moved all globals into a single global struct -> 3% speedup with clang :)
The state pointer is no longer global, but passed down to every function.

...and surprisingly, it's not any slower. if anything, it's 1% faster.
updated copyright
cleaned up node names
malloc'ed all state instead of having a gigantic struct

state_t is now 208 bytes on x86_64 instead of 26 MB. Startup is a little slower though because of ~7000 malloc calls.
cleanups
actually de-dup transistors!
cleanups
cleanup
cleanup
cleanup
split code into generic netlist simulation and 6502-specific code
cleanups
moved nodes names into netlist_6502.h