1// -*- C++ -*- 2//===----------------------------------------------------------------------===// 3// 4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5// See https://llvm.org/LICENSE.txt for license information. 6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7// 8//===----------------------------------------------------------------------===// 9 10#ifndef _LIBCPP___MEMORY_ALLOCATOR_TRAITS_H 11#define _LIBCPP___MEMORY_ALLOCATOR_TRAITS_H 12 13#include <__config> 14#include <__memory/construct_at.h> 15#include <__memory/pointer_traits.h> 16#include <__type_traits/enable_if.h> 17#include <__type_traits/is_copy_constructible.h> 18#include <__type_traits/is_empty.h> 19#include <__type_traits/is_move_constructible.h> 20#include <__type_traits/make_unsigned.h> 21#include <__type_traits/remove_reference.h> 22#include <__type_traits/void_t.h> 23#include <__utility/declval.h> 24#include <__utility/forward.h> 25#include <limits> 26 27#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 28# pragma GCC system_header 29#endif 30 31_LIBCPP_PUSH_MACROS 32#include <__undef_macros> 33 34_LIBCPP_BEGIN_NAMESPACE_STD 35 36#define _LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(NAME, PROPERTY) \ 37 template <class _Tp, class = void> struct NAME : false_type { }; \ 38 template <class _Tp> struct NAME<_Tp, __void_t<typename _Tp:: PROPERTY > > : true_type { } 39 40// __pointer 41_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_pointer, pointer); 42template <class _Tp, class _Alloc, 43 class _RawAlloc = __libcpp_remove_reference_t<_Alloc>, 44 bool = __has_pointer<_RawAlloc>::value> 45struct __pointer { 46 using type _LIBCPP_NODEBUG = typename _RawAlloc::pointer; 47}; 48template <class _Tp, class _Alloc, class _RawAlloc> 49struct __pointer<_Tp, _Alloc, _RawAlloc, false> { 50 using type _LIBCPP_NODEBUG = _Tp*; 51}; 52 53// __const_pointer 54_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_const_pointer, const_pointer); 55template <class _Tp, class _Ptr, class _Alloc, 56 bool = __has_const_pointer<_Alloc>::value> 57struct __const_pointer { 58 using type _LIBCPP_NODEBUG = typename _Alloc::const_pointer; 59}; 60template <class _Tp, class _Ptr, class _Alloc> 61struct __const_pointer<_Tp, _Ptr, _Alloc, false> { 62#ifdef _LIBCPP_CXX03_LANG 63 using type = typename pointer_traits<_Ptr>::template rebind<const _Tp>::other; 64#else 65 using type _LIBCPP_NODEBUG = typename pointer_traits<_Ptr>::template rebind<const _Tp>; 66#endif 67}; 68 69// __void_pointer 70_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_void_pointer, void_pointer); 71template <class _Ptr, class _Alloc, 72 bool = __has_void_pointer<_Alloc>::value> 73struct __void_pointer { 74 using type _LIBCPP_NODEBUG = typename _Alloc::void_pointer; 75}; 76template <class _Ptr, class _Alloc> 77struct __void_pointer<_Ptr, _Alloc, false> { 78#ifdef _LIBCPP_CXX03_LANG 79 using type _LIBCPP_NODEBUG = typename pointer_traits<_Ptr>::template rebind<void>::other; 80#else 81 using type _LIBCPP_NODEBUG = typename pointer_traits<_Ptr>::template rebind<void>; 82#endif 83}; 84 85// __const_void_pointer 86_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_const_void_pointer, const_void_pointer); 87template <class _Ptr, class _Alloc, 88 bool = __has_const_void_pointer<_Alloc>::value> 89struct __const_void_pointer { 90 using type _LIBCPP_NODEBUG = typename _Alloc::const_void_pointer; 91}; 92template <class _Ptr, class _Alloc> 93struct __const_void_pointer<_Ptr, _Alloc, false> { 94#ifdef _LIBCPP_CXX03_LANG 95 using type _LIBCPP_NODEBUG = typename pointer_traits<_Ptr>::template rebind<const void>::other; 96#else 97 using type _LIBCPP_NODEBUG = typename pointer_traits<_Ptr>::template rebind<const void>; 98#endif 99}; 100 101// __size_type 102_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_size_type, size_type); 103template <class _Alloc, class _DiffType, bool = __has_size_type<_Alloc>::value> 104struct __size_type : make_unsigned<_DiffType> { }; 105template <class _Alloc, class _DiffType> 106struct __size_type<_Alloc, _DiffType, true> { 107 using type _LIBCPP_NODEBUG = typename _Alloc::size_type; 108}; 109 110// __alloc_traits_difference_type 111_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_alloc_traits_difference_type, difference_type); 