RFR: 8357424: [JVMCI] Avoid incrementing decompilation count for hosted compiled nmethod [v4]

[Yudi Zheng]

On Tue, 27 May 2025 17:30:09 GMT, Tom Rodriguez <never at openjdk.org> wrote:

>> Yudi Zheng has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   address comments
>
> I think there are two levels of counters that we might want to disable.  We definitely want to stop deopts and recompilations from marking the method not compilable which the current change does.  Additionally JVMCIRuntime::register_method will perform this logic if validate_compile_task_dependencies fails and I don't think we want that.  I think the new `!is_default` guard idiom should be in a helper like `nmethod::is_jvmci_hosted`.  Do we use the hosted language elsewhere?
> 
> The second level is to stop all counter updates in hosted compiles, for similar reasons.  Those updates won't lead to disabling compilation but they will quickly lead to saturating of all the counters which is fairly pointless but probably benign.  This would be done by setting `update_trap_state` to false for hosted nmethods.  That also has the effect of keeping `inc_recompile_count` false.  I think that's the right thing to do but I'd want to make sure that we test truffle workloads with those changes before making that change to make sure there isn't some subtle problem with that change.

@tkrodriguez by `stop all counter updates in hosted compiles` you mean the trap-related counters, right?

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PR Comment: https://git.openjdk.org/jdk/pull/25356#issuecomment-2963536923