So I just noticed that since r15 doesn't alias the programme counter, the arm mechanism of implementing pc-relative addressing wont work.
After a bit of searching it seems movfs can be used to access the PC, and I presume from that one could emulate a "load effective address" opcode. Although without assembler + linker support, the offset would need to be manually calculated and only work within single compilation units.
An 11-bit signed lea psuedo-op could be implemented using 2 instructions without requiring additional registers, movfs and add immediate. Is this, or some alternative mechanism planned/in the works for e-gas?
I also noticed that for all the language forums there isn't one for assembly language, although I wouldn't be fussed if it stayed that way.