Merge pull request #3017 from icsharpcode/operator-checked

ICSharpCode.Decompiler.Tests/TestCases/Pretty/Operators.cs

@@ -42,6 +42,28 @@ namespace ICSharpCode.Decompiler.Tests.TestCases.Pretty
 			return null;
 		}
 
+#if CS110
+		public static AllOperators operator checked +(AllOperators a, AllOperators b)
+		{
+			return null;
+		}
+
+		public static AllOperators operator checked -(AllOperators a, AllOperators b)
+		{
+			return null;
+		}
+
+		public static AllOperators operator checked *(AllOperators a, AllOperators b)
+		{
+			return null;
+		}
+
+		public static AllOperators operator checked /(AllOperators a, AllOperators b)
+		{
+			return null;
+		}
+#endif
+
 		public static AllOperators operator %(AllOperators a, AllOperators b)
 		{
 			return null;
@@ -109,6 +131,23 @@ namespace ICSharpCode.Decompiler.Tests.TestCases.Pretty
 			return null;
 		}
 
+#if CS110
+		public static AllOperators operator checked -(AllOperators a)
+		{
+			return null;
+		}
+
+		public static AllOperators operator checked ++(AllOperators a)
+		{
+			return null;
+		}
+
+		public static AllOperators operator checked --(AllOperators a)
+		{
+			return null;
+		}
+#endif
+
 		public static bool operator true(AllOperators a)
 		{
 			return false;
@@ -158,6 +197,13 @@ namespace ICSharpCode.Decompiler.Tests.TestCases.Pretty
 		{
 			return 0;
 		}
+
+#if CS110
+		public static explicit operator checked int(AllOperators a)
+		{
+			return 0;
+		}
+#endif
 	}
 
 	public class UseAllOperators
@@ -171,6 +217,18 @@ namespace ICSharpCode.Decompiler.Tests.TestCases.Pretty
 			c = a - b;
 			c = a * b;
 			c = a / b;
+#if CS110
+			checked
+			{
+				c = a + b;
+				c = a - b;
+				c = a * b;
+				c = a / b;
+			}
+			// force end of checked block:
+			++a;
+#endif
+
 			c = a % b;
 			c = a & b;
 			c = a | b;
@@ -186,6 +244,16 @@ namespace ICSharpCode.Decompiler.Tests.TestCases.Pretty
 			c = +a;
 			c = ++a;
 			c = --a;
+#if CS110
+			checked
+			{
+				c = -a;
+				c = ++a;
+				c = --a;
+			}
+			// force end of checked block:
+			++a;
+#endif
 			if (a)
 			{
 				Console.WriteLine("a");
@@ -219,6 +287,11 @@ namespace ICSharpCode.Decompiler.Tests.TestCases.Pretty
 				Console.WriteLine("a >= b");
 			}
 			int num = (int)a;
+#if CS110
+			num = checked((int)a);
+			// force end of checked block:
+			num = (int)a;
+#endif
 			a = num;
 		}
 	}

ICSharpCode.Decompiler/CSharp/CSharpDecompiler.cs

@@ -531,6 +531,7 @@ namespace ICSharpCode.Decompiler.CSharp
 			typeSystemAstBuilder.SupportRecordClasses = settings.RecordClasses;
 			typeSystemAstBuilder.SupportRecordStructs = settings.RecordStructs;
 			typeSystemAstBuilder.SupportUnsignedRightShift = settings.UnsignedRightShift;
+			typeSystemAstBuilder.SupportOperatorChecked = settings.CheckedOperators;
 			typeSystemAstBuilder.AlwaysUseGlobal = settings.AlwaysUseGlobal;
 			return typeSystemAstBuilder;
 		}

