+
+ //
+ // Used when resolved expression has different representations for
+ // expression trees and emit phase
+ //
+ public class ReducedExpression : Expression
+ {
+ class ReducedConstantExpression : Constant
+ {
+ readonly Constant expr;
+ readonly Expression orig_expr;
+
+ public ReducedConstantExpression (Constant expr, Expression orig_expr)
+ : base (expr.Location)
+ {
+ this.expr = expr;
+ this.orig_expr = orig_expr;
+ }
+
+ public override string AsString ()
+ {
+ return expr.AsString ();
+ }
+
+ public override Expression CreateExpressionTree (EmitContext ec)
+ {
+ return orig_expr.CreateExpressionTree (ec);
+ }
+
+ public override object GetValue ()
+ {
+ return expr.GetValue ();
+ }
+
+ public override Constant ConvertExplicitly (bool in_checked_context, Type target_type)
+ {
+ throw new NotImplementedException ();
+ }
+
+ public override Expression DoResolve (EmitContext ec)
+ {
+ eclass = expr.eclass;
+ type = expr.Type;
+ return this;
+ }
+
+ public override Constant Increment ()
+ {
+ throw new NotImplementedException ();
+ }
+
+ public override bool IsDefaultValue {
+ get {
+ return expr.IsDefaultValue;
+ }
+ }
+
+ public override bool IsNegative {
+ get {
+ return expr.IsNegative;
+ }
+ }
+
+ public override void Emit (EmitContext ec)
+ {
+ expr.Emit (ec);
+ }
+ }
+
+ readonly Expression expr, orig_expr;
+
+ private ReducedExpression (Expression expr, Expression orig_expr)
+ {
+ this.expr = expr;
+ this.orig_expr = orig_expr;
+ }
+
+ public static Expression Create (Constant expr, Expression original_expr)
+ {
+ return new ReducedConstantExpression (expr, original_expr);
+ }
+
+ public static Expression Create (Expression expr, Expression original_expr)
+ {
+ Constant c = expr as Constant;
+ if (c != null)
+ return Create (c, original_expr);
+
+ return new ReducedExpression (expr, original_expr);
+ }
+
+ public override Expression CreateExpressionTree (EmitContext ec)
+ {
+ return orig_expr.CreateExpressionTree (ec);
+ }
+
+ public override Expression DoResolve (EmitContext ec)
+ {
+ eclass = expr.eclass;
+ type = expr.Type;
+ return this;
+ }
+
+ public override void Emit (EmitContext ec)
+ {
+ expr.Emit (ec);
+ }
+ }