QEMU
Introduction
QEMU is an open source processor emulator, of which two independent RISC OS-related projects exist.
User-mode emulation
Changes were made by the GCCSDK developers in order to let it run unmodified AIF and ELF based RISC OS binaries in its user mode emulation (Linux only). Combined with Linux's binfmt_misc kernel module such RISC OS binaries can be run as normal Linux processes.
These changes have been made in order to easily test GCCSDK produced binaries using testtools like GCC own testsuite based on DejaGnu. For this a minimal subset of the RISC OS SWI API is implemented. This SWI API can be easily further enhanced by explicit C++ code or by loading unmodified RISC OS modules (like GCCSDK's own SharedUnixLibrary module is loaded).
Source
The RISC OS specific changes to QEMU together with build and install instructions can be found in our QEMU source repository.
System-mode emulation
Daniel Clarke has done much of the groundwork for emulating the Risc PC's hardware (including 26 bit ARM instructions) in QEMU's system mode, which provides a full system emulator including JIT with many hardware emulations supplied by QEMU (network, USB, CD, floppy, parallel, serial, etc). It should run on any platform and OS that will support QEMU. Currently it needs work fixing bugs in order to get it to boot RISC OS or ARM Linux.
