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//===----------------------------------------------------------------------===//
//
// 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++03, c++11, c++14, c++17
// template <class T>
// constexpr int countl_zero(T x) noexcept;
// Constraints: T is an unsigned integer type
// Returns: The number of consecutive 0 bits, starting from the most significant bit.
// [ Note: Returns N if x == 0. ]
#include <bit>
#include <cassert>
#include <cstdint>
#include <type_traits>
#include "test_macros.h"
struct A {};
enum E1 : unsigned char { rEd };
enum class E2 : unsigned char { red };
template <class T>
constexpr bool test()
{
ASSERT_SAME_TYPE(decltype(std::countl_zero(T())), int);
ASSERT_NOEXCEPT(std::countl_zero(T()));
T max = std::numeric_limits<T>::max();
int dig = std::numeric_limits<T>::digits;
assert(std::countl_zero(T(0)) == dig);
assert(std::countl_zero(T(1)) == dig - 1);
assert(std::countl_zero(T(2)) == dig - 2);
assert(std::countl_zero(T(3)) == dig - 2);
assert(std::countl_zero(T(4)) == dig - 3);
assert(std::countl_zero(T(5)) == dig - 3);
assert(std::countl_zero(T(6)) == dig - 3);
assert(std::countl_zero(T(7)) == dig - 3);
assert(std::countl_zero(T(8)) == dig - 4);
assert(std::countl_zero(T(9)) == dig - 4);
assert(std::countl_zero(T(127)) == dig - 7);
assert(std::countl_zero(T(128)) == dig - 8);
assert(std::countl_zero(max) == 0);
#ifndef TEST_HAS_NO_INT128
if constexpr (std::is_same_v<T, __uint128_t>) {
T val = T(128) << 32;
assert(std::countl_zero(val-1) == 89);
assert(std::countl_zero(val) == 88);
assert(std::countl_zero(val+1) == 88);
val <<= 60;
assert(std::countl_zero(val-1) == 29);
assert(std::countl_zero(val) == 28);
assert(std::countl_zero(val+1) == 28);
}
#endif
return true;
}
int main(int, char**)
{
{
auto lambda = [](auto x) -> decltype(std::countl_zero(x)) {};
using L = decltype(lambda);
static_assert(!std::is_invocable_v<L, signed char>);
static_assert(!std::is_invocable_v<L, short>);
static_assert(!std::is_invocable_v<L, int>);
static_assert(!std::is_invocable_v<L, long>);
static_assert(!std::is_invocable_v<L, long long>);
#ifndef TEST_HAS_NO_INT128
static_assert(!std::is_invocable_v<L, __int128_t>);
#endif
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, intmax_t>);
static_assert(!std::is_invocable_v<L, intptr_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, char>);
static_assert(!std::is_invocable_v<L, wchar_t>);
#ifndef TEST_HAS_NO_CHAR8_T
static_assert(!std::is_invocable_v<L, char8_t>);
#endif
static_assert(!std::is_invocable_v<L, char16_t>);
static_assert(!std::is_invocable_v<L, char32_t>);
static_assert(!std::is_invocable_v<L, A>);
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(test<unsigned char>());
static_assert(test<unsigned short>());
static_assert(test<unsigned int>());
static_assert(test<unsigned long>());
static_assert(test<unsigned long long>());
#ifndef TEST_HAS_NO_INT128
static_assert(test<__uint128_t>());
#endif
static_assert(test<uint8_t>());
static_assert(test<uint16_t>());
static_assert(test<uint32_t>());
static_assert(test<uint64_t>());
static_assert(test<uintmax_t>());
static_assert(test<uintptr_t>());
static_assert(test<size_t>());
test<unsigned char>();
test<unsigned short>();
test<unsigned int>();
test<unsigned long>();
test<unsigned long long>();
#ifndef TEST_HAS_NO_INT128
test<__uint128_t>();
#endif
test<uint8_t>();
test<uint16_t>();
test<uint32_t>();
test<uint64_t>();
test<uintmax_t>();
test<uintptr_t>();
test<size_t>();
return 0;
}
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