vendor/llvm-project/llvmorg-16-init-18548-gb0daacf58f41

1 files changed, 221 insertions, 0 deletions

diff --git a/libcxx/include/__memory/uses_allocator_construction.h b/libcxx/include/__memory/uses_allocator_construction.h
new file mode 100644
index 000000000000..0f63b080daf3
--- /dev/null
+++ b/libcxx/include/__memory/uses_allocator_construction.h
@@ -0,0 +1,221 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___MEMORY_USES_ALLOCATOR_CONSTRUCTION_H
+#define _LIBCPP___MEMORY_USES_ALLOCATOR_CONSTRUCTION_H
+
+#include <__config>
+#include <__memory/construct_at.h>
+#include <__memory/uses_allocator.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/remove_cv.h>
+#include <__utility/declval.h>
+#include <__utility/pair.h>
+#include <tuple>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER >= 17
+
+template <class _Type>
+inline constexpr bool __is_std_pair = false;
+
+template <class _Type1, class _Type2>
+inline constexpr bool __is_std_pair<pair<_Type1, _Type2>> = true;
+
+template <class _Type, class _Alloc, class... _Args, __enable_if_t<!__is_std_pair<_Type>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+__uses_allocator_construction_args(const _Alloc& __alloc, _Args&&... __args) noexcept {
+  if constexpr (!uses_allocator_v<_Type, _Alloc> && is_constructible_v<_Type, _Args...>) {
+    return std::forward_as_tuple(std::forward<_Args>(__args)...);
+  } else if constexpr (uses_allocator_v<_Type, _Alloc> &&
+                       is_constructible_v<_Type, allocator_arg_t, const _Alloc&, _Args...>) {
+    return tuple<allocator_arg_t, const _Alloc&, _Args&&...>(allocator_arg, __alloc, std::forward<_Args>(__args)...);
+  } else if constexpr (uses_allocator_v<_Type, _Alloc> && is_constructible_v<_Type, _Args..., const _Alloc&>) {
+    return std::forward_as_tuple(std::forward<_Args>(__args)..., __alloc);
+  } else {
+    static_assert(
+        sizeof(_Type) + 1 == 0, "If uses_allocator_v<Type> is true, the type has to be allocator-constructible");
+  }
+}
+
+template <class _Pair, class _Alloc, class _Tuple1, class _Tuple2, __enable_if_t<__is_std_pair<_Pair>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto __uses_allocator_construction_args(
+    const _Alloc& __alloc, piecewise_construct_t, _Tuple1&& __x, _Tuple2&& __y) noexcept {
+  return std::make_tuple(
+      piecewise_construct,
+      std::apply(
+          [&__alloc](auto&&... __args1) {
+            return std::__uses_allocator_construction_args<typename _Pair::first_type>(
+                __alloc, std::forward<decltype(__args1)>(__args1)...);
+          },
+          std::forward<_Tuple1>(__x)),
+      std::apply(
+          [&__alloc](auto&&... __args2) {
+            return std::__uses_allocator_construction_args<typename _Pair::second_type>(
+                __alloc, std::forward<decltype(__args2)>(__args2)...);
+          },
+          std::forward<_Tuple2>(__y)));
+}
+
+template <class _Pair, class _Alloc, __enable_if_t<__is_std_pair<_Pair>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto __uses_allocator_construction_args(const _Alloc& __alloc) noexcept {
+  return std::__uses_allocator_construction_args<_Pair>(__alloc, piecewise_construct, tuple<>{}, tuple<>{});
+}
+
+template <class _Pair, class _Alloc, class _Up, class _Vp, __enable_if_t<__is_std_pair<_Pair>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+__uses_allocator_construction_args(const _Alloc& __alloc, _Up&& __u, _Vp&& __v) noexcept {
+  return std::__uses_allocator_construction_args<_Pair>(
+      __alloc,
+      piecewise_construct,
+      std::forward_as_tuple(std::forward<_Up>(__u)),
+      std::forward_as_tuple(std::forward<_Vp>(__v)));
+}
+
+#  if _LIBCPP_STD_VER > 20
+template <class _Pair, class _Alloc, class _Up, class _Vp, __enable_if_t<__is_std_pair<_Pair>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+__uses_allocator_construction_args(const _Alloc& __alloc, pair<_Up, _Vp>& __pair) noexcept {
+  return std::__uses_allocator_construction_args<_Pair>(
+      __alloc, piecewise_construct, std::forward_as_tuple(__pair.first), std::forward_as_tuple(__pair.second));
+}
+#  endif
+
+template <class _Pair, class _Alloc, class _Up, class _Vp, __enable_if_t<__is_std_pair<_Pair>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+__uses_allocator_construction_args(const _Alloc& __alloc, const pair<_Up, _Vp>& __pair) noexcept {
+  return std::__uses_allocator_construction_args<_Pair>(
+      __alloc, piecewise_construct, std::forward_as_tuple(__pair.first), std::forward_as_tuple(__pair.second));
+}
+
+template <class _Pair, class _Alloc, class _Up, class _Vp, __enable_if_t<__is_std_pair<_Pair>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+__uses_allocator_construction_args(const _Alloc& __alloc, pair<_Up, _Vp>&& __pair) noexcept {
+  return std::__uses_allocator_construction_args<_Pair>(
+      __alloc,
