Please review fix for 7195867: NPG: SAJDI tests fail with sun.jvm.hotspot.types.WrongTypeException: No,suitable match for type

Coleen Phillimore coleen.phillimore at
Wed Sep 5 18:42:37 PDT 2012

Thank you for your code review, and for checking out the new version.

On 9/5/2012 9:23 PM, Karen Kinnear wrote:
> Coleen,
> Much nicer. Wish I'd thought of those improvements.
> thanks,
> Karen
> On Sep 5, 2012, at 7:27 PM, Coleen Phillimore wrote:
>> How about this version - hit reload.   I think it makes it more obvious.
>> thanks,
>> Coleen
>> On 9/5/2012 5:37 PM, John Coomes wrote:
>>> Coleen Phillimore (coleen.phillimore at wrote:
>>>> Summary: Need to restore the vtable in metadata when we restore the type
>>>> from the shared archive.
>>>> When dumping the shared archive all the C++ vtables are patched to be a
>>>> piece of code that inserts the actual vtable in the type, and calls
>>>> through the actual vtable to where the function was restored.   SA uses
>>>> the address of the vtable to determine which metadata type it is looking
>>>> at.  By calling one virtual function during restore, we can restore the
>>>> c++ vtable to the actual one so SA can match it.
>>> This code is executed solely to trigger a non-obvious side effect; i'd
>>> like to see that made much more explicit (preferably in the code, but
>>> at least in a comment).  Otherwise, I'm sure someone will be tempted
>>> to remove the "useless" guarantee someday.
>>> In the code you can add a simple method (e.g., restore_vtable() or
>>> similar) that wraps the virtual call.
>>> Aside from that, looks good.
>>> -John
>>>> (systemDictionary is a whitespace change).
>>>> Tested sajdi tests.
>>>> Thanks,
>>>> Coleen

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