RFR: 8373599: Cleanup arguments.hpp includes [v2]

[David Holmes]

On Fri, 12 Dec 2025 15:06:39 GMT, Stefan Karlsson <stefank at openjdk.org> wrote:

>> In the Valhalla project we are considering using a property in Arguments to figure out if Valhalla is enabled. To minimize transitive-include-proliferation if this property ever needs to be checked in a header I propose that we clean up the header includes in arguments.hpp.
>> 
>> I'm opening the review for this so that I can get opinions on the move of functions. I'm going to compile this on all our platforms and will likely add a few more includes when unrelated files fail to compile because they relied on the includes provided through by java.hpp and arguments.hpp.
>
> Stefan Karlsson has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Sort order

I don't understand the motivation here. Why do we not have a global `UseValhalla` the way we have `UseXXX` for so many things. Including `argument.hpp` to ask `is_valhalla_enabled()` doesn't seem appropriate to me.

That said does it even make sense to use the word "Valhalla" here? Today I assume it means JEP-401 but next release? and the one after?

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PR Comment: https://git.openjdk.org/jdk/pull/28791#issuecomment-3653605828