RFR: 8370691: Add new Float16Vector type and enable intrinsification of vector operations supported by auto-vectorizer [v5]

[Bhavana Kilambi]

On Mon, 8 Dec 2025 10:39:51 GMT, Emanuel Peter <epeter at openjdk.org> wrote:

>> test/hotspot/jtreg/compiler/vectorapi/TestFloat16VectorOperations.java line 134:
>> 
>>> 132:                            .intoArray(output, i);
>>> 133:         }
>>> 134:         for (; i < LEN; i++) {
>> 
>> Will this not result in autovectorization instead and also overwrite the `output` array results from vectorapi which were previously computed?
>
> Yes: there could be auto-vectorization.
> No: `i` is not reset, it keeps counting from where `i < SPECIES.loopBound(LEN)` fails, and handles the tail, right?
> 
> It could be good to run this test once with and once without auto vectorization, just to make sure the vectors you see are from the Vector API, and not auto vectorization.

Thanks. I missed that `i` isn't being reinitialised/reset again. Do we even need the tail loop in this case when the `LEN = 2048`? We may not even have any tail iterations?

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PR Review Comment: https://git.openjdk.org/jdk/pull/28002#discussion_r2598233546