> > Of course, everyone should be running 64-bit MAME anyway, we can't guarantee MAME > > will run much longer in 32-bit environments. > > > > Can you give some example where/how 64-bit code differs from 32-bit code. Is it > not, > > or can it not be, just a compiler option settings? > > 64-bit code is about 20% faster overall for free in emulation environments, and it > often provides similar benefits to PC games. There are 16 registers instead of 3 to 5 > and more instructions work on all of them (instead of MUL always putting the results > in specific registers) so the compiler can generate much more optimal code. > > Also, we're looking to start emulating things (like certain newer handhelds) where > the ROMs are 2/3/4 GB, which has trouble fitting at all in a 32-bit system.
More importantly, in my opinion, is the fact that even the video game industry is moving towards 64-bit executables. As much as people think otherwise, the game industry tends to play it exceedingly safe, to the extent that we're only now seeing games starting to require a 64-bit machine. When such a traditionally-cautious market starts pushing for 64-bit builds, it becomes that much harder to justify shipping 32-bit builds as the default.
It's unfortunate that there are some people out there who can't get 64-bit machines, either due to money or other reasons, but I don't see why the project should be held back performance-wise because of that.