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1//===-- FPMatchers.h --------------------------------------------*- C++ -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef LLVM_LIBC_TEST_UNITTEST_FPMATCHER_H10#define LLVM_LIBC_TEST_UNITTEST_FPMATCHER_H11 12#include "src/__support/CPP/array.h"13#include "src/__support/CPP/type_traits.h"14#include "src/__support/FPUtil/FEnvImpl.h"15#include "src/__support/FPUtil/FPBits.h"16#include "src/__support/FPUtil/fpbits_str.h"17#include "src/__support/libc_errno.h"18#include "src/__support/macros/config.h"19#include "src/__support/macros/optimization.h"20#include "src/__support/macros/properties/architectures.h"21#include "test/UnitTest/ErrnoCheckingTest.h"22#include "test/UnitTest/RoundingModeUtils.h"23#include "test/UnitTest/StringUtils.h"24#include "test/UnitTest/Test.h"25 26#include "hdr/math_macros.h"27 28using LIBC_NAMESPACE::Sign;29 30namespace LIBC_NAMESPACE_DECL {31namespace testing {32 33template <typename T, TestCond Condition> class FPMatcher : public Matcher<T> {34  static_assert(cpp::is_floating_point_v<T>,35                "FPMatcher can only be used with floating point values.");36  static_assert(Condition == TestCond::EQ || Condition == TestCond::NE,37                "Unsupported FPMatcher test condition.");38 39  T expected;40  T actual;41 42public:43  FPMatcher(T expectedValue) : expected(expectedValue) {}44 45  bool match(T actualValue) {46    actual = actualValue;47    fputil::FPBits<T> actualBits(actual), expectedBits(expected);48    if (Condition == TestCond::EQ)49      return (actualBits.is_nan() && expectedBits.is_nan()) ||50             (actualBits.uintval() == expectedBits.uintval());51 52    // If condition == TestCond::NE.53    if (actualBits.is_nan())54      return !expectedBits.is_nan();55    return expectedBits.is_nan() ||56           (actualBits.uintval() != expectedBits.uintval());57  }58 59  void explainError() override {60    tlog << "Expected floating point value: "61         << str(fputil::FPBits<T>(expected)) << '\n';62    tlog << "Actual floating point value: " << str(fputil::FPBits<T>(actual))63         << '\n';64  }65};66 67template <typename T, TestCond Condition> class CFPMatcher : public Matcher<T> {68  static_assert(69      cpp::is_complex_v<T>,70      "CFPMatcher can only be used with complex floating point values.");71  static_assert(Condition == TestCond::EQ || Condition == TestCond::NE,72                "Unsupported CFPMatcher test condition.");73 74  T expected;75  T actual;76 77public:78  CFPMatcher(T expectedValue) : expected(expectedValue) {}79 80  template <typename CFT> bool matchComplex() {81    CFT *actualCmplxPtr = reinterpret_cast<CFT *>(&actual);82    CFT *expectedCmplxPtr = reinterpret_cast<CFT *>(&expected);83    CFT actualReal = actualCmplxPtr[0];84    CFT actualImag = actualCmplxPtr[1];85    CFT expectedReal = expectedCmplxPtr[0];86    CFT expectedImag = expectedCmplxPtr[1];87    fputil::FPBits<CFT> actualRealBits(actualReal),88        expectedRealBits(expectedReal);89    fputil::FPBits<CFT> actualImagBits(actualImag),90        expectedImagBits(expectedImag);91    if (Condition == TestCond::EQ)92      return ((actualRealBits.is_nan() && expectedRealBits.is_nan()) ||93              (actualRealBits.uintval() == expectedRealBits.uintval())) &&94             ((actualImagBits.is_nan() && expectedImagBits.is_nan()) ||95              (actualImagBits.uintval() == expectedImagBits.uintval()));96 97    // If condition == TestCond::NE.98    if (actualRealBits.is_nan() && expectedRealBits.is_nan())99      return !expectedRealBits.is_nan() && !expectedImagBits.is_nan();100    if (actualRealBits.is_nan())101      return !expectedRealBits.is_nan();102    if (actualImagBits.is_nan())103      return !expectedImagBits.is_nan();104    return (expectedRealBits.is_nan() ||105            actualRealBits.uintval() != expectedRealBits.uintval()) &&106           (expectedImagBits.is_nan() ||107            actualImagBits.uintval() != expectedImagBits.uintval());108  }109 110  template <typename CFT> void explainErrorComplex() {111    CFT *actualCmplxPtr = reinterpret_cast<CFT *>(&actual);112    CFT *expectedCmplxPtr = reinterpret_cast<CFT *>(&expected);113    CFT actualReal = actualCmplxPtr[0];114    CFT actualImag = actualCmplxPtr[1];115    CFT expectedReal = expectedCmplxPtr[0];116    CFT expectedImag = expectedCmplxPtr[1];117    tlog << "Expected complex floating point value: "118         << str(fputil::FPBits<CFT>(expectedReal)) + " + " +119                str(fputil::FPBits<CFT>(expectedImag)) + "i"120         << '\n';121    tlog << "Actual complex floating point value: "122         << str(fputil::FPBits<CFT>(actualReal)) + " + " +123                str(fputil::FPBits<CFT>(actualImag)) + "i"124         << '\n';125  }126 127  bool match(T actualValue) {128    actual = actualValue;129#ifndef LIBC_COMPILER_IS_MSVC130    if constexpr (cpp::is_complex_type_same<T, _Complex float>())131      return matchComplex<float>();132    else if constexpr (cpp::is_complex_type_same<T, _Complex double>())133      return matchComplex<double>();134    else if constexpr (cpp::is_complex_type_same<T, _Complex long double>())135      return matchComplex<long double>();136#ifdef LIBC_TYPES_HAS_CFLOAT16137    else if constexpr (cpp::is_complex_type_same<T, cfloat16>())138      return matchComplex<float16>();139#endif // LIBC_TYPES_HAS_CFLOAT16140#ifdef LIBC_TYPES_HAS_CFLOAT128141    else if constexpr (cpp::is_complex_type_same<T, cfloat128>())142      return matchComplex<float128>();143#endif // LIBC_TYPES_HAS_CFLOAT128144#else  // LIBC_COMPILER_IS_MSVC145    return true;146#endif // LIBC_COMPILER_IS_MSVC147  }148 149  void explainError() override {150#ifndef LIBC_COMPILER_IS_MSVC151    if constexpr (cpp::is_complex_type_same<T, _Complex float>())152      return explainErrorComplex<float>();153    else if constexpr (cpp::is_complex_type_same<T, _Complex double>())154      return explainErrorComplex<double>();155    else if constexpr (cpp::is_complex_type_same<T, _Complex long double>())156      return explainErrorComplex<long double>();157#ifdef LIBC_TYPES_HAS_CFLOAT16158    else if constexpr (cpp::is_complex_type_same<T, cfloat16>())159      return explainErrorComplex<float16>();160#endif // LIBC_TYPES_HAS_CFLOAT16161#ifdef LIBC_TYPES_HAS_CFLOAT128162    else if constexpr (cpp::is_complex_type_same<T, cfloat128>())163      return explainErrorComplex<float128>();164#endif // LIBC_TYPES_HAS_CFLOAT128165#endif // LIBC_COMPILER_IS_MSVC166  }167};168 169template <TestCond C, typename T> FPMatcher<T, C> getMatcher(T expectedValue) {170  return FPMatcher<T, C>(expectedValue);171}172 173template <TestCond C, typename T>174CFPMatcher<T, C> getMatcherComplex(T expectedValue) {175  return CFPMatcher<T, C>(expectedValue);176}177 178template <typename T> struct FPTest : public ErrnoCheckingTest {179  using FPBits = LIBC_NAMESPACE::fputil::FPBits<T>;180  using StorageType = typename FPBits::StorageType;181  static constexpr StorageType STORAGE_MAX =182      LIBC_NAMESPACE::cpp::numeric_limits<StorageType>::max();183  static constexpr T zero = FPBits::zero(Sign::POS).get_val();184  static constexpr T neg_zero = FPBits::zero(Sign::NEG).get_val();185  static constexpr T aNaN = FPBits::quiet_nan(Sign::POS).get_val();186  static constexpr T neg_aNaN = FPBits::quiet_nan(Sign::NEG).get_val();187  // TODO: make this static constexpr188  const T sNaN = FPBits::signaling_nan().get_val();189  static constexpr T inf = FPBits::inf(Sign::POS).get_val();190  static constexpr T neg_inf = FPBits::inf(Sign::NEG).get_val();191  static constexpr T min_normal = FPBits::min_normal().get_val();192  static constexpr T max_normal = FPBits::max_normal(Sign::POS).get_val();193  static constexpr T neg_max_normal = FPBits::max_normal(Sign::NEG).get_val();194  static constexpr T min_denormal = FPBits::min_subnormal().get_val();195  static constexpr T max_denormal = FPBits::max_subnormal().get_val();196 197  static constexpr int N_ROUNDING_MODES = 4;198  static constexpr fputil::testing::RoundingMode ROUNDING_MODES[4] = {199      fputil::testing::RoundingMode::Nearest,200      fputil::testing::RoundingMode::Upward,201      fputil::testing::RoundingMode::Downward,202      