The IR is pretty messy but if you can see through the clutter the IR is much easier to read the flow of. There's a reason why we use SSA (although prior to mem2reg running you don't quite have it, but still)
Yes, exactly. Clang emitted IR especially has a lot of (C/C++)-specific junk. If you look past that clutter, it's not too bad.
I think the best way to learn to read IR is to look at super-minimal examples, and then you'll be able to tell which parts of larger IR files are relevant.
