xref: /aosp_15_r20/external/llvm-libc/test/src/string/memmove_test.cpp (revision 71db0c75aadcf003ffe3238005f61d7618a3fead)
1 //===-- Unittests for memmove ---------------------------------------------===//
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/macros/config.h"
10 #include "src/string/memmove.h"
11 
12 #include "memory_utils/memory_check_utils.h"
13 #include "src/__support/CPP/span.h"
14 #include "test/UnitTest/MemoryMatcher.h"
15 #include "test/UnitTest/Test.h"
16 
17 using LIBC_NAMESPACE::cpp::array;
18 using LIBC_NAMESPACE::cpp::span;
19 
20 namespace LIBC_NAMESPACE_DECL {
21 
TEST(LlvmLibcMemmoveTest,MoveZeroByte)22 TEST(LlvmLibcMemmoveTest, MoveZeroByte) {
23   char Buffer[] = {'a', 'b', 'y', 'z'};
24   const char Expected[] = {'a', 'b', 'y', 'z'};
25   void *const Dst = Buffer;
26   void *const Ret = LIBC_NAMESPACE::memmove(Dst, Buffer + 2, 0);
27   EXPECT_EQ(Ret, Dst);
28   ASSERT_MEM_EQ(Buffer, testing::MemoryView(Expected));
29 }
30 
TEST(LlvmLibcMemmoveTest,DstAndSrcPointToSameAddress)31 TEST(LlvmLibcMemmoveTest, DstAndSrcPointToSameAddress) {
32   char Buffer[] = {'a', 'b'};
33   const char Expected[] = {'a', 'b'};
34   void *const Dst = Buffer;
35   void *const Ret = LIBC_NAMESPACE::memmove(Dst, Buffer, 1);
36   EXPECT_EQ(Ret, Dst);
37   ASSERT_MEM_EQ(Buffer, testing::MemoryView(Expected));
38 }
39 
TEST(LlvmLibcMemmoveTest,DstStartsBeforeSrc)40 TEST(LlvmLibcMemmoveTest, DstStartsBeforeSrc) {
41   // Set boundary at beginning and end for not overstepping when
42   // copy forward or backward.
43   char Buffer[] = {'z', 'a', 'b', 'c', 'z'};
44   const char Expected[] = {'z', 'b', 'c', 'c', 'z'};
45   void *const Dst = Buffer + 1;
46   void *const Ret = LIBC_NAMESPACE::memmove(Dst, Buffer + 2, 2);
47   EXPECT_EQ(Ret, Dst);
48   ASSERT_MEM_EQ(Buffer, testing::MemoryView(Expected));
49 }
50 
TEST(LlvmLibcMemmoveTest,DstStartsAfterSrc)51 TEST(LlvmLibcMemmoveTest, DstStartsAfterSrc) {
52   char Buffer[] = {'z', 'a', 'b', 'c', 'z'};
53   const char Expected[] = {'z', 'a', 'a', 'b', 'z'};
54   void *const Dst = Buffer + 2;
55   void *const Ret = LIBC_NAMESPACE::memmove(Dst, Buffer + 1, 2);
56   EXPECT_EQ(Ret, Dst);
57   ASSERT_MEM_EQ(Buffer, testing::MemoryView(Expected));
58 }
59 
60 // e.g. `Dst` follow `src`.
61 // str: [abcdefghij]
62 //      [__src_____]
63 //      [_____Dst__]
TEST(LlvmLibcMemmoveTest,SrcFollowDst)64 TEST(LlvmLibcMemmoveTest, SrcFollowDst) {
65   char Buffer[] = {'z', 'a', 'b', 'z'};
66   const char Expected[] = {'z', 'b', 'b', 'z'};
67   void *const Dst = Buffer + 1;
68   void *const Ret = LIBC_NAMESPACE::memmove(Dst, Buffer + 2, 1);
69   EXPECT_EQ(Ret, Dst);
70   ASSERT_MEM_EQ(Buffer, testing::MemoryView(Expected));
71 }
72 
TEST(LlvmLibcMemmoveTest,DstFollowSrc)73 TEST(LlvmLibcMemmoveTest, DstFollowSrc) {
74   char Buffer[] = {'z', 'a', 'b', 'z'};
75   const char Expected[] = {'z', 'a', 'a', 'z'};
76   void *const Dst = Buffer + 2;
77   void *const Ret = LIBC_NAMESPACE::memmove(Dst, Buffer + 1, 1);
78   EXPECT_EQ(Ret, Dst);
79   ASSERT_MEM_EQ(Buffer, testing::MemoryView(Expected));
80 }
81 
82 // Adapt CheckMemmove signature to op implementation signatures.
Adaptor(cpp::span<char> dst,cpp::span<char> src,size_t size)83 static inline void Adaptor(cpp::span<char> dst, cpp::span<char> src,
84                            size_t size) {
85   LIBC_NAMESPACE::memmove(dst.begin(), src.begin(), size);
86 }
87 
TEST(LlvmLibcMemmoveTest,SizeSweep)88 TEST(LlvmLibcMemmoveTest, SizeSweep) {
89   static constexpr int kMaxSize = 400;
90   static constexpr int kDenseOverlap = 15;
91   using LargeBuffer = array<char, 2 * kMaxSize + 1>;
92   LargeBuffer Buffer;
93   Randomize(Buffer);
94   for (int Size = 0; Size < kMaxSize; ++Size)
95     for (int Overlap = -1; Overlap < Size;) {
96       ASSERT_TRUE(CheckMemmove<Adaptor>(Buffer, Size, Overlap));
97       // Prevent quadratic behavior by skipping offset above kDenseOverlap.
98       if (Overlap > kDenseOverlap)
99         Overlap *= 2;
100       else
101         ++Overlap;
102     }
103 }
104 
105 } // namespace LIBC_NAMESPACE_DECL
106