public SynthesizedIntrinsicOperatorSymbol(TypeSymbol leftType, string name, TypeSymbol rightType, TypeSymbol returnType, bool isCheckedBuiltin)
{
if (leftType.Equals(rightType, TypeCompareKind.IgnoreCustomModifiersAndArraySizesAndLowerBounds))
{
_containingType = leftType;
}
else if (rightType.Equals(returnType, TypeCompareKind.IgnoreCustomModifiersAndArraySizesAndLowerBounds))
{
_containingType = rightType;
}
else
{
Debug.Assert(leftType.Equals(returnType, TypeCompareKind.IgnoreCustomModifiersAndArraySizesAndLowerBounds));
_containingType = leftType;
}
_name = name;
_returnType = returnType;
Debug.Assert((leftType.IsDynamic() || rightType.IsDynamic()) == returnType.IsDynamic());
Debug.Assert(_containingType.IsDynamic() == returnType.IsDynamic());
_parameters = (new ParameterSymbol[] {new SynthesizedOperatorParameterSymbol(this, leftType, 0, "left"),
new SynthesizedOperatorParameterSymbol(this, rightType, 1, "right")}).AsImmutableOrNull();
_isCheckedBuiltin = isCheckedBuiltin;
}
public SynthesizedIntrinsicOperatorSymbol(TypeSymbol leftType, string name, TypeSymbol rightType, TypeSymbol returnType, bool isCheckedBuiltin)
{
if (leftType.Equals(rightType, ignoreCustomModifiers: true))
{
this.containingType = leftType;
}
else if (rightType.Equals(returnType, ignoreCustomModifiers: true))
{
this.containingType = rightType;
}
else
{
Debug.Assert(leftType.Equals(returnType, ignoreCustomModifiers: true));
this.containingType = leftType;
}
this.name = name;
this.returnType = returnType;
Debug.Assert((leftType.IsDynamic() || rightType.IsDynamic()) == returnType.IsDynamic());
Debug.Assert(containingType.IsDynamic() == returnType.IsDynamic());
this.parameters = (new ParameterSymbol[] {new SynthesizedOperatorParameterSymbol(this, leftType, 0, "left"),
new SynthesizedOperatorParameterSymbol(this, rightType, 1, "right")}).AsImmutableOrNull();
this.isCheckedBuiltin = isCheckedBuiltin;
}
private static Symbol GetIntrinsicOperatorSymbol(BinaryOperatorKind op, bool isDynamic, TypeSymbol leftType, TypeSymbol rightType, TypeSymbol returnType, bool isChecked)
{
if (!isDynamic)
{
leftType = leftType.StrippedType();
rightType = rightType.StrippedType();
returnType = returnType.StrippedType();
}
else
{
Debug.Assert(returnType.IsDynamic());
if ((object)leftType == null)
{
Debug.Assert(rightType.IsDynamic());
leftType = rightType;
}
else if ((object)rightType == null)
{
Debug.Assert(leftType.IsDynamic());
rightType = leftType;
}
}
return new SynthesizedIntrinsicOperatorSymbol(leftType,
OperatorFacts.BinaryOperatorNameFromOperatorKind(op),
rightType,
returnType,
isChecked);
}
private TypeSymbol TransformType(TypeSymbol type)
{
Debug.Assert(_index >= 0);
if (!HasFlag ||
PeekFlag() && (type.SpecialType != SpecialType.System_Object && !type.IsDynamic()))
{
// Bail, since flags are invalid.
return null;
}
switch (type.Kind)
{
case SymbolKind.ErrorType:
case SymbolKind.NamedType:
if (type.SpecialType == SpecialType.System_Object)
{
// Replace the given System.Object type with dynamic type if the corresponding dynamicTransformFlag is set to true.
return ConsumeFlag() ? DynamicTypeSymbol.Instance : type;
}
return TransformNamedType((NamedTypeSymbol)type);
case SymbolKind.ArrayType:
return TransformArrayType((ArrayTypeSymbol)type);
case SymbolKind.PointerType:
return TransformPointerType((PointerTypeSymbol)type);
case SymbolKind.DynamicType:
Debug.Assert(!_haveCustomModifierFlags, "This shouldn't happen during decoding.");
return ConsumeFlag()
? type
: _containingAssembly.GetSpecialType(SpecialType.System_Object);
default:
ConsumeFlag();
return HandleCustomModifiers(type.CustomModifierCount()) ? type : null;
}
}
private void TestBinaryIntrinsicSymbol(
BinaryOperatorKind op,
TypeSymbol leftType,
TypeSymbol rightType,
CSharpCompilation compilation,
SemanticModel semanticModel,
ExpressionSyntax node1,
ExpressionSyntax node2,
ExpressionSyntax node3,
ExpressionSyntax node4,
ExpressionSyntax node5,
ExpressionSyntax node6,
ExpressionSyntax node7,
ExpressionSyntax node8
)
{
SymbolInfo info1 = semanticModel.GetSymbolInfo(node1);
HashSet<DiagnosticInfo> useSiteDiagnostics = null;
if (info1.Symbol == null)
{
if (info1.CandidateSymbols.Length == 0)
{
if (leftType.IsDynamic() || rightType.IsDynamic())
{
Assert.True(CandidateReason.LateBound == info1.CandidateReason || CandidateReason.None == info1.CandidateReason);
}
else
{
Assert.Equal(CandidateReason.None, info1.CandidateReason);
}
}
else
{
Assert.Equal(CandidateReason.OverloadResolutionFailure, info1.CandidateReason);
foreach (MethodSymbol s in info1.CandidateSymbols)
{
Assert.Equal(MethodKind.UserDefinedOperator, s.MethodKind);
}
}
}
else
{
Assert.Equal(leftType.IsDynamic() || rightType.IsDynamic() ? CandidateReason.LateBound : CandidateReason.None, info1.CandidateReason);
Assert.Equal(0, info1.CandidateSymbols.Length);
}
var symbol1 = (MethodSymbol)info1.Symbol;
var symbol2 = semanticModel.GetSymbolInfo(node2).Symbol;
var symbol3 = semanticModel.GetSymbolInfo(node3).Symbol;
var symbol4 = semanticModel.GetSymbolInfo(node4).Symbol;
var symbol5 = (MethodSymbol)semanticModel.GetSymbolInfo(node5).Symbol;
var symbol6 = semanticModel.GetSymbolInfo(node6).Symbol;
var symbol7 = semanticModel.GetSymbolInfo(node7).Symbol;
var symbol8 = semanticModel.GetSymbolInfo(node8).Symbol;
Assert.Equal(symbol1, symbol5);
Assert.Equal(symbol2, symbol6);
Assert.Equal(symbol3, symbol7);
Assert.Equal(symbol4, symbol8);
if ((object)symbol1 != null && symbol1.IsImplicitlyDeclared)
{
Assert.NotSame(symbol1, symbol5);
Assert.Equal(symbol1.GetHashCode(), symbol5.GetHashCode());
for (int i = 0; i < 2; i++)
{
Assert.Equal(symbol1.Parameters[i], symbol5.Parameters[i]);
Assert.Equal(symbol1.Parameters[i].GetHashCode(), symbol5.Parameters[i].GetHashCode());
}
Assert.NotEqual(symbol1.Parameters[0], symbol5.Parameters[1]);
}
switch (op)
{
case BinaryOperatorKind.LogicalAnd:
case BinaryOperatorKind.LogicalOr:
Assert.Null(symbol1);
Assert.Null(symbol2);
Assert.Null(symbol3);
Assert.Null(symbol4);
return;
}
BinaryOperatorKind result = OverloadResolution.BinopEasyOut.OpKind(op, leftType, rightType);
BinaryOperatorSignature signature;
bool isDynamic = (leftType.IsDynamic() || rightType.IsDynamic());
if (result == BinaryOperatorKind.Error)
{
if (leftType.IsDynamic() && !rightType.IsPointerType() && !rightType.IsRestrictedType())
{
signature = new BinaryOperatorSignature(op | BinaryOperatorKind.Dynamic, leftType, rightType, leftType);
}
else if (rightType.IsDynamic() && !leftType.IsPointerType() && !leftType.IsRestrictedType())
{
signature = new BinaryOperatorSignature(op | BinaryOperatorKind.Dynamic, leftType, rightType, rightType);
}
else if ((op == BinaryOperatorKind.Equal || op == BinaryOperatorKind.NotEqual) &&
leftType.IsReferenceType && rightType.IsReferenceType &&
(leftType == rightType || compilation.Conversions.ClassifyConversion(leftType, rightType, ref useSiteDiagnostics).IsReference))
{
if (leftType.IsDelegateType() && rightType.IsDelegateType())
{
Assert.Equal(leftType, rightType);
signature = new BinaryOperatorSignature(op | BinaryOperatorKind.Delegate,
leftType, // TODO: this feels like a spec violation
leftType, // TODO: this feels like a spec violation
compilation.GetSpecialType(SpecialType.System_Boolean));
}
else if (leftType.SpecialType == SpecialType.System_Delegate && rightType.SpecialType == SpecialType.System_Delegate)
{
signature = new BinaryOperatorSignature(op | BinaryOperatorKind.Delegate,
compilation.GetSpecialType(SpecialType.System_Delegate), compilation.GetSpecialType(SpecialType.System_Delegate),
compilation.GetSpecialType(SpecialType.System_Boolean));
}
else
{
signature = new BinaryOperatorSignature(op | BinaryOperatorKind.Object, compilation.ObjectType, compilation.ObjectType,
compilation.GetSpecialType(SpecialType.System_Boolean));
}
}
else if (op == BinaryOperatorKind.Addition &&
((leftType.IsStringType() && !rightType.IsPointerType()) || (!leftType.IsPointerType() && rightType.IsStringType())))
{
Assert.False(leftType.IsStringType() && rightType.IsStringType());
if (leftType.IsStringType())
{
signature = new BinaryOperatorSignature(op | BinaryOperatorKind.String, leftType, compilation.ObjectType, leftType);
}
else
{
Assert.True(rightType.IsStringType());
signature = new BinaryOperatorSignature(op | BinaryOperatorKind.String, compilation.ObjectType, rightType, rightType);
}
}
else if (op == BinaryOperatorKind.Addition &&
(((leftType.IsIntegralType() || leftType.IsCharType()) && rightType.IsPointerType()) ||
(leftType.IsPointerType() && (rightType.IsIntegralType() || rightType.IsCharType()))))
{
if (leftType.IsPointerType())
{
signature = new BinaryOperatorSignature(op | BinaryOperatorKind.Pointer, leftType, symbol1.Parameters[1].Type, leftType);
Assert.True(symbol1.Parameters[1].Type.IsIntegralType());
}
else
{
signature = new BinaryOperatorSignature(op | BinaryOperatorKind.Pointer, symbol1.Parameters[0].Type, rightType, rightType);
Assert.True(symbol1.Parameters[0].Type.IsIntegralType());
}
}
else if (op == BinaryOperatorKind.Subtraction &&
(leftType.IsPointerType() && (rightType.IsIntegralType() || rightType.IsCharType())))
{
signature = new BinaryOperatorSignature(op | BinaryOperatorKind.String, leftType, symbol1.Parameters[1].Type, leftType);
Assert.True(symbol1.Parameters[1].Type.IsIntegralType());
}
else if (op == BinaryOperatorKind.Subtraction && leftType.IsPointerType() && leftType == rightType)
{
signature = new BinaryOperatorSignature(op | BinaryOperatorKind.Pointer, leftType, rightType, compilation.GetSpecialType(SpecialType.System_Int64));
}
else if ((op == BinaryOperatorKind.Addition || op == BinaryOperatorKind.Subtraction) &&
leftType.IsEnumType() && (rightType.IsIntegralType() || rightType.IsCharType()) &&
(result = OverloadResolution.BinopEasyOut.OpKind(op, leftType.EnumUnderlyingType(), rightType)) != BinaryOperatorKind.Error &&
(signature = compilation.builtInOperators.GetSignature(result)).RightType == leftType.EnumUnderlyingType())
{
signature = new BinaryOperatorSignature(signature.Kind | BinaryOperatorKind.EnumAndUnderlying, leftType, signature.RightType, leftType);
}
else if ((op == BinaryOperatorKind.Addition || op == BinaryOperatorKind.Subtraction) &&
rightType.IsEnumType() && (leftType.IsIntegralType() || leftType.IsCharType()) &&
(result = OverloadResolution.BinopEasyOut.OpKind(op, leftType, rightType.EnumUnderlyingType())) != BinaryOperatorKind.Error &&
(signature = compilation.builtInOperators.GetSignature(result)).LeftType == rightType.EnumUnderlyingType())
{
signature = new BinaryOperatorSignature(signature.Kind | BinaryOperatorKind.EnumAndUnderlying, signature.LeftType, rightType, rightType);
}
else if (op == BinaryOperatorKind.Subtraction &&
leftType.IsEnumType() && leftType == rightType)
{
signature = new BinaryOperatorSignature(op | BinaryOperatorKind.Enum, leftType, rightType, leftType.EnumUnderlyingType());
}
else if ((op == BinaryOperatorKind.Equal ||
op == BinaryOperatorKind.NotEqual ||
op == BinaryOperatorKind.LessThan ||
op == BinaryOperatorKind.LessThanOrEqual ||
op == BinaryOperatorKind.GreaterThan ||
op == BinaryOperatorKind.GreaterThanOrEqual) &&
leftType.IsEnumType() && leftType == rightType)
{
signature = new BinaryOperatorSignature(op | BinaryOperatorKind.Enum, leftType, rightType, compilation.GetSpecialType(SpecialType.System_Boolean));
}
else if ((op == BinaryOperatorKind.Xor ||
op == BinaryOperatorKind.And ||
op == BinaryOperatorKind.Or) &&
leftType.IsEnumType() && leftType == rightType)
{
signature = new BinaryOperatorSignature(op | BinaryOperatorKind.Enum, leftType, rightType, leftType);
}
else if ((op == BinaryOperatorKind.Addition || op == BinaryOperatorKind.Subtraction) &&
leftType.IsDelegateType() && leftType == rightType)
{
signature = new BinaryOperatorSignature(op | BinaryOperatorKind.Delegate, leftType, leftType, leftType);
}
else if ((op == BinaryOperatorKind.Equal ||
op == BinaryOperatorKind.NotEqual ||
op == BinaryOperatorKind.LessThan ||
op == BinaryOperatorKind.LessThanOrEqual ||
op == BinaryOperatorKind.GreaterThan ||
op == BinaryOperatorKind.GreaterThanOrEqual) &&
leftType.IsPointerType() && rightType.IsPointerType())
{
signature = new BinaryOperatorSignature(op | BinaryOperatorKind.Pointer,
compilation.CreatePointerTypeSymbol(compilation.GetSpecialType(SpecialType.System_Void)),
compilation.CreatePointerTypeSymbol(compilation.GetSpecialType(SpecialType.System_Void)),
compilation.GetSpecialType(SpecialType.System_Boolean));
}
else
{
if ((object)symbol1 != null)
{
Assert.False(symbol1.IsImplicitlyDeclared);
Assert.Equal(MethodKind.UserDefinedOperator, symbol1.MethodKind);
if (leftType.IsValueType && !leftType.IsPointerType())
{
if (rightType.IsValueType && !rightType.IsPointerType())
{
Assert.Same(symbol1, symbol2);
Assert.Same(symbol1, symbol3);
Assert.Same(symbol1, symbol4);
return;
}
else
{
Assert.Null(symbol2);
Assert.Same(symbol1, symbol3);
Assert.Null(symbol4);
return;
}
}
else if (rightType.IsValueType && !rightType.IsPointerType())
{
Assert.Null(symbol2);
Assert.Null(symbol3);
Assert.Same(symbol1, symbol4);
return;
}
else
{
Assert.Null(symbol2);
Assert.Null(symbol3);
Assert.Null(symbol4);
return;
}
}
Assert.Null(symbol1);
Assert.Null(symbol2);
if (!rightType.IsDynamic())
{
Assert.Null(symbol3);
}
if (!leftType.IsDynamic())
{
Assert.Null(symbol4);
}
return;
}
}
else if ((op == BinaryOperatorKind.Equal || op == BinaryOperatorKind.NotEqual) &&
leftType != rightType &&
(!leftType.IsValueType || !rightType.IsValueType ||
leftType.SpecialType == SpecialType.System_Boolean || rightType.SpecialType == SpecialType.System_Boolean ||
(leftType.SpecialType == SpecialType.System_Decimal && (rightType.SpecialType == SpecialType.System_Double || rightType.SpecialType == SpecialType.System_Single)) ||
