8383635: Improve performance of ML-KEM's implKyberNttMultJava() method

[stooke]

I would like to backport this enhancement to JDK25 as part of a series of Post Quantum Cryptography PRs. This PR enhances the performance of the ML-KEM implementation so should be part of this ongoing effort.

Medium to low risk.

[Testing]
Tier 2 tests pass, except for several network related tests that also fail in the master branch on my machine.
Specifically, acvp/Launcher.java passes with the ACVP-Server-1.1.0.38 bundle supplied.

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Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8383635 needs maintainer approval

Issue

• JDK-8383635: Improve performance of ML-KEM's implKyberNttMultJava() method (Enhancement - P4)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk25u-dev.git pull/760/head:pull/760
$ git checkout pull/760

Update a local copy of the PR:
$ git checkout pull/760
$ git pull https://git.openjdk.org/jdk25u-dev.git pull/760/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 760

View PR using the GUI difftool:
$ git pr show -t 760

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk25u-dev/pull/760.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back stooke! 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]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

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

[openjdk]

⚠️ @stooke 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.

[mlbridge]

Webrevs

• 00: Full (cc3b505a)