unittests/Support/TypeTraitsTest.cpp

//===- TypeTraitsTest.cpp -------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//

#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/FunctionExtras.h"
#include "llvm/ADT/PointerIntPair.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/type_traits.h"
#include "gtest/gtest.h"
#include <optional>

namespace {

// Compile-time tests using static assert.
namespace triviality {

// Helper for compile time checking trivially copy constructible and trivially
// move constructible type traits.
template <typename T, bool IsTriviallyCopyConstructible,
          bool IsTriviallyMoveConstructible>
void TrivialityTester() {
  static_assert(llvm::is_trivially_copy_constructible<T>::value ==
                    IsTriviallyCopyConstructible,
                "Mismatch in expected trivial copy construction!");
  static_assert(llvm::is_trivially_move_constructible<T>::value ==
                    IsTriviallyMoveConstructible,
                "Mismatch in expected trivial move construction!");

#if defined(_LIBCPP_VERSION) || defined(_MSC_VER)
  // On compilers with support for the standard traits, make sure they agree.
  static_assert(std::is_trivially_copy_constructible<T>::value ==
                    IsTriviallyCopyConstructible,
                "Mismatch in expected trivial copy construction!");
  static_assert(std::is_trivially_move_constructible<T>::value ==
                    IsTriviallyMoveConstructible,
                "Mismatch in expected trivial move construction!");
#endif
}

template void TrivialityTester<int, true, true>();
template void TrivialityTester<void *, true, true>();
template void TrivialityTester<int &, true, true>();
template void TrivialityTester<int &&, false, true>();

struct X {};
struct Y {
  Y(const Y &);
};
struct Z {
  Z(const Z &);
  Z(Z &&);
};
struct A {
  A(const A &) = default;
  A(A &&);
};
struct B {
  B(const B &);
  B(B &&) = default;
};

template void TrivialityTester<X, true, true>();
template void TrivialityTester<Y, false, false>();
template void TrivialityTester<Z, false, false>();
template void TrivialityTester<A, true, false>();
template void TrivialityTester<B, false, true>();

template void TrivialityTester<Z &, true, true>();
template void TrivialityTester<A &, true, true>();
template void TrivialityTester<B &, true, true>();
template void TrivialityTester<Z &&, false, true>();
template void TrivialityTester<A &&, false, true>();
template void TrivialityTester<B &&, false, true>();

TEST(Triviality, Tester) {
  TrivialityTester<int, true, true>();
  TrivialityTester<void *, true, true>();
  TrivialityTester<int &, true, true>();
  TrivialityTester<int &&, false, true>();

  TrivialityTester<X, true, true>();
  TrivialityTester<Y, false, false>();
  TrivialityTester<Z, false, false>();
  TrivialityTester<A, true, false>();
  TrivialityTester<B, false, true>();

  TrivialityTester<Z &, true, true>();
  TrivialityTester<A &, true, true>();
  TrivialityTester<B &, true, true>();
  TrivialityTester<Z &&, false, true>();
  TrivialityTester<A &&, false, true>();
  TrivialityTester<B &&, false, true>();
}

// Test that the following ADT behave as expected wrt. trivially copyable trait
//
// NB: It is important that this trait behaves the same for (at least) these
// types for all supported compilers to prevent ABI issue when llvm is compiled
// with compiler A and an other project using llvm is compiled with compiler B.

TEST(Triviality, ADT) {

  TrivialityTester<llvm::SmallVector<int>, false, false>();
  TrivialityTester<llvm::SmallString<8>, false, false>();

  TrivialityTester<std::function<int()>, false, false>();
#if !defined(__FreeBSD__)
  TrivialityTester<std::pair<int, bool>, true, true>();
#endif
  TrivialityTester<llvm::unique_function<int()>, false, false>();
  TrivialityTester<llvm::StringRef, true, true>();
  TrivialityTester<llvm::ArrayRef<int>, true, true>();
  TrivialityTester<llvm::PointerIntPair<int *, 2>, true, true>();
#if defined(_LIBCPP_VERSION) ||                                                \
    (defined(_GLIBCXX_RELEASE) && _GLIBCXX_RELEASE >= 8)
  TrivialityTester<std::optional<int>, true, true>();
#endif
}

} // namespace triviality

} // end anonymous namespace