Conditionally import CUDAGraph based on CUDA compilation

Author: yuanlehome

fastdeploy/model_executor/graph_optimization/cudagraph_piecewise_backend.py

@@ -93,9 +93,10 @@ def __init__(self, fd_config: FDConfig, runnable: Callable):
         self.real_shape_to_captured_size = fd_config.graph_opt_config.real_shape_to_captured_size
         self.unique_memory_pool_id = None
         if self.fd_config.graph_opt_config.use_unique_memory_pool:
-            from paddle.base.core import CUDAGraph
+            if paddle.is_compiled_with_cuda():
+                from paddle.base.core import CUDAGraph
 
-            self.unique_memory_pool_id = CUDAGraph.gen_new_memory_pool_id()
+                self.unique_memory_pool_id = CUDAGraph.gen_new_memory_pool_id()
         self._create_entry_dict()
 
         self.cuda_graph_manager = None