[llvm] [DWARFLinker][DWARFLinkerParallel][NFC] Refactor DWARFLinker&DWARFLinkerParallel to have a common library. Part 1. (PR #75925)

[via llvm-commits]

avl-llvm wrote:

> The base class looks good but I would prefer a slight change to the directory layout and namespaces. Particularly the distinction between "Apple" and "LLVM" bothers me. I understand how you ended up there, but I think it unnecessary associates the algorithm with particular vendors. How about "Parallel" and "Classic"?

That is perfectly fine for me. Would you like to change command line option also? 

dsymutil --linker=[classic,parallel] 

Or it would be only directories/namespaces change only?

> 
> With that naming scheme, what I'd like this to look like would be:
> 
>     * The `DWARFLinker/` root directory contains shared classes and lives in the `dwarflinker` namespace. I think it should probably be `dwarf_linker` but I'm fine with `dwarflinker` if that's too much churn.
> 
>     * The `DWARFLinker/Classic` directory containing classes needed for the dsymutil lockstep algorithm. Everything here should live under the `dwarf(_)linker::classic` namespace.
> 
>     * The `DWARFLinker/Parallel` directory containing classes needed for the parallel algorithm. Everything here should live under the `dwarf(_)linker::parallel` namespace.



https://github.com/llvm/llvm-project/pull/75925