Request for reviews (M): 6614597: Performance variability in jvm2008 xml.validation

Vladimir Kozlov Vladimir.Kozlov at Sun.COM
Mon Jan 25 10:24:09 PST 2010


Reason_bimorphic will not cover the case when total counter
is larger then sum of 2 receivers in real bimorphic case.

What I am saying is currently the only reliable information
these counters can give us is monomorphic case. We can not
relay on them (in current implementation) to distinguish
bimorphic case from polimorphic case. This is why Reason_bimorphic
helps. If we use counters differently we don't need Reason_bimorphic.

Vladimir

John Rose wrote:
> On Jan 22, 2010, at 10:06 PM, Vladimir Kozlov wrote:
> 
>> The third solution (sorry they are still popping up) will be using
>> the total counter in MDO only for missing (third receiver) cases.
>> It will allow to keep current type profile width and distinguish
>> bimorphic case from polimorphic.
> 
> 
> I like Tom's idea of mapping Reason_bimorphic to an unrelated reason, such as Reason_range_check.
> 
> -- John
> 


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