112template <class _Alloc, class _Ptr, bool = __has_alloc_traits_difference_type<_Alloc>::value> 113struct __alloc_traits_difference_type { 114 using type _LIBCPP_NODEBUG = typename pointer_traits<_Ptr>::difference_type; 115}; 116template <class _Alloc, class _Ptr> 117struct __alloc_traits_difference_type<_Alloc, _Ptr, true> { 118 using type _LIBCPP_NODEBUG = typename _Alloc::difference_type; 119}; 120 121// __propagate_on_container_copy_assignment 122_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_propagate_on_container_copy_assignment, propagate_on_container_copy_assignment); 123template <class _Alloc, bool = __has_propagate_on_container_copy_assignment<_Alloc>::value> 124struct __propagate_on_container_copy_assignment : false_type { }; 125template <class _Alloc> 126struct __propagate_on_container_copy_assignment<_Alloc, true> { 127 using type _LIBCPP_NODEBUG = typename _Alloc::propagate_on_container_copy_assignment; 128}; 129 130// __propagate_on_container_move_assignment 131_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_propagate_on_container_move_assignment, propagate_on_container_move_assignment); 132template <class _Alloc, bool = __has_propagate_on_container_move_assignment<_Alloc>::value> 133struct __propagate_on_container_move_assignment : false_type { }; 134template <class _Alloc> 135struct __propagate_on_container_move_assignment<_Alloc, true> { 136 using type _LIBCPP_NODEBUG = typename _Alloc::propagate_on_container_move_assignment; 137}; 138 139// __propagate_on_container_swap 140_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_propagate_on_container_swap, propagate_on_container_swap); 141template <class _Alloc, bool = __has_propagate_on_container_swap<_Alloc>::value> 142struct __propagate_on_container_swap : false_type { }; 143template <class _Alloc> 144struct __propagate_on_container_swap<_Alloc, true> { 145 using type _LIBCPP_NODEBUG = typename _Alloc::propagate_on_container_swap; 146}; 147 148// __is_always_equal 149_LIBCPP_ALLOCATOR_TRAITS_HAS_XXX(__has_is_always_equal, is_always_equal); 150template <class _Alloc, bool = __has_is_always_equal<_Alloc>::value> 151struct __is_always_equal : is_empty<_Alloc> { }; 152template <class _Alloc> 153struct __is_always_equal<_Alloc, true> { 154 using type _LIBCPP_NODEBUG = typename _Alloc::is_always_equal; 155}; 156 157// __allocator_traits_rebind 158_LIBCPP_SUPPRESS_DEPRECATED_PUSH 159template <class _Tp, class _Up, class = void> 160struct __has_rebind_other : false_type { }; 161template <class _Tp, class _Up> 162struct __has_rebind_other<_Tp, _Up, __void_t<typename _Tp::template rebind<_Up>::other> > : true_type { }; 163 164template <class _Tp, class _Up, bool = __has_rebind_other<_Tp, _Up>::value> 165struct __allocator_traits_rebind { 166 static_assert(__has_rebind_other<_Tp, _Up>::value, "This allocator has to implement rebind"); 167 using type _LIBCPP_NODEBUG = typename _Tp::template rebind<_Up>::other; 168}; 169template <template <class, class...> class _Alloc, class _Tp, class ..._Args, class _Up> 170struct __allocator_traits_rebind<_Alloc<_Tp, _Args...>, _Up, true> { 171 using type _LIBCPP_NODEBUG = typename _Alloc<_Tp, _Args...>::template rebind<_Up>::other; 172}; 173template <template <class, class...> class _Alloc, class _Tp, class ..._Args, class _Up> 174struct __allocator_traits_rebind<_Alloc<_Tp, _Args...>, _Up, false> { 175 using type _LIBCPP_NODEBUG = _Alloc<_Up, _Args...>; 176}; 177_LIBCPP_SUPPRESS_DEPRECATED_POP 178 179template<class _Alloc, class _Tp> 180using __allocator_traits_rebind_t = typename __allocator_traits_rebind<_Alloc, _Tp>::type; 181 182_LIBCPP_SUPPRESS_DEPRECATED_PUSH 183 184// __has_allocate_hint 185template <class _Alloc, class _SizeType, class _ConstVoidPtr, class = void> 186struct __has_allocate_hint : false_type { }; 187 188template <class _Alloc, class _SizeType, class _ConstVoidPtr> 189struct __has_allocate_hint<_Alloc, _SizeType, _ConstVoidPtr, decltype( 190 (void)std::declval<_Alloc>().allocate(std::declval<_SizeType>(), std::declval<_ConstVoidPtr>()) 191)> : true_type { }; 192 193// __has_construct 194template <class, class _Alloc, class ..._Args> 195struct __has_construct_impl : false_type { }; 196 197template <class _Alloc, class ..._Args> 198struct __has_construct_impl<decltype( 199 (void)std::declval<_Alloc>().construct(std::declval<_Args>()...) 