(rightType.SpecialType == SpecialType.System_Decimal && (leftType.SpecialType == SpecialType.System_Double || leftType.SpecialType == SpecialType.System_Single))) &&
(!leftType.IsReferenceType || !rightType.IsReferenceType ||
!compilation.Conversions.ClassifyConversion(leftType, rightType, ref useSiteDiagnostics).IsReference))
{
Assert.Null(symbol1);
Assert.Null(symbol2);
Assert.Null(symbol3);
Assert.Null(symbol4);
return;
}
else
{
signature = compilation.builtInOperators.GetSignature(result);
}
Assert.NotNull(symbol1);
string containerName = signature.LeftType.ToTestDisplayString();
string leftName = containerName;
string rightName = signature.RightType.ToTestDisplayString();
string returnName = signature.ReturnType.ToTestDisplayString();
if (isDynamic)
{
containerName = compilation.DynamicType.ToTestDisplayString();
}
else if (op == BinaryOperatorKind.Addition || op == BinaryOperatorKind.Subtraction)
{
if (signature.LeftType.IsObjectType() && signature.RightType.IsStringType())
{
containerName = rightName;
}
else if ((leftType.IsEnumType() || leftType.IsPointerType()) && (rightType.IsIntegralType() || rightType.IsCharType()))
{
containerName = leftType.ToTestDisplayString();
leftName = containerName;
returnName = containerName;
}
else if ((rightType.IsEnumType() || rightType.IsPointerType()) && (leftType.IsIntegralType() || leftType.IsCharType()))
{
containerName = rightType.ToTestDisplayString();
rightName = containerName;
returnName = containerName;
}
}
Assert.Equal(isDynamic, signature.ReturnType.IsDynamic());
string expectedSymbol = String.Format("{4} {0}.{2}({1} left, {3} right)",
containerName,
leftName,
OperatorFacts.BinaryOperatorNameFromOperatorKind(op),
rightName,
returnName);
string actualSymbol = symbol1.ToTestDisplayString();
Assert.Equal(expectedSymbol, actualSymbol);
Assert.Equal(MethodKind.BuiltinOperator, symbol1.MethodKind);
Assert.True(symbol1.IsImplicitlyDeclared);
bool isChecked;
switch (op)
{
case BinaryOperatorKind.Multiplication:
case BinaryOperatorKind.Addition:
case BinaryOperatorKind.Subtraction:
case BinaryOperatorKind.Division:
isChecked = isDynamic || symbol1.ContainingSymbol.Kind == SymbolKind.PointerType || symbol1.ContainingType.EnumUnderlyingType().SpecialType.IsIntegralType();
break;
default:
isChecked = isDynamic;
break;
}
Assert.Equal(isChecked, symbol1.IsCheckedBuiltin);
Assert.False(symbol1.IsGenericMethod);
Assert.False(symbol1.IsExtensionMethod);
Assert.False(symbol1.IsExtern);
Assert.False(symbol1.CanBeReferencedByName);
Assert.Null(symbol1.DeclaringCompilation);
Assert.Equal(symbol1.Name, symbol1.MetadataName);
Assert.True(symbol1.ContainingSymbol == symbol1.Parameters[0].Type || symbol1.ContainingSymbol == symbol1.Parameters[1].Type);
int match = 0;
if (symbol1.ContainingSymbol == symbol1.ReturnType)
{
match++;
}
if (symbol1.ContainingSymbol == symbol1.Parameters[0].Type)
{
match++;
}
if (symbol1.ContainingSymbol == symbol1.Parameters[1].Type)
{
match++;
}
Assert.True(match >= 2);
Assert.Equal(0, symbol1.Locations.Length);
Assert.Null(symbol1.GetDocumentationCommentId());
Assert.Equal("", symbol1.GetDocumentationCommentXml());
Assert.True(symbol1.HasSpecialName);
Assert.True(symbol1.IsStatic);
Assert.Equal(Accessibility.Public, symbol1.DeclaredAccessibility);
Assert.False(symbol1.HidesBaseMethodsByName);
Assert.False(symbol1.IsOverride);
Assert.False(symbol1.IsVirtual);
Assert.False(symbol1.IsAbstract);
Assert.False(symbol1.IsSealed);
Assert.Equal(2, symbol1.ParameterCount);
Assert.Equal(0, symbol1.Parameters[0].Ordinal);
Assert.Equal(1, symbol1.Parameters[1].Ordinal);
var otherSymbol = (MethodSymbol)semanticModel.GetSymbolInfo(node1).Symbol;
Assert.Equal(symbol1, otherSymbol);
if (leftType.IsValueType && !leftType.IsPointerType())
{
if (rightType.IsValueType && !rightType.IsPointerType())
{
Assert.Equal(symbol1, symbol2);
Assert.Equal(symbol1, symbol3);
Assert.Equal(symbol1, symbol4);
return;
}
else
{
Assert.Null(symbol2);
if (rightType.IsDynamic())
{
Assert.NotEqual(symbol1, symbol3);
}
else
{
Assert.Equal(rightType.IsPointerType() ? null : symbol1, symbol3);
}
Assert.Null(symbol4);
return;
}
}
else if (rightType.IsValueType && !rightType.IsPointerType())
{
Assert.Null(symbol2);
Assert.Null(symbol3);
if (leftType.IsDynamic())
{
Assert.NotEqual(symbol1, symbol4);
}
else
{
Assert.Equal(leftType.IsPointerType() ? null : symbol1, symbol4);
}
return;
}
Assert.Null(symbol2);
if (rightType.IsDynamic())
{
Assert.NotEqual(symbol1, symbol3);
}
else
{
Assert.Null(symbol3);
}
if (leftType.IsDynamic())
{
Assert.NotEqual(symbol1, symbol4);
}
else
{
Assert.Null(symbol4);
}
}
private TypeSymbol Better(TypeSymbol type1, TypeSymbol type2, ref HashSet<DiagnosticInfo> useSiteDiagnostics)
{
// Anything is better than an error sym.
if (type1.IsErrorType())
{
return type2;
}
if ((object)type2 == null || type2.IsErrorType())
{
return type1;
}
var t1tot2 = _conversions.ClassifyImplicitConversion(type1, type2, ref useSiteDiagnostics).Exists;
var t2tot1 = _conversions.ClassifyImplicitConversion(type2, type1, ref useSiteDiagnostics).Exists;
if (t1tot2 && t2tot1)
{
if (type1.IsDynamic())
{
return type1;
}
if (type2.IsDynamic())
{
return type2;
}
return null;
}
if (t1tot2)
{
return type2;
}
if (t2tot1)
{
return type1;
}
return null;
}
/// <summary>
/// Return the side-effect expression corresponding to an evaluation.
/// </summary>
protected BoundExpression LowerEvaluation(BoundDagEvaluation evaluation)
{
BoundExpression input = _tempAllocator.GetTemp(evaluation.Input);
switch (evaluation)
{
case BoundDagFieldEvaluation f:
{
FieldSymbol field = f.Field;
var outputTemp = new BoundDagTemp(f.Syntax, field.Type, f, index: 0);
BoundExpression output = _tempAllocator.GetTemp(outputTemp);
BoundExpression access = _localRewriter.MakeFieldAccess(f.Syntax, input, field, null, LookupResultKind.Viable, field.Type);
access.WasCompilerGenerated = true;
return(_factory.AssignmentExpression(output, access));
}
case BoundDagPropertyEvaluation p:
{
PropertySymbol property = p.Property;
var outputTemp = new BoundDagTemp(p.Syntax, property.Type, p, index: 0);
BoundExpression output = _tempAllocator.GetTemp(outputTemp);
return(_factory.AssignmentExpression(output, _factory.Property(input, property)));
}
case BoundDagDeconstructEvaluation d:
{
MethodSymbol method = d.DeconstructMethod;
var refKindBuilder = ArrayBuilder <RefKind> .GetInstance();
var argBuilder = ArrayBuilder <BoundExpression> .GetInstance();
BoundExpression receiver;
void addArg(RefKind refKind, BoundExpression expression)
{
refKindBuilder.Add(refKind);
argBuilder.Add(expression);
}
Debug.Assert(method.Name == WellKnownMemberNames.DeconstructMethodName);
int extensionExtra;
if (method.IsStatic)
{
Debug.Assert(method.IsExtensionMethod);
receiver = _factory.Type(method.ContainingType);
addArg(method.ParameterRefKinds[0], input);
extensionExtra = 1;
}
else
{
receiver = input;
extensionExtra = 0;
}
for (int i = extensionExtra; i < method.ParameterCount; i++)
{
ParameterSymbol parameter = method.Parameters[i];
Debug.Assert(parameter.RefKind == RefKind.Out);
var outputTemp = new BoundDagTemp(d.Syntax, parameter.Type, d, i - extensionExtra);
addArg(RefKind.Out, _tempAllocator.GetTemp(outputTemp));
}
return(_factory.Call(receiver, method, refKindBuilder.ToImmutableAndFree(), argBuilder.ToImmutableAndFree()));
}
case BoundDagTypeEvaluation t:
{
TypeSymbol inputType = input.Type;
if (inputType.IsDynamic() || inputType.ContainsTypeParameter())
{
inputType = _factory.SpecialType(SpecialType.System_Object);
}
TypeSymbol type = t.Type;
var outputTemp = new BoundDagTemp(t.Syntax, type, t, index: 0);
BoundExpression output = _tempAllocator.GetTemp(outputTemp);
HashSet <DiagnosticInfo> useSiteDiagnostics = null;
Conversion conversion = _factory.Compilation.Conversions.ClassifyBuiltInConversion(inputType, output.Type, ref useSiteDiagnostics);
_localRewriter._diagnostics.Add(t.Syntax, useSiteDiagnostics);
BoundExpression evaluated;
if (conversion.Exists)
{
if (conversion.Kind == ConversionKind.ExplicitNullable &&
inputType.GetNullableUnderlyingType().Equals(output.Type, TypeCompareKind.AllIgnoreOptions) &&
_localRewriter.TryGetNullableMethod(t.Syntax, inputType, SpecialMember.System_Nullable_T_GetValueOrDefault, out MethodSymbol getValueOrDefault))
{
// As a special case, since the null test has already been done we can use Nullable<T>.GetValueOrDefault
evaluated = _factory.Call(input, getValueOrDefault);
}
else
{
evaluated = _factory.Convert(type, input, conversion);
}
}
else
{
evaluated = _factory.As(input, type);
}
return(_factory.AssignmentExpression(output, evaluated));
}
case BoundDagIndexEvaluation e:
{
// This is an evaluation of an indexed property with a constant int value.
// The input type must be ITuple, and the property must be a property of ITuple.
Debug.Assert(e.Property.ContainingSymbol.Equals(input.Type));
Debug.Assert(e.Property.GetMethod.ParameterCount == 1);
Debug.Assert(e.Property.GetMethod.Parameters[0].Type.SpecialType == SpecialType.System_Int32);
TypeSymbol type = e.Property.GetMethod.ReturnType;
var outputTemp = new BoundDagTemp(e.Syntax, type, e, index: 0);
BoundExpression output = _tempAllocator.GetTemp(outputTemp);
return(_factory.AssignmentExpression(output, _factory.Call(input, e.Property.GetMethod, _factory.Literal(e.Index))));
}
default:
throw ExceptionUtilities.UnexpectedValue(evaluation);
}
}
/// <summary>
/// Lower "using [await] (expression) statement" to a try-finally block.
/// </summary>
private BoundBlock RewriteExpressionUsingStatement(BoundUsingStatement node, BoundBlock tryBlock)
{
Debug.Assert(node.ExpressionOpt != null);
Debug.Assert(node.DeclarationsOpt == null);
// See comments in BuildUsingTryFinally for the details of the lowering to try-finally.
//
// SPEC: A using statement of the form "using (expression) statement; " has the
// SPEC: same three possible expansions [ as "using (ResourceType r = expression) statement; ]
// SPEC: but in this case ResourceType is implicitly the compile-time type of the expression,
// SPEC: and the resource variable is inaccessible to and invisible to the embedded statement.
//
// DELIBERATE SPEC VIOLATION:
//
// The spec quote above implies that the expression must have a type; in fact we allow
// the expression to be null.
//
// If expr is the constant null then we can elide the whole thing and simply generate the statement.
BoundExpression rewrittenExpression = (BoundExpression)Visit(node.ExpressionOpt);
if (rewrittenExpression.ConstantValue == ConstantValue.Null)
{
Debug.Assert(node.Locals.IsEmpty); // TODO: This might not be a valid assumption in presence of semicolon operator.
return(tryBlock);
}
// Otherwise, we lower "using(expression) statement;" as follows:
//
// * If the expression is of type dynamic then we lower as though the user had written
//
// using(IDisposable temp = (IDisposable)expression) statement;
//
// Note that we have to do the conversion early, not in the finally block, because
// if the conversion fails at runtime with an exception then the exception must happen
// before the statement runs.
//
// * Otherwise we lower as though the user had written
//
// using(ResourceType temp = expression) statement;
//
TypeSymbol expressionType = rewrittenExpression.Type;
SyntaxNode expressionSyntax = rewrittenExpression.Syntax;
UsingStatementSyntax usingSyntax = (UsingStatementSyntax)node.Syntax;
BoundAssignmentOperator tempAssignment;
BoundLocal boundTemp;
if ((object)expressionType == null || expressionType.IsDynamic())
{
// IDisposable temp = (IDisposable) expr;
// or
// IAsyncDisposable temp = (IAsyncDisposable) expr;
TypeSymbol iDisposableType = node.AwaitOpt is null?
_compilation.GetSpecialType(SpecialType.System_IDisposable) :
_compilation.GetWellKnownType(WellKnownType.System_IAsyncDisposable);
BoundExpression tempInit = MakeConversionNode(
expressionSyntax,
rewrittenExpression,
Conversion.GetTrivialConversion(node.IDisposableConversion.Kind),
iDisposableType,
@checked: false,
constantValueOpt: rewrittenExpression.ConstantValue);
boundTemp = _factory.StoreToTemp(tempInit, out tempAssignment, kind: SynthesizedLocalKind.Using);
}
else
{
// ResourceType temp = expr;
boundTemp = _factory.StoreToTemp(rewrittenExpression, out tempAssignment, syntaxOpt: usingSyntax, kind: SynthesizedLocalKind.Using);
}
BoundStatement expressionStatement = new BoundExpressionStatement(expressionSyntax, tempAssignment);
if (this.Instrument)
{
expressionStatement = _instrumenter.InstrumentUsingTargetCapture(node, expressionStatement);
}
BoundStatement tryFinally = RewriteUsingStatementTryFinally(usingSyntax, tryBlock, boundTemp, usingSyntax.AwaitKeyword, node.AwaitOpt);
// { ResourceType temp = expr; try { ... } finally { ... } }
return(new BoundBlock(
syntax: usingSyntax,
locals: node.Locals.Add(boundTemp.LocalSymbol),
statements: ImmutableArray.Create <BoundStatement>(expressionStatement, tryFinally)));
}
/// <summary>
/// Check that the pattern type is valid for the operand. Return true if an error was reported.
/// </summary>
private bool CheckValidPatternType(
CSharpSyntaxNode typeSyntax,
BoundExpression operand,
TypeSymbol operandType,
TypeSymbol patternType,
bool patternTypeWasInSource,
bool isVar,
DiagnosticBag diagnostics)
{
Debug.Assert((object)operandType != null);
Debug.Assert((object)patternType != null);
// Because we do not support recursive patterns, we always have an operand
Debug.Assert((object)operand != null);
// Once we support recursive patterns that will be relaxed.
if (operandType.IsErrorType() || patternType.IsErrorType())
{
return(false);
}
else if (patternType.IsNullableType() && !isVar && patternTypeWasInSource)
{
// It is an error to use pattern-matching with a nullable type, because you'll never get null. Use the underlying type.
