/*
* Copyright (c) Meta Platforms, Inc. and affiliates.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <folly/hash/Checksum.h>
#include <boost/crc.hpp>
#include <folly/Benchmark.h>
#include <folly/Random.h>
#include <folly/external/fast-crc32/avx512_crc32c_v8s3x4.h>
#include <folly/external/fast-crc32/sse_crc32c_v8s3x3.h>
#include <folly/hash/Hash.h>
#include <folly/hash/detail/ChecksumDetail.h>
#include <folly/portability/GFlags.h>
#include <folly/portability/GTest.h>
namespace {
const unsigned int BUFFER_SIZE = 512 * 1024 * sizeof(uint64_t);
uint8_t buffer[BUFFER_SIZE];
struct ExpectedResult {
size_t offset;
size_t length;
uint32_t crc32c;
};
ExpectedResult expectedResults[] = {
// Zero-byte input
{0, 0, ~0U},
// Small aligned inputs to test special cases in SIMD implementations
{8, 1, 1543413366},
{8, 2, 523493126},
{8, 3, 1560427360},
{8, 4, 3422504776},
{8, 5, 447841138},
{8, 6, 3910050499},
{8, 7, 3346241981},
// Small unaligned inputs
{9, 1, 3855826643},
{10, 2, 560880875},
{11, 3, 1479707779},
{12, 4, 2237687071},
{13, 5, 4063855784},
{14, 6, 2553454047},
{15, 7, 1349220140},
// Larger inputs to test leftover chunks at the end of aligned blocks
{8, 8, 627613930},
{8, 9, 2105929409},
{8, 10, 2447068514},
{8, 11, 863807079},
{8, 12, 292050879},
{8, 13, 1411837737},
{8, 14, 2614515001},
{8, 15, 3579076296},
{8, 16, 2897079161},
{8, 17, 675168386},
// Much larger inputs
{0, BUFFER_SIZE, 2096790750},
{1, BUFFER_SIZE / 2, 3854797577},
};
void testCRC32C(
std::function<uint32_t(const uint8_t*, size_t, uint32_t)> impl) {
for (auto expected : expectedResults) {
uint32_t result = impl(buffer + expected.offset, expected.length, ~0U);
EXPECT_EQ(expected.crc32c, result);
}
}
void testCRC32CContinuation(
std::function<uint32_t(const uint8_t*, size_t, uint32_t)> impl) {
for (auto expected : expectedResults) {
size_t partialLength = expected.length / 2;
uint32_t partialChecksum =
impl(buffer + expected.offset, partialLength, ~0U);
uint32_t result = impl(
buffer + expected.offset + partialLength,
expected.length - partialLength,
partialChecksum);
EXPECT_EQ(expected.crc32c, result);
}
}
void testMatchesBoost32Type() {
for (auto expected : expectedResults) {
boost::crc_32_type result;
result.process_bytes(buffer + expected.offset, expected.length);
const uint32_t boostResult = result.checksum();
const uint32_t follyResult =
folly::crc32_type(buffer + expected.offset, expected.length);
EXPECT_EQ(follyResult, boostResult);
}
}
} // namespace
TEST(Checksum, crc32cSoftware) {
testCRC32C(folly::detail::crc32c_sw);
}
TEST(Checksum, crc32cContinuationSoftware) {
testCRC32CContinuation(folly::detail::crc32c_sw);
}
TEST(Checksum, crc32cHardware) {
if (folly::detail::crc32c_hw_supported()) {
testCRC32C(folly::detail::crc32c_hw);
} else {
LOG(WARNING) << "skipping hardware-accelerated CRC-32C tests"
<< " (not supported on this CPU)";
}
}
TEST(Checksum, crc32cHardwareEq) {
if (folly::detail::crc32c_hw_supported()) {
for (int i = 0; i < 1000; i++) {
auto sw = folly::detail::crc32c_sw(buffer, i, 0);
auto hw = folly::detail::crc32c_hw(buffer, i, 0);
EXPECT_EQ(sw, hw);
}
} else {
LOG(WARNING) << "skipping hardware-accelerated CRC-32C tests"
<< " (not supported on this CPU)";
}
}
TEST(Checksum, crc32cContinuationHardware) {
if (folly::detail::crc32c_hw_supported()) {
