8330027: Identity hashes of archived objects must be based on a reproducible random seed

[tstuefe]

This fixes an issue with CDS archive reproducibility that can happen under rare circumstances. See original JBS issue for details.

I had to manually resolve the hunk in src/hotspot/share/cds/heapShared.cpp because both

8251330: Reorder CDS archived heap to speed up relocation
8329431: Improve speed of writing CDS heap objects
were missing.

I also had to change CDSConfig::is_dumping_static_archive() - which only exists in JDK 22 and later - to the technically equal DumpSharedSpaces.

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8330027 needs maintainer approval

Issue

• JDK-8330027: Identity hashes of archived objects must be based on a reproducible random seed (Bug - P4)

Reviewers

• Martin Doerr (@TheRealMDoerr - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk21u-dev.git pull/562/head:pull/562
$ git checkout pull/562

Update a local copy of the PR:
$ git checkout pull/562
$ git pull https://git.openjdk.org/jdk21u-dev.git pull/562/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 562

View PR using the GUI difftool:
$ git pr show -t 562

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk21u-dev/pull/562.diff

Webrev

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[bridgekeeper]

👋 Welcome back stuefe! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

This backport pull request has now been updated with issue from the original commit.

[mlbridge]

Webrevs

• 01: Full - Incremental (a2f6ffc5)
• 00: Full (155bb08c)

[TheRealMDoerr]

LGTM. I suggest removing the empty line, too.

[openjdk]

⚠️ @tstuefe This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[tstuefe]

Thanks @TheRealMDoerr !