8388439: [s390x] LoadNKlass rule doesn't kill CC

[offamitkumar]

Hi all,

This pull request contains a backport of commit 857df837 from the openjdk/jdk repository.

effect(KILL cr); for the rule loadNKlassCompactHeaders is wrong. it uses two instruction lg + srlg both of which are not killing CC according to Z operations book.

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Progress

• Change must not contain extraneous whitespace
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Issue

• JDK-8388439: [s390x] LoadNKlass rule doesn't kill CC (Enhancement - P4)

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[bridgekeeper]

👋 Welcome back amitkumar! 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 change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

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

[openjdk]

⚠️ @offamitkumar 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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• 00: Full (9f859837)