8307533: Use atomic bitset functions for metadata flags

[coleenp]

Replace the bit set copies from metadata to use the Atomic functions.
Tested with tier1-4.

---

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Issue

• JDK-8307533: Use atomic bitset functions for metadata flags

Reviewers

• Calvin Cheung (@calvinccheung - Reviewer) ⚠️ Review applies to 7009b524
• Kim Barrett (@kimbarrett - Reviewer)

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• 02: Full - Incremental (9c53bfe6)
• 01: Full - Incremental (91de5aa4)
• 00: Full (7009b524)

[calvinccheung]

LGTM.
Looks like we can do similar change to the set_defined_by_cds_in_class_path() function in packageEntry.hpp. I can file a bug to take care of that.

[openjdk]

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

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8307533: Use atomic bitset functions for metadata flags

Reviewed-by: ccheung, kbarrett

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[kimbarrett]

The failures to build when the extra variables are removed is because of integral arithmetic promotion by the ~bits expression. That causes the resulting value of that expression to be of a different type from the atomic value.

[kimbarrett]

The Atomic bitops aren't intended to support other sizes; only the same sizes as Atomic::add and friends. That narrower
types are currently supported by the default implementation is an accident. Platform specializations might not have such
support, since the underlying platform might not have it.

If support for narrower types is a (not previously known to me) requirement, some non-trivial changes may be needed.
Among other things, I think the current very simple platform specialization mechanism won't be sufficient.

[coleenp]

@kimbarrett thank you for adding support for u1 types. I merged with the latest changes.

[kimbarrett]

Looks good.

[coleenp]

Thanks Calvin and Kim
/integrate

[openjdk]

Going to push as commit 488330d.
Since your change was applied there have been 24 commits pushed to the master branch:

• 60ab135: 8308097: Generational ZGC: Update constructor syntax
• 599fa77: 8308092: Replace NULL with nullptr in gc/x
• 682359c: 8299075: TestStringDeduplicationInterned.java fails because extra deduplication
• 9d5bab1: 8300081: Replace NULL with nullptr in share/asm/
• 41ee125: 8278411: Implement UseHeavyMonitors consistently, s390 port
• 316bc79: 8308188: ProblemList java/util/concurrent/locks/Lock/OOMEInAQS.java with ZGC on all platforms
• 8686a36: 8307315: Missing ResourceMark in CDS and JVMTI code
• 23cbb2d: 8306860: Avoid unnecessary allocation in List.map() when list is empty
• be54b54: 8307369: Add execution of all svc tests in CI
• 19c8c30: 8305634: Renaming predicates, simple cleanups, and adding summary about current predicates
• ... and 14 more: https://git.openjdk.org/jdk/compare/97b2ca3de76046c6f52d3649d8787feea7b9ac83...master

Your commit was automatically rebased without conflicts.

[openjdk]

@coleenp Pushed as commit 488330d.

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