1 //===-- Utility class to test different flavors of rint ---------*- 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-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef LLVM_LIBC_TEST_SRC_MATH_RINTTEST_H 10 #define LLVM_LIBC_TEST_SRC_MATH_RINTTEST_H 11 12 #include "src/__support/CPP/algorithm.h" 13 #include "src/__support/FPUtil/FEnvImpl.h" 14 #include "src/__support/FPUtil/FPBits.h" 15 #include "test/UnitTest/FEnvSafeTest.h" 16 #include "test/UnitTest/FPMatcher.h" 17 #include "test/UnitTest/Test.h" 18 #include "utils/MPFRWrapper/MPFRUtils.h" 19 20 #include "hdr/fenv_macros.h" 21 #include "hdr/math_macros.h" 22 23 namespace mpfr = LIBC_NAMESPACE::testing::mpfr; 24 using LIBC_NAMESPACE::Sign; 25 26 static constexpr int ROUNDING_MODES[4] = {FE_UPWARD, FE_DOWNWARD, FE_TOWARDZERO, 27 FE_TONEAREST}; 28 29 template <typename T> 30 class RIntTestTemplate : public LIBC_NAMESPACE::testing::FEnvSafeTest { 31 public: 32 typedef T (*RIntFunc)(T); 33 34 private: 35 using FPBits = LIBC_NAMESPACE::fputil::FPBits<T>; 36 using StorageType = typename FPBits::StorageType; 37 38 const T inf = FPBits::inf(Sign::POS).get_val(); 39 const T neg_inf = FPBits::inf(Sign::NEG).get_val(); 40 const T zero = FPBits::zero(Sign::POS).get_val(); 41 const T neg_zero = FPBits::zero(Sign::NEG).get_val(); 42 const T nan = FPBits::quiet_nan().get_val(); 43 44 static constexpr StorageType MIN_SUBNORMAL = 45 FPBits::min_subnormal().uintval(); 46 static constexpr StorageType MAX_SUBNORMAL = 47 FPBits::max_subnormal().uintval(); 48 static constexpr StorageType MIN_NORMAL = FPBits::min_normal().uintval(); 49 static constexpr StorageType MAX_NORMAL = FPBits::max_normal().uintval(); 50 to_mpfr_rounding_mode(int mode)51 static inline mpfr::RoundingMode to_mpfr_rounding_mode(int mode) { 52 switch (mode) { 53 case FE_UPWARD: 54 return mpfr::RoundingMode::Upward; 55 case FE_DOWNWARD: 56 return mpfr::RoundingMode::Downward; 57 case FE_TOWARDZERO: 58 return mpfr::RoundingMode::TowardZero; 59 case FE_TONEAREST: 60 return mpfr::RoundingMode::Nearest; 61 default: 62 __builtin_unreachable(); 63 } 64 } 65 66 public: testSpecialNumbers(RIntFunc func)67 void testSpecialNumbers(RIntFunc func) { 68 for (int mode : ROUNDING_MODES) { 69 LIBC_NAMESPACE::fputil::set_round(mode); 70 ASSERT_FP_EQ(inf, func(inf)); 71 ASSERT_FP_EQ(neg_inf, func(neg_inf)); 72 ASSERT_FP_EQ(nan, func(nan)); 73 ASSERT_FP_EQ(zero, func(zero)); 74 ASSERT_FP_EQ(neg_zero, func(neg_zero)); 75 } 76 } 77 testRoundNumbers(RIntFunc func)78 void testRoundNumbers(RIntFunc func) { 79 for (int mode : ROUNDING_MODES) { 80 LIBC_NAMESPACE::fputil::set_round(mode); 81 mpfr::RoundingMode mpfr_mode = to_mpfr_rounding_mode(mode); 82 ASSERT_FP_EQ(func(T(1.0)), mpfr::round(T(1.0), mpfr_mode)); 83 ASSERT_FP_EQ(func(T(-1.0)), mpfr::round(T(-1.0), mpfr_mode)); 