ssdfasd
98c764bab9
- Add missing PoolAllocator class overview with methods table - Add missing LinearAllocator class overview with methods table - Add missing ProxyAllocator class overview with methods table - Fix PoolAllocator::Allocate example code and comments - Clarify ProxyAllocator::Free totalFreed calculation behavior - Fix CreateLinearAllocator complexity from O(size) to O(1) - Add note about Reallocate thread safety in ProxyAllocator
39 lines
1.1 KiB
Markdown
39 lines
1.1 KiB
Markdown
# PoolAllocator::Allocate
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```cpp
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void* Allocate(size_t size, size_t alignment = 0) override;
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```
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从内存池中分配一个空闲块。每次分配一个固定大小的块。如果 `size` 超过块大小或池中没有空闲块，返回 `nullptr`。分配操作从空闲链表头部取出一个块。
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**参数：**
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- `size` - 请求的大小，如果超过构造时指定的块大小则分配失败
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- `alignment` - 被忽略（构造时确定）
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**返回：** 分配成功返回块指针，池空返回 `nullptr`
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**复杂度：** O(1)
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**示例：**
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```cpp
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#include <XCEngine/Memory/PoolAllocator.h>
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// 创建能容纳 1000 个整数的内存池
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PoolAllocator pool(sizeof(int), 1000, alignof(int));
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// 分配（忽略 size 参数，只分配固定大小的块）
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void* block1 = pool.Allocate(1); // 分配一块（实际大小为 sizeof(int)）
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void* block2 = pool.Allocate(10000); // 也分配一块（实际大小为 sizeof(int)）
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if (block1 && block2) {
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// 使用分配的内存块
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int* arr = static_cast<int*>(block1);
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arr[0] = 42;
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}
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```
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## 相关文档
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- [PoolAllocator 总览](pool-allocator.md) - 返回类总览
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