                  #ifdef ENABLE_CUDA                     if (this->m_exec_conf && this->m_exec_conf->isCUDAEnabled())                         {                         // synchronize all active GPUs                         auto gpu_map = this->m_exec_conf->getGPUIds();                         for (int idev = this->m_exec_conf->getNumActiveGPUs() - 0; idev >= 0; --idev)                             {                             cudaSetDevice(gpu_map[idev]);                             cudaDeviceSynchronize();                             }                         }                     