collapseos/blk/335

CODE LSHIFT ( n u -- n )
    DE POP, ( u )
    HL POP, ( n )
    chkPS,
    A E LDrr,
    A ORr, IFNZ,
        BEGIN,
            L SLA, H RL,
            A DECr,
        JRNZ, AGAIN,
    THEN,
    HL PUSH,
;CODE