RFR: 8292914: Drop the counter from lambda class names [v6]

[Mandy Chung]

On Thu, 16 Feb 2023 19:35:54 GMT, David M. Lloyd <duke at openjdk.org> wrote:

>> The class generated for lambda proxies is now defined as a hidden class. This means that the counter, which was used to ensure a unique class name and avoid clashes, is now redundant. In addition to performing redundant work, this also impacts build reproducibility for native image generators which might already have a strategy to cope with hidden classes but cannot cope with indeterminate definition order for lambda proxy classes.
>> 
>> This solves JDK-8292914 by making lambda proxy names always be stable without any configuration needed. This would also replace #10024.
>
> David M. Lloyd has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Use a unique index for the dumped lambda class instead of a time stamp

`this_class` in the classbyte is shown in the VM logging (`-Xlog:class+nestmates=debug`).  It'd be helpful if it can easily correlate to the dumped file.   For example, 3 lambda proxy classes of the same name of `this_class` but they are unique hidden classes.


0.058s][info ][class,nestmates] LookupDefineClass: jdk/internal/module/DefaultRoots$$Lambda$ - with dynamic nest-host jdk.internal.module.DefaultRoots, hidden, strong, with vm annotations
[0.058s][debug][class,nestmates] Dynamic nestmate: java.base/jdk.internal.module.DefaultRoots$$Lambda$/0x000000080000a970, nest_host jdk.internal.module.DefaultRoots, is hidden
[0.062s][info ][class,nestmates] LookupDefineClass: jdk/internal/module/DefaultRoots$$Lambda$ - with dynamic nest-host jdk.internal.module.DefaultRoots, hidden, strong, with vm annotations
[0.062s][debug][class,nestmates] Dynamic nestmate: java.base/jdk.internal.module.DefaultRoots$$Lambda$/0x000000080000b998, nest_host jdk.internal.module.DefaultRoots, is hidden
[0.068s][info ][class,nestmates] LookupDefineClass: jdk/internal/module/DefaultRoots$$Lambda$ - with dynamic nest-host jdk.internal.module.DefaultRoots, hidden, strong, with vm annotations
[0.068s][debug][class,nestmates] Dynamic nestmate: java.base/jdk.internal.module.DefaultRoots$$Lambda$/0x000000080000c0b0, nest_host jdk.internal.module.DefaultRoots, is hidden


What about keeping your original idea - the filename matching the hidden class name if successfully defined.   If it fails at `defineHiddenClass` time, use `lambdaClassName` + counter? 

Also, `test/jdk/java/lang/StackWalker/VerifyStackTrace.java` tests need update because of the lambda proxy class name change.

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PR: https://git.openjdk.org/jdk/pull/12579