RFR: 8354890: AOT-initialize j.l.i.MethodHandleImpl and inner classes

[Andrew Dinn]

On Tue, 29 Apr 2025 22:59:29 GMT, Ioi Lam <iklam at openjdk.org> wrote:

> This is a general fix for all the "points to a static field that may hold a different value" failures related to `java/lang/invoke/MethodHandleImpl`. E.g., [JDK-8354840](https://bugs.openjdk.org/browse/JDK-8354840), [JDK-8353330](https://bugs.openjdk.org/browse/JDK-8353330).
> 
> AOT-cached method handles quite often refer to the static fields in `MethodHandleImpl` or its inner classes. In the production run, if the value of these static field changes, we may have unexpected behavior related to identity of objects in these static fields. `CDSHeapVerifier` makes a very conservative check for such static fields, but sometimes gives false positives (as in the above two JBS issues)
> 
> In this PR, we AOT-initialize `MethodHandleImpl` and its inner classes. This is a more authentic snapshot of the state of `java.lang.invoke` during the assembly phase. We also avoid the need to add and maintain entries in the `cdsHeapVerifier.cpp` table.
> 
> I also added more code in `MethodHandleTest.java` to simulate potential usage patterns of `MethodHandle` by the Java core libraries. Hopefully this will reduce the likelihood for innocent core lib changes breaking the AOT assembly phase.

@iklam We have seen this problem with Red Hat deployments in jdk24 as well as jdk25-ea.

I'm saying that mostly for information. However, I do have to ask: If this is fixed for jdk25 is there any question of also fixing it in jdk24? I would be content to receive a no answer -- a similar issue with patch that could be backported from jdk26 -> jdk25 might be something to think about a bit more?

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PR Comment: https://git.openjdk.org/jdk/pull/24956#issuecomment-2845492119