xref: /freebsd/contrib/llvm-project/libcxx/include/new (revision b64c5a0ace59af62eff52bfe110a521dc73c937b)
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 <__config>
90#include <__exception/exception.h>
91#include <__type_traits/is_function.h>
92#include <__type_traits/is_same.h>
93#include <__type_traits/remove_cv.h>
94#include <__verbose_abort>
95#include <cstddef>
96#include <version>
97
98#if defined(_LIBCPP_ABI_VCRUNTIME)
99#  include <new.h>
100#endif
101
102#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
103#  pragma GCC system_header
104#endif
105
106#if !defined(__cpp_sized_deallocation) || __cpp_sized_deallocation < 201309L
107#  define _LIBCPP_HAS_NO_LANGUAGE_SIZED_DEALLOCATION
108#endif
109
110#if !defined(_LIBCPP_BUILDING_LIBRARY) && _LIBCPP_STD_VER < 14 && defined(_LIBCPP_HAS_NO_LANGUAGE_SIZED_DEALLOCATION)
111#  define _LIBCPP_HAS_NO_LIBRARY_SIZED_DEALLOCATION
112#endif
113
114#if defined(_LIBCPP_HAS_NO_LIBRARY_SIZED_DEALLOCATION) || defined(_LIBCPP_HAS_NO_LANGUAGE_SIZED_DEALLOCATION)
115#  define _LIBCPP_HAS_NO_SIZED_DEALLOCATION
116#endif
117
118namespace std // purposefully not using versioning namespace
119{
120
121#if !defined(_LIBCPP_ABI_VCRUNTIME)
122struct _LIBCPP_EXPORTED_FROM_ABI nothrow_t {
123  explicit nothrow_t() = default;
124};
125extern _LIBCPP_EXPORTED_FROM_ABI const nothrow_t nothrow;
126
127class _LIBCPP_EXPORTED_FROM_ABI bad_alloc : public exception {
128public:
129  bad_alloc() _NOEXCEPT;
130  _LIBCPP_HIDE_FROM_ABI bad_alloc(const bad_alloc&) _NOEXCEPT            = default;
131  _LIBCPP_HIDE_FROM_ABI bad_alloc& operator=(const bad_alloc&) _NOEXCEPT = default;
132  ~bad_alloc() _NOEXCEPT override;
133  const char* what() const _NOEXCEPT override;
134};
135
136class _LIBCPP_EXPORTED_FROM_ABI bad_array_new_length : public bad_alloc {
137public:
138  bad_array_new_length() _NOEXCEPT;
139  _LIBCPP_HIDE_FROM_ABI bad_array_new_length(const bad_array_new_length&) _NOEXCEPT            = default;
140  _LIBCPP_HIDE_FROM_ABI bad_array_new_length& operator=(const bad_array_new_length&) _NOEXCEPT = default;
141  ~bad_array_new_length() _NOEXCEPT override;
142  const char* what() const _NOEXCEPT override;
143};
144
145typedef void (*new_handler)();
146_LIBCPP_EXPORTED_FROM_ABI new_handler set_new_handler(new_handler) _NOEXCEPT;
147_LIBCPP_EXPORTED_FROM_ABI new_handler get_new_handler() _NOEXCEPT;
148
149#elif defined(_HAS_EXCEPTIONS) && _HAS_EXCEPTIONS == 0 // !_LIBCPP_ABI_VCRUNTIME
150
151// When _HAS_EXCEPTIONS == 0, these complete definitions are needed,
152// since they would normally be provided in vcruntime_exception.h
153class bad_alloc : public exception {
154public:
155  bad_alloc() noexcept : exception("bad allocation") {}
156
157private:
158  friend class bad_array_new_length;
159
160  bad_alloc(char const* const __message) noexcept : exception(__message) {}
161};
162
163class bad_array_new_length : public bad_alloc {
164public:
165  bad_array_new_length() noexcept : bad_alloc("bad array new length") {}
166};
167#endif // defined(_LIBCPP_ABI_VCRUNTIME) && defined(_HAS_EXCEPTIONS) && _HAS_EXCEPTIONS == 0
168
169_LIBCPP_NORETURN _LIBCPP_EXPORTED_FROM_ABI void __throw_bad_alloc(); // not in C++ spec
170
171_LIBCPP_NORETURN inline _LIBCPP_HIDE_FROM_ABI void __throw_bad_array_new_length() {
172#ifndef _LIBCPP_HAS_NO_EXCEPTIONS
173  throw bad_array_new_length();
174#else
175  _LIBCPP_VERBOSE_ABORT("bad_array_new_length was thrown in -fno-exceptions mode");
176#endif
177}
178
179#if !defined(_LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION) && !defined(_LIBCPP_ABI_VCRUNTIME)
180#  ifndef _LIBCPP_CXX03_LANG
181enum class align_val_t : size_t {};
182#  else
183enum align_val_t { __zero = 0, __max = (size_t)-1 };
184#  endif
185#endif
186
187#if _LIBCPP_STD_VER >= 20
188// Enable the declaration even if the compiler doesn't support the language
189// feature.
