1//===-- Unittests for exp2f -----------------------------------------------===//
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/__support/libc_errno.h"
12#include "src/math/exp2f.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 LlvmLibcExp2fTest = LIBC_NAMESPACE::testing::FPTest<float>;
20
21namespace mpfr = LIBC_NAMESPACE::testing::mpfr;
22
23TEST_F(LlvmLibcExp2fTest, SpecialNumbers) {
24 libc_errno = 0;
25
26 EXPECT_FP_EQ(aNaN, LIBC_NAMESPACE::exp2f(aNaN));
27 EXPECT_MATH_ERRNO(0);
28
29 EXPECT_FP_EQ(inf, LIBC_NAMESPACE::exp2f(inf));
30 EXPECT_MATH_ERRNO(0);
31
32 EXPECT_FP_EQ(0.0f, LIBC_NAMESPACE::exp2f(neg_inf));
33 EXPECT_MATH_ERRNO(0);
34
35 EXPECT_FP_EQ(1.0f, LIBC_NAMESPACE::exp2f(0.0f));
36 EXPECT_MATH_ERRNO(0);
37
38 EXPECT_FP_EQ(1.0f, LIBC_NAMESPACE::exp2f(-0.0f));
39 EXPECT_MATH_ERRNO(0);
40}
41
42TEST_F(LlvmLibcExp2fTest, Overflow) {
43 libc_errno = 0;
44 EXPECT_FP_EQ_WITH_EXCEPTION(
45 inf, LIBC_NAMESPACE::exp2f(FPBits(0x7f7fffffU).get_val()), FE_OVERFLOW);
46 EXPECT_MATH_ERRNO(ERANGE);
47
48 EXPECT_FP_EQ_WITH_EXCEPTION(
49 inf, LIBC_NAMESPACE::exp2f(FPBits(0x43000000U).get_val()), FE_OVERFLOW);
50 EXPECT_MATH_ERRNO(ERANGE);
51
52 EXPECT_FP_EQ_WITH_EXCEPTION(
53 inf, LIBC_NAMESPACE::exp2f(FPBits(0x43000001U).get_val()), FE_OVERFLOW);
54 EXPECT_MATH_ERRNO(ERANGE);
55}
56
57TEST_F(LlvmLibcExp2fTest, TrickyInputs) {
58 constexpr int N = 12;
59 constexpr uint32_t INPUTS[N] = {
60 0x3b429d37U, /*0x1.853a6ep-9f*/
61 0x3c02a9adU, /*0x1.05535ap-7f*/
62 0x3ca66e26U, /*0x1.4cdc4cp-6f*/
63 0x3d92a282U, /*0x1.254504p-4f*/
64 0x42fa0001U, /*0x1.f40002p+6f*/
65 0x42ffffffU, /*0x1.fffffep+6f*/
66 0xb8d3d026U, /*-0x1.a7a04cp-14f*/
67 0xbcf3a937U, /*-0x1.e7526ep-6f*/
68 0xc2fa0001U, /*-0x1.f40002p+6f*/
69 0xc2fc0000U, /*-0x1.f8p+6f*/
70 0xc2fc0001U, /*-0x1.f80002p+6f*/
71 0xc3150000U, /*-0x1.2ap+7f*/
72 };
73 for (int i = 0; i < N; ++i) {
74 libc_errno = 0;
75 float x = FPBits(INPUTS[i]).get_val();
76 EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
77 LIBC_NAMESPACE::exp2f(x), 0.5);
78 EXPECT_MATH_ERRNO(0);
79 }
80}
81
82TEST_F(LlvmLibcExp2fTest, Underflow) {
83 libc_errno = 0;
84 EXPECT_FP_EQ_WITH_EXCEPTION(
85 0.0f, LIBC_NAMESPACE::exp2f(FPBits(0xff7fffffU).get_val()), FE_UNDERFLOW);
86 EXPECT_MATH_ERRNO(ERANGE);
87
88 float x = FPBits(0xc3158000U).get_val();
89 EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
90 LIBC_NAMESPACE::exp2f(x), 0.5);
91 EXPECT_MATH_ERRNO(0);
92
93 x = FPBits(0xc3160000U).get_val();
94 EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
95 LIBC_NAMESPACE::exp2f(x), 0.5);
96 EXPECT_MATH_ERRNO(ERANGE);
97
98 x = FPBits(0xc3165432U).get_val();
99 EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
100 LIBC_NAMESPACE::exp2f(x), 0.5);
101 EXPECT_MATH_ERRNO(ERANGE);
102}
103
104TEST_F(LlvmLibcExp2fTest, InFloatRange) {
105 constexpr uint32_t COUNT = 100'000;
106 constexpr uint32_t STEP = UINT32_MAX / COUNT;
107 for (uint32_t i = 0, v = 0; i <= COUNT; ++i, v += STEP) {
108 float x = FPBits(v).get_val();
109 if (FPBits(v).is_nan() || FPBits(v).is_inf())
110 continue;
111 libc_errno = 0;
112 float result = LIBC_NAMESPACE::exp2f(x);
113
114 // If the computation resulted in an error or did not produce valid result
115 // in the single-precision floating point range, then ignore comparing with
116 // MPFR result as MPFR can still produce valid results because of its
117 // wider precision.
118 if (FPBits(result).is_nan() || FPBits(result).is_inf() || libc_errno != 0)
119 continue;
120 ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
121 LIBC_NAMESPACE::exp2f(x), 0.5);
122 }
123}
124

source code of libc/test/src/math/exp2f_test.cpp