CHA for interfaces in C2 compiler

John Rose john.r.rose at oracle.com
Thu Apr 16 06:56:24 UTC 2015


The real cost of the type check is a cache line fetch. In this case you have a bunch of objects whose code is the same method(s) and data fields are the only way to vary the behavior. So almost any plausible application of this pattern will need the same cache line as the data fields.

We have yet to see a convincing use case for this CHA (THA) case.  I put some code in the VM to support this once but we never needed it and it was removed. 

(Another opt with a similar flavor would be support for the singleton pattern.)

– John

> On Apr 15, 2015, at 8:05 PM, Vitaly Davidovich <vitalyd at gmail.com> wrote:
> 
> That would certainly be a place where removing the type check would be beneficial


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