// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//==============================================================================
// NOTICE: This file has been modified by Green Hills Software, Inc.  Such
// modifications are subject to copyright by Green Hills Software, Inc.  See the
// "Green Hills Software Modifications" section in the LICENSE.txt included with
// this distribution for more information.
//==============================================================================

#ifndef _LIBCPP___MEMORY_TEMPORARY_BUFFER_H
#define _LIBCPP___MEMORY_TEMPORARY_BUFFER_H

#include <__config>
#include <__type_traits/alignment_of.h>
#include <__utility/pair.h>
#include <cstddef>
#include <new>

#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#  pragma GCC system_header
#endif

#if defined(__ghs__)
  #pragma ghs start_cxx_lib_header
  #pragma ghs startdata
  #if defined(__ghs_max_pack_value)
    #pragma pack (push, __ghs_max_pack_value)
  #endif
#endif

_LIBCPP_BEGIN_NAMESPACE_STD

template <class _Tp>
_LIBCPP_NODISCARD_EXT _GHS_LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_CFI _LIBCPP_DEPRECATED_IN_CXX17
pair<_Tp*, ptrdiff_t>
#if defined(__ghs__)
__get_temporary_buffer(ptrdiff_t __n) _NOEXCEPT
#else
get_temporary_buffer(ptrdiff_t __n) _NOEXCEPT
#endif
{
    pair<_Tp*, ptrdiff_t> __r(0, 0);
    const ptrdiff_t __m = (~ptrdiff_t(0) ^
                           ptrdiff_t(ptrdiff_t(1) << (sizeof(ptrdiff_t) * __CHAR_BIT__ - 1)))
                           / sizeof(_Tp);
    if (__n > __m)
        __n = __m;
    while (__n > 0)
    {
#if !defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION)
    if (__is_overaligned_for_new(_LIBCPP_ALIGNOF(_Tp)))
        {
            align_val_t __al =
                align_val_t(alignment_of<_Tp>::value);
            __r.first = static_cast<_Tp*>(::operator new(
                __n * sizeof(_Tp), __al, nothrow));
        } else {
            __r.first = static_cast<_Tp*>(::operator new(
                __n * sizeof(_Tp), nothrow));
        }
#else
    if (__is_overaligned_for_new(_LIBCPP_ALIGNOF(_Tp)))
        {
            // Since aligned operator new is unavailable, return an empty
            // buffer rather than one with invalid alignment.
            return __r;
        }

        __r.first = static_cast<_Tp*>(::operator new(__n * sizeof(_Tp), nothrow));
#endif

        if (__r.first)
        {
            __r.second = __n;
            break;
        }
        __n /= 2;
    }
    return __r;
}

template <class _Tp>
inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_DEPRECATED_IN_CXX17
#if defined(__ghs__)
void __return_temporary_buffer(_Tp* __p)
#else
void return_temporary_buffer(_Tp* __p)
#endif
#ifndef __ghs__
_NOEXCEPT
#else
_LIBCPP_NOEXCEPT_AFTER_CXX14
#endif
{
  _VSTD::__libcpp_deallocate_unsized((void*)__p, _LIBCPP_ALIGNOF(_Tp));
}

#if defined(__ghs__) && _LIBCPP_STD_VER <= 17
// {get, return}_temporary_buffer was removed in C++20
template <class _Tp>
_LIBCPP_NODISCARD_EXT _GHS_LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_CFI _LIBCPP_DEPRECATED_IN_CXX17
pair<_Tp*, ptrdiff_t>
get_temporary_buffer(ptrdiff_t __n) _NOEXCEPT
{
    return std::__get_temporary_buffer<_Tp>(__n);
}

template <class _Tp>
inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_DEPRECATED_IN_CXX17
void return_temporary_buffer(_Tp* __p)
#ifndef __ghs__
_NOEXCEPT
#else
_LIBCPP_NOEXCEPT_AFTER_CXX14
#endif
{
    return std::__return_temporary_buffer(__p);
}
#endif

#if defined(__ghs__)
struct __return_temporary_buffer_obj
#else
struct __return_temporary_buffer
#endif
{
_LIBCPP_SUPPRESS_DEPRECATED_PUSH
    template <class _Tp>
#if defined(__ghs__)
    _LIBCPP_INLINE_VISIBILITY void operator()(_Tp* __p) const {_VSTD::__return_temporary_buffer(__p);}
#else
    _LIBCPP_INLINE_VISIBILITY void operator()(_Tp* __p) const {_VSTD::return_temporary_buffer(__p);}
#endif
_LIBCPP_SUPPRESS_DEPRECATED_POP
};

_LIBCPP_END_NAMESPACE_STD

#if defined(__ghs__)
  #if defined(__ghs_max_pack_value)
    #pragma pack(pop)
  #endif
  #pragma ghs enddata
  #pragma ghs end_cxx_lib_header
#endif

#endif // _LIBCPP___MEMORY_TEMPORARY_BUFFER_H