RFR: 8369685: RISC-V: refactor code related to RVFeatureValue::enabled [v2]

[Hamlin Li]

On Wed, 15 Oct 2025 06:07:38 GMT, Robbin Ehn <rehn at openjdk.org> wrote:

>> src/hotspot/cpu/riscv/vm_version_riscv.cpp line 201:
>> 
>>> 199:   if (UseZicboz && zicboz_block_size.enabled()) {
>>> 200:     assert(is_power_of_2(zicboz_block_size.value()) &&
>>> 201:            zicboz_block_size.value() > 0, "Sanity");
>> 
>> Note the previous discussion about why we need this `> 0` check [1].
>> @robehn mentions that the kernel seems to have a bug: if it can't retrive those value it will return 0 as value for those.
>> 
>> So maybe simply do:
>> 
>> if (UseZicboz && zicboz_block_size.value() > 0) {
>>   assert(is_power_of_2(zicboz_block_size.value()), "Sanity");
>>   ......
>> 
>> 
>> [1] https://github.com/openjdk/jdk/pull/27155#issuecomment-3270608461
>
> Yes, it seems like we need to check these for a non 0 value.

OK, will fix.

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PR Review Comment: https://git.openjdk.org/jdk/pull/27771#discussion_r2431639081