device.ipp

/* VecMem project, part of the ACTS project (R&D line)
 *
 * (c) 2023-2025 CERN for the benefit of the ACTS project
 *
 * Mozilla Public License Version 2.0
 */
#pragma once
 
// Local include(s).
#include "vecmem/edm/details/device_traits.hpp"
#include "vecmem/edm/details/schema_traits.hpp"
#include "vecmem/memory/device_atomic_ref.hpp"
 
// System include(s).
#include <cassert>
 
namespace vecmem {
namespace edm {
 
template <typename... VARTYPES, template <typename> class INTERFACE>
VECMEM_HOST_AND_DEVICE device<schema<VARTYPES...>, INTERFACE>::device(
    const view<schema_type>& view)
    : m_capacity{view.capacity()},
      m_size{details::device_size_pointer<vecmem::details::disjunction_v<
          type::details::is_jagged_vector<VARTYPES>...>>::get(view.size())},
      m_data{view.variables()} {
 
    // Check that all variables have the correct capacities.
    assert(details::device_capacities_match<VARTYPES...>(
        m_capacity, m_data, std::index_sequence_for<VARTYPES...>{}));
}
 
template <typename... VARTYPES, template <typename> class INTERFACE>
VECMEM_HOST_AND_DEVICE auto device<schema<VARTYPES...>, INTERFACE>::size() const
    -> size_type {
 
    // Check that all variables have the correct capacities.
    assert(details::device_capacities_match<VARTYPES...>(
        m_capacity, m_data, std::index_sequence_for<VARTYPES...>{}));
 
    return (m_size == nullptr ? m_capacity : *m_size);
}
 
template <typename... VARTYPES, template <typename> class INTERFACE>
VECMEM_HOST_AND_DEVICE auto device<schema<VARTYPES...>, INTERFACE>::capacity()
    const -> size_type {
 
    // Check that all variables have the correct capacities.
    assert(details::device_capacities_match<VARTYPES...>(
        m_capacity, m_data, std::index_sequence_for<VARTYPES...>{}));
 
    return m_capacity;
}
 
template <typename... VARTYPES, template <typename> class INTERFACE>
VECMEM_HOST_AND_DEVICE auto
device<schema<VARTYPES...>, INTERFACE>::push_back_default() -> size_type {
 
    // There must be no jagged vector variables for this to work.
    static_assert(!vecmem::details::disjunction<
                      type::details::is_jagged_vector<VARTYPES>...>::value,
                  "Containers with jagged vector variables cannot be resized!");
    // There must be at least one vector variable in the container.
    static_assert(vecmem::details::disjunction<
                      type::details::is_vector<VARTYPES>...>::value,
                  "This function requires at least one vector variable.");
    // This can only be done on a resizable container.
    assert(m_size != nullptr);
    // Check that all variables have the correct capacities.
    assert(details::device_capacities_match<VARTYPES...>(
        m_capacity, m_data, std::index_sequence_for<VARTYPES...>{}));
 
    // Increment the size of the container at first. So that we would "claim"
    // the index from other threads.
    device_atomic_ref<size_type> asize(*m_size);
    const size_type index = asize.fetch_add(1u);
    assert(index < m_capacity);
 
    // Construct the new elements in all of the vector variables.
    construct_default(index, std::index_sequence_for<VARTYPES...>{});
 
    // Return the position of the new variable(s).
    return index;
}
 
template <typename... VARTYPES, template <typename> class INTERFACE>
VECMEM_HOST_AND_DEVICE auto device<schema<VARTYPES...>, INTERFACE>::push_back(
    const object_type& element) -> size_type {
 
    // Add a new default element to the container.
    const size_type index = push_back_default();
 
    // Set it to the given value.
    at(index) = element;
 
