
> thanks,
> Coleen
>
>
> On 2/26/18 8:32 AM, Erik Österlund wrote:
>>
>> Hi,
>>
>> Making oop sometimes map to class types and sometimes to primitives comes
>> with some unfortunate problems. Advantages of making them always have their
>> own type include:
>>
>> 1) Not getting compilation errors in configuration X but not Y
>> 2) Making it easier to adopt existing code to use Shenandoah equals
>> barriers
>> 3) Recognize oops and narrowOops safely in template
>>
>> Therefore, I would like to make both oop and narrowOop always map to a
>> class type consistently.
>>
>> Webrev:
>> http://cr.openjdk.java.net/~eosterlund/8198561/webrev.00/
>>
>> Bug:
>> https://bugs.openjdk.java.net/browse/JDK-8198561
>>
>> Thanks,
>> /Erik
>
>