8296912: C2: CreateExNode::Identity fails with assert(i < _max) failed: oob: i=1, _max=1

[TobiHartmann]

The fix for JDK-8284358 added code that aggressively removes dead subgraphs when detecting an unreachable Region by walking up the CFG and replacing all nodes by top (because they must be unreachable as well). In this case, we detect that 280 Region is unreachable from root and replace 276 Catch by top while walking up the CFG:

Code in CreateExNode::Identity does not expect 292 CatchProj to have a top input when processing 305 CreateEx. The fix is to simply add a in(0)->in(0)->is_Catch() check.

Thanks,
Tobias

---

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Issue

• JDK-8296912: C2: CreateExNode::Identity fails with assert(i < _max) failed: oob: i=1, _max=1

Reviewers

• Christian Hagedorn (@chhagedorn - Reviewer)
• Vladimir Kozlov (@vnkozlov - Reviewer)

Reviewing

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[openjdk]

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[mlbridge]

Webrevs

• 00: Full (a8cfe221)

[chhagedorn]

Looks good!

[openjdk]

@TobiHartmann 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:

8296912: C2: CreateExNode::Identity fails with assert(i < _max) failed: oob: i=1, _max=1

Reviewed-by: chagedorn, kvn

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 18 new commits pushed to the master branch:

• 8c26d02: 8295315: [REDO] 8276687 Remove support for JDK 1.4.1 PerfData shared memory files
• 8752bb4: 8296818: Enhance JMH tests java/security/Signatures.java
• b97fc93: 7132279: (ch) SeekableByteChannel operation may throw Non{Readable,Writable}ChannelException
• 39dda24: 8157173: [macosx] java/awt/Robot/ModifierRobotKey/ModifierRobotKeyTest.java fails
• 51f690d: 8297134: Add a @sealedGraph tag to InetAddress
• 3eb6d0e: 8291991: Adjust the "shared class paths mismatch" message if class path logging is enabled
• eac26f4: 8296709: WARNING: JNI call made without checking exceptions
• 4946737: 8297047: IGV: graphContent not set when opening a new tab
• 8b1ff9e: 8297132: BACKOUT JDK-8296889: Race condition when cancelling a request
• e72b0ac: 8296429: Remove os::supports_sse
• ... and 8 more: https://git.openjdk.org/jdk/compare/5e08b3f40e04254276fc2d37c523cb06b121861a...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.

[TobiHartmann]

Thanks for the quick review, Christian!

[vnkozlov]

Good.

[TobiHartmann]

Thanks for the review, Vladimir!

[TobiHartmann]

/integrate

[openjdk]

Going to push as commit 502fa3e.
Since your change was applied there have been 34 commits pushed to the master branch:

• 5795c76: 8296222: SwingEventMonitor - installListeners(Component , int ) - CELLEDITOR - bug
• b9d6e83: 8296906: VMError::controlled_crash crashes with wrong code and address
• cd9c688: 8276064: CheckCastPP with raw oop input floats below a safepoint
• d61720a: 8218885: Restore pop_frame and force_early_return functionality for Graal
• dd9aa72: 8296083: javax/swing/JTree/6263446/bug6263446.java fails intermittently on a VM
• cc44419: 8295407: C2 crash: Error: ShouldNotReachHere() in multiple vector tests with -XX:-MonomorphicArrayCheck -XX:-UncommonNullCast
• e2269fd: 8296968: Update langtools tests to use @enablePreview
• 2159170: 8296453: Simplify resource_area uses in ClassPathDirEntry::open_stream
• 95c390e: 8296956: [JVMCI] HotSpotResolvedJavaFieldImpl.getIndex returns wrong value
• 68d3ed5: 8296442: EncryptedPrivateKeyInfo can be created with an uninitialized AlgorithmParameters
• ... and 24 more: https://git.openjdk.org/jdk/compare/5e08b3f40e04254276fc2d37c523cb06b121861a...master

Your commit was automatically rebased without conflicts.

[openjdk]

@TobiHartmann Pushed as commit 502fa3e.

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