111xxx - debug functions
111000 ----- dump heap (debug.pvvs)
111001 ----- dump stack (debug.pvvs)
+ 111010 ----- print sign (debug.pvvs)
+ 111011 ----- print magnitude (debug.pvvs)
+ 111100 ----- print string (debug.pvvs)
1xxxxxx - reserved for less common entry points
1000000 ----- lowbitand (logic.pvvs)
1000001 ----- isnegative (math.pvvs)