1 //===- unittests/Support/MathExtrasTest.cpp - math utils tests ------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 #include "gtest/gtest.h"
11 #include "llvm/Support/MathExtras.h"
12
13 using namespace llvm;
14
15 namespace {
16
TEST(MathExtras,countTrailingZeros)17 TEST(MathExtras, countTrailingZeros) {
18 uint8_t Z8 = 0;
19 uint16_t Z16 = 0;
20 uint32_t Z32 = 0;
21 uint64_t Z64 = 0;
22 EXPECT_EQ(8u, countTrailingZeros(Z8));
23 EXPECT_EQ(16u, countTrailingZeros(Z16));
24 EXPECT_EQ(32u, countTrailingZeros(Z32));
25 EXPECT_EQ(64u, countTrailingZeros(Z64));
26
27 uint8_t NZ8 = 42;
28 uint16_t NZ16 = 42;
29 uint32_t NZ32 = 42;
30 uint64_t NZ64 = 42;
31 EXPECT_EQ(1u, countTrailingZeros(NZ8));
32 EXPECT_EQ(1u, countTrailingZeros(NZ16));
33 EXPECT_EQ(1u, countTrailingZeros(NZ32));
34 EXPECT_EQ(1u, countTrailingZeros(NZ64));
35 }
36
TEST(MathExtras,countLeadingZeros)37 TEST(MathExtras, countLeadingZeros) {
38 uint8_t Z8 = 0;
39 uint16_t Z16 = 0;
40 uint32_t Z32 = 0;
41 uint64_t Z64 = 0;
42 EXPECT_EQ(8u, countLeadingZeros(Z8));
43 EXPECT_EQ(16u, countLeadingZeros(Z16));
44 EXPECT_EQ(32u, countLeadingZeros(Z32));
45 EXPECT_EQ(64u, countLeadingZeros(Z64));
46
47 uint8_t NZ8 = 42;
48 uint16_t NZ16 = 42;
49 uint32_t NZ32 = 42;
50 uint64_t NZ64 = 42;
51 EXPECT_EQ(2u, countLeadingZeros(NZ8));
52 EXPECT_EQ(10u, countLeadingZeros(NZ16));
53 EXPECT_EQ(26u, countLeadingZeros(NZ32));
54 EXPECT_EQ(58u, countLeadingZeros(NZ64));
55
56 EXPECT_EQ(8u, countLeadingZeros(0x00F000FFu));
57 EXPECT_EQ(8u, countLeadingZeros(0x00F12345u));
58 for (unsigned i = 0; i <= 30; ++i) {
59 EXPECT_EQ(31 - i, countLeadingZeros(1u << i));
60 }
61
62 EXPECT_EQ(8u, countLeadingZeros(0x00F1234500F12345ULL));
63 EXPECT_EQ(1u, countLeadingZeros(1ULL << 62));
64 for (unsigned i = 0; i <= 62; ++i) {
65 EXPECT_EQ(63 - i, countLeadingZeros(1ULL << i));
66 }
67 }
68
TEST(MathExtras,findFirstSet)69 TEST(MathExtras, findFirstSet) {
70 uint8_t Z8 = 0;
71 uint16_t Z16 = 0;
72 uint32_t Z32 = 0;
73 uint64_t Z64 = 0;
74 EXPECT_EQ(0xFFULL, findFirstSet(Z8));
75 EXPECT_EQ(0xFFFFULL, findFirstSet(Z16));
76 EXPECT_EQ(0xFFFFFFFFULL, findFirstSet(Z32));
77 EXPECT_EQ(0xFFFFFFFFFFFFFFFFULL, findFirstSet(Z64));
78
79 uint8_t NZ8 = 42;
80 uint16_t NZ16 = 42;
81 uint32_t NZ32 = 42;
82 uint64_t NZ64 = 42;
83 EXPECT_EQ(1u, findFirstSet(NZ8));
84 EXPECT_EQ(1u, findFirstSet(NZ16));
85 EXPECT_EQ(1u, findFirstSet(NZ32));
86 EXPECT_EQ(1u, findFirstSet(NZ64));
87 }
88
TEST(MathExtras,findLastSet)89 TEST(MathExtras, findLastSet) {
90 uint8_t Z8 = 0;
91 uint16_t Z16 = 0;
92 uint32_t Z32 = 0;
93 uint64_t Z64 = 0;
94 EXPECT_EQ(0xFFULL, findLastSet(Z8));
95 EXPECT_EQ(0xFFFFULL, findLastSet(Z16));
96 EXPECT_EQ(0xFFFFFFFFULL, findLastSet(Z32));
97 EXPECT_EQ(0xFFFFFFFFFFFFFFFFULL, findLastSet(Z64));
98
99 uint8_t NZ8 = 42;
100 uint16_t NZ16 = 42;
101 uint32_t NZ32 = 42;
102 uint64_t NZ64 = 42;
103 EXPECT_EQ(5u, findLastSet(NZ8));
104 EXPECT_EQ(5u, findLastSet(NZ16));
