RFR: 8331341: secondary_super_cache does not scale well: C1 and interpreter [v23]

[Dean Long]

On Thu, 10 Oct 2024 01:07:01 GMT, Dean Long <dlong at openjdk.org> wrote:

>> Andrew Haley has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 61 commits:
>> 
>>  - Merge from 4ff72dc57e65e99b129f0ba28196994edf402018
>>  - Fix s390
>>  - Use post-incrememnt RegSet operator.
>>  - Merge branch 'clean' into JDK-8331658-work
>>  - Fix merge
>>  - Merge branch 'clean' into JDK-8331658-work
>>  - Merge from JDK head.
>>  - Cleanup
>>  - Fix shared code
>>  - Fix shared code
>>  - ... and 51 more: https://git.openjdk.org/jdk/compare/4ff72dc5...a7612674
>
> src/hotspot/share/oops/klass.cpp line 193:
> 
>> 191: 
>> 192:   // The check at the start of this function guarantees there are 0s
>> 193:   // in the bitmap, so this loop eventually terminates.
> 
> I don't see the check that this comment is referring to.

I guess it means the check at line 184, which on the surface doesn't involve the bitmap at all, but I guess there is a directly relationship between secondary_supers()->length() and the bitmap.  It wouldn't hurt to spell this out more clearly.

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

PR Review Comment: https://git.openjdk.org/jdk/pull/19989#discussion_r1794441800