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diff --git a/src/core/host_timing.h b/src/core/host_timing.h
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+++ b/src/core/host_timing.h
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+// Copyright 2020 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <atomic>
+#include <chrono>
+#include <functional>
+#include <memory>
+#include <mutex>
+#include <optional>
+#include <string>
+#include <thread>
+#include <vector>
+
+#include "common/common_types.h"
+#include "common/spin_lock.h"
+#include "common/thread.h"
+#include "common/threadsafe_queue.h"
+#include "common/wall_clock.h"
+#include "core/hardware_properties.h"
+
+namespace Core::HostTiming {
+
+/// A callback that may be scheduled for a particular core timing event.
+using TimedCallback = std::function<void(u64 userdata, s64 cycles_late)>;
+
+/// Contains the characteristics of a particular event.
+struct EventType {
+    EventType(TimedCallback&& callback, std::string&& name)
+        : callback{std::move(callback)}, name{std::move(name)} {}
+
+    /// The event's callback function.
+    TimedCallback callback;
+    /// A pointer to the name of the event.
+    const std::string name;
+};
+
+/**
+ * This is a system to schedule events into the emulated machine's future. Time is measured
+ * in main CPU clock cycles.
+ *
+ * To schedule an event, you first have to register its type. This is where you pass in the
+ * callback. You then schedule events using the type id you get back.
+ *
+ * The int cyclesLate that the callbacks get is how many cycles late it was.
+ * So to schedule a new event on a regular basis:
+ * inside callback:
+ *   ScheduleEvent(periodInCycles - cyclesLate, callback, "whatever")
+ */
+class CoreTiming {
+public:
+    CoreTiming();
+    ~CoreTiming();
+
+    CoreTiming(const CoreTiming&) = delete;
+    CoreTiming(CoreTiming&&) = delete;
+
+    CoreTiming& operator=(const CoreTiming&) = delete;
+    CoreTiming& operator=(CoreTiming&&) = delete;
+
+    /// CoreTiming begins at the boundary of timing slice -1. An initial call to Advance() is
+    /// required to end slice - 1 and start slice 0 before the first cycle of code is executed.
+    void Initialize();
+
+    /// Tears down all timing related functionality.
+    void Shutdown();
+
+    /// Pauses/Unpauses the execution of the timer thread.
+    void Pause(bool is_paused);
+
+    /// Pauses/Unpauses the execution of the timer thread and waits until paused.
+    void SyncPause(bool is_paused);
+
+    /// Checks if core timing is running.
+    bool IsRunning() const;
+
+    /// Checks if the timer thread has started.
+    bool HasStarted() const {
+        return has_started;
+    }
+
+    /// Checks if there are any pending time events.
+    bool HasPendingEvents() const;
+
+    /// Schedules an event in core timing
+    void ScheduleEvent(s64 ns_into_future, const std::shared_ptr<EventType>& event_type,
+                       u64 userdata = 0);
+
+    void UnscheduleEvent(const std::shared_ptr<EventType>& event_type, u64 userdata);
+
+    /// We only permit one event of each type in the queue at a time.
+    void RemoveEvent(const std::shared_ptr<EventType>& event_type);
+
+    void AddTicks(std::size_t core_index, u64 ticks);
+
+    void ResetTicks(std::size_t core_index);
+
+    /// Returns current time in emulated CPU cycles
+    u64 GetCPUTicks() const;
+
+    /// Returns current time in emulated in Clock cycles
+    u64 GetClockTicks() const;
+
+    /// Returns current time in microseconds.
+    std::chrono::microseconds GetGlobalTimeUs() const;
+
+    /// Returns current time in nanoseconds.
+    std::chrono::nanoseconds GetGlobalTimeNs() const;
+
+    /// Checks for events manually and returns time in nanoseconds for next event, threadsafe.
+    std::optional<u64> Advance();
+
+private:
+    struct Event;
+
+    /// Clear all pending events. This should ONLY be done on exit.
+    void ClearPendingEvents();
+
+    static void ThreadEntry(CoreTiming& instance);
+    void ThreadLoop();
+
+    std::unique_ptr<Common::WallClock> clock;
+
+    u64 global_timer = 0;
+
+    std::chrono::nanoseconds start_point;
+
+    // The queue is a min-heap using std::make_heap/push_heap/pop_heap.
+    // We don't use std::priority_queue because we need to be able to serialize, unserialize and
+    // erase arbitrary events (RemoveEvent()) regardless of the queue order. These aren't
+    // accomodated by the standard adaptor class.
+    std::vector<Event> event_queue;
+    u64 event_fifo_id = 0;
+
+    std::shared_ptr<EventType> ev_lost;
+    Common::Event event{};
+    Common::SpinLock basic_lock{};
+    Common::SpinLock advance_lock{};
+    std::unique_ptr<std::thread> timer_thread;
+    std::atomic<bool> paused{};
+    std::atomic<bool> paused_set{};
+    std::atomic<bool> wait_set{};
+    std::atomic<bool> shutting_down{};
+    std::atomic<bool> has_started{};
+
+    std::array<std::atomic<u64>, Core::Hardware::NUM_CPU_CORES> ticks_count{};
+};
+
+/// Creates a core timing event with the given name and callback.
+///
+/// @param name     The name of the core timing event to create.
+/// @param callback The callback to execute for the event.
+///
+/// @returns An EventType instance representing the created event.
+///
+std::shared_ptr<EventType> CreateEvent(std::string name, TimedCallback&& callback);
+
+} // namespace Core::HostTiming