File: WordAnd.m3 Last Modified On Mon Dec 5 15:19:35 PST 1994 By kalsow Modified On Tue Apr 10 11:06:36 1990 By muller
MODULE; IMPORT CG, CallExpr, Expr, ExprRep, Procedure, ProcType; IMPORT IntegerExpr, Formal, Value, Target, TWord, TInt; FROM Int IMPORT T; IMPORT WordPlus AS Plus; VAR Z: CallExpr.MethodList; VAR formals: Value.T; PROCEDURE WordAnd Check (ce: CallExpr.T; VAR cs: Expr.CheckState) = BEGIN EVAL Formal.CheckArgs (cs, ce.args, formals, ce.proc); ce.type := T; END Check; PROCEDURECompile (ce: CallExpr.T) = BEGIN Expr.Compile (ce.args[0]); Expr.Compile (ce.args[1]); CG.And (Target.Integer.cg_type); END Compile; PROCEDUREFold (ce: CallExpr.T): Expr.T = VAR w0, w1, result: Target.Int; BEGIN IF Plus.GetArgs (ce.args, w0, w1) THEN TWord.And (w0, w1, result); RETURN IntegerExpr.New (T, result); END; RETURN NIL; END Fold; PROCEDUREGetBounds (ce: CallExpr.T; VAR min, max: Target.Int) = VAR min_a, max_a, min_b, max_b : Target.Int; BEGIN Expr.GetBounds (ce.args[0], min_a, max_a); Expr.GetBounds (ce.args[1], min_b, max_b); IF TInt.LT (min_a, TInt.Zero) OR TInt.LT (max_a, TInt.Zero) THEN (* "a" could be 16_ffff... => any bits from "b" can survive *) IF TInt.LT (min_b, TInt.Zero) OR TInt.LT (max_b, TInt.Zero) THEN (* too complicated *) min := Target.Integer.min; max := Target.Integer.max; ELSE (* "b" is non-negative, but "a" could be 16_ffff... *) min := TInt.Zero; (* no bits in common *) max := max_b; END; ELSIF TInt.LT (min_b, TInt.Zero) OR TInt.LT (max_b, TInt.Zero) THEN (* "a" is non-negative, but "b" could be 16_ffff... *) min := TInt.Zero; (* no bits in common *) max := max_a; ELSE (* both a and b are non-negative *) min := TInt.Zero; (* no bits in common *) TWord.And (max_a, max_b, max); END; END GetBounds; PROCEDUREInitialize () = VAR x0 := Formal.NewBuiltin ("x", 0, T); y0 := Formal.NewBuiltin ("y", 1, T); t0 := ProcType.New (T, x0, y0); BEGIN Z := CallExpr.NewMethodList (2, 2, TRUE, TRUE, TRUE, T, NIL, CallExpr.NotAddressable, Check, CallExpr.PrepArgs, Compile, CallExpr.NoLValue, CallExpr.NoLValue, CallExpr.NotBoolean, CallExpr.NotBoolean, Fold, GetBounds, CallExpr.IsNever, (* writable *) CallExpr.IsNever, (* designator *) CallExpr.NotWritable (* noteWriter *)); Procedure.Define ("And", Z, FALSE, t0); formals := ProcType.Formals (t0); END Initialize; BEGIN END WordAnd.