I'm an FPGA noob but I really like ghdl. It also has a feature to check code is synthesizable and translate it down to a vhdl 93 netlist, so you can use modern

I'm an FPGA noob but I really like ghdl. It also has a feature to check code is synthesizable and translate it down to a vhdl 93 netlist, so you can use modern features that proprietary synthesizers may not support in your vhdl codebase