8300968: Accessorize raw oop load in DeadCounterClosure

[fisk]

The DeadCounterClosure class uses raw loads to check for dead phantom oop* entries. This isn't completely GC independent (because generational ZGC colours null pointers as well). We should accessorize this access so that all GCs become happy.

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Issue

• JDK-8300968: Accessorize raw oop load in DeadCounterClosure

Reviewers

• Thomas Schatzl (@tschatzl - Reviewer)
• Stefan Karlsson (@stefank - Reviewer)

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[mlbridge]

Webrevs

• 00: Full (36afe2ca)

[tschatzl]

lgtm.

[openjdk]

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

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8300968: Accessorize raw oop load in DeadCounterClosure

Reviewed-by: tschatzl, stefank

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At the time when this comment was updated there had been 58 new commits pushed to the master branch:

• 48152ef: 8287134: HttpURLConnection chunked streaming mode doesn't enforce specified size
• 4b0e656: 8298118: split-if optimization causes empty loop to temporarily have more than one phi
• 252621d: 8301063: Remove dead code from GrowableArray
• b5a4744: 8300857: State return value for Types.asElement(NoType) explicitly
• 7e951f4: 8301092: Add benchmark for CRC32
• adcfd25: 8301098: Remove dead code FileMapInfo::stop_sharing_and_unmap()
• 9f0887e: 8296661: Typo Found In CSSParser.java
• ccf2f58: 8300806: Update googletest to v1.13.0
• edf1e1a: 8300592: ASan build does not correctly propagate options to some test launchers
• e80b5ea: 8299635: Hotspot update for deprecated sprintf in Xcode 14
• ... and 48 more: https://git.openjdk.org/jdk/compare/5a4945c0d95423d0ab07762c915e9cb4d3c66abb...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.

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[fisk]

lgtm.

Thanks for the review!

[fisk]

Thanks for the review, @stefank!

[fisk]

/integrate

[openjdk]

Going to push as commit 973f741.
Since your change was applied there have been 69 commits pushed to the master branch:

• 64ddf95: 8299858: [Metrics] Swap memory limit reported incorrectly when too large
• 28545dc: 8300247: Harden C1 xchg on AArch64 and PPC
• 3f63381: 8300913: ZGC: assert(to_addr != 0) failed: Should be forwarded
• da80e7a: 8300962: Parallel: Remove PSParallelCompact::_total_invocations
• 7725fe8: 8299953: Merge ContiguousSpaceDCTOC into DirtyCardToOopClosure
• a9b8acb: 8300652: Parallel: Refactor oop marking stack in Full GC
• 15a1488: 8297437: javadoc cannot link to old docs (with old style anchors)
• b0376a5: 8301069: Replace NULL with nullptr in share/libadt/
• 7328182: 8300958: Parallel: Remove unused MutableNUMASpace::capacity_in_words
• 30cb305: 8292170: Convert CodeRootSetTable to use ResourceHashtable
• ... and 59 more: https://git.openjdk.org/jdk/compare/5a4945c0d95423d0ab07762c915e9cb4d3c66abb...master

Your commit was automatically rebased without conflicts.

[openjdk]

@fisk Pushed as commit 973f741.

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