Function doNotOptimizeAway

src/bench/nanobench.h:999–1002

// see https://github.com/google/benchmark/blob/master/include/benchmark/benchmark.h#L307
template <typename T>
void doNotOptimizeAway(T const& val) {
    // NOLINTNEXTLINE(hicpp-no-assembler)
    asm volatile("" : : "r,m"(val) : "memory");
}

template <typename T>
void doNotOptimizeAway(T& val) {