8306582: Remove MetaspaceShared::exit_after_static_dump()

[matias9927]

Currently we exit the VM after static dumping with MetaspaceShared::exit_after_static_dump().

 // We have finished dumping the static archive. At this point, there may be pending VM
 // operations. We have changed some global states (such as vmClasses::_klasses) that
 // may cause these VM operations to fail. For safety, forget these operations and
 // exit the VM directly.
 void MetaspaceShared::exit_after_static_dump() {
   os::_exit(0);
 } 

As the comment suggests, the VM state is altered when preparing and performing the static dump, so this change aims to prevent these state changes so the VM can exit normally after the static dump completes. There are three major aspects to this change:

1. Since the resolved references array in the Constant Pool is altered when preparing for a static dump, a "scratch copy" is created and archived instead
2. Symbols are sorted by address and have their hash recalculated. Similarly to point 1, the copies of the symbols that are to be archived have their hashes updated as opposed to the originals.
3. The handling of -Xshare:dump during argument parsing such that the VM can continue and exit normally with an exit code of 0.

Verified with tier 1-9 tests.

---

Progress

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Issue

• JDK-8306582: Remove MetaspaceShared::exit_after_static_dump() (Enhancement - P4)

Reviewers

• Ioi Lam (@iklam - Reviewer) ⚠️ Review applies to dc1915dc
• Alan Bateman (@AlanBateman - Reviewer) ⚠️ Review applies to 64d8c638
• Calvin Cheung (@calvinccheung - Reviewer)

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[bridgekeeper]

👋 Welcome back matsaave! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

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[mlbridge]

Webrevs

• 04: Full - Incremental (f4f9091a)
• 03: Full - Incremental (64d8c638)
• 02: Full - Incremental (dc1915dc)
• 01: Full (900fa187)
• 00: Full (07c64fca)

[dholmes-ora]

Hi Matias,

I'm not keen on having to teach the launcher about -Xshare:dump and that it is a terminal operation. But after looking into it I have to admit it is a cleaner and more consistent termination strategy. That said you need to be aware that this will now do a clean shutdown of the VM after the dump, so shutdown hooks will now run.

Lets see what core-libs folk think too.

Thanks.

[openjdk]

⚠️ @matias9927 This pull request contains merges that bring in commits not present in the target repository. Since this is not a "merge style" pull request, these changes will be squashed when this pull request in integrated. If this is your intention, then please ignore this message. If you want to preserve the commit structure, you must change the title of this pull request to Merge <project>:<branch> where <project> is the name of another project in the OpenJDK organization (for example Merge jdk:master).

[matias9927]

I messed up a merge and pushed the incorrect contents to this PR. It will be temporarily reverted to a draft and force pushed to undo my mistake.

The existing comments should be addressed in the most recent commits.

[iklam]

Looks good overall. Some suggestions for code refactoring.

[iklam]

Looks good. Just a couple of nits.

[openjdk]

@matias9927 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:

8306582: Remove MetaspaceShared::exit_after_static_dump()

Reviewed-by: iklam, alanb, ccheung

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 2 new commits pushed to the master branch:

• bf70777: 8312181: CDS dynamic dump crashes when verifying unlinked class from static archive
• 7ba8c69: 8312596: Null pointer access in Compile::TracePhase::~TracePhase after JDK-8311976

Please see this link for an up-to-date comparison between the source branch of this pull request and the master branch.
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.

[AlanBateman]

Updated launcher change looks fine.

[calvinccheung]

Looks good overall. I have one question.

[matias9927]

Thank you for the reviews @iklam, @calvinccheung, @dholmes-ora, and @AlanBateman!
/integrate

[openjdk]

Going to push as commit cff25dd.
Since your change was applied there have been 18 commits pushed to the master branch:

• 4ba81f6: 8313368: (fc) FileChannel.size returns 0 on block special files
• c1a3f14: 8312078: [PPC] JcmdScale.java Failing on AIX
• 6446792: 8312617: SIGSEGV in ConnectionGraph::verify_ram_nodes
• b093880: 8313322: RISC-V: implement MD5 intrinsic
• 19e2c8c: 8313593: Generational ZGC: NMT assert when the heap fails to expand
• 46fbedb: 8313402: C1: Incorrect LoadIndexed value numbering
• 6faf05c: 8311989: Test java/lang/Thread/virtual/Reflection.java timed out
• 5d1b911: 8310311: Serial: move Generation::contribute_scratch to DefNewGeneration
• 9454b2b: 8312591: GCC 6 build failure after JDK-8280982
• 6a853bb: 8311821: Simplify ParallelGCThreadsConstraintFunc after CMS removal
• ... and 8 more: https://git.openjdk.org/jdk/compare/ec2f38fd389dc51dc4d8925e037a8bf2e64a3722...master

Your commit was automatically rebased without conflicts.

[openjdk]

@matias9927 Pushed as commit cff25dd.

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