FFTW3

This is a fork of the FFTW3 for the Armv8-A 64-bit architecture (AArch64) with 512-bit Scalable Vector Extension (SVE) support.

See the FFTW home page for more information.

Prerequisites

• Fujitsu Fortran Compiler and Fujitsu C/C++ Compiler
• GNU automake 1.16.1 or higher
• GNU Autoconf 2.69 or higher
• GNU libtool 2.4.6 or higher
• GNU Texinfo 6.7 or higher

Installation

Download the source code

• Clone this repository.

$ git clone https://github.com/fujitsu/fftw3.git

Generate configure scripts

• Run autoreconf.

$ cd fftw3
$ touch ChangeLog
$ autoreconf --verbose --install --symlink --force

Building FFTW3

Notice

• To create a library for fortran, specify --enable-linkfortran at configure, if the compiler option -Nclang is specified in the environment variable for compile command or in the compilation profile file.

Single precision

• Native compilation using Fujitsu compiler (AArch64 target).

$ ./configure                                   \
    CC="fcc"                                    \
    F77="frt"                                   \
    CFLAGS='-Nclang -Ofast -ffj-no-fast-matmul' \
    FFLAGS='-Kfast'                             \
    --enable-sve                                \
    --enable-armv8-cntvct-el0                   \
    --enable-float                              \
    --enable-fma                                \
    --enable-fortran                            \
    --enable-openmp                             \
    --enable-shared                             \
    --prefix="$INSTALL_PATH"                    \
    --libdir="$INSTALL_PATH/lib64"              \
    ac_cv_prog_f77_v='-###'                     \
    OPENMP_CFLAGS='-Kopenmp'
$ make -j30

• Cross compilation using Fujitsu compiler (AArch64 target).

$ ./configure                                   \
    CC="fccpx"                                  \
    F77="frtpx"                                 \
    CFLAGS='-Nclang -Ofast -ffj-no-fast-matmul' \
    FFLAGS='-Kfast'                             \
    --host=aarch64-unknown-linux-gnu            \
    --build=x86_64-cross-linux-gnu              \
    --enable-sve                                \
    --enable-armv8-cntvct-el0                   \
    --enable-float                              \
    --enable-fma                                \
    --enable-fortran                            \
    --enable-openmp                             \
    --enable-shared                             \
    --prefix="$INSTALL_PATH"                    \
    --libdir="$INSTALL_PATH/lib64"              \
    ac_cv_prog_f77_v='-###'                     \
    OPENMP_CFLAGS='-Kopenmp'
$ make -j30

Double precision

• Native compilation using Fujitsu compiler (AArch64 target).

$ ./configure                                   \
    CC="fcc"                                    \
    F77="frt"                                   \
    CFLAGS='-Nclang -Ofast -ffj-no-fast-matmul' \
    FFLAGS='-Kfast'                             \
    --enable-sve                                \
    --enable-armv8-cntvct-el0                   \
    --enable-fma                                \
    --enable-fortran                            \
    --enable-openmp                             \
    --enable-shared                             \
    --prefix="$INSTALL_PATH"                    \
    --libdir="$INSTALL_PATH/lib64"              \
    ac_cv_prog_f77_v='-###'                     \
    OPENMP_CFLAGS='-Kopenmp'
$ make -j30

• Cross compilation using Fujitsu compiler (AArch64 target).

$ ./configure                                   \
    CC="fccpx"                                  \
    F77="frtpx"                                 \
    CFLAGS='-Nclang -Ofast -ffj-no-fast-matmul' \
    FFLAGS='-Kfast'                             \
    --host=aarch64-unknown-linux-gnu            \
    --build=x86_64-cross-linux-gnu              \
    --enable-sve                                \
    --enable-armv8-cntvct-el0                   \
    --enable-fma                                \
    --enable-fortran                            \
    --enable-openmp                             \
    --enable-shared                             \
    --prefix="$INSTALL_PATH"                    \
    --libdir="$INSTALL_PATH/lib64"              \
    ac_cv_prog_f77_v='-###'                     \
    OPENMP_CFLAGS='-Kopenmp'
$ make -j30

Run tests

$ make check

Install FFTW3

$ make install

Usage

How to compile

• Compile with the -L$(INSTALL_PATH)/lib64 option and one of the options listed in the following table after your sources or objects.

FFTW3 libraries	Options
Single precision and sequential version	-lfftw3f -lm
Single precision and thread-parallel version	-lfftw3f_omp -lfftw3f -lm
Double precision and sequential version	-lfftw3 -lm
Double precision and thread-parallel version	-lfftw3_omp -lfftw3 -lm

• If you specified --enable-linkfortran at configure, compile with one of the following options.

FFTW3 libraries	Options
Single precision and sequential version	-lfftw3f_fortran -lm
Single precision and thread-parallel version	-lfftw3f_fortran_omp -lfftw3f_fortran -lm
Double precision and sequential version	-lfftw3_fortran -lm
Double precision and thread-parallel version	-lfftw3_fortran_omp -lfftw3_fortran -lm

Example

• Case with the single precision and sequential library.

$ fcc a.c -L$(INSTALL_PATH)/lib64 -lfftw3f -lm

• If --enable-linkfortran is specified at configure, case with the single precision and sequential library.

$ frt a.f -L$(INSTALL_PATH)/lib64 -lfftw3f_fortran -lm

License

• See LICENSE file.