1//===-- Utility class to test different flavors of ilogb --------*- 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_ILOGBTEST_H
10#define LLVM_LIBC_TEST_SRC_MATH_ILOGBTEST_H
11
12#include "src/__support/CPP/algorithm.h"
13#include "src/__support/FPUtil/FPBits.h"
14#include "src/__support/FPUtil/ManipulationFunctions.h"
15#include "test/UnitTest/FEnvSafeTest.h"
16#include "test/UnitTest/Test.h"
17
18using LIBC_NAMESPACE::Sign;
19
20template <typename OutType, typename InType>
21class LlvmLibcILogbTest : public LIBC_NAMESPACE::testing::FEnvSafeTest {
22 using FPBits = LIBC_NAMESPACE::fputil::FPBits<InType>;
23 using StorageType = typename FPBits::StorageType;
24
25public:
26 typedef OutType (*Func)(InType);
27
28 void test_special_numbers(Func func) {
29 EXPECT_EQ(LIBC_NAMESPACE::fputil::IntLogbConstants<OutType>::FP_LOGB0,
30 func(FPBits::zero(Sign::POS).get_val()));
31 EXPECT_EQ(LIBC_NAMESPACE::fputil::IntLogbConstants<OutType>::FP_LOGB0,
32 func(FPBits::zero(Sign::NEG).get_val()));
33 EXPECT_EQ(LIBC_NAMESPACE::fputil::IntLogbConstants<OutType>::FP_LOGBNAN,
34 func(FPBits::quiet_nan().get_val()));
35 EXPECT_EQ(LIBC_NAMESPACE::fputil::IntLogbConstants<OutType>::T_MAX,
36 func(FPBits::inf(Sign::POS).get_val()));
37 EXPECT_EQ(LIBC_NAMESPACE::fputil::IntLogbConstants<OutType>::T_MAX,
38 func(FPBits::inf(Sign::NEG).get_val()));
39 }
40
41 void test_powers_of_two(Func func) {
42 EXPECT_EQ(OutType(0), func(InType(1.0)));
43 EXPECT_EQ(OutType(0), func(InType(-1.0)));
44
45 EXPECT_EQ(OutType(1), func(InType(2.0)));
46 EXPECT_EQ(OutType(1), func(InType(-2.0)));
47
48 EXPECT_EQ(OutType(2), func(InType(4.0)));
49 EXPECT_EQ(OutType(2), func(InType(-4.0)));
50
51 EXPECT_EQ(OutType(3), func(InType(8.0)));
52 EXPECT_EQ(OutType(3), func(InType(-8.0)));
53
54 EXPECT_EQ(OutType(4), func(InType(16.0)));
55 EXPECT_EQ(OutType(4), func(InType(-16.0)));
56
57 EXPECT_EQ(OutType(5), func(InType(32.0)));
58 EXPECT_EQ(OutType(5), func(InType(-32.0)));
59 }
60
61 void test_some_integers(Func func) {
62 EXPECT_EQ(OutType(1), func(InType(3.0)));
63 EXPECT_EQ(OutType(1), func(InType(-3.0)));
64
65 EXPECT_EQ(OutType(2), func(InType(7.0)));
66 EXPECT_EQ(OutType(2), func(InType(-7.0)));
67
68 EXPECT_EQ(OutType(3), func(InType(10.0)));
69 EXPECT_EQ(OutType(3), func(InType(-10.0)));
70
71 EXPECT_EQ(OutType(4), func(InType(31.0)));
72 EXPECT_EQ(OutType(4), func(InType(-31.0)));
73
74 EXPECT_EQ(OutType(5), func(InType(55.0)));
75 EXPECT_EQ(OutType(5), func(InType(-55.0)));
76 }
77
78 void test_subnormal_range(Func func) {
79 constexpr StorageType MIN_SUBNORMAL = FPBits::min_subnormal().uintval();
80 constexpr StorageType MAX_SUBNORMAL = FPBits::max_subnormal().uintval();
81 constexpr int COUNT = 10'001;
82 constexpr StorageType STEP = LIBC_NAMESPACE::cpp::max(
83 static_cast<StorageType>((MAX_SUBNORMAL - MIN_SUBNORMAL) / COUNT),
84 StorageType(1));
85 for (StorageType v = MIN_SUBNORMAL; v <= MAX_SUBNORMAL; v += STEP) {
86 FPBits x_bits(v);
87 if (x_bits.is_zero() || x_bits.is_inf_or_nan())
88 continue;
89
90 InType x = x_bits.get_val();
91
92 int exponent;
93 LIBC_NAMESPACE::fputil::frexp(x, exponent);
94 ASSERT_EQ(static_cast<OutType>(exponent), func(x) + OutType(1));
95 }
96 }
97
98 void test_normal_range(Func func) {
99 constexpr StorageType MIN_NORMAL = FPBits::min_normal().uintval();
100 constexpr StorageType MAX_NORMAL = FPBits::max_normal().uintval();
101 constexpr int COUNT = 10'001;
102 constexpr StorageType STEP = LIBC_NAMESPACE::cpp::max(
103 static_cast<StorageType>((MAX_NORMAL - MIN_NORMAL) / COUNT),
104 StorageType(1));
105 for (StorageType v = MIN_NORMAL; v <= MAX_NORMAL; v += STEP) {
106 FPBits x_bits(v);
107 if (x_bits.is_zero() || x_bits.is_inf_or_nan())
108 continue;
109
110 InType x = x_bits.get_val();
111
112 int exponent;
113 LIBC_NAMESPACE::fputil::frexp(x, exponent);
114 ASSERT_EQ(static_cast<OutType>(exponent), func(x) + OutType(1));
115 }
116 }
117};
118
119#define LIST_INTLOGB_TESTS(OutType, InType, Func) \
120 using LlvmLibcIntLogbTest = LlvmLibcILogbTest<OutType, InType>; \
121 TEST_F(LlvmLibcIntLogbTest, SpecialNumbers) { test_special_numbers(&Func); } \
122 TEST_F(LlvmLibcIntLogbTest, PowersOfTwo) { test_powers_of_two(&Func); } \
123 TEST_F(LlvmLibcIntLogbTest, SomeIntegers) { test_some_integers(&Func); } \
124 TEST_F(LlvmLibcIntLogbTest, SubnormalRange) { test_subnormal_range(&Func); } \
125 TEST_F(LlvmLibcIntLogbTest, NormalRange) { test_normal_range(&Func); } \
126 static_assert(true)
127
128#endif // LLVM_LIBC_TEST_SRC_MATH_ILOGBTEST_H
129

source code of libc/test/src/math/smoke/ILogbTest.h