Scan for first zero bit (Assembly)?
- by cthulhu
I have some numbers in AH, AL, BL, BH registers.
I need to check whether there is 0 bit in each of the registers in left half of the number.
If yes, then put into check variable value 10 else -10.
How can I do this?
I tried something like that:
org 100h
check dw 0
mov ah, 11111111b
mov al, 11111111b
mov bl, 11111111b
mov bh, 11111111b
mov check, -10
shr ah, 4
shr al, 4
shr bl, 4
shr bh, 4
cmp ah, 0Fh
jz first
first:
cmp al, 0Fh
jz second
second:
cmp bl, 0Fh
jz third
third:
cmp bh, 0Fh
jz final
final:
mov check, 10
ret
