8328702: C2: Crash during parsing because sub type check is not folded

[shipilev]

Fixes another C2 bug, regression in JDK 21.

Additional testing:

• New regression test fails without the fix, passes with it
• Linux x86_64 server fastdebug, all tests pass
• Linux x86_64 server fastdebug, Fuzzer tests
• Linux x86_64 server fastdebug, Maven CTW tests

---

Progress

• Change must not contain extraneous whitespace
• JDK-8328702 needs maintainer approval
• Commit message must refer to an issue

Issue

• JDK-8328702: C2: Crash during parsing because sub type check is not folded (Bug - P2 - Approved)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk21u-dev.git pull/450/head:pull/450
$ git checkout pull/450

Update a local copy of the PR:
$ git checkout pull/450
$ git pull https://git.openjdk.org/jdk21u-dev.git pull/450/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 450

View PR using the GUI difftool:
$ git pr show -t 450

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk21u-dev/pull/450.diff

Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back shade! 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]

@shipilev 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:

8328702: C2: Crash during parsing because sub type check is not folded

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 47 new commits pushed to the master branch:

• 6f60957: 8328037: Test java/util/Formatter/Padding.java has unnecessary high heap requirement after JDK-8326718
• c254aff: 8321718: ProcessTools.executeProcess calls waitFor before logging
• 38a2173: 8318585: Rename CodeCache::UnloadingScope to UnlinkingScope
• e0d2248: 8311881: jdk/javax/swing/ProgressMonitor/ProgressTest.java does not show the ProgressMonitorInputStream all the time
• 8173c64: 8329570: G1: Excessive is_obj_dead_cond calls in verification
• e95e6fe: 8305645: System Tray icons get corrupted when Windows primary monitor changes
• 88abc6a: 8328604: remove on_aix() function
• fd50739: 8315652: RISC-V: Features string uses wrong separator for jtreg
• d5f44dc: 8319650: Improve heap dump performance with class metadata caching
• b9ca253: 8325203: System.exit(0) kills the launched 3rd party application
• ... and 37 more: https://git.openjdk.org/jdk21u-dev/compare/2800d8bc708f7ccdf32ef64c52f99f40b1459698...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 issue from the original commit.

[openjdk]

⚠️ @shipilev 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.

[mlbridge]

Webrevs

• 00: Full (2f80e7f3)

[shipilev]

/approval request Fixes another C2 bug, regression in JDK 21. Usual risk for C2 changes, but the fix looks simple enough. Passes all tests, including the aggressive compiler testing. New regression test fails without the fix, passes with it.

[openjdk]

@shipilev
8328702: The approval request has been created successfully.

[shipilev]

/integrate

[openjdk]

Going to push as commit 249d896.
Since your change was applied there have been 47 commits pushed to the master branch:

• 6f60957: 8328037: Test java/util/Formatter/Padding.java has unnecessary high heap requirement after JDK-8326718
• c254aff: 8321718: ProcessTools.executeProcess calls waitFor before logging
• 38a2173: 8318585: Rename CodeCache::UnloadingScope to UnlinkingScope
• e0d2248: 8311881: jdk/javax/swing/ProgressMonitor/ProgressTest.java does not show the ProgressMonitorInputStream all the time
• 8173c64: 8329570: G1: Excessive is_obj_dead_cond calls in verification
• e95e6fe: 8305645: System Tray icons get corrupted when Windows primary monitor changes
• 88abc6a: 8328604: remove on_aix() function
• fd50739: 8315652: RISC-V: Features string uses wrong separator for jtreg
• d5f44dc: 8319650: Improve heap dump performance with class metadata caching
• b9ca253: 8325203: System.exit(0) kills the launched 3rd party application
• ... and 37 more: https://git.openjdk.org/jdk21u-dev/compare/2800d8bc708f7ccdf32ef64c52f99f40b1459698...master

Your commit was automatically rebased without conflicts.

[openjdk]

@shipilev Pushed as commit 249d896.

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