xref: /freebsd/contrib/llvm-project/libcxx/include/new (revision 1db9f3b21e39176dd5b67cf8ac378633b172463e)
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_NEW
11#define _LIBCPP_NEW
12
13/*
14    new synopsis
15
16namespace std
17{
18
19class bad_alloc
20    : public exception
21{
22public:
23    bad_alloc() noexcept;
24    bad_alloc(const bad_alloc&) noexcept;
25    bad_alloc& operator=(const bad_alloc&) noexcept;
26    virtual const char* what() const noexcept;
27};
28
29class bad_array_new_length : public bad_alloc // C++14
30{
31public:
32    bad_array_new_length() noexcept;
33};
34
35enum class align_val_t : size_t {}; // C++17
36
37struct destroying_delete_t { // C++20
38  explicit destroying_delete_t() = default;
39};
40inline constexpr destroying_delete_t destroying_delete{}; // C++20
41
42struct nothrow_t { explicit nothrow_t() = default; };
43extern const nothrow_t nothrow;
44typedef void (*new_handler)();
45new_handler set_new_handler(new_handler new_p) noexcept;
46new_handler get_new_handler() noexcept;
47
48// 21.6.4, pointer optimization barrier
49template <class T> [[nodiscard]] constexpr T* launder(T* p) noexcept;   // C++17, nodiscard since C++20
50}  // std
51
52void* operator new(std::size_t size);                                   // replaceable, nodiscard in C++20
53void* operator new(std::size_t size, std::align_val_t alignment);       // replaceable, C++17, nodiscard in C++20
54void* operator new(std::size_t size, const std::nothrow_t&) noexcept;   // replaceable, nodiscard in C++20
55void* operator new(std::size_t size, std::align_val_t alignment,
56                   const std::nothrow_t&) noexcept;                     // replaceable, C++17, nodiscard in C++20
57void  operator delete(void* ptr) noexcept;                              // replaceable
58void  operator delete(void* ptr, std::size_t size) noexcept;            // replaceable, C++14
59void  operator delete(void* ptr, std::align_val_t alignment) noexcept;  // replaceable, C++17
60void  operator delete(void* ptr, std::size_t size,
61                      std::align_val_t alignment) noexcept;             // replaceable, C++17
62void  operator delete(void* ptr, const std::nothrow_t&) noexcept;       // replaceable
63void  operator delete(void* ptr, std:align_val_t alignment,
64                      const std::nothrow_t&) noexcept;                  // replaceable, C++17
65
66void* operator new[](std::size_t size);                                 // replaceable, nodiscard in C++20
67void* operator new[](std::size_t size,
68                     std::align_val_t alignment) noexcept;              // replaceable, C++17, nodiscard in C++20
69void* operator new[](std::size_t size, const std::nothrow_t&) noexcept; // replaceable, nodiscard in C++20
70void* operator new[](std::size_t size, std::align_val_t alignment,
71                     const std::nothrow_t&) noexcept;                   // replaceable, C++17, nodiscard in C++20
72void  operator delete[](void* ptr) noexcept;                            // replaceable
73void  operator delete[](void* ptr, std::size_t size) noexcept;          // replaceable, C++14
74void  operator delete[](void* ptr,
75                        std::align_val_t alignment) noexcept;           // replaceable, C++17
76void  operator delete[](void* ptr, std::size_t size,
77                        std::align_val_t alignment) noexcept;           // replaceable, C++17
78void  operator delete[](void* ptr, const std::nothrow_t&) noexcept;     // replaceable
79void  operator delete[](void* ptr, std::align_val_t alignment,
80                        const std::nothrow_t&) noexcept;                // replaceable, C++17
81
82void* operator new  (std::size_t size, void* ptr) noexcept;             // nodiscard in C++20
83void* operator new[](std::size_t size, void* ptr) noexcept;             // nodiscard in C++20
84void  operator delete  (void* ptr, void*) noexcept;
