"1:\t" "lwarx %0,0,%1\n" /* load and reserve */
"add %0,%2,%0\n" /* add val to value loaded */
"stwcx. %0,0,%1\n" /* store conditional */
"1:\t" "lwarx %0,0,%1\n" /* load and reserve */
"add %0,%2,%0\n" /* add val to value loaded */
"stwcx. %0,0,%1\n" /* store conditional */