sse2neon VS termux-packages

The sse2neon project is a quick way to get C/C++ applications compiling and running on Graviton. The sse2neon header file provides NEON implementations for x64 intrinsics so no source code changes are needed. Each function call (intrinsic) is simply replaced with NEON instructions and will just work on Graviton.

To continue our collaboration I contributed some small changes to KasmVNC on GitHub to use sse2neon for a performance critical part of the application which uses SSE intrinsics and needed to be changed to NEON intrinsics.

I think the talk is very clearly laid out as an incremental journey, and each stepping stone involves contextual decision-making. I don't think Andreas is saying "you must end up with the SSE2 implementation at the end". Using machine-specific intrinsics is another dependency decision very similar to deciding to use a given library. I would have loved the talk and probably still thought of it and posted it, even if it ended before the intrinsics (but I think he does an excellent job at that part too).

And porting SSE2 to Neon is actually pretty easy -- if you use https://github.com/DLTcollab/sse2neon, IME it's very easy to do incrementally (or avoid or postpone indefinitely, depending on your needs).

I have a private cross-platform port, I’m waiting on the resolution of his latest GitHub issue to submit my changes. sse2neon (https://github.com/DLTcollab/sse2neon) was a big help - I also wrote a very primitive sse2scalar for raspbian builds where neon is unavailable. Honestly SIMD doesn’t help much, as you’re usually memory bound under SWGL. The biggest perf win is any amount of asynchronous execution - running off the main thread is good enough and could be applied to your library externally through a command buffer without any changes to your code.

You should go to /include/simd and download sse2neon.h into the folder. Replace appearing in any source files in that directory with "sse2neon.h". You will still encounter errors; remove the lines causing problems, typically containing the phrase ZERO_MODE. ARM processors does not require it.

usbredirect, USB drives/disks, Termux, termux-usb, QEMU, and Alpine Linux in action in April 2024 on an Android 11 phone that is not rooted --> Update-6, Update-7, Update-8, Update-9, Update-10 at https://github.com/termux/termux-packages/issues/19635

"USB Network Redirection protocol description version 0.7 (19 May 2014)": https://gitlab.freedesktop.org/spice/usbredir/-/blob/main/do... (gitlab.freedesktop.org/spice/usbredir/-/blob/main/docs/usb-redirection-protocol.md)

"How to use Spice "Open remote computing"" Hans de Goede "@ T-DOSE 2011, Eindhoven": https://www.youtube.com/watch?v=e1fC3GOTHOY (www.youtube.com/watch?v=e1fC3GOTHOY)

Phone (not rooted) running Android 11 and Termux doing superuser/root operations on a USB flash drive connected to the phone, for example "cryptsetup luksFormat /dev/sda1" and "mkfs.ext4 /dev/mapper/v1" --> Update-6 through Update-8 and "Connecting a USB device to QEMU using termux, termux-usb, usbredirect" at https://github.com/termux/termux-packages/issues/19635 (see also Update-9, Update-10, Update-11).

Done on a phone that is not rooted running Termux, termux-usb, usbredirect, and QEMU --> "cryptsetup luksFormat /dev/sda1" and "cryptsetup luksOpen /dev/sda1 v1" and "mkfs.ext4 /dev/mapper/v1" and "mount /dev/mapper/v1 /root/1" where "/dev/sda1" is a partition on a USB flash drive ("dev/sda") plugged in the phone: https://github.com/termux/termux-packages/issues/19635 (github.com/termux/termux-packages/issues/19635'cryptsetup)

Yes. Even without enabling root, you can install Termux[1] and have a full Linux cli environment with ssh.

> don't understand not more people want to access their DCIM folder via sshfs

I agree. I sync my camera folder with Syncthing[1], so as soon as I take a photo it is available on my laptop.

1: https://termux.dev/

As usual don't forget that Android/Linux isn't GNU/Linux,

https://github.com/termux/termux-packages/wiki/Termux-and-An...

https://developer.android.com/ndk/guides/stable_apis

https://android.googlesource.com/platform/bionic/+/master/an...

With this, I was able to cross compile lone for x86_64 from within the Termux environment of my aarch64 smartphone. All I had to do was obtain the Linux user space API headers for x86_64.

I made a Termux package request for multiplatform Linux UAPI headers specifically so I could cross compile lone but unfortunately it was rejected.

https://github.com/termux/termux-packages/issues/16069

I wonder how far you could get with the git client in termux. I got vim running at one point.

[1] https://termux.dev/

[2] https://packages.termux.dev/apt/termux-main/pool/main/g/git/

Crystal can be installed with just pkg install crystal. If you have Docker, you could also clone the build environment and try building Crystal locally with scripts/run-docker.sh scripts/build-package.sh -I -a aarch64 crystal.