RFR(S): 8223965: [lworld] Reflective method invocation does not handle value type returned as fields

[Ioi Lam]

Hi Tobias,

The changes look good to me.

Thanks
- Ioi

On 5/17/19 5:53 AM, Tobias Hartmann wrote:
> Hi,
>
> please review the following patch:
> https://bugs.openjdk.java.net/browse/JDK-8223965
> http://cr.openjdk.java.net/~thartmann/8223965/webrev.00/
>
> If a method is invoked via reflection we first call through the runtime [1] and once the method is
> invoked more than 'sun.reflect.inflationThreshold' times we emit bytecodes to directly call the
> method. Now while the generated bytecodes are fine because they are executed through the interpreter
> (or the JIT), the call stub does not correctly handle (c2 compiled) methods that return a value type
> as fields.
>
> I added the corresponding check and also had to use different registers in the call stub to avoid
> trashing those used by the return convention.
>
> Thanks,
> Tobias
>
> [1] Reflection::invoke_method() -> ... -> StubRoutines::call_stub()