+      piecewise_construct,
+      std::forward_as_tuple(std::get<0>(std::move(__pair))),
+      std::forward_as_tuple(std::get<1>(std::move(__pair))));
+}
+
+#  if _LIBCPP_STD_VER > 20
+template <class _Pair, class _Alloc, class _Up, class _Vp, __enable_if_t<__is_std_pair<_Pair>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+__uses_allocator_construction_args(const _Alloc& __alloc, const pair<_Up, _Vp>&& __pair) noexcept {
+  return std::__uses_allocator_construction_args<_Pair>(
+      __alloc,
+      piecewise_construct,
+      std::forward_as_tuple(std::get<0>(std::move(__pair))),
+      std::forward_as_tuple(std::get<1>(std::move(__pair))));
+}
+#  endif
+
+namespace __uses_allocator_detail {
+
+template <class _Ap, class _Bp>
+void __fun(const pair<_Ap, _Bp>&);
+
+template <class _Tp>
+decltype(__uses_allocator_detail::__fun(std::declval<_Tp>()), true_type()) __convertible_to_const_pair_ref_impl(int);
+
+template <class>
+false_type __convertible_to_const_pair_ref_impl(...);
+
+template <class _Tp>
+inline constexpr bool __convertible_to_const_pair_ref =
+    decltype(__uses_allocator_detail::__convertible_to_const_pair_ref_impl<_Tp>(0))::value;
+
+} // namespace __uses_allocator_detail
+
+template <
+    class _Pair,
+    class _Alloc,
+    class _Type,
+    __enable_if_t<__is_std_pair<_Pair> && !__uses_allocator_detail::__convertible_to_const_pair_ref<_Type>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+__uses_allocator_construction_args(const _Alloc& __alloc, _Type&& __value) noexcept;
+
+template <class _Type, class _Alloc, class... _Args>
+_LIBCPP_HIDE_FROM_ABI constexpr _Type __make_obj_using_allocator(const _Alloc& __alloc, _Args&&... __args);
+
+template <class _Pair,
+          class _Alloc,
+          class _Type,
+          __enable_if_t<__is_std_pair<_Pair> && !__uses_allocator_detail::__convertible_to_const_pair_ref<_Type>, int>>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+__uses_allocator_construction_args(const _Alloc& __alloc, _Type&& __value) noexcept {
+  struct __pair_constructor {
+    using _PairMutable = remove_cv_t<_Pair>;
+
+    _LIBCPP_HIDE_FROM_ABI constexpr auto __do_construct(const _PairMutable& __pair) const {
+      return std::__make_obj_using_allocator<_PairMutable>(__alloc_, __pair);
+    }
+
+    _LIBCPP_HIDE_FROM_ABI constexpr auto __do_construct(_PairMutable&& __pair) const {
+      return std::__make_obj_using_allocator<_PairMutable>(__alloc_, std::move(__pair));
+    }
+
+    const _Alloc& __alloc_;
+    _Type& __value_;
+
+    _LIBCPP_HIDE_FROM_ABI constexpr operator _PairMutable() const {
+      return __do_construct(std::forward<_Type>(this->__value_));
+    }
+  };
+
+  return std::make_tuple(__pair_constructor{__alloc, __value});
+}
+
+template <class _Type, class _Alloc, class... _Args>
+_LIBCPP_HIDE_FROM_ABI constexpr _Type __make_obj_using_allocator(const _Alloc& __alloc, _Args&&... __args) {
+  return std::make_from_tuple<_Type>(
+      std::__uses_allocator_construction_args<_Type>(__alloc, std::forward<_Args>(__args)...));
+}
+
+template <class _Type, class _Alloc, class... _Args>
+_LIBCPP_HIDE_FROM_ABI constexpr _Type*
+__uninitialized_construct_using_allocator(_Type* __ptr, const _Alloc& __alloc, _Args&&... __args) {
+  return std::apply(
+      [&__ptr](auto&&... __xs) { return std::__construct_at(__ptr, std::forward<decltype(__xs)>(__xs)...); },
+      std::__uses_allocator_construction_args<_Type>(__alloc, std::forward<_Args>(__args)...));
+}
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#if _LIBCPP_STD_VER >= 20
+
+template <class _Type, class _Alloc, class... _Args>
+_LIBCPP_HIDE_FROM_ABI constexpr auto uses_allocator_construction_args(const _Alloc& __alloc, _Args&&... __args) noexcept
+    -> decltype(std::__uses_allocator_construction_args<_Type>(__alloc, std::forward<_Args>(__args)...)) {
+  return /*--*/ std::__uses_allocator_construction_args<_Type>(__alloc, std::forward<_Args>(__args)...);
+}
+
+template <class _Type, class _Alloc, class... _Args>
+_LIBCPP_HIDE_FROM_ABI constexpr auto make_obj_using_allocator(const _Alloc& __alloc, _Args&&... __args)
+    -> decltype(std::__make_obj_using_allocator<_Type>(__alloc, std::forward<_Args>(__args)...)) {
+  return /*--*/ std::__make_obj_using_allocator<_Type>(__alloc, std::forward<_Args>(__args)...);
+}
+
+template <class _Type, class _Alloc, class... _Args>
+_LIBCPP_HIDE_FROM_ABI constexpr auto
+uninitialized_construct_using_allocator(_Type* __ptr, const _Alloc& __alloc, _Args&&... __args)
+    -> decltype(std::__uninitialized_construct_using_allocator(__ptr, __alloc, std::forward<_Args>(__args)...)) {
+  return /*--*/ std::__uninitialized_construct_using_allocator(__ptr, __alloc, std::forward<_Args>(__args)...);
+}
+
+#endif // _LIBCPP_STD_VER >= 20
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___MEMORY_USES_ALLOCATOR_CONSTRUCTION_H