1//===----------------------------------------------------------------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is dual licensed under the MIT and the University of Illinois Open 6// Source Licenses. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// UNSUPPORTED: c++98, c++03, c++11 11// <numeric> 12 13// template<class _M, class _N> 14// constexpr common_type_t<_M,_N> gcd(_M __m, _N __n) 15 16#include <experimental/numeric> 17#include <cassert> 18#include <cstdlib> 19#include <iostream> 20 21constexpr struct { 22 int x; 23 int y; 24 int expect; 25} Cases[] = { 26 {0, 0, 0}, 27 {1, 0, 0}, 28 {0, 1, 0}, 29 {1, 1, 1}, 30 {2, 3, 6}, 31 {2, 4, 4}, 32 {3, 17, 51}, 33 {36, 18, 36} 34}; 35 36template <typename Input1, typename Input2, typename Output> 37constexpr bool test0(Input1 in1, Input2 in2, Output out) 38{ 39 static_assert((std::is_same<Output, decltype(std::experimental::lcm(Input1(0), Input2(0)))>::value), "" ); 40 static_assert((std::is_same<Output, decltype(std::experimental::lcm(Input2(0), Input1(0)))>::value), "" ); 41 return out == std::experimental::lcm(in1, in2) ? true : (std::abort(), false); 42} 43 44 45template <typename Input1, typename Input2 = Input1> 46constexpr bool do_test(int = 0) 47{ 48 using S1 = typename std::make_signed<Input1>::type; 49 using S2 = typename std::make_signed<Input2>::type; 50 using U1 = typename std::make_unsigned<Input1>::type; 51 using U2 = typename std::make_unsigned<Input2>::type; 52 bool accumulate = true; 53 for (auto TC : Cases) { 54 { // Test with two signed types 55 using Output = std::common_type_t<S1, S2>; 56 accumulate &= test0<S1, S2, Output>(TC.x, TC.y, TC.expect); 57 accumulate &= test0<S1, S2, Output>(-TC.x, TC.y, TC.expect); 58 accumulate &= test0<S1, S2, Output>(TC.x, -TC.y, TC.expect); 59 accumulate &= test0<S1, S2, Output>(-TC.x, -TC.y, TC.expect); 60 accumulate &= test0<S2, S1, Output>(TC.x, TC.y, TC.expect); 61 accumulate &= test0<S2, S1, Output>(-TC.x, TC.y, TC.expect); 62 accumulate &= test0<S2, S1, Output>(TC.x, -TC.y, TC.expect); 63 accumulate &= test0<S2, S1, Output>(-TC.x, -TC.y, TC.expect); 64 } 65 { // test with two unsigned types 66 using Output = std::common_type_t<U1, U2>; 67 accumulate &= test0<U1, U2, Output>(TC.x, TC.y, TC.expect); 68 accumulate &= test0<U2, U1, Output>(TC.x, TC.y, TC.expect); 69 } 70 { // Test with mixed signs 71 using Output = std::common_type_t<S1, U2>; 72 accumulate &= test0<S1, U2, Output>(TC.x, TC.y, TC.expect); 73 accumulate &= test0<U2, S1, Output>(TC.x, TC.y, TC.expect); 74 accumulate &= test0<S1, U2, Output>(-TC.x, TC.y, TC.expect); 75 accumulate &= test0<U2, S1, Output>(TC.x, -TC.y, TC.expect); 76 } 77 { // Test with mixed signs 78 using Output = std::common_type_t<S2, U1>; 79 accumulate &= test0<S2, U1, Output>(TC.x, TC.y, TC.expect); 80 accumulate &= test0<U1, S2, Output>(TC.x, TC.y, TC.expect); 81 accumulate &= test0<S2, U1, Output>(-TC.x, TC.y, TC.expect); 82 accumulate &= test0<U1, S2, Output>(TC.x, -TC.y, TC.expect); 83 } 84 } 85 return accumulate; 86} 87 88int main() 89{ 90 auto non_cce = std::rand(); // a value that can't possibly be constexpr 91 92 static_assert(do_test<signed char>(), ""); 93 static_assert(do_test<short>(), ""); 94 static_assert(do_test<int>(), ""); 95 static_assert(do_test<long>(), ""); 96 static_assert(do_test<long long>(), ""); 97 98 assert(do_test<signed char>(non_cce)); 99 assert(do_test<short>(non_cce)); 100 assert(do_test<int>(non_cce)); 101 assert(do_test<long>(non_cce)); 102 assert(do_test<long long>(non_cce)); 103 104 static_assert(do_test< int8_t>(), ""); 105 static_assert(do_test<int16_t>(), ""); 106 static_assert(do_test<int32_t>(), ""); 107 static_assert(do_test<int64_t>(), ""); 108 109 assert(do_test< int8_t>(non_cce)); 110 assert(do_test<int16_t>(non_cce)); 111 assert(do_test<int32_t>(non_cce)); 112 assert(do_test<int64_t>(non_cce)); 113 114 static_assert(do_test<signed char, int>(), ""); 115 static_assert(do_test<int, signed char>(), ""); 116 static_assert(do_test<short, int>(), ""); 117 static_assert(do_test<int, short>(), ""); 118 static_assert(do_test<int, long>(), ""); 119 static_assert(do_test<long, int>(), ""); 120 static_assert(do_test<int, long long>(), ""); 121 static_assert(do_test<long long, int>(), ""); 122 123 assert((do_test<signed char, int>(non_cce))); 124 assert((do_test<int, signed char>(non_cce))); 125 assert((do_test<short, int>(non_cce))); 126 assert((do_test<int, short>(non_cce))); 127 assert((do_test<int, long>(non_cce))); 128 assert((do_test<long, int>(non_cce))); 129 assert((do_test<int, long long>(non_cce))); 130 assert((do_test<long long, int>(non_cce))); 131 132// LWG#2792 133 { 134 auto res1 = std::experimental::lcm((int64_t)1234, (int32_t)-2147483648); 135 (void) std::experimental::lcm<int, unsigned long>(INT_MIN, 2); // this used to trigger UBSAN 136 static_assert( std::is_same<decltype(res1), std::common_type<int64_t, int32_t>::type>::value, ""); 137 assert(res1 == 1324997410816LL); 138 } 139} 140