ICSharpCode.Decompiler/CSharp/ExpressionBuilder.cs

@@ -1810,6 +1810,15 @@ namespace ICSharpCode.Decompiler.CSharp
 			{
 				target = Translate(inst.Target, loadType);
 			}
+			var opType = OperatorDeclaration.GetOperatorType(inst.Method.Name);
+			if (opType != null && OperatorDeclaration.IsChecked(opType.Value))
+			{
+				target.Expression.AddAnnotation(AddCheckedBlocks.CheckedAnnotation);
+			}
+			else if (ReplaceMethodCallsWithOperators.HasCheckedEquivalent(inst.Method))
+			{
+				target.Expression.AddAnnotation(AddCheckedBlocks.UncheckedAnnotation);
+			}
 			if (UserDefinedCompoundAssign.IsStringConcat(inst.Method))
 			{
 				Debug.Assert(inst.Method.Parameters.Count == 2);
@@ -1876,8 +1885,10 @@ namespace ICSharpCode.Decompiler.CSharp
 			switch (name)
 			{
 				case "op_Increment":
+				case "op_CheckedIncrement":
 					return isPostfix ? UnaryOperatorType.PostIncrement : UnaryOperatorType.Increment;
 				case "op_Decrement":
+				case "op_CheckedDecrement":
 					return isPostfix ? UnaryOperatorType.PostDecrement : UnaryOperatorType.Decrement;
 				default:
 					return null;

ICSharpCode.Decompiler/CSharp/OutputVisitor/CSharpAmbience.cs

@@ -238,6 +238,7 @@ namespace ICSharpCode.Decompiler.CSharp.OutputVisitor
 			astBuilder.SupportRecordClasses = (ConversionFlags & ConversionFlags.SupportRecordClasses) != 0;
 			astBuilder.SupportRecordStructs = (ConversionFlags & ConversionFlags.SupportRecordStructs) != 0;
 			astBuilder.SupportUnsignedRightShift = (ConversionFlags & ConversionFlags.SupportUnsignedRightShift) != 0;
+			astBuilder.SupportOperatorChecked = (ConversionFlags & ConversionFlags.SupportOperatorChecked) != 0;
 			return astBuilder;
 		}
 
@@ -296,20 +297,35 @@ namespace ICSharpCode.Decompiler.CSharp.OutputVisitor
 							ConvertType(member.ReturnType, writer, formattingPolicy);
 							break;
 						case "op_Explicit":
+						case "op_CheckedExplicit":
 							writer.WriteKeyword(OperatorDeclaration.ExplicitRole, "explicit");
 							writer.Space();
 							writer.WriteKeyword(OperatorDeclaration.OperatorKeywordRole, "operator");
 							writer.Space();
+							if (member.Name == "op_CheckedExplicit")
+							{
+								writer.WriteToken(OperatorDeclaration.CheckedKeywordRole, "checked");
+								writer.Space();
+							}
 							ConvertType(member.ReturnType, writer, formattingPolicy);
 							break;
 						default:
 							writer.WriteKeyword(OperatorDeclaration.OperatorKeywordRole, "operator");
 							writer.Space();
 							var operatorType = OperatorDeclaration.GetOperatorType(member.Name);
-							if (operatorType.HasValue)
+							if (operatorType.HasValue && !((ConversionFlags & ConversionFlags.SupportOperatorChecked) == 0 && OperatorDeclaration.IsChecked(operatorType.Value)))
+							{
+								if (OperatorDeclaration.IsChecked(operatorType.Value))
+								{
+									writer.WriteToken(OperatorDeclaration.CheckedKeywordRole, "checked");
+									writer.Space();
+								}
 								writer.WriteToken(OperatorDeclaration.GetRole(operatorType.Value), OperatorDeclaration.GetToken(operatorType.Value));
+							}
 							else
+							{
 								writer.WriteIdentifier(node.NameToken);
+							}
 							break;
 					}
 					break;

