36public static NullableFlowState GetNullableState(ArrayBuilder<TypeWithState> types) 38NullableFlowState result = NullableFlowState.NotNull;

466SetState(ref State, outputSlot, NullableFlowState.NotNull); 518SetState(ref this.State, outputSlot, NullableFlowState.NotNull); // Slice value is assumed to be never null 526var inputState = GetState(ref this.State, inputSlot); 631var tempState = GetState(ref this.State, tempSlot); 999receiverType: TypeWithState.Create(inputType, NullableFlowState.NotNull), 1150NullableFlowState inferredState; 1200NullableFlowState inferredState = BestTypeInferrer.GetNullableState(resultTypes);

145public VisitResult(TypeSymbol? type, NullableAnnotation annotation, NullableFlowState state) 235private static readonly TypeWithState _invalidType = TypeWithState.Create(new UnsupportedMetadataTypeSymbol(), NullableFlowState.NotNull); 838var memberState = GetState(ref state, slot); 839var badState = symbolType.Type.IsPossiblyNullableReferenceTypeTypeParameter() && (annotations & FlowAnalysisAnnotations.NotNull) == 0 840? NullableFlowState.MaybeDefault 841: NullableFlowState.MaybeNull; 897SetState(ref this.State, memberSlot, type.Type.IsPossiblyNullableReferenceTypeTypeParameter() ? NullableFlowState.MaybeDefault : NullableFlowState.MaybeNull); 1192var parameterState = GetState(ref state, memberSlot); 1224SetState(ref this.State, memberSlot, NullableFlowState.MaybeNull); 1337var parameterState = GetState(ref state, slot); 1393var parameterState = GetState(ref stateWhen, slot); 1420private void EnforceNotNullIfNotNull(SyntaxNode? syntaxOpt, LocalState state, ImmutableArray<ParameterSymbol> parameters, ImmutableHashSet<string> inputParamNames, NullableFlowState outputState, ParameterSymbol? outputParam) 2008private NullableFlowState GetState(ref LocalState state, int slot) 2011return NullableFlowState.NotNull; 2017private void SetState(ref LocalState state, int slot, NullableFlowState value, bool useNotNullsAsDefault = false) 2039private NullableFlowState GetDefaultState(ref LocalState state, int slot) 2044return NullableFlowState.NotNull; 2080return NullableFlowState.NotNull; 2409private static bool ShouldReportNullableAssignment(TypeWithAnnotations type, NullableFlowState state) 2426case NullableFlowState.NotNull: 2428case NullableFlowState.MaybeNull: 2504valueType.State == NullableFlowState.MaybeDefault; 2686var newState = valueType.State; 2797NullableFlowState value = isDefaultValue ? NullableFlowState.MaybeNull : fieldOrPropertyType.ToTypeWithState().State; 2809NullableFlowState.NotNull; 2857/// and the new state is not <see cref="NullableFlowState.NotNull"/>, this method should be called to perform the 2861private void SetStateAndTrackForFinally(ref LocalState state, int slot, NullableFlowState newState) 2865if (newState != NullableFlowState.NotNull && NonMonotonicState.HasValue) 2950private NullableFlowState GetDefaultState(Symbol symbol) 3043var state = GetParameterState(parameterType, parameter.FlowAnalysisAnnotations).State; 3081return TypeWithState.Create(parameterType.Type, NullableFlowState.MaybeDefault); 3086return TypeWithState.Create(parameterType.Type, NullableFlowState.NotNull); 3389SetState(ref state, slot, NullableFlowState.NotNull); 3662placeholderResult = new VisitResult(placeholder.Type, NullableAnnotation.NotAnnotated, NullableFlowState.NotNull); 3913SetResultType(node, TypeWithState.Create(null, NullableFlowState.NotNull)); 3921SetResultType(node, TypeWithState.Create(null, NullableFlowState.NotNull)); 4017NullableFlowState.NotNull)); 4199NullableFlowState resultState = getResultState(node, collectionKind); 4215static NullableFlowState getResultState(BoundCollectionExpression node, CollectionExpressionTypeKind collectionKind) 4227return NullableFlowState.NotNull; 4297(int slot, NullableFlowState resultState, Func<TypeSymbol, MethodSymbol?, int>? initialStateInferenceCompletion) = 4317NullableFlowState resultState, 4346NullableFlowState resultState) 4348Debug.Assert(resultState == NullableFlowState.NotNull); 4380(int slot, NullableFlowState resultState, Func<TypeSymbol, MethodSymbol?, int>? completion) inferInitialObjectState( 4388return (-1, NullableFlowState.NotNull, inferInitialObjectStateAsContinuation(node, arguments, argumentResults, hasObjectInitializer)); 4394var resultState = NullableFlowState.NotNull; 4426resultState = NullableFlowState.MaybeNull; 4483Debug.Assert(resultState == NullableFlowState.NotNull); 4492NullableFlowState operandState; 4636var result = new VisitResult(objectInitializer.Type, NullableAnnotation.NotAnnotated, NullableFlowState.NotNull); 4661argumentResults = argumentResults.SetItem(0, new VisitResult(containingType, NullableAnnotation.NotAnnotated, NullableFlowState.NotNull)); 4787firstArgumentResult = new VisitResult(containingType, NullableAnnotation.NotAnnotated, NullableFlowState.NotNull); 4880SetAnalyzedNullability(node.ImplicitReceiverOpt, new VisitResult(node.ImplicitReceiverOpt.Type, NullableAnnotation.NotAnnotated, NullableFlowState.NotNull)); 