Instruction Dispatching Jump Table

This idiomatic macro usage generates a jump table with eight entries, one each for AND, TAD, and so on. EQ is the CDC-6000's unconditinal jump instruction. The plus sign (+) insures that the jump is the first instruction of a new word, a placement called forced upper.
 INT5     NULL
+         EQ     OPR

PDP-8 Simulator
© 1975, 1998, Ward Cunningham
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