xref: /aosp_15_r20/external/llvm-libc/test/src/string/memset_test.cpp (revision 71db0c75aadcf003ffe3238005f61d7618a3fead)
1 //===-- Unittests for memset ----------------------------------------------===//
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 "memory_utils/memory_check_utils.h"
10 #include "src/__support/macros/config.h"
11 #include "src/__support/macros/properties/os.h" // LIBC_TARGET_OS_IS_LINUX
12 #include "src/string/memset.h"
13 #include "test/UnitTest/Test.h"
14 
15 #if !defined(LIBC_FULL_BUILD) && defined(LIBC_TARGET_OS_IS_LINUX)
16 #include "memory_utils/protected_pages.h"
17 #endif // !defined(LIBC_FULL_BUILD) && defined(LIBC_TARGET_OS_IS_LINUX)
18 
19 namespace LIBC_NAMESPACE_DECL {
20 
21 // Adapt CheckMemset signature to memset.
Adaptor(cpp::span<char> p1,uint8_t value,size_t size)22 static inline void Adaptor(cpp::span<char> p1, uint8_t value, size_t size) {
23   LIBC_NAMESPACE::memset(p1.begin(), value, size);
24 }
25 
TEST(LlvmLibcMemsetTest,SizeSweep)26 TEST(LlvmLibcMemsetTest, SizeSweep) {
27   static constexpr size_t kMaxSize = 400;
28   Buffer DstBuffer(kMaxSize);
29   for (size_t size = 0; size < kMaxSize; ++size) {
30     const char value = size % 10;
31     auto dst = DstBuffer.span().subspan(0, size);
32     ASSERT_TRUE((CheckMemset<Adaptor>(dst, value, size)));
33   }
34 }
35 
36 #if !defined(LIBC_FULL_BUILD) && defined(LIBC_TARGET_OS_IS_LINUX)
37 
TEST(LlvmLibcMemsetTest,CheckAccess)38 TEST(LlvmLibcMemsetTest, CheckAccess) {
39   static constexpr size_t MAX_SIZE = 1024;
40   LIBC_ASSERT(MAX_SIZE < GetPageSize());
41   ProtectedPages pages;
42   const Page write_buffer = pages.GetPageA().WithAccess(PROT_WRITE);
43   const cpp::array<int, 2> fill_chars = {0, 0x7F};
44   for (int fill_char : fill_chars) {
45     for (size_t size = 0; size < MAX_SIZE; ++size) {
46       // We cross-check the function with two destinations.
47       // - The first of them (bottom) is always page aligned and faults when
48       //   accessing bytes before it.
49       // - The second one (top) is not necessarily aligned and faults when
50       //   accessing bytes after it.
51       uint8_t *destinations[2] = {write_buffer.bottom(size),
52                                   write_buffer.top(size)};
53       for (uint8_t *dst : destinations) {
54         LIBC_NAMESPACE::memset(dst, fill_char, size);
55       }
56     }
57   }
58 }
59 
60 #endif // !defined(LIBC_FULL_BUILD) && defined(LIBC_TARGET_OS_IS_LINUX)
61 
62 } // namespace LIBC_NAMESPACE_DECL
63