fputil::testing::RoundingMode::TowardZero,203  };204 205  void TearDown() override {206    // TODO (PR 135320): Remove this override once all FPTest instances are207    // updated to validate or ignore errno.208    libc_errno = 0;209    ErrnoCheckingTest::TearDown();210  }211};212 213// Add facility to test Flush-Denormal-To-Zero (FTZ) and Denormal-As-Zero (DAZ)214// modes.215// These tests to ensure that our implementations will not crash under these216// modes.217#if defined(LIBC_TARGET_ARCH_IS_X86_64) && __has_builtin(__builtin_ia32_stmxcsr)218 219#define LIBC_TEST_FTZ_DAZ220 221static constexpr unsigned FTZ = 0x8000; // Flush denormal to zero222static constexpr unsigned DAZ = 0x0040; // Denormal as zero223 224struct ModifyMXCSR {225  ModifyMXCSR(unsigned flags) {226    old_mxcsr = __builtin_ia32_stmxcsr();227    __builtin_ia32_ldmxcsr(old_mxcsr | flags);228  }229 230  ~ModifyMXCSR() { __builtin_ia32_ldmxcsr(old_mxcsr); }231 232private:233  unsigned old_mxcsr;234};235 236#endif237 238} // namespace testing239} // namespace LIBC_NAMESPACE_DECL240 241#define DECLARE_SPECIAL_CONSTANTS(T)                                           \242  using FPBits = LIBC_NAMESPACE::fputil::FPBits<T>;                            \243  using StorageType = typename FPBits::StorageType;                            \244                                                                               \245  static constexpr StorageType STORAGE_MAX =                                   \246      LIBC_NAMESPACE::cpp::numeric_limits<StorageType>::max();                 \247  const T zero = FPBits::zero(Sign::POS).get_val();                            \248  const T neg_zero = FPBits::zero(Sign::NEG).get_val();                        \249  const T aNaN = FPBits::quiet_nan(Sign::POS).get_val();                       \250  const T neg_aNaN = FPBits::quiet_nan(Sign::NEG).get_val();                   \251  const T sNaN = FPBits::signaling_nan(Sign::POS).get_val();                   \252  const T neg_sNaN = FPBits::signaling_nan(Sign::NEG).get_val();               \253  const T inf = FPBits::inf(Sign::POS).get_val();                              \254  const T neg_inf = FPBits::inf(Sign::NEG).get_val();                          \255  const T min_normal = FPBits::min_normal().get_val();                         \256  const T max_normal = FPBits::max_normal(Sign::POS).get_val();                \257  const T neg_max_normal = FPBits::max_normal(Sign::NEG).get_val();            \258  const T min_denormal = FPBits::min_subnormal(Sign::POS).get_val();           \259  const T neg_min_denormal = FPBits::min_subnormal(Sign::NEG).get_val();       \260  const T max_denormal = FPBits::max_subnormal().get_val();                    \261  static constexpr int UNKNOWN_MATH_ROUNDING_DIRECTION = 99;                   \262  static constexpr LIBC_NAMESPACE::cpp::array<int, 6>                          \263      MATH_ROUNDING_DIRECTIONS_INCLUDING_UNKNOWN = {                           \264          FP_INT_UPWARD,     FP_INT_DOWNWARD,                                  \265          FP_INT_TOWARDZERO, FP_INT_TONEARESTFROMZERO,                         \266          FP_INT_TONEAREST,  UNKNOWN_MATH_ROUNDING_DIRECTION,                  \267  };268 269#define EXPECT_FP_EQ(expected, actual)                                         \270  EXPECT_THAT(actual, LIBC_NAMESPACE::testing::getMatcher<                     \271                          LIBC_NAMESPACE::testing::TestCond::EQ>(expected))272 273#define EXPECT_CFP_EQ(expected, actual)                                        \274  EXPECT_THAT(actual, LIBC_NAMESPACE::testing::getMatcherComplex<              \275                          LIBC_NAMESPACE::testing::TestCond::EQ>(expected))276 277#define TEST_FP_EQ(expected, actual)                                           \278  LIBC_NAMESPACE::testing::getMatcher<LIBC_NAMESPACE::testing::TestCond::EQ>(  \279      expected)                                                                \280      .match(actual)281 282#define EXPECT_FP_IS_NAN(actual) EXPECT_TRUE((actual) != (actual))283 284#define