8354541: Remove Shenandoah post barrier expand loop opts

[JohnTortugo]

Please review this patch to remove Shenandoah post-barrier expand loop optimizations. This optimization was added in the first iteration os Shenandoah barriers. Nowadays, we try to always insert LRB at the earliest place and the impact of these optimizations is minimal; they are also frequent source of bugs.

Tested on OSX Aarch64 & Linux amd64 with JTREG tier1-3.

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Progress

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Issue

• JDK-8354541: Remove Shenandoah post barrier expand loop opts (Bug - P4)

Reviewers

• Aleksey Shipilev (@shipilev - Reviewer)

Reviewing

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[bridgekeeper]

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[openjdk]

@JohnTortugo This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8354541: Remove Shenandoah post barrier expand loop opts

Reviewed-by: shade

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 92 new commits pushed to the master branch:

• 7a107e2: 8351603: Change to GCC 14.2.0 for building on Linux at Oracle
• 84458ec: 8353013: java.net.URI.create(String) may have low performance to scan the host/domain name from URI string when the hostname starts with number
• c3de94c: 8352942: jdk/jfr/startupargs/TestMemoryOptions.java fails with 32-bit build
• ... and 89 more: https://git.openjdk.org/jdk/compare/dc249be2474d8711ca6e92ec139b4b6f0aa92e6e...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

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[openjdk]

@JohnTortugo The following labels will be automatically applied to this pull request:

• hotspot
• shenandoah

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[mlbridge]

Webrevs

• 00: Full (bc1dbaf4)

[shipilev]

Looks OK in principle. This would likely not matter in the future when we switch to late barrier expansion for Shenandoah, following the examples of Z and G1. Have you seen any performance impact at all with this patch?

[JohnTortugo]

/integrate

[openjdk]

@JohnTortugo
Your change (at version bc1dbaf) is now ready to be sponsored by a Committer.

[earthling-amzn]

/sponsor

[openjdk]

Going to push as commit 4eae9b5.
Since your change was applied there have been 123 commits pushed to the master branch:

• 31e293b: 8354552: Open source a few Swing tests
• 3e3dff6: 8354451: Open source some more Swing popup menu tests
• e163a76: 8354106: Clean up and open source KeyEvent related tests (Part 2)
• ... and 120 more: https://git.openjdk.org/jdk/compare/dc249be2474d8711ca6e92ec139b4b6f0aa92e6e...master

Your commit was automatically rebased without conflicts.

[openjdk]

@earthling-amzn @JohnTortugo Pushed as commit 4eae9b5.

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