求教解决方案

求教
没了inc si，那么这个程序就不能过滤了么?

Assembly code

assume cs:code,ds:datadata segment    db 'dfadfasfd',0data endscode segmentstart:    mov ax,data        mov ds,ax        mov si,0        call capital        inc sicapital:mov cl,[si]        mov ch,0        jcxz ok        and byte ptr [si],11011111b        inc si        jmp short capitalok:        retcode endsend start

Assembly code

assume  cs:code,ds:datadata    segment        db      'sdfwersdddd'data    endscode    segmentstart:        mov ax,data        mov ds,ax        mov si,0        call cap        mov ah,4ch        int 21h;cap     procs:        cmp byte ptr [si],0        jz ok        and byte ptr [si],11011111b        inc si        jmp sok:        retcap     endp;code    endsend     start