ICSharpCode.Decompiler/CSharp/OutputVisitor/CSharpOutputVisitor.cs

@@ -2528,7 +2528,7 @@ namespace ICSharpCode.Decompiler.CSharp.OutputVisitor
 			StartNode(operatorDeclaration);
 			WriteAttributes(operatorDeclaration.Attributes);
 			WriteModifiers(operatorDeclaration.ModifierTokens);
-			if (operatorDeclaration.OperatorType == OperatorType.Explicit)
+			if (operatorDeclaration.OperatorType == OperatorType.Explicit || operatorDeclaration.OperatorType == OperatorType.CheckedExplicit)
 			{
 				WriteKeyword(OperatorDeclaration.ExplicitRole);
 			}
@@ -2542,7 +2542,13 @@ namespace ICSharpCode.Decompiler.CSharp.OutputVisitor
 			}
 			WriteKeyword(OperatorDeclaration.OperatorKeywordRole);
 			Space();
+			if (OperatorDeclaration.IsChecked(operatorDeclaration.OperatorType))
+			{
+				WriteKeyword(OperatorDeclaration.CheckedKeywordRole);
+				Space();
+			}
 			if (operatorDeclaration.OperatorType == OperatorType.Explicit
+				|| operatorDeclaration.OperatorType == OperatorType.CheckedExplicit
 				|| operatorDeclaration.OperatorType == OperatorType.Implicit)
 			{
 				operatorDeclaration.ReturnType.AcceptVisitor(this);
@@ -3082,7 +3088,7 @@ namespace ICSharpCode.Decompiler.CSharp.OutputVisitor
 					break;
 				case SymbolKind.Operator:
 					var opType = documentationReference.OperatorType;
-					if (opType == OperatorType.Explicit)
+					if (opType == OperatorType.Explicit || opType == OperatorType.CheckedExplicit)
 					{
 						WriteKeyword(OperatorDeclaration.ExplicitRole);
 					}
@@ -3092,7 +3098,12 @@ namespace ICSharpCode.Decompiler.CSharp.OutputVisitor
 					}
 					WriteKeyword(OperatorDeclaration.OperatorKeywordRole);
 					Space();
-					if (opType == OperatorType.Explicit || opType == OperatorType.Implicit)
+					if (OperatorDeclaration.IsChecked(opType))
+					{
+						WriteKeyword(OperatorDeclaration.CheckedKeywordRole);
+						Space();
+					}
+					if (opType == OperatorType.Explicit || opType == OperatorType.Implicit || opType == OperatorType.CheckedExplicit)
 					{
 						documentationReference.ConversionOperatorReturnType.AcceptVisitor(this);
 					}

ICSharpCode.Decompiler/CSharp/Syntax/TypeMembers/OperatorDeclaration.cs

@@ -37,20 +37,25 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 		LogicalNot,
 		OnesComplement,
 		Increment,
+		CheckedIncrement,
 		Decrement,
+		CheckedDecrement,
 		True,
 		False,
 
-		// Unary and Binary operators
-		Addition,
-		Subtraction,
-
 		UnaryPlus,
 		UnaryNegation,
+		CheckedUnaryNegation,
 
 		// Binary operators
+		Addition,
+		CheckedAddition,
+		Subtraction,
+		CheckedSubtraction,
 		Multiply,
+		CheckedMultiply,
 		Division,
+		CheckedDivision,
 		Modulus,
 		BitwiseAnd,
 		BitwiseOr,
@@ -67,12 +72,14 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 
 		// Implicit and Explicit
 		Implicit,
-		Explicit
+		Explicit,
+		CheckedExplicit
 	}
 
 	public class OperatorDeclaration : EntityDeclaration
 	{
 		public static readonly TokenRole OperatorKeywordRole = new TokenRole("operator");
+		public static readonly TokenRole CheckedKeywordRole = new TokenRole("checked");
 
