Add TODO about using `switch` instruction
diff --git a/wasm/proposals/suspend_fun_with_stack_switching.md b/wasm/proposals/suspend_fun_with_stack_switching.md
index e77b7a4..2136c29 100644
--- a/wasm/proposals/suspend_fun_with_stack_switching.md
+++ b/wasm/proposals/suspend_fun_with_stack_switching.md
@@ -156,6 +156,10 @@
* could be fully managed on call site???
* for multithreading, it should be thread local
+### Using `switch` instruction
+TODO
+* Can we implement same things with switch instruction?
+* May a such implementation be more performant?
## Useful links
* https://kotlinlang.org/docs/coroutines-overview.html