testCRC32CContinuation(folly::detail::crc32c_hw);
} else {
LOG(WARNING) << "skipping hardware-accelerated CRC-32C tests"
<< " (not supported on this CPU)";
}
}
TEST(Checksum, crc32cHardwareSse42) {
if (folly::detail::crc32c_hw_supported()) {
testCRC32C(folly::detail::sse_crc32c_v8s3x3);
} else {
LOG(WARNING) << "skipping SSE4.2 hardware-accelerated CRC-32C tests"
<< " (not supported on this CPU)";
}
}
TEST(Checksum, crc32cHardwareEqSse42) {
if (folly::detail::crc32c_hw_supported()) {
for (size_t i = 0; i < 1000; i++) {
auto sw = folly::detail::crc32c_sw(buffer, i, 0);
auto hw = folly::detail::sse_crc32c_v8s3x3(buffer, i, 0);
ASSERT_EQ(sw, hw);
}
} else {
LOG(WARNING) << "skipping SSE4.2 hardware-accelerated CRC-32C tests"
<< " (not supported on this CPU)";
}
}
TEST(Checksum, crc32cContinuationHardwareSse42) {
if (folly::detail::crc32c_hw_supported()) {
testCRC32CContinuation(folly::detail::sse_crc32c_v8s3x3);
} else {
LOG(WARNING) << "skipping SSE4.2 hardware-accelerated CRC-32C tests"
<< " (not supported on this CPU)";
}
}
TEST(Checksum, crc32cHardwareAvx512) {
if (folly::detail::crc32c_hw_supported_avx512()) {
testCRC32C(folly::detail::avx512_crc32c_v8s3x4);
} else {
LOG(WARNING) << "skipping AVX512 hardware-accelerated CRC-32C tests"
<< " (not supported on this CPU)";
}
}
TEST(Checksum, crc32cHardwareEqAvx512) {
if (folly::detail::crc32c_hw_supported_avx512()) {
for (size_t i = 0; i < 1000; i++) {
auto sw = folly::detail::crc32c_sw(buffer, i, 0);
auto hw = folly::detail::avx512_crc32c_v8s3x4(buffer, i, 0);
ASSERT_EQ(sw, hw);
}
} else {
LOG(WARNING) << "skipping AVX512 hardware-accelerated CRC-32C tests"
<< " (not supported on this CPU)";
}
}
TEST(Checksum, crc32cContinuationHardwareAvx512) {
if (folly::detail::crc32c_hw_supported_avx512()) {
testCRC32CContinuation(folly::detail::avx512_crc32c_v8s3x4);
} else {
LOG(WARNING) << "skipping AVX512 hardware-accelerated CRC-32C tests"
<< " (not supported on this CPU)";
}
}
// Test on very large buffer inputs to attempt to sanity check 32-bit
// overflow problems on 64-bit platforms.
#ifdef __LP64__
TEST(Checksum, crc32clargeBuffers) {
constexpr size_t kLargeBufSz = 5ull * 1024 * 1024 * 1024; // 5GiB
auto buf = std::make_unique<uint8_t[]>(kLargeBufSz); // 5GiB
auto* bufp = buf.get();
// Fill with non-zero pattern.
memset(bufp, 0x2e, kLargeBufSz);
constexpr uint32_t kCrc = 2860399007;
if (folly::detail::crc32c_hw_supported()) {
auto crcSse42 = folly::detail::sse_crc32c_v8s3x3(bufp, kLargeBufSz, ~0);
ASSERT_EQ(kCrc, crcSse42);
auto crcHw = folly::detail::crc32c_hw(bufp, kLargeBufSz, ~0);
ASSERT_EQ(kCrc, crcHw);
}
if (folly::detail::crc32c_hw_supported_avx512()) {
auto crcAvx = folly::detail::avx512_crc32c_v8s3x4(bufp, kLargeBufSz, ~0);
ASSERT_EQ(kCrc, crcAvx);
}
}
#endif
TEST(Checksum, crc32cAutodetect) {
testCRC32C(folly::crc32c);
}
TEST(Checksum, crc32cContinuationAutodetect) {
testCRC32CContinuation(folly::crc32c);
}
TEST(Checksum, crc32) {
if (folly::detail::crc32c_hw_supported()) {
// Just check that sw and hw match
for (auto expected : expectedResults) {
uint32_t sw_res =
folly::detail::crc32_sw(buffer + expected.offset, expected.length, 0);
uint32_t hw_res =
folly::detail::crc32_hw(buffer + expected.offset, expected.length, 0);
EXPECT_EQ(sw_res, hw_res);
}
} else {
