1//===-- Unittests for log10 -----------------------------------------------===//
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#include "hdr/math_macros.h"
10#include "src/__support/FPUtil/FPBits.h"
11#include "src/errno/libc_errno.h"
12#include "src/math/log10.h"
13#include "test/UnitTest/FPMatcher.h"
14#include "test/UnitTest/Test.h"
15#include "utils/MPFRWrapper/MPFRUtils.h"
16
17#include <errno.h>
18#include <stdint.h>
19
20using LlvmLibcLog10Test = LIBC_NAMESPACE::testing::FPTest<double>;
21
22namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
23using LIBC_NAMESPACE::testing::tlog;
24
25TEST_F(LlvmLibcLog10Test, SpecialNumbers) {
26 EXPECT_FP_EQ(aNaN, LIBC_NAMESPACE::log10(aNaN));
27 EXPECT_FP_EQ(inf, LIBC_NAMESPACE::log10(inf));
28 EXPECT_FP_IS_NAN_WITH_EXCEPTION(LIBC_NAMESPACE::log10(neg_inf), FE_INVALID);
29 EXPECT_FP_EQ_WITH_EXCEPTION(neg_inf, LIBC_NAMESPACE::log10(0.0),
30 FE_DIVBYZERO);
31 EXPECT_FP_EQ_WITH_EXCEPTION(neg_inf, LIBC_NAMESPACE::log10(-0.0),
32 FE_DIVBYZERO);
33 EXPECT_FP_IS_NAN_WITH_EXCEPTION(LIBC_NAMESPACE::log10(-1.0), FE_INVALID);
34 EXPECT_FP_EQ_ALL_ROUNDING(zero, LIBC_NAMESPACE::log10(1.0));
35}
36
37TEST_F(LlvmLibcLog10Test, TrickyInputs) {
38 constexpr int N = 36;
39 constexpr uint64_t INPUTS[N] = {
40 0x3ff0000000000000, // x = 1.0
41 0x4024000000000000, // x = 10.0
42 0x4059000000000000, // x = 10^2
43 0x408f400000000000, // x = 10^3
44 0x40c3880000000000, // x = 10^4
45 0x40f86a0000000000, // x = 10^5
46 0x412e848000000000, // x = 10^6
47 0x416312d000000000, // x = 10^7
48 0x4197d78400000000, // x = 10^8
49 0x41cdcd6500000000, // x = 10^9
50 0x4202a05f20000000, // x = 10^10
51 0x42374876e8000000, // x = 10^11
52 0x426d1a94a2000000, // x = 10^12
53 0x42a2309ce5400000, // x = 10^13
54 0x42d6bcc41e900000, // x = 10^14
55 0x430c6bf526340000, // x = 10^15
56 0x4341c37937e08000, // x = 10^16
57 0x4376345785d8a000, // x = 10^17
58 0x43abc16d674ec800, // x = 10^18
59 0x43e158e460913d00, // x = 10^19
60 0x4415af1d78b58c40, // x = 10^20
61 0x444b1ae4d6e2ef50, // x = 10^21
62 0x4480f0cf064dd592, // x = 10^22
63 0x3fefffffffef06ad, 0x3fefde0f22c7d0eb, 0x225e7812faadb32f,
64 0x3fee1076964c2903, 0x3fdfe93fff7fceb0, 0x3ff012631ad8df10,
65 0x3fefbfdaa448ed98, 0x44b0c9705a25ce02, 0x2c88d301065c7f9b,
66 0x30160580e7268a99, 0x5ca04103b7eaa345, 0x19ad77dc4a40093f,
67 0x0000449fb5c8a96e};
68 for (int i = 0; i < N; ++i) {
69 double x = FPBits(INPUTS[i]).get_val();
70 EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Log10, x,
71 LIBC_NAMESPACE::log10(x), 0.5);
72 }
73}
74
75TEST_F(LlvmLibcLog10Test, AllExponents) {
76 double x = 0x1.0p-1074;
77 for (int i = -1074; i < 1024; ++i, x *= 2.0) {
78 ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Log10, x,
79 LIBC_NAMESPACE::log10(x), 0.5);
80 }
81}
82
83TEST_F(LlvmLibcLog10Test, InDoubleRange) {
84 constexpr uint64_t COUNT = 1'001;
85 constexpr uint64_t START = 0x3FD0'0000'0000'0000ULL; // 0.25
86 constexpr uint64_t STOP = 0x4010'0000'0000'0000ULL; // 4.0
87 // constexpr uint64_t START = 0x3FF0'0000'0000'0000ULL; // 1.0
88 // constexpr uint64_t STOP = 0x4000'0000'0000'0000ULL; // 2.0
89 constexpr uint64_t STEP = (STOP - START) / COUNT;
90
91 auto test = [&](mpfr::RoundingMode rounding_mode) {
92 mpfr::ForceRoundingMode __r(rounding_mode);
93 if (!__r.success)
94 return;
95 uint64_t fails = 0;
96 uint64_t count = 0;
97 uint64_t cc = 0;
98 double mx, mr = 0.0;
99 double tol = 0.5;
100
101 for (uint64_t i = 0, v = START; i <= COUNT; ++i, v += STEP) {
102 double x = FPBits(v).get_val();
103 if (isnan(x: x) || isinf(x: x) || x < 0.0)
104 continue;
105 LIBC_NAMESPACE::libc_errno = 0;
106 double result = LIBC_NAMESPACE::log10(x);
107 ++cc;
108 if (isnan(x: result) || isinf(x: result))
109 continue;
110
111 ++count;
112 // ASSERT_MPFR_MATCH(mpfr::Operation::Log10, x, result, 0.5);
113 if (!TEST_MPFR_MATCH_ROUNDING_SILENTLY(mpfr::Operation::Log10, x, result,
114 0.5, rounding_mode)) {
115 ++fails;
116 while (!TEST_MPFR_MATCH_ROUNDING_SILENTLY(mpfr::Operation::Log10, x,
117 result, tol, rounding_mode)) {
118 mx = x;
119 mr = result;
120 tol *= 2.0;
121 }
122 }
123 }
124 tlog << " Log10 failed: " << fails << "/" << count << "/" << cc
125 << " tests.\n";
126 tlog << " Max ULPs is at most: " << static_cast<uint64_t>(tol) << ".\n";
127 if (fails) {
128 EXPECT_MPFR_MATCH(mpfr::Operation::Log10, mx, mr, 0.5, rounding_mode);
129 }
130 };
131
132 tlog << " Test Rounding To Nearest...\n";
133 test(mpfr::RoundingMode::Nearest);
134
135 tlog << " Test Rounding Downward...\n";
136 test(mpfr::RoundingMode::Downward);
137
138 tlog << " Test Rounding Upward...\n";
139 test(mpfr::RoundingMode::Upward);
140
141 tlog << " Test Rounding Toward Zero...\n";
142 test(mpfr::RoundingMode::TowardZero);
143}
144

source code of libc/test/src/math/log10_test.cpp