RFR: 8365153: AArch64: Set JVM flags for Neoverse N3 and V3 cores

[Evgeny Astigeevich]

On Fri, 8 Aug 2025 14:50:13 GMT, Ruben <duke at openjdk.org> wrote:

> For Neoverse N1, N2, V1, and V2, the following JVM flags are set:
>  - UseSIMDForMemoryOps=true
>  - OnSpinWaitInst=isb
>  - OnSpinWaitInstCount=1
>  - AlwaysMergeDMB=false
> 
> Additionally, for Neoverse V1 and V2 only, these flags are set:
>  - UseCryptoPmullForCRC32=true
>  - CodeEntryAlignment=32
> 
> Set the same flags for Neoverse N3 and V3, respectively.

Based on the available V3 and N3 optimization guides, we should expect similar or better performance on V3 and N3 when these changes are applied.

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Marked as reviewed by eastigeevich (Committer).

PR Review: https://git.openjdk.org/jdk/pull/26701#pullrequestreview-3245820561