tinycrc32

Introduction

This is a small header-only library that contains both hadware-accelerated and not hardware-accelerated implementations of the crc32c algorithm. Features include:

• Everything in single header file that has around 250 lines of actual code
• Three different levels of data throughput ranging from 8.549 to 0.144 cycles per byte

Please note that the Castagnoli version of the CRC32 algorithm here uses the 0x1EDC6F41 polynomial and not the standard one i.e 0x04C11DB7. For detailed documentation please refer to the pdfs in the docs directory and the source file itself.

Quickstart

In the header file there is basically just one function one wants to call as depending on the compile flags a different implementation will be used for that function. For example the following main.cpp file

#include <cstring>
#include <iostream>

#include "tinycrc32.h"

int main() {
  std::size_t n = 1031 
  uint8_t *data = new uint8_t[n];
  std::memset(data, 7, n);

  std::cout << crc32c(data, n) << std::endl;

  delete[] data;
  return 0;
}

can be compiled in three different ways. First the default version, which does not have any hardware acceleration enabled.

g++ -std=c++11 ./main.cpp -o main

The second version with SSE42 hardware acceleration can be compiled by adding the -DENABLE_SSE42 compiler flag.

g++ -std=c++11 -DENABLE_SSE42 -o main

Laslty to enable the pipling of the CRC32 instruction using the PCLMULQDQ instructions the -DENABLE_PCLMULQDQ flag must be passed to the compiler.

g++ -std=c++11 -DENABLE_SSE42 -DENABLE_PCLMULQDQ -o main

Testing & Benchmarking

The test and benchmark executable can be build by running make test and make benchmark respectively. It is important to note though that google-test is required for the test executable and google-benchmark for the benchmark executable. To enable hardware acceleration in the test and benchmark executable please check the makefile.