offset() and val_offset()

[markus-metzger]

We use that same phrase as in

dwarf-locations/010-generalize-offsetting.txt

Line 300 in 00e62e0

context, except the result kind is a location description, the

to describe offset() and val_offset(). The former actually is a location description, whereas the latter isn't, using the DWARF-5 definitions.

[t-tye]

In the proposal the CFA is generalized to be a location description rather than a default address space memory address value as in DWARF 5. This allows it to encode location storage other than the default address space memory. For AMD GPU the CFA is in a different address space. So in both offset(N) and val_offset(N) the CFA location description is offset by N. The difference is that offset(N) is that resulting location description (which can still record the address space of the CFA, which was not possible with DWARF 5). And val_offset(N) is the memory address of the resulting memory location description (which looses the address space information so cannot be used for AMD GPU).