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docs/api/memory/pool-allocator/free.md

@@ -0,0 +1,38 @@
+# PoolAllocator::Free
+
+```cpp
+void Free(void* ptr) override;
+```
+
+将内存块归还到空闲链表中。如果 `ptr` 为 `nullptr` 则无效果。释放操作将块插入空闲链表头部。必须传入从此池分配的指针，传入外部指针会导致未定义行为。
+
+**参数：**
+- `ptr` - 指向要释放的内存块
+
+**返回：** 无
+
+**复杂度：** O(1)
+
+**示例：**
+
+```cpp
+#include <XCEngine/Memory/PoolAllocator.h>
+
+PoolAllocator pool(sizeof(int), 100);
+
+void* block = pool.Allocate();
+if (block) {
+    int* num = static_cast<int*>(block);
+    *num = 123;
+    
+    pool.Free(block); // 归还到空闲链表
+    block = nullptr;
+}
+
+// 检查空闲块数量
+size_t freeCount = pool.GetFreeBlockCount();
+```
+
+## 相关文档
+
+- [PoolAllocator 总览](pool-allocator.md) - 返回类总览