Never heard of Spiral but it looks really interesting, particularly compared to MKL and FFTW. It’s been possible for a long time for C and C++ compilers to use

Never heard of Spiral but it looks really interesting, particularly compared to MKL and FFTW. It’s been possible for a long time for C and C++ compilers to use “profile guided optimisation”, but it’s not widely used in practice because it’s pretty awkward to leverage.