Function TEST

test/cpp/eager/task_tests/hook_test.cc:59–133

}

TEST(RetainGrad, HookBeforeRetainGrad) {
  eager_test::InitEnv(phi::CPUPlace());

  // Prepare Inputs
  std::vector<paddle::Tensor> target_tensors;
  phi::DDim ddim = common::make_ddim({4, 16, 16, 32});

  // Create Target Tensor
  paddle::Tensor tensor =
      eager_test::CreateTensorWithValue(ddim,
                                        phi::CPUPlace(),
                                        phi::DataType::FLOAT32,
                                        phi::DataLayout::NCHW,
                                        1.0 /*value*/,
                                        false /*is_leaf*/);
  target_tensors.emplace_back(std::move(tensor));
  paddle::Tensor& target_tensor = target_tensors[0];

  // Create ScaleNode
  auto scale_node_ptr = std::make_shared<GradNodeScale>(1, 1);
  scale_node_ptr->SetAttributes_scale(5.0 /*scale*/);

  // Set grad in/out meta for node0
  scale_node_ptr->SetDefaultGradInOutMeta();

  // Connect Input Tensor and ScaleNode via AutoGradMeta
  // Apply RetainGrad
  {
    // ScaleNode Hook: +3

    auto auto_grad_meta = std::make_shared<AutogradMeta>();
    auto_grad_meta->SetGradNode(
        std::dynamic_pointer_cast<GradNodeBase>(scale_node_ptr));
    auto_grad_meta->SetSingleOutRankWithSlot(0, 0);
    auto_grad_meta->SetStopGradient(false);
    target_tensor.set_autograd_meta(
        std::dynamic_pointer_cast<paddle::AbstractAutogradMeta>(
            auto_grad_meta));

    egr_utils_api::RegisterGradientHookForTensor(target_tensor, hook_function);
    egr_utils_api::RetainGradForTensor(
        target_tensor);  // result: 1.0 + 3.0 = 4.0
    egr_utils_api::RetainGradForTensor(
        target_tensor);  // result: 1.0 + 3.0 = 4.0
  }

  // Retain Grad for leaf tensor1
  paddle::Tensor leaf_tensor = paddle::Tensor();
  {
    // AccumulationNode Hook: +3
    auto tmp_tensor0 = paddle::Tensor();
    auto auto_grad_meta = EagerUtils::autograd_meta(&tmp_tensor0);

    auto acc_node_ptr = std::make_shared<GradNodeAccumulation>(tmp_tensor0);

    auto_grad_meta->SetStopGradient(false);
    auto_grad_meta->SetGradNode(acc_node_ptr);
    auto_grad_meta->SetSingleOutRankWithSlot(0, 0);