memory.h
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1 // Copyright 2017 The Abseil Authors.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // https://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 //
15 // -----------------------------------------------------------------------------
16 // File: memory.h
17 // -----------------------------------------------------------------------------
18 //
19 // This header file contains utility functions for managing the creation and
20 // conversion of smart pointers. This file is an extension to the C++
21 // standard <memory> library header file.
22 
23 #ifndef ABSL_MEMORY_MEMORY_H_
24 #define ABSL_MEMORY_MEMORY_H_
25 
26 #include <cstddef>
27 #include <limits>
28 #include <memory>
29 #include <new>
30 #include <type_traits>
31 #include <utility>
32 
33 #include "absl/base/macros.h"
34 #include "absl/meta/type_traits.h"
35 
36 namespace absl {
37 
38 // -----------------------------------------------------------------------------
39 // Function Template: WrapUnique()
40 // -----------------------------------------------------------------------------
41 //
42 // Adopts ownership from a raw pointer and transfers it to the returned
43 // `std::unique_ptr`, whose type is deduced. Because of this deduction, *do not*
44 // specify the template type `T` when calling `WrapUnique`.
45 //
46 // Example:
47 // X* NewX(int, int);
48 // auto x = WrapUnique(NewX(1, 2)); // 'x' is std::unique_ptr<X>.
49 //
50 // Do not call WrapUnique with an explicit type, as in
51 // `WrapUnique<X>(NewX(1, 2))`. The purpose of WrapUnique is to automatically
52 // deduce the pointer type. If you wish to make the type explicit, just use
53 // `std::unique_ptr` directly.
54 //
55 // auto x = std::unique_ptr<X>(NewX(1, 2));
56 // - or -
57 // std::unique_ptr<X> x(NewX(1, 2));
58 //
59 // While `absl::WrapUnique` is useful for capturing the output of a raw
60 // pointer factory, prefer 'absl::make_unique<T>(args...)' over
61 // 'absl::WrapUnique(new T(args...))'.
62 //
63 // auto x = WrapUnique(new X(1, 2)); // works, but nonideal.
64 // auto x = make_unique<X>(1, 2); // safer, standard, avoids raw 'new'.
65 //
66 // Note that `absl::WrapUnique(p)` is valid only if `delete p` is a valid
67 // expression. In particular, `absl::WrapUnique()` cannot wrap pointers to
68 // arrays, functions or void, and it must not be used to capture pointers
69 // obtained from array-new expressions (even though that would compile!).
70 template <typename T>
71 std::unique_ptr<T> WrapUnique(T* ptr) {
72  static_assert(!std::is_array<T>::value, "array types are unsupported");
73  static_assert(std::is_object<T>::value, "non-object types are unsupported");
74  return std::unique_ptr<T>(ptr);
75 }
76 
77 namespace memory_internal {
78 
79 // Traits to select proper overload and return type for `absl::make_unique<>`.
80 template <typename T>
82  using scalar = std::unique_ptr<T>;
83 };
84 template <typename T>
85 struct MakeUniqueResult<T[]> {
86  using array = std::unique_ptr<T[]>;
87 };
88 template <typename T, size_t N>
89 struct MakeUniqueResult<T[N]> {
90  using invalid = void;
91 };
92 
93 } // namespace memory_internal
94 
95 // gcc 4.8 has __cplusplus at 201301 but doesn't define make_unique. Other
96 // supported compilers either just define __cplusplus as 201103 but have
97 // make_unique (msvc), or have make_unique whenever __cplusplus > 201103 (clang)
98 #if (__cplusplus > 201103L || defined(_MSC_VER)) && \
99  !(defined(__GNUC__) && __GNUC__ == 4 && __GNUC_MINOR__ == 8)
100 using std::make_unique;
101 #else
102 // -----------------------------------------------------------------------------
103 // Function Template: make_unique<T>()
104 // -----------------------------------------------------------------------------
105 //
106 // Creates a `std::unique_ptr<>`, while avoiding issues creating temporaries
107 // during the construction process. `absl::make_unique<>` also avoids redundant
108 // type declarations, by avoiding the need to explicitly use the `new` operator.