200), _Alloc, _Args...> : true_type { }; 201 202template <class _Alloc, class ..._Args> 203struct __has_construct : __has_construct_impl<void, _Alloc, _Args...> { }; 204 205// __has_destroy 206template <class _Alloc, class _Pointer, class = void> 207struct __has_destroy : false_type { }; 208 209template <class _Alloc, class _Pointer> 210struct __has_destroy<_Alloc, _Pointer, decltype( 211 (void)std::declval<_Alloc>().destroy(std::declval<_Pointer>()) 212)> : true_type { }; 213 214// __has_max_size 215template <class _Alloc, class = void> 216struct __has_max_size : false_type { }; 217 218template <class _Alloc> 219struct __has_max_size<_Alloc, decltype( 220 (void)std::declval<_Alloc&>().max_size() 221)> : true_type { }; 222 223// __has_select_on_container_copy_construction 224template <class _Alloc, class = void> 225struct __has_select_on_container_copy_construction : false_type { }; 226 227template <class _Alloc> 228struct __has_select_on_container_copy_construction<_Alloc, decltype( 229 (void)std::declval<_Alloc>().select_on_container_copy_construction() 230)> : true_type { }; 231 232_LIBCPP_SUPPRESS_DEPRECATED_POP 233 234template <class _Alloc> 235struct _LIBCPP_TEMPLATE_VIS allocator_traits 236{ 237 using allocator_type = _Alloc; 238 using value_type = typename allocator_type::value_type; 239 using pointer = typename __pointer<value_type, allocator_type>::type; 240 using const_pointer = typename __const_pointer<value_type, pointer, allocator_type>::type; 241 using void_pointer = typename __void_pointer<pointer, allocator_type>::type; 242 using const_void_pointer = typename __const_void_pointer<pointer, allocator_type>::type; 243 using difference_type = typename __alloc_traits_difference_type<allocator_type, pointer>::type; 244 using size_type = typename __size_type<allocator_type, difference_type>::type; 245 using propagate_on_container_copy_assignment = typename __propagate_on_container_copy_assignment<allocator_type>::type; 246 using propagate_on_container_move_assignment = typename __propagate_on_container_move_assignment<allocator_type>::type; 247 using propagate_on_container_swap = typename __propagate_on_container_swap<allocator_type>::type; 248 using is_always_equal = typename __is_always_equal<allocator_type>::type; 249 250#ifndef _LIBCPP_CXX03_LANG 251 template <class _Tp> 252 using rebind_alloc = __allocator_traits_rebind_t<allocator_type, _Tp>; 253 template <class _Tp> 254 using rebind_traits = allocator_traits<rebind_alloc<_Tp> >; 255#else // _LIBCPP_CXX03_LANG 256 template <class _Tp> 257 struct rebind_alloc { 258 using other = __allocator_traits_rebind_t<allocator_type, _Tp>; 259 }; 260 template <class _Tp> 261 struct rebind_traits { 262 using other = allocator_traits<typename rebind_alloc<_Tp>::other>; 263 }; 264#endif // _LIBCPP_CXX03_LANG 265 266 _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 267 static pointer allocate(allocator_type& __a, size_type __n) { 268 return __a.allocate(__n); 269 } 270 271 template <class _Ap = _Alloc, class = 272 __enable_if_t<__has_allocate_hint<_Ap, size_type, const_void_pointer>::value> > 273 _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 274 static pointer allocate(allocator_type& __a, size_type __n, const_void_pointer __hint) { 275 _LIBCPP_SUPPRESS_DEPRECATED_PUSH 276 return __a.allocate(__n, __hint); 277 _LIBCPP_SUPPRESS_DEPRECATED_POP 278 } 279 template <class _Ap = _Alloc, class = void, class = 280 __enable_if_t<!__has_allocate_hint<_Ap, size_type, const_void_pointer>::value> > 281 _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 282 static pointer allocate(allocator_type& __a, size_type __n, const_void_pointer) { 283 return __a.allocate(__n); 284 } 285 286 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 287 static void deallocate(allocator_type& __a, pointer __p, size_type __n) _NOEXCEPT { 288 __a.deallocate(__p, __n); 289 } 290 291 template <class _Tp, class... _Args, class = 292 __enable_if_t<__has_construct<allocator_type, _Tp*, _Args...