feat(memory): add generic IMemoryAllocator and MemoryPool

Refactored Arena, DynamicArena, FreeList, and Stack to implement the new IMemoryAllocator<TSelf, TOpts> interface, standardizing allocation and free methods. Introduced MemoryPool<T, TOpts> for allocator lifetime management and AllocationHandle access. Updated Program.cs to use MemoryPool, replacing AllocationManager. Minor project file updates included.

Misaki.HighPerformance.LowLevel/Buffer/Arena.cs

@@ -7,8 +7,18 @@ namespace Misaki.HighPerformance.LowLevel.Buffer;
 /// A memory management structure that allocates and resets memory blocks with specified alignment.
 /// </summary>
 [StructLayout(LayoutKind.Explicit, Size = 64)] // Cache line aligned to prevent false sharing
-public unsafe struct Arena : IDisposable
+public unsafe struct Arena : IMemoryAllocator<Arena, Arena.CreateOptions>
 {
+    public struct CreateOptions
+    {
+        public nuint size;
+    }
+
+    public static Arena Create(in CreateOptions opts)
+    {
+        return new Arena(opts.size);
+    }
+
     [FieldOffset(0)]
     private byte* _buffer;
     [FieldOffset(8)]
@@ -82,6 +92,11 @@ public unsafe struct Arena : IDisposable
         return ptr;
     }
 
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public readonly void Free(void* ptr)
+    {
+    }
+
     /// <summary>
     /// Resets the arena.
     /// </summary>

Misaki.HighPerformance.LowLevel/Buffer/DynamicArena.cs

@@ -6,8 +6,18 @@ namespace Misaki.HighPerformance.LowLevel.Buffer;
 /// A dynamic memory management structure that automatically grows by creating linked arenas when more space is needed.
 /// </summary>
 [StructLayout(LayoutKind.Explicit, Size = 128)]
-public unsafe struct DynamicArena : IDisposable
+public unsafe struct DynamicArena : IMemoryAllocator<DynamicArena, DynamicArena.CreateOptions>
 {
+    public struct CreateOptions
+    {
+        public uint initialSize;
+    }
+
+    public static DynamicArena Create(in CreateOptions options)
+    {
+        return new DynamicArena(options.initialSize);
+    }
+
     [StructLayout(LayoutKind.Sequential)]
     private struct ArenaNode
     {
@@ -133,6 +143,10 @@ public unsafe struct DynamicArena : IDisposable
         return result;
     }
 
+    public readonly void Free(void* ptr)
+    {
+    }
+
     /// <summary>
     /// Resets all arenas in the chain.
     /// </summary>

Misaki.HighPerformance.LowLevel/Buffer/FreeList.cs

@@ -7,8 +7,20 @@ namespace Misaki.HighPerformance.LowLevel.Buffer;
 /// A variable-size allocator that uses per-thread caches for the hot path and a remote-free queue for cross-thread deallocation.
 /// </summary>
 [StructLayout(LayoutKind.Sequential)]
-public unsafe struct FreeList : IDisposable
+public unsafe struct FreeList : IMemoryAllocator<FreeList, FreeList.CreationOpts>
 {
+    public struct CreationOpts
+    {
+        public nuint alignment;
+        public nuint chunkSize;
+        public int maxConcurrencyLevel;
+    }
+
+    public static FreeList Create(in CreationOpts opts)
+    {
+        return new FreeList(opts.alignment, opts.chunkSize, opts.maxConcurrencyLevel);
+    }
+
     [StructLayout(LayoutKind.Sequential)]
     private struct FreeNode
     {

Misaki.HighPerformance.LowLevel/Buffer/IAllocator.cs

@@ -109,3 +109,12 @@ public interface IAllocator
         get;
     }
 }
+
+public unsafe interface IMemoryAllocator<TSelf, TOpts> : IDisposable
+    where TSelf : unmanaged, IMemoryAllocator<TSelf, TOpts>
+{
+    static abstract TSelf Create(in TOpts opts);
+
+    void* Allocate(nuint size, nuint alignment, AllocationOption option = AllocationOption.None);
+    void Free(void* ptr);
+}

