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 
12 TEST(LlvmLibcMemcmpTest, CmpZeroByte) {
13   const char *lhs = "ab";
14   const char *rhs = "yz";
15   EXPECT_EQ(__llvm_libc::memcmp(lhs, rhs, 0), 0);
16 }
17 
18 TEST(LlvmLibcMemcmpTest, LhsRhsAreTheSame) {
19   const char *lhs = "ab";
20   const char *rhs = "ab";
21   EXPECT_EQ(__llvm_libc::memcmp(lhs, rhs, 2), 0);
22 }
23 
24 TEST(LlvmLibcMemcmpTest, LhsBeforeRhsLexically) {
25   const char *lhs = "ab";
26   const char *rhs = "az";
27   EXPECT_LT(__llvm_libc::memcmp(lhs, rhs, 2), 0);
28 }
29 
30 TEST(LlvmLibcMemcmpTest, LhsAfterRhsLexically) {
31   const char *lhs = "az";
32   const char *rhs = "ab";
33   EXPECT_GT(__llvm_libc::memcmp(lhs, rhs, 2), 0);
34 }
35 
36 TEST(LlvmLibcMemcmpTest, Sweep) {
37   static constexpr size_t K_MAX_SIZE = 1024;
38   char lhs[K_MAX_SIZE];
39   char rhs[K_MAX_SIZE];
40 
41   const auto reset = [](char *const ptr) {
42     for (size_t i = 0; i < K_MAX_SIZE; ++i)
43       ptr[i] = 'a';
44   };
45 
46   reset(lhs);
47   reset(rhs);
48   for (size_t i = 0; i < K_MAX_SIZE; ++i)
49     EXPECT_EQ(__llvm_libc::memcmp(lhs, rhs, i), 0);
50 
51   reset(lhs);
52   reset(rhs);
53   for (size_t i = 0; i < K_MAX_SIZE; ++i) {
54     rhs[i] = 'z';
55     EXPECT_LT(__llvm_libc::memcmp(lhs, rhs, K_MAX_SIZE), 0);
56     rhs[i] = 'a';
57   }
58 }
59