85void  operator delete[](void* ptr, void*) noexcept;
86
87*/
88
89#include <__assert> // all public C++ headers provide the assertion handler
90#include <__availability>
91#include <__config>
92#include <__exception/exception.h>
93#include <__type_traits/is_function.h>
94#include <__type_traits/is_same.h>
95#include <__type_traits/remove_cv.h>
96#include <cstddef>
97#include <version>
98
99#if defined(_LIBCPP_ABI_VCRUNTIME)
100#  include <new.h>
101#endif
102
103#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
104#  pragma GCC system_header
105#endif
106
107#if !defined(__cpp_sized_deallocation) || __cpp_sized_deallocation < 201309L
108#  define _LIBCPP_HAS_NO_LANGUAGE_SIZED_DEALLOCATION
109#endif
110
111#if !defined(_LIBCPP_BUILDING_LIBRARY) && _LIBCPP_STD_VER < 14 && defined(_LIBCPP_HAS_NO_LANGUAGE_SIZED_DEALLOCATION)
112#  define _LIBCPP_HAS_NO_LIBRARY_SIZED_DEALLOCATION
113#endif
114
115#if defined(_LIBCPP_HAS_NO_LIBRARY_SIZED_DEALLOCATION) || defined(_LIBCPP_HAS_NO_LANGUAGE_SIZED_DEALLOCATION)
116#  define _LIBCPP_HAS_NO_SIZED_DEALLOCATION
117#endif
118
119namespace std // purposefully not using versioning namespace
120{
121
122#if !defined(_LIBCPP_ABI_VCRUNTIME)
123struct _LIBCPP_EXPORTED_FROM_ABI nothrow_t {
124  explicit nothrow_t() = default;
125};
126extern _LIBCPP_EXPORTED_FROM_ABI const nothrow_t nothrow;
127
128class _LIBCPP_EXPORTED_FROM_ABI bad_alloc : public exception {
129public:
130  bad_alloc() _NOEXCEPT;
131  _LIBCPP_HIDE_FROM_ABI bad_alloc(const bad_alloc&) _NOEXCEPT            = default;
132  _LIBCPP_HIDE_FROM_ABI bad_alloc& operator=(const bad_alloc&) _NOEXCEPT = default;
133  ~bad_alloc() _NOEXCEPT override;
134  const char* what() const _NOEXCEPT override;
135};
136
137class _LIBCPP_EXPORTED_FROM_ABI bad_array_new_length : public bad_alloc {
138public:
139  bad_array_new_length() _NOEXCEPT;
140  _LIBCPP_HIDE_FROM_ABI bad_array_new_length(const bad_array_new_length&) _NOEXCEPT            = default;
141  _LIBCPP_HIDE_FROM_ABI bad_array_new_length& operator=(const bad_array_new_length&) _NOEXCEPT = default;
142  ~bad_array_new_length() _NOEXCEPT override;
143  const char* what() const _NOEXCEPT override;
144};
145
146typedef void (*new_handler)();
147_LIBCPP_EXPORTED_FROM_ABI new_handler set_new_handler(new_handler) _NOEXCEPT;
148_LIBCPP_EXPORTED_FROM_ABI new_handler get_new_handler() _NOEXCEPT;
149
150#elif defined(_HAS_EXCEPTIONS) && _HAS_EXCEPTIONS == 0 // !_LIBCPP_ABI_VCRUNTIME
151
152// When _HAS_EXCEPTIONS == 0, these complete definitions are needed,
153// since they would normally be provided in vcruntime_exception.h
154class bad_alloc : public exception {
155public:
156  bad_alloc() noexcept : exception("bad allocation") {}
157
158private:
159  friend class bad_array_new_length;
160
161  bad_alloc(char const* const __message) noexcept : exception(__message) {}
162};
163
164class bad_array_new_length : public bad_alloc {
165public:
166  bad_array_new_length() noexcept : bad_alloc("bad array new length") {}
167};
168#endif // defined(_LIBCPP_ABI_VCRUNTIME) && defined(_HAS_EXCEPTIONS) && _HAS_EXCEPTIONS == 0
169
170_LIBCPP_NORETURN _LIBCPP_EXPORTED_FROM_ABI void __throw_bad_alloc(); // not in C++ spec
171
172_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void __throw_bad_array_new_length() {
173#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
174  throw bad_array_new_length();
175#else
176  _LIBCPP_VERBOSE_ABORT("bad_array_new_length was thrown in -fno-exceptions mode");
177#endif
178}
179
180#if !defined(_LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION) && !defined(_LIBCPP_ABI_VCRUNTIME)
181#  ifndef _LIBCPP_CXX03_LANG
182enum class align_val_t : size_t {};
183#  else
184enum align_val_t { __zero = 0, __max = (size_t)-1 };
185#  endif
186#endif
187
188#if _LIBCPP_STD_VER >= 20
189// Enable the declaration even if the compiler doesn't support the language
190// feature.
