Reduce LINQ calls on `CellList`

src/BizHawk.Client.EmuHawk/CustomControls/InputRoll/Cell.cs

@@ -2,6 +2,7 @@
 using System.Diagnostics;
 
 using BizHawk.Common;
+using BizHawk.Common.CollectionExtensions;
 
 namespace BizHawk.Client.EmuHawk
 {
@@ -105,6 +106,21 @@ namespace BizHawk.Client.EmuHawk
 			}
 			_list.Insert(~i, item);
 		}
+
+		public bool IncludesRow(int rowIndex)
+#if false
+			=> _list.Exists(cell => cell.RowIndex == rowIndex);
+#elif false
+		{
+			var i = _list.BinarySearch(new() { RowIndex = rowIndex, Column = null });
+			return i >= 0 || (~i < _list.Count && _list[~i].RowIndex == rowIndex);
+		}
+#else
+		{
+			var i = _list.LowerBoundBinarySearch(static c => c.RowIndex ?? -1, rowIndex);
+			return i >= 0 && _list[i].RowIndex == rowIndex;
+		}
+#endif
 	}
 
 	public static class CellExtensions

src/BizHawk.Client.EmuHawk/CustomControls/InputRoll/InputRoll.cs

@@ -969,7 +969,7 @@ namespace BizHawk.Client.EmuHawk
 			=> SelectedRowsWithDuplicates.First();
 
 		public bool IsRowSelected(int rowIndex)
-			=> _selectedItems.Any(cell => cell.RowIndex == rowIndex);
+			=> _selectedItems.IncludesRow(rowIndex);
 
 		public IEnumerable<ToolStripItem> GenerateContextMenuItems()
 		{
@@ -1159,12 +1159,12 @@ namespace BizHawk.Client.EmuHawk
 					}
 					else if (ModifierKeys == Keys.Shift && CurrentCell.Column.Type == ColumnType.Text)
 					{
-						if (_selectedItems.Any())
+						if (_selectedItems.Count is not 0)
 						{
 							if (FullRowSelect)
 							{
 								var targetRow = CurrentCell.RowIndex.Value;
-								if (!_selectedItems.Any(c => c.RowIndex == targetRow))
+								if (!_selectedItems.IncludesRow(targetRow))
 								{
 									int additionStart, additionEndExcl;
 									SortedList<int> rowIndices = new(SelectedRows);
@@ -1465,8 +1465,8 @@ namespace BizHawk.Client.EmuHawk
 				{
 					if (MultiSelect && _lastSelectedRow > 0)
 					{
-						if (_selectedItems.Any(i => i.RowIndex == _lastSelectedRow.Value)
+						if (_selectedItems.IncludesRow(_lastSelectedRow.Value)
-							&& _selectedItems.Any(i => i.RowIndex == _lastSelectedRow - 1)) // Unhighlight if already highlighted
+							&& _selectedItems.IncludesRow(_lastSelectedRow.Value - 1)) // Unhighlight if already highlighted
 						{
 							SelectRow(_lastSelectedRow.Value, false);
 						}
@@ -1482,8 +1482,8 @@ namespace BizHawk.Client.EmuHawk
 				{
 					if (MultiSelect && _lastSelectedRow < RowCount - 1)
 					{
-						if (_selectedItems.Any(i => i.RowIndex == _lastSelectedRow.Value)
+						if (_selectedItems.IncludesRow(_lastSelectedRow.Value)
-							&& _selectedItems.Any(i => i.RowIndex == _lastSelectedRow + 1)) // Unhighlight if already highlighted
+							&& _selectedItems.IncludesRow(_lastSelectedRow.Value + 1)) // Unhighlight if already highlighted
 						{
 							var origIndex = _lastSelectedRow.Value;
 							SelectRow(origIndex, false);
@@ -1787,8 +1787,9 @@ namespace BizHawk.Client.EmuHawk
 
 				if (FullRowSelect)
 				{
-					if (toggle && (_selectedItems.RemoveAll(x => x.RowIndex == row) is not 0))
+					if (toggle && _selectedItems.IncludesRow(row))
 					{
+						_selectedItems.RemoveAll(x => x.RowIndex == row);
 						_lastSelectedRow = _selectedItems.LastOrDefault()?.RowIndex;
 					}
 					else
@@ -1803,7 +1804,7 @@ namespace BizHawk.Client.EmuHawk
 				else
 				{
 					_lastSelectedRow = null; // TODO: tracking this by cell is a lot more work
-					if (toggle && _selectedItems.Any(x => x.RowIndex == row))
+					if (toggle && _selectedItems.IncludesRow(row))
 					{
 						var item = _selectedItems
 							.FirstOrDefault(x => x.Equals(cell));

src/BizHawk.Common/CustomCollections.cs

@@ -71,6 +71,9 @@ namespace BizHawk.Common
 
 		public virtual void CopyTo(T[] array, int arrayIndex) => _list.CopyTo(array, arrayIndex);
 
+		public T FirstOrDefault()
+			=> _list.Count is 0 ? default! : _list[0];
+
 		public virtual IEnumerator<T> GetEnumerator() => _list.GetEnumerator();
 
 		/// <remarks>throws if list is empty</remarks>
@@ -87,6 +90,9 @@ namespace BizHawk.Common
 			return i < 0 ? -1 : i;
 		}
 
+		public T LastOrDefault()
+			=> _list.Count is 0 ? default! : _list[_list.Count - 1];
+
 		public virtual bool Remove(T item)
 		{
 #if true