105 EXPECT_EQ(5u, findLastSet(NZ32));
106 EXPECT_EQ(5u, findLastSet(NZ64));
107 }
108
TEST(MathExtras,reverseBits)109 TEST(MathExtras, reverseBits) {
110 uint8_t NZ8 = 42;
111 uint16_t NZ16 = 42;
112 uint32_t NZ32 = 42;
113 uint64_t NZ64 = 42;
114 EXPECT_EQ(0x54ULL, reverseBits(NZ8));
115 EXPECT_EQ(0x5400ULL, reverseBits(NZ16));
116 EXPECT_EQ(0x54000000ULL, reverseBits(NZ32));
117 EXPECT_EQ(0x5400000000000000ULL, reverseBits(NZ64));
118 }
119
TEST(MathExtras,isPowerOf2_32)120 TEST(MathExtras, isPowerOf2_32) {
121 EXPECT_TRUE(isPowerOf2_32(1 << 6));
122 EXPECT_TRUE(isPowerOf2_32(1 << 12));
123 EXPECT_FALSE(isPowerOf2_32((1 << 19) + 3));
124 EXPECT_FALSE(isPowerOf2_32(0xABCDEF0));
125 }
126
TEST(MathExtras,isPowerOf2_64)127 TEST(MathExtras, isPowerOf2_64) {
128 EXPECT_TRUE(isPowerOf2_64(1LL << 46));
129 EXPECT_TRUE(isPowerOf2_64(1LL << 12));
130 EXPECT_FALSE(isPowerOf2_64((1LL << 53) + 3));
131 EXPECT_FALSE(isPowerOf2_64(0xABCDEF0ABCDEF0LL));
132 }
133
TEST(MathExtras,ByteSwap_32)134 TEST(MathExtras, ByteSwap_32) {
135 EXPECT_EQ(0x44332211u, ByteSwap_32(0x11223344));
136 EXPECT_EQ(0xDDCCBBAAu, ByteSwap_32(0xAABBCCDD));
137 }
138
TEST(MathExtras,ByteSwap_64)139 TEST(MathExtras, ByteSwap_64) {
140 EXPECT_EQ(0x8877665544332211ULL, ByteSwap_64(0x1122334455667788LL));
141 EXPECT_EQ(0x1100FFEEDDCCBBAAULL, ByteSwap_64(0xAABBCCDDEEFF0011LL));
142 }
143
TEST(MathExtras,countLeadingOnes)144 TEST(MathExtras, countLeadingOnes) {
145 for (int i = 30; i >= 0; --i) {
146 // Start with all ones and unset some bit.
147 EXPECT_EQ(31u - i, countLeadingOnes(0xFFFFFFFF ^ (1 << i)));
148 }
149 for (int i = 62; i >= 0; --i) {
150 // Start with all ones and unset some bit.
151 EXPECT_EQ(63u - i, countLeadingOnes(0xFFFFFFFFFFFFFFFFULL ^ (1LL << i)));
152 }
153 for (int i = 30; i >= 0; --i) {
154 // Start with all ones and unset some bit.
155 EXPECT_EQ(31u - i, countLeadingOnes(0xFFFFFFFF ^ (1 << i)));
156 }
157 }
158
TEST(MathExtras,FloatBits)159 TEST(MathExtras, FloatBits) {
160 static const float kValue = 5632.34f;
161 EXPECT_FLOAT_EQ(kValue, BitsToFloat(FloatToBits(kValue)));
162 }
163
TEST(MathExtras,DoubleBits)164 TEST(MathExtras, DoubleBits) {
165 static const double kValue = 87987234.983498;
166 EXPECT_FLOAT_EQ(kValue, BitsToDouble(DoubleToBits(kValue)));
167 }
168
TEST(MathExtras,MinAlign)169 TEST(MathExtras, MinAlign) {
170 EXPECT_EQ(1u, MinAlign(2, 3));
171 EXPECT_EQ(2u, MinAlign(2, 4));
172 EXPECT_EQ(1u, MinAlign(17, 64));
173 EXPECT_EQ(256u, MinAlign(256, 512));
174 }
175
TEST(MathExtras,NextPowerOf2)176 TEST(MathExtras, NextPowerOf2) {
177 EXPECT_EQ(4u, NextPowerOf2(3));
178 EXPECT_EQ(16u, NextPowerOf2(15));
179 EXPECT_EQ(256u, NextPowerOf2(128));
180 }
181
TEST(MathExtras,RoundUpToAlignment)182 TEST(MathExtras, RoundUpToAlignment) {
183 EXPECT_EQ(8u, RoundUpToAlignment(5, 8));
184 EXPECT_EQ(24u, RoundUpToAlignment(17, 8));
185 EXPECT_EQ(0u, RoundUpToAlignment(~0LL, 8));
186 }
187
188 }
189