191struct destroying_delete_t {
192  explicit destroying_delete_t() = default;
193};
194inline constexpr destroying_delete_t destroying_delete{};
195#endif // _LIBCPP_STD_VER >= 20
196
197} // namespace std
198
199#if defined(_LIBCPP_CXX03_LANG)
200#  define _THROW_BAD_ALLOC throw(std::bad_alloc)
201#else
202#  define _THROW_BAD_ALLOC
203#endif
204
205#if !defined(_LIBCPP_ABI_VCRUNTIME)
206
207_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new(std::size_t __sz) _THROW_BAD_ALLOC;
208_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_OVERRIDABLE_FUNC_VIS void*
209operator new(std::size_t __sz, const std::nothrow_t&) _NOEXCEPT _LIBCPP_NOALIAS;
210_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete(void* __p) _NOEXCEPT;
211_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete(void* __p, const std::nothrow_t&) _NOEXCEPT;
212#  ifndef _LIBCPP_HAS_NO_LIBRARY_SIZED_DEALLOCATION
213_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete(void* __p, std::size_t __sz) _NOEXCEPT;
214#  endif
215
216_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new[](std::size_t __sz) _THROW_BAD_ALLOC;
217_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_OVERRIDABLE_FUNC_VIS void*
218operator new[](std::size_t __sz, const std::nothrow_t&) _NOEXCEPT _LIBCPP_NOALIAS;
219_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete[](void* __p) _NOEXCEPT;
220_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete[](void* __p, const std::nothrow_t&) _NOEXCEPT;
221#  ifndef _LIBCPP_HAS_NO_LIBRARY_SIZED_DEALLOCATION
222_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete[](void* __p, std::size_t __sz) _NOEXCEPT;
223#  endif
224
225#  ifndef _LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION
226_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_OVERRIDABLE_FUNC_VIS void*
227operator new(std::size_t __sz, std::align_val_t) _THROW_BAD_ALLOC;
228_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_OVERRIDABLE_FUNC_VIS void*
229operator new(std::size_t __sz, std::align_val_t, const std::nothrow_t&) _NOEXCEPT _LIBCPP_NOALIAS;
230_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete(void* __p, std::align_val_t) _NOEXCEPT;
231_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete(void* __p, std::align_val_t, const std::nothrow_t&) _NOEXCEPT;
232#    ifndef _LIBCPP_HAS_NO_LIBRARY_SIZED_DEALLOCATION
233_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete(void* __p, std::size_t __sz, std::align_val_t) _NOEXCEPT;
234#    endif
235
236_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_OVERRIDABLE_FUNC_VIS void*
237operator new[](std::size_t __sz, std::align_val_t) _THROW_BAD_ALLOC;
238_LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_OVERRIDABLE_FUNC_VIS void*
239operator new[](std::size_t __sz, std::align_val_t, const std::nothrow_t&) _NOEXCEPT _LIBCPP_NOALIAS;
240_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete[](void* __p, std::align_val_t) _NOEXCEPT;
241_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete[](void* __p, std::align_val_t, const std::nothrow_t&) _NOEXCEPT;
242#    ifndef _LIBCPP_HAS_NO_LIBRARY_SIZED_DEALLOCATION
243_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete[](void* __p, std::size_t __sz, std::align_val_t) _NOEXCEPT;
244#    endif
245#  endif
246
247_LIBCPP_NODISCARD_AFTER_CXX17 inline _LIBCPP_HIDE_FROM_ABI void* operator new(std::size_t, void* __p) _NOEXCEPT {
248  return __p;
249}
250_LIBCPP_NODISCARD_AFTER_CXX17 inline _LIBCPP_HIDE_FROM_ABI void* operator new[](std::size_t, void* __p) _NOEXCEPT {
251  return __p;
252}
253inline _LIBCPP_HIDE_FROM_ABI void operator delete(void*, void*) _NOEXCEPT {}
254inline _LIBCPP_HIDE_FROM_ABI void operator delete[](void*, void*) _NOEXCEPT {}
255
256#endif // !_LIBCPP_ABI_VCRUNTIME
257
258_LIBCPP_BEGIN_NAMESPACE_STD
259
260_LIBCPP_CONSTEXPR inline _LIBCPP_HIDE_FROM_ABI bool __is_overaligned_for_new(size_t __align) _NOEXCEPT {
