/// <summary>
/// Converts the expression for creating a tuple instance into an expression creating a ValueTuple (if short) or nested ValueTuples (if longer).
///
/// For instance, for a long tuple we'll generate:
/// creationExpression(ctor=largestCtor, args=firstArgs+(nested creationExpression for remainder, with smaller ctor and next few args))
/// </summary>
private BoundNode RewriteTupleCreationExpression(BoundTupleExpression node, ImmutableArray <BoundExpression> rewrittenArguments)
{
NamedTypeSymbol underlyingTupleType = node.Type.TupleUnderlyingType;
ArrayBuilder <NamedTypeSymbol> underlyingTupleTypeChain = ArrayBuilder <NamedTypeSymbol> .GetInstance();
TupleTypeSymbol.GetUnderlyingTypeChain(underlyingTupleType, underlyingTupleTypeChain);
try
{
// make a creation expression for the smallest type
NamedTypeSymbol smallestType = underlyingTupleTypeChain.Pop();
ImmutableArray <BoundExpression> smallestCtorArguments = ImmutableArray.Create(rewrittenArguments,
underlyingTupleTypeChain.Count * (TupleTypeSymbol.RestPosition - 1),
smallestType.Arity);
var smallestCtor = (MethodSymbol)TupleTypeSymbol.GetWellKnownMemberInType(smallestType.OriginalDefinition,
TupleTypeSymbol.GetTupleCtor(smallestType.Arity),
_diagnostics,
node.Syntax);
if ((object)smallestCtor == null)
{
return(node);
}
MethodSymbol smallestConstructor = smallestCtor.AsMember(smallestType);
BoundObjectCreationExpression currentCreation = new BoundObjectCreationExpression(node.Syntax, smallestConstructor, smallestCtorArguments);
if (underlyingTupleTypeChain.Count > 0)
{
NamedTypeSymbol tuple8Type = underlyingTupleTypeChain.Peek();
var tuple8Ctor = (MethodSymbol)TupleTypeSymbol.GetWellKnownMemberInType(tuple8Type.OriginalDefinition,
TupleTypeSymbol.GetTupleCtor(TupleTypeSymbol.RestPosition),
_diagnostics,
node.Syntax);
if ((object)tuple8Ctor == null)
{
return(node);
}
// make successively larger creation expressions containing the previous one
do
{
ImmutableArray <BoundExpression> ctorArguments = ImmutableArray.Create(rewrittenArguments,
(underlyingTupleTypeChain.Count - 1) * (TupleTypeSymbol.RestPosition - 1),
TupleTypeSymbol.RestPosition - 1)
.Add(currentCreation);
MethodSymbol constructor = tuple8Ctor.AsMember(underlyingTupleTypeChain.Pop());
currentCreation = new BoundObjectCreationExpression(node.Syntax, constructor, ctorArguments);
}while (underlyingTupleTypeChain.Count > 0);
}
return(currentCreation);
}
finally
{
underlyingTupleTypeChain.Free();
}
}
/// <summary>
/// Converts access to a tuple instance into access into the underlying ValueTuple(s).
///
/// For instance, tuple.Item8
/// produces fieldAccess(field=Item1, receiver=fieldAccess(field=Rest, receiver=ValueTuple for tuple))
/// </summary>
private BoundExpression MakeTupleFieldAccess(
SyntaxNode syntax,
FieldSymbol tupleField,
BoundExpression rewrittenReceiver,
ConstantValue constantValueOpt,
LookupResultKind resultKind)
{
var tupleType = tupleField.ContainingType;
NamedTypeSymbol currentLinkType = tupleType.TupleUnderlyingType;
FieldSymbol underlyingField = tupleField.TupleUnderlyingField;
if ((object)underlyingField == null)
{
// Use-site error must have been reported elsewhere.
return(_factory.BadExpression(tupleField.Type.TypeSymbol));
}
if (rewrittenReceiver.Kind == BoundKind.DefaultExpression)
{
// Optimization: `default((int, string)).Item2` is simply `default(string)`
return(new BoundDefaultExpression(syntax, tupleField.Type.TypeSymbol));
}
if (!TypeSymbol.Equals(underlyingField.ContainingType, currentLinkType, TypeCompareKind.ConsiderEverything2))
{
WellKnownMember wellKnownTupleRest = TupleTypeSymbol.GetTupleTypeMember(TupleTypeSymbol.RestPosition, TupleTypeSymbol.RestPosition);
var tupleRestField = (FieldSymbol)TupleTypeSymbol.GetWellKnownMemberInType(currentLinkType.OriginalDefinition, wellKnownTupleRest, _diagnostics, syntax);
if ((object)tupleRestField == null)
{
// error tolerance for cases when Rest is missing
return(_factory.BadExpression(tupleField.Type.TypeSymbol));
}
// make nested field accesses to Rest
do
{
FieldSymbol nestedFieldSymbol = tupleRestField.AsMember(currentLinkType);
rewrittenReceiver = _factory.Field(rewrittenReceiver, nestedFieldSymbol);
currentLinkType = currentLinkType.TypeArgumentsNoUseSiteDiagnostics[TupleTypeSymbol.RestPosition - 1].TypeSymbol.TupleUnderlyingType;
}while (!TypeSymbol.Equals(underlyingField.ContainingType, currentLinkType, TypeCompareKind.ConsiderEverything2));
}
// make a field access for the most local access
return(_factory.Field(rewrittenReceiver, underlyingField));
}
/// <summary>
/// Converts access to a tuple instance into access into the underlying ValueTuple(s).