Misaki.HighPerformance.LowLevel/Buffer/MemoryPool.cs

@@ -0,0 +1,74 @@
+using Misaki.HighPerformance.LowLevel.Utilities;
+
+namespace Misaki.HighPerformance.LowLevel.Buffer;
+
+public unsafe struct MemoryPool<T, TOpts> : IDisposable
+    where T : unmanaged, IMemoryAllocator<T, TOpts>
+{
+    private T* _pAllocator;
+    private AllocationHandle _allocationHandle;
+
+    public readonly ref T Allocator => ref *_pAllocator;
+    public readonly AllocationHandle AllocationHandle => _allocationHandle;
+
+    public MemoryPool(in TOpts opts)
+    {
+        _pAllocator = (T*)Malloc((nuint)sizeof(T));
+        *_pAllocator = T.Create(opts);
+
+        _allocationHandle = new AllocationHandle
+        {
+            State = _pAllocator,
+            Alloc = &Allocate,
+            Realloc = &Reallocate,
+            Free = &Free,
+            IsValid = null
+        };
+    }
+
+    private static void* Allocate(void* pAllocator, nuint size, nuint alignment, AllocationOption allocationOption, MemoryHandle* pHandle)
+    {
+        return ((T*)pAllocator)->Allocate(size, alignment, allocationOption);
+    }
+
+    private static void* Reallocate(void* pAllocator, void* ptr, nuint oldSize, nuint newSize, nuint alignment, AllocationOption allocationOption, MemoryHandle* pHandle)
+    {
+        if (ptr == null)
+        {
+            return Allocate(pAllocator, newSize, alignment, allocationOption, pHandle);
+        }
+
+        MemoryHandle newHandle;
+        var newPtr = Allocate(pAllocator, newSize, alignment, allocationOption, &newHandle);
+        if (newPtr == null)
+        {
+            return null;
+        }
+
+        MemCpy(newPtr, ptr, Math.Min(oldSize, newSize));
+        Free(pAllocator, ptr, *pHandle);
+
+        *pHandle = newHandle;
+        return newPtr;
+    }
+
+    private static void Free(void* pAllocator, void* ptr, MemoryHandle handle)
+    {
+        ((T*)pAllocator)->Free(ptr);
+    }
+
+    public void Dispose()
+    {
+        if (_pAllocator == null)
+        {
+            return;
+        }
+
+        _pAllocator->Dispose();
+
+        MemoryUtility.Free(_pAllocator);
+
+        _pAllocator = null;
+        _allocationHandle = default;
+    }
+}

Misaki.HighPerformance.LowLevel/Buffer/Stack.cs

@@ -1,3 +1,4 @@
+using Misaki.HighPerformance.LowLevel.Utilities;
 using System.Runtime.CompilerServices;
 
 namespace Misaki.HighPerformance.LowLevel.Buffer;
@@ -18,7 +19,7 @@ public unsafe partial struct Stack
 
         for (var i = 0; i < s_stackCount; i++)
         {
-            Free(s_pStackBuffers[i]);
+            MemoryUtility.Free(s_pStackBuffers[i]);
         }
     }
 }
@@ -28,8 +29,18 @@ public unsafe partial struct Stack
 /// blocks within a preallocated buffer.
 /// </summary>
 /// <remarks>This is not a thread-safe implementation.</remarks>
-public unsafe partial struct Stack : IDisposable
+public unsafe partial struct Stack : IMemoryAllocator<Stack, Stack.CreationOpts>
 {
+    public struct CreationOpts
+    {
+        public nuint size;
+    }
+
+    public static Stack Create(in CreationOpts opts)
+    {
+        return new Stack(opts.size);
+    }
+
     private const nuint _DEFAULT_SIZE = 1024 * 1024; // 1MB
 
     public readonly ref struct Scope : IDisposable
@@ -211,6 +222,10 @@ public unsafe partial struct Stack : IDisposable
         return ptr;
     }
 
+    public readonly void Free(void* ptr)
+    {
+    }
+
     /// <summary>
     /// Resets the internal offset to its initial position.
     /// </summary>