4938SetResultType(node, TypeWithState.Create(node.Type, NullableFlowState.NotNull)); 4943var resultType = TypeWithState.Create(node.Type, NullableFlowState.NotNull); 5051SetResultType(node, TypeWithState.Create(anonymousType, NullableFlowState.NotNull)); 5083SetResultType(node, TypeWithState.Create(node.Type, NullableFlowState.NotNull)); 5088SetResultType(node, TypeWithState.Create(arrayType, NullableFlowState.NotNull)); 5164var elementState = BestTypeInferrer.GetNullableState(expressionTypes); 5366NullableFlowState resultState = NullableFlowState.NotNull; 5394resultState = NullableFlowState.MaybeNull; // Delegate removal can produce null. 5397resultState = NullableFlowState.NotNull; 5986SetState(ref stateToUpdate, slot, NullableFlowState.NotNull); 6015SetState(ref state, slot, NullableFlowState.NotNull); 6040if (GetState(ref state, slot) == NullableFlowState.NotNull) 6043SetState(ref state, slot, NullableFlowState.MaybeNull); 6072SetState(ref state, childSlot, NullableFlowState.NotNull); 6151SetState(ref this.State, leftSlot, NullableFlowState.NotNull); 6206BoundNullCoalescingOperatorResultKind.NoCommonType => (node.Type, NullableFlowState.NotNull), 6211BoundNullCoalescingOperatorResultKind.RightDynamicType => (rightResultType!, NullableFlowState.NotNull), 6218(TypeSymbol ResultType, NullableFlowState LeftState) getLeftResultType(TypeSymbol leftType, TypeSymbol rightType) 6229return (rightType, NullableFlowState.NotNull); 6235return (leftType, NullableFlowState.NotNull); 6238(TypeSymbol ResultType, NullableFlowState LeftState) getResultStateWithRightType(TypeSymbol leftType, TypeSymbol rightType) 6250TypeWithState.Create(leftType, NullableFlowState.NotNull), 6261return (rightType, NullableFlowState.NotNull); 6434SetResultType(node, TypeWithState.Create(resultType, NullableFlowState.MaybeDefault)); 6489var rValueState = consequenceRValue.State.Join(alternativeRValue.State); 6597NullableFlowState resultState; 6757SetResultType(node, TypeWithState.Create(rvalueType, NullableFlowState.NotNull)); 7295private NullableFlowState LearnFromCompareExchangeMethod(in CompareExchangeInfo compareExchangeInfo) 7315return NullableFlowState.NotNull; 7325var valueFlowState = compareExchangeInfo.Results[valueIndex].RValueType.State; 7332var locationFlowState = compareExchangeInfo.Results[locationIndex].RValueType.State; 7449return TypeWithState.Create(typeWithState.Type, NullableFlowState.NotNull); 7454return TypeWithState.Create(typeWithState.Type, NullableFlowState.MaybeDefault); 8071SetState(ref state, memberSlot, NullableFlowState.NotNull); 8373var adjustedState = LearnFromCompareExchangeMethod(in compareExchangeInfoOpt); 8516return TypeWithState.Create(typeWithState.Type, NullableFlowState.MaybeDefault); 8522return TypeWithState.Create(typeWithState.Type, NullableFlowState.NotNull); 8537return TypeWithState.Create(typeWithState.Type, NullableFlowState.MaybeDefault); 8541return TypeWithState.Create(typeWithState.Type, NullableFlowState.NotNull); 8556return TypeWithState.Create(typeWithState.Type, NullableFlowState.MaybeDefault); 8560return TypeWithState.Create(typeWithState.Type, NullableFlowState.NotNull); 9129NullableFlowState state = GetState(ref this.State, slot); 9404SetResultType(node, TypeWithState.Create(null, NullableFlowState.NotNull)); 9411SetState(ref this.State, slot, NullableFlowState.NotNull); 9429SetResultType(node, TypeWithState.Create(tupleOpt, NullableFlowState.NotNull)); 9552SetState(ref this.State, targetFieldSlot, NullableFlowState.NotNull); 9569SetState(ref this.State, targetFieldSlot, NullableFlowState.NotNull); 9864NullableFlowState resultState = NullableFlowState.NotNull; 9896resultState = NullableFlowState.NotNull; 9921return TypeWithState.Create(targetType, NullableFlowState.NotNull); 9927resultState = NullableFlowState.NotNull; 9931resultState = NullableFlowState.NotNull; 9936resultState = NullableFlowState.NotNull; 9996resultState = NullableFlowState.NotNull; 10158resultState = NullableFlowState.NotNull; 10227static TypeWithState calculateResultType(TypeWithAnnotations targetTypeWithNullability, bool fromExplicitCast, NullableFlowState resultState, bool isSuppressed, TypeSymbol targetType) 10231resultState = NullableFlowState.NotNull; 10236resultState = targetType?.IsTypeParameterDisallowingAnnotationInCSharp8() == true ? NullableFlowState.MaybeDefault : NullableFlowState.MaybeNull; 10243static NullableFlowState getReferenceConversionResultState(TypeWithAnnotations targetType, TypeWithState operandType) 10245var state = operandType.State; 10248case NullableFlowState.MaybeNull: 10254return NullableFlowState.MaybeDefault; 10260return (annotation == NullableAnnotation.Annotated) ? NullableFlowState.MaybeDefault : NullableFlowState.MaybeNull; 10264case NullableFlowState.MaybeDefault: 10267return NullableFlowState.MaybeNull; 10277static NullableFlowState getBoxingConversionResultState(TypeWithAnnotations targetType, TypeWithState operandType) 10279var state = operandType.State; 10280if (state == NullableFlowState.MaybeNull) 10285return