@swift-5.1.5 -Xfrontend -emit-sil -Xfrontend -parse-as-library -O

func main() -> Int { let hoge: Int? = 1 let fuga = hoge .map { $0 * 2 } .map { $0 + 3 } .map { $0 * 4 } return fuga ?? 99 }

(edited)