tree.sml

signature TREE = 
sig 
  type label = Temp.label
  type size

datatype stm = SEQ of stm * stm
             | LABEL of label
             | JUMP of exp * label list
             | CJUMP of relop * exp * exp * label * label
             | MOVE of exp * exp
             | EXP of exp

     and exp = BINOP of binop * exp * exp
             | MEM of exp
             | TEMP of Temp.temp
             | ESEQ of stm * exp
             | NAME of label
             | CONST of int
             | CALL of exp * exp list

      and binop = PLUS | MINUS | MUL | DIV 
                | AND | OR | LSHIFT | RSHIFT | ARSHIFT | XOR

      and relop = EQ | NE | LT | GT | LE | GE 
	        | ULT | ULE | UGT | UGE

  val notRel : relop -> relop
  val commute: relop -> relop
end

structure Tree : TREE = 
struct
  type label=Temp.label
  type size = int

datatype stm = SEQ of stm * stm
             | LABEL of label
             | JUMP of exp * label list
             | CJUMP of relop * exp * exp * label * label
             | MOVE of exp * exp
             | EXP of exp

     and exp = BINOP of binop * exp * exp
             | MEM of exp
             | TEMP of Temp.temp
             | ESEQ of stm * exp
             | NAME of label
             | CONST of int
             | CALL of exp * exp list

      and binop = PLUS | MINUS | MUL | DIV 
                | AND | OR | LSHIFT | RSHIFT | ARSHIFT | XOR

      and relop = EQ | NE | LT | GT | LE | GE 
	        | ULT | ULE | UGT | UGE

  fun notRel EQ = NE
    | notRel NE = EQ
    | notRel LT = GE
    | notRel GT = LE
    | notRel LE = GE
    | notRel GE = LT
    | notRel ULT = UGE
    | notRel ULE = UGT
    | notRel UGT = ULE
    | notRel UGE = ULT

  fun commute EQ = EQ
    | commute NE = NE
    | commute LT = GT
    | commute GT = LT
    | commute LE = GE
    | commute GE = LE
    | commute ULT = UGT
    | commute ULE = UGE
    | commute UGT = ULT
    | commute UGE = ULE
end