ASSERT_FP_EQ(expected, actual)                                         \285  ASSERT_THAT(actual, LIBC_NAMESPACE::testing::getMatcher<                     \286                          LIBC_NAMESPACE::testing::TestCond::EQ>(expected))287 288#define EXPECT_FP_NE(expected, actual)                                         \289  EXPECT_THAT(actual, LIBC_NAMESPACE::testing::getMatcher<                     \290                          LIBC_NAMESPACE::testing::TestCond::NE>(expected))291 292#define ASSERT_FP_NE(expected, actual)                                         \293  ASSERT_THAT(actual, LIBC_NAMESPACE::testing::getMatcher<                     \294                          LIBC_NAMESPACE::testing::TestCond::NE>(expected))295 296#define EXPECT_MATH_ERRNO(expected)                                            \297  do {                                                                         \298    if ((LIBC_MATH & LIBC_MATH_NO_ERRNO) == 0)                                 \299      if (math_errhandling & MATH_ERRNO) {                                     \300        int actual = libc_errno;                                               \301        libc_errno = 0;                                                        \302        EXPECT_EQ(actual, expected);                                           \303      }                                                                        \304  } while (0)305 306#define ASSERT_MATH_ERRNO(expected)                                            \307  do {                                                                         \308    if ((LIBC_MATH & LIBC_MATH_NO_ERRNO) == 0)                                 \309      if (math_errhandling & MATH_ERRNO) {                                     \310        int actual = libc_errno;                                               \311        libc_errno = 0;                                                        \312        ASSERT_EQ(actual, expected);                                           \313      }                                                                        \314  } while (0)315 316#define EXPECT_FP_EXCEPTION(expected)                                          \317  do {                                                                         \318    if ((LIBC_MATH & LIBC_MATH_NO_EXCEPT) == 0)                                \319      if (math_errhandling & MATH_ERREXCEPT) {                                 \320        EXPECT_EQ(                                                             \321            LIBC_NAMESPACE::fputil::test_except(                               \322                static_cast<int>(FE_ALL_EXCEPT)) &                             \323                ((expected) ? (expected) : static_cast<int>(FE_ALL_EXCEPT)),   \324            (expected));                                                       \325      }                                                                        \326  } while (0)327 328#define ASSERT_FP_EXCEPTION(expected)                                          \329  do {                                                                         \330    if ((LIBC_MATH & LIBC_MATH_NO_EXCEPT) == 0)                                \331      if (math_errhandling & MATH_ERREXCEPT) {                                 \332        ASSERT_EQ(                                                             \333            LIBC_NAMESPACE::fputil::test_except(                               \334                static_cast<int>(FE_ALL_EXCEPT)) &                             \335                ((expected) ? (expected) : static_cast<int>(FE_ALL_EXCEPT)),   \336            (expected));                                                       \337      }                                                                        \338  } while (0)339 340#define EXPECT_FP_EQ_WITH_EXCEPTION(expected_val, actual_val, expected_except) \341  do {                                                                         \342    LIBC_NAMESPACE::fputil::clear_except(static_cast<int>(FE_ALL_EXCEPT));     \343    EXPECT_FP_EQ(expected_val, actual_val);                                    \344    