- * Collect firm nodes that will probably modify the stack.
- * Put them into an order that respects all their dependencies.
+ * In the normal firm representation some nodes like pure calls, builtins
+ * have no memory inputs+outputs. However in the backend these sometimes have to
+ * access the stack to work and therefore suddenly need to be enqueued into the
+ * memory edge again.
+ * This API creates a possible order to enqueue them so we can be sure to create
+ * a legal dependency graph when transforming them.