NullableFlowState.MaybeDefault; 10295return (annotation == NullableAnnotation.Annotated) ? NullableFlowState.MaybeDefault : NullableFlowState.MaybeNull; 10305static NullableFlowState getUnboxingConversionResultState(TypeWithState operandType) 10307var state = operandType.State; 10308if (state == NullableFlowState.MaybeNull) 10310return NullableFlowState.MaybeDefault; 10315static NullableFlowState getConversionResultState(TypeWithState operandType) 10317var state = operandType.State; 10318if (state == NullableFlowState.MaybeNull) 10320return NullableFlowState.MaybeDefault; 10455var resultType = TypeWithState.Create(targetType, NullableFlowState.NotNull); 10498NullableFlowState operandState = operandType.State; 10563private TypeWithState GetConversionReturnTypeWithState(MethodSymbol method, bool isLiftedConversion, NullableFlowState operandState) 10607var resultType = TypeWithState.Create(targetTypeWithNullability.Type, NullableFlowState.NotNull); 10700unionTypeWithState = TypeWithState.Create(toType, NullableFlowState.NotNull); 10794private TypeWithState GetLiftedReturnType(TypeWithAnnotations returnType, NullableFlowState operandState) 10798NullableFlowState state = returnType.ToTypeWithState().State.Join(operandState); 10815private TypeWithState GetLiftedReturnTypeIfNecessary(bool isLifted, TypeWithAnnotations returnType, NullableFlowState operandState) 10911var result = TypeWithState.Create(delegateType, NullableFlowState.NotNull); 11208var rvalueResult = TypeWithState.Create(node.Type, NullableFlowState.NotNull); 11626var valueBeforeNullableWrapping = TypeWithState.Create(underlyingType.Type, NullableFlowState.NotNull); 11759SetResultType(node, TypeWithState.Create(receiverType.Type, NullableFlowState.NotNull)); 11783SetResultType(node, TypeWithState.Create(opType.Type, NullableFlowState.NotNull)); 11952SetResultType(node, TypeWithState.Create(receiverType.Type, NullableFlowState.NotNull)); 11980SetResultType(node, TypeWithState.Create(opType.Type, NullableFlowState.NotNull)); 12339var state = GetState(ref this.State, slot); 12361SetState(ref this.StateWhenTrue, slotToSet, NullableFlowState.NotNull); 12592if (enumeratorReturnType.State != NullableFlowState.NotNull) 12663var state = NullableFlowState.NotNull; 12867TypeWithState.Create(node.Type, node.OperatorKind.IsLifted() ? argumentResult.State : NullableFlowState.NotNull); 13133SetResultType(node, TypeWithState.Create(node.Type, NullableFlowState.NotNull)); 13155SetResultType(node, TypeWithState.Create(node.Type, NullableFlowState.MaybeDefault)); 13170SetState(ref this.State, slot, NullableFlowState.NotNull); 13216NullableFlowState resultState = NullableFlowState.NotNull; 13231resultState = NullableFlowState.MaybeDefault; 13269SetResultType(node, TypeWithState.Create(node.Type, node.Type?.CanContainNull() != false && node.ConstantValueOpt?.IsNull == true ? NullableFlowState.MaybeDefault : NullableFlowState.NotNull)); 13377node.IsAddition ? GetState(ref this.State, memberSlot).Meet(ResultType.State) : NullableFlowState.MaybeNull); 13494private bool ReportPossibleNullReceiverIfNeeded(TypeSymbol type, NullableFlowState state, bool checkNullableValueType, SyntaxNode syntax, out bool reportedDiagnostic) 13553SetResultType(node, TypeWithState.Create(node.Type, NullableFlowState.NotNull)); 13568SetResultType(node, TypeWithState.Create(node.Type, NullableFlowState.NotNull)); 13617SetResultType(node, TypeWithState.Create(node.Type, NullableFlowState.NotNull)); 13623SetResultType(node, TypeWithState.Create(type, NullableFlowState.NotNull)); 13691SetState(ref this.State, slot, NullableFlowState.NotNull); 13833Debug.Assert(ResultType is TypeWithState { Type: FunctionPointerTypeSymbol { }, State: NullableFlowState.NotNull }); 14139SetValue(Id, index, useNotNullsAsDefault ? NullableFlowState.NotNull : walker.GetDefaultState(ref this, slot)); 14143public NullableFlowState this[int slot] 14157private NullableFlowState GetValue(int id, int index) 14167private NullableFlowState GetValue(int index) 14171return NullableFlowState.NotNull; 14178var result = (_state[index], _state[index + 1]) switch 14180(false, false) => NullableFlowState.NotNull, // Should not be reachable 14181(true, false) => NullableFlowState.MaybeNull, 14182(false, true) => NullableFlowState.MaybeDefault, 14183(true, true) => NullableFlowState.NotNull 14189private void SetValue(int id, int index, NullableFlowState value) 14202private void SetValue(int index, NullableFlowState value) 14210NullableFlowState.MaybeNull => (true, false), 14211NullableFlowState.MaybeDefault => (false, true), 14212NullableFlowState.NotNull => (true, true), 14266var oldValue = oldReachable ? GetValue(i) : NullableFlowState.NotNull; 14267var newValue = oldValue.Join(other.GetValue(i)); 14292var oldValue = GetValue(i); 14293var newValue = oldValue.Meet(other.GetValue(i)); 14309var mayBeNull = GetValue(i) is NullableFlowState.MaybeNull or NullableFlowState.MaybeDefault; 14340NullableFlowState.MaybeNull => "?", 14341NullableFlowState.MaybeDefault => "??",

