{
	// This is not joined because a is referenced multiple times
	let a := mload(2)
	let b := mload(a)
	a := 4
}
// ----
// step: expressionJoiner
//
// {
//     {
//         let a := mload(2)
//         let b := mload(a)
//         a := 4
//     }
// }