8309254: Implement fast-path for ASCII-compatible CharsetEncoders on RISC-V

[DingliZhang]

I would like to backport JDK-8309254.
The backport is not clean because 17u has no JDK-8302908, which use v0 as mask register.
The test test/hotspot/jtreg/compiler/intrinsics/string/TestEncodeIntrinsics.java passed and command log with "-XX:+PrintOptoAssembly" output is similar to the mainline:

...
240     Encode ISO array R12, R11, R13 -> R10 # KILL R12, R11, R13, R28, V1-V3
...
0118    Encode ASCII array R12, R11, R13 -> R10 # KILL R12, R11, R13, R25, V1-V3
...

---

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-8309254: Implement fast-path for ASCII-compatible CharsetEncoders on RISC-V (Enhancement - P4)

Reviewers

• Fei Yang (@RealFYang - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk17u-dev.git pull/1567/head:pull/1567
$ git checkout pull/1567

Update a local copy of the PR:
$ git checkout pull/1567
$ git pull https://git.openjdk.org/jdk17u-dev.git pull/1567/head

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Checkout this PR locally:
$ git pr checkout 1567

View PR using the GUI difftool:
$ git pr show -t 1567

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk17u-dev/pull/1567.diff

Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back dzhang! 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 backport pull request has now been updated with issue from the original commit.

[mlbridge]

Webrevs

• 02: Full - Incremental (539e39fe)
• 01: Full - Incremental (bd1c4506)
• 00: Full (2afc6793)

[RealFYang]

Looks good. (Not a JDK Updates Reviewer)
I think this is on par with https://bugs.openjdk.org/browse/JDK-8274243 which has been backported to jdk17u.

[DingliZhang]

Tier1-3 with UseRVV looks good.
Could we have a Reviewer?

[bridgekeeper]

@DingliZhang This pull request has been inactive for more than 4 weeks and will be automatically closed if another 4 weeks passes without any activity. To avoid this, simply add a new comment to the pull request. Feel free to ask for assistance if you need help with progressing this pull request towards integration!

[openjdk]

@DingliZhang 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:

8309254: Implement fast-path for ASCII-compatible CharsetEncoders on RISC-V

Reviewed-by: fyang

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 master branch:

• 4dca60e: 8293166: jdk/jfr/jvm/TestDumpOnCrash.java fails on Linux ppc64le and Linux aarch64
• 41cadb7: 8313765: Invalid CEN header (invalid zip64 extra data field size)

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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.

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[DingliZhang]

@RealFYang Thanks for the review!
/integrate

[openjdk]

@DingliZhang
Your change (at version 539e39f) is now ready to be sponsored by a Committer.

[RealFYang]

/sponsor

[openjdk]

Going to push as commit 0fa04fe.
Since your change was applied there have been 2 commits pushed to the master branch:

• 4dca60e: 8293166: jdk/jfr/jvm/TestDumpOnCrash.java fails on Linux ppc64le and Linux aarch64
• 41cadb7: 8313765: Invalid CEN header (invalid zip64 extra data field size)

Your commit was automatically rebased without conflicts.

[openjdk]

@RealFYang @DingliZhang Pushed as commit 0fa04fe.

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