8361117: SIGSEGV in LShiftLNode::Ideal due to unexpected dead node

[TheRealMDoerr]

This is a new fix for JDK-8361117 for OpenJDK. I can't see the corresponding fix because it's not public.

This fix is taken from openjdk/jdk@05a0a71.
The problem is described in https://github.com/openjdk/jdk/blob/674cc3eeca77f1f2a6d937b1df5c5cd8a13c2d31/test/hotspot/jtreg/compiler/arraycopy/TestACSameSrcDst.java#L87 but that regression test didn't reproduce the issue in jdk17u.

I've taken the reproducer from the issue and put it into a new regression test. The VM crashes without the fix and the test passes with the fix.

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8361117 needs maintainer approval

Issue

• JDK-8361117: SIGSEGV in LShiftLNode::Ideal due to unexpected dead node (Bug - P2 - Approved)

Reviewers

• Roland Westrelin (@rwestrel - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk17u-dev.git pull/4204/head:pull/4204
$ git checkout pull/4204

Update a local copy of the PR:
$ git checkout pull/4204
$ git pull https://git.openjdk.org/jdk17u-dev.git pull/4204/head

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Checkout this PR locally:
$ git pr checkout 4204

View PR using the GUI difftool:
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Download this PR as a diff file:
https://git.openjdk.org/jdk17u-dev/pull/4204.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back mdoerr! 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]

@TheRealMDoerr 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:

8361117: SIGSEGV in LShiftLNode::Ideal due to unexpected dead node

Reviewed-by: roland

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 6 new commits pushed to the master branch:

• 5014504: 8283784: java_lang_String::as_platform_dependent_str stores to oop in native state
• b6eb8ce: 8337681: PNGImageWriter uses much more memory than necessary
• e904358: 8282484: G1: Predicted old time in log always zero
• ... and 3 more: https://git.openjdk.org/jdk17u-dev/compare/e853a440562f067b851a449242d808e271817001...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.

[openjdk]

This backport pull request has now been updated with the original issue, but not the original commit. If you have the original commit hash, please update the pull request title with Backport <hash>.

[mlbridge]

Webrevs

• 01: Full - Incremental (3c8ec182)
• 00: Full (40c63e86)

[TheRealMDoerr]

@rwestrel: Do you want to review?

[rwestrel]

Otherwise, looks good to me.

[rwestrel]

Can you rename the test case? The usual guideline is to not name test cases based on the bug id but rather have a short descriptive name.

[TheRealMDoerr]

Done. Please take a look.

[rwestrel]

Thanks for making the change. Looks good to me.

[openjdk]

⚠️ @TheRealMDoerr This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[TheRealMDoerr]

Thanks for the review!

[TheRealMDoerr]

/integrate

[openjdk]

Going to push as commit 58dab5e.
Since your change was applied there have been 6 commits pushed to the master branch:

• 5014504: 8283784: java_lang_String::as_platform_dependent_str stores to oop in native state
• b6eb8ce: 8337681: PNGImageWriter uses much more memory than necessary
• e904358: 8282484: G1: Predicted old time in log always zero
• ... and 3 more: https://git.openjdk.org/jdk17u-dev/compare/e853a440562f067b851a449242d808e271817001...master

Your commit was automatically rebased without conflicts.

[openjdk]

@TheRealMDoerr Pushed as commit 58dab5e.

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