if (expr == null)
return null;
- if (expr.Type.IsPointer) {
- Report.Error (244, loc, "\"is\" or \"as\" are not valid on pointer types");
+ if (expr.Type.IsPointer || probe_type_expr.Type.IsPointer) {
+ Report.Error (244, loc, "The `{0}' operator cannot be applied to an operand of pointer type",
+ OperatorName);
return null;
}
+
+ if (expr.Type == TypeManager.anonymous_method_type) {
+ Report.Error (837, loc, "The `{0}' operator cannot be applied to a lambda expression or anonymous method",
+ OperatorName);
+ return null;
+ }
+
return this;
}
+ protected abstract string OperatorName { get; }
+
protected override void CloneTo (CloneContext clonectx, Expression t)
{
Probe target = (Probe) t;
: base (expr, probe_type, l)
{
}
-
- enum Action {
- AlwaysTrue, AlwaysNull, AlwaysFalse, LeaveOnStack, Probe
- }
-
- Action action;
public override void Emit (EmitContext ec)
{
ILGenerator ig = ec.ig;
expr.Emit (ec);
-
- switch (action){
- case Action.AlwaysFalse:
- ig.Emit (OpCodes.Pop);
- IntConstant.EmitInt (ig, 0);
- return;
- case Action.AlwaysTrue:
- ig.Emit (OpCodes.Pop);
- IntConstant.EmitInt (ig, 1);
- return;
- case Action.LeaveOnStack:
- // the `e != null' rule.
- ig.Emit (OpCodes.Ldnull);
- ig.Emit (OpCodes.Ceq);
- ig.Emit (OpCodes.Ldc_I4_0);
- ig.Emit (OpCodes.Ceq);
- return;
- case Action.Probe:
- ig.Emit (OpCodes.Isinst, probe_type_expr.Type);
- ig.Emit (OpCodes.Ldnull);
- ig.Emit (OpCodes.Cgt_Un);
- return;
- }
- throw new Exception ("never reached");
+ ig.Emit (OpCodes.Isinst, probe_type_expr.Type);
+ ig.Emit (OpCodes.Ldnull);
+ ig.Emit (OpCodes.Cgt_Un);
}
public override void EmitBranchable (EmitContext ec, Label target, bool on_true)
{
ILGenerator ig = ec.ig;
- switch (action){
- case Action.AlwaysFalse:
- if (! on_true)
- ig.Emit (OpCodes.Br, target);
-
- return;
- case Action.AlwaysTrue:
- if (on_true)
- ig.Emit (OpCodes.Br, target);
-
- return;
- case Action.LeaveOnStack:
- // the `e != null' rule.
- expr.Emit (ec);
- ig.Emit (on_true ? OpCodes.Brtrue : OpCodes.Brfalse, target);
- return;
- case Action.Probe:
- expr.Emit (ec);
- ig.Emit (OpCodes.Isinst, probe_type_expr.Type);
- ig.Emit (on_true ? OpCodes.Brtrue : OpCodes.Brfalse, target);
- return;
- }
- throw new Exception ("never reached");
+ expr.Emit (ec);
+ ig.Emit (OpCodes.Isinst, probe_type_expr.Type);
+ ig.Emit (on_true ? OpCodes.Brtrue : OpCodes.Brfalse, target);
}
- public override Expression DoResolve (EmitContext ec)
+ Expression CreateConstantResult (bool result)
{
- Expression e = base.DoResolve (ec);
+ if (result)
+ Report.Warning (183, 1, loc, "The given expression is always of the provided (`{0}') type",
+ TypeManager.CSharpName (probe_type_expr.Type));
+ else
+ Report.Warning (184, 1, loc, "The given expression is never of the provided (`{0}') type",
+ TypeManager.CSharpName (probe_type_expr.Type));
+
+ return new BoolConstant (result, loc);
+ }
- if ((e == null) || (expr == null))
+ public override Expression DoResolve (EmitContext ec)
+ {
+ if (base.DoResolve (ec) == null)
return null;
- Type etype = expr.Type;
+ Type d = expr.Type;
+ bool d_is_nullable = false;
+
+ if (expr is Constant) {
+ //
+ // If E is a method group or the null literal, of if the type of E is a reference
+ // type or a nullable type and the value of E is null, the result is false
+ //
+ if (((Constant) expr).GetValue () == null)
+ return CreateConstantResult (false);
+ } else if (TypeManager.IsNullableType (d) && !TypeManager.ContainsGenericParameters (d)) {
+ d = TypeManager.GetTypeArguments (d) [0];
+ d_is_nullable = true;
+ }
+
type = TypeManager.bool_type;
eclass = ExprClass.Value;
+ Type t = probe_type_expr.Type;
+ bool t_is_nullable = false;
+ if (TypeManager.IsNullableType (t) && !TypeManager.ContainsGenericParameters (t)) {
+ t = TypeManager.GetTypeArguments (t) [0];
+ t_is_nullable = true;
+ }
- //
- // First case, if at compile time, there is an implicit conversion
- // then e != null (objects) or true (value types)
- //
