Files
2026-07-13 12:40:42 +08:00

49 lines
1.7 KiB
C++

// Copyright (c) 2022 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 "paddle/phi/kernels/bce_loss_grad_kernel.h"
#include <algorithm> // for max
#include "paddle/phi/backends/cpu/cpu_context.h"
#include "paddle/phi/core/kernel_registry.h"
namespace phi {
template <typename T, typename Context>
void BCELossGradKernel(const Context& dev_ctx,
const DenseTensor& input,
const DenseTensor& label,
const DenseTensor& out_grad,
DenseTensor* input_grad) {
auto dx_data = dev_ctx.template Alloc<T>(input_grad);
auto dout_data = out_grad.data<T>();
auto x_data = input.data<T>();
auto label_data = label.data<T>();
int x_numel = static_cast<int>(input.numel());
// dx = dout * ((x - label)/(x - x^2))
for (int i = 0; i < x_numel; ++i) {
dx_data[i] =
dout_data[i] * ((x_data[i] - label_data[i]) /
std::max((static_cast<T>(1) - x_data[i]) * x_data[i],
static_cast<T>(1e-12)));
}
}
} // namespace phi
PD_REGISTER_KERNEL(
bce_loss_grad, CPU, ALL_LAYOUT, phi::BCELossGradKernel, float, double) {}