8365071: ARM32: JFR intrinsic jvm_commit triggers C2 regalloc assert

[bulasevich]

On 32-bit ARM, the jvm_commit JFR intrinsic builder feeds null (RegP) into a TypeLong Phi, causing mixed long/pointer register sizing and triggering the C2 register allocator assert(_num_regs == reg || !_num_regs).

The fix is trivial: use an appropriate ConL constant instead. This has no effect on 64-bit systems (the generated assembly is identical) but resolves a JFR issue on 32-bit systems.

---

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Issue

• JDK-8365071: ARM32: JFR intrinsic jvm_commit triggers C2 regalloc assert (Bug - P3)

Reviewers

• Markus Grönlund (@mgronlun - Reviewer)

Reviewing

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👋 Welcome back bulasevich! 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]

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

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

8365071: ARM32: JFR intrinsic jvm_commit triggers C2 regalloc assert

Reviewed-by: mgronlun

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At the time when this comment was updated there had been 123 new commits pushed to the master branch:

• 285adff: 8362448: Make use of the Double.toString(double) algorithm in java.text.DecimalFormat
• c9ecedd: 8365594: Strengthen Universe klasses asserts to catch bootstrapping errors earlier
• 2a16cc8: 8365550: JFR: The active-settings view should not use LAST_BATCH
• ... and 120 more: https://git.openjdk.org/jdk/compare/72d1066ae385ce511a70e762ed68afaa72e96ec4...master

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[bulasevich]

@mgronlun You might be interested in this

[mlbridge]

Webrevs

• 00: Full (b961ded6)

[mgronlun]

Looks good.

[bulasevich]

Thanks!
/integrate

[openjdk]

Going to push as commit f2f7a49.
Since your change was applied there have been 127 commits pushed to the master branch:

• e04a310: 8364806: Test sun/security/krb5/config/IncludeRandom.java times out on Windows
• ec7361e: 8365660: test/jdk/sun/security/pkcs11/KeyAgreement/ tests skipped without SkipExceprion
• a005301: 8364780: Unicode extension clarifications for NumberFormat/DecimalFormatSymbols
• ... and 124 more: https://git.openjdk.org/jdk/compare/72d1066ae385ce511a70e762ed68afaa72e96ec4...master

Your commit was automatically rebased without conflicts.

[openjdk]

@bulasevich Pushed as commit f2f7a49.

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