idk

test/tail.ssa

@@ -4,5 +4,7 @@ function w $factorial (w %n, w %acc) {
 @z
 	ret %acc
 @nz
-	tail
+	%n_next =w sub %n, 1
+	%acc_next =w mul %n, %acc
+	tail $factorial (w %n_next, w %acc)
 }