New GPFifo and fast guest constant buffer updates (#1400)

* Add new structures from official docs, start migrating GPFifo

* Finish migration to new GPFifo processor

* Implement fast constant buffer data upload

* Migrate to new GPFifo class

* XML docs

Ryujinx.Graphics.Gpu/Engine/MME/Macro.cs

@@ -0,0 +1,69 @@
+using Ryujinx.Graphics.Gpu.State;
+
+namespace Ryujinx.Graphics.Gpu.Engine.MME
+{
+    /// <summary>
+    /// GPU macro program.
+    /// </summary>
+    struct Macro
+    {
+        /// <summary>
+        /// Word offset of the code on the code memory.
+        /// </summary>
+        public int Position { get; }
+
+        private bool _executionPending;
+        private int _argument;
+
+        private readonly MacroInterpreter _interpreter;
+
+        /// <summary>
+        /// Creates a new instance of the GPU cached macro program.
+        /// </summary>
+        /// <param name="position">Macro code start position</param>
+        public Macro(int position)
+        {
+            Position = position;
+
+            _executionPending = false;
+            _argument = 0;
+
+            _interpreter = new MacroInterpreter();
+        }
+
+        /// <summary>
+        /// Sets the first argument for the macro call.
+        /// </summary>
+        /// <param name="argument">First argument</param>
+        public void StartExecution(int argument)
+        {
+            _argument = argument;
+
+            _executionPending = true;
+        }
+
+        /// <summary>
+        /// Starts executing the macro program code.
+        /// </summary>
+        /// <param name="mme">Program code</param>
+        /// <param name="state">Current GPU state</param>
+        public void Execute(int[] mme, ShadowRamControl shadowCtrl, GpuState state)
+        {
+            if (_executionPending)
+            {
+                _executionPending = false;
+
+                _interpreter?.Execute(mme, Position, _argument, shadowCtrl, state);
+            }
+        }
+
+        /// <summary>
+        /// Pushes an argument to the macro call argument FIFO.
+        /// </summary>
+        /// <param name="argument">Argument to be pushed</param>
+        public void PushArgument(int argument)
+        {
+            _interpreter?.Fifo.Enqueue(argument);
+        }
+    }
+}