[lworld] RFR: 8366705: [lworld] Re-work of arrays meta-data [v4]

[Frederic Parain]

On Wed, 3 Sep 2025 16:11:54 GMT, Coleen Phillimore <coleenp at openjdk.org> wrote:

>> Frederic Parain has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 67 commits:
>> 
>>  - Merge branch 'array_klasses' of github.com:fparain/valhalla into array_klasses
>>  - Forgot a TODO
>>  - Small cleanup
>>  - Merge remote-tracking branch 'upstream/lworld' into array_klasses
>>  - Moved get_Klass() back to protected and updated usages
>>  - Merge branch 'array_klasses' of github.com:fparain/valhalla into array_klasses
>>  - Linked TODOs to JDK-8366668
>>  - Multidim array fix
>>  - Cleanup T_FLAT_ELEMENT related code
>>  - Fix for isAssignableFrom + tests
>>  - ... and 57 more: https://git.openjdk.org/valhalla/compare/22e9d5f5...527a17b6
>
> make/test/BuildMicrobenchmark.gmk line 97:
> 
>> 95:         --add-exports java.base/jdk.internal.misc=ALL-UNNAMED \
>> 96:         --add-exports java.base/jdk.internal.util=ALL-UNNAMED \
>> 97: 				--add-exports java.base/jdk.internal.value=ALL-UNNAMED \
> 
> Indentation?  I hope I got the number of spaces right.
> Suggestion:
> 
>         --add-exports java.base/jdk.internal.value=ALL-UNNAMED \

Fixed.

> src/hotspot/share/classfile/javaClasses.cpp line 1137:
> 
>> 1135:   if (vmClasses::Class_klass_loaded()) {
>> 1136: 
>> 1137:     if (k->is_refArray_klass() || k->is_flatArray_klass()) {
> 
> There was a is_refined_objArray_klass() method added that I think can be used here.

Fixed.

> src/hotspot/share/classfile/javaClasses.cpp line 1246:
> 
>> 1244:   } else {
>> 1245:     ObjArrayKlass* objarray_k = (ObjArrayKlass*)as_Klass(m);
>> 1246:     // Mirror is either an ObjArrayKlass or one of its refined array klasses
> 
> This is a confusing comment.  Refined array klasses don't have their own mirrors.  Maybe:
> 
> Suggestion:
> 
>     // Mirror should be restored for an ObjArrayKlass or one of its refined array klasses.

Fixed.

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

PR Review Comment: https://git.openjdk.org/valhalla/pull/1452#discussion_r2322936201
PR Review Comment: https://git.openjdk.org/valhalla/pull/1452#discussion_r2322944149
PR Review Comment: https://git.openjdk.org/valhalla/pull/1452#discussion_r2322950221