Fix #1075: NullReferenceException in StatementBuilder.TranslateSwitch

ICSharpCode.Decompiler/CSharp/StatementBuilder.cs

@@ -112,7 +112,6 @@ namespace ICSharpCode.Decompiler.CSharp
 
 		SwitchStatement TranslateSwitch(BlockContainer switchContainer, SwitchInstruction inst)
 		{
-			Debug.Assert(switchContainer.EntryPoint.IncomingEdgeCount == 1);
 			var oldBreakTarget = breakTarget;
 			breakTarget = switchContainer; // 'break' within a switch would only leave the switch
 			var oldCaseLabelMapping = caseLabelMapping;
@@ -159,7 +158,7 @@ namespace ICSharpCode.Decompiler.CSharp
 				switch (section.Body) {
 					case Branch br:
 						// we can only inline the block, if all branches are in the switchContainer.
-						if (br.TargetBlock.Parent == switchContainer && switchContainer.Descendants.OfType<Branch>().Where(b => b.TargetBlock == br.TargetBlock).All(b => BlockContainer.FindClosestSwitchContainer(b) == switchContainer))
+						if (br.TargetContainer == switchContainer && switchContainer.Descendants.OfType<Branch>().Where(b => b.TargetBlock == br.TargetBlock).All(b => BlockContainer.FindClosestSwitchContainer(b) == switchContainer))
 							caseLabelMapping.Add(br.TargetBlock, firstValueResolveResult);
 						break;
 					default:
@@ -173,7 +172,7 @@ namespace ICSharpCode.Decompiler.CSharp
 				switch (section.Body) {
 					case Branch br:
 						// we can only inline the block, if all branches are in the switchContainer.
-						if (br.TargetBlock.Parent == switchContainer && switchContainer.Descendants.OfType<Branch>().Where(b => b.TargetBlock == br.TargetBlock).All(b => BlockContainer.FindClosestSwitchContainer(b) == switchContainer))
+						if (br.TargetContainer == switchContainer && switchContainer.Descendants.OfType<Branch>().Where(b => b.TargetBlock == br.TargetBlock).All(b => BlockContainer.FindClosestSwitchContainer(b) == switchContainer))
 							ConvertSwitchSectionBody(astSection, br.TargetBlock);
 						else
 							ConvertSwitchSectionBody(astSection, section.Body);

ICSharpCode.Decompiler/IL/Instructions/BlockContainer.cs

@@ -193,6 +193,7 @@ namespace ICSharpCode.Decompiler.IL
 				case ContainerKind.Switch:
 					Debug.Assert(EntryPoint.Instructions.Count == 1);
 					Debug.Assert(EntryPoint.Instructions[0] is SwitchInstruction);
+					Debug.Assert(EntryPoint.IncomingEdgeCount == 1);
 					break;
 				case ContainerKind.While:
 					Debug.Assert(EntryPoint.IncomingEdgeCount > 1);