T2
Click on the red underlined text to get to the source
... T1,^D8 ; shift UCS-4 value
ILDB T2,P1 ; get next nonet
TRZE T2,400 ; extract octet, any continuation?
...
... ILDB T2,P1 ; get next nonet
TRZE T2,400 ; extract octet, any continuation?
JRST U92U41 ; yes, continue
XOR ...
... ; Returns +1: Always, P1/ updated byte pointer
; Clobbers T1, T2; (T1, T2) must be an accumulator pair
...
... T2) must be an accumulator pair
U42UT9: SETO T2, ; we'll need some of these 1-bits later
ASHC T1 ...
... T1,U42U9X ; done if no more octets
LSHC T1,-^D8 ; shift next octet into T2
ROT T2,-1 ; turn it into nonet with high 1 bit ...
... T1,-^D8 ; shift next octet into T2
ROT T2,-1 ; turn it into nonet with high 1 bit
PUSHJ P,U42U91 ; recurse for remainder
...
... PUSHJ P,U42U91 ; recurse for remainder
U42U9X: LSHC T1,^D9 ; get next nonet back from T2
IDPB T1,P1 ; write nonet
...