[llvm] [llvm][dwarfdump] Add --child-tags option to filter by DWARF tags (PR #165720)

[Michael Buch via llvm-commits]

Michael137 wrote:

> Seems OK to me as a feature - though I wonder if we're getting to the point of "should have an arbitrary query language" for querying DWARF at this point? (did we ever end up with the json output for dwarfdump? perhaps that's the way to do it - dump to json and use jquery?)

i had the exact same line of thought when i initially started implementing this. What nudged me over the edge was that i prefer looking at dwarfdump output over json, though that’s admittedly a selfish reason. Ultimately i thought, if it’s not too much of a maintenance burden, might as well. Of course there’s always complexity of how various options interact, which in this case **seemed** ok. A more involved querying feature (like filtering by attribute value/existence), which I’d love to have, is probably not worth adding to the current infrastructure because of how complex it would be to implement (afaict).

But yea, happy to hear others chime in on usefulness/if it’s acceptable maintenance-wise, and whether there is appetite for something more complete.

https://github.com/llvm/llvm-project/pull/165720