Correctness and performance is everything in programming. Verifying it for software is relatively easy because you can "just" run the program and see if it crashes and/or is very slow. Verifying correctness for hardware is also relatively easy because you can run the design in a simulator, but verifying performance (gate count, f_max, energy usage, size in um^2, etc.) is tricky.
So my question is how you do it when you don't have access to the target hardware (e.g ASIC or high-end FPGA)? What free tools are there that can give you (approximate?) performance metrics for HDL designs?