190struct destroying_delete_t {
191  explicit destroying_delete_t() = default;
192};
193inline constexpr destroying_delete_t destroying_delete{};
194#endif // _LIBCPP_STD_VER >= 20
195
196} // namespace std
197
198#if defined(_LIBCPP_CXX03_LANG)
199#  define _THROW_BAD_ALLOC throw(std::bad_alloc)
200#else
201#  define _THROW_BAD_ALLOC
202#endif
203
204#if !defined(_LIBCPP_ABI_VCRUNTIME)
205
206_LIBCPP_NODISCARD _LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new(std::size_t __sz) _THROW_BAD_ALLOC;
207_LIBCPP_NODISCARD _LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new(std::size_t __sz, const std::nothrow_t&) _NOEXCEPT
208    _LIBCPP_NOALIAS;
209_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete(void* __p) _NOEXCEPT;
210_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete(void* __p, const std::nothrow_t&) _NOEXCEPT;
211#  ifndef _LIBCPP_HAS_NO_LIBRARY_SIZED_DEALLOCATION
212_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete(void* __p, std::size_t __sz) _NOEXCEPT;
213#  endif
214
215_LIBCPP_NODISCARD _LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new[](std::size_t __sz) _THROW_BAD_ALLOC;
216_LIBCPP_NODISCARD _LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new[](std::size_t __sz, const std::nothrow_t&) _NOEXCEPT
217    _LIBCPP_NOALIAS;
218_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete[](void* __p) _NOEXCEPT;
219_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete[](void* __p, const std::nothrow_t&) _NOEXCEPT;
220#  ifndef _LIBCPP_HAS_NO_LIBRARY_SIZED_DEALLOCATION
221_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete[](void* __p, std::size_t __sz) _NOEXCEPT;
222#  endif
223
224#  ifndef _LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION
225_LIBCPP_NODISCARD _LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new(std::size_t __sz, std::align_val_t) _THROW_BAD_ALLOC;
226_LIBCPP_NODISCARD _LIBCPP_OVERRIDABLE_FUNC_VIS void*
227operator new(std::size_t __sz, std::align_val_t, const std::nothrow_t&) _NOEXCEPT _LIBCPP_NOALIAS;
228_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete(void* __p, std::align_val_t) _NOEXCEPT;
229_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete(void* __p, std::align_val_t, const std::nothrow_t&) _NOEXCEPT;
230#    ifndef _LIBCPP_HAS_NO_LIBRARY_SIZED_DEALLOCATION
231_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete(void* __p, std::size_t __sz, std::align_val_t) _NOEXCEPT;
232#    endif
233
234_LIBCPP_NODISCARD _LIBCPP_OVERRIDABLE_FUNC_VIS void*
235operator new[](std::size_t __sz, std::align_val_t) _THROW_BAD_ALLOC;
236_LIBCPP_NODISCARD _LIBCPP_OVERRIDABLE_FUNC_VIS void*
237operator new[](std::size_t __sz, std::align_val_t, const std::nothrow_t&) _NOEXCEPT _LIBCPP_NOALIAS;
238_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete[](void* __p, std::align_val_t) _NOEXCEPT;
239_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete[](void* __p, std::align_val_t, const std::nothrow_t&) _NOEXCEPT;
240#    ifndef _LIBCPP_HAS_NO_LIBRARY_SIZED_DEALLOCATION
241_LIBCPP_OVERRIDABLE_FUNC_VIS void operator delete[](void* __p, std::size_t __sz, std::align_val_t) _NOEXCEPT;
242#    endif
243#  endif
244
245_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI void* operator new(std::size_t, void* __p) _NOEXCEPT { return __p; }
246_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI void* operator new[](std::size_t, void* __p) _NOEXCEPT { return __p; }
247inline _LIBCPP_HIDE_FROM_ABI void operator delete(void*, void*) _NOEXCEPT {}
248inline _LIBCPP_HIDE_FROM_ABI void operator delete[](void*, void*) _NOEXCEPT {}
249
250#endif // !_LIBCPP_ABI_VCRUNTIME
251
252_LIBCPP_BEGIN_NAMESPACE_STD
253
254_LIBCPP_CONSTEXPR inline _LIBCPP_HIDE_FROM_ABI bool __is_overaligned_for_new(size_t __align) _NOEXCEPT {
