'unknown instruction' on macOS

[Sijmen J. Mulder]

Hi,

On master at 79cd05ad, I get this when building on macOS (on ARM, if
that matters):

  pkl-gen.pks:27: unknown instruction
          unmap
  pkl-asm.pks:27: unknown instruction
          ogetm                   ; OFF OGETM
  pkl-asm.pks:28: unknown instruction
          swap                    ; OGETM OFF
  pkl-asm.pks:29: unknown instruction
          ogetu                   ; OGETM OFF OGETU
  pkl-asm.pks:30: unknown instruction
          rot                     ; OFF OGETU OGETM
  pkl-asm.pks:31: unknown instruction
          mullu
  pkl-asm.pks:32: unknown instruction
          nip2                    ; OFF (OGETU*OGETM

Full build log here, against a slightly earlier commit:
https://sjmulder.nl/tmp/poke-full.log

jemarch and I have been trying some things and applied some fixes, but
for now the problem remains. Perhaps this weekend I can learn some more
about how this is supposed to work and find out the root cause of the
issue.

Sijmen