1226static NullableFlowState getTypeArgumentState(in TypeWithAnnotations typeWithAnnotations) 1231return NullableFlowState.NotNull; 1235return type.IsNullableTypeOrTypeParameter() ? NullableFlowState.MaybeNull : NullableFlowState.NotNull; 1240return type.IsTypeParameterDisallowingAnnotationInCSharp8() ? NullableFlowState.MaybeDefault : NullableFlowState.MaybeNull; 1242return NullableFlowState.NotNull; 1247return NullableFlowState.NotNull; 1249NullableFlowState? result = null; 1252var constraintState = getTypeArgumentState(constraintType); 1262return result ?? NullableFlowState.MaybeNull; 1265static bool constraintTypeAllows(in TypeWithAnnotations typeWithAnnotations, NullableFlowState state) 1267if (state == NullableFlowState.NotNull) 1294return state == NullableFlowState.MaybeNull;

46public StrongBox<NullableFlowState>? _lazyValueDeclaredNullableFlowState; 2674internal NullableFlowState UnionValueDeclaredNullableFlowState 2679StrongBox<NullableFlowState>? lazyNullableFlowState = lazyUnionData._lazyValueDeclaredNullableFlowState; 2687var result = NullableFlowState.NotNull; 2696lazyUnionData._lazyValueDeclaredNullableFlowState = new StrongBox<NullableFlowState>(result);

