Scarfski/entt
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

memory: uses_allocator_construction_args pairs support

Browse Source
This commit is contained in:
Michele Caini
2022-02-23 00:19:55 +01:00
parent cdd029853b
commit cdaced4df6
3 changed files with 115 additions and 18 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
TODO
View File

@@ -4,7 +4,7 @@
* add examples (and credits) from @alanjfs :)
WIP:
* uses-allocator construction: dense map, compressed pair, any (with allocator support), cache, dispatcher, poly, ...
* uses-allocator construction: dense map, compressed pair, any (with allocator support), cache, dispatcher, poly, storage/map/allocate_unique (with uninitialized_construct_using_allocator/construct_at), ...
* add an ENTT_NOEXCEPT with args and use it to make ie compressed_pair conditionally noexcept
* process scheduler: reviews, use free lists internally
* runtime events (emitter)

85
src/entt/core/memory.hpp
View File

@@ -163,16 +163,78 @@ auto allocate_unique(Allocator &allocator, Args &&...args) {
return std::unique_ptr<Type, allocation_deleter<alloc>>{ptr, type_allocator};
}
/**
* @cond TURN_OFF_DOXYGEN
* Internal details not to be documented.
*/
namespace internal {
template<typename Type>
struct uses_allocator_construction {
template<typename Allocator, typename... Params>
static constexpr auto args(const Allocator &allocator, Params &&...params) ENTT_NOEXCEPT {
if constexpr(!std::uses_allocator_v<Type, Allocator> && std::is_constructible_v<Type, Params...>) {
return std::forward_as_tuple(std::forward<Params>(params)...);
} else {
static_assert(std::uses_allocator_v<Type, Allocator>, "Ill-formed request");
if constexpr(std::is_constructible_v<Type, std::allocator_arg_t, const Allocator &, Params...>) {
return std::tuple<std::allocator_arg_t, const Allocator &, Params &&...>(std::allocator_arg, allocator, std::forward<Params>(params)...);
} else {
static_assert(std::is_constructible_v<Type, Params..., const Allocator &>, "Ill-formed request");
return std::forward_as_tuple(std::forward<Params>(params)..., allocator);
}
}
}
};
template<typename Type, typename Other>
struct uses_allocator_construction<std::pair<Type, Other>> {
using type = std::pair<Type, Other>;
template<typename Allocator, typename First, typename Second>
static constexpr auto args(const Allocator &allocator, std::piecewise_construct_t, First &&first, Second &&second) ENTT_NOEXCEPT {
return std::make_tuple(
std::piecewise_construct,
std::apply([&allocator](auto &&...curr) { return uses_allocator_construction<Type>::args(allocator, std::forward<decltype(curr)>(curr)...); }, std::forward<First>(first)),
std::apply([&allocator](auto &&...curr) { return uses_allocator_construction<Other>::args(allocator, std::forward<decltype(curr)>(curr)...); }, std::forward<Second>(second)));
}
template<typename Allocator>
static constexpr auto args(const Allocator &allocator) ENTT_NOEXCEPT {
return uses_allocator_construction<type>::args(allocator, std::piecewise_construct, std::tuple<>{}, std::tuple<>{});
}
template<typename Allocator, typename First, typename Second>
static constexpr auto args(const Allocator &allocator, First &&first, Second &&second) ENTT_NOEXCEPT {
return uses_allocator_construction<type>::args(allocator, std::piecewise_construct, std::forward_as_tuple(std::forward<First>(first)), std::forward_as_tuple(std::forward<Second>(second)));
}
template<typename Allocator, typename First, typename Second>
static constexpr auto args(const Allocator &allocator, const std::pair<First, Second> &value) ENTT_NOEXCEPT {
return uses_allocator_construction<type>::args(allocator, std::piecewise_construct, std::forward_as_tuple(value.first), std::forward_as_tuple(value.second));
}
template<typename Allocator, typename First, typename Second>
static constexpr auto args(const Allocator &allocator, std::pair<First, Second> &&value) ENTT_NOEXCEPT {
return uses_allocator_construction<type>::args(allocator, std::piecewise_construct, std::forward_as_tuple(std::move(value.first)), std::forward_as_tuple(std::move(value.second)));
}
};
} // namespace internal
/**
* Internal details not to be documented.
* @endcond
*/
/**
* @brief Uses-allocator construction utility (waiting for C++20).
*
* Primarily intended for internal use. Prepares the argument list needed to
* create an object of a given type by means of uses-allocator construction.
*
* @warning
* Unlike the standard implementation, this utility does not differentiate
* between pair and non-pair types.
*
* @tparam Type Type to return arguments for.
* @tparam Allocator Type of allocator used to manage memory and elements.
* @tparam Args Types of arguments to use to construct the object.
@@ -182,18 +244,7 @@ auto allocate_unique(Allocator &allocator, Args &&...args) {
*/
template<typename Type, typename Allocator, typename... Args>
constexpr auto uses_allocator_construction_args(const Allocator &allocator, Args &&...args) ENTT_NOEXCEPT {
if constexpr(!std::uses_allocator_v<Type, Allocator> && std::is_constructible_v<Type, Args...>) {
return std::forward_as_tuple(std::forward<Args>(args)...);
} else {
static_assert(std::uses_allocator_v<Type, Allocator>, "Ill-formed request");
if constexpr(std::is_constructible_v<Type, std::allocator_arg_t, const Allocator &, Args...>) {
return std::tuple<std::allocator_arg_t, const Allocator &, Args &&...>(std::allocator_arg, allocator, std::forward<Args>(args)...);
} else {
static_assert(std::is_constructible_v<Type, Args..., const Allocator &>, "Ill-formed request");
return std::forward_as_tuple(std::forward<Args>(args)..., allocator);
}
}
return internal::uses_allocator_construction<Type>::args(allocator, std::forward<Args>(args)...);
}
/**
@@ -211,7 +262,7 @@ constexpr auto uses_allocator_construction_args(const Allocator &allocator, Args
*/
template<typename Type, typename Allocator, typename... Args>
constexpr Type make_obj_using_allocator(const Allocator &allocator, Args &&...args) {
return std::make_from_tuple<Type>(entt::uses_allocator_construction_args<Type>(allocator, std::forward<Args>(args)...));
return std::make_from_tuple<Type>(internal::uses_allocator_construction<Type>::args(allocator, std::forward<Args>(args)...));
}
} // namespace entt

