8346923: MetaspaceShared base calculation may cause overflow in align_up

[calvinccheung]

This fix adds overflow detection in MetaspaceShared::compute_shared_base before calling align_up. It is needed in order to work with the proposed changes for JDK-8318127 which will add an assert to check for overflow.

Passed tiers 1 - 4 testing.

---

Progress

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Issue

• JDK-8346923: MetaspaceShared base calculation may cause overflow in align_up (Enhancement - P4)

Reviewers

• Ioi Lam (@iklam - Reviewer)
• Matias Saavedra Silva (@matias9927 - Reviewer)

Reviewing

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[bridgekeeper]

👋 Welcome back ccheung! 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]

@calvinccheung 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:

8346923: MetaspaceShared base calculation may cause overflow in align_up

Reviewed-by: iklam, matsaave

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 238 new commits pushed to the master branch:

• 21feef3: 8348239: SA does not know about DeoptimizeObjectsALotThread
• 8cc1304: 8287788: Implement a better allocator for downcalls
• 039e73f: 8346736: Java Security Standard Algorithm Names spec should include key algorithm names
• aba60a9: 8189441: Define algorithm names for keys derived from KeyAgreement
• 03106eb: 8344119: CUPSPrinter does not respect PostScript printer definition specification in case of reading ImageableArea values from PPD files
• ad01dfb: 8346920: Serial: Support allocation in old generation when heap is almost full
• 1d8ccb8: 8342465: Improve API documentation for java.lang.classfile
• 7d6055a: 8348429: Update cross-compilation devkits to Fedora 41/gcc 13.2
• f1e0797: 8348586: Optionally silence make warnings about non-control variables
• ffeb9b5: 8342807: Update links in java.base to use https://
• ... and 228 more: https://git.openjdk.org/jdk/compare/46ba515c4989de7545d409570315274e0ea1c5ac...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.

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

[openjdk]

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[mlbridge]

Webrevs

• 00: Full (4bc510f3)

[iklam]

Looks good to me.

[matias9927]

LGTM!

[calvinccheung]

Thanks @iklam and @matias9927 for the review.

/integrate

[openjdk]

Going to push as commit 1916a77.
Since your change was applied there have been 238 commits pushed to the master branch:

• 21feef3: 8348239: SA does not know about DeoptimizeObjectsALotThread
• 8cc1304: 8287788: Implement a better allocator for downcalls
• 039e73f: 8346736: Java Security Standard Algorithm Names spec should include key algorithm names
• aba60a9: 8189441: Define algorithm names for keys derived from KeyAgreement
• 03106eb: 8344119: CUPSPrinter does not respect PostScript printer definition specification in case of reading ImageableArea values from PPD files
• ad01dfb: 8346920: Serial: Support allocation in old generation when heap is almost full
• 1d8ccb8: 8342465: Improve API documentation for java.lang.classfile
• 7d6055a: 8348429: Update cross-compilation devkits to Fedora 41/gcc 13.2
• f1e0797: 8348586: Optionally silence make warnings about non-control variables
• ffeb9b5: 8342807: Update links in java.base to use https://
• ... and 228 more: https://git.openjdk.org/jdk/compare/46ba515c4989de7545d409570315274e0ea1c5ac...master

Your commit was automatically rebased without conflicts.

[openjdk]

@calvinccheung Pushed as commit 1916a77.

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