Error(diagnostics, ErrorCode.ERR_PatternNullableType, typeSyntax, patternType, patternType.GetNullableUnderlyingType());
return(true);
}
else if (patternType.IsStatic)
{
Error(diagnostics, ErrorCode.ERR_VarDeclIsStaticClass, typeSyntax, patternType);
return(true);
}
else if (!isVar)
{
if (patternType.IsDynamic())
{
Error(diagnostics, ErrorCode.ERR_PatternDynamicType, typeSyntax);
return(true);
}
HashSet <DiagnosticInfo> useSiteDiagnostics = null;
Conversion conversion =
operand != null
? this.Conversions.ClassifyConversionFromExpression(operand, patternType, ref useSiteDiagnostics, forCast : true)
: this.Conversions.ClassifyConversionFromType(operandType, patternType, ref useSiteDiagnostics, forCast: true);
diagnostics.Add(typeSyntax, useSiteDiagnostics);
switch (conversion.Kind)
{
case ConversionKind.ExplicitDynamic:
case ConversionKind.ImplicitDynamic:
// Since the input was `dynamic`, which is equivalent to `object`, there must also
// exist some unboxing, identity, or reference conversion as well, making the conversion legal.
case ConversionKind.Boxing:
case ConversionKind.ExplicitNullable:
case ConversionKind.ExplicitReference:
case ConversionKind.Identity:
case ConversionKind.ImplicitReference:
case ConversionKind.Unboxing:
case ConversionKind.ImplicitNullable:
// these are the conversions allowed by a pattern match
break;
case ConversionKind.DefaultOrNullLiteral:
throw ExceptionUtilities.UnexpectedValue(conversion.Kind);
//case ConversionKind.ExplicitNumeric: // we do not perform numeric conversions of the operand
//case ConversionKind.ImplicitConstant:
//case ConversionKind.ImplicitNumeric:
default:
if (operandType.ContainsTypeParameter() || patternType.ContainsTypeParameter())
{
LanguageVersion requiredVersion = MessageID.IDS_FeatureGenericPatternMatching.RequiredVersion();
if (requiredVersion > Compilation.LanguageVersion)
{
Error(diagnostics, ErrorCode.ERR_PatternWrongGenericTypeInVersion, typeSyntax,
operandType, patternType,
Compilation.LanguageVersion.ToDisplayString(),
new CSharpRequiredLanguageVersion(requiredVersion));
return(true);
}
// permit pattern-matching when one of the types is an open type in C# 7.1.
break;
}
else
{
Error(diagnostics, ErrorCode.ERR_PatternWrongType, typeSyntax, operandType, patternType);
return(true);
}
}
}
return(false);
}
/// <summary>
/// Check that the pattern type is valid for the operand. Return true if an error was reported.
/// </summary>
private bool CheckValidPatternType(
CSharpSyntaxNode typeSyntax,
TypeSymbol operandType,
TypeSymbol patternType,
bool patternTypeWasInSource,
bool isVar,
DiagnosticBag diagnostics)
{
Debug.Assert((object)operandType != null);
Debug.Assert((object)patternType != null);
if (operandType.IsErrorType() || patternType.IsErrorType())
{
return(false);
}
else if (patternType.IsNullableType() && !isVar && patternTypeWasInSource)
{
// It is an error to use pattern-matching with a nullable type, because you'll never get null. Use the underlying type.
Error(diagnostics, ErrorCode.ERR_PatternNullableType, typeSyntax, patternType, patternType.GetNullableUnderlyingType());
return(true);
}
else if (patternType.IsStatic)
{
Error(diagnostics, ErrorCode.ERR_VarDeclIsStaticClass, typeSyntax, patternType);
return(true);
}
else if (!isVar)
{
if (patternType.IsDynamic())
{
Error(diagnostics, ErrorCode.ERR_PatternDynamicType, typeSyntax);
return(true);
}
HashSet <DiagnosticInfo> useSiteDiagnostics = null;
var matchPossible = ExpressionOfTypeMatchesPatternType(Conversions, operandType, patternType, ref useSiteDiagnostics, out Conversion conversion, operandConstantValue: null, operandCouldBeNull: true);
diagnostics.Add(typeSyntax, useSiteDiagnostics);
if (matchPossible != false)
{
if (!conversion.Exists && (operandType.ContainsTypeParameter() || patternType.ContainsTypeParameter()))
{
// permit pattern-matching when one of the types is an open type in C# 7.1.
LanguageVersion requiredVersion = MessageID.IDS_FeatureGenericPatternMatching.RequiredVersion();
if (requiredVersion > Compilation.LanguageVersion)
{
Error(diagnostics, ErrorCode.ERR_PatternWrongGenericTypeInVersion, typeSyntax,
operandType, patternType,
Compilation.LanguageVersion.ToDisplayString(),
new CSharpRequiredLanguageVersion(requiredVersion));
return(true);
}
}
}
else
{
Error(diagnostics, ErrorCode.ERR_PatternWrongType, typeSyntax, operandType, patternType);
return(true);
}
}
return(false);
}
/// <summary>
/// Returns the better type amongst the two, with some possible modifications (dynamic/object or tuple names).
/// </summary>
private static TypeSymbol Better(
TypeSymbol type1,
TypeSymbol type2,
ConversionsBase conversions,
out bool hadNullabilityMismatch,
ref HashSet <DiagnosticInfo> useSiteDiagnostics)
{
hadNullabilityMismatch = false;
// Anything is better than an error sym.
if (type1.IsErrorType())
{
return(type2);
}
if ((object)type2 == null || type2.IsErrorType())
{
return(type1);
}
var conversionsWithoutNullability = conversions.WithNullability(false);
var t1tot2 = conversionsWithoutNullability.ClassifyImplicitConversionFromType(type1, type2, ref useSiteDiagnostics).Exists;
var t2tot1 = conversionsWithoutNullability.ClassifyImplicitConversionFromType(type2, type1, ref useSiteDiagnostics).Exists;
if (t1tot2 && t2tot1)
{
if (type1.IsDynamic())
{
return(type1);
}
if (type2.IsDynamic())
{
return(type2);
}
if (type1.Equals(type2, TypeCompareKind.IgnoreDynamicAndTupleNames | TypeCompareKind.IgnoreNullableModifiersForReferenceTypes))
{
return(MethodTypeInferrer.Merge(
TypeSymbolWithAnnotations.Create(type1),
TypeSymbolWithAnnotations.Create(type2),
VarianceKind.Out,
conversions,
out hadNullabilityMismatch).TypeSymbol);
}
return(null);
}
if (t1tot2)
{
return(type2);
}
if (t2tot1)
{
return(type1);
}
return(null);
}
private BoundExpression MakeUnaryOperator(
BoundUnaryOperator oldNode,
UnaryOperatorKind kind,
CSharpSyntaxNode syntax,
MethodSymbol method,
BoundExpression loweredOperand,
TypeSymbol type)
{
if (kind.IsDynamic())
{
Debug.Assert(kind == UnaryOperatorKind.DynamicTrue && type.SpecialType == SpecialType.System_Boolean || type.IsDynamic());
Debug.Assert((object)method == null);
// Logical operators on boxed Boolean constants:
var constant = UnboxConstant(loweredOperand);
if (constant == ConstantValue.True || constant == ConstantValue.False)
{
if (kind == UnaryOperatorKind.DynamicTrue)
{
return(_factory.Literal(constant.BooleanValue));
}
else if (kind == UnaryOperatorKind.DynamicLogicalNegation)
{
return(MakeConversionNode(_factory.Literal(!constant.BooleanValue), type, @checked: false));
}
}
return(_dynamicFactory.MakeDynamicUnaryOperator(kind, loweredOperand, type).ToExpression());
}
else if (kind.IsLifted())
{
if (!_inExpressionLambda)
{
return(LowerLiftedUnaryOperator(kind, syntax, method, loweredOperand, type));
}
}
else if (kind.IsUserDefined())
{
Debug.Assert((object)method != null);
Debug.Assert(type == method.ReturnType);
if (!_inExpressionLambda || kind == UnaryOperatorKind.UserDefinedTrue || kind == UnaryOperatorKind.UserDefinedFalse)
{
// @t-mawind
// As usual, concept accesses need to be rewritten down to their
// default() form.
// Is this correct? It's mostly a copy over from the binary case,
// but the unary case is different enough to make me nervous.
if (method is SynthesizedWitnessMethodSymbol)
{
return(BoundCall.Synthesized(syntax, SynthesizeWitnessInvocationReceiver(syntax, ((SynthesizedWitnessMethodSymbol)method).Parent), method, loweredOperand));
}
return(BoundCall.Synthesized(syntax, null, method, loweredOperand));
}
}
else if (kind.Operator() == UnaryOperatorKind.UnaryPlus)
{
// We do not call the operator even for decimal; we simply optimize it away entirely.
return(loweredOperand);
}
if (kind == UnaryOperatorKind.EnumBitwiseComplement)
{
var underlyingType = loweredOperand.Type.GetEnumUnderlyingType();
var upconvertSpecialType = Binder.GetEnumPromotedType(underlyingType.SpecialType);
var upconvertType = upconvertSpecialType == underlyingType.SpecialType ?
underlyingType :
_compilation.GetSpecialType(upconvertSpecialType);
var newOperand = MakeConversionNode(loweredOperand, upconvertType, false);
UnaryOperatorKind newKind = kind.Operator().WithType(upconvertSpecialType);
var newNode = (oldNode != null) ?
oldNode.Update(
newKind,
newOperand,
oldNode.ConstantValueOpt,
method,
newOperand.ResultKind,
upconvertType) :
new BoundUnaryOperator(
syntax,
newKind,
newOperand,
null,
method,
LookupResultKind.Viable,
upconvertType);
return(MakeConversionNode(newNode.Syntax, newNode, Conversion.ExplicitEnumeration, type, @checked: false));
}
if (kind == UnaryOperatorKind.DecimalUnaryMinus)
{
method = (MethodSymbol)_compilation.Assembly.GetSpecialTypeMember(SpecialMember.System_Decimal__op_UnaryNegation);
if (!_inExpressionLambda)
{
return(BoundCall.Synthesized(syntax, null, method, loweredOperand));
}
}
return((oldNode != null) ?
oldNode.Update(kind, loweredOperand, oldNode.ConstantValueOpt, method, oldNode.ResultKind, type) :
new BoundUnaryOperator(syntax, kind, loweredOperand, null, method, LookupResultKind.Viable, type));
}
internal static BoundStatement BindUsingStatementOrDeclarationFromParts(SyntaxNode syntax, SyntaxToken usingKeyword, SyntaxToken awaitKeyword, Binder originalBinder, UsingStatementBinder usingBinderOpt, DiagnosticBag diagnostics)
{
bool isUsingDeclaration = syntax.Kind() == SyntaxKind.LocalDeclarationStatement;
bool isExpression = !isUsingDeclaration && syntax.Kind() != SyntaxKind.VariableDeclaration;
bool hasAwait = awaitKeyword != default;
Debug.Assert(isUsingDeclaration || usingBinderOpt != null);
TypeSymbol disposableInterface = getDisposableInterface(hasAwait);
Debug.Assert((object)disposableInterface != null);
bool hasErrors = ReportUseSiteDiagnostics(disposableInterface, diagnostics, hasAwait ? awaitKeyword : usingKeyword);
Conversion iDisposableConversion;
ImmutableArray <BoundLocalDeclaration> declarationsOpt = default;
BoundMultipleLocalDeclarations multipleDeclarationsOpt = null;
BoundExpression expressionOpt = null;
TypeSymbol declarationTypeOpt = null;
MethodSymbol disposeMethodOpt;
TypeSymbol awaitableTypeOpt;
if (isExpression)
{
expressionOpt = usingBinderOpt.BindTargetExpression(diagnostics, originalBinder);
hasErrors |= !populateDisposableConversionOrDisposeMethod(fromExpression: true, out iDisposableConversion, out disposeMethodOpt, out awaitableTypeOpt);
}
else
{
VariableDeclarationSyntax declarationSyntax = isUsingDeclaration ? ((LocalDeclarationStatementSyntax)syntax).Declaration : (VariableDeclarationSyntax)syntax;
originalBinder.BindForOrUsingOrFixedDeclarations(declarationSyntax, LocalDeclarationKind.UsingVariable, diagnostics, out declarationsOpt);
Debug.Assert(!declarationsOpt.IsEmpty);
multipleDeclarationsOpt = new BoundMultipleLocalDeclarations(declarationSyntax, declarationsOpt);
declarationTypeOpt = declarationsOpt[0].DeclaredTypeOpt.Type;
if (declarationTypeOpt.IsDynamic())
{
iDisposableConversion = Conversion.ImplicitDynamic;
disposeMethodOpt = null;
awaitableTypeOpt = null;
}
else
{
hasErrors |= !populateDisposableConversionOrDisposeMethod(fromExpression: false, out iDisposableConversion, out disposeMethodOpt, out awaitableTypeOpt);
}
}
BoundAwaitableInfo awaitOpt = null;
if (hasAwait)
{
// even if we don't have a proper value to await, we'll still report bad usages of `await`
originalBinder.ReportBadAwaitDiagnostics(syntax, awaitKeyword.GetLocation(), diagnostics, ref hasErrors);
if (awaitableTypeOpt is null)
{
awaitOpt = new BoundAwaitableInfo(syntax, awaitableInstancePlaceholder: null, isDynamic: true, getAwaiter: null, isCompleted: null, getResult: null)
{
WasCompilerGenerated = true
};
}
else
{
hasErrors |= ReportUseSiteDiagnostics(awaitableTypeOpt, diagnostics, awaitKeyword);
var placeholder = new BoundAwaitableValuePlaceholder(syntax, valEscape: originalBinder.LocalScopeDepth, awaitableTypeOpt).MakeCompilerGenerated();
awaitOpt = originalBinder.BindAwaitInfo(placeholder, syntax, diagnostics, ref hasErrors);
}
}
// This is not awesome, but its factored.
// In the future it might be better to have a separate shared type that we add the info to, and have the callers create the appropriate bound nodes from it
if (isUsingDeclaration)
{
return(new BoundUsingLocalDeclarations(syntax, disposeMethodOpt, iDisposableConversion, awaitOpt, declarationsOpt, hasErrors));
}
else
{
BoundStatement boundBody = originalBinder.BindPossibleEmbeddedStatement(usingBinderOpt._syntax.Statement, diagnostics);
return(new BoundUsingStatement(
usingBinderOpt._syntax,
usingBinderOpt.Locals,
multipleDeclarationsOpt,
expressionOpt,
iDisposableConversion,
boundBody,
awaitOpt,
disposeMethodOpt,
hasErrors));
}
bool populateDisposableConversionOrDisposeMethod(bool fromExpression, out Conversion iDisposableConversion, out MethodSymbol disposeMethodOpt, out TypeSymbol awaitableTypeOpt)
{
HashSet <DiagnosticInfo> useSiteDiagnostics = null;
iDisposableConversion = classifyConversion(fromExpression, disposableInterface, ref useSiteDiagnostics);
disposeMethodOpt = null;
awaitableTypeOpt = null;
diagnostics.Add(syntax, useSiteDiagnostics);
if (iDisposableConversion.IsImplicit)
{
if (hasAwait)
{
awaitableTypeOpt = originalBinder.Compilation.GetWellKnownType(WellKnownType.System_Threading_Tasks_ValueTask);
}
return(true);
}
TypeSymbol type = fromExpression ? expressionOpt.Type : declarationTypeOpt;
// If this is a ref struct, or we're in a valid asynchronous using, try binding via pattern.
