GHDL
VHDL 2008/93/87 simulator
...It can handle very large designs, such as leon3/grlib. GHDL runs on GNU/Linux, Windows and macOS; on x86, x86_64, armv6/armv7/aarch32, aarch64 and ppc64. You can freely download nightly assets, use OCI images (aka Docker/Podman containers), or try building it on your own machine.