I have recently re-installed Linux, this time with Arch instead of Debian, onto my old Mac Mini G4, as well as setting up SSH for X tunneling and such. This means I can now easily work on anything on my PowerPC machine from anywhere with an internet connection (it also means I can keep my dual-monitor setup, since I can just tunnel in from my regular machine).
Thanks to this wonderful advancement, I can now start working on a dynarec core for PowerPC. This will likely be a long arduous task, but it’s well worth it, in that 32bit PowerPC machines (and maybe 64bit ones as well?) will be able to run MAME with far better performance on newer games.
Before I go, here are some quick benchmarks:
| Game | Raw interpreter | UML interpreter |
| Gunbird 2 | 58% | 24% |
| Strikers 1945 II | 56% | 22% |
| Avengers in Galactic Storm | 63% | 112% |
| Cyvern | 38% | 73% |
By the end of this, I should have 100% at the least for these games!
Congratulations on the progress of this project.
I’m looking forward to it, as I’m interested in a PowerPC dynarec for the MorphOS port of MAME (MorphOS runs amongst other on Mac mini G4).
Since 0.126 or so, i haven’t released any new version because of the introduction of this slow UML interpreter, which gives terrible results on SH2 emulation.
But i have a question that you may answer…
In 0.120 times, gunbird2 would actually run >100% with the old SH2 interpreter. In more recent versions (0.130 to 0.140), i tweaked MAME a bit to use the old SH2 interpreter instead of the UML one, but i still get substancially slower results (50% or so). Do you know where this huge performance difference come from?
Comment by Fab — 2011/01/16 @ 06:41
It likely comes from the changes that Aaron Giles has been making to the MAME internal core which are, to say the least, highly inefficient. Particularly from 136u1 on, they’ve been getting worse and worse due to his C++ification of MAME (C++ isn’t the problem, it’s that a bunch of very slow features of it are being used for not very good reasons).
Comment by trap15 — 2011/01/17 @ 01:08
This might sound like a stupid question, but since the notion of a fully-fledged Dynarec for the PowerPC architecture is here, do you think it will be possible to port said program to the Nintendo Wii in the future?
http://en.wikipedia.org/wiki/Broadway_(microprocessor)
I realise it’s a bit of a stretch, but the Wii Homebrew community really needs something better than SDL MAME Wii which is so dodgy with game support it isn’t funny (no offense intended to Toad King who made it though).
Comment by BPzeBanshee — 2011/01/19 @ 01:41
Yes, that was one of the main targets for this, actually.
It’s just that my Mac Mini G4 is a tad^Wlot faster than my Wii, so I could port it easier.
Comment by trap15 — 2011/01/19 @ 13:45
hi, sounds really good that you want to implement the ppc dynarec backend. Since this message is from January, I want to ask about the progress so far. Thank you!
Comment by Thore — 2011/09/18 @ 01:48
It’s basically been canceled. Sorry.
Comment by trap15 — 2011/11/01 @ 01:59