collapseos/blk/446

( TODO: move these words with other native words. )
H@ 4 + XCURRENT ! ( make next CODE have 0 prev field )
CODE (br) L1 BSET ( used in ?br )
    DI DX MOVxx, AL [DI] MOVr[], AH AH XORrr, CBW,
    DX AX ADDxx,
;CODE
CODE (?br)
    AX POPx, AX AX ORxx, JZ, L1 @ RPCs, ( False, branch )
    ( True, skip next byte and don't branch )
    DX INCx,
;CODE