RFR: 8293979: Resolve JVM_CONSTANT_Class references at CDS dump time [v4]

[Calvin Cheung]

On Wed, 19 Oct 2022 18:39:25 GMT, Ioi Lam <iklam at openjdk.org> wrote:

>> Some `JVM_CONSTANT_Class` entries are guaranteed to resolve to the same value at both CDS dump time and run time:
>> 
>> - Classes that are resolved during `vmClasses::resolve_all()`. These classes cannot be replaced by JVMTI agents at run time.
>> - Supertypes -- at run time, a class `C` can be loaded from the CDS archive only if all of `C`'s super types are also loaded from the CDS archive. Therefore, we know that a `JVM_CONSTANT_Class` reference to a supertype of `C` must resolved to the same value at both CDS dump time and run time.
>> 
>> By doing the resolution at dump time, we can speed up run time start-up by a little bit.
>> 
>> The `ClassPrelinker` class added by this PR will also be used in future REFs for pre-resolving other constant pool entries. The ultimate goal is to resolve `invokedynamic` and `invokehandle` so we can significantly improve the start-up time of features such as Lambda expressions and String concatenation. See [JDK-8293336](https://bugs.openjdk.org/browse/JDK-8293336)
>
> 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 six additional commits since the last revision:
> 
>  - @coleenp comments: changed to AllStatic
>  - Merge branch 'master' into 8293979-resolve-class-references-at-dumptime
>  - fixed product build
>  - @coleenp comments
>  - Merge branch 'master' into 8293979-resolve-class-references-at-dumptime
>  - 8293979: Resolve JVM_CONSTANT_Class references at CDS dump time

Looks good. Just one nit in constantPool.cpp.

src/hotspot/share/oops/constantPool.cpp line 376:

> 374:   set_resolved_references(OopHandle());
> 375: 
> 376:   bool archived = false;

I think this declaration could be moved to line 392 since it is only used in that case.

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Marked as reviewed by ccheung (Reviewer).

PR: https://git.openjdk.org/jdk/pull/10330