[llvm] [LLVM][DWARF] Add compilation directory and dwo name to TU in dwo section (PR #74909)

[David Blaikie via llvm-commits]

dwblaikie wrote:

> > Looks OK.
> > We could potentially do this in all DWARF versions, not just >= 5. (seems relatively harmless to do it in the v4 extension version of Split DWARF?)
> > & could you get some measurements, especially .o file size (or more specifically, .o .debug_info size) for a clang build with this patch/without this patch? Just so we know what sort of growth to expect.
> 
> We can, but then it just increases complexity, slightly, + more tests modified, probably, since then there will be else statement for GNU_dwo_name.

Ah, fair enough - yeah, if it wouldn't simplify the code, I wouldn't bother with it.

> OK, will see what increase in clang is.

Thanks!

https://github.com/llvm/llvm-project/pull/74909