libc/test/src/math/smoke/atan2f_test.cpp

//===-- Unittests for atan2f ----------------------------------------------===//
//
// 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 "hdr/math_macros.h"
#include "src/__support/FPUtil/FPBits.h"
#include "src/math/atan2f.h"
#include "test/UnitTest/FPMatcher.h"
#include "test/UnitTest/Test.h"

using LlvmLibcAtan2fTest = LIBC_NAMESPACE::testing::FPTest<float>;

TEST_F(LlvmLibcAtan2fTest, SpecialNumbers) {
  constexpr float PI = 0x1.921fb6p+1f;
  constexpr float PI_OVER_2 = 0x1.921fb6p+0f;
  constexpr float PI_OVER_4 = 0x1.921fb6p-1f;
  constexpr float THREE_PI_OVER_4 = 0x1.2d97c8p+1f;

  EXPECT_FP_EQ(PI, LIBC_NAMESPACE::atan2f(zero, neg_zero));
  EXPECT_FP_EQ(-PI, LIBC_NAMESPACE::atan2f(neg_zero, neg_zero));
  EXPECT_FP_EQ(PI, LIBC_NAMESPACE::atan2f(zero, neg_inf));
  EXPECT_FP_EQ(-PI, LIBC_NAMESPACE::atan2f(neg_zero, neg_inf));
  EXPECT_FP_EQ(PI_OVER_2, LIBC_NAMESPACE::atan2f(inf, zero));
  EXPECT_FP_EQ(PI_OVER_2, LIBC_NAMESPACE::atan2f(inf, neg_zero));
  EXPECT_FP_EQ(-PI_OVER_2, LIBC_NAMESPACE::atan2f(neg_inf, zero));
  EXPECT_FP_EQ(-PI_OVER_2, LIBC_NAMESPACE::atan2f(neg_inf, neg_zero));
  EXPECT_FP_EQ(PI_OVER_4, LIBC_NAMESPACE::atan2f(inf, inf));
  EXPECT_FP_EQ(-PI_OVER_4, LIBC_NAMESPACE::atan2f(neg_inf, inf));
  EXPECT_FP_EQ(THREE_PI_OVER_4, LIBC_NAMESPACE::atan2f(inf, neg_inf));
  EXPECT_FP_EQ(-THREE_PI_OVER_4, LIBC_NAMESPACE::atan2f(neg_inf, neg_inf));

  EXPECT_FP_EQ_WITH_EXCEPTION(aNaN, LIBC_NAMESPACE::atan2f(sNaN, sNaN),
                              FE_INVALID);
  EXPECT_MATH_ERRNO(0);

  EXPECT_FP_EQ_WITH_EXCEPTION(aNaN, LIBC_NAMESPACE::atan2f(sNaN, 1.0f),
                              FE_INVALID);
  EXPECT_MATH_ERRNO(0);

  EXPECT_FP_EQ_WITH_EXCEPTION(aNaN, LIBC_NAMESPACE::atan2f(1.0f, sNaN),
                              FE_INVALID);
  EXPECT_MATH_ERRNO(0);

  // TODO: Strengthen errno,exception checks and remove these assert macros
  // after new matchers/test fixtures are added see:
  // https://github.com/llvm/llvm-project/issues/90653.
  LIBC_NAMESPACE::fputil::clear_except(FE_ALL_EXCEPT);
  EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::atan2f(aNaN, zero));
  // TODO: Uncomment these checks later, RoundingMode affects running
  // tests in this way https://github.com/llvm/llvm-project/issues/90653.
  // EXPECT_FP_EXCEPTION(0);
  EXPECT_MATH_ERRNO(0);

  LIBC_NAMESPACE::fputil::clear_except(FE_ALL_EXCEPT);
  EXPECT_FP_EQ_ALL_ROUNDING(aNaN, LIBC_NAMESPACE::atan2f(1.0f, aNaN));
  // See above TODO
  // EXPECT_FP_EXCEPTION(0);
  EXPECT_MATH_ERRNO(0);

  LIBC_NAMESPACE::fputil::clear_except(FE_ALL_EXCEPT);
  EXPECT_FP_EQ_ALL_ROUNDING(0.0f, LIBC_NAMESPACE::atan2f(zero, zero));
  // See above TODO
  // EXPECT_FP_EXCEPTION(0);
  EXPECT_MATH_ERRNO(0);

  LIBC_NAMESPACE::fputil::clear_except(FE_ALL_EXCEPT);
  EXPECT_FP_EQ_ALL_ROUNDING(-0.0f, LIBC_NAMESPACE::atan2f(-0.0f, zero));
  // See above TODO
  // EXPECT_FP_EXCEPTION(0);
  EXPECT_MATH_ERRNO(0);

  LIBC_NAMESPACE::fputil::clear_except(FE_ALL_EXCEPT);
  EXPECT_FP_EQ_ALL_ROUNDING(0.0f, LIBC_NAMESPACE::atan2f(1.0f, inf));
  // See above TODO
  // EXPECT_FP_EXCEPTION(0);
  EXPECT_MATH_ERRNO(0);

  LIBC_NAMESPACE::fputil::clear_except(FE_ALL_EXCEPT);
  EXPECT_FP_EQ_ALL_ROUNDING(-0.0f, LIBC_NAMESPACE::atan2f(-1.0f, inf));
  // See above TODO
  // EXPECT_FP_EXCEPTION(0);
  EXPECT_MATH_ERRNO(0);
}

#ifdef LIBC_TEST_FTZ_DAZ

using namespace LIBC_NAMESPACE::testing;

TEST_F(LlvmLibcAtan2fTest, FTZMode) {
  ModifyMXCSR mxcsr(FTZ);

  EXPECT_FP_EQ(0x1.921fb6p-1f,
               LIBC_NAMESPACE::atan2f(min_denormal, min_denormal));
  EXPECT_FP_EQ(0x1.000002p-23f,
               LIBC_NAMESPACE::atan2f(min_denormal, max_denormal));
  EXPECT_FP_EQ(0x1.921fb4p0f,
               LIBC_NAMESPACE::atan2f(max_denormal, min_denormal));
  EXPECT_FP_EQ(0x1.921fb6p-1f,
               LIBC_NAMESPACE::atan2f(max_denormal, max_denormal));
}

TEST_F(LlvmLibcAtan2fTest, DAZMode) {
  ModifyMXCSR mxcsr(DAZ);

  EXPECT_FP_EQ(0.0f, LIBC_NAMESPACE::atan2f(min_denormal, min_denormal));
  EXPECT_FP_EQ(0.0f, LIBC_NAMESPACE::atan2f(min_denormal, max_denormal));
  EXPECT_FP_EQ(0.0f, LIBC_NAMESPACE::atan2f(max_denormal, min_denormal));
  EXPECT_FP_EQ(0.0f, LIBC_NAMESPACE::atan2f(max_denormal, max_denormal));
}

TEST_F(LlvmLibcAtan2fTest, FTZDAZMode) {
  ModifyMXCSR mxcsr(FTZ | DAZ);

  EXPECT_FP_EQ(0.0f, LIBC_NAMESPACE::atan2f(min_denormal, min_denormal));
  EXPECT_FP_EQ(0.0f, LIBC_NAMESPACE::atan2f(min_denormal, max_denormal));
  EXPECT_FP_EQ(0.0f, LIBC_NAMESPACE::atan2f(max_denormal, min_denormal));
  EXPECT_FP_EQ(0.0f, LIBC_NAMESPACE::atan2f(max_denormal, max_denormal));
}

#endif