1 /*
2 * Copyright (C) 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <stdint.h>
18 #include <stdlib.h>
19 #include <string.h>
20 #include <sys/mman.h>
21 #include <sys/types.h>
22
23 #include <memory>
24
25 #include <cutils/memory.h>
26 #include <gtest/gtest.h>
27
28 #define FENCEPOST_LENGTH 8
29
30 #define MAX_TEST_SIZE (64*1024)
31 // Choose values that have no repeating byte values.
32 #define MEMSET16_PATTERN 0xb139
33 #define MEMSET32_PATTERN 0x48193a27
34
35 enum test_e {
36 MEMSET16 = 0,
37 MEMSET32,
38 };
39
40 static int g_memset16_aligns[][2] = {
41 { 2, 0 },
42 { 4, 0 },
43 { 8, 0 },
44 { 16, 0 },
45 { 32, 0 },
46 { 64, 0 },
47 { 128, 0 },
48
49 { 4, 2 },
50
51 { 8, 2 },
52 { 8, 4 },
53 { 8, 6 },
54
55 { 128, 2 },
56 { 128, 4 },
57 { 128, 6 },
58 { 128, 8 },
59 { 128, 10 },
60 { 128, 12 },
61 { 128, 14 },
62 { 128, 16 },
63 };
64
65 static int g_memset32_aligns[][2] = {
66 { 4, 0 },
67 { 8, 0 },
68 { 16, 0 },
69 { 32, 0 },
70 { 64, 0 },
71 { 128, 0 },
72
73 { 8, 4 },
74
75 { 128, 4 },
76 { 128, 8 },
77 { 128, 12 },
78 { 128, 16 },
79 };
80
GetIncrement(size_t len,size_t min_incr)81 static size_t GetIncrement(size_t len, size_t min_incr) {
82 if (len >= 4096) {
83 return 1024;
84 } else if (len >= 1024) {
85 return 256;
86 }
87 return min_incr;
88 }
89
90 // Return a pointer into the current buffer with the specified alignment.
GetAlignedPtr(void * orig_ptr,int alignment,int or_mask)91 static void *GetAlignedPtr(void *orig_ptr, int alignment, int or_mask) {
92 uint64_t ptr = reinterpret_cast<uint64_t>(orig_ptr);
93 if (alignment > 0) {
94 // When setting the alignment, set it to exactly the alignment chosen.
95 // The pointer returned will be guaranteed not to be aligned to anything
96 // more than that.
97 ptr += alignment - (ptr & (alignment - 1));
98 ptr |= alignment | or_mask;
99 }
100
101 return reinterpret_cast<void*>(ptr);
102 }
103
SetFencepost(uint8_t * buffer)104 static void SetFencepost(uint8_t *buffer) {
105 for (int i = 0; i < FENCEPOST_LENGTH; i += 2) {
106 buffer[i] = 0xde;
107 buffer[i+1] = 0xad;
108 }
109 }
110
VerifyFencepost(uint8_t * buffer)111 static void VerifyFencepost(uint8_t *buffer) {
112 for (int i = 0; i < FENCEPOST_LENGTH; i += 2) {
113 if (buffer[i] != 0xde || buffer[i+1] != 0xad) {
114 uint8_t expected_value;
115 if (buffer[i] == 0xde) {
116 i++;
117 expected_value = 0xad;
118 } else {
119 expected_value = 0xde;
120 }
121 ASSERT_EQ(expected_value, buffer[i]);
122 }
123 }
124 }
125
RunMemsetTests(test_e test_type,uint32_t value,int align[][2],size_t num_aligns)126 void RunMemsetTests(test_e test_type, uint32_t value, int align[][2], size_t num_aligns) {
127 size_t min_incr = 4;
128 if (test_type == MEMSET16) {
129 min_incr = 2;
130 value |= value << 16;
131 }
132 std::unique_ptr<uint32_t[]> expected_buf(new uint32_t[MAX_TEST_SIZE/sizeof(uint32_t)]);
133 for (size_t i = 0; i < MAX_TEST_SIZE/sizeof(uint32_t); i++) {
134 expected_buf[i] = value;
135 }
136
137 // Allocate one large buffer with lots of extra space so that we can
138 // guarantee that all possible alignments will fit.
139 std::unique_ptr<uint8_t[]> buf(new uint8_t[3*MAX_TEST_SIZE]);
140 uint8_t *buf_align;
141 for (size_t i = 0; i < num_aligns; i++) {
142 size_t incr = min_incr;
143 for (size_t len = incr; len <= MAX_TEST_SIZE; len += incr) {
144 incr = GetIncrement(len, min_incr);
145
146 buf_align = reinterpret_cast<uint8_t*>(GetAlignedPtr(
147 buf.get()+FENCEPOST_LENGTH, align[i][0], align[i][1]));
148
149 SetFencepost(&buf_align[-FENCEPOST_LENGTH]);
150 SetFencepost(&buf_align[len]);
151
152 memset(buf_align, 0xff, len);
153 if (test_type == MEMSET16) {
154 android_memset16(reinterpret_cast<uint16_t*>(buf_align), value, len);
155 } else {
156 android_memset32(reinterpret_cast<uint32_t*>(buf_align), value, len);
157 }
158 ASSERT_EQ(0, memcmp(expected_buf.get(), buf_align, len))
159 << "Failed size " << len << " align " << align[i][0] << " " << align[i][1] << "\n";
160
161 VerifyFencepost(&buf_align[-FENCEPOST_LENGTH]);
162 VerifyFencepost(&buf_align[len]);
163 }
164 }
165 }
166
TEST(libcutils,android_memset16_non_zero)167 TEST(libcutils, android_memset16_non_zero) {
168 RunMemsetTests(MEMSET16, MEMSET16_PATTERN, g_memset16_aligns, sizeof(g_memset16_aligns)/sizeof(int[2]));
169 }
170
TEST(libcutils,android_memset16_zero)171 TEST(libcutils, android_memset16_zero) {
172 RunMemsetTests(MEMSET16, 0, g_memset16_aligns, sizeof(g_memset16_aligns)/sizeof(int[2]));
173 }
174
TEST(libcutils,android_memset32_non_zero)175 TEST(libcutils, android_memset32_non_zero) {
176 RunMemsetTests(MEMSET32, MEMSET32_PATTERN, g_memset32_aligns, sizeof(g_memset32_aligns)/sizeof(int[2]));
177 }
178
TEST(libcutils,android_memset32_zero)179 TEST(libcutils, android_memset32_zero) {
180 RunMemsetTests(MEMSET32, 0, g_memset32_aligns, sizeof(g_memset32_aligns)/sizeof(int[2]));
181 }
182