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___PSTL_HANDLE_EXCEPTION_H
10#define _LIBCPP___PSTL_HANDLE_EXCEPTION_H
11
12#include <__config>
13#include <__new/exceptions.h>
14#include <__utility/forward.h>
15#include <__utility/move.h>
16#include <optional>
17
18#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
19# pragma GCC system_header
20#endif
21
22_LIBCPP_PUSH_MACROS
23#include <__undef_macros>
24
25#if _LIBCPP_STD_VER >= 17
26
27_LIBCPP_BEGIN_NAMESPACE_STD
28namespace __pstl {
29
30template <class _BackendFunction, class... _Args>
31_LIBCPP_HIDE_FROM_ABI auto __handle_exception_impl(_Args&&... __args) noexcept {
32 return _BackendFunction{}(std::forward<_Args>(__args)...);
33}
34
35// This function is used to call a backend PSTL algorithm from a frontend algorithm.
36//
37// All PSTL backend algorithms return an optional denoting whether there was an
38// "infrastructure"-level failure (aka failure to allocate). This function takes
39// care of unwrapping that and throwing `bad_alloc()` in case there was a problem
40// in the underlying implementation.
41//
42// We must also be careful not to call any user code that could throw an exception
43// (such as moving or copying iterators) in here since that should terminate the
44// program, which is why we delegate to a noexcept helper below.
45template <class _BackendFunction, class... _Args>
46_LIBCPP_HIDE_FROM_ABI auto __handle_exception(_Args&&... __args) {
47 auto __result = __pstl::__handle_exception_impl<_BackendFunction>(std::forward<_Args>(__args)...);
48 if (__result == nullopt)
49 std::__throw_bad_alloc();
50 else
51 return std::move(*__result);
52}
53
54} // namespace __pstl
55_LIBCPP_END_NAMESPACE_STD
56
57#endif // _LIBCPP_STD_VER >= 17
58
59_LIBCPP_POP_MACROS
60
61#endif // _LIBCPP___PSTL_HANDLE_EXCEPTION_H
62