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//===----------------------------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
// <vector>
// Make sure we don't miscompile vector operations for types that shouldn't be considered
// trivially relocatable.
#include <vector>
#include <cassert>
#include <cstddef>
#include <type_traits>
#include <utility>
#include "test_macros.h"
struct Tracker {
std::size_t move_constructs = 0;
};
struct [[clang::trivial_abi]] Inner {
TEST_CONSTEXPR_CXX20 explicit Inner(Tracker* tracker) : tracker_(tracker) {}
TEST_CONSTEXPR_CXX20 Inner(const Inner& rhs) : tracker_(rhs.tracker_) { tracker_->move_constructs += 1; }
TEST_CONSTEXPR_CXX20 Inner(Inner&& rhs) : tracker_(rhs.tracker_) { tracker_->move_constructs += 1; }
Tracker* tracker_;
};
// Even though this type contains a trivial_abi type, it is not trivially move-constructible,
// so we should not attempt to optimize its move construction + destroy using trivial relocation.
struct NotTriviallyMovable {
TEST_CONSTEXPR_CXX20 explicit NotTriviallyMovable(Tracker* tracker) : inner_(tracker) {}
TEST_CONSTEXPR_CXX20 NotTriviallyMovable(NotTriviallyMovable&& other) : inner_(std::move(other.inner_)) {}
Inner inner_;
};
static_assert(!std::is_trivially_copyable<NotTriviallyMovable>::value, "");
LIBCPP_STATIC_ASSERT(!std::__libcpp_is_trivially_relocatable<NotTriviallyMovable>::value, "");
TEST_CONSTEXPR_CXX20 bool tests() {
Tracker track;
std::vector<NotTriviallyMovable> v;
// Fill the vector at its capacity, such that any subsequent push_back would require growing.
v.reserve(5);
std::size_t const capacity = v.capacity(); // could technically be more than 5
while (v.size() < v.capacity()) {
v.emplace_back(&track);
}
assert(track.move_constructs == 0);
assert(v.capacity() == capacity);
assert(v.size() == capacity);
// Force a reallocation of the buffer + relocalization of the elements.
// All the existing elements of the vector should be move-constructed to their new location.
v.emplace_back(&track);
assert(track.move_constructs == capacity);
return true;
}
int main(int, char**) {
tests();
#if TEST_STD_VER >= 20
static_assert(tests());
#endif
return 0;
}
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