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