84 ASSERT_FP_EQ(func(T(10.0)), mpfr::round(T(10.0), mpfr_mode)); 85 ASSERT_FP_EQ(func(T(-10.0)), mpfr::round(T(-10.0), mpfr_mode)); 86 ASSERT_FP_EQ(func(T(1234.0)), mpfr::round(T(1234.0), mpfr_mode)); 87 ASSERT_FP_EQ(func(T(-1234.0)), mpfr::round(T(-1234.0), mpfr_mode)); 88 } 89 } 90 testFractions(RIntFunc func)91 void testFractions(RIntFunc func) { 92 for (int mode : ROUNDING_MODES) { 93 LIBC_NAMESPACE::fputil::set_round(mode); 94 mpfr::RoundingMode mpfr_mode = to_mpfr_rounding_mode(mode); 95 ASSERT_FP_EQ(func(T(0.5)), mpfr::round(T(0.5), mpfr_mode)); 96 ASSERT_FP_EQ(func(T(-0.5)), mpfr::round(T(-0.5), mpfr_mode)); 97 ASSERT_FP_EQ(func(T(0.115)), mpfr::round(T(0.115), mpfr_mode)); 98 ASSERT_FP_EQ(func(T(-0.115)), mpfr::round(T(-0.115), mpfr_mode)); 99 ASSERT_FP_EQ(func(T(0.715)), mpfr::round(T(0.715), mpfr_mode)); 100 ASSERT_FP_EQ(func(T(-0.715)), mpfr::round(T(-0.715), mpfr_mode)); 101 } 102 } 103 testSubnormalRange(RIntFunc func)104 void testSubnormalRange(RIntFunc func) { 105 constexpr int COUNT = 100'001; 106 constexpr StorageType STEP = LIBC_NAMESPACE::cpp::max( 107 static_cast<StorageType>((MAX_SUBNORMAL - MIN_SUBNORMAL) / COUNT), 108 StorageType(1)); 109 for (StorageType i = MIN_SUBNORMAL; i <= MAX_SUBNORMAL; i += STEP) { 110 T x = FPBits(i).get_val(); 111 for (int mode : ROUNDING_MODES) { 112 LIBC_NAMESPACE::fputil::set_round(mode); 113 mpfr::RoundingMode mpfr_mode = to_mpfr_rounding_mode(mode); 114 ASSERT_FP_EQ(func(x), mpfr::round(x, mpfr_mode)); 115 } 116 } 117 } 118 119 void testNormalRange(RIntFunc func) { 120 constexpr int COUNT = 100'001; 121 constexpr StorageType STEP = LIBC_NAMESPACE::cpp::max( 122 static_cast<StorageType>((MAX_NORMAL - MIN_NORMAL) / COUNT), 123 StorageType(1)); 124 for (StorageType i = MIN_NORMAL; i <= MAX_NORMAL; i += STEP) { 125 FPBits xbits(i); 126 T x = xbits.get_val(); 127 // In normal range on x86 platforms, the long double implicit 1 bit can be 128 // zero making the numbers NaN. We will skip them. 129 if (xbits.is_nan()) 130 continue; 131 132 for (int mode : ROUNDING_MODES) { 133 LIBC_NAMESPACE::fputil::set_round(mode); 134 mpfr::RoundingMode mpfr_mode = to_mpfr_rounding_mode(mode); 135 ASSERT_FP_EQ(func(x), mpfr::round(x, mpfr_mode)); 136 } 137 } 138 } 139 }; 140 141 #define LIST_RINT_TESTS(F, func) \ 142 using LlvmLibcRIntTest = RIntTestTemplate<F>; \ 143 TEST_F(LlvmLibcRIntTest, specialNumbers) { testSpecialNumbers(&func); } \ 144 TEST_F(LlvmLibcRIntTest, RoundNumbers) { testRoundNumbers(&func); } \ 145 TEST_F(LlvmLibcRIntTest, Fractions) { testFractions(&func); } \ 146 TEST_F(LlvmLibcRIntTest, SubnormalRange) { testSubnormalRange(&func); } \ 147 TEST_F(LlvmLibcRIntTest, NormalRange) { testNormalRange(&func); } 148 149 #endif // LLVM_LIBC_TEST_SRC_MATH_RINTTEST_H 150