8386656: C2 AVX512: -XX:-UseCountTrailingZerosInstruction causes assert(UseCountTrailingZerosInstruction) failed: tzcnt instruction not supported

[ashu-mehra]

Backporting the fix for JDK-8386656 to jdk27.

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
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• Commit message must refer to an issue

Issue

• JDK-8386656: C2 AVX512: -XX:-UseCountTrailingZerosInstruction causes assert(UseCountTrailingZerosInstruction) failed: tzcnt instruction not supported (Bug - P3)

Reviewers

• Vladimir Kozlov (@vnkozlov - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk.git pull/31715/head:pull/31715
$ git checkout pull/31715

Update a local copy of the PR:
$ git checkout pull/31715
$ git pull https://git.openjdk.org/jdk.git pull/31715/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 31715

View PR using the GUI difftool:
$ git pr show -t 31715

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/31715.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back asmehra! A progress list of the required criteria for merging this PR into jdk27 will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

@ashu-mehra 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:

8386656: C2 AVX512: -XX:-UseCountTrailingZerosInstruction causes assert(UseCountTrailingZerosInstruction) failed: tzcnt instruction not supported

Reviewed-by: 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 no new commits pushed to the jdk27 branch. If another commit should be pushed before you perform the /integrate command, your PR will be automatically rebased. If you prefer to avoid any potential automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the jdk27 branch, type /integrate in a new comment.

[openjdk]

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

[openjdk]

@ashu-mehra The following label will be automatically applied to this pull request:

• hotspot-compiler

When this pull request is ready to be reviewed, an "RFR" email will be sent to the corresponding mailing list. If you would like to change these labels, use the /label pull request command.

[mlbridge]

Webrevs

• 00: Full (8e21ed1a)

[ashu-mehra]

fyi @eme64 @vnkozlov

[vnkozlov]

Good.

[ashu-mehra]

/integrate

[openjdk]

Going to push as commit 28720f1.
Since your change was applied there have been 3 commits pushed to the jdk27 branch:

• aaf11f8: 8385651: HotCodeSampler crashes with JFR enabled
• 5435c5c: 8387306: Replace InputStream#read(byte[]) with InputStream#readNBytes(int) in RtfConverter.isRtfFile()
• a6fb574: 8387259: Clarify extlang in Locale composition description

Your commit was automatically rebased without conflicts.

[openjdk]

@ashu-mehra Pushed as commit 28720f1.

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