Rotate Field Dispatching Jump Table

This idiomatic macro usage generates a jump table with eight entries, one each for the eight possible codes in the rotate field of the operate instruction.
 GP1.6    NULL
+         EQ     OPR
 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.

PDP-8 Simulator
© 1975, 1998, Ward Cunningham
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