xref: /aosp_15_r20/external/llvm-libc/test/src/math/powf_test.cpp (revision 71db0c75aadcf003ffe3238005f61d7618a3fead)
1 //===-- Unittests for powf ------------------------------------------------===//
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/powf.h"
12 #include "test/UnitTest/FPMatcher.h"
13 #include "test/UnitTest/Test.h"
14 #include "utils/MPFRWrapper/MPFRUtils.h"
15 
16 #include <stdint.h>
17 
18 using LlvmLibcPowfTest = LIBC_NAMESPACE::testing::FPTest<float>;
19 using LIBC_NAMESPACE::testing::tlog;
20 
21 namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
22 
TEST_F(LlvmLibcPowfTest,TrickyInputs)23 TEST_F(LlvmLibcPowfTest, TrickyInputs) {
24   constexpr int N = 13;
25   constexpr mpfr::BinaryInput<float> INPUTS[N] = {
26       {0x1.290bbp-124f, 0x1.1e6d92p-25f},
27       {0x1.2e9fb6p+5f, -0x1.1b82b6p-18f},
28       {0x1.6877f6p+60f, -0x1.75f1c6p-4f},
29       {0x1.0936acp-63f, -0x1.55200ep-15f},
30       {0x1.d6d72ap+43f, -0x1.749ccap-5f},
31       {0x1.4afb2ap-40f, 0x1.063198p+0f},
32       {0x1.0124dep+0f, -0x1.fdb016p+9f},
33       {0x1.1058p+0f, 0x1.ap+64f},
34       {0x1.1058p+0f, -0x1.ap+64f},
35       {0x1.1058p+0f, 0x1.ap+64f},
36       {0x1.fa32d4p-1f, 0x1.67a62ep+12f},
37       {-0x1.8p-49, 0x1.8p+1},
38       {0x1.8p-48, 0x1.8p+1},
39   };
40 
41   for (int i = 0; i < N; ++i) {
42     float x = INPUTS[i].x;
43     float y = INPUTS[i].y;
44     EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Pow, INPUTS[i],
45                                    LIBC_NAMESPACE::powf(x, y), 0.5);
46   }
47 }
48 
TEST_F(LlvmLibcPowfTest,InFloatRange)49 TEST_F(LlvmLibcPowfTest, InFloatRange) {
50   constexpr uint32_t X_COUNT = 1'23;
51   constexpr uint32_t X_START = FPBits(0.25f).uintval();
52   constexpr uint32_t X_STOP = FPBits(4.0f).uintval();
53   constexpr uint32_t X_STEP = (X_STOP - X_START) / X_COUNT;
54 
55   constexpr uint32_t Y_COUNT = 1'37;
56   constexpr uint32_t Y_START = FPBits(0.25f).uintval();
57   constexpr uint32_t Y_STOP = FPBits(4.0f).uintval();
58   constexpr uint32_t Y_STEP = (Y_STOP - Y_START) / Y_COUNT;
59 
60   auto test = [&](mpfr::RoundingMode rounding_mode) {
61     mpfr::ForceRoundingMode __r(rounding_mode);
62     if (!__r.success)
63       return;
64 
65     uint64_t fails = 0;
66     uint64_t count = 0;
67     uint64_t cc = 0;
68     float mx, my, mr = 0.0;
69     double tol = 0.5;
70 
71     for (uint32_t i = 0, v = X_START; i <= X_COUNT; ++i, v += X_STEP) {
72       float x = FPBits(v).get_val();
73       if (FPBits(v).is_nan() || FPBits(v).is_inf() || x < 0.0)
74         continue;
75 
76       for (uint32_t j = 0, w = Y_START; j <= Y_COUNT; ++j, w += Y_STEP) {
77         float y = FPBits(w).get_val();
78         if (FPBits(w).is_nan() || FPBits(w).is_inf())
79           continue;
80 
81         LIBC_NAMESPACE::libc_errno = 0;
82         float result = LIBC_NAMESPACE::powf(x, y);
83         ++cc;
84         if (FPBits(result).is_nan() || FPBits(result).is_inf())
85           continue;
86 
87         ++count;
88         mpfr::BinaryInput<float> inputs{x, y};
89 
90         if (!TEST_MPFR_MATCH_ROUNDING_SILENTLY(mpfr::Operation::Pow, inputs,
91                                                result, 0.5, rounding_mode)) {
92           ++fails;
93           while (!TEST_MPFR_MATCH_ROUNDING_SILENTLY(
94               mpfr::Operation::Pow, inputs, result, tol, rounding_mode)) {
95             mx = x;
96             my = y;
97             mr = result;
98 
99             if (tol > 1000.0)
100               break;
101 
102             tol *= 2.0;
103           }
104         }
105       }
106     }
107     if (fails || (count < cc)) {
108       tlog << " Powf failed: " << fails << "/" << count << "/" << cc
109            << " tests.\n"
110            << "   Max ULPs is at most: " << static_cast<uint64_t>(tol) << ".\n";
111     }
112     if (fails) {
113       mpfr::BinaryInput<float> inputs{mx, my};
114       EXPECT_MPFR_MATCH(mpfr::Operation::Pow, inputs, mr, 0.5, rounding_mode);
115     }
116   };
117 
118   tlog << " Test Rounding To Nearest...\n";
119   test(mpfr::RoundingMode::Nearest);
120 
121   tlog << " Test Rounding Downward...\n";
122   test(mpfr::RoundingMode::Downward);
123 
124   tlog << " Test Rounding Upward...\n";
125   test(mpfr::RoundingMode::Upward);
126 
127   tlog << " Test Rounding Toward Zero...\n";
128   test(mpfr::RoundingMode::TowardZero);
129 }
130