Implement L4 Swiss map and benchmarks

src/Nitload.Common/HighPerformance/Memory/L4.CacheLine.cs

@@ -27,6 +27,8 @@ namespace Nitload.Common.HighPerformance.Memory
 
             internal const uint MaxBufferSize = 0xFFFFFFFF - 64U;
 
+            [FieldOffset(16)] internal AllocationState State;
+
             public static uint SizeOf { get; } = (uint)Unsafe.SizeOf<CacheLineMetadata>();
 
             #region tlsf linked list
@@ -43,20 +45,27 @@ namespace Nitload.Common.HighPerformance.Memory
             [FieldOffset(8)] public uint PositionMask;
             [FieldOffset(12)] public uint SizeMask;
 
-            #endregion
-
-            [FieldOffset(16)] internal AllocationState State;
-
+        #endregion
         }
 
 #pragma warning disable IDE0032
         [StructLayout(LayoutKind.Explicit, Size = 16)]
-        public struct Handle : IDisposable
+        public unsafe struct Handle : IDisposable
         {
 
             [FieldOffset(0)] private nuint _handle;
+
             [FieldOffset(8)] private nuint _reserved;
 
+            internal Handle(
+                     nuint handle,
+                     nuint reserved
+            )
+            {
+                _handle = handle;
+                _reserved = reserved;
+            }
+
             [Obsolete("You should not create a CacheLineHandle instance outside a L4", true)]
             public Handle() { }