AOT caching of WeakReference

[ioi.lam at oracle.com]

On 11/14/24 1:48 PM, ioi.lam at oracle.com wrote:
> Here's my  experiment with storing weak references in the AOT cache
>
> https://github.com/iklam/jdk/blob/8341587-example-of-weakref-problem-in-aot-cache/AOT-Cache-And-WeakRef.md 
>
>
> As discussed in the Leyden meeting today, there seem to be at least 
> two issues
>
> - In premain, CDS keeps every archived heap object alive (look for 
> UsePermanentHeapObjects in the code). I plan to get rid of this 
> shortly. UsePermanentHeapObjects is intended for the AOT compiler to 
> access heap objects, but it should be implemented differently (only 
> remember objects that are required by AOT code, which should include 
> only Strings and class mirrors).
>

I have fixed UsePermanentHeapObjects so that only objects that are 
referenced by AOT-compiled methods are kept alive.

See 
https://git.openjdk.org/leyden/commit/ac533a7e29810400fd6ccbbeab01e478dfd2f9ac