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
          ECHO   1,OPR=(AND,TAD,ISZ,DCA,JMS,JMP,IOT,OPR)
+         EQ     OPR
 
 

PDP-8 Simulator
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