{
public class NullableType : TypeExpr
{
- Expression underlying;
+ TypeExpr underlying;
- public NullableType (Expression underlying, Location l)
+ public NullableType (TypeExpr underlying, Location l)
{
this.underlying = underlying;
loc = l;
protected override TypeExpr DoResolveAsTypeStep (IResolveContext ec)
{
- TypeArguments args = new TypeArguments (loc);
- args.Add (underlying);
-
if (TypeManager.generic_nullable_type == null) {
TypeManager.generic_nullable_type = TypeManager.CoreLookupType (
"System", "Nullable`1", Kind.Struct, true);
}
- ConstructedType ctype = new ConstructedType (TypeManager.generic_nullable_type, args, loc);
+ TypeArguments args = new TypeArguments (underlying);
+ GenericTypeExpr ctype = new GenericTypeExpr (TypeManager.generic_nullable_type, args, loc);
return ctype.ResolveAsTypeTerminal (ec, false);
}
+
+ public override TypeExpr ResolveAsTypeTerminal (IResolveContext ec, bool silent)
+ {
+ return ResolveAsBaseTerminal (ec, silent);
+ }
}
public sealed class NullableInfo
{
this.expr = expr;
this.loc = expr.Location;
+
+ info = new NullableInfo (expr.Type);
+ type = info.UnderlyingType;
+ eclass = expr.eclass;
+ }
+
+ public static Expression Create (Expression expr)
+ {
+ //
+ // Avoid unwraping and wraping of same type
+ //
+ Wrap wrap = expr as Wrap;
+ if (wrap != null)
+ return wrap.Child;
+
+ return Create (expr, null);
}
public static Unwrap Create (Expression expr, EmitContext ec)
{
- return new Unwrap (expr).Resolve (ec) as Unwrap;
+ return new Unwrap (expr);
}
public override Expression CreateExpressionTree (EmitContext ec)
{
return expr.CreateExpressionTree (ec);
- }
+ }
public override Expression DoResolve (EmitContext ec)
{
- if (expr == null)
- return null;
-
- info = new NullableInfo (expr.Type);
- type = info.UnderlyingType;
- eclass = expr.eclass;
return this;
}
-
+
public override Expression DoResolveLValue (EmitContext ec, Expression right_side)
{
return DoResolve (ec);
- }
+ }
public override void Emit (EmitContext ec)
{
Store (ec);
- AddressOf (ec, AddressOp.LoadStore);
- ec.ig.EmitCall (OpCodes.Call, info.Value, null);
+ Invocation.EmitCall (ec, false, this, info.Value, null, loc);
}
public void EmitCheck (EmitContext ec)
{
Store (ec);
- AddressOf (ec, AddressOp.LoadStore);
- ec.ig.EmitCall (OpCodes.Call, info.HasValue, null);
+ Invocation.EmitCall (ec, false, this, info.HasValue, null, loc);
}
public void EmitGetValueOrDefault (EmitContext ec)
{
Store (ec);
- AddressOf (ec, AddressOp.LoadStore);
- ec.ig.EmitCall (OpCodes.Call, info.GetValueOrDefault, null);
+ Invocation.EmitCall (ec, false, this, info.GetValueOrDefault, null, loc);
}
public override bool Equals (object obj)
eclass = ExprClass.Value;
}
+ public Expression Child {
+ get { return child; }
+ }
+
+ public override Expression CreateExpressionTree (EmitContext ec)
+ {
+ TypeCast child_cast = child as TypeCast;
+ if (child_cast != null) {
+ child.Type = type;
+ return child_cast.CreateExpressionTree (ec);
+ }
+
+ return base.CreateExpressionTree (ec);
+ }
+
public static Expression Create (Expression expr, Type type)
{
//
}
}
- public abstract class Lifted : Expression, IMemoryLocation
+ public class Lifted : Expression, IMemoryLocation
{
- Expression expr, underlying, wrap, null_value;
+ Expression expr, wrap, null_value;
Unwrap unwrap;
- protected Lifted (Expression expr, Location loc)
+ public Lifted (Expression expr, Unwrap unwrap, Type type)
{
this.expr = expr;
- this.loc = loc;
+ this.unwrap = unwrap;
+ this.loc = expr.Location;
+ this.type = type;
+ }
+
+ public Lifted (Expression expr, Expression unwrap, Type type)
+ : this (expr, unwrap as Unwrap, type)
+ {
}
public override Expression CreateExpressionTree (EmitContext ec)
{
- ArrayList args = new ArrayList (2);
- args.Add (new Argument (expr.CreateExpressionTree (ec)));
- args.Add (new Argument (new TypeOf (new TypeExpression (type, loc), loc)));
- return CreateExpressionFactoryCall ("Convert", args);
+ return wrap.CreateExpressionTree (ec);
}
public override Expression DoResolve (EmitContext ec)
{
- expr = expr.Resolve (ec);
- if (expr == null)
+ wrap = Wrap.Create (expr, type);
+ if (wrap == null)
return null;
- unwrap = Unwrap.Create (expr, ec);
+ //
+ // It's null when lifted conversion is transparent
+ //
if (unwrap == null)
- return null;
+ return wrap;
- underlying = ResolveUnderlying (unwrap, ec);
- if (underlying == null)
- return null;
-
- TypeExpr target_type = new NullableType (underlying.Type, loc);
- target_type = target_type.ResolveAsTypeTerminal (ec, false);
- if (target_type == null)
- return null;
+ null_value = LiftedNull.Create (type, loc);
- wrap = Wrap.Create (underlying, target_type.Type);
- if (wrap == null)
- return null;
-
- null_value = LiftedNull.Create (wrap.Type, loc);
-
- type = wrap.Type;
eclass = ExprClass.Value;
return this;
}
