1 files changed, 61 insertions, 0 deletions
diff --git a/libc/test/src/strings/bcmp_test.cpp b/libc/test/src/strings/bcmp_test.cpp
new file mode 100644
index 000000000000..794f9a1b8bd9
--- /dev/null
+++ b/libc/test/src/strings/bcmp_test.cpp
@@ -0,0 +1,61 @@
+//===-- Unittests for bcmp ------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/__support/macros/config.h"
+#include "src/strings/bcmp.h"
+#include "test/UnitTest/Test.h"
+#include "test/UnitTest/TestLogger.h"
+#include "test/src/string/memory_utils/memory_check_utils.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+TEST(LlvmLibcBcmpTest, CmpZeroByte) {
+  const char *lhs = "ab";
+  const char *rhs = "bc";
+  ASSERT_EQ(LIBC_NAMESPACE::bcmp(lhs, rhs, 0), 0);
+}
+
+TEST(LlvmLibcBcmpTest, LhsRhsAreTheSame) {
+  const char *lhs = "ab";
+  const char *rhs = "ab";
+  ASSERT_EQ(LIBC_NAMESPACE::bcmp(lhs, rhs, 2), 0);
+}
+
+TEST(LlvmLibcBcmpTest, LhsBeforeRhsLexically) {
+  const char *lhs = "ab";
+  const char *rhs = "ac";
+  ASSERT_NE(LIBC_NAMESPACE::bcmp(lhs, rhs, 2), 0);
+}
+
+TEST(LlvmLibcBcmpTest, LhsAfterRhsLexically) {
+  const char *lhs = "ac";
+  const char *rhs = "ab";
+  ASSERT_NE(LIBC_NAMESPACE::bcmp(lhs, rhs, 2), 0);
+}
+
+// Adapt CheckBcmp signature to bcmp.
+static inline int Adaptor(cpp::span<char> p1, cpp::span<char> p2, size_t size) {
+  return LIBC_NAMESPACE::bcmp(p1.begin(), p2.begin(), size);
+}
+
+TEST(LlvmLibcBcmpTest, SizeSweep) {
+  static constexpr size_t kMaxSize = 400;
+  Buffer Buffer1(kMaxSize);
+  Buffer Buffer2(kMaxSize);
+  Randomize(Buffer1.span());
+  for (size_t size = 0; size < kMaxSize; ++size) {
+    auto span1 = Buffer1.span().subspan(0, size);
+    auto span2 = Buffer2.span().subspan(0, size);
+    const bool OK = CheckBcmp<Adaptor>(span1, span2, size);
+    if (!OK)
+      testing::tlog << "Failed at size=" << size << '\n';
+    ASSERT_TRUE(OK);
+  }
+}
+
+} // namespace LIBC_NAMESPACE_DECL