+ // Allow use of this class as the value itself.
+ operator unsigned() const { return Value; }
+ const Statistic &operator=(unsigned Val) {
+ Value = Val;
+ return init();
+ }
+
+ const Statistic &operator++() {
+ // FIXME: This function and all those that follow carefully use an
+ // atomic operation to update the value safely in the presence of
+ // concurrent accesses, but not to read the return value, so the
+ // return value is not thread safe.
+ sys::AtomicIncrement(&Value);
+ return init();
+ }
+
+ unsigned operator++(int) {
+ init();
+ unsigned OldValue = Value;
+ sys::AtomicIncrement(&Value);
+ return OldValue;
+ }
+
+ const Statistic &operator--() {
+ sys::AtomicDecrement(&Value);
+ return init();
+ }
+
+ unsigned operator--(int) {
+ init();
+ unsigned OldValue = Value;
+ sys::AtomicDecrement(&Value);
+ return OldValue;
+ }
+
+ const Statistic &operator+=(const unsigned &V) {
+ sys::AtomicAdd(&Value, V);
+ return init();
+ }
+
+ const Statistic &operator-=(const unsigned &V) {
+ sys::AtomicAdd(&Value, -V);
+ return init();
+ }
+
+ const Statistic &operator*=(const unsigned &V) {
+ sys::AtomicMul(&Value, V);
+ return init();
+ }
+
+ const Statistic &operator/=(const unsigned &V) {
+ sys::AtomicDiv(&Value, V);
+ return init();
+ }