-inline uint32_t Atomic::compare_and_swap(volatile uint32_t *p, uint32_t oldval, uint32_t newval)
-{
- uint32_t result;
- uint32_t temp;
-
- /* TODO: improve this one! */
- __asm__ __volatile__ (
- "1:\t"
- "ldr %0,[%2]\n\t"
- "cmp %0,%4\n\t"
- "bne 2f\n\t"
- "swp %1,%3,[%2]\n\t"
- "cmp %1,%0\n\t"
- "swpne %0,%1,[%2]\n\t"
- "bne 1b\n\t"
- "2:"
- : "=&r" (result), "=&r" (temp)
- : "r" (p), "r" (newval), "r" (oldval)
- : "cc", "memory"
- );
-
- return result;
-}