8296412: Special case infinite loops with unmerged backedges in IdealLoopTree::check_safepts

[GoeLin]

I backport this for parity with 17.0.8-oracle.

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Progress

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Issue

• JDK-8296412: Special case infinite loops with unmerged backedges in IdealLoopTree::check_safepts

Reviewing

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$ git fetch https://git.openjdk.org/jdk17u-dev.git pull/1287/head:pull/1287
$ git checkout pull/1287

Update a local copy of the PR:
$ git checkout pull/1287
$ git pull https://git.openjdk.org/jdk17u-dev.git pull/1287/head

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$ git pr checkout 1287

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https://git.openjdk.org/jdk17u-dev/pull/1287.diff

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[bridgekeeper]

👋 Welcome back goetz! 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]

This backport pull request has now been updated with issue from the original commit.

[openjdk]

@GoeLin 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:

8296412: Special case infinite loops with unmerged backedges in IdealLoopTree::check_safepts

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 1 new commit pushed to the master branch:

• 9d6f1d7: 8201516: DebugNonSafepoints generates incorrect information

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[mlbridge]

Webrevs

• 00: Full (fa4651a3)

[GoeLin]

Pre-submit failure: Run Visual Studio Installer
Error: Process completed with exit code 1.
Unrelated.

[GoeLin]

/integrate

[openjdk]

Going to push as commit ee63f83.
Since your change was applied there have been 5 commits pushed to the master branch:

• 1dee04a: 8278146: G1: Rework VM_G1Concurrent VMOp to clearly identify it as pause
• a000b2d: 8238274: (sctp) JDK-7118373 is not fixed for SctpChannel
• f969f81: 8301998: Update HarfBuzz to 7.0.1
• ebde2fb: 8306543: GHA: MSVC installation is failing
• 9d6f1d7: 8201516: DebugNonSafepoints generates incorrect information

Your commit was automatically rebased without conflicts.

[openjdk]

@GoeLin Pushed as commit ee63f83.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.