- Type probe_type = probe_type_expr.Type;
- e = Convert.ImplicitConversionStandard (ec, expr, probe_type, loc);
- if (e != null){
- expr = e;
- if (etype.IsValueType)
- action = Action.AlwaysTrue;
- else
- action = Action.LeaveOnStack;
-
- Constant c = e as Constant;
- if (c != null && c.Type != etype) {
- action = Action.AlwaysFalse;
- Report.Warning (184, 1, loc, "The given expression is never of the provided (`{0}') type",
- TypeManager.CSharpName (probe_type));
- } else if (etype.IsValueType) {
- Report.Warning (183, 1, loc, "The given expression is always of the provided (`{0}') type",
- TypeManager.CSharpName (probe_type));
+ if (t.IsValueType) {
+ if (d == t) {
+ //
+ // D and T are the same value types but D can be null
+ //
+ if (d_is_nullable && !t_is_nullable)
+ return Nullable.HasValue.Create (expr, ec);
+
+ //
+ // The result is true if D and T are the same value types
+ //
+ return CreateConstantResult (true);
}
- return this;
- }
-
- if (Convert.ExplicitReferenceConversionExists (etype, probe_type)){
- if (TypeManager.IsGenericParameter (etype))
- expr = new BoxedCast (expr, etype);
+
+ if (TypeManager.IsGenericParameter (d))
+ return ResolveGenericParameter (t, d);
//
- // Second case: explicit reference convresion
+ // An unboxing conversion exists
//
- if (expr is NullLiteral)
- action = Action.AlwaysFalse;
- else
- action = Action.Probe;
- } else if (TypeManager.ContainsGenericParameters (etype) ||
- TypeManager.ContainsGenericParameters (probe_type)) {
- expr = new BoxedCast (expr, etype);
- action = Action.Probe;
+ if (Convert.ExplicitReferenceConversionExists (d, t))
+ return this;
} else {
- action = Action.AlwaysFalse;
- if (!(probe_type.IsInterface || expr.Type.IsInterface))
- Report.Warning (184, 1, loc, "The given expression is never of the provided (`{0}') type", TypeManager.CSharpName (probe_type));
+ if (TypeManager.IsGenericParameter (t))
+ return ResolveGenericParameter (d, t);
+
+ if (d.IsValueType) {
+ bool temp;
+ if (Convert.ImplicitBoxingConversionExists (expr, t, out temp))
+ return CreateConstantResult (true);
+ } else {
+ if (TypeManager.IsGenericParameter (d))
+ return ResolveGenericParameter (t, d);
+
+ if (TypeManager.ContainsGenericParameters (d))
+ return this;
+
+ if (Convert.ImplicitReferenceConversionExists (expr, t) ||
+ Convert.ExplicitReferenceConversionExists (d, t)) {
+ return this;
+ }
+ }
}
+ return CreateConstantResult (false);
+ }
+
+ Expression ResolveGenericParameter (Type d, Type t)
+ {
+#if GMCS_SOURCE
+ GenericConstraints constraints = TypeManager.GetTypeParameterConstraints (t);
+ if (constraints != null) {
+ if (constraints.IsReferenceType && d.IsValueType)
+ return CreateConstantResult (false);
+
+ if (constraints.IsValueType && !d.IsValueType)
+ return CreateConstantResult (false);
+ }
+
+ expr = new BoxedCast (expr, d);
return this;
+#else
+ return null;
+#endif
+ }
+
+ protected override string OperatorName {
+ get { return "is"; }
}
}
Error_CannotConvertType (etype, type, loc);
return null;
}
+
+ protected override string OperatorName {
+ get { return "as"; }
+ }
public override bool GetAttributableValue (Type value_type, out object value)
{
target.expr = expr.Clone (clonectx);
}
}
+
+ //
+ // C# 2.0 Default value expression
+ //
+ public class DefaultValueExpression : Expression
+ {
+ Expression expr;
+
+ public DefaultValueExpression (Expression expr, Location loc)
+ {
+ this.expr = expr;
+ this.loc = loc;
+ }
+
+ public override Expression DoResolve (EmitContext ec)
+ {
+ TypeExpr texpr = expr.ResolveAsTypeTerminal (ec, false);
+ if (texpr == null)
+ return null;
+
+ type = texpr.Type;
+
+ if (type == TypeManager.void_type) {
+ Error_VoidInvalidInTheContext (loc);
+ return null;
+ }
+
+ if (TypeManager.IsGenericParameter (type))
+ {
+ GenericConstraints constraints = TypeManager.GetTypeParameterConstraints(type);
+ if (constraints != null && constraints.IsReferenceType)
+ return new NullDefault (new NullLiteral (Location), type);
