RFR (XS): JDK-6563994 - assert(wf.check_method_context(ctxk, m), "proper context") failed

[S. Bharadwaj Yadavalli]

Thanks for the reviews, Christian and Vladimir.

Bharadwaj

On 05/19/2014 01:33 PM, Vladimir Kozlov wrote:
> Good.
>
> Vladimir
>
> On 5/19/14 8:42 AM, S. Bharadwaj Yadavalli wrote:
>> I would like to get reviews for a small fix for the occasional nightly
>> failures reported in
>> https://bugs.openjdk.java.net/browse/JDK-6563994
>>
>> The assertion is observed to be triggered while looking up for a
>> monomorphic call target. It happens in a rare
>> situation, where the method holder class is redefined at safepoints
>> *after* resolution of the target method's class (in
>> find_monomorphic_target() - src/share/vm/ci/ciMethod.cpp:694) but
>> *before* the call of find_unique_concrete_method() -
>> src/share/vm/ci/ciMethod.cpp:733). This change returns NULL for a such
>> a redefined method which would be marked as old,
>> indicating that candidate call target may not be inlined, since all we
>> have is a pointer to an old method that has been
>> redefined. The subsequent assertion of check_method_context for old
>> methods is not applicable and hence not done for
>> such methods.
>>
>> Testing:
>>
>> Without the fix: Was able to trigger the assertion upon running the
>> test nsk.jvmti.RetransformClasses.retransform001 a
>> few hundred times.
>>
>> With the fix: Was able to run the test for over 3000 iterations
>> continuously for more than 3 days without triggering the
>> assertion.
>>
>> Ran JPRT tests successfully
>>
>> webrev: http://cr.openjdk.java.net/~bharadwaj/6563994/webrev_0/
>> bug: https://bugs.openjdk.java.net/browse/JDK-6563994
>>
>> Thanks,
>>
>> Bharadwaj