8382315: RISC-V: TestMultiplyReductionByte.java fails with guarantee(is_uimm5(imm)) failed: uimm is invalid

[DingliZhang]

Hi, please review.

The vector slide down instruction vslidedown_vi can only encode a 5-bit zero-extended offset.
But that is not handled properly in C2_MacroAssembler::reduce_mul_integral_v which uses this instruction.
The contraint won't be satisfied when running compiler.vectorapi.TestMultiplyReductionByte::testMulReduce512
with a much larger MaxVectorSize (>= 64 bytes).
This fixes the issue by introducing a new macro-assembler routine slidedown_v which would do the check
and delegates work to either vslidedown_vi or vslidedown_vx accordingly.

Testing:
Same test using fastdebug build on linux-riscv64 qemu (MaxVectorSize = 64).
hs:tier1 - hs:tier3 using fastdebug build on linux-riscv64 qemu (MaxVectorSize = 16).

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Issue

• JDK-8382315: RISC-V: TestMultiplyReductionByte.java fails with guarantee(is_uimm5(imm)) failed: uimm is invalid (Bug - P4)

Reviewers

• Fei Yang (@RealFYang - Reviewer)
• Gui Cao (@zifeihan - Author)

Reviewing

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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.

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:

8382315: RISC-V: TestMultiplyReductionByte.java fails with guarantee(is_uimm5(imm)) failed: uimm is invalid

Reviewed-by: fyang, gcao

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 38 new commits pushed to the master branch:

• 35f623b: 8382090: Remove .rej and .orig from .gitignore
• 8d79d47: 8382391: Cleanup unnecessary storestore() in stringStream::as_string
• 35b0de3: 8382043: Add missing @OverRide annotations in "javax.print.attribute" package
• ... and 35 more: https://git.openjdk.org/jdk/compare/01bfd427a322c6f92643c7920bbd1b1b35141a69...master

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 master branch, type /integrate in a new comment.

[openjdk]

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

• hotspot-compiler

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[mlbridge]

Webrevs

• 01: Full - Incremental (329a1bc7)
• 00: Full (7542113d)

[RealFYang]

Looks reasonable. Thanks.

[zifeihan]

LGTM.

[openjdk]

The total number of required reviews for this PR has been set to 2 based on the presence of this label: hotspot-compiler. This can be overridden with the /reviewers command.

[RealFYang]

Still good.

[DingliZhang]

Thanks all for the review!
/integrate

[openjdk]

@DingliZhang This pull request has not yet been marked as ready for integration.

[DingliZhang]

Thanks all for the review!
/integrate

[openjdk]

Going to push as commit da0a7b1.
Since your change was applied there have been 39 commits pushed to the master branch:

• 444e6f6: 8382312: Cleanup instanceKlass dead code
• 35f623b: 8382090: Remove .rej and .orig from .gitignore
• 8d79d47: 8382391: Cleanup unnecessary storestore() in stringStream::as_string
• ... and 36 more: https://git.openjdk.org/jdk/compare/01bfd427a322c6f92643c7920bbd1b1b35141a69...master

Your commit was automatically rebased without conflicts.

[openjdk]

@DingliZhang Pushed as commit da0a7b1.

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