1 //===-- Unittests for cosf ------------------------------------------------===//
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 "include/errno.h"
10 #include "include/math.h"
11 #include "src/errno/llvmlibc_errno.h"
12 #include "src/math/cosf.h"
13 #include "test/src/math/sdcomp26094.h"
14 #include "utils/CPP/Array.h"
15 #include "utils/FPUtil/BitPatterns.h"
16 #include "utils/FPUtil/ClassificationFunctions.h"
17 #include "utils/FPUtil/FloatOperations.h"
18 #include "utils/FPUtil/FloatProperties.h"
19 #include "utils/MPFRWrapper/MPFRUtils.h"
20 #include "utils/UnitTest/Test.h"
21 
22 #include <stdint.h>
23 
24 using __llvm_libc::fputil::isNegativeQuietNaN;
25 using __llvm_libc::fputil::isQuietNaN;
26 using __llvm_libc::fputil::valueAsBits;
27 using __llvm_libc::fputil::valueFromBits;
28 
29 using BitPatterns = __llvm_libc::fputil::BitPatterns<float>;
30 
31 using __llvm_libc::testing::sdcomp26094Values;
32 
33 namespace mpfr = __llvm_libc::testing::mpfr;
34 
35 // 12 additional bits of precision over the base precision of a |float|
36 // value.
37 static constexpr mpfr::Tolerance tolerance{mpfr::Tolerance::floatPrecision, 12,
38                                            3 * 0x1000 / 4};
39 
40 TEST(CosfTest, SpecialNumbers) {
41   llvmlibc_errno = 0;
42 
43   EXPECT_TRUE(
44       isQuietNaN(__llvm_libc::cosf(valueFromBits(BitPatterns::aQuietNaN))));
45   EXPECT_EQ(llvmlibc_errno, 0);
46 
47   EXPECT_TRUE(isNegativeQuietNaN(
48       __llvm_libc::cosf(valueFromBits(BitPatterns::aNegativeQuietNaN))));
49   EXPECT_EQ(llvmlibc_errno, 0);
50 
51   EXPECT_TRUE(isQuietNaN(
52       __llvm_libc::cosf(valueFromBits(BitPatterns::aSignallingNaN))));
53   EXPECT_EQ(llvmlibc_errno, 0);
54 
55   EXPECT_TRUE(isNegativeQuietNaN(
56       __llvm_libc::cosf(valueFromBits(BitPatterns::aNegativeSignallingNaN))));
57   EXPECT_EQ(llvmlibc_errno, 0);
58 
59   EXPECT_EQ(BitPatterns::one,
60             valueAsBits(__llvm_libc::cosf(valueFromBits(BitPatterns::zero))));
61   EXPECT_EQ(llvmlibc_errno, 0);
62 
63   EXPECT_EQ(BitPatterns::one, valueAsBits(__llvm_libc::cosf(
64                                   valueFromBits(BitPatterns::negZero))));
65   EXPECT_EQ(llvmlibc_errno, 0);
66 
67   llvmlibc_errno = 0;
68   EXPECT_TRUE(isQuietNaN(__llvm_libc::cosf(valueFromBits(BitPatterns::inf))));
69   EXPECT_EQ(llvmlibc_errno, EDOM);
70 
71   llvmlibc_errno = 0;
72   EXPECT_TRUE(
73       isQuietNaN(__llvm_libc::cosf(valueFromBits(BitPatterns::negInf))));
74   EXPECT_EQ(llvmlibc_errno, EDOM);
75 }
76 
77 TEST(CosfTest, InFloatRange) {
78   constexpr uint32_t count = 1000000;
79   constexpr uint32_t step = UINT32_MAX / count;
80   for (uint32_t i = 0, v = 0; i <= count; ++i, v += step) {
81     float x = valueFromBits(v);
82     if (isnan(x) || isinf(x))
83       continue;
84     ASSERT_MPFR_MATCH(mpfr::Operation::Cos, x, __llvm_libc::cosf(x), tolerance);
85   }
86 }
87 
88 // For small values, cos(x) is 1.
89 TEST(CosfTest, SmallValues) {
90   float x = valueFromBits(0x17800000U);
91   float result = __llvm_libc::cosf(x);
92   EXPECT_MPFR_MATCH(mpfr::Operation::Cos, x, result, tolerance);
93   EXPECT_EQ(BitPatterns::one, valueAsBits(result));
94 
95   x = valueFromBits(0x0040000U);
96   result = __llvm_libc::cosf(x);
97   EXPECT_MPFR_MATCH(mpfr::Operation::Cos, x, result, tolerance);
98   EXPECT_EQ(BitPatterns::one, valueAsBits(result));
99 }
100 
101 // SDCOMP-26094: check cosf in the cases for which the range reducer
102 // returns values furthest beyond its nominal upper bound of pi/4.
103 TEST(CosfTest, SDCOMP_26094) {
104   for (uint32_t v : sdcomp26094Values) {
105     float x = valueFromBits(v);
106     ASSERT_MPFR_MATCH(mpfr::Operation::Cos, x, __llvm_libc::cosf(x), tolerance);
107   }
108 }
109