splits allocation for pten, test=develop · Pull Request !2760 · PaddlePaddle/Paddle

### PR changes

APIs

### Describe

本提交是方案二的主框架修改部分，定义了计算库分配器的接口规格：

```
class pten::Allocator {
 public:
  using DeleterType = std::function<void(Allocation*)>;
  using AllocationPtr = std::unique_ptr<Allocation, DeleterType>;

virtual ~Allocator() = default;
  virtual AllocationPtr Allocate(size_t bytes_size) = 0;

virtual bool IsAllocThreadSafe() const { return false; }
};
```
框架修改后的继承关系：
```
     _______________ _______________________________________
   |               |                                       |
   |   Allocator <---  Allocator <---  Strategy Allocators |
   |    * pten *   |               * fluid *               |
    --------------- ---------------------------------------

_______________ ____________________________________________________
   |               |                                                    |
   |   Allocation <---  Decorated Allocation <---  Strategy Allocations |
   |    * pten *   |                      * fluid *                     |
    --------------- ----------------------------------------------------
```
其中，pten 存放的是公共基类（接口类），供训推双方使用，并对原框架中用于装饰和策略的数据结构进行了更名。

GVPPaddlePaddle/Paddle

搜索帮助

GVP PaddlePaddle/Paddle