Optimizing Smalltalk by Selector Code Indexing Can Be Practical

Selector code indexing is a simple and effective way of optimizing method lookups.
However, it has not been considered practically applicable in Smalltalk,
because the space overhead is prohibitive. We proposed a new technique called
dispatch caches indexed by selector codes (CISCO), which maintains a small number of dispatch tables indexed by a small number of selector codes. The space overhead is thus a small constant, however many classes and selectors there are in a system,
while it almost maintains the runtime efficiency of selector code indexing. An implementation achieves over 50% speedup in method lookups for the set of programs
in the Smopstone benchmark.