| //===----------------------------------------------------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is dual licensed under the MIT and the University of Illinois Open |
| // Source Licenses. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // UNSUPPORTED: c++98, c++03, c++11, c++14, c++17 |
| |
| // template <class T> |
| // constexpr int countl_one(T x) noexcept; |
| |
| // The number of consecutive 1 bits, starting from the most significant bit. |
| // [ Note: Returns N if x == std::numeric_limits<T>::max(). ] |
| // |
| // Remarks: This function shall not participate in overload resolution unless |
| // T is an unsigned integer type |
| |
| #include <bit> |
| #include <cstdint> |
| #include <type_traits> |
| #include <cassert> |
| |
| #include "test_macros.h" |
| |
| class A{}; |
| enum E1 : unsigned char { rEd }; |
| enum class E2 : unsigned char { red }; |
| |
| template <typename T> |
| constexpr bool constexpr_test() |
| { |
| const int dig = std::numeric_limits<T>::digits; |
| const T max = std::numeric_limits<T>::max(); |
| return std::countl_one(max) == dig |
| && std::countl_one(T(max - 1)) == dig - 1 |
| && std::countl_one(T(max - 2)) == dig - 2 |
| && std::countl_one(T(max - 3)) == dig - 2 |
| && std::countl_one(T(max - 4)) == dig - 3 |
| && std::countl_one(T(max - 5)) == dig - 3 |
| && std::countl_one(T(max - 6)) == dig - 3 |
| && std::countl_one(T(max - 7)) == dig - 3 |
| && std::countl_one(T(max - 8)) == dig - 4 |
| && std::countl_one(T(max - 9)) == dig - 4 |
| ; |
| } |
| |
| |
| template <typename T> |
| void runtime_test() |
| { |
| ASSERT_SAME_TYPE(int, decltype(std::countl_one(T(0)))); |
| ASSERT_NOEXCEPT( std::countl_one(T(0))); |
| const int dig = std::numeric_limits<T>::digits; |
| |
| assert( std::countl_one(T(~121)) == dig - 7); |
| assert( std::countl_one(T(~122)) == dig - 7); |
| assert( std::countl_one(T(~123)) == dig - 7); |
| assert( std::countl_one(T(~124)) == dig - 7); |
| assert( std::countl_one(T(~125)) == dig - 7); |
| assert( std::countl_one(T(~126)) == dig - 7); |
| assert( std::countl_one(T(~127)) == dig - 7); |
| assert( std::countl_one(T(~128)) == dig - 8); |
| assert( std::countl_one(T(~129)) == dig - 8); |
| assert( std::countl_one(T(~130)) == dig - 8); |
| } |
| |
| int main() |
| { |
| { |
| auto lambda = [](auto x) -> decltype(std::countl_one(x)) {}; |
| using L = decltype(lambda); |
| |
| static_assert( std::is_invocable_v<L, unsigned char>, ""); |
| static_assert( std::is_invocable_v<L, unsigned int>, ""); |
| static_assert( std::is_invocable_v<L, unsigned long>, ""); |
| static_assert( std::is_invocable_v<L, unsigned long long>, ""); |
| |
| static_assert( std::is_invocable_v<L, uint8_t>, ""); |
| static_assert( std::is_invocable_v<L, uint16_t>, ""); |
| static_assert( std::is_invocable_v<L, uint32_t>, ""); |
| static_assert( std::is_invocable_v<L, uint64_t>, ""); |
| static_assert( std::is_invocable_v<L, size_t>, ""); |
| |
| static_assert( std::is_invocable_v<L, uintmax_t>, ""); |
| static_assert( std::is_invocable_v<L, uintptr_t>, ""); |
| |
| |
| static_assert(!std::is_invocable_v<L, int>, ""); |
| static_assert(!std::is_invocable_v<L, signed int>, ""); |
| static_assert(!std::is_invocable_v<L, long>, ""); |
| static_assert(!std::is_invocable_v<L, long long>, ""); |
| |
| static_assert(!std::is_invocable_v<L, int8_t>, ""); |
| static_assert(!std::is_invocable_v<L, int16_t>, ""); |
| static_assert(!std::is_invocable_v<L, int32_t>, ""); |
| static_assert(!std::is_invocable_v<L, int64_t>, ""); |
| static_assert(!std::is_invocable_v<L, ptrdiff_t>, ""); |
| |
| static_assert(!std::is_invocable_v<L, bool>, ""); |
| static_assert(!std::is_invocable_v<L, signed char>, ""); |
| static_assert(!std::is_invocable_v<L, char16_t>, ""); |
| static_assert(!std::is_invocable_v<L, char32_t>, ""); |
| |
| #ifndef _LIBCPP_HAS_NO_INT128 |
| static_assert( std::is_invocable_v<L, __uint128_t>, ""); |
| static_assert(!std::is_invocable_v<L, __int128_t>, ""); |
| #endif |
| |
| static_assert(!std::is_invocable_v<L, A>, ""); |
| static_assert(!std::is_invocable_v<L, E1>, ""); |
| static_assert(!std::is_invocable_v<L, E2>, ""); |
| } |
| |
| static_assert(constexpr_test<unsigned char>(), ""); |
| static_assert(constexpr_test<unsigned short>(), ""); |
| static_assert(constexpr_test<unsigned>(), ""); |
| static_assert(constexpr_test<unsigned long>(), ""); |
| static_assert(constexpr_test<unsigned long long>(), ""); |
| |
| static_assert(constexpr_test<uint8_t>(), ""); |
| static_assert(constexpr_test<uint16_t>(), ""); |
| static_assert(constexpr_test<uint32_t>(), ""); |
| static_assert(constexpr_test<uint64_t>(), ""); |
| static_assert(constexpr_test<size_t>(), ""); |
| static_assert(constexpr_test<uintmax_t>(), ""); |
| static_assert(constexpr_test<uintptr_t>(), ""); |
| |
| #ifndef _LIBCPP_HAS_NO_INT128 |
| static_assert(constexpr_test<__uint128_t>(), ""); |
| #endif |
| |
| |
| runtime_test<unsigned char>(); |
| runtime_test<unsigned>(); |
| runtime_test<unsigned short>(); |
| runtime_test<unsigned long>(); |
| runtime_test<unsigned long long>(); |
| |
| runtime_test<uint8_t>(); |
| runtime_test<uint16_t>(); |
| runtime_test<uint32_t>(); |
| runtime_test<uint64_t>(); |
| runtime_test<size_t>(); |
| runtime_test<uintmax_t>(); |
| runtime_test<uintptr_t>(); |
| |
| #ifndef _LIBCPP_HAS_NO_INT128 |
| runtime_test<__uint128_t>(); |
| |
| { |
| const int dig = std::numeric_limits<__uint128_t>::digits; |
| __uint128_t val = 128; |
| |
| val <<= 32; |
| assert( std::countl_one(~val) == dig - 40); |
| val <<= 2; |
| assert( std::countl_one(~val) == dig - 42); |
| val <<= 3; |
| assert( std::countl_one(~val) == dig - 45); |
| } |
| #endif |
| |
| } |