RFR: 8322174: RISC-V: C2 VectorizedHashCode RVV Version [v20]

[Yuri Gaevsky]

On Wed, 6 Aug 2025 15:08:50 GMT, Yuri Gaevsky <duke at openjdk.org> wrote:

>> The patch adds possibility to use RVV instructions for faster vectorizedHashCode calculations on RVV v1.0.0 capable hardware.
>> 
>> Testing: hotspot/jtreg/compiler/ under QEMU-8.1 with RVV v1.0.0.
>
> Yuri Gaevsky has updated the pull request incrementally with one additional commit since the last revision:
> 
>   try m4 for grouping

`424a453`:

--- -XX:+UseRVV ---
Benchmark            (size)  Mode  Cnt     Score    Error  Units
ArraysHashCode.ints       1  avgt   30    11.277 ±  0.005  ns/op
ArraysHashCode.ints       5  avgt   30    21.333 ±  0.032  ns/op
ArraysHashCode.ints      10  avgt   30    33.850 ±  0.019  ns/op
ArraysHashCode.ints      20  avgt   30    44.479 ±  0.015  ns/op
ArraysHashCode.ints      30  avgt   30    69.189 ±  0.149  ns/op
ArraysHashCode.ints      40  avgt   30    60.135 ±  0.049  ns/op
ArraysHashCode.ints      50  avgt   30    53.870 ±  0.007  ns/op
ArraysHashCode.ints      60  avgt   30    76.410 ±  0.015  ns/op
ArraysHashCode.ints      70  avgt   30    67.745 ±  0.495  ns/op
ArraysHashCode.ints      80  avgt   30    58.244 ±  0.008  ns/op
ArraysHashCode.ints      90  avgt   30    79.313 ±  0.063  ns/op
ArraysHashCode.ints     100  avgt   30    74.461 ±  1.249  ns/op
ArraysHashCode.ints     200  avgt   30   122.614 ±  1.878  ns/op
ArraysHashCode.ints     300  avgt   30   160.973 ±  0.069  ns/op
ArraysHashCode.ints    1000  avgt   30   423.633 ± 11.864  ns/op
ArraysHashCode.ints   10000  avgt   30  5938.320 ± 56.340  ns/op

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PR Comment: https://git.openjdk.org/jdk/pull/17413#issuecomment-3160779885