+ }
+ else
+ {
+ Constant c = New.Constantify(type);
+ if (c != null)
+ return new NullDefault (c, type);
+
+ if (!TypeManager.IsValueType (type))
+ return new NullDefault (new NullLiteral (Location), type);
+ }
+ eclass = ExprClass.Variable;
+ return this;
+ }
+
+ public override void Emit (EmitContext ec)
+ {
+ LocalTemporary temp_storage = new LocalTemporary(type);
+
+ temp_storage.AddressOf(ec, AddressOp.LoadStore);
+ ec.ig.Emit(OpCodes.Initobj, type);
+ temp_storage.Emit(ec);
+ }
+
+ protected override void CloneTo (CloneContext clonectx, Expression t)
+ {
+ DefaultValueExpression target = (DefaultValueExpression) t;
+
+ target.expr = expr.Clone (clonectx);
+ }
+ }
/// <summary>
/// Binary operators
{
if (!IsApplicable_String (ec, left, right, oper))
return false;
+
+ Type l = left.Type;
+ Type r = right.Type;
+ if (OverloadResolve_PredefinedIntegral (ec) ||
+ OverloadResolve_PredefinedFloating (ec)) {
+ Error_OperatorAmbiguous (loc, oper, l, r);
+ }
+
Type t = TypeManager.string_type;
if (Convert.ImplicitConversionExists (ec, left, t))
left = ForceConversion (ec, left, t);
}
//
- // Step 0: String concatenation (because overloading will get this wrong)
+ // String concatenation
+ //
+ // string operator + (string x, string y);
+ // string operator + (string x, object y);
+ // string operator + (object x, string y);
//
- if (oper == Operator.Addition){
- //
- // If any of the arguments is a string, cast to string
+ if (oper == Operator.Addition && !TypeManager.IsDelegateType (l)) {
+ //
+ // Either left or right expression is implicitly convertible to string
//
-
- // Simple constant folding
- if (left is StringConstant && right is StringConstant)
- return new StringConstant (((StringConstant) left).Value + ((StringConstant) right).Value, left.Location);
-
- if (l == TypeManager.string_type || r == TypeManager.string_type) {
-
+ if (OverloadResolve_PredefinedString (ec, oper)) {
if (r == TypeManager.void_type || l == TypeManager.void_type) {
Error_OperatorCannotBeApplied ();
return null;
}
- // try to fold it in on the left
- if (left is StringConcat) {
+ //
+ // Constants folding for strings and nulls
+ //
+ if (left.Type == TypeManager.string_type && right.Type == TypeManager.string_type &&
+ left is Constant && right is Constant) {
+ string lvalue = (string)((Constant) left).GetValue ();
+ string rvalue = (string)((Constant) right).GetValue ();
+ return new StringConstant (lvalue + rvalue, left.Location);
+ }
- //
- // We have to test here for not-null, since we can be doubly-resolved
- // take care of not appending twice
- //
- if (type == null){
- type = TypeManager.string_type;
- ((StringConcat) left).Append (ec, right);
- return left.Resolve (ec);
- } else {
- return left;
- }
+ //
+ // Append to existing string concatenation
+ //
+ if (left is StringConcat) {
+ ((StringConcat) left).Append (ec, right);
+ return left;
}
- // Otherwise, start a new concat expression
+ //
+ // Otherwise, start a new concat expression using converted expression
+ //
return new StringConcat (ec, loc, left, right).Resolve (ec);
}
public bool IsAssigned (EmitContext ec, Location loc)
{
+ // HACK: Variables are not captured in probing mode
+ if (ec.IsInProbingMode)
+ return true;
+
if (!ec.DoFlowAnalysis || !is_out || ec.CurrentBranching.IsAssigned (VariableInfo))
return true;
MethodInfo method = (MethodInfo)mg;
if (method != null) {
type = TypeManager.TypeToCoreType (method.ReturnType);
+
+ // TODO: this is a copy of mg.ResolveMemberAccess method
Expression iexpr = mg.InstanceExpression;
if (method.IsStatic) {
- if (iexpr == null ||
- iexpr is This || iexpr is EmptyExpression ||
- mg.IdenticalTypeName) {
+ if (iexpr == null ||
+ iexpr is This || iexpr is EmptyExpression ||
+ mg.IdenticalTypeName) {
mg.InstanceExpression = null;
} else {
MemberExpr.error176 (loc, mg.GetSignatureForError ());
return null;
}
- } else {
- if (iexpr == null || iexpr is EmptyExpression) {
