RFR 8223110 [lworld] Handle GC that happens when C1 allocates buffered value objects

[Tobias Hartmann]

Hi Ioi,

looks good to me.

Thanks,
Tobias

On 02.05.19 00:33, Ioi Lam wrote:
> https://bugs.openjdk.java.net/browse/JDK-8223110
> http://cr.openjdk.java.net/~iklam/valhalla/8223110-gc-while-buffering-objs-in-c1-vep.v01/
> 
> Here's a small fix that properly scans oops on the callstack when GC happens while the C1 entry
> points allocate buffered instances of inlined classes.
> 
> I also fixed a related bug in CompiledMethod::preserve_callee_argument_oops where we should use the
> scalarized calling convention only for C2-compiled methods.
> 
> With this patch, C1 can basically handle incoming scalarized parameters. There are still some bugs
> that I need to fix (see commented out cases in TestCallingConventionC1.java). I'll also start
> working on returning scalarized values from C1-compiled methods.
> 
> Thanks
> - Ioi