On Mon, 2 Nov 2026 15:41:02 GMT, Stuart Monteith <[email protected]> wrote:
>> A trivial fix that checks that the system supports Neon-based instructions >> before generating stubs for conditional assigns and P-256 field operations. >> >> --------- >> - [X] I confirm that I make this contribution in accordance with the >> [OpenJDK Interim AI Policy](https://openjdk.org/legal/ai). > > To clarify, the Arm ARM does state that Advanced SIMD is OPTIONAL for Arm > v8.0, however "standard operating systems" with "rich application > environments" require Advanced SIMD. Anything that can run OpenJDK can be > expected to have it.. The AAPCS64 explicitly requires Advanced SIMD, so any > programs compiled against that can expect it. > > The UseIntPolyIntrinsics appears to add UMULL, UMULL2, which are standard and > don't need to detect Advanced SIMD. > > Instructions that are specifically for cryptography (SHA, AES, SM3/4, PMULL) > should be detected as they aren't guaranteed to be included. > > So I agree with the removal of this feature detection for Advanced SIMD, it > is redundant. @stooart-mon Thanks for clarifying. Given that Linux and Windows on AArch64 both assume AAPCS64 I think we can assume the ASIMD feature is present. In the RFE mentioned above I recommended adding an assert that the feature is present (extra braces to augment the security offered by that belt). ------------- PR Comment: https://git.openjdk.org/jdk/pull/33661#issuecomment-6581945663
