8360405: [PPC64] some environments don't support mfdscr instruction

[TheRealMDoerr]

Clean backport of JDK-8360405.

---

Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issue

• JDK-8360405: [PPC64] some environments don't support mfdscr instruction (Bug - P3)

Reviewers

• Hao Sun (@shqking - Committer)
• Richard Reingruber (@reinrich - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk.git pull/25972/head:pull/25972
$ git checkout pull/25972

Update a local copy of the PR:
$ git checkout pull/25972
$ git pull https://git.openjdk.org/jdk.git pull/25972/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 25972

View PR using the GUI difftool:
$ git pr show -t 25972

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/25972.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back mdoerr! A progress list of the required criteria for merging this PR into jdk25 will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

@TheRealMDoerr 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:

8360405: [PPC64] some environments don't support mfdscr instruction

Reviewed-by: haosun, rrich

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 2 new commits pushed to the jdk25 branch:

• a84946d: 8359268: 3 JNI exception pending defect groups in 2 files
• fdb3e37: 8359788: Internal Error: assert(get_instanceKlass()->is_loaded()) failed: must be at least loaded

Please see this link for an up-to-date comparison between the source branch of this pull request and the jdk25 branch.
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 jdk25 branch, type /integrate in a new comment.

[openjdk]

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

[openjdk]

@TheRealMDoerr The following label will be automatically applied to this pull request:

• hotspot

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[mlbridge]

Webrevs

• 00: Full (16c740cc)

[shqking]

Thanks for your fix.

As I tested with jdk25 branch in my environment(QEMU), it failed to run java -version before this PR, and it can pass with this PR.

[TheRealMDoerr]

Thanks for the reviews and for verifying!
/integrate

[openjdk]

Going to push as commit 274a2dd.
Since your change was applied there have been 2 commits pushed to the jdk25 branch:

• a84946d: 8359268: 3 JNI exception pending defect groups in 2 files
• fdb3e37: 8359788: Internal Error: assert(get_instanceKlass()->is_loaded()) failed: must be at least loaded

Your commit was automatically rebased without conflicts.

[openjdk]

@TheRealMDoerr Pushed as commit 274a2dd.

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