RFR: 8286847: Rotate vectors don't support byte or short [v3]

[Haomin]

On Wed, 18 May 2022 04:12:39 GMT, Xiaohong Gong <xgong at openjdk.org> wrote:

>> Haomin has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   merge the two cases into one
>
> src/hotspot/share/opto/vectornode.cpp line 158:
> 
>> 156:     default:     return 0; // RotateLeftV for byte, short values produces incorrect Java result.
>> 157:                            // Because java code should convert a byte, short value into int value,
>> 158:                            // and then do RotateI.
> 
> I‘m afraid this will influence the VectorAPI intrinsification for `ByteVector `and `ShortVector`. Did you test the benchmarks for these two APIs with the subword type?

I have tested `hotspot_vector_1` and `jdk_vector`, all pass.

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PR: https://git.openjdk.java.net/jdk/pull/8740