[lld] r308544 - Speed up gdb index creation.

[George Rimar via llvm-commits]

>Speed up gdb index creation.
>
>With that in place we can use lld's own infrastructure for the low
>level detail of dwarf parsing.
>
>With this we don't decompress sections twice, we don't scan all
>realocations and even with this simplistic implementation linking
>clang with gdb index goes from 34.09 seconds to 20.80 seconds.
>

Great, thanks for working on that !

Do you think we can try parallelizing building index now or we still
need to do something else for single-threaded case ?

George.