Tracing back objects

Hi,

The following code:
 CompiledMethod allInstances inject: (CompiledMethod allInstances first) into: 
[:m :i | i size > m size ifTrue: [i] ifFalse: [m]].

gives the largest method as an object. Is there an efficient way to trace back 
the method selector and its class without doing a brute force lookup?

TIA .. Subbu