Ryan Houdek
ffca27cbde
This is solving a different problem than what #4411 is specifically trying to solve. For our transcendental operations, we can't currently guarantee that these functions will actually operate at the 128-bit softfloat precision. While this is true with glibc, this is /not/ true for musl and likely more libraries. Instead of relying on our libc implementation to implement these, instead include the cephes math library directly which is what most people use for this. Including musl even, but not for all operations. With this we are no longer beholden to the standard libraries for providing a correct implementation.
FEX - Fast x86 emulation frontend
FEX allows you to run x86 and x86-64 binaries on an AArch64 host, similar to qemu-user and box86. It has native support for a rootfs overlay, so you don't need to chroot, as well as some thunklibs so it can forward things like GL to the host. FEX presents a Linux 5.15+ interface to the guest, and supports only AArch64 as a host. FEX is very much work in progress, so expect things to change.
Quick start guide
For Ubuntu 22.04, 24.04 and 24.10
Execute the following command in the terminal to install FEX through a PPA.
curl --silent https://raw.githubusercontent.com/FEX-Emu/FEX/main/Scripts/InstallFEX.py --output /tmp/InstallFEX.py && python3 /tmp/InstallFEX.py && rm /tmp/InstallFEX.py
This command will walk you through installing FEX through a PPA, and downloading a RootFS for use with FEX.
Ubuntu PPA is updated with our monthly releases.
For everyone else
Please see Building FEX.
Getting Started
FEX has been tested to build and run on ARMv8.0+ hardware. ARMv7 hardware will not work. Expected operating system usage is Linux. FEX has been tested with the following Linux OSes:
- Ubuntu 22.04
- Ubuntu 24.04
- Ubuntu 24.10
- Arch Linux
On AArch64 hosts the user MUST have an x86-64 RootFS Creating a RootFS.
Navigating the Source
See the Source Outline for more information.
Building FEX
Follow the guide on the official FEX-Emu Wiki here.
RootFS generation
AArch64 hosts require a rootfs for running applications. Follow the guide on the wiki page for seeing how to set up the rootfs from scratch https://wiki.fex-emu.com/index.php/Development:Setting_up_RootFS
