Does Lattice provide a Fast Fourier Transform (FFT) Compiler IP Core with VHDL as the target language in Lattice Diamond Tool?
Lattice only provides the Fast Fourier Transform (FFT) Compiler IP Core in Verilog version. In case you generate VHDL version, then only the top level wrapper will be generated in VHDL, while the behavioral model will be in Verilog language only.