aa.c

   1 /* filename :aa.c */
   2 #include <stdio.h>
   3
   4 int main(void)
   5 {
   6         unsigned long long tmp = 2;
   7
   8         /* 下面这样改成asm volatile("addq $0x7fffffff, %0" 就可以 */
   9         //asm volatile("movq $0x1122334455667788, %0"
  10         asm volatile("addq $0x1122334455667788, %0"
  11                      : "=a" (tmp)
  12                      : "0" (tmp)
  13                     );
  14
  15         printf("tmp is %p\n", tmp);
  16
  17         return 0;
  18 }
  19