91 lines
2.2 KiB
C++
91 lines
2.2 KiB
C++
/*
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* Copyright (c) Facebook, Inc. and its affiliates.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#pragma once
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#include <cmath>
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namespace folly {
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#if !defined(__ANDROID__) && !defined(__UCLIBC__)
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/**
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* Most platforms hopefully provide std::nextafter, std::remainder.
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*/
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/* using override */ using std::nextafter;
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/* using override */ using std::remainder;
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#else // !__ANDROID__ && !__UCLIBC__
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/**
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* On Android and uclibc, std::nextafter or std::remainder isn't implemented.
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* However, the C functions and compiler builtins are still provided. Using the
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* GCC builtin is actually slightly faster, as they're constexpr and the use
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* cases within folly are in constexpr context.
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*/
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#if defined(__GNUC__) && !defined(__clang__)
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constexpr float nextafter(float x, float y) {
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return __builtin_nextafterf(x, y);
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}
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constexpr double nextafter(double x, double y) {
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return __builtin_nextafter(x, y);
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}
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constexpr long double nextafter(long double x, long double y) {
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return __builtin_nextafterl(x, y);
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}
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#else // __GNUC__
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inline float nextafter(float x, float y) {
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return ::nextafterf(x, y);
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}
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inline double nextafter(double x, double y) {
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return ::nextafter(x, y);
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}
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inline long double nextafter(long double x, long double y) {
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return ::nextafterl(x, y);
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}
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#endif // __GNUC__
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/**
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* On uclibc, std::remainder isn't implemented.
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* Implement it using builtin versions
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*/
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#ifdef __UCLIBC__
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constexpr float remainder(float x, float y) {
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return __builtin_remainderf(x, y);
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}
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constexpr double remainder(double x, double y) {
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return __builtin_remainder(x, y);
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}
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constexpr long double remainder(long double x, long double y) {
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return __builtin_remainderl(x, y);
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}
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#endif // __UCLIBC__
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#endif // !__ANDROID__ && !__UCLIBC__
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} // namespace folly
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