1 //===-- Unittests for memory_utils ----------------------------------------===//
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/CPP/Array.h"
10 #include "src/string/memory_utils/utils.h"
11 #include "utils/UnitTest/Test.h"
12 
13 namespace __llvm_libc {
14 
TEST(LlvmLibcUtilsTest,IsPowerOfTwoOrZero)15 TEST(LlvmLibcUtilsTest, IsPowerOfTwoOrZero) {
16   static const cpp::Array<bool, 65> kExpectedValues{
17       1, 1, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, // 0-15
18       1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 16-31
19       1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 32-47
20       0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 48-63
21       1                                               // 64
22   };
23   for (size_t i = 0; i < kExpectedValues.size(); ++i)
24     EXPECT_EQ(is_power2_or_zero(i), kExpectedValues[i]);
25 }
26 
TEST(LlvmLibcUtilsTest,IsPowerOfTwo)27 TEST(LlvmLibcUtilsTest, IsPowerOfTwo) {
28   static const cpp::Array<bool, 65> kExpectedValues{
29       0, 1, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, // 0-15
30       1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 16-31
31       1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 32-47
32       0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 48-63
33       1                                               // 64
34   };
35   for (size_t i = 0; i < kExpectedValues.size(); ++i)
36     EXPECT_EQ(is_power2(i), kExpectedValues[i]);
37 }
38 
TEST(LlvmLibcUtilsTest,Log2)39 TEST(LlvmLibcUtilsTest, Log2) {
40   static const cpp::Array<size_t, 65> kExpectedValues{
41       0, 0, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, // 0-15
42       4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, // 16-31
43       5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, // 32-47
44       5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, // 48-63
45       6                                               // 64
46   };
47   for (size_t i = 0; i < kExpectedValues.size(); ++i)
48     EXPECT_EQ(log2(i), kExpectedValues[i]);
49 }
50 
TEST(LlvmLibcUtilsTest,LEPowerOf2)51 TEST(LlvmLibcUtilsTest, LEPowerOf2) {
52   static const cpp::Array<size_t, 65> kExpectedValues{
53       0,  1,  2,  2,  4,  4,  4,  4,  8,  8,  8,  8,  8,  8,  8,  8,  // 0-15
54       16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, 16, // 16-31
55       32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, // 32-47
56       32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, // 48-63
57       64                                                              // 64
58   };
59   for (size_t i = 0; i < kExpectedValues.size(); ++i)
60     EXPECT_EQ(le_power2(i), kExpectedValues[i]);
61 }
62 
TEST(LlvmLibcUtilsTest,GEPowerOf2)63 TEST(LlvmLibcUtilsTest, GEPowerOf2) {
64   static const cpp::Array<size_t, 66> kExpectedValues{
65       0,  1,  2,  4,  4,  8,  8,  8,  8,  16, 16, 16, 16, 16, 16, 16, // 0-15
66       16, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, // 16-31
67       32, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, // 32-47
68       64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, // 48-63
69       64, 128                                                         // 64-65
70   };
71   for (size_t i = 0; i < kExpectedValues.size(); ++i)
72     EXPECT_EQ(ge_power2(i), kExpectedValues[i]);
73 }
74 
75 using I = intptr_t;
76 
77 // Converts an offset into a pointer.
forge(size_t offset)78 const void *forge(size_t offset) {
79   return reinterpret_cast<const void *>(offset);
80 }
81 
TEST(LlvmLibcUtilsTest,OffsetToNextAligned)82 TEST(LlvmLibcUtilsTest, OffsetToNextAligned) {
83   EXPECT_EQ(offset_to_next_aligned<16>(forge(0)), I(0));
84   EXPECT_EQ(offset_to_next_aligned<16>(forge(1)), I(15));
85   EXPECT_EQ(offset_to_next_aligned<16>(forge(16)), I(0));
86   EXPECT_EQ(offset_to_next_aligned<16>(forge(15)), I(1));
87   EXPECT_EQ(offset_to_next_aligned<32>(forge(16)), I(16));
88 }
89 
TEST(LlvmLibcUtilsTest,OffsetFromLastAligned)90 TEST(LlvmLibcUtilsTest, OffsetFromLastAligned) {
91   EXPECT_EQ(offset_from_last_aligned<16>(forge(0)), I(0));
92   EXPECT_EQ(offset_from_last_aligned<16>(forge(1)), I(1));
93   EXPECT_EQ(offset_from_last_aligned<16>(forge(16)), I(0));
94   EXPECT_EQ(offset_from_last_aligned<16>(forge(15)), I(15));
95   EXPECT_EQ(offset_from_last_aligned<32>(forge(16)), I(16));
96 }
97 
TEST(LlvmLibcUtilsTest,OffsetToNextCacheLine)98 TEST(LlvmLibcUtilsTest, OffsetToNextCacheLine) {
99   EXPECT_GT(LLVM_LIBC_CACHELINE_SIZE, 0);
100   EXPECT_EQ(offset_to_next_cache_line(forge(0)), I(0));
101   EXPECT_EQ(offset_to_next_cache_line(forge(1)),
102             I(LLVM_LIBC_CACHELINE_SIZE - 1));
103   EXPECT_EQ(offset_to_next_cache_line(forge(LLVM_LIBC_CACHELINE_SIZE)), I(0));
104   EXPECT_EQ(offset_to_next_cache_line(forge(LLVM_LIBC_CACHELINE_SIZE - 1)),
105             I(1));
106 }
107 } // namespace __llvm_libc
108