109 //
110 // This implementation of `absl::make_unique<>` is designed for C++11 code and
111 // will be replaced in C++14 by the equivalent `std::make_unique<>` abstraction.
112 // `absl::make_unique<>` is designed to be 100% compatible with
113 // `std::make_unique<>` so that the eventual migration will involve a simple
114 // rename operation.
115 //
116 // For more background on why `std::unique_ptr<T>(new T(a,b))` is problematic,
117 // see Herb Sutter's explanation on
118 // (Exception-Safe Function Calls)[https://herbsutter.com/gotw/_102/].
119 // (In general, reviewers should treat `new T(a,b)` with scrutiny.)
120 //
121 // Example usage:
122 //
123 // auto p = make_unique<X>(args...); // 'p' is a std::unique_ptr<X>
124 // auto pa = make_unique<X[]>(5); // 'pa' is a std::unique_ptr<X[]>
125 //
126 // Three overloads of `absl::make_unique` are required:
127 //
128 // - For non-array T:
129 //
130 // Allocates a T with `new T(std::forward<Args> args...)`,
131 // forwarding all `args` to T's constructor.
132 // Returns a `std::unique_ptr<T>` owning that object.
133 //
134 // - For an array of unknown bounds T[]:
135 //
136 // `absl::make_unique<>` will allocate an array T of type U[] with
137 // `new U[n]()` and return a `std::unique_ptr<U[]>` owning that array.
138 //
139 // Note that 'U[n]()' is different from 'U[n]', and elements will be
140 // value-initialized. Note as well that `std::unique_ptr` will perform its
141 // own destruction of the array elements upon leaving scope, even though
142 // the array [] does not have a default destructor.
143 //
144 // NOTE: an array of unknown bounds T[] may still be (and often will be)
145 // initialized to have a size, and will still use this overload. E.g:
146 //
147 // auto my_array = absl::make_unique<int[]>(10);
148 //
149 // - For an array of known bounds T[N]:
150 //
151 // `absl::make_unique<>` is deleted (like with `std::make_unique<>`) as
152 // this overload is not useful.
153 //
154 // NOTE: an array of known bounds T[N] is not considered a useful
155 // construction, and may cause undefined behavior in templates. E.g:
156 //
157 // auto my_array = absl::make_unique<int[10]>();
158 //
159 // In those cases, of course, you can still use the overload above and
160 // simply initialize it to its desired size:
161 //
162 // auto my_array = absl::make_unique<int[]>(10);
163 
164 // `absl::make_unique` overload for non-array types.
165 template <typename T, typename... Args>
167  Args&&... args) {
168  return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
169 }
170 
171 // `absl::make_unique` overload for an array T[] of unknown bounds.
172 // The array allocation needs to use the `new T[size]` form and cannot take
173 // element constructor arguments. The `std::unique_ptr` will manage destructing
174 // these array elements.
175 template <typename T>
177  return std::unique_ptr<T>(new typename absl::remove_extent_t<T>[n]());
178 }
179 
180 // `absl::make_unique` overload for an array T[N] of known bounds.
181 // This construction will be rejected.
182 template <typename T, typename... Args>
184  Args&&... /* args */) = delete;
185 #endif
186 
187 // -----------------------------------------------------------------------------
188 // Function Template: RawPtr()
189 // -----------------------------------------------------------------------------
190 //
191 // Extracts the raw pointer from a pointer-like value `ptr`. `absl::RawPtr` is
192 // useful within templates that need to handle a complement of raw pointers,
193 // `std::nullptr_t`, and smart pointers.
194 template <typename T>
195 auto RawPtr(T&& ptr) -> decltype(std::addressof(*ptr)) {
196  // ptr is a forwarding reference to support Ts with non-const operators.
