RFR: 8377126: Shenandoah: Convert ShenandoahVerifier related code to use Atomic<T>

[Aleksey Shipilev]

On Wed, 4 Feb 2026 18:20:18 GMT, Ben Taylor <btaylor at openjdk.org> wrote:

> Modernizes ShenandoahVerifier code by replacing `AtomicAccess` methods with `Atomic<T>` types.
> 
> Tier1 test results on x86_64 linux are the same before and after this change when running with `TEST_VM_OPTS=-XX:+UseShenandoahGC`.

src/hotspot/share/gc/shenandoah/shenandoahVerifier.cpp line 667:

> 665:     }
> 666: 
> 667:     _processed.add_then_fetch(processed);

Lost `memory_order_relaxed` here?

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PR Review Comment: https://git.openjdk.org/jdk/pull/29576#discussion_r2767523123