xref: /aosp_15_r20/external/llvm-libc/test/src/math/atan2f_test.cpp (revision 71db0c75aadcf003ffe3238005f61d7618a3fead)
1 //===-- Unittests for atan2f ----------------------------------------------===//
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/math/atan2f.h"
12 #include "test/UnitTest/FPMatcher.h"
13 #include "test/UnitTest/Test.h"
14 #include "utils/MPFRWrapper/MPFRUtils.h"
15 
16 using LlvmLibcAtan2fTest = LIBC_NAMESPACE::testing::FPTest<float>;
17 using LIBC_NAMESPACE::testing::tlog;
18 
19 namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
20 
TEST_F(LlvmLibcAtan2fTest,TrickyInputs)21 TEST_F(LlvmLibcAtan2fTest, TrickyInputs) {
22   constexpr int N = 17;
23   mpfr::BinaryInput<float> INPUTS[N] = {
24       {0x1.0cb3a4p+20f, 0x1.4ebacp+22f},   {0x1.12215p+1f, 0x1.4fabfcp+22f},
25       {-0x1.13baaep+41f, 0x1.5bd22ep+23f}, {0x1.1ff7dcp+41f, 0x1.aec0a6p+23f},
26       {0x1.2bc794p+23f, 0x1.0bc0c6p+23f},  {0x1.2fba3ap+42f, 0x1.f99456p+23f},
27       {0x1.5ea1f8p+27f, 0x1.f2a1aep+23f},  {0x1.7a931p+44f, 0x1.352ac4p+22f},
28       {0x1.8802bcp+21f, 0x1.8f130ap+23f},  {0x1.658ef8p+17f, 0x1.3c00f4p+22f},
29       {0x1.69fb0cp+21f, 0x1.39e4c4p+23f},  {0x1.8eb24cp+11f, 0x1.36518p+23f},
30       {0x1.9e7ebp+30f, 0x1.d80522p+23f},   {0x1.b4bdeep+19f, 0x1.c19b4p+23f},
31       {0x1.bc201p+43f, 0x1.617346p+23f},   {0x1.c96c3cp+20f, 0x1.c01d1ep+23f},
32       {0x1.781fcp+28f, 0x1.dcb3cap+23f},
33   };
34 
35   for (int i = 0; i < N; ++i) {
36     float x = INPUTS[i].x;
37     float y = INPUTS[i].y;
38     ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Atan2, INPUTS[i],
39                                    LIBC_NAMESPACE::atan2f(x, y), 0.5);
40     INPUTS[i].x = -INPUTS[i].x;
41     ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Atan2, INPUTS[i],
42                                    LIBC_NAMESPACE::atan2f(-x, y), 0.5);
43     INPUTS[i].y = -INPUTS[i].y;
44     ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Atan2, INPUTS[i],
45                                    LIBC_NAMESPACE::atan2f(-x, -y), 0.5);
46     INPUTS[i].x = -INPUTS[i].x;
47     ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Atan2, INPUTS[i],
48                                    LIBC_NAMESPACE::atan2f(x, -y), 0.5);
49   }
50 }
51 
TEST_F(LlvmLibcAtan2fTest,InFloatRange)52 TEST_F(LlvmLibcAtan2fTest, InFloatRange) {
53   constexpr uint32_t X_COUNT = 1'23;
54   constexpr uint32_t X_START = FPBits(0.25f).uintval();
55   constexpr uint32_t X_STOP = FPBits(4.0f).uintval();
56   constexpr uint32_t X_STEP = (X_STOP - X_START) / X_COUNT;
57 
58   constexpr uint32_t Y_COUNT = 1'37;
59   constexpr uint32_t Y_START = FPBits(0.25f).uintval();
60   constexpr uint32_t Y_STOP = FPBits(4.0f).uintval();
61   constexpr uint32_t Y_STEP = (Y_STOP - Y_START) / Y_COUNT;
62 
63   auto test = [&](mpfr::RoundingMode rounding_mode) {
64     mpfr::ForceRoundingMode __r(rounding_mode);
65     if (!__r.success)
66       return;
67 
68     uint64_t fails = 0;
69     uint64_t finite_count = 0;
70     uint64_t total_count = 0;
71     float failed_x, failed_y, failed_r = 0.0;
72     double tol = 0.5;
73 
74     for (uint32_t i = 0, v = X_START; i <= X_COUNT; ++i, v += X_STEP) {
75       float x = FPBits(v).get_val();
76       if (FPBits(v).is_nan() || FPBits(v).is_inf() || x < 0.0)
77         continue;
78 
79       for (uint32_t j = 0, w = Y_START; j <= Y_COUNT; ++j, w += Y_STEP) {
80         float y = FPBits(w).get_val();
81         if (FPBits(w).is_nan() || FPBits(w).is_inf())
82           continue;
83 
84         LIBC_NAMESPACE::libc_errno = 0;
85         float result = LIBC_NAMESPACE::atan2f(x, y);
86         ++total_count;
87         if (FPBits(result).is_nan() || FPBits(result).is_inf())
88           continue;
89 
90         ++finite_count;
91         mpfr::BinaryInput<float> inputs{x, y};
92 
93         if (!TEST_MPFR_MATCH_ROUNDING_SILENTLY(mpfr::Operation::Atan2, inputs,
94                                                result, 0.5, rounding_mode)) {
95           ++fails;
96           while (!TEST_MPFR_MATCH_ROUNDING_SILENTLY(
97               mpfr::Operation::Atan2, inputs, result, tol, rounding_mode)) {
98             failed_x = x;
99             failed_y = y;
100             failed_r = result;
101 
102             if (tol > 1000.0)
103               break;
104 
105             tol *= 2.0;
106           }
107         }
108       }
109     }
110     if (fails || (finite_count < total_count)) {
111       tlog << " Atan2f failed: " << fails << "/" << finite_count << "/"
112            << total_count << " tests.\n"
113            << "   Max ULPs is at most: " << static_cast<uint64_t>(tol) << ".\n";
114     }
115     if (fails) {
116       mpfr::BinaryInput<float> inputs{failed_x, failed_y};
117       EXPECT_MPFR_MATCH(mpfr::Operation::Atan2, inputs, failed_r, 0.5,
118                         rounding_mode);
119     }
120   };
121 
122   tlog << " Test Rounding To Nearest...\n";
123   test(mpfr::RoundingMode::Nearest);
124 
125   tlog << " Test Rounding Downward...\n";
126   test(mpfr::RoundingMode::Downward);
127 
128   tlog << " Test Rounding Upward...\n";
129   test(mpfr::RoundingMode::Upward);
130 
131   tlog << " Test Rounding Toward Zero...\n";
132   test(mpfr::RoundingMode::TowardZero);
133 }
134