RFR: 8310949: RISC-V: Initialize UseUnalignedAccesses [v3]

[Fei Yang]

On Tue, 27 Jun 2023 14:00:31 GMT, Ludovic Henry <luhenry at openjdk.org> wrote:

>> 8310949: RISC-V: Initialize UseUnalignedAccesses
>
> Ludovic Henry has updated the pull request incrementally with one additional commit since the last revision:
> 
>   fixup! 8310949: RISC-V: Initialize UseUnalignedAccesses

We will need some performance numbers to validate this change. We witnessed some obvious regressions of Unsafe.Put*Unaligned methods when enabling UseUnalignedAccesses on some platforms like HiFive Unmatched with slow unaligned accesses. My guess is that we might want enable UseUnalignedAccesses for platforms like T-Head with fast unaligned accesses (RISCV_HWPROBE_MISALIGNED_FAST). But that will still depend on the measured JMH numbers.

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

PR Comment: https://git.openjdk.org/jdk/pull/14676#issuecomment-1610687733