8341242: Shenandoah: LRB node is not matched as GC barrier after JDK-8340183

[shipilev]

JDK-8340183 introduced a regression: ShenandoahBarrierSetC2::is_gc_barrier_node is now answering false for the actual ShenandoahLoadReferenceBarrierNode. The fix reinstates the check for LRB node.

Additional testing:

• Linux x86_64 server fastdebug, hotspot_gc_shenandoah
• Linux x86_64 server fastdebug, jdk/jfr/api/consumer/ (100x) -- used to fail intermittently, now it does not

---

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Issue

• JDK-8341242: Shenandoah: LRB node is not matched as GC barrier after JDK-8340183 (Bug - P4)

Reviewers

• Roman Kennke (@rkennke - Reviewer)
• Paul Hohensee (@phohensee - Reviewer)

Reviewing

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[openjdk]

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

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

8341242: Shenandoah: LRB node is not matched as GC barrier after JDK-8340183

Reviewed-by: rkennke, phh

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At the time when this comment was updated there had been 3 new commits pushed to the master branch:

• a6b3188: 8337632: AES-GCM Algorithm optimization for x86_64
• 5586f83: 8341064: Define anchor point and index term for "wrapper classes"
• 4168faf: 8341100: Add index entries for terms used in java.lang.Class

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[openjdk]

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

• hotspot-gc
• shenandoah

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[mlbridge]

Webrevs

• 00: Full (bc2d671c)

[rkennke]

Looks good!

[shipilev]

Thanks! Trivial, right? Restores the code to previous shape.

[shipilev]

/integrate

[openjdk]

Going to push as commit 684d246.
Since your change was applied there have been 14 commits pushed to the master branch:

• 7cc7c08: 8337493: [JVMCI] Number of libgraal threads might be too low
• f7c7958: 8340420: ZGC: Should call vm_shutdown_during_initialization if initialization fails
• 2dc3b1a: 8341201: Broken link in AbstractAnnotationValueVisitor7 due to extra quotation mark
• ad5ffcc: 8341168: Cleanup dead code after JDK-8322630
• 1b46fea: 8341024: [test] build/AbsPathsInImage.java fails with OOM when using ubsan-enabled binaries
• 9bd4785: 8340437: Open source few more AWT Frame related tests
• 988f13a: 8340354: Open source AWT desktop properties and print related tests
• b11066b: 8340719: Open source AWT List tests
• a32c3b4: 8340407: Open source a few more Component related tests
• 31858fc: 8340491: Thread stack-base assertion should report which thread has the un-set stack
• ... and 4 more: https://git.openjdk.org/jdk/compare/f1bf469b4ee07b48b629a126111e307d3cab7fd7...master

Your commit was automatically rebased without conflicts.

[openjdk]

@shipilev Pushed as commit 684d246.

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