145 lines · cpp
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-exception6//7//===----------------------------------------------------------------------===//8 9// UNSUPPORTED: c++03, c++11, c++14, c++1710 11// template <class T>12// constexpr bool has_single_bit(T x) noexcept;13 14// Constraints: T is an unsigned integer type15 16#include <bit>17#include <cassert>18#include <cstddef>19#include <cstdint>20#include <limits>21#include <type_traits>22 23#include "test_macros.h"24 25struct A {};26enum E1 : unsigned char { rEd };27enum class E2 : unsigned char { red };28 29template <class T>30constexpr bool test()31{32 ASSERT_SAME_TYPE(decltype(std::has_single_bit(T())), bool);33 ASSERT_NOEXCEPT(std::has_single_bit(T()));34 T max = std::numeric_limits<T>::max();35 36 assert(!std::has_single_bit(T(0)));37 assert( std::has_single_bit(T(1)));38 assert( std::has_single_bit(T(2)));39 assert(!std::has_single_bit(T(3)));40 assert( std::has_single_bit(T(4)));41 assert(!std::has_single_bit(T(5)));42 assert(!std::has_single_bit(T(6)));43 assert(!std::has_single_bit(T(7)));44 assert( std::has_single_bit(T(8)));45 assert(!std::has_single_bit(T(9)));46 assert(!std::has_single_bit(T(127)));47 assert( std::has_single_bit(T(128)));48 assert(!std::has_single_bit(T(129)));49 assert(!std::has_single_bit(max));50 51#ifndef TEST_HAS_NO_INT12852 if constexpr (std::is_same_v<T, __uint128_t>) {53 T val = T(1) << 32;54 assert(!std::has_single_bit(val-1));55 assert( std::has_single_bit(val));56 assert(!std::has_single_bit(val+1));57 val <<= 60;58 assert(!std::has_single_bit(val-1));59 assert( std::has_single_bit(val));60 assert(!std::has_single_bit(val+1));61 62 T x = (T(1) << 63);63 T y = (T(1) << 64);64 assert( std::has_single_bit(x));65 assert( std::has_single_bit(y));66 assert(!std::has_single_bit(x + y));67 }68#endif69 70 return true;71}72 73int main(int, char**)74{75 {76 auto lambda = [](auto x) -> decltype(std::has_single_bit(x)) {};77 using L = decltype(lambda);78 79 static_assert(!std::is_invocable_v<L, signed char>);80 static_assert(!std::is_invocable_v<L, short>);81 static_assert(!std::is_invocable_v<L, int>);82 static_assert(!std::is_invocable_v<L, long>);83 static_assert(!std::is_invocable_v<L, long long>);84#ifndef TEST_HAS_NO_INT12885 static_assert(!std::is_invocable_v<L, __int128_t>);86#endif87 88 static_assert(!std::is_invocable_v<L, std::int8_t>);89 static_assert(!std::is_invocable_v<L, std::int16_t>);90 static_assert(!std::is_invocable_v<L, std::int32_t>);91 static_assert(!std::is_invocable_v<L, std::int64_t>);92 static_assert(!std::is_invocable_v<L, std::intmax_t>);93 static_assert(!std::is_invocable_v<L, std::intptr_t>);94 static_assert(!std::is_invocable_v<L, std::ptrdiff_t>);95 96 static_assert(!std::is_invocable_v<L, bool>);97 static_assert(!std::is_invocable_v<L, char>);98 static_assert(!std::is_invocable_v<L, wchar_t>);99#ifndef TEST_HAS_NO_CHAR8_T100 static_assert(!std::is_invocable_v<L, char8_t>);101#endif102 static_assert(!std::is_invocable_v<L, char16_t>);103 static_assert(!std::is_invocable_v<L, char32_t>);104 105 static_assert(!std::is_invocable_v<L, A>);106 static_assert(!std::is_invocable_v<L, A*>);107 static_assert(!std::is_invocable_v<L, E1>);108 static_assert(!std::is_invocable_v<L, E2>);109 }110 111 static_assert(test<unsigned char>());112 static_assert(test<unsigned short>());113 static_assert(test<unsigned int>());114 static_assert(test<unsigned long>());115 static_assert(test<unsigned long long>());116#ifndef TEST_HAS_NO_INT128117 static_assert(test<__uint128_t>());118#endif119 static_assert(test<std::uint8_t>());120 static_assert(test<std::uint16_t>());121 static_assert(test<std::uint32_t>());122 static_assert(test<std::uint64_t>());123 static_assert(test<std::uintmax_t>());124 static_assert(test<std::uintptr_t>());125 static_assert(test<std::size_t>());126 127 test<unsigned char>();128 test<unsigned short>();129 test<unsigned int>();130 test<unsigned long>();131 test<unsigned long long>();132#ifndef TEST_HAS_NO_INT128133 test<__uint128_t>();134#endif135 test<std::uint8_t>();136 test<std::uint16_t>();137 test<std::uint32_t>();138 test<std::uint64_t>();139 test<std::uintmax_t>();140 test<std::uintptr_t>();141 test<std::size_t>();142 143 return 0;144}145