RFR: 8351700: Remove code conditional on BarrierSetNMethod being null [v3]

[Doug Simon]

On Wed, 12 Mar 2025 09:16:44 GMT, Doug Simon <dnsimon at openjdk.org> wrote:

>> All GCs started needing nmethod entry barriers as of loom so there's no longer any need to test for null nmethod entry barriers.
>
> Doug Simon has updated the pull request incrementally with one additional commit since the last revision:
> 
>   removed unused code

`gc/TestAllocHumongousFragment.java#generational` is failing on Windows: https://github.com/dougxc/jdk/actions/runs/13807682996/job/38625487569#step:9:630
I don't think it can be caused by this PR. Are you able to confirm that @shipilev ?

-------------

PR Comment: https://git.openjdk.org/jdk/pull/23996#issuecomment-2717699848