 		// Unary operators
 		public static readonly TokenRole LogicalNotRole = new TokenRole("!");
@@ -110,19 +117,26 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 
 		static OperatorDeclaration()
 		{
-			names = new string[(int)OperatorType.Explicit + 1][];
+			names = new string[(int)OperatorType.CheckedExplicit + 1][];
 			names[(int)OperatorType.LogicalNot] = new string[] { "!", "op_LogicalNot" };
 			names[(int)OperatorType.OnesComplement] = new string[] { "~", "op_OnesComplement" };
 			names[(int)OperatorType.Increment] = new string[] { "++", "op_Increment" };
+			names[(int)OperatorType.CheckedIncrement] = new string[] { "++", "op_CheckedIncrement" };
 			names[(int)OperatorType.Decrement] = new string[] { "--", "op_Decrement" };
+			names[(int)OperatorType.CheckedDecrement] = new string[] { "--", "op_CheckedDecrement" };
 			names[(int)OperatorType.True] = new string[] { "true", "op_True" };
 			names[(int)OperatorType.False] = new string[] { "false", "op_False" };
-			names[(int)OperatorType.Addition] = new string[] { "+", "op_Addition" };
-			names[(int)OperatorType.Subtraction] = new string[] { "-", "op_Subtraction" };
 			names[(int)OperatorType.UnaryPlus] = new string[] { "+", "op_UnaryPlus" };
 			names[(int)OperatorType.UnaryNegation] = new string[] { "-", "op_UnaryNegation" };
+			names[(int)OperatorType.CheckedUnaryNegation] = new string[] { "-", "op_CheckedUnaryNegation" };
+			names[(int)OperatorType.Addition] = new string[] { "+", "op_Addition" };
+			names[(int)OperatorType.CheckedAddition] = new string[] { "+", "op_CheckedAddition" };
+			names[(int)OperatorType.Subtraction] = new string[] { "-", "op_Subtraction" };
+			names[(int)OperatorType.CheckedSubtraction] = new string[] { "-", "op_CheckedSubtraction" };
 			names[(int)OperatorType.Multiply] = new string[] { "*", "op_Multiply" };
+			names[(int)OperatorType.CheckedMultiply] = new string[] { "*", "op_CheckedMultiply" };
 			names[(int)OperatorType.Division] = new string[] { "/", "op_Division" };
+			names[(int)OperatorType.CheckedDivision] = new string[] { "/", "op_CheckedDivision" };
 			names[(int)OperatorType.Modulus] = new string[] { "%", "op_Modulus" };
 			names[(int)OperatorType.BitwiseAnd] = new string[] { "&", "op_BitwiseAnd" };
 			names[(int)OperatorType.BitwiseOr] = new string[] { "|", "op_BitwiseOr" };
@@ -138,6 +152,7 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 			names[(int)OperatorType.LessThanOrEqual] = new string[] { "<=", "op_LessThanOrEqual" };
 			names[(int)OperatorType.Implicit] = new string[] { "implicit", "op_Implicit" };
 			names[(int)OperatorType.Explicit] = new string[] { "explicit", "op_Explicit" };
+			names[(int)OperatorType.CheckedExplicit] = new string[] { "explicit", "op_CheckedExplicit" };
 		}
 
 		public override SymbolKind SymbolKind {
@@ -202,8 +217,10 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 				case OperatorType.OnesComplement:
 					return OnesComplementRole;
 				case OperatorType.Increment:
+				case OperatorType.CheckedIncrement:
 					return IncrementRole;
 				case OperatorType.Decrement:
+				case OperatorType.CheckedDecrement:
 					return DecrementRole;
 				case OperatorType.True:
 					return TrueRole;
@@ -211,15 +228,20 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 					return FalseRole;
 
 				case OperatorType.Addition:
+				case OperatorType.CheckedAddition:
 				case OperatorType.UnaryPlus:
 					return AdditionRole;
 				case OperatorType.Subtraction:
+				case OperatorType.CheckedSubtraction:
 				case OperatorType.UnaryNegation:
+				case OperatorType.CheckedUnaryNegation:
 					return SubtractionRole;
 
 				case OperatorType.Multiply:
+				case OperatorType.CheckedMultiply:
 					return MultiplyRole;
 				case OperatorType.Division:
+				case OperatorType.CheckedDivision:
 					return DivisionRole;
 				case OperatorType.Modulus:
 					return ModulusRole;
@@ -251,6 +273,7 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 				case OperatorType.Implicit:
 					return ImplicitRole;
 				case OperatorType.Explicit:
+				case OperatorType.CheckedExplicit:
 					return ExplicitRole;
 
 				default:
@@ -269,7 +292,26 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 		}
 
