1//===-- Unittests for expm1f-----------------------------------------------===//
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/expm1f.h"
13#include "test/UnitTest/FPMatcher.h"
14#include "test/UnitTest/Test.h"
15#include "utils/MPFRWrapper/MPFRUtils.h"
16
17#include <stdint.h>
18
19using LlvmLibcExpm1fTest = LIBC_NAMESPACE::testing::FPTest<float>;
20
21namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
22
23TEST_F(LlvmLibcExpm1fTest, SpecialNumbers) {
24 LIBC_NAMESPACE::libc_errno = 0;
25
26 EXPECT_FP_EQ(aNaN, LIBC_NAMESPACE::expm1f(aNaN));
27 EXPECT_MATH_ERRNO(0);
28
29 EXPECT_FP_EQ(inf, LIBC_NAMESPACE::expm1f(inf));
30 EXPECT_MATH_ERRNO(0);
31
32 EXPECT_FP_EQ(-1.0f, LIBC_NAMESPACE::expm1f(neg_inf));
33 EXPECT_MATH_ERRNO(0);
34
35 EXPECT_FP_EQ(0.0f, LIBC_NAMESPACE::expm1f(0.0f));
36 EXPECT_MATH_ERRNO(0);
37
38 EXPECT_FP_EQ(-0.0f, LIBC_NAMESPACE::expm1f(-0.0f));
39 EXPECT_MATH_ERRNO(0);
40}
41
42TEST_F(LlvmLibcExpm1fTest, Overflow) {
43 LIBC_NAMESPACE::libc_errno = 0;
44 EXPECT_FP_EQ_WITH_EXCEPTION(
45 inf, LIBC_NAMESPACE::expm1f(FPBits(0x7f7fffffU).get_val()), FE_OVERFLOW);
46 EXPECT_MATH_ERRNO(ERANGE);
47
48 EXPECT_FP_EQ_WITH_EXCEPTION(
49 inf, LIBC_NAMESPACE::expm1f(FPBits(0x42cffff8U).get_val()), FE_OVERFLOW);
50 EXPECT_MATH_ERRNO(ERANGE);
51
52 EXPECT_FP_EQ_WITH_EXCEPTION(
53 inf, LIBC_NAMESPACE::expm1f(FPBits(0x42d00008U).get_val()), FE_OVERFLOW);
54 EXPECT_MATH_ERRNO(ERANGE);
55}
56
57TEST_F(LlvmLibcExpm1fTest, Underflow) {
58 LIBC_NAMESPACE::libc_errno = 0;
59 EXPECT_FP_EQ(-1.0f, LIBC_NAMESPACE::expm1f(FPBits(0xff7fffffU).get_val()));
60
61 float x = FPBits(0xc2cffff8U).get_val();
62 EXPECT_FP_EQ(-1.0f, LIBC_NAMESPACE::expm1f(x));
63
64 x = FPBits(0xc2d00008U).get_val();
65 EXPECT_FP_EQ(-1.0f, LIBC_NAMESPACE::expm1f(x));
66}
67
68// Test with inputs which are the borders of underflow/overflow but still
69// produce valid results without setting errno.
70TEST_F(LlvmLibcExpm1fTest, Borderline) {
71 float x;
72
73 LIBC_NAMESPACE::libc_errno = 0;
74 x = FPBits(0x42affff8U).get_val();
75 ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Expm1, x,
76 LIBC_NAMESPACE::expm1f(x), 0.5);
77 EXPECT_MATH_ERRNO(0);
78
79 x = FPBits(0x42b00008U).get_val();
80 ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Expm1, x,
81 LIBC_NAMESPACE::expm1f(x), 0.5);
82 EXPECT_MATH_ERRNO(0);
83
84 x = FPBits(0xc2affff8U).get_val();
85 ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Expm1, x,
86 LIBC_NAMESPACE::expm1f(x), 0.5);
87 EXPECT_MATH_ERRNO(0);
88
89 x = FPBits(0xc2b00008U).get_val();
90 ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Expm1, x,
91 LIBC_NAMESPACE::expm1f(x), 0.5);
92 EXPECT_MATH_ERRNO(0);
93
94 x = FPBits(0x3dc252ddU).get_val();
95 ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Expm1, x,
96 LIBC_NAMESPACE::expm1f(x), 0.5);
97 EXPECT_MATH_ERRNO(0);
98
99 x = FPBits(0x3e35bec5U).get_val();
100 ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Expm1, x,
101 LIBC_NAMESPACE::expm1f(x), 0.5);
102 EXPECT_MATH_ERRNO(0);
103
104 x = FPBits(0x942ed494U).get_val();
105 ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Expm1, x,
106 LIBC_NAMESPACE::expm1f(x), 0.5);
107 EXPECT_MATH_ERRNO(0);
108
109 x = FPBits(0xbdc1c6cbU).get_val();
110 ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Expm1, x,
111 LIBC_NAMESPACE::expm1f(x), 0.5);
112 EXPECT_MATH_ERRNO(0);
113}
114
115TEST_F(LlvmLibcExpm1fTest, InFloatRange) {
116 constexpr uint32_t COUNT = 100'000;
117 constexpr uint32_t STEP = UINT32_MAX / COUNT;
118 for (uint32_t i = 0, v = 0; i <= COUNT; ++i, v += STEP) {
119 float x = FPBits(v).get_val();
120 if (isnan(x: x) || isinf(x: x))
121 continue;
122 LIBC_NAMESPACE::libc_errno = 0;
123 float result = LIBC_NAMESPACE::expm1f(x);
124
125 // If the computation resulted in an error or did not produce valid result
126 // in the single-precision floating point range, then ignore comparing with
127 // MPFR result as MPFR can still produce valid results because of its
128 // wider precision.
129 if (isnan(x: result) || isinf(x: result) || LIBC_NAMESPACE::libc_errno != 0)
130 continue;
131 ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Expm1, x,
132 LIBC_NAMESPACE::expm1f(x), 0.5);
133 }
134}
135

source code of libc/test/src/math/expm1f_test.cpp