libcxx/test/std/numerics/bit/bitops.rot/rotr.pass.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-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 // UNSUPPORTED: c++03, c++11, c++14, c++17
  10
  11 // template <class T>
  12 //   constexpr int rotr(T x, unsigned int s) noexcept;
  13
  14 // Constraints: T is an unsigned integer type
  15
  16 #include <bit>
  17 #include <cassert>
  18 #include <cstdint>
  19 #include <limits>
  20 #include <type_traits>
  21
  22 #include "test_macros.h"
  23
  24 struct A {};
  25 enum       E1 : unsigned char { rEd };
  26 enum class E2 : unsigned char { red };
  27
  28 template <class T>
  29 constexpr bool test()
  30 {
  31     ASSERT_SAME_TYPE(decltype(std::rotr(T(), 0)), T);
  32     ASSERT_NOEXCEPT(std::rotr(T(), 0));
  33     T max = std::numeric_limits<T>::max();
  34     T highbit = std::rotr(T(1), 1);
  35
  36     assert(std::rotr(T(max - 1), 0) == T(max - 1));
  37     assert(std::rotr(T(max - 1), 1) == T(max - highbit));
  38     assert(std::rotr(T(max - 1), 2) == T(max - (highbit >> 1)));
  39     assert(std::rotr(T(max - 1), 3) == T(max - (highbit >> 2)));
  40     assert(std::rotr(T(max - 1), 4) == T(max - (highbit >> 3)));
  41     assert(std::rotr(T(max - 1), 5) == T(max - (highbit >> 4)));
  42     assert(std::rotr(T(max - 1), 6) == T(max - (highbit >> 5)));
  43     assert(std::rotr(T(max - 1), 7) == T(max - (highbit >> 6)));
  44
  45     assert(std::rotr(T(max - 1), -1) == T(max - 2));
  46     assert(std::rotr(T(max - 1), -2) == T(max - 4));
  47     assert(std::rotr(T(max - 1), -3) == T(max - 8));
  48     assert(std::rotr(T(max - 1), -4) == T(max - 16));
  49     assert(std::rotr(T(max - 1), -5) == T(max - 32));
  50     assert(std::rotr(T(max - 1), -6) == T(max - 64));
  51     assert(std::rotr(T(max - 1), -7) == T(max - 128));
  52
  53     assert(std::rotr(T(128), 0) == T(128));
  54     assert(std::rotr(T(128), 1) == T(64));
  55     assert(std::rotr(T(128), 2) == T(32));
  56     assert(std::rotr(T(128), 3) == T(16));
  57     assert(std::rotr(T(128), 4) == T(8));
  58     assert(std::rotr(T(128), 5) == T(4));
  59     assert(std::rotr(T(128), 6) == T(2));
  60     assert(std::rotr(T(128), 7) == T(1));
  61
  62     assert(std::rotr(T(1), -1) == T(2));
  63     assert(std::rotr(T(1), -2) == T(4));
  64     assert(std::rotr(T(1), -3) == T(8));
  65     assert(std::rotr(T(1), -4) == T(16));
  66     assert(std::rotr(T(1), -5) == T(32));
  67     assert(std::rotr(T(1), -6) == T(64));
  68     assert(std::rotr(T(1), -7) == T(128));
  69
  70 #ifndef TEST_HAS_NO_INT128
  71     if constexpr (std::is_same_v<T, __uint128_t>) {
  72         T val = (T(1) << 63) | (T(1) << 64);
  73         assert(std::rotr(val, 0) == val);
  74         assert(std::rotr(val, 128) == val);
  75         assert(std::rotr(val, 256) == val);
  76         assert(std::rotr(val, 1) == val >> 1);
  77         assert(std::rotr(val, 127) == val << 1);
  78         assert(std::rotr(T(3), 1) == ((T(1) << 127) | T(1)));
  79
  80         assert(std::rotr(val, -128) == val);
  81         assert(std::rotr(val, -256) == val);
  82         assert(std::rotr(val, -1) == val << 1);
  83         assert(std::rotr(val, -127) == val >> 1);
  84         assert(std::rotr(T(3), -127) == ((T(1) << 127) | T(1)));
  85     }
  86 #endif
  87
  88     return true;
  89 }
  90
  91 int main(int, char**)
  92 {
  93     {
  94     auto lambda = [](auto x) -> decltype(std::rotl(x, 1U)) {};
  95     using L = decltype(lambda);
  96
  97     static_assert(!std::is_invocable_v<L, signed char>);
  98     static_assert(!std::is_invocable_v<L, short>);
  99     static_assert(!std::is_invocable_v<L, int>);
 100     static_assert(!std::is_invocable_v<L, long>);
 101     static_assert(!std::is_invocable_v<L, long long>);
 102 #ifndef TEST_HAS_NO_INT128
 103     static_assert(!std::is_invocable_v<L, __int128_t>);
 104 #endif
 105
 106     static_assert(!std::is_invocable_v<L, std::int8_t>);
 107     static_assert(!std::is_invocable_v<L, std::int16_t>);
 108     static_assert(!std::is_invocable_v<L, std::int32_t>);
 109     static_assert(!std::is_invocable_v<L, std::int64_t>);
 110     static_assert(!std::is_invocable_v<L, std::intmax_t>);
 111     static_assert(!std::is_invocable_v<L, std::intptr_t>);
 112     static_assert(!std::is_invocable_v<L, std::ptrdiff_t>);
 113
 114     static_assert(!std::is_invocable_v<L, bool>);
 115     static_assert(!std::is_invocable_v<L, char>);
 116     static_assert(!std::is_invocable_v<L, wchar_t>);
 117 #ifndef TEST_HAS_NO_CHAR8_T
 118     static_assert(!std::is_invocable_v<L, char8_t>);
 119 #endif
 120     static_assert(!std::is_invocable_v<L, char16_t>);
 121     static_assert(!std::is_invocable_v<L, char32_t>);
 122
 123     static_assert(!std::is_invocable_v<L, A>);
 124     static_assert(!std::is_invocable_v<L, A*>);
 125     static_assert(!std::is_invocable_v<L, E1>);
 126     static_assert(!std::is_invocable_v<L, E2>);
 127     }
 128
 129     static_assert(test<unsigned char>());
 130     static_assert(test<unsigned short>());
 131     static_assert(test<unsigned int>());
 132     static_assert(test<unsigned long>());
 133     static_assert(test<unsigned long long>());
 134 #ifndef TEST_HAS_NO_INT128
 135     static_assert(test<__uint128_t>());
 136 #endif
 137
 138     static_assert(test<std::uint8_t>());
 139     static_assert(test<std::uint16_t>());
 140     static_assert(test<std::uint32_t>());
 141     static_assert(test<std::uint64_t>());
 142     static_assert(test<std::uintmax_t>());
 143     static_assert(test<std::uintptr_t>());
 144     static_assert(test<std::size_t>());
 145
 146     test<unsigned char>();
 147     test<unsigned short>();
 148     test<unsigned int>();
 149     test<unsigned long>();
 150     test<unsigned long long>();
 151 #ifndef TEST_HAS_NO_INT128
 152     test<__uint128_t>();
 153 #endif
 154
 155     test<std::uint8_t>();
 156     test<std::uint16_t>();
 157     test<std::uint32_t>();
 158     test<std::uint64_t>();
 159     test<std::uintmax_t>();
 160     test<std::uintptr_t>();
 161     test<std::size_t>();
 162
 163     return 0;
 164 }