    // Return the position of the new variable(s).
    return index;
}
 
template <typename... VARTYPES, template <typename> class INTERFACE>
template <std::size_t INDEX>
VECMEM_HOST_AND_DEVICE
    typename details::device_type_at<INDEX, VARTYPES...>::return_type
    device<schema<VARTYPES...>, INTERFACE>::get() {
 
    return details::device_get<tuple_element_t<INDEX, tuple<VARTYPES...>>>::get(
        vecmem::get<INDEX>(m_data));
}
 
template <typename... VARTYPES, template <typename> class INTERFACE>
template <std::size_t INDEX>
VECMEM_HOST_AND_DEVICE
    typename details::device_type_at<INDEX, VARTYPES...>::const_return_type
    device<schema<VARTYPES...>, INTERFACE>::get() const {
 
    return details::device_get<tuple_element_t<INDEX, tuple<VARTYPES...>>>::get(
        vecmem::get<INDEX>(m_data));
}
 
template <typename... VARTYPES, template <typename> class INTERFACE>
VECMEM_HOST_AND_DEVICE
    typename device<schema<VARTYPES...>, INTERFACE>::proxy_type
    device<schema<VARTYPES...>, INTERFACE>::at(size_type index) {
 
    // Make sure that the index is within bounds.
    assert(index < size());
 
    // Use the unprotected function.
    return this->operator[](index);
}
 
template <typename... VARTYPES, template <typename> class INTERFACE>
VECMEM_HOST_AND_DEVICE
    typename device<schema<VARTYPES...>, INTERFACE>::const_proxy_type
    device<schema<VARTYPES...>, INTERFACE>::at(size_type index) const {
 
    // Make sure that the index is within bounds.
    assert(index < size());
 
    // Use the unprotected function.
    return this->operator[](index);
}
 
template <typename... VARTYPES, template <typename> class INTERFACE>
VECMEM_HOST_AND_DEVICE
    typename device<schema<VARTYPES...>, INTERFACE>::proxy_type
    device<schema<VARTYPES...>, INTERFACE>::operator[](size_type index) {
 
    // Create the proxy.
    return proxy_type{*this, index};
}
 
template <typename... VARTYPES, template <typename> class INTERFACE>
VECMEM_HOST_AND_DEVICE
    typename device<schema<VARTYPES...>, INTERFACE>::const_proxy_type
    device<schema<VARTYPES...>, INTERFACE>::operator[](size_type index) const {
 
    // Create the proxy.
    return const_proxy_type{*this, index};
}
 
template <typename... VARTYPES, template <typename> class INTERFACE>
VECMEM_HOST_AND_DEVICE auto device<schema<VARTYPES...>, INTERFACE>::variables()
    -> tuple_type& {
 
    return m_data;
}
 
template <typename... VARTYPES, template <typename> class INTERFACE>
VECMEM_HOST_AND_DEVICE auto device<schema<VARTYPES...>, INTERFACE>::variables()
    const -> const tuple_type& {
 
    return m_data;
}
 
template <typename... VARTYPES, template <typename> class INTERFACE>
template <std::size_t INDEX, std::size_t... Is>
VECMEM_HOST_AND_DEVICE void
device<schema<VARTYPES...>, INTERFACE>::construct_default(
    size_type index, std::index_sequence<INDEX, Is...>) const {
 
    // Construct the new element in this variable, if it's a vector.
    construct_vector(index, vecmem::get<INDEX>(m_data));
    // Continue the recursion.
    construct_default(index, std::index_sequence<Is...>{});
}
 
template <typename... VARTYPES, template <typename> class INTERFACE>
VECMEM_HOST_AND_DEVICE void
device<schema<VARTYPES...>, INTERFACE>::construct_default(
    size_type, std::index_sequence<>) const {
    // The terminal node doesn't need to do anything.
}
 
template <typename... VARTYPES, template <typename> class INTERFACE>
template <typename T>
VECMEM_HOST_AND_DEVICE void
device<schema<VARTYPES...>, INTERFACE>::construct_vector(size_type, T&) const {
    // Nothing is done for non-vector variables.
}
 
template <typename... VARTYPES, template <typename> class INTERFACE>
template <typename T>
VECMEM_HOST_AND_DEVICE void
device<schema<VARTYPES...>, INTERFACE>::construct_vector(
    size_type index, device_vector<T>& vec) const {
 
    vec.construct(index, {});
}
 
}  // namespace edm
}  // namespace vecmem