public override void Emit(EmitContext ec) { Label is_null_label = ec.DefineLabel(); Label end_label = ec.DefineLabel(); unwrap.EmitCheck(ec); ec.Emit(OpCodes.Brfalse, is_null_label); if (user_operator != null) { user_operator.Emit(ec); } else { EmitOperator(ec, NullableInfo.GetUnderlyingType(type)); } ec.Emit(OpCodes.Newobj, NullableInfo.GetConstructor(type)); ec.Emit(OpCodes.Br_S, end_label); ec.MarkLabel(is_null_label); LiftedNull.Create(type, loc).Emit(ec); ec.MarkLabel(end_label); }
protected override void EmitOperation(EmitContext ec) { Label is_null_label = ec.DefineLabel(); Label end_label = ec.DefineLabel(); LocalTemporary lt = new LocalTemporary(type); // Value is on the stack lt.Store(ec); var call = new CallEmitter(); call.InstanceExpression = lt; call.EmitPredefined(ec, NullableInfo.GetHasValue(expr.Type), null); ec.Emit(OpCodes.Brfalse, is_null_label); call = new CallEmitter(); call.InstanceExpression = lt; call.EmitPredefined(ec, NullableInfo.GetGetValueOrDefault(expr.Type), null); lt.Release(ec); base.EmitOperation(ec); ec.Emit(OpCodes.Newobj, NullableInfo.GetConstructor(type)); ec.Emit(OpCodes.Br_S, end_label); ec.MarkLabel(is_null_label); LiftedNull.Create(type, loc).Emit(ec); ec.MarkLabel(end_label); }
protected override Expression DoResolve(ResolveContext ec) { // // It's null when lifting non-nullable type // if (unwrap == null) { // S -> T? is wrap only if (type.IsNullableType) { return(Wrap.Create(expr, type)); } // S -> T can be simplified return(expr); } // Wrap target for T? if (type.IsNullableType) { expr = Wrap.Create(expr, type); if (expr == null) { return(null); } null_value = LiftedNull.Create(type, loc); } else if (TypeSpec.IsValueType(type)) { null_value = LiftedNull.Create(type, loc); } else { null_value = new NullConstant(type, loc); } eclass = ExprClass.Value; return(this); }
public override void Emit(EmitContext ec) { // // Optimize same expression operation // if (right_unwrap != null && right.Equals(left)) { right_unwrap = left_unwrap; } if (user_operator == null && IsBitwiseBoolean) { EmitBitwiseBoolean(ec); return; } if ((Oper & Operator.EqualityMask) != 0) { EmitEquality(ec); return; } Label is_null_label = ec.DefineLabel(); Label end_label = ec.DefineLabel(); if (left_unwrap != null) { left_unwrap.EmitCheck(ec); ec.Emit(OpCodes.Brfalse, is_null_label); } // // Don't emit HasValue check when left and right expressions are same // if (right_unwrap != null && !left.Equals(right)) { right_unwrap.EmitCheck(ec); ec.Emit(OpCodes.Brfalse, is_null_label); } EmitOperator(ec, left.Type); if (wrap_ctor != null) { ec.Emit(OpCodes.Newobj, wrap_ctor); } ec.Emit(OpCodes.Br_S, end_label); ec.MarkLabel(is_null_label); if ((Oper & Operator.ComparisonMask) != 0) { ec.EmitInt(0); } else { LiftedNull.Create(type, loc).Emit(ec); } ec.MarkLabel(end_label); }
Expression LiftResult(ResolveContext ec, Expression res_expr) { TypeSpec lifted_type; // // Avoid double conversion // if (left_unwrap == null || IsLeftNullLifted || left_unwrap.Type != left.Type || (left_unwrap != null && IsRightNullLifted)) { lifted_type = new NullableType(left.Type, loc).ResolveAsType(ec); if (lifted_type == null) { return(null); } if (left is UserCast || left is EmptyCast || left is OpcodeCast) { left.Type = lifted_type; } else { left = EmptyCast.Create(left, lifted_type); } } if (left != right && (right_unwrap == null || IsRightNullLifted || right_unwrap.Type != right.Type || (right_unwrap != null && IsLeftNullLifted))) { lifted_type = new NullableType(right.Type, loc).ResolveAsType(ec); if (lifted_type == null) { return(null); } var r = right; if (r is ReducedExpression) { r = ((ReducedExpression)r).OriginalExpression; } if (r is UserCast || r is EmptyCast || r is OpcodeCast) { r.Type = lifted_type; } else { right = EmptyCast.Create(right, lifted_type); } } if ((Oper & Operator.ComparisonMask) == 0) { lifted_type = new NullableType(res_expr.Type, loc).ResolveAsType(ec); if (lifted_type == null) { return(null); } wrap_ctor = NullableInfo.GetConstructor(lifted_type); type = res_expr.Type = lifted_type; } if (IsLeftNullLifted) { left = LiftedNull.Create(right.Type, left.Location); // // Special case for bool?, the result depends on both null right side and left side value // if ((Oper == Operator.BitwiseAnd || Oper == Operator.BitwiseOr) && NullableInfo.GetUnderlyingType(type).BuiltinType == BuiltinTypeSpec.Type.Bool) { return(res_expr); } if ((Oper & (Operator.ArithmeticMask | Operator.ShiftMask | Operator.BitwiseMask)) != 0) { return(LiftedNull.CreateFromExpression(ec, res_expr)); } // // Value types and null comparison // if (right_unwrap == null || (Oper & Operator.RelationalMask) != 0) { return(CreateNullConstant(ec, right_orig)); } } if (IsRightNullLifted) { right = LiftedNull.Create(left.Type, right.Location); // // Special case for bool?, the result depends on both null right side and left side value // if ((Oper == Operator.BitwiseAnd || Oper == Operator.BitwiseOr) && NullableInfo.GetUnderlyingType(type).BuiltinType == BuiltinTypeSpec.Type.Bool) { return(res_expr); } if ((Oper & (Operator.ArithmeticMask | Operator.ShiftMask | Operator.BitwiseMask)) != 0) { return(LiftedNull.CreateFromExpression(ec, res_expr)); } // // Value types and null comparison // if (left_unwrap == null || (Oper & Operator.RelationalMask) != 0) { return(CreateNullConstant(ec, left_orig)); } } return(res_expr); }