RFR: 8302873: ZGC: dump barrier data in C2 Mach nodes

[Tobias Hartmann]

On Wed, 22 Feb 2023 09:46:45 GMT, Roberto Castañeda Lozano <rcastanedalo at openjdk.org> wrote:

>> src/hotspot/share/gc/shared/c2/barrierSetC2.hpp line 309:
>> 
>>> 307: #ifndef PRODUCT
>>> 308:   virtual void dump_barrier_data(const MachNode* mach, outputStream* st) const {
>>> 309:     st->print("%x", mach->barrier_data());
>> 
>> Just wondering, do we ever have barrier data without ZGC?
>
> No, this is just a generic fallback implementation in case other GCs want to adopt ZGC's very late barrier expansion model. Would you prefer to remove the `st->print` statement? Either way is fine by me.

I was wondering if we should add `Unimplemented()` instead but I don't have a strong opinion either and leave that to you.

-------------

PR: https://git.openjdk.org/jdk/pull/12662