// We won't need to try and bind a second time if it fails, as async dispose can't be pattern based (ref structs are not allowed in async methods)
if (type is object && (type.IsRefLikeType || hasAwait))
{
BoundExpression receiver = fromExpression
? expressionOpt
: new BoundLocal(syntax, declarationsOpt[0].LocalSymbol, null, type)
{
WasCompilerGenerated = true
};
DiagnosticBag patternDiagnostics = originalBinder.Compilation.IsFeatureEnabled(MessageID.IDS_FeatureUsingDeclarations)
? diagnostics
: new DiagnosticBag();
disposeMethodOpt = originalBinder.TryFindDisposePatternMethod(receiver, syntax, hasAwait, patternDiagnostics);
if (disposeMethodOpt is object)
{
MessageID.IDS_FeatureUsingDeclarations.CheckFeatureAvailability(diagnostics, originalBinder.Compilation, syntax.Location);
if (hasAwait)
{
awaitableTypeOpt = disposeMethodOpt.ReturnType;
}
return(true);
}
}
if (type is null || !type.IsErrorType())
{
// Retry with a different assumption about whether the `using` is async
TypeSymbol alternateInterface = getDisposableInterface(!hasAwait);
HashSet <DiagnosticInfo> ignored = null;
Conversion alternateConversion = classifyConversion(fromExpression, alternateInterface, ref ignored);
bool wrongAsync = alternateConversion.IsImplicit;
ErrorCode errorCode = wrongAsync
? (hasAwait ? ErrorCode.ERR_NoConvToIAsyncDispWrongAsync : ErrorCode.ERR_NoConvToIDispWrongAsync)
: (hasAwait ? ErrorCode.ERR_NoConvToIAsyncDisp : ErrorCode.ERR_NoConvToIDisp);
Error(diagnostics, errorCode, syntax, declarationTypeOpt ?? expressionOpt.Display);
}
return(false);
}
Conversion classifyConversion(bool fromExpression, TypeSymbol targetInterface, ref HashSet <DiagnosticInfo> diag)
{
return(fromExpression ?
originalBinder.Conversions.ClassifyImplicitConversionFromExpression(expressionOpt, targetInterface, ref diag) :
originalBinder.Conversions.ClassifyImplicitConversionFromType(declarationTypeOpt, targetInterface, ref diag));
}
TypeSymbol getDisposableInterface(bool isAsync)
{
return(isAsync
? originalBinder.Compilation.GetWellKnownType(WellKnownType.System_IAsyncDisposable)
: originalBinder.Compilation.GetSpecialType(SpecialType.System_IDisposable));
}
}
private BoundExpression GetDefaultParameterValue(CSharpSyntaxNode syntax, ParameterSymbol parameter)
{
TypeSymbol parameterType = parameter.Type;
ConstantValue defaultConstantValue = parameter.ExplicitDefaultConstantValue;
BoundExpression defaultValue;
SourceLocation callerSourceLocation;
if (parameter.IsCallerLineNumber && ((callerSourceLocation = GetCallerLocation(syntax)) != null))
{
int line = callerSourceLocation.SourceTree.GetDisplayLineNumber(callerSourceLocation.SourceSpan);
BoundExpression lineLiteral = MakeLiteral(syntax, ConstantValue.Create(line), compilation.GetSpecialType(SpecialType.System_Int32));
if (parameterType.IsNullableType())
{
defaultValue = MakeConversion(lineLiteral, parameterType.GetNullableUnderlyingType(), false);
// wrap it in a nullable ctor.
defaultValue = new BoundObjectCreationExpression(
syntax,
GetNullableMethod(syntax, parameterType, SpecialMember.System_Nullable_T__ctor),
defaultValue);
}
else
{
defaultValue = MakeConversion(lineLiteral, parameterType, false);
}
}
else if (parameter.IsCallerFilePath && ((callerSourceLocation = GetCallerLocation(syntax)) != null))
{
string path = callerSourceLocation.SourceTree.GetDisplayPath(callerSourceLocation.SourceSpan, compilation.Options.SourceReferenceResolver);
BoundExpression memberNameLiteral = MakeLiteral(syntax, ConstantValue.Create(path), compilation.GetSpecialType(SpecialType.System_String));
defaultValue = MakeConversion(memberNameLiteral, parameterType, false);
}
else if (parameter.IsCallerMemberName && ((callerSourceLocation = GetCallerLocation(syntax)) != null))
{
string memberName = this.factory.TopLevelMethod.GetMemberCallerName();
BoundExpression memberNameLiteral = MakeLiteral(syntax, ConstantValue.Create(memberName), compilation.GetSpecialType(SpecialType.System_String));
defaultValue = MakeConversion(memberNameLiteral, parameterType, false);
}
else if (defaultConstantValue == ConstantValue.NotAvailable)
{
// There is no constant value given for the parameter in source/metadata.
if (parameterType.IsDynamic() || parameterType.SpecialType == SpecialType.System_Object)
{
// We have something like M([Optional] object x). We have special handling for such situations.
defaultValue = GetDefaultParameterSpecial(syntax, parameter);
}
else
{
// The argument to M([Optional] int x) becomes default(int)
defaultValue = new BoundDefaultOperator(syntax, parameterType);
}
}
else if (defaultConstantValue.IsNull && parameterType.IsValueType)
{
// We have something like M(int? x = null) or M(S x = default(S)),
// so replace the argument with default(int?).
defaultValue = new BoundDefaultOperator(syntax, parameterType);
}
else if (parameterType.IsNullableType())
{
// We have something like M(double? x = 1.23), so replace the argument
// with new double?(1.23).
TypeSymbol constantType = compilation.GetSpecialType(defaultConstantValue.SpecialType);
defaultValue = MakeLiteral(syntax, defaultConstantValue, constantType);
// The parameter's underlying type might not match the constant type. For example, we might have
// a default value of 5 (an integer) but a parameter type of decimal?.
defaultValue = MakeConversion(defaultValue, parameterType.GetNullableUnderlyingType(), @checked: false, acceptFailingConversion: true);
// Finally, wrap it in a nullable ctor.
defaultValue = new BoundObjectCreationExpression(
syntax,
GetNullableMethod(syntax, parameterType, SpecialMember.System_Nullable_T__ctor),
defaultValue);
}
else if (defaultConstantValue.IsNull || defaultConstantValue.IsBad)
{
defaultValue = MakeLiteral(syntax, defaultConstantValue, parameterType);
}
else
{
// We have something like M(double = 1.23), so replace the argument with 1.23.
TypeSymbol constantType = compilation.GetSpecialType(defaultConstantValue.SpecialType);
defaultValue = MakeLiteral(syntax, defaultConstantValue, constantType);
// The parameter type might not match the constant type.
defaultValue = MakeConversion(defaultValue, parameterType, @checked: false, acceptFailingConversion: true);
}
return(defaultValue);
}
/// <summary>
/// Lower "using (expression) statement" to a try-finally block.
/// </summary>
private BoundBlock RewriteExpressionUsingStatement(BoundUsingStatement node, BoundBlock tryBlock)
{
Debug.Assert(node.ExpressionOpt != null);
Debug.Assert(node.DeclarationsOpt == null);
// See comments in BuildUsingTryFinally for the details of the lowering to try-finally.
//
// SPEC: A using statement of the form "using (expression) statement; " has the
// SPEC: same three possible expansions [ as "using (ResourceType r = expression) statement; ]
// SPEC: but in this case ResourceType is implicitly the compile-time type of the expression,
// SPEC: and the resource variable is inaccessible to and invisible to the embedded statement.
//
// DELIBERATE SPEC VIOLATION:
//
// The spec quote above implies that the expression must have a type; in fact we allow
// the expression to be null.
//
// If expr is the constant null then we can elide the whole thing and simply generate the statement.
BoundExpression rewrittenExpression = (BoundExpression)Visit(node.ExpressionOpt);
if (rewrittenExpression.ConstantValue == ConstantValue.Null)
{
return(tryBlock);
}
// Otherwise, we lower "using(expression) statement;" as follows:
//
// * If the expression is of type dynamic then we lower as though the user had written
//
// using(IDisposable temp = (IDisposable)expression) statement;
//
// Note that we have to do the conversion early, not in the finally block, because
// if the conversion fails at runtime with an exception then the exception must happen
// before the statement runs.
//
// * Otherwise we lower as though the user had written
//
// using(ResourceType temp = expression) statement;
//
TypeSymbol expressionType = rewrittenExpression.Type;
CSharpSyntaxNode expressionSyntax = rewrittenExpression.Syntax;
UsingStatementSyntax usingSyntax = (UsingStatementSyntax)node.Syntax;
BoundAssignmentOperator tempAssignment;
BoundLocal boundTemp;
if ((object)expressionType == null || expressionType.IsDynamic())
{
// IDisposable temp = (IDisposable) expr;
BoundExpression tempInit = MakeConversion(
expressionSyntax,
rewrittenExpression,
node.IDisposableConversion.Kind,
this.compilation.GetSpecialType(SpecialType.System_IDisposable),
@checked: false,
constantValueOpt: rewrittenExpression.ConstantValue);
boundTemp = this.factory.StoreToTemp(tempInit, out tempAssignment);
}
else
{
// ResourceType temp = expr;
boundTemp = this.factory.StoreToTemp(rewrittenExpression, tempKind: TempKind.Using, store: out tempAssignment);
}
BoundStatement expressionStatement = new BoundExpressionStatement(expressionSyntax, tempAssignment);
if (this.generateDebugInfo)
{
// NOTE: unlike in the assignment case, the sequence point is on the using keyword, not the expression.
expressionStatement = new BoundSequencePointWithSpan(usingSyntax, expressionStatement, usingSyntax.UsingKeyword.Span);
}
BoundStatement tryFinally = RewriteUsingStatementTryFinally(usingSyntax, tryBlock, boundTemp);
// { ResourceType temp = expr; try { ... } finally { ... } }
return(new BoundBlock(
syntax: usingSyntax,
localsOpt: ImmutableArray.Create <LocalSymbol>(boundTemp.LocalSymbol),
statements: ImmutableArray.Create <BoundStatement>(expressionStatement, tryFinally)));
}
/// <summary>
/// If the extension method is applicable based on the "this" argument type, return
/// the method constructed with the inferred type arguments. If the method is not an
/// unconstructed generic method, type inference is skipped. If the method is not
/// applicable, or if constraints when inferring type parameters from the "this" type
/// are not satisfied, the return value is null.
/// </summary>
public static MethodSymbol InferExtensionMethodTypeArguments(this MethodSymbol method, TypeSymbol thisType, Compilation compilation, ref HashSet<DiagnosticInfo> useSiteDiagnostics)
{
Debug.Assert(method.IsExtensionMethod);
Debug.Assert((object)thisType != null);
if (!method.IsGenericMethod || method != method.ConstructedFrom)
{
return method;
}
// We never resolve extension methods on a dynamic receiver.
if (thisType.IsDynamic())
{
return null;
}
var containingAssembly = method.ContainingAssembly;
var errorNamespace = containingAssembly.GlobalNamespace;
var conversions = new TypeConversions(containingAssembly.CorLibrary);
// There is absolutely no plausible syntax/tree that we could use for these
// synthesized literals. We could be speculatively binding a call to a PE method.
var syntaxTree = CSharpSyntaxTree.Dummy;
var syntax = (CSharpSyntaxNode)syntaxTree.GetRoot();
// Create an argument value for the "this" argument of specific type,
// and pass the same bad argument value for all other arguments.
var thisArgumentValue = new BoundLiteral(syntax, ConstantValue.Bad, thisType) { WasCompilerGenerated = true };
var otherArgumentType = new ExtendedErrorTypeSymbol(errorNamespace, name: string.Empty, arity: 0, errorInfo: null, unreported: false);
var otherArgumentValue = new BoundLiteral(syntax, ConstantValue.Bad, otherArgumentType) { WasCompilerGenerated = true };
var paramCount = method.ParameterCount;
var arguments = new BoundExpression[paramCount];
var argumentTypes = new TypeSymbol[paramCount];
for (int i = 0; i < paramCount; i++)
{
var argument = (i == 0) ? thisArgumentValue : otherArgumentValue;
arguments[i] = argument;
argumentTypes[i] = argument.Type;
}
var typeArgs = MethodTypeInferrer.InferTypeArgumentsFromFirstArgument(
conversions,
method,
argumentTypes.AsImmutableOrNull(),
arguments.AsImmutableOrNull(),
ref useSiteDiagnostics);
if (typeArgs.IsDefault)
{
return null;
}
int firstNullInTypeArgs = -1;
// For the purpose of constraint checks we use error type symbol in place of type arguments that we couldn't infer from the first argument.
// This prevents constraint checking from failing for corresponding type parameters.
var typeArgsForConstraintsCheck = typeArgs;
for (int i = 0; i < typeArgsForConstraintsCheck.Length; i++)
{
if ((object)typeArgsForConstraintsCheck[i] == null)
{
firstNullInTypeArgs = i;
var builder = ArrayBuilder<TypeSymbol>.GetInstance();
builder.AddRange(typeArgs, firstNullInTypeArgs);
for (; i < typeArgsForConstraintsCheck.Length; i++)
{
builder.Add(typeArgsForConstraintsCheck[i] ?? ErrorTypeSymbol.UnknownResultType);
}
typeArgsForConstraintsCheck = builder.ToImmutableAndFree();
break;
}
}
// Check constraints.
var diagnosticsBuilder = ArrayBuilder<TypeParameterDiagnosticInfo>.GetInstance();
var typeParams = method.TypeParameters;
var substitution = new TypeMap(typeParams, typeArgsForConstraintsCheck.SelectAsArray(TypeMap.TypeSymbolAsTypeWithModifiers));
ArrayBuilder<TypeParameterDiagnosticInfo> useSiteDiagnosticsBuilder = null;
var success = method.CheckConstraints(conversions, substitution, typeParams, typeArgsForConstraintsCheck, compilation, diagnosticsBuilder, ref useSiteDiagnosticsBuilder);
diagnosticsBuilder.Free();
if (useSiteDiagnosticsBuilder != null && useSiteDiagnosticsBuilder.Count > 0)
{
if (useSiteDiagnostics == null)
{
useSiteDiagnostics = new HashSet<DiagnosticInfo>();
}
foreach (var diag in useSiteDiagnosticsBuilder)
{
useSiteDiagnostics.Add(diag.DiagnosticInfo);
}
}
if (!success)
{
return null;
}
// For the purpose of construction we use original type parameters in place of type arguments that we couldn't infer from the first argument.
var typeArgsForConstruct = typeArgs;
if (firstNullInTypeArgs != -1)
{
var builder = ArrayBuilder<TypeSymbol>.GetInstance();
builder.AddRange(typeArgs, firstNullInTypeArgs);
for (int i = firstNullInTypeArgs; i < typeArgsForConstruct.Length; i++)
{
builder.Add(typeArgsForConstruct[i] ?? typeParams[i]);
}
typeArgsForConstruct = builder.ToImmutableAndFree();
}
return method.Construct(typeArgsForConstruct);
}
private bool IsCheckedConversion(TypeSymbol source, TypeSymbol target)
{
Debug.Assert((object)target != null);
if ((object)source == null || !CheckOverflowAtRuntime)
{
return false;
}
if (source.IsDynamic())
{
return true;
}
SpecialType sourceST = source.StrippedType().EnumUnderlyingType().SpecialType;
SpecialType targetST = target.StrippedType().EnumUnderlyingType().SpecialType;
// integral to double or float is never checked, but float/double to integral
// may be checked.