255#ifdef __STDCPP_DEFAULT_NEW_ALIGNMENT__
256  return __align > __STDCPP_DEFAULT_NEW_ALIGNMENT__;
257#else
258  return __align > _LIBCPP_ALIGNOF(max_align_t);
259#endif
260}
261
262template <class... _Args>
263_LIBCPP_HIDE_FROM_ABI void* __libcpp_operator_new(_Args... __args) {
264#if __has_builtin(__builtin_operator_new) && __has_builtin(__builtin_operator_delete)
265  return __builtin_operator_new(__args...);
266#else
267  return ::operator new(__args...);
268#endif
269}
270
271template <class... _Args>
272_LIBCPP_HIDE_FROM_ABI void __libcpp_operator_delete(_Args... __args) {
273#if __has_builtin(__builtin_operator_new) && __has_builtin(__builtin_operator_delete)
274  __builtin_operator_delete(__args...);
275#else
276  ::operator delete(__args...);
277#endif
278}
279
280inline _LIBCPP_HIDE_FROM_ABI void* __libcpp_allocate(size_t __size, size_t __align) {
281#ifndef _LIBCPP_HAS_NO_ALIGNED_ALLOCATION
282  if (__is_overaligned_for_new(__align)) {
283    const align_val_t __align_val = static_cast<align_val_t>(__align);
284    return __libcpp_operator_new(__size, __align_val);
285  }
286#endif
287
288  (void)__align;
289  return __libcpp_operator_new(__size);
290}
291
292template <class... _Args>
293_LIBCPP_HIDE_FROM_ABI void __do_deallocate_handle_size(void* __ptr, size_t __size, _Args... __args) {
294#ifdef _LIBCPP_HAS_NO_SIZED_DEALLOCATION
295  (void)__size;
296  return std::__libcpp_operator_delete(__ptr, __args...);
297#else
298  return std::__libcpp_operator_delete(__ptr, __size, __args...);
299#endif
300}
301
302inline _LIBCPP_HIDE_FROM_ABI void __libcpp_deallocate(void* __ptr, size_t __size, size_t __align) {
303#if defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION)
304  (void)__align;
305  return __do_deallocate_handle_size(__ptr, __size);
306#else
307  if (__is_overaligned_for_new(__align)) {
308    const align_val_t __align_val = static_cast<align_val_t>(__align);
309    return __do_deallocate_handle_size(__ptr, __size, __align_val);
310  } else {
311    return __do_deallocate_handle_size(__ptr, __size);
312  }
313#endif
314}
315
316inline _LIBCPP_HIDE_FROM_ABI void __libcpp_deallocate_unsized(void* __ptr, size_t __align) {
317#if defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION)
318  (void)__align;
319  return __libcpp_operator_delete(__ptr);
320#else
321  if (__is_overaligned_for_new(__align)) {
322    const align_val_t __align_val = static_cast<align_val_t>(__align);
323    return __libcpp_operator_delete(__ptr, __align_val);
324  } else {
325    return __libcpp_operator_delete(__ptr);
326  }
327#endif
328}
329
330template <class _Tp>
331_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Tp* __launder(_Tp* __p) _NOEXCEPT {
332  static_assert(!(is_function<_Tp>::value), "can't launder functions");
333  static_assert(!(is_same<void, __remove_cv_t<_Tp> >::value), "can't launder cv-void");
334  return __builtin_launder(__p);
335}
336
337#if _LIBCPP_STD_VER >= 17
338template <class _Tp>
339[[nodiscard]] inline _LIBCPP_HIDE_FROM_ABI constexpr _Tp* launder(_Tp* __p) noexcept {
340  return std::__launder(__p);
341}
342#endif
343
344#if _LIBCPP_STD_VER >= 17
345
346#  if defined(__GCC_DESTRUCTIVE_SIZE) && defined(__GCC_CONSTRUCTIVE_SIZE)
347
348inline constexpr size_t hardware_destructive_interference_size  = __GCC_DESTRUCTIVE_SIZE;
349inline constexpr size_t hardware_constructive_interference_size = __GCC_CONSTRUCTIVE_SIZE;
350
351#  endif // defined(__GCC_DESTRUCTIVE_SIZE) && defined(__GCC_CONSTRUCTIVE_SIZE)
352
353#endif // _LIBCPP_STD_VER >= 17
354
355_LIBCPP_END_NAMESPACE_STD
356
357#if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20
358#  include <cstdlib>
359#  include <type_traits>
360#endif
361
362#endif // _LIBCPP_NEW
363