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 "src/__support/FPUtil/FPBits.h"
10 #include "src/math/exp2f.h"
11 #include "utils/MPFRWrapper/MPFRUtils.h"
12 #include "utils/UnitTest/FPMatcher.h"
13 #include "utils/UnitTest/Test.h"
14 #include <math.h>
15
16 #include <errno.h>
17 #include <stdint.h>
18
19 namespace mpfr = __llvm_libc::testing::mpfr;
20
21 DECLARE_SPECIAL_CONSTANTS(float)
22
TEST(LlvmLibcExp2fTest,SpecialNumbers)23 TEST(LlvmLibcExp2fTest, SpecialNumbers) {
24 errno = 0;
25
26 EXPECT_FP_EQ(aNaN, __llvm_libc::exp2f(aNaN));
27 EXPECT_MATH_ERRNO(0);
28
29 EXPECT_FP_EQ(inf, __llvm_libc::exp2f(inf));
30 EXPECT_MATH_ERRNO(0);
31
32 EXPECT_FP_EQ(0.0f, __llvm_libc::exp2f(neg_inf));
33 EXPECT_MATH_ERRNO(0);
34
35 EXPECT_FP_EQ(1.0f, __llvm_libc::exp2f(0.0f));
36 EXPECT_MATH_ERRNO(0);
37
38 EXPECT_FP_EQ(1.0f, __llvm_libc::exp2f(-0.0f));
39 EXPECT_MATH_ERRNO(0);
40 }
41
TEST(LlvmLibcExp2fTest,Overflow)42 TEST(LlvmLibcExp2fTest, Overflow) {
43 errno = 0;
44 EXPECT_FP_EQ(inf, __llvm_libc::exp2f(float(FPBits(0x7f7fffffU))));
45 EXPECT_MATH_ERRNO(ERANGE);
46
47 EXPECT_FP_EQ(inf, __llvm_libc::exp2f(float(FPBits(0x43000000U))));
48 EXPECT_MATH_ERRNO(ERANGE);
49
50 EXPECT_FP_EQ(inf, __llvm_libc::exp2f(float(FPBits(0x43000001U))));
51 EXPECT_MATH_ERRNO(ERANGE);
52 }
53
TEST(LlvmLibcExp2fTest,TrickyInputs)54 TEST(LlvmLibcExp2fTest, TrickyInputs) {
55 constexpr int N = 12;
56 constexpr uint32_t INPUTS[N] = {
57 0x3b429d37U, /*0x1.853a6ep-9f*/
58 0x3c02a9adU, /*0x1.05535ap-7f*/
59 0x3ca66e26U, /*0x1.4cdc4cp-6f*/
60 0x3d92a282U, /*0x1.254504p-4f*/
61 0x42fa0001U, /*0x1.f40002p+6f*/
62 0x42ffffffU, /*0x1.fffffep+6f*/
63 0xb8d3d026U, /*-0x1.a7a04cp-14f*/
64 0xbcf3a937U, /*-0x1.e7526ep-6f*/
65 0xc2fa0001U, /*-0x1.f40002p+6f*/
66 0xc2fc0000U, /*-0x1.f8p+6f*/
67 0xc2fc0001U, /*-0x1.f80002p+6f*/
68 0xc3150000U, /*-0x1.2ap+7f*/
69 };
70 for (int i = 0; i < N; ++i) {
71 errno = 0;
72 float x = float(FPBits(INPUTS[i]));
73 EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
74 __llvm_libc::exp2f(x), 0.5);
75 EXPECT_MATH_ERRNO(0);
76 }
77 }
78
TEST(LlvmLibcExp2fTest,Underflow)79 TEST(LlvmLibcExp2fTest, Underflow) {
80 errno = 0;
81 EXPECT_FP_EQ(0.0f, __llvm_libc::exp2f(float(FPBits(0xff7fffffU))));
82 EXPECT_MATH_ERRNO(ERANGE);
83
84 float x = float(FPBits(0xc3158000U));
85 EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
86 __llvm_libc::exp2f(x), 0.5);
87 EXPECT_MATH_ERRNO(0);
88
89 x = float(FPBits(0xc3160000U));
90 EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
91 __llvm_libc::exp2f(x), 0.5);
92 EXPECT_MATH_ERRNO(ERANGE);
93
94 x = float(FPBits(0xc3165432U));
95 EXPECT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
96 __llvm_libc::exp2f(x), 0.5);
97 EXPECT_MATH_ERRNO(ERANGE);
98 }
99
TEST(LlvmLibcExp2fTest,InFloatRange)100 TEST(LlvmLibcExp2fTest, InFloatRange) {
101 constexpr uint32_t COUNT = 1000000;
102 constexpr uint32_t STEP = UINT32_MAX / COUNT;
103 for (uint32_t i = 0, v = 0; i <= COUNT; ++i, v += STEP) {
104 float x = float(FPBits(v));
105 if (isnan(x) || isinf(x))
106 continue;
107 errno = 0;
108 float result = __llvm_libc::exp2f(x);
109
110 // If the computation resulted in an error or did not produce valid result
111 // in the single-precision floating point range, then ignore comparing with
112 // MPFR result as MPFR can still produce valid results because of its
113 // wider precision.
114 if (isnan(result) || isinf(result) || errno != 0)
115 continue;
116 ASSERT_MPFR_MATCH_ALL_ROUNDING(mpfr::Operation::Exp2, x,
117 __llvm_libc::exp2f(x), 0.5);
118 }
119 }
120