[aarch64-port-dev ] RFC: JEP - One AArch64 Port, Not Two

[Ningsheng Jian]

On 27 August 2018 at 17:00, Andrew Haley <aph at redhat.com> wrote:
> On 08/27/2018 09:49 AM, Ningsheng Jian wrote:
>> Yes, some benchmark data is unstable. We did analyze the arm64 and
>> aarch64 codegen difference with microbenchmarks. AArch64 backend
>> generates better code on most cases, and I believe that we have
>> addressed those minor worse cases we found. E.g. JDK-8183533,
>> JDK-8185786, JDK-8187601.
>
> Mmm, and it's not really possible to show for sure that changes
> generalize well. I'm still not convinced by tweaks to unrolling,
> but they work spectacularly well in some small benchmarks.
>

I just searched our work log and found those items. At least they were
exposed by microbenchmarks [1] we analyzed where arm64 performed
better than AArch64. Yes, they are just small benchmarks. :-)

[1] https://git.linaro.org/leg/openjdk/jmh-linaro-org.git

Thanks,
Ningsheng