TCMK.c

#include <stdio.h>

void add(unsigned long long *dst, unsigned long long *src){

asm ("movq %0, %%rbx\n"
     /*"addq $8, %%rbx\n"*/
     "movq (%%rbx), %%rax\n"
     "addq (%1), %%rax\n"
     "mov %%rax, (%%rbx)\n"
     /*"adcq $0, %%rax\n"*/
     /*"addq $8, %%rbx\n"*/
     /*"mov %%rax, (%%rbx)\n"*/
     : /* No outputs. */
     : "r" (dst), "r" (src)
     : "rax", "rbx");

}


int main(){
   unsigned long long a[3], b[3];
   a[0]=1;
   a[1]=-1;
   a[2]=0;

   b[0]=1;
   b[1]=1;
   b[2]=0;

   add(a,b);

   printf("%x %x %x\n",a[0],a[1],a[2]);
   printf("%x %x %x\n",b[0],b[1],b[2]);
}