Move solution and projects to src

src/Ryujinx.Audio/Renderer/Utils/SpanMemoryManager.cs

@@ -0,0 +1,43 @@
+using System;
+using System.Buffers;
+using System.Runtime.InteropServices;
+
+namespace Ryujinx.Audio.Renderer.Utils
+{
+    public sealed unsafe class SpanMemoryManager<T> : MemoryManager<T>
+        where T : unmanaged
+    {
+        private readonly T* _pointer;
+        private readonly int _length;
+
+        public SpanMemoryManager(Span<T> span)
+        {
+            fixed (T* ptr = &MemoryMarshal.GetReference(span))
+            {
+                _pointer = ptr;
+                _length = span.Length;
+            }
+        }
+
+        public override Span<T> GetSpan() => new Span<T>(_pointer, _length);
+
+        public override MemoryHandle Pin(int elementIndex = 0)
+        {
+            if (elementIndex < 0 || elementIndex >= _length)
+            {
+                throw new ArgumentOutOfRangeException(nameof(elementIndex));
+            }
+
+            return new MemoryHandle(_pointer + elementIndex);
+        }
+
+        public override void Unpin() { }
+
+        protected override void Dispose(bool disposing) { }
+
+        public static Memory<T> Cast<TFrom>(Memory<TFrom> memory) where TFrom : unmanaged
+        {
+            return new SpanMemoryManager<T>(MemoryMarshal.Cast<TFrom, T>(memory.Span)).Memory;
+        }
+    }
+}