blob: cb3336f52ba2077c0d93b8e69cffd3e67d7fa80b [file] [log] [blame]
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// __clamp_to_integral<IntT>(RealT)
// Test the conversion function that truncates floating point types to the
// closest representable value for the specified integer type, or
// numeric_limits<IntT>::max()/min() if the value isn't representable.
#include <limits>
#include <cassert>
#include <cmath>
template <class IntT>
void test() {
typedef std::numeric_limits<IntT> Lim;
const bool MaxIsRepresentable = sizeof(IntT) < 8;
const bool IsSigned = std::is_signed<IntT>::value;
struct TestCase {
double Input;
IntT Expect;
bool IsRepresentable;
} TestCases[] = {
{0, 0, true},
{1, 1, true},
{IsSigned ? static_cast<IntT>(-1) : 0,
IsSigned ? static_cast<IntT>(-1) : 0, true},
{Lim::lowest(), Lim::lowest(), true},
{static_cast<double>(Lim::max()), Lim::max(), MaxIsRepresentable},
{static_cast<double>(Lim::max()) + 1, Lim::max(), false},
{static_cast<double>(Lim::max()) + 1024, Lim::max(), false},
{nextafter(static_cast<double>(Lim::max()), INFINITY), Lim::max(), false},
};
for (TestCase TC : TestCases) {
auto res = std::__clamp_to_integral<IntT>(TC.Input);
assert(res == TC.Expect);
if (TC.IsRepresentable) {
auto other = static_cast<IntT>(std::trunc(TC.Input));
assert(res == other);
} else
assert(res == Lim::min() || res == Lim::max());
}
}
template <class IntT>
void test_float() {
typedef std::numeric_limits<IntT> Lim;
const bool MaxIsRepresentable = sizeof(IntT) < 4;
((void)MaxIsRepresentable);
const bool IsSigned = std::is_signed<IntT>::value;
struct TestCase {
float Input;
IntT Expect;
bool IsRepresentable;
} TestCases[] = {
{0, 0, true},
{1, 1, true},
{IsSigned ? static_cast<IntT>(-1) : 0,
IsSigned ? static_cast<IntT>(-1) : 0, true},
{Lim::lowest(), Lim::lowest(), true},
{static_cast<float>(Lim::max()), Lim::max(), MaxIsRepresentable },
{nextafter(static_cast<float>(Lim::max()), INFINITY), Lim::max(), false},
};
for (TestCase TC : TestCases) {
auto res = std::__clamp_to_integral<IntT>(TC.Input);
assert(res == TC.Expect);
if (TC.IsRepresentable) {
auto other = static_cast<IntT>(std::trunc(TC.Input));
assert(res == other);
} else
assert(res == Lim::min() || res == Lim::max());
}
}
int main() {
test<short>();
test<unsigned short>();
test<int>();
test<unsigned>();
test<long long>();
test<unsigned long long>();
test_float<short>();
test_float<int>();
test_float<long long>();
}