RFR: 8293337: Store method handle intrinsics in AOT cache [v9]

[Dan Heidinga]

On Mon, 14 Oct 2024 07:21:51 GMT, Ioi Lam <iklam at openjdk.org> wrote:

>> This is the 5th PR for [JEP 483: Ahead-of-Time Class Loading & Linking](https://bugs.openjdk.org/browse/JDK-8315737).
>> 
>> This PR is necessary to support [JDK-8293336: AOT-linking of invokedynamic for lambda expression and string concat](https://bugs.openjdk.org/browse/JDK-8293336), which needs to store Java heap objects that have native pointers to the C++ `Method` objects  returned by `SystemDictionary::find_method_handle_intrinsic()` 
>> 
>> These `Method` objects are created within the JVM. They do not belong to any actual Java classes. We store all these `Method` objects into the AOT cache, so that they can be referenced by other artifacts in the AOT cache.
>> 
>> ---
>> See [here](https://bugs.openjdk.org/browse/JDK-8315737) for the sequence of dependent RFEs for implementing JEP 483.
>
> Ioi Lam has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains 16 additional commits since the last revision:
> 
>  - Merge branch 'jep-483-step-04-8293187-support-sun-invoke-util-wrapper-in-cds-archive-heap' into jep-483-step-05-8293337-archive-method-handle-intrinsics
>  - Merge branch 'jep-483-step-04-8293187-support-sun-invoke-util-wrapper-in-cds-archive-heap' into jep-483-step-05-8293337-archive-method-handle-intrinsics
>  - Merge branch 'jep-483-step-04-8293187-support-sun-invoke-util-wrapper-in-cds-archive-heap' into jep-483-step-05-8293337-archive-method-handle-intrinsics
>  - Merge branch 'jep-483-step-04-8293187-support-sun-invoke-util-wrapper-in-cds-archive-heap' into jep-483-step-05-8293337-archive-method-handle-intrinsics
>  - @coleenp comments
>  - Merge branch 'jep-483-step-04-8293187-support-sun-invoke-util-wrapper-in-cds-archive-heap' into jep-483-step-05-8293337-archive-method-handle-intrinsics
>  - Merge branch 'jep-483-step-04-8293187-support-sun-invoke-util-wrapper-in-cds-archive-heap' into jep-483-step-05-8293337-archive-method-handle-intrinsics
>  - @vnkozlov comment - added NOT_CDS_RETURN
>  - Merge branch 'jep-483-step-04-8293187-support-sun-invoke-util-wrapper-in-cds-archive-heap' into jep-483-step-05-8293337-archive-method-handle-intrinsics
>  - Merge branch 'jep-483-step-04-8293187-support-sun-invoke-util-wrapper-in-cds-archive-heap' into jep-483-step-05-8293337-archive-method-handle-intrinsics
>  - ... and 6 more: https://git.openjdk.org/jdk/compare/20599b63...84777aa4

src/hotspot/share/classfile/systemDictionary.cpp line 2097:

> 2095:     }
> 2096: 
> 2097:     MutexLocker ml(InvokeMethodIntrinsicTable_lock);

Should we take this lock once outside the loop and hold it for the duration rather than taking it just again and again before each add operation?

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PR Review Comment: https://git.openjdk.org/jdk/pull/20959#discussion_r1799694921