EXPECT_FP_EXCEPTION(expected_except);                                      \345  } while (0)346 347#define EXPECT_FP_IS_NAN_WITH_EXCEPTION(actual_val, expected_except)           \348  do {                                                                         \349    LIBC_NAMESPACE::fputil::clear_except(static_cast<int>(FE_ALL_EXCEPT));     \350    EXPECT_FP_IS_NAN(actual_val);                                              \351    EXPECT_FP_EXCEPTION(expected_except);                                      \352  } while (0)353 354#define EXPECT_FP_EQ_ROUNDING_MODE(expected, actual, rounding_mode)            \355  do {                                                                         \356    using namespace LIBC_NAMESPACE::fputil::testing;                           \357    ForceRoundingMode __r((rounding_mode));                                    \358    if (__r.success) {                                                         \359      EXPECT_FP_EQ((expected), (actual));                                      \360    }                                                                          \361  } while (0)362 363#define EXPECT_FP_EQ_ROUNDING_NEAREST(expected, actual)                        \364  EXPECT_FP_EQ_ROUNDING_MODE((expected), (actual), RoundingMode::Nearest)365 366#define EXPECT_FP_EQ_ROUNDING_UPWARD(expected, actual)                         \367  EXPECT_FP_EQ_ROUNDING_MODE((expected), (actual), RoundingMode::Upward)368 369#define EXPECT_FP_EQ_ROUNDING_DOWNWARD(expected, actual)                       \370  EXPECT_FP_EQ_ROUNDING_MODE((expected), (actual), RoundingMode::Downward)371 372#define EXPECT_FP_EQ_ROUNDING_TOWARD_ZERO(expected, actual)                    \373  EXPECT_FP_EQ_ROUNDING_MODE((expected), (actual), RoundingMode::TowardZero)374 375#define EXPECT_FP_EQ_ALL_ROUNDING_1(expected, actual)                          \376  do {                                                                         \377    EXPECT_FP_EQ_ROUNDING_NEAREST((expected), (actual));                       \378    EXPECT_FP_EQ_ROUNDING_UPWARD((expected), (actual));                        \379    EXPECT_FP_EQ_ROUNDING_DOWNWARD((expected), (actual));                      \380    EXPECT_FP_EQ_ROUNDING_TOWARD_ZERO((expected), (actual));                   \381  } while (0)382 383#define EXPECT_FP_EQ_ALL_ROUNDING_4(expected_nearest, expected_upward,         \384                                    expected_downward, expected_toward_zero,   \385                                    actual)                                    \386  do {                                                                         \387    EXPECT_FP_EQ_ROUNDING_NEAREST((expected_nearest), (actual));               \388    EXPECT_FP_EQ_ROUNDING_UPWARD((expected_upward), (actual));                 \389    EXPECT_FP_EQ_ROUNDING_DOWNWARD((expected_downward), (actual));             \390    EXPECT_FP_EQ_ROUNDING_TOWARD_ZERO((expected_toward_zero), (actual));       \391  } while (0)392 393#define EXPECT_FP_EQ_ALL_ROUNDING_UNSUPPORTED(...)                             \394  static_assert(false, "Unsupported number of arguments")395 396#define EXPECT_FP_EQ_ALL_ROUNDING_GET_6TH_ARG(ARG1, ARG2, ARG3, ARG4, ARG5,    \397                                              ARG6, ...)                       \398  ARG6399 400#define EXPECT_FP_EQ_ALL_ROUNDING_SELECTION(...)                               \401  EXPECT_FP_EQ_ALL_ROUNDING_GET_6TH_ARG(                                       \402      __VA_ARGS__, EXPECT_FP_EQ_ALL_ROUNDING_4,                                \403      EXPECT_FP_EQ_ALL_ROUNDING_UNSUPPORTED,                                   \404      EXPECT_FP_EQ_ALL_ROUNDING_UNSUPPORTED, EXPECT_FP_EQ_ALL_ROUNDING_1)405 406#define EXPECT_FP_EQ_ALL_ROUNDING(...)                                         \407  EXPECT_FP_EQ_ALL_ROUNDING_SELECTION(__VA_ARGS__)(__VA_ARGS__)408 409#define ASSERT_FP_EQ_ROUNDING_MODE(expected, actual, rounding_mode)            \410  do {                                                                         \411    using namespace LIBC_NAMESPACE::fputil::testing;                           \412    ForceRoundingMode __r((rounding_mode));                                    \413    if (__r.success) {                                                         \414      ASSERT_FP_EQ((expected), (actual));                                      \415    }                                                                          \416  } while (0)417 418#define ASSERT_FP_EQ_ROUNDING_NEAREST(expected, actual)                        \419  ASSERT_FP_EQ_ROUNDING_MODE((expected), (actual), RoundingMode::Nearest)420 421#define ASSERT_FP_EQ_ROUNDING_UPWARD(expected, actual)                         \422  ASSERT_FP_EQ_ROUNDING_MODE((expected), (actual), RoundingMode::Upward)423 424#define ASSERT_FP_EQ_ROUNDING_DOWNWARD(expected, actual)                       \425  ASSERT_FP_EQ_ROUNDING_MODE((expected), (actual), RoundingMode::Downward)426 427#define ASSERT_FP_EQ_ROUNDING_TOWARD_ZERO(expected, actual)                    \428  ASSERT_FP_EQ_ROUNDING_MODE((expected), (actual), RoundingMode::TowardZero)429 430#define EXPECT_FP_EQ_WITH_EXCEPTION_ROUNDING_MODE(                             \431    expected, actual, expected_except, rounding_mode)                          \432  do {                                                                         \433    using namespace LIBC_NAMESPACE::fputil::testing;                           \434    ForceRoundingMode __r((rounding_mode));                                    \435    if (__r.success) {                                                         \436      LIBC_NAMESPACE::fputil::clear_except(static_cast<int>(FE_ALL_EXCEPT));   \437      EXPECT_FP_EQ((expected), (actual));                                      \438      EXPECT_FP_EXCEPTION(expected_except);                                    \439    }                                                                          \440  } while (0)441 442#define EXPECT_FP_EQ_WITH_EXCEPTION_ROUNDING_NEAREST(expected, actual,         \443                                                     expected_except)          \444  EXPECT_FP_EQ_WITH_EXCEPTION_ROUNDING_MODE(                                   \445      (expected), (actual), (expected_except), RoundingMode::Nearest)446 447#define EXPECT_FP_EQ_WITH_EXCEPTION_ROUNDING_UPWARD(expected, actual,          \448                                                    expected_except)           \449  EXPECT_FP_EQ_WITH_EXCEPTION_ROUNDING_MODE(                                   \450      (expected), (actual), (expected_except), RoundingMode::Upward)451 452#define EXPECT_FP_EQ_WITH_EXCEPTION_ROUNDING_DOWNWARD(expected, actual,        \453                                                      expected_except)         \454  EXPECT_FP_EQ_WITH_EXCEPTION_ROUNDING_MODE(                                   \455      (expected), (actual), (expected_except), RoundingMode::Downward)456 457#define EXPECT_FP_EQ_WITH_EXCEPTION_ROUNDING_TOWARD_ZERO(expected, actual,     \458                                                         expected_except)      \459  EXPECT_FP_EQ_WITH_EXCEPTION_ROUNDING_MODE(                                   \460      (expected), (actual), (expected_except), RoundingMode::TowardZero)461 462#define EXPECT_FP_EQ_WITH_EXCEPTION_ALL_ROUNDING(expected, actual,             \463                                                 expected_except)              \464  do {                                                                         \465    EXPECT_FP_EQ_WITH_EXCEPTION_ROUNDING_NEAREST((expected), (actual),         \466                                                 (expected_except));           \467    EXPECT_FP_EQ_WITH_EXCEPTION_ROUNDING_UPWARD((expected), (actual),          \468                                                (expected_except));            \469    EXPECT_FP_EQ_WITH_EXCEPTION_ROUNDING_DOWNWARD((expected), (actual),        \470                                                  (expected_except));          \471    EXPECT_FP_EQ_WITH_EXCEPTION_ROUNDING_TOWARD_ZERO((expected), (actual),     \472                                                     (expected_except));       \473  } while (0)474 475#endif // LLVM_LIBC_TEST_UNITTEST_FPMATCHER_H476