LOG(WARNING) << "skipping hardware-accelerated CRC-32 tests"
<< " (not supported on this CPU)";
}
}
TEST(Checksum, crc32Continuation) {
if (folly::detail::crc32c_hw_supported()) {
// Just check that sw and hw match
for (auto expected : expectedResults) {
auto halflen = expected.length / 2;
uint32_t sw_res =
folly::detail::crc32_sw(buffer + expected.offset, halflen, 0);
sw_res = folly::detail::crc32_sw(
buffer + expected.offset + halflen, halflen, sw_res);
uint32_t hw_res =
folly::detail::crc32_hw(buffer + expected.offset, halflen, 0);
hw_res = folly::detail::crc32_hw(
buffer + expected.offset + halflen, halflen, hw_res);
EXPECT_EQ(sw_res, hw_res);
uint32_t sw_res2 =
folly::detail::crc32_sw(buffer + expected.offset, halflen * 2, 0);
EXPECT_EQ(sw_res, sw_res2);
uint32_t hw_res2 =
folly::detail::crc32_hw(buffer + expected.offset, halflen * 2, 0);
EXPECT_EQ(hw_res, hw_res2);
}
} else {
LOG(WARNING) << "skipping hardware-accelerated CRC-32 tests"
<< " (not supported on this CPU)";
}
}
TEST(Checksum, crc32Type) {
// Test that crc32_type matches boost::crc_32_type
testMatchesBoost32Type();
}
TEST(Checksum, crc32Combine) {
for (size_t totlen = 1024; totlen < BUFFER_SIZE; totlen += BUFFER_SIZE / 8) {
auto mid = folly::Random::rand64(0, totlen);
auto crc1 = folly::crc32(&buffer[0], mid, 0);
auto crc2 = folly::crc32(&buffer[mid], totlen - mid, 0);
auto crcfull = folly::crc32(&buffer[0], totlen, 0);
auto combined = folly::crc32_combine(crc1, crc2, totlen - mid);
EXPECT_EQ(combined, crcfull);
}
}
TEST(Checksum, crc32cCombine) {
for (size_t totlen = 1024; totlen < BUFFER_SIZE; totlen += BUFFER_SIZE / 8) {
auto mid = folly::Random::rand64(0, totlen);
auto crc1 = folly::crc32c(&buffer[0], mid, 0);
auto crc2 = folly::crc32c(&buffer[mid], totlen - mid, 0);
auto crcfull = folly::crc32c(&buffer[0], totlen, 0);
auto combined = folly::crc32c_combine(crc1, crc2, totlen - mid);
EXPECT_EQ(combined, crcfull);
}
}
void benchmarkHardwareCRC32C(unsigned long iters, size_t blockSize) {
if (folly::detail::crc32c_hw_supported()) {
uint32_t checksum;
for (unsigned long i = 0; i < iters; i++) {
checksum = folly::detail::crc32c_hw(buffer, blockSize);
folly::doNotOptimizeAway(checksum);
}
} else {
LOG(WARNING) << "skipping hardware-accelerated CRC-32C benchmarks"
<< " (not supported on this CPU)";
}
}
void benchmarkSoftwareCRC32C(unsigned long iters, size_t blockSize) {
uint32_t checksum;
for (unsigned long i = 0; i < iters; i++) {
checksum = folly::detail::crc32c_sw(buffer, blockSize);
folly::doNotOptimizeAway(checksum);
}
}
void benchmarkHardwareCRC32(unsigned long iters, size_t blockSize) {
if (folly::detail::crc32_hw_supported()) {
uint32_t checksum;
for (unsigned long i = 0; i < iters; i++) {
checksum = folly::detail::crc32_hw(buffer, blockSize);
folly::doNotOptimizeAway(checksum);
}
} else {
LOG(WARNING) << "skipping hardware-accelerated CRC-32 benchmarks"
<< " (not supported on this CPU)";
}
}
void benchmarkSoftwareCRC32(unsigned long iters, size_t blockSize) {
uint32_t checksum;
for (unsigned long i = 0; i < iters; i++) {
checksum = folly::detail::crc32_sw(buffer, blockSize);
folly::doNotOptimizeAway(checksum);
}
}
void benchmarkCombineHardwareCrc32(unsigned long iters, size_t blockSize) {
// Arbitrarily chosen checksums
uint32_t checksum1 = 0xEDB88320;
