8360288: Shenandoah crash at size_given_klass in op_degenerated

[earthling-amzn]

Not clean.

---

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-8360288 needs maintainer approval

Issue

• JDK-8360288: Shenandoah crash at size_given_klass in op_degenerated (Bug - P3 - Requested)

Reviewers

• Paul Hohensee (@phohensee - Reviewer)

Reviewing

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$ git checkout pull/4003

Update a local copy of the PR:
$ git checkout pull/4003
$ git pull https://git.openjdk.org/jdk17u-dev.git pull/4003/head

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$ git pr checkout 4003

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https://git.openjdk.org/jdk17u-dev/pull/4003.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back wkemper! 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

• 00: Full (e658b4ad)

[phohensee]

With respect to 25u backport, looks to be small context diff in shenandoahHeap.hpp, otherwise clean.

[openjdk]

⚠️ @earthling-amzn 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.

[earthling-amzn]

/approval request This change fixes a crash when Shenandoah unloads the class for an unmarked humongous object. The change only affects Shenandoah. We've tested this with jtreg tiers 1-3 with Shenandoah enabled. We have also tested this on various benchmarks: dacapo, specjvm, specjbb, extremem and others.

[openjdk]

@earthling-amzn
8360288: The approval request has been created successfully.