On Fri, 5 Jun 2026 20:15:30 GMT, Shawn Emery <[email protected]> wrote:
> Curve25519 polynomial arithmetic is performed with intrinsincs implemented in > GPR related instructions for multiplication operations (method mult()). > Benchmark improvements include: > > X25519 decapsulation: +9% > X25519 encapsulation: +9% > X22519 key agreement: +7% > X25519 key-pair generation: +10% > X25519-MLKEM decapsulation: +7% > X25519-MLKEM encapsulation: +8% > X25519-MLKEM key-pair generation: +8% > EdDSA sign: +12% > EdDSA verify: +12% > EdDSA key-pair generation: +15% > > Note 1: The difference between Aarch64 vs. x86_64 intrinsics implementation > include the lack of square() intrinsics; usage caused a 3.3% performance > regression due to the efficiencies of the symmetric squaring shape in Java > vs. the inefficiencies of the leaf calls and the additional cycles required > for 64 bit multiplication in Aarch64. > Note 2: The GPR related instructions were optimal when compared to hybrid > (GPR related instructions for the first two iterations and Neon instructions > for the last two iterations) solution. This design produced a -4%/-1% > performance drop in KEM decapsulation/encapsulation compared to the GPR > related instructions where the overhead of performing the limb splits and > reconstruction did not compensate enough for the efficiencies of SIMD > parallelism. > > --------- > - [X] I confirm that I make this contribution in accordance with the [OpenJDK > Interim AI Policy](https://openjdk.org/legal/ai). Triggering security-dev email. ------------- PR Comment: https://git.openjdk.org/jdk/pull/31409#issuecomment-4636639573
