text: //===-- Unittests for modfl -----------------------------------------------===//
  //
  // 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
  //
  //===----------------------------------------------------------------------===//
  
  #include "src/math/modfl.h"
  #include "utils/FPUtil/BasicOperations.h"
  #include "utils/FPUtil/FPBits.h"
  #include "utils/FPUtil/NearestIntegerOperations.h"
  #include "utils/UnitTest/Test.h"
  #include <math.h>
  
  using FPBits = __llvm_libc::fputil::FPBits<long double>;
  
  TEST(modflTest, SpecialNumbers) {
    long double integral;
  
    EXPECT_TRUE(FPBits::zero() == __llvm_libc::modfl(FPBits::inf(), &integral));
    EXPECT_TRUE(FPBits::inf() == integral);
  
    EXPECT_TRUE(FPBits::negZero() ==
                __llvm_libc::modfl(FPBits::negInf(), &integral));
    EXPECT_TRUE(FPBits::negInf() == integral);
  
    EXPECT_TRUE(FPBits::zero() == __llvm_libc::modfl(FPBits::zero(), &integral));
    EXPECT_TRUE(integral == 0.0l);
  
    EXPECT_TRUE(FPBits::negZero() ==
                __llvm_libc::modfl(FPBits::negZero(), &integral));
    EXPECT_TRUE(integral == 0.0l);
  
    EXPECT_TRUE(
        FPBits(__llvm_libc::modfl(FPBits::buildNaN(1), &integral)).isNaN());
  }
  
  TEST(modflTest, Integers) {
    long double integral;
  
    EXPECT_TRUE(FPBits::zero() == __llvm_libc::modfl(1.0l, &integral));
    EXPECT_TRUE(integral == 1.0l);
  
    EXPECT_TRUE(FPBits::negZero() == __llvm_libc::modfl(-1.0l, &integral));
    EXPECT_TRUE(integral == -1.0l);
  
    EXPECT_TRUE(FPBits::zero() == __llvm_libc::modfl(10.0l, &integral));
    EXPECT_TRUE(integral == 10.0l);
  
    EXPECT_TRUE(FPBits::negZero() == __llvm_libc::modfl(-10.0l, &integral));
    EXPECT_TRUE(integral == -10.0l);
  
    EXPECT_TRUE(FPBits::zero() == __llvm_libc::modfl(12345.0l, &integral));
    EXPECT_TRUE(integral == 12345.0l);
  
    EXPECT_TRUE(FPBits::negZero() == __llvm_libc::modfl(-12345.0l, &integral));
    EXPECT_TRUE(integral == -12345.0l);
  }
  
  TEST(ModfTest, Fractions) {
    long double integral;
  
    EXPECT_TRUE(0.5l == __llvm_libc::modfl(1.5l, &integral));
    EXPECT_TRUE(integral == 1.0l);
  
    EXPECT_TRUE(-0.5l == __llvm_libc::modfl(-1.5l, &integral));
    EXPECT_TRUE(integral == -1.0l);
  
    EXPECT_TRUE(0.75l == __llvm_libc::modfl(10.75l, &integral));
    EXPECT_TRUE(integral == 10.0l);
  
    EXPECT_TRUE(-0.75l == __llvm_libc::modfl(-10.75l, &integral));
    EXPECT_TRUE(integral == -10.0l);
  
    EXPECT_TRUE(0.125l == __llvm_libc::modfl(100.125l, &integral));
    EXPECT_TRUE(integral == 100.0l);
  
    EXPECT_TRUE(-0.125l == __llvm_libc::modfl(-100.125l, &integral));
    EXPECT_TRUE(integral == -100.0l);
  }
  
  TEST(ModflTest, LongDoubleRange) {
    using UIntType = FPBits::UIntType;
    constexpr UIntType count = 10000000;
    constexpr UIntType step = UIntType(-1) / count;
    for (UIntType i = 0, v = 0; i <= count; ++i, v += step) {
      long double x = FPBits(v);
      if (isnan(x) || isinf(x) || x == 0.0l)
        continue;
  
      long double integral;
      long double frac = __llvm_libc::modfl(x, &integral);
      ASSERT_TRUE(__llvm_libc::fputil::abs(frac) < 1.0l);
      ASSERT_TRUE(__llvm_libc::fputil::trunc(x) == integral);
      ASSERT_TRUE(integral + frac == x);
    }
  }
  