 		/// <summary>
-		/// Gets the token for the operator type ("+", "implicit", etc.)
+		/// Gets whether the operator type is a C# 11 "operator checked".
+		/// </summary>
+		public static bool IsChecked(OperatorType type)
+		{
+			return type switch {
+				OperatorType.CheckedAddition => true,
+				OperatorType.CheckedSubtraction => true,
+				OperatorType.CheckedMultiply => true,
+				OperatorType.CheckedDivision => true,
+				OperatorType.CheckedUnaryNegation => true,
+				OperatorType.CheckedIncrement => true,
+				OperatorType.CheckedDecrement => true,
+				OperatorType.CheckedExplicit => true,
+				_ => false,
+			};
+		}
+
+		/// <summary>
+		/// Gets the token for the operator type ("+", "implicit", etc.).
+		/// Does not include the "checked" modifier.
 		/// </summary>
 		public static string GetToken(OperatorType type)
 		{

ICSharpCode.Decompiler/CSharp/Syntax/TypeSystemAstBuilder.cs

@@ -230,6 +230,11 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 		/// </summary>
 		public bool SupportUnsignedRightShift { get; set; }
 
+		/// <summary>
+		/// Controls whether C# 11 "operator checked" is supported.
+		/// </summary>
+		public bool SupportOperatorChecked { get; set; }
+
 		/// <summary>
 		/// Controls whether all fully qualified type names should be prefixed with "global::".
 		/// </summary>
@@ -2224,6 +2229,8 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 				return ConvertMethod(op);
 			if (opType == OperatorType.UnsignedRightShift && !SupportUnsignedRightShift)
 				return ConvertMethod(op);
+			if (!SupportOperatorChecked && OperatorDeclaration.IsChecked(opType.Value))
+				return ConvertMethod(op);
 
 			OperatorDeclaration decl = new OperatorDeclaration();
 			decl.Modifiers = GetMemberModifiers(op);

ICSharpCode.Decompiler/CSharp/Transforms/ReplaceMethodCallsWithOperators.cs

@@ -16,6 +16,7 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 // DEALINGS IN THE SOFTWARE.
 
+using System;
 using System.Linq;
 using System.Reflection;
 
@@ -142,10 +143,19 @@ namespace ICSharpCode.Decompiler.CSharp.Transforms
 					break;
 			}
 
