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 // UNSUPPORTED: c++03, c++11, c++14, c++17 10 11 // template <class T> 12 // constexpr bool has_single_bit(T x) noexcept; 13 14 // Constraints: T is an unsigned integer type 15 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 25 struct A {}; 26 enum E1 : unsigned char { rEd }; 27 enum class E2 : unsigned char { red }; 28 29 template <class T> 30 constexpr 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_INT128 52 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 #endif 69 70 return true; 71 } 72 73 int 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_INT128 85 static_assert(!std::is_invocable_v<L, __int128_t>); 86 #endif 87 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_T 100 static_assert(!std::is_invocable_v<L, char8_t>); 101 #endif 102 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_INT128 117 static_assert(test<__uint128_t>()); 118 #endif 119 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_INT128 133 test<__uint128_t>(); 134 #endif 135 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