Code generation.

[snipe.git] / trans / treeutils.sml

signature TREEUTILS =
sig
  val effect : Tree.exp -> bool
  val effect_stm : Tree.stm -> bool

  structure Print :
  sig
    val pp_exp : Tree.exp -> string
    val pp_stm : Tree.stm -> string
    val pp_program : Tree.program -> string
  end
end

structure TreeUtils :> TREEUTILS =
struct
  structure T = Tree

  (* effect : T.exp -> bool
   * true iff the given expression has an effect.
   *)
  fun effect (T.CONST _) = false
    | effect (T.TEMP _) = false
    | effect (T.ARG _) = false
    | effect (T.BINOP(T.DIV, _, _)) = true
    | effect (T.BINOP(T.MOD, _, _)) = true
    | effect (T.CALL _) = true
    | effect (T.BINOP(_, a, b)) = (effect a) orelse (effect b)
    | effect (T.UNOP (_, a)) = effect a
    | effect (T.MEMORY _) = true
    | effect (T.ALLOC _) = true
    | effect (T.COND (a, b, c)) = (effect a) orelse (effect b) orelse (effect c)
    | effect (T.STMVAR (sl, e)) = true (* Has to be, to be safe <--- jwise is an assclown, he was too lazy to write a effect_stm *)
    | effect (T.NULLPTR) = false

  fun effect_stm (T.MOVE (e1,e2)) = effect e1 orelse effect e2
    | effect_stm (T.RETURN (e1)) = effect e1
    | effect_stm (T.EFFECT e) = effect e
    | effect_stm (T.JUMPIFN (e,_)) = effect e
    | effect_stm _ = false

  structure Print = 
  struct
    exception Aaaasssssss

    fun pp_binop T.ADD = "+"
      | pp_binop T.SUB = "-"
      | pp_binop T.MUL = "*"
      | pp_binop T.DIV = "/"
      | pp_binop T.MOD = "%"
      | pp_binop T.LSH = "<<"
      | pp_binop T.RSH = ">>"
      | pp_binop T.LOGOR = "||"
      | pp_binop T.LOGAND = "&&"
      | pp_binop T.BITOR = "|"
      | pp_binop T.BITAND = "&"
      | pp_binop T.BITXOR = "^"
      | pp_binop T.NEQ = "!="
      | pp_binop T.EQ = "=="
      | pp_binop T.LE = "<="
      | pp_binop T.LT = "<"
      | pp_binop T.GE = ">="
      | pp_binop T.GT = ">"
      | pp_binop T.BE = "[BE]"
    
    fun pp_unop T.NEG = "-"
      | pp_unop T.BITNOT = "~"
      | pp_unop T.BANG = "!"

    fun pp_exp (T.CONST(x)) = Word32Signed.toString x
      | pp_exp (T.TEMP(t)) = Temp.name t
      | pp_exp (T.ARG(n)) = "arg#"^Int.toString n
      | pp_exp (T.BINOP (binop, e1, e2)) =
	  "(" ^ pp_exp e1 ^ " " ^ pp_binop binop ^ " " ^ pp_exp e2 ^ ")"
      | pp_exp (T.UNOP (unop, e1)) =
          pp_unop unop ^ "(" ^ pp_exp e1 ^ ")"
      | pp_exp (T.CALL (f, l)) =
          Symbol.name f ^ "(" ^ (String.concatWith ", " (List.map (fn e => pp_exp e) l)) ^ ")"
      | pp_exp (T.MEMORY (exp)) = "M[" ^ pp_exp exp ^ "]"
      | pp_exp (T.ALLOC(e)) = "NEW(" ^ pp_exp e ^ ")"
      | pp_exp (T.COND(c,e1,e2)) = "(" ^ pp_exp c ^ ") ? (" ^ pp_exp e1 ^ ") : (" ^ pp_exp e2 ^ ")"
      | pp_exp (T.STMVAR(sl,v)) = "({" ^ (foldr (fn (st,s) => (pp_stm st) ^ "; " ^ s) "" sl) ^ (pp_exp v) ^ "})"
      | pp_exp (T.NULLPTR) = "NULL"

    and pp_stm (T.MOVE (e1,e2)) =
	  pp_exp e1 ^ "  <--  " ^ pp_exp e2
      | pp_stm (T.RETURN (e)) =
	  "return " ^ pp_exp e
      | pp_stm (T.EFFECT e) = pp_exp e
      | pp_stm (T.LABEL l) =
          Label.name l ^ ":"
      | pp_stm (T.JUMP l) = 
          "jump "^Label.name l
      | pp_stm (T.JUMPIFN (e, l)) =
          "jump "^Label.name l^" if! "^pp_exp e

    fun pp_program (nil) = ""
      | pp_program (T.FUNCTION(id, stms)::funcs) =
          (Symbol.name id) ^
          "\n{\n" ^
          (foldr (fn (a,b) => (pp_stm a) ^ "\n" ^ b) "" stms) ^
          "}\n" ^
          pp_program funcs
  end
end