[llvm] [SelectionDAG] Add a flag to sort DAGs before showing them in debug prints (PR #149732)

[Min-Yih Hsu via llvm-commits]

mshockwave wrote:

> Or we could focus efforts on finally ensuring the DAG is topologically sorted to begin with: #83422

True, aside from the problems raised in the said issue, I remember compilation time is/was also a concern?

But in any case, I feel like this patch can provide a quick and easy solution for improving developers' life, at least in a short term.

https://github.com/llvm/llvm-project/pull/149732