Add NCE code

src/Ryujinx.Cpu/Nce/NceNativeInterface.cs

@@ -0,0 +1,55 @@
+using System;
+using System.Runtime.InteropServices;
+
+namespace Ryujinx.Cpu.Nce
+{
+    static class NceNativeInterface
+    {
+        private delegate ulong GetTickCounterDelegate();
+        private delegate bool SuspendThreadHandlerDelegate();
+        private static GetTickCounterDelegate _getTickCounter;
+        private static SuspendThreadHandlerDelegate _suspendThreadHandler;
+        private static IntPtr _getTickCounterPtr;
+        private static IntPtr _suspendThreadHandlerPtr;
+
+        [ThreadStatic]
+        private static NceExecutionContext _context;
+
+        [ThreadStatic]
+        private static ITickSource _tickSource;
+
+        static NceNativeInterface()
+        {
+            _getTickCounter = GetTickCounter;
+            _suspendThreadHandler = SuspendThreadHandler;
+            _getTickCounterPtr = Marshal.GetFunctionPointerForDelegate(_getTickCounter);
+            _suspendThreadHandlerPtr = Marshal.GetFunctionPointerForDelegate(_suspendThreadHandler);
+        }
+
+        public static void RegisterThread(NceExecutionContext context, ITickSource tickSource)
+        {
+            _context = context;
+            _tickSource = tickSource;
+        }
+
+        public static ulong GetTickCounter()
+        {
+            return _tickSource.Counter;
+        }
+
+        public static bool SuspendThreadHandler()
+        {
+            return _context.OnInterrupt();
+        }
+
+        public static IntPtr GetTickCounterAccessFunctionPointer()
+        {
+            return _getTickCounterPtr;
+        }
+
+        public static IntPtr GetSuspendThreadHandlerFunctionPointer()
+        {
+            return _suspendThreadHandlerPtr;
+        }
+    }
+}