261#ifdef __STDCPP_DEFAULT_NEW_ALIGNMENT__
262  return __align > __STDCPP_DEFAULT_NEW_ALIGNMENT__;
263#else
264  return __align > _LIBCPP_ALIGNOF(max_align_t);
265#endif
266}
267
268template <class... _Args>
269_LIBCPP_HIDE_FROM_ABI void* __libcpp_operator_new(_Args... __args) {
270#if __has_builtin(__builtin_operator_new) && __has_builtin(__builtin_operator_delete)
271  return __builtin_operator_new(__args...);
272#else
273  return ::operator new(__args...);
274#endif
275}
276
277template <class... _Args>
278_LIBCPP_HIDE_FROM_ABI void __libcpp_operator_delete(_Args... __args) {
279#if __has_builtin(__builtin_operator_new) && __has_builtin(__builtin_operator_delete)
280  __builtin_operator_delete(__args...);
281#else
282  ::operator delete(__args...);
283#endif
284}
285
286inline _LIBCPP_HIDE_FROM_ABI void* __libcpp_allocate(size_t __size, size_t __align) {
287#ifndef _LIBCPP_HAS_NO_ALIGNED_ALLOCATION
288  if (__is_overaligned_for_new(__align)) {
289    const align_val_t __align_val = static_cast<align_val_t>(__align);
290    return __libcpp_operator_new(__size, __align_val);
291  }
292#endif
293
294  (void)__align;
295  return __libcpp_operator_new(__size);
296}
297
298template <class... _Args>
299_LIBCPP_HIDE_FROM_ABI void __do_deallocate_handle_size(void* __ptr, size_t __size, _Args... __args) {
300#ifdef _LIBCPP_HAS_NO_SIZED_DEALLOCATION
301  (void)__size;
302  return std::__libcpp_operator_delete(__ptr, __args...);
303#else
304  return std::__libcpp_operator_delete(__ptr, __size, __args...);
305#endif
306}
307
308inline _LIBCPP_HIDE_FROM_ABI void __libcpp_deallocate(void* __ptr, size_t __size, size_t __align) {
309#if defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION)
310  (void)__align;
311  return __do_deallocate_handle_size(__ptr, __size);
312#else
313  if (__is_overaligned_for_new(__align)) {
314    const align_val_t __align_val = static_cast<align_val_t>(__align);
315    return __do_deallocate_handle_size(__ptr, __size, __align_val);
316  } else {
317    return __do_deallocate_handle_size(__ptr, __size);
318  }
319#endif
320}
321
322inline _LIBCPP_HIDE_FROM_ABI void __libcpp_deallocate_unsized(void* __ptr, size_t __align) {
323#if defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION)
324  (void)__align;
325  return __libcpp_operator_delete(__ptr);
326#else
327  if (__is_overaligned_for_new(__align)) {
328    const align_val_t __align_val = static_cast<align_val_t>(__align);
329    return __libcpp_operator_delete(__ptr, __align_val);
330  } else {
331    return __libcpp_operator_delete(__ptr);
332  }
333#endif
334}
335
336template <class _Tp>
337_LIBCPP_NODISCARD_AFTER_CXX17 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Tp* __launder(_Tp* __p) _NOEXCEPT {
338  static_assert(!(is_function<_Tp>::value), "can't launder functions");
339  static_assert(!(is_same<void, __remove_cv_t<_Tp> >::value), "can't launder cv-void");
340  return __builtin_launder(__p);
341}
342
343#if _LIBCPP_STD_VER >= 17
344template <class _Tp>
345_LIBCPP_NODISCARD_AFTER_CXX17 inline _LIBCPP_HIDE_FROM_ABI constexpr _Tp* launder(_Tp* __p) noexcept {
346  return std::__launder(__p);
347}
348#endif
349
350#if _LIBCPP_STD_VER >= 17
351
352#  if defined(__GCC_DESTRUCTIVE_SIZE) && defined(__GCC_CONSTRUCTIVE_SIZE)
353
354inline constexpr size_t hardware_destructive_interference_size  = __GCC_DESTRUCTIVE_SIZE;
355inline constexpr size_t hardware_constructive_interference_size = __GCC_CONSTRUCTIVE_SIZE;
356
357#  endif // defined(__GCC_DESTRUCTIVE_SIZE) && defined(__GCC_CONSTRUCTIVE_SIZE)
358
359#endif // _LIBCPP_STD_VER >= 17
360
361_LIBCPP_END_NAMESPACE_STD
362
363#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
364#  include <cstdlib>
365#  include <exception>
366#  include <type_traits>
367#endif
368
369#endif // _LIBCPP_NEW
370