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(GE) = LT
  | notRel(LE) = GT
  | notRel(GT) = LE
  | notRel(ULT) = UGE
  | notRel(UGE) = ULT
  | notRel(ULE) = UGT
  | notRel(UGT) = ULE

end

structure Tr = Tree