bool sourceIsNumeric = SpecialType.System_Char <= sourceST && sourceST <= SpecialType.System_Double;
bool targetIsNumeric = SpecialType.System_Char <= targetST && targetST <= SpecialType.System_UInt64;
return
sourceIsNumeric && (targetIsNumeric || target.IsPointerType()) ||
targetIsNumeric && source.IsPointerType();
}
protected BoundExpression LowerEvaluation(BoundDagEvaluation evaluation)
{
BoundExpression input = _tempAllocator.GetTemp(evaluation.Input);
switch (evaluation)
{
case BoundDagFieldEvaluation f:
{
FieldSymbol field = f.Field;
var outputTemp = new BoundDagTemp(f.Syntax, field.Type, f);
BoundExpression output = _tempAllocator.GetTemp(outputTemp);
BoundExpression access = _localRewriter.MakeFieldAccess(f.Syntax, input, field, null, LookupResultKind.Viable, field.Type);
access.WasCompilerGenerated = true;
return(_factory.AssignmentExpression(output, access));
}
case BoundDagPropertyEvaluation p:
{
PropertySymbol property = p.Property;
var outputTemp = new BoundDagTemp(p.Syntax, property.Type, p);
BoundExpression output = _tempAllocator.GetTemp(outputTemp);
return(_factory.AssignmentExpression(output, _localRewriter.MakePropertyAccess(_factory.Syntax, input, property, LookupResultKind.Viable, property.Type, isLeftOfAssignment: false)));
}
case BoundDagDeconstructEvaluation d:
{
MethodSymbol method = d.DeconstructMethod;
var refKindBuilder = ArrayBuilder <RefKind> .GetInstance();
var argBuilder = ArrayBuilder <BoundExpression> .GetInstance();
BoundExpression receiver;
void addArg(RefKind refKind, BoundExpression expression)
{
refKindBuilder.Add(refKind);
argBuilder.Add(expression);
}
Debug.Assert(method.Name == WellKnownMemberNames.DeconstructMethodName);
int extensionExtra;
if (method.IsStatic)
{
Debug.Assert(method.IsExtensionMethod);
receiver = _factory.Type(method.ContainingType);
addArg(method.ParameterRefKinds[0], input);
extensionExtra = 1;
}
else
{
receiver = input;
extensionExtra = 0;
}
for (int i = extensionExtra; i < method.ParameterCount; i++)
{
ParameterSymbol parameter = method.Parameters[i];
Debug.Assert(parameter.RefKind == RefKind.Out);
var outputTemp = new BoundDagTemp(d.Syntax, parameter.Type, d, i - extensionExtra);
addArg(RefKind.Out, _tempAllocator.GetTemp(outputTemp));
}
return(_factory.Call(receiver, method, refKindBuilder.ToImmutableAndFree(), argBuilder.ToImmutableAndFree()));
}
case BoundDagTypeEvaluation t:
{
TypeSymbol inputType = input.Type;
Debug.Assert(inputType is { });
if (inputType.IsDynamic())
{
// Avoid using dynamic conversions for pattern-matching.
inputType = _factory.SpecialType(SpecialType.System_Object);
input = _factory.Convert(inputType, input);
}
TypeSymbol type = t.Type;
var outputTemp = new BoundDagTemp(t.Syntax, type, t);
BoundExpression output = _tempAllocator.GetTemp(outputTemp);
CompoundUseSiteInfo <AssemblySymbol> useSiteInfo = _localRewriter.GetNewCompoundUseSiteInfo();
Conversion conversion = _factory.Compilation.Conversions.ClassifyBuiltInConversion(inputType, output.Type, ref useSiteInfo);
_localRewriter._diagnostics.Add(t.Syntax, useSiteInfo);
BoundExpression evaluated;
if (conversion.Exists)
{
if (conversion.Kind == ConversionKind.ExplicitNullable &&
inputType.GetNullableUnderlyingType().Equals(output.Type, TypeCompareKind.AllIgnoreOptions) &&
_localRewriter.TryGetNullableMethod(t.Syntax, inputType, SpecialMember.System_Nullable_T_GetValueOrDefault, out MethodSymbol getValueOrDefault))
{
// As a special case, since the null test has already been done we can use Nullable<T>.GetValueOrDefault
evaluated = _factory.Call(input, getValueOrDefault);
}
else
{
evaluated = _factory.Convert(type, input, conversion);
}
}
else
{
evaluated = _factory.As(input, type);
}
return(_factory.AssignmentExpression(output, evaluated));
}
/// <summary>
/// If the extension method is applicable based on the "this" argument type, return
/// the method constructed with the inferred type arguments. If the method is not an
/// unconstructed generic method, type inference is skipped. If the method is not
/// applicable, or if constraints when inferring type parameters from the "this" type
/// are not satisfied, the return value is null.
/// </summary>
/// <param name="compilation">Compilation used to check constraints. The latest language version is assumed if this is null.</param>
private static MethodSymbol InferExtensionMethodTypeArguments(MethodSymbol method, TypeSymbol thisType, CSharpCompilation compilation, ref HashSet <DiagnosticInfo> useSiteDiagnostics)
{
Debug.Assert(method.IsExtensionMethod);
Debug.Assert((object)thisType != null);
if (!method.IsGenericMethod || method != method.ConstructedFrom)
{
return(method);
}
// We never resolve extension methods on a dynamic receiver.
if (thisType.IsDynamic())
{
return(null);
}
var containingAssembly = method.ContainingAssembly;
var errorNamespace = containingAssembly.GlobalNamespace;
var conversions = new TypeConversions(containingAssembly.CorLibrary);
// There is absolutely no plausible syntax/tree that we could use for these
// synthesized literals. We could be speculatively binding a call to a PE method.
var syntaxTree = CSharpSyntaxTree.Dummy;
var syntax = (CSharpSyntaxNode)syntaxTree.GetRoot();
// Create an argument value for the "this" argument of specific type,
// and pass the same bad argument value for all other arguments.
var thisArgumentValue = new BoundLiteral(syntax, ConstantValue.Bad, thisType)
{
WasCompilerGenerated = true
};
var otherArgumentType = new ExtendedErrorTypeSymbol(errorNamespace, name: string.Empty, arity: 0, errorInfo: null, unreported: false);
var otherArgumentValue = new BoundLiteral(syntax, ConstantValue.Bad, otherArgumentType)
{
WasCompilerGenerated = true
};
var paramCount = method.ParameterCount;
var arguments = new BoundExpression[paramCount];
for (int i = 0; i < paramCount; i++)
{
var argument = (i == 0) ? thisArgumentValue : otherArgumentValue;
arguments[i] = argument;
}
var typeArgs = MethodTypeInferrer.InferTypeArgumentsFromFirstArgument(
conversions,
method,
arguments.AsImmutable(),
useSiteDiagnostics: ref useSiteDiagnostics);
if (typeArgs.IsDefault)
{
return(null);
}
// For the purpose of constraint checks we use error type symbol in place of type arguments that we couldn't infer from the first argument.
// This prevents constraint checking from failing for corresponding type parameters.
int firstNullInTypeArgs = -1;
var notInferredTypeParameters = PooledHashSet <TypeParameterSymbol> .GetInstance();
var typeParams = method.TypeParameters;
var typeArgsForConstraintsCheck = typeArgs;
for (int i = 0; i < typeArgsForConstraintsCheck.Length; i++)
{
if (!typeArgsForConstraintsCheck[i].HasType)
{
firstNullInTypeArgs = i;
var builder = ArrayBuilder <TypeWithAnnotations> .GetInstance();
builder.AddRange(typeArgsForConstraintsCheck, firstNullInTypeArgs);
for (; i < typeArgsForConstraintsCheck.Length; i++)
{
var typeArg = typeArgsForConstraintsCheck[i];
if (!typeArg.HasType)
{
notInferredTypeParameters.Add(typeParams[i]);
builder.Add(TypeWithAnnotations.Create(ErrorTypeSymbol.UnknownResultType));
}
else
{
builder.Add(typeArg);
}
}
typeArgsForConstraintsCheck = builder.ToImmutableAndFree();
break;
}
}
// Check constraints.
var diagnosticsBuilder = ArrayBuilder <TypeParameterDiagnosticInfo> .GetInstance();
var substitution = new TypeMap(typeParams, typeArgsForConstraintsCheck);
ArrayBuilder <TypeParameterDiagnosticInfo> useSiteDiagnosticsBuilder = null;
var success = method.CheckConstraints(conversions, substitution, typeParams, typeArgsForConstraintsCheck, compilation, diagnosticsBuilder, nullabilityDiagnosticsBuilderOpt: null, ref useSiteDiagnosticsBuilder,
ignoreTypeConstraintsDependentOnTypeParametersOpt: notInferredTypeParameters.Count > 0 ? notInferredTypeParameters : null);
diagnosticsBuilder.Free();
notInferredTypeParameters.Free();
if (useSiteDiagnosticsBuilder != null && useSiteDiagnosticsBuilder.Count > 0)
{
if (useSiteDiagnostics == null)
{
useSiteDiagnostics = new HashSet <DiagnosticInfo>();
}
foreach (var diag in useSiteDiagnosticsBuilder)
{
useSiteDiagnostics.Add(diag.DiagnosticInfo);
}
}
if (!success)
{
return(null);
}
// For the purpose of construction we use original type parameters in place of type arguments that we couldn't infer from the first argument.
ImmutableArray <TypeWithAnnotations> typeArgsForConstruct = typeArgs;
if (typeArgs.Any(t => !t.HasType))
{
typeArgsForConstruct = typeArgs.ZipAsArray(
method.TypeParameters,
(t, tp) => t.HasType ? t : TypeWithAnnotations.Create(tp));
}
return(method.Construct(typeArgsForConstruct));
}
/// <summary>
/// Check that the pattern type is valid for the operand. Return true if an error was reported.
/// </summary>
private bool CheckValidPatternType(
CSharpSyntaxNode typeSyntax,
BoundExpression operand,
TypeSymbol operandType,
TypeSymbol patternType,
bool patternTypeWasInSource,
bool isVar,
DiagnosticBag diagnostics)
{
Debug.Assert((object)operandType != null);
Debug.Assert((object)patternType != null);
// Because we do not support recursive patterns, we always have an operand
Debug.Assert((object)operand != null);
// Once we support recursive patterns that will be relaxed.
if (operandType.IsErrorType() || patternType.IsErrorType())
{
return(false);
}
else if (patternType.IsNullableType() && !isVar && patternTypeWasInSource)
{
// It is an error to use pattern-matching with a nullable type, because you'll never get null. Use the underlying type.
Error(diagnostics, ErrorCode.ERR_PatternNullableType, typeSyntax, patternType, patternType.GetNullableUnderlyingType());
return(true);
}
else if (patternType.IsStatic)
{
Error(diagnostics, ErrorCode.ERR_VarDeclIsStaticClass, typeSyntax, patternType);
return(true);
}
else if (!isVar)
{
if (patternType.IsDynamic())
{
Error(diagnostics, ErrorCode.ERR_PatternDynamicType, typeSyntax);
return(true);
}
HashSet <DiagnosticInfo> useSiteDiagnostics = null;
Conversion conversion =
operand != null
? this.Conversions.ClassifyConversionFromExpression(operand, patternType, ref useSiteDiagnostics, forCast : true)
: this.Conversions.ClassifyConversionFromType(operandType, patternType, ref useSiteDiagnostics, forCast: true);
diagnostics.Add(typeSyntax, useSiteDiagnostics);
switch (conversion.Kind)
{
case ConversionKind.ExplicitDynamic:
case ConversionKind.ImplicitDynamic:
// Since the input was `dynamic`, which is equivalent to `object`, there must also
// exist some unboxing, identity, or reference conversion as well, making the conversion legal.
case ConversionKind.Boxing:
case ConversionKind.ExplicitNullable:
case ConversionKind.ExplicitReference:
case ConversionKind.Identity:
case ConversionKind.ImplicitReference:
case ConversionKind.Unboxing:
case ConversionKind.NullLiteral:
case ConversionKind.ImplicitNullable:
// these are the conversions allowed by a pattern match
break;
//case ConversionKind.ExplicitNumeric: // we do not perform numeric conversions of the operand
//case ConversionKind.ImplicitConstant:
//case ConversionKind.ImplicitNumeric:
default:
Error(diagnostics, ErrorCode.ERR_PatternWrongType, typeSyntax, operandType, patternType);
return(true);
}
}
return(false);
}
private BoundExpression MakeUnaryOperator(
BoundUnaryOperator oldNode,
UnaryOperatorKind kind,
CSharpSyntaxNode syntax,
MethodSymbol method,
BoundExpression loweredOperand,
TypeSymbol type)
{
if (kind.IsDynamic())
{
Debug.Assert(kind == UnaryOperatorKind.DynamicTrue && type.SpecialType == SpecialType.System_Boolean || type.IsDynamic());
Debug.Assert((object)method == null);
// Logical operators on boxed Boolean constants:
var constant = UnboxConstant(loweredOperand);
if (constant == ConstantValue.True || constant == ConstantValue.False)
{
if (kind == UnaryOperatorKind.DynamicTrue)
{
return(factory.Literal(constant.BooleanValue));
}
else if (kind == UnaryOperatorKind.DynamicLogicalNegation)
{
return(MakeConversion(factory.Literal(!constant.BooleanValue), type, @checked: false));
}
}
return(dynamicFactory.MakeDynamicUnaryOperator(kind, loweredOperand, type).ToExpression());
}
else if (kind.IsLifted())
{
if (!inExpressionLambda)
{
return(LowerLiftedUnaryOperator(kind, syntax, method, loweredOperand, type));
}
}
else if (kind.IsUserDefined())
{
Debug.Assert((object)method != null);
Debug.Assert(type == method.ReturnType);
if (!inExpressionLambda || kind == UnaryOperatorKind.UserDefinedTrue || kind == UnaryOperatorKind.UserDefinedFalse)
{
return(BoundCall.Synthesized(syntax, null, method, loweredOperand));
}
}
else if (kind.Operator() == UnaryOperatorKind.UnaryPlus)
{
// We do not call the operator even for decimal; we simply optimize it away entirely.
return(loweredOperand);
}
if (kind == UnaryOperatorKind.EnumBitwiseComplement)
{
var underlyingType = loweredOperand.Type.GetEnumUnderlyingType();
var upconvertSpecialType = Binder.GetEnumPromotedType(underlyingType.SpecialType);
var upconvertType = upconvertSpecialType == underlyingType.SpecialType ?
underlyingType :
compilation.GetSpecialType(upconvertSpecialType);
var newOperand = MakeConversion(loweredOperand, upconvertType, false);
UnaryOperatorKind newKind = kind.Operator().WithType(upconvertSpecialType);
var newNode = (oldNode != null) ?
oldNode.Update(
newKind,
newOperand,
oldNode.ConstantValueOpt,
method,
newOperand.ResultKind,
upconvertType) :
new BoundUnaryOperator(
syntax,
newKind,
newOperand,
null,
method,
LookupResultKind.Viable,
upconvertType);
return(MakeConversion(newNode.Syntax, newNode, ConversionKind.ExplicitEnumeration, type, @checked: false));
}
if (kind == UnaryOperatorKind.DecimalUnaryMinus)
{
method = (MethodSymbol)this.compilation.Assembly.GetSpecialTypeMember(SpecialMember.System_Decimal__op_UnaryNegation);
if (!inExpressionLambda)
{
return(BoundCall.Synthesized(syntax, null, method, loweredOperand));
}
}
return((oldNode != null) ?
oldNode.Update(kind, loweredOperand, oldNode.ConstantValueOpt, method, oldNode.ResultKind, type) :
new BoundUnaryOperator(syntax, kind, loweredOperand, null, method, LookupResultKind.Viable, type));
}
/// <summary>
/// If the extension method is applicable based on the "this" argument type, return
/// the method constructed with the inferred type arguments. If the method is not an
/// unconstructed generic method, type inference is skipped. If the method is not
/// applicable, or if constraints when inferring type parameters from the "this" type
/// are not satisfied, the return value is null.
/// </summary>
private static MethodSymbol InferExtensionMethodTypeArguments(MethodSymbol method, TypeSymbol thisType, ref HashSet <DiagnosticInfo> useSiteDiagnostics)
{
Debug.Assert(method.IsExtensionMethod);
Debug.Assert((object)thisType != null);
if (!method.IsGenericMethod || method != method.ConstructedFrom)
{
return(method);
}
// We never resolve extension methods on a dynamic receiver.
if (thisType.IsDynamic())
{
return(null);
}
var containingAssembly = method.ContainingAssembly;
var errorNamespace = containingAssembly.GlobalNamespace;
var conversions = new TypeConversions(containingAssembly.CorLibrary);
// There is absolutely no plausible syntax/tree that we could use for these
// synthesized literals. We could be speculatively binding a call to a PE method.
var syntaxTree = CSharpSyntaxTree.Dummy;
var syntax = (CSharpSyntaxNode)syntaxTree.GetRoot();
// Create an argument value for the "this" argument of specific type,
// and pass the same bad argument value for all other arguments.
var thisArgumentValue = new BoundLiteral(syntax, ConstantValue.Bad, thisType)
{
WasCompilerGenerated = true
};
var otherArgumentType = new ExtendedErrorTypeSymbol(errorNamespace, name: string.Empty, arity: 0, errorInfo: null, unreported: false);
var otherArgumentValue = new BoundLiteral(syntax, ConstantValue.Bad, otherArgumentType)
{
WasCompilerGenerated = true
};
var paramCount = method.ParameterCount;
var arguments = new BoundExpression[paramCount];
for (int i = 0; i < paramCount; i++)
{
var argument = (i == 0) ? thisArgumentValue : otherArgumentValue;
arguments[i] = argument;
}
var typeArgs = MethodTypeInferrer.InferTypeArgumentsFromFirstArgument(
conversions,
method,
arguments.AsImmutable(),
useSiteDiagnostics: ref useSiteDiagnostics);
if (typeArgs.IsDefault)
{
return(null);
}
// For the purpose of construction we use original type parameters in place of type arguments that we couldn't infer from the first argument.
