RFR(S): 8190432 [MVT] Value Types should have a default pre-allocated

[Tobias Hartmann]

Hi Fred,

just hit this build problem on JPRT when trying another patch on top:

/opt/jprt/T/P1/120645.tobias/s/src/hotspot/share/memory/oopFactory.cpp: In static member function 'static arrayOopDesc* 
oopFactory::new_valueArray(Klass*, int, Thread*)':
/opt/jprt/T/P1/120645.tobias/s/src/hotspot/share/memory/oopFactory.cpp:112:45: error: invalid conversion from 'oop' to 
'instanceOop' [-fpermissive]
    instanceOop value = vklass->default_value();

Thanks,
Tobias

On 01.11.2017 09:15, Tobias Hartmann wrote:
> Hi Fred,
> 
> this looks good to me! Some style comments:
> 
> classFileParser.cpp
> - line 1724: whitespace between "index" and "++"
> - line 5770: you can merge the else and the if below
> 
> interpreterRuntime.cpp
> - line 220 and 359: Wouldn't it make sense to move the asserts into ValueKlass::default_value()? Because right now you 
> are only checking at vwithfield and vdefault.
> 
> I've filed JDK-8190458 for the C2 changes.
> 
> Best regards,
> Tobias
> 
> On 31.10.2017 18:35, Frederic Parain wrote:
>> Please review this small changeset to pre-allocate a default value:
>>
>> Bug:
>> https://bugs.openjdk.java.net/browse/JDK-8190432
>>
>> Webrev:
>> http://cr.openjdk.java.net/~fparain/8190432/webrev.00/index.html
>>
>> The changeset injects a static field into each Java mirror of a
>> value type to keep a reference to the pre-allocated value.
>>
>> All hotspot_valhalla tests pass.
>>
>> Thank you,
>>
>> Fred