RFR: 8358105: RISC-V: Optimize interpreter profile updates

[Anjian Wen]

On Tue, 3 Jun 2025 09:27:39 GMT, Feilong Jiang <fjiang at openjdk.org> wrote:

>> The reason of this patch is same as the x86 and aarch64 but for riscv
>> [JDK-8356946](https://bugs.openjdk.org/browse/JDK-8356946)
>> [JDK-8357223](https://bugs.openjdk.org/browse/JDK-8357223)
>> 
>>> First, we carry the implementation for counter decrements without using them. This is dead code, and can be purged. Second, we care about overflows for 64-bit for some reason. I think this is a reminiscent of 32-bit x86 support, where we can plausibly have 32-bit counter overflow in a reasonable timeframe. But for 64-bit counter, we need tens of years of constantly bashing the counter to get it to overflow. No other profile counter update code, e.g. in C1, cares about this.
>
> Looks good!

@feilongjiang @RealFYang  Thanks for your review and comments！

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PR Comment: https://git.openjdk.org/jdk/pull/25520#issuecomment-2938043407