# counting_bits.asm
	
.data
.text
.global main
main:
    mov $0xA3, %ebx # value to count bits in
    mov $0, %ecx    # bit counter
check_zero:
    cmp $0, %ebx    # done? (that is, no more bits)
    jz done
    mov %ecx, %edx  # lsb of %ecx set?
    and $0x01, %edx
    jz lsb_is_zero
    add %1, %ecx    # if so, count it
lsb_is_zero:
    shr %ebx, $0x01 # shift off the bit just counted
    jmp check_zero  # try next bit
done:
    mov %ecx, %eax
    ret