On Wed, 17 Jan 2007 [EMAIL PROTECTED] wrote: > (note that ARM emulation is supported, but running on ARM hardware is > noted as being in Testing) > > QEMUs ARM support if for the ARM9 chip, a 32bit only arm variant. QEMU > runs on Windows/Linux and Macos X.
If I'm reading this documentation right, it looks like QEMU goes about things in a bit of an odd way. Rather than writing their own runtime assembler and having it produce optimised code, they're just pasting C functions back-to-back. So there'll still be the same overheads with constantly loading and storing guest CPU registers to memory, etc. Granted, it's a simpler way of doing things if you can get a reliable way of pasting functions together, but it's a bit of a hack. Which perhaps explains why they're having troubles getting it running on ARM hardware :) With the simplicity of the ARM instruction set (and the fact I'm aiming for ARM-on-ARM), I was hoping to go for the runtime assembler approach (Which is helped by me already having my own simple runtime assembler). This would provide a best-case scenario of 1:1 instruction mapping. > But has now also run into issues. If anyone wants to help carrying this > on further I'll open access to the svn repository that are changes are > on. If we ever get a working RPC emulator it's our intention to submit > the changes to the main QEMU repository. I know more about the ARM instruction set than hardware emulation, so I doubt I'd be any help with that. > There's not much I can comment about writting JITs other than to say my > vague experience with QEMU is that it is bloody complicated, considerably > beyond the complexity of the interpreter in Arcem. Hopefully my brother > will answer an email for once and reply to some of your questions ;) Yes, JIT can be very complex (especially if you abuse your C compilers output like QEMU seems to do). But that's why I was aiming for the KISS approach - a simple plugin for an existing, simple emulator (ArcEm) that will initially only translate simple instruction sequences. It probably won't get anywhere near the speed of QEMU due to JITing such a small subset, but hopefully it will get it fast enough for full speed A400/RiscPC emulation on ARM hardware. Of course, if anyone can convince me that I'd be better off helping develop QEMU, then I'm still open to offers :) Cheers, - Jeffrey ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ arcem-devel mailing list arcem-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/arcem-devel