ImmutableArray <TypeWithAnnotations> typeArgsForConstruct = typeArgs;
if (typeArgs.Any(t => !t.HasType))
{
typeArgsForConstruct = typeArgs.ZipAsArray(
method.TypeParameters,
(t, tp) => t.HasType ? t : TypeWithAnnotations.Create(tp));
}
return(method.Construct(typeArgsForConstruct));
}
private ForEachEnumeratorInfo.Builder GetDefaultEnumeratorInfo(ForEachEnumeratorInfo.Builder builder, DiagnosticBag diagnostics, TypeSymbol collectionExprType)
{
// NOTE: for arrays, we won't actually use any of these members - they're just for the API.
builder.CollectionType = GetSpecialType(SpecialType.System_Collections_IEnumerable, diagnostics, _syntax);
if (collectionExprType.IsDynamic())
{
builder.ElementType = _syntax.Type.IsVar ?
(TypeSymbol)DynamicTypeSymbol.Instance :
GetSpecialType(SpecialType.System_Object, diagnostics, _syntax);
}
else
{
builder.ElementType = collectionExprType.SpecialType == SpecialType.System_String?
GetSpecialType(SpecialType.System_Char, diagnostics, _syntax) :
((ArrayTypeSymbol)collectionExprType).ElementType;
}
// CONSIDER:
// For arrays and string none of these members will actually be emitted, so it seems strange to prevent compilation if they can't be found.
// skip this work in the batch case?
builder.GetEnumeratorMethod = (MethodSymbol)GetSpecialTypeMember(SpecialMember.System_Collections_IEnumerable__GetEnumerator, diagnostics, _syntax);
builder.CurrentPropertyGetter = (MethodSymbol)GetSpecialTypeMember(SpecialMember.System_Collections_IEnumerator__get_Current, diagnostics, _syntax);
builder.MoveNextMethod = (MethodSymbol)GetSpecialTypeMember(SpecialMember.System_Collections_IEnumerator__MoveNext, diagnostics, _syntax);
Debug.Assert((object)builder.GetEnumeratorMethod == null ||
builder.GetEnumeratorMethod.ReturnType == this.Compilation.GetSpecialType(SpecialType.System_Collections_IEnumerator));
// We don't know the runtime type, so we will have to insert a runtime check for IDisposable (with a conditional call to IDisposable.Dispose).
builder.NeedsDisposeMethod = true;
return builder;
}
/// <summary>
/// Returns the better type amongst the two, with some possible modifications (dynamic/object or tuple names).
/// </summary>
private TypeSymbol Better(TypeSymbol type1, TypeSymbol type2, ref HashSet<DiagnosticInfo> useSiteDiagnostics)
{
// Anything is better than an error sym.
if (type1.IsErrorType())
{
return type2;
}
if ((object)type2 == null || type2.IsErrorType())
{
return type1;
}
var t1tot2 = _conversions.ClassifyImplicitConversionFromType(type1, type2, ref useSiteDiagnostics).Exists;
var t2tot1 = _conversions.ClassifyImplicitConversionFromType(type2, type1, ref useSiteDiagnostics).Exists;
if (t1tot2 && t2tot1)
{
if (type1.IsDynamic())
{
return type1;
}
if (type2.IsDynamic())
{
return type2;
}
if (type1.Equals(type2, TypeCompareKind.IgnoreDynamicAndTupleNames))
{
return MethodTypeInferrer.MergeTupleNames(type1, type2, MethodTypeInferrer.MergeDynamic(type1, type2, type1, _conversions.CorLibrary), _conversions.CorLibrary);
}
return null;
}
if (t1tot2)
{
return type2;
}
if (t2tot1)
{
return type1;
}
return null;
}
private void TestUnaryIntrinsicSymbol(
UnaryOperatorKind op,
TypeSymbol type,
CSharpCompilation compilation,
SemanticModel semanticModel,
ExpressionSyntax node1,
ExpressionSyntax node2,
ExpressionSyntax node3,
ExpressionSyntax node4
)
{
SymbolInfo info1 = semanticModel.GetSymbolInfo(node1);
Assert.Equal(type.IsDynamic() ? CandidateReason.LateBound : CandidateReason.None, info1.CandidateReason);
Assert.Equal(0, info1.CandidateSymbols.Length);
var symbol1 = (MethodSymbol)info1.Symbol;
var symbol2 = semanticModel.GetSymbolInfo(node2).Symbol;
var symbol3 = (MethodSymbol)semanticModel.GetSymbolInfo(node3).Symbol;
var symbol4 = semanticModel.GetSymbolInfo(node4).Symbol;
Assert.Equal(symbol1, symbol3);
if ((object)symbol1 != null)
{
Assert.NotSame(symbol1, symbol3);
Assert.Equal(symbol1.GetHashCode(), symbol3.GetHashCode());
Assert.Equal(symbol1.Parameters[0], symbol3.Parameters[0]);
Assert.Equal(symbol1.Parameters[0].GetHashCode(), symbol3.Parameters[0].GetHashCode());
}
Assert.Equal(symbol2, symbol4);
TypeSymbol underlying = type;
if (op == UnaryOperatorKind.BitwiseComplement ||
op == UnaryOperatorKind.PrefixDecrement || op == UnaryOperatorKind.PrefixIncrement ||
op == UnaryOperatorKind.PostfixDecrement || op == UnaryOperatorKind.PostfixIncrement)
{
underlying = type.EnumUnderlyingType();
}
UnaryOperatorKind result = OverloadResolution.UnopEasyOut.OpKind(op, underlying);
UnaryOperatorSignature signature;
if (result == UnaryOperatorKind.Error)
{
if (type.IsDynamic())
{
signature = new UnaryOperatorSignature(op | UnaryOperatorKind.Dynamic, type, type);
}
else if (type.IsPointerType() &&
(op == UnaryOperatorKind.PrefixDecrement || op == UnaryOperatorKind.PrefixIncrement ||
op == UnaryOperatorKind.PostfixDecrement || op == UnaryOperatorKind.PostfixIncrement))
{
signature = new UnaryOperatorSignature(op | UnaryOperatorKind.Pointer, type, type);
}
else
{
Assert.Null(symbol1);
Assert.Null(symbol2);
Assert.Null(symbol3);
Assert.Null(symbol4);
return;
}
}
else
{
signature = compilation.builtInOperators.GetSignature(result);
if ((object)underlying != (object)type)
{
Assert.Equal(underlying, signature.OperandType);
Assert.Equal(underlying, signature.ReturnType);
signature = new UnaryOperatorSignature(signature.Kind, type, type);
}
}
Assert.NotNull(symbol1);
string containerName = signature.OperandType.ToTestDisplayString();
string returnName = signature.ReturnType.ToTestDisplayString();
if (op == UnaryOperatorKind.LogicalNegation && type.IsEnumType())
{
containerName = type.ToTestDisplayString();
returnName = containerName;
}
Assert.Equal(String.Format("{2} {0}.{1}({0} value)",
containerName,
OperatorFacts.UnaryOperatorNameFromOperatorKind(op),
returnName),
symbol1.ToTestDisplayString());
Assert.Equal(MethodKind.BuiltinOperator, symbol1.MethodKind);
Assert.True(symbol1.IsImplicitlyDeclared);
bool expectChecked = false;
switch (op)
{
case UnaryOperatorKind.UnaryMinus:
expectChecked = (type.IsDynamic() || symbol1.ContainingType.EnumUnderlyingType().SpecialType.IsIntegralType());
break;
case UnaryOperatorKind.PrefixDecrement:
case UnaryOperatorKind.PrefixIncrement:
case UnaryOperatorKind.PostfixDecrement:
case UnaryOperatorKind.PostfixIncrement:
expectChecked = (type.IsDynamic() || type.IsPointerType() ||
symbol1.ContainingType.EnumUnderlyingType().SpecialType.IsIntegralType() ||
symbol1.ContainingType.SpecialType == SpecialType.System_Char);
break;
default:
expectChecked = type.IsDynamic();
break;
}
Assert.Equal(expectChecked, symbol1.IsCheckedBuiltin);
Assert.False(symbol1.IsGenericMethod);
Assert.False(symbol1.IsExtensionMethod);
Assert.False(symbol1.IsExtern);
Assert.False(symbol1.CanBeReferencedByName);
Assert.Null(symbol1.DeclaringCompilation);
Assert.Equal(symbol1.Name, symbol1.MetadataName);
Assert.Same(symbol1.ContainingSymbol, symbol1.Parameters[0].Type);
Assert.Equal(0, symbol1.Locations.Length);
Assert.Null(symbol1.GetDocumentationCommentId());
Assert.Equal("", symbol1.GetDocumentationCommentXml());
Assert.True(symbol1.HasSpecialName);
Assert.True(symbol1.IsStatic);
Assert.Equal(Accessibility.Public, symbol1.DeclaredAccessibility);
Assert.False(symbol1.HidesBaseMethodsByName);
Assert.False(symbol1.IsOverride);
Assert.False(symbol1.IsVirtual);
Assert.False(symbol1.IsAbstract);
Assert.False(symbol1.IsSealed);
Assert.Equal(1, symbol1.ParameterCount);
Assert.Equal(0, symbol1.Parameters[0].Ordinal);
var otherSymbol = (MethodSymbol)semanticModel.GetSymbolInfo(node1).Symbol;
Assert.Equal(symbol1, otherSymbol);
if (type.IsValueType && !type.IsPointerType())
{
Assert.Equal(symbol1, symbol2);
return;
}
Assert.Null(symbol2);
}
internal override BoundStatement BindUsingStatementParts(DiagnosticBag diagnostics, Binder originalBinder)
{
ExpressionSyntax expressionSyntax = TargetExpressionSyntax;
VariableDeclarationSyntax declarationSyntax = _syntax.Declaration;
bool hasAwait = _syntax.AwaitKeyword.Kind() != default;
Debug.Assert((expressionSyntax == null) ^ (declarationSyntax == null)); // Can't have both or neither.
TypeSymbol disposableInterface = getDisposableInterface(hasAwait);
Debug.Assert((object)disposableInterface != null);
bool hasErrors = ReportUseSiteDiagnostics(disposableInterface, diagnostics, hasAwait ? _syntax.AwaitKeyword : _syntax.UsingKeyword);
Conversion iDisposableConversion = Conversion.NoConversion;
BoundMultipleLocalDeclarations declarationsOpt = null;
BoundExpression expressionOpt = null;
AwaitableInfo awaitOpt = null;
TypeSymbol declarationTypeOpt = null;
if (expressionSyntax != null)
{
expressionOpt = this.BindTargetExpression(diagnostics, originalBinder);
hasErrors |= !initConversion(fromExpression: true);
}
else
{
ImmutableArray <BoundLocalDeclaration> declarations;
originalBinder.BindForOrUsingOrFixedDeclarations(declarationSyntax, LocalDeclarationKind.UsingVariable, diagnostics, out declarations);
Debug.Assert(!declarations.IsEmpty);
declarationsOpt = new BoundMultipleLocalDeclarations(declarationSyntax, declarations);
declarationTypeOpt = declarations[0].DeclaredType.Type;
if (declarationTypeOpt.IsDynamic())
{
iDisposableConversion = Conversion.ImplicitDynamic;
}
else
{
hasErrors |= !initConversion(fromExpression: false);
}
}
if (hasAwait)
{
TypeSymbol taskType = this.Compilation.GetWellKnownType(WellKnownType.System_Threading_Tasks_ValueTask);
hasErrors |= ReportUseSiteDiagnostics(taskType, diagnostics, _syntax.AwaitKeyword);
var resource = (SyntaxNode)expressionSyntax ?? declarationSyntax;
BoundExpression placeholder = new BoundAwaitableValuePlaceholder(resource, taskType).MakeCompilerGenerated();
awaitOpt = BindAwaitInfo(placeholder, resource, _syntax.AwaitKeyword.GetLocation(), diagnostics, ref hasErrors);
}
BoundStatement boundBody = originalBinder.BindPossibleEmbeddedStatement(_syntax.Statement, diagnostics);
Debug.Assert(GetDeclaredLocalsForScope(_syntax) == this.Locals);
return(new BoundUsingStatement(
_syntax,
this.Locals,
declarationsOpt,
expressionOpt,
iDisposableConversion,
boundBody,
awaitOpt,
hasErrors));
bool initConversion(bool fromExpression)
{
HashSet <DiagnosticInfo> useSiteDiagnostics = null;
iDisposableConversion = classifyConversion(fromExpression, disposableInterface, ref useSiteDiagnostics);
diagnostics.Add(fromExpression ? (CSharpSyntaxNode)expressionSyntax : declarationSyntax, useSiteDiagnostics);
if (iDisposableConversion.IsImplicit)
{
return(true);
}
TypeSymbol type = fromExpression ? expressionOpt.Type : declarationTypeOpt;
if (type is null || !type.IsErrorType())
{
// Retry with a different assumption about whether the `using` is async
TypeSymbol alternateInterface = getDisposableInterface(!hasAwait);
HashSet <DiagnosticInfo> ignored = null;
Conversion alternateConversion = classifyConversion(fromExpression, alternateInterface, ref ignored);
bool wrongAsync = alternateConversion.IsImplicit;
ErrorCode errorCode = wrongAsync
? (hasAwait ? ErrorCode.ERR_NoConvToIAsyncDispWrongAsync : ErrorCode.ERR_NoConvToIDispWrongAsync)
: (hasAwait ? ErrorCode.ERR_NoConvToIAsyncDisp : ErrorCode.ERR_NoConvToIDisp);
Error(diagnostics, errorCode, (CSharpSyntaxNode)declarationSyntax ?? expressionSyntax, declarationTypeOpt ?? expressionOpt.Display);
}
return(false);
}
Conversion classifyConversion(bool fromExpression, TypeSymbol targetInterface, ref HashSet <DiagnosticInfo> diag)
{
return(fromExpression ?
originalBinder.Conversions.ClassifyImplicitConversionFromExpression(expressionOpt, targetInterface, ref diag) :
originalBinder.Conversions.ClassifyImplicitConversionFromType(declarationTypeOpt, targetInterface, ref diag));
}
TypeSymbol getDisposableInterface(bool isAsync)
{
return(isAsync
? this.Compilation.GetWellKnownType(WellKnownType.System_IAsyncDisposable)
: this.Compilation.GetSpecialType(SpecialType.System_IDisposable));
}
}
private bool ImplicitConversionExists(TypeSymbol source, TypeSymbol destination, ref HashSet<DiagnosticInfo> useSiteDiagnostics)
{
// SPEC VIOLATION: For the purpose of algorithm in Fix method, dynamic type is not considered convertible to any other type, including object.
