8389846: GenShen: ShenandoahScanRemembered::process_clusters may miss dirty cards when use write table

[earthling-amzn]

Clean backport. Fixes heap heap corruption bug in Shenandoah's generational mode.

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Progress

• Change must not contain extraneous whitespace
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• JDK-8389846 needs maintainer approval

Issue

• JDK-8389846: GenShen: ShenandoahScanRemembered::process_clusters may miss dirty cards when use write table (Bug - P2 - Requested)

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[bridgekeeper]

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[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.

[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.

[mlbridge]

Webrevs

• 00: Full (d07c75dd)

[earthling-amzn]

/approval request This change fixes a rare condition in which two GC threads both expect the other to complete an object scan, where in actuality, neither worker performs the scan. This may result in a stale reference pointing into recycled memory, likely causing a crash.

[openjdk]

@earthling-amzn
8389846: The approval request has been created successfully.