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 29 template <class _Alloc> 30 [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr 31 allocation_result<typename allocator_traits<_Alloc>::pointer> allocate_at_least(_Alloc& __alloc, size_t __n) { 32 if constexpr (requires { __alloc.allocate_at_least(__n); }) { 33 return __alloc.allocate_at_least(__n); 34 } else { 35 return {__alloc.allocate(__n), __n}; 36 } 37 } 38 39 template <class _Alloc> 40 [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr 41 auto __allocate_at_least(_Alloc& __alloc, size_t __n) { 42 return std::allocate_at_least(__alloc, __n); 43 } 44 #else 45 template <class _Pointer> 46 struct __allocation_result { 47 _Pointer ptr; 48 size_t count; 49 }; 50 51 template <class _Alloc> 52 _LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR 53 __allocation_result<typename allocator_traits<_Alloc>::pointer> __allocate_at_least(_Alloc& __alloc, size_t __n) { 54 return {__alloc.allocate(__n), __n}; 55 } 56 57 #endif // _LIBCPP_STD_VER > 20 58 59 _LIBCPP_END_NAMESPACE_STD 60 61 #endif // _LIBCPP___MEMORY_ALLOCATE_AT_LEAST_H 62