You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
This repo is archived. You can view files and clone it, but cannot push or open issues/pull-requests.
libcxx_old/test/libcxx/utilities/optional/optional.object/triviality.abi.pass.cpp

102 lines
4.3 KiB
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
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++98, c++03, c++11, c++14
// <optional>
// This test asserts the triviality of special member functions of optional<T>
// whenever T has these special member functions trivial. The goal of this test
// is to make sure that we do not change the triviality of those, since that
// constitues an ABI break (small enough optionals would be passed by registers).
//
// constexpr optional(const optional& rhs);
// constexpr optional(optional&& rhs) noexcept(see below);
// constexpr optional<T>& operator=(const optional& rhs);
// constexpr optional<T>& operator=(optional&& rhs) noexcept(see below);
#include <optional>
#include <type_traits>
#include <cassert>
#include "archetypes.hpp"
#include "test_macros.h"
template <class T>
struct SpecialMemberTest {
using O = std::optional<T>;
static_assert(std::is_trivially_destructible_v<O> ==
std::is_trivially_destructible_v<T>,
"optional<T> is trivially destructible if and only if T is.");
static_assert(std::is_trivially_copy_constructible_v<O> ==
std::is_trivially_copy_constructible_v<T>,
"optional<T> is trivially copy constructible if and only if T is.");
static_assert(std::is_trivially_move_constructible_v<O> ==
std::is_trivially_move_constructible_v<T> ||
(!std::is_move_constructible_v<T> && std::is_trivially_copy_constructible_v<T>),
"optional<T> is trivially move constructible if T is trivially move constructible, "
"or if T is trivially copy constructible and is not move constructible.");
static_assert(std::is_trivially_copy_assignable_v<O> ==
(std::is_trivially_destructible_v<T> &&
std::is_trivially_copy_constructible_v<T> &&
std::is_trivially_copy_assignable_v<T>),
"optional<T> is trivially copy assignable if and only if T is trivially destructible, "
"trivially copy constructible, and trivially copy assignable.");
static_assert(std::is_trivially_move_assignable_v<O> ==
(std::is_trivially_destructible_v<T> &&
((std::is_trivially_move_constructible_v<T> && std::is_trivially_move_assignable_v<T>) ||
((!std::is_move_constructible_v<T> || !std::is_move_assignable_v<T>) &&
std::is_trivially_copy_constructible_v<T> && std::is_trivially_copy_assignable_v<T>))),
"optional<T> is trivially move assignable if T is trivially destructible, and either "
"(1) trivially move constructible and trivially move assignable, or "
"(2) not move constructible or not move assignable, and "
"trivially copy constructible and trivially copy assignable.");
};
template <class ...Args> static void sink(Args&&...) {}
template <class ...TestTypes>
struct DoTestsMetafunction {
DoTestsMetafunction() { sink(SpecialMemberTest<TestTypes>{}...); }
};
struct TrivialMoveNonTrivialCopy {
TrivialMoveNonTrivialCopy() = default;
TrivialMoveNonTrivialCopy(const TrivialMoveNonTrivialCopy&) {}
TrivialMoveNonTrivialCopy(TrivialMoveNonTrivialCopy&&) = default;
TrivialMoveNonTrivialCopy& operator=(const TrivialMoveNonTrivialCopy&) { return *this; }
TrivialMoveNonTrivialCopy& operator=(TrivialMoveNonTrivialCopy&&) = default;
};
struct TrivialCopyNonTrivialMove {
TrivialCopyNonTrivialMove() = default;
TrivialCopyNonTrivialMove(const TrivialCopyNonTrivialMove&) = default;
TrivialCopyNonTrivialMove(TrivialCopyNonTrivialMove&&) {}
TrivialCopyNonTrivialMove& operator=(const TrivialCopyNonTrivialMove&) = default;
TrivialCopyNonTrivialMove& operator=(TrivialCopyNonTrivialMove&&) { return *this; }
};
int main(int, char**)
{
sink(
ImplicitTypes::ApplyTypes<DoTestsMetafunction>{},
ExplicitTypes::ApplyTypes<DoTestsMetafunction>{},
NonLiteralTypes::ApplyTypes<DoTestsMetafunction>{},
NonTrivialTypes::ApplyTypes<DoTestsMetafunction>{},
DoTestsMetafunction<TrivialMoveNonTrivialCopy, TrivialCopyNonTrivialMove>{}
);
return 0;
}