> When a primitive operation returns, much of the time control soon passes to another primitive operation, staying near the bottom of the tree.
Depending on how the threading is implemented, the primitive "return" (NEXT) operation may even pass control directly to the next primitive; a typical threaded implementation of NEXT might be something along the lines of "load next codeword and branch to it". You only go through the full call/return sequence, e.g. updating the return stack, when entering or leaving a non-primitive word.
Depending on how the threading is implemented, the primitive "return" (NEXT) operation may even pass control directly to the next primitive; a typical threaded implementation of NEXT might be something along the lines of "load next codeword and branch to it". You only go through the full call/return sequence, e.g. updating the return stack, when entering or leaving a non-primitive word.