梯度下降的代码在哪里？

该实现进一步涉及本机c
++代码。这是

ApplyGradientDescent

core/kernels/training_ops_gpu.cu.cc

template <typename T>struct ApplyGradientDescent<GPUDevice, T> {  void operator()(const GPUDevice& d, typename TTypes<T>::Flat var,       typename TTypes<T>::ConstScalar lr,       typename TTypes<T>::ConstFlat grad) {    Eigen::array<typename TTypes<T>::Tensor::Index, 1> bcast;    bcast[0] = grad.dimension(0);    Eigen::Sizes<1> single;    var.device(d) -= lr.reshape(single).broadcast(bcast) * grad;  }};

CPU实现在此处（

core/kernels/training_ops.cc

template <typename T>struct ApplyGradientDescent<CPUDevice, T> {  void operator()(const CPUDevice& d, typename TTypes<T>::Flat var,       typename TTypes<T>::ConstScalar lr,       typename TTypes<T>::ConstFlat grad) {    var.device(d) -= grad * lr();  }};