GENERIC MODULE GT (Rep);

IMPORT CG, CallExpr, Expr, ExprRep, Procedure, Target, TWord;
IMPORT Bool, IntegerExpr, Value, Formal, Type, ProcType;
FROM Rep IMPORT T;
FROM TargetMap IMPORT Word_types;

VAR Z: CallExpr.MethodList;
VAR formals: Value.T;
VAR rep: [FIRST (Word_types) .. LAST (Word_types)];

PROCEDURE Check (ce: CallExpr.T;  VAR cs: Expr.CheckState) =
  BEGIN
    EVAL Formal.CheckArgs (cs, ce.args, formals, ce.proc);
    ce.type := Bool.T;
  END Check;

PROCEDURE Compile (ce: CallExpr.T) =
  BEGIN
    Expr.Compile (ce.args[0]);
    Expr.Compile (ce.args[1]);
    CG.Compare (Word_types[rep].cg_type, CG.Cmp.GT);
  END Compile;

PROCEDURE PrepBR (ce: CallExpr.T;  true, false: CG.Label;  freq: CG.Frequency)=
  BEGIN
    Expr.Prep (ce.args[0]);
    Expr.Prep (ce.args[1]);
    Expr.Compile (ce.args[0]);
    Expr.Compile (ce.args[1]);
    CG.If_then (Word_types[rep].cg_type, CG.Cmp.GT, true, false, freq);
  END PrepBR;

PROCEDURE Fold (ce: CallExpr.T): Expr.T =
  VAR w0, w1: Target.Int;
  BEGIN
    IF GetArgs (ce.args, w0, w1)
      THEN RETURN Bool.Map [TWord.LT (w1, w0)];
      ELSE RETURN NIL;
    END;
  END Fold;

PROCEDURE GetArgs (args: Expr.List;  VAR w0, w1: Target.Int): BOOLEAN =
  VAR e0, e1: Expr.T;  t: Type.T;
  BEGIN
    e0 := Expr.ConstValue (args[0]);
    e1 := Expr.ConstValue (args[1]);
    IF    (e0 # NIL) AND IntegerExpr.Split (e0, w0, t)
      AND (e1 # NIL) AND IntegerExpr.Split (e1, w1, t)
    THEN
      TWord.And (w0, Word_types[rep].max, w0);
      TWord.And (w1, Word_types[rep].max, w1);
      RETURN TRUE;
    ELSE
      RETURN FALSE;
    END;
  END GetArgs;

PROCEDURE Initialize (r: INTEGER) =
  VAR
    x1 := Formal.NewBuiltin ("x", 0, T);
    y1 := Formal.NewBuiltin ("y", 1, T);
    t1 := ProcType.New (Bool.T, x1, y1);
  BEGIN
    rep := r;
    Z := CallExpr.NewMethodList (2, 2, TRUE, TRUE, TRUE, Bool.T,
                                 NIL,
                                 CallExpr.NotAddressable,
                                 Check,
                                 CallExpr.PrepArgs,
                                 Compile,
                                 CallExpr.NoLValue,
                                 CallExpr.NoLValue,
                                 PrepBR,
                                 CallExpr.NoBranch,
                                 Fold,
                                 CallExpr.NoBounds,
                                 CallExpr.IsNever, (* writable *)
                                 CallExpr.IsNever, (* designator *)
                                 CallExpr.NotWritable (* noteWriter *));
    Procedure.Define ("GT", Z, FALSE, t1);
    formals := ProcType.Formals (t1);
  END Initialize;

BEGIN
END GT.