-			BinaryOperatorType? bop = GetBinaryOperatorTypeFromMetadataName(method.Name, context.Settings);
+			bool isChecked;
+			BinaryOperatorType? bop = GetBinaryOperatorTypeFromMetadataName(method.Name, out isChecked, context.Settings);
 			if (bop != null && arguments.Length == 2)
 			{
 				invocationExpression.Arguments.Clear(); // detach arguments from invocationExpression
+				if (isChecked)
+				{
+					invocationExpression.AddAnnotation(AddCheckedBlocks.CheckedAnnotation);
+				}
+				else if (HasCheckedEquivalent(method))
+				{
+					invocationExpression.AddAnnotation(AddCheckedBlocks.UncheckedAnnotation);
+				}
 				invocationExpression.ReplaceWith(
 					new BinaryOperatorExpression(
 						arguments[0].UnwrapInDirectionExpression(),
@@ -155,9 +165,17 @@ namespace ICSharpCode.Decompiler.CSharp.Transforms
 				);
 				return;
 			}
-			UnaryOperatorType? uop = GetUnaryOperatorTypeFromMetadataName(method.Name);
+			UnaryOperatorType? uop = GetUnaryOperatorTypeFromMetadataName(method.Name, out isChecked, context.Settings);
 			if (uop != null && arguments.Length == 1)
 			{
+				if (isChecked)
+				{
+					invocationExpression.AddAnnotation(AddCheckedBlocks.CheckedAnnotation);
+				}
+				else if (HasCheckedEquivalent(method))
+				{
+					invocationExpression.AddAnnotation(AddCheckedBlocks.UncheckedAnnotation);
+				}
 				if (uop == UnaryOperatorType.Increment || uop == UnaryOperatorType.Decrement)
 				{
 					// `op_Increment(a)` is not equivalent to `++a`,
@@ -174,17 +192,27 @@ namespace ICSharpCode.Decompiler.CSharp.Transforms
 							).CopyAnnotationsFrom(invocationExpression)
 						);
 					}
-					return;
 				}
-				arguments[0].Remove(); // detach argument
-				invocationExpression.ReplaceWith(
-					new UnaryOperatorExpression(uop.Value, arguments[0].UnwrapInDirectionExpression()).CopyAnnotationsFrom(invocationExpression)
-				);
+				else
+				{
+					arguments[0].Remove(); // detach argument
+					invocationExpression.ReplaceWith(
+						new UnaryOperatorExpression(uop.Value, arguments[0].UnwrapInDirectionExpression()).CopyAnnotationsFrom(invocationExpression)
+					);
+				}
 				return;
 			}
-			if (method.Name == "op_Explicit" && arguments.Length == 1)
+			if (method.Name is "op_Explicit" or "op_CheckedExplicit" && arguments.Length == 1)
 			{
 				arguments[0].Remove(); // detach argument
+				if (method.Name == "op_CheckedExplicit")
+				{
+					invocationExpression.AddAnnotation(AddCheckedBlocks.CheckedAnnotation);
+				}
+				else if (HasCheckedEquivalent(method))
+				{
+					invocationExpression.AddAnnotation(AddCheckedBlocks.UncheckedAnnotation);
+				}
 				invocationExpression.ReplaceWith(
 					new CastExpression(context.TypeSystemAstBuilder.ConvertType(method.ReturnType), arguments[0].UnwrapInDirectionExpression())
 						.CopyAnnotationsFrom(invocationExpression)
@@ -200,6 +228,14 @@ namespace ICSharpCode.Decompiler.CSharp.Transforms
 			return;
 		}
 
+		internal static bool HasCheckedEquivalent(IMethod method)
+		{
+			string name = method.Name;
+			if (name.StartsWith("op_", StringComparison.Ordinal))
+				name = "op_Checked" + name.Substring(3);
+			return method.DeclaringType.GetMethods(m => m.IsOperator && m.Name == name).Any();
+		}
+
 		bool IsInstantiableTypeParameter(IType type)
 		{
 			return type is ITypeParameter tp && tp.HasDefaultConstructorConstraint;
@@ -350,8 +386,9 @@ namespace ICSharpCode.Decompiler.CSharp.Transforms
 			}
 		}
 
-		static BinaryOperatorType? GetBinaryOperatorTypeFromMetadataName(string name, DecompilerSettings settings)
+		static BinaryOperatorType? GetBinaryOperatorTypeFromMetadataName(string name, out bool isChecked, DecompilerSettings settings)
 		{
+			isChecked = false;
 			switch (name)
 			{
 				case "op_Addition":
@@ -362,6 +399,18 @@ namespace ICSharpCode.Decompiler.CSharp.Transforms
 					return BinaryOperatorType.Multiply;
 				case "op_Division":
 					return BinaryOperatorType.Divide;
+				case "op_CheckedAddition" when settings.CheckedOperators:
+					isChecked = true;
+					return BinaryOperatorType.Add;
+				case "op_CheckedSubtraction" when settings.CheckedOperators:
+					isChecked = true;
+					return BinaryOperatorType.Subtract;
+				case "op_CheckedMultiply" when settings.CheckedOperators:
+					isChecked = true;
+					return BinaryOperatorType.Multiply;
+				case "op_CheckedDivision" when settings.CheckedOperators:
+					isChecked = true;
+					return BinaryOperatorType.Divide;
 				case "op_Modulus":
 					return BinaryOperatorType.Modulus;
 				case "op_BitwiseAnd":
@@ -393,8 +442,9 @@ namespace ICSharpCode.Decompiler.CSharp.Transforms
 			}
 		}
 
