xref: /aosp_15_r20/external/llvm-libc/test/src/math/LogbTest.h (revision 71db0c75aadcf003ffe3238005f61d7618a3fead)
1 //===-- Utility class to test logb[f|l] -------------------------*- C++ -*-===//
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/ManipulationFunctions.h"
10 #include "test/UnitTest/FEnvSafeTest.h"
11 #include "test/UnitTest/FPMatcher.h"
12 #include "test/UnitTest/Test.h"
13 #include "utils/MPFRWrapper/MPFRUtils.h"
14 
15 #include "hdr/math_macros.h"
16 
17 namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
18 
19 template <typename T>
20 class LogbTest : public LIBC_NAMESPACE::testing::FEnvSafeTest {
21 
22   DECLARE_SPECIAL_CONSTANTS(T)
23 
24   static constexpr StorageType HIDDEN_BIT =
25       StorageType(1) << LIBC_NAMESPACE::fputil::FPBits<T>::FRACTION_LEN;
26 
27 public:
28   typedef T (*LogbFunc)(T);
29 
testSpecialNumbers(LogbFunc func)30   void testSpecialNumbers(LogbFunc func) {
31     ASSERT_FP_EQ(aNaN, func(aNaN));
32     ASSERT_FP_EQ(inf, func(inf));
33     ASSERT_FP_EQ(inf, func(neg_inf));
34     ASSERT_FP_EQ(neg_inf, func(0.0));
35     ASSERT_FP_EQ(neg_inf, func(-0.0));
36   }
37 
testPowersOfTwo(LogbFunc func)38   void testPowersOfTwo(LogbFunc func) {
39     EXPECT_FP_EQ(T(0.0), func(T(1.0)));
40     EXPECT_FP_EQ(T(0.0), func(T(-1.0)));
41 
42     EXPECT_FP_EQ(T(1.0), func(T(2.0)));
43     EXPECT_FP_EQ(T(1.0), func(T(-2.0)));
44 
45     EXPECT_FP_EQ(T(2.0), func(T(4.0)));
46     EXPECT_FP_EQ(T(2.0), func(T(-4.0)));
47 
48     EXPECT_FP_EQ(T(3.0), func(T(8.0)));
49     EXPECT_FP_EQ(T(3.0), func(T(-8.0)));
50 
51     EXPECT_FP_EQ(T(4.0), func(T(16.0)));
52     EXPECT_FP_EQ(T(4.0), func(T(-16.0)));
53 
54     EXPECT_FP_EQ(T(5.0), func(T(32.0)));
55     EXPECT_FP_EQ(T(5.0), func(T(-32.0)));
56   }
57 
testSomeIntegers(LogbFunc func)58   void testSomeIntegers(LogbFunc func) {
59     EXPECT_FP_EQ(T(1.0), func(T(3.0)));
60     EXPECT_FP_EQ(T(1.0), func(T(-3.0)));
61 
62     EXPECT_FP_EQ(T(2.0), func(T(7.0)));
63     EXPECT_FP_EQ(T(2.0), func(T(-7.0)));
64 
65     EXPECT_FP_EQ(T(3.0), func(T(10.0)));
66     EXPECT_FP_EQ(T(3.0), func(T(-10.0)));
67 
68     EXPECT_FP_EQ(T(4.0), func(T(31.0)));
69     EXPECT_FP_EQ(T(4.0), func(T(-31.0)));
70 
71     EXPECT_FP_EQ(T(5.0), func(T(55.0)));
72     EXPECT_FP_EQ(T(5.0), func(T(-55.0)));
73   }
74 
testRange(LogbFunc func)75   void testRange(LogbFunc func) {
76     using StorageType = typename FPBits::StorageType;
77     constexpr StorageType COUNT = 100'000;
78     constexpr StorageType STEP = STORAGE_MAX / COUNT;
79     for (StorageType i = 0, v = 0; i <= COUNT; ++i, v += STEP) {
80       T x = FPBits(v).get_val();
81       if (FPBits(v).is_nan() || FPBits(v).is_inf() || x == 0.0l)
82         continue;
83 
84       int exponent;
85       LIBC_NAMESPACE::fputil::frexp(x, exponent);
86       ASSERT_FP_EQ(T(exponent), func(x) + T(1.0));
87     }
88   }
89 };
90 
91 #define LIST_LOGB_TESTS(T, func)                                               \
92   using LlvmLibcLogbTest = LogbTest<T>;                                        \
93   TEST_F(LlvmLibcLogbTest, SpecialNumbers) { testSpecialNumbers(&func); }      \
94   TEST_F(LlvmLibcLogbTest, PowersOfTwo) { testPowersOfTwo(&func); }            \
95   TEST_F(LlvmLibcLogbTest, SomeIntegers) { testSomeIntegers(&func); }          \
96   TEST_F(LlvmLibcLogbTest, InRange) { testRange(&func); }
97