RFR: 8300865: C2: product reduction in ProdRed_Double is not vectorized [v3]

Wed May 31 00:48:59 UTC 2023

On Tue, 30 May 2023 07:59:37 GMT, Emanuel Peter <epeter at openjdk.org> wrote:

>> Thanks a lot @eme64.
>
> @sviswa7 testing to tier5 and stress testing looks good.
> 
> Out of curiosity: do you have a benchmark that shows a speedup with this change? Would be nice to add it.
> Maybe we could start with a benchmark from  https://git.openjdk.org/jdk/pull/13056 and add some more compute-instructions to outweigh the latency of the reduction? Not sure if that is very easy.

Thanks a lot @eme64. There was an existing jmh benchmark for vector reduction. I have updated it to add double reduction case.

-------------

PR Comment: https://git.openjdk.org/jdk/pull/14065#issuecomment-1569329896