- protected abstract Expression ResolveUnderlying (Expression unwrap, EmitContext ec);
-
public override void Emit (EmitContext ec)
{
ILGenerator ig = ec.ig;
}
}
- public class LiftedConversion : Lifted
- {
- public readonly bool IsUser;
- public readonly bool IsExplicit;
- public readonly Type TargetType;
-
- public LiftedConversion (Expression expr, Type target_type, bool is_user,
- bool is_explicit, Location loc)
- : base (expr, loc)
- {
- this.IsUser = is_user;
- this.IsExplicit = is_explicit;
- this.TargetType = target_type;
- }
-
- protected override Expression ResolveUnderlying (Expression unwrap, EmitContext ec)
- {
- Type type = TypeManager.GetTypeArguments (TargetType) [0];
-
- if (IsUser) {
- if (IsExplicit)
- return Convert.ExplicitUserConversion (ec, unwrap, type, loc);
- else
- return Convert.ImplicitUserConversion (ec, unwrap, type, loc);
- } else {
- if (IsExplicit)
- return Convert.ExplicitConversion (ec, unwrap, type, loc);
- else
- return Convert.ImplicitConversion (ec, unwrap, type, loc);
- }
- }
- }
-
public class LiftedUnaryOperator : Unary, IMemoryLocation
{
Unwrap unwrap;
Expression user_operator;
- public LiftedUnaryOperator (Unary.Operator op, Expression expr, Location loc)
- : base (op, expr, loc)
+ public LiftedUnaryOperator (Unary.Operator op, Expression expr)
+ : base (op, expr)
{
}
// Arguments can be lifted for equal operators when the return type is bool and both
// arguments are of same type
//
- if (left is NullLiteral) {
+ if (left_orig.IsNull) {
left = right;
left_null_lifted = true;
type = TypeManager.bool_type;
}
- if (right is NullLiteral) {
+ if (right_orig.IsNull) {
right = left;
right_null_lifted = true;
type = TypeManager.bool_type;
if (user_operator != null)
return false;
+ if (left is UserCast || right is UserCast)
+ return false;
+
Label dissimilar_label = ig.DefineLabel ();
Label end_label = ig.DefineLabel ();
if ((Oper & Operator.ComparisonMask) != 0) {
//
- // Emit true when equality operator both operands are null
- // or inequality operator operands has only one null
+ // Emit true when equality operator both operands are same
+ // or inequality operator operands are not
//
- if ((Oper == Operator.Equality && left_unwrap != null && right_unwrap != null) ||
+ if ((Oper == Operator.Equality && left_unwrap == right_unwrap) ||
(Oper == Operator.Inequality && left_unwrap != right_unwrap))
ig.Emit (OpCodes.Ldc_I4_1);
else
args.Add (new Argument (conversion));
return CreateExpressionFactoryCall ("Coalesce", args);
- }
+ }
- public override Expression DoResolve (EmitContext ec)
+ Expression ConvertExpression (EmitContext ec)
{
- if (type != null)
- return this;
-
- left = left.Resolve (ec);
- right = right.Resolve (ec);
-
- if (left == null || right == null)
+ // TODO: ImplicitConversionExists should take care of this
+ if (left.eclass == ExprClass.MethodGroup)
return null;
- eclass = ExprClass.Value;
- Type ltype = left.Type, rtype = right.Type;
+ Type ltype = left.Type;
//
// If left is a nullable type and an implicit conversion exists from right to underlying type of left,
// the result is underlying type of left
//
- if (TypeManager.IsNullableType (ltype) && left.eclass != ExprClass.MethodGroup) {
+ if (TypeManager.IsNullableType (ltype)) {
unwrap = Unwrap.Create (left, ec);
if (unwrap == null)
return null;
type = left.Type;
right = Convert.ImplicitConversion (ec, right, type, loc);
return this;
- }
- } else if (TypeManager.IsReferenceType (ltype) && right.eclass != ExprClass.MethodGroup) {
+ }
+ } else if (TypeManager.IsReferenceType (ltype)) {
if (Convert.ImplicitConversionExists (ec, right, ltype)) {
//
// Reduce (constant ?? expr) to constant
return this;
}
} else {
- Binary.Error_OperatorCannotBeApplied (left, right, "??", loc);
return null;
}
- if (!Convert.ImplicitConversionExists (ec, unwrap != null ? unwrap : left, rtype)) {
- Binary.Error_OperatorCannotBeApplied (left, right, "??", loc);
+ Type rtype = right.Type;
+ if (!Convert.ImplicitConversionExists (ec, unwrap != null ? unwrap : left, rtype) || right.eclass == ExprClass.MethodGroup)
return null;
- }
//
// Reduce (null ?? right) to right
return this;
}
+ public override Expression DoResolve (EmitContext ec)
+ {
+ if (eclass != ExprClass.Invalid)
+ return this;
+
+ left = left.Resolve (ec);
+ right = right.Resolve (ec);
+
+ if (left == null || right == null)
+ return null;
+
+ eclass = ExprClass.Value;
+
+ Expression e = ConvertExpression (ec);
+ if (e == null) {
+ Binary.Error_OperatorCannotBeApplied (left, right, "??", loc);
+ return null;
+ }
+
+ return e;
+ }
+
public override void Emit (EmitContext ec)
{
ILGenerator ig = ec.ig;
if (unwrap == null)
return null;
- underlying = (UnaryMutator) new UnaryMutator (Mode, unwrap, loc).Resolve (ec);
+ underlying = (UnaryMutator) new UnaryMutator (Mode, unwrap).Resolve (ec);
if (underlying == null)
return null;