if (source.IsDynamic() && !destination.IsDynamic())
{
return false;
}
return _conversions.ClassifyImplicitConversionFromType(source, destination, ref useSiteDiagnostics).Exists;
}
internal static bool TryCreate(SyntheticBoundNodeFactory F, MethodSymbol method, TypeMap typeMap, out AsyncMethodBuilderMemberCollection collection)
{
if (method.IsVoidReturningAsync())
{
return(TryCreate(
F: F,
builderType: F.WellKnownType(WellKnownType.System_Runtime_CompilerServices_AsyncVoidMethodBuilder),
resultType: F.SpecialType(SpecialType.System_Void),
setException: WellKnownMember.System_Runtime_CompilerServices_AsyncVoidMethodBuilder__SetException,
setResult: WellKnownMember.System_Runtime_CompilerServices_AsyncVoidMethodBuilder__SetResult,
awaitOnCompleted: WellKnownMember.System_Runtime_CompilerServices_AsyncVoidMethodBuilder__AwaitOnCompleted,
awaitUnsafeOnCompleted: WellKnownMember.System_Runtime_CompilerServices_AsyncVoidMethodBuilder__AwaitUnsafeOnCompleted,
start: WellKnownMember.System_Runtime_CompilerServices_AsyncVoidMethodBuilder__Start_T,
setStateMachine: WellKnownMember.System_Runtime_CompilerServices_AsyncVoidMethodBuilder__SetStateMachine,
task: null,
collection: out collection));
}
if (method.IsTaskReturningAsync(F.Compilation))
{
NamedTypeSymbol builderType = F.WellKnownType(WellKnownType.System_Runtime_CompilerServices_AsyncTaskMethodBuilder);
PropertySymbol task;
if (!TryGetWellKnownPropertyAsMember(F, WellKnownMember.System_Runtime_CompilerServices_AsyncTaskMethodBuilder__Task, builderType, out task))
{
collection = default(AsyncMethodBuilderMemberCollection);
return(false);
}
return(TryCreate(
F: F,
builderType: F.WellKnownType(WellKnownType.System_Runtime_CompilerServices_AsyncTaskMethodBuilder),
resultType: F.SpecialType(SpecialType.System_Void),
setException: WellKnownMember.System_Runtime_CompilerServices_AsyncTaskMethodBuilder__SetException,
setResult: WellKnownMember.System_Runtime_CompilerServices_AsyncTaskMethodBuilder__SetResult,
awaitOnCompleted: WellKnownMember.System_Runtime_CompilerServices_AsyncTaskMethodBuilder__AwaitOnCompleted,
awaitUnsafeOnCompleted: WellKnownMember.System_Runtime_CompilerServices_AsyncTaskMethodBuilder__AwaitUnsafeOnCompleted,
start: WellKnownMember.System_Runtime_CompilerServices_AsyncTaskMethodBuilder__Start_T,
setStateMachine: WellKnownMember.System_Runtime_CompilerServices_AsyncTaskMethodBuilder__SetStateMachine,
task: task,
collection: out collection));
}
if (method.IsGenericTaskReturningAsync(F.Compilation))
{
TypeSymbol resultType = method.ReturnType.GetMemberTypeArgumentsNoUseSiteDiagnostics().Single();
if (resultType.IsDynamic())
{
resultType = F.SpecialType(SpecialType.System_Object);
}
if (typeMap != null)
{
resultType = typeMap.SubstituteType(resultType);
}
NamedTypeSymbol builderType = F.WellKnownType(WellKnownType.System_Runtime_CompilerServices_AsyncTaskMethodBuilder_T).Construct(resultType);
PropertySymbol task;
if (!TryGetWellKnownPropertyAsMember(F, WellKnownMember.System_Runtime_CompilerServices_AsyncTaskMethodBuilder_T__Task, builderType, out task))
{
collection = default(AsyncMethodBuilderMemberCollection);
return(false);
}
return(TryCreate(
F: F,
builderType: builderType,
resultType: resultType,
setException: WellKnownMember.System_Runtime_CompilerServices_AsyncTaskMethodBuilder_T__SetException,
setResult: WellKnownMember.System_Runtime_CompilerServices_AsyncTaskMethodBuilder_T__SetResult,
awaitOnCompleted: WellKnownMember.System_Runtime_CompilerServices_AsyncTaskMethodBuilder_T__AwaitOnCompleted,
awaitUnsafeOnCompleted: WellKnownMember.System_Runtime_CompilerServices_AsyncTaskMethodBuilder_T__AwaitUnsafeOnCompleted,
start: WellKnownMember.System_Runtime_CompilerServices_AsyncTaskMethodBuilder_T__Start_T,
setStateMachine: WellKnownMember.System_Runtime_CompilerServices_AsyncTaskMethodBuilder_T__SetStateMachine,
task: task,
collection: out collection));
}
throw ExceptionUtilities.UnexpectedValue(method);
}
// Determine if the conversion can actually overflow at runtime. If not, no need to generate a checked instruction.
private static bool NeedsChecked(TypeSymbol source, TypeSymbol target)
{
Debug.Assert((object)target != null);
if ((object)source == null)
{
return false;
}
if (source.IsDynamic())
{
return true;
}
SpecialType sourceST = source.StrippedType().EnumUnderlyingType().SpecialType;
SpecialType targetST = target.StrippedType().EnumUnderlyingType().SpecialType;
// integral to double or float is never checked, but float/double to integral
// may be checked.
bool sourceIsNumeric = SpecialType.System_Char <= sourceST && sourceST <= SpecialType.System_Double;
bool targetIsNumeric = SpecialType.System_Char <= targetST && targetST <= SpecialType.System_UInt64;
return
sourceIsNumeric && target.IsPointerType() ||
targetIsNumeric && source.IsPointerType() ||
sourceIsNumeric && targetIsNumeric && needsChecked[sourceST - SpecialType.System_Char, targetST - SpecialType.System_Char];
}
internal override BoundStatement BindUsingStatementParts(DiagnosticBag diagnostics, Binder originalBinder)
{
ExpressionSyntax expressionSyntax = TargetExpressionSyntax;
VariableDeclarationSyntax declarationSyntax = _syntax.Declaration;
Debug.Assert((expressionSyntax == null) ^ (declarationSyntax == null)); // Can't have both or neither.
bool hasErrors = false;
BoundMultipleLocalDeclarations declarationsOpt = null;
BoundExpression expressionOpt = null;
Conversion iDisposableConversion = Conversion.NoConversion;
TypeSymbol iDisposable = this.Compilation.GetSpecialType(SpecialType.System_IDisposable); // no need for diagnostics, so use the Compilation version
Debug.Assert((object)iDisposable != null);
if (expressionSyntax != null)
{
expressionOpt = this.BindTargetExpression(diagnostics, originalBinder);
HashSet <DiagnosticInfo> useSiteDiagnostics = null;
iDisposableConversion = originalBinder.Conversions.ClassifyImplicitConversionFromExpression(expressionOpt, iDisposable, ref useSiteDiagnostics);
diagnostics.Add(expressionSyntax, useSiteDiagnostics);
if (!iDisposableConversion.IsImplicit)
{
TypeSymbol expressionType = expressionOpt.Type;
if ((object)expressionType == null || !expressionType.IsErrorType())
{
Error(diagnostics, ErrorCode.ERR_NoConvToIDisp, expressionSyntax, expressionOpt.Display);
}
hasErrors = true;
}
}
else
{
ImmutableArray <BoundLocalDeclaration> declarations;
originalBinder.BindForOrUsingOrFixedDeclarations(declarationSyntax, LocalDeclarationKind.UsingVariable, diagnostics, out declarations);
Debug.Assert(!declarations.IsEmpty);
declarationsOpt = new BoundMultipleLocalDeclarations(declarationSyntax, declarations);
TypeSymbol declType = declarations[0].DeclaredType.Type;
if (declType.IsDynamic())
{
iDisposableConversion = Conversion.ImplicitDynamic;
}
else
{
HashSet <DiagnosticInfo> useSiteDiagnostics = null;
iDisposableConversion = originalBinder.Conversions.ClassifyImplicitConversionFromType(declType, iDisposable, ref useSiteDiagnostics);
diagnostics.Add(declarationSyntax, useSiteDiagnostics);
if (!iDisposableConversion.IsImplicit)
{
if (!declType.IsErrorType())
{
Error(diagnostics, ErrorCode.ERR_NoConvToIDisp, declarationSyntax, declType);
}
hasErrors = true;
}
}
}
BoundStatement boundBody = originalBinder.BindPossibleEmbeddedStatement(_syntax.Statement, diagnostics);
Debug.Assert(GetDeclaredLocalsForScope(_syntax) == this.Locals);
return(new BoundUsingStatement(
_syntax,
this.Locals,
declarationsOpt,
expressionOpt,
iDisposableConversion,
boundBody,
hasErrors));
}
/// <summary>
/// If the extension method is applicable based on the "this" argument type, return
/// the method constructed with the inferred type arguments. If the method is not an
/// unconstructed generic method, type inference is skipped. If the method is not
/// applicable, or if constraints when inferring type parameters from the "this" type
/// are not satisfied, the return value is null.
/// </summary>
public static MethodSymbol InferExtensionMethodTypeArguments(this MethodSymbol method, TypeSymbol thisType, Compilation compilation, ref HashSet<DiagnosticInfo> useSiteDiagnostics)
{
Debug.Assert(method.IsExtensionMethod);
Debug.Assert((object)thisType != null);
if (!method.IsGenericMethod || method != method.ConstructedFrom)
{
return method;
}
// We never resolve extension methods on a dynamic receiver.
if (thisType.IsDynamic())
{
return null;
}
var containingAssembly = method.ContainingAssembly;
var errorNamespace = containingAssembly.GlobalNamespace;
var conversions = new TypeConversions(containingAssembly.CorLibrary);
// There is absolutely no plausible syntax/tree that we could use for these
// synthesized literals. We could be speculatively binding a call to a PE method.
var syntaxTree = CSharpSyntaxTree.Dummy;
var syntax = (CSharpSyntaxNode)syntaxTree.GetRoot();
// Create an argument value for the "this" argument of specific type,
// and pass the same bad argument value for all other arguments.
var thisArgumentValue = new BoundLiteral(syntax, ConstantValue.Bad, thisType) { WasCompilerGenerated = true };
var otherArgumentType = new ExtendedErrorTypeSymbol(errorNamespace, name: string.Empty, arity: 0, errorInfo: null, unreported: false);
var otherArgumentValue = new BoundLiteral(syntax, ConstantValue.Bad, otherArgumentType) { WasCompilerGenerated = true };
var paramCount = method.ParameterCount;
var arguments = new BoundExpression[paramCount];
var argumentTypes = new TypeSymbol[paramCount];
for (int i = 0; i < paramCount; i++)
{
var argument = (i == 0) ? thisArgumentValue : otherArgumentValue;
arguments[i] = argument;
argumentTypes[i] = argument.Type;
}
var typeArgs = MethodTypeInferrer.InferTypeArgumentsFromFirstArgument(
conversions,
method,
argumentTypes.AsImmutableOrNull(),
arguments.AsImmutableOrNull(),
ref useSiteDiagnostics);
if (typeArgs.IsDefault)
{
return null;
}
// Check constraints.
var diagnosticsBuilder = ArrayBuilder<TypeParameterDiagnosticInfo>.GetInstance();
var typeParams = method.TypeParameters;
var substitution = new TypeMap(typeParams, typeArgs);
ArrayBuilder<TypeParameterDiagnosticInfo> useSiteDiagnosticsBuilder = null;
var success = method.CheckConstraints(conversions, substitution, method.TypeParameters, typeArgs, compilation, diagnosticsBuilder, ref useSiteDiagnosticsBuilder);
diagnosticsBuilder.Free();
if (useSiteDiagnosticsBuilder != null && useSiteDiagnosticsBuilder.Count > 0)
{
if (useSiteDiagnostics == null)
{
useSiteDiagnostics = new HashSet<DiagnosticInfo>();
}
foreach (var diag in useSiteDiagnosticsBuilder)
{
useSiteDiagnostics.Add(diag.DiagnosticInfo);
}
}
if (!success)
{
return null;
}
return method.Construct(typeArgs);
}
private TupleBinaryOperatorInfo BindTupleBinaryOperatorInfo(BinaryExpressionSyntax node, BinaryOperatorKind kind,
BoundExpression left, BoundExpression right, BindingDiagnosticBag diagnostics)
{
TypeSymbol leftType = left.Type;
TypeSymbol rightType = right.Type;
if ((object)leftType != null && leftType.IsDynamic() || (object)rightType != null && rightType.IsDynamic())
{
return(BindTupleDynamicBinaryOperatorSingleInfo(node, kind, left, right, diagnostics));
}
if (IsTupleBinaryOperation(left, right))
{
return(BindTupleBinaryOperatorNestedInfo(node, kind, left, right, diagnostics));
}
BoundExpression comparison = BindSimpleBinaryOperator(node, diagnostics, left, right);
switch (comparison)
{
case BoundLiteral _:
// this case handles `null == null` and the like
return(new TupleBinaryOperatorInfo.NullNull(kind));
case BoundBinaryOperator binary:
PrepareBoolConversionAndTruthOperator(binary.Type, node, kind, diagnostics, out Conversion conversionIntoBoolOperator, out UnaryOperatorSignature boolOperator);
CheckConstraintLanguageVersionAndRuntimeSupportForOperator(node, boolOperator.Method, boolOperator.ConstrainedToTypeOpt, diagnostics);
return(new TupleBinaryOperatorInfo.Single(binary.Left.Type, binary.Right.Type, binary.OperatorKind, binary.MethodOpt, binary.ConstrainedToTypeOpt, conversionIntoBoolOperator, boolOperator));
default:
throw ExceptionUtilities.UnexpectedValue(comparison);
}
}
private BoundExpression MakeUnaryOperator(
BoundUnaryOperator oldNode,
UnaryOperatorKind kind,
CSharpSyntaxNode syntax,
MethodSymbol method,
BoundExpression loweredOperand,
TypeSymbol type)
{
if (kind.IsDynamic())
{
Debug.Assert(kind == UnaryOperatorKind.DynamicTrue && type.SpecialType == SpecialType.System_Boolean || type.IsDynamic());
Debug.Assert((object)method == null);
// Logical operators on boxed Boolean constants:
var constant = UnboxConstant(loweredOperand);
if (constant == ConstantValue.True || constant == ConstantValue.False)
{
if (kind == UnaryOperatorKind.DynamicTrue)
{
return _factory.Literal(constant.BooleanValue);
}
else if (kind == UnaryOperatorKind.DynamicLogicalNegation)
{
return MakeConversionNode(_factory.Literal(!constant.BooleanValue), type, @checked: false);
}
}
return _dynamicFactory.MakeDynamicUnaryOperator(kind, loweredOperand, type).ToExpression();
}
else if (kind.IsLifted())
{
if (!_inExpressionLambda)
{
return LowerLiftedUnaryOperator(kind, syntax, method, loweredOperand, type);
}
}
else if (kind.IsUserDefined())
{
Debug.Assert((object)method != null);
Debug.Assert(type == method.ReturnType);
if (!_inExpressionLambda || kind == UnaryOperatorKind.UserDefinedTrue || kind == UnaryOperatorKind.UserDefinedFalse)
{
return BoundCall.Synthesized(syntax, null, method, loweredOperand);
}
}
else if (kind.Operator() == UnaryOperatorKind.UnaryPlus)
{
// We do not call the operator even for decimal; we simply optimize it away entirely.
return loweredOperand;
}
if (kind == UnaryOperatorKind.EnumBitwiseComplement)
{
var underlyingType = loweredOperand.Type.GetEnumUnderlyingType();
var upconvertSpecialType = Binder.GetEnumPromotedType(underlyingType.SpecialType);
var upconvertType = upconvertSpecialType == underlyingType.SpecialType ?
underlyingType :
_compilation.GetSpecialType(upconvertSpecialType);
var newOperand = MakeConversionNode(loweredOperand, upconvertType, false);
UnaryOperatorKind newKind = kind.Operator().WithType(upconvertSpecialType);
var newNode = (oldNode != null) ?
oldNode.Update(
newKind,
newOperand,
oldNode.ConstantValueOpt,
method,
newOperand.ResultKind,
upconvertType) :
new BoundUnaryOperator(
syntax,
newKind,
newOperand,
null,
method,
LookupResultKind.Viable,
upconvertType);
return MakeConversionNode(newNode.Syntax, newNode, Conversion.ExplicitEnumeration, type, @checked: false);
}
if (kind == UnaryOperatorKind.DecimalUnaryMinus)
{
method = (MethodSymbol)_compilation.Assembly.GetSpecialTypeMember(SpecialMember.System_Decimal__op_UnaryNegation);
if (!_inExpressionLambda)
{
return BoundCall.Synthesized(syntax, null, method, loweredOperand);
}
}
return (oldNode != null) ?
oldNode.Update(kind, loweredOperand, oldNode.ConstantValueOpt, method, oldNode.ResultKind, type) :
new BoundUnaryOperator(syntax, kind, loweredOperand, null, method, LookupResultKind.Viable, type);
}
/// <summary>
/// The spec describes an algorithm for finding the following types:
/// 1) Collection type
/// 2) Enumerator type
/// 3) Element type
///
/// The implementation details are a bit difference. If we're iterating over a string or an array, then we don't need to record anything
/// but the inferredType (in case the iteration variable is implicitly typed). If we're iterating over anything else, then we want the
/// inferred type plus a ForEachEnumeratorInfo.Builder with:
/// 1) Collection type
/// 2) Element type
/// 3) GetEnumerator method of the collection type (return type will be the enumerator type from the spec)
/// 4) Current property of the enumerator type
/// 5) MoveNext method of the enumerator type
///
/// The caller will have to do some extra conversion checks before creating a ForEachEnumeratorInfo for the BoundForEachStatement.
