Function AtomicAdd

library/cpp/lfalloc/lf_allocX64.h:36–38

using TAtomic = volatile long;

static inline long AtomicAdd(TAtomic& a, long b) {
    return _InterlockedExchangeAdd(&a, b) + b;
}

static inline long AtomicSub(TAtomic& a, long b) {
    return AtomicAdd(a, -b);