1 // Copyright 2016 The Fuchsia Authors
2 //
3 // Use of this source code is governed by a MIT-style
4 // license that can be found in the LICENSE file or at
5 // https://opensource.org/licenses/MIT
6
7 #include <lib/unittest/unittest.h>
8 #include <limits.h>
9 #include <pow2.h>
10
pow2_test(void)11 static bool pow2_test(void) {
12 const size_t num_uint_bits = sizeof(uint) * CHAR_BIT;
13 const size_t num_ulong_bits = sizeof(ulong) * CHAR_BIT;
14
15 BEGIN_TEST;
16 EXPECT_EQ(0u, log2_uint_floor(0), "");
17 EXPECT_EQ(0u, log2_uint_floor(1), "");
18 EXPECT_EQ(1u, log2_uint_floor(2), "");
19 EXPECT_EQ(1u, log2_uint_floor(3), "");
20 EXPECT_EQ(2u, log2_uint_floor(4), "");
21 EXPECT_EQ(num_uint_bits - 2, log2_uint_floor(UINT_MAX >> 1), "");
22 EXPECT_EQ(num_uint_bits - 1, log2_uint_floor((UINT_MAX >> 1) + 1), "");
23 EXPECT_EQ(num_uint_bits - 1, log2_uint_floor(UINT_MAX), "");
24
25 EXPECT_EQ(0u, log2_uint_ceil(0), "");
26 EXPECT_EQ(0u, log2_uint_ceil(1), "");
27 EXPECT_EQ(1u, log2_uint_ceil(2), "");
28 EXPECT_EQ(2u, log2_uint_ceil(3), "");
29 EXPECT_EQ(2u, log2_uint_ceil(4), "");
30 EXPECT_EQ(3u, log2_uint_ceil(5), "");
31 EXPECT_EQ(num_uint_bits - 1, log2_uint_ceil(UINT_MAX >> 1), "");
32 EXPECT_EQ(num_uint_bits - 1, log2_uint_ceil((UINT_MAX >> 1) + 1), "");
33 EXPECT_EQ(num_uint_bits, log2_uint_ceil((UINT_MAX >> 1) + 2), "");
34 EXPECT_EQ(num_uint_bits, log2_uint_ceil(UINT_MAX), "");
35
36 EXPECT_EQ(0u, log2_ulong_floor(0), "");
37 EXPECT_EQ(0u, log2_ulong_floor(1), "");
38 EXPECT_EQ(1u, log2_ulong_floor(2), "");
39 EXPECT_EQ(1u, log2_ulong_floor(3), "");
40 EXPECT_EQ(2u, log2_ulong_floor(4), "");
41 EXPECT_EQ(num_ulong_bits - 2, log2_ulong_floor(ULONG_MAX >> 1), "");
42 EXPECT_EQ(num_ulong_bits - 1, log2_ulong_floor((ULONG_MAX >> 1) + 1), "");
43 EXPECT_EQ(num_ulong_bits - 1, log2_ulong_floor(ULONG_MAX), "");
44
45 EXPECT_EQ(0u, log2_ulong_ceil(0), "");
46 EXPECT_EQ(0u, log2_ulong_ceil(1), "");
47 EXPECT_EQ(1u, log2_ulong_ceil(2), "");
48 EXPECT_EQ(2u, log2_ulong_ceil(3), "");
49 EXPECT_EQ(2u, log2_ulong_ceil(4), "");
50 EXPECT_EQ(3u, log2_ulong_ceil(5), "");
51 EXPECT_EQ(num_ulong_bits - 1, log2_ulong_ceil(ULONG_MAX >> 1), "");
52 EXPECT_EQ(num_ulong_bits - 1, log2_ulong_ceil((ULONG_MAX >> 1) + 1), "");
53 EXPECT_EQ(num_ulong_bits, log2_ulong_ceil((ULONG_MAX >> 1) + 2), "");
54 EXPECT_EQ(num_ulong_bits, log2_ulong_ceil(ULONG_MAX), "");
55
56 EXPECT_TRUE(ispow2(0), "");
57 for (size_t i = 0; i < num_uint_bits; ++i) {
58 EXPECT_TRUE(ispow2(1u << i), "");
59 }
60 EXPECT_FALSE(ispow2(3), "");
61 EXPECT_FALSE(ispow2(5), "");
62 EXPECT_FALSE(ispow2(6), "");
63 EXPECT_FALSE(ispow2(7), "");
64 EXPECT_FALSE(ispow2(UINT_MAX), "");
65
66 EXPECT_EQ(0u, round_up_pow2_u32(0), "");
67 EXPECT_EQ(1u, round_up_pow2_u32(1), "");
68 EXPECT_EQ(2u, round_up_pow2_u32(2), "");
69 EXPECT_EQ(4u, round_up_pow2_u32(3), "");
70 EXPECT_EQ(8u, round_up_pow2_u32(5), "");
71 EXPECT_EQ(8u, round_up_pow2_u32(7), "");
72 EXPECT_EQ(1u << 31, round_up_pow2_u32(1u << 31), "");
73 EXPECT_EQ(0u, round_up_pow2_u32((1u << 31) + 1), "");
74 EXPECT_EQ(0u, round_up_pow2_u32(UINT_MAX), "");
75 END_TEST;
76 }
77
78 UNITTEST_START_TESTCASE(pow2_tests)
79 UNITTEST("pow2 lib tests", pow2_test)
80 UNITTEST_END_TESTCASE(pow2_tests, "pow2", "pow2 lib tests");
81