[PATCH] D23768: [ELF] Linkerscript: eliminate LayoutInputSection

[Rafael Espíndola via llvm-commits]

> I think the code can be simplified further (I am experimenting with it), but this is a step in the right direction.

Some things I tried:

* Assigning offsets as we assign sections to output sections. That is
too early as '.' needs the address, and for that we need the alignment
of the output section.

* Storing in InputSectionDescription which sections it found. With
this assignOffsets can be simpler as we visit the assignments and
sections in the right order. This is probably worth it, but handling
the orphan sections is still a bit annoying.

I will probably send the second patch for review once this one is in.

Cheers,
Rafael