8278965: crash in SymbolTable::do_lookup

[coleenp]

Please review this small change to hold the refcount of a super class name while calling handle_parallel_super_load. Contrary to what I wrote in JDK-8298061, the refcount in the Placeholder table should never go to one. I can reproduce this with btree012 occasionally, so this fixes this too.

The include in placeholders.hpp is required to make the gtest compiled since placeholders header file has Symbol::maybe_increment_refcount and decrement calls.

Tested with the graal test that failed, and tier1-7.

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Issue

• JDK-8278965: crash in SymbolTable::do_lookup

Reviewers

• David Holmes (@dholmes-ora - Reviewer) ⚠️ Review applies to 3f2bea79
• Frederic Parain (@fparain - Committer)
• Ioi Lam (@iklam - Reviewer)

Reviewing

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[mlbridge]

Webrevs

• 01: Full - Incremental (90f0d989)
• 00: Full (3f2bea79)

[dholmes-ora]

Functional change seems fine. I can't say I can follow the test in detail.

Thanks.

[openjdk]

@coleenp 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:

8278965: crash in SymbolTable::do_lookup

Reviewed-by: dholmes, fparain, iklam

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At the time when this comment was updated there had been 37 new commits pushed to the master branch:

• 4539899: 8301480: Replace NULL with nullptr in os/posix
• 1428db7: 8301224: Replace NULL with nullptr in share/gc/shared/
• c25b4f4: 8301578: Perform output outside synchronization in Module.class
• 5830c03: 8302004: InlineTree should consult replay file in release build
• c8ace48: 8301072: Replace NULL with nullptr in share/oops/
• 1c7b09b: 8302069: javax/management/remote/mandatory/notif/NotifReconnectDeadlockTest.java update
• 837d464: 8302125: Make G1 full gc abort the VM after failing VerifyDuringGC verification
• 723433d: 8302117: IgnoreUnrecognizedVMOptions flag causes failure in ArchiveHeapTestClass
• e245620: 8293198: [vectorapi] Improve the implementation of VectorMask.indexInRange()
• b814cfc: 8178806: Better exception logging in crypto code
• ... and 27 more: https://git.openjdk.org/jdk/compare/873558ee80d741469ade030c732091bead431c46...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.

[fparain]

Looks like a reasonable fix for the issue described in the CR.

[iklam]

LGTM.

[coleenp]

Thank you David, Fred and Ioi!
/integrate

[openjdk]

Going to push as commit 582b943.
Since your change was applied there have been 37 commits pushed to the master branch:

• 4539899: 8301480: Replace NULL with nullptr in os/posix
• 1428db7: 8301224: Replace NULL with nullptr in share/gc/shared/
• c25b4f4: 8301578: Perform output outside synchronization in Module.class
• 5830c03: 8302004: InlineTree should consult replay file in release build
• c8ace48: 8301072: Replace NULL with nullptr in share/oops/
• 1c7b09b: 8302069: javax/management/remote/mandatory/notif/NotifReconnectDeadlockTest.java update
• 837d464: 8302125: Make G1 full gc abort the VM after failing VerifyDuringGC verification
• 723433d: 8302117: IgnoreUnrecognizedVMOptions flag causes failure in ArchiveHeapTestClass
• e245620: 8293198: [vectorapi] Improve the implementation of VectorMask.indexInRange()
• b814cfc: 8178806: Better exception logging in crypto code
• ... and 27 more: https://git.openjdk.org/jdk/compare/873558ee80d741469ade030c732091bead431c46...master

Your commit was automatically rebased without conflicts.

[openjdk]

@coleenp Pushed as commit 582b943.

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