8370794: C2 SuperWord: Long/Integer.compareUnsigned return wrong value for EQ/NE in SLP

[rm-gh-8]

Backporting JDK-8370794: C2 SuperWord: Long/Integer.compareUnsigned return wrong value for EQ/NE in SLP.

This PR fixes a regression for vectorized unsigned integer/long equality checks.

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/c2/irTests/TestVectorConditionalMove.java
make test TEST=hotspot_compiler

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

---

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---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8370794 needs maintainer approval

Issue

• JDK-8370794: C2 SuperWord: Long/Integer.compareUnsigned return wrong value for EQ/NE in SLP (Bug - P2 - Approved)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk25u-dev.git pull/780/head:pull/780
$ git checkout pull/780

Update a local copy of the PR:
$ git checkout pull/780
$ git pull https://git.openjdk.org/jdk25u-dev.git pull/780/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 780

View PR using the GUI difftool:
$ git pr show -t 780

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk25u-dev/pull/780.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:

8370794: C2 SuperWord: Long/Integer.compareUnsigned return wrong value for EQ/NE in SLP

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[openjdk]

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

[mlbridge]

Webrevs

• 00: Full (3754ceb5)

[rm-gh-8]

/integrate

[openjdk]

Going to push as commit e0bf19c.
Since your change was applied there have been 7 commits pushed to the master branch:

• f8e9b5e: 8390469: LogTest_large_message_vm_Test::TestBody crashes in case of low disc space
• 56bd009: 8382338: Various serviceability agent tests fail on Linux x86_64 with LTO enabled
• b4b9425: 8387907: Shenandoah: Marking loop prefetch
• ... and 4 more: https://git.openjdk.org/jdk25u-dev/compare/5bf925d0f04717e16726a902de89421c9d78b1ca...master

Your commit was automatically rebased without conflicts.

[openjdk]

@rm-gh-8 Pushed as commit e0bf19c.

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