RFR: 8374755: ML-KEM's 12-bit decompression can be simplified on aarch64

[Ferenc Rakoczi]

On Mon, 12 Jan 2026 10:37:31 GMT, Andrew Dinn <adinn at openjdk.org> wrote:

>> The preconditions for the aarch64 and the AVX-512 intrinsic implementations of the implKyber12To16() method of com.sun.crypto.provider.ML_KEM are different and the AVX-512 one has stricter preconditions on the input, which was not recorded in the assert() before calling the function (although they were satisfied by all calling code). Now the assert() is corrected, and with these preconditions, the aarch64 implementation is simplified.
>
> Changes look good. What testing have you run?

Thanks! @adinn would you be so kind as to /sponsor the integration?

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PR Comment: https://git.openjdk.org/jdk/pull/29141#issuecomment-3777775558