rocFFT

rocFFT is a software library for computing fast Fourier transforms (FFTs) written in the HIP programming language. It's part of AMD's software ecosystem based on ROCm. The rocFFT library can be used with AMD and NVIDIA GPUs.

Documentation

[!NOTE] The published rocFFT documentation is available at rocFFT in an organized, easy-to-read format, with search and a table of contents. The documentation source files reside in the rocFFT/docs folder of this repository. As with all ROCm projects, the documentation is open source. For more information, see Contribute to ROCm documentation.

To build our documentation locally, use the following code:

cd docs

pip3 install -r sphinx/requirements.txt

python3 -m sphinx -T -E -b html -d _build/doctrees -D language=en . _build/html

Build and install

You can install rocFFT using pre-built packages or building from source.

• Installing pre-built packages:

  1. Download the pre-built packages from the ROCm package servers or use the GitHub releases tab to download the source (this may give you a more recent version than the pre-built packages).

  2. Run: sudo apt update && sudo apt install rocfft

• Building from source:

  rocFFT is compiled with AMD's clang++ and uses CMake. You can specify several options to customize your build. The following commands build a shared library for supported AMD GPUs:

  mkdir build && cd build
  cmake -DCMAKE_CXX_COMPILER=amdclang++ -DCMAKE_C_COMPILER=amdclang ..
  make -j

  You can compile a static library using the -DBUILD_SHARED_LIBS=off option.

  With rocFFT, you can use indirect function calls by default; this requires ROCm 4.3 or higher. You can use -DROCFFT_CALLBACKS_ENABLED=off with CMake to prevent these calls on older ROCm compilers. Note that with this configuration, callbacks won't work correctly.

  rocFFT includes the following clients:

  • rocfft-bench: Runs general transforms and is useful for performance analysis
  • rocfft-test: Runs various regression tests
  • Various small samples

  Client	CMake option	Dependencies
  rocfft-bench	-DBUILD_CLIENTS_BENCH=on	hipRAND
  rocfft-test	-DBUILD_CLIENTS_TESTS=on	FFTW (Fastest Fourier Transform in the West), GoogleTest, hipRAND
  samples	-DBUILD_CLIENTS_SAMPLES=on	FFTW

  Clients are not built by default. To build them, use -DBUILD_CLIENTS=on. The build process downloads and builds GoogleTest and FFTW if they are not already installed.

  Clients can be built separately from the main library. For example, you can build all the clients with an existing rocFFT library by invoking CMake from within the rocFFT-src/clients folder:

  mkdir build && cd build
  cmake -DCMAKE_CXX_COMPILER=amdclang++ -DCMAKE_C_COMPILER=amdclang_PREFIX_PATH=/path/to/rocFFT-lib ..
  make -j

  To install client dependencies on Ubuntu, run:

  sudo apt install libgtest-dev libfftw3-dev

  We use version 1.11 of GoogleTest.

Examples

A summary of the latest functionality and workflow to compute an FFT with rocFFT is available on the rocFFT documentation portal.

You can find additional examples in the clients/samples subdirectory.

Support

You can report bugs and feature requests through the GitHub issue tracker.

Contribute

If you want to contribute to rocFFT, you must follow our contribution guidelines.