private BoundExpression MakeAsOperator(
BoundAsOperator oldNode,
CSharpSyntaxNode syntax,
BoundExpression rewrittenOperand,
BoundTypeExpression rewrittenTargetType,
Conversion conversion,
TypeSymbol rewrittenType)
{
// TODO: Handle dynamic operand type and target type
Debug.Assert(rewrittenTargetType.Type.Equals(rewrittenType));
// target type cannot be a non-nullable value type
Debug.Assert(!rewrittenType.IsValueType || rewrittenType.IsNullableType());
if (!_inExpressionLambda)
{
ConstantValue constantValue = Binder.GetAsOperatorConstantResult(rewrittenOperand.Type, rewrittenType, conversion.Kind, rewrittenOperand.ConstantValue);
if (constantValue != null)
{
Debug.Assert(constantValue.IsNull);
BoundExpression result = rewrittenType.IsNullableType() ? new BoundDefaultOperator(syntax, rewrittenType) : MakeLiteral(syntax, constantValue, rewrittenType);
if (rewrittenOperand.ConstantValue != null)
{
// No need to preserve any side-effects from the operand.
// We also can keep the "constant" notion of the result, which
// enables some optimizations down the road.
return result;
}
return new BoundSequence(
syntax: syntax,
locals: ImmutableArray<LocalSymbol>.Empty,
sideEffects: ImmutableArray.Create<BoundExpression>(rewrittenOperand),
value: result,
type: rewrittenType);
}
if (conversion.IsImplicit)
{
// Operand with bound implicit conversion to target type.
// We don't need a runtime check, generate a conversion for the operand instead.
return MakeConversionNode(syntax, rewrittenOperand, conversion, rewrittenType, @checked: false);
}
}
return oldNode.Update(rewrittenOperand, rewrittenTargetType, conversion, rewrittenType);
}
private BoundExpression MakeAsOperator(
BoundAsOperator oldNode,
CSharpSyntaxNode syntax,
BoundExpression rewrittenOperand,
BoundTypeExpression rewrittenTargetType,
Conversion conversion,
TypeSymbol rewrittenType)
{
// TODO: Handle dynamic operand type and target type
Debug.Assert(rewrittenTargetType.Type.Equals(rewrittenType));
// target type cannot be a non-nullable value type
Debug.Assert(!rewrittenType.IsValueType || rewrittenType.IsNullableType());
if (!inExpressionLambda)
{
ConstantValue constantValue = Binder.GetAsOperatorConstantResult(rewrittenOperand.Type, rewrittenType, conversion.Kind, rewrittenOperand.ConstantValue);
Debug.Assert(constantValue == null || constantValue.IsNull);
if (conversion.IsImplicit)
{
// Operand with bound implicit conversion to target type.
// We don't need a runtime check, generate a conversion for the operand instead.
return MakeConversion(syntax, rewrittenOperand, conversion, rewrittenType, @checked: false, constantValueOpt: constantValue);
}
else if (constantValue != null)
{
return new BoundSequence(
syntax: syntax,
locals: ImmutableArray<LocalSymbol>.Empty,
sideEffects: ImmutableArray.Create<BoundExpression>(rewrittenOperand),
value: MakeLiteral(syntax, constantValue, rewrittenType),
type: rewrittenType);
}
}
return oldNode.Update(rewrittenOperand, rewrittenTargetType, conversion, rewrittenType);
}
private BoundExpression VisitAsOperator(BoundAsOperator node)
{
if (node.Operand.IsLiteralNull() && (object)node.Operand.Type == null)
{
var operand = _bound.Null(_bound.SpecialType(SpecialType.System_Object));
node = node.Update(operand, node.TargetType, node.Conversion, node.Type);
}
return ExprFactory("TypeAs", Visit(node.Operand), _bound.Typeof(node.Type));
}
public override BoundNode VisitAsOperator(BoundAsOperator node)
{
BoundSpillSequence2 ss = null;
var operand = VisitExpression(ref ss, node.Operand);
return UpdateExpression(ss, node.Update(operand, node.TargetType, node.Conversion, node.Type));
}
public override BoundNode VisitAsOperator(BoundAsOperator node)
{
BoundExpression operand = (BoundExpression)this.Visit(node.Operand);
BoundTypeExpression targetType = (BoundTypeExpression)this.Visit(node.TargetType);
TypeSymbol type = this.VisitType(node.Type);
if (operand.Kind != BoundKind.SpillSequence)
{
return node.Update(operand, targetType, node.Conversion, type);
}
var spill = (BoundSpillSequence)operand;
var newAsOperator = node.Update(spill.Value, targetType, node.Conversion, type);
return RewriteSpillSequence(spill, newAsOperator);
}
