8365200: RISC-V: compiler/loopopts/superword/TestGeneralizedReductions.java fails with Zvbb and vlen=128

[DingliZhang]

Hi all,
Please take a look and review this PR, thanks!

JDK-8352529 enables this IR verification test for riscv. This test pass with zvbb when vlen=256, but fail when vlen=128.

The reason for the error is the same as JDK-8357694. 2-element reductions for INT/LONG are not profitable, so the compiler won't generate the corresponding reductions IR.

This issue was not addressed together with JDK-8357694 because the testMapReductionOnGlobalAccumulator case where the error is reported has a different applyif method from other cases: zvbb needs to be enabled.

Test (fastdebug)

• Run compiler/loopopts/superword/TestGeneralizedReductions.java on qemu-system w/ and w/o zvbb when vlen=256
• Run compiler/loopopts/superword/TestGeneralizedReductions.java on qemu-system w/ and w/o zvbb when vlen=128

---

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Issue

• JDK-8365200: RISC-V: compiler/loopopts/superword/TestGeneralizedReductions.java fails with Zvbb and vlen=128 (Bug - P4)

Reviewers

• Fei Yang (@RealFYang - Reviewer)
• Feilong Jiang (@feilongjiang - Committer) Review applies to cdae1d05

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[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]

@DingliZhang This change now passes all automated pre-integration checks.

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After integration, the commit message for the final commit will be:

8365200: RISC-V: compiler/loopopts/superword/TestGeneralizedReductions.java fails with Zvbb and vlen=128

Reviewed-by: fyang, fjiang

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 17 new commits pushed to the master branch:

• 9593730: 8362376: Use @stable annotation in Java FDLIBM implementation
• 8cd7975: 8364761: (aio) AsynchronousChannelGroup.execute doesn't check null command
• 958383d: 8364501: Compiler shutdown crashes on access to deleted CompileTask
• ... and 14 more: https://git.openjdk.org/jdk/compare/022e29a77533aacabd56820d00ecffa9646a8362...master

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

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[mlbridge]

Webrevs

• 01: Full - Incremental (703205d3)
• 00: Full (cdae1d05)

[RealFYang]

Thanks!

[feilongjiang]

Thanks for catching this!

[DingliZhang]

Thanks all for the review!
/integrate

[openjdk]

@DingliZhang
Your change (at version 703205d) is now ready to be sponsored by a Committer.

[feilongjiang]

/sponsor

[openjdk]

Going to push as commit 6927fc3904eb239bd43ab7c581d479c00a6a4af2.
Since your change was applied there have been 17 commits pushed to the master branch:

• 9593730: 8362376: Use @stable annotation in Java FDLIBM implementation
• 8cd7975: 8364761: (aio) AsynchronousChannelGroup.execute doesn't check null command
• 958383d: 8364501: Compiler shutdown crashes on access to deleted CompileTask
• ... and 14 more: https://git.openjdk.org/jdk/compare/022e29a77533aacabd56820d00ecffa9646a8362...master

Your commit was automatically rebased without conflicts.

[openjdk]

@feilongjiang @DingliZhang Pushed as commit 6927fc3.

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