QuadIron

The QuadIron library is a C++ library, written in C++14, that offers a streaming API to use the different flavors of NTT-based erasure codes.

The library focuses primarily on high fragmentation i.e. n >> k.

It includes general modular arithmetic routines, algorithms for manipulating rings of integers modulo n, finite fields (including binary, prime and (non binary) extension fields), polynomial operations, implementations of different flavors of discrete Fourier transforms and forward error correction (FEC) codes algorithms.

The library also includes an abstraction for writing systematic and non-systematic codes, although for applications requiring high fragmentation systematic codes are not necessarily useful.

Build from source

Build

mkdir build
cd build
cmake -G 'Unix Makefiles' ..
make

WARNING: If you are compiling the code with Clang, don't use a 4.X version: there is a bug that affects SIMD code in QuadIron.

Targets

• doc: build the documentation using Doxygen
• bench: build the QuadIron benchmark (build mode "Release" is recommended)
• shared: build the QuadIron shared library
• static: build the QuadIron static library
• unit_tests: build the unit tests.
• check: run the test suite
• benchmark: run the QuadIron benchmark (build mode "Release" is recommended)
• package: generate a binary installer
• package_source: generate a source installer (a tarball with the sources)
• install: install the library in CMAKE_INSTALL_PREFIX.
• uninstall: uninstall the library.

Code coverage

By default the code coverage is not enabled.

To generate the code coverage reports:

1. set the option ENABLE_COVERAGE to ON.
2. recompile with make.
3. run the tests with make check.
4. extract coverage data with make gcov.
5. generate a report with make lcov.
6. open the report in ${CMAKE_BINARY_DIR}/lcov/html/all_targets.

Note that, even though code coverage is supported by both Clang and GCC, result with GCC seems more reliable (not surprising as we are using gcov).

SIMD vectorization

QuadIron can be accelerated using SIMD vectorization. This is controlled by the USE_SIMD parameter, that can have one of the following values:

• OFF (default value): no SIMD vectorization (except the one done by the compiler)
• ON: select the best SIMD instructions set supported by QuadIron and the machine
• SSE: use SSE4.1 SIMD instructions
• AVX: use AVX2 SIMD instructions