Loacation Counters and Code Segment

How these location counters have been calculate for code segment :

 0000               codesg Segment
                Assume cs:codesg,ds:datasg
 0000               Main proc Far
 0000  B8 ---- R            mov ax,seg datasg
 0003  8B D0                mov dx,ax
 0005  A1 000A R            mov ax,b2+2
 0008  50               push ax
 0009  A1 000A R        l1: mov ax,x
 000C  40               inc ax
 000D开发者_如何学Python  3C 05                cmp al,5
 000F  75 09                jne l2
 0011  8B 0E 0008 R         mov cx,a2+2
 0015  E2 F2                loop l1
 0017  B8 0000              mov ax,0
 001A  CB           l2: ret
 001B               main endp
 001B               codesg ends

You just add the number of bytes in the current instruction to the current location counter and that becomes the new location counter. So if you start at location 0 and you have a 3 byte instruction then the location counter for the next instruction will be 3.