Ryan Houdek
5472d1cc04
This does a gather load three ways, SVE256, SVE128, and ASIMD. This operation is a bit special since it it can't quite handle all gather loadstores in the 256-bit case and requires the frontend to decompose the operation in the case that the striding hits a mode that SVE doesn't support! The 128-bit case is a lot simpler since both support all the cases where stride doesn't match. I find this to be a nice compromise while there aren't any SVE256 products on the market. In the 128-bit case there is an SVE path which is utilized if the passed in stride supports what SVE understands, otherwise it falls back to an ASIMD implementation which manually emulates everything that is necessary. This instruction is very explicitly doing basically exactly what AVX gather instructions want, because it's complex enough that we don't want to try and make this a generic solution.
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 5.0+ 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 20.04, 21.04, 21.10, 22.04
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 Ubuntu 20.04, 20.10, and 21.04. Also 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
