llvm-project/libcxx/test/support/fp_compare.h

47 lines
1.4 KiB
C++

//===----------------------------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
#ifndef SUPPORT_FP_COMPARE_H
#define SUPPORT_FP_COMPARE_H
#include <cmath> // for std::abs
#include <algorithm> // for std::max
#include <cassert>
// See https://www.boost.org/doc/libs/1_70_0/libs/test/doc/html/boost_test/testing_tools/extended_comparison/floating_point/floating_points_comparison_theory.html
template<typename T>
bool fptest_close(T val, T expected, T eps)
{
constexpr T zero = T(0);
assert(eps >= zero);
// Handle the zero cases
if (eps == zero) return val == expected;
if (val == zero) return std::abs(expected) <= eps;
if (expected == zero) return std::abs(val) <= eps;
return std::abs(val - expected) < eps
&& std::abs(val - expected)/std::abs(val) < eps;
}
template<typename T>
bool fptest_close_pct(T val, T expected, T percent)
{
constexpr T zero = T(0);
assert(percent >= zero);
// Handle the zero cases
if (percent == zero) return val == expected;
T eps = (percent / T(100)) * std::max(std::abs(val), std::abs(expected));
return fptest_close(val, expected, eps);
}
#endif // SUPPORT_FP_COMPARE_H