RFR: 8367253: RISC-V: refactor dependent cpu extensions [v5]

[Hamlin Li]

On Mon, 29 Sep 2025 03:13:13 GMT, Fei Yang <fyang at openjdk.org> wrote:

>> Hamlin Li has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   minor
>
> src/hotspot/cpu/riscv/vm_version_riscv.cpp line 75:
> 
>> 73: 
>> 74: void VM_Version::initialize() {
>> 75:   ResourceMark rm;
> 
> What's this change for?

Thanks for catching. I'll remove it, seems it's useless in this version of the pr.

> src/hotspot/cpu/riscv/vm_version_riscv.hpp line 103:
> 
>> 101:     }
>> 102: 
>> 103:     void verify_deps(RVFeatureValue* dep0, ...) {
> 
> Not used anywhere?

Thanks for catching! I'll just remove it in this pr.

It should have been added in `UPDATE_DEFAULT_DEP(flag, dep0, ...)`, to do the similar work as the assert at https://github.com/openjdk/jdk/blob/master/src/hotspot/cpu/riscv/vm_version_riscv.hpp#L92. But seems previous way (introduced in https://github.com/openjdk/jdk/pull/24094) does not work as expected to catch declarations out of dependend orders, `verify_deps` does not catch it either as it inherits the way in the pr 24094.

I'll investigate it later and fix it in another pr.

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PR Review Comment: https://git.openjdk.org/jdk/pull/27171#discussion_r2387195064
PR Review Comment: https://git.openjdk.org/jdk/pull/27171#discussion_r2387195562