197  return (ptr != nullptr) ? std::addressof(*ptr) : nullptr;
198 }
199 inline std::nullptr_t RawPtr(std::nullptr_t) { return nullptr; }
200 
201 // -----------------------------------------------------------------------------
202 // Function Template: ShareUniquePtr()
203 // -----------------------------------------------------------------------------
204 //
205 // Adopts a `std::unique_ptr` rvalue and returns a `std::shared_ptr` of deduced
206 // type. Ownership (if any) of the held value is transferred to the returned
207 // shared pointer.
208 //
209 // Example:
210 //
211 // auto up = absl::make_unique<int>(10);
212 // auto sp = absl::ShareUniquePtr(std::move(up)); // shared_ptr<int>
213 // CHECK_EQ(*sp, 10);
214 // CHECK(up == nullptr);
215 //
216 // Note that this conversion is correct even when T is an array type, and more
217 // generally it works for *any* deleter of the `unique_ptr` (single-object
218 // deleter, array deleter, or any custom deleter), since the deleter is adopted
219 // by the shared pointer as well. The deleter is copied (unless it is a
220 // reference).
221 //
222 // Implements the resolution of [LWG 2415](http://wg21.link/lwg2415), by which a
223 // null shared pointer does not attempt to call the deleter.
224 template <typename T, typename D>
225 std::shared_ptr<T> ShareUniquePtr(std::unique_ptr<T, D>&& ptr) {
226  return ptr ? std::shared_ptr<T>(std::move(ptr)) : std::shared_ptr<T>();
227 }
228 
229 // -----------------------------------------------------------------------------
230 // Function Template: WeakenPtr()
231 // -----------------------------------------------------------------------------
232 //
233 // Creates a weak pointer associated with a given shared pointer. The returned
234 // value is a `std::weak_ptr` of deduced type.
235 //
236 // Example:
237 //
238 // auto sp = std::make_shared<int>(10);
239 // auto wp = absl::WeakenPtr(sp);
240 // CHECK_EQ(sp.get(), wp.lock().get());
241 // sp.reset();
242 // CHECK(wp.lock() == nullptr);
243 //
244 template <typename T>
245 std::weak_ptr<T> WeakenPtr(const std::shared_ptr<T>& ptr) {
246  return std::weak_ptr<T>(ptr);
247 }
248 
249 namespace memory_internal {
250 
251 // ExtractOr<E, O, D>::type evaluates to E<O> if possible. Otherwise, D.
252 template <template <typename> class Extract, typename Obj, typename Default,
253  typename>
254 struct ExtractOr {
255  using type = Default;
256 };
257 
258 template <template <typename> class Extract, typename Obj, typename Default>
259 struct ExtractOr<Extract, Obj, Default, void_t<Extract<Obj>>> {
260  using type = Extract<Obj>;
261 };
262 
263 template <template <typename> class Extract, typename Obj, typename Default>
265 
266 // Extractors for the features of allocators.
267 template <typename T>
268 using GetPointer = typename T::pointer;
269 
270 template <typename T>
271 using GetConstPointer = typename T::const_pointer;
272 
273 template <typename T>
274 using GetVoidPointer = typename T::void_pointer;
275 
276 template <typename T>
277 using GetConstVoidPointer = typename T::const_void_pointer;
278 
279 template <typename T>
280 using GetDifferenceType = typename T::difference_type;
281 
282 template <typename T>
283 using GetSizeType = typename T::size_type;
284 
285 template <typename T>
287  typename T::propagate_on_container_copy_assignment;
288 
289 template <typename T>
291  typename T::propagate_on_container_move_assignment;
292 
293 template <typename T>
294 using GetPropagateOnContainerSwap = typename T::propagate_on_container_swap;
