#include <stdio.h>

int add(int a, int b)
{
    int result;
    asm volatile (
		"addl %2, %1;"      // Add b
        "movl %1, %0;"
        : "=r" (result)
        : "r" (a), "r" (b)
		: "cc"
	);
    return result;
}

int main(void)
{
	int x = 10, y = 20;
	printf("%d + %d = %d\n", x, y, add(x, y));
	return 0;
}