///
/// For instance, tuple.Item8
/// produces fieldAccess(field=Item1, receiver=fieldAccess(field=Rest, receiver=ValueTuple for tuple))
/// </summary>
private BoundExpression MakeTupleFieldAccess(
CSharpSyntaxNode syntax,
FieldSymbol tupleField,
BoundExpression rewrittenReceiver,
ConstantValue constantValueOpt,
LookupResultKind resultKind,
TypeSymbol type)
{
var tupleType = tupleField.ContainingType;
NamedTypeSymbol currentLinkType = tupleType.TupleUnderlyingType;
FieldSymbol underlyingField = tupleField.TupleUnderlyingField;
if ((object)underlyingField == null)
{
// Use-site error must have been reported elsewhere.
return(new BoundFieldAccess(syntax, rewrittenReceiver, tupleField, constantValueOpt, resultKind, type, hasErrors: true));
}
if (underlyingField.ContainingType != currentLinkType)
{
WellKnownMember wellKnownTupleRest = TupleTypeSymbol.GetTupleTypeMember(TupleTypeSymbol.RestPosition, TupleTypeSymbol.RestPosition);
var tupleRestField = (FieldSymbol)TupleTypeSymbol.GetWellKnownMemberInType(currentLinkType.OriginalDefinition, wellKnownTupleRest, _diagnostics, syntax);
if ((object)tupleRestField == null)
{
// error tolerance for cases when Rest is missing
return(new BoundFieldAccess(syntax, rewrittenReceiver, tupleField, constantValueOpt, resultKind, type, hasErrors: true));
}
// make nested field accesses to Rest
do
{
FieldSymbol nestedFieldSymbol = tupleRestField.AsMember(currentLinkType);
currentLinkType = currentLinkType.TypeArgumentsNoUseSiteDiagnostics[TupleTypeSymbol.RestPosition - 1].TupleUnderlyingType;
rewrittenReceiver = new BoundFieldAccess(syntax, rewrittenReceiver, nestedFieldSymbol, ConstantValue.NotAvailable, LookupResultKind.Viable, currentLinkType);
}while (underlyingField.ContainingType != currentLinkType);
}
// make a field access for the most local access
return(new BoundFieldAccess(syntax, rewrittenReceiver, underlyingField, constantValueOpt, resultKind, type));
}
private BoundExpression MakeTupleCreationExpression(SyntaxNode syntax, NamedTypeSymbol type, ImmutableArray <BoundExpression> rewrittenArguments)
{
NamedTypeSymbol underlyingTupleType = type.TupleUnderlyingType ?? type;
Debug.Assert(underlyingTupleType.IsTupleCompatible());
ArrayBuilder <NamedTypeSymbol> underlyingTupleTypeChain = ArrayBuilder <NamedTypeSymbol> .GetInstance();
TupleTypeSymbol.GetUnderlyingTypeChain(underlyingTupleType, underlyingTupleTypeChain);
try
{
// make a creation expression for the smallest type
NamedTypeSymbol smallestType = underlyingTupleTypeChain.Pop();
ImmutableArray <BoundExpression> smallestCtorArguments = ImmutableArray.Create(rewrittenArguments,
underlyingTupleTypeChain.Count * (TupleTypeSymbol.RestPosition - 1),
smallestType.Arity);
var smallestCtor = (MethodSymbol)TupleTypeSymbol.GetWellKnownMemberInType(smallestType.OriginalDefinition,
TupleTypeSymbol.GetTupleCtor(smallestType.Arity),
_diagnostics,
syntax);
if ((object)smallestCtor == null)
{
return(_factory.BadExpression(type));
}
MethodSymbol smallestConstructor = smallestCtor.AsMember(smallestType);
BoundObjectCreationExpression currentCreation = new BoundObjectCreationExpression(syntax, smallestConstructor, null, smallestCtorArguments);
if (underlyingTupleTypeChain.Count > 0)
{
NamedTypeSymbol tuple8Type = underlyingTupleTypeChain.Peek();
var tuple8Ctor = (MethodSymbol)TupleTypeSymbol.GetWellKnownMemberInType(tuple8Type.OriginalDefinition,
TupleTypeSymbol.GetTupleCtor(TupleTypeSymbol.RestPosition),
_diagnostics,
syntax);
if ((object)tuple8Ctor == null)
{
return(_factory.BadExpression(type));
}
// make successively larger creation expressions containing the previous one
do
{
ImmutableArray <BoundExpression> ctorArguments = ImmutableArray.Create(rewrittenArguments,
(underlyingTupleTypeChain.Count - 1) * (TupleTypeSymbol.RestPosition - 1),
TupleTypeSymbol.RestPosition - 1)
.Add(currentCreation);
MethodSymbol constructor = tuple8Ctor.AsMember(underlyingTupleTypeChain.Pop());
currentCreation = new BoundObjectCreationExpression(syntax, constructor, null, ctorArguments);
}while (underlyingTupleTypeChain.Count > 0);
}
currentCreation = currentCreation.Update(
currentCreation.Constructor,
currentCreation.Arguments,
currentCreation.ArgumentNamesOpt,
currentCreation.ArgumentRefKindsOpt,
currentCreation.Expanded,
currentCreation.ArgsToParamsOpt,
currentCreation.ConstantValue,
currentCreation.InitializerExpressionOpt,
currentCreation.BinderOpt,
type);
return(currentCreation);
}
finally
{
underlyingTupleTypeChain.Free();
}
}
