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

Karen Kinnear karen.kinnear at
Wed Sep 5 18:23:41 PDT 2012


Much nicer. Wish I'd thought of those improvements.


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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