uint32_t checksum2 = 0x82F63B78;
uint32_t result;
for (unsigned long i = 0; i < iters; i++) {
result = folly::crc32_combine(checksum1, checksum2, blockSize);
folly::doNotOptimizeAway(result);
}
}
void benchmarkCombineSoftwareLinear(unsigned long iters, size_t blockSize) {
// Arbitrarily chosen checksums
std::vector<uint8_t> zbuffer;
zbuffer.reserve(blockSize);
memset(zbuffer.data(), 0, blockSize);
uint32_t checksum1 = 0xEDB88320;
uint32_t checksum2 = 0x82F63B78;
uint32_t result;
for (unsigned long i = 0; i < iters; i++) {
result = folly::crc32c(zbuffer.data(), blockSize, checksum1);
result ^= checksum2;
folly::doNotOptimizeAway(result);
}
}
void benchmarkCombineHardwareCrc32c(unsigned long iters, size_t blockSize) {
// Arbitrarily chosen checksums
uint32_t checksum1 = 0xEDB88320;
uint32_t checksum2 = 0x82F63B78;
uint32_t result;
for (unsigned long i = 0; i < iters; i++) {
result = folly::crc32c_combine(checksum1, checksum2, blockSize);
folly::doNotOptimizeAway(result);
}
}
// This test fits easily in the L1 cache on modern server processors,
// and thus it mainly measures the speed of the checksum computation.
BENCHMARK(crc32c_hardware_1KB_block, iters) {
benchmarkHardwareCRC32C(iters, 1024);
}
BENCHMARK(crc32c_software_1KB_block, iters) {
benchmarkSoftwareCRC32C(iters, 1024);
}
BENCHMARK(crc32_hardware_1KB_block, iters) {
benchmarkHardwareCRC32(iters, 1024);
}
BENCHMARK(crc32_software_1KB_block, iters) {
benchmarkSoftwareCRC32(iters, 1024);
}
BENCHMARK_DRAW_LINE();
// This test is too big for the L1 cache but fits in L2
BENCHMARK(crc32c_hardware_64KB_block, iters) {
benchmarkHardwareCRC32C(iters, 64 * 1024);
}
BENCHMARK(crc32c_software_64KB_block, iters) {
benchmarkSoftwareCRC32C(iters, 64 * 1024);
}
BENCHMARK(crc32_hardware_64KB_block, iters) {
benchmarkHardwareCRC32(iters, 64 * 1024);
}
BENCHMARK(crc32_software_64KB_block, iters) {
benchmarkSoftwareCRC32(iters, 64 * 1024);
}
BENCHMARK_DRAW_LINE();
// This test is too big for the L2 cache but fits in L3
BENCHMARK(crc32c_hardware_512KB_block, iters) {
benchmarkHardwareCRC32C(iters, 512 * 1024);
}
BENCHMARK(crc32c_software_512KB_block, iters) {
benchmarkSoftwareCRC32C(iters, 512 * 1024);
}
BENCHMARK(crc32_hardware_512KB_block, iters) {
benchmarkHardwareCRC32(iters, 512 * 1024);
}
BENCHMARK(crc32_software_512KB_block, iters) {
benchmarkSoftwareCRC32(iters, 512 * 1024);
}
BENCHMARK_DRAW_LINE();
BENCHMARK(crc32_combine_linear_512KB_block, iters) {
benchmarkCombineSoftwareLinear(iters, 512 * 1024);
}
BENCHMARK(crc32_combine_512KB_block, iters) {
benchmarkCombineHardwareCrc32(iters, 512 * 1024);
}
BENCHMARK(crc32c_combine_512KB_block, iters) {
benchmarkCombineHardwareCrc32c(iters, 512 * 1024);
}
int main(int argc, char** argv) {
testing::InitGoogleTest(&argc, argv);
gflags::ParseCommandLineFlags(&argc, &argv, true);
// Populate a buffer with a deterministic pattern
// on which to compute checksums
const uint8_t* src = buffer;
uint64_t* dst = (uint64_t*)buffer;
const uint64_t* end = (const uint64_t*)(buffer + sizeof(buffer));
*dst++ = 0;
while (dst < end) {
*dst++ = folly::hash::fnv64_buf((const char*)src, sizeof(uint64_t));
src += sizeof(uint64_t);
}
auto ret = RUN_ALL_TESTS();
if (!ret && FLAGS_benchmark) {
folly::runBenchmarks();
}
return ret;
}
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