295 
296 template <typename T>
297 using GetIsAlwaysEqual = typename T::is_always_equal;
298 
299 template <typename T>
300 struct GetFirstArg;
301 
302 template <template <typename...> class Class, typename T, typename... Args>
303 struct GetFirstArg<Class<T, Args...>> {
304  using type = T;
305 };
306 
307 template <typename Ptr, typename = void>
308 struct ElementType {
309  using type = typename GetFirstArg<Ptr>::type;
310 };
311 
312 template <typename T>
313 struct ElementType<T, void_t<typename T::element_type>> {
314  using type = typename T::element_type;
315 };
316 
317 template <typename T, typename U>
319 
320 template <template <typename...> class Class, typename T, typename... Args,
321  typename U>
322 struct RebindFirstArg<Class<T, Args...>, U> {
323  using type = Class<U, Args...>;
324 };
325 
326 template <typename T, typename U, typename = void>
327 struct RebindPtr {
329 };
330 
331 template <typename T, typename U>
332 struct RebindPtr<T, U, void_t<typename T::template rebind<U>>> {
333  using type = typename T::template rebind<U>;
334 };
335 
336 template <typename T, typename U>
337 constexpr bool HasRebindAlloc(...) {
338  return false;
339 }
340 
341 template <typename T, typename U>
342 constexpr bool HasRebindAlloc(typename T::template rebind<U>::other*) {
343  return true;
344 }
345 
346 template <typename T, typename U, bool = HasRebindAlloc<T, U>(nullptr)>
347 struct RebindAlloc {
349 };
350 
351 template <typename T, typename U>
352 struct RebindAlloc<T, U, true> {
353  using type = typename T::template rebind<U>::other;
354 };
355 
356 } // namespace memory_internal
357 
358 // -----------------------------------------------------------------------------
359 // Class Template: pointer_traits
360 // -----------------------------------------------------------------------------
361 //
362 // An implementation of C++11's std::pointer_traits.
363 //
364 // Provided for portability on toolchains that have a working C++11 compiler,
365 // but the standard library is lacking in C++11 support. For example, some
366 // version of the Android NDK.
367 //
368 
369 template <typename Ptr>
371  using pointer = Ptr;
372 
373  // element_type:
374  // Ptr::element_type if present. Otherwise T if Ptr is a template
375  // instantiation Template<T, Args...>
377 
378  // difference_type:
379  // Ptr::difference_type if present, otherwise std::ptrdiff_t
380  using difference_type =
382  std::ptrdiff_t>;
383 
384  // rebind:
385  // Ptr::rebind<U> if exists, otherwise Template<U, Args...> if Ptr is a
386  // template instantiation Template<T, Args...>
387  template <typename U>
389 
390  // pointer_to:
391  // Calls Ptr::pointer_to(r)
392  static pointer pointer_to(element_type& r) { // NOLINT(runtime/references)
393  return Ptr::pointer_to(r);
394  }
395 };
396 
397 // Specialization for T*.
398 template <typename T>
399 struct pointer_traits<T*> {
400  using pointer = T*;
401  using element_type = T;
402  using difference_type = std::ptrdiff_t;
403 
404  template <typename U>
405  using rebind = U*;
406 
407  // pointer_to:
408  // Calls std::addressof(r)
410  element_type& r) noexcept { // NOLINT(runtime/references)
411  return std::addressof(r);
412  }
413 };
414 
415 // -----------------------------------------------------------------------------
416 // Class Template: allocator_traits
417 // -----------------------------------------------------------------------------
418 //
419 // A C++11 compatible implementation of C++17's std::allocator_traits.
