RFR: 8359394: Shenandoah: GC cause cleanup

[William Kemper]

On Thu, 12 Jun 2025 23:42:41 GMT, William Kemper <wkemper at openjdk.org> wrote:

> We can remove `GCCause::_no_cause_specified` and need to add a case for `_shenandoah_humongous_allocation_failure` in `GCCause::to_string`. We are also missing `_shenandoah_humongous_allocation_failure` in the `SA` analog.

src/hotspot/share/gc/shared/gcCause.cpp line 92:

> 90:       return "Diagnostic Command";
> 91: 
> 92:     case _shenandoah_stop_vm:

Just reordered this case to match enum's declaration order.

src/hotspot/share/gc/shared/gcCause.hpp line 118:

> 116:   inline static bool is_allocation_failure_gc(GCCause::Cause cause) {
> 117:     // _allocation_failure is the generic cause a collection for allocation failure
> 118:     return cause == GCCause::_allocation_failure;

Shenandoah does not use this method. Nobody else needs to know about this Shenandoah specific value.

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

PR Review Comment: https://git.openjdk.org/jdk/pull/25789#discussion_r2143900441
PR Review Comment: https://git.openjdk.org/jdk/pull/25789#discussion_r2143904488