Remove hack that prevented inlining of the first instruction in each block.

Now that ILReader already creates the basic blocks and BlockBuilder only arranges them in containers, this code is no longer necessary.

ICSharpCode.Decompiler/IL/ControlFlow/ControlFlowSimplification.cs

@@ -258,7 +258,7 @@ namespace ICSharpCode.Decompiler.IL.ControlFlow
 			if (targetBlock.StartILOffset < block.StartILOffset && IsDeadTrueStore(block))
 			{
 				// The C# compiler generates a dead store for the condition of while (true) loops.
-				block.Instructions.RemoveRange(block.Instructions.Count - 3, 2);
+				block.Instructions.RemoveAt(block.Instructions.Count - 2);
 			}
 
 			if (block.ILRangeIsEmpty)
@@ -275,15 +275,13 @@ namespace ICSharpCode.Decompiler.IL.ControlFlow
 		/// </summary>
 		private static bool IsDeadTrueStore(Block block)
 		{
-			if (block.Instructions.Count < 3)
+			if (block.Instructions.Count < 2)
 				return false;
-			if (!(block.Instructions.SecondToLastOrDefault() is StLoc deadStore && block.Instructions[block.Instructions.Count - 3] is StLoc tempStore))
+			if (!(block.Instructions.SecondToLastOrDefault() is StLoc deadStore))
 				return false;
 			if (!(deadStore.Variable.LoadCount == 0 && deadStore.Variable.AddressCount == 0))
 				return false;
-			if (!(deadStore.Value.MatchLdLoc(tempStore.Variable) && tempStore.Variable.IsSingleDefinition && tempStore.Variable.LoadCount == 1))
-				return false;
-			return tempStore.Value.MatchLdcI4(1) && deadStore.Variable.Type.IsKnownType(KnownTypeCode.Boolean);
+			return deadStore.Value.MatchLdcI4(1) && deadStore.Variable.Type.IsKnownType(KnownTypeCode.Boolean);
 		}
 	}
 }

ICSharpCode.Decompiler/IL/ILReader.cs

@@ -514,14 +514,6 @@ namespace ICSharpCode.Decompiler.IL
 					FlushExpressionStack();
 					block.Block.Instructions.Add(inst);
 				}
-				else if (start == block.StartILOffset)
-				{
-					// If this instruction is the first in a new block, avoid it being inlined
-					// into the next instruction.
-					// This is necessary because the BlockBuilder uses inst.StartILOffset to
-					// detect block starts, and doesn't search nested instructions.
-					FlushExpressionStack();
-				}
 
 				if ((!decodedInstruction.PushedOnExpressionStack && IsSequencePointInstruction(inst)) || startedWithEmptyStack)
 				{