420 //
421 template <typename Alloc>
423  using allocator_type = Alloc;
424 
425  // value_type:
426  // Alloc::value_type
427  using value_type = typename Alloc::value_type;
428 
429  // pointer:
430  // Alloc::pointer if present, otherwise value_type*
432  Alloc, value_type*>;
433 
434  // const_pointer:
435  // Alloc::const_pointer if present, otherwise
436  // absl::pointer_traits<pointer>::rebind<const value_type>
437  using const_pointer =
440  template rebind<const value_type>>;
441 
442  // void_pointer:
443  // Alloc::void_pointer if present, otherwise
444  // absl::pointer_traits<pointer>::rebind<void>
448 
449  // const_void_pointer:
450  // Alloc::const_void_pointer if present, otherwise
451  // absl::pointer_traits<pointer>::rebind<const void>
454  typename absl::pointer_traits<pointer>::template rebind<const void>>;
455 
456  // difference_type:
457  // Alloc::difference_type if present, otherwise
458  // absl::pointer_traits<pointer>::difference_type
462 
463  // size_type:
464  // Alloc::size_type if present, otherwise
465  // std::make_unsigned<difference_type>::type
468  typename std::make_unsigned<difference_type>::type>;
469 
470  // propagate_on_container_copy_assignment:
471  // Alloc::propagate_on_container_copy_assignment if present, otherwise
472  // std::false_type
475  std::false_type>;
476 
477  // propagate_on_container_move_assignment:
478  // Alloc::propagate_on_container_move_assignment if present, otherwise
479  // std::false_type
482  std::false_type>;
483 
484  // propagate_on_container_swap:
485  // Alloc::propagate_on_container_swap if present, otherwise std::false_type
488  Alloc, std::false_type>;
489 
490  // is_always_equal:
491  // Alloc::is_always_equal if present, otherwise std::is_empty<Alloc>::type
492  using is_always_equal =
494  typename std::is_empty<Alloc>::type>;
495 
496  // rebind_alloc:
497  // Alloc::rebind<T>::other if present, otherwise Alloc<T, Args> if this Alloc
498  // is Alloc<U, Args>
499  template <typename T>
501 
502  // rebind_traits:
503  // absl::allocator_traits<rebind_alloc<T>>
504  template <typename T>
506 
507  // allocate(Alloc& a, size_type n):
508  // Calls a.allocate(n)
509  static pointer allocate(Alloc& a, // NOLINT(runtime/references)
510  size_type n) {
511  return a.allocate(n);
512  }
513 
514  // allocate(Alloc& a, size_type n, const_void_pointer hint):
515  // Calls a.allocate(n, hint) if possible.
516  // If not possible, calls a.allocate(n)
517  static pointer allocate(Alloc& a, size_type n, // NOLINT(runtime/references)
518  const_void_pointer hint) {
519  return allocate_impl(0, a, n, hint);
520  }
521 
522  // deallocate(Alloc& a, pointer p, size_type n):
523  // Calls a.deallocate(p, n)
524  static void deallocate(Alloc& a, pointer p, // NOLINT(runtime/references)
525  size_type n) {
526  a.deallocate(p, n);
527  }
528 
529  // construct(Alloc& a, T* p, Args&&... args):
530  // Calls a.construct(p, std::forward<Args>(args)...) if possible.
531  // If not possible, calls
532  // ::new (static_cast<void*>(p)) T(std::forward<Args>(args)...)
533  template <typename T, typename... Args>
534  static void construct(Alloc& a, T* p, // NOLINT(runtime/references)
535  Args&&... args) {
536  construct_impl(0, a, p, std::forward<Args>(args)...);
537  }
538 
539  // destroy(Alloc& a, T* p):
540  // Calls a.destroy(p) if possible. If not possible, calls p->~T().
541  template <typename T>
542  static void destroy(Alloc& a, T* p) { // NOLINT(runtime/references)
543  destroy_impl(0, a, p);
544  }
545 
546  // max_size(const Alloc& a):
547  // Returns a.max_size() if possible. If not possible, returns
548  // std::numeric_limits<size_type>::max() / sizeof(value_type)
549  static size_type max_size(const Alloc& a) { return max_size_impl(0, a); }
550 
551  // select_on_container_copy_construction(const Alloc& a):
552  // Returns a.select_on_container_copy_construction() if possible.
553  // If not possible, returns a.