104var flowState = TypeWithAnnotations.Create(type, annotation).ToTypeWithState().State;

11/// When in doubt we conservatively use <see cref="NullableFlowState.NotNull"/>

13public static bool MayBeNull(this NullableFlowState state) => state != NullableFlowState.NotNull; 15public static bool IsNotNull(this NullableFlowState state) => state == NullableFlowState.NotNull; 19/// The result is <see cref="NullableFlowState.MaybeNull"/> if either operand is that. 21public static NullableFlowState Join(this NullableFlowState a, NullableFlowState b) => (a > b) ? a : b; 25/// The result is <see cref="NullableFlowState.NotNull"/> if either operand is that. 27public static NullableFlowState Meet(this NullableFlowState a, NullableFlowState b) => (a < b) ? a : b; 29internal static CodeAnalysis.NullableFlowState ToPublicFlowState(this CSharp.NullableFlowState nullableFlowState) => 32CSharp.NullableFlowState.NotNull => CodeAnalysis.NullableFlowState.NotNull, 33CSharp.NullableFlowState.MaybeNull => CodeAnalysis.NullableFlowState.MaybeNull, 34CSharp.NullableFlowState.MaybeDefault => CodeAnalysis.NullableFlowState.MaybeNull, 39public static CSharp.NullableFlowState ToInternalFlowState(this CodeAnalysis.NullableFlowState flowState) => 42CodeAnalysis.NullableFlowState.None => CSharp.NullableFlowState.NotNull, 43CodeAnalysis.NullableFlowState.NotNull => CSharp.NullableFlowState.NotNull, 44CodeAnalysis.NullableFlowState.MaybeNull => CSharp.NullableFlowState.MaybeNull,

813static NullableFlowState getFlowState(TypeSymbol type, NullableAnnotation annotation) 817return annotation.IsAnnotated() ? NullableFlowState.MaybeDefault : NullableFlowState.NotNull; 821return annotation switch { NullableAnnotation.Annotated => NullableFlowState.MaybeDefault, NullableAnnotation.NotAnnotated => NullableFlowState.MaybeNull, _ => NullableFlowState.NotNull }; 825return annotation switch { NullableAnnotation.Annotated => NullableFlowState.MaybeDefault, _ => NullableFlowState.NotNull }; 829return NullableFlowState.MaybeNull; 831return annotation switch { NullableAnnotation.Annotated => NullableFlowState.MaybeNull, _ => NullableFlowState.NotNull };

17public readonly NullableFlowState State; 20public bool MayBeNull => State == NullableFlowState.MaybeNull; 21public bool IsNotNull => State == NullableFlowState.NotNull; 25return Create(type, NullableFlowState.MaybeDefault); 28public static TypeWithState Create(TypeSymbol? type, NullableFlowState defaultState) 30if (defaultState == NullableFlowState.MaybeDefault && 36var state = defaultState != NullableFlowState.NotNull && type?.CanContainNull() != false ? NullableFlowState.MaybeNull : NullableFlowState.NotNull; 45NullableFlowState state; 50state = NullableFlowState.MaybeDefault; 54state = NullableFlowState.NotNull; 63state = NullableFlowState.NotNull; 69private TypeWithState(TypeSymbol? type, NullableFlowState state) 71Debug.Assert(state == NullableFlowState.NotNull || type?.CanContainNull() != false); 72Debug.Assert(state != NullableFlowState.MaybeDefault || type is null || type.IsTypeParameterDisallowingAnnotationInCSharp8()); 81public TypeWithState WithNotNullState() => new TypeWithState(Type, NullableFlowState.NotNull); 83public TypeWithState WithSuppression(bool suppress) => suppress ? new TypeWithState(Type, NullableFlowState.NotNull) : this; 90return (State == NullableFlowState.MaybeDefault || asAnnotatedType) ? type.SetIsAnnotated(compilation) : type;