-		static UnaryOperatorType? GetUnaryOperatorTypeFromMetadataName(string name)
+		static UnaryOperatorType? GetUnaryOperatorTypeFromMetadataName(string name, out bool isChecked, DecompilerSettings settings)
 		{
+			isChecked = false;
 			switch (name)
 			{
 				case "op_LogicalNot":
@@ -403,12 +453,21 @@ namespace ICSharpCode.Decompiler.CSharp.Transforms
 					return UnaryOperatorType.BitNot;
 				case "op_UnaryNegation":
 					return UnaryOperatorType.Minus;
+				case "op_CheckedUnaryNegation" when settings.CheckedOperators:
+					isChecked = true;
+					return UnaryOperatorType.Minus;
 				case "op_UnaryPlus":
 					return UnaryOperatorType.Plus;
 				case "op_Increment":
 					return UnaryOperatorType.Increment;
 				case "op_Decrement":
 					return UnaryOperatorType.Decrement;
+				case "op_CheckedIncrement" when settings.CheckedOperators:
+					isChecked = true;
+					return UnaryOperatorType.Increment;
+				case "op_CheckedDecrement" when settings.CheckedOperators:
+					isChecked = true;
+					return UnaryOperatorType.Decrement;
 				default:
 					return null;
 			}

ICSharpCode.Decompiler/DecompilerSettings.cs

@@ -155,12 +155,13 @@ namespace ICSharpCode.Decompiler
 				numericIntPtr = false;
 				utf8StringLiterals = false;
 				unsignedRightShift = false;
+				checkedOperators = false;
 			}
 		}
 
 		public CSharp.LanguageVersion GetMinimumRequiredVersion()
 		{
-			if (parameterNullCheck || scopedRef || requiredMembers || numericIntPtr || utf8StringLiterals || unsignedRightShift)
+			if (parameterNullCheck || scopedRef || requiredMembers || numericIntPtr || utf8StringLiterals || unsignedRightShift || checkedOperators)
 				return CSharp.LanguageVersion.CSharp11_0;
 			if (fileScopedNamespaces || recordStructs)
 				return CSharp.LanguageVersion.CSharp10_0;
@@ -1218,6 +1219,24 @@ namespace ICSharpCode.Decompiler
 			}
 		}
 
+		bool checkedOperators = true;
+
+		/// <summary>
+		/// Gets/Sets whether to use C# 11.0 user-defined checked operators.
+		/// </summary>
+		[Category("C# 11.0 / VS 2022.4")]
+		[Description("DecompilerSettings.CheckedOperators")]
+		public bool CheckedOperators {
+			get { return checkedOperators; }
+			set {
+				if (checkedOperators != value)
+				{
+					checkedOperators = value;
+					OnPropertyChanged();
+				}
+			}
+		}
+
 		bool showXmlDocumentation = true;
 
 		/// <summary>

ICSharpCode.Decompiler/IL/Instructions/CompoundAssignmentInstruction.cs

@@ -315,7 +315,18 @@ namespace ICSharpCode.Decompiler.IL
 		{
 			this.Method = method;
 			Debug.Assert(Method.IsOperator || IsStringConcat(method));
-			Debug.Assert(evalMode == CompoundEvalMode.EvaluatesToNewValue || (Method.Name == "op_Increment" || Method.Name == "op_Decrement"));
+			Debug.Assert(evalMode == CompoundEvalMode.EvaluatesToNewValue || IsIncrementOrDecrement(method));
+		}
+
+		public static bool IsIncrementOrDecrement(IMethod method, DecompilerSettings? settings = null)
+		{
+			if (!(method.IsOperator && method.IsStatic))
+				return false;
+			if (method.Name is "op_Increment" or "op_Decrement")
+				return true;
+			if (method.Name is "op_CheckedIncrement" or "op_CheckedDecrement")
+				return settings?.CheckedOperators ?? true;
+			return false;
 		}
 
 		public static bool IsStringConcat(IMethod method)