554  static Alloc select_on_container_copy_construction(const Alloc& a) {
555  return select_on_container_copy_construction_impl(0, a);
556  }
557 
558  private:
559  template <typename A>
560  static auto allocate_impl(int, A& a, // NOLINT(runtime/references)
562  -> decltype(a.allocate(n, hint)) {
563  return a.allocate(n, hint);
564  }
565  static pointer allocate_impl(char, Alloc& a, // NOLINT(runtime/references)
567  return a.allocate(n);
568  }
569 
570  template <typename A, typename... Args>
571  static auto construct_impl(int, A& a, // NOLINT(runtime/references)
572  Args&&... args)
573  -> decltype(a.construct(std::forward<Args>(args)...)) {
574  a.construct(std::forward<Args>(args)...);
575  }
576 
577  template <typename T, typename... Args>
578  static void construct_impl(char, Alloc&, T* p, Args&&... args) {
579  ::new (static_cast<void*>(p)) T(std::forward<Args>(args)...);
580  }
581 
582  template <typename A, typename T>
583  static auto destroy_impl(int, A& a, // NOLINT(runtime/references)
584  T* p) -> decltype(a.destroy(p)) {
585  a.destroy(p);
586  }
587  template <typename T>
588  static void destroy_impl(char, Alloc&, T* p) {
589  p->~T();
590  }
591 
592  template <typename A>
593  static auto max_size_impl(int, const A& a) -> decltype(a.max_size()) {
594  return a.max_size();
595  }
596  static size_type max_size_impl(char, const Alloc&) {
597  return (std::numeric_limits<size_type>::max)() / sizeof(value_type);
598  }
599 
600  template <typename A>
602  -> decltype(a.select_on_container_copy_construction()) {
603  return a.select_on_container_copy_construction();
604  }
606  const Alloc& a) {
607  return a;
608  }
609 };
610 
611 namespace memory_internal {
612 
613 // This template alias transforms Alloc::is_nothrow into a metafunction with
614 // Alloc as a parameter so it can be used with ExtractOrT<>.
615 template <typename Alloc>
616 using GetIsNothrow = typename Alloc::is_nothrow;
617 
618 } // namespace memory_internal
619 
620 // ABSL_ALLOCATOR_NOTHROW is a build time configuration macro for user to
621 // specify whether the default allocation function can throw or never throws.
622 // If the allocation function never throws, user should define it to a non-zero
623 // value (e.g. via `-DABSL_ALLOCATOR_NOTHROW`).
624 // If the allocation function can throw, user should leave it undefined or
625 // define it to zero.
626 //
627 // allocator_is_nothrow<Alloc> is a traits class that derives from
628 // Alloc::is_nothrow if present, otherwise std::false_type. It's specialized
629 // for Alloc = std::allocator<T> for any type T according to the state of
630 // ABSL_ALLOCATOR_NOTHROW.
631 //
632 // default_allocator_is_nothrow is a class that derives from std::true_type
633 // when the default allocator (global operator new) never throws, and
634 // std::false_type when it can throw. It is a convenience shorthand for writing
635 // allocator_is_nothrow<std::allocator<T>> (T can be any type).
636 // NOTE: allocator_is_nothrow<std::allocator<T>> is guaranteed to derive from
637 // the same type for all T, because users should specialize neither
638 // allocator_is_nothrow nor std::allocator.
639 template <typename Alloc>
641  : memory_internal::ExtractOrT<memory_internal::GetIsNothrow, Alloc,
642  std::false_type> {};
643 
644 #if defined(ABSL_ALLOCATOR_NOTHROW) && ABSL_ALLOCATOR_NOTHROW
645 template <typename T>
646 struct allocator_is_nothrow<std::allocator<T>> : std::true_type {};
647 struct default_allocator_is_nothrow : std::true_type {};
648 #else
649 struct default_allocator_is_nothrow : std::false_type {};
650 #endif
651 
652 namespace memory_internal {
653 template <typename Allocator, typename Iterator, typename... Args>
654 void ConstructRange(Allocator& alloc, Iterator first, Iterator last,
655  const Args&... args) {
656  for (Iterator cur = first; cur != last; ++cur) {
658  std::allocator_traits<Allocator>::construct(alloc, std::addressof(*cur),
659  args...);
660  }
662  while (cur != first) {
663  --cur;
664  std::allocator_traits<Allocator>::destroy(alloc, std::addressof(*cur));
665  }
667  }
668  }
669 }
670 
671 template <typename Allocator, typename Iterator, typename InputIterator>
672 void CopyRange(Allocator& alloc, Iterator destination, InputIterator first,
673  InputIterator last) {
674  for (Iterator cur = destination; first != last;
675  static_cast<void>(++cur), static_cast<void>(++first)) {
677  std::allocator_traits<Allocator>::construct(alloc, std::addressof(*cur),
678  *first);
679  }
681  while (cur != destination) {
682  --cur;
683  std::allocator_traits<Allocator>::destroy(alloc, std::addressof(*cur));
684  }
686  }
687  }
688 }
689 } // namespace memory_internal
690 } // namespace absl
691 
692 #endif // ABSL_MEMORY_MEMORY_H_
memory_internal::ExtractOrT< memory_internal::GetIsAlwaysEqual, Alloc, typename std::is_empty< Alloc >::type > is_always_equal
Definition: memory.h:494
static pointer pointer_to(element_type &r)
Definition: memory.h:392
memory_internal::ExtractOrT< memory_internal::GetVoidPointer, Alloc, typename absl::pointer_traits< pointer >::template rebind< void >> void_pointer
Definition: memory.h:447
static auto construct_impl(int, A &a, Args &&...args) -> decltype(a.construct(std::forward< Args >(args)...))
