blob: 2ab41c18225e451b7f9f0dbb7eb446fbae1a6cbd [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
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++98, c++03, c++11, c++14, c++17
// <cmath>
// constexpr float lerp(float a, float b, float t);
// constexpr double lerp(double a, double b, double t);
// constexpr long double lerp(long double a, long double b, long double t);
#include <cmath>
#include <limits>
#include <type_traits>
#include <cassert>
#include "test_macros.h"
#include "fp_compare.h"
template <typename T>
constexpr bool constexpr_test()
{
return std::lerp(T( 0), T(12), T(0)) == T(0)
&& std::lerp(T(12), T( 0), T(0.5)) == T(6)
&& std::lerp(T( 0), T(12), T(2)) == T(24);
}
template <typename T>
void test()
{
ASSERT_SAME_TYPE(T, decltype(std::lerp(T(), T(), T())));
LIBCPP_ASSERT_NOEXCEPT( std::lerp(T(), T(), T()));
// constexpr T minV = std::numeric_limits<T>::min();
constexpr T maxV = std::numeric_limits<T>::max();
constexpr T inf = std::numeric_limits<T>::infinity();
// Things that can be compared exactly
assert((std::lerp(T( 0), T(12), T(0)) == T(0)));
assert((std::lerp(T( 0), T(12), T(1)) == T(12)));
assert((std::lerp(T(12), T( 0), T(0)) == T(12)));
assert((std::lerp(T(12), T( 0), T(1)) == T(0)));
assert((std::lerp(T( 0), T(12), T(0.5)) == T(6)));
assert((std::lerp(T(12), T( 0), T(0.5)) == T(6)));
assert((std::lerp(T( 0), T(12), T(2)) == T(24)));
assert((std::lerp(T(12), T( 0), T(2)) == T(-12)));
assert((std::lerp(maxV, maxV/10, T(0)) == maxV));
assert((std::lerp(maxV/10, maxV, T(1)) == maxV));
assert((std::lerp(T(2.3), T(2.3), inf) == T(2.3)));
assert(std::lerp(T( 0), T( 0), T(23)) == T(0));
assert(std::isnan(std::lerp(T( 0), T( 0), inf)));
}
int main(int, char**)
{
static_assert(constexpr_test<float>(), "");
static_assert(constexpr_test<double>(), "");
static_assert(constexpr_test<long double>(), "");
test<float>();
test<double>();
test<long double>();
return 0;
}