RFR: 8304996: Add missing HandleMarks [v2]

[David Holmes]

On Wed, 29 Mar 2023 08:39:53 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

> I think the issue synopsis should be capitalized: "Add missing HandleMarks". Also, does it cover the cases that were not covered by `dump_at_exit` `HandleMark` before? If not, then it is not adding "missing" HMs.

Fixed capitalization in HandleMark.

Not sure what your issue is with "missing" - the HM's were not present where the Handles were used and hence were missing. Some cases were directly detected by removing the old HM in `dump_for_exit` but I also checked those files for other cases and added them.

> src/hotspot/share/oops/klassVtable.cpp line 1178:
> 
>> 1176: 
>> 1177:   assert(_size_method_table == supers->length(), "wrong size");
>> 1178:   HandleMark hm(THREAD);
> 
> Question: Would this make the handles area grow up to `_size_method_table` in the worst case? I thought we want to have `HandleMark`-s closer to actual handle creation/last-use to keep the footprint at bay.

I was optimising for runtime performance rather than footprint, but you are right this could grow in a way we don't want. So I reverted this change and made a similar change to `klassVtable::check_constraints`.

Thanks for looking at this @shipilev .

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PR Comment: https://git.openjdk.org/jdk/pull/13215#issuecomment-1489362742
PR Review Comment: https://git.openjdk.org/jdk/pull/13215#discussion_r1152511587