CUDAFunctions.cpp

// Copyright (c) 2026 PaddlePaddle Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include <c10/cuda/CUDAFunctions.h>

namespace c10::cuda {

c10::DeviceIndex device_count() {
#if defined(PADDLE_WITH_CUDA) || defined(PADDLE_WITH_HIP)
  return phi::backends::gpu::GetGPUDeviceCount();
#else
  // Return 0 instead of throwing to match PyTorch API semantics
  // at::cuda::is_available() relies on this returning 0/false
  return 0;
#endif
}

void device_synchronize() {
#if defined(PADDLE_WITH_CUDA) || defined(PADDLE_WITH_HIP)
  int curr_device_id = paddle::platform::GetCurrentDeviceId();
  paddle::platform::SetDeviceId(curr_device_id);
#ifdef PADDLE_WITH_HIP
  PADDLE_ENFORCE_GPU_SUCCESS(hipDeviceSynchronize());
#else
  PADDLE_ENFORCE_GPU_SUCCESS(cudaDeviceSynchronize());
#endif
#else
  PADDLE_THROW(common::errors::Unavailable(
      "Paddle is not compiled with CUDA. Cannot visit device synchronize."));
#endif
}

}  // namespace c10::cuda