8373021: aarch64: MacroAssembler::arrays_equals reads out of bounds

[shipilev]

Fixes the +UCOH regression.

Additional testing:

• GHA

---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8373021 needs maintainer approval

Issue

• JDK-8373021: aarch64: MacroAssembler::arrays_equals reads out of bounds (Bug - P3 - Approved)

Reviewing

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Update a local copy of the PR:
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$ git pull https://git.openjdk.org/jdk26u.git pull/40/head

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[bridgekeeper]

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[openjdk]

@shipilev 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:

8373021: aarch64: MacroAssembler::arrays_equals reads out of bounds

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 6 new commits pushed to the master branch:

• 113f561: 8375598: VM crashes with "assert((labs(val) & 0xFFFFFFFF00000000) == 0 || dest == (address)-1) failed: must be 32bit offset or -1" when using too high value for NonNMethodCodeHeapSize
• 3de44e1: 8375057: Update HarfBuzz to 12.3.2
• b0d6432: 8367994: test/jdk/sun/security/pkcs11/Signature/ tests pass when they should skip
• ... and 3 more: https://git.openjdk.org/jdk26u/compare/714632e896743a59f26ba64c458d8d500e143619...master

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➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[openjdk]

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

[openjdk]

⚠️ @shipilev 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.

[shipilev]

/approval request Fixes the AArch64 bug with +UCOH. The patch is relatively new, only a few weeks old, but it is simple and has no bugtail. We have seen this crash in the wild, so there is user exposure. Applies cleanly. Basic tests pass.

[openjdk]

@shipilev
8373021: The approval request has been created successfully.

[mlbridge]

Webrevs

• 00: Full (1bc5691a)