text: //===-- Floating point classification functions -----------------*- 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 LLVM_LIBC_UTILS_FPUTIL_CLASSIFICATION_FUNCTIONS_H
  #define LLVM_LIBC_UTILS_FPUTIL_CLASSIFICATION_FUNCTIONS_H
  
  #include "BitPatterns.h"
  #include "FloatOperations.h"
  #include "FloatProperties.h"
  
  #include "utils/CPP/TypeTraits.h"
  
  namespace __llvm_libc {
  namespace fputil {
  
  template <typename BitsType> static inline bool bitsAreInf(BitsType bits) {
    using FPType = typename FloatType<BitsType>::Type;
    return ((bits & BitPatterns<FPType>::inf) == BitPatterns<FPType>::inf) &&
           ((bits & FloatProperties<FPType>::mantissaMask) == 0);
  }
  
  // Return true if x is infinity (positive or negative.)
  template <typename T,
            cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
  static inline bool isInf(T x) {
    return bitsAreInf(valueAsBits(x));
  }
  
  template <typename BitsType> static inline bool bitsAreNaN(BitsType bits) {
    using FPType = typename FloatType<BitsType>::Type;
    return ((bits & BitPatterns<FPType>::inf) == BitPatterns<FPType>::inf) &&
           ((bits & FloatProperties<FPType>::mantissaMask) != 0);
  }
  
  // Return true if x is a NAN (quiet or signalling.)
  template <typename T,
            cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
  static inline bool isNaN(T x) {
    return bitsAreNaN(valueAsBits(x));
  }
  
  template <typename BitsType> static inline bool bitsAreInfOrNaN(BitsType bits) {
    using FPType = typename FloatType<BitsType>::Type;
    return (bits & BitPatterns<FPType>::inf) == BitPatterns<FPType>::inf;
  }
  
  template <typename BitsType> static inline bool bitsAreZero(BitsType bits) {
    using FPType = typename FloatType<BitsType>::Type;
    return (bits == BitPatterns<FPType>::zero) ||
           (bits == BitPatterns<FPType>::negZero);
  }
  
  // Return true if x is any kind of NaN or infinity.
  template <typename T,
            cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
  static inline bool isInfOrNaN(T x) {
    return bitsAreInfOrNaN(valueAsBits(x));
  }
  
  // Return true if x is a quiet NAN.
  template <typename T,
            cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
  static inline bool isQuietNaN(T x) {
    using Properties = FloatProperties<T>;
    using BitsType = typename FloatProperties<T>::BitsType;
    BitsType bits = valueAsBits(x);
    return ((bits & BitPatterns<T>::inf) == BitPatterns<T>::inf) &&
           ((bits & Properties::quietNaNMask) != 0);
  }
  
  // Return true if x is a quiet NAN with sign bit set.
  template <typename T,
            cpp::EnableIfType<cpp::IsFloatingPointType<T>::Value, int> = 0>
  static inline bool isNegativeQuietNaN(T x) {
    using Properties = FloatProperties<T>;
    using BitsType = typename FloatProperties<T>::BitsType;
    BitsType bits = valueAsBits(x);
    return ((bits & BitPatterns<T>::negInf) == BitPatterns<T>::negInf) &&
           ((bits & Properties::quietNaNMask) != 0);
  }
  
  } // namespace fputil
  } // namespace __llvm_libc
  
  #endif // LLVM_LIBC_UTILS_FPUTIL_CLASSIFICATION_FUNCTIONS_H
  