assert rc_mode==False, "ffirst RC1 only possible when Rc=0"
else:
assert src_zero == 0, "src-zero not allowed in ffirst BO"
assert rc_mode==False, "ffirst RC1 only possible when Rc=0"
else:
assert src_zero == 0, "src-zero not allowed in ffirst BO"
# sanity-check that 2Pred mask is same mode
if has_pmask and has_smask:
assert smmode == pmmode, \
# sanity-check that 2Pred mask is same mode
if has_pmask and has_smask:
assert smmode == pmmode, \