text: static inline int8_t cmpxchg8(int8_t* ptr, int8_t oldval, int8_t newval);
  static inline int16_t cmpxchg16(int16_t* ptr, int16_t oldval, int16_t newval);
  static inline int32_t cmpxchg32(int32_t* ptr, int32_t oldval, int32_t newval);
  