1 //===-- Unittests for memcmp ----------------------------------------------===//
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/string/memcmp.h"
10 #include "utils/UnitTest/Test.h"
11 #include <cstring>
12 
13 TEST(LlvmLibcMemcmpTest, CmpZeroByte) {
14   const char *lhs = "ab";
15   const char *rhs = "bc";
16   EXPECT_EQ(__llvm_libc::memcmp(lhs, rhs, 0), 0);
17 }
18 
19 TEST(LlvmLibcMemcmpTest, LhsRhsAreTheSame) {
20   const char *lhs = "ab";
21   const char *rhs = "ab";
22   EXPECT_EQ(__llvm_libc::memcmp(lhs, rhs, 2), 0);
23 }
24 
25 TEST(LlvmLibcMemcmpTest, LhsBeforeRhsLexically) {
26   const char *lhs = "ab";
27   const char *rhs = "ac";
28   EXPECT_EQ(__llvm_libc::memcmp(lhs, rhs, 2), -1);
29 }
30 
31 TEST(LlvmLibcMemcmpTest, LhsAfterRhsLexically) {
32   const char *lhs = "ac";
33   const char *rhs = "ab";
34   EXPECT_EQ(__llvm_libc::memcmp(lhs, rhs, 2), 1);
35 }
36 
37 TEST(LlvmLibcMemcmpTest, Sweep) {
38   static constexpr size_t kMaxSize = 1024;
39   char lhs[kMaxSize];
40   char rhs[kMaxSize];
41 
42   memset(lhs, 'a', sizeof(lhs));
43   memset(rhs, 'a', sizeof(rhs));
44   for (int i = 0; i < kMaxSize; ++i)
45     EXPECT_EQ(__llvm_libc::memcmp(lhs, rhs, i), 0);
46 
47   memset(lhs, 'a', sizeof(lhs));
48   memset(rhs, 'a', sizeof(rhs));
49   for (int i = 0; i < kMaxSize; ++i) {
50     rhs[i] = 'b';
51     EXPECT_EQ(__llvm_libc::memcmp(lhs, rhs, kMaxSize), -1);
52     rhs[i] = 'a';
53   }
54 }
55