| //===- llvm/unittest/Support/CRCTest.cpp - CRC tests ----------------------===// |
| // |
| // 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 |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements unit tests for CRC calculation functions. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/Support/CRC.h" |
| #include "llvm/ADT/StringExtras.h" |
| #include "gtest/gtest.h" |
| |
| using namespace llvm; |
| |
| namespace { |
| |
| TEST(CRCTest, CRC32) { |
| EXPECT_EQ(0x414FA339U, llvm::crc32(arrayRefFromStringRef( |
| "The quick brown fox jumps over the lazy dog"))); |
| |
| // CRC-32/ISO-HDLC test vector |
| // http://reveng.sourceforge.net/crc-catalogue/17plus.htm#crc.cat.crc-32c |
| EXPECT_EQ(0xCBF43926U, llvm::crc32(arrayRefFromStringRef("123456789"))); |
| |
| // Check the CRC-32 of each byte value, exercising all of CRCTable. |
| for (int i = 0; i < 256; i++) { |
| // Compute CRCTable[i] using Hacker's Delight (2nd ed.) Figure 14-7. |
| uint32_t crc = i; |
| for (int j = 7; j >= 0; j--) { |
| uint32_t mask = -(crc & 1); |
| crc = (crc >> 1) ^ (0xEDB88320 & mask); |
| } |
| |
| // CRCTable[i] is the CRC-32 of i without the initial and final bit flips. |
| uint8_t byte = i; |
| EXPECT_EQ(crc, ~llvm::crc32(0xFFFFFFFFU, byte)); |
| } |
| } |
| |
| } // end anonymous namespace |