- GMOV _ _ -> True; GLD _ _ _ -> True; GST _ _ _ -> True
- GLDZ _ -> True; GLD1 _ -> True
- GFTOI _ _ -> True; GDTOI _ _ -> True
- GITOF _ _ -> True; GITOD _ _ -> True
- GADD _ _ _ _ -> True; GDIV _ _ _ _ -> True
- GSUB _ _ _ _ -> True; GMUL _ _ _ _ -> True
- GCMP _ _ _ -> True; GABS _ _ _ -> True
- GNEG _ _ _ -> True; GSQRT _ _ _ -> True
- GSIN _ _ _ _ _ -> True; GCOS _ _ _ _ _ -> True; GTAN _ _ _ _ _ -> True
- GFREE -> panic "is_G_instr: GFREE (!)"
- other -> False