RFR: 8351748: Add class init barrier to AOT-cached Method/Var Handles

[Ioi Lam]

On Thu, 13 Mar 2025 16:51:36 GMT, Vladimir Ivanov <vlivanov at openjdk.org> wrote:

>>> IMO a safer alternative is to unconditionally keep all clinit barriers during assembly phase (irrespective of whether relevant class is initialized or not).
>> 
>> Could you elaborate how this can be done?
>
>> Could you elaborate how this can be done?
> 
> For `MethodHandle`s `DirectMethodHandle.shouldBeInitialized(Class)` determines whether a barrier is needed or not. It can be tweaked to behave conservatively during assembly phase and report `true` irrespective of whether the target class is initialized or not. (And it can take AOT-inited classes into account as well.) 
> 
> (`VarHandle`s use `Unsafe.shouldBeInitialized(Class)` directly.)

Thanks @iwanowww @liach for the review

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PR Comment: https://git.openjdk.org/jdk/pull/24004#issuecomment-2747045729