1//===-- Unittests for cos -------------------------------------------------===//
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 "src/__support/FPUtil/FPBits.h"
10#include "src/math/cos.h"
11#include "test/UnitTest/FPMatcher.h"
12#include "test/UnitTest/Test.h"
13#include "utils/MPFRWrapper/MPFRUtils.h"
14
15using LlvmLibcCosTest = LIBC_NAMESPACE::testing::FPTest<double>;
16
17namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
18
19using LIBC_NAMESPACE::testing::tlog;
20
21TEST_F(LlvmLibcCosTest, TrickyInputs) {
22 constexpr double INPUTS[] = {
23 0x1.8000000000009p-23, 0x1.8000000000024p-22,
24 0x1.800000000009p-21, 0x1.20000000000f3p-20,
25 0x1.800000000024p-20, 0x1.e0000000001c2p-20,
26 0x1.940c877fb7dacp-7, -0x1.f42fb19b5b9b2p-6,
27 -0x1.0285070f9f1bcp-5, 0x1.23f40dccdef72p+0,
28 0x1.43cf16358c9d7p+0, 0x1.addf3b9722265p+0,
29 0x1.ae78d360afa15p+0, 0x1.e31b55306f22cp+2,
30 0x1.e639103a05997p+2, -0x1.f7898d5a756ddp+2,
31 0x1.1685973506319p+3, 0x1.5f09cad750ab1p+3,
32 -0x1.aaf85537ea4c7p+3, 0x1.4f2b874135d27p+4,
33 0x1.13114266f9764p+4, 0x1.a211877de55dbp+4,
34 -0x1.a5eece87e8606p+4, 0x1.a65d441ea6dcep+4,
35 0x1.1ffb509f3db15p+5, 0x1.2345d1e090529p+5,
36 0x1.c96e28eb679f8p+5, 0x1.be886d9c2324dp+6,
37 -0x1.ab514bfc61c76p+7, -0x1.14823229799c2p+7,
38 0x1.48ff1782ca91dp+8, 0x1.dcbfda0c7559ep+8,
39 0x1.dcbfda0c7559ep+8, 0x1.2e566149bf5fdp+9,
40 0x1.cb996c60f437ep+9, 0x1.ae945054939c2p+10,
41 -0x1.119471e9216cdp+10, 0x1.ae945054939c2p+10,
42 0x1.fffffffffdb6p+24, 0x1.fd4da4ef37075p+29,
43 0x1.55202aefde314p+31, 0x1.b951f1572eba5p+31,
44 0x1.7776c2343ba4ep+101, 0x1.85fc0f04c0128p+101,
45 0x1.678309fa50d58p+110, 0x1.fffffffffef4ep+199,
46 0x1.3eec5912ea7cdp+331, -0x1.3eec5912ea7cdp+331,
47 -0x1.6deb37da81129p+205, 0x1.08087e9aad90bp+887,
48 -0x1.08087e9aad90bp+887, -0x1.8bb5847d49973p+845,
49 0x1.6ac5b262ca1ffp+849, 0x1.f08b14e1c4d0fp+890,
50 0x1.2b5fe88a9d8d5p+903, 0x1.f6d7518808571p+1023,
51 -0x1.a880417b7b119p+1023, 0x1.00a33764a0a83p-7,
52 0x1.fe81868fc47fep+1, 0x1.0da8cc189b47dp-10,
53 0x1.da1838053b866p+5, 0x1.ffffffffe854bp199,
54 };
55 constexpr int N = sizeof(INPUTS) / sizeof(INPUTS[0]);
56
57 for (int i = 0; i < N; ++i) {
58 double x = INPUTS[i];
59 ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Cos, x,
60 LIBC_NAMESPACE::cos(x), 0.5);
61 }
62}
63
64TEST_F(LlvmLibcCosTest, InDoubleRange) {
65 constexpr uint64_t COUNT = 1'234'51;
66 uint64_t START = LIBC_NAMESPACE::fputil::FPBits<double>(0x1.0p-50).uintval();
67 uint64_t STOP = LIBC_NAMESPACE::fputil::FPBits<double>(0x1.0p200).uintval();
68 uint64_t STEP = (STOP - START) / COUNT;
69
70 auto test = [&](mpfr::RoundingMode rounding_mode) {
71 mpfr::ForceRoundingMode __r(rounding_mode);
72 if (!__r.success)
73 return;
74
75 uint64_t fails = 0;
76 uint64_t tested = 0;
77 uint64_t total = 0;
78 double worst_input, worst_output = 0.0;
79 double ulp = 0.5;
80
81 for (uint64_t i = 0, v = START; i <= COUNT; ++i, v += STEP) {
82 double x = FPBits(v).get_val();
83 if (FPBits(v).is_nan() || FPBits(v).is_inf())
84 continue;
85
86 double result = LIBC_NAMESPACE::cos(x);
87 ++total;
88 if (FPBits(result).is_nan() || FPBits(result).is_inf())
89 continue;
90
91 ++tested;
92
93 if (!TEST_MPFR_MATCH_ROUNDING_SILENTLY(mpfr::Operation::Cos, x, result,
94 0.5, rounding_mode)) {
95 ++fails;
96 while (!TEST_MPFR_MATCH_ROUNDING_SILENTLY(mpfr::Operation::Cos, x,
97 result, ulp, rounding_mode)) {
98 worst_input = x;
99 worst_output = result;
100
101 if (ulp > 1000.0)
102 break;
103
104 ulp *= 2.0;
105 }
106 }
107 }
108 if (fails) {
109 tlog << " Cos failed: " << fails << "/" << tested << "/" << total
110 << " tests.\n";
111 tlog << " Max ULPs is at most: " << static_cast<uint64_t>(ulp) << ".\n";
112 EXPECT_MPFR_MATCH(mpfr::Operation::Cos, worst_input, worst_output, 0.5,
113 rounding_mode);
114 }
115 };
116
117 tlog << " Test Rounding To Nearest...\n";
118 test(mpfr::RoundingMode::Nearest);
119
120 tlog << " Test Rounding Downward...\n";
121 test(mpfr::RoundingMode::Downward);
122
123 tlog << " Test Rounding Upward...\n";
124 test(mpfr::RoundingMode::Upward);
125
126 tlog << " Test Rounding Toward Zero...\n";
127 test(mpfr::RoundingMode::TowardZero);
128}
129

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