46
test/entt/core/memory.cpp
View File

@@ -148,6 +148,52 @@ TEST(UsesAllocatorConstructionArgs, TrailingAllocatorConvention) {
ASSERT_EQ(std::get<0>(args), size);
}
TEST(UsesAllocatorConstructionArgs, PairPiecewiseConstruct) {
const auto size = 42u;
const auto tup = std::make_tuple(size);
const auto args = entt::uses_allocator_construction_args<std::pair<int, std::vector<int>>>(std::allocator<int>{}, std::piecewise_construct, std::make_tuple(3), tup);
static_assert(std::tuple_size_v<decltype(args)> == 3u);
static_assert(std::is_same_v<decltype(args), const std::tuple<std::piecewise_construct_t, std::tuple<int &&>, std::tuple<const unsigned int &, const std::allocator<int> &>>>);
ASSERT_EQ(std::get<0>(std::get<2>(args)), size);
}
TEST(UsesAllocatorConstructionArgs, PairNoArgs) {
[[maybe_unused]] const auto args = entt::uses_allocator_construction_args<std::pair<int, std::vector<int>>>(std::allocator<int>{});
static_assert(std::tuple_size_v<decltype(args)> == 3u);
static_assert(std::is_same_v<decltype(args), const std::tuple<std::piecewise_construct_t, std::tuple<>, std::tuple<const std::allocator<int> &>>>);
}
TEST(UsesAllocatorConstructionArgs, PairValues) {
const auto size = 42u;
const auto args = entt::uses_allocator_construction_args<std::pair<int, std::vector<int>>>(std::allocator<int>{}, 3, size);
static_assert(std::tuple_size_v<decltype(args)> == 3u);
static_assert(std::is_same_v<decltype(args), const std::tuple<std::piecewise_construct_t, std::tuple<int &&>, std::tuple<const unsigned int &, const std::allocator<int> &>>>);
ASSERT_EQ(std::get<0>(std::get<2>(args)), size);
}
TEST(UsesAllocatorConstructionArgs, PairConstLValueReference) {
const auto value = std::make_pair(3, 42u);
const auto args = entt::uses_allocator_construction_args<std::pair<int, std::vector<int>>>(std::allocator<int>{}, value);
static_assert(std::tuple_size_v<decltype(args)> == 3u);
static_assert(std::is_same_v<decltype(args), const std::tuple<std::piecewise_construct_t, std::tuple<const int &>, std::tuple<const unsigned int &, const std::allocator<int> &>>>);
ASSERT_EQ(std::get<0>(std::get<1>(args)), 3);
ASSERT_EQ(std::get<0>(std::get<2>(args)), 42u);
}
TEST(UsesAllocatorConstructionArgs, PairRValueReference) {
[[maybe_unused]] const auto args = entt::uses_allocator_construction_args<std::pair<int, std::vector<int>>>(std::allocator<int>{}, std::make_pair(3, 42u));
static_assert(std::tuple_size_v<decltype(args)> == 3u);
static_assert(std::is_same_v<decltype(args), const std::tuple<std::piecewise_construct_t, std::tuple<int &&>, std::tuple<unsigned int &&, const std::allocator<int> &>>>);
}
TEST(MakeObjUsingAllocator, Functionalities) {
const auto size = 42u;
test::throwing_allocator<int>::trigger_on_allocate = true;