Method load_tensor_shared

src/serialization/impl/serializer_oss.cpp:691–738

}

std::shared_ptr<DeviceTensorND> GraphLoaderOSS::OprLoadContextImpl::load_tensor_shared(
        bool copy_immediatly) {
    mgb_assert(
            m_current_opr->tensors() &&
            m_cur_opr_tensor_cnt < m_current_opr->tensors()->size());
    auto tensor = m_current_opr->tensors()->Get(m_cur_opr_tensor_cnt++);
    auto comp_node = load_comp_node(tensor->comp_node());
    auto layout = load_tensor_layout(tensor);
    mgb_assert(tensor->data_size());
    if (m_loader->m_shared_tensor_map.size() <= m_cur_shared_tensor_idx) {
        m_loader->m_shared_tensor_map.resize(m_cur_shared_tensor_idx + 5);
    }
    auto&& sh_reg = m_loader->m_shared_tensor_map.at(m_cur_shared_tensor_idx++);
    auto&& sh_ptr_ref = sh_reg.second[comp_node.mem_node()];
    if (sh_ptr_ref) {
        // cached tensor value is valid so we can reuse it
        load_tensor_value(nullptr, layout, tensor);
        if (sh_ptr_ref->comp_node() == comp_node)
            return sh_ptr_ref;
        // same mem node but different comp node, change comp node and share
        // value
        auto ret = std::make_shared<DeviceTensorND>(*sh_ptr_ref);
        ret->comp_node(comp_node);
        return ret;
    }
    if (tensor->name()) {
        sh_reg.first = tensor->name()->str();
    }

    if (comp_node.mem_node() == CompNode::default_cpu().mem_node() || copy_immediatly) {
        // directly forward CPU memory
        HostTensorND hv{comp_node};
        load_tensor_value(&hv, layout, tensor);
        sh_ptr_ref = std::make_shared<DeviceTensorND>();
        if (comp_node.mem_node() == CompNode::default_cpu().mem_node()) {
            *sh_ptr_ref = DeviceTensorND::make_proxy(hv);
        } else {
            mgb_assert(copy_immediatly);
            sh_ptr_ref->comp_node(comp_node).copy_from(hv).sync();
        }
    } else {
        // use lazy load for non-CPU devices
        HostTensorND hv{CompNode::default_cpu()};
        load_tensor_value(&hv, layout, tensor);
        sh_ptr_ref = m_device_value_loader.make(comp_node, std::move(hv));
    }
    return sh_ptr_ref;
}

Metadata GraphLoaderOSS::OprLoadContextImpl::load_metadata() {
    const auto* fbmeta = m_loader->m_graph->metadata();