xqemu VS QEMU

These projects are called compatibility layers, or "translation layers" sometimes. I think XQEmu (OG XBox on PC) works the same.

Yes:

https://xemu.app/

https://xqemu.com/

Are both original Xbox emulators built off of QEMU. I've only used Xemu, but performance was pretty good for the games I tried on it (it doesn't have a way to upscale rendering yet though).

It's indeed a bit like a kexec.

On system initialization, kernel routines are copied into RAM by the bootloader[1]. Executables run in ring 0, and have a jump table to call kernel routines in their own address space (IIRC) [2].

As such, loading any executable counts as a soft reboot.

Also, there is a functioning open source emulator, Xqemu [3] (and its sibling/fork focused on speed and compatibility more than accuracy, xemu [4])

I recommend reading "17 mistakes Microsoft made in the Xbox security system", which is very informative [5].

[1]: https://xboxdevwiki.net/Boot_Process

[2]: https://xboxdevwiki.net/Kernel

[3]: https://xqemu.com/

[4]: https://xemu.app/

[5]: https://xboxdevwiki.net/17_Mistakes_Microsoft_Made_in_the_Xb...

There is one emulator currently that does do that, the "XQEMU" emulator for the original Xbox https://xqemu.com/

It's in its infant stages at the moment according to the "Emulation General" wiki and focuses heavily on "accuracy" over performance

Other emulators such as CXBX-Reloaded have made larger strides, currently emulating roughly 10% of the software library

It's also worth stating, while the Xbox seems like an "easy" target, being based on an ia-32 (Pentium III) PC with an Nvidia GeForce chip (somewhere between a Geforce 2 and 3 at the time) it is an absolutely monstrous beast with minimal documentation about its hardware and numerous "gotchas"

It also has a very small library of 'exclusive' content which detracts from gaining many developers

A better solution is just to write a plain ass shell script that tests if various C snippets compile.

https://github.com/oilshell/oil/blob/master/configure

https://github.com/oilshell/oil/blob/master/build/detect-pwe...

Not an unholy mix of m4, shell, and C, all in the same file.

---

These are the same style as a the configure scripts that Fabrice Bellard wrote for tcc and QEMU.

They are plain ass shell scripts, because he actually understands the code he writes.

https://github.com/qemu/qemu/blob/master/configure

https://github.com/TinyCC/tinycc/blob/mob/configure

OCaml’s configure script is also “normal”.

You don’t have to copy and paste thousands of lines of GNU stuff that you don’t understand.

(copy of lobste.rs comment)

Related:

A fast Pascal (Delphi) WebAssembly interpreter:

https://github.com/marat1961/wasm

WASM-4:

https://github.com/aduros/wasm4

Curated list of awesome things regarding WebAssembly (wasm) ecosystem:

https://github.com/mbasso/awesome-wasm

Also, it would be nice if there was a WASM (soft) CPU for QEMU, which (if it existed!) would go here:

https://github.com/qemu/qemu/tree/master/target

> architectural registers are always updated

In tiny code, the guest registers (global TCG variables) are stored in the host's registers until you either call an helper which can access the CPU state or you return (`git grep la_global_sync`). This is the reason why QEMU is not so terribly slow.

But after a check, this also happens when you access the guest memory address space! https://github.com/qemu/qemu/blob/master/include/tcg/tcg-opc... (TCG_OPF_SIDE_EFFECTS is what matters)

But still, in the end, it's the same problem. What QEMU does, can be done in LLVM too. You could probably be more efficient in LLVM by using the exception handling mechanism (invoke and friends) to only serialize back to memory when there's an actual exception, at the cost of higher register pressure. More or less what we do here: https://rev.ng/downloads/bar-2019-paper.pdf

Um, in case you don't know, UTM (based on QEMU) is out for quite a while.

Some of these tools include Oracle VM VirtualBox (that I've used since before the acquisition of Sun Microsystems by Oracle), VMWare Workstation Player, and QEMU, but last year, I found out about Multipass.

For C/C++ projects that use meson as the build system, there is an excellent way to manage dependencies:

https://mesonbuild.com/Wrapdb-projects.html

https://mesonbuild.com/Wrap-dependency-system-manual.html

meson will download and build the libraries automatically and give you a variable which you pass as a regular dependency into the built target:

https://github.com/qemu/qemu/tree/005ad32358f12fe9313a4a0191...

https://github.com/harfbuzz/harfbuzz/tree/main/subprojects

https://github.com/harfbuzz/harfbuzz/blob/37457412b3212463c5...

Or, if you're using proper operating systems, they're managed by the usual package manager, just like everything else.

For all the users of the Linux platform, QEMU is the VM that you should go for. This software comes without any price tag and works as an emulator of various machines with utmost ease and completion; the software uses dynamic translations to emulate hardware peripherals and enhances its overall performance. If you are using QEMU as a virtualizer, then it will function exactly like the host system (provided you have the right set of hardware).

In this tutorial, we set up macOS and Windows virtual machines on UTM, a macOS application that provides a GUI wrapper for QEMU, a powerful open-source emulator and virtualizer. UTM allows you to easily manage and run virtual machines without memorizing complex commands. It also has special handling for macOS, making it simpler to install compared to other virtual machine software.

I think you will need to build it yourself which you can do so by: Checkout the qemu repo and its submodules using the steps here: https://en.wikibooks.org/wiki/QEMU/Installing_QEMU in 'Building from Source' except for step 1 use the 'git clone https://github.com/qemu/qemu.git' Step 9 is where you enable the features, the build system does this by checking if you have the dev and or lib packages for the feature installed i.e. spice development packages will enable spice functionality, use the output from configure to help you with this then continue to step 10