RFR: 8351623: VectorAPI: Add SVE implementation of subword gather load operation [v3]

[Xiaohong Gong]

On Thu, 31 Jul 2025 13:55:12 GMT, Fei Gao <fgao at openjdk.org> wrote:

> > I've submitted a test on a 256-bit sve machine. I'll get back to you once it’s finished.
> 
> The new commit passed tier1 - tier3 on 256-bit `sve` machine without new failures. Thanks!

Thanks so much for your test!

> src/hotspot/cpu/arm/matcher_arm.hpp line 160:
> 
>> 158:   static const bool supports_encode_ascii_array = false;
>> 159: 
>> 160:   // Return true if vector gather-load/scatter-store needs vector index as input.
> 
> If the function returns `false`, does it indicate one of the following cases?
> - Vector gather-load or scatter-store does not accept a vector index for the current use case on this platform.
> - The current platform does not support vector gather-load or scatter-store at all.

Yes, I think so.

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PR Comment: https://git.openjdk.org/jdk/pull/26236#issuecomment-3141889356
PR Review Comment: https://git.openjdk.org/jdk/pull/26236#discussion_r2246712905