[llvm] [llvm-dwp] Adds --prioritize-discard-path to explicitly control dwp overflow order. (PR #180909)

[David Blaikie via llvm-commits]

dwblaikie wrote:

> > For the record - I don't feel great about this direction of soft stop, and continuing to produce "best effort" DWPs for continuingly changing definitions of "best".
> > Please do investigate reducing your binary size, or reducing debug info contents itself (better homing strategies, more compact encodings, etc) and implementing DWARF64 .debug_cu_index to scale better.
> 
> Although we currently make extensive use of soft stop, I agree with your point and we are moving in that direction. Next, I will promote the adoption of DWARF64 in some internal projects.

To clarify - DWARF64 in general probably has some large debug info size costs, but DWARF64 /just/ for the debug_str_offsets.dwo and debug_cu_index.dwo sections in dwp files when needed (the dwp tool would dynamically decide whether to use DWARF64 encoding if the contribution to the section needed to encode values larger than DWARF32 supports) would be the idea - minimizing the cost/paying the price only where needed.

https://github.com/llvm/llvm-project/pull/180909