1 //===----------------------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef _LIBCPP___MEMORY_ALLOCATE_AT_LEAST_H 10 #define _LIBCPP___MEMORY_ALLOCATE_AT_LEAST_H 11 12 #include <__config> 13 #include <__memory/allocator_traits.h> 14 #include <cstddef> 15 16 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 17 # pragma GCC system_header 18 #endif 19 20 _LIBCPP_BEGIN_NAMESPACE_STD 21 22 #if _LIBCPP_STD_VER > 20 23 template <class _Pointer> 24 struct allocation_result { 25 _Pointer ptr; 26 size_t count; 27 }; 28 _LIBCPP_CTAD_SUPPORTED_FOR_TYPE(allocation_result); 29 30 template <class _Alloc> 31 [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr allocate_at_least(_Alloc & __alloc,size_t __n)32allocation_result<typename allocator_traits<_Alloc>::pointer> allocate_at_least(_Alloc& __alloc, size_t __n) { 33 if constexpr (requires { __alloc.allocate_at_least(__n); }) { 34 return __alloc.allocate_at_least(__n); 35 } else { 36 return {__alloc.allocate(__n), __n}; 37 } 38 } 39 40 template <class _Alloc> 41 [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr __allocate_at_least(_Alloc & __alloc,size_t __n)42auto __allocate_at_least(_Alloc& __alloc, size_t __n) { 43 return std::allocate_at_least(__alloc, __n); 44 } 45 #else 46 template <class _Pointer> 47 struct __allocation_result { 48 _Pointer ptr; 49 size_t count; 50 }; 51 52 template <class _Alloc> 53 _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR 54 __allocation_result<typename allocator_traits<_Alloc>::pointer> __allocate_at_least(_Alloc& __alloc, size_t __n) { 55 return {__alloc.allocate(__n), __n}; 56 } 57 58 #endif // _LIBCPP_STD_VER > 20 59 60 _LIBCPP_END_NAMESPACE_STD 61 62 #endif // _LIBCPP___MEMORY_ALLOCATE_AT_LEAST_H 63