/// </summary>
/// <param name="builder">Builder to fill in (partially, all but conversions).</param>
/// <param name="collectionExpr">The expression over which to iterate.</param>
/// <param name="diagnostics">Populated with binding diagnostics.</param>
/// <returns>Partially populated (all but conversions) or null if there was an error.</returns>
private bool GetEnumeratorInfo(ref ForEachEnumeratorInfo.Builder builder, BoundExpression collectionExpr, DiagnosticBag diagnostics)
{
TypeSymbol collectionExprType = collectionExpr.Type;
if (collectionExpr.ConstantValue != null && collectionExpr.ConstantValue.IsNull)
{
// Spec seems to refer to null literals, but Dev10 reports anything known to be null.
Debug.Assert(collectionExpr.ConstantValue.IsNull); // only constant value with no type
diagnostics.Add(ErrorCode.ERR_NullNotValid, syntax.Expression.Location);
return(false);
}
if ((object)collectionExprType == null) // There's no way to enumerate something without a type.
{
// The null literal was caught above, so anything else with a null type is a method group or anonymous function
diagnostics.Add(ErrorCode.ERR_AnonMethGrpInForEach, syntax.Expression.Location, collectionExpr.Display);
// CONSIDER: dev10 also reports ERR_ForEachMissingMember (i.e. failed pattern match).
return(false);
}
if (collectionExpr.ResultKind == LookupResultKind.NotAValue)
{
// Short-circuiting to prevent strange behavior in the case where the collection
// expression is a type expression and the type is enumerable.
Debug.Assert(collectionExpr.HasAnyErrors); // should already have been reported
return(false);
}
// The spec specifically lists the collection, enumerator, and element types for arrays and dynamic.
if (collectionExprType.Kind == SymbolKind.ArrayType || collectionExprType.Kind == SymbolKind.DynamicType)
{
// NOTE: for arrays, we won't actually use any of these members - they're just for the API.
builder.CollectionType = GetSpecialType(SpecialType.System_Collections_IEnumerable, diagnostics, this.syntax);
builder.ElementType =
collectionExprType.IsDynamic() ?
(this.syntax.Type.IsVar ? (TypeSymbol)DynamicTypeSymbol.Instance : GetSpecialType(SpecialType.System_Object, diagnostics, this.syntax)) :
((ArrayTypeSymbol)collectionExprType).ElementType;
// CONSIDER:
// For arrays none of these members will actually be emitted, so it seems strange to prevent compilation if they can't be found.
// skip this work in the batch case? (If so, also special case string, which won't use the pattern methods.)
builder.GetEnumeratorMethod = (MethodSymbol)GetSpecialTypeMember(SpecialMember.System_Collections_IEnumerable__GetEnumerator, diagnostics, this.syntax);
builder.CurrentPropertyGetter = (MethodSymbol)GetSpecialTypeMember(SpecialMember.System_Collections_IEnumerator__get_Current, diagnostics, this.syntax);
builder.MoveNextMethod = (MethodSymbol)GetSpecialTypeMember(SpecialMember.System_Collections_IEnumerator__MoveNext, diagnostics, this.syntax);
Debug.Assert((object)builder.GetEnumeratorMethod == null ||
builder.GetEnumeratorMethod.ReturnType == this.Compilation.GetSpecialType(SpecialType.System_Collections_IEnumerator));
// We don't know the runtime type, so we will have to insert a runtime check for IDisposable (with a conditional call to IDisposable.Dispose).
builder.NeedsDisposeMethod = true;
return(true);
}
bool foundMultipleGenericIEnumerableInterfaces;
if (SatisfiesGetEnumeratorPattern(ref builder, collectionExprType, diagnostics))
{
Debug.Assert((object)builder.GetEnumeratorMethod != null);
builder.CollectionType = collectionExprType;
if (SatisfiesForEachPattern(ref builder, diagnostics))
{
builder.ElementType = ((PropertySymbol)builder.CurrentPropertyGetter.AssociatedSymbol).Type;
// NOTE: if IDisposable is not available at all, no diagnostics will be reported - we will just assume that
// the enumerator is not disposable. If it has IDisposable in its interface list, there will be a diagnostic there.
// If IDisposable is available but its Dispose method is not, then diagnostics will be reported only if the enumerator
// is potentially disposable.
var useSiteDiagnosticBag = DiagnosticBag.GetInstance();
TypeSymbol enumeratorType = builder.GetEnumeratorMethod.ReturnType;
HashSet <DiagnosticInfo> useSiteDiagnostics = null;
if (!enumeratorType.IsSealed || this.Conversions.ClassifyImplicitConversion(enumeratorType, this.Compilation.GetSpecialType(SpecialType.System_IDisposable), ref useSiteDiagnostics).IsImplicit)
{
builder.NeedsDisposeMethod = true;
diagnostics.AddRange(useSiteDiagnosticBag);
}
useSiteDiagnosticBag.Free();
diagnostics.Add(this.syntax, useSiteDiagnostics);
return(true);
}
MethodSymbol getEnumeratorMethod = builder.GetEnumeratorMethod;
diagnostics.Add(ErrorCode.ERR_BadGetEnumerator, this.syntax.Expression.Location, getEnumeratorMethod.ReturnType, getEnumeratorMethod);
return(false);
}
if (IsIEnumerable(collectionExprType))
{
// This indicates a problem with the special IEnumerable type - it should have satisfied the GetEnumerator pattern.
diagnostics.Add(ErrorCode.ERR_ForEachMissingMember, syntax.Expression.Location, collectionExprType, GetEnumeratorMethodName);
return(false);
}
if (AllInterfacesContainsIEnumerable(ref builder, collectionExprType, diagnostics, out foundMultipleGenericIEnumerableInterfaces))
{
CSharpSyntaxNode errorLocationSyntax = this.syntax.Expression;
if (foundMultipleGenericIEnumerableInterfaces)
{
diagnostics.Add(ErrorCode.ERR_MultipleIEnumOfT, errorLocationSyntax.Location, collectionExprType, this.Compilation.GetSpecialType(SpecialType.System_Collections_Generic_IEnumerable_T));
return(false);
}
Debug.Assert((object)builder.CollectionType != null);
NamedTypeSymbol collectionType = (NamedTypeSymbol)builder.CollectionType;
if (collectionType.IsGenericType)
{
// If the type is generic, we have to search for the methods
Debug.Assert(collectionType.OriginalDefinition.SpecialType == SpecialType.System_Collections_Generic_IEnumerable_T);
builder.ElementType = collectionType.TypeArgumentsNoUseSiteDiagnostics.Single();
MethodSymbol getEnumeratorMethod = (MethodSymbol)GetSpecialTypeMember(SpecialMember.System_Collections_Generic_IEnumerable_T__GetEnumerator, diagnostics, errorLocationSyntax);
if ((object)getEnumeratorMethod != null)
{
builder.GetEnumeratorMethod = getEnumeratorMethod.AsMember(collectionType);
TypeSymbol enumeratorType = builder.GetEnumeratorMethod.ReturnType;
Debug.Assert(enumeratorType.OriginalDefinition.SpecialType == SpecialType.System_Collections_Generic_IEnumerator_T);
MethodSymbol currentPropertyGetter = (MethodSymbol)GetSpecialTypeMember(SpecialMember.System_Collections_Generic_IEnumerator_T__get_Current, diagnostics, errorLocationSyntax);
if ((object)currentPropertyGetter != null)
{
builder.CurrentPropertyGetter = currentPropertyGetter.AsMember((NamedTypeSymbol)enumeratorType);
}
}
builder.MoveNextMethod = (MethodSymbol)GetSpecialTypeMember(SpecialMember.System_Collections_IEnumerator__MoveNext, diagnostics, errorLocationSyntax); // NOTE: MoveNext is actually inherited from System.Collections.IEnumerator
}
else
{
// Non-generic - use special members to avoid re-computing
Debug.Assert(collectionType.SpecialType == SpecialType.System_Collections_IEnumerable);
builder.ElementType = GetSpecialType(SpecialType.System_Object, diagnostics, errorLocationSyntax);
builder.GetEnumeratorMethod = (MethodSymbol)GetSpecialTypeMember(SpecialMember.System_Collections_IEnumerable__GetEnumerator, diagnostics, errorLocationSyntax);
builder.CurrentPropertyGetter = (MethodSymbol)GetSpecialTypeMember(SpecialMember.System_Collections_IEnumerator__get_Current, diagnostics, errorLocationSyntax);
builder.MoveNextMethod = (MethodSymbol)GetSpecialTypeMember(SpecialMember.System_Collections_IEnumerator__MoveNext, diagnostics, errorLocationSyntax);
Debug.Assert((object)builder.GetEnumeratorMethod == null ||
builder.GetEnumeratorMethod.ReturnType == GetSpecialType(SpecialType.System_Collections_IEnumerator, diagnostics, errorLocationSyntax));
}
// We don't know the runtime type, so we will have to insert a runtime check for IDisposable (with a conditional call to IDisposable.Dispose).
builder.NeedsDisposeMethod = true;
return(true);
}
if (!string.IsNullOrEmpty(collectionExprType.Name) || !collectionExpr.HasErrors)
{
diagnostics.Add(ErrorCode.ERR_ForEachMissingMember, syntax.Expression.Location, collectionExprType.ToDisplayString(), GetEnumeratorMethodName);
}
return(false);
}
private BoundBlock VisitAwaitExpression(BoundAwaitExpression node, BoundExpression resultPlace)
{
var expression = (BoundExpression)Visit(node.Expression);
resultPlace = (BoundExpression)Visit(resultPlace);
MethodSymbol getAwaiter = VisitMethodSymbol(node.GetAwaiter);
MethodSymbol getResult = VisitMethodSymbol(node.GetResult);
MethodSymbol isCompletedMethod = ((object)node.IsCompleted != null) ? VisitMethodSymbol(node.IsCompleted.GetMethod) : null;
TypeSymbol type = VisitType(node.Type);
LocalSymbol awaiterTemp;
if ((object)getResult == null)
{
awaiterTemp = F.SynthesizedLocal(DynamicTypeSymbol.Instance);
}
else if (type.IsDynamic())
{
var awaiterType = ((NamedTypeSymbol)getAwaiter.ReturnType).OriginalDefinition.Construct(F.SpecialType(SpecialType.System_Object));
awaiterTemp = F.SynthesizedLocal(awaiterType);
getResult = getResult.OriginalDefinition.AsMember(awaiterType);
isCompletedMethod = isCompletedMethod.OriginalDefinition.AsMember(awaiterType);
}
else
{
awaiterTemp = F.SynthesizedLocal(getAwaiter.ReturnType);
}
var awaitIfIncomplete = F.Block(
// temp $awaiterTemp = <expr>.GetAwaiter();
F.Assignment(
F.Local(awaiterTemp),
MakeCallMaybeDynamic(expression, getAwaiter, WellKnownMemberNames.GetAwaiter)),
// if(!($awaiterTemp.IsCompleted)) { ... }
F.If(
condition: F.Not(GenerateGetIsCompleted(awaiterTemp, isCompletedMethod)),
thenClause: GenerateAwaitForIncompleteTask(awaiterTemp)));
BoundExpression getResultCall = MakeCallMaybeDynamic(
F.Local(awaiterTemp),
getResult,
WellKnownMemberNames.GetResult,
resultsDiscarded: resultPlace == null);
var nullAwaiter = F.AssignmentExpression(F.Local(awaiterTemp), F.NullOrDefault(awaiterTemp.Type));
if (resultPlace != null && type.SpecialType != SpecialType.System_Void)
{
// $resultTemp = $awaiterTemp.GetResult();
// $awaiterTemp = null;
// $resultTemp
LocalSymbol resultTemp = F.SynthesizedLocal(type);
return(F.Block(
ImmutableArray.Create(awaiterTemp, resultTemp),
awaitIfIncomplete,
F.Assignment(F.Local(resultTemp), getResultCall),
F.ExpressionStatement(nullAwaiter),
F.Assignment(resultPlace, F.Local(resultTemp))));
}
else
{
// $awaiterTemp.GetResult();
// $awaiterTemp = null;
return(F.Block(
ImmutableArray.Create(awaiterTemp),
awaitIfIncomplete,
F.ExpressionStatement(getResultCall),
F.ExpressionStatement(nullAwaiter)));
}
}
/// <summary>
/// If the extension method is applicable based on the "this" argument type, return
/// the method constructed with the inferred type arguments. If the method is not an
/// unconstructed generic method, type inference is skipped. If the method is not
/// applicable, or if constraints when inferring type parameters from the "this" type
/// are not satisfied, the return value is null.
/// </summary>
public static MethodSymbol InferExtensionMethodTypeArguments(this MethodSymbol method, TypeSymbol thisType, Compilation compilation, ref HashSet <DiagnosticInfo> useSiteDiagnostics)
{
Debug.Assert(method.IsExtensionMethod);
Debug.Assert((object)thisType != null);
if (!method.IsGenericMethod || method != method.ConstructedFrom)
{
return(method);
}
// We never resolve extension methods on a dynamic receiver.
if (thisType.IsDynamic())
{
return(null);
}
var containingAssembly = method.ContainingAssembly;
var errorNamespace = containingAssembly.GlobalNamespace;
var conversions = new TypeConversions(containingAssembly.CorLibrary);
// There is absolutely no plausible syntax/tree that we could use for these
// synthesized literals. We could be speculatively binding a call to a PE method.
var syntaxTree = CSharpSyntaxTree.Dummy;
var syntax = (CSharpSyntaxNode)syntaxTree.GetRoot();
// Create an argument value for the "this" argument of specific type,
// and pass the same bad argument value for all other arguments.
var thisArgumentValue = new BoundLiteral(syntax, ConstantValue.Bad, thisType)
{
WasCompilerGenerated = true
};
var otherArgumentType = new ExtendedErrorTypeSymbol(errorNamespace, name: string.Empty, arity: 0, errorInfo: null, unreported: false);
var otherArgumentValue = new BoundLiteral(syntax, ConstantValue.Bad, otherArgumentType)
{
WasCompilerGenerated = true
};
var paramCount = method.ParameterCount;
var arguments = new BoundExpression[paramCount];
var argumentTypes = new TypeSymbol[paramCount];
for (int i = 0; i < paramCount; i++)
{
var argument = (i == 0) ? thisArgumentValue : otherArgumentValue;
arguments[i] = argument;
argumentTypes[i] = argument.Type;
}
var typeArgs = MethodTypeInferrer.InferTypeArgumentsFromFirstArgument(
conversions,
method,
argumentTypes.AsImmutableOrNull(),
arguments.AsImmutableOrNull(),
ref useSiteDiagnostics);
if (typeArgs.IsDefault)
{
return(null);
}
// Check constraints.
var diagnosticsBuilder = ArrayBuilder <TypeParameterDiagnosticInfo> .GetInstance();
var typeParams = method.TypeParameters;
var substitution = new TypeMap(typeParams, typeArgs);
ArrayBuilder <TypeParameterDiagnosticInfo> useSiteDiagnosticsBuilder = null;
var success = method.CheckConstraints(conversions, substitution, method.TypeParameters, typeArgs, compilation, diagnosticsBuilder, ref useSiteDiagnosticsBuilder);
diagnosticsBuilder.Free();
if (useSiteDiagnosticsBuilder != null && useSiteDiagnosticsBuilder.Count > 0)
{
if (useSiteDiagnostics == null)
{
useSiteDiagnostics = new HashSet <DiagnosticInfo>();
}
foreach (var diag in useSiteDiagnosticsBuilder)
{
useSiteDiagnostics.Add(diag.DiagnosticInfo);
}
}
if (!success)
{
return(null);
}
return(method.Construct(typeArgs));
}
