Common: improve native clock.

src/common/x64/native_clock.h

@@ -3,6 +3,7 @@
 
 #pragma once
 
+#include <atomic>
 #include "common/wall_clock.h"
 
 namespace Common {
@@ -28,13 +29,9 @@ public:
 private:
     u64 GetRTSC();
 
-    union alignas(16) TimePoint {
-        TimePoint() : pack{} {}
-        u128 pack{};
-        struct Inner {
-            u64 last_measure{};
-            u64 accumulated_ticks{};
-        } inner;
+    struct alignas(16) TimePoint {
+        u64 last_measure{};
+        u64 accumulated_ticks{};
     };
 
     /// value used to reduce the native clocks accuracy as some apss rely on
@@ -42,7 +39,7 @@ private:
     /// be higher.
     static constexpr u64 inaccuracy_mask = ~(UINT64_C(0x400) - 1);
 
-    TimePoint time_point;
+    std::atomic<TimePoint> time_point;
     // factors
     u64 clock_rtsc_factor{};
     u64 cpu_rtsc_factor{};