8329749: Obsolete the unused UseNeon flag

[TobiHartmann]

After JDK-8328264, the UseNeon flag is only used by JVMCI code and @dougxc confirmed that it can be removed.

Thanks,
Tobias

---

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
• Change requires CSR request JDK-8329753 to be approved

Issues

• JDK-8329749: Obsolete the unused UseNeon flag (Enhancement - P4)
• JDK-8329753: Obsolete UseNeon (CSR)

Reviewers

• Christian Hagedorn (@chhagedorn - Reviewer) ⚠️ Review applies to 5d8119ab
• Vladimir Kozlov (@vnkozlov - Reviewer) ⚠️ Review applies to 5d8119ab
• Andrew Haley (@theRealAph - Reviewer)

Reviewing

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[bridgekeeper]

👋 Welcome back thartmann! 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]

@TobiHartmann 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:

8329749: Obsolete the unused UseNeon flag

Reviewed-by: chagedorn, kvn, aph

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 40 new commits pushed to the master branch:

• 6f087cb: 8328698: oopDesc::klass_raw() decodes without a null check
• d1aad71: 8321204: C2: assert(false) failed: node should be in igvn hash table
• 51b0abc: 8329340: Remove unused libawt code
• 3a3b77d: 8329641: RISC-V: Enable some tests related to SHA-2 instrinsic
• d771ec6: 8329733: Update the documentation in java.net.SocketOptions to direct to java.net.StandardSocketOptions
• 49d8e63: 8329083: RISC-V: Update profiles supported on riscv
• 3d50eaa: 8329784: Run MaxMetaspaceSizeTest.java with -Xshare:off
• 862e615: 8198237: [macos] Test java/awt/Frame/ExceptionOnSetExtendedStateTest/ExceptionOnSetExtendedStateTest.java fails
• 040c935: 8328183: Minor mistakes in docs of PrintStream.append()
• 4a11db8: 8329662: Add a test to verify the behaviour of the default HEAD() method on HttpRequest.Builder
• ... and 30 more: https://git.openjdk.org/jdk/compare/f26e4308992d989d71e7fbfaa3feb95f0ea17c06...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]

@TobiHartmann The following labels will be automatically applied to this pull request:

• graal
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[mlbridge]

Webrevs

• 02: Full - Incremental (370a7b9a)
• 01: Full - Incremental (5d8119ab)
• 00: Full (9da49928)

[TobiHartmann]

@chhagedorn reminded me that this is a product flag, so we need to obsolete it which requires a CSR. I'll update the PR shortly.

[chhagedorn]

Looks good!

[TobiHartmann]

Thanks, Christian!

[vnkozlov]

Good

[altrisi]

Should the UseNeon enum constant this code referenced be removed too?

jdk/src/jdk.internal.vm.ci/share/classes/jdk/vm/ci/aarch64/AArch64.java

Lines 191 to 193 in 5d8119a

	public enum Flag {
	UseCRC32,
	UseNeon,

[TobiHartmann]

Should the UseNeon enum constant this code referenced be removed too?

Good catch. Removed as well.

[TobiHartmann]

Thanks for the reviews, @vnkozlov, @altrisi!

[TobiHartmann]

Thanks for the review, Andrew.

[TobiHartmann]

/integrate

[openjdk]

Going to push as commit 8648890.
Since your change was applied there have been 42 commits pushed to the master branch:

• fc18201: 8327111: Replace remaining usage of create_bool_from_template_assertion_predicate() which requires additional OpaqueLoop*Nodes transformation strategies
• 7c66465: 8325088: Overloads that differ in type parameters may be lost
• 6f087cb: 8328698: oopDesc::klass_raw() decodes without a null check
• d1aad71: 8321204: C2: assert(false) failed: node should be in igvn hash table
• 51b0abc: 8329340: Remove unused libawt code
• 3a3b77d: 8329641: RISC-V: Enable some tests related to SHA-2 instrinsic
• d771ec6: 8329733: Update the documentation in java.net.SocketOptions to direct to java.net.StandardSocketOptions
• 49d8e63: 8329083: RISC-V: Update profiles supported on riscv
• 3d50eaa: 8329784: Run MaxMetaspaceSizeTest.java with -Xshare:off
• 862e615: 8198237: [macos] Test java/awt/Frame/ExceptionOnSetExtendedStateTest/ExceptionOnSetExtendedStateTest.java fails
• ... and 32 more: https://git.openjdk.org/jdk/compare/f26e4308992d989d71e7fbfaa3feb95f0ea17c06...master

Your commit was automatically rebased without conflicts.

[openjdk]

@TobiHartmann Pushed as commit 8648890.

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