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

[James Henderson via llvm-commits]

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@@ -0,0 +1,127 @@
+# Tests the --filter-child-tag (-t) option.
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jh7370 wrote:

Nit: I don't know if this has been adopted in llvm-dwarfdump tests at all yet, but in many other LLVM binary utils and related code, we've been adopting a policy of `##` for comment markers (or otherwise double-comment markers) to indicate true comments and to distinguish them from the lit/FileCheck commands. I find it really helps test readability. Example:

```
## Tests the --filter-child-tag (-t) option.
# RUN: ...
```

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