RFR: 8357223: AArch64: Optimize interpreter profile updates [v2]

[Aleksey Shipilev]

On Thu, 29 May 2025 23:04:25 GMT, Chad Rakoczy <duke at openjdk.org> wrote:

>> [JDK-8357223](https://bugs.openjdk.org/browse/JDK-8357223)
>> 
>> The aarch64 version of [JDK-8356946](https://bugs.openjdk.org/browse/JDK-8356946)
>> 
>> The reasoning for this change is the same as the x86 version's PR:
>> 
>>> 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.
>> 
>> Additional testing:
>> 
>> - [x] Linux aarch64 fastdebug tier 1/2/3/4
>
> Chad Rakoczy has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Address comments

I would like @theRealAph to ack this before I sponsor.

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PR Comment: https://git.openjdk.org/jdk/pull/25512#issuecomment-2934132868