The way I’ve always read this is that the lines with ch needs their ordering preserved at each level.
BTW, Its normally a lot easier to understand if you view the DAG in graphviz format using the -view-* options for dags here. Again as mentioned there, for large graphs, using the filter-view-dags allows with visualizing just the basic blocks of interest.
Sidenote: I can’t be the only one who finds it quite annoying to see you post this same image in all of your questions from the past week. It takes up a lot of screen space and clutters your question unnecessarily; please don’t.