ICSharpCode.Decompiler/IL/Transforms/FixRemainingIncrements.cs

@@ -31,7 +31,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 			var callsToFix = new List<Call>();
 			foreach (var call in function.Descendants.OfType<Call>())
 			{
-				if (!(call.Method.IsOperator && (call.Method.Name == "op_Increment" || call.Method.Name == "op_Decrement")))
+				if (!UserDefinedCompoundAssign.IsIncrementOrDecrement(call.Method, context.Settings))
 					continue;
 				if (call.Arguments.Count != 1)
 					continue;

ICSharpCode.Decompiler/IL/Transforms/TransformAssignment.cs

@@ -392,7 +392,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 				}
 				else if (operatorCall.Arguments.Count == 1)
 				{
-					if (!(operatorCall.Method.Name == "op_Increment" || operatorCall.Method.Name == "op_Decrement"))
+					if (!UserDefinedCompoundAssign.IsIncrementOrDecrement(operatorCall.Method, context.Settings))
 						return false;
 					// use a dummy node so that we don't need a dedicated instruction for user-defined unary operator calls
 					rhs = new LdcI4(1);
@@ -988,7 +988,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 			{
 				if (!operatorCall.Arguments[0].MatchLdLoc(tmpVar))
 					return false;
-				if (!(operatorCall.Method.Name == "op_Increment" || operatorCall.Method.Name == "op_Decrement"))
+				if (!UserDefinedCompoundAssign.IsIncrementOrDecrement(operatorCall.Method, context.Settings))
 					return false;
 				if (operatorCall.IsLifted)
 					return false; // TODO: add tests and think about whether nullables need special considerations

ICSharpCode.Decompiler/Output/IAmbience.cs

@@ -113,6 +113,10 @@ namespace ICSharpCode.Decompiler.Output
 		/// Support <c>&gt;&gt;&gt;</c> as unsigned right shift operator.
 		/// </summary>
 		SupportUnsignedRightShift = 0x80000,
+		/// <summary>
+		/// Support C# 11 <c>operator checked</c>.
+		/// </summary>
+		SupportOperatorChecked = 0x100000,
 
 		StandardConversionFlags = ShowParameterNames |
 			ShowAccessibility |
@@ -127,7 +131,7 @@ namespace ICSharpCode.Decompiler.Output
 			ShowDefinitionKeyword |
 			ShowBody,
 
-		All = 0x7ffff,
+		All = 0x1fffff,
 	}
 
 	/// <summary>

ILSpy/Languages/CSharpLanguage.cs

@@ -753,6 +753,10 @@ namespace ICSharpCode.ILSpy
 			{
 				flags |= ConversionFlags.SupportUnsignedRightShift;
 			}
+			if (settings.CheckedOperators)
+			{
+				flags |= ConversionFlags.SupportOperatorChecked;
+			}
 			if (settings.InitAccessors)
 			{
 				flags |= ConversionFlags.SupportInitAccessors;

ILSpy/Properties/Resources.Designer.cs

@@ -765,6 +765,15 @@ namespace ICSharpCode.ILSpy.Properties {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to User-defined checked operators.
+        /// </summary>
+        public static string DecompilerSettings_CheckedOperators {
+            get {
+                return ResourceManager.GetString("DecompilerSettings.CheckedOperators", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to Decompile anonymous methods/lambdas.
         /// </summary>

ILSpy/Properties/Resources.resx

@@ -279,6 +279,9 @@ Are you sure you want to continue?</value>
   <data name="DecompilerSettings.AsyncEnumerator" xml:space="preserve">
     <value>Decompile async IAsyncEnumerator methods</value>
   </data>
+  <data name="DecompilerSettings.CheckedOperators" xml:space="preserve">
+    <value>User-defined checked operators</value>
+  </data>
   <data name="DecompilerSettings.DecompileAnonymousMethodsLambdas" xml:space="preserve">
     <value>Decompile anonymous methods/lambdas</value>
   </data>