Dynamically reconfigurable architectures offer the opportunity to migrate software into hardware functional units at runtime. Architectures derived from the AMIDAR model exhibit such possibilities. In previous work we have shown how to identify heavily used code sequences and have also shown that it might be interesting to synthesize hardware for a set of methods of one class and also cache the state of particular objects in the synthesized hardware. In this paper we discuss a method to identify such objects at runtime and present a heuristics to select caching candidates in order to make optimal use of the limited storage resources.