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M.A. Ertl:
"Threaded Code Variations and Optimizations (Extended Version)";
Talk: FORTH-Tagung 2002, Garmisch-Partenkirchen; 2002-04-18 - 2002-04-21; in: "FORTH-Tagung 2002", (2002), 1 - 7.

Forth has been traditionally implemented as indirect threaded code, where the code for non-primitives is the code-field address of the word. To get the maximum benefit from combining sequences of primitives into superinstuctions, the code produced for a non-primitive should be a primitive followed by a parameter ( e.g., lit addr for variables). This paper takes a look at the steps from a tratitional threaded-code implementation to superinstructions, and at the size and speed effects of the various steps. The use of superinstructions gives speedups of up to a factor of 2 on large benchmarks on processors with branch target buffers, but requires more space for the primitives and the optimization tables, and also a little more space for the threaded code.