Definition: memory.h:571
static Alloc select_on_container_copy_construction_impl(char, const Alloc &a)
Definition: memory.h:605
typename RebindFirstArg< T, U >::type type
Definition: memory.h:328
typename RebindFirstArg< T, U >::type type
Definition: memory.h:348
static void deallocate(Alloc &a, pointer p, size_type n)
Definition: memory.h:524
static pointer allocate(Alloc &a, size_type n, const_void_pointer hint)
Definition: memory.h:517
std::unique_ptr< T > scalar
Definition: memory.h:82
typename Alloc::is_nothrow GetIsNothrow
Definition: memory.h:616
typename memory_internal::RebindAlloc< Alloc, T >::type rebind_alloc
Definition: memory.h:500
typename T::propagate_on_container_move_assignment GetPropagateOnContainerMoveAssignment
Definition: memory.h:291
std::unique_ptr< T > WrapUnique(T *ptr)
Definition: memory.h:71
typename T::void_pointer GetVoidPointer
Definition: memory.h:274
typename std::remove_extent< T >::type remove_extent_t
Definition: type_traits.h:534
memory_internal::ExtractOrT< memory_internal::GetDifferenceType, Alloc, typename absl::pointer_traits< pointer >::difference_type > difference_type
Definition: memory.h:461
static void destroy(Alloc &a, T *p)
Definition: memory.h:542
static auto destroy_impl(int, A &a, T *p) -> decltype(a.destroy(p))
Definition: memory.h:583
static pointer allocate(Alloc &a, size_type n)
Definition: memory.h:509
typename GetFirstArg< Ptr >::type type
Definition: memory.h:309
static void construct_impl(char, Alloc &, T *p, Args &&...args)
Definition: memory.h:578
typename T::is_always_equal GetIsAlwaysEqual
Definition: memory.h:297
typename T::size_type GetSizeType
Definition: memory.h:283
memory_internal::ExtractOrT< memory_internal::GetPropagateOnContainerMoveAssignment, Alloc, std::false_type > propagate_on_container_move_assignment
Definition: memory.h:482
std::shared_ptr< T > ShareUniquePtr(std::unique_ptr< T, D > &&ptr)
Definition: memory.h:225
#define ABSL_INTERNAL_CATCH_ANY
Definition: macros.h:209
memory_internal::ExtractOrT< memory_internal::GetSizeType, Alloc, typename std::make_unsigned< difference_type >::type > size_type
Definition: memory.h:468
Definition: algorithm.h:29
typename T::const_pointer GetConstPointer
Definition: memory.h:271
typename memory_internal::ElementType< Ptr >::type element_type
Definition: memory.h:376
static size_type max_size(const Alloc &a)
Definition: memory.h:549
static std::function< void(void *, Slot *)> destroy
typename ExtractOr< Extract, Obj, Default, void >::type ExtractOrT
Definition: memory.h:264
static auto max_size_impl(int, const A &a) -> decltype(a.max_size())
Definition: memory.h:593
char * ptr
size_t value
void CopyRange(Allocator &alloc, Iterator destination, InputIterator first, InputIterator last)
Definition: memory.h:672
static auto select_on_container_copy_construction_impl(int, const A &a) -> decltype(a.select_on_container_copy_construction())
Definition: memory.h:601
memory_internal::ExtractOrT< memory_internal::GetPointer, Alloc, value_type * > pointer
Definition: memory.h:432
auto RawPtr(T &&ptr) -> decltype(std::addressof(*ptr))