- SimpleName.Error_ObjectRefRequired (ec, loc, mg.GetSignatureForError ());
- return null;
- }
}
}
"Consider copying `this' to a local variable " +
"outside the anonymous method and using the " +
"local instead.");
- return false;
}
RootScopeInfo host = block.Toplevel.RootScope;
"System.NullReferenceException");
}
+ if (args != null)
+ args.Resolve (ec);
+
Expression member_lookup;
member_lookup = MemberLookup (
ec.ContainerType, expr_type, expr_type, Identifier, loc);
if (ex_method_lookup != null) {
ex_method_lookup.ExtensionExpression = expr_resolved;
- if (args != null)
+ if (args != null) {
+ ex_method_lookup.SetTypeArguments (args);
return ex_method_lookup.ResolveGeneric (ec, args);
+ }
return ex_method_lookup.DoResolve (ec);
}
}
MemberExpr me = (MemberExpr) member_lookup;
- member_lookup = me.ResolveMemberAccess (ec, expr_resolved, loc, original);
- if (member_lookup == null)
- return me;
+ me = me.ResolveMemberAccess (ec, expr_resolved, loc, original);
+ if (me == null)
+ return null;
if (args != null) {
- MethodGroupExpr mg = member_lookup as MethodGroupExpr;
- if (mg == null)
- throw new InternalErrorException ();
-
- return mg.ResolveGeneric (ec, args);
+ me.SetTypeArguments (args);
+ return me.ResolveGeneric (ec, args);
}
if (original != null && !TypeManager.IsValueType (expr_type)) {
- me = member_lookup as MemberExpr;
- if (me != null && me.IsInstance) {
+ if (me.IsInstance) {
LocalVariableReference var = expr_resolved as LocalVariableReference;
if (var != null && !var.VerifyAssigned (ec))
return null;
// check.
if (right_side != null)
- return member_lookup.DoResolveLValue (ec, right_side);
+ return me.DoResolveLValue (ec, right_side);
else
- return member_lookup.DoResolve (ec);
+ return me.DoResolve (ec);
}
public override Expression DoResolve (EmitContext ec)
if (!CommonResolve (ec))
return null;
- Type t = Expr.Type;
- if (t.IsArray)
+ type = Expr.Type;
+ if (type.IsArray)
return (new ArrayAccess (this, loc)).DoResolveLValue (ec, right_side);
- if (t.IsPointer)
- return MakePointerAccess (ec, t);
+ if (type.IsPointer)
+ return MakePointerAccess (ec, type);
- if (t.IsValueType)
- Error_CannotModiftyIntermediateExpressionValue ();
+ if (Expr.eclass != ExprClass.Variable && type.IsValueType)
+ Error_CannotModifyIntermediateExpressionValue (ec);
return (new IndexerAccess (this, loc)).DoResolveLValue (ec, right_side);
}
// if the indexer returns a value type, and we try to set a field in it
if (right_side == EmptyExpression.LValueMemberAccess || right_side == EmptyExpression.LValueMemberOutAccess) {
- Error_CannotModiftyIntermediateExpressionValue ();
+ Error_CannotModifyIntermediateExpressionValue (ec);
}
Expression e = ResolveAccessor (ec, AccessorType.Set);
left = ec.GetThis (loc);
MemberExpr me = (MemberExpr) member_lookup;
-
- Expression e = me.ResolveMemberAccess (ec, left, loc, null);
-
- if (e is PropertyExpr) {
- PropertyExpr pe = (PropertyExpr) e;
- pe.IsBase = true;
- } else if (e is EventExpr) {
- EventExpr ee = (EventExpr) e;
- ee.IsBase = true;
- }
-
- MethodGroupExpr mg = e as MethodGroupExpr;
- if (mg != null)
- mg.IsBase = true;
+ me = me.ResolveMemberAccess (ec, left, loc, null);
+ if (me == null)
+ return null;
+ me.IsBase = true;
if (args != null) {
- if (mg != null)
- return mg.ResolveGeneric (ec, args);
-
- Report.Error (307, loc, "`{0}' cannot be used with type arguments",
- Identifier);
- return null;
+ args.Resolve (ec);
+ me.SetTypeArguments (args);
+ return me.ResolveGeneric (ec, args);
}
- return e;
+ return me;
}
public override void Emit (EmitContext ec)
{
BaseAccess target = (BaseAccess) t;
- target.args = args.Clone ();
+ if (args != null)
+ target.args = args.Clone ();
}
}
loc = l;
}
-#if GMCS_SOURCE
public Expression RemoveNullable ()
{
if (dim.EndsWith ("?")) {
dim = dim.Substring (0, dim.Length - 1);
- if (dim == "")
+ if (dim.Length == 0)
return left;
}
return this;
}
-#endif
protected override TypeExpr DoResolveAsTypeStep (IResolveContext ec)
{
projects / mono.git / blobdiff