type token_UTYPE    = {op : riscvUop }
type token_JAL      = unit
type token_JALR     = unit
type token_BType    = {op : riscvBop }
type token_IType    = {op : riscvIop }
type token_ShiftIop = {op : riscvSop }
type token_RTYPE    = {op : riscvRop }
type token_Load     = {unsigned: bool; width : wordWidth; aq: bool; rl: bool }
type token_Store    = {width : wordWidth; aq: bool; rl: bool }
type token_ADDIW    = unit
type token_SHIFTW   = {op : riscvSop }
type token_RTYPEW   = {op : riscvRopw }
type token_FENCE    = unit
type token_FENCETSO = unit
type token_FENCEI   = unit
type token_LoadRes  = {width : wordWidth; aq: bool; rl: bool }
type token_StoreCon = {width : wordWidth; aq: bool; rl: bool }
type token_AMO      = {width : wordWidth; aq: bool; rl: bool; op: riscvAmoop }

type token_FENCEOPTION = Fence_R | Fence_W | Fence_RW

(* pseudo-ops *)

type token_LI = unit