Definition: memory.h:195
static auto allocate_impl(int, A &a, size_type n, const_void_pointer hint) -> decltype(a.allocate(n, hint))
Definition: memory.h:560
static std::function< void(void *, Slot *, Slot)> construct
typename Alloc::value_type value_type
Definition: memory.h:427
void ConstructRange(Allocator &alloc, Iterator first, Iterator last, const Args &...args)
Definition: memory.h:654
static size_type max_size_impl(char, const Alloc &)
Definition: memory.h:596
typename type_traits_internal::VoidTImpl< Ts... >::type void_t
Definition: type_traits.h:171
memory_internal::ExtractOrT< memory_internal::GetConstPointer, Alloc, typename absl::pointer_traits< pointer >::template rebind< const value_type >> const_pointer
Definition: memory.h:440
typename T::difference_type GetDifferenceType
Definition: memory.h:280
static pointer allocate_impl(char, Alloc &a, size_type n, const_void_pointer)
Definition: memory.h:565
typename T::template rebind< U >::other type
Definition: memory.h:353
static Alloc select_on_container_copy_construction(const Alloc &a)
Definition: memory.h:554
memory_internal::MakeUniqueResult< T >::invalid make_unique(Args &&...)=delete
typename T::propagate_on_container_copy_assignment GetPropagateOnContainerCopyAssignment
Definition: memory.h:287
memory_internal::ExtractOrT< memory_internal::GetPropagateOnContainerSwap, Alloc, std::false_type > propagate_on_container_swap
Definition: memory.h:488
#define ABSL_INTERNAL_TRY
Definition: macros.h:208
std::weak_ptr< T > WeakenPtr(const std::shared_ptr< T > &ptr)
Definition: memory.h:245
static pointer pointer_to(element_type &r) noexcept
Definition: memory.h:409
memory_internal::MakeUniqueResult< T >::scalar make_unique(Args &&...args)
Definition: memory.h:166
#define ABSL_INTERNAL_RETHROW
Definition: macros.h:210
std::allocator< int > alloc
constexpr absl::remove_reference_t< T > && move(T &&t) noexcept
Definition: utility.h:219
typename memory_internal::RebindPtr< Ptr, U >::type rebind
Definition: memory.h:388
typename T::propagate_on_container_swap GetPropagateOnContainerSwap
Definition: memory.h:294
memory_internal::ExtractOrT< memory_internal::GetDifferenceType, Ptr, std::ptrdiff_t > difference_type
Definition: memory.h:382
memory_internal::ExtractOrT< memory_internal::GetConstVoidPointer, Alloc, typename absl::pointer_traits< pointer >::template rebind< const void >> const_void_pointer
Definition: memory.h:454
constexpr bool HasRebindAlloc(...)
Definition: memory.h:337
typename T::const_void_pointer GetConstVoidPointer
Definition: memory.h:277
static void construct(Alloc &a, T *p, Args &&...args)
Definition: memory.h:534
typename T::pointer GetPointer
Definition: memory.h:268
static void destroy_impl(char, Alloc &, T *p)
Definition: memory.h:588
memory_internal::ExtractOrT< memory_internal::GetPropagateOnContainerCopyAssignment, Alloc, std::false_type > propagate_on_container_copy_assignment
Definition: memory.h:475
std::ptrdiff_t difference_type
Definition: memory.h:402


abseil_cpp
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autogenerated on Wed Jun 19 2019 19:19:57