When I worked for IBM 9 years ago, there was a hardware simulator, code name "EVE", took net-list only. I had to clone i960/VHDL to get net-list to use EVE. The entire testbench was Synthesizable.
There is a book talking about "Synthesizable Testbench": Page 20, session 2.2.5, "Principles of Verifiable RTL Design", Year 2000 by Lionel Benning and Harry Foster.
Wen |