>::value> > 293 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 294 static void construct(allocator_type& __a, _Tp* __p, _Args&&... __args) { 295 _LIBCPP_SUPPRESS_DEPRECATED_PUSH 296 __a.construct(__p, _VSTD::forward<_Args>(__args)...); 297 _LIBCPP_SUPPRESS_DEPRECATED_POP 298 } 299 template <class _Tp, class... _Args, class = void, class = 300 __enable_if_t<!__has_construct<allocator_type, _Tp*, _Args...>::value> > 301 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 302 static void construct(allocator_type&, _Tp* __p, _Args&&... __args) { 303#if _LIBCPP_STD_VER > 17 304 _VSTD::construct_at(__p, _VSTD::forward<_Args>(__args)...); 305#else 306 ::new ((void*)__p) _Tp(_VSTD::forward<_Args>(__args)...); 307#endif 308 } 309 310 template <class _Tp, class = 311 __enable_if_t<__has_destroy<allocator_type, _Tp*>::value> > 312 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 313 static void destroy(allocator_type& __a, _Tp* __p) { 314 _LIBCPP_SUPPRESS_DEPRECATED_PUSH 315 __a.destroy(__p); 316 _LIBCPP_SUPPRESS_DEPRECATED_POP 317 } 318 template <class _Tp, class = void, class = 319 __enable_if_t<!__has_destroy<allocator_type, _Tp*>::value> > 320 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 321 static void destroy(allocator_type&, _Tp* __p) { 322#if _LIBCPP_STD_VER > 17 323 _VSTD::destroy_at(__p); 324#else 325 __p->~_Tp(); 326#endif 327 } 328 329 template <class _Ap = _Alloc, class = 330 __enable_if_t<__has_max_size<const _Ap>::value> > 331 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 332 static size_type max_size(const allocator_type& __a) _NOEXCEPT { 333 _LIBCPP_SUPPRESS_DEPRECATED_PUSH 334 return __a.max_size(); 335 _LIBCPP_SUPPRESS_DEPRECATED_POP 336 } 337 template <class _Ap = _Alloc, class = void, class = 338 __enable_if_t<!__has_max_size<const _Ap>::value> > 339 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 340 static size_type max_size(const allocator_type&) _NOEXCEPT { 341 return numeric_limits<size_type>::max() / sizeof(value_type); 342 } 343 344 template <class _Ap = _Alloc, class = 345 __enable_if_t<__has_select_on_container_copy_construction<const _Ap>::value> > 346 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 347 static allocator_type select_on_container_copy_construction(const allocator_type& __a) { 348 return __a.select_on_container_copy_construction(); 349 } 350 template <class _Ap = _Alloc, class = void, class = 351 __enable_if_t<!__has_select_on_container_copy_construction<const _Ap>::value> > 352 _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX20 353 static allocator_type select_on_container_copy_construction(const allocator_type& __a) { 354 return __a; 355 } 356}; 357 358#ifndef _LIBCPP_CXX03_LANG 359template <class _Traits, class _Tp> 360using __rebind_alloc _LIBCPP_NODEBUG = typename _Traits::template rebind_alloc<_Tp>; 361#else 362template <class _Traits, class _Tp> 363using __rebind_alloc = typename _Traits::template rebind_alloc<_Tp>::other; 364#endif 365 366// __is_default_allocator 367template <class _Tp> 368struct __is_default_allocator : false_type { }; 369 370template <class> class allocator; 371 372template <class _Tp> 373struct __is_default_allocator<allocator<_Tp> > : true_type { }; 374 375// __is_cpp17_move_insertable 376template <class _Alloc, class = void> 377struct __is_cpp17_move_insertable 378 : is_move_constructible<typename _Alloc::value_type> 379{ }; 380 381template <class _Alloc> 382struct __is_cpp17_move_insertable<_Alloc, __enable_if_t< 383 !__is_default_allocator<_Alloc>::value && 384 __has_construct<_Alloc, typename _Alloc::value_type*, typename _Alloc::value_type&&>::value 385> > : true_type { }; 386 387// __is_cpp17_copy_insertable 388template <class _Alloc, class = void> 389struct __is_cpp17_copy_insertable 390 : integral_constant<bool, 391 is_copy_constructible<typename _Alloc::value_type>::value && 392 __is_cpp17_move_insertable<_Alloc>::value 393 > 394{ }; 395 396template <class _Alloc> 397struct __is_cpp17_copy_insertable<_Alloc, __enable_if_t< 398 !__is_default_allocator<_Alloc>::value && 399 __has_construct<_Alloc, typename _Alloc::value_type*, const typename _Alloc::value_type&>::value 400> > 401 : __is_cpp17_move_insertable<_Alloc> 402{ }; 403 404#undef _LIBCPP_ALLOCATOR_TRAITS_HAS_XXX 405 406_LIBCPP_END_NAMESPACE_STD 407 408_LIBCPP_POP_MACROS 409 410#endif // _LIBCPP___MEMORY_ALLOCATOR_TRAITS_H 411