Tests and examples of using formal verification to check correctness of digital hardware designs. All tests are done with SymbiYosys, a free formal verification tool based on Yosys. Some examples use the VHDL/SystemVerilog parser plugin by Verific which isn't free SW and nit included in the free Yosys version. See on the Symbiotic EDA website for more information.
A simple ALU design in VHDL, together with a formal testbench written in SystemVerilog. The testbench contains various simple properties for assert & cover directives which are proved with the SymbiYosys tool.