8348562: ZGC: segmentation fault due to missing node type check in barrier elision analysis

[TheRealMDoerr]

Clean backport of JDK-8348562. The crashes can be reproduced in 21u by make run-test TEST="jdk/jfr/api/consumer/streaming/TestFilledChunks.java" JTREG="VM_OPTIONS=-XX:+UseZGC -XX:+ZGenerational" on linux PPC64le. The fix only adds a null check + bailout where the current implementation crashes with SIGSEGV. The test passes with this fix.

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Progress

• JDK-8348562 needs maintainer approval
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Issue

• JDK-8348562: ZGC: segmentation fault due to missing node type check in barrier elision analysis (Bug - P2)

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[openjdk]

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

[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.

[mlbridge]

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