1//===-- Unittests for 10^x ------------------------------------------------===//
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/exp10.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 LlvmLibcExp10Test = LIBC_NAMESPACE::testing::FPTest<double>;
21
22namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
23using LIBC_NAMESPACE::testing::tlog;
24
25TEST_F(LlvmLibcExp10Test, SpecialNumbers) {
26 EXPECT_FP_EQ(aNaN, LIBC_NAMESPACE::exp10(aNaN));
27 EXPECT_FP_EQ(inf, LIBC_NAMESPACE::exp10(inf));
28 EXPECT_FP_EQ_ALL_ROUNDING(zero, LIBC_NAMESPACE::exp10(neg_inf));
29 EXPECT_FP_EQ_WITH_EXCEPTION(zero, LIBC_NAMESPACE::exp10(-0x1.0p20),
30 FE_UNDERFLOW);
31 EXPECT_FP_EQ_WITH_EXCEPTION(inf, LIBC_NAMESPACE::exp10(0x1.0p20),
32 FE_OVERFLOW);
33 EXPECT_FP_EQ_ALL_ROUNDING(1.0, LIBC_NAMESPACE::exp10(0.0));
34 EXPECT_FP_EQ_ALL_ROUNDING(1.0, LIBC_NAMESPACE::exp10(-0.0));
35}
36
37TEST_F(LlvmLibcExp10Test, TrickyInputs) {
38 constexpr int N = 41;
39 constexpr uint64_t INPUTS[N] = {
40 0x40033093317082F8, 0x3FD79289C6E6A5C0,
41 0x3FD05DE80A173EA0, // 0x1.05de80a173eap-2
42 0xbf1eb7a4cb841fcc, // -0x1.eb7a4cb841fccp-14
43 0xbf19a61fb925970d,
44 0x3fda7b764e2cf47a, // 0x1.a7b764e2cf47ap-2
45 0xc04757852a4b93aa, // -0x1.757852a4b93aap+5
46 0x4044c19e5712e377, // x=0x1.4c19e5712e377p+5
47 0xbf19a61fb925970d, // x=-0x1.9a61fb925970dp-14
48 0xc039a74cdab36c28, // x=-0x1.9a74cdab36c28p+4
49 0xc085b3e4e2e3bba9, // x=-0x1.5b3e4e2e3bba9p+9
50 0xc086960d591aec34, // x=-0x1.6960d591aec34p+9
51 0xc086232c09d58d91, // x=-0x1.6232c09d58d91p+9
52 0xc0874910d52d3051, // x=-0x1.74910d52d3051p9
53 0xc0867a172ceb0990, // x=-0x1.67a172ceb099p+9
54 0xc08ff80000000000, // x=-0x1.ff8p+9
55 0xbc971547652b82fe, // x=-0x1.71547652b82fep-54
56 0x0000000000000000, // x = 0
57 0x3ff0000000000000, // x = 1
58 0x4000000000000000, // x = 2
59 0x4008000000000000, // x = 3
60 0x4010000000000000, // x = 4
61 0x4014000000000000, // x = 5
62 0x4018000000000000, // x = 6
63 0x401c000000000000, // x = 7
64 0x4020000000000000, // x = 8
65 0x4022000000000000, // x = 9
66 0x4024000000000000, // x = 10
67 0x4026000000000000, // x = 11
68 0x4028000000000000, // x = 12
69 0x402a000000000000, // x = 13
70 0x402c000000000000, // x = 14
71 0x402e000000000000, // x = 15
72 0x4030000000000000, // x = 16
73 0x4031000000000000, // x = 17
74 0x4032000000000000, // x = 18
75 0x4033000000000000, // x = 19
76 0x4034000000000000, // x = 20
77 0x4035000000000000, // x = 21
78 0x4036000000000000, // x = 22
79 0x4037000000000000, // x = 23
80 };
81 for (int i = 0; i < N; ++i) {
82 double x = FPBits(INPUTS[i]).get_val();
83 EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp10, x,
84 LIBC_NAMESPACE::exp10(x), 0.5);
85 }
86}
87
88TEST_F(LlvmLibcExp10Test, InDoubleRange) {
89 constexpr uint64_t COUNT = 1'231;
90 uint64_t START = LIBC_NAMESPACE::fputil::FPBits<double>(0.25).uintval();
91 uint64_t STOP = LIBC_NAMESPACE::fputil::FPBits<double>(4.0).uintval();
92 uint64_t STEP = (STOP - START) / COUNT;
93
94 auto test = [&](mpfr::RoundingMode rounding_mode) {
95 mpfr::ForceRoundingMode __r(rounding_mode);
96 if (!__r.success)
97 return;
98
99 uint64_t fails = 0;
100 uint64_t count = 0;
101 uint64_t cc = 0;
102 double mx, mr = 0.0;
103 double tol = 0.5;
104
105 for (uint64_t i = 0, v = START; i <= COUNT; ++i, v += STEP) {
106 double x = FPBits(v).get_val();
107 if (isnan(x: x) || isinf(x: x) || x < 0.0)
108 continue;
109 LIBC_NAMESPACE::libc_errno = 0;
110 double result = LIBC_NAMESPACE::exp10(x);
111 ++cc;
112 if (isnan(x: result) || isinf(x: result))
113 continue;
114
115 ++count;
116
117 if (!TEST_MPFR_MATCH_ROUNDING_SILENTLY(mpfr::Operation::Exp10, x, result,
118 0.5, rounding_mode)) {
119 ++fails;
120 while (!TEST_MPFR_MATCH_ROUNDING_SILENTLY(mpfr::Operation::Exp10, x,
121 result, tol, rounding_mode)) {
122 mx = x;
123 mr = result;
124
125 if (tol > 1000.0)
126 break;
127
128 tol *= 2.0;
129 }
130 }
131 }
132 tlog << " Exp10 failed: " << fails << "/" << count << "/" << cc
133 << " tests.\n";
134 tlog << " Max ULPs is at most: " << static_cast<uint64_t>(tol) << ".\n";
135 if (fails) {
136 EXPECT_MPFR_MATCH(mpfr::Operation::Exp10, mx, mr, 0.5, rounding_mode);
137 }
138 };
139
140 tlog << " Test Rounding To Nearest...\n";
141 test(mpfr::RoundingMode::Nearest);
142
143 tlog << " Test Rounding Downward...\n";
144 test(mpfr::RoundingMode::Downward);
145
146 tlog << " Test Rounding Upward...\n";
147 test(mpfr::RoundingMode::Upward);
148
149 tlog << " Test Rounding Toward Zero...\n";
150 test(mpfr::RoundingMode::TowardZero);
151}
152

source code of libc/test/src/math/exp10_test.cpp