8313421: [JVMCI] avoid locking class loader in CompilerToVM.lookupType

[dougxc]

This PR removes the need to lock the system class loader when converting Class instances for boot and platform classes to ResolvedJavaType objects. Not only is the system class loader a suboptimal loader for resolving these classes but locking it can cause deadlock in some JDK tests (e.g. test/jdk/java/lang/System/LoggerFinder/) when run with -Xcomp. For example, a thread that holds the system class loader lock and triggers a blocking compilation will deadlock with the compiler thread servicing the compilation if the compilation requires calling CompilerToVM.lookupType (which most compilations do).

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Issue

• JDK-8313421: [JVMCI] avoid locking class loader in CompilerToVM.lookupType (Bug - P3)

Reviewers

• Tom Rodriguez (@tkrodriguez - Reviewer)
• Tobias Hartmann (@TobiHartmann - Reviewer)

Reviewing

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[bridgekeeper]

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[openjdk]

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

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[tkrodriguez]

This looks looks like a nice cleanup

[openjdk]

@dougxc 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:

8313421: [JVMCI] avoid locking class loader in CompilerToVM.lookupType

Reviewed-by: never, thartmann

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[mlbridge]

Webrevs

• 01: Full - Incremental (86b6489a)
• 00: Full (c32899db)

[TobiHartmann]

Looks good to me but I'm not an expert in this code.

[dougxc]

Thanks for the reviews.

/integrate

[openjdk]

Going to push as commit 83adaf5.
Since your change was applied there have been 28 commits pushed to the master branch:

• 35b60f9: 8298095: Refine implSpec for SegmentAllocator
• 6dba202: 8313670: Simplify shared lib name handling code in some tests
• 8f28809: 8299790: os::print_hex_dump is racy
• e080a0b: 8311508: ZGC: RAII use of IntelJccErratumAlignment
• 242a2e6: 8308843: Generational ZGC: Remove gc/z/TestHighUsage.java
• c822183: 8313768: Reduce interaction with volatile field in j.u.l.StreamHandler
• cd16158: 8314075: Update JCov version for JDK 22
• c307391: 8307184: Incorrect/inconsistent specification and implementation for Elements.getDocComment
• 593ba2f: 8313693: Introduce an internal utility for the Damerau–Levenshtein distance calculation
• 360f65d: 8314022: Problem-list tests failing with jtreg 7.3
• ... and 18 more: https://git.openjdk.org/jdk/compare/5c3041ce838cbfcfb87ce29ff969f627e6f5ceae...master

Your commit was automatically rebased without conflicts.

[openjdk]

@dougxc Pushed as commit 83adaf5.

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