8354242: VectorAPI: combine vector not operation with compare

[rm-gh-8]

Backporting JDK-8354242: VectorAPI: combine vector not operation with compare.

This PR implements a C2 JIT optimization that changes a negated Vector API mask compare into a single compare with the opposite predicate.

This is a prerequisite for JDK-8370481 (#728) and JDK-8370794, which are for parity with Oracle JDK.

Ran related tests on linux-x64, linux-aarch64, macos-aarch64 and windows-x64:

make test TEST=test/hotspot/jtreg/compiler/vectorapi
make test TEST=test/hotspot/jtreg/compiler/c2/irTests

Results:

windows-x64-specific-test.log
windows-x64-specific-2-test.log
macos-aarch64-specific-test.log
macos-aarch64-specific-2-test.log
linux-x64-specific-test.log
linux-x64-specific-2-test.log
linux-aarch64-specific-test.log
linux-aarch64-specific-2-test.log

Ran the following benchmark on linux-x64, linux-aarch64, macos-aarch64 and windows-x64:

./build/*/images/jdk/bin/java -jar build/*/images/test/micro/benchmarks.jar org.openjdk.bench.jdk.incubator.vector.MaskCompareNotBenchmark

windows-x64-benchmark-test-before-change.log
windows-x64-benchmark-test.log
macos-aarch64-benchmark-test-before-change.log
macos-aarch64-benchmark-test.log
linux-x64-benchmark-test-before-change.log
linux-x64-benchmark-test.log
linux-aarch64-benchmark-test-before-change.log
linux-aarch64-benchmark-test.log

Across all four platforms (linux-aarch64, linux-x64, macos-aarch64, windows-x64), the change did not produce performance regressions.

---

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---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8354242 needs maintainer approval

Issue

• JDK-8354242: VectorAPI: combine vector not operation with compare (Enhancement - P4 - Approved)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk25u-dev.git pull/725/head:pull/725
$ git checkout pull/725

Update a local copy of the PR:
$ git checkout pull/725
$ git pull https://git.openjdk.org/jdk25u-dev.git pull/725/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 725

View PR using the GUI difftool:
$ git pr show -t 725

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk25u-dev/pull/725.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back rmesde! 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]

@rm-gh-8 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:

8354242: VectorAPI: combine vector not operation with compare

You can use pull request commands such as /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 3 new commits pushed to the master branch:

• c4deee6: 8387391: hotspot_gc_shenandoah should include gtests
• f4b65e0: 8373820: C2: Robust Node::uncast_helper infinite loop check
• 46fce67: 8347007: --strip-debug removes parameter names included with -parameters

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

[openjdk]

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

[openjdk]

⚠️ @rm-gh-8 This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[rm-gh-8]

/approval request for backport of JDK-8354242: VectorAPI: combine vector not operation with compare.

This PR implements a C2 JIT optimization that changes a negated Vector API mask compare into a single compare with the opposite predicate.

This is a prerequisite for JDK-8370481 and JDK-8370794, which are for parity with Oracle JDK.

Low risk — it is a narrow C2 JIT optimization that includes a new test to validate.

[openjdk]

@rm-gh-8
8354242: The approval request has been created successfully.

[mlbridge]

Webrevs

• 00: Full (c55e2d8f)

[rm-gh-8]

/integrate

[openjdk]

Going to push as commit ecabaf0.
Since your change was applied there have been 7 commits pushed to the master branch:

• 5d2c24c: 8367008: Algorithm identifiers for HmacSHA* should always have NULL as params
• f3f0497: 8383196: Shenandoah: Interpreter barriers clobber interpreter registers
• 7f24d97: 8382150: Shenandoah: Clean up nmethod entry barrier support
• ... and 4 more: https://git.openjdk.org/jdk25u-dev/compare/29d0b2b336e0a936436a5799d4bbdf4123155c09...master

Your commit was automatically